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Wednesday, April 3, 2013

Total buzz kill: Metals in flowers may play role in bumblebee decline

Apr. 2, 2013 ? Beekeepers and researchers nationally are reporting growing evidence that a powerful new class of pesticides may be killing off bumblebees. Now, research at the University of Pittsburgh points toward another potential cause: metal pollution from aluminum and nickel.

Published in the journal Environmental Pollution, the Pitt study finds that bumblebees are at risk of ingesting toxic amounts of metals like aluminum and nickel found in flowers growing in soil that has been contaminated by exhaust from vehicles, industrial machinery, and farming equipment. The Pitt study finds that bumblebees have the ability to taste -- and later ignore -- certain metals such as nickel, but can do so only after they visit a contaminated flower. Therefore, the insects are exposed to toxins before they even sense the presence of metals.

"Although many metals are required by living organisms in small amounts, they can be toxic to both plants and animals when found in moderate to high concentrations," said Tia-Lynn Ashman, principal investigator of the study and professor and associate chair in Pitt's Department of Biological Sciences in the Kenneth P. Dietrich School of Arts and Sciences. "Beyond leading to mortality, these metals can interfere with insect taste perception, agility, and working memory -- all necessary attributes for busy bumblebee workers."

Ashman and George Meindl, coauthor of the study and a PhD candidate in Ashman's lab, studied bumblebee behavior using the Impatiens capensis, a North American flower that blooms in summer. Its flowers are large, producing a high volume of sugar-rich nectar each day -- an ideal place for bumblebees to forage. The blooms were collected from the field each morning of the two-week study and were of a similar age, color, and size.

To determine whether nickel and aluminum in the flowers' nectar influenced bumblebee behavior, Ashman and Meindl used two groups of uncontaminated flowers, one group of flowers contaminated by nickel, and another contaminated by aluminum. When a bumblebee visited a flower in an array, the entire visitation was recorded as well as the time spent (in seconds) foraging on each individual flower. This included monitoring whether the bee moved from a contaminated to a noncontaminated flower, whether the bee moved to the same group it had just sampled, or whether the bee left the flower group without visiting other individual blooms. Following each observed visit, all flowers in the array were replaced with new flowers, to ensure accurate results.

"We found that the bees still visited those flowers contaminated by metal, indicating that they can't detect metal from afar," said Ashman. "However, once bumblebees arrive at flowers and sample the nectar, they are able to discriminate against certain metals."

In the study, the bees were able to taste, discriminate against, and leave flowers containing nickel. However, this was not the case for the aluminum-treated flowers, as the bees foraged on the contaminated flowers for time periods equal to those of the noncontaminated flowers.

"It's unclear why the bees didn't sense the aluminum," said Meindl. "However, past studies show that the concentrations of aluminum found throughout blooms tend to be higher than concentrations of nickel. This suggests that the bees may be more tolerant or immune to its presence."

These results also have implications for environmentally friendly efforts to decontaminate soil, in particular a method called phytoremediation -- a promising approach that involves growing metal-accumulating plants on polluted soil to remove such contaminates. Ashman says this approach should be considered with caution because the bees observed in the study foraged on metal-rich flowers. She states that further research is needed to identify plants that are ecologically safe and won't pose threats to local animals that pollinate.

The paper, "The effects of aluminum and nickel in nectar on the foraging behavior of bumblebees" first appeared online March 6 in Environmental Pollution. Funding was provided by the Carnegie Museum of Natural History's Powdermill Nature Reserve in Rector, Pa., a Botany-In-Action Fellowship from the Phipps Botanical Garden and Conservatory in Pittsburgh, an Ivey McManus Predoctoral Fellowship to Meindl, and a National Science Foundation grant (DEB 1020523) to Ashman. The bees were observed at a nature reserve in Western Pennsylvania during August and September 2012.

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The above story is reprinted from materials provided by University of Pittsburgh.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.

Journal Reference:

George A. Meindl, Tia-Lynn Ashman. The effects of aluminum and nickel in nectar on the foraging behavior of bumblebees. Environmental Pollution, 2013; 177: 78 DOI: 10.1016/j.envpol.2013.02.017

Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.

Source: http://feeds.sciencedaily.com/~r/sciencedaily/strange_science/~3/AegmMOcRNhc/130402152432.htm

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Tuesday, April 2, 2013

Palestinian Hamas Islamists re-elect Meshaal as leader

By Nidal al-Mughrabi

GAZA (Reuters) - The Islamist Palestinian Hamas group re-elected the relatively pragmatic Khaled Meshaal as its leader on Tuesday despite past criticism of him by hardliners in the Hamas-ruled Gaza Strip.

A diplomat in the region said Egypt and Qatar had lobbied strongly on behalf of a reluctant Meshaal before the vote in Cairo by about 60 Hamas leaders who had met through the night.

Born in the Israeli-occupied West Bank, Meshaal, 56, has lived in exile for decades and, like his Hamas comrades, rejects Israel's right to exist. But he played a vital role in indirect, Egyptian-mediated talks between Israel and Hamas to secure a ceasefire that ended an eight-day Gaza war four months ago.

And Meshaal drew criticism last year from Hamas's Gaza-based leadership over what some officials saw as a personal initiative to heal a rift with Western-backed Palestinian President Mahmoud Abbas. His rival Fatah party lost control of the Israeli-blockaded enclave to Hamas in a brief civil war in 2007.

In a statement announcing Meshaal's re-election, Hamas said its highest decision-making body, the Shoura Council, had "renewed its trust in the political office headed by brother Khaled Meshaal".

The diplomat in the region, who asked not to be identified, said Egypt's Islamist leadership and the wealthy Gulf emirate of Qatar had backed Meshaal, who had earlier promised to step down.

"They saw Meshaal as a moderate and an example of a leader who saw the world more comprehensively than other (Gaza-based) hardliners in the group," said the diplomat.

Meshaal left Damascus, where Hamas had a headquarters, about a year ago after the Sunni Islamist militant movement broke with President Bashar al-Assad over the civil war in Syria.

In December, Meshaal traveled from Egypt to make his first visit to Gaza, where he told a rally he would never recognize Israel and pledged to "free the land of Palestine inch by inch".

PARIAH

Once treated as a pariah by many U.S.-allied Arab leaders, Hamas has seen its standing in the region rise on the back of Arab uprisings that have ushered in more sympathetic Islamist governments in Egypt and elsewhere.

Israel, the United States and most Western governments view Hamas as a terrorist group for its refusal to recognize the Jewish state or to renounce violence that included suicide bombings in a Palestinian uprising a decade ago.

"I do not say Europe is going to open up to Hamas tomorrow," said the diplomat. But he added that a "real engagement with the West" was possible if Meshaal persuaded Islamist colleagues to change their policies.

Palestinian political analyst Hani al-Masri said Meshaal's re-election signaled that Hamas was showing a desire for more moderation in order to build bridges with the West, but "it did not mean that Meshaal was a man who raises a white flag".

Meshaal burnished his credentials within Hamas after surviving an Israeli assassination attempt in Jordan in 1997. He succeeded the group's founder, Sheikh Ahmed Yassin, in 2004 after Israel assassinated the wheelchair-bound cleric.

Hamas, which has close links to Egypt's Muslim Brotherhood, was founded in 1988 soon after Palestinians launched an uprising against Israel. Yassin was killed during a second revolt.

Despite falling out with Syria, Meshaal has sought to maintain ties with Iran, an Assad ally that supplies weapons to Hamas, including rockets the group has fired at Israeli cities.

Israel has struck repeatedly at militants in Gaza, attacks that have sometimes caused heavy casualties among civilians in the impoverished, densely-populated coastal territory.

Meshaal, who now divides his time between Cairo and Qatar, has tried to overcome his differences with Abbas, who supports a two-state solution to the Israeli-Palestinian conflict.

His re-election, according to senior Fatah official Mahmoud al-Aloul, "may boost chances of reconciliation (with Abbas), but that does not mean it would be done, given remaining disputes within Hamas".

(Reporting by Nidal al-Mughrabi, Additional reporting by Ali Sawafta in Ramallah, Ahmed Jadallah Salem in Dubai, Editing by Jeffrey Heller and Mark Heinrich)

Source: http://news.yahoo.com/palestinian-islamist-group-hamas-elects-meshaal-leader-022102548.html

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'Glee' Star Cory Monteith In Rehab For Substance Addiction

Actor gets support from co-star and girlfriend Lea Michele.
By Gil Kaufman

Cory Monteith
Photo: Getty Images

Source: http://www.mtv.com/news/articles/1704660/cory-monteith-rehab.jhtml

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Firefox 20 Launches With Improved Private Browsing, New Download Manager And More WebRTC And HTML5 Features

Firefox 20 is now available for download. The emphasis of today’s release is on Firefox’s?private browsing mode, which now allows Firefox desktop users to open a private browsing session without the need to shut down the whole browser, while Firefox for Android users can use per-tab private browsing. Also new in this version is a download manager for the desktop, the ability to customize the shortcuts on the home screen with your favorite sites and support for additional HTML5 and WebRTC features. The new version of Firefox for Android now also supports more devices that use less powerful ARMv6 processors, including the Samsung Galaxy Next, Dart, Pop and Q, as well as the HTC Aria and Legend. The new porn per-tab private browsing mode, Mozilla writes in today’s announcement, lets you “shop for a birthday gift in a private window with your existing browsing session uninterrupted. You can also use a private browsing window to check multiple email accounts simultaneously.” The feature that users will probably notice first, however, is the new download experience. Here is what it looks like: For developers, this new version introduces support for WebRTC’s getUserMedia call, which allows developers to access a user’s camera or microphone (with permission, of course). Firefox 20 also now supports blend modes?for the <canvas> element and a number of <audio> and <video> improvements.

Source: http://feedproxy.google.com/~r/Techcrunch/~3/BACq-WxggIc/

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Monday, April 1, 2013

Lesser-Known Strain of Bird Flu Kills 2 in China

[unable to retrieve full-text content]The authorities said the two Shanghai men, 27 and 87 years old, fell ill after contracting the H7N9 strain in February and died in March.