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Comment by Dr. Krishna Kumari Challa on August 25, 2020 at 7:26am

**Using a smartphone and audio software to pick a physical lock

A trio of researchers has found a way to pick an ordinary physical lock using a smartphone with special software

With traditional locks, such as those found on the front doors of most homes, a person inserts the proper (metal) key and then turns it. Doing so pushes up a series of pins in the lock by a certain amount based on the ridges on the key. When the pins are pushed in a way that matches a preset condition, the tumbler can turn, retracting the metal piece of the door assembly from its berth, allowing the door to open. In this new effort, the researchers have found that it is possible to record the sounds made as the key comes into contact with the pins and then as the pins move upward, and use software to recreate the conditions that produce the same noises. Those conditions can be used to fabricate a metal key to unlock the door. The result is a system the team calls SpiKey, which involves use of a smartphone to record lock clicks, decipher them and then create a key signature for use in creating a new metal key.

Soundarya Ramesh et al. Listen to Your Key, Proceedings of the 21st International Workshop on Mobile Computing Systems and Applications (2020). DOI: 10.1145/3376897.3377853 . PDF.

https://techxplore.com/news/2020-08-smartphone-audio-software-physi...

Comment by Dr. Krishna Kumari Challa on August 25, 2020 at 7:22am

Locust swarm could improve collision avoidance

Plagues of locusts, containing millions of insects, fly across the sky to attack crops, but the individual insects do not collide with each other within these massive swarms. Now a team of engineers is creating a low-power collision detector that mimics the locust avoidance response and could help robots, drones and even self-driving cars avoid collisions.

Mechanism of locusts: Locusts are unusual because they use a single, specialized neuron, called the Lobula Giant Movement Detector (LGMD), to avoid collisions.

The neuron receives two different signals. An image of an approaching locust falls on the avoiding locust's eye. The closer the invading locust gets, the larger the image and the stronger this excitation signal becomes. The other input is the change in angular velocity of the invading locust with respect to the avoiding locust.

Because the neuron has two branches, the locust computes the changes in these two inputs and realizes that something is going to collide.  So the avoiding locust changes direction.

The researchers developed a compact, nanoscale collision detector using monolayer molybdenum sulfide as a photodetector. They placed the photo detector on top of a programmable floating gate memory architecture that can mimic the locust's  neuron response using only a tiny amount of energy.

A low-power biomimetic collision detector based on an in-memory molybdenum disulfide photodetector, Nature Electronics (2020). DOI: 10.1038/s41928-020-00466-9 , www.nature.com/articles/s41928-020-00466-9

https://techxplore.com/news/2020-08-locust-swarm-collision.html?utm...

Comment by Dr. Krishna Kumari Challa on August 25, 2020 at 7:17am

**Study suggests hot nights pose greater threat to public health th...

Hong Kong has been experiencing hotter summers and more scorcher days in recent years due to climate change and heat island effect. Amid the increasing number of "hot nights," it is found that consecutive "hot nights" are more detrimental to human health than "very hot days," although the actual temperature does not reach the level of daytime, according to a collaborative research conducted by the Institute of Future Cities at The Chinese University of Hong Kong (CUHK), as well as researchers from the University of Hong Kong. The research also identified that lack of urban greenery and poor air ventilation in a high-density context are factors that lead to more "hot nights" than "hot days" in some areas. The team suggests that better urban planning and building design are long-term mitigation measures.

 Amid the increasing number of "hot nights," it is found that consecutive "hot nights" are more detrimental to human health than "very hot days," although the actual temperature does not reach the level of daytime, according to a collaborative research . The research also identified that lack of urban greenery and poor air ventilation in a high-density context are factors that lead to more "hot nights" than "hot days" in some areas. 

Apparently consecutive "hot nights" brought more health problems compared with "very hot days," especially for five or more consecutive "hot nights." It was also found that when consecutive "very hot days" were joined with consecutive "hot nights," such as two consecutive "very hot days" with three "hot nights," the health impact was significantly amplified, compared with only consecutive "very hot days." Moreover, females and older adults were determined to be relatively more vulnerable to extreme hot weather.

https://phys.org/news/2020-08-hot-nights-pose-greater-threat.html?u...

Restricting sleep may affect emotional reactions

Comment by Dr. Krishna Kumari Challa on August 25, 2020 at 7:12am

Ocean hitchhiker's sucker mechanism offers potential for underwater adhesion

A new study has revealed how remora suckerfish detach themselves from the surfaces they've clung to—and how the mechanism could provide inspiration for future reversible underwater adhesion devices.

Marine organisms mainly use two methods of adhesion in submerged environments: chemical adhesion and suction adhesion. Remora's hitchhiking behaviour uses suction adhesion and requires these fishes to be capable of both attaching and detaching regularly, but their detachment remains poorly understood.

Understanding detachment is essential in studying biological adhesive systems. It is also becoming increasingly important in many engineering applications such as surface peeling (surface painting, coating and transfer printing). Researchers  explored how a remora detaches to expand the understanding of this biological system, and to see how it could be applied to artificial adhesion mechanisms.

Siqi Wang et al. Detachment of the remora suckerfish disc: kinematics and a bio-inspired robotic model, Bioinspiration & Biomimetics (2020). DOI: 10.1088/1748-3190/ab9418

https://phys.org/news/2020-08-ocean-hitchhiker-sucker-mechanism-pot...

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Comment by Dr. Krishna Kumari Challa on August 25, 2020 at 6:37am

Adapting ideas from quantum physics to calculate alternative interventions for infection and cancer

Findings from a new study show for the first time how ideas from quantum physics can help develop novel drug interventions for bacterial infections and cancer.

demonstrated that principles of quantum control, a field of quantum physics used in computing applications, can be translated and applied to biological problems. They constructed a mathematical algorithm  that can be used to design and speed-up specific interventions to prevent or overturn drug resistance.

Typically cells in the presence of drugs evolve according to Darwinian natural selection: mutants that are resistant to the drug can outcompete their susceptible neighbors, dominating the population. Counterintuitively, one can also co-opt this process to achieve the opposite result, ultimately defeating drug resistance. For example, a mutation that causes resistance to one drug may cause extreme susceptibility to another, a phenomenon known as collateral sensitivity.

"If that mutant is initially only a small fraction of the population, we can use the first drug to encourage its dominance, and then apply the second drug to rapidly wipe out the infection

we also know that the first stage can be slow: mutations occur at random times, and waiting long enough until the mutant fully takes over could compromise treatment effectiveness and patient outcomes. The time it takes to ensure these interventions are successful has been a significant limitation to adopting evolutionary medicine into clinical practice.

Speeding up this process is where quantum physics can provide inspiration. "The randomness of mutations in evolution has intriguing mathematical parallels to the randomness of quantum phenomena,

This randomness makes it challenging to reliably and quickly drive a quantum system from one state to another. Solving this driving problem is an essential ingredient in certain kinds of quantum computing. Our new study exploits these parallels, translating a particular quantum technique known as counterdiabatic driving into the language of evolutionary biology

The researchers created a mathematical algorithm to calculate this intervention in evolutionary medicine applications. The algorithm's output is a prescription for dynamically altering the drug dosages or types to stay on the target path. The team demonstrated their technique by using it to manipulate evolution in simulations of living cells. These simulations were based on experimental data from an earlier study on a set of mutants showing varying degrees of resistance to anti-malarial drugs.

Controlling the speed and trajectory of evolution with counterdiabatic driving, Nature Physics (2020). DOI: 10.1038/s41567-020-0989-3 , www.nature.com/articles/s41567-020-0989-3

https://phys.org/news/2020-08-ideas-quantum-physics-alternative-int...

Comment by Dr. Krishna Kumari Challa on August 25, 2020 at 6:31am

Application of two engineering nanomaterials provides novel way to improve salt tolerance in plants

In a study published in Environmental Science: Nano, researchers showed the promoting effects of single-walled carbon nanohorns (SWCNHs) and ZnO nanoparticles (ZnO NPs) on plant growth and salt tolerance in Sophora alopecuroides seedlings. The researchers showed that changes in metabolomic profiling by SWCNHs and ZnO NPs contributed to salt tolerance in Sophora alopecuroides seedlings.

jinpeng wan et al. Comparative physiological and metabolomics analysis reveals that single-walled carbon nanohorns and ZnO nanoparticles affect salt tolerance in Sophora alopecuroides, Environmental Science: Nano (2020). DOI: 10.1039/D0EN00582G

https://phys.org/news/2020-08-application-nanomaterials-salt-tolera...

Comment by Dr. Krishna Kumari Challa on August 25, 2020 at 6:26am

Velcro method for more precise binding of drug particles

In order to deliver drug particles to the right place in the body—a field known as nanomedicine—selectivity plays an important role. After all, the drug only has to attach itself to the cells that need it. A theory from 2011 predicts that selectivity is not only based on the type of receptor, but also on the number and strength of the receptors on the cell. Researchers  are now proving this experimentally.

Cells interact with each other through receptors and ligands. They fit on each other like a key in a lock; a ligand of one cell only fits on the appropriate target receptor of the other cell. The field of nanomedicine makes use of this by imitating ligands that fit the receptors of the diseased cell that needs the drug.

The theory now proven  is based on this: In 2011, Daan Frenkel and his group in Cambridge used a theoretical model to predict that not only the type of ligands and receptors play a major role, but also the number and strength. This means that even weak ligands can bind, as long as there are enough receptors present on the surface of the target cell.

Compare it to Velcro. If one hook is fastened, the strip does not stick immediately. Only when several hooks are fastened does the bond become strong enough. This is also how it works in the human body; the weak binding of a ligand on a receptor becomes enormously strong the more there are.

And that's a useful feature for nanomedicine. Diseased cells do not always have different receptors than healthy cells, but they often have more receptors on their cell walls. By developing the drug in such a way that it only sticks to cells with a lot of receptors, you can still distinguish between diseased and healthy cells. This makes it possible to send the drug particles more precisely to the diseased cells in the body.

It 's now experimentally demonstrated with particles that many weak ligands give a high selectivity: The particles only bind if there are exactly enough receptors present. This creates a threshold value," explains van IJzendoorn. The researchers carried out a binding experiment for this purpose, designing particles with either receptor DNA or ligand DNA on its surface.

A magnetic field first pulled the particles toward each other, and after some time, released them. Van IJzendoorn: "This allowed us to optically measure how many particles had developed a strong molecular binding with each other."

By varying the number of DNA molecules and the strength of the ligand-receptor binding, not only were the researchers able to see how many bindings were needed for the particles to stay bonded, but also to observe the emergence of the  threshold value.

M. R. W. Scheepers el al., Multivalent weak interactions enhance selectivity of interparticle binding, PNAS (2020). www.pnas.org/cgi/doi/10.1073/pnas.2003968117

https://phys.org/news/2020-08-velcro-method-precise-drug-particles....

Comment by Dr. Krishna Kumari Challa on August 25, 2020 at 6:17am

COVID-19 pooling test method identifies asymptomatic carriers

A new COVID-19 pooling test  identifies all positive subjects, including asymptomatic carriers. P-BEST, an algorithmic method for pooling-based efficient SARS-CoV-2 testing, was developed by a group of researchers.

Approximately 10 to 30% of COVID-19-infected patients are asymptomatic and significant viral spread can occur days before symptom onset.

 This new single-stage diagnostic test will help prevent the spread of the disease by identifying these patients sooner and at a lower cost using significantly fewer tests."

https://medicalxpress.com/news/2020-08-covid-pooling-method-asympto...

Noam Shental et al. Efficient high-throughput SARS-CoV-2 testing to detect asymptomatic carriers, Science Advances (2020). DOI: 10.1126/sciadv.abc5961

Comment by Dr. Krishna Kumari Challa on August 25, 2020 at 6:10am

Autistic people's nerve cells differ before birth

Autism is a neurodevelopmental condition that researchers are now tracing back to prenatal development, even though the disorder is not diagnosed until at least 18 months of age. A new study now shows in human brain cells that the atypical development starts at the very earliest stages of brain organization, at the level of individual brain cells.

In a new study researchers used induced pluripotent stem cells, or iPSCs, to model early brain development. Their findings indicate that brain cells from autistic people develop differently to those from typical individuals.

The researchers isolated hair samples from nine autistic people and six typical people. By treating the cells with an array of growth factors, the scientists were able to drive the hair cells to become nerve cells, or neurons—much like those found in either the cortex or the midbrain region. iPSCs retain the genetic identity of the person from which they came and the cells re-start their development as it would have happened in the womb, providing a window into that person's brain development.

At various stages, the authors examined the developing cells' appearance and sequenced their RNA, to see which genes the cells were expressing.

At day 9, developing neurons from typical people formed "neural rosettes," an intricate, dandelion-like shape indicative of typically developing neurons. Cells from autistic people formed smaller rosettes or did not form rosettes at all. And key developmental genes were expressed at lower levels in cells from autistic people.

At days 21 and 35, the cells from typical and autistic people differed significantly in a number of ways, suggesting that the makeup of neurons in the cortex differs in the autistic and typically developing brain.

Dwaipayan Adhya et al, Atypical Neurogenesis in Induced Pluripotent Stem Cells From Autistic Individuals, Biological Psychiatry (2020). DOI: 10.1016/j.biopsych.2020.06.014

https://medicalxpress.com/news/2020-08-autistic-people-nerve-cells-...

Comment by Dr. Krishna Kumari Challa on August 25, 2020 at 6:02am

Biologists discover a gene critical to the development of columbines' iconic spurs

Once in a while, over the history of life, a new trait evolves that leads to an explosion of diversity in a group of organisms. Take wings, for instance. Every group of animals that evolved them has spun off into a host of different species—birds, bats, insects and pterosaurs. Scientists call these "key innovations."

Understanding the development of key innovations is critical to understanding the evolution of the amazing array of organisms on Earth. Most of these happened deep in the distant past, making them difficult to study from a genetic perspective. Fortunately, one group of plants has acquired just such a trait in the past few million years.

Columbines, with their elegant nectar spurs, promise scientists an opportunity to investigate the genetic changes that underpin a key innovation. 

After much research scientists have identified a gene critical to the development of these structures. And to their knowledge, this is among the first key innovations for which a critical developmental gene has been identified and named POPOVICH. 

 Evangeline S. Ballerini el al., "POPOVICH, encoding a C2H2 zinc-finger transcription factor, plays a central role in the development of a key innovation, floral nectar spurs, in Aquilegia," PNAS (2020). www.pnas.org/cgi/doi/10.1073/pnas.2006912117

https://phys.org/news/2020-08-biologists-gene-critical-columbines-i...

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