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Quotes of the Day

The scientific observer of Nature is a kind of mystic seeker in the act of prayer.
(Muhammad Iqbal)

SPECIES OF THE DAY

Huso huso (Beluga Sturgeon)
The Beluga Sturgeon, Huso huso, is listed as ‘Endangered’ on the IUCN Red List of Threatened Species™. Also known as the Giant Sturgeon, it is the largest sturgeon in the world, and the largest freshwater fish in Europe, where it occurs primarily in and around the Caspian, Black, and occasionally in the Adriatic and Mediterranean Seas.
Overfishing, habitat loss and pollution threaten the survival of the Beluga Sturgeon. Its eggs are highly prized as beluga caviar, and illegal fishing is reported to be common. Pollution, dams and silting can cause habitat destruction by damaging coastal waters and altering river courses. For example, the Volgograd Dam in Russia has effectively blocked access to almost all of the species’ spawning grounds along the Volga River.
The majority of the Beluga Sturgeon population is now supported artificially, with hatcheries thought to be the sole reason the species still survives in the Caspian Sea. The United States is the biggest importer of beluga caviar, and has now listed the species as ‘Threatened’ under the Endangered Species Act, suspending imports.

Popular Nanoparticle Causes Toxicity in Fish, Study Shows

Tested on fathead minnows -- an organism often used to test the effects of toxicity on aquatic life -- nanosilver suspended in solution proved toxic and even lethal to the minnows. When the nanosilver was allowed to settle, the solution became several times less toxic but still caused malformations in the minnows.

"Silver nitrate is a lot more toxic than nanosilver, but when nanosilver was sonicated, or suspended, its toxicity increased tenfold," said Maria Sepúlveda, an assistant professor of forestry and natural resources whose findings were published in the journal Ecotoxicology. "There is reason to be concerned."

Sepúlveda and doctoral student Geoff Laban exposed fathead minnows to nanosilver at several stages of their development, from embryo to the point where they swim up from the bottom of their habitats to eat for the first time. Even without sonication, nanosilver caused malformations that included head hemorrhages and edema, and ultimately proved lethal.

Using electron microscopy, Sepúlveda was able to detect nanosilver particles measuring 30 nanometers or less inside the minnow embryos. Thirty nanometers is more than 3,000 times smaller than the diameter of a human hair.

"These nanosilver particles are so small they are able to cross the egg membranes and move into the fish embryos in less than a day," Sepúlveda said. "They had a potentially high dose of silver in them."

Nanosilver is growing in popularity as a component of many products. It is used to kill bacteria in goods such as odor-control clothing, countertops, cutting boards and detergents. Currently, there are few regulations for nanosilver's applications in products, but Ron Turco, professor of agronomy and the paper's co-author, said the Environmental Protection Agency is reviewing the situation.

Turco also indicated there has been little work done to estimate the current level of nanosilver being released into the environment.

"Silver has been used in the past as an antimicrobial agent. It's a known toxicant to microorganisms," he said. "Nanosilver is being considered by the EPA for environmental exposure profiling, much like a pesticide."

Turco said it's unclear how nanosilver exposure might affect human health; however, he said that silver solutions have been considered by some to be a probiotic, and low dosages are sometimes consumed for intestinal health.

"The use of nanosilver could provide a number of sanitary benefits if used properly," Turco said. "However, the indiscriminate inclusion of nanosilver into products to simply allow them to say they are antimicrobial is creating a cautionary issue."

Long-Distance Migration Shapes Butterfly Wings

As part of a National Science Foundation and UGA-funded study, researchers in the Warnell School of Forestry and Natural Resources and the Odum School of Ecology examined the size and shape of monarchs from migratory and non-migratory populations using sophisticated computer imaging that was able to measure precise details about the insects' wings. Warnell doctoral candidate Andy Davis and Odum Associate Professor Sonia Altizer compared migratory monarchs from the eastern and western U.S. to those in Hawaii, Costa Rica, South Florida and Puerto Rico that do not migrate. They also measured the wings of lab-grown monarchs to rule out environmental causes of differences in size and shape, and to demonstrate a genetic basis for variation in wing traits among individual monarchs. Altizer and Davis' findings were recently published in the online edition of the scientific journal Evolution.

The findings in monarchs were consistent with previous studies comparing migratory and non-migratory bird species, which indicate that the best shape for long-distance flight involves long wings with a narrow tip to help reduce drag. In addition to their findings on wing size and shape, the team also found that monarchs from the two migratory populations in the U.S. differed in body size, suggesting that each population could have adapted to the demands of migration in subtly different ways. Larger bodies might help eastern monarchs, with their much longer migration, carry fat deposits to fuel the long journey and five-month overwintering period in Mexico.

Husn e Haqiqi

Allah Hoo

Fisheries and Aquaculture Face Multiple Risks from Climate Change

The study, 'Climate change implications for fisheries and aquaculture', is one of the most comprehensive surveys to date of existing scientific knowledge on the impacts of climate change on fisheries and aquaculture. Covering some 500 scientific papers, the picture the FAO review paints is one of an already-vulnerable sector facing widespread and often profound changes.


The report includes contributions from experts from around the world, including Dr Tim Daw and Prof Katrina Brown of the School of International Development and Prof Neil Adger of the School of Environmental Sciences at UEA. Other contributors come from the WorldFish Center, Globec, Network of Aquaculture Centres in Asia-Pacific, and Fisheries and Oceans Canada.

Dr Daw and Profs Adger and Brown co-authored the chapter 'Climate change and capture fisheries: potential impacts, adaptation and mitigation', which looks at the social vulnerability of fisherfolk to climate change. "Marine and freshwater ecosystems will be profoundly affected by processes like ocean acidification, coral bleaching and altered river flows with obvious impacts on fisherfolk, but it is not just about what happens to the fish," said Dr Daw. "Fishing communities are vulnerable to sea level rise and their livelihoods are threatened by storms and extreme weather. Meanwhile, the social and economic context of fisheries will be disrupted by impacts on security, migration, transport and markets."

"Fisheries are already rapidly evolving due to overexploitation and globalisation. They will suffer from wide range of different impacts from climate change, which may be unpredictable and surprising. The poorest will be least able to adapt to these impacts. For example in Kenya poorer fishers were shown to be less likely to switch to other livelihoods if catches declined."

Prof Adger added: "Climate change is going to be a huge challenge to every sector of society and what we're learning about fisheries shows how difficult adaptation will be, particularly for the poorest parts of the world."

According to the report, marine capture fisheries already facing multiple challenges due to overfishing, habitat loss and weak management are poorly positioned to cope with new problems stemming from climate change. Small island developing states -- which depend on fisheries and aquaculture for at least 50 percent of their animal protein intake -- are in a particularly vulnerable position.

Some 520 million people depend on fisheries and aquaculture as a source of protein and income. For 400 million of the poorest of these, fish provides half or more of their animal protein and dietary minerals. Many fishing and coastal communities already subsist in precarious and vulnerable conditions because of poverty and rural underdevelopment, with their wellbeing often undermined by over-exploitation of fishery resources and degraded ecosystems.

Inland fisheries -- 90 per cent of which are found in Africa and Asia -- are also at risk, threatening the food supply and livelihoods of some of the world's poorest populations. Warming in Africa and central Asia is expected to be above the global mean, and predictions suggest that by 2100 significant negative impacts will be felt across 25 per cent of Africa's inland aquatic ecosystems.

Fish farming will also be affected. Nearly 65 per cent of aquaculture is inland and concentrated mostly in the tropical and subtropical regions of Asia, often in the delta areas of major rivers at the mid- to upper levels of tidal ranges. Sea level rise over the next decades will increase upstream salinity, affecting fish farms.

A crucial issue highlighted by the report relates to how well such communities will be able to adapt to change. For example, even if African coastal fisheries do not face huge impacts, the region's 'adaptive capacity' to respond to climate change is low, rendering communities there highly vulnerable even to minor changes in climate and temperature.

Friendly Bacteria Love the Humble Apple

Microbiologists from the National Food Institute at the University of Denmark fed rats on a diet that was rich in whole apples, apple juice, purée or pomace, or put them on a control diet. They then analysed the microbial content of the rats' digestive systems to see if eating apples had any impact on the numbers of presumed 'friendly' bacteria in the gut.
"Certain bacteria are believed to be beneficial for digestive health and may influence the risk for cancer. We faced a well-known problem though -- many types of bacteria cannot be easily cultured in the lab," said research leader Professor Tine Rask Licht. The team therefore used genetics instead of culture techniques to examine the microbiology of the intestines. 16S rRNA is a molecule that is only found in bacteria and its make up is unique to each species or strain. "By working out the sequences of 16S rRNA molecules in the rats' intestines and matching these to known bacterial profiles of 16S rRNA, we could determine which microorganisms were abundant in each group of rats," explained Licht.
So what was the verdict? "In our study we found that rats eating a diet high in pectin, a component of dietary fiber in apples, had increased amounts of certain bacteria that may improve intestinal health," said co-researcher Andrea Wilcks. "It seems that when apples are eaten regularly and over a prolonged period of time, these bacteria help produce short-chain fatty acids that provide ideal pH conditions for ensuring a beneficial balance of microorganisms. They also produce a chemical called butyrate, which is an important fuel for the cells of the intestinal wall."
Of course, further research is needed to determine whether the digestive system of humans responds to apples in the same way as rats, but these findings certainly suggest that Europe's favourite fruit has a well-deserved place in our 5-a-day.

Terror Is Us.....

They came down,vaguely three times
Individuals, not society
We have lasted long
They not at all
Terrorists?
Terror is us

More lives lost there
Less lives lost here
Higher religion here?
Lower religion there?
Makes no sense for us
To attack a party from the east
When they have barely harmed
Terrorists?
Terror is us

They improved the w...orld
We improve the world?
They are evil?
We are evil
They are weak
We are strong for attacking?
Terrorists?
Terror is us

A great empire fell
A group stood and took the enemy across the sea down
An entire nation did not do such
Nor did a religion
Terrorists?
Terror is us