2,276 research outputs found

    Matrix isolation study of the photolysis of cyanogen azide. The infrared and ultraviolet spectra of the free radical NCN

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    Infrared and ultraviolet absorption spectra of free radical in photolysis of cyanogen azid

    Matrix isolation study of the reaction of f atoms with co infrared and ultraviolet spectrum of the free radical fco

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    Matrix isolation of reaction of fluorine atoms with carbon monoxide - infrared and ultraviolet spectrum of free radical fluorocarbon monoxid

    We Could, but Should We? Ethical Considerations for Providing Access to GeoCities and Other Historical Digital Collections

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    We live in an era in which the ways that we can make sense of our past are evolving as more artifacts from that past become digital. At the same time, the responsibilities of traditional gatekeepers who have negotiated the ethics of historical data collection and use, such as librarians and archivists, are increasingly being sidelined by the system builders who decide whether and how to provide access to historical digital collections, often without sufficient reflection on the ethical issues at hand. It is our aim to better prepare system builders to grapple with these issues. This paper focuses discussions around one such digital collection from the dawn of the web, asking what sorts of analyses can and should be conducted on archival copies of the GeoCities web hosting platform that dates to 1994.This research was supported by the Natural Sciences and Engineering Research Council of Canada, the Social Sciences and Humanities Research Council of Canada, the US National Science Foundation (grants 1618695 and 1704369), the Andrew W. Mellon Foundation, Start Smart Labs, and Compute Canada

    Techniques for improving reliability of computers

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    Modular design techniques improve methods of error detection, diagnosis, and recovery. Theoretical computer (MARCS (Modular Architecture for Reliable Computer Systems)) study deals with postulated and modeled technology indigenous to 1975-1980. Study developments are discussed

    Non-equivalence of key positively charged residues of the free fatty acid 2 receptor in the recognition and function of agonist versus antagonist ligands

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    Short chain fatty acids (SCFAs) are produced in the gut by bacterial fermentation of poorly digested carbohydrates. A key mediator of their actions is the G protein-coupled Free Fatty Acid 2 (FFA2) receptor and this has been suggested as a therapeutic target for the treatment of both metabolic and inflammatory diseases. However, a lack of understanding of the molecular determinants dictating how ligands bind to this receptor has hindered development. We have developed a novel radiolabelled FFA2 antagonist in order to probe ligand binding to FFA2 and in combination with mutagenesis and molecular modelling studies define how agonist and antagonist ligands interact with the receptor. Although both agonist and antagonist ligands contain negatively charged carboxylates that interact with two key positively charged arginine residues in transmembrane domains V and VII of FFA2, there are clear differences in how these interactions occur. Specifically, while agonists require interaction with both arginine residues to bind the receptor, antagonists require an interaction with only one of the two. Moreover, different chemical series of antagonist interact preferentially with different arginine residues. A homology model capable of rationalizing these observations was developed and provides a tool that will be invaluable for identifying improved FFA2 agonists and antagonists to further define function and therapeutic opportunities of this receptor

    Proceedings of a Summer Institute in Water Resources: Volume 1 - Philosophical, Institutional, and Legal Aspects of Water Resources

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    Foreward: Recognizing the need for training of individuals to meet the rapidly rising problems connected with water resources development, Utah State University, with National Science Foundation support, organized a Summer Institute in Water Resources for college teachers. it was hoped that participants carefully selected from all regions of the country would receive additional insight and stimulation to improve and enlarge water resources training programs at their own institutions. Thus, the accelerated dissemination of such knowledge on a national scale could be facilitated. Realizing further that the key to a successful institute of this nature lay in the excellence of its staff, efforts were made to obtain instructors with intimate knowledge and broad experience int he subject matter area they were asked to rpesent. In nearly every case those selected willingly accepted the invitation to participate, although this meant considerable monetary sacrifice and major adjustment of busy schedules. The subject matter treated paralleled regular offerings listed in the University catalog and is considered to be central or core to a water resources planning and management training program. one course treated the philosophical, historical, institutional, political, and legal aspects of water development. The responsibility for this course was shared jointly with Cleve H. Milligan, Charles E. Corker, and Wayne D. Criddle. The second course considered the principles of water resources economics and was presented by B. Delworth Gardner. The third course dealt with concepts of water quality management and was under the direction of P. H. McGauhey. The final course was on principles and procedures of regional resources planning and was presented jointly by Aaron Wiener, W. R. Derrick Sewell, and Harvey O. Banks. Having assembled a distinguished and diversified staff to present some of the best current professional thinking in the topics suggested in the preceding paragraph, it was felt most appropriate to attempt to put their lectures into writing. A proceedings of the Institute would have considerable utility beyong the Institute itself. Hence, the instructors were encouraged to prepare written material for the proceedings and were given secretarial and other assistance to aid them. This material has been organized according to the four major courses and is issued in four comanion volumes. Clearly, this has been a prodigious effort which required Institute staff and others to go the extra mile. Special thanks and recognition are due Mrs. Dorothy Riley who not only typed the entire proceedings but also attended to many details necessary for the successfult operations of the Institute. Jay M. Bagley served as director of the Institute and assumed a general coordinating and editing role in the development of these proceedings

    A Scientific Conception of Animal Welfare that Reflects Ethical Concerns

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    Scientific research on \u27animal welfare\u27 began because of ethical concerns over the quality of life of animals, and the public looks to animal welfare research for guidance regarding these concerns. The conception of animal welfare used by scientists must relate closely to these ethical concerns if the orientation of the research and the interpretation of the findings is to address them successfully. At least three overlapping ethical concerns are commonly expressed regarding the quality of life of animals: (1) that animals should lead natural lives through the development and use of their natural adaptations and capabilities, (2) that animals should feel well by being free from prolonged and intense fear, pain, and other negative states, and by experiencing normal pleasures, and (3) that animals should function well, in the sense of satisfactory health, growth and normal functioning of physiological and behavioural systems. Various scientists have proposed restricted conceptions of animal welfare that relate to only one or other of these three concerns. Some such conceptions are based on value positions about what is truly important for the quality of life of animals or about the nature of human responsibility for animals in their care. Others are operational claims: (1) that animal welfare research must focus on the functioning of animals because subjective experiences fall outside the realm of scientific enquiry, or (2) that studying the functioning of animals is sufficient because subjective experiences and functioning are closely correlated. We argue that none of these positions provides fully satisfactory guidance for animal welfare research. We suggest instead that ethical concerns about the quality of life of animals can be better captured by recognizing three classes of problems that may arise when the adaptations possessed by an animal do not fully correspond to the challenges posed by its current environment. (1) If animals possess adaptations that no longer serve a significant function in the new environment, then unpleasant subjective experiences may arise, yet these may not be accompanied by significant disruption to biological functioning. Thus, a bucket-fed calf may experience a strong, frustrated desire to suck, even though it obtains adequate milk. (2) If the environment poses challenges for which the animal has no corresponding adaptation, then functional problems may arise, yet these may not be accompanied by significant effects on subjective feelings. Thus, a pig breathing polluted air may develop lung damage without appearing to notice or mind the problem. (3) Where animals have adaptations corresponding to the kinds of environmental challenges they face, problems may still arise if the adaptations prove inadequate. For example, an animal\u27s thermoregulatory adaptations may be insufficient in a very cold environment such that the animal both feels poorly and functions poorly. We propose that all three types of problems are causes of ethical concern over the quality of life of animals and that they together define the subject matter of animal welfare science

    GPR35 as a Novel Therapeutic Target

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    G protein-coupled receptors (GPCRs) remain the best studied class of cell surface receptors and the most tractable family of proteins for novel small molecule drug discovery. Despite this, a considerable number of GPCRs remain poorly characterized and in a significant number of cases, endogenous ligand(s) that activate them remain undefined or are of questionable physiological relevance. GPR35 was initially discovered over a decade ago but has remained an “orphan” receptor. Recent publications have highlighted novel ligands, both endogenously produced and synthetic, which demonstrate significant potency at this receptor. Furthermore, evidence is accumulating which highlights potential roles for GPR35 in disease and therefore, efforts to characterize GPR35 more fully and develop it as a novel therapeutic target in conditions that range from diabetes and hypertension to asthma are increasing. Recently identified ligands have shown marked species selective properties, indicating major challenges for future drug development. As we begin to understand these issues, the continuing efforts to identify novel agonist and antagonist ligands for GPR35 will help to decipher its true physiological relevance; translating multiple assay systems in vitro, to animal disease systems in vivo and finally to man

    Multi-label classification using ensembles of pruned sets

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    This paper presents a Pruned Sets method (PS) for multi-label classification. It is centred on the concept of treating sets of labels as single labels. This allows the classification process to inherently take into account correlations between labels. By pruning these sets, PS focuses only on the most important correlations, which reduces complexity and improves accuracy. By combining pruned sets in an ensemble scheme (EPS), new label sets can be formed to adapt to irregular or complex data. The results from experimental evaluation on a variety of multi-label datasets show that [E]PS can achieve better performance and train much faster than other multi-label methods
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