MH370 crash: experts in France begin examination of Boeing 777 flaperon

Identification of aircraft part that washed up on Réunion island last week could be first clue to fate and whereabouts of missing Malaysia Airlines flight

Technical experts in France will on Wednesday begin examining a plane part that almost certainly belonged to missing flight MH370, raising hopes that some light may finally be shed on one of aviation’s darkest mysteries.

Related: MH370 search: what is the 'flaperon' debris found in Réunion?

Continue reading...

Related posts:

  1. Confidence grows that plane wreckage is from MH370
  2. MH370: aircraft debris flown to France for analysis
  3. Suspected wing of MH370 arrives in France for tests
Posted in Asia Pacific, Australia news, China, Europe, France, Malaysia, Malaysia Airlines flight MH370, Réunion, World news | Comments Off

Heating and cooling genetic samples with light leads to ultrafast DNA diagnostics

An artist’s rendering of photonic PCR on a chip using light to rapidly heat and cool electrons at the surface of a thin film of gold. This method yields gene amplification results in mere minutes, and promises to transform point-of-care diagnostics in fields as diverse as medicine, food security and evolutionary biology. (credit: Luke Lee’s BioPOETS lab)

New technology developed by bioengineers at the University of California, Berkeley, promises to dramatically speed up the polymerase chain reaction (PCR) DNA test and make it cheaper and more portable by simply accelerating the heating and cooling of genetic samples with the switch of a light.

This turbocharged thermal cycling, described in an open-access paper published Friday July 31 in the journal Light: Science & Application, greatly expands the clinical and research applications of the PCR test, with results in minutes instead of an hour or more.

The PCR test, which amplifies a single copy of a DNA sequence to produce thousands to millions of copies, has become vital in genomics applications, ranging from cloning research to forensic analysis to paternity tests. PCR is used in the early diagnosis of hereditary and infectious diseases, and even for analysis of ancient DNA samples of mummies and mammoths.

The huge impact of the PCR test in modern science was recognized in 1993 with a Nobel Prize in Chemistry for its inventors, Kary Mullis and Michael Smith.

Using light-emitting diodes (LEDs), the UC Berkeley researchers were able to heat electrons at the interface of thin films of gold and a DNA solution. They clocked the speed of heating the solution at around 55 degrees Fahrenheit per second. The rate of cooling was equally impressive, coming in at about 43.9 degrees per second.

The heating-time bottleneck

“PCR is powerful, and it is widely used in many fields, but existing PCR systems are relatively slow,” said study senior author Luke Lee, a professor of bioengineering. “It is usually done in a lab because the conventional heater used for this test requires a lot of power and is expensive. Because it takes an hour or longer to complete each test, it is not practical for use for point-of-care diagnostics. Our system can generate results within minutes.”

Schematic showing the ultrafast photonic PCR using LED lights under a thin gold film to amplify genetic samples. The repeated heating and cooling process, called thermal cycling, is needed to separate the double-stranded DNA (1-Denaturation). Complementary bases from a primer then bind to the single strand (2-Annealing and extension), resulting in two copies of the gene. The process is repeated for at least 30 cycles. (credit: Jun Ho Son, UC Berkeley)

The slowdown in conventional PCR tests comes from the time it takes to heat and cool the DNA solution. The PCR test requires repeated temperature changes — an average of 30 thermal cycles at three different temperatures — to amplify the genetic sequence. This process involves breaking up the double-stranded DNA and binding the single strand with a matching primer. With each heating-cooling cycle, the amount of the DNA sample is doubled.

To speed up this thermal cycling, Lee and his team of researchers took advantage of plasmonics, or the interaction between light and free electrons on a metal’s surface. When exposed to light, the free electrons get excited and begin to oscillate, generating heat. Once the light is off, the oscillations and the heating stop.

Gold, it turns out, is a popular metal for this plasmonic photothermal heating because it is so efficient at absorbing light. It has the added benefit of being inert to biological systems, so it can be used in biomedical applications.

For their experiments, the researchers used thin films of gold that were 120 nanometers thick, or about the width of a rabies virus. The gold was deposited onto a plastic chip with microfluidic wells to hold the PCR mixture with the DNA sample.

The light source was an array of off-the-shelf LEDs positioned beneath the PCR wells. The peak wavelength of the blue LED light was 450 nanometers, tuned to get the most efficient light-to-heat conversion.

The researchers were able to cycle from 131 degrees to 203 degrees Fahrenheit 30 times in less than five minutes.

They tested the ability of the photonic PCR system to amplify a sample of DNA, and found that the results compared well with conventional PCR tests.

“This photonic PCR system is fast, sensitive and low-cost,” said Lee, who is also co-director of the Berkeley Sensor and Actuator Center. “It can be integrated into an ultrafast genomic diagnostic chip, which we are developing for practical use in the field. Because this technology yields point-of-care results, we can use this in a wide range of settings, from rural Africa to a hospital ER.”

Abstract of Ultrafast photonic PCR

Nucleic acid amplification and quantification via polymerase chain reaction (PCR) is one of the most sensitive and powerful tools for clinical laboratories, precision medicine, personalized medicine, agricultural science, forensic science and environmental science. Ultrafast multiplex PCR, characterized by low power consumption, compact size and simple operation, is ideal for timely diagnosis at the point-of-care (POC). Although several fast/ultrafast PCR methods have been proposed, the use of a simple and robust PCR thermal cycler remains challenging for POC testing. Here, we present an ultrafast photonic PCR method using plasmonic photothermal light-to-heat conversion via photon–electron–phonon coupling. We demonstrate an efficient photonic heat converter using a thin gold (Au) film due to its plasmon-assisted high optical absorption (approximately 65% at 450 nm, the peak wavelength of heat source light-emitting diodes (LEDs)). The plasmon-excited Au film is capable of rapidly heating the surrounding solution to over 150 °C within 3 min. Using this method, ultrafast thermal cycling (30 cycles; heating and cooling rate of 12.79±0.93 °C s−1 and 6.6±0.29 °C s−1, respectively) from 55 °C (temperature of annealing) to 95 °C (temperature of denaturation) is accomplished within 5 min. Using photonic PCR thermal cycles, we demonstrate here successful nucleic acid (λ-DNA) amplification. Our simple, robust and low cost approach to ultrafast PCR using an efficient photonic-based heating procedure could be generally integrated into a variety of devices or procedures, including on-chip thermal lysis and heating for isothermal amplifications.

Related posts:

  1. After 30 years, more light is cast on the BBC’s Real Lives drama
  2. Kim Hyo-joo leads Women’s British Open but Donald Trump steals limelight
  3. Sierra Leone: Ebola Death in Sierra Leone Leads to Mass Quarantine
Posted in Biotech, News, World news | Comments Off

A precision brain-controlled prosthesis nearly as good as one-finger typing

Brain-controlled prostheses sample a few hundred neurons to estimate motor commands that involve millions of neurons. So tiny sampling errors can reduce the precision and speed of thought-controlled keypads. A Stanford technique can analyze this sample and quickly make dozens of corrective adjustments to make thought control more precise. (credit: Jonathan Kao, Shenoy Lab)

An interdisciplinary team led by Stanford electrical engineer Krishna Shenoy has developed a technique to improve brain-controlled prostheses. These brain-computer-interface (BCI) devices, for people with neurological disease or spinal cord injury, deliver thought commands to devices such as virtual keypads, bypassing the damaged area.

The new technique addresses a problem with these brain-controlled prostheses: they currently access a sample of only a few hundred neurons, so tiny errors in the sample — neurons that fire too fast or too slow — reduce the precision and speed of thought-controlled keypads.

Understanding brain dynamics for arm movements

In essence the new prostheses analyze the neuron sample and quickly make dozens of corrective adjustments to the estimate of the brain’s electrical pattern.

Shenoy’s team tested a brain-controlled cursor meant to operate a virtual keyboard. The system is intended for people with paralysis and amyotrophic lateral sclerosis (ALS), also called Lou Gehrig’s disease, a condition that Stephen Hawking has. ALS degrades one’s ability to move.

The new corrective technique is based on a recently discovered understanding of how monkeys naturally perform arm movements. The researchers studied animals that were normal in every way. The monkeys used their arms, hands and fingers to reach for targets presented on a video screen. The researchers sought to learn, through hundreds of experiments, what the electrical patterns from the 100- to 200-neuron sample looked like during a normal reach — to understand the “brain dynamics” underlying reaching arm movements.

“These brain dynamics are analogous to rules that characterize the interactions of the millions of neurons that control motions,” said Jonathan Kao, a doctoral student in electrical engineering and first author of the open-access Nature Communications paper on the research. “They enable us to use a tiny sample more precisely.”

A decoding algorithm

In their current experiments, Shenoy’s team members distilled their understanding of brain dynamics into an algorithm that could decode (analyze) the measured electrical signals that their prosthetic device obtained from the sampled neurons. The algorithm tweaked these measured signals so that the sample’s dynamics were more like the baseline brain dynamics and thus more precise.

To test this algorithm, the Stanford researchers first trained two monkeys to choose targets on a simplified keypad. The keypad consisted of several rows and columns of blank circles. When a light flashed on a given circle the monkeys were trained to reach for that circle with their arms.

To set a performance baseline, the researchers measured how many targets the monkeys could tap with their fingers in 30 seconds. The monkeys averaged 29 correct finger taps in 30 seconds.

In the actual experiment, the researchers only scored virtual taps that came from the monkeys’ brain-controlled cursor. Although the monkey may still have moved his fingers, the researchers only counted a hit when the brain-controlled cursor, corrected by the algorithm, sent the virtual cursor to the target.

The prosthetic scored 26 thought-taps in 30 seconds, about 90 percent as quickly as a monkey’s finger. (See video of hand versus thought-controlled cursor taps.)

Thought-controlled keypads are not unique to Shenoy’s lab. Other brain-controlled prosthetics use different techniques to solve the problem of sampling error. But of several alternative techniques tested by the Stanford team, the closest resulted in 23 targets in 30 seconds.

Next steps

The goal of all this research is to get thought-controlled prosthetics to people with ALS. Today these people may use an eye-tracking system to direct cursors or a “head mouse” that tracks the movement of the head. Both are fatiguing to use. Neither provides the natural and intuitive control of readings taken directly from the brain.

“Brain-controlled prostheses will lead to a substantial improvement in quality of life,” Shenoy said. “The speed and accuracy demonstrated in this prosthesis results from years of basic neuroscience research and from combining these scientific discoveries with the principled design of mathematical control algorithms.”

The U.S. Food and Drug Administration recently gave Shenoy’s team the green light to conduct a pilot clinical trial of their thought-controlled cursor on people with spinal cord injuries.

“This is a fundamentally new approach that can be further refined and optimized to give brain-controlled prostheses greater performance, and therefore greater clinical viability,” Shenoy said.

Abstract of Single-trial dynamics of motor cortex and their applications to brain-machine interfaces

Increasing evidence suggests that neural population responses have their own internal drive, or dynamics, that describe how the neural population evolves through time. An important prediction of neural dynamical models is that previously observed neural activity is informative of noisy yet-to-be-observed activity on single-trials, and may thus have a denoising effect. To investigate this prediction, we built and characterized dynamical models of single-trial motor cortical activity. We find these models capture salient dynamical features of the neural population and are informative of future neural activity on single trials. To assess how neural dynamics may beneficially denoise single-trial neural activity, we incorporate neural dynamics into a brain–machine interface (BMI). In online experiments, we find that a neural dynamical BMI achieves substantially higher performance than its non-dynamical counterpart. These results provide evidence that neural dynamics beneficially inform the temporal evolution of neural activity on single trials and may directly impact the performance of BMIs.

Related posts:

  1. The brain’s got rhythm
  2. A simulated robot with bacterial brain
  3. An incredible nanoscale 3-D voyage through a tiny part of the mouse brain
Posted in Cognitive Science/Neuroscience, News, World news | Comments Off

Lee Hee-ho, first lady from South Korean ‘sunshine’ era, visits the North

Government in Seoul says there is no official mission for widow of Kim Dae-jung, president who tried to open up relations on bitterly divided peninsula

Related: North Korea releases video of pastor confessing crimes to congregation

Lee Hee-ho, the widow of late South Korean president Kim Dae-jung, has flown to North Korea, saying she hoped the rare trip would help ease cross-border tensions.

Continue reading...

Related posts:

  1. Two South Korean soldiers injured in apparent landmine explosion on border
  2. No sex, drugs or rock’n’roll – a North Korean gap year
  3. South Korean troops fire warning shots at North Korean soldiers
Posted in Asia Pacific, North Korea, South Korea, World news | Comments Off

India train crash: rising death toll after two express services derail at bridge

Trains going opposite ways run off track at same river crossing in Madhya Pradesh state amid heavy rains and flooding

Multiple deaths were reported and rescue efforts were continuing after two trains derailed within minutes of each other while crossing a river bridge in central India.

One of the trains was on its way to Mumbai when the accident happened in Madhya Pradesh state, while the other was travelling in the opposite direction, the Press Trust of India (PTI) news agency reported.

Continue reading...

Related posts:

  1. Dozens dead as two trains derail over river in India
  2. Yakub Memon: India carries out execution over 1993 bomb attacks
  3. Monsoon rains leave 100 dead in India
Posted in India, South and Central Asia, Train crashes, World news | Comments Off

Gillian Triggs condemns bill to strip dual nationals’ citizenship as ‘broad, vague’

Human rights commissioner tells parliamentary committee that bill ‘strikes at the heart of Australian multiculturalism and our migrant status’

The human rights commissioner has described the bill to strip citizenship from dual nationals as “striking at the heart” of Australian multiculturalism.

Gillian Triggs told the parliamentary joint committee on intelligence and security that Australian dual citizens would want to moderate their behaviour because the language of the bill, which leads to automatic loss of citizenship, was “so vague”.

Continue reading...

Related posts:

  1. Planned Parenthood bill blocked: For GOP, abortion as national issue is tricky
  2. Burundi: Leading Human Rights Defender Shot
  3. Nitrous oxide campaigners take drug outside UK parliament in protest at bill
Posted in Australian politics, Australian security and counter-terrorism, Coalition, Gillian Triggs, Human rights, Law, World news | Comments Off

FBI looking into security of Clinton private email account: Washington Post

WASHINGTON (Reuters) - The FBI has begun looking into the security of Hillary Clinton’s private email setup, contacting in the past week a Denver-based technology firm that helped manage the unusual system, the Washington Post reported on Tuesday, citing two government officials.

Related posts:

  1. House speaker: Hillary Clinton should hand over private email server
  2. Sorry, Hillary Clinton fans: her email errors are definitely newsworthy | Trevor Timm
  3. Royal Mail sees red over spate of post box thefts
Posted in topNews, World news | Comments Off

Andrew Robb denounces Alan Jones’s foreign ownership tirade a ‘racist scare’

Trade minister defends Coalition free trade deals with China, South Korea and Japan as 2GB broadcaster declares ‘they’re going to buy up our farms’

An Abbott government minister has accused the broadcaster Alan Jones of promoting a “racist” scare campaign about foreign ownership of Australian farmland and greater trade links with Asian countries.

In an fiery interview on Radio 2GB on Wednesday, the trade minister, Andrew Robb, sought to defend the government’s trade deals with China, South Korea and Japan and the ongoing Trans-Pacific Partnership (TPP) talks.

Continue reading...

Related posts:

  1. South Korea: Mers virus outbreak is over
  2. Andrew Wilkie calls for fraud inquiry into Bishop’s $6,000 plane trip
  3. Kim Jong-Un declares preparations for war with US and South Korea
Posted in Alan Jones, Australia news, Australian media, Coalition, International trade, Television & radio, World news | Comments Off

Stain of Hiroshima’s black rain lingers 70 years on

Some Japanese are still battling for recognition that they are Hibakusha, or were affected by atomic bombings.

Related posts:

  1. Hiroshima survivors fight nuclear industry in Brazil – video
  2. Japan wants US government to explain spying on Prime Minister Shinzo Abe
  3. Tony Abbott rejects proposal to hold Indigenous conventions on recognition
Posted in World news | Comments Off

In coal-mining Kentucky, shock and dismay over Clean Power Plan’s new targets

Kentucky was on track to meet an earlier proposed target in the Clean Power Plan. Now the state, which has lost thousands of coal-mining jobs in recent years, plans to fight the final, more stringent rule in the courts.

Related posts:

  1. Obama’s climate plan seeks to slash emissions from power plants
  2. What changes to expect from Obama’s final Clean Power Plan
  3. Zimbabwe: Govt Arm-Twists Diamond Mining Firms
Posted in World news | Comments Off