Study reveals how dogs detect explosives, offers new training recommendations

A new study found dogs react best to the actual explosive, calling into question the use of products designed to mimic the odor of C-4 for training purposes. Credit: Image courtesy of Indiana University-Purdue University Indianapolis School of Science

A research team at Indiana University-Purdue University Indianapolis (IUPUI) has helped determine the science behind how canines locate explosives such as Composition C-4 (a plastic explosive used by the U.S. military). The study found the dogs react best to the actual explosive, calling into question the use of products designed to mimic the odor of C-4 for training purposes. These findings are the culmination of a four-year contract funded by the U.S. Department of Defense (DOD).

"Appropriately, dogs that are trained to find real explosives are going to find real explosives and not much else," said John Goodpaster, Ph.D., associate professor of chemistry and chemical biology and director for the Forensic and Investigative Sciences Program in the School of Science at IUPUI.

The effectiveness of trained detector dogs is well established, but the study sought to determine which chemical compounds cause a dog to recognize a particular explosive and alert to it. Previous studies have suggested that certain non-explosive chemicals emitted by Composition C-4 cause dogs to alert, and that these specific chemicals could be used as mimic substances to train the dogs in place of real explosives.

In the first phase of the study, IUPUI researchers discovered that the non-explosive chemicals given off by C-4 mimics also are present in a variety of everyday plastic objects. Objects tested included PVC pipes, electrical tape, movie tickets, a plastic grocery bag and plastic food wrapping. Several of the tested items emitted appreciable levels of a mimic compound recommended by some vendors for training canines.

The second phase exposed 33 trained canines from the DOD, Department of Justice, Amtrak and other agencies to these vapors to see if the dogs would respond. The field trials demonstrated that the dogs failed to respond in any significant way to specific odor compounds found in C-4. The results indicate that if the dogs are trained on the full scent, they will only detect real explosives.

"The canines are not easily fooled -- you can't pick and choose components of explosive odors and expect the dog to respond," Goodpaster said. "Dogs are specific and it's the full scent that causes them to alert."

The study also sought to better establish the scientific facts needed for canine detection to be legally admissible evidence -- an effort that found using mimic compounds could present challenges in court. By training with real explosives, false positives are unlikely in the field. Overall, the team recommended that dogs be trained with actual, not mimic, explosives.

While there is technology available to search for explosives, canines remain the best option because of their speed, sensitivity and ability to search large numbers of items, Goodpaster said. Co-authors on the study include current and former IUPUI School of Science undergraduate and graduate students: William Kranz, Kelley Kitts, Nicholas Strange, Joshua Cummins and Erica Lotspeich.

The full study appears in the March 2014 Forensic Science International.

Source: University-Purdue University Indianapolis School of Science

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Glove shows its true colors: Identifies poisons on contact

The sensor glove turns blue in the presence of hazardous substances. Credit: © Fraunhofer EMFT

Security takes top priority in laboratories and in production. In the future, employees exposed to risks will only have to put on a glove in order to receive a toxic substance warning: This textile identifi es poisonous substances, and points them out immediately.

Employees in chemical production, the semiconductor industry or in laboratories are frequently exposed to harmful substances. The problem: Many of these aggressive substances are imperceptible to human senses, which makes handling them so risky. That's why there is a broad range of solutions that employers can use to protect their staff from hazardous substances -- from highly sensitive measuring equipment to heat imaging cameras. Soon, this spectrum will be enhanced by one more clever solution that is easy to handle, and that dispenses with a power supply. Researchers at the Fraunhofer Research Institution for Modular Solid State Technologies EMFT in Regensburg have engineered a glove that recognizes if toxic substances are present in the surrounding air.

The protective glove is equipped with custom-made sensor materials and indicates the presence of toxic substances by changing colors. In this regard, the scientists adapted the materials to the corresponding analytes, and thus, the application. The color change -- from colorless (no toxic substance) to blue (toxic substance detected), for example -- warns the employee immediately. "By synthesizing the adapted color sensor materials, we can detect gases like carbon monoxide, for example, or hydrogen sulfide. Still, this protective gear represents only one potential area of application. Sensor materials could also be deployed for the quick detection of leaks in gas lines," explains Dr. Sabine Trupp, head of the Fraunhofer EMFT Sensor Materials group. The researcher and her team will exhibit this occupational safety article of clothing at Fraunhofer's joint exhibition booth (Hall 12, Booth 537) at the Sensor + Test trade show in Nuremberg from May 14 to 16.

Tailor-made indicator dyes

The warning signal is triggered by an indicator dye integrated into the glove that reacts to the presence of analytes, in this case, the toxic substances. The experts at EMFT used a variety of techniques in order to furnish textiles with sensor-activated dyes. The sensor-activated dyes are applied to the clothing with the customary dye and print process, for example, by affixing them in an immersion bath. Previously, the researchers used targeted chemical modification to adapt the color molecules to the fiber properties of the respective textile. Alternatively, the textiles can also be coated with sensor particles that are furnished with sensor dyes. For this purpose, the scientists integrated the dye molecules either into commercial pigments or they built them up on an entirely synthetic basis. The pigments are then manufactured according to the customary textile finishing process, for instance, the sensor particles are also suitable for silkscreening. "Which version we opt for depends on the requirements of the planned application," says Trupp.

The challenge lies foremost in the tailored development of sensor dyes. "The dye molecule must detect a specific analyte in a targeted manner -- only then will a chemical reaction occur. Moreover, the dye must adhere securely; it cannot disappear due to washing. We aim for the customer's preferences in the color selection as well. All of these aspects must be kept in mind when developing the molecule and pigment properties," explains Trupp.

The expert already has new ideas about how the solution could be developed further. For example, a miniaturized sensor module, integrated into textiles, could record toxic substances, store the measurement data and even transmit them to a main unit. This way, you could document how frequently an individual within a hazardous environment was exposed to poisonous concentrations over a longer period of time.

The researchers also envision other potential applications in the foodstuffs industry: In the future, color indicator systems integrated into foils or bottle closures are intended to make the quality status of the packaged foods visible. Because the sell-by date does not represent a guarantee of any kind. Foodstuffs may often spoil prematurely -- unnoticed by the consumer -- due to a packaging error, or in the warehousing, or due to disruptions in the refrigeration chain. Oil-based and fat-containing products are specifically prone to this, as are meats, fish and ready meals.

Source: Fraunhofer-Gesellschaft

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Easy measurement of the effect of fine dust

The Karlsruhe Exposure System is compact and can measure fine dust concentrations directly at the location of pollution. Credit: VITROCELL Systems GmbH

Fine dusts from industry, traffic, and households are omnipresent. Still, they are difficult to capture by reliable medical measurements. KIT researchers have now developed an exposure system, by means of which biological cells are exposed to fine dust-loaded air flows in an exact and reproducible manner. Using this system, it is possible to collect data on the adverse impact of fine dusts of variable sources in a rapid and inexpensive manner and without animal experiments being needed. In cooperation with the industry partner Vitrocell, a marketable product has been developed.

"Fine dusts may be carbon black from diesel engines, sea salt on the coast, natural dusts, or intermediate products of chemical industry," Dr. Hanns-Rudolf Paur and Sonja Mülhopt of Karlsruhe Institute of Technology explain. All dust grains smaller than 10 µm, i.e. one hundredth of a millimeter, are considered to be fine dust irrespective of their chemical composition. Dust particles smaller than 10 µm easily pass the upper respiratory tract of man. "They deposit in the pulmonary alveoli and may damage the lungs due to their chemical or physical properties."

To study the effects in detail, lung cells and fine dust have to be brought together in a realistic environment. Ultimately, the processes taking place in the human body from the nose to the lungs have to be reproduced. For this purpose, the air containing the fine dust is heated up to body temperature by the Karlsruhe Exposure System. The air flow is provided with about 85% humidity and reduced to the air flow rate of the lungs. For a long-term measurement series, these conditions have to be maintained exactly and reproducibly. Finally, the particle flow passes lung cell cultures cultivated with nutrient medium. 

Depending on the type of fine dust, these cultures subsequently show symptoms of inflammation, oxidation stress, or membrane damage. In parallel, the deposited particle dose is recorded by means of a precision balance.

The new Exposure System is much closer to reality than previous methods that collected fine dust from air or exhaust gas and stirred it into the nutrient liquid. At the same time, the Exposure System works more rapidly for many applications and is cheaper than a study based on animal experiments. Thanks to its compactness, the Karlsruhe Exposure System can also be used for measurements at the place of fine dust development or pollution. "The limitations of conventional methods were overcome by the close, interdisciplinary cooperation of biologists and process engineers at KIT," the Head of the project, Sonja Mülhopt, says. "With the Karlsruhe Exposure System, we now have a technology that will improve the protection of the environment and mankind."

"Research at KIT was the basis of a process with a high industry potential," Tobias Krebs of the company Vitrocell Systems (Waldkirch) says. "Together, we now plan to commercialize this product." The impact of fine dusts plays an important role in fundamental research as well as in many areas of application. According to the EU Directive on Chemicals REACH, chemical industry is obliged to classify its products in various hazard categories. 

Manufacturers of lung medicine, such as asthma sprays, are now enabled to test new substances in a close-to-reality manner. New and old biomass fuels may also be relevant fine dust sources.

Source:  Karlsruhe Institute of Technology

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Uranium exposure, skin cancer: Study may help explain link

Diane Stearns and NAU nursing student, Janice Wilson. Credit: Diane Stearns

After years of delving deep into DNA and researching ways in which metal damage may lead to cancer, a team of researchers is taking a step back to look at the surface where one answer may have been all along.

The varying health risks from exposure to natural uranium are well established, but Diane Stearns, professor of biochemistry at Northern Arizona University, and her team have been trying to determine if there is a link between uranium exposure and skin cancer, stating that skin may have been overlooked in the past.

In a recent article published in the Journal of Applied Toxicology, the NAU team shared results from a study that explored photoactivation of uranium as a means to increase its toxicity and ability to damage DNA.

"Our hypothesis is that if uranium is photoactivated by UV radiation it could be more harmful to skin than either exposure alone," Stearns said.

Through the study, the team found that once uranium was present in the skin, exposure to UV radiation or sunlight could be chemically toxic and lead to cancerous lesions. The team members recommend that future risk assessments regarding cancer caused by uranium exposure include the possibility of photoactivation in skin.

They also propose that photoactivated uranium exposure could be even more harmful in cells that can't repair the damage on their own. Stearns explained such cases are found in individuals with Xeroderma Pigmentosum or XP, a disease that causes extreme sensitivity to sunlight.

Through research into the XP cell lines, the team discovered regional relevance for the study. The disease is prevalent on the Navajo Nation, a site of historically high levels of uranium mining and processing in the Southwest.

The 2012 documentary Sun Kissed further piqued the researchers' curiosity. The film cites the incidence of XP in the general population as one in 1 million, yet cases increase significantly to one in 30,000 in the Navajo population.

Stearns believes there may be implications that should be taken into consideration for a population like the Navajo community with carriers of XP mutations and relatively high exposure to uranium and the sun.

"We just want to make people aware that uranium exposure could contribute to skin cancer and could also be exacerbating XP," Stearns said.

Stearns said as she looks to the future, she hopes to fine-tune her understanding of the photoactivation mechanism and how it is damaging DNA. "We have predicted the link but now we would like to study it step by step to establish an even stronger connection."

Together with her Navajo students at NAU, she also hopes to determine whether the old uranium mines might explain the increase in cancer and what is being called a sudden emergence of XP on the Navajo Nation.

"I've had several Navajo students come to me because they found out I was doing uranium research and they had a relative who died of cancer and always wondered if it was uranium," Stearns said. "It's been a really personal way for them to see the value in scientific research because it can directly relate to their community."

Source: Northern Arizona University

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Radiation exposure linked to aggressive thyroid cancers, researchers confirm for the first time

fukushima disaster

For the first time, researchers have found that exposure to radioactive iodine is associated with more aggressive forms of thyroid cancer, according to a careful study of nearly 12,000 people in Belarus who were exposed when they were children or adolescents to fallout from the 1986 Chernobyl nuclear power plant accident.

Researchers examined thyroid cancers diagnosed up to two decades after the Chernobyl accident and found that higher thyroid radiation doses estimated from measurements taken shortly after the accident were associated with more aggressive tumor features.

"Our group has previously shown that exposures to radioactive iodine significantly increase the risk of thyroid cancer in a dose-dependent manner. The new study shows that radiation exposures are also associated with distinct clinical features that are more aggressive," said the paper's first author, Lydia Zablotska, MD, PhD, associate professor in the Department of Epidemiology and Biostatistics at UC San Francisco (UCSF). The paper will be published online in the journal Cancer.

Zablotska said the findings have implications for those exposed to radioactive iodine fallout from the 2011 nuclear reactor incidents in Fukushima, Japan, after the reactors were damaged by an earthquake-induced tsunami.

"Those exposed as children or adolescents to the fallout are at highest risk and should probably be screened for thyroid cancer regularly, because these cancers are aggressive, and they can spread really fast," Zablotska said. "Clinicians should be aware of the aggressiveness of radiation-associated tumors and closely monitor those at high risk."

Chernobyl studies led by Zablotska also showed for the first time that exposures to the radioactive iodine after the Chernobyl nuclear plant accident are associated with a whole spectrum of thyroid diseases, from benign to malignant. Benign encapsulated tumors of the thyroid gland are called follicular adenomas, and are treated in the same way as thyroid cancer -- by removing the thyroid gland, then giving patients pills to replace the hormones that are lost. Lifelong hormone supplementation treatment is both costly and complicated for patients.

Thyroid cancer is ordinarily rare among children, with less than one new case per million diagnosed each year. Among adults, about 13 new cases will be diagnosed each year for every 100,000 people, according to the Surveillance, Epidemiology and End Results (SEER) Program of the National Cancer Institute (NCI). But in the Belarus cohort, the researchers diagnosed 158 thyroid cancers among 11,664 subjects during three rounds of screening. Those who had received higher radiation doses also were more likely to have solid or diffuse variants of thyroid cancer, as well as to have more aggressive tumor features, such as spread to lymphatic vessels and several simultaneous cancer lesions in the thyroid gland.

Source: University of California, San Francisco (UCSF)

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Should the Japanese give nuclear power another chance?

Japanese  nuclear power

On September 9, 2014, the Japan Times reported an increasing number of suicides coming from the survivors of the March 2011 disaster. In Minami Soma Hospital, which is located 23 km away from the power plant, the number of patients experiencing stress has also increased since the disaster. What's more, many of the survivors are now jobless and therefore facing an uncertain future.

This is not the first time that nuclear power has victimized the Japanese people. In 1945, atomic bombs exploded in Hiroshima and Nagasaki, creating massive fears about nuclear power in the Japanese population. It took 20 years for the public to erase the trauma of these events. It was then -- in the mid 1960s(?) -- that the Fukushima Daiichii Nuclear Power Plant was built.

According to Professor Tetsuo Sawada, Assistant Professor in the Laboratory of Nuclear Reactors at Tokyo University, it took a lot of effort to assure people that nuclear power was safe and beneficial. The first step was a legal step: In 1955, the Japanese government passed a law decreeing that nuclear power could only be used for peaceful purposes.

"But that law was not enough to assure people to accept the establishment of nuclear power," said Prof. Sawada.

He explained that the economy plays an important role in public acceptance of nuclear power. Through the establishment of nuclear power plants, more jobs were created, which boosted the economy of the Fukushima region at that time.

"Before the Fukushima disaster, we could find many pro-nuclear people in the area of nuclear power plants since it gave them money," said Prof. Sawada.

Now, more than forty years have passed and the public's former confidence has evolved into feelings of fear about nuclear power and distrust toward the government.

According to a study conducted by Noriko Iwai from the Japanese General Social Survey Research Center, the Fukushima nuclear accident has heightened people's perception of disaster risks, fears of nuclear accident, and recognition of pollution, and has changed public opinion on nuclear energy policy.
"Distance from nuclear plants and the perception of earthquake risk interactively correlate with opinions on nuclear issues: among people whose evaluation of earthquake risk is low, those who live nearer to the plants are more likely to object to the abolishment of nuclear plants," said Iwai.

This finding is in line with the perception of Sokyu Genyu, a chief priest in Fukujuji temple, Miharu Town, Fukushima Prefecture. As a member of the Reconstruction Design Council in Response to the Great East Japan Earthquake, he argued that both the Fukushima Daiichi and Daini nuclear power plants should be shut down in response to the objection of 80% of Fukushima residents.

However, the Japanese government, local scientists and international authorities have announced that Fukushima is safe. Radiation levels are below 1mSv/y, a number that, according to them, we should not be worried about. But the public do not believe in numbers.

But Genyu was not saying that these numbers are scientifically false. Rather, he argues that the problem lies more in the realm of social psychology. Despite the announcement about low-radiation levels, the Japanese people are still afraid of radiation.

"It is reasonable for local residents in Fukushima to speak out very emotionally. Within three months of the disaster, six people had committed sucide. They were homeless and jobless, " said Genyu.

It is heart-breaking to know that victims of the Fukushima Daiichi nuclear accident died not because of radiation, but instead because of depression. Besides the increasing number of suicides, the number ofpatients suffering from cerebrovascular disease (strokes)has also risen. In Minami-Soma Hospital, the population of stroke patients increased by more than 100% after the disaster.

Local doctors and scientists are now actively educating students in Fukushima, convincing them that the radiation will not affect their health.

Dr. Masaharu Tsubokura, a practicing doctor at Minami-Soma Hospital, has been informing students that Fukushima is safe. But sadly, their responses are mostly negative and full of apathy.

"I think the Fukushima disaster is not about nuclear radiation but is rather a matter of public trust in the technology ," said Dr. Tsubokura.

Dr. Tsubokura has given dosimeters, a device used to measure radiation, to children living in Minami-Soma city. But apparently, this was not enough to eliminate people's fears.

In 2012, Professor Ryogo Hayano, a physicist from the University of Tokyo, joined Dr. Tsubokura in Minami-Soma Hospital and invented BABYSCAN technology, a whole-body scanning to measure radiation in small children as well as to allay the fears of Fukushima parents.

"BABYSCAN is unnecessary but necessary. It is unnecessary because we know that the radiation is low. But it is necessary to assure parents that their children are going to be okay," said Prof. Hayano.
After witnessing the fears of the Fukushima people, Prof. Hayano thinks that nuclear power is no longer appropriate for Japan. He believes that the government should shut down nuclear power plants.

"As a scientist, I know that nuclear power is safe and cheap. But looking at the public's fear in Fukushima, I think it should be phased out," said Prof. Hayano.

But, does the government care about the public when it comes to politics?
It has only been three years since the disaster and Prime Minister Shinzo Abe has been keen to revive the country's nuclear power plants. The operations of more than 50 nuclear power plants in Japan have been suspended because of the Daiichi power plant meltdown.

Last month, Japan's Nuclear Regulation Authority approved the reopening of a power plant in Sendai for 2015.

Source: ResearchSEA

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The Fukushima accident underscores need for U.S. to seek out new information about nuclear plant hazards

Fukushima accident 

A new congressionally mandated report from the National Academy of Sciences concludes that the overarching lesson learned from the 2011 Fukushima Daiichi nuclear accident is that nuclear plant licensees and their regulators must actively seek out and act on new information about hazards with the potential to affect the safety of nuclear plants. The committee that wrote the report examined the causes of the Japan accident and identified findings and recommendations for improving nuclear plant safety and offsite emergency responses to nuclear plant accidents in the U.S.

The accident at the Fukushima Daiichi plant was initiated by the Great East Japan Earthquake and tsunami on March 11, 2011. The earthquake knocked out offsite AC power to the plant, and the tsunami inundated portions of the plant site. Flooding of critical equipment resulted in the extended loss of onsite power with the consequent loss of reactor monitoring, control, and cooling functions in multiple units. Three reactors -- Units 1, 2, and 3 -- sustained severe core damage, and three reactor buildings -- Units 1, 3, and 4 -- were damaged by hydrogen explosions. Offsite releases of radioactive materials contaminated land in Fukushima and several neighboring prefectures, prompting widespread evacuations, distress among the population, large economic losses, and the eventual shutdown of all nuclear power plants in Japan.

Personnel at the Fukushima Daiichi plant responded to the accident with courage and resilience, and their actions likely reduced its severity and the magnitude of offsite radioactive material releases, the committee said. However, several factors relating to the management, design, and operation of the plant prevented plant personnel from achieving greater success and contributed to the overall severity of the accident.

Nuclear plant operators and regulators in the U.S. and other countries are taking useful actions to upgrade nuclear plant systems, operating procedures, and operator training in response to the Fukushima Daiichi accident. As the U.S. nuclear industry and its regulator, the U.S. Nuclear Regulatory Commission (USNRC), implement these actions, the report recommends particular attention to improving the availability, reliability, redundancy, and diversity of specific nuclear plant systems:

·DC power for instrumentation and safety system control

·tools for estimating real-time plant status during loss of power

·reactor heat removal, reactor depressurization, and containment venting systems and protocols

·instrumentation for monitoring critical thermodynamic parameters -- for example temperature and pressure -- in reactors, containments, and spent-fuel pools

·hydrogen monitoring, including monitoring in reactor buildings, and mitigation

·instrumentation for both onsite and offsite radiation and security monitoring

·communications and real-time information systems

To further improve the resilience of U.S. nuclear plants, the report also recommends:
·The U.S. nuclear industry and the USNRC should give specific attention to improving resource availability and operator training, including training for developing and implementing ad hoc responses to deal with unanticipated complexities.

·The U.S. nuclear industry and USNRC should strengthen their capabilities for assessing risks from events that could challenge the design of nuclear plant structures and components and lead to a loss of critical safety functions. Part of this effort should focus on events that have the potential to affect large geographic regions and multiple nuclear plants, including earthquakes, tsunamis and other geographically extensive floods, and geomagnetic disturbances. USNRC should support these efforts by providing guidance on approaches and overseeing rigorous peer review.

·USNRC should further incorporate modern risk concepts into its nuclear safety regulations using these strengthened capabilities.

·USNRC and the U.S. nuclear industry must continuously monitor and maintain a strong safety culture and should examine opportunities to increase the transparency of and communication about their efforts to assess and improve nuclear safety.

Until now, U.S. safety regulations have been based on ensuring plants are designed to withstand certain specified failures or abnormal events, or "design-basis-events"-- such as equipment failures, loss of power, and inability to cool the reactor core -- that could impair critical safety functions. However, four decades of analysis and experience have demonstrated that reactor core-damage risks are dominated by "beyond-design-basis events," the report says. The Fukushima Daiichi, Three Mile Island, and Chernobyl accidents were all initiated by beyond-design-basis events. The committee found that current approaches for regulating nuclear plant safety, which have been based traditionally on deterministic concepts such as the design-basis accident, are clearly inadequate for preventing core-melt accidents and mitigating their consequences. A more complete application of modern risk-assessment principles in licensing and regulation could help address this inadequacy and enhance the overall safety of all nuclear plants, present and future.

The Fukushima Daiichi accident raised the question of whether offsite emergency preparedness in the U.S. would be challenged if a similar-scale event -- involving several concurrent disasters -- occurred here. The committee lacked time and resources to perform an in-depth examination of U.S. preparedness for severe nuclear accidents. The report recommends that the nuclear industry and organizations with emergency management responsibilities assess their preparedness for severe nuclear accidents associated with offsite regional-scale disasters.

Emergency response plans, including plans for communicating with affected populations, should be revised or supplemented to ensure that there are scalable and effective strategies, well-trained personnel, and adequate resources for responding to long-duration accident/disaster scenarios. In addition, industry and emergency management organizations should assess the balance of protective actions -- such as evacuation, sheltering-in-place, and potassium iodide distribution -- for affected offsite populations and revise the guidelines as appropriate. Particular attention should be given to protective actions for children, those who are ill, and the elderly and their caregivers; long-term social, psychological, and economic impacts of sheltering-in-place, evacuation, and/or relocation; and decision making for resettlement of evacuated populations in areas that were contaminated by radioactive material.

Source: National Academy of Sciences

Report: http://www.nap.edu/catalog.php?record_id=18294

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