Comment

Comment by Dr. Krishna Kumari Challa on July 31, 2020 at 4:44am

Cosmic tango between the very small and the very large

While Einstein's theory of general relativity can explain a large array of fascinating astrophysical and cosmological phenomena, some aspects of the properties of the universe at the largest-scales remain a mystery. A new study using loop quantum cosmology—a theory that uses quantum mechanics to extend gravitational physics beyond Einstein's theory of general relativity—accounts for two major mysteries. While the differences in the theories occur at the tiniest of scales—much smaller than even a proton—they have consequences at the largest of accessible scales in the universe. The study, which appears online July 29 in the journal Physical Review Letters, also provides new predictions about the universe that future satellite missions could test.

While a zoomed-out picture of the universe looks fairly uniform, it does have a large-scale structure, for example because galaxies and dark matter are not uniformly distributed throughout the universe. The origin of this structure has been traced back to the tiny inhomogeneities observed in the Cosmic Microwave Background (CMB)—radiation that was emitted when the universe was 380 thousand years young that we can still see today. But the CMB itself has three puzzling features that are considered anomalies because they are difficult to explain using known physics.

"While seeing one of these anomalies may not be that statistically remarkable, seeing two or more together suggests we live in an exceptional universe.

A recent study in the journal Nature Astronomy proposed an explanation for one of these anomalies that raised so many additional concerns, they flagged a 'possible crisis in cosmology.' Using quantum loop cosmology, however, we have resolved two of these anomalies naturally, avoiding that potential crisis."

Research over the last three decades has greatly improved our understanding of the early universe, including how the inhomogeneities in the CMB were produced in the first place. These inhomogeneities are a result of inevitable quantum fluctuations in the early universe. During a highly accelerated phase of expansion at very early times—known as inflation—these primordial, miniscule fluctuations were stretched under gravity's influence and seeded the observed inhomogeneities in the CMB.

Abhay Ashtekar et al, Alleviating the Tension in the Cosmic Microwave Background using Planck-Scale Physics, Physical Review Letters (2020). DOI: 10.1103/PhysRevLett.125.051302

https://phys.org/news/2020-07-cosmic-tango-small-large.html?utm_sou...

Comment by Dr. Krishna Kumari Challa on July 31, 2020 at 4:34am

Ancient mountain formation and monsoons helped create a modern biodiversity hotspot

https://phys.org/news/2020-07-ancient-mountain-formation-monsoons-m...

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Origami microbots: Centuries-old artform guides cutting-edge advances in tiny machines

https://techxplore.com/news/2020-07-origami-microbots-centuries-old...

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Fear conditioning: Transcranial stimulation to prevent fear memories from returning

A research group from the University of Bologna has succeeded in modifying the negative effect of a returning memory that triggers fear, and developed a new non-invasive experimental protocol. The result of this study, published in the journal Current Biology, is an innovative protocol that combines fear conditioning—a stimulus associated with something unpleasant that induces a negative memory—and the neurostimulation of a specific site of the prefrontal cortex.

This process alters the perception of an unpleasant (aversive) event so that it will no longer induce fear. "This experimental protocol combining transcranial stimulation and memory reconsolidation allowed us to modify an aversive memory that the participants had learned the day before," explains Sara Borgomaneri, a researcher at the University of Bologna and first author of the study. "This result has relevant repercussions for understanding how memory works. It might even lead to the development of new therapies to deal with traumatic memories."

Borgomaneri et al., State-dependent TMS over prefrontal cortex disrupts fear memory reconsolidation and prevents the return of fear. Current Biology, (2020).

https://medicalxpress.com/news/2020-07-transcranial-memories.html?u...

Comment by Dr. Krishna Kumari Challa on July 30, 2020 at 5:41am

‘Keystone’ Species Key To Rebuilding Gut Microbiota After Antibiotics The discovery of gut bacteria critical to restoring gut health offers new insights into microbiome recovery after antibiotic treatment.

https://www.asianscientist.com/2020/07/in-the-lab/keystone-gut-micr...

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Some Uninfected People Have T-Cell Immunity To COVID-19 Researchers were surprised to find memory T-cells in people with no history of SARS, COVID-19, or contact with SARS or COVID-19 patients.

https://www.asianscientist.com/2020/07/health/memory-t-cell-immunit...

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New Report Identifies The 'Greatest Risk' to Human Health, And It's Not a Virus. It is air pollution!

https://www.sciencealert.com/air-pollution-greatest-risk-to-global-...

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Scientists Start Assembling The World's Largest Nuclear Fusion Experiment It'll be 10 times hotter than the Sun.

https://www.sciencealert.com/scientists-start-assembling-the-world-...

Comment by Dr. Krishna Kumari Challa on July 30, 2020 at 5:20am

Meta-Research: International authorship and collaboration across bioRxiv preprints

Preprints are becoming well established in the life sciences, but relatively little is known about the demographics of the researchers who post preprints and those who do not, or about the collaborations between preprint authors. Here, based on an analysis of 67,885 preprints posted on bioRxiv, it was found that some countries, notably the United States and the United Kingdom, are overrepresented on bioRxiv relative to their overall scientific output, while other countries (including China, Russia, and Turkey) show lower levels of bioRxiv adoption. This research also describes a set of ‘contributor countries’ (including Uganda, Croatia and Thailand): researchers from these countries appear almost exclusively as non-senior authors on international collaborations. They also found multiple journals that publish a disproportionate number of preprints from some countries, a dynamic that almost always benefits manuscripts from the US.

https://elifesciences.org/articles/58496?utm_source=content_alert&a...

Comment by Dr. Krishna Kumari Challa on July 30, 2020 at 5:12am

Research team exactly solves experimental puzzle in high temperature superconductivity

https://phys.org/news/2020-07-team-experimental-puzzle-high-tempera...

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https://phys.org/news/2020-07-simulating-quantum-butterfly-effect-r...

Simulating quantum 'time travel' disproves butterfly effect in quantum realm

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Microbes revived after 100 million years

Scientists have managed to wake up microbes that have been buried deep beneath the sea floor — apparently in a dormant state — since dinosaurs walked on Earth

https://www.nature.com/articles/s41467-020-17330-1?utm_source=Natur...

Comment by Dr. Krishna Kumari Challa on July 30, 2020 at 5:08am

Gold nanosensor spots difference between dengue, Zika

A new class of nanosensor developed in Brazil could more accurately identify dengue and Zika infections, a task that is complicated by their genetic similarities and which can result in misdiagnosis. The technique uses gold nanoparticles and can "observe" viruses at the atomic level.

Dengue is a disease that kills—and can do so quickly if the right diagnosis is not made. As for Zika, it offers risks for fetuses to develop microcephaly, and we can't let pregnant women spend seven or eight months wondering whether they have the virus or not

Belonging to the Flavivirus genus in the Flaviviridae family, Zika and dengue viruses share more than 50 percent similarity in their amino acid sequence. Both viruses are spread by mosquitos and can have long-term side effects. The Flaviviridae virus family was named after the yellow fever virus and comes from the Latin word for golden, or yellow, in color.

Diagnosing dengue virus infections is a high priority in countries affected by annual epidemics of dengue fever. The correct diagnostic is essential for patient managing and prognostic as there are no specific antiviral drugs to treat the infection.

It is almost impossible to differentiate between dengue and Zika viruses.

A serologic test that detects antibodies against dengue also captures Zika-generated antibodies. Scientists call this 'cross-reactivity'. 

There is also no specific antiviral treatment for Zika and the search for a vaccine is ongoing.

Virus differentiation is important to accurately measure the real impact of both diseases on public health. The most widely used blood test, the enzyme-linked immunosorbent assay (ELISA), is limited in its ability to tell the difference between the viruses.

As dengue has four variations, known as serotypes, the team created four different nanoparticles and covered each of them with a different dengue protein. They applied ELISA serum and a blood sample. The researchers found that sample antibodies bound with the viruses' proteins, changing the pattern of electrons on the gold nanoparticle surface.

The researchers  could see this change by applying certain frequencies of light on the nanoparticle's surface. Dengue proteins absorbed light—Zika ones did not.

The study argues that the gold nanoparticle-based test is more precise than other blood antibody tests because of its high sensitivity and capacity to identify which virus has been detected. The fact that this test doesn't require reagents and uses ELISA equipment, which is widely available and low cost.

Alice F. Versiani et al. Nanosensors based on LSPR are able to serologically differentiate dengue from Zika infections, Scientific Reports (2020). DOI: 10.1038/s41598-020-68357-9

https://phys.org/news/2020-07-gold-nanosensor-difference-dengue-zik...

Comment by Dr. Krishna Kumari Challa on July 29, 2020 at 6:36am

The Brittle Star That Sees with Its Body

It turns out that eyes aren’t necessary for vision

https://www.scientificamerican.com/article/the-brittle-star-that-se...

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https://phys.org/news/2020-07-method-properties-complex-quantum.htm...

A method to predict the properties of complex quantum systems

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https://phys.org/news/2020-07-remnant-ancient-globular-cluster-kind...

Discovered: Remnant of ancient globular cluster that's 'the last of its kind'

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https://phys.org/news/2020-07-encode-consortium-rna-sequences-invol...

RNA sequences that are involved in regulating gene expression have been identified

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https://phys.org/news/2020-07-giant-atoms-enable-quantum.html?utm_s...

'Giant atoms' enable quantum processing and communication in one

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https://phys.org/news/2020-07-decline-bees-pollinators-threatens-cr...

Decline of bees, other pollinators threatens crop yields

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https://phys.org/news/2020-07-uncover-cells-interact-proteins-wound...

Researchers uncover how cells interact with supporting proteins to heal wounds

Comment by Dr. Krishna Kumari Challa on July 29, 2020 at 5:31am

Scientists reveal an explosive secret hidden beneath seemingly trustworthy volcanoes

An international team of volcanologists working on remote islands in the Galápagos Archipelago has found that volcanoes which reliably produce small basaltic lava eruptions hide chemically diverse magmas in their underground plumbing systems—including some with the potential to generate explosive activity.

https://phys.org/news/2020-07-scientists-reveal-explosive-secret-hi...

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Microbiologists clarify relationship between microbial diversity and soil carbon storage:

shifts in the diversity of soil microbial communities can change the soil's ability to sequester carbon, where it usually helps to regulate climate.

https://phys.org/news/2020-07-microbiologists-relationship-microbia...

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** https://phys.org/news/2020-07-pesticides-crops-hydrophobic-pollutan...

Pesticides can protect crops from hydrophobic pollutants

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** https://www.sciencenews.org/article/black-hole-circling-wormhole-we...

A black hole circling a wormhole would emit weird gravitational waves

Hypothetical tunnels in spacetime could show up in LIGO and Virgo data

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**Vaccine nationalism: Coronavirus: how countries aim to get the vaccine first by cutting opaque supply deals

https://theconversation.com/coronavirus-how-countries-aim-to-get-th...

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‘Vaccine nationalism’ threatens global plan to distribute COVID-19 shots fairly

https://www.sciencemag.org/news/2020/07/vaccine-nationalism-threate...

Comment by Dr. Krishna Kumari Challa on July 29, 2020 at 5:25am

Researchers have for the first time measured a fundamental property of magnets called magnon polarization—and in the process, are making progress towards building low-energy devices.

https://phys.org/news/2020-07-probing-properties-magnetic-quasi-par...

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CERN experiment reports first evidence for ultra-rare process that could lead to new physics

Scientists at CERN have reported on their first significant evidence for a process predicted by theory, paving the way for searches for evidence of new physics in particle processes that could explain dark matter and other mysteries of the universe.

the first significant experimental evidence for the ultra-rare decay of the charged kaon into a charged pion and two neutrinos, (i.e. K⁺ → π⁺νν).

The decay process is important in cutting-edge physics research because it is so sensitive to deviations from theoretical predictions. This means that it is one of the most interesting things to observe for physicists looking for evidence to supports alternative theoretical model in particle physics.

https://phys.org/news/2020-07-cern-evidence-ultra-rare-physics.html...

Comment by Dr. Krishna Kumari Challa on July 29, 2020 at 5:23am

Discovery will allow more sophisticated work at nanoscale

The movement of fluids through small capillaries and channels is crucial for processes ranging from blood flow through the brain to power generation and electronic cooling systems, but that movement often stops when the channel is smaller than 10 nanometers.

Researchers have reported a new understanding of the process and why some fluids stagnate in these tiny channels, as well as a new way to stimulate the fluid flow by using a small increase in temperature or voltage to promote mass and ion transport.

The work explores the movement of fluids with lower surface tension, which allows the bonds between molecules to break apart when forced into narrow channels, stopping the process of fluid transport, known as capillary wicking. 

This capillary force drives liquid flow in small channels and is the critical mechanism for mass transport in nature and technology—that is, in situations ranging from blood flow in the human brain to the movement of water and nutrients from soil to plant roots and leaves, as well as in industrial processes.

But differences in the surface tension of some fluids causes the wicking process—and therefore, the movement of the fluid—to stop when those channels are smaller than 10 nanometers. The researchers reported that it is possible to prompt continued flow by manipulating the surface tension through small stimuli, such as raising the temperature or using a small amount of voltage.

The temperature even slightly can activate movement by changing surface tension, which they dubbed "nanogates." Depending on the liquid, raising the temperature between 2 degrees Centigrade and 3 degrees C is enough to mobilize the fluid.The surface tension can be changed through different variables.

The simplest one is temperature. If you change temperature of the fluid, you can activate this fluid flow again." The process can be fine-tuned to move the fluid, or just specific ions within it, offering promise for more sophisticated work at nanoscale.

"The surface tension nanogates promise platforms to govern nanoscale functionality of a wide spectrum of systems, and applications can be foreseen in drug delivery, energy conversion, power generation, seawater desalination, and ionic separation.

Masoumeh Nazari et al. Surface Tension Nanogates for Controlled Ion Transport, ACS Applied Nano Materials (2020). DOI: 10.1021/acsanm.0c01304

https://phys.org/news/2020-07-discovery-sophisticated-nanoscale.htm...

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