Culture

Improved ship utilization rates and investments in environmentally sustainable technologies for enhanced energy efficiency would significantly reduce carbon dioxide emissions within navigation. A recent study carried out in the Laboratory of Industrial Management at Åbo Akademi University also indicates that such measures would contribute to lowering of freight costs.

The results were obtained by combining emission abatement analysis and investment calculation.

"Through operational and technological measures it is possible to reduce both emissions and freight costs. Moreover, if the same cargo volume can be shipped using less fuel, the shipping companies will gain major savings in terms of fuel costs", explains Research Director Magnus Gustafsson from the Laboratory of Industrial Management at Åbo Akademi University.

The shipping sector generates significant carbon dioxide emissions, which is harmful for both the environment and the society. In recent years, the branch has witnessed both internal willingness and external pressure to reduce emissions, but development has been complicated by the tough competition in shipping.

Digitalisation offers tangible solutions. For instance, new digital planning and booking systems would facilitate smarter use of routes while also diminishing traffic with half-empty vessels or with no cargo onboard.

"By sailing fewer nautical miles with little or no cargo, it is possible to improve the capacity utilization rate and eliminate emissions caused by the so-called ballast traffic", says Henry Schwartz, Doctoral Student in Industrial Management at Åbo Akademi University.

"Our model demonstrated that solar panels, optimized propellers and cold ironing - the possibility to connect to land power network at ports - are among the economically profitable investments in new technologies. In contrast, for example, wind power installations did not appear profitable."

Japan -- Findings from a 700,000-year-old fossil bone indicate that a close relative of the most abundant seabird species in the North Atlantic, the modern dovekie, or 'little auk', used to thrive in the Pacific Ocean and Japan.

Seabirds are top predators in the marine ecosystem, and their distributions are shaped by numerous environmental factors in the ocean. As such, extensive scientific inquiries have been conducted on how seabirds respond to fluctuating oceanic environments in the ecologic and geologic timescales.

"The North Pacific has been one of the most intently investigated regions, but the fossil record of seabirds in the Pleistocene Epoch, about 2.6 to 0.01 million years ago, has been scarce," explains first author Junya Watanabe of Kyoto University's School of Science. "This has led to a frustrating lack of information in this critical time period concerning the origin of modern seabird communities."

In recent years, Watanabe and his team had been investigating seabird fossils from several locations in Chiba and Tokyo prefectures, gaining new insight on the Pleistocene seabird community in the region.

The group had been successful in identifying 17 fossils representing at least 9 species of birds: three species of ducks, a loon, an albatross, a shearwater, a cormorant, an extinct penguin-like seabird called mancalline auk, and a dovekie. Most of these species can be found in the region today; however, the presence of a dovekie was completely unexpected.

Watanabe explains his findings published in Journal of Vertebrate Paleontology.

"At first it confused us that the fossil didn't match any of the Pacific auks, but once we compared it with Atlantic ones, the similarity with the modern dovekie was apparent. It is not clear whether the present fossil is from the same species or a very close cousin, but we are positive it at least comes from the same lineage."

The dovekies we know today are mostly restricted to the North Atlantic and Arctic oceans, with their rare sightings in Japan considered accidental visits. Given the unlikeliness of such accidental visitors to be preserved as fossils, the new findings suggest that dovekies were once fairly common in Japan and the Pacific.

He continues, "Now the question is why dovekies are so rare in the North Pacific today, it's almost paradoxical given their abundance in the North Atlantic. That question remains unexplained, at least until recovery and investigation of further fossil materials."

Interestingly, local decline and extinction events in the past are common in many seabird groups. Deciphering possible causes of such events requires integration of knowledge from various disciplines, including paleontology, paleoclimatology, oceanography and seabird ecology. Watanabe and his team see this as a challenging but rewarding endeavor.

A new analysis of the clinical trials of HPV vaccines to prevent cervical cancer raises doubts about the vaccines' effectiveness. The analysis, published by the Journal of the Royal Society of Medicine, assessed 12 published Phase 2 and 3 randomised controlled efficacy trials of the HPV vaccines Cervarix and Gardasil.

The analysis, carried out by researchers at Newcastle University and Queen Mary University of London, revealed many methodological problems in the design of the Phase 2 and 3 efficacy trials, leading to uncertainty regarding understanding the effectiveness of HPV vaccination.

The researchers found that the trials were not designed to detect cervical cancer, which takes decades to develop. Women in the trials were followed up for six years or less, apart from one trial extension to just under nine years. While the researchers found evidence that vaccination prevents low grade abnormal cell changes, they said this is not clinically important because no treatment is given.

Lead researcher Dr Claire Rees, of Queen Mary University of London, said: "Trials may have overestimated efficacy by combining high-grade cervical disease with low-grade cervical changes that occur more frequently but often resolve spontaneously without progressing. We found insufficient data to clearly conclude that HPV vaccine prevents the higher-grade abnormal cell changes that can eventually develop into cervical cancer."

Dr Rees added: "Abnormal cell changes are likely to have been overdiagnosed in the trials because cervical cytology was conducted at 6-12 months rather than at the normal screening interval of 36 months. This, too, means that the trials may have overestimated the efficacy of the vaccine, again because some of the lesions would have regressed spontaneously."

The researchers also found that the trial populations had limited relevance and validity for real world settings. The women in the trials were older than the target population.

Calling for women to still attend regular cervical screening, co-author of the study, Professor Allyson Pollock, of Newcastle University, said: "We have good evidence that cervical screening significantly reduces the risk of cervical cancer in women regardless of whether they have been vaccinated."

About 800,000 years ago, the giant straight-tusked elephant Palaeoloxodon migrated out of Africa and became widespread across Europe and Asia.

It divided into many species, with distinct types in Japan, Central Asia and Europe -- even some dwarf forms as large as a small donkey on some Mediterranean islands.

In a new study by scientists in Spain, Italy and the UK, including University of Bristol PhD student Hanwen Zhang, published in the journal, Quaternary Science Reviews, some order has been brought into our understanding of all these species.

The most intriguing feature of the straight-tusked elephant, apart from its absolutely enormous size, is the massive, headband-like crest on the skull roof which projects down the forehead. When the celebrated Victorian Scottish geologist Hugh Falconer studied the first fossil skull of Palaeoloxodon found in India, he remarked that the head seemed 'so grotesquely constructed that it looks the caricature of an elephant's head in a periwig'.

For a long time, palaeontologists thought that the European species, Palaeoloxodon antiquus, had a rather slenderly built skull roof crest; whereas the Indian species Palaeoloxodon namadicus, is characterised by an extremely robust skull crest that extends near to the base of the trunk from the top of the skull.

But some Palaeoloxodon skulls, found in Italy and Germany, with almost the same exaggerated skull crest as the Indian form, led a few experts into suspecting these might all be single species.

Hanwen Zhang, who is based in Bristol's School of Earth Sciences, said: "Just like modern elephants, Palaeoloxodon went through six sets of teeth in their lifetimes. This means we can tell the age of any individual with confidence by looking at its fossilised teeth.

"When we looked at a series of skulls from Italy, Germany and India, we found a consistent pattern: the skull crest developed from being very small, not protruding beyond the forehead in juveniles to being larger and more protruding in young adults, eventually becoming very stout in aged adults."

The study's lead author, Asier Larramendi, an independent researcher from Spain, added: "As I plotted various skull and limb bone measurements for these incredible prehistoric elephants, it became clear that the Indian Palaeoloxodon form a distinct group from the European ones; even in European skulls with quite pronounced crests, the skull roof never becomes as thickened as in the Indian specimens.

"This tells us we once had two separate species of these enormous elephants in Europe and India.

"Besides the funky skull roof crest, the head of the straight-tusked elephant is also remarkable for being huge, the largest of any elephant ever - some 4.5 feet from the top of the skull roof to the base of the tusk sheaths!

"Therefore, the skull crest probably evolved to provide additional attachment areas for extra neck muscles, so the animal did not fall on its head."

Hanwen Zhang said: "Having gotten to the bottom of the antiquus/namadicus problem, it then became apparent that other fossil skull materials found in Asia and East Africa represent distinct, possibly more evolutionarily conservative species of Palaeoloxodon.

"Even in fully mature adults with the last set of teeth in place, the skull roof crest remains comparatively unpronounced. This is the case with the earliest Palaeoloxodon from Africa, some Asian species retained this condition."

Researchers from the Faculty of Health and Medical Sciences have shown a possible link between a genetic variation and the widespread type of cardiac arrhythmia, atrial fibrillation.

The scientists conducted the study in zebrafish, which is a recognised scientific animal model within cardiac research.

Here, researchers from the University of Copenhagen in Denmark and the Max Planck Institute in Germany put special focus on the gene pitx2c. The result came as a surprise to them, says Assistant Professor Pia Lundegaard from the Department of Biomedical Sciences.

'It seems that we may also have to think of atrial fibrillation as an atrial cardiomyopathy - that is, a challenged heart - rather than as a purely electrical disorder', she says.

Defects in muscle fibres and mitochondria

Contrary to expectations, the researchers did not find any disturbances in the ion channels that spread electrical signals between the heart's muscle cells.

Instead, they found defects in the structure of the heart muscle itself and in the mitochondria that normally function as the cell's power plant. The defects already occurred in the foetal stage of the fish and deteriorated exponentially with age.

'Usually the structure of a cross-section of the sarcomeres - the muscle fibres - shows a very fine grid structure. But in these fish, it is clear that the structure is disorganised from a very early stage', explains Pia Lundegaard, adding:

'At the same time, we can see in our pictures that there are too many mitochondria. So, it seems that the heart is trying to compensate for the defective muscle fibres. This indicates that there is a structural defect in the heart which over time will cause a rhythm defect'.

Antioxidant prevents defects

According to the research study, the increased number of mitochondria appears to aggravate the negative spiral, the reason being that also the mitochondria are defective and gradually increase the level of so-called oxidative stress.

In other words, they create an unhealthy environment in the cell where different proteins are broken down.

At the same time, however, the researchers found that early and ongoing treatment with the antioxidant NAC seemed to counteract the defect and in the long term prevent atrial fibrillation in the fish.

However, Pia Lundegaard from the Department of Biomedical Sciences emphasises that heart patients should not stockpile antioxidants such as NAC for that reason.

She points out that the studied gene is just one of many possible factors behind atrial fibrillation, which is also greatly influenced by the individual's lifestyle.

In addition, to better demonstrate the effect of the studied gene, the gene defect has been designed to be stronger in the test fish than commonly seen in humans.

Better control procedures

The improved understanding of the disease nevertheless provides greater insight into the reason why some atrial fibrillation medications may not always work as well as one might wish.

Therefore, Pia Lundegaard hopes that the result of the new research will be that more practitioners reconsider the possible causes behind rhythm disorders.

'The rhythm disorder may be secondary to what is actually the problem. We hope that in the future, we can develop better control procedures that will prevent some people's hearts from being worn down for a long time and eventually fail', she says.

The next step for the research group is to investigate other genes associated with atrial fibrillation. Likewise, the group will investigate whether antioxidants other than NAC can prevent the disorder.

IKBFU scientists developed the composition of the capsule shell for the enzyme needed in the treatment of a hereditary disease called "phenylketonuria". Phenylpyrovirogradnaya oligophrenia is a disease that results in degradation of the amino acid called phenylalanine. This amino acid presents in protein-containing food. High levels of phenylalanine can cause problems of mental development throughout life. If diet therapy is not used among children under two, then such violations lead to irreversible deviations in the development of the brain. Increasing the level of phenylalanine in the blood of an adult can reduce the level of mental abilities and reaction speed.

Director of the IKBFU's Institute of Living Systems, Olga Babich told us:

"Today scientists are looking for new ways of treatment of hereditary diseases. Phenylketonuria is one of such diseases, it causes accumulation of toxic products in blood due to the metabolism malfunction in a body which it caused by insufficient amount of phenylalanine amino acid. The frequency of distribution of phenylketonuria among children in the world on average is one out of ten thousand newborns and varies from 1: 200000 to 1: 4370. In Russia, the frequency of phenylketonuria averages 1: 7000. The most common is the classic form of phenylketonuria, in which present-day diet therapy (exclusion of phenylalanine from the diet) is the only effective treatment".

According to the scientist, there are more ways of treating this disease emerging now. For example, one of the ways is enzymotherapy - enzyme treatment. But in Russia those methods are not used due to the lack of available technologies. While the most promising is the use in the treatment of an enzyme called "L-phenylalanine-ammonium lyase", both in the form of injections and capsules/pills, which breaks down phenylalanine to safe products. The therapeutic use of this enzyme is limited by its instability, especially in the acidic environment of the stomach. Therefore, the main challenge for scientists is to develop a stable capsule for the enzyme L-phenylalanine-ammonium lyase.

Olga Babich emphasized:

"As part of this study, a team of scientists developed the capsule shell composition for the L-phenylalanine-ammonium lyase enzyme based on polysaccharides: agar-agar, carrageenan and hydroxypropyl methylcellulose. The effect of different storage temperatures of the enzyme in encapsulated form on its activity was also studied. We found that for all of the proposed capsule formulations, the most suitable storage temperature for the drug is 25 ° C. At capsule storage temperatures of 4 ° C and 30 ° C after 6 months, a significant decrease in enzyme activity was noted, up to 90%. The next stage of research will be devoted to studying the mechanisms of destruction of capsules with L-phenylalanine-ammonium lyase under model conditions close to the conditions of the human gastrointestinal tract, since in the future the developed capsules will be used for replacement therapy of phenylketonuria".

Scientists of Ludwig-Maximilians-Universitaet (LMU) in Munich have developed a tool to eliminate essential proteins from cells with a flash of light. The new method makes it possible to study the function of essential proteins.

Proteins not only provide much of the structural architecture of cells, they also perform most of the executive functions by acting as highly specific chemical catalysts. Hence, they are intimately involved in all fundamental biological processes, including metabolism, growth and cell division. Conversely, alterations in their shapes and activity result in the development of disorders. In order to understand the processes controlled by proteins, it is necessary to understand how each of them works. Biologists normally deduce the role of a protein by analyzing what happens when it is damaged or deleted altogether. Experimentally, this is usually accomplished by mutating or deleting the gene that encodes it. However, in the case of proteins that are essential for the survival of the organism, or of cell types that are required for a particular process, this approach is not very informative, as such mutants tend to die before it can provide insights into the protein's actual function. Researchers led by Professor Heinrich Leonhardt at LMU's Biocenter have now developed a tool that gets around this problem. Their method makes use of either light or specific chemicals to trigger the selective degradation of the protein of interest. The procedure, and a review of the results so far obtained with it, are reported in the journal Nature Communications.

"In order to develop this technology, we reprogrammed the cell's waste-disposal system," says Leonhardt. Proteins that are defective or are no longer required are normally designated for disposal by enzymatically attaching a molecule called ubiquitin to them. The ubiquitin marker is then recognized by a molecular complex called a proteasome, which essentially acts as a shredder of the tagged proteins. The system developed by Leonhardt and his colleagues makes use of small antibodies known as nanobodies to target the protein of interest. The nanobody then brings a specialized ligase for the attachment of the ubiquitin marker - and the target protein is consigned to the proteasome for destruction.

In order to be able to control whether and when a target molecule is labelled and degraded, the scientists have incorporated an additional switch. The target molecule is only marked when the scientists activate this switch with light or small chemical molecules. "In this way, we can regulate the levels of proteins continuously. It's just like using a dimmer, we can set the desired concentration of any given protein and observe the effects on cellular processes," Leonhardt explains.

The LMU researchers first used the system to investigate a protein that plays a critical role in DNA replication. As it is essential for viability it cannot be genetically disabled. "We used the new method to temporarily deplete this protein in cells, and were able to elucidate its involvement in DNA repair," says Wen Deng, lead author of the new study. The results showed that the protein acts as a central scaffold, to load other DNA repair proteins and efficiently fix the DNA damage.

One other advantage of the new tool is that it can be employed in whole organisms. In cooperation with the research group of Professor Barbara Conradt the researchers used the system to study cell death in in the nematode worm Caenorhabditis elegans, which is an established model organism in biology. At certain stages in the development of this worm, one of the two daughter cells produced by specific cell divisions is specifically eliminated. "By depleting the executioner protein with the aid of the new system, we were able to prevent the loss of the corresponding daughter cell and gain insights into the process of programmed cell death," says Leonhardt.

Since the ubiquitin-proteasome system is found not only in all higher organisms, but also in Archaea and even in some bacteria, the team assumes that their approach to the targeted regulation of protein degradation will be broadly applicable. It could therefore make an important contribution to efforts to understand the functions of vital proteins.

Viruses are probably the most peculiar "life forms" known to us, with each species having unique characteristics. One thing common to all viruses is that they attack a "host" cell and hijack its machinery, using it for its own replication. A type of large virus, called "giant virus," has interesting ways of attacking its host organism--an amoeba. Virologists have been trying to understand what makes these viruses so unique for some time now, but to observe them, complex techniques are required. A method called phase-contrast microscopy is commonly used to study all types of cells, including amoebal cells. But, this technique relies heavily on the variation in the conditions of the cell and its background, and sometimes this leads to disruptions in the image produced--for example "halo" (in which the cell is surrounded by a bright light) and "shade-off" (in which the inside of the cell and background are of a similar intensity). This is why, to dig deeper into exactly how giant viruses infect amoebal cells, more efficient cell-tracking techniques are needed. Just earlier this month, scientists from the Tokyo University of Science, led by Professor Masaharu Takemura, had reported the discovery of two new species of pandoravirus and mimivirus--both families of giant viruses infecting amoebae--from a riverbank in Japan. Prof Takemura says that continual discovery of viruses from soil is crucial from the standpoint of understanding the ecology of giant viruses.

More importantly, in a brand new study published in Frontiers in Microbiology, a team of scientists at Tokyo University of Science, once again led by Prof Takemura, tried to understand the behavior in which amoebal cells infected with different types of giant viruses. For this, they devised a new cell-tracking method that tackles the issues of conventional analysis methods. Prof Takemura elaborates on the motivation of the study, "Our aim was to understand how giant viruses infect amoebae in the natural environment and how this has affected to evolution of eukaryotes. For this, we wanted to develop a technique to quantitatively detect the time-dependent, sequential changes in cellular number, size, shape, and direction and distance of cell motility."

In their study, Prof Takemura and his team focused on amoebae that were infected by a family of giant virus called "marseillevirus". To understand the behavior of host cells infected with this particular type of virus, the scientists developed a new algorithm that can trace individual amoebal cells in a population of amoebae using time-lapse phase-contrast microscopic images. They named this algorithm as "Phase-contrast-based Kinetic Analysis Algorithm for Amoebae" or PKA3. Using PKA3, the scientists revealed new, interesting aspects of how amoebae react to a giant virus attack. For example, they quantitatively showed that giant virus-infected amoebal cells formed aggregates or "bunches." They inferred that this could be either an antiviral strategy of the host or how the virus spreads, shedding light on the manner in which the viral infection takes place. What's more, they managed to detect changes in the number of cells and the appearance of marseillevirus-infected amoebae much faster than by conventional methods. Interestingly, they could also analyze the time taken by amoebae to respond to a viral infection, providing useful information on the life cycle of amoebae and viruses and the relationship between them. Prof Takemura says, "Our algorithm was successful in visualizing the movement of cells in images produced by phase-contrast microscopy, a method widely used in cell biology. Also, it allowed quantification of various parameters. This research will greatly contribute to the demonstration of amoeba behavior infected with the giant virus."

Apart from studying giant viruses, this new algorithm could be used for various other applications, such as to study the dynamics of cancer cells, lymphocytes, macrophages, and neurons. In general, it could reveal new cellular phenomena by tracking exactly how these cells migrate. Prof Takemura concludes by saying, "Our new analytical method could be applied to all cells that can be observed with a phase-contrast microscope and can potentially be applied to various fields including cell biology, medicine, and biotechnology."

Indeed, a technique like this--which can potentially make cell biology research easier--was much needed!

Creating sustainable markets poses particular obstacles: a sustainable market must be continuously shaped and reshaped. This is the conclusion of three researchers in business administration and innovation at Linkoping University, who have used the Swedish biogas market as a case.

Supply and demand for biogas have increased considerably in Sweden during the past decades, but domestic production has ceased to grow in recent years. However, hopes are now high for a significant expansion, not least as several international companies have entered the market. These include Finnish Gasum, French AirLiquide (owner of Fordonsgas), and suppliers of biogas facilities such as Hitachi Zosen Inova. From its initial form as a local and regional phenomenon operated by municipalities and public transport companies, the market has now become both national and international, to a certain extent. Sweden now imports biogas, mainly from Denmark and other countries through the gas pipeline on the western coast of Sweden.

Only a few studies have examined how sustainable markets arise, are created and shaped. Three researchers at Linkoping University, who are also active in the national Biogas Research Center (BRC), have now published an article about this in the Elsevier journal Environmental Innovation and Societal Transitions. Based on previous research into sustainable transitions and the shaping of markets, they have developed a general framework that they use to analyse the development of the Swedish biogas market.

They draw three conclusions. The first is that exchange practices must be enabled for a market to arise, in which the actors also must agree on what kind of value the exchange involves. For a long period, the biogas market grew in local and regional contexts, and the actors were forced to frequently justify their choices. The use of biogas was questioned, and this led to intense debate in many municipalities, such as Helsingborg, Jönköping and Skövde. In the true meaning of the word, a "market" for biogas has only existed during the past 10-15 years.

"Initially, the market was solely within the public sector, while now large commercial companies have entered and brought with them more strict demands for profitability. You must be able to set a price and communicate all the benefits, such as the biofertiliser produced", says Mikael Ottosson, associate professor in marketing at the Division of Business Administration. He is one of three authors of the article, together with Hans Andersson, senior lecturer in business administration, and Professor Thomas Magnusson, who carries out research on innovation at the Division for Project, Innovations and Entrepreneurship.

The second requirement is to construct a narrative about the sustainable technology and product.

"Sustainability is directed towards the future and needs storytelling. You must make it credible that the solution offered can help to create a sustainable society. This is important not least to attract investors and to gain public investment support and subsidies", says Thomas Magnusson.

Finally, the third requirement is to prove the system, and provide reliable evidence that the technology works in practice. The requirements here are severe.

"The burden of proof lies with people who want to change things. In the case of wind power, the advocates have had to provide counter-arguments against many types of misgiving, such as that peaks in power generation will overload the network in stiff winds. Biogas has faced objections following problems with engines, empty filling stations and a bus that caught fire", Mikael Ottosson tells us.

"What is new is always seen as the poor relatives from the countryside who must prove themselves and deliver at least the same quality as what is already in place, independently of the sustainability aspect. This makes sustainability an additional component that must be considered, in addition to price and quality", he says.

The conclusions constitute three parts of a conceptual framework, each of which contributes to creating different types of value in a market.

The advantages and enablers of biogas are also its Achilles heel. Certain conditions must be fulfilled: not only must substrate be available, but there must be surrounding agricultural land where the biofertiliser can be used. But who should drive the large volume growth?

"The municipal level was optimal during the construction. Building a national or international market for biogas is more challenging than for other sustainable technologies. Solar panels and wind turbines are standard products today that can be pushed to the market and installed. Instead, biogas solutions are often based on local collaborations in networks with many different stakeholders", says Mikael Ottosson.

In the case of biogas, Sweden is unique in the degree to which the gas is used as vehicle fuel. Other countries mainly produce electricity and heat from biogas. The number of biogas-fuelled vehicles is now increasing again in Sweden, although not to the extent predicted by proponents. This may be due to a lack of models available. Even so, between January and November 2019, 5,000 new biogas cars were registered in Sweden. A major advance for biogas is, however, expected when both Volvo and Scania launch new engines for heavy trucks powered by liquid gas.

"Markets are created and recreated: the phenomenon is rather circular. But the main questions are, as always: Who will take the costs and make the investments required in the construction of a sustainable market? and: How much is to be financed by the public sector?", Hans Andersson states.

A novel composite film -- created by the bonding of an antimicrobial layer to conventional, clear polyethylene plastic typically used to vacuum-package foods such as meat and fish -- could help to decrease foodborne illness outbreaks, according to researchers in Penn State's College of Agricultural Sciences.

The antimicrobial lining of the film is comprised of a pullulan-based biopolymer produced from starch syrup during a fermentation process, which is already approved for use in foods. Pullulan, a water-soluble "polysaccharide," is essentially a chain of sugar, glycerin and cellulose molecules linked together. To kill pathogens such as Salmonella, Listeria and pathogenic E. coli, researchers infused the pullulan with Lauric arginate, made from naturally occurring substances and already approved for use in foods.

Development of the composite antimicrobial film is important because 76 million cases of foodborne illnesses occur each year in the U.S. alone, resulting in 300,000 hospitalizations and 5,000 deaths, according to the U.S. Centers for Disease Control and Prevention. In light of this problem and the commercial potential of this discovery, Penn State has applied for a provisional patent on the composite antimicrobial film.

The pullulan film slows the release of the antimicrobial, disbursing it at a predictable rate to provide continuous bacteria-killing activity, explained researcher Catherine Cutter, professor of food science. She added that without being impregnated into the film, the antimicrobial would run off the surface of a food product, such as meat; or evaporate.

Lauric arginate was chosen as the antimicrobial because it is a remarkable, broad-spectrum antimicrobial compound that proved highly effective in killing and limiting the growth of pathogens that cause foodborne illness, noted Cutter, assistant director of food safety and quality programs for Penn State Extension.

"Lauric arginate is a safe, completely nontoxic ingredient," she said. "It is hydrolyzed in the human body by chemical and metabolic pathways, which quickly break it into its naturally occurring components -- lauric acid and L-arginine."

Cutter's research group in the Department of Food Science has been experimenting with antimicrobial films made of pullulan for a decade. But she credits Abdelrahim Hassan, who spearheaded the latest study, for devising a procedure to fuse the pullulan-based antimicrobial layer to the polyethylene plastic -- allowing the novel composite to be born. Hassan, who was a visiting scholar in Cutter's lab when the research was conducted, is an associate professor of food safety and technology at Beni-Suef University in Egypt.

"Hassan figured out a way to get the pullulan to attach to polyethylene," Cutter said. "He modified the formulation of pullulan and changed the hydrophobicity of the plastic. These steps were important because polyethylene repels everything -- nothing sticks to it. So, the challenge was, how could we get pullulan to adhere to it."

Before settling on Lauric arginate, the researchers experimented with other food-grade antimicrobials incorporated into the antimicrobial layer such as thymol and nisin. The antimicrobial activity of the resulting composite films was evaluated against cocktails of Shiga toxin-producing E. coli, Salmonella spp., Listeria monocytogenes and Staphylococcus aureus.

"Films containing nisin were ineffective; thymol disrupted some pathogens but not others; and Lauric arginate inhibited the growth of the four types of bacteria," Hassan said.

Based on these preliminary results, Shiga toxin-producing E. coli, Salmonella spp., Listeria monocytogenes and Staphylococcus aureus were experimentally inoculated onto raw beef, raw chicken breast and ready-to-eat turkey breast, vacuum packaged with the composite antimicrobial film, sealed and placed into refrigerated storage for up to 28 days.

In findings published today (Jan. 20) in the International Journal of Food Microbiology, Hassan and Cutter reported that the composite antimicrobial film containing Lauric arginate significantly reduced foodborne pathogens on the experimentally inoculated surfaces of the raw and ready-to-eat muscle foods after refrigerated storage.

Cutter believes that the findings from this research will be of interest to the packaging and muscle food industries, as well as regulatory agencies that seek to reduce pathogens in the food supply. Although there was thought not long ago that biopolymers could entirely replace plastic in food packaging, Cutter believes that the composite nature of the antimicrobial film is still needed.

"Polyethylene exhibits many desirable properties, such as strength, transparency, gas permeability and water resistance," she said. "The novel composite film can give us antimicrobial properties and at the same time provide the strength and all the other desirable properties of polyethylene that the industry is still looking for."

Future research in Cutter's lab will evaluate how the composite antimicrobial film affects the shelf life of food products, and investigate consumer perceptions and acceptability of the novel film.

Opposing desires to congregate and maintain some personal space drive fruit flies to form orderly clusters, according to a study published today in eLife.

Many animals ranging from swarming insects to wildebeests form large, orderly groups. This collective behaviour is often crucial to survival. It may help animals find food, escape predators, enhance the way they sense their surroundings and augment their decision making. But the processes that enable these group gatherings are not well understood.

It can be difficult to study large animal groups in the wild, but studying smaller animals in the laboratory can help scientists tease apart the processes that drive animal clustering step by step. For this work, researchers in China looked at what drives clustering in the sociable fruit fly Drosophila melanogaster.

"Analysing the aggregation process in fruit flies would help us understand how individuals interact to form a social group and what senses are used during this process," says lead author Lifen Jiang, a PhD student at the School of Life Sciences, University of Science and Technology of China, Hefei. "Looking at this process in fruit flies may give us some insight into more complex collective behaviours in other animals."

In their experiments, Jiang and the team discovered that fruit flies placed in shallow, covered dishes spontaneously form clusters with regular spacing between flies. By observing the flies, the scientists learned that these formations are driven by fly-fly interactions in which the flies use their legs and wings to touch each other and then establish some personal space. But when the team systematically interfered with their senses, including sight, odour and touch, this stopped the flies from forming these neat clusters. "Depriving fruit flies of their senses resulted in abnormal responses to encountering another fly and a high failure rate of cluster formation," Jiang explains.

The researchers then showed that the flies' physical interactions with each other switch on their sensory nerve cells. Without these cells, they are unable to establish the usual socially acceptable distances between themselves and other flies that are necessary to form organised clusters.

"Our findings suggest that self-organisation in flies might rely on just a few simple rules," says senior author Yan Zhu, PhD, Professor at the Institute of Biophysics, Chinese Academy of Sciences, Beijing. "More studies are now needed to determine whether similar rules govern gatherings in larger animals."

(Boston)--Virginity testing is a complex, culturally mediated practice that is poorly understood by Western clinicians. Although there is published literature on the ethics of 'virginity' testing and on the lack of reliability of a hymen examination to determine 'virginity', little practical guidance has been published for clinicians who may encounter requests for virginity testing in the clinical setting.

Now, a researcher from Boston University School of Medicine (BUSM) is providing recommendations for primary care physicians who are asked to perform this procedure.

"While advocating for global elimination of the practice of virginity testing as a human rights violation, clinical practice is often more complicated and ethically nuanced, the clinician must act in the best interest of the patient which might include performing an evaluation. Upholding human rights does not have to be incompatible with providing a needed service to a patient, even if the practice does not fit into our social norm," explains the author of the article Sondra Crosby, MD, associate professor of medicine at BUSM.

According to Crosby changing social norms, attitudes and practices about 'virginity' testing will not occur easily and change must come from within the culture and be spearheaded by members of the community. "Engagement with religious and community leaders is crucial for enacting change," adds Crosby, who also is an associate professor of Health Law, Ethics & Human Rights at Boston University School of Public Health and a physician at Boston Medical Center.

She believes education about the lack of reliability and the possible harms of virginity testing should be provided in communities who follow this practice, through training community members, reading materials and inclusion in other reproductive health discussions. "Simply condemning the practice is not sufficient to successfully promote change, nor does it help the women we are obligated to protect."

Crosby recommends if a physician has a large population of patients from countries or communities where 'virginity' testing is practiced, they should use routine or other visits to discuss this issue and provide education on the matter. "While it is not possible to determine if someone is a "virgin" based on examination of the hymen, 'virginity' testing can be discussed as part of comprehensive sexual education and counselling during well-visits for all genders, adults and adolescents, as well as during pediatric and teenage preventive exams. Such conversations can help build trust; assess knowledge, attitudes and practice of at-risk patients; and allow the physician to anticipate future requests."

This article appears online in the journal BMJ Global Health.

New research by Dorothy P. Schafer, PhD, at the University of Massachusetts Medical School, reveals the molecular process in which synaptic connections in the brain are damaged in multiple sclerosis and how this contributes to neurodegenerative symptoms. The paper, published in Immunity, also shows how gene therapy may be used to preserve neural circuits and protect against vision loss in the disease.

These findings suggest a path for developing therapies that may protect synapses from the damaging effects of MS and could be broadly applicable to other neurodegenerative disorders, according to Dr. Schafer, assistant professor of neurobiology, and Sebastian Werneburg, PhD, a postdoctoral fellow in the Schafer lab.

"Most MS research and FDA-approved treatments focus on demyelination and axon death," said Schafer. "Far less is known about what happens to the synaptic connections between neurons, which has proven to be a key aspect of neurodegeneration likely leading to cognitive decline in other diseases such as Alzheimer's disease."

Multiple sclerosis is a neurological disease of the central nervous system affecting more than 2 million people worldwide. The disease involves an abnormal response of the body's peripheral immune system against the brain, spinal cord and optic nerves, which damages the fatty substance surrounding nerve fibers called myelin. Recurrent episodes of inflammation result in demyelination. As the myelin is stripped away, the nerve fibers are exposed to inflammatory attacks from the immune system and the transmission of nerve signals within the central nervous system are altered or stopped completely. A small subset of MS patients experience chronic progressive neurodegenerative symptoms accompanied by significant synaptic loss and central nervous system atrophy. This version of the disease is called progressive MS.

FDA-approved medications for treating MS have been developed to limit and reduce the number of relapses, which delay progression of the disease and minimize demyelination, but there is no cure for the disease and patients are still left with disability. Current therapies work to inhibit peripheral immune attack of the central nervous system and inflammatory demyelination, but the neurodegenerative aspects of the disease have proven harder to decelerate, particularly for patients with progressive MS.

Vison loss is one of the most common symptoms of MS and is often one of the first that patients notice. Problems with vision result from damage to the optic nerve that connects the eye to the brain or from lack of coordination in the eye muscle.

"The retinogeniculate system, which comprises neurons that extend their axons via the optic nerve to the thalamus in the brain, is an ideal model for investigating MS because it's easy to access for therapeutic intervention, subtle changes can be readily detected and the visional pathway is affected in almost half of all patients with the disease," said Dr. Werneburg.

Profound synaptic loss was observed in animal models as microglia engulfed and eliminated presynaptic connections. Microglia are the immune cells of the central nervous system and are emerging as key players in regulating neural circuit structure in health and disease. One of the vast number of functions microglia perform in the brain is similar to the role macrophages perform in the immune system: clearing cellular decay and dead neurons from tissue.

"We found the protein C3 in abundance at synapses," said Werneburg.

C3 is not normally found in adult brain tissue. C3 protein usually only shows up in neural tissue during the developmental stages of the brain when synapses are being pruned. Synaptic pruning eliminates weak or unused synapsis as the brain matures to help efficiency and conserve energy.

In the case of demyelinating disease, it is not known why C3 is being produced and activated. This complement protein binds to synapses, sending the signal to microglia that the otherwise healthy-seeming synapse should be eliminated. This leads microglia to attack synapses.

Schafer, in collaboration with Guangping Gao, PhD, the Penelope Booth Rockwell Professor in Biomedical Research, professor of microbiology & physiological systems, director of the UMMS Horae Gene Therapy Center and Viral Vector Core, and co-director of the Li Weibo Institute of Rare Disease, used a gene therapy approach and adeno-associated virus to deliver Crry, an inhibitor of C3, specifically to synapses in the visual system while leaving the rest of the brain untouched, to see if synapses could be spared and vision preserved. Crry is a natural inhibitor of complement proteins such as C3. These regulators help protect cells or tissue from unwanted attack by the immune system.

After injection of the AAV into the circuit, Crry localized to synapses and successfully preserved them by binding to C3 so microglia couldn't damage them.

"As a result of this inhibition, we saw improved visional function in mice," said Werneburg.

Schafer said the protective effects of the AAV-delivered inhibitor were specific to the visual circuit. "It's possible that therapies targeting different circuits of the brain can be used to protect against synaptic damage in other neurodegenerative diseases such as Alzheimer's."

The next step for Schafer and colleagues will be to determine how the C3 protein is being activated and produced during MS and other neurodegenerative diseases.

CHAMPAIGN, Ill. -- A team of University of Illinois researchers estimated the mortality costs associated with air pollution in the U.S. by developing and applying a novel machine learning-based method to estimate the life-years lost and cost associated with air pollution exposure.

Scholars from the Gies College of Business at Illinois studied the causal effects of acute fine particulate matter exposure on mortality, health care use and medical costs among older Americans through Medicare data and a unique way of measuring air pollution via changes in local wind direction.

The researchers - Tatyana Deryugina, Nolan Miller, David Molitor and Julian Reif - calculated that the reduction in particulate matter experienced between 1999-2013 resulted in elderly mortality reductions worth $24 billion annually by the end of that period. Garth Heutel of Georgia State University and the National Bureau of Economic Research was a co-author of the paper.

"Our goal with this paper was to quantify the costs of air pollution on mortality in a particularly vulnerable population: the elderly," said Deryugina, a professor of finance who studies the health effects and distributional impact of air pollution. "Understanding how air pollution affects mortality, health care use and medical costs is essential for crafting efficient environment policies because outside factors such as a person's preexisting health conditions can make it challenging to accurately estimate the causal effects of pollution on health."

About 25% of the elderly Medicare population was vulnerable to acute pollution shocks, according to the researchers.

"Our analysis shows that the most vulnerable Medicare beneficiaries are those who suffer from chronic conditions and have high health care spending," said Reif, a professor of finance and a faculty member of the Institute of Government and Public Affairs. "We estimate that members of the most vulnerable group - those with a life expectancy of less than one year - are over 30 times more likely to die from pollution than the typical Medicare beneficiary."

"Because we take a big data approach, we're able to see how air pollution affects the entire elderly population of the U.S. over those 14 years," said Miller, the Daniel and Cynthia Mah Helle Professor of Finance. "Medicare data is great because it has every interaction with the health care system in our sample for virtually every elderly person."

The typical air pollution research is more of a case study, Miller said.

"There's a pollution event in a certain city, and there's a mortality count around this event, but it's hard to get an accurate general estimate of the overall impact," he said. "Pollution is produced as a package: You burn stuff and it produces particulate matter, but it also produces other pollutants. Our methodology is able to take a lot of data, people and pollution events into account. And that allows us to more accurately identify the overall impact of pollution, because wind patterns affect these different pollutants in different ways. So we can tease apart which of these pollutants we think is most important and driving these mortality effects."

By exploiting the daily variation in acute fine particulate pollution exposure driven by changes in wind direction, the researchers found significant effects of exposure on mortality, hospitalizations and medical spending.

"A key part of the study was harnessing 40 billion observations with machine learning techniques," said Molitor, a professor of finance. "We used machine learning to predict how long people would have lived in the absence of the pollution event and to illuminate who is most vulnerable to pollution. One takeaway is that an individual's life expectancy - how much longer they can expect to live - is a much better measure of vulnerability to pollution than their age."

The scholars also found that increases in particulate matter lead to more emergency room visits, hospitalizations and higher patient spending.

"Mortality is only one of many potential costs of air pollution," Molitor said. "The elderly who aren't dying may engage in other costly activities such as going to the hospital for preventive or emergency care. Those steps may help them avoid death, but it doesn't mean that pollution has no cost to their health or finances."

Notably, the researchers also found that the failure to adjust for the preexisting health of those who die from an acute pollution event tends to overstate the mortality-reduction benefits of decreasing air pollution.

"An issue that arises when estimating mortality effects is whether those who die from pollution exposure would have passed away soon anyway without that external pollution shock," Molitor said. "If deaths caused by pollution occur disproportionately among the least healthy, then ignoring this factor could lead to an overstatement of the life years lost due to pollution."

"But we found that the typical person who dies as a result of pollution exposure isn't someone you would expect to die in a week or a month," Miller said. "It's people who have 3.6 years on average to live, compared with about 11 years for the typical elderly Medicare enrollee. So, although they are less healthy than the average Medicare recipient, these are people who we expect to have three and a half reasonably healthy years of life, and this should definitely not be ignored."

"Another way of thinking about our characterization of who dies from pollution is as an index of vulnerability," Molitor said. "We want to protect people from pollution, and we could do that by reducing pollution levels. But that can be costly and difficult for local governments to implement, especially if pollution is caused by something far away. By understanding who is most vulnerable to pollution, local policies and actions can be designed to better protect lives and to improve population resilience to pollution events."

For decades, there's been a widespread assumption among people with an interest in sports-related injury that youth football players are more vulnerable to concussion and other head injuries than their older, bigger counterparts.

The Virginia Tech Helmet Lab has published the first data validating that conventional wisdom, in a study released in the January issue of the Annals of Biomedical Engineering.

The research, funded by a five-year grant from the National Institute of Neurological Disorders and Stroke of the National Institutes of Health, demonstrated that the head accelerations leading to concussion in youth football players are lower than those that typically cause injury in high school, collegiate, and professional athletes -- data that will be critical for designing and testing protective equipment.

"These are the first biomechanical data characterizing concussion risk in kids," said Steve Rowson, an associate professor of biomedical engineering and mechanics and the director of the Virginia Tech Helmet Lab. "Children aren't just scaled-down adults: Differences in anatomy and physiology, like head-neck proportions and brain development, contribute to differences in tolerance to head impact. These results can lead to data-driven interventions to reduce risk in youth sports."

Kids between the ages of 9 and 14 make up the largest group of football players in the country. But the research cataloging head impacts on U.S. football fields, and determining which ones are most likely to cause injury, has focused on high school, collegiate, and pro players, limiting the understanding of what conditions lead to concussion in youth football.

In younger players, the fatty myelin sheaths that help protect brain cells haven't fully developed. They also tend to have larger heads relative to their bodies than adult players do, with less neck musculature to help absorb the force of an impact. For all these reasons, researchers had presumed that youth players were more susceptible to concussion. But they needed data to prove it.

Virginia Tech has been studying head impacts in football since 2003, when Stefan Duma, the Harry Wyatt Professor of Engineering and founder of the Helmet Lab, instrumented the helmets worn by the university's varsity football team with sensors to measure head impacts.

Since then, Duma, Rowson, and their research team have expanded their studies to more sports and a broader range of demographic groups. They've been studying youth players since they won this critical grant from the NIH in 2015.

For the study, they partnered with researchers at Brown University and Wake Forest University to track six different youth football teams in Virginia, North Carolina, and Rhode Island. More than 100 players wore helmets lined with sensors that measured the linear and rotational acceleration of their heads during four seasons' worth of practices and games, recording thousands of impacts. All concussions were diagnosed by clinicians at each site; neuropsychological testing before and after each season measured the players' cognitive function.

The National Operating Committee on Standards for Athletic Equipment, an independent standards body that certifies equipment including football helmets, provided additional funding that helped accelerate the data collection.

That data allowed the researchers to develop a mathematical relationship between the magnitude of a head impact and the risk of concussion. What they found was that youth players are on average more susceptible to concussion at lower levels of acceleration than high school and collegiate players are.

In high school and college players, the average concussive impact is associated with a head acceleration around 102 g, with similar values for pro athletes. In youth players, the new study found, the average concussive impact was associated with a head acceleration of only 62 g. The rotational acceleration values associated with concussion were similarly reduced, from 4,412 rad/s2 in adults to 2,609 rad/s2 in youth players.

"These numbers prove for the first time that youth players are at a higher risk of injury at lower head accelerations," Duma said, "but it is important to note that the overall head acceleration exposure in youth football is much lower than in adult football."

Despite that heightened susceptibility, concussions in youth football are relatively rare: Younger, lighter players collide with less force than adult athletes, so they're less likely to jostle their brains enough to cause serious injury.

But as with any sport, there's still a risk of injury. So effective protective equipment is critical -- and that's the practical value of this study, Duma explained. Knowing the levels of acceleration that put youth players at risk for concussion provides a benchmark to use for helmet testing.

Earlier this year, the Helmet Lab released the industry's first youth-specific football helmet ratings, evaluating the helmets with laboratory tests based on their on-field data.

"No one had ever come up with a rating system tailored to youth helmets, partly because the data didn't exist," said Duma, who also directs the university's Institute for Critical Technology and Applied Science. "Now we can evaluate helmets based on the actual risks youth players experience, and companies can use that information to design models specifically for this large group of players."