(FREE) UPSC Current Affairs 2024 PDF

(Current Affairs) Science & Technology, Defence, Environment | August : 2017

Science & Technology, Defense, Environment

Sxientists have used a novel approach to drug discovery (Free Available)
Economic and Environmental analysis of Tiger reserves (Free Available)
Kumaon”). Its flow benefit per year is Rs 14.7 billion (Rs 1.14 lakhs per hectare). (Free Available)
NASA’s Hubble Space Telescope has beamed back images Phobos (Free Available)
Low-cost smart glove that can wirelessly translate sign language (Free Available)
Scientists found a galaxy 10 thousand million light years away (Free Available)
The marine ecosystems of eastern Arabian Sea to be studied (Only for Online Coaching Members)
Antarctica’s ice-free islands set to grow (Only for Online Coaching Members)
Scientists have developed a new non-toxic material (Only for Online Coaching Members)

Sxientists have used a novel approach to drug discovery

Scientists have used a novel approach to drug discovery by attaching or linking a DNA sequence of interest to gold-coated magnetic nanoparticles and picking those molecules that target and bind to the DNA sequence for further study.
This approach helps in rapid identification of potential DNA binding molecules for cancer therapy. G-quadruplexes are four-stranded DNA structures found in human genome, for example, the presence of G-quadruplexes in cancer-causing gene c-MYC.
Since G-quadruplexes are involved in regulation of the gene expression, there is increased interest in finding molecules that target them.
The traditional approach is to synthesise compounds and study their interactions with drug targets before choosing the best drug molecules. This is both time consuming and laborious.
The azide and alkyne fragments that are capable of binding to the adjacent sites of the G-quadruplex react with each other to produce triazole products. Theoretically, the combination of azide and alkyne fragments can generate 66 triazole products.
When the nanoparticles are heated, the triazole products that are bound to the G-quadruplex target get detached and get into solution. Since the DNA-linked, gold-coated magnetic nanoparticles are used, they can be separated from the solution using magnetic separation.
The researchers found that of the three triazole compounds that selectively bound to the G-quadruplex target, one (Tz 1) was found in large proportion and was the only molecule that was obtained when the nanoparticle was recycled for the fourth and fifth time.
Though this study is a proof-of-concept, this approach can be used for economical and fast screening of potential drug candidates for other DNA targets, RNA and even proteins.

Economic and Environmental analysis of Tiger reserves

The headline in a recent PTI report “Saving 2 tigers gives more value than Mangalyaan”’ was intriguing, since it said that saving two tigers yields a capital benefit of Rs 520 crores, while Mangalyaan cost us Rs 450 crores.
Putting a price on Nature and commodifying it may hurt our sensibilities. On the other hand, the authors of the above paper point out that an economic analysis helps in determining the quantity of goods such as fuel wood, and fodder that can be allowed for extraction by local communities, based on trade-offs with other services.
Such economic analysis also highlights why such “large” areas are reserved for preserving fierce animals like the tiger, when we need more land for human use.
What is the total amount of land set apart for the 18 ranges as tiger reserves? It is 68,000 square km, which is about 2% of the area of India – set apart for the nation’s pride animal. A tiger reserve is not just for the tiger.
The six reserves (Corbett, Kanha, Kaziranga, Periyar, Ranthambore, Sunderbans) that the team has studied house many other animals such as the elephant, rhino, langur, barasingha, mongoose, river dolphin, olive ridley turtle, crocodile — not to speak of the millions of herbs, plants and trees.
The approach, termed VALUE+, that the group uses has two components. The VALUE part indicates that the annual cost of putting together and maintaining the above six tiger reserves is about Rs 23 crores.
But then, what about the “flow benefits”? Take the Periyar Tiger Reserve as an example. VALUE estimates that this Reserve generates Rs 17.6 billion (or Rs 1.9 lakhs per hectare) per year.
How? For example it helps provide water to Tamilnadu districts, amount to Rs 4.05 billions /year. Or, take the famous Corbett Park (which is supposed to have the “maneaters of

Low-cost smart glove that can wirelessly translate sign language

Scientists have created a low-cost smart glove that can wirelessly translate sign language into text and control objects in virtual reality games.
The device, called “The Language of Glove”, was built for less than $100 using stretchable and printable electronics that are inexpensive, commercially available and easy to assemble.
The team built the device using a leather athletic glove and adhered nine stretchable sensors to the back at the knuckles — two on each finger and one on the thumb.
Stainless steel thread connects each of the sensors to a low power, custom-made printed circuit board that’s attached to the back of the wrist. The sensors change their electrical resistance when stretched or bent.
This allows them to code for different letters of the American Sign Language alphabet based on the positions of all nine knuckles.
A straight or relaxed knuckle is encoded as “0” and a bent knuckle is encoded as “1.” When signing a letter, the glove creates a nine-digit binary key that translates into that letter.
For example, the code for the letter “A” (thumb straight, all other fingers curled) is “011111111” while the code for “B” (thumb bent, all other fingers straight) is “100000000.”
The low-power printed circuit board on the glove converts the nine-digit key into a letter and then transmits the signals via Bluetooth to a smartphone or computer screen.

Antarctica’s ice-free islands set to grow

Scattered within the vast frozen expanse of Antarctica are isolated ice-free nooks — nunataks (exposed mountain tops), scree slopes, cliffs, valleys and coastal oases — which cover less than 1% of the area, but support almost all of the continent’s biodiversity.
But by the turn of the century these ice-free islands could grow by over 17,000 sq.km (a 25% increase) due to climate change, according to a paper published in Nature.
While this may sound like good news for Antarctica's biodiversity that is likely to find larger habitats, “it is not known if the potential negative impacts will outweigh the benefits,” the authors say.
As ice-free islands expand and coalesce, biodiversity could homogenise, less competitive species could go extinct and ecosystems destabilise from the spread of invasive species, which already pose a threat to native species.
Much life thrives in Antarctica's ice-free pockets: small invertebrates (nematodes, springtails, and tardigrades) vascular plants, lichen, fungi, mosses and algae.
They also serve as breeding ground for sea birds (including the Adelie penguins) and elephant seals.
The greatest change in climate is projected for the Antarctic Peninsula by the end of the century, and more than 85% of the new ice-free area is believed to occur in the north Antarctic Peninsula.