943 research outputs found
Francis Hollis Fay (1927-1994)
This obituary honours the achievements of Francis H. Fay (Bud) who was a distinguished marine mammalogist, a dedicated scholar, and a man of unwavering integrity who inspired colleagues, students, and friends. Bud's life was dedicated to the study of the life history of the Pacific walrus. This study commenced on St. Lawrence Island, Alaska, where his teachers, especially Charles and Vernon Slwooko, taught him a great deal about walrus ecology, while providing him with specimens he used to describe the reproduction, growth, and anatomy of Pacific Walruses, thus relying on, and recognizing the importance of, indigenous knowledge. In 1982 Bud published his monograph on walruses, Ecology and Biology of the Pacific Walrus, Odobenus rosmarus". The book was a masterful piece of scholarship and reflected not only years of hard work but also Bud's painstaking attention to detail. He did not stop there, however, and he continued to investigate walrus taxonomy, population biology, and ecology right up until the time of his death. His relentless search for knowledge of walruses led him to the Russian literature, and over the years he and Barbara carefully over 120 scientific articles from Russian into English. ... Bud was dedicated to international cooperation in research and management, as demonstrated by the enthusiasm with which he shared his translations of Russian literature and by his early and continuous activity as a member of the Steering-Planning Committee of the Marine Mammal Project under the U.S.-U.S.S.R. Agreement on Environmental Protection." ... [His passion for research, his editing, and his humor are greatly missed.
Mass Natural Mortality of Walruses (Odobenus rosmarus) at St. Lawrence Island, Bering Sea, Autumn 1978
In October-November 1978, several thousand living walruses came ashore in at least four localities on St. Lawrence Island where they had not been present before in this century. They hauled out also at two other sites which they have occupied annually but in much smaller numbers. At least 537 animals died on the haulout areas at that time, and approximately 400 other carcasses washed ashore from various sources. This was by far the greatest mortality of walruses ever recorded in an event of this kind. At least 15% of the carcasses on the haulouts were aborted fetuses, 24% were 5-6-month-old calves; the others were older animals ranging in age from 1 to 37 years old. About three-fourths of the latter on the haulouts were females; in the non-haulouts areas the sex ratio was about 1:1. Forty of the best preserved carcasses were examined by necropsy. The principal cause of death was identified as extreme torsion of the cervical spine, with resultant cerebrospinal hemorrhage, apparently due to traumatization by other walruses. Nearly all of the dead were extremely lean, having less than half as much subcutaneous fat as healthy animals examined in previous years
Optimisation of Ingredient Formulation in Processed Meat Products.
End of Project ReportReformed and restructured meat are two major categories of processed meat products.
Reformed meat products require intact meat pieces to bind together while restructured meat
products are extensively minced prior to restructuring. Salts such as sodium chloride and
phosphates together with mechanical treatment and heat, have been used to bind meat
pieces together. In the process the proteins in muscle become soluble, bind large amounts
of water and gel on heating.
While heat-induced gelation of soluble meat protein provides binding in reformed meat
products and reduces cook losses in restructured meat products, no binding occurs in raw
meat systems. Non-meat proteins, especially soya protein, are routinely used in processed
meat products, often in conjunction with salts, to increase water and fat binding during the
cooking process. However, such proteins do not bind intact meat pieces in either the raw
or cooked state.
Transglutaminase (TGase) is a food-grade commercially available enzyme which can
crosslink suitable proteins leading to the formation of a protein matrix (gel) and
immobilisation of large quantities of water. This property could improve the water-binding
properties of non-meat proteins in restructured meat products. The prospect of crosslinking
native meat proteins and non-meat proteins or native meat proteins on adjacent meat
pieces would make salt-free reformed meat products a realistic objective.
Hence, the main objective of this project was to study protein-protein interactions in
reformed and restructured meats, especially between meat proteins and added non-meat
proteins in the absence of salts but in the presence of a protein crosslinking enzyme.Department of Agriculture, Food and the Marin
Damage Identification for Prestressed Adjacent Box-Beam Bridges
Structural health monitoring (SHM) has gained considerable attention as a tool for monitoring the health of civil infrastructure. For bridge infrastructure, previous methods have focused on the detection of localized damage through modal parameters extracted from the longitudinal direction of the structure. This paper investigates a new damage detection method based on the change in the first vertical mode extracted from the transverse direction of the bridge. The mode is determined through application of modal curve fitting to frequency response functions (FRFs) that are formed using vertical response data obtained in the direction perpendicular to the bridge’s longitudinal axis. Using this method, both local damage and global damage in the bridge reveal themselves as having a localized effect on the bridge response. Furthermore, damage is revealed in such a way that it enables differentiation of the damage types. To demonstrate the effectiveness of the method, modal parameters were extracted from acceleration data obtained from a finite element model of a full bridge. Analysis of the modal parameters showed that the proposed approach could not only detect both local and global bridge damage, but could also differentiate between damage types using only one mode shape. The proposed method was compared to a previously developed SHM method
Modelling the Risks Remotely Piloted Aircraft Pose to People on the Ground
Worldwide there is much e ort being directed towards the development of a framework of air- worthiness regulations for remotely piloted aircraft systems (RPAS). It is now broadly accepted that regulations should have a strong foundation in, and traceability to, the management of the safety risks. Existing risk models for RPAS operations do not provide a simple means for incorporating the wide range of technical and operational controls into the risk analysis and evaluation processes. This paper describes a new approach for modelling and evaluating the risks associated with RPAS operations near populous areas based on the barrier bow tie (BBT) model. A BBT model is used to structure the underlying risk management problem. The model focuses risk analysis, evaluation, and decision making activities on the devices, people, and processes that can be employed to reduce risk. The BBT model and a comprehensive set of example risk controls are presented. The general model can be applied to any RPAS operation. The foundations for quantitative and qualitative assessments using a BBT model are also presented. The modelling and evaluation framework is illustrated through its application to a case-study rotary wing RPAS for two operational scenarios. The model can be used as a basis for determining airworthiness certification requirements for RPAS
A novel two-section tunable discrete mode Fabry-PÉrot laser exhibiting nanosecond wavelength switching
A novel widely tunable laser diode is proposed and demonstrated. Mode selection occurs by etching perturbing slots into the laser ridge. A two-section device is realized with different slot patterns in each section allowing Vernier tuning. The laser operates at 1.3 mum and achieves a maximum output power of 10 mW. A discontinuous tuning range of 30 nm was achieved with a side mode suppression greater than 30 dB. Wavelength switching times of approximately 1.5 ns between a number of wavelength channels separated by 7 nm have been demonstrated
Investigating the prevalence of reactive online searching in the COVID-19 pandemic
Background:
The ongoing coronavirus disease (COVID-19) pandemic has placed an unprecedented strain on global society, healthcare, governments and mass media. Public dissemination of government policies, medical interventions and misinformation has been remarkably rapid and largely unregulated during the COVID-19 pandemic, resulting in increased misinterpretations, miscommunication, and public panic. Being the first full-scale global pandemic of the digital age, COVID-19 has presented novel challenges pertinent to government advice, the spread of news and misinformation, and the trade-off between the accessibility of science and the premature public use of unproven medical interventions.
Objective:
This study aims to assess the use of internet search terms relating to COVID-19 information and misinformation during the global pandemic, identify which were most used in six affected countries, investigate any temporal trends and the likely propagators of key search terms, and determine any correlation between the per capita cases and deaths with the adoption of these search terms in each of the six countries.
Methods:
This study uses relative search volume data extracted from Google Trends for search terms linked to the COVID-19 pandemic alongside per capita case and mortality data extracted from the European Open Data Portal, to identify the temporal dynamics of the spread of news and misinformation during the global pandemic in six affected countries (Australia, Germany, Italy, Spain, United Kingdom, United States of America). A correlation analysis was carried out to ascertain any correlation between the temporal trends of search term use and the rise of per capita mortality and disease cases.
Results:
Of the selected search terms, most were searched immediately following promotion by governments, public figures or viral circulation of unfounded claims, but also relating to the publication of scientific resources, which were sometimes misinterpreted before further dissemination. Strong correlations were identified between the volume of these COVID-19-related search terms, and per capita mortality and cases.
Conclusions:
These findings illustrate the increased rate and volume of public consumption of novel information during a global healthcare crisis. The strong positive correlation between mortality and online searching, particularly in countries with lower COVID-19 testing rates, may demonstrate the imperative to safeguard official communications and dispel misinformation in these countries. Online news, government briefings and social media provide a powerful tool for the dissemination of important information to the public during pandemics, but their misuse, and the presentation of misrepresented medical information, should be monitored, minimised and addressed to safeguard public safety. Ultimately, governments, public health authorities and scientists have a moral imperative to safeguard the truth and maintain an accessible discourse with the public to inhibit fear
Final Report: International Workshop to Reconcile Methane Budgets in the Northern Permafrost Region
Keywords: methane, Arctic, permafrostAn International Workshop to Reconcile Methane Budgets in the Northern Permafrost Region, organized by the Study of Environmental Arctic Change (SEARCH), was held in Seattle on 7-9 March 2017. The workshop was funded by the National Science Foundation, the National Aeronautics and Space Administration, the U.S. Geological Survey, and the U.S. Arctic Research Commission. The primary goal was to produce a plan for reconciling methane budgets in the northern permafrost region. Forty-two scientists, including representatives of the atmospheric, inland (wetland and lakes), marine (coastal and oceanic), and remote sensing communities studying methane dynamics participated in developing the research plan. Eleven of the participants were early career scientists, and nine of the scientists were from institutions outside the United States. The first day of the workshop included keynote presentations that provided atmospheric, inland, and marine perspectives on developing a plan to reconcile methane budgets. There were also keynote presentations on the role of remote sensing in reconciling methane budgets. The second day of the workshop was devoted to breakout groups that developed plans from disciplinary perspectives, followed by breakouts of mixed disciplinary groups that discussed all three plans. The breakout groups identified key uncertainties and near-term and longer-term priorities for addressing questions about methane dynamics in the northern permafrost region. Participants committed to completing a paper describing a roadmap for the synthesis plan by the end of 2017, and each of the groups developed plans to address, by the end of 2018, near-term priorities to reduce uncertainties in methane budgets. The longer-term priorities include addressing possible sensitivities of methane emissions to climate variability and change in the region and evaluating the degree to which changes in methane dynamics are detectable. To address these longer-term priorities, there is a need to organize extant methane data for the northern permafrost region so that studies using these data can evaluate how enhancements to the methane observation network would improve estimates of methane emissions and the detection of trends. The Permafrost Action Team of SEARCH will develop research summaries and briefs based on the follow-on activities from the workshop.The National Science Foundation, the National Aeronautics and Space Administration, the U.S. Geological Survey, and the U.S. Arctic Research Commissio
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