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Mumbai Monday, 26 March, 2018 - 11:03

Microbial Fuel Cells (MFCs) are bio-electrochemical devices that use the power of respiring microbes to convert organic matter into electrical energy. Thus, they can help treat wastewater and also generate electricity. Realising the vast potential these cells have, scientists are finding ways to improve their performance and efficiency. In one such effort, scientists from the Indian Institute of Technology Bombay (IITB) have demonstrated how stainless steel wool, coated with conducting polymers, could be used in microbial fuel cells to improve their performance.

Microbial fuel cells work by the action of microorganisms, which digest organic matter. In the presence of oxygen, this process produces carbon dioxide and water. However, in the absence of oxygen, as seen in sewage treatment plants and industrial effluent discharge, the process produces carbon dioxide, electrons and protons. Electricity is produced when these electrons are captured using electrodes. Hence, one way to improve the performance of the fuel cells is to use a better material for electrodes.

In this study, researchers have demonstrated, for the first time, the use of low-cost stainless steel wool as an efficient material for one of the electrodes (anode) used in fuel cells. They found that using stainless steel wool resulted in a 70% increase in power density (the amount of power per unit volume), as compared to stainless steel tubes, when used as an anode. Further, they observed that steel wool, when coated with conductive polymers like polyaniline and polypyrrole, performed twice as better than plain steel wool.

With more suitable materials and efficient design, MFCs could be our solution to waste management with energy generation in the future.
 

Section: General, Science, Technology, News Source: Link
Mumbai Monday, 26 March, 2018 - 08:27

Urban-rural transition zones are a breeding ground for unexpected changes in resources and livelihood, shows study from IIT Bombay.

Increasing demand for space in cities are forcing people to move to surrounding rural regions, which are more affordable. These areas, called peri-urban regions, have a mix of rural and urban elements. In a study, researchers from the Indian Institute of Technology Bombay (IIT Bombay) have observed that the natural resources were stressed and livelihoods changed to non-agricultural means in the  peri-urban regions around Mumbai.

Developing peri-urban regions without proper planning can bring trouble since vast agricultural areas are modified to suit urban needs. They differ from urban sprawls that are unplanned, scattered expansion of urban residential areas, in that peri-urban regions still maintain rural components like open land and farming.  In this process, natural resources like water are abused, primary occupations of locals undergo change, and ecosystems are damaged. “It is high time that peri-urbanisation in India is studied from the vantage point of the peri-urban regions, and not as an extended issue of urban management challenges”, says Prof. T.I. Eldho from the Civil Engineering Department, who led the study.

The researchers of the study focused on four peripheral villages of Greater Mumbai-- Mangaon Tarf Wasare, Mulgaon Tarf Wasare, Kondhane and Salpe of the Karjat sub-district. They used census reports for the years 2001 and 2011, surveyed 40 respondents with specifically designed questionnaire, and conducted group discussions with village heads to understand the demographic and livelihood details, and land and water usage.

The study found that agriculture, which was a main livelihood occupation, nose-dived from 20% in 2001 to 9% in 2011. It was now perceived as a marginal occupation as agricultural lands were now in the hands of private players, unlike land acquisition by the state. This also impacted farmers who cultivated their own land or tilled others’ lands. They now work as informal labourers at brick kilns or engage in small scale sand mining in the riverbed. . What was once their farms, had now turned into farmhouses, event venues and weekend getaways for the rich.

Brick kilns, often illegal, have now cropped up in large numbers. The study found that in addition to acting as an informal employer, the brick kilns now supply raw material to the growing construction in these areas. In the process, they pollute the environment, demand a constant supply of water and place a considerable strain on other natural resources in the peri-urban regions.

Acute shortage of water is another growing concern in the four peri-urban areas, the study found. Despite receiving an average annual rainfall of 3691 mm, thrice the national average, these villages faced chronic water shortage right after monsoon. Individual borewells, dug up in farmhouses and resorts, for their upkeep and to water orchard crops like mango, has resulted in depleting groundwater. Open wells, which once used to be the main source of water for the locals, including tribals, have all dried up. This has led to informal groundwater markets in the villages. Dams and water diversions that are planned, cater only to the urban needs, worsening the situation.

So, can’t these villages stand for themselves? “The existing local self-governments are weak, statutory bodies that are brutally set aside in times of actual decision making”, remarks Prof. Eldho, who believes that these peri-urban regions are not ‘passive recipients’ of the ‘development’ forced down their throats. “There is a strong agency at work here”, he says. The fact that these peri-urban zones lie outside the administrative boundaries of the urban city, often administrative confusions could lead to blame games. We can only make a difference when these dynamics are well-understood.

With our cities expanding at a rapid pace, peri-urbanisation of the bordering villages are here to stay. However, we can manage this process better, say the authors, who push for approaches away from conventional urban-centric policies. “The major pitfall of urban-centric policies is just that; they tend to implicitly assume that all peri-urban regions can be better governed through better management of urban concerns and better urban space planning”, opines Prof. Eldho. “We need long-term, interactive and decentralised mechanisms that help decrease the power differentials between these villages and the urban core”, he adds.

The Government of India has sought to address the concerns of peri-urbanisation with its National Rurban Mission. But Prof. Eldho is cautiously optimistic. “It is a step in the right direction if implemented with strong decentralization and participatory governance mechanisms, especially with regard to natural resource management”, he says.

The cities will continue to expand and we will continue to see the changes. However, we are better off not getting lost in this transition.
 

Section: General, Science, Society, Deep-dive Source:
Kodaikanal Saturday, 24 March, 2018 - 18:00

ಅನೇಕ ಪ್ರವಾಸಿಗರ ಪಾಲಿಗೆ ಪಶ್ಚಿಮ ಘಟ್ಟಗಳೆಂದರೆ ರಮಣೀಯ ಪ್ರವಾಸಿ ತಾಣವಷ್ಟೇ. ಆದರೆ, ಇವುಗಳಿಗೆ ಅದಕ್ಕಿಂತಲೂ ಹೆಚ್ಚು ಮಾನ್ಯತೆ, ಪ್ರಾಮುಖ್ಯ ಇದೆ. ವಿಶ್ವದ ಜೀವ ವೈವಿಧ್ಯ ಸಂಪದ್ಭರಿತವಾಗಿರುವ ಎಂಟು ಅತ್ಯಂತ ಪ್ರಮುಖ ತಾಣಗಳಲ್ಲಿ ಪಶ್ಚಿಮ ಘಟ್ಟ ಶ್ರೇಣಿಯೂ ಒಂದು. ಈ ಗಿರಿ ಶ್ರೇಣಿ ಬಗೆಬಗೆಯ ಕಾಡುಗಳು ಮತ್ತು ಹುಲ್ಲುಗಾವಲುಗಳನ್ನು ಒಳಗೊಂಡ ಮಹತ್ತರ ನೈಸರ್ಗಿಕ ಪರಿಸರ ವ್ಯವಸ್ಥೆಯನ್ನು ಹೊಂದಿದೆ ಎಂಬುದು ಇದರರ್ಥ. ಊಹಿಸಲಾಗದಷ್ಟು ಸಂಖ್ಯೆಯ ಸಸ್ಯ ಮತ್ತು ಪ್ರಾಣಿ ಪ್ರಭೇದಗಳು ಇಲ್ಲಿವೆ. ಅಷ್ಟೇ ಅಲ್ಲ, ಭಾರತೀಯ ಮಳೆಗಾಲವನ್ನು ಕಾಪಾಡಿಕೊಳ್ಳುವಲ್ಲಿಯೂ ಇವುಗಳ ಪಾತ್ರ ಪ್ರಮುಖವಾದುದು.

ಆದರೂ, ಇತ್ತೀಚಿನ ವರ್ಷಗಳಲ್ಲಿ, ವ್ಯಾಪಕ ಮಾನವ ಚಟುವಟಿಕೆಗಳು ಈ ಹಚ್ಚ ಹಸುರಿನ ಕಾಡುಗಳ ಉಳಿವಿಗೆ ಬೆದರಿಕೆಯನ್ನೊಡ್ಡುತ್ತಿವೆ. ಇದರಿಂದಾಗಿ ಇಲ್ಲಿನ ಪ್ರಾಣಿಗಳ ಮತ್ತು ಸಸ್ಯಗಳ ಸಂಖ್ಯೆ ಕ್ಷೀಣಿಸುತ್ತಿದೆ. ಪಶ್ಚಿಮ ಘಟ್ಟದಲ್ಲಿ ಏನೇನು ಬದಲಾವಣೆಗಳು ನಡೆಯುತ್ತಿದೆ ಎಂಬುದನ್ನು ನಿಖರವಾಗಿ ತಿಳಿಯಲು ಸಂಶೋಧಕರು ಮತ್ತು ಸಂರಕ್ಷಕರ ತಂಡವು, 'ಆಕಾಶ ದ್ವೀಪ' ಎಂದು ಕರೆಸಿಕೊಳ್ಳುವ ಪಳನಿ ಬೆಟ್ಟದಲ್ಲಿ, ಈ 40 ವರ್ಷಗಳಲ್ಲಿ ಸಸ್ಯವರ್ಗದ ಹೊದಿಕೆಯಲ್ಲಾದ ಬದಲಾವಣೆಗಳನ್ನು ಅಧ್ಯಯನ ಮಾಡಿದೆ.

‘ಈ ಆಕಾಶ ದ್ವೀಪಗಳು ಆವಾಸಸ್ಥಾನ ದ್ವೀಪಗಳಾಗಿವೆ. ಸಾಮಾನ್ಯವಾಗಿ ಇವು ಹೆಚ್ಚಿನ ಎತ್ತರದ ಆರ್ದ್ರ, ತಂಪಾದ ಆವಾಸ ಸ್ಥಾನಗಳಾಗಿದ್ದು, ಶುಷ್ಕ, ಬೆಚ್ಚಗಿನ ಕಡಿಮೆ ಎತ್ತರದ ಪ್ರದೇಶಗಳಿಂದ ಬೇರ್ಪಡಿಸಿವೆ’ ಎನ್ನುತ್ತಾರೆ ಈ ಅಧ್ಯಯನದ ಸಹಲೇಖಕರಾದ ಡಾ. ವಿ.ವಿ. ರಾಬಿನ್. ಪಶ್ಚಿಮಘಟ್ಟಗಳು, ಅದರಲ್ಲೂ, ವಿಶೇಷವಾಗಿ ಶ್ರೀಲಂಕಾ ಪ್ರದೇಶದಲ್ಲಿರುವ ಆಕಾಶ ದ್ವೀಪವು, ಎತ್ತರ ಪ್ರದೇಶದ ತೇವಾರಣ್ಯವಾದ 'ಶೋಲಾ ಕಾಡುಗಳ' ಮತ್ತು ಗುಡ್ಡಗಾಡಿನ ವಿಶೇಷ ಹುಲ್ಲುಗಾವಲುಗಳ ಸಮ್ಮಿಲನ. ಈ ಹುಲ್ಲುಗಾವಲುಗಳು ಜೀವವೈವಿಧ್ಯದಲ್ಲೂ ಸಮೃದ್ಧವಾಗಿದ್ದು, ಹುಲ್ಲುಗಳ 27 ಸ್ಥಳೀಯ ಪ್ರಭೇದಗಳನ್ನು ಹೊಂದಿವೆ.

'ಅಂತರರಾಷ್ಟ್ರೀಯ ನಿಸರ್ಗ ಸಂರಕ್ಷಣಾ ಒಕ್ಕೂಟ'ವು ಇವುಗಳಲ್ಲಿ ಒಂದನ್ನು ಅಳಿವಿನಂಚಿನ ಪ್ರಭೇದ ಎಂದು ವರ್ಗೀಕರಿಸಿದೆ. ಇಂತಹ ಅನೇಕ ಸಸ್ಯ-ಪ್ರಾಣಿಗಳಿಗೆ ನೆಲೆಯಾಗಿರುವುದಲ್ಲದೇ, ಈ ಹುಲ್ಲುಗಾವಲುಗಳು ತಗ್ಗಿನ ಪ್ರದೇಶಗಳಿಗೆ ನೀರನ್ನೂ ಹರಿಸುತ್ತವೆ.

‘ಪಶ್ಚಿಮ ಘಟ್ಟಗಳು, ಬಹುಶಃ ಭಾರತದಲ್ಲಿನ ಉತ್ತಮ ದಾಖಲಿತ ಭೂದೃಶ್ಯಗಳಾಗಿದ್ದರೂ ಅಲ್ಲಿನ ಕೀಟಗಳು ಮತ್ತು ಇತರ ಕಶೇರುಕಗಳ ಬಗ್ಗೆ ನಮಗೆ ತಿಳಿಯದಿರುವ ಅಂಶಗಳು ಬೇಕಾದಷ್ಟಿವೆ. ಅಲ್ಲಿ ಅನೇಕ ಸ್ಥಳೀಯ ವಿಶಿಷ್ಟ ಹಕ್ಕಿಗಳು ಕೂಡ ಇವೆ’ ಎನ್ನುತ್ತಾರೆ ಈ ಅಧ್ಯಯನದ ಸಹ ಲೇಖಕರಾದ ಡಾ ಮಿಲಿಂದ್ ಬೈಯಾನ್.

ಇಂದು, ಹುಲ್ಲುಗಾವಲುಗಳು ಎಂದರೆ ಅನುಪಯುಕ್ತ ತ್ಯಾಜ್ಯತಾಣಗಳು ಎಂಬ ತಪ್ಪುಗ್ರಹಿಕೆಯ ಕಾರಣದಿಂದ, ಈ ವಿಶಿಷ್ಟ ಆವಾಸಸ್ಥಾನಗಳು ಅಪಾಯಕ್ಕೆ ಸಿಲುಕಿವೆ. 'ಪ್ಲಾಸ್ ಒನ್' (PLOS ONE) ಪತ್ರಿಕೆಯಲ್ಲಿ ಪ್ರಕಟವಾದ ಈ ಅಧ್ಯಯನದ ಪ್ರಕಾರ, 1973ರಿಂದ 2014ರರವರೆಗಿನ 40 ವರ್ಷಗಳ ಅವಧಿಯಲ್ಲಿ, ಪಳನಿ ಬೆಟ್ಟದ ಹುಲ್ಲುಗಾವಲುಗಳು, ಕಾಡುಗಳು, ತೋಟಗಳು ಮತ್ತು ಕೃಷಿಭೂಮಿಗಳ ವಿಸ್ತೀರ್ಣದಲ್ಲಿ ಬಹಳ ಬದಲಾವಣೆ ಆಗಿದೆ ಎಂಬುದನ್ನು ಸಂಶೋಧಕರು ಕಂಡುಕೊಂಡಿದ್ದಾರೆ.

ಸಂಶೋಧಕರು ಈ ಅಧ್ಯಯನಕ್ಕೆ ಆರಿಸಿಕೊಂಡಿದ್ದ 40 ವರ್ಷಗಳ ಅವಧಿಯಲ್ಲಿ ಪ್ರತಿ ದಶಕದ ಮಾಹಿತಿಗಾಗಿ, ಪಳನಿ ಬೆಟ್ಟಗಳ ಭೂದೃಶ್ಯದ ಉಪಗ್ರಹ ಚಿತ್ರಗಳನ್ನು ಬಳಸಿದ್ದಾರೆ. ಅದರ ವೈಶಿಷ್ಟ್ಯಗಳ ಆಧಾರದ ಮೇಲೆ, ಅವರು ಅಲ್ಲಿನ ಭೂಪ್ರದೇಶವನ್ನು ಶೋಲಾ ಅರಣ್ಯ, ಶೋಲಾ ಹುಲ್ಲುಗಾವಲು, ಮರಮುಟ್ಟುಗಳ ತೋಟಗಳು, ಮಾನವ ವಸತಿ, ಕೃಷಿಭೂಮಿ ಮತ್ತು ಜಲಪಾತ್ರೆಗಳಾಗಿ ವರ್ಗೀಕರಿಸಿದರು.

ಈ ಸಂಶೋಧನೆಯಿಂದ ಕಂಡುಬಂದ ಅಚ್ಚರಿದಾಯಕ ಹಾಗೂ ಬೇಸರದ ವಿಚಾರವೆಂದರೆ, ಈ ಭೂಭಾಗದ ಅರ್ಧಕ್ಕಿಂತಲೂ ಹೆಚ್ಚು, (ನಿಖರವಾಗಿ ಹೇಳುವುದಾದರೆ ಶೇಕಡ 58ರಷ್ಟು) ಪ್ರದೇಶವು, 40ವರ್ಷಗಳಲ್ಲಿ ಭಾರಿ ಬದಲಾವಣೆಗೆ ಒಳಗಾಗಿದೆ. ಇದರ ಅರ್ಥ, 249 ಚದರ ಕಿಲೊ ಮೀಟರ್ ಶೋಲಾ ಹುಲ್ಲುಗಾವಲುಗಳು ಮತ್ತು 33 ಚದರ ಕಿಲೊ ಮೀಟರ್ ಶೋಲಾ ಅರಣ್ಯವು ನಷ್ಟವಾಗಿದೆ.

ಹುಲ್ಲುಗಾವಲುಗಳ ಮೇಲೆ ದುಷ್ಪರಿಣಾಮ ಬೀರುವ ಅಂಶಗಳ ಪೈಕಿ, ಮಾನವನಿರ್ಮಿತ ತೋಟಗಳ ಪಾಲು ಹೆಚ್ಚು. ತೋಟಗಳ ಪ್ರಮಾಣವು ಈ 40 ವರ್ಷಗಳಲ್ಲಿ 12 ಪಟ್ಟು ಹೆಚ್ಚಾಗಿದ್ದು, ಇವುಗಳೇ ಸ್ಥಳೀಯ ಆವಾಸಸ್ಥಾನಕ್ಕೆ ಅತ್ಯಂತ ಹಾನಿಕಾರಕವಾಗಿವೆ ಎಂದು ಸಂಶೋಧಕರು ಗಮನಿಸಿದ್ದಾರೆ. ಕೃಷಿ ಭೂಮಿಯ ಪ್ರಮಾಣವು 31.1 ಚದರ ಕಿಲೊ ಮೀ‌‌‌ಟರ್‌ನಿಂದ 104.5 ಚದರ ಕಿಲೊ ಮೀಟರ್‌ಗೆ ಹೆಚ್ಚಳ ಆಗಿರುವುದೂ, ಇದೇ ಕಾಲಘಟ್ಟದಲ್ಲಿ. 1993– 2014ರ ಅವಧಿಯಲ್ಲಿ ತೋಟ ಮತ್ತು ಕೃಷಿಯ ಹೆಚ್ಚಳವು ಅತ್ಯಧಿಕ ಪ್ರಮಾಣದಲ್ಲಿ ಕಂಡುಬಂದಿದ್ದು, ಈ ಸಮಯದಲ್ಲೇ ಸ್ಥಳೀಯ ಸಸ್ಯವರ್ಗದಲ್ಲಿ ಗರಿಷ್ಠ ಬದಲಾವಣೆ ಕಂಡುಬಂದಿದೆ ಎಂದು ಸಂಶೋಧಕರು ಗಮನಿಸಿದ್ದಾರೆ.'

ಈ ಹುಲ್ಲುಗಾವಲು ಆವಾಸಸ್ಥಾನದಲ್ಲಾದ ಇಂತಹ ಒಂದು ವ್ಯಾಪಕ ಬದಲಾವಣೆಯು, ಶೋಲಾ ಕಾಡುಗಳ ಜೀವವೈವಿಧ್ಯದ ಮೇಲೆ ಭರಿಸಲಾಗದ ಪರಿಣಾಮಗಳನ್ನು ಉಂಟುಮಾಡಿದೆ.

‘ಈ ಭೂಪ್ರದೇಶದಲ್ಲಿ ಮಾತ್ರ ಕಂಡುಬರುತ್ತಿದ್ದ ವಿಶಿಷ್ಟ ಹಕ್ಕಿಗಳಲ್ಲಿ ಒಂದಾದ 'ನೀಲಗಿರಿ ಪಿಪಿಟ್', ತನ್ನ ಆವಾಸಸ್ಥಾನದ ಮೇಲಾಗುತ್ತಿರುವ ದೌರ್ಜನ್ಯದ ಕಾರಣದಿಂದ ಸ್ಥಳೀಯವಾಗಿ ಅಳಿವಿನಂಚಿಗೆ ಸರಿಯುತ್ತಿರುವುದು ಕಂಡುಬಂದಿದೆ. ಈ ಪಕ್ಷಿಗಳಂತೆಯೇ, ಅನೇಕ ಸಸ್ಯಗಳು, ಕೀಟಗಳು ಮತ್ತು ಇತರ ಪ್ರಭೇದಗಳ ಮೇಲೂ ಈ ಬದಲಾವಣೆ ಪ್ರಭಾವ ಬೀರುತ್ತದೆ ಎಂದೂ ನಾವು ಅರ್ಥೈಸಿಕೊಳ್ಳಬಹುದು’ ಎನ್ನುತ್ತಾರೆ ಡಾ. ಬೈಯಾನ್.

ಅಧ್ಯಯನವು, ಪಶ್ಚಿಮಘಟ್ಟಗಳು ಎದುರಿಸುತ್ತಿರುವ ಸಮಸ್ಯೆಗಳ ಬಗ್ಗೆ ನಮ್ಮನ್ನು ಎಚ್ಚರಿಸುವ ಮೊದಲ ಅಧ್ಯಯನವೇನಲ್ಲ. ಆದರೆ, ಪಶ್ಚಿಮಘಟ್ಟದ ಹುಲ್ಲುಗಾವಲಿನ ಭವಿಷ್ಯವನ್ನು ವಿವರವಾಗಿ ವಿವರಿಸುವ ಮೊದಲನೆಯ ಸಂಶೋಧನೆ ಇದಾಗಿದೆ. ಆವಾಸಸ್ಥಾನಗಳ ವೈವಿಧ್ಯವನ್ನು ಕಡೆಗಣಿಸಿ ಎಲ್ಲವನ್ನೂ ಒಂದೇ ರೀತಿ ನೋಡುವುದು, ಹೇಗೆ ತಪ್ಪು ಅರ್ಥೈಸುವಿಕೆಗೆ ಕಾರಣವಾಗಬಹುದು ಎಂಬುದರ ಬಗ್ಗೆಯೂ ಈ ಸಂಶೋಧನೆ ಗಮನ ಸೆಳೆಯುತ್ತದೆ.

ಹಾಗಾದರೆ, ನಾವು ಈ ಹಾನಿಯನ್ನು ಹೇಗೆ ತಡೆಯಬಹುದು? ಈ ಪ್ರಶ್ನೆಗೆ ಉತ್ತರವಾಗಿ, ಸಂಶೋಧಕರು, ಈ ವಿಶಿಷ್ಟ ಆವಾಸಸ್ಥಾನವನ್ನು ಪುನಃಸ್ಥಾಪಿಸಲು ಮತ್ತು ರಕ್ಷಿಸಲು, ಅರಣ್ಯ ಅಧಿಕಾರಿಗಳು ಮತ್ತು ಸ್ಥಳೀಯರಂತಹ ವಿವಿಧ ಪಾಲುದಾರರನ್ನು ಒಳಗೊಂಡಿರುವ ಪುನಃಸ್ಥಾಪನಾ ಮಾದರಿಯನ್ನು ಶಿಫಾರಸು ಮಾಡುತ್ತಾರೆ.

‘ಅಳಿದುಳಿದ ಹುಲ್ಲುಗಾವಲುಗಳನ್ನು ಸಂರಕ್ಷಿಸಿ, ಜೊತೆಗೇ, ಅವುಗಳೊಳಗೆ ಹೊಸ ತೋಟಗಳ ಆಕ್ರಮಣವನ್ನು ತಡೆಗಟ್ಟುವ ಮೂಲಕ ಮಾತ್ರ, ಈಗಿರುವ ಹುಲ್ಲುಗಾವಲು ಆವಾಸಸ್ಥಾನಗಳ ಸಂರಕ್ಷಣೆ ಸಾಧ್ಯ’ ಎಂಬುದು ಅವರ ಸ್ಪಷ್ಟ ಅಭಿಪ್ರಾಯ.

Section: General, Science, Ecology, Society, Policy, Deep-dive Source:
Kanpur Friday, 23 March, 2018 - 15:19

In a new study, researchers have developed a low-cost and eco-friendly method to extract gold from electronic waste using the leaves of the plant Lagerstroemia speciosa, commonly called the Pride of India. They have applied the principle of biosorption—the ability of biological materials in an aqueous solution to bind with heavy metals—to extract gold from wastewater. The findings of the study, published in the journal Separation and Purification Technology, show that nearly 100% of the gold can be extracted from e-waste that includes circuit boards of mobile phones, laptops, cameras and other electronic appliances.

Gold is used in the manufacture of electronic circuit boards due to its high electric conductivity and inert nature. In fact, printed circuit boards have a higher concentration of gold than naturally occurring ores! In 2016, an estimated 44.7 million tonnes of e-waste was generated in the world. With the numbers only increasing every year, the race is on for finding effective ways to extract this wealth from waste to meet the ever-increasing demand for gold.

In this study, researchers from the North Maharashtra University, the Indian Institute of Technology Kanpur and the Directorate of Geology and Mining, Government of Maharashtra, suggest using biosorption as an eco-friendly alternative to the conventional methods. In traditional methods such as precipitation and ion exchange, many toxic chemicals are used and produced, which harm the environment. Biosorption, on the other hand, is not only eco-friendly but also economical.

The researchers used powdered leaves of Lagerstroemia speciosa, a deciduous tree native to Southern Asia and widely cultivated for its ornamental value. They enhanced the adsorption capacities of the powdered leaves by modifying their chemical structure with Polyethylenimine (PEI)—a cationic polymer which has many applications in adsorption and extraction of metals. This process “improves the mechanical strength of the biosorbent (the powdered leaves) and augment the adsorption potential”, say the authors. It is because PEI prevents the leaching of organic matter, leaves in this case.

The researchers tested the improved powdered leaves on e-waste and jewellery-washed wastewater. E-wastes, such as printed circuit boards, were treated with nitric acid and aqua regia solutions to remove the base metals and prepare the gold-bearing acid-leached solutions. The powdered Lagerstroemia speciosa leaves were then used to separate gold from the solution. They found that the powdered leaves have high gold absorption and adsorption capacity, and recovered more than 95% gold from the acidic solution on which it was tested.

So how does the leaf help in recovering gold? The researchers studied the adsorption-reduction mechanism using X-rays to figure this out. They found that the positively charged molecules of the PEI-modified powdered leaves are at first attracted to the negatively charged gold complex (AuCl4) present in the solution. It then undergoes reduction to give pure gold, which can then be separated from the surface of the powdered leaves using acid thiourea. The separation process also enables the biosorbent to be reused for several cycles of gold recovery.

“It is likely that the amino group from PEI forms complexes with gold ions and subsequently reduces these to zero-valent gold. This adsorption-reduction mechanism reduces gold ions to zero-valent gold on PEI-LS surface”, say the researchers, talking about the chemical reaction that enables gold recovery. They also conducted various experiments to understand how different parameters affect the efficiency of gold recovery.

This study explores a quick, near complete gold recovery from waste using leaves of a native plant species—an approach that could be a potential answer to the management of e-waste in the country.
 

Section: General, Science, Technology, News Source: Link
Kodaikanal Friday, 23 March, 2018 - 07:29

The Western Ghats is a scenic holiday retreat for many. But, there is more to it. Being one of the eight ‘world’s hottest hotspots of biodiversity’, the natural ecosystem including forests and grasslands, hosts an incredible number of plants and animal species and play a major role in maintaining the Indian monsoon. However, in the recent years, extensive human activities are threatening the survival of these lush green forests, and animal and plant numbers are dwindling. So what exactly is happening? To know this, a team of researchers and conservationists have studied the changes in the cover of vegetation for forty years in the Palani Hills, a ‘sky island’ in the Western Ghats.

“Sky Islands are habitat islands - usually high elevation wet, cool habitats isolated by dry, warm low elevation areas”, says Dr. V.V.Robin, and an author of the study. In the Western Ghats-Sri Lanka region, a ‘sky island’ refers to the unique mosaic of Shola forests and montane grasslands. The grasslands are also rich in biodiversity and have 27 endemic species of grasses; one of them classified as ‘near threatened’ by the International Union for Conservation of Nature (IUCN). Apart from being home to many animals, the grasslands channel water to low lying areas.

“Although the Western Ghats are perhaps some of the better-documented landscapes in India, we still know little about insects and other vertebrates from this landscape. And we know that there are endemic birds in the landscape”, says Dr. Milind Buyan, another author of the study. Today, flawed perceptions of these grasslands as ‘wastelands’ have put these unique habitats under threat. In this study, published in the journal PLOS ONE, the researchers have explored how, over a 40 year period, from 1973 – 2014, the grasslands, forests, plantations and agriculture lands have changed over space and time in Palani Hills, which range from Kerala to Tamil Nadu.

The researchers have used satellite images of the Palani Hills landscape of each decade of the study period. Based on its features, they classified the landscape into Shola forest, Shola grassland, timber plantations, human settlements, agriculture and water bodies. They found that more than half of the landscape, 58% to be exact, had undergone a massive change over the 40-year period. It translates into a loss of 249 km2 of Shola grasslands and 33km2 loss of the forest cover.

Among factors affecting the grasslands, the researchers point out that plantations, which had undergone a 12-fold increase in the 40 years span, were the most detrimental to the native habitat. Land under agriculture, which increased from 31.1 km2 to 104.5 km2 in the same interval, came second. They observed that the maximum change in the native vegetation occurred during 1993- 2014 when the increase in plantation and agriculture was seen to be the highest.

Such an extensive change in the grassland habitats has left irreplaceable effects on the biodiversity of the Shola forests. “We know that there are endemic birds in the landscape - one of the threatened endemic birds, Nilgiri Pipit is restricted only to these montane grasslands, and their habitats are reducing, and may even face local extinction. We can only imagine that if this is the case with birds, that many plants, insects and other taxa are also impacted”, explained Dr. Bunyan.  

Though this is not the first study to warn us of the threats the Western Ghats face, this is the first to explore in detail the fate of grasslands. It also draws attention to the how the generalisation of habitat types can lead to misrepresentation. So, how do we stop the damage? The researchers recommend a nuanced restoration model that involves various stakeholders like forest officials and locals, to restore and protect this unique habitat. “Conserving the remaining grasslands and preventing the advances of newer plantations into the grasslands in the landscape is the best chance to preserve and secure the future grasslands,” they say. 

Section: General, Science, Ecology, Society, Policy, Deep-dive Source:
Kharagpur Thursday, 22 March, 2018 - 08:33

Power cuts in many parts of the country are so commonplace that we have learnt to accept and adapt to the erratic supply, no matter how frustrating. With summer rearing its fiery head, the threat of sitting in sweltering heat without fans or air-conditioners is a nightmare. A recent UN report found that 10% of people from developing countries have no access to electricity! Now, a study by researchers from the Indian Institute of Technology, Kharagpur, has found a way to potentially generate power in our backyard. All you need is a pond, algae, and a microbial fuel cell!

There is a recent interest in the development of fuel cells powered by microorganisms which help in the generation of electricity through chemical reactions. These fuel cells have two terminals -- a positive terminal called the anode, and a negative terminal called cathode. Chemical reactions at either or both of the terminals cause the electrons to flow across these terminals, thus generating electricity.

Sewage water from our houses is rich in organic compounds and thus helps the growth of algae and other microbes. A sewage treatment plant typically has a large oxidation pond where the water is treated using the combined activity of algae, bacteria and sunlight. The researchers propose to harness this chemical reaction to power our electricity grids.

The researchers have compared two types of microbial fuel cells -- one called a sediment microbial fuel cell (SMFC) where the anode is buried in the sediments of a waterbody (pond) and the cathode is suspended in the surface water, and the other which is a modified SMFC – a sediment microbial carbon-capture (SMCC) – which sought to improve performance by employing algae in the water above the sediment layer at the cathode. They analysed the power generation capacity, dissolved oxygen variations, sediment organic matter removal and algal growth of both the SMFC and the SMCC operating under similar conditions.

The results showed that the performance of SMCC was higher than SMFC, with the added advantage that SMCC can be deployed in wastewater treatment plants that has algae. The SMCC not only generated more power but also removed sediment organic matter and nitrogen more efficiently. It also helped in carbon conversion and in increasing the growth of algae in the water. Also, the researchers found that the device does not require external aeration, and it acquired the necessary oxygen from the algae and water. It also did not need a membrane between the electrodes like other microbial fuel cells.

Thanks to studies like this, wastewater from our homes may help power up an entire village or town while rendering the water reusable at the same time!

Section: General, Science, Technology, News Source: Link
Bengaluru Thursday, 22 March, 2018 - 07:40
Section: General, Science, Ecology, Health, Society, Policy, Infographics Source:
Bengaluru Wednesday, 21 March, 2018 - 12:57

In a new study, researchers from the Indian Institute of Science, have found that ten confined water molecules play a significant role in keeping the insulin molecules together. In their findings published in the Journal of Physical Chemistry, the researchers have used computer models to study how water molecules help in stabilising the structure of insulin for storage in our body.

Insulin is a hormone produced by the islet cells of our pancreas. The hormone helps our body use the carbohydrates that we eat. Thanks to the high incidence of diabetes in the world, scientists across the globe are trying to understand the mechanism of insulin production, storage and its role in our well-being. This study adds a new body of information to what we know about insulin so far.

Under an electron microscope, insulin is a monomer—a molecule that can combine with others of the same kind to form long chains of ‘polymers’. However, in the pancreas, it is stored in groups of six (hexamer), arranged around two positively-charged zinc ions (cations). In this study, the researchers used X-ray crystallography to find that on an average, ten water molecules are present in the cavity of the hexamer.

But what do these ten water molecules do? Using computer simulations of the insulin hexamer structure, zinc cations and water molecules, the researchers found that three of the ten water molecules and three histidine residues—the residue left behind after the synthesis of the amino acid called histidine—coordinate with each of the zinc cations and form an eight-faced structure. The rest of the water molecules enter and leave the cavity, but the simulation showed that these molecules stay fixed nearly in place while inside the hexamer.

The study identified that about 15 hydrogen bonds formed between the ten water molecules in the cavity, and peptide bonds with the histidine residues. The researchers claim that the water molecules act as a ‘backbone’ in the hexamer structure, keeping it intact, since when the water molecules were removed, the structure of the hexamer fell apart within picoseconds!

The researchers say that this understanding of the role of water molecules in the structure of insulin could explain how the hexamer, stored in the pancreas, breaks into single insulin molecules when the body needs insulin for metabolism. Also, the study may also help pharmaceutical companies in solving the challenge of ‘insulin aggregation’, which renders insulin useless.

 

Section: General, Science, Technology, News Source: Link
Mumbai Wednesday, 21 March, 2018 - 08:23

Indian consumers are willing to pay more for air conditioners with higher energy efficiency, says research from IIT Bombay.

Energy efficient devices contribute significantly towards a greener environment and help tackle climate change. In 2006, the Government of India initiated the program of ‘star labels’ on appliances that provide information regarding their energy efficiency. Initially voluntary and covering few appliances, star label is now mandatory in India for few appliances like the room air conditioners and frost-free refrigerators. While regulations and innovation are crucial to design such devices, consumer choice also plays a significant role. How influential are the rating labels in driving customer choices? To answer this, researchers from the Indian Institute of Technology Bombay (IIT Bombay) have conducted a study and found out that on an average, consumers prefer air conditioners that have labels, and are willing to pay more for those that are energy efficient.

As per a report from the Ministry of Statistics and Program Implementation, households in India consume about 22% of electricity. Air conditioners, one of the most energy-intensive appliances, is increasingly becoming common and could impact electricity consumption in a big way. Investing in an energy efficient air conditioner can reduce the demand for electricity and be pocket-friendly too. It is believed that informing customers about how much energy a device consumes could push them to towards choosing energy efficient ones. Star labels, ranging from one star (least energy efficient) to five stars (most energy efficient), help customers compare different products and make an informed choice.

In this study, researchers from the Centre for Technology Alternatives for Rural Areas and Interdisciplinary Program in Climate Studies, IIT Bombay, led by Prof. Anand B Rao, used statistical tools to analyse what consumers preferred while choosing a 1.5-ton split air conditioner. The researchers analysed 1184 observations from 148 individuals, as each respondent gave 8 different preferences in hypothetical purchase situations. They estimated consumer preference for different attributes of ACs such as brand, air filter, noise level and star rating.

The study also found that 70% of the people surveyed were aware of star labels and 48% believed that higher star rated devices consume lesser electricity. Though customer preference varied with star rating levels, it was seen that 69% preferred an air conditioner rated 3-star over one with a 2-star rating, and 78% preferred a 5-star rated air conditioner over a 2-star rated one. In addition, 85% of the respondents preferred the presence of a star label on the ACs.

Using statistical models, the study found that customers were willing to pay up to ₹12,500 more for air conditioners with star labels -- an amount significantly higher than what they would pay for the presence of a brand name (₹9,000). In addition, 62% of the consumers were willing to pay for the increment in star rating level from 3 to 5. The study concluded that such investment would be economically beneficial if the household monthly consumption of electricity is greater than 100 kWh, as the savings would be greater than the estimated cost incurred for more efficiency.

“This study provides empirical support for the standards and labelling program on air conditioners.  In India, the impact of the labelling program on consumer choices has been understood only qualitatively. This study provides quantitative estimates of the impact on the program on consumer choices”, says Dr Manisha Jain, an author of the study, talking about how the results could be used to design programs that drive energy efficiency.

The study demonstrates that the consumer information programs as mandated by the regulations have been bearing fruits through a wider recognition among the Indian consumers. “This shows that due to the standards and labelling program, the adoption of energy efficient ACs is market-driven and may not require any further government intervention apart from strengthening the standards”, say the authors. Extending this study further, the researchers plan to explore the relationship of rating preferences with household income, education, and other attributes to help design targeted programs for increasing energy efficiency.

Section: General, Science, Technology, Society, Deep-dive Source:
Delhi Tuesday, 20 March, 2018 - 14:27

The Biotechnology Industry Research Assistance Council (BIRAC) celebrated its 6th Foundation Day on Tuesday, March 20th, at the India Habitat centre in New Delhi. This year, the theme for the Foundation Day celebration was ‘Sustaining Innovation: A market driven pathway’. The event saw a participation from large number of dignitaries from the industry and academia, public and private sector, policy makers and national and international organizations.

The Foundation Day celebration was inaugurated by the Hon’ble Minister of Science & Technology and Earth Sciences, Environment, Forest & Climate Change, Dr. Harsh Vardhan. In his address, the honourable minister mentioned about the need for a collaborative approach for identifying and solving the problems of the nation.

Prof Vinod K Paul, Hon'ble Member (Health) NITI Aayog, Govt. of India, was the guest of honour of the event. He provided many recommendations to the august audience, including the need of more focus in primary healthcare sector.

In his opening remarks, Prof Ashutosh Sharma, Secretary, DST & DBT and Chairman, BIRAC appreciated the tremendous contribution of BIRAC to the nation. He mentioned that BIRAC is a unique organisation which supports innovation in both public and private sector.

“BIRAC has over the years facilitated the creation of vibrant start up ecosystem. We are pleased that we are seeing the impact of this ecosystem in not only providing affordable solutions for societal problems but also enhancing innovation competence. It is now important to develop robust pathways to sustain these innovations”, said Dr Renu Swarup, Senior Advisor, DBT & Managing Director, BIRAC.

Prof. G Padmanabhan, former Director and current Honorary Professor of the Indian Institute of Science, Bengaluru, was felicitated in the event. The second volume of his memoir titled “Doing science in India: My second innings” was also released. Names of the preliminary winners of the SoCH (Solutions for Community Health) award were also announced. This award is an innovation challenge award under two themes, ‘platform technologies for reducing disease burden’ and ‘sanitation and waste recycling’.

“The foundation day plenary talks and panel discussions are aimed at building momentum for health and development initiatives via innovations and foster scientific collaboration among national and international groups. The focus of this event is on sustaining and survival of start ups in the market after their launch”, mentioned the press release from BIRAC.

BIRAC is non-profit public-sector enterprise set up by the Department of Biotechnology (DBT), Ministry of Science and Technology to promote emerging biotech industry and to undertake strategic research and innovation. Through various schemes and collaborations, BIRAC is promoting novel, high quality affordable technologies. BIRAC has over 10 flagship schemes supported by DBT and manages 7 programs collaboratively funded with international partners. In the last six years, BIRAC has supported over 650 projects, and more than 500 start ups and entrepreneurs. It has also developed a strong support network across the country through its 30 supported incubators and 2 regional centres for entrepreneurship. Over 100 products and technologies have been developed through BIRAC support and 150 Intellectual Property Rights have been generated so far.

Section: General, Science, Technology, Society, News, Events Source:

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