FAQ Chia-Network/chia-blockchain Wiki GitHub

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Table of ContentsWhat are harvesters, farmers, full nodes, and timelords?

You can read about each of them and the architecture in the network architecture document. The consensus document is the most current documentation, however. You can also check out our Timelord documentation.

A proof of space is a proof that a farmer has allocated a portion of their storage in a way that is very difficult to create in real-time but efficient to pre-compute and store on a hard drive. The Chia Proof of Space Construction document goes deeply into the math and implementation considerations to mitigate Hellman's Time - Memory tradeoff problem. A plot is a large set of proofs of space. A harvester can harvest multiple plots on the same machine. A farmer can then control multiple harvesters across many machines to manage the whole "farm."

Farming uses substantially less electricity than Proof of Work for the same unit of security. You can learn more at chiapower.org.

A VDF, also known as a proof of time, is a sequential operation that takes a prescribed amount of time to compute (and which cannot be accelerated by parallelism) and which produces an accompanying proof whose result may be quickly verified. This must be done in a group, for which Chia uses ideal class groups. You can learn about them in our class group document. Timelords usually run three VDFs at a time for the three internal blockchains of the Chia blockchain. They run as vdf_client processes.

XCH is the currency symbol for Chia. TXCH is the currency symbol currently being used for testnet chias. TXCH has no value and is only used for testing purposes. Chias and testnet chias can be divided up to 12 decimal places (trillionths). The smallest unit of chia, a trillionth of a chia, is called a mojo, as a tribute to Mojo Nation, a decentralized file storage platform created in the early 2000s by Zooko Wilcox, Bram Cohen, and others.

"k" is the space parameter that controls the size of plots. It is an integer for the following equation: plot_size_bytes = C1 * 2^k(k + C2) where C1 is constant 1 and C2 is constant 2. In practice this means that final size is roughly ((2 * k) + 1) * (2 ** (k - 1)) * 0.762 though that constant is estimated. You can examine the Space Required section of the Chia Proof of Space Construction document for the calculation of how much space is required for a given k.

You can see some example plot sizes, times to plot, and working space needed based on various k's in these k size tables. Current working space needed for the default plotting options of a k=32 is 239 GiB and the final file is approximately 101.4 GiB. There is small natural variation in temp space needed and the final file size of each plot. Note that 239 GiB is 256.6 GB.

The minimum plot size is k=32. There is only one reason why you might want to plot larger than k=32: to maximize the total utilization of a given drive or space. A couple of k=33 plots with a majority of k=32 plots can reduce the amount of leftover unused space on a drive.

The reason k=32 was chosen as the minimum plot size was to prevent a short-range replotting attack, which is detailed in our consensus doc. The gist of the attack is that if someone can create a plot in less than ~30 seconds, they could create a new plot that passes the filter for each signage point, and then delete the new plot immediately afterward. This would effectively emulate storing 512 plots, thus turning Chia into PoW.

This attack won't be economically feasible for some time, if ever. Two potential mitigation techniques are to lower the plot filter (thus reducing the benefit of the attack), or to increase the minimum plot size (thus making the attack more difficult to perform).

k=32 is expected to be the minimum plot size until at least 2026. If and when that size is increased, you will be given ample notice to replot before the change is made effective.

We think you will want to use used Data Center grade NVMe SSD drives to create your plots. Regular consumer NVMe SSD generally has too low of a TBW rating. One of our community members keeps this handy SSD Endurance document up to date so you can compare various SSDs. You should never use your root/OS SSD to plot as it can lead to drive failure and loss of booting. You can plot directly to hard drives and get good results, especially if you plot in parallel to different drives. You can use non-root SSD over Thunderbolt 3 and migrate your plots off to whatever storage you want to keep them on long term. You could even load them on a Raspberry Pi 4 with outdated USB 2.0 drives attached and they will harvest and farm just fine. PC World offers this great background on current storage technologies but this graph gives you a quick view of why we recommend NVMe SSD:

Yes, using either the GUI or CLI. Over the short run you have a bit more control of plotting using the CLI. There are tips for Windows users and Mac users can find their CLI commands in the Quick Start Guide. You may have better results if you stagger the start time of parallel plotting processes depending on your hardware setup.

Yes. The moving plots topic here on the wiki gives you the details. You may also want to consider running a remote harvester. You can also use the same private key set to plot on more than one machine at a time but be aware of the uPnP issues.

-2 is in use during phase 3 and 4. It is the file being built into the resulting .plot file. As it is done compressing tables during phase 3, it will move them into the .plot.2.tmp file (-2), and phase 4 will scan through the entire .plot.2.tmp (-2) file, and write table headers for easy access by the harvester. When phase 4 is done, if -2 = -d, it will simply rename the .plot.2.tmp to .plot. If -2 != -d, it will copy the file into place, then rename, and finally remove the -2 file. The amount of writing is about 110% of the resulting .plot file size. It is a setup dependent option - is your setup faster at moving the compressed tables into the .plot.2.tmp file, and then scan through the entire file, and write table headers during phase 4 - and then copy to -d (-2 = -t) - or is it faster to send the compressed tables directly into the -d (-2 = -d) directory, and then in phase 4, scan through the entire file, and write table headers inside -d (-2 = -d) thereby skipping the final copy into place. The -2 directory can be set in the Advanced Options for Step 3 in the GUI.

If you see something like Caught plotting error: Not enough memory for sort in memory. Need to sort X.XXGiB then you need to either select more memory buffer or more buckets. More buckets require less memory but will create more temp files and more sporadic disk writing. You will almost always want to use 128 buckets and you should try increasing the RAM max usage/-b to 4608MiB.

This is a RAM problem with your machine. It can be how your swap file is configured. It is often your overclock, or XMP settings and even can be a faulty RAM stick. Chia plotting is better than memtest at surfacing broken or mis-configured RAM.

Unfortunately, resuming a plot is not supported. We suggest that you disable power saving mode - especially for external drives - and try to limit other possible causes of interruptions. Plotting a k=32 could take multiple hours, depending on your hardware, so these interruptions can be painful. They are also a part of why we don't recommend plotting plots larger than k=32 as each increment in k generally doubles the time to complete a single plot.

No. Plotting can be done entirely offline and needs nothing from the blockchain to complete. The only time you have to be online and synced is when you're farming so that you receive new challenges for the next blocks and transactions to include in a transaction block if you're lucky enough to win one of them and get the transaction fees. Note that one farmer winning is independent of other farmers winning at the same time. All farmers can "win" at nearly the same time. That is why sometimes there are 10 blocks in one minute, and sometimes there is only 1 block per minute, etc.

No. As long as you plot at least k=32, those plots will be eligible to win on mainnet. In a decade or more, k=32 may become too small, but that's speculative. Usually the only reason to plot larger than k=32 is to optimize using all of the space on a given drive. For example, it may make sense to have two k=33's and the rest k=32 so that you only leave 10 GB free on a given drive.

Yes.

Run chia plots check -n 30 to try 30 sample challenges for each plot. Each of your plots should return a number around 30, which means it found around 100% of the attempted proofs of space. If you're still worried try -n 100 as more random attempts will give you a more valid assessment that the plots is fine. It really is ok if your plot is within 80%-120%. If some of your plots are missing for some reason you may need to add the directory they are in to your config.yaml file. That can be done in the GUI with the MANAGE PLOT DIRECTORIES button or on the command line with chia plots add -d [directory].

UPnP is an optional setting that allows users to open a port in their router and therefore allow other nodes to connect to them. This is not required, since your node can still make outgoing connections without UPnP.

For some routers, UPnP is enabled automatically, but for others, you might have to go into your router settings and enable UPnP manually. Sometimes restarting the router is also necessary.

Another option is port forwarding, where you tell your router/NAT to forward requests on port 8444 or 58444 for testnet to your machine.

First, running more than one node with the same private keys on your home network is wasting bandwidth by syncing two copies of the blockchain over your download link. You can get the same results by running one node and using multiple harvesters on multiple computers. Second, if you have uPnP enabled on both nodes and your home router supports uPnP (and most do) it will cause both of your nodes to not sync the blockchain. You need to disable uPnP on all or all but one node behind a uPnP enabled router. The CLI command chia configure --enable-upnp false will turn uPnP off on a node. It requires a restart of the node to take effect. If you disable UPnP on all but one of your nodes then your local router will forward inbound 8444 traffic to the one node and the rest will now be able to connect to the network but just will not accept inbound connections from the network.

Step 1. Make sure you are running the most recent version of the Chia software. Check out the INSTALL page.

Step 2. If your node has no connections, it could be one of many reasons. The most likely reason is that there are no users with space to have new connections, so you cannot connect to them. To solve this, you should try opening port 8444 on your router so other peers can connect to you. Follow the steps here: Resolving Sync Issues Port 8444

Port 8444 is the port through which other Chia computers can communicate with your PC. When you set up port forwarding on port 8444, the Chia software on your computer can quickly talk to other PCs, link up, and start downloading and syncing with the Chia blockchain.

The network is undergoing rapid growth and expansion. Many of the newly arrived Chia peers (computers) do not open up port 8444. It makes it very hard for the network. So please port forward on port 8444!

Use this link to check if your router's port 8444 is closed: https://portchecker.co/

Step 3: You might need to disable UPnP in the config file (~/.chia/mainnet/config/config.yaml) or by using the cli command chia configure -upnp false. You might have multiple nodes running on the same machine, or in the same wifi network. Make sure to close all Chia applications on your computer. Also check your firewall or antivirus software, which might be blocking connections.

Step 4: Try deleting your peer DB which is located at ~/.chia/mainnet/db/peer_table_node.sqlite. Close then restart Chia.

Step 5: Edit ~/.chia/mainnet/config/config.yaml, search for weight_proof_timeout and increase it from 180 to 400. If that value is not there, you can add it under the full_node section.

It can take a few minutes to start receiving peers and several hours to completely sync.

This is usually a system clock issue, which is causing the display of "Not synced", even though you are. Your clock must be set to the exact time, and cannot be more than 5 minutes off. Check your phone and your computer and ensure the time is the same.

Beginning in 1.3, Chia uses version 2 of its blockchain database. The new database is still written in SQLite, but it has undergone a series of optimizations, such as storing hashes in binary, rather than human-readable hex format. It also is more compressed than version 1. These two factors combined have resulted in an approximately 45% reduction in the size of the database, as well as a slight improvement in its performance.

If you install a brand new full node in Chia 1.3 or later, version 2 of the database will be created when you run chia init. If you want to stick with version 1, simply run chia init --v1-db instead.

If you were already were running a full node prior to upgrading to Chia 1.3, the upgrade will not happen automatically. The command to perform the upgrade is chia db upgrade. This is documented in detail in our CLI reference.

You do not need to stop Chia in order to perform the upgrade. This is because the program performing the upgrade only needs to read from your original database file, while your upgraded file will be written alongside it in the same folder. Be sure you have enough free space on the disk that contains your database file to write the new file.

The current size requirement (2nd quarter 2022) is around 55 GB. Note that the database is always growing, so the size requirement for the v2 database will have gone up by the time you are reading this plan accordingly.

The upgrade could take several hours, so feel free to perform it at your leisure. After the upgrade has completed, run chia start farmer -r to restart your farmer and switch to the new database.

Note that the new database will have the same peak as version 1 at the time you initiated the upgrade. Your node will still need to run a short sync to fetch the remaining blocks that had gotten added while the upgrade was being performed.

Because the upgrade from version 1 to 2 of the database is time-consuming, most users will likely only perform it on one of their systems and copy the new database file to their other systems afterward. If you choose this option, be sure to either copy the file before running chia start farmer -r, or stop Chia altogether if it is already using the new database. Once the database is swapped from v1 to v2, you also need to update you config.yaml to reflect the new v2 database change. Under the full_node: section set database_path: db/blockchain_v1_CHALLENGE.sqlite to database_path: db/blockchain_v2_CHALLENGE.sqlite

WARNING: If you copy your database file to another computer while Chia is currently using it, you'll risk corrupting it, which will necessitate a full sync from genesis.

If you're interested in learning more technical details of the new database, see the first Github Pull Request that introduced the changes:https://github.com/Chia-Network/chia-blockchain/pull/9442

And there were two follow-up Pull Requests with additional improvements, along with some benchmarks.https://github.com/Chia-Network/chia-blockchain/pull/9454https://github.com/Chia-Network/chia-blockchain/pull/9455

Finally, here is the Pull Request that added the upgrade functionality:https://github.com/Chia-Network/chia-blockchain/pull/9613

When you load Chia's client GUI for the first time, you'll be asked to choose whether to run in Wallet Mode or Farming Mode. Here are the main features of each mode:

Wallet Mode:

Farming Mode:

To switch between Wallet Mode and Farming Mode, click the gear icon on the upper-right side of your client. The settings menu will appear. Click the desired mode.

Note that in both modes, the light wallet protocol is always used. This protocol will sync your wallet by only downloading information from a subset of the blocks. The more transactions your wallet has had, the longer this process will require.

The following are situations when your wallet will NOT connect to external peers:

For example, let's say you're running Chia for the first time and you have not modified connect_to_unknown_peers. Here is one potential workflow:

Depending on how you are using your Chia client, we recommend the following:

There are two types of peer nodes -- trusted/known and untrusted/unknown. By default, your local node is your only trusted node. It is possible to add other nodes to the trusted list, for example if you personally run more than one full node. One reason to add a trusted node is to speed up the sync time of your light wallet.

The light wallet protocol has two techniques to sync:

Typically, it is much faster to sync a wallet by connecting to a trusted node. Therefore, if you have access to a synced node that you trust, you may want to add that node to your trusted peers list. We recommend that you only add your own full nodes to this list.

Inside the wallet: section in config.yaml, you should see trusted_peers:. Add a new line with the value of Node ID, like this example (do not use this Node ID, use the one from your trusted node):

This response will give a non-technical overview of Chia's light wallet syncing process. For technical info, see our docs site, as well as the FlyClient White Paper, which details the process from which Chia's light client is based.

First, a bit about addresses in Chia. A single Chia wallet can use up to four billion (2^32) addresses. Hopefully, you won't need more than that! Using multiple addresses can help provide anonymity. Rather than having to sign up for a new account each time you want to receive money, you can simply click "NEW ADDRESS" and presto -- a new address appears. Additionally, each time you receive change from sending money, a new address is automatically generated. Your wallet keeps track of each of the addresses that have been used. As long as your wallet is synced, it always knows how much money you have.

One important thing to remember is that your wallet addresses will always be generated in the same order. When you generate a "new" address, you're actually calculating the next address in the sequence. Your wallet doesn't know what the next address will be until it's generated, but the sequence will always be the same. For example, if you generate 50 new addresses (and write them down), and then install Chia on a new computer and import the same wallet, the first 50 addresses you generate will exactly match those from your original computer.

Next, we'll introduce a setting called initial_num_public_keys. This setting is part of config.yaml, located in ~/.chia/mainnet/config on Linux and MacOS, and C:Users.chiamainnetconfig on Windows. The default value of this setting is 100. The majority of users should not change it.

You can think of initial_num_public_keys as the number of future addresses to examine. It's a window that expands with time (and never contracts). Here's how it works:

The first time you run Chia's software, your wallet will attempt to sync. It does this by checking the first address in the sequence. If that address has ever received money, your wallet will account for that transaction history and examine the next address, and so on. It would take a very long time to examine all four billion addresses, so your wallet will stop looking at some point. This is where initial_num_public_keys comes in.

By default, your wallet will stop after it has examined 100 straight addresses that have never received money. If it examines 50 empty addresses and then finds a transaction on the 51st address, the number left to examine is reset back to 100. Because the addresses always appear in the same sequence, it will be rare to have even a single address without any transaction history. But there is one exception: if you click "NEW ADDRESS" twice, then one address will remain unused. If you click "NEW ADDRESS" 101 times without receiving money at any of those addresses, then you'll have 100 consecutive unused addresses in the sequence. Let's say you receive money at the 101st address. When your wallet attempts to sync, it will stop looking after the 100th blank address. Transactions from subsequent addresses will remain undiscovered, and your balance will be incorrect.

The default setting for initial_num_public_keys is quite conservative -- it should be rare for anyone to click "NEW ADDRESS" more than 100 times without actually using any of those addresses. That said, you might have a legitimate reason to do this, for example if you're running an exchange. In that case, feel free to set initial_num_public_keys to a higher number, stop your wallet, delete your wallet database, and start your wallet again to begin a fresh sync.

Why not set initial_num_public_keys to a higher number by default? Because it would take longer for your wallet to sync. Why not set it lower? If the default setting were 2, most wallets would likely still show the correct balance and the sync time would be faster. However, we set the default to 100 to prioritize showing the correct balance over syncing as fast as possible.

How does your wallet know it has the correct info for each address? It polls one or more of its peers. These peers can be either trusted or untrusted, as explained in the previous question. By default, your own node is the only one you trust. If your node is fully synced, then your wallet only needs to query your node to determine your transaction history for each address. If your node is not fully synced, then your wallet will query a number of peers about this info. If any of them lie, omit info, or disconnect in the middle of a query, your wallet will know because the responses won't all match.

If you believe your balance is incorrect, changing initial_num_public_keys is unlikely to fix the problem. If at all possible, you should sync a full node, stop Chia, delete your wallet database, and start Chia again. This time, Chia will sync based on your own node alone. If this is not an option, then resyncing from untrustred nodes might fix the problem as well.

If you see plots in the Plots section of the Farm page in the GUI - your plots are being farmed. You will see challenges and proof attempts as they come through in the Last Attempted Proof section however you usually will not have a proof worth sending to the network due to the plot filter. You can additionally see the Total Size of Plots on the Farm view and it will tell you how much unique space is being farmed and statistically how long it should take - on average - to win a block.Also, your node needs to be synced for you to farm properly. In the GUI, check the Full Node page. On the cli, do chia show -s -c.

No. You have 30 seconds to respond to challenges.

ChiaCalculator.com does a good job at running the numbers.

First, the bad news. Statistically, it would take multiple years to win a reward with a 10-TB farm. ("So you're saying there's a chance...")

Now, the good news. You can join a pool and collect regular rewards, no matter your farm's size! See our Pooling User Guide for more info.

Farmers compute a plot filter based on the signage point, their plot id, and the sub-slot challenge - which are hashed together to create the plot filter bits. If the plot filter bits start with 9 zeroes, that plot passes the filter for that signage point, and can proceed. This disqualifies around 511/512 of all proofs of space on the network, for each signage point. There are 4608 * 2 or 9216 signage points per day so the average plot should pass the filter 18 times per 24 hours on average. Once a plot passes the plot filter it then competes for the best proof of space with every other plot that also passed that plot filter for that signage point. For reasons that aren't super simple to intuit, the only thing each plot is competing on is to have the best proof of space and thus the chances of getting a reward depend on total size of plots on the farm - even with the plot filter in place.

As long as the plot passes the filter, and do not have any internal file errors, the plot will always be eligible to compete for the best proof of space. Moving the plot to another directory or server will not change its eligibility.

Please note that the speed of your lookups when passing the plot filter should be below 5 and preferably below 2 seconds. When you actually win a reward, your drive will have to do more lookups than these, so it's important that the the lookups are happening fast.

Yes you can. Please check the Pooling User Guide.

There is a possible attack where an attacker who can co-ordinate N deep from the tip of the chain can try to coerce a winning farmer to re-write a historical transaction block. This attack is much more difficult and thus less of a risk in new consensus and thus we only recommend deleting and re-plotting a plot to farmers with in excess of 1PB of farm size. Anyone smaller than that would be difficult for an attacker to locate and can more safely continue to farm plots that have already won. We plan to have the software automate the process up to and including kicking off a remote plotting process if the current hardware that a farmer or harvester are on is not up to the task of re-plotting. But to repeat, deleting winning plots is, and will always be, totally optional.

No, your plots are virtually unaffected by the passage of time, aside from hardware errors. Even in the presence of bit flips due to aging hardware, plots remain mostly effective. The only cases where you would need to re-plot are: 1. if you are using solo plots (not NFT plots) and wish to join a pool (please see note below) or 2. if hardware speeds advance to the point of a certain k value becoming obsolete (e.g., k=32 becomes too fast to plot and we ban them, forcing you to replace them with k33 plots). For case 1., you are free to have any mix of solo plots and pool plots if you do not want to re-plot. For case 2., k=32 is not expected to become outdated until sometime between 2026-2031.

It is unlikely, but it is possible. There are multiple reasons why this might be the case. The most common is that due to network delay, or drive speed delay (for example using a slow NAS), you missed the time for inclusion into the blockchain, which is 28 seconds. This time is from when the timelords create the signage points, to when the timelords infuse your block. Check to make sure that you are connected and synced to multiple peers, and that your quality lookup are fast (<2 seconds, definitely less than 5). Another reason might be that the signage point where you won did not get included into the blockchain. This can sometimes happen, since timelords may publish signage points that don't end up on chain.

The Wallets page in the GUI will display your receive address and provide an interface for you to spend your chia funds. You can also obtain a new wallet receive address any time you would like and those funds will all come to the same place as they are based on HD Keys.

There is growing wallet functionality available on the command line. Try chia wallet -h. Wallet software also provides features related to CAT's, and trade offers. You can get a receive address on the cli with chia keys show.

The coin (or UTXO) model is a Bitcoin-style transaction model which is also used in Chia. Your wallet keeps track of a set of coins, where each coin can be any amount of XCH. When spending a coin (making a transaction), you have to spend the entire amount, and split that coin into multiple outputs, called coin additions. One addition is to the recipient of the transaction, and the other one is to you, as change. The change usually goes to a new address, so you will not see it in your normal address on Chia explorer, but your wallet will keep track of it and include it in the balance. Each block in Chia is a list of removals (coins spent) and additions (coins created). There are no transactions in the blockchain, which is why you cannot lookup transactions in the block explorers.

HD or Hierarchical Deterministic keys are a type of public key/private key scheme where one private key can have a nearly infinite number of different public keys (and therefor wallet receive addresses) that will all ultimately come back to and be spendable by a single private key.

Small reorgs in Chia are possible, though rare. In order to be confident that your transaction won't be reorged, you should wait around six blocks, or two minutes, after the first confirmation. More details are available in our consensus documentation.

Try the following options:

To delete your wallet DB follow these steps:

Your pending transaction can take a few minutes if blocks are full. If it's not confirmed after a while, your pending transaction might be stuck. Try the following steps:

Known problem: After your wallet is resynced, any previous outgoing transaction will appear as incoming transaction at the block height you made the outgoing transaction.

Visit chia.net/buy-xch for instructions on buying Chia with USDS and offers using the Chia light wallet and Offers.

There are also several exchanges that offer XCH. You can see a list of exchanges supporting XCH here. This list is for informational purposes only. It is up to the reader to do their own research on the best exchange for their needs.

If you were running the light wallet beta app (v1.2.11 dev 265) and youve upgraded to the latest beta (v1.2.12+), you can get your offer history and your CAT wallets back by following these instructions:

This is because of the newly integrated light wallet client sync. The wallet will sync through the light wallet sync while the full node syncs up in the background. Once the full node is synced up, then the wallet will sync primarily through the local trusted full node.

If youve lost your offer history and want to cancel those offers but cant access them, then the only way to cancel the offer would be to send yourself a transaction with the CAT tokens that were part of the offer.

The wallet no longer automatically adds unknown CATs wallets for CATs that may have been airdropped to your wallet. This is to help ensure that syncing doesnt slow down with all the additional CATs that could suddenly show up. It is recommended that you use a tail database to look up and add. We understand that this will add some extra work to know which CATs to add wallets for and set them up manually. We do hope to improve upon this experience Soon

This is the way our tools work today. Just make sure when you submit feedback or an issue in Github to use the app version (1.2.12 dev269) when reporting it so we know exactly which version you're running.

Follow this link:

FAQ Chia-Network/chia-blockchain Wiki GitHub

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See the latest updates to our nootropics blog below to begin exploring the vast world of nootropics and dietary supplements.

THE TOP 5 MILK THISTLE HEALTH BENEFITSMilk thistle, orSilybum marianum,is a plant which grows all over the world...

THE TOP BENEFITS OF TAURINELet us dispel the popular Taurine myth...

HOW TO BOOST YOUR IMMUNE SYSTEM WITH THE BEST IMMUNE SUPPLEMENTSWith winter fast approaching, and in some parts of the world already in full-swing temperature-wise, we should start supporting our immune health...

GUIDE TO THE TOP NATURAL NOOTROPICS OF 2018With so many options to choose from, and many more arriving on the market each day, venturing into the vast world of nootropics...

NIGELLA SATIVA: THE TOP HEALTH BENEFITS OF BLACK SEED OIL EXTRACTNigella Sativa Extract, also known as Black Seed Extract, Black Seed Oil, Nigella Sativa Oil, Black Cumin, or Kalonji, is a seed extract that comes from a plant that is...

MAGNESIUM GLYCINATE VS. L-THREONATE: WHICH IS THE BEST MAGNESIUM SUPPLEMENT? Recent research has indicated that many individuals are currently deficient in magnesium. In fact, the numbers are a little bit shocking...

7,8 DIHYDROXYFLAVONE: A BRAIN HEALTH SUPPLEMENT THAT MAY SUPPORT NEUROPLASTICITY 7,8-Dihydroxyflavone, also known as 7,8-DHF, is a naturally occurring flavone...

CREATINE: A NOOTROPIC FOR BODYBUILDERS, ATHLETES, VEGANS, AND VEGETARIANS Creatine is an important molecule that is produced by our bodies and consumed through our diet...

HOW TO FIND THE BEST CURCUMIN SUPPLEMENT AND WHAT YOU NEED TO KNOW BEFORE YOU BUY Curcumin is a diarylheptanoid which is found in turmeric rhizomes...

COMPARING RHODIOLA ROSEA EXTRACTS: ROSAVINS VS. SALIDROSIDE Rhodiola rosea, more commonly known as golden root or rose root...

BERBERINE: A LOOK AT THE POTENTIAL BENEFITS OF THIS VERSATILE SUPPLEMENT Berberine is a bright yellow alkaloid that is found in a variety of plants...

HERICIUM ERINACEUS: WHICH IS THE BEST LION'S MANE MUSHROOM FOR YOU? Hericium erinaceus, also known as lions mane mushroom...

NITRIC OXIDE SUPPLEMENTS REVIEWED: L-CITRULLINE, AGMATINE AND AAKG Nitric oxide is a very interesting neurotransmitter within the body...

GANODERMA LUCIDUM: WHICH IS THE BEST RED REISHI MUSHROOM FOR YOU? We are often asked which Red Reishi extract is best...

COMPREHENSIVE GUIDE TO THE BEST ANTI-AGING SUPPLEMENTS Let's facilitate a healthy aging process, rather than trying to completely halt it...

WHICH IS THE BEST CORDYCEPS MUSHROOM FOR YOU? Did you know not all Cordyceps mushroom extracts are made the same way?

BACOPA MONNIERI: BACOGNIZE VS. SYNAPSA - WHICH AYURVEDIC HERB IS RIGHT FOR YOU? Commonly known as the waterhyssop or brahmi...

THE NOOTROPIC SYNERGY OF CAFFEINE AND L-THEANINE One of the most popular natural nootropic stacks is a simple combination of L-theanine and caffeine...

L-CITRULLINE VS. L-CITRULLINE DL-MALATE: WHICH IS BEST? L-citrulline is one of three dietary amino acids involved in the urea cycle...

SHILAJIT: A LOOK AT THIS AMAZING AYURVEDIC SUPPLEMENT Shilajit is a sticky, tar-like substance often appearing dark brown in color...

ULTIMATE GUIDE TO CHOLINE SUPPLEMENTS Choline is an essential nutrient that is found in a variety of foods...

ULTIMATE GUIDE TO KRILL AND FISH OIL SUPPLEMENTS Fish oil supplements are going to provide a very solid base to build a nootropics stack upon...

WHAT YOU MIGHT NOT KNOW ABOUT PANAX GINSENG SUPPLEMENTS Ginseng is one of the most well known herbs in the world...

Ayurveda|Adaptogens |Amino Acids | Choline Supplements |FitnessSupplements | Immune Support | Metabolism Supplements|Mushroom Extracts |Natural Plant Extracts| Natural Nootropic Capsules |NaturalPainSupport |Patented Nootropic Extracts|Sleep Support Supplements|Softgels |Solutions + Sublinguals|Enteric Coated Tablets|Nootropic Samples

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Nootropics – reddit

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I work at a supplement testing laboratory where my specialty is HPLC. Every single product that has come through the door with Ashwagandha on the label from these 2 brands is insanely low in withanolide content. Orders of magnitude low. I just got Sensorils HPLC method and I'm seeing how they quantify their product and they are lying liars, like how NBC Dateline with Chris Hansen did with that dry labbing lab in 2012. They aren't quantifying anything, literally making up numbers. Yeah that's right, I'm accusing Sensoril of lying about what is in their product and I have proof, not just in their garbage method but in the dozens of clients samples I've tested that contain literal fairy dust amounts of actives. These products contain no plant DNA either so there's no way you can positively identify that Ashwagandha is in a product.

What's more, I know that there is at least one independent laboratory that is advertising their ability to test Ashwagandha and I have proof that they are literally making up numbers, I sent them a sample with a fake spec and they hit the fake spec right on the money. I have been a chemist for 18 years now and I am extremely reserved about accusing other institutions/laboratories of misconduct but I am 100% confident there is major fuckery happening in ashwagandha manufacturing and testing.

Today I learned the makers of KSM-66 are suing Sensoril because Sensoril is essentially copying their product. But both products are worthless extracts. Sensoril and KSM-66 say their product are standardized to withanolide glycosides and that their products are aqueous extracts which is horseshit, withanolide glycosides are not water soluble.

These companies are advertising hearty soup but delivering hot ham water.

And no, I have no conflict of interest, I don't have a financial stake in any of this.

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Nootropics - reddit

Nootropics: Types, safety, and risks of smart drugs – Medical News Today

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Nootropics, or smart drugs, are a class of substances that can boost brain performance. They are sometimes called cognition enhancers or memory enhancing substances.

Prescription nootropics are medications that have stimulant effects. They can counteract the symptoms of medical conditions such as attention deficit hyperactivity disorder (ADHD), narcolepsy, or Alzheimers disease.

Nonprescription substances that can enhance brain performance or focus such as caffeine and creatine are also considered nootropics. They do not treat diseases but may have some effects on thinking, memory, or other mental functions.

This article looks at prescription and nonprescription smart drugs, including their uses, side effects, and safety warnings.

A doctor may prescribe a nootropic to treat a medical condition. Usually, the drug is a type of stimulant, such as an amphetamine, that can help treat ADHD, narcolepsy, dementia, or a similar condition.

Prescription nootropics include:

While these can be effective in treating specific medical conditions, a person should not take them without a prescription.

Like any prescription medications, they carry risks of side effects and interactions, and a person should only take them under a doctors care.

Common side effects of prescription nootropics include:

Some evidence suggests that people who use prescription nootropics to improve brain function have a higher risk of impulsive behaviors, such as risky sexual practices.

Healthcare providers should work closely with people taking prescription nootropics to manage any side effects and monitor their condition.

The term nootropic can also refer to natural or synthetic supplements that boost mental performance. The following sections discuss nootropics that do not require a prescription.

Many people consume beverages that contain caffeine, such as coffee or tea, because of their stimulant effects. Studies suggest that caffeine is safe for most people in moderate amounts.

Having a regular cup of coffee or tea may be a good way to boost mental focus. However, extreme amounts of caffeine may not be safe.

The Food and Drug Administration (FDA) recommend that people consume no more than 400 milligrams (mg) of caffeine a day. This is the amount in 45 cups of coffee.

Caffeine pills and powders can contain extremely high amounts of the stimulant. Taking them can lead to a caffeine overdose and even death, in rare cases.

Women who are pregnant or may become pregnant may need to limit or avoid caffeine intake. Studies have found that consuming 4 or more servings of caffeine a day is linked to a higher risk of pregnancy loss.

L-theanine is an amino acid that occurs in black and green teas. People can also take l-theanine supplements.

A 2016 review reported that l-theanine may increase alpha waves in the brain. Alpha waves may contribute to a relaxed yet alert mental state.

L-theanine may work well when paired with caffeine. Some evidence suggests that this combination helps boost cognitive performance and alertness. Anyone looking to consume l-theanine in tea should keep the FDAs caffeine guidelines in mind.

There are no dosage guidelines for l-theanine, but many supplements recommend taking 100400 mg per day.

Omega-3 fatty acids are among the most well-known and well-studied mental enhancers.

These polyunsaturated fats are found in fatty fish and fish oil supplements. This type of fat is important for brain health, and a person must get it from their diet.

Omega-3s help build membranes around the bodys cells, including the neurons. These fats are important for repairing and renewing brain cells.

A 2015 review found that omega-3 fatty acids protect against brain aging. Other research has concluded that omega-3s are important for brain and nervous system function.

However, a large analysis found no benefit for cognitive function with omega3 [polyunsaturated fatty acids] supplementation among cognitively healthy older people. The authors recommend further long term studies.

A person can get omega-3 supplements in various forms, including fish oil, krill oil, and algal oil.

These supplements carry a low risk of side effects when a person takes them as directed, but they may interact with medications that affect blood clotting. Ask a doctor before taking them.

Racetams are synthetic compounds that can affect neurotransmitters in the brain. Some nootropic racetams include:

A study conducted in rats suggests that piracetam may have neuroprotective effects.

One review states that Some of the studies suggested there may be some benefit from piracetam, but, overall, the evidence is not consistent or positive enough to support its use for dementia or cognitive impairment. Confirming this will require more research.

There is no set dosage for racetams, so a person should follow instructions and consult a healthcare provider. Overall, studies have no found adverse effects of taking racetams as directed.

Ginkgo biloba is a tree native to China, Japan, and Korea. Its leaves are available as an herbal supplement.

A 2016 study found that gingko biloba is potentially beneficial for improving brain function, but confirming this will require more research.

Ginkgo biloba may help with dementia symptoms, according to one review, which reported the effects occurring in people who took more than 200 mg per day for at least 5 months.

However, the reviews authors note that more research is needed. Also, with prescription nootropics available, ginkgo biloba may not be the most safe or effective option.

Panax ginseng is a perennial shrub that grows in China and parts of Siberia. People use its roots for medicinal purposes.

People should not confuse Panax ginseng with other types of ginseng, such as Siberian or American varieties. These are different plants with different uses.

A 2018 review reports that Panax ginseng may help prevent certain brain diseases, including Alzheimers disease, Parkinsons disease, and Huntingtons disease. It also may help with brain recovery after a stroke.

Panax ginseng interacts with many medications, so consult a doctor before taking it. A typical dosage for mental function is 100600 mg once or twice a day.

Some evidence suggests that Rhodiola rosea L., also known as rhodiola or roseroot, can help with cognitive ability.

One review reported that rhodiola may have neuroprotective effects and may help treat neurodegenerative diseases.

Another review found that rhodiola helped regulate neurotransmitters in the brain, having a positive effect on mood.

Rhodiola capsules have varying strengths. Usually, a person takes a capsule once or twice daily.

Creatine is an amino acid, which is a building block of protein. This supplement is popular among athletes because it may help improve exercise performance. It may also have some effects on mental ability.

A 2018 review found that taking creatine appears to help with short term memory and reasoning. Whether it helps the brain in other ways is unclear.

The International Society of Sports Nutrition report that creatine supplementation of up to 30 grams per day is safe for healthy people to take for 5 years.

Another 2018 review notes that there has been limited research into whether this supplement is safe and effective for adolescent athletes.

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Nootropics: Types, safety, and risks of smart drugs - Medical News Today

Fourth Amendment EPIC – Electronic Privacy Information Center

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The Fourth Amendment is one of the main constitutional privacy protections in the United States. The Fourth Amendment prohibits unreasonable searches and seizures without a warrantgenerally, law enforcement must obtain a warrant when a search would violate a persons reasonable expectation of privacy. The Fourth Amendment also requires that warrants be supported by probable cause and describe with particularity the places to be searched and persons to be seized.

The advent of the internet and other digital technologies has ushered in new issues about when police must obtain a warrant, what must support the warrant, and what the warrant must say. Recurring questions include whether exceptions to the warrant requirement developed before cell phones and the internet apply to electronic data and the point at which police use of surveillance technology interferes with individuals reasonable expectation of privacy. EPIC works to ensure that advancing technology does not erode Fourth Amendment rights, primarily by participating as a friend of the court in important Fourth Amendment case.

In two seminal casesRileyv. California(2014) andCarpenter v. United States(2018)the Supreme Court has recognized that people have a reasonable expectation of privacy in the contents of their cell phone and in their historical location information. These cases show that the Court is reluctant to extend pre-digital warrant exceptions to new technological situations.

InRiley, the Court decided that the search incident to arrest exception to the warrant requirement did not apply to cell phones. Under the traditional search-incident-to-arrest exception, law enforcement did not need a warrant to search objects on a person being arrested because the officers safety during the arrest depended on ascertaining whether the objects were weapons or contained weapons. InRiley, the Supreme Court refused to expand this exception to searches of cell phones during arrests because police do not need to look at the contents of the phone to determine whether the phone is a threat to their safety. The Court found that the warrantless search of a cell phone would be an unreasonable invasion of the persons privacy because of the vast amount of personal information it contained.

Similarly, inCarpenter, the Court found that police needed a warrant to obtain weeks-long records of peoples movements generated by their cell phones, refusing to expand the third-party exception to the warrant requirement. Under the traditional third-party exception, people have no reasonable expectation of privacy in information held by a third party. InCarpenter, law enforcement attempted to use this exception to justify obtaining cell phone tower location records from the defendants phone carrier without first getting a warrant. The Court ruled that people have a reasonable expectation of privacy in their movements over a several weeks-long period because the information creates a revealing portrait of the persons daily life.

EPICfightsto ensure that our constitutional rights are not eroded by new technologies, primarily by participating as a friend of the court in important Fourth Amendment cases.

EPIC has filed briefs in cases about whether school administrators may search throughstudents cell phoneswithout consent, whether the police may collect peoplesDNAbefore they have been convicted of a crime, whether cities may compile information about peoplese-scooterrides, and whether the police may collect a personspublic transportation recordswithout a warrant. EPIC has also intervened in cases involving the scope and methods used in searches of private information, such as whether police who have probable cause to search a cell phone for one crime may conduct awholesale searchof the phones entire contents for any crimes, whether police can search electronic dataautomatically scanned and reported by service providerswithout first obtaining a warrant, and whether law enforcement may search through phones without a warrantnear the border.

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Fourth Amendment EPIC - Electronic Privacy Information Center

What Does the Fourth Amendment Mean? | United States Courts

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Whether a particular type of search is considered reasonablein the eyes of the law,is determined by balancing two important interests. On one side of the scale is the intrusion on an individual's Fourth Amendment rights. On the other side of the scale are legitimate government interests, such as public safety.

The extent to which an individual is protected by the Fourth Amendment depends, in part, on the location of the search or seizure.Minnesota v. Carter, 525 U.S. 83 (1998).

Searches and seizures inside a home without a warrant are presumptively unreasonable.Payton v. New York, 445 U.S. 573 (1980).

However, there are some exceptions. A warrantless search may be lawful:

If an officer is given consent to search;Davis v. United States, 328 U.S. 582 (1946)If the search is incident to a lawful arrest;United States v. Robinson, 414 U.S. 218 (1973)If there is probable cause to search and exigent circumstances;Payton v. New York, 445 U.S. 573 (1980)If the items are in plain view;Maryland v. Macon, 472 U.S. 463 (1985).

When an officer observes unusual conduct which leads him reasonably to conclude that criminal activity may be afoot, the officer may briefly stop the suspicious person and make reasonable inquiries aimed at confirming or dispelling the officer's suspicions.Terry v. Ohio, 392 U.S. 1 (1968)Minnesota v. Dickerson, 508 U.S. 366 (1993)

School officials need not obtain a warrant before searching a student who is under their authority; rather, a search of a student need only be reasonable under all the circumstances.New Jersey v. TLO, 469 U.S. 325 (1985)

Where there is probable cause to believe that a vehicle contains evidence of a criminal activity, an officer may lawfully search any area of the vehicle in which the evidence might be found.Arizona v. Gant, 129 S. Ct. 1710 (2009),

An officer may conduct a traffic stop if he has reasonable suspicion that a traffic violation has occurred or that criminal activity is afoot.Berekmer v. McCarty, 468 U.S. 420 (1984),United States v. Arvizu, 534 U.S. 266 (2002).

An officer may conduct a pat-down of the driver and passengers during a lawful traffic stop; the police need not believe that any occupant of the vehicle is involved in a criminal activity.Arizona v. Johnson, 555 U.S. 323 (2009).

The use of a narcotics detection dog to walk around the exterior of a car subject to a valid traffic stop does not require reasonable, explainable suspicion.Illinois v. Cabales, 543 U.S. 405 (2005).

Special law enforcement concerns will sometimes justify highway stops without any individualized suspicion.Illinois v. Lidster, 540 U.S. 419 (2004).

An officer at an international border may conduct routine stops and searches.United States v. Montoya de Hernandez, 473 U.S. 531 (1985).

A state may use highway sobriety checkpoints for the purpose of combating drunk driving.Michigan Dept. of State Police v. Sitz, 496 U.S. 444 (1990).

A state may set up highway checkpoints where the stops are brief and seek voluntary cooperation in the investigation of a recent crime that has occurred on that highway.Illinois v. Lidster, 540 U.S. 419 (2004).

However, a state may not use a highway checkpoint program whose primary purpose is the discovery and interdiction of illegal narcotics.City of Indianapolis v. Edmond, 531 U.S. 32 (2000).

DISCLAIMER: These resources are created by the Administrative Office of the U.S. Courts for educational purposes only. They may not reflect the current state of the law, and are not intended to provide legal advice, guidance on litigation, or commentary on any pending case or legislation.

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What Does the Fourth Amendment Mean? | United States Courts

Nano-traditional Chinese medicine: a promising strategy and its recent …

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Traditional Chinese Medicine (TCM) has been applied to the prevention and treatment of numerous diseases and has an irreplaceable role in rehabilitation and health care. However, the application of TCMs is drastically limited by their defects, such as single administration, poor water solubility, low bioavailability, and weak targeting capability. Recently, nanoparticles have been extensively used in resolving pharmaceutical obstacles in consideration of their large specific surface area, strong targeting capability, good sustained-release effect, etc. In this review, we first describe the limitations of TCM ingredients and two significant forms of nanotechnology applied in TCM, nanometerization of TCMs and nano-drug delivery systems for TCMs. Then, we discuss the preparation methods of nanometerization: mechanical crushing, spray drying, and high-pressure homogenization, which have been utilized to conquer the various weaknesses of TCMs. Then, recent advances in nano-drug delivery systems for TCM ingredients are discussed, including lipid-based nanocarriers, polymeric nanoparticles, inorganic nanocarriers, hybrid nanoparticles, and TCM self-assembled nanoparticles. Finally, the future challenges and perspectives of TCM formula complexity and the limitations of nanocarriers are also discussed. Better understanding the function of nanotechnology in TCM will help to modernize Chinese medicine and broaden the application of nano-TCM in the clinic.

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Nano-traditional Chinese medicine: a promising strategy and its recent ...

Nanomedicine – Wikipedia

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Medical application of nanotechnology

Nanomedicine is the medical application of nanotechnology.[1] Nanomedicine ranges from the medical applications of nanomaterials and biological devices, to nanoelectronic biosensors, and even possible future applications of molecular nanotechnology such as biological machines. Current problems for nanomedicine involve understanding the issues related to toxicity and environmental impact of nanoscale materials (materials whose structure is on the scale of nanometers, i.e. billionths of a meter).[2][3]

Functionalities can be added to nanomaterials by interfacing them with biological molecules or structures. The size of nanomaterials is similar to that of most biological molecules and structures; therefore, nanomaterials can be useful for both in vivo and in vitro biomedical research and applications. Thus far, the integration of nanomaterials with biology has led to the development of diagnostic devices, contrast agents, analytical tools, physical therapy applications, and drug delivery vehicles.

Nanomedicine seeks to deliver a valuable set of research tools and clinically useful devices in the near future.[4][5] The National Nanotechnology Initiative expects new commercial applications in the pharmaceutical industry that may include advanced drug delivery systems, new therapies, and in vivo imaging.[6] Nanomedicine research is receiving funding from the US National Institutes of Health Common Fund program, supporting four nanomedicine development centers.[7]

Nanomedicine sales reached $16 billion in 2015, with a minimum of $3.8 billion in nanotechnology R&D being invested every year. Global funding for emerging nanotechnology increased by 45% per year in recent years, with product sales exceeding $1 trillion in 2013.[8] As the nanomedicine industry continues to grow, it is expected to have a significant impact on the economy.

Nanotechnology has provided the possibility of delivering drugs to specific cells using the nanoparticles.[9][10] The overall drug consumption and side-effects may be lowered significantly by depositing the active pharmaceutical agent in the morbid region only and in no higher dose than needed. Targeted drug delivery is intended to reduce the side effects of drugs with concomitant decreases in consumption and treatment expenses. Additionally, targeted drug drug delivery reduces the side effect possessed by crude drug via minimizing undesired exposure to the healthy cells. Drug delivery focuses on maximizing bioavailability both at specific places in the body and over a period of time. This can potentially be achieved by molecular targeting by nanoengineered devices.[11][12] A benefit of using nanoscale for medical technologies is that smaller devices are less invasive and can possibly be implanted inside the body, plus biochemical reaction times are much shorter. These devices are faster and more sensitive than typical drug delivery.[13] The efficacy of drug delivery through nanomedicine is largely based upon: a) efficient encapsulation of the drugs, b) successful delivery of drug to the targeted region of the body, and c) successful release of the drug.[14] Several nano-delivery drugs were on the market by 2019.[15]

Drug delivery systems, lipid-[16] or polymer-based nanoparticles, can be designed to improve the pharmacokinetics and biodistribution of the drug.[17][18][19] However, the pharmacokinetics and pharmacodynamics of nanomedicine is highly variable among different patients.[20] When designed to avoid the body's defence mechanisms,[21] nanoparticles have beneficial properties that can be used to improve drug delivery. Complex drug delivery mechanisms are being developed, including the ability to get drugs through cell membranes and into cell cytoplasm. Triggered response is one way for drug molecules to be used more efficiently. Drugs are placed in the body and only activate on encountering a particular signal. For example, a drug with poor solubility will be replaced by a drug delivery system where both hydrophilic and hydrophobic environments exist, improving the solubility.[22] Drug delivery systems may also be able to prevent tissue damage through regulated drug release; reduce drug clearance rates; or lower the volume of distribution and reduce the effect on non-target tissue. However, the biodistribution of these nanoparticles is still imperfect due to the complex host's reactions to nano- and microsized materials[21] and the difficulty in targeting specific organs in the body. Nevertheless, a lot of work is still ongoing to optimize and better understand the potential and limitations of nanoparticulate systems. While advancement of research proves that targeting and distribution can be augmented by nanoparticles, the dangers of nanotoxicity become an important next step in further understanding of their medical uses.[23] The toxicity of nanoparticles varies, depending on size, shape, and material. These factors also affect the build-up and organ damage that may occur. Nanoparticles are made to be long-lasting, but this causes them to be trapped within organs, specifically the liver and spleen, as they cannot be broken down or excreted. This build-up of non-biodegradable material has been observed to cause organ damage and inflammation in mice.[24] Magnetic targeted delivery of magnetic nanoparticles to the tumor site under the influence of inhomogeneous stationary magnetic fields may lead to enhanced tumor growth. In order to circumvent the pro-tumorigenic effects, alternating electromagnetic fields should be used.[25]

Nanoparticles are under research for their potential to decrease antibiotic resistance or for various antimicrobial uses.[26][27][28][29] Nanoparticles might also be used to circumvent multidrug resistance (MDR) mechanisms.[9]

Advances in lipid nanotechnology were instrumental in engineering medical nanodevices and novel drug delivery systems, as well as in developing sensing applications.[30] Another system for microRNA delivery under preliminary research is nanoparticles formed by the self-assembly of two different microRNAs deregulated in cancer.[31] One potential application is based on small electromechanical systems, such as nanoelectromechanical systems being investigated for the active release of drugs and sensors for possible cancer treatment with iron nanoparticles or gold shells.[32]

Some nanotechnology-based drugs that are commercially available or in human clinical trials include:

In vivo imaging is another area where tools and devices are being developed.[39] Using nanoparticle contrast agents, images such as ultrasound and MRI have a favorable distribution and improved contrast. In cardiovascular imaging, nanoparticles have potential to aid visualization of blood pooling, ischemia, angiogenesis, atherosclerosis, and focal areas where inflammation is present.[39]

The small size of nanoparticles endows them with properties that can be very useful in oncology, particularly in imaging.[9] Quantum dots (nanoparticles with quantum confinement properties, such as size-tunable light emission), when used in conjunction with MRI (magnetic resonance imaging), can produce exceptional images of tumor sites. Nanoparticles of cadmium selenide (quantum dots) glow when exposed to ultraviolet light. When injected, they seep into cancer tumors. The surgeon can see the glowing tumor, and use it as a guide for more accurate tumor removal. These nanoparticles are much brighter than organic dyes and only need one light source for excitation. This means that the use of fluorescent quantum dots could produce a higher contrast image and at a lower cost than today's organic dyes used as contrast media. The downside, however, is that quantum dots are usually made of quite toxic elements, but this concern may be addressed by use of fluorescent dopants.[40]

Tracking movement can help determine how well drugs are being distributed or how substances are metabolized. It is difficult to track a small group of cells throughout the body, so scientists used to dye the cells. These dyes needed to be excited by light of a certain wavelength in order for them to light up. While different color dyes absorb different frequencies of light, there was a need for as many light sources as cells. A way around this problem is with luminescent tags. These tags are quantum dots attached to proteins that penetrate cell membranes.[40] The dots can be random in size, can be made of bio-inert material, and they demonstrate the nanoscale property that color is size-dependent. As a result, sizes are selected so that the frequency of light used to make a group of quantum dots fluoresce is an even multiple of the frequency required to make another group incandesce. Then both groups can be lit with a single light source. They have also found a way to insert nanoparticles[41] into the affected parts of the body so that those parts of the body will glow showing the tumor growth or shrinkage or also organ trouble.[42]

Nanotechnology-on-a-chip is one more dimension of lab-on-a-chip technology. Magnetic nanoparticles, bound to a suitable antibody, are used to label specific molecules, structures or microorganisms. In particular silica nanoparticles are inert from the photophysical point of view and might accumulate a large number of dye(s) within the nanoparticle shell.[43] Gold nanoparticles tagged with short segments of DNA can be used for detection of genetic sequence in a sample. Multicolor optical coding for biological assays has been achieved by embedding different-sized quantum dots into polymeric microbeads. Nanopore technology for analysis of nucleic acids converts strings of nucleotides directly into electronic signatures.[citation needed]

Sensor test chips containing thousands of nanowires, able to detect proteins and other biomarkers left behind by cancer cells, could enable the detection and diagnosis of cancer in the early stages from a few drops of a patient's blood.[44] Nanotechnology is helping to advance the use of arthroscopes, which are pencil-sized devices that are used in surgeries with lights and cameras so surgeons can do the surgeries with smaller incisions. The smaller the incisions the faster the healing time which is better for the patients. It is also helping to find a way to make an arthroscope smaller than a strand of hair.[45]

Research on nanoelectronics-based cancer diagnostics could lead to tests that can be done in pharmacies. The results promise to be highly accurate and the product promises to be inexpensive. They could take a very small amount of blood and detect cancer anywhere in the body in about five minutes, with a sensitivity that is a thousand times better a conventional laboratory test. These devices are built with nanowires to detect cancer proteins; each nanowire detector is primed to be sensitive to a different cancer marker.[32] The biggest advantage of the nanowire detectors is that they could test for anywhere from ten to one hundred similar medical conditions without adding cost to the testing device.[46] Nanotechnology has also helped to personalize oncology for the detection, diagnosis, and treatment of cancer. It is now able to be tailored to each individual's tumor for better performance. They have found ways that they will be able to target a specific part of the body that is being affected by cancer.[47]

In contrast to dialysis, which works on the principle of the size related diffusion of solutes and ultrafiltration of fluid across a semi-permeable membrane, the purification with nanoparticles allows specific targeting of substances.[48] Additionally larger compounds which are commonly not dialyzable can be removed.[49]

The purification process is based on functionalized iron oxide or carbon coated metal nanoparticles with ferromagnetic or superparamagnetic properties.[50] Binding agents such as proteins,[48] antibiotics,[51] or synthetic ligands[52] are covalently linked to the particle surface. These binding agents are able to interact with target species forming an agglomerate. Applying an external magnetic field gradient allows exerting a force on the nanoparticles. Hence the particles can be separated from the bulk fluid, thereby cleaning it from the contaminants.[53][54]

The small size (< 100nm) and large surface area of functionalized nanomagnets leads to advantageous properties compared to hemoperfusion, which is a clinically used technique for the purification of blood and is based on surface adsorption. These advantages are high loading and accessible for binding agents, high selectivity towards the target compound, fast diffusion, small hydrodynamic resistance, and low dosage.[55]

Nanotechnology may be used as part of tissue engineering to help reproduce or repair or reshape damaged tissue using suitable nanomaterial-based scaffolds and growth factors. Tissue engineering if successful may replace conventional treatments like organ transplants or artificial implants. Nanoparticles such as graphene, carbon nanotubes, molybdenum disulfide and tungsten disulfide are being used as reinforcing agents to fabricate mechanically strong biodegradable polymeric nanocomposites for bone tissue engineering applications. The addition of these nanoparticles in the polymer matrix at low concentrations (~0.2 weight%) leads to significant improvements in the compressive and flexural mechanical properties of polymeric nanocomposites.[56][57] Potentially, these nanocomposites may be used as a novel, mechanically strong, light weight composite as bone implants.[citation needed]

For example, a flesh welder was demonstrated to fuse two pieces of chicken meat into a single piece using a suspension of gold-coated nanoshells activated by an infrared laser. This could be used to weld arteries during surgery.[58]Another example is nanonephrology, the use of nanomedicine on the kidney.

Neuro-electronic interfacing is a visionary goal dealing with the construction of nanodevices that will permit computers to be joined and linked to the nervous system. This idea requires the building of a molecular structure that will permit control and detection of nerve impulses by an external computer. A refuelable strategy implies energy is refilled continuously or periodically with external sonic, chemical, tethered, magnetic, or biological electrical sources, while a non-refuelable strategy implies that all power is drawn from internal energy storage which would stop when all energy is drained. A nanoscale enzymatic biofuel cell for self-powered nanodevices have been developed that uses glucose from biofluids including human blood and watermelons.[59] One limitation to this innovation is the fact that electrical interference or leakage or overheating from power consumption is possible. The wiring of the structure is extremely difficult because they must be positioned precisely in the nervous system. The structures that will provide the interface must also be compatible with the body's immune system.[60]

Molecular nanotechnology is a speculative subfield of nanotechnology regarding the possibility of engineering molecular assemblers, machines which could re-order matter at a molecular or atomic scale.[citation needed] Nanomedicine would make use of these nanorobots, introduced into the body, to repair or detect damages and infections. Molecular nanotechnology is highly theoretical, seeking to anticipate what inventions nanotechnology might yield and to propose an agenda for future inquiry. The proposed elements of molecular nanotechnology, such as molecular assemblers and nanorobots are far beyond current capabilities.[1][60][61] Future advances in nanomedicine could give rise to life extension through the repair of many processes thought to be responsible for aging. K. Eric Drexler, one of the founders of nanotechnology, postulated cell repair machines, including ones operating within cells and utilizing as yet hypothetical molecular machines, in his 1986 book Engines of Creation, with the first technical discussion of medical nanorobots by Robert Freitas appearing in 1999.[1] Raymond Kurzweil, a futurist and transhumanist, stated in his book The Singularity Is Near that he believes that advanced medical nanorobotics could completely remedy the effects of aging by 2030.[62] According to Richard Feynman, it was his former graduate student and collaborator Albert Hibbs who originally suggested to him (c.1959) the idea of a medical use for Feynman's theoretical micromachines (see nanotechnology). Hibbs suggested that certain repair machines might one day be reduced in size to the point that it would, in theory, be possible to (as Feynman put it) "swallow the doctor". The idea was incorporated into Feynman's 1959 essay There's Plenty of Room at the Bottom.[63]

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Nanotechnology Timeline | National Nanotechnology Initiative

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This timeline features Premodern example of nanotechnology, as well as Modern Era discoveries and milestones in the field of nanotechnology.

Early examples of nanostructured materials were based on craftsmens empirical understanding and manipulation of materials. Use of high heat was one common step in their processes to produce these materials with novel properties.

The Lycurgus Cup at the British Museum, lit from the outside (left) and from the inside (right)

4th Century: The Lycurgus Cup (Rome) is an example of dichroic glass; colloidal gold and silver in the glass allow it to look opaque green when lit from outside but translucent red when light shines through the inside. (Images at left.)

9th-17th Centuries: Glowing, glittering luster ceramic glazes used in the Islamic world, and later in Europe, contained silver or copper or other metallic nanoparticles. (Image at right.)

6th-15th Centuries: Vibrant stained glass windows in European cathedrals owed their rich colors to nanoparticles of gold chloride and other metal oxides and chlorides; gold nanoparticles also acted as photocatalytic air purifiers. (Image at left.)

13th-18th Centuries: Damascus saber blades contained carbon nanotubes and cementite nanowiresan ultrahigh-carbon steel formulation that gave them strength, resilience, the ability to hold a keen edge, and a visible moir pattern in the steel that give the blades their name. (Images below.)

These are based on increasingly sophisticated scientific understanding and instrumentation, as well as experimentation.

1857: Michael Faraday discovered colloidal ruby gold, demonstrating that nanostructured gold under certain lighting conditions produces different-colored solutions.

1936: Erwin Mller, working at Siemens Research Laboratory, invented the field emission microscope, allowing near-atomic-resolution images of materials.

1947: John Bardeen, William Shockley, and Walter Brattain at Bell Labs discovered the semiconductor transistor and greatly expanded scientific knowledge of semiconductor interfaces, laying the foundation for electronic devices and the Information Age.

1950: Victor La Mer and Robert Dinegar developed the theory and a process for growing monodisperse colloidal materials. Controlled ability to fabricate colloids enables myriad industrial uses such as specialized papers, paints, and thin films, even dialysis treatments.

1951: Erwin Mller pioneered the field ion microscope, a means to image the arrangement of atoms at the surface of a sharp metal tip; he first imaged tungsten atoms.

1956: Arthur von Hippel at MIT introduced many concepts ofand coined the termmolecular engineering as applied to dielectrics, ferroelectrics, and piezoelectrics

1958: Jack Kilby of Texas Instruments originated the concept of, designed, and built the first integrated circuit, for which he received the Nobel Prize in 2000. (Image at left.)

1959: Richard Feynman of the California Institute of Technology gave what is considered to be the first lecture on technology and engineering at the atomic scale, "There's Plenty of Room at the Bottom" at an American Physical Society meeting at Caltech. (Image at right.)

1965: Intel co-founder Gordon Moore described in Electronics magazine several trends he foresaw in the field of electronics. One trend now known as Moores Law, described the density of transistors on an integrated chip (IC) doubling every 12 months (later amended to every 2 years). Moore also saw chip sizes and costs shrinking with their growing functionalitywith a transformational effect on the ways people live and work. That the basic trend Moore envisioned has continued for 50 years is to a large extent due to the semiconductor industrys increasing reliance on nanotechnology as ICs and transistors have approached atomic dimensions.1974: Tokyo Science University Professor Norio Taniguchi coined the term nanotechnology to describe precision machining of materials to within atomic-scale dimensional tolerances. (See graph at left.)

1981: Gerd Binnig and Heinrich Rohrer at IBMs Zurich lab invented the scanning tunneling microscope, allowing scientists to "see" (create direct spatial images of) individual atoms for the first time. Binnig and Rohrer won the Nobel Prize for this discovery in 1986.

1981: Russias Alexei Ekimov discovered nanocrystalline, semiconducting quantum dots in a glass matrix and conducted pioneering studies of their electronic and optical properties.

1985: Rice University researchers Harold Kroto, Sean OBrien, Robert Curl, and Richard Smalley discovered the Buckminsterfullerene (C60), more commonly known as the buckyball, which is a molecule resembling a soccer ball in shape and composed entirely of carbon, as are graphite and diamond. The team was awarded the 1996 Nobel Prize in Chemistry for their roles in this discovery and that of the fullerene class of molecules more generally. (Artist's rendering at right.)

1985: Bell Labss Louis Brus discovered colloidal semiconductor nanocrystals (quantum dots), for which he shared the 2008 Kavli Prize in Nanotechnology.

1986: Gerd Binnig, Calvin Quate, and Christoph Gerber invented the atomic force microscope, which has the capability to view, measure, and manipulate materials down to fractions of a nanometer in size, including measurement of various forces intrinsic to nanomaterials.

1989:Don Eigler and Erhard Schweizer at IBM's Almaden Research Center manipulated 35 individual xenon atoms to spell out the IBM logo. This demonstration of the ability to precisely manipulate atoms ushered in the applied use of nanotechnology. (Image at left.)

1990s: Early nanotechnology companies began to operate, e.g., Nanophase Technologies in 1989, Helix Energy Solutions Group in 1990, Zyvex in 1997, Nano-Tex in 1998.

1991: Sumio Iijima of NEC is credited with discovering the carbon nanotube (CNT), although there were early observations of tubular carbon structures by others as well. Iijima shared the Kavli Prize in Nanoscience in 2008 for this advance and other advances in the field. CNTs, like buckyballs, are entirely composed of carbon, but in a tubular shape. They exhibit extraordinary properties in terms of strength, electrical and thermal conductivity, among others. (Image below.)

1992: C.T. Kresge and colleagues at Mobil Oil discovered the nanostructured catalytic materials MCM-41 and MCM-48, now used heavily in refining crude oil as well as for drug delivery, water treatment, and other varied applications.

1993: Moungi Bawendi of MIT invented a method for controlled synthesis of nanocrystals (quantum dots), paving the way for applications ranging from computing to biology to high-efficiency photovoltaics and lighting. Within the next several years, work by other researchers such as Louis Brus and Chris Murray also contributed methods for synthesizing quantum dots.

1998: The Interagency Working Group on Nanotechnology (IWGN) was formed under the National Science and Technology Council to investigate the state of the art in nanoscale science and technology and to forecast possible future developments. The IWGNs study and report, Nanotechnology Research Directions: Vision for the Next Decade (1999) defined the vision for and led directly to formation of the U.S. National Nanotechnology Initiative in 2000.

1999: Cornell University researchers Wilson Ho and Hyojune Lee probed secrets of chemical bonding by assembling a molecule [iron carbonyl Fe(CO)2] from constituent components [iron (Fe) and carbon monoxide (CO)] with a scanning tunneling microscope. (Image at left.)

1999: Chad Mirkin at Northwestern University invented dip-pen nanolithography (DPN), leading to manufacturable, reproducible writing of electronic circuits as well as patterning of biomaterials for cell biology research, nanoencryption, and other applications. (Image below right.)

1999early 2000s: Consumer products making use of nanotechnology began appearing in the marketplace, including lightweight nanotechnology-enabled automobile bumpers that resist denting and scratching, golf balls that fly straighter, tennis rackets that are stiffer (therefore, the ball rebounds faster), baseball bats with better flex and "kick," nano-silver antibacterial socks, clear sunscreens, wrinkle- and stain-resistant clothing, deep-penetrating therapeutic cosmetics, scratch-resistant glass coatings, faster-recharging batteries for cordless electric tools, and improved displays for televisions, cell phones, and digital cameras.

2000: President Clinton launched the National Nanotechnology Initiative (NNI) to coordinate Federal R&D efforts and promote U.S. competitiveness in nanotechnology. Congress funded the NNI for the first time in FY2001. The NSET Subcommittee of the NSTC was designated as the interagency group responsible for coordinating the NNI.

2003: Congress enacted the 21st Century Nanotechnology Research and Development Act (P.L. 108-153). The act provided a statutory foundation for the NNI, established programs, assigned agency responsibilities, authorized funding levels, and promoted research to address key issues.

2003: Naomi Halas, Jennifer West, Rebekah Drezek, and Renata Pasqualin at Rice University developed gold nanoshells, which when tuned in size to absorb near-infrared light, serve as a platform for the integrated discovery, diagnosis, and treatment of breast cancer without invasive biopsies, surgery, or systemically destructive radiation or chemotherapy.2004: The European Commission adopted the Communication Towards a European Strategy for Nanotechnology, COM(2004) 338, which proposed institutionalizing European nanoscience and nanotechnology R&D efforts within an integrated and responsible strategy, and which spurred European action plans and ongoing funding for nanotechnology R&D. (Image at left.)

2004: Britains Royal Society and the Royal Academy of Engineering published Nanoscience and Nanotechnologies: Opportunities and Uncertainties advocating the need to address potential health, environmental, social, ethical, and regulatory issues associated with nanotechnology.

2004: SUNY Albany launched the first college-level education program in nanotechnology in the United States, the College of Nanoscale Science and Engineering.

2005: Erik Winfree and Paul Rothemund from the California Institute of Technology developed theories for DNA-based computation and algorithmic self-assembly in which computations are embedded in the process of nanocrystal growth.

2006: James Tour and colleagues at Rice University built a nanoscale car made of oligo(phenylene ethynylene) with alkynyl axles and four spherical C60 fullerene (buckyball) wheels. In response to increases in temperature, the nanocar moved about on a gold surface as a result of the buckyball wheels turning, as in a conventional car. At temperatures above 300C it moved around too fast for the chemists to keep track of it! (Image at left.)

2007: Angela Belcher and colleagues at MIT built a lithium-ion battery with a common type of virus that is nonharmful to humans, using a low-cost and environmentally benign process. The batteries have the same energy capacity and power performance as state-of-the-art rechargeable batteries being considered to power plug-in hybrid cars, and they could also be used to power personal electronic devices. (Image at right.)

2008: The first official NNI Strategy for Nanotechnology-Related Environmental, Health, and Safety (EHS) Research was published, based on a two-year process of NNI-sponsored investigations and public dialogs. This strategy document was updated in 2011, following a series of workshops and public review.

20092010: Nadrian Seeman and colleagues at New York University createdseveral DNA-like robotic nanoscale assembly devices.One is a process for creating 3D DNA structures using synthetic sequences of DNA crystals that can be programmed to self-assemble using sticky ends and placement in a set order and orientation.Nanoelectronics could benefit:the flexibility and density that 3D nanoscale components allow could enable assembly of parts that are smaller, more complex, and more closely spaced. Another Seeman creation (with colleagues at Chinas Nanjing University) is a DNA assembly line. For this work, Seeman shared the Kavli Prize in Nanoscience in 2010.

2010: IBM used a silicon tip measuring only a few nanometers at its apex (similar to the tips used in atomic force microscopes) to chisel away material from a substrate to create a complete nanoscale 3D relief map of the world one-one-thousandth the size of a grain of saltin 2 minutes and 23 seconds. This activity demonstrated a powerful patterning methodology for generating nanoscale patterns and structures as small as 15 nanometers at greatly reduced cost and complexity, opening up new prospects for fields such as electronics, optoelectronics, and medicine. (Image below.)

2011:The NSET Subcommittee updated both the NNI Strategic Plan and the NNI Environmental, Health, and Safety Research Strategy, drawing on extensive input from public workshops and online dialog with stakeholders from Government, academia, NGOs, and the public, and others.

2012: The NNI launched two more Nanotechnology Signature Initiatives (NSIs)--Nanosensors and the Nanotechnology Knowledge Infrastructure (NKI)--bringing the total to five NSIs.

2013: -The NNI starts the next round of Strategic Planning, starting with the Stakeholder Workshop. -Stanford researchers develop the first carbon nanotube computer.

2014: -The NNI releases the updated 2014 Strategic Plan. -The NNI releases the 2014 Progress Review on the Coordinated Implementation of the NNI 2011 Environmental, Health, and Safety Research Strategy.

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Nano Medicine: Meaning, Advantages and Disadvantages – BioTechnology Notes

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In this article we will discuss about Nano Medicine:- 1. Meaning of Nano Medicine 2. Advantages of Nano Medicine 3. Disadvantages.

The application of nanotechnology in medicine is often referred to as Nano medicine. Nano medicine is the preservation and improvement of human health using molecular tools and molecular knowledge of the human body. It covers areas such as nanoparticle drug delivery and possible future applications of molecular nanotechnology (MNT) and Nano-vaccinology.

The human body is comprised of molecules. Hence, the availability of molecular nanotechnology will permit dramatic progress in human medical services. More than just an extension of molecular medicine, Nano medicine will help us understand how the biological machinery inside living cells operates at the Nano scale so that it can be employed in molecular machine systems to address complicated medical conditions such as cancer, AIDS, ageing and thereby bring about significant improvement and extension of natural human biological structure and function at the molecular scale.

Nano medical approaches to drug delivery centre on developing Nano scale particles or molecules to improve drug bioavailability that refers to the presence of drug molecules in the body part where they are actually needed and will probably do the most good. It is all about targeting the molecules and delivering drugs with cell precision.

The use of Nano robots in medicine would totally change the world of medicine once it is realized. For instance, by introducing these Nano robots into the body damages and infections can be detected and repaired. In short it holds that capability to change the traditional approach of treating diseases and naturally occurring conditions in the human beings.

1. Advanced therapies with reduced degree of invasiveness.

2. Reduced negative effects of drugs and surgical procedures.

3. Faster, smaller and highly sensitive diagnostic tools.

4. Cost effectiveness of medicines and disease management procedures as a whole.

5. Unsolved medical problems such as cancer, benefiting from the Nano medical approach.

6. Reduced mortality and morbidity rates and increased longevity in return.

1. Lack of proper knowledge about the effect of nanoparticles on biochemical pathways and processes of human body.

2. Scientists are primarily concerned about the toxicity, characterization and exposure pathways associated with Nano medicine that might pose a serious threat to the human beings and environment.

3. The societys ethical use of Nano medicine beyond the concerned safety issues, poses a serious question to the researchers.

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Nano Medicine: Meaning, Advantages and Disadvantages - BioTechnology Notes

Air New Zealand Limited (NZSE:AIR) insiders have profited after buying stock worth NZ$3.8m last year, current gains stand at NZ$737k – Simply Wall St

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Air New Zealand Limited (NZSE:AIR) insiders have profited after buying stock worth NZ$3.8m last year, current gains stand at NZ$737k  Simply Wall St

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Air New Zealand Limited (NZSE:AIR) insiders have profited after buying stock worth NZ$3.8m last year, current gains stand at NZ$737k - Simply Wall St