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Kanpur Monday, 8 October, 2018 - 16:23

A study by researchers at the ICAR-Indian Institute of Pulses Research, Kanpur, has identified parts of the DNA in lentils that are associated with flowering. The research, published in the Journal of Applied Genetics, aims to help crop breeding programs to raise lentil varieties that mature early and has an excellent potential to yield in a short time.

Lentils (Lens culinaris) are highly nutritious pulses often associated with poor yield when there is a drought or an increase in the atmospheric temperature. In most parts of India, they are sown after the delayed harvest of the paddy crops. Thus, they get adversely affected by the rising summer temperatures and associated droughts during their seed-filling stage. This phenomenon can lead to reduced yield and inferior quality of the grains.

However, certain lentil varieties manage these problems by producing flowers sooner than average and hence, can provide a good yield in a short time and help in seasonal crop rotation. The researchers of this study have tried to identify the molecular factors associated with this phenomenon. The research was funded by the Department of Agriculture Cooperation and Farmers Welfare and the Department of Biotechnology.

A 'marker' is a DNA sequence in the genome which can be located easily and used to mark the position of a specific gene. The present study identifies ‘simple sequence repeat markers (SSR)’ in lentils that are associated with flowering. Also called microsatellites, they are short, repetitive sequences of nucleotides of the DNA, which is unique to every organism and occur multiple times in its genome. SSRs are used widely in the study of plant genomics, cancer diagnosis, paternity tests, and forensics.

The researchers used 96 types (accessions) of lentils for their study and classified them into two groups based on their flowering time. The first group contained plants with flowering time between 40-70 days and the second group contained plants that flowered in 54-69 days. The researchers then identified SSR markers present in all the 96 types of lentils. Interestingly, they found many markers that showed an association with the flowering time of lentil.

The study is a crucial step in developing a genomic resource for lentils, which is limited when compared to other major legume crops like soybean, pigeonpea and chickpea. “The markers developed in this study can be used as functional markers in the lentil breeding program to develop short duration cultivars,” say the researchers, commenting on the importance of this study.

Section: General, Science, Health, News Source: Link
Kanpur Sunday, 7 October, 2018 - 23:09

If you are tossing mutton bones into a bin right after a delicious biryani, think again. A novel idea by researchers from the Indian Institute of Technology Kanpur (IIT Kanpur) might take these bones straight into a research lab! In a study published in the Journal of Environmental Chemical Engineering, the researchers have, for the first time, developed a nanocatalyst using waste mutton bones. The bones serve as the photocatalytic support for titanium dioxide nanoparticles.

Photocatalysis is a process of acceleration of a chemical reaction by light. A classic example of this process is the use of sunlight by the green chlorophyll pigments in plants to convert water and carbon dioxide into oxygen and glucose. Titanium dioxide, a naturally occuring oxide of titanium, is also a photocatalyst since it can absorb light and propel a chemical reaction. Since it is very stable and resistant to corrosion, it is widely used as a photocatalyst to degrade organic pollutants into carbon dioxide and other compounds.

One approach to improving the efficiency of titanium dioxide as catalysts is to convert it into nanoparticles, nanorods or nanotubes as it increases their surface area. However, due to the tiny size, they tend to clump together, thus reducing their performance as a catalyst with time. “Besides, the recovery of the nanoparticles is also difficult at the end of the process. Hence, it is important to immobilise these nanoparticles on some support”, says Prof. Raju Kumar Gupta from IIT Kanpur, who is also an author of the study.

In the current study, the researchers have used mutton bones as a support material to immobilize these nanoparticles. Mutton bones are rich in a mineral known as hydroxyapatite, which is a form of calcium phosphate. It is non-toxic, thermally stable, has good adsorption capabilities and allows ion-exchange. Hence, it can be used as a low-cost biomaterial support for photocatalytic applications. The researchers of the study have incorporated titanium dioxide nanoparticles onto powdered bones to produce a novel nanocatalyst. “The mutton-derived hydroxyapatite material is derived from the waste and is cost-effective and reusable support", remarks Prof. Gupta.

The researchers tested the thermal stability of the nanocatalyst, its ability to absorb light and its molecular structure that helps photocatalysis. They also examined the reusability of the nanocatalyst. The analysis showed that the titanium dioxide nanoparticles are dispersed evenly over the hydroxyapatite derived from mutton bones, thus reducing the possibility of agglomeration of the titanium dioxide nanoparticles during the reaction.

“The hydroxyapatite support, derived from mutton bones, is beneficial for the immobilisation of the nanoparticles and for applications where properties of the materials are affected due to agglomeration”, comments Prof. Gupta about the findings.

The X-ray diffraction used to study the crystalline structure of the nanocatalyst revealed that hydroxyapatite was in hexagonal crystal structure and titanium dioxide was in anatase form, which absorbed UV light. The photocatalyst was found to work best under the UV light. After ten uses of the photocatalyst consecutively without regeneration step, its efficiency decreased only by 8.4%, thus making it eligible to be used multiple times without any significant changes in its morphology or crystal structure.

This research addresses the need for developing efficient and stable catalysts that can help us cope with the waste that we generate each day by treating them and degrading the pollutants rapidly. Isn't it fascinating to note that the bones that we dispose of as 'waste', could, in fact, help us manage our waste?

Section: General, Science, Health, Deep-dive Source: Link
Bengaluru Sunday, 7 October, 2018 - 07:28

The first week of October is observed in India as the ‘Wildlife Week’. On the global scenario, the past year has some good and bad news for wildlife— an increase in the number of mountain gorillas in Rwanda and Uganda, extinction of the Spix's macaw, a bird from the Amazon rainforests, and the only surviving male Northern white rhino in the world, breathed his last. Closer home, we recently lost over 20 lions in the Gir forest for reasons not yet known. So, how is India faring in conserving its wildlife? What are some of the challenges animals in the wild face?

India is the only country in the world that is home to three iconic species of cats—the Asiatic lion, the Bengal tiger and the Indian leopard. Unfortunately, all of them are classified as ‘threatened’ under the IUCN Red List. Thanks to successful conservation policies and efforts from the forest department, wildlife NGOs, researchers and conservationists in recent times, there has been an increase in the number of flagship species. For example, the number of estimated wild tigers in the country has increased from 1411 in 2006 to 2226 in 2014. However, the overall picture of the wildlife in the country still looks grim.

As a consequence of the urbanisation and development projects across the country, the size of our natural forests has been shrinking. A recent study from the Indian Institute of Science (IISc) showed that forest land in the district of Uttara Kannada had rapidly decreased from 57.31% in 1979 to 32.08 % in 2013. There is also the problem of roads fragmenting forests into disconnected islands. With the increase in population of wildlife and shrinking habitats, these animals are now venturing beyond the boundaries of protected areas or forests, into neighbouring villages and towns, leading to conflicts with humans. 

From crop-raiding elephants, nilgais and monkeys, to people being attacked by tigers, leopards, bears and snakes, we are at loggerheads with wildlife every day. On an average, in India, we kill over 80 elephants and 30 tigers every year through electrocution and road/train accidents amongst others, while one human is killed every day by elephants and tigers alone!

A recent example of such an escalated conflict can be seen in the hills around Pandharkawada, a town in Maharashtra, where a six-year-old tigress seems to have turned a ‘man-eater’. While officials claim that in the last two years she has killed at least five people, local reports claim the number could be well over 10. After several failed attempts to capture the tigress, who now has two cubs, the Supreme Court approved tranquilising the tigress by the forest department or to shoot her at sight. While this could solve the immediate problem at hand, is this really a solution to the bigger problem? No, say experts, calling such steps a shear failure of humanity.

Development projects in and around forests and wildlife corridors also pose a considerable conflict threat. The Yethinahole River Diversion project, which aims to pump water from the Western Ghats to other parts of the state, is located in the forests that are home to elephants, gaurs, leopards and other animals. Destruction of this habitat could lead to more human-animal conflicts in the future and result in the loss of both human and animal life. The rampant construction and mining activities in the periphery of the Bannerghatta National Park (BNP) near Bengaluru, has resulted in elephants often straying into surrounding villages. Thanks to the decision by the state’s Mines and Geology Department to close 15 mines in the region, the elephants are now back in BNP.

The state of Karnataka has a thriving wildlife population, with over 400 tigers and 6000 elephants—the highest in the country. A recent report says we also have over 2500 leopards in the state. Controlling this flourishing population poses a challenge.

“The biggest challenge for us is to protect wildlife outside protected areas. I would say that an equal number of tigers stay outside protected areas in Karnataka”, says Mr. Vijay Mohan Raj, Chief Conservator of Forests, Chikamagalur, who has been working towards conservation efforts here.

Wild ungulates, when found raiding crops, are often declared as ‘vermin’ and killed en-masse by poisoning, electrocution, and shooting. Crop-raiding elephants also often become the victim. There are already 14 elephant deaths in Karnataka by electrocution alone this year. Incentivising people in such wildlife conflict zones could help them tolerate such attacks. “We need to create a platform where insurance companies cover crop losses in areas where human-wildlife conflict occur. Right now, we only compensate ex-gratia. We need a system where people who suffer losses are compensated adequately”, opines Mr. Mohan Raj. The state Forest Department is currently testing a phone-based app for easy dispersal of compensation for affected people.

While the forest peripheries are mired in conflicts, how safe are wildlife sanctuaries in the wake of illegal poaching and other activities? “We have a very robust patrolling system. The Bhadra Tiger Reserve patrol, for example, collectively walks close to 6000 km a month. Every corner of the park is being patrolled, but there is scope for more protection especially with snares on the periphery laid out by farmers to protect their crops”, shares Mr. Mohan Raj.

Mr. CR Naik, a deputy Range Forest Officer at the Kali Tiger Reserve also believes that our wildlife is well protected within our sanctuaries. However, there is cause for worry when it comes to smaller fauna. “Most people only want to see charismatic species like tigers, leopards or black panthers (melanistic leopards) and in the process, the lesser-known but equally interesting animals like snakes, frogs and insects are often neglected”, he remarks. A study reported that amphibians comprise 50% of all roadkills in the Western Ghats.

Snake bites are one of the results of the increased human-animal conflicts. Last year, there were over 7600 cases of snake bites reported in Karnataka. There could also be many snakes killed due to fear and lack of awareness. In an attempt to change that, Mr. Naik and his staff at the Kali Tiger Reserve are rescuing over 500 snakes every year from settlements on the periphery of the reserve.

“A forest is like an open university with infinite knowledge for those who seek it”, says Mr. Naik, pointing out the wealth of information that exists in these green patches. This wildlife week is your opportunity to learn from Mother Nature and do your part in protecting our natural heritage. Step up, volunteer at your local wildlife NGO, take measures to save our forests or just spread the word!

Section: General, Science, Ecology, Deep-dive Source:
Mumbai Friday, 5 October, 2018 - 08:02

Imagine you book a cab using smartphone app, and it shows your cab is five minutes away. Five minutes are gone, and the app still says the same thing! Sounds familiar? While you could easily blame the rush hour traffic, did you know the culprit could also be the Global Positioning System (GPS) of your or your cab driver's phone? Yes, often phones fail to receive the GPS signal because of the interference from tall buildings. In a recent study, researchers from the Indian Institute of Technology Bombay (IIT Bombay) have designed a solution to improve the accuracy of the location in absence of GPS by making your phone communicate with other phones around.

The Global Positioning System (GPS) is a satellite-based navigation system where navigation signals from satellites are received by GPS receivers fitted in most smartphones available today. Unlike the cellular network that connects our phones to each other using nearby mobile towers, GPS relies solely on direct satellite signals. Although the location of a cell phone can be traced by correlating its signal strength and the distance to the nearby cell towers, this approach is inaccurate compared to GPS. However, GPS has its drawbacks too; besides consuming more power, it often fails to work in densely populated city centres with tall buildings, crowded public transport, or inside tunnels where it fails to catch the signals from the satellites.

In this study, the researchers propose a novel, crowdsourced application called CrowdLoc that makes the best use of the inaccurate location information using cellular technologies to improve the accuracy of the estimated location. Their research shows that the errors cancel out when location information from many nearby phones are combined.

“The main innovation in CrowdLoc is that it turns a 'crowd' into an advantage, by sharing information to improve location accuracy, even as the same 'crowd' makes GPS unreliable”, says Prof. Bhaskaran Raman from IIT Bombay who led the study. The findings of this research are published in ACM Transactions on Sensor Networks (TOSN), a reputed computer science journal.

When a phone has CrowdLoc installed, the algorithm in the application combines bare minimum information of its ‘location fingerprint’ along with such fingerprint of other phones with the same app installed, which are within a distance of five metres. The location fingerprint includes the identity of the closest cell tower, the signal strength and the GPS coordinates. Thus, those phones installed with CrowdLoc take part in 'crowdsensing', mutually helping each other to improve the accuracy of their respective locations.

But, what about the privacy, you ask? The 'location fingerprint' shared by CrowdLoc with other phones does not contain anything that uniquely identifies the owner of the phone! There is no personal information such as names or phone numbers that are shared. Also, the application sends the ‘location fingerprint’ every few seconds over an inaudible radio frequency. This approach is not only fast but also energy efficient. Thus, a phone can communicate with those nearby without turning on its Wifi or Bluetooth.

The researchers tested the application by collecting experimental data from two cities. They chose Mumbai because it is a large and densely populated metropolitan city with multiple means of transportation. The other city was Chandigarh, which is a smaller city with a well-planned road network. The researchers observed that their system worked well in spite of the loud, external audio noise of the vehicles, honking and people—a trait common in many metropolitan cities in the developing world. The accuracy of location as determined by the application was not affected even if the phones were of different brands, carry SIM cards from different operators, or have access to the Internet.

“Using CrowdLoc, we found that the median localization accuracy went from 97 metres to 33 metres over the traditional method of using cell-phone data alone. It works well in places where GPS is expensive or unavailable. We have the CrowdLoc prototype available as a module for use in other location-based apps”, says Ravi Bhandari, a PhD candidate at the Department of Computer Science and Engineering of IIT Bombay and one of the primary authors of this research.

The other advantage of the CrowdLoc application is that it does not have to process a massive amount of computationally intensive data to yield accurate results. It can work well even with two to four phones in the vicinity of your phone, with one of them having commuted in the same route at least once.

CrowdLoc could be a gamechanger in the public transport scenario in India, which are always crowded and the probability of a daily commuter in any given journey is high.

CrowdLoc could be used at many places where a little accuracy can be traded with seamless location availability and less energy usage. Examples of such applications could be predicting arrival time of crowded trains or buses, where GPS is unavailable most of the time. Another application could be a city-wide tourist application, where energy consumption of the application is a concern, but GPS-level accuracy is not required. For CrowdLoc to scale to other commuters, engaging incentive mechanisms tied to tangible/monetary rewards, have to be developed”, signs off Ravi.

Section: General, Science, Technology, Deep-dive Source: Link
Bengaluru Thursday, 4 October, 2018 - 18:18

In a recent study, published in the journal Emerging Microbes & Infections, a multi-national team of researchers have traced the trail of the Zika virus from the forests of Africa to India and other Asian countries. Considering the concerning recent media reports on the mass detection of Zika virus infection in Jaipur, India, this study may throw light on the evolution of the disease and help develop control strategies against the fatal virus.

The Zika virus was first detected in a rhesus monkey in the Zika forest of Uganda in 1947. One year later, the virus was discovered in a mosquito species Aedes africanus, indicating its circulation among mosquito and monkeys. The infection then gradually spread to other parts of Africa and reached Asia. As per the World Health Organization’s classification scheme on the prevalence of this virus, India is in category 2, indicating ongoing transmission of this virus.

The researchers of the current study analysed the genomic sequence of the causative virus to understand its evolutionary history and dispersal pattern. “Many new sequences are now available from Zika virus infected humans in Asia, including Bangladesh, India, Indonesia, the Philippines, Singapore, Thailand, and Vietnam. These sequences may impact our interpretation of the early evolutionary history of Zika virus in Asia. We, therefore, re-visited the evolutionary events of Zika virus from its first emergence in Asia”, say the authors, talking about the motivation behind the study.

The findings of the study reveal that the virus entered India later than some of the other countries in Asia. “The Zika virus was first introduced to Southeast Asia during the 1950s, which then dispersed both eastwards and westwards. It was potentially first introduced from Africa to the Malaysian–Indonesian region and subsequently to India”, explain the authors.

But, why is it that we do not see the virus turn into an epidemic for so long? “The very low frequency of clinically apparent Zika virus infections and the difficulty in clinically discriminating the Zika virus infection from the infections caused by Dengue, and chikungunya virus were major factors in the failure to recognize the presence of Zika infections,” opine the authors. They also suggest that the Asian population might have developed a herd (community) immunity to the virus.

The findings of the study can help policymakers and healthcare professionals to understand the disease in its entirety and devise appropriate control measures. “Our findings reveal new features of the evolution and dispersal of this intriguing virus and may benefit future disease control strategies,” the authors say. 

Section: General, Science, Health, Society, Policy, News Source: Link
Thursday, 4 October, 2018 - 07:35

संगीत वाद्ये, समुद्राच्या लाटा, गुरुत्वीय तरंग, अॅन्टेना आणि लंबक या सगळ्यांमध्ये सामायिक असलेला एक घटक म्हणजे या सर्वांचाच संबंध दोलनांशी (ऑसीलेशन्स) आहे. विविध दोलक एकत्र आल्यावर काय होते, हा प्रश्न महत्त्वाचा आहे. म्हणजे अनेक दोलक एकमेकांवर परिणाम करतील अशा पद्धतीने एकत्र आले तर काय होईल? भारतीय तंत्रज्ञान संस्था मुंबई येथील श्री तेजस कोतवाल यांनी चीन येथील बेहांग विद्यापीठाचे डॉ. झिन जियांग आणि नॉर्थवेस्टर्न विद्यापीठातील प्राध्यापक डॅनियल अब्राहम्स यांच्या सहकार्याने युग्मित दोलकांच्या कायमारा अवस्थेचे मूळ काय आहे याचे स्पष्टीकरण एका साध्या गणिती समीकरणाच्या  आधारे दिले आहे.

एकसारखे युग्मित दोलक (कपल्ड ऑसीलेटर्स ) असतील तर त्यांची दोलने एकतर वाट्टेल तशी होतील किंवा एकमेकांशी संपूर्णपणे सुसंगत अशी होतील, अशी एकविसाव्या शतकाच्या सुरुवातीला मोठ्या प्रमाणावर समजूत होती. मात्र नंतर असे दिसले की, काही विशिष्ट परिस्थितीत त्यातले काही दोलक लहानशा गटात एकमेकांशी सुसंगत वागतात तर काहींची दोलने कशीही होतात. जणू काही प्रत्येक गटाची एक स्वतंत्र ओळख असते. २००२ मध्ये लक्षात आलेल्या या विरोधाभासात्मक वर्तनाला “कायमारा अवस्था” असे म्हणतात. कवी होमरच्या इलियड या महाकाव्यात एकापेक्षा अधिक प्राण्यांनी बनलेल्या आणि आग ओकणाऱ्या कायमारा नावाच्या एका राक्षसी प्राण्याचे वर्णन येते. या प्राण्याचे धड सिंहाचे असून त्याच्या पाठीतून बकऱ्याचे डोके उगवल्यासारखे दिसते आणि शेपटी सापासारखी असते. त्याच्यावरूनच “कायमारा अवस्था” हे नाव पडले आहे. फिजिकल रिव्हयू लेटर्स या नियतकालिकात प्रसिद्ध झालेल्या शोधनिबंधात संशोधकांनी असे दाखवून दिले आहे की युग्मित दोलकांसाठी असलेली गणिती समीकरणे (प्रतिरूप) वापरून “कायमारा अवस्थेचे” मूळ समजून घेता येते.

त्यांच्या विश्लेषणाची सुरुवात होते ती कुरामोतो मॉडेल वापरून. “१९७० पासून कुरामोतो मॉडेल अस्तित्त्वात आहे. आत्तापर्यंत हजारो संशोधकांनी त्याचा वापर करून निसर्गातील गोष्टी एकमेकांशी सुसंगत कशा असतात ते समजून घेण्याचा प्रयत्न केला आहे. काजवे एकसाथ चमकतात, रातकिडे सुरात सूर मिसळून किरकिरतात, हृदयातल्या सगळ्या पेशी एकत्र आकुंचन पावून रक्ताला वाट करून देतात इत्यादी काही उदाहरणे. हे मॉडेल आवश्यक तितके क्लिष्ट असले तरी साधे पेन आणि कागद घेऊनही सोडवता येण्यासारखे आहे.” असे या शोधनिबंधाचे सहलेखक असलेले नॉर्थवेस्टर्न विद्यापीठाचे प्राध्यापक डॅनियल अब्राहम्स म्हणतात. “इतक्या अरेषीय आणि निश्चित उकल असलेल्या” समीकरणांचा हा दुर्मिळ संयोग म्हणजे कोणत्याही सैद्धांतिक गणितज्ञाचे स्वप्न सत्यात उतरल्यासारखेच आहे.

दोलकांची नैसर्गिक वारंवारिता, त्यांच्यातील युग्मतेची बळकटी आणि त्यांच्य प्रावस्थेत (फेज) असलेला फरक अशा विविध घटकात बदल झाले असता कुरामोतो मॉडेलमध्ये काय बदल घडून येतात याचा संशोधकांनी अभ्यास केला. “या शोधनिबंधातील महत्त्वाचा मुद्दा म्हणजे कुरामोतो सुसंगत अवस्थेतून पिचफोर्क (द्विशूल) द्विभाजानाद्वारे कायमारा अवस्था गाठता येते. कायमारा अवस्था तयार होणे हा निखालसपणे सममिती बिघडण्याचा (सिमेट्री ब्रेकिंग) प्रकार आहे असे आमच्या विश्लेषणातून दिसते.” असे या शोधनिबंधाचे प्रथम लेखक, आयआयटी मुंबईचे तेजस कोतवाल सांगतात.

एखादी प्रणाली नियंत्रित करणाऱ्या इनपुटपैकी एखादे इनपुट सावकाश बदलत नेले असता त्या प्रणालीत अचानकपणे जो नाट्यमय बदल घडून येतो त्याचे वर्णन करण्यासाठी “द्विभाजन” ही संज्ञा गणिती अर्थाने वापरली जाते. उदाहरणार्थ, पाण्याचे तापमान सावकाश वाढवत नेले असता, ते १०० अंश सेल्सियसला पोहोचल्यावर पाण्याचे रुपांतर अचानक द्रवस्थितीतून वायुस्थितीत होते. पिचफोर्क द्विभाजानात नियंत्रण करणारे इनपुट सावकाश बदलत द्विभाजन उंबरठ्यापलीकडे नेले असता, त्या प्रणालीतील समतोलाची एक अवस्था जाऊन त्याऐवजी तिला दोन समतोल अवस्था प्राप्त होतात आणि या दोन्ही अवस्था मूळ समतोल अवस्थेपेक्षा वेगळ्या असतात. मूळ समतोल अवस्था नाहीशी होते. (म्हणजेच ती अवस्था स्थिर राहत नाही.) “युग्मित दोलकाच्या उदाहरणात, नियंत्रित करणारे घटक सावकाशपणे बदलत नेले असता एका समतोल अवस्थेकडून, म्हणजेच संपूर्णपणे सुसंगत अवस्थेकडून दोन वेगेवेगळ्या स्थिर संतुलित अवस्थांकडे, म्हणजेच दोन प्रकारच्या कायमारा अवस्थेकडे जाता येते.” असे प्राध्यापक अब्राहम्स सांगतात.

‘सममिती बिघडणे’ ही संकल्पनादेखील एका साध्याशा उदाहरणाने समजून घेता येईल. अशी कल्पना करा की, एखादी पेन्सिल तिच्या टोकावर तोल साधून उभी आहे. ती एकदम संतुलित अवस्थेत असली तरीही कोणत्या ना कोणत्या बाजूला पडणारच आहे. निसर्गनियमानुसार ती एखाद्या विशिष्ट बाजूलाच पडेल असे नाही. मात्र एकदा का तिचा तोल ढळला की ती एखाद्या दिशेला पडते आणि सममिती बिघडली असे आपण म्हणतो. कायमारा अवस्था तयार होणे हा सममिती बिघडण्याचाच एक प्रकार आहे का हे याआधीच्या अभ्यासातून स्पष्ट झाले नव्हते. तसेच कायमारा अवस्था आणि संपूर्ण सुसंगत अवस्था यातील ठळक संबंधही दिसला नव्हता. मात्र, वरील अभ्यासातून कायमारा अवस्था जाणून घेणे आणि या अवस्था कुठून निर्माण होतात ते समजणे शक्य होते.

या संशोधनाचा वापर कुठे होऊ शकतो याबद्दल बोलताना श्री. कोतवाल म्हणतात, “या मॉडेलच्या मांडणीचा उपयोग रासायनिक आणि जैविक दोलकांच्या किंवा लेझर आणि यांत्रिक लंबकांच्या प्रणाली कशा चालतात हे विशद करण्यासाठी होऊ शकतो. चेतासंस्थाशास्त्रात आणि हृदयाच्या पेशींच्या हालचाली समजून घेण्यासाठी देखील या अभ्यासाचा बराच उपयोग होऊ शकतो.”

Section: General, Science, Deep-dive Source:
Germany Wednesday, 3 October, 2018 - 18:10

In a recent finding that could unveil a hitherto unknown function of the South Asian monsoon, researchers from Germany and Cyprus have described how the South Asian monsoon plays an active role in regulating the levels of pollutants in the atmosphere. While we knew that the monsoon rains brought a much-needed relief during the hot summer months, and fuelled our agriculture activities, this discovery could help understand the implications of monsoon on the pollutants in the atmosphere.

The word ‘monsoon’, derived from the Arabic word mausam or season, is a seasonal change in the direction of the prevailing winds in a region. The South Asian summer monsoon is marked by heavy rainfall during the months of May-September, followed by a dry winter monsoon. Although we knew about the winter haze or ‘atmospheric brown cloud’ that formed due to vehicular emissions and crop burning, there was no explanation for the disappearance of the haze when the rainy summer monsoon arrived, until now.

In the current study, published in the journal Science, the researchers conducted an elaborate experiment to explore the reasons behind this phenomenon. They studied and measured atmospheric pollutants using a High Altitude and Long Range research aircraft (HALO) at an altitude of 9-15 km during July and August 2015. They analysed their measurements by combining it with computer models for air circulation and tracked the path and fate of the pollutants.

The researchers found that the South Asian monsoon acted as a natural air purifier. The rains removed a considerable fraction of the pollutants and their oxides. For example, nearly 80% of the reactive sulphur emissions in South Asia were found to be removed by precipitation. However, on the flip side, the researchers found that the monsoon was responsible for spreading the pollutants from South East Asia to all over the world.

So, how does the cleaning action of the monsoon work? Above the stormy monsoon clouds, there exists a region of high atmospheric pressure called the anticyclone. When large amounts of pollutants in the atmosphere reach this layer, they are distributed globally.

“South Asian emissions dominate pollution concentrations in the anticyclone. Once in the upper troposphere, in the absence of deposition processes, pollutants accumulate and are chemically processed in a reactive reservoir for weeks to more than a month, from where carbonaceous, sulphur, nitrogen and halogen-containing reaction products disperse globally”, explain the authors.

Pointing out the two opposite roles of the South Asian monsoon, the researchers say, “the monsoon has two faces, like a Janus’ head—transferring pollutants from the surface upward while sustaining an effective cleansing mechanism that curbs the impacts.” With the burden of pollutants proliferating, the researchers believe that the South Asian emissions will intensify the flux of pollutants through the anticyclone in the years to come.

Section: General, Science, News Source: Link
Bengaluru Wednesday, 3 October, 2018 - 00:24

Agriculture, the backbone of the Indian economy, is a water-intensive activity. The numerous hunger strikes, protests and petitions from the farming community always have water at the centre of it. With water getting scarcer by the day, intelligent crop choices and sustainable irrigation methods although seem to be the obvious way forward, some farmers in the peri-urban regions of Bengaluru may not think so, reveals a new study.

The study, published in the journal Irrigation and Drainage, and carried out by researchers from the Ashoka Trust for Research in Ecology and the Environment (ATREE) finds that various factors affect the choice of crops by farmers and water usage in the Arkavathy river basin. The study finds that these choices depend on the proximity to urban areas, the economic status and caste of the farmer, non-agricultural employment opportunities in the vicinity and the incentives for water conservation.

The present study is part of a bigger, socio-hydrological research project that covers the Arkavathy and Noyyal sub-basins, both part of the larger Cauvery river basin. The areas around these two river basins are witnessing rapid urbanisation. The Arkavathy sub-basin has a catchment area of 4169 square kilometres with about 35% of Bangalore city falling in it. The study, conducted between 2012 and 2016, used a stratified random sample of 333 farmers from 15 villages.

“The Arkavathy sub-basin used to be the primary source of water for Bangalore until the 1970s before the city began to expand and depend on Cauvery for its water supply”, explains Dr Bejoy Thomas Fellow (Associate Professor), Convenor - Centre for Environment and Development, ATREE, who designed and led the study. However, the same region is now witnessing declining water levels and rampant water scarcity.

Local communities and decision makers blame the changing climate for the water woes in this region. However, the researchers of the study claim that the bad management of water resources is the real culprit. “The analysis of household and plot level survey data pertaining to drilled and non-functional borewells, the depth at which water was sighted, and changes in the cropping pattern between 1993 and 2013 shows that human-induced factors, including shift to eucalyptus plantations and groundwater pumping, were responsible for the water stress, which began to be felt since the mid 1990s”, says Dr Thomas.

The study uncovered interesting trends in the drilling of borewells and the choice of crops grown by the farmers of the region. Most borewells were found to be owned by wealthy, educated farmers belonging to the upper-caste and those living closer to the city. Those farmers without borewells depended on the rains for irrigation, and practised subsistence farming, or opted for employment in the non-agricultural sector, bidding goodbye to agriculture entirely.

The farmers who lived closer to the city and had borewells grew vegetables since it was easier to cater to the market demands of the urban area. Those who lived farther chose eucalyptus plantations as a lucrative option. The interesting point in these crop choices is that both are high on water consumption.

The study also reveals that only 37% of the farmers with irrigation facilities adopted drip irrigation. Drip irrigation, is an irrigation technique that allows water to drip slowly to the roots of the plants, is the most water-saving technique compared to others for irrigation. The government also provides a subsidy for the same. However, the farmers had other reasons to not adopting drip irrigation, according to the researchers. The drip technology is not suited for all crops grown in the region and the salt deposition, due to hard water, clogged the holes in the drippers, creating problems and discouraging its adoption.   

Besides, although farmers were aware of the water problems, they were not concerned about water conservation. “The farmers are aware of the groundwater problem, but there are no sufficient incentives, concerning the prices or opportunities for them to conserve it”, argues Dr Thomas. Hence, most adopted a 'drill deeper and quit' strategy, where they would dig up deep borewells and abandon irrigated agriculture when water was insufficient.

The study indicates that farmers are not worried about resource sustainability in the short run since there are much better, income generation opportunities outside of agriculture. As a start, placing some regulations on the use of groundwater could help resource sustainability, they say.  What could be a long-term solution? "Researchers, civil society groups, government departments and farmers should work together to reduce the impact of crop choices on water resources and make peri-urban agriculture an attractive livelihoods option", signs off Dr Thomas.

Section: General, Science, Deep-dive Source: Link
Pune Monday, 1 October, 2018 - 15:54

Toxic emissions from power plants in India and China are choking the air, finds a new collaborative study by researchers from the USA, India and China. The study, published in the journal Environment International, has detailed the health risks posed by these emissions and their impacts on the mortality and life expectancy of people living in both the countries.

Electricity has become an integral part of our lives. From our tiny gadgets to the numerous industries, all run on electricity. Power plants generate electric power from different energy sources like coal, gas, and oil, which not only power our lives but also spew a broad range of hazardous pollutants, including particulate matter. Particulate matter (PM) is a mixture of tiny particles and droplets in the air consisting of metals, dust, and organic compounds.

The researchers of the current study focused on understanding how the emissions from the power plants are contributing towards the rise in the level of a type of particulate matter called PM2.5. PM2.5 is a tiny atmospheric particulate matter with a diameter less than 2.5 micrometres—about 3% the thickness of human hair. It can penetrate into our lungs and impair their function. There are many studies that associate PM2.5 with premature deaths from lung cancer, pulmonary, and heart diseases. The current study measured the annual mean concentration of PM2.5 using a state-of-the-art model called WRF-Chem (Weather Research Forecasting model coupled with Chemistry), a model for the investigation of air quality.

The outcome of the study is alarming as it indicates that the pollutants are reducing our average life expectancy. The years of life lost (YLL) is a measurement of premature mortality and indicates the average years a person would have lived if he or she had not died prematurely. The researchers calculated that if we can eliminate the emissions from the power plants, we would be able to reduce 15 and 11 million years of life lost annually in China and India respectively.

The alarming findings of the study can guide policymakers attempting to identify efficient mitigation strategies to curtail pollution by particulate matter. “Priorities in upgrading existing power generating technologies should be given to Shandong, Henan, and Sichuan provinces in China, and Uttar Pradesh state in India due to their dominant contributions to the current health risks”, say the authors, proposing a few measures to address this problem.  

Section: General, Science, Health, News Source: Link
Bengaluru Monday, 1 October, 2018 - 15:39

Science relies on experiment and observation of nature to determine the truth or falsity of models and theories. But, the evaluation of individual performance in the scientific community is fraught with difficulty. Historically, scientific research was evaluated based on the opinions of fellow scientists. Now, with the increasing availability of quantitative data and electronic databases that can store them, these subjective criteria are being replaced by seemingly objective criteria. In India, metrics like the 'impact factor' of a journal and the 'h-index' are increasingly being used to determine appointments and promotions.

However, are these indices infallible? If not, is it time to revise these standards? In a study, published in the Indian Journal of Medical Ethics, scientists from the Department of Science and Technology (DST)'s Centre for Policy Research, the Indian Institute of Science (IISc), Bengaluru, and Council of Scientific and Industrial Research (CSIR) - Central Electrochemical Research Institute, Karaikudi, have examined these popular measurement standards and their trustworthiness.

The impact factor of a journal is a measure of the average number of citations that papers in a journal receive. Journals typically have a mix of highly-cited and less-cited papers, which together produce an average. But, does this average speak about the quality of the research? An example cited by the authors of the current study is of the renowned journal Nature, where 1% of papers account for nearly 12% of all citations. Many other published papers are either cited less or go uncited. Hence, they argue that the impact factor of a journal cannot be attributed to an individual paper published in that journal. Besides, research papers in fields like biomedicine tend to receive more citations compared to areas like mathematics and agriculture.

The h-index, on the other hand, is a metric based on the number of papers published by a researcher and the number of citations they receive. For example, a researcher’s h-index is 10 if they have ten papers cited 10 or more times. The metric depends only on the papers a researcher has published, not the journal. Does that make it a better measure? Not necessarily, say the authors of this study.

“The index does not take into account the actual number of citations received by each paper even if these are far in excess of the number equivalent to the h-index and can thus lead to misleading conclusions”, says Dr.Subbiah Gunasekaran from CSIR-CERI, who is an author of the study. Also, if a researcher has highly-regarded, groundbreaking research with a very high number of citations, that too is not taken into account. Also, it still suffers from the problem that the average number of citations per paper depends on the field of study. The Stanford University chemist Zare believes that the h-index is a poor measure in judging researchers early in their career, and it is more a trailing, rather than a leading, indicator of professional success.

Interestingly, there have been warnings about the misuse of these metrics from the time they were developed and published. For example, the Joint Committee report on Quantitative Assessment of Research formed by three international mathematics institutions cautioned that these metrics “should be used properly, interpreted with caution,” and went on to call the h-index a “naïve and poor measure in judging a researcher”. Eugene Garfield, a founding father of scientometrics (the study of measuring and analysing science) and the creator of the Science Citation Index (SCI) warned against “the possible promiscuous and careless use of quantitative citation data for sociological evaluations, including personnel and fellowship selection.”

Unfortunately, Indian regulatory and funding agencies have institutionalised such misuse. In addition to academic and research institutions, peer-review committees have also begun to use these metrics to rank researchers and institutions. Some establishments such as the Indian Institute of Management, Bengaluru, are giving out monetary rewards to researchers who publish in high impact factor journals. The Department of Science and Technology (DST) uses the h-index to evaluate universities, although it is a measure of the productivity of an individual researcher, and often, the h-index of a university may be determined by the work of a small number of individuals in one or two departments. Others like the University Grants Commission (UGC), Indian Council of Medical Research (ICMR) and the Medical Council of India use impact factors to select researchers and scientists for fellowships, for the selection and promotion of faculty, and for sanctioning grants to departments and institutions.

The UGC has mandated that universities and colleges apply a particular quantitative metric to evaluate aspiring faculty and existing faculty that is heavily based on impact factors of journals. Such a process can lead to arbitrariness in recruitment and evaluation practices. “If we compromise on the selection of researchers for jobs and decide to fund based on citation-based indicators in an uninformed way, obviously, there is every possibility that it would affect quality of research performed at Indian universities and laboratories”, says Dr. Muthu Madan from the Centre for Policy Research at IISc, who is an author of this study. These problems are further exacerbated because many supposedly “reputed” and “refereed” Indian journals are substandard and predatory, making India the world’s capital for predatory journals. Such policies help to breed and sustain predatory journals.

Even if there is no misuse of these metrics, they still have their limitations, say the authors. Research activity is not reducible to quantitative metrics like the h-index, impact factor or the number of papers published. These only seek to measure productivity without reference to creativity and originality, which the education system must encourage. As an example of the shortcomings of pure, scientometric based evaluations, Nobel laureates like Peter Higgs of Higgs Boson fame and Ed Lewis would have been rated as poor performers by these metrics. Additionally, an evaluation process based on scientometrics, like the National Institutional Ranking Framework (NIRF) instituted by the Ministry of Human Resource Development (MHRD), is liable to “gaming”, and research driven by assessment and performance targets.

Internationally, promotion and selection of faculty members is based on a combination of peer-review and metrics, with the balance determined by costs and academic traditions in each place. However, generally, the process is weighted more towards peer-review as opposed to the reliance on quantitative metrics. For example, Stanford University solicits the views of 10-15 national and international external experts to evaluate the research contribution of a faculty member. In India too, some institutions like the National Centre for Biological Sciences (NCBS) and the Indian Institute of Science (IISc) place heavy reliance on the opinions of peers. However, since peer-reviews are expensive, the authors of the study feel that the costs of rolling out such a system across the nation would be prohibitive.

The study calls for greater transparency and accountability in the process of assessment, and for giving greater importance to originality and creativity in evaluating performance and proposals. It finds that the method of assessing institutions, and the appointment of faculty, directors and vice-chancellors is mired in corruption, nepotism and political favouritism. The need of the hour is to clean up and depoliticise regulatory bodies like the UGC, All India Council for Technical Education (AICTE) and National Assessment and Accreditation Council (NAAC). The problems are less with the tools, and more with the agencies that govern and oversee academic institutions and research. In summary, the evaluation of researchers is not being done right in India at present, conclude the authors.

Section: General, Science, Society, Policy, Deep-dive Source: Link

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