Comment

Comment by Dr. Krishna Kumari Challa on March 20, 2024 at 12:22pm

Combating counterfeiting: Advanced hologram protection invented

Counterfeiting of various documents, banknotes, or tickets is a common problem that can be encountered in everyday life, even when shopping. Recognizing the scale and seriousness of the problem, researchers decided to look for ways to further reduce the risk of counterfeiting by inventing a new method to produce holographic security labels.

Holograms have been used as an anti-counterfeiting tool for some time. Now, they can be seen on pharmaceutical packaging, brand labels, and even toys. Holograms are much more difficult for forgers to counterfeit than, for example, the watermarks on banknotes, as they require complex micro and nano technologies that traditional printing houses lack.

Combining two technologies has led to international recognition

To enhance the level of holographic protection against forgery and to address this worldwide problem, Lithuanian researchers from KTU Institute of Materials Science came up with the idea of combining two technologically different methods.

One of them is a dot-matrix hologram made of small dots that refract light. "Each dot, which is barely smaller than a human hair, records a periodic structure made up of lines known as a diffraction grating. It causes the light to play in a way that is visible to the observer's eye, similar to a CD or DVD. This dot-matrix hologram, although relatively faster and cheaper and used to expose large areas of the hologram, does not guarantee a very high level of protection.

This is why electron beam lithography is used to expose smaller areas of the hologram. It is a more advanced technology that allows to form high-resolution structures and is practically inaccessible to potential hologram counterfeiters.

The combination of these two techniques has received international recognition—the invention has been recognized by the US Patent and Trademark Office and the Japanese Patent Office. This protects the intellectual property created by the scientists and allows them to license it to interested companies.
In addition, holographic label technologies developed by researchers now are already widely used for metrological verification on car license plates, on the packaging of various products, and on event tickets and diplomas.
Part 1

Comment by Dr. Krishna Kumari Challa on March 20, 2024 at 11:32am

That's bad news for many materials, but it wreaks particular havoc on plastics when combined with heat. The combined effects of rising temperature and moisture create very challenging conditions for these polymers.

Xin-Feng Wei et al, Plastic pollution amplified by a warming climate, Nature Communications (2024). DOI: 10.1038/s41467-024-46127-9

part 2

Comment by Dr. Krishna Kumari Challa on March 20, 2024 at 11:31am

Global warming and plastic pollution entwined in vicious circle, researchers say

Typically viewed as unrelated problems, global warming and plastic pollution are instead inextricably trapped in a "vicious circle" where one feeds the other, researchers  report in Nature Communications. The mutually-reinforcing relationship escalates global warming, the degradation of materials, plastic waste and the leaching of toxic chemicals into the biosphere.

Plastics that we rely on every day will deteriorate more rapidly because of rising global temperatures, and one effect will be a demand for more plastics. Meeting that demand will further compound greenhouse emissions that drive up the global temperature. A self-reinforcing cycle is formed, creating a vicious circle between climate change and plastic pollution.

In 2019, plastics generated 3.4% of global greenhouse gas emissions, or about 1.8 billion tons, mostly on account of their production and conversion from fossil fuels, according to the Organization for Economic Co-operation and Development (OECD). By 2060 that amount is expected to more than double.

The researchers describe a feedback loop linking these emissions with heat, moisture and the weakening structural bonds that lend a wide range of advantageous properties to polymers, the term for materials—like plastic and rubber—that are formed from long chains of large molecules.

The higher the increase in temperature, the more the materials' properties are compromised. The stiffness of commonly used plastics like polyethylene, polypropylene and polyvinyl chloride decreases by more than 20% as temperatures climb between 23°C and 40°C.

This deterioration means more frequent replacement of polymer products—everything from clothing to auto parts and appliances—and consequently greater manufacturing volumes and rates.

Knock-on effects range from rendering food packaging unreliable to the fouling of waterways and fish habitats by an increase in microplastics, he says.

The report also documents the release of volatile organic compounds (VOCs) in a warming climate as well as other hazardous compounds including lubricants, flame retardants, plasticizers, antioxidants, colorants and UV/heat stabilizers. Heat will accelerate diffusion, evaporation and leaching of these substances into the air, soil, and water, the report says.

The researchers draw attention to the combined effects of heat and moisture, which rise together due to global warming. A warmer atmosphere increases the evaporation of moisture and can also hold more water vapour.

Part 1

Comment by Dr. Krishna Kumari Challa on March 20, 2024 at 9:30am

Rank Country Global biodiversity index Global rank
1. Democratic Republic of Congo 214.43 16th
2. Tanzania 213.10 17th
3. South Africa 207.94 19th
4. Kenya 179.72 23rd
5. Cameroon 172.41 24th
6. Madagascar 162.29 26th
7. Angola 160.67 27th
8. Guinea 153.43 30th
9. Mozambique 144.30 31st
10. Uganda 136.65 33rd

Comment by Dr. Krishna Kumari Challa on March 20, 2024 at 9:21am

In the case of mitochondrial recycling, this works as follows: If sufficient energy is available, a signal is transmitted from the insulin receptor on the cell surface to the mitochondria. Here, PINK1 blueprints are stored as mRNA molecules. When the insulin signal arrives, the blueprints are released by the mitochondria and the cell can produce additional PINK1 protein. This ensures that defective mitochondria are efficiently eliminated. In case of an energy shortage, or if the insulin receptor signal is missing, the blueprints for PINK1 remain tightly bound to the mitochondria.

On the one hand, the tight binding to mitochondria allows the PINK1 blueprints to hitchhike far into the nerve cells' long extensions. On the other hand, it reduces the availability of mRNA molecules for PINK1 production. PINK1 protein levels remain low and mitochondrial recycling is reduced—even though this can lead to the continued operation of damaged power plants.

Interrupted signaling with implications for health and aging

A similar situation can occur when the transmission of signals from the insulin receptor to mitochondria is disturbed due to disease. Defective insulin signaling is a hallmark of diabetes and has also been observed in the brain in connection with Alzheimer's disease.

It is also known that inefficient mitochondrial quality control can contribute to various neurodegenerative diseases.

Insulin signaling regulates Pink1 mRNA localization via modulation of AMPK activity to support PINK1 function in neurons, Nature Metabolism (2024). DOI: 10.1038/s42255-024-01007-w

Part 2

Comment by Dr. Krishna Kumari Challa on March 20, 2024 at 9:19am

In nerve cells, insulin regulates whether mitochondria are shut down or kept running

The hormone insulin controls many cellular processes and adapts them to the body's current energy supply. One of the insulin-regulated processes is the quality control of mitochondria in neurons, scientists have discovered.

When sufficient energy is available in the body, insulin facilitates the elimination of defective mitochondria. When energy is scarce or when the insulin signal is interrupted, mitochondrial recycling is reduced and cells continue to use their old power plants, even potentially damaged ones. The continued operation of faulty mitochondria could affect aging processes and neurological diseases.

Nerve cells place special demands on their energy supply. Due to their extensive branching and their high energy needs, they keep a close watch on their cellular power plants, the mitochondria. The cells have to ensure that there are always sufficient mitochondria available in their long extensions, the axons, where the power plants fuel the cell's communication with its neighboring cells. This is why neurons transport mitochondria even to the cells' most remote locations.

 Earlier research had shown that mitochondria carry along the blueprints of the PINK1 protein on their journey through the neuron.

PINK1 is a key protein that acts when mitochondria need to be removed because they are no longer functioning correctly. 

It can mark mitochondria for recycling and is precisely controlled by the cells." A failure to keep PINK1 in check could lead to a shortage of mitochondria, whereas the continued operation of defective cellular power plants can damage a cell.

Researchers have now uncovered that the hormone insulin is involved in mitochondrial quality control in neurons. Insulin is well-known for its role in regulating a cell's sugar uptake. It also controls many processes inside cells to precisely adjust them to the body's current energy supply.

Part 1

Comment by Dr. Krishna Kumari Challa on March 19, 2024 at 11:50am

Infantile amnesia

People   assume babies’ brains are simply not mature enough to form lasting memories. This is called infantile amnesia.

But scientists found that infantile amnesia seems to affect only certain kinds of memories, particularly the ones known as contextual memories, which involve connecting cues such as the layout of an environment with events that happen there. In humans, the forgotten memories include episodic memories: conscious recollections of where and when a specific event occurred.

 In contrast, young brains can recall other types of memories just fine, including semantic memories of the meanings of words and motor memories of skills such as how to draw a circle. 

Exactly when can the developing brain switch on the ability to form accessible long-term memories?

Data indicates it’s at about 20 months. Children that age who learned to associate a toy with a certain location in each room can remember the information for up to 6 months, whereas younger children only remember it for about 1 month.

The brain actually can create memories before age 3—although perhaps in a different way from adult memories—and those memories may persist into adulthood. But we can’t consciously access them.

Psychologists have found some evidence that early memories may linger, even if we can’t consciously access them.

The human and rodent studies both suggest infantile memories are not gone, only forgotten.

This forgetting probably serves some evolutionary purpose, whether that’s helping young brains learn how to attach the proper importance to events or developing a framework for the memory systems they will use throughout life.

Comment by Dr. Krishna Kumari Challa on March 19, 2024 at 7:25am

The researchers also found that people differed from each other in terms of how much glucose fluctuations impacted their cognitive speed, and some people—including older adults and adults with certain health conditions—were much more impacted by glucose fluctuations than others.

These results demonstrate that people can differ a lot from one another in how their brains are impacted by glucose.

This work  found that minimizing glucose fluctuations in daily life is important for optimizing processing speed, and this is especially true for people who are older or have other diabetes-related health conditions.

One surprise discovery was that participants' peak cognitive performance coincided with glucose levels that were slightly above their normal range, though performance dropped off as glucose levels rose even further.

 Dynamic associations between glucose and ecological momentary cognition in Type 1 Diabetes, npj Digital Medicine (2024). DOI: 10.1038/s41746-024-01036-5 , www.nature.com/articles/s41746-024-01036-5

Part 2

Comment by Dr. Krishna Kumari Challa on March 19, 2024 at 7:23am

Study shows glucose levels affect cognitive performance in people with type 1 diabetes differently

A new study  used advances in digital testing to demonstrate that naturally occurring glucose fluctuations impact cognitive function in people with type 1 diabetes (T1D).

Results of the study, published in npj Digital Medicine, show that cognition was slower in moments when glucose was atypical—that is, considerably higher or lower than someone's usual glucose level. However, some people were more susceptible to the cognitive effects of large glucose fluctuations than others.

In trying to understand how diabetes impacts the brain, this research shows that it is important to consider not only how people are similar, but also how they differ.

T1D is an autoimmune disease characterized by glucose variability. Previous laboratory studies have shown that very low and very high glucose levels impair cognitive function. However, technological limitations made it difficult to study the impact of naturally occurring glucose fluctuations on cognition outside of the laboratory, preventing researchers from obtaining repeated, high-frequency measurements within the same individuals over time. High-frequency measurements are necessary to understand whether glucose fluctuations impact cognition similarly for everyone.

In the new study, researchers used digital glucose sensors and smartphone-based cognitive tests to collect repeated, high-frequency glucose and cognitive data in 200 individuals with T1D. Glucose data were collected every five minutes and cognitive data were collected three times per day for fifteen days.

Collecting glucose and cognitive data unobtrusively, as participants went about their daily lives, allowed researchers to examine the cognitive impact of naturally occurring glucose variability. With many data points from each individual, they were able to use machine learning to test whether the impact of glucose on cognition differed from person to person.

The study showed that cognitive function was impaired when glucose was considerably higher or lower than usual, and this effect was observed for processing speed but not sustained attention. It is possible that processing speed is impacted by short-term, moment-to-moment fluctuations in glucose, whereas sustained attention is impacted by high or low glucose that persists over longer periods of time.

Part 1

Comment by Dr. Krishna Kumari Challa on March 19, 2024 at 7:11am

Two artificial intelligences talk to each other

Performing a new task based solely on verbal or written instructions, and then describing it to others so that they can reproduce it, is a cornerstone of human communication that still resists artificial intelligence (AI).

A team from the University of Geneva (UNIGE) has succeeded in modeling an artificial neural network capable of this cognitive prowess. After learning and performing a series of basic tasks, this AI was able to provide a linguistic description of them to a "sister" AI, which in turn performed them. These promising results, especially for robotics, are  published in Nature Neuroscience.

Performing a new task without prior training, on the sole basis of verbal or written instructions, is a unique human ability. What's more, once we have learned the task, we are able to describe it so that another person can reproduce it. This dual capacity distinguishes us from other species which, to learn a new task, need numerous trials accompanied by positive or negative reinforcement signals, without being able to communicate it to their congeners.

A sub-field of artificial intelligence (AI)—Natural language processing—seeks to recreate this human faculty, with machines that understand and respond to vocal or textual data. This technique is based on artificial neural networks, inspired by our biological neurons and by the way they transmit electrical signals to one another in the brain. However, the neural calculations that would make it possible to achieve the cognitive feat described above are still poorly understood.

Currently, conversational agents using AI are capable of integrating linguistic information to produce text or an image. But, according to researchers, they are not yet capable of translating a verbal or written instruction into a sensorimotor action, and even less explaining it to another artificial intelligence so that it can reproduce it.

The researchers have now succeeded in developing an artificial neuronal model with this dual capacity, albeit with prior training.

This model opens new horizons for understanding the interaction between language and behaviour. It is particularly promising for the robotics sector, where the development of technologies that enable machines to talk to each other.

 Reidar Riveland et al, Natural language instructions induce compositional generalization in networks of neurons, Nature Neuroscience (2024). DOI: 10.1038/s41593-024-01607-5

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