Knowledge Update

​New York, Oct 8 (IANS) Some fungicides, often regarded as safe for bees, could be a major contributor to honey bee colony losses, and the number of different pesticides within a colony -- regardless of dose -- closely correlates with colony deaths, suggests new research.

"Our results fly in the face of one of the basic tenets of toxicology: that the dose makes the poison," said senior author of the study Dennis van Engelsdorp, Assistant Professor at the University of Maryland in the US.

"We found that the number of different compounds was highly predictive of colony deaths, which suggests that the addition of more compounds somehow overwhelms the bees' ability to detoxify themselves," van Engelsdorp noted.

The researchers followed 91 honey bee colonies in the US, owned by three different migratory commercial beekeepers, for an entire agricultural season. 

The colonies began their journey in Florida and moved up the East Coast, providing pollination services for different crops along the way. 

A total of 93 different pesticide compounds found their way into the colonies over the course of the season, accumulating in the wax, in processed pollen known as bee bread and in the bodies of nurse bees. 

The study, published online in the journal Scientific Reports, showed that colonies with very low pesticide contamination in the wax experienced no queen events or colony death, while all colonies with high pesticide contamination in the wax lost a queen during the beekeeping season.

The study results also suggest that some fungicides, which have led to the mortality of honey bee larvae in lab studies, could have toxic effects on colony survival in the field. 

In the current study, pesticides with a particular mode of action also corresponded to higher colony mortality. 

For example, the fungicides most closely linked to queen deaths and colony mortality disrupted sterols -- compounds that are essential for fungal development and survival.

"We were surprised to find such an abundance of fungicides inside the hives, but it was even more surprising to find that fungicides are linked to imminent colony mortality," lead author on the study Kirsten Traynor from the University of Maryland said.

"These compounds have long been thought to be safe for bees," Traynor noted

​Washington, Oct 7 (IANS) Globally, life expectancy increased from about 62 years to nearly 72 from 1980 to 2015, thanks to improvements in sanitation, immunisations, indoor air quality and nutrition in poor countries, and several nations in sub-Saharan Africa rebounding from high death rates due to HIV/AIDS, says a new report.

However, such progress is threatened by increasing numbers of people suffering serious health challenges related to obesity, high blood sugar, and alcohol and drug abuse, said the Global Burden of Disease 2015 study published in The Lancet.

The study analysed 249 causes of death, 315 diseases and injuries, and 79 risk factors in 195 countries and territories between 1990 and 2015. 

The progress in India, however, has not been very impressive, according to the report.

All countries in the South Asian region did much worse than expected at reducing deaths in children under five, with India recording the largest number of under-five deaths of any country in 2015, at 1.3 million.

Globally, 5.8 million children under age five died in 2015, representing a 52 per cent decline in the number of under-five deaths since 1990. 

"Over the past 25 years, there have been important and impressive gains in the number of children surviving past their fifth birthdays, a significant milestone," said one of the study authors Haidong Wang, Associate Professor at Institute for Health Metrics and Evaluation (IHME) at the University of Washington in Seattle.

"Regrettably, many nations -- especially those low on the Socio-demographic Index -- have not made such gains and need to hasten the pace of progress, including availability of cost-effective vaccines, expanded access to clean water, and other interventions," Wang noted.

The study draws on the work of more than 1,800 collaborators in over 120 countries.

Bangladesh has improved maternal survival much faster than expected, while India and Nepal fared poorly.

Most countries in the South Asian region -- including India and Pakistan -- did better than expected at reducing health loss from stroke and lower respiratory infections. India also performed much worse than expected on tuberculosis, the report said.

The number of maternal deaths globally dropped by roughly 29 per cent since 1990, and the ratio of maternal deaths fell 30 per cent, from 282 per 100,000 live births in 1990 to 196 in 2015.

Between 2005 and 2015, death rates from HIV/AIDS decreased 42 per cent, malaria 43 per cent, preterm birth complications 30 per cent, and maternal disorders 29 per cent, according to the study.

Washington, Oct 7 (IANS) A research team led by US Department of Energy's Lawrence Berkeley National Laboratory has created the world's smallest transistor with a working one-nanometre gate.

In a study published in the journal Science, the researchers described the novel transistor made with a new combination of materials that is even smaller than the smallest possible silicon-based transistor.

"We made the smallest transistor reported to date," said lead researcher Ali Javey from Lawrence Berkeley National Laboratory.

Instead of using silicon, the researchers built their prototype device with a class of semiconductor materials called transition metal dichalcogenides, or TMDs. 

Specifically, their experimental device structure used molybdenum disulfide for the channel material and a single-walled carbon nanotube for the gate.

"Silicon transistors are approaching their size limit," said one of the study authors, Moon Kim, Professor at The University of Texas at Dallas.

"Our research provides new insight into the feasibility to go beyond the ultimate scaling limit of silicon-based transistor technology," Kim explained.

As current flows through a transistor, the stream of electrons travels through a channel, like tap water flowing through a faucet out into a sink. 

A "gate" in the transistor controls the flow of electrons, shutting the flow off and on in a fraction of second.

"As of today, the best/smallest silicon transistor devices commercially available have a gate length larger than 10 nanometres," Kim said.

"The theoretical lower limit for silicon transistors is about five nanometres. The device we demonstrate in this article has a gate size of one nanometre, about one order of magnitude smaller," he added.

"It should be possible to reduce the size of a computer chip significantly utilising this configuration," Kim noted.

One of the challenges in designing such small transistors is that electrons can randomly tunnel through a gate when the current is supposed to be shut off. Reducing this current leakage is a priority.

"The device we demonstrated shows more than two orders of magnitude reduction in leakage current compared to its silicon counterpart, which results in reduced power consumption," Kim said. 

"What this means, for example, is that a cellphone with this technology built in would not have to be recharged as often," he explained.

​San Francisco, Oct 5 (IANS) US technology company Avaya on Wednesday announced "Cloud Networking Platform", a complete network lifecycle management solution for enterprise and mid-size businesses.

​New York, Oct 6 (IANS) Researchers at Massachusetts Institute of Technology (MIT) have developed a new method for 3-D printing soft materials that make robots safer and more precise in their movements.

​Washington, Oct 7 (IANS) Citing the example of the proposed pan-India Goods and Services Tax (GST), the IMF on Friday said the country has shown that progress on reforms could attract investment and boost prospects of India's medium-term growth.

​Seoul, Oct 7 (IANS) With the aim to bolster its virtual personal assistants to deliver an Artificial Intelligence (AI)-based ecosystem across its devices and services, Samsung Electronics has acquired Viv Labs, an AI start-up.

​New Delhi, Oct 7 (IANS) The BRICS Business Council is looking into low trade volume among the five emerging economies, while recent agreements in areas like customs coopration are attempts to lower trade barriers among member-nations, the Indian government said on Friday.

New York, Oct 6 (IANS) Apple has reportedly bid goodbye to its third-gen Apple TV, shifting its focus on the new fourth-gen model, media reported on Thursday. According to 9to5mac.com, in an email sent out to employees and education partners, Apple said that it is discontinuing the device. "The third-gen model was introduced in 2012 and was quietly updated a year later. Since then, Apple has shifted its focus to the tvOS-powered fourth-gen Apple TV," the report said. Apple, however, said it will fulfill order backlog for the device. The company is currently selling refurbished models of third-gen Apple TV for $59. Once the refurbished models disappear, "Apple will seemingly have stopped sales of the third-gen Apple TV all together," the report added. It is also not clear if third-gen Apple TV will receive any additional software updates. According to Apple website, every Apple TV comes with complimentary telephone technical support within 90 days of its purchase. In addition, Apple TV and all accessories are covered against defects for one year from the original purchase date by a limited hardware warranty.