120 research outputs found

    Teaching Research Data Management: An Undergraduate/Graduate Curriculum

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    With funding from the Institute of Museum and Library Services, the Libraries of the University of Massachusetts Medical School and Worcester Polytechnic Institute collaborated on a plan to expand the scope of science library practices and promote among medical, graduate, and undergraduate science students the preservation of scientific data in relevant repositories and archives. This paper outlines curriculum frameworks and learning needs for research data management instruction that can be delivered through a variety of methods. Individual modules are based on faculty and student interviews, as well as a comprehensive literature review

    Coherent master equation for laser modelocking

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    Modelocked lasers constitute the fundamental source of optically-coherent ultrashort-pulsed radiation, with huge impact in science and technology. Their modeling largely rests on the master equation (ME) approach introduced in 1975 by Hermann A. Haus. However, that description fails when the medium dynamics is fast and, ultimately, when light-matter quantum coherence is relevant. Here we set a rigorous and general ME framework, the coherent ME (CME), that overcomes both limitations. The CME predicts strong deviations from Haus ME, which we substantiate through an amplitude-modulated semiconductor laser experiment. Accounting for coherent effects, like the Risken-Nummedal-Graham-Haken multimode instability, we envisage the usefulness of the CME for describing self-modelocking and spontaneous frequency comb formation in quantum-cascade and quantum-dot lasers. Furthermore, the CME paves the way for exploiting the rich phenomenology of coherent effects in laser design, which has been hampered so far by the lack of a coherent ME formalism

    Phase-resolved terahertz self-detection near-field microscopy

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    At terahertz (THz) frequencies, scattering-type scanning near-field optical microscopy (s-SNOM) based on continuous wave sources mostly relies on cryogenic and bulky detectors, which represents a major constraint for its practical application. Here, we devise a THz s-SNOM system that provides both amplitude and phase contrast and achieves nanoscale (60-70nm) in-plane spatial resolution. It features a quantum cascade laser that simultaneously emits THz frequency light and senses the backscattered optical field through a voltage modulation induced inherently through the self-mixing technique. We demonstrate its performance by probing a phonon-polariton-resonant CsBr crystal and doped black phosphorus flakes

    Organic Geochemical Studies. I. Molecular Criteria for Hydrocarbon Genesis

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    In recent years the search for life-forms at the earliest periods of geological time has been continued not only at the morphological level but also at the molecular level. This has been possible as a result of the increase in the biochemical knowledge and with the advent of analytical techniques that are capable of describing the intimate molecular architecture of individual molecules in acute detail. The fundamental premises upon which this organic geochemical approach rest are the following: that certain molecules, possessing a characteristic structural skeleton, show a reasonable stability to degradation over long periods of geological time; that their structural specificity can be understood in terms of known biosynthetic sequences; and that their formation by any non-biological means is of negligible probability. In this manuscript it is proposed to critically re-examine these premises and to establish criteria whereby one can differentiate molecules derived from biological systems from those that have their origin in non-biological processes. The importance of establishing such criteria lies in the significance these criteria have in determining whether life exists, or has existed, on other planets. Within the very near future it may be possible to provide an initial answer to this question when the first lunar samples are returned to the earth for analysis

    Binge Eating and Weight-Related Quality of Life in Obese Adolescents

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    Limited data exist regarding the association between binge eating and quality of life (QOL) in obese adolescent girls and boys. We, therefore, studied binge eating and QOL in 158 obese (BMI ≥ 95th percentile) adolescents (14.5 ± 1.4 years, 68.0% female, 59% African-American) prior to weight-loss treatment. Youth completed an interview to assess binge eating and a questionnaire measure of QOL. Controlling for body composition, binge eating youth (n = 35), overall, reported poorer QOL in domains of health, mobility, and self-esteem compared to those without binge eating (ps < 0.05). Also, girls, overall, reported poorer QOL than boys in activities of daily-living, mobility, self-esteem, and social/interpersonal functioning (ps < 0.05). Girls with binge eating reported the greatest impairments in activities of daily living, mobility, self-esteem, social/interpersonal functioning, and work/school QOL (ps < 0.05). Among treatment-seeking obese adolescents, binge eating appears to be a marker of QOL impairment, especially among girls. Prospective and treatment designs are needed to explore the directional relationship between binge eating and QOL and their impact on weight outcomes

    Evaluation of the kinase domain of c-KIT in canine cutaneous mast cell tumors

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    BACKGROUND: Mutations in the c-KIT proto-oncogene have been implicated in the progression of several neoplastic diseases, including gastrointestinal stromal tumors and mastocytosis in humans, and cutaneous mast cell tumors (MCTs) in canines. Mutations in human mastocytosis patients primarily occur in c-KIT exon 17, which encodes a portion of its kinase domain. In contrast, deletions and internal tandem duplication (ITD) mutations are found in the juxtamembrane domain of c-KIT in approximately 15% of canine MCTs. In addition, ITD c-KIT mutations are significantly associated with aberrant KIT protein localization in canine MCTs. However, some canine MCTs have aberrant KIT localization but lack ITD c-KIT mutations, suggesting that other mutations or other factors may be responsible for aberrant KIT localization in these tumors. METHODS: In order to characterize the prevalence of mutations in the phospho-transferase portion of c-KIT's kinase domain in canine MCTs exons 16–20 of 33 canine MCTs from 33 dogs were amplified and sequenced. Additionally, in order to determine if mutations in c-KIT exon 17 are responsible for aberrant KIT localization in MCTs that lack juxtamembrane domain c-KIT mutations, c-KIT exon 17 was amplified and sequenced from 18 canine MCTs that showed an aberrant KIT localization pattern but did not have ITD c-KIT mutations. RESULTS: No mutations or polymorphisms were identified in exons 16–20 of any of the MCTs examined. CONCLUSION: In conclusion, mutations in the phospho-transferase portion of c-KIT's kinase domain do not play an important role in the progression of canine cutaneous MCTs, or in the aberrant localization of KIT in canine MCTs

    The Economic Gains to Colorado of Amendment 66

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