February 26, 2009, 11:14 PM CT

Consumer Preferences For Strawberries

Fresh strawberries. Just the mention of this iconic spring and early summer fruit can elicit mouthwatering memories of shortcake, fruity drinks and sweet desserts. Scientists interested in learning more about this evocative fruit have determined that "sensory quality" of strawberries, a strong influence on consumer preferences, is the result of a complex balance of sweetness, aroma, texture, and appearance.

The goals of a recent study by a research team from the University of Florida's Gulf Coast Research and Education Center in Wimauma, Florida and the USDA Agricultural Research Service (ARS) in Winter Haven, were to reveal factors affecting the "eating quality" of promising strawberry selections in the University of Florida breeding program, as well as the impact of harvest date on the fruits' chemical and sensory characteristics.

As per main author Anne Plotto of the USDA-ARS, the scientists reviewed five selections and one cultivar of the University of Florida breeding program as well as two new cultivars from Australia ('Rubygem' and 'Sugarbaby').

The sensory study took place at the University of Florida's Gulf Coast Research and Education Center during 2006 and 2007. Participants were employees from, and visitors to, the center. In 2006, 50 and 51 panelists participated in the February and March panels, respectively, with 62% to 63% female panelists. In 2007, 60 to 66 panelists (36% to 52% female panelists) participated in the taste panels. Panelist ages ranged from younger than 26 to older than 65 years old, with the majority of panelists between 36 and 55 years old......... Posted by: Erica      Read more         Source

February 26, 2009, 11:10 PM CT

Antioxidants in Midwestern black raspberries

Black raspberries have been studied for decades by researchers and medical scientists interested in the fruits' apparent ability to limit the onset or severity of degenerative diseases, including cancer.

The fruit of a number of popular berries, including blackberries, blueberries, strawberries, elderberries, grapes, and plums, are known to have strong antioxidant capacity, mainly as a result of high levels of anthocyaninschemicals that give plants their vibrant colorsand other phenolic compounds. The darker the fruit, the more anthocyanins are present. Anthocyanins appear to work by inhibiting compounds that weaken the immune system and stimulate tissue inflammation. They can also destroy harmful free-radical molecules that attack cells and cause aging, heart disease, and cancer.

The prospective health benefits of black raspberries and other antioxidant-rich produce has led to increased consumer awareness and demand for fresh, locally produced fruit.

A research study presented in the journal HortScience was designed to determine whether where black raspberries are grown influences the antioxidant level in the berries. The research group, headed by Mustafa Ozgen from the Department of Horticulture at Gaziosmanpa University, Tokat, Turkey, included Faith J. Wyzgoski, The Ohio State University at Mansfield, Artemio Z. Tulio, Jr., Aparna Gazula, A. Raymond Miller, and Joseph C. Scheerens from the Ohio Agricultural Research and Development Center, R. Neil Reese from South Dakota State University, and Shawn R. Wright of The Ohio State University South Centers......... Posted by: Erica      Read more         Source

February 26, 2009, 11:08 PM CT

Study of orchard ground cover management systems

Orchard floor and groundcover management is important to fruit growers, affecting the efficiency of orchard operations, fruit tree performance, and soil quality.

Herbicide-treated tree rows with mowed grass "drive lanes" are the most widely used orchard groundcover management systems (GMS) in North America and Europe; the system is widely considered to be the most efficient and least expensive GMS.

Due to increased concerns about the environmental impact of herbicides and mechanical soil tillage, alternative methods are being sought to suppress orchard weeds and maintain soil quality. In response to environmental concerns, researchers have tested different types of cover crops and mulches, especially biomass, inorganic, and geotextile mulch. Eventhough root systems play an important role in tree growth and development, little is known about differential GMS effects on orchard root growth and distribution.

Scientists Shengrui Yao (University of Minnesota) and Ian A. Merwin and Michael G. Brown (Cornell University) coauthored a study that compared apple root density and distribution, root turnover, and root lifespan of trees after 10 years under different GMS therapys. The study was reported in the journal HortScience

The experiment involved the use of two minirhizotrons, or root observation tubes, installed on both sides of one tree in three replicates for each GMS therapy. Roots were observed by camera at two or three weekly intervals during the growing seasons of 2002 and 2003, and from whole tree excavations in 2000......... Posted by: Erica      Read more         Source

February 25, 2009, 11:01 PM CT

Cells with double vision

The complexity of the human brain is remarkable: It contains billions of nerve cells, each of which is connected with its neighbours via a number of thousands of contacts. The result is a multifaceted network which stores and processes a number of types of information. In comparison, the brain of a fly seems fairly simple with its 250 000 nerve cells. For example, a small network of only 60 nerve cells in each cerebral hemisphere suffices the blowfly to integrate visual motion information. The resulting information is then used in the control and correction of the fly's flight manoeuvres. However, flies clearly demonstrate just how efficient these 60 cells actually are when they dodge obstacles while flying at high speed and land upside-down on the ceiling. No wonder neurobiologists find the brain of the fly so fascinating!

Rationing resources.

Thanks to the comparatively small number of nerve cells in the fly's visual flight control centre, the connections and functions of the cells involved can be examined in greater detail. It soon became apparent that the 60 nerve cells are further sub-divided into several individual cell groups, each of which is responsible for the processing of certain patterns of movement. A group of ten cells, known as the VS-cells, respond to rotational movements of the fly, for example. Each of these ten cells receives its visual information from only a narrow vertical strip of the fly's eye - the cell's "receptive field". Since the VS-cells are arranged parallel to each other, the fly's field of vision is completely covered by the vertical strips of the ten cells on each side of the fly's brain (the figure shows three of the ten VS-cells)......... Posted by: Janet      Read more         Source

February 25, 2009, 5:25 AM CT

How did the prehistoric reptiles take first flight?

In the Mesozoic Era, 70 million years before birds first conquered the skies, pterosaurs dominated the air with sparrow- to Cessna-sized wingspans. Scientists suspected that these extinct reptiles sustained flight through flapping, based on fossil evidence from the wings, but had little understanding of how pterosaurs met the energetic demands of active flight.

A newly released study published recently in the journal PLoS ONE by scientists from Ohio University, College of the Holy Cross and the University of Leicester explains how balloon-like air sacs, which extended from the lungs to inside the skeleton of pterosaurs, provided an efficient breathing system for the ancient beasts. The system reduced the density of the body in pterosaurs, which in turn allowed for the evolution of the largest flying vertebrates.

"We offer a reconstruction of the breathing system in pterosaurs, one that proposes the existence of a mechanism with the same essential structure to that of modern birds - except 70 million years earlier," said co-author of study Leon Claessens, an assistant professor of biology at the College of the Holy Cross.

The system would have facilitated the necessary gas exchange to enable sustained activity, added co-author Patrick O'Connor, an assistant professor of biomedical sciences at the Ohio University College of Osteopathic Medicine......... Posted by: Kelly      Read more         Source

February 24, 2009, 6:25 AM CT

Mystery of deep-sea fish with tubular eyes and transparent head

Scientists at the Monterey Bay Aquarium Research Institute recently solved the half-century-old mystery of a fish with tubular eyes and a transparent head. Ever since the "barreleye" fish Macropinna microstoma was first described in 1939, marine biologists have known that it's tubular eyes are very good at collecting light. However, the eyes were thought to befixed in place and seemed to provide only a "tunnel-vision" view of whatever was directly above the fish's head. A new paper by Bruce Robison and Kim Reisenbichler shows that these unusual eyes can rotate within a transparent shield that covers the fish's head. This allows the barreleye to peer up at potential prey or focus forward to see what it is eating.

Deep-sea fish have adapted to their pitch-black environment in a variety of amazing ways. Several species of deep-water fishes in the family Opisthoproctidae are called "barreleyes" because their eyes are tubular in shape. Barreleyes typically live near the depth where sunlight from the surface fades to complete blackness. They use their ultra-sensitive tubular eyes to search for the faint silhouettes of prey overhead.

Eventhough such tubular eyes are very good at collecting light, they have a very narrow field of view. Furthermore, until now, most marine biologists believed that barreleye's eyes were fixed in their heads, which would allow them to only look upward. This would make it impossible for the fishes to see what was directly in front of them, and very difficult for them to capture prey with their small, pointed mouths......... Posted by: Kelly      Read more         Source

February 24, 2009, 6:21 AM CT

Building a Better Protein

Proteins are widely viewed as a promising alternative to synthetic chemicals in everything from medications to hand lotion. The naturally occurring molecules have been shown to be more efficient and effective than a number of of the most sophisticated chemical compounds on the market. But outside the controlled confines of the lab bench, proteins quickly change structure, causing irreversible damage to their functionality and often safety.

Researchers are now searching for ways to increase the stability of proteins. In new research published Feb. 5 in the online Early Edition of the Proceedings of the National Academy of Sciences (PNAS), Rensselaer Senior Constellation Professor George Makhatadze and colleagues detail a targeted strategy to substantially increase the thermodynamic stability of nearly any protein, while preserving its unique function. Their redesign technique creates proteins that remain stable at temperatures 10 degrees Celsius higher than normal.

To achieve these results, the scientists used high-powered computers to create new and improved versions of two human enzymes. The enzymes are specific types of protein. The two enzymes in the study vary widely in size and functionality, yet both showed substantial increases in stability without loss of function in the body. This supports the idea that the stability of a number of other proteins could also be greatly stabilized, as per Makhatadze. The scientists are now looking to use the technique to improve that stability of specific proteins with strong industrial and drug development applications......... Posted by: Janet      Read more         Source

February 20, 2009, 6:19 AM CT

Gene to reduce wheat yield losses

A new gene that provides resistance to a fungal disease responsible for millions of hectares of lost wheat yield has been discovered by researchers from the US and Israel.

"This is the first step to achieving more durable resistance to a devastating disease in wheat," said Dr Cristobal Uauy, co-author of the report, recently appointed to the John Innes Centre in Norwich.

Resistance to stripe rust has previously been achieved using genes that are specific to single races of the disease. Unfortunately, each of these genes has had limited durability in the field because the pathogen has mutated to overcome them.

In the paper to be published in Science Express tomorrow, the international team of researchers report finding a novel type of gene in wild wheat that is absent in modern pasta and bread wheat varieties.

"This gene makes wheat more resistant to all stripe rust fungus races tested so far," said Dr Uauy.

The gene confers resistance at relatively high temperatures, and a focus of Dr Cristobal Uauy's research at JIC will be to test how effective it is in UK-adapted varieties.

Bread wheat provides about 20 per cent of the calories eaten by humankind and is the UK's biggest crop export.

Dr Uauy has recently been appointed at JIC. He will lead a research collaboration with the National Institute of Agricultural Botany (NIAB) designed to deliver practical benefits to agriculture. Research results will be made available to breeders, so they can be deployed into modern varieties for farmers......... Posted by: Erica      Read more         Source

February 16, 2009, 10:24 PM CT

When fish farms are built along the coast

If you are a fish eater, it's likely that the salmon you had for dinner was not caught in the wild, but was instead grown in a mesh cage submerged in the open water of oceans or bays. Fish farming, a relatively inexpensive way to provide cheap protein to a growing world population, now supplies, by some estimates, 30 percent of the fish consumed by humans.

Two hundred and twenty species of finfish and shellfish are now grown in farms.

Intuitively, it seems a good ideathe more fish grown in pens, the fewer need be taken from wild stocks in the sea. But marine aquaculture can have some nasty side effects, particularly when the pens are set near sensitive coastal environments. All those fish penned up together consume massive amounts of commercial feed, some of which drifts off uneaten in the currents. And the crowded fish, naturally, defecate and urinate by the tens of thousands, creating yet another unpleasant waste stream.

The wastes can carry disease, causing damage directly. Or the phosphate and nitrates in the mix may feed an algae bloom that sucks the oxygen from the water, leaving it uninhabitable, a phenomenon long linked to fertilizer runoff.

It has been widely assumed that the effluent from pens would be benignly diluted by the sea if the pens were kept a reasonable distance from shore, said Jeffrey Koseff, a professor of civil and environmental engineering and co-director of Stanford's Woods Institute for the Environment. But early results from a new Stanford computer simulation based on sophisticated fluid dynamics show that the icky stuff from the pens will travel farther, and in higher concentrations, than had been generally assumed, Koseff said......... Posted by: Kelly      Read more         Source

February 16, 2009, 9:57 PM CT

Viewing all the 15 million atoms in viral coat

If a picture is worth a thousand words, then Rice University's precise new image of a virus' protective coat is seriously undervalued. More than three years in the making, the image contains some 5 million atoms -- each in precisely the right place -- and it could help researchers find better ways to both fight viral infections and design new gene therapies.

The stunning image, which appears online this week in the Proceedings of the National Academy of Sciences, reveals the structure of a type of protein coat shared by hundreds of known viruses containing double-stranded RNA genomes. The image was painstakingly created from hundreds of high-energy X-ray diffraction images and paints the clearest picture yet of the viruses' genome-encasing shell called a "capsid".

"When these viruses invade cells, the capsids get taken inside and never completely break apart," said lead researcher Jane Tao, assistant professor of biochemistry and cell biology at Rice.

Capsids come into play because viruses can reproduce themselves only by invading a host cell and highjacking its biochemical machinery. But when they invade, viruses need to seal off their genetic payload to prevent it from being destroyed by the cell's protective mechanisms.

Though there are more than 5,000 known viruses, including whole families that are marked by wide variations in genetic payload and other characteristics, most of them use either a helical or a spherical capsid......... Posted by: Janet      Read more