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Sunday, June 16, 2013
Watch One of Cinema's Wildest Drug Trips in a Minute of Crazy Animation
Pope taps trusted prelate to oversee Vatican bank
VATICAN CITY (AP) -- Pope Francis took a first big step in reforming the troubled Vatican bank on Saturday by tapping a trusted prelate to help oversee its management, in a sign he wants to know more about its activities.
Francis signed off on naming Monsignor Battista Ricca as interim prelate of the Institute for Religious Works.
It's a key job that has been left vacant since 2011: The prelate oversees the bank's activities, attends its board meetings and, critically, has access to all its documentation. The prelate reports to the commission of cardinals who run the bank and is currently headed by the Vatican No. 2. That gives Ricca a near-direct line to the pope, serving as a bridge between the bank's lay managers and board members and its cardinal leadership.
Ricca is currently director of the Vatican hotel where Francis lives and other Vatican-owned residential institutes for clergy.
Technically the appointment was made by the bank's five-member commission of cardinals, headed by Cardinal Tarcisio Bertone, Vatican secretary of state. But the Vatican statement announcing the appointment made clear Francis had approved it, an indication that it was something Francis either initiated himself or strongly supported.
The Vatican spokesman, the Rev. Federico Lombardi, said the interim nature of the appointment was a sign that Francis is still mulling how to reform the Vatican bureaucracy as a whole ? one of the major priorities set out by the cardinals who elected him pope in March.
Right before resigning, Benedict XVI named German aristocrat and financier Ernst von Freyberg as IOR president, filling a vacancy that had been left open for nine months following the remarkable ouster of Italian banker Ettore Gotti Tedeschi for alleged incompetence. Von Freyberg has said the bank's main problem is its reputation, not any operational shortcomings.
The Council of Europe's Moneyval committee, however, says otherwise. The committee, which helps member countries comply with international norms to fight money laundering and terrorist financing, gave the Vatican bank several poor or failing grades in its inaugural evaluation last year.
While praising the Vatican as a whole for making progress quickly, Moneyval said the bank's rules for customer due diligence, wire transfers and suspicious transaction reporting were insufficient. It said the bank needed an independent supervisor and must conduct a thorough risk assessment to ensure that it knew its clients and the risks it faces.
Vatican officials have recently revealed that six such transactions were flagged last year and another seven so far in 2013.
But the customer checks are only now getting underway, even though the Vatican pledged to Moneyval that they would be completed by December 2012. Von Freyberg has said they would be completed by the end of July.
The Vatican must submit a progress report to Moneyval in November.
The Vatican opened itself to the Moneyval evaluation process after signing a new European Union monetary agreement in 2009. Its aim is to shed the bank's image as a secretive tax haven and improve its reputation in global financial circles following a series of scandals, including a money-laundering investigation launched by Rome prosecutors in 2010.
In an interview this week, von Freyberg said his aim was to make the bank's activities more transparent, by publishing its annual report online on Oct. 1. He has hired a leading firm in the fight against money laundering, Promontory Group, to go over the bank's client base, a top-notch international law firm to review the bank's legal framework, and a fancy German public relations agency to help revamp the bank's image.
"I cannot comment on the past," von Freyberg said. "I am here now to take things in hand and we are doing this with great effort."
He said he had some of his own ideas about bank reform, but that the cardinals were the top decision-makers and that the mission of the IOR remained the same.
The Vatican bank was founded in 1942 by Pope Pius XII to manage assets destined for religious or charitable works. Located in a tower just inside the gates of Vatican City, it also manages the pension system for the Vatican's thousands of employees.
The bank is not open to the public; its 19,000 clients include Holy See personnel, religious orders, prelates and diplomats accredited to the Holy See.
The Vatican bank's finances have long been shrouded in secrecy. Most famously, it was implicated in a scandal over the collapse of Italy's Banco Ambrosiano in the 1980s in one of Italy's largest fraud cases. Roberto Calvi, the head of Banco Ambrosiano, was found hanging from Blackfriars Bridge in London in 1982 in circumstances that remain mysterious.
Banco Ambrosiano collapsed following the disappearance of $1.3 billion in loans the bank had made to several dummy companies in Latin America. The Vatican had provided letters of credit for the loans.
While denying any wrongdoing, the Vatican bank agreed to pay $250 million to Ambrosiano's creditors.
In the 2010 money laundering case, Italian financial police seized euro23 million and Rome prosecutors placed the IOR's then-president, Gotti Tedeschi, and general director Paolo Cipriani under investigation for alleged violations of Italy's anti-money laundering norms in conducting a routine transaction from an IOR account at an Italian bank. The money was eventually unfrozen. The men technically remain under investigation but nearly three years on, haven't been charged.
But that isn't the only problem facing the IOR. Last year, under pressure from the Bank of Italy, JPMorgan closed its IOR accounts. And in December, again under pressure from the Bank of Italy, Deutsche Bank Italia halted its 15-year term providing electronic payment services to the Vatican, leaving the tiny city state cash-only. E-commerce operations only resumed at the end of May and still aren't fully operational, even though the Vatican announced in Februrary the problem had been resolved, The Associated Press reported earlier this week.
_____
Follow Nicole Winfield at www.twitter.com/nwinfield
Source: http://news.yahoo.com/pope-taps-trusted-prelate-oversee-110932832.html
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Court ruling: a boost for renewables or can of worms?
Appeals court ruling will allow wind energy from the northern Plains to reach population centers in the Midwest. But the ruling may force states to rewrite their renewable portfolio standards, opening them up to attack. ??
President Obama speaks to media at a family farm in Haverhill, Iowa, in 2012 as wind turbines turn in the distance. A court has upheld a federal plan to apportion the cost of transmission lines so that wind energy can flow from sparsely populated areas of Iowa to more populated region of the Midwest.
Carolyn Kaster/AP/File
EnlargeLast week the 7th?Circuit Court of Appeals upheld a FERC plan to apportion costs of new transmission, designed primarily to carry wind from the sparsely populated parts of Minnesota, Iowa and the Dakotas into more populated parts of the MISO region, by spreading the cost of the transmission across ratepayers in the populated regions where the power would be delivered. The decision has been hailed as a victory for renewable energy. FERC's ability to structure recovery from a broad pool of ratepayers to support new transmission capacity for prime renewable development sites that have been undeveloped because they were too remote from existing transmission capacity will create opportunities for many new large scale wind, solar and geothermal developments. ??
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The ruling was challenged by utilities and regulators in Illinois and Michigan on the basis that each state had its own renewable energy mandate and within that mandate there was a preference to meet goals with in-state renewable generation. The argument followed that by forcing its ratepayers to carry these transmission costs FERC was effectively forcing the use of out of state renewable power. The key to the Court's decision was that it viewed the in-state limits as violating the Commerce Clause. In its simplest form the Commerce Clause ensures fairness in interstate commerce and in this case the in-state preference was viewed as creating an unfair advantage for in-state produced power over out-of-state produced power.
The potential ramifications of this decision on renewable portfolio standards (RPS) are significant. Most state RPS programs are structured with a bias for in-state renewable power production, and many (if not all) of these out-of-state restrictions may now be unenforceable.
Tuesday, June 11, 2013
Mysterious monument found beneath the Sea of Galilee
June 10, 2013 ? The shores of the Sea of Galilee, located in the North of Israel, are home to a number of significant archaeological sites. Now researchers from Tel Aviv University have found an ancient structure deep beneath the waves as well.
Researchers stumbled upon a cone-shaped monument, approximately 230 feet in diameter, 39 feet high, and weighing an estimated 60,000 tons, while conducting a geophysical survey on the southern Sea of Galilee, reports Prof. Shmulik Marco of TAU's Department of Geophysics and Planetary Sciences. The team also included TAU Profs. Zvi Ben-Avraham and Moshe Reshef, and TAU alumni Dr. Gideon Tibor of the Oceanographic and Limnological Research Institute.
Initial findings indicate that the structure was built on dry land approximately 6,000 years ago, and later submerged under the water. Prof. Marco calls it an impressive feat, noting that the stones, which comprise the structure, were probably brought from more than a mile away and arranged according to a specific construction plan.
Dr. Yitzhak Paz of the Antiquities Authority and Ben-Gurion University says that the site, which was recently detailed in the International Journal of Nautical Archaeology, resembles early burial sites in Europe and was likely built in the early Bronze Age. He believes that there may be a connection to the nearby ancient city of Beit Yerah, the largest and most fortified city in the area.
Ancient structure revealed by sonar
The team of researchers initially set out to uncover the origins of alluvium pebbles found in this area of the Sea of Galilee, which they believe were deposited by the ancient Yavniel Creek, a precursor to the Jordan River south of the Sea of Galilee. While using sonar technology to survey the bottom of the lake, they observed a massive pile of stones in the midst of the otherwise smooth basin.
Curious about the unusual blip on their sonar, Prof. Marco went diving to learn more. A closer look revealed that the pile was not a random accumulation of stones, but a purposefully-built structure composed of three-foot-long volcanic stones called basalt. Because the closest deposit of the stone is more than a mile away, he believes that they were brought to the site specifically for this structure.
To estimate the age of the structure, researchers turned to the accumulation of sand around its base. Due to a natural build-up of sand throughout the years, the base is now six to ten feet below the bottom of the Sea of Galilee. Taking into account the height of the sand and the rate of accumulation, researchers deduced that the monument is several thousand years old.
Looking deeper
Next, the researchers plan to organize a specialized underwater excavations team to learn more about the origins of the structure, including an investigation of the surface the structure was built on. A hunt for artefacts will help to more accurately date the monument and give clues as to its purpose and builders. And while it is sure to interest archaeologists, Prof. Marco says that the findings could also illuminate the geological history of the region.
"The base of the structure -- which was once on dry land -- is lower than any water level that we know of in the ancient Sea of Galilee. But this doesn't necessarily mean that water levels have been steadily rising," he says. Because the Sea of Galilee is a tectonically active region, the bottom of the lake, and therefore the structure, may have shifted over time. Further investigation is planned to increase the understanding of past tectonic movements, the accumulation of sediment, and the changing water levels throughout history.
Source: http://feeds.sciencedaily.com/~r/sciencedaily/strange_science/~3/YLd8oGJQ2HE/130610113010.htm
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Monday, June 10, 2013
2 out of 3 people face hunger as Haiti woes mount
BELLE ANSE, Haiti (AP) ? The hardship of hunger abounds amid the stone homes and teepee-like huts in the mountains along Haiti's southern coast.
The hair on broomstick-thin children has turned patchy and orangish, their stomachs have ballooned to the size of their heads and many look half their age ? the tell-tale signs of malnutrition.
Mabriole town official Geneus Lissage fears that death is imminent for these children if Haitian authorities and humanitarian workers don't do more to stem the hunger problems.
"They will be counting bodies," Lissage said, "because malnutrition is ravaging children, youngsters and babies."
Three years after an earthquake killed hundreds of thousands and the U.S. promised that Haiti would "build back better," hunger is worse than ever. And despite billions of dollars from around the world pledged toward rebuilding efforts, the country's food problems underscore just how vulnerable its 10 million people remain.
In 1997 some 1.2 million Haitians didn't have enough food to eat. A decade later the number had more than doubled. Today, that figure is 6.7 million, or a staggering 67 percent of the population that goes without food some days, can't afford a balanced diet or has limited access to food, according to surveys by the government's National Coordination of Food Security. As many as 1.5 million of those face malnutrition and other hunger-related problems.
"This is scandalous. This should not be," said Claude Beauboeuf, a Haitian economist and sometime consultant to relief groups. "But I'm not surprised, because some of the people in the slums eat once every two days."
Much of the crisis stems from too little rain, and then too much. A drought last year destroyed key crops, followed by flooding caused by the outer bands of Tropical Storm Isaac and Hurricane Sandy.
Haiti has had similarly destructive storms over the past decade, and scientists say they expect to see more as global climate change provokes severe weather systems.
Klaus Eberwein, general director of the government's Economic and Social Assistance Fund, said: "We are really trying our best. It's not like we're sitting here and not working on it. We have limited resources."
He attributed Haiti's current hunger woes to "decades of bad political decisions" and, more recently, to last year's storms and drought. "Hunger is not new in Haiti," Eberwein said. "You can't address the hunger situation in one year, two years."
In the village of Mabriole, Marie Jean, a 33-year-old mother of six, looked helpless as her naked son Dieufort sat cross-legged in the dirt, a metal spoon in hand that was more toy than tool. The 5-year-old boy barely looked 3, his gaze unfocused and glassy eyes lifeless. His stomach was distended.
Jean said she lost 10 goats and several chickens to Isaac. The goats could have sold for about $17 apiece, the poultry for about $2.80. She could have used the animals for food or the money to hold her over until the new harvest season.
"You depend on this, because it's all you have," Jean said.
Many people have been forced to buy on credit, or look for the cheapest food available while eating smaller and fewer portions. Some families have asked relatives to take care of their children, or handed them over to orphanages so they have one less mouth to feed, humanitarian workers say.
Political decisions already had hurt the ability of Haitian farmers to feed the country. One example: Prodded by the administration of U.S. President Bill Clinton, Haiti cut tariffs on imported U.S. rice, driving many locals out of the market.
Eighty percent of Haiti's rice ? and half of all its food ? is imported now. Three decades ago, Haiti imported only 19 percent of its food and produced enough rice to export. Factories built in the capital at the same time did little to help: They led farmers to abandon their fields in the countryside in hope of higher wages.
At the same time, Haiti has lost almost all of its forest cover as desperately poor Haitians chop down trees to make charcoal. The widespread deforestation does little to contain heavy rainfall or yield crop-producing soil.
With so much depending on imports, meals are becoming less affordable as the value of Haiti's currency depreciates against the U.S. dollar. Haiti's minimum wage is 200 gourdes a day. Late last year, that salary was equivalent to about $4.75; today it's about $4.54 ? a small difference that makes a big strain on the Haitian budget.
One hard-hit area is Gauthier, an arid stretch between the dense capital of Port-au-Prince and the Dominican border a few miles (kilometers) to the east. It's among 44 areas identified by the government as "food insecure," meaning too many tables are bare.
Here, villagers tell of an elusive rainfall that stymied crop production and then the hurricane that followed.
"That is when the misery began," said pastor Estephen Sainvileun, 63, as he sat with friends in the shade of a rare tree.
Hurricane Sandy ravaged the bean crops, leaving a three-month gap until the harvest resumed in December. With no beans to sell, farmers couldn't buy rice, corn or vegetable oil.
"Some people eat by miracle," said Falide Cerve, 51, a part-time merchant and single mother of five.
That has hurt education, too. The Gauthier schoolhouse, with its tin walls and dirt floor, can hold 100 students, but only 43 enrolled. The children are too hungry to learn.
"They're too distracted, and I have to send them home," said Sainvileun, the pastor who runs the tiny schoolhouse.
Especially hurt are children in Haiti's hard-to-reach villages. Directly south of Gauthier is one of the most remote zones in Haiti. The area is one of craggy mountains, the highest in the country at 8,772 feet (2,674 meters). Only the sturdiest off-road vehicles can climb the steep, twisting and rocky roads.
Some villages, such as Anse-a-Boeuf on the southeastern coast, are solely accessible by foot or donkey.
On a recent oven-hot afternoon, a team of Associated Press journalists hiked down a hill, past a thicket of mangroves and into the beachside hamlet. They found several dozen children waddling among the wood huts with the usual signs of malnutrition.
"This child is not malnourished," insisted 45-year-old grandmother Elude Jeudy as she held in her arms 2-year-old Jerydson, naked and crying, too frail to stand a few minutes earlier. "I feed him."
The mother had left the little boy so she could find work in Belle Anse, a nearby village on the ocean.
Neighbor Wilner Fleurimond added: "People shouldn't be living like this."
Villagers say they vote for people they hope will improve their lives but in the end find disappointment.
"We vote for the deputy we know and nothing works," Fleurimond fumed. "We vote for the deputy we don't know and nothing works."
Shortly after taking office, President Michel Martelly launched a nationwide program led by his wife, Sophia, called Aba Grangou, Creole for "end hunger." Financed with $30 million from Venezuela's PetroCaribe fund, the program aims to halve the number of people who are hungry in Haiti by 2016 and eradicate hunger and malnutrition altogether by 2025. Some 2.2 million children are supposed to take part in a school food program financed by the fund.
Eberwein, whose government agency oversees Aba Grangou, said 60,000 mothers have received cash transfers for keeping their children in school. A half million food kits were distributed after Hurricane Sandy, along with 45,000 seed kits to replenish damaged crops, he said. Mid- to long-term solutions require creating jobs.
But the villagers in the Belle Anse area say they've seen scant evidence of the program, as if officials have forgotten the deaths in 2008 of at least 26 severely malnourished children in this very region. That same year, the government collapsed after soaring food prices triggered riots.
USAID has allocated nearly $20 million to international aid groups to focus on food problems since Hurricane Sandy, but villagers in southern Haiti said they have seen little evidence of that.
Despite the discrepancy, one public health expert said there's sufficient proof that at least some of the aid is reaching the population. Were it not, Richard Garfield said, Haiti would see mass migration and unrest.
"Overall aid has gotten to people pretty well. If aid hadn't gotten to people that place would be so much more of a mess," said Garfield, a professor emeritus at Columbia University's Mailman School of Public Health and now a specialist in emergency response at the U.S. Centers for Disease Control and Prevention. "You'd see starvation and riots ... The absence of terrible things is about the best positive thing that we can say."
Government officials concede that not all of the 44 areas have received food kits and other goods as part of the Aba Grangou program.
"It hasn't arrived here yet. It's nothing but rhetoric," said Jean-Marc Tata, a math and French teacher and father of two who lives in Mabriole.
His 18-month-old son's hair began to turn orange after Tropical Storm Isaac knocked down trees, chewed up crops and killed livestock, leaving the family with little to eat.
"We had beans that were ready to pick but everything was lost. This has been a major cause of malnutrition," Tata said in a courtyard ringed with stone homes.
Tata said he had given his son a cup of coffee with a bit of bread, his only meal so far that day as dusk began to fall. The day before: a single bowl of oatmeal.
Haiti in general and the mountain villages in particular have long suffered from chronic hunger. Child malnutrition rates have been high for years. The United Nations' World Food Program reports that nearly a quarter of Haiti's children suffer from malnutrition, though the figure is higher in places such as Guatemala and the Sahel region in Africa.
Isolation doesn't help. A doctor in Belle Anse said his hospital has treated five children who were diagnosed with malnutrition this year. He said more parents would come if they could afford transportation and hospital fees, or take away time from work to make the journey on foot.
"The future is really threatened here," Tata said. "Our life is really threatened here."
___
Associated Press videographer Pierre-Richard Luxama contributed to this report.
___
Trenton Daniel on Twitter: http://twitter.com/trentondaniel.
Source: http://news.yahoo.com/2-3-people-face-hunger-haiti-woes-mount-074207335.html
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CNN trying new weekly nighttime talk show
This Nov. 28, 2008 file photo, George Stroumboulopoulos poses for a photograph after winning best host during the 23rd Annual Gemini Awards in Toronto. It's a safe bet that Stroumboulopoulos will be the first male CNN personality to wear two earrings and a skull ring from the same designer who made one for Keith Richards. Stroumboulopoulos, whose new nighttime talk show premieres Sunday, June 9, 2013 is more curious than dangerous, though. (AP Photo/The Canadian Press, Nathan Denette)
This Nov. 28, 2008 file photo, George Stroumboulopoulos poses for a photograph after winning best host during the 23rd Annual Gemini Awards in Toronto. It's a safe bet that Stroumboulopoulos will be the first male CNN personality to wear two earrings and a skull ring from the same designer who made one for Keith Richards. Stroumboulopoulos, whose new nighttime talk show premieres Sunday, June 9, 2013 is more curious than dangerous, though. (AP Photo/The Canadian Press, Nathan Denette)
NEW YORK (AP) ? It's a safe bet that George Stroumboulopoulos will be the first male CNN personality to wear two earrings and a skull ring from a designer who made one for Keith Richards.
Stroumboulopoulos, whose new nighttime talk show premieres Sunday, is more curious than dangerous, though.
The show gets a solid time slot for its debut, airing after the season finale of Anthony Bourdain's successful "Parts Unknown." Then it will settle into a regular spot on Fridays at 11 p.m. Eastern for the summer and, if things go well, maybe beyond.
It's part of CNN's attempt to branch out beyond news programming at certain times, represented most prominently by Bourdain's show. The effort started before the arrival of new network boss Jeff Zucker ? Stroumboulopoulos had his first contact with the network last summer before Zucker arrived ? but the enthusiasm continued with the change in management.
Stroumboulopoulos (STRAHM'-boo-lahp-yoo-lus) hosts a nightly talk show on the CBC in Canada, where his friendly style seems to encourage celebrities to talk.
"I hope that people pick up something new about the person I'm interviewing and find out a way to relate to them," he said. "I want them to find a connection."
For CNN, the show represents an old style for a new generation. Stroumboulopoulos, 40, said his interest in politics was fueled less by politicians than by listening to the Clash and Public Enemy. He's eager to interview Snoop Lion, the former Snoop Dogg, on his show because he considers him such an important figure in hip-hop.
Rap artist Wiz Khalifa, comic Martin Short and actor Keanu Reeves are the guests on his first show.
Other confirmed interviews for the show's 10-week run include Keanu Reeves, Martin Short, Betty White, Bill Maher, Sharon Stone and filmmaker Werner Herzog. The show will tape before a studio audience in Los Angeles.
Stroumboulopoulos said he's not gunning for the job of CNN's other general interview program, Piers Morgan, and said he likes the way Morgan conducts interviews.
For the moment, he'll fit the CNN show in with a schedule that includes the CBC show (which airs twice in the evening) and a weekly music and talk program he does for a CBS radio station.
"This is what I do," he said. "I don't even have any dependents in my life. I don't even have a plant."
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Wednesday, May 22, 2013
Advance in nanotech gene sequencing technique
Tuesday, May 21, 2013
The allure of personalized medicine has made new, more efficient ways of sequencing genes a top research priority. One promising technique involves reading DNA bases using changes in electrical current as they are threaded through a nanoscopic hole.
Now, a team led by University of Pennsylvania physicists has used solid-state nanopores to differentiate single-stranded DNA molecules containing sequences of a single repeating base.
The study was led by Marija Drndi?, an associate professor in the Department of Physics and Astronomy in the School of Arts and Sciences, along with graduate students Kimberly Venta and Matthew Puster and post-doctoral researchers Gabriel Shemer, Julio A. Rodriguez-Manzo and Adrian Balan. They collaborated with assistant professor Jacob K. Rosenstein of Brown University and professor Kenneth L. Shepard of Columbia University.
Their results were published in the journal ACS Nano.
In this technique, known as DNA translocation measurements, strands of DNA in a salt solution are driven through an opening in a membrane by an applied electric field. As each base of the strand passes through the pore, it blocks some ions from passing through at the same time; amplifiers attached to the nanopore chip can register the resulting drop in electrical current. Because each base has a different size, researchers hope to use this data to infer the order of the bases as the strand passes through. The differences in base sizes are so small, however, that the proportions of both the nanopores and membranes need to be close those of the DNA strands themselves ? a major challenge.
The nanopore devices closest to being a commercially viable option for sequencing are made out of protein pores and lipid bilayers. Such protein pores have desirable proportions, but the lipid bilayer membranes in which they are inserted are akin to a film of soap, which leaves much to be desired in terms of durability and robustness.
Solid-state nanopore devices, which are made of thin solid-state membranes, offer advantages over their biological counterparts ? they can be more easily shipped and integrated with other electronics ? but the basic demonstrations of proof-of-principle sensitivity to different DNA bases have been slower.
"While biological nanopores have shown the ability to resolve single nucleotides, solid-state alternatives have lagged due to two challenges of actually manufacturing the right-sized pores and achieving high-signal, low-noise and high-bandwidth measurements," Drndi? said. "We're attacking those two challenges here."
Because the mechanism by which the nanopore differentiate between one type of base and another is by the amount of the pore's aperture that is blocked, the smaller a pore's diameter, the more accurate it is. For the nanopore to be effective at determining a sequence of bases, its diameter must approach the diameter of the DNA and its thickness must approach that of the space between one base and the next, or about 0.3 nanometers.
To get solid-state nanopores and membranes in these tiny proportions, researchers, including Drndi?'s group, are investigating cutting-edge materials, such as graphene. A single layer of carbon atoms in a hexagonal lattice, graphene membranes can be made a little as about 0.5 nanometers thick but have their own disadvantages to be addressed. For example, the material itself is hydrophobic, making it more difficult to pass strands of DNA through them.
In this experiment, Drndi? and her colleagues worked with a different material ? silicon nitride ? rather than attempting to craft single-atom-thick graphene membranes for nanopores. Treated silicon nitride is hydrophilic and has readily allowed DNA translocations, as measured by many other researchers during the last decade. And while their membrane is thicker, about 5 nanometers, silicon nitride pores can also approach graphene in terms of thinness due to the way they are manufactured.
"The way we make the nanopores in silicon nitride makes them taper off, so that the effective thickness is about a third of the rest of the membrane," Drndi? said.
Drndi? and her colleagues tested their silicon nitride nanopore on homopolymers, or single strands of DNA with sequences that consist of only one base repeated several times. The researchers were able to make distinct measurements for three of the four bases: adenine, cytosine and thymine. They did not attempt to measure guanine as homopolymers made with that base bind back on themselves, making it more difficult to pass them through the nanopores.
"We show that these small pores are sensitive to the base content," Drndi? said, "and we saw these results in pores with diameters between 1 and 2 nanometers, which is actually encouraging because it suggests some manufacturing variability may be okay."
###
University of Pennsylvania: http://www.upenn.edu/pennnews
Thanks to University of Pennsylvania 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/128328/Advance_in_nanotech_gene_sequencing_technique
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