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Archive for the ‘biotech/medical’ category: Page 921

Apr 23, 2022

Future Of Aging & Cellular Reprogramming | Eleanor Sheekey Ep 4

Posted by in categories: biotech/medical, chemistry, life extension, media & arts

She gives a great analogy of slowing aging versus reversing aging, and I did not realize Yamanaka Factors were not so perfect in current use.


In this video Eleanor talks about the her view on Longevity Escape Velocity and reprogramming with Yamanaka factors and some of the issues around this technology.

Continue reading “Future Of Aging & Cellular Reprogramming | Eleanor Sheekey Ep 4” »

Apr 23, 2022

Quantifying arousal and awareness in altered states of consciousness using interpretable deep learning

Posted by in categories: biotech/medical, robotics/AI

The classical neurophysiological approach for calculating PCI, power spectral density, and spectral exponent relies on many epochs to improve the reliability of statistical estimates of these indices21. However, these methods are only suitable for investigating the averaged brain states and they can only clarify general neurophysiological aspects. Machine learning (ML) allows decoding and identifying specific brain states and discriminating them from unrelated brain signals, even in a single trial in real-time22. This can potentially transform statistical results at the group level into individual predictions9. A deep neural network, which is a popular approach in ML, has been employed to classify or predict brain states using EEG data23. Particularly, a convolutional neural network (CNN) is the most extensively used technique in deep learning and has proven to be effective in the classification of EEG data24. However, a CNN has the drawback that it cannot provide information on why it made a particular prediction25. Recently, layer-wise relevance propagation (LRP) has successfully demonstrated why classifiers such as CNNs have made a specific decision26. Specifically, the relevance score resulting from the LRP indicates the contribution of each input variable to the classification or prediction decision. Thus, a high score in a particular area of an input variable implies that the classifier has made the classification or prediction using this feature. For example, neurophysiological data suggest that the left motor region is activated during right-hand motor imagery27. The LRP indicates that the neural network classifies EEG data as right-hand motor imagery because of the activity of the left motor region28. Therefore, the relevance score was higher in the left motor region than in other regions. Thus, it is possible to interpret the neurophysiological phenomena underlying the decisions of CNNs using LRP.

In this work, we develop a metric, called the explainable consciousness indicator (ECI), to simultaneously quantify the two components of consciousness—arousal and awareness—using CNN. The processed time-series EEG data were used as an input of the CNN. Unlike PCI, which relies on source modeling and permutation-based statistical analysis, ECI used event-related potentials at the sensor level for spatiotemporal dynamics and ML approaches. For a generalized model, we used the leave-one-participant-out (LOPO) approach for transfer learning, which is a type of ML that transfers information to a new participant not included in the training phase24,27. The proposed indicator is a 2D value consisting of indicators of arousal (ECIaro) and awareness (ECIawa). First, we used TMS–EEG data collected from healthy participants during NREM sleep with no subjective experience, REM sleep with subjective experience, and healthy wakefulness to consider each component of consciousness (i.e., low/high arousal and low/high awareness) with the aim to analyze correlations between the proposed ECI and the three states, namely NREM, REM, and wakefulness. Next, we measured ECI using TMS–EEG data collected under general anesthesia with ketamine, propofol, and xenon, again with the aim to measure correlation with these three anesthetics. Before anesthesia, TMS–EEG data were also recorded during healthy wakefulness. Upon awakening, healthy participants reported conscious experience during ketamine-induced anesthesia and no conscious experience during propofol-and xenon-induced anesthesia. Finally, TMS–EEG data were collected from patients with disorders of consciousness (DoC), which includes patients diagnosed as UWS and MCS patients. We hypothesized that our proposed ECI can clearly distinguish between the two components of consciousness under physiological, pharmacological, and pathological conditions.

To verify the proposed indicator, we next compared ECIawa with PCI, which is a reliable index for consciousness. Then, we applied ECI to additional resting-state EEG data acquired in the anesthetized participants and patients with DoC. We hypothesize that if CNN can learn characteristics related to consciousness, it could calculate ECI accurately even without TMS in the proposed framework. In terms of clinical applicability, it is important to use the classifier from the previous LOPO training of the old data to classify the new data (without additional training). Therefore, we computed ECI in patients with DoC using a hold-out approach29, where training data and evaluation data are arbitrarily divided, instead of cross-validation. Finally, we investigated why the classifier generated these decisions using LRP to interpret ECI30.

Apr 22, 2022

Malicious web application attacks rise

Posted by in categories: biotech/medical, nanotechnology

A large team of researchers at the University of Washington, working with colleagues from Université Montpellier and the Fred Hutchinson Cancer Research Center, has taken a major step toward the creation of an axle-rotor nanomachine. In their paper published in the journal Science, the group describes how they used DNA coding to customize E. coli to push them into creating proteins that assembled into rotors and axles.

Apr 22, 2022

Researchers take a step toward creating an axle-rotor nanomachine

Posted by in categories: biotech/medical, nanotechnology

A large team of researchers at the University of Washington, working with colleagues from Université Montpellier and the Fred Hutchinson Cancer Research Center, has taken a major step toward the creation of an axle-rotor nanomachine. In their paper published in the journal Science, the group describes how they used DNA coding to customize E. coli to push them into creating proteins that assembled into rotors and axles.

As the researchers note, molecular engines are abundant in nature, from the tails of flagellum on some bacteria to the F1 motor of ATPase. And while such examples have served as good models, attempts to harness them in nature or to create new ones in the lab have been mostly unsuccessful. This is due to the single purpose features of natural engines and the unpredictability of in synthetic attempts. In this new effort, the researchers have overcome some of the hurdles that others have faced and have taken a major step toward the creation of a molecular engine by creating two of the main parts necessary for such a device—an axle and a rotor—and even managed to connect them to each other.

To create their engine parts, the researchers first used a software program called Rosetta that allowed them to design ring-like proteins with specified diameters. They then used the data from the program to add DNA coding to in E. coli bacteria that make up proteins. Such proteins are made of chains of the amino acids—it is the sequence of them that defines the shape they will take when they spontaneously fold. The team was able to coax some of the proteins into folding into rotor shapes and others into axle shapes. They then went further by coaxing multiple proteins to fold together into rotor-axle combinations—the rudimentary parts necessary for a molecular engine.

Apr 22, 2022

Different responses to DNA damage determine ageing differences between organs

Posted by in categories: biotech/medical, life extension

Organs age differently. To investigate the basis of organ-specific ageing we systematically compared at the tissue, stem cell and organoid level two organs representing ageing extremes, from accelera…

Apr 22, 2022

Incredible video shows cancer being killed by immune system cell

Posted by in category: biotech/medical

Microscope footage shows how a fiery T cell latches onto a cancer cell in an attempt to destroy it.

Apr 22, 2022

A new genome reference index could save the gene diversity of humans

Posted by in categories: biotech/medical, genetics

Apr 22, 2022

Largest study of whole genome sequencing data reveals ‘treasure trove’ of clues about causes of cancer

Posted by in categories: biotech/medical, genetics

DNA analysis of thousands of tumors from NHS patients has found a ‘treasure trove’ of clues about the causes of cancer, with genetic mutations providing a personal history of the damage and repair processes each patient has been through.

In the biggest study of its kind, a team of scientists led by Professor Serena Nik-Zainal from Cambridge University Hospitals (CUH) and University of Cambridge, analyzed the complete genetic make-up or whole-genome sequences of more than 12,000 NHS cancer patients.

Because of the vast amount of data provided by , the researchers were able to detect patterns in the DNA of cancer—or ‘mutational signatures’—that provide clues about whether a patient has had a past exposure to environmental causes of cancer such as smoking or UV light, or has internal, cellular malfunctions.

Apr 22, 2022

Lab grown, self-sustainable muscle cells repair injury and disease, mouse study shows

Posted by in categories: biotech/medical, genetics

In proof-of-concept experiments, Johns Hopkins Medicine scientists say they have successfully cultivated human muscle stem cells capable of renewing themselves and repairing muscle tissue damage in mice, potentially advancing efforts to treat muscle injuries and muscle-wasting disorders in people.

A report on the experiments was published April 7 in Cell Stem Cell.

To make the self-renewing stem cells, the scientists began with laboratory-grown human skin cells that were genetically reprogrammed to a more primitive state in which the cells have the potential to become almost any type of cell in the body. At this point, the cells are known as induced pluripotent stem (IPS) cells, and they are mixed with a solution of standard cell growth factors and nutrients that nudge them to differentiate into specific cell types.

Apr 22, 2022

Artificial fingertip gives robots nearly humanlike touch

Posted by in categories: biotech/medical, robotics/AI

3D printed skin reacts to texture and shape like our skin.


The optical properties of mitochondrial bundles in the retina may improve how efficiently the eye captures light.

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