Researchers have stumbled upon evidence of an unknown virus that may be responsible for the persistence of kala-azar or visceral leishmaniasis, a parasite infection that has spawned epidemics and sickened thousands of Indians for over a century. It's still early to pointedly blame the virus but its discovery portends a new kind of treatment regime and may aid attempts to eradicating the disease. Historically, the parasite Leishmania donovani is believed to be responsible for the dreaded infection. People get infected when bitten by an insect called the sandfly, which harbours the disease-causing parasite. Scientists from West Bengal and Uttar Pradesh said that another parasite may be involved. Another parasite called Leptomonas seymouri may also be present. The researchers inferred this after they found the L seymouri and a virus called Lepsey NLV1 within it in 20 of 22 biological samples of patients who had a residual L donovani infection. They reported their findings in an online version of the peer-reviewed Archives of Virology. Kala Azar: Know More Kala-azar is endemic to the Indian subcontinent in 119 districts in four countries (Bangladesh, Bhutan, India and Nepal). India itself accounts for half the global burden of the disease. If untreated, kala-azar can kill within two years of the onset of the ailment, though the availability of a range of drugs has meant that less than one in 1,000 now succumbs to the disease. However, scientists are still not clear how the parasites cause the infection and how they manage to hide within the body.

Two teams of scientists unveiled a new generation of programmable molecular machines that can seamlessly repair tiny but deadly errors in the genetic coding of living organisms.
Taken together, the technologies expand the reach and precision of gene-editing, and open a path to fixing mutations that cause genetic blindness, sickle-cell anaemia, cystic fibrosis, and thousands of other debilitating diseases.
One approach, called base editing, performs "chemical surgery" directly on DNA, permanently altering faulty segments without cutting into the genome's ladder-like structure.
The second technique corrects errors in another type of genetic material called RNA, where anomalies can also ruin health or lead to death.
First Method
The four chemical building blocks of DNA, called bases, are represented by the letters A, T, G and C, and always strung together in pairs -- "A" with "T", and "G" with "C".
All it takes is one pair in the wrong place -- a genetic mutation -- for things to go horribly wrong.
Another gene-editing tool already in wide use called CRISPR-cas9 cuts the DNA strand, typically to insert or delete a DNA base pair.
But the new editing technique makes changes without breaking the DNA's spiralling chain.
In a breakthrough last year, the research team showed how to swap a C-G for a T-A base pair.
Laboratories around the world successfully used the technique to fix so-called "point mutations" in organisms ranging from bacteria and corn to mice and human embryos. But only about 15 percent of point mutations in humans known to be linked with disease can be fixed this way till now.
The new tool -- dubbed "ABE" for Adenine Base Editor -- cleverly coaxes an A-T base pair into a G-C base pair, repairing a class of mutation that accounts for about half of the 32,000 known pathogenic point mutations in humans.
Not only did the procedure have a much higher success rate than other gene-editing techniques, there were virtually no side-effects, such as unwanted DNA duplications or deletions.
Second Method
The human genetic code is about 3 billion letters long.
That's a lot of information, and these "letters"-the genetic bases adenine, cytosine, thymine, and guanine-are stored in nearly every one of the cells that makes up your body in the form of DNA.
Now, scientists have devised a way to fix a certain class of genetic errors by re-shaping the very molecules that form the basis of the genetic code.
Researchers have modified CRISPR to edit the same types of errors out of RNA, which is closely related to DNA calling this new platform REPAIR.
The team genetically engineered an enzyme that literally rearranges the atoms of one kind of DNA base to turn it into another, all without disrupting the genetic material that surrounds it.
More than 50,000 human diseases, including sickle-cell anaemia and phenylketonuria, are the result of a single change in the genetic code-one letter out of three billion.
So it would be incredibly useful to have a technique whereby this so-called point mutation can be repaired without messing around too much with the surrounding DNA.

Harvard scientists have developed a next-generation hybrid version of RoboBee that can fly, dive into water, swim, propel itself back out of water, and land safely. The RoboBee is 1,000 times lighter than any previous aerial-to-aquatic robot, and could be used for numerous applications, from search-and-rescue operations to environmental monitoring and biological studies, researchers said. This is the first micro-robot capable of repeatedly moving in and through complex environments.

An organic filter that allows only near-infrared (NIR) light to pass through has been developed by scientists at the CSIR-National Institute for Interdisciplinary Science and Technology (CSIR-NIIST) based in Thiruvananthapuram. The new NIR filter can be used for night vision glasses, night photography, and will have applications in security and forensics such as identifying blood stains on a dark fabric. Currently available inorganic filters are expensive and brittle whereas organic filters are easy to process and flexible too. The filter was prepared by mixing a black dye (diketopyrrolopyrrole or DPP) having an amide group that helps the molecules to be in close contact with each other and interact, leading to changes in their optical properties. The organogel-based filter has the ability to absorb both ultraviolet and visible light while allowing the near-infrared light alone to pass through. The nanofibres formed through the self-assembly of the DPP molecules are responsible for the broad light absorption of the material, making it appear dark. How Scientists Developed It The researchers developed the filter by mixing the organogel with a transparent polymer (polydimethylsiloxane). The addition of the dye turns the transparent polymer into a semi-transparent one and the filter appears black as it absorbs most of the ultraviolet-visible light. Only very little of the organogel has to be added to the polymer to make the filter. The material is present throughout the polymer matrix even though very little is added. The filter was found to absorb light from 300-850 nm (both ultraviolet, visible and a part of NIR light) and transmit NIR light from 850-1500 nm. The researchers tested it for night photography and found the filter responsive only to NIR light. A potential application of the new material is in the design of hidden security codes on documents which can be viewed only through a NIR-readable camera.

Nasa's MAVEN (Mars Atmosphere and Volatile Evolution Mission) spacecraft, which has been orbiting Mars since 2014, has been gathering data that will allow scientists to understand changes in the upper atmosphere of the Red Planet. It is known that Mars, billions of years ago, had atmosphere and water and could have supported life. It is now barren and cold. What Mars now has is a thin atmosphere–and even this is at risk, say scientists who have discovered that the planet has a twisted tail. The process that created this tail could also allow some of Mars' already thin atmosphere to escape to space. Mars' magnetic tail, or magnetotail, is unique in the solar system. It's not like the magnetotail found at Venus, a planet with no magnetic field of its own, nor is it like Earth's, which is surrounded by its own internally generated magnetic field. Instead, it is a hybrid between the two. The team found that a process called "magnetic reconnection” must have a big role in creating the Martian magnetotail because, if reconnection were occurring, it would put the twist in the tail. A model the scientists built suggested that such reconnection would cause the planet's tail to twist 45 degrees from what is expected, based on the direction of the magnetic field carried by the solar wind, the scientist explained. The model was found to be in agreement with readings based on MAVEN data. Mars lost its global magnetic field billions of years ago and now just has remnant ‘fossil' magnetic fields embedded in certain regions of its surface. Mars' magnetotail is formed when magnetic fields carried by the solar wind join with the magnetic fields embedded in the Martian surface in a process called magnetic reconnection. The solar wind is a stream of electrically conducting gas continuously blowing from the Sun's surface into space at about one million miles (1.6 million kilometres) per hour. It carries magnetic fields from the Sun with it. If the solar wind field happens to be oriented in the opposite direction to a field in the Martian surface, the two fields join together in magnetic reconnection, such that the reconnection might propel some of the atmosphere of Mars into space. Mars' upper atmosphere has electrically charged particles (ions), which respond to electric and magnetic forces and flow along magnetic field lines. Since the Martian magnetotail is formed by linking surface magnetic fields to solar wind fields, ions in the Martian upper atmosphere have a pathway to space if they flow down the magnetotail. Like a stretched rubber band suddenly snapping to a new shape, magnetic reconnection also releases energy, which could actively propel ions in the Martian atmosphere down the magnetotail into space. MAVEN: Know More Mars Atmosphere and Volatile EvolutioN Mission (MAVEN)[5] is a space probe developed by NASA designed to study the Martian atmosphere while orbiting Mars. Mission goals include determining how the planet's atmosphere and water, presumed to have once been substantial, were lost over time. MAVEN was successfully launched aboard an Atlas V launch vehicle at the beginning of the first launch window on November 18, 2013. Following the first engine burn of the Centaur second stage, the vehicle coasted in low Earth orbit for 27 minutes before a second Centaur burn of five minutes to insert it into a heliocentric Mars transit orbit. On September 22, 2014, MAVEN reached Mars and was inserted into an areocentric elliptic orbit 6,200 km (3,900 mi) by 150 km (93 mi) above the planet's surface. The principal investigator for the spacecraft is Bruce Jakosky of the Laboratory for Atmospheric and Space Physics at the University of Colorado Boulder. On November 5, 2015, NASA announced that data from MAVEN shows that the deterioration of Mars' atmosphere increases significantly during solar storms. Mars' gradual shift from its carbon dioxide-dominated atmosphere-which had kept Mars relatively warm and allowed the planet to support liquid surface water-to the cold, arid planet took place between about 4.2 and 3.7 billion years ago.