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Ahmedabad fights Covid: Except milk parlours, chemists, all shops to remain shut




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Scarlet fever

Passions ran high at this party which had the evergreen favourite theme of Red and Black.




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'Distribute grants to cow shelters at earliest', orders CM Gehlot

'Distribute grants to cow shelters at earliest', orders CM Gehlot




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Bhopal: 396 people recover from COVID-19 with early oxygen therapy




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Early return of J and K students from Bangladesh urged




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Carlyle Group to invest up to ₹1,800 cr. to acquire majority stake in SeQuent Scientific

Carlyle Group and existing promoters of animal healthcare company SeQuent Scientific Ltd. have announced that CA Harbor Investments, an affiliated ent




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A phenol phosphorescent microsensor of mesoporous molecularly imprinted polymers

RSC Adv., 2020, 10,17906-17913
DOI: 10.1039/D0RA02834G, Paper
Open Access
Xiaodong Lv, Peng Gao
Based on the optical quenching phenomenon, a smart mesoporous phosphorescent microsensor was built.
The content of this RSS Feed (c) The Royal Society of Chemistry




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In 60 days, Maharashtra Covid-19 cases zoom from 2 to nearly 20K!




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Govt extends early bird scheme to commercial establishments | Hyderabad News - Times of India

Govt extends early bird scheme to commercial establishments | Hyderabad News - Times of India




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Punjab Police distribute nearly 1.9 lakh food packets across state




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'I'm a fearless actor now'

'Having lived through cancer, through so many ups and downs, I'm not particularly attached to attention or success -- it's lovely if it's there, it's fine if it's not.'




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Performance of nearly fixed offset asymmetric channel-cut crystals for X-ray monochromators

X-ray double-crystal monochromators face a shift of the exit beam when the Bragg angle and thus the transmitted photon energy changes. This can be compensated for by moving one or both crystals accordingly. In the case of monolithic channel-cut crystals, which exhibit utmost stability, the shift of the monochromated beam is inevitable. Here we report performance tests of novel, asymmetrically cut, channel-cut crystals which reduce the beam movements by more than a factor of 20 relative to the symmetric case over the typical energy range of an EXAFS spectrum at the Cu K-edge. In addition, the presented formulas for the beam offset including the asymmetry angle directly indicate the importance of this value, which has been commonly neglected so far in the operation of double-crystal monochromators.





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X-ray photon correlation spectroscopy of protein dynamics at nearly diffraction-limited storage rings

This study explores the possibility of measuring the dynamics of proteins in solution using X-ray photon correlation spectroscopy (XPCS) at nearly diffraction-limited storage rings (DLSRs). We calculate the signal-to-noise ratio (SNR) of XPCS experiments from a concentrated lysozyme solution at the length scale of the hydrodynamic radius of the protein molecule. We take into account limitations given by the critical X-ray dose and find expressions for the SNR as a function of beam size, sample-to-detector distance and photon energy. Specifically, we show that the combined increase in coherent flux and coherence lengths at the DLSR PETRA IV yields an increase in SNR of more than one order of magnitude. The resulting SNR values indicate that XPCS experiments of biological macromolecules on nanometre length scales will become feasible with the advent of a new generation of synchrotron sources. Our findings provide valuable input for the design and construction of future XPCS beamlines at DLSRs.




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The early history of cryo-cooling for macromolecular crystallography

This paper recounts the first successful cryo-cooling of protein crystals that demonstrated the reduction in X-ray damage to macromolecular crystals. The project was suggested by David C. Phillips in 1965 at the Royal Institution of Great Britain and continued in 1967 at the Weizmann Institute of Science, where the first cryo-cooling experiments were performed on lysozyme crystals, and was completed in 1969 at Purdue University on lactate dehydrogenase crystals. A 1970 publication in Acta Crystallographica described the cryo-procedures, the use of cryo-protectants to prevent ice formation, the importance of fast, isotropic cryo-cooling and the collection of analytical data showing more than a tenfold decrease in radiation damage in cryo-cooled lactate dehydrogenase crystals. This was the first demonstration of any method that reduced radiation damage in protein crystals, which provided crystallographers with suitable means to employ synchrotron X-ray sources for protein-crystal analysis. Today, fifty years later, more than 90% of the crystal structures deposited in the Protein Data Bank have been cryo-cooled.




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Linearly polarized X-ray fluorescence computed tomography based on a Thomson scattering light source: a Monte Carlo study

A Thomson scattering X-ray source can provide quasi-monochromatic, continuously energy-tunable, polarization-controllable and high-brightness X-rays, which makes it an excellent tool for X-ray fluorescence computed tomography (XFCT). In this paper, we examined the suppression of Compton scattering background in XFCT using the linearly polarized X-rays and the implementation feasibility of linearly polarized XFCT based on this type of light source, concerning the influence of phantom attenuation and the sampling strategy, its advantage over K-edge subtraction computed tomography (CT), the imaging time, and the potential pulse pile-up effect by Monte Carlo simulations. A fan beam and pinhole collimator geometry were adopted in the simulation and the phantom was a polymethyl methacrylate cylinder inside which were gadolinium (Gd)-loaded water solutions with Gd concentrations ranging from 0.2 to 4.0 wt%. Compared with the case of vertical polarization, Compton scattering was suppressed by about 1.6 times using horizontal polarization. An accurate image of the Gd-containing phantom was successfully reconstructed with both spatial and quantitative identification, and good linearity between the reconstructed value and the Gd concentration was verified. When the attenuation effect cannot be neglected, one full cycle (360°) sampling and the attenuation correction became necessary. Compared with the results of K-edge subtraction CT, the contrast-to-noise ratio values of XFCT were improved by 2.03 and 1.04 times at low Gd concentrations of 0.2 and 0.5 wt%, respectively. When the flux of a Thomson scattering light source reaches 1013 photons s−1, it is possible to finish the data acquisition of XFCT at the minute or second level without introducing pulse pile-up effects.




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Monte Carlo simulation of neutron scattering by a textured polycrystal

A method of simulating the neutron scattering by a textured polycrystal is presented. It is based on an expansion of the scattering cross sections in terms of the spherical harmonics of the incident and scattering directions, which is derived from the generalized Fourier expansion of the polycrystal orientation distribution function. The method has been implemented in a Monte Carlo code as a component of the McStas software package, and it has been validated by computing some pole figures of a Zircaloy-4 plate and a Zr–2.5Nb pressure tube, and by simulating an ideal transmission experiment. The code can be used to estimate the background generated by components of neutron instruments such as pressure cells, whose walls are made of alloys with significant crystallographic texture. As a first application, the effect of texture on the signal-to-noise ratio was studied in a simple model of a diffraction experiment, in which a sample is placed inside a pressure cell made of a zirconium alloy. With this setting, the results of two simulations were compared: one in which the pressure-cell wall has a uniform distribution of grain orientations, and another in which the pressure cell has the texture of a Zr–2.5Nb pressure tube. The results showed that the effect of the texture of the pressure cell on the noise of a diffractogram is very important. Thus, the signal-to-noise ratio can be controlled by appropriate choice of the texture of the pressure-cell walls.




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Skeletal casts of early hominin ancestor from Africa donated to National Museum of Natural History

A. sediba was discovered in 2008 in the Malapa Cave at the Cradle of Humankind World Heritage Site located outside Johannesburg.

The post Skeletal casts of early hominin ancestor from Africa donated to National Museum of Natural History appeared first on Smithsonian Insider.




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New archaeological evidence reveals California’s Channel Islands as North America’s earliest seafaring economy

Evidence for a diversified sea-based economy among North American inhabitants dating from 12,200 to 11,400 years ago is emerging from three sites on California's Channel Islands.

The post New archaeological evidence reveals California’s Channel Islands as North America’s earliest seafaring economy appeared first on Smithsonian Insider.




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Artist’s recreation of 7- to 6-million-year-old early human unveiled in Hall of Human Origins

Meet Sahelanthropus tchadensis. This newly unveiled bust by artist John Gurche is now on view in the the Hall of Human Origins at the Smithsonian's National Museum of Natural History.

The post Artist’s recreation of 7- to 6-million-year-old early human unveiled in Hall of Human Origins appeared first on Smithsonian Insider.




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Facebook friends help scientists quickly identify nearly 5,000 fish specimens collected in Guyana

Faced with insufficient time and inadequate library resources to tackle the problem on their own, they instead posted a catalog of specimen images to Facebook and turned to their network of colleagues for help.

The post Facebook friends help scientists quickly identify nearly 5,000 fish specimens collected in Guyana appeared first on Smithsonian Insider.




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Charles Doolittle Walcott (1850-1927) family campsite in the Canadian Rockies

Collecting trips for Charles Doolittle Walcott (1850-1927), paleontologist and fourth Secretary of the Smithsonian Institution, were often a family affair. This 1910 photograph shows their […]

The post Charles Doolittle Walcott (1850-1927) family campsite in the Canadian Rockies appeared first on Smithsonian Insider.



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Chandra X-Ray Observatory finds massive black holes common in early universe

Using the deepest X-ray image ever taken, astronomers found the first direct evidence that massive black holes were common in the early universe. This discovery from NASA's Chandra X-ray Observatory shows that very young black holes grew more aggressively than previously thought, in tandem with the growth of their host galaxies.

The post Chandra X-Ray Observatory finds massive black holes common in early universe appeared first on Smithsonian Insider.




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Wayne Clough & Carlos Jaramillo, at a research site near the Panama Canal.

Smithsonian Secretary Wayne Clough, left, talks with Carlos Jaramillo, scientist at the Smithsonian Tropical Research Institute in Panama, at a research site near the Panama […]

The post Wayne Clough & Carlos Jaramillo, at a research site near the Panama Canal. appeared first on Smithsonian Insider.




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Evolution of earliest horses driven by climate change

Paleontologists studying an extreme short-term global warming event have discovered direct evidence about how mammals respond to rising temperatures. In a study that appeared recently […]

The post Evolution of earliest horses driven by climate change appeared first on Smithsonian Insider.





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Alien Earths may have formed in Universe earlier than expected

New research by a team of astronomers found that planets smaller than Neptune are located around a wide variety of stars, including those with fewer heavy elements than the Sun.

The post Alien Earths may have formed in Universe earlier than expected appeared first on Smithsonian Insider.




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Report paints a new picture of early human impact on the Amazon River Basin

The newly reported reconstruction of Amazonian prehistory by a Smithsonian scientist, Dolores R. Piperno, and her colleagues suggests that large areas of western Amazonia were sparsely inhabited.

The post Report paints a new picture of early human impact on the Amazon River Basin appeared first on Smithsonian Insider.




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Discovery: Turtle shells appeared 40 million years earlier than previously believed

Unique among Earth’s creatures, turtles are the only animals to form a shell on the outside of their bodies through a fusion of modified ribs, […]

The post Discovery: Turtle shells appeared 40 million years earlier than previously believed appeared first on Smithsonian Insider.




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Webcast w/ bird detective, Carla Dove

Carla Dove is an Ornithologist at the Smithsonian National Museum of Natural History. In this Feb. 12 Webcast join her in analyzing the remains of […]

The post Webcast w/ bird detective, Carla Dove appeared first on Smithsonian Insider.




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“Early Women in Science” Profiles Trailblazing Women

“Early Women in Science” is an online exhibition of 16 women scientists who began their work before 1922. A Biodiversity Heritage Library exhibition, it profiles forward-thinking […]

The post “Early Women in Science” Profiles Trailblazing Women appeared first on Smithsonian Insider.





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Smithsonian Scientists Trace Anthropocene Roots to Early Human Activity

A new analysis of the fossil record by scientists at the Smithsonian’s National Museum of Natural History has revealed that the structure of plant and […]

The post Smithsonian Scientists Trace Anthropocene Roots to Early Human Activity appeared first on Smithsonian Insider.




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Early indicator of cheetah pregnancy identified

A new study from the Smithsonian Conservation Biology Institute (SCBI) is helping make headway in an area of animal management that has historically proven challenging: […]

The post Early indicator of cheetah pregnancy identified appeared first on Smithsonian Insider.




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Study of bacteria inside guts of wild Canada geese shows greater danger than earlier studies exposed

In the early 20th century, Canada geese were considered endangered in the U.S. So in the 1950s and 1960s, birds from the Midwest were released […]

The post Study of bacteria inside guts of wild Canada geese shows greater danger than earlier studies exposed appeared first on Smithsonian Insider.




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With 1844 first edition, Smithsonian Libraries completes its collection of Charles Darwin’s three-volume geology series

Smithsonian Institution Libraries has recently acquired a rare first edition of Darwin's Geological Observations on the Volcanic Islands, Visited During the Voyage of the H.M.S. Beagle.

The post With 1844 first edition, Smithsonian Libraries completes its collection of Charles Darwin’s three-volume geology series appeared first on Smithsonian Insider.




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Sun-like Star Shows Magnetic Field Critical for Life on the early Earth

Nearly four billion years ago, life arose on Earth. Life appeared because our planet had a rocky surface, liquid water, and a blanketing atmosphere. But […]

The post Sun-like Star Shows Magnetic Field Critical for Life on the early Earth appeared first on Smithsonian Insider.




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Diamonds are a planet’s best friend? In the early universe, perhaps

Could the universe’s earliest stars have formed planets, and if so, what might they have looked like? That was the question Harvard-Smithsonian Center for Astrophysics […]

The post Diamonds are a planet’s best friend? In the early universe, perhaps appeared first on Smithsonian Insider.




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After a nearly 20-year search, this Jamaican bird is probably extinct

The Jamaican golden swallow was last seen in 1982. From 1994 to 2012, Smithsonian ornithologist Gary Graves combed the island of Jamaica to document several […]

The post After a nearly 20-year search, this Jamaican bird is probably extinct appeared first on Smithsonian Insider.




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Meet Our Scientist: Forensic ornithologist Carla Dove explains bird-strike science

When birds and planes collide: Carla Dove, a forensic ornithologist at the Smithsonian's National Museum of Natural History, talks about the work of the Smithsonian's Feather Identification Lab and its role in improving aviation safety.

The post Meet Our Scientist: Forensic ornithologist Carla Dove explains bird-strike science appeared first on Smithsonian Insider.



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Firefox. Earlier version for 32 bit os?




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Study shows parasites may be among earliest victims of climate change

The Earth’s changing climate could cause the extinction of up to a third of its parasite species by 2070, according to a global analysis reported […]

The post Study shows parasites may be among earliest victims of climate change appeared first on Smithsonian Insider.




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Maya more warlike than previously thought

Full Text:

The Maya of Central America are thought to have been a kinder, gentler civilization, especially compared to the Aztecs of Mexico. At the peak of Mayan culture some 1,500 years ago, warfare seemed ritualistic, designed to extort ransom for captive royalty or to subjugate rival dynasties, with limited impact on the surrounding population. Only later, archeologists thought, did increasing drought and climate change lead to total warfare -- cities and dynasties were wiped off the map in so-called termination events -- and the collapse of the lowland Maya civilization around 1,000 A.D. (or C.E., current era). New evidence unearthed by National Science Foundation-funded researchers call all this into question, suggesting that the Maya engaged in scorched-earth military campaigns -- a strategy that aims to destroy anything of use, including cropland -- even at the height of their civilization, a time of prosperity and artistic sophistication. The finding also indicates that this increase in warfare, possibly associated with climate change and resource scarcity, was not the cause of the disintegration of the lowland Maya civilization.

Image credit: Francisco Estrada-Belli/Tulane




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Early Intervention Is Key To Educating Children With Autism

The National Institutes of Health and the U.S. Department of Education should promote routine early screenings of children for autistic spectrum disorders, much like they are promoted for vision and hearing problems, says a new report from the National Research Council of the National Academies.




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High-Quality Education, Early Screening Are Key To Nurturing Minority Students With Special Needs or Talents

To ensure that minority students who are poorly prepared for school are not assigned to special education for that reason, educators should be required to first provide them with high-quality instruction and social support in a general education classroom before making a determination that special education is needed.




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U.S. Loses up to $130 Billion Annually as Result of Poor Health, Early Death Due to Lack of Insurance

The value of what the United States loses because of the poorer health and earlier death experienced by the 41 million Americans who lack health insurance is estimated to be $65 billion to $130 billion every year, according to a first-ever economic analysis of the costs of uninsurance for society overall.




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Preterm Births Cost U.S. $26 Billion a Year - Multidisciplinary Research Effort Needed to Prevent Early Births

The high rate of premature births in the United States constitutes a public health concern that costs society at least $26 billion a year, according to a new report from the Institute of Medicine of the National Academies.




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Biomarker Tests for Molecularly Targeted Therapies Need Better Evidence, Oversight

Potentially useful biomarker tests for molecularly targeted therapies are not being adopted appropriately into clinical practice because of a lack of common evidentiary standards necessary for regulatory, reimbursement, and treatment decisions, says a new report by the National Academies of Sciences, Engineering, and Medicine.




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Opening Remarks from Bruce Darling, Executive Officer, National Academy of Sciences and National Research Council Report Release Event for Preparing for Future Products of Biotechnology

Good morning. Welcome to the release of the report Preparing for Future Products of Biotechnology, from the National Academies of Sciences, Engineering, and Medicine.