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November 11, 2009, 8:00 AM CT

Eyeless, mouthless worms lurk in the dark

Eyeless, mouthless worms lurk in the dark
This photograph shows a female of an as yet un-named boneworm in the genus Osedax, which has been carefully removed from the whale bone in which it was growing. This worm has green, feathery palps, which extract oxygen from seawater. At its lower end are an ovisac and bulbous "roots," which would normally be embedded in the whale bone.
Image: © 2009 Greg Rouse
It sounds like a classic horror story-eyeless, mouthless worms lurk in the dark, settling onto dead animals and sending out green "roots" to devour their bones. In fact, such worms do exist in the deep sea. They were first discovered in 2002 by scientists at the Monterey Bay Aquarium Research Institute (MBARI), who were using a robot submarine to explore Monterey Canyon. But that wasn't the end of the story. After "planting" several dead whales on the seafloor, a team of biologists recently announced that as a number of as 15 different species of boneworms may live in Monterey Bay alone.

After years of study, the scientists have begun to piece together the bizarre story of the boneworms, all of which are in the genus Osedax. The worms start out as microscopic larvae, drifting through the darkness of the deep sea. At some point they encounter a large dead animal on the seafloor. It appears to be a whale, an elephant seal, or even the carcass of a cow that washed out to sea during a storm. Following chemical cues, the tiny larvae settle down onto the bones of the dead animal.

Once settled, the boneworms grow quickly, like weeds after a rain. One end of each worm develops feathery palps, which extract oxygen from seawater. The other end of the worm develops root-like appendages that grow down into the bone. Bacteria within these roots are believed to digest proteins and perhaps lipids within the bones, providing nutrition for the worms.........

Posted by: Kelly      Read more         Source


November 10, 2009, 9:00 AM CT

Fig-wasps travel hundreds of miles

Fig-wasps travel hundreds of miles
Illustrations and photographs credit and © Simon van Noort (Iziko Museums of Cape Town)
They may only be 1.5mm in size, but the tiny wasps that pollinate fig trees can travel over 160km in less than 48 hours, as per research from researchers at the University of Leeds. The fig wasps are transporting pollen ten times further than previously recorded for any insect.

The fig wasps travel these distances in search of trees to lay their eggs, which offers hope that trees pollinated by similar creatures have a good chance of surviving if they become isolated through deforestation.

"Fig trees provide very important food for vertebrates," explains Dr Stephen Compton of the University's Faculty of Biological Sciences. "More birds and animals feed on fig trees than on any other plant in the rainforest. Our research shows that trees pollinated by this type of insect should be very resistant to forest fragmentation".

"Fig wasps are weak flyers," added Dr Compton. "They fly up in an air column and are then carried by wind until they sense host figs at which point they drop close to the ground and hunt out the scent of the tree which is specific to them.

"As adult wasps live for just 48 hours, they must have travelled these distances incredibly fast. It took our field researchers and volunteers nearly two weeks to walk 250km and map the fig trees used in the research".........

Posted by: Kelly      Read more         Source


November 5, 2009, 8:42 AM CT

Making better broccoli

Making better broccoli
Carotenoidsfat-soluble plant compounds found in some vegetablesare essential to the human diet and reportedly offer important health benefits to consumers. Plant carotenoids are the most important source of vitamin A in the human diet; the carotenoids lutein and zeaxanthin, found in corn and leafy greens vegetable such as kale, broccoli, and spinach, are widely considered to be valuable antioxidants capable of protecting humans from chronic diseases including age-related macular degeneration, cancer, and cardiovascular disease.

Vegetables in the cabbage family (such as kale, cauliflower, and broccoli) have long been known as particularly good sources of dietary carotenoids. Recently, broccoli has emerged as the stand-out member of the species, providing more carotenoids to American consumers than any of its cabbage-family relatives. Yet, little has been understood about the carotenoid make-up of this popular green vegetableuntil now.

Mark W. Farnham of the U.S. Department of Agriculture, Agricultural Research Service, Charleston, South Carolina, and Dean A. Kopsell from the Plant Sciences Department, University of Tennessee, Knoxville, designed a research study aimed at finding out more about the carotenoid content of field-grown broccoli and determining the effects of genetics and the environment on carotenoid levels. The duo's research confirmed that broccoli heads contain abundant levels of lutein, an antioxidant usually thought to provide nutritional support to eyes and skin. Other carotenoids like beta-carotene, violaxanthin, neoxanthin, and antheraxanthin were also found in broccoli heads, but lutein was clearly the most significant, accounting for about half of all carotenoids measured.........

Posted by: Erica      Read more         Source


November 5, 2009, 8:39 AM CT

Indoor plants to fight air pollution

Indoor plants to fight air pollution
Hemigraphis alternata, or purple waffle plant, one of the highest rated ornamentals for removing indoor air pollutants.

Credit: Photo courtesy of Dr. Stanley Kays

Air quality in homes, offices, and other indoor spaces is becoming a major health concern, especially in developed countries where people often spend more than 90% of their time indoors. Surprisingly, indoor air has been reported to be as much as 12 times more polluted than outdoor air in some areas. Indoor air pollutants emanate from paints, varnishes, adhesives, furnishings, clothing, solvents, building materials, and even tap water. A long list of volatile organic compounds, or VOCs [including benzene, xylene, hexane, heptane, octane, decane, trichloroethylene (TCE), and methylene chloride], have been shown to cause illnesses in people who are exposed to the compounds in indoor spaces. Acute illnesses like asthma and nausea and chronic diseases including cancer, neurologic, reproductive, developmental, and respiratory disorders are all associated with exposure to VOCs. Harmful indoor pollutants represent a serious health problem that is responsible for more than 1.6 million deaths each year, as per a 2002 World Health Organization report.

Stanley J. Kays, Department of Horticulture, University of Georgia, was the lead researcher of a study published in HortScience that tested ornamental indoor plants for their ability to remove harmful VOCs from indoor air. As per Kays, some indoor plants have the ability to effectively remove harmful VOCs from the air, and not only have the ability to improve our physical health, but also have been shown to enhance our psychological health. Adding these plants to indoor spaces can reduce stress, increase task performance, and reduce symptoms of ill health.........

Posted by: Erica      Read more         Source


November 5, 2009, 8:37 AM CT

Seeking flower variety

Seeking flower variety
Florists and other retailers who sell flowers and plants can now add another tool to their marketing kit. A recent study of "consumption values" may help them understand what influences consumers' choices in regard to floral purchases, and how to better design marketing efforts and purchase stock that can increase customers and sales.

Li-Chun Huang from National Taiwan University and Tzu-Fang Yeh from Da-Yeh University headed a research project that reviewed the differences in floral consumption values across consumer groups (the full study appears in a recent issue of HortTechnology).

A consumer survey was conducted in cities and rural areas in Taiwan in 2006 where 677 participants were surveyed. As per responses to a survey question that asked whether they purchased flowers, participants were divided into two categories: ''users'' and ''nonusers'' of flowers.

The majority of survey participants indicated that the following values (in descending order) influenced their floral purchases: showing care to others, emotion conditioning, and "sensory hedonics", a phenomenon in which consumers perceive the value of flowers based on touching, smelling, or tasting them. Interestingly, those participants identified as "heavy users" of flowers revealed different priorities, rating "emotion conditioning" as more important than "showing care to others". The scientists note that this implies that "heavy users" make more frequent floral purchase flowers partly because they are more emotionally stimulated by flowers. Heavy users also rated "curiosity fulfillment" higher, leading to them to look for more novelty and variety when purchasing flowers.........

Posted by: Erica      Read more         Source


November 4, 2009, 8:19 AM CT

Sustainably grown garlic

Sustainably grown garlic
Colorful new varieties of garlic are becoming popular with consumers.

Credit: Photo courtesy of Gayle M. Volk

Consumer interest in new and diverse types of garlic is on the rise. Fueled by factors including the growth of the "local foods" movement, interest in world cuisines, and widespread reports touting its numerous health benefits, demand for high-quality, locally grown garlic is increasing throughout the U.S.

While most grocery stores in carry the familiar white, "softneck" garlic (which is most often imported), varieties of "hardneck" garlic in colorful hues of purple, magenta, pink, and white are becoming more available at local vegetable stands and through direct-marketing programs. The results of a recent study of 10 garlic cultivars can help farmers identify niche regional markets and offer new, in-demand garlic varieties to consumers.

Hundreds of garlic (Allium sativum L.) cultivars are available from seed companies, retailers, and germplasm collections. Increasingly, growers purchase bulbs from nonlocal sources and are often disappointed by unpredictable yields. Garlic bulbs resulting from seed stock purchased in other regions may not display the characteristicssuch as bulb size, shape, and colorfeatured in the catalogs.

Gayle M. Volk of the National Center for Genetic Resources Preservation, U.S. Department of Agriculture's Agricultural Research Service in Fort Collins, and David Stern of the Garlic Seed Foundation authored a study designed to determine which garlic traits are stable and which traits vary depending on where the garlic is grown. As per the study published in a recent issue of HortScience and funded primarily by the Northeast Sustainable Agricultural Research and Education program, previous research has shown that traits such as clove number, clove skin coloration, and topset number are representative of cultivar type across growth locations, whereas "phenotypic" traits such as bulb wrapper color, bulb size, and bulb elemental composition are specific to sites.........

Posted by: Erica      Read more         Source


November 4, 2009, 8:16 AM CT

Pecan trees benefit from thinning

Pecan trees benefit from thinning
Mechanical thinning of pecan trees is shown using a tree shaker with a hydraulic shaker head.

Credit: Photo courtesy of Dr. M. Lenny Wells

Pecan trees, like many fruit trees, have a tendency to bear fruit in cycles, producing a large crop in one or two years, followed by one or two years with little or no crop. This cycle, called "alternate bearing", is the most profit-limiting biological problem facing pecan producers; the inconsistent production pattern creates supply and marketing challenges that can have severe negative effects on the pecan industry.

Producers have experienced success using mechanical fruit thinning as a way to minimize the effects of alternate bearing on several pecan cultivars. While the protocol for mechanical crop thinning has been established for some pecan cultivars grown in Oklahoma and Kansas, little research has been conducted regarding the economic value and potential profitability of fruit thinning of cultivars found in the southeastern United States. To address this issue, researchers at the University of Georgia's Department of Horticulture studied the effects of mechanical fruit thinning on pecan yield, nut quality, and profitability using 'Sumner' and 'Cape Fear' pecan trees, two important cultivars prevalent in areas of the southeastern U.S. The research study was published in a recent issue of HortTechnology

Ten 20-year-old trees of both 'Sumner' and 'Cape Fear' were used for the study. Trees grown in Tifton loamy sand soil in a commercial pecan orchard in Irwin County, Georgia, were used for the study. The trees were spaced 40 x 40 feet and were drip-irrigated. Treatments were replicated five times in a randomized complete-block design. Five trees of each cultivar were mechanically thinned using a tree shaker with a hydraulic shaker heada process called trunk shakingto remove 30% to 40% of the fruit on each tree, and five trees were not thinned.........

Posted by: Erica      Read more         Source


November 4, 2009, 8:15 AM CT

For African violets

For African violets
People like to feel the soft, often hairy leaves of African violets, but touching the leaves can cause damage to the plants.

Credit: Photo by Donna Dollins
African violets have a mixed reputation. Their delicate, colorful flowers and furry, soft leaves make them a favorite among home gardeners and growers. But the striking plants are often regarded as temperamental: a precise recipe of light, moisture, warm temperatures, high humidity, and fertilizer is mandatory to encourage african violets to grow and flower.

A recently published study by researchers Julia C. Brotton and Janet C. Cole from the Department of Horticulture and Landscape Architecture at Oklahoma State University (in a recent issue of HortTechnology) could provide african violet enthusiasts with important care information about the finicky flower.

Because of their brightly colored flowers and hairy leaves, people are attracted to african violets and often want to touch the leaves and flowers. But how does all this attention affect the plants? The research team set out to determine the effect of "brushing" african violet leaves on plant growth and quality. Cole explained, "Because (african violet) growers work in conditions that can contribute to the development of dry, irritated skin, a number of growers use body lotions to help soothe and moisturize their dry skin. A number of consumers also use these products. Our study researched whether touching or "brushing" african violet leaves causes damage, especially when body lotion or other skin care products have been applied to hands before touching the plants".........

Posted by: Erica      Read more         Source


November 4, 2009, 8:10 AM CT

White sharks in the north Pacific

White sharks in the north Pacific
A white shark tagged with both acoustic (front) and pop-up satellite (rear) tags. The acoustic tag is detected when the shark swims within 250 m of a listening station, while the pop-up satellite tag records information about location, temperature and depth -- and relays it to the laboratory when the tag releases itself from the shark.

Credit: Courtesy: TOPP

The white shark appears to be the ultimate loner of the ocean, cruising thousands of miles in a solitary trek, but a team of scientists has discovered that the sharks have maintained such a consistent pattern of migration that over tens of thousands of years the white sharks in the northeastern Pacific Ocean have separated themselves into a population genetically distinct from sharks elsewhere in the world.

"White sharks are a large, highly mobile species," said Salvador Jorgensen, a postdoctoral scholar at Stanford's Hopkins Marine Station. "They can go just about anywhere they want in the ocean, so it's really surprising that their migratory behaviors lead to the formation of isolated populations".

Researchers with the Tagging of Pacific Predators (TOPP) program combined satellite tagging, passive acoustic monitoring and genetic tags to study white sharks (Carcharodon carcharias) popularly known as great white sharks in the North Pacific. The team consisted of scientists from Stanford University, University of California-Davis, Point Reyes Bird Observatory and the Pelagic Shark Research Foundation, and the details of their study are to be published online Nov. 3 by the Proceedings of the Royal Society B

The fact that the northeastern Pacific white sharks undergo such a consistent, large-scale migration, and that they are all closely related and distinct from other known white shark populations, suggests that it is possible to conduct long-term population evaluation and monitoring of these animals.........

Posted by: Kelly      Read more         Source


November 4, 2009, 7:59 AM CT

Cultured pearls from the queen conch

Cultured pearls from the queen conch
The queen conch is the largest molluscan gastropod of the six conch species found in the shallow seagrass beds of Florida, the Bahamas, Bermuda, the Caribbean Islands and the northern coasts of Central and South America.

Credit: FAU's Harbor Branch Oceanographic Institute

For more than 25 years, all attempts at culturing pearls from the queen conch (Strombus gigas) have been unsuccessfuluntil now. For the first time, novel and proprietary seeding techniques to produce beaded (nucleated) and non-beaded cultured pearls from the queen conch have been developed by researchers from Florida Atlantic University's Harbor Branch Oceanographic Institute (HBOI). With less than two years of research and experimentation, Drs. Hctor Acosta-Salmn and Megan Davis, co-inventors, have produced more than 200 cultured pearls using the techniques they developed. Previous to this breakthrough, no high-quality queen conch pearl had been cultured. This discovery opens up a unique opportunity to introduce a new gem to the industry. This significant accomplishment is comparable to that of the Japanese in the 1920s when they commercially applied the original pearl culture techniques developed for pearl oysters.

HBOI has been working with the Gemological Institute of America (GIA) to conduct extensive laboratory testing of the queen conch cultured pearls. In its independent analysis, GIA used techniques that included conventional gemological examination, chemical composition, spectroscopy, spectrometry and microscopy. HBOI and GIA plan to jointly publish the results of these trials in an upcoming issue of GIA's scientific journal, Gems & Gemology........

Posted by: Kelly      Read more         Source

   

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