29,605 research outputs found

    Pop III Stellar Masses and IMF

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    We provide a status report on our current understanding of the mass scales for Pop III.1 and Pop III.2 stars. Since the last review (Norman 2008), substantial progress has been made both numerically and analytically on the late stages of protostellar cloud core collapse, protostar formation and accretion, and stellar evolution taking into account cloud core properties and radiative feedback effects. Based on this, there are growing indications that primordial stars forming from purely cosmological initial conditions (Pop III.1) were substantially more massive than stars forming in preionized gas (Pop III.2) where HD cooling is important. Different stellar endpoints are predicted for these two types of Pop III stars with different chemical enrichment signatures: the former die as pair instability supernovae or intermediate mass black holes, whereas the latter die as iron core-collapse supernovae, leaving behind neutron star and stellar black hole remnants. We review recent simulations which show evidence for binary fragmentation at high densities, and comment on the significance of these results. We then summarize an attempt to directly calculate the Pop III.1 IMF taking into account the latest numerical and analytical models. We conclude with suggestions for the kind of simulations needed next to continue improving our understanding of Pop III star formation, which is a necessary input to understanding high redshift galaxy formation.Comment: 11 pages, 3 figures, Proceedings of "The First Stars and Galaxies: Challenges for the Next Decade", Austin, TX, March 8-11, 201

    The Law and Poor People’s Access to Health Care

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    Many companies today, in different fields of operations and sizes, have access to a vast amount of data which was not available only a couple of years ago. This situation gives rise to questions regarding how to organize and use the data in the best way possible. In this thesis a large database of pricing data for products within various market segments is analysed. The pricing data is from both external and internal sources and is therefore confidential. Because of the confidentiality, the labels from the database are in this thesis substituted with generic ones and the company is not referred to by name, but the analysis is carried out on the real data set. The data is from the beginning unstructured and difficult to overlook. Therefore, it is first classified. This is performed by feeding some manual training data into an algorithm which builds a decision tree. The decision tree is used to divide the rest of the products in the database into classes. Then, for each class, a multivariate time series model is built and each product’s future price within the class can be predicted. In order to interact with the classification and price prediction, a front end is also developed. The results show that the classification algorithm both is fast enough to operate in real time and performs well. The time series analysis shows that it is possible to use the information within each class to do predictions, and a simple vector autoregressive model used to perform it shows good predictive results

    THE JUDICIAL INDEPENDENCE THROUGH FAIR APPOINTMENTS ACT

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    The Judicial Independence Through Fair Appointments Act is a model act which provides a merit-based system for selecting a qualified, independent, accountable, and diverse judiciary based onclose study of existing systems. It provides the entire structure of a judicial selection by appointment system, building on concepts in established commission-based appointment plans and incorporating important refinements

    A Perspecive on Temper in the Court: A Forum on Judicial Civility

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    This Essay focuses on the issue of judicial civility, which is not about the merits of any particular decision or an improvement in decision-making, but an aim to improve the tone of justice in the courts. Despite the fact that the Code of Judicial Conduct mandates temperance as part of a judge\u27s job, abusive judge behavior has become too common

    Alternative Dispute Resolution in Patent Controversies

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    Mr. Balmer relates how ADR allows attorneys to tailor rules to resolve disputes in light of, e.g., party relationships and internal dynamics. He notes that, for life to go on, having resolution is itself an important goal

    a.k.a. Pablo: Mexican American Images for Television

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    The study of minority group images in mass media has been of considerable interest both to humanities and social science writers in the ethnic and media fields. Most investigations have focused upon the descriptive content of the minority portrayals, though a few have also dealt with related aspects of minority group reactions to images. Among the large volume of varied writings have been those which have considered minority group images in films, [1] images of Asian Americans in print and electronic media, [2] dissections of single television shows about minorities, [3] and responses of minority audiences and media critics to television portrayals of their group. [4] In general, studies have tended to find minority media images inaccurate, inadequate, and too infrequent. Explanations for these tendencies have usually emphasized how mass media reflect prejudices existing in the culture of the larger society, the faulty perceptions or decisions of the image·makers (writers, producers, directors, executive programmers), and the underrepresentation of minority persons in important and powerful image-shaping mass media positions

    The Law and Poor People’s Access to Health Care

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