Dual-color lasers could lead to cheap and efficient LED lighting

May 2, 2013 ? A new semiconductor device capable of emitting two distinct colours has been created by a group of researchers in the US, potentially opening up the possibility of using light emitting diodes (LEDs) universally for cheap and efficient lighting.

The proof-of-concept device, which has been presented today, 3 May, in IOP Publishing's journal Semiconductor Science and Technology, takes advantage of the latest nano-scale materials and processes to emit green and red light separated by a wavelength of 97 nanometres -- a significantly larger bandwidth than a traditional semiconductor.

Furthermore, the device is much more energy efficient than traditional LEDs as the colours are emitted as lasers, meaning they emit a very sharp and specific spectral line -- narrower than a fraction of a nanometre -- compared to LEDs which emit colours in a broad bandwidth.

One of the main properties of semiconductors is that they emit light in a certain wavelength range, which has resulted in their widespread use in LEDs. The wavelength range in which a given semiconductor can emit light -- also known as its bandwidth -- is typically limited in the range of just tens of nanometres. For many applications such as lighting and illumination, the wavelength range needs to be over the entire visible spectrum and thus have a bandwidth of 300 nm.

Single semiconductor devices cannot emit across the entire visible spectrum and therefore need to be 'put' together to form a collection that can cover the entire range. This is very expensive and is, to a large extent, the reason why semiconductor LEDs are not yet used universally for lighting..

In this study, the researchers, from Arizona State University, used a process known as chemical vapour deposition to create a 41 micrometer-long nanosheet made from Cadmium Sulphide and Cadmium Selenide powders, using silicon as a substrate.

Lead author of the study, Professor Cun-Zheng Ning, said: "Semiconductors are traditionally 'grown' together layer-by- layer, on an atom-scale, using the so-called epitaxial growth of crystals. Since different semiconductor crystals typically have different lattice constants, layer-by-layer growth of different semiconductors will cause defects, stress, and ultimately bad crystals, killing light emission properties."

It is because of this that current LEDs cannot have different semiconductors within them to generate red, green and blue colours for lighting.

However, recent developments in the field of nanotechnology mean that structures such as nanowires, nanobelts and nanosheets can be grown to tolerate much larger mismatches of lattice structures, and thus allow very different semiconductors to grow together without too many defects.

"Multi-colour light emission from a single nanowire or nanobelt has been realized in the past but what is important in our paper is that we realized lasers at two distinct colours. To physically 'put' together several lasers of different colors is too costly to be useful and thus our proof-of concept experiment becomes interesting and potentially important technologically.

"In addition to being used for solid state lighting and full color displays, such technology can also be used as light sources for fluorescence bio and chemical detection," continued Professor Ning.

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Source: http://feeds.sciencedaily.com/~r/sciencedaily/matter_energy/technology/~3/o6clZMs5-78/130502225852.htm

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Health and Fitness: Get the Katherine Jenkins look - Wharf

The Wharf's fitness columnist Laura Williams looks at how running is Katherine Jenkins' motivation for keeping fit and tells how you can do the same.

The singer has just completed the London Marathon and finds running a convenient sport.

How she does it: ''I'm not naturally a person that wants to exercise, but I find running is something I can do wherever I am in the world," said the 32-year-old singer.

Do it for yourself: These are my top tips for anyone tempted to hit the tarmac after last month's race:

? Be confident. Banish fears that you look silly, don't have the right kit and so on.

Remember that you're doing this to enhance your life so shelve those fears just for once.

? Train with someone who already has the bug. That could be your office running crew or a sporty partner or family member.

They can help you establish a routine and you won't feel like the new kid on the exercise block.

? Stick to your plan. When the body says no but the mind says go, go. Your body will catch up eventually.

? Set a deadline. If the marathon inspired you to take up running, start now - it really is the best time of year to put your best foot forward.

It's warm but not too warm and longer, lighter evenings make running later in the day that bit easier.

? Exercise first thing. When you've just had a tough day at work, it can be hard to add another tough hour onto an already tiring day. If you exercise first thing you will get it out of the way, and be energised.

laurawilliamsonline.co.uk

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Source: http://www.wharf.co.uk/2013/05/fitness-get-the-katherine-jenk.html

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Drought across the West spurs resurgence of faith

BERNALILLO, N.M. (AP) ? Along the irrigation canal that cuts through this centuries-old New Mexico town, a small group of churchgoers gathers to recite the rosary before tossing rose petals into the water.

Remnants of a tradition that stretches back to the days of Spanish explorers, the humble offerings are aimed at blessing this year's meager irrigation season and easing a relentless drought that continues to march across New Mexico and much of the western half of the U.S.

From the heart of New Mexico to West Texas and Oklahoma, the pressures of drought have resulted in a resurgence of faith ? from Christian preachers and Catholic priests encouraging prayer processions to American Indian tribes using their closely guarded traditions in an effort to coax Mother Nature to deliver some much needed rain.

On Sunday, congregations across eastern New Mexico and West Texas are planning a day of prayer for moisture and rain.

"We're worried, but we're maintaining our traditional ways and cultural ways. Together we pray, and individually we pray," said Peter Pino, administrator of Zia Pueblo. "We haven't lost hope in the spiritual world, that they'll be able to provide us resources throughout the year.

"We're not giving up. That's pretty much all we can do at this point."

In its wake, the drought has left farmland idle, herds of cattle have been decimated, the threat of wildfire has intensified and cities are thinking twice about the sustainability of their water supplies.

In New Mexico, the renewed interest in the divine and the tension with Mother Nature stems from nearly three years of hot, dry weather. There is no place in the country right now that has it worse than New Mexico. The latest federal drought map shows conditions are extreme or worse across nearly 82 percent of the state. There are spots that have fallen behind in rainfall by as much as 24 inches, causing rivers to run dry and reservoirs to dip to record low levels.

In neighboring Texas and Oklahoma, the story is no different.

The faithful gathered Wednesday night in Oklahoma City to recite a collection of Christian, Muslim and Jewish prayers for the year's first worship service dedicated to rain.

The Catholic bishop in Lubbock is planning a special Mass at a local farm in two weeks so that farmers can have their seeds and soil blessed. The archbishop of New Mexico's largest diocese has turned to the Internet and social media to urge parishioners to pray.

The prayer is simple: "Look to our dry hills and fields, dear God, and bless them with the living blessing of soft rain. Then the land will rejoice and rivers will sing your praises, and the hearts of all will be made glad. Amen."

In Bernalillo, the parishioners from Our Lady of Sorrows church recited the rosary as they walked a few blocks from the church to the irrigation canal on a recent Friday evening. At the front of the procession, two men carried an effigy of San Isidro, the patron saint of farmers.

"I think people need to pray for rain," said Orlando Lucero, a school teacher and county commissioner who organized the procession. "We used to do it in every community and in every parish. It was a beautiful tradition that disappeared. Now I'm hoping that we can get other parishes involved."

In Clovis, hospital administrator and active church member Hoyt Skabelund hopes thousands join Sunday's prayer day.

"I don't know that moisture comes because we pray," he said. "You're going to have ebbs and flows and not all rainfall is because someone prayed and not all droughts are because someone didn't pray. But I do believe that prayers are answered and faith in God and a higher power unlocks the powers of heaven."

After all, praying can't hurt, he said.

The simple act of digging a new post hole in eastern New Mexico tells the story of how dry it is. Moist dirt used to turn up several inches below the surface. Now, Skabelund said, someone can dig several feet and not run into any moisture.

In dry times, it's natural for farmers and others who depend on the land to turn to God, said Laura Lincoln, executive director of the Texas Conference of Churches. Still, she and others said praying doesn't take away the responsibility of people to do what they can to ease the effects of drought.

Church leaders are urging their parishioners to conserve water and use better land-management practices like rotating crops.

"We have to play our part," said The Rev. William Tabbernee, head of the Oklahoma Conference of Churches. "Prayer puts us in touch with God, but it also helps us to focus on the fact that it is a partnership that we're involved in. We need to cooperate with God and all of humanity to be responsible stewards of the gifts God has given us through nature."

___

Follow Susan Montoya Bryan: http://www.twitter.com/susanmbryanNM

Source: http://news.yahoo.com/drought-across-west-spurs-resurgence-faith-080556490.html

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China, India PMIs show factory-sector growth stumbling

By Langi Chiang and Jonathan Standing

BEIJING (Reuters) - Factory-sector growth in China and India stumbled in April to further underline the impact of a fragile global economy, which is under pressure from the euro zone recession and fresh signals of weakness in the United States.

Reports on Wednesday showed manufacturing growth in the United States eased in April, while figures due later on Thursday from the euro zone are expected to show the sector there firmly entrenched in contractionary territory.

The purchasing managers indexes add to a string of economic data that has dented optimism seen at the start of the year, when there had been some signs the world economy was picking up.

The PMIs weighed on financial markets, partly reinforcing expectations that the European Central Bank will ease policy later on Thursday to help revive a regional economy where unemployment stands at a record high.

"Market tone is dictated by the tug-of-war between growth prospect worries and support from sustained monetary stimulus," said Hirokazu Yuihama, a senior strategist at Daiwa Securities in Tokyo.

The Chinese economy "is fragile and vulnerable to outside shocks, namely the U.S. economy, which is showing signs of pausing", Yuihama said.

China's official PMI fell in April to 50.6 from 50.9 in March, while the HSBC PMI dropped to 50.4 from 51.6 as new export orders fell. Fifty divides expansion from contraction on a monthly basis.

"The slower growth of manufacturing activity in April confirmed a fragile growth recovery of the Chinese economy as external demand deteriorated and renewed destocking pressures built up," said Qu Hongbin, chief China economist at HSBC.

"Looming deflationary pressures also suggest softer overall demand conditions. All this is likely to weigh on the labor market, which is likely to invite more policy responses in the coming months," Qu said.

The data underlined concerns that China's economic growth is struggling to pick up after a disappointing first quarter. A Reuters poll suggested growth would pick up in the second quarter to 8.0 percent after 7.7 percent in the first quarter, but analysts said forecasts were now at risk of a downgrade.

"The external sector is likely to be a major headwind for Chinese growth in the coming months," Barclays said in a client note.

"The across-the-board declines in the PMI reports point to soft industrial activity as we enter the second quarter. We maintain our growth forecast of 7.9 percent (2013 annual) which we have held since last December, but see some downside risks," Barclays said.

New export orders were rising in both South Korea and Japan in April but at a slower pace than in March, PMIs showed.

Japan's PMI, released earlier this week, was the highest in just over a year at 51.1, the latest evidence that Prime Minister Shinzo Abe's aggressive economic policies are benefiting the economy.

"This would represent a solid growth performance, maintaining the trend that was observed in the first quarter of the year and latest anecdotal evidence suggests a weaker yen is playing a part in the expansion by raising export volumes," said Paul Smith, senior economist at Markit, which produces the PMI data.

South Korea's overall PMI also rose in April, as domestic new orders more than offset the impact of the cooling in overseas orders.

India's factory sector, which is mostly geared to domestic demand, lost further momentum in April as output growth slipped to its weakest level in more than four years. However, unlike China, new export orders perked up to suggest some support for output in the months ahead.

Asia's third-largest economy is already facing its worst economic slowdown in a decade and faltering growth in the factory sector will bolster expectations for a central bank rate cut on Friday.

In the United States, the Institute for Supply Management said its PMI fell in April to 50.7 from 51.3 with a noticeable pull back in employment growth, pointing to a risk that the government's April jobs report due on Friday may fall short of expectations.

The Markit PMI also fell, to 52.1, its lowest level since October.

(Additional reporting by Yati Himatsingka in BANGALORE, Se Young Lee in SEOUL, Leah Schnurr in NEW YORK, Stanley White in TOKYO, Aileen Wang in BEIJING; Writing by Neil Fullick; Editing by Alex Richardson)

Source: http://news.yahoo.com/china-india-pmis-show-factory-sector-growth-stumbling-060025871.html

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Steven Spielberg to direct 'American Sniper'

LOS ANGELES (AP) ? Steven Spielberg has his sights set on his next project, a movie about former Navy SEAL sniper Chris Kyle.

A spokeswoman for DreamWorks Studios says the filmmaker will direct Bradley Cooper in an adaptation of the best-selling book "American Sniper."

"Spread" screenwriter Jason Hall wrote the script based on the autobiography of Kyle, who was killed along with a friend earlier this year while at a North Texas gun range. An Iraq war veteran who they were trying to help deal with PTSD is charged with the killings.

Kyle is considered to be the deadliest sniper in U.S. military history. At the time of his death, he was working on another book, "American Gun: A History of the U.S. in Ten Firearms."

The film will be a co-production of DreamWorks and Warner Bros.

Source: http://news.yahoo.com/steven-spielberg-direct-american-sniper-223741371.html

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Farm Business Management and Benchmarking - Grants.gov - Find ...

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The synopsis for this grant opportunity is detailed below, following this paragraph. This synopsis contains all of the updates to this document that have been posted as of 05/02/2013 . If updates have been made to the opportunity synopsis, update information is provided below the synopsis.

If you would like to receive notifications of changes to the grant opportunity click send me change notification emails . The only thing you need to provide for this service is your email address. No other information is requested.

Any inconsistency between the original printed document and the disk or electronic document shall be resolved by giving precedence to the printed document.

Document Type:	Grants Notice
Funding Opportunity Number:	USDA-NIFA-FBMB-004268
Opportunity Category:	Discretionary
Posted Date:	May 02, 2013
Creation Date:	May 02, 2013
Original Closing Date for Applications:	Jun 07, 2013 ??
Current Closing Date for Applications:	Jun 07, 2013 ??
Archive Date:	Jul 07, 2013
Funding Instrument Type:	Grant
Category of Funding Activity:	Agriculture Business and Commerce
Category Explanation:
Expected Number of Awards:
Estimated Total Program Funding:	$1,300,000
Award Ceiling:	$1,300,000
Award Floor:	$0
CFDA Number(s):	10.319 ?--? Farm Business Management and Benchmarking Competitive Grants Program
Cost Sharing or Matching Requirement:	No

Eligible Applicants

Others (see text field entitled "Additional Information on Eligibility" for clarification)
?

Additional Information on Eligibility:

Pursuant to 7 U.S.C. 450i(b)(7), eligible applicants means: (A) State agricultural experiment stations; (B) Colleges and universities; (C) University research foundations; (D) Other research institutions and organizations; (E) Federal agencies; (F) National laboratories; (G) Private organizations or corporations; (H) Individuals; or (I) Any group consisting of 2 or more of the entities described in subparagraphs (A) through (H).

Agency Name

National Institute of Food and Agriculture

Description

The Farm Business Management and Benchmarking (FBMB) Competitive Grants Program provides funds to (1) improve the farm management knowledge and skills of agricultural producers; and (2) establish and maintain a national, publicly available farm financial management database to support improved farm management.

Link to Additional Information

Farm Business Management and Benchmarking

If you have difficulty accessing the full announcement electronically, please contact:

NIFA Help Desk
Phone: 202-401-5048
Business hours are M-F, 7:00 am -5:00 pm ET, excluding Federal holidays If you have any questions related to preparing application content

Synopsis Modification History

There are currently no modifications for this opportunity.

?

Source: http://www.grants.gov/search/search.do?mode=VIEW&oppId=232934

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Bird fossil sheds light on how swift and hummingbird flight came to be

Wednesday, May 1, 2013

A tiny bird fossil discovered in Wyoming offers clues to the precursors of swift and hummingbird wings. The fossil is unusual in having exceptionally well-preserved feathers, which allowed the researchers to reconstruct the size and shape of the bird's wings in ways not possible with bones alone.

Researchers spotted the specimen ? the nearly complete skeleton of a bird that would have fit in the palm of your hand and weighed less than an ounce ? while working at the Field Museum of Natural History in Chicago.

The newly discovered bird was named Eocypselus rowei, in honor of John W. Rowe, Chairman of the Field Museum's Board of Trustees.

First collected in southwestern Wyoming in a fossil site known as the Green River Formation, E. rowei lived roughly 50 million years ago, after the dinosaurs disappeared but before the earliest humans came to be.

E. rowei was a tiny bird ? only twelve centimeters from head to tail. Feathers account for more than half of the bird's total wing length.

To find out where the fossil fit in the bird family tree, the researchers compared the specimen to extinct and modern day species. Their analyses suggest that the bird was an evolutionary precursor to the group that includes today's swifts and hummingbirds.

Given the differences in wing shape between these two closely related groups of birds, scientists have puzzled over how swift and hummingbird flight came to be. Finding fossil relatives like this specimen is key to figuring that out, the researchers say.

"This fossil bird represents the closest we've gotten to the point where swifts and hummingbirds went their separate ways," said lead author Daniel Ksepka of the National Evolutionary Synthesis Center in Durham, North Carolina.

Hummingbirds have short wings relative to their bodies, which makes them good at hovering in mid-air. Swifts have super-long wings for gliding and high-speed flight. But the wings of E. rowei were somewhere in between.

"[Based on its wing shape] it probably wasn't a hoverer, like a hummingbird, and it probably wasn't as efficient at fast flight as a swift," Ksepka said.

The shape of the bird's wings, coupled with its tiny size, suggest that the ancestors of today's swifts and hummingbirds got small before each group's unique flight behavior came to be. "Hummingbirds came from small-bodied ancestors, but the ability to hover didn't come to be until later," Ksepka explained.

Closer study of the feathers under a scanning electron microscope revealed that carbon residues in the fossils ? once thought to be traces of bacteria that fed on feathers ? are fossilized melanosomes, tiny cell structures containing melanin pigments that give birds and other animals their color. The findings suggest that the ancient bird was probably black and may have had a glossy or iridescent sheen, like swifts living today. Based on its beak shape it probably ate insects, the researchers say.

The other authors of this study were Julia Clarke, Sterling Nesbitt and Felicia Kulp of the University of Texas at Austin, and Lance Grande of the Field Museum of Natural History.

The results will appear in the May 1 issue of the journal Proceedings of the Royal Society B.

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Ksepka, D., et al. (2013). "Fossil evidence of wing shape in a stem relative of swifts and hummingbirds (Aves, Pan-Apodiformes)." Proceedings of the Royal Society B.

National Evolutionary Synthesis Center (NESCent): http://www.nescent.org

Thanks to National Evolutionary Synthesis Center (NESCent) for this article.

This press release was posted to serve as a topic for discussion. Please comment below. We try our best to only post press releases that are associated with peer reviewed scientific literature. Critical discussions of the research are appreciated. If you need help finding a link to the original article, please contact us on twitter or via e-mail.

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Source: http://www.labspaces.net/128061/Bird_fossil_sheds_light_on_how_swift_and_hummingbird_flight_came_to_be

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