552 research outputs found

    Insights into the Second Law of Thermodynamics from Anisotropic Gas-Surface Interactions

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    Thermodynamic implications of anisotropic gas-surface interactions in a closed molecular flow cavity are examined. Anisotropy at the microscopic scale, such as might be caused by reduced-dimensionality surfaces, is shown to lead to reversibility at the macroscopic scale. The possibility of a self-sustaining nonequilibrium stationary state induced by surface anisotropy is demonstrated that simultaneously satisfies flux balance, conservation of momentum, and conservation of energy. Conversely, it is also shown that the second law of thermodynamics prohibits anisotropic gas-surface interactions in "equilibrium", even for reduced dimensionality surfaces. This is particularly startling because reduced dimensionality surfaces are known to exhibit a plethora of anisotropic properties. That gas-surface interactions would be excluded from these anisotropic properties is completely counterintuitive from a causality perspective. These results provide intriguing insights into the second law of thermodynamics and its relation to gas-surface interaction physics.Comment: 28 pages, 11 figure

    Corporation tax as a problem of MNC organisational circuits: The case for unitary taxation

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    The tax practices of multinational corporations have become a matter of significant public and political concern. The underlying issues are rooted in the capacity of multinational corporations (MNCs) to construct organisational circuits that shift where sales, revenue and profit are reported. This capacity in turn becomes a focus because of the way MNCs are treated as a series of separate entities, subject to the arm’s length principle. This has become a classic example of a system whose current form and consequences were not foreseen when the original principles were set out. The continued existence of that system owes more to specific interests and inertia than it does to the absence of a viable alternative. Unitary taxation based on formula apportionment clearly resolves the underlying issues and unitary taxation may well ultimately emerge as a new generalised basis for corporate taxation. However, for it to do so, the problems of the current system and the advantages of the alternative need to be more clearly understood within academia, business and on a societal basis. This paper is a contribution to such an understanding

    Epigenetics and social inequalities in asthma and allergy

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    Respiratory illnesses, such as asthma and allergy disorders, are disproportionately more common among minority racial/ethnic groups and those of low socioeconomic status. In the United States, asthma prevalence and severity are highest among Puerto Ricans (19.2%), American Indians/Alaska Natives (13%), and Black Americans (12.7%) and higher in families living below the poverty threshold than among those living above it (11% vs 8%–9%).1 Many studies of asthma/allergy inequalities assume that genetic differences underlie racial/ethnic differences in these disorders, pointing to genetic ancestry differences between races, but most genetic variants fail to explain racial/ethnic differences and are usually studied only in White populations.2 In reality, racial and ethnic groups—terms that are often used interchangeably and in overlapping ways—can exhibit varying levels of genetic ancestry, cultural traits, and environmental exposures that all may be entangled together. Thus, any genetic finding differing by race/ethnicity can be confounded by social and environmental factors that also track with different ancestries. However, epigenetic mechanisms (i.e., heritable and stable changes in gene expression) may prove important in explaining these inequalities, as they are influenced by a combination of environmental, social, and genetic factors

    Innovation and HRM : absences and politics

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    This article analyses the role of HRM practices in the implementation of an innovative cross-functional approach to new product development (concurrent engineering, CE) in Eurotech Industries. Contrary to CE methodology stipulations, and despite supportive conditions, HRM received scant attention in the implementation process. Organizational power and politics were clearly involved in this situation, and this article explores how their play created such HRM &lsquo;absences&rsquo;. The article builds on a four-dimensional view of power in order to provide a deeper understanding of the embedded, interdependent and political nature of HRM practice and innovation.<br /

    Nanofluidic transport governed by the liquid/vapour interface

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    Liquid/vapour interfaces govern the behaviour of a wide range of systems but remain poorly understood, leaving ample margin for the exploitation of intriguing functionalities for applications. Here, we systematically investigate the role of liquid/vapour interfaces in the transport of water across apposing liquid menisci in osmosis membranes comprising short hydrophobic nanopores that separate two fluid reservoirs. We show experimentally that mass transport is limited by molecular reflection from the liquid/vapour interface below a certain length scale, which depends on the transmission probability of water molecules across the nanopores and on the condensation probability of a water molecule incident on the liquid surface. This fundamental yet elusive condensation property of water is measured under near-equilibrium conditions and found to decrease from 0.36 ± 0.21 at 30 °C to 0.18 ± 0.09 at 60 °C. These findings define the regime in which liquid/vapour interfaces govern nanofluidic transport and have implications for understanding mass transport in nanofluidic devices, droplets and bubbles, biological components and porous media involving liquid/vapour interfaces.Center for Clean Water and Clean Energy at MIT and KFUPM (Project R10-CW-09

    Achieving a high level of protection from pesticides in Europe:problems with the current risk assessment procedure and solutions

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    The regulation of pesticides in the European Union (EU) relies on a network of hard law (legislation and implementing acts) and soft law (non-legally binding guidance documents and administrative and scientific practices). Both hard and soft laws govern how risk assessments are conducted, but a significant role is left to the latter. Europe’s pesticide regulation is one of the most stringent in the world. Its stated objectives are to ensure an independent, objective and transparent assessment of pesticides and achieve a high level of protection for health and environment. However, a growing body of evidence shows that pesticides that have passed through this process and are authorised for use may harm humans, animals and the environment. The authors of the current paper – experts in toxicology, law and policy – identified shortcomings in the authorisation process, focusing on the EU assessment of the pesticide active substance glyphosate. The shortcomings mostly consist of failures to implement the hard or soft laws. But in some instances the law itself is responsible, as some provisions can only fail to achieve its objectives. Ways to improve the system are proposed, requiring changes in hard and soft laws as well as in administrative and scientific practices

    Diamond deposition on modified silicon substrates: Making diamond atomic force microscopy tips for nanofriction experiments

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    Fine-crystalline diamond particles are grown on standard Si atomic force microscopy tips, using hot filament-assisted chemical vapor deposition. To optimize the conditions for diamond deposition, first a series of experiments is carried out using silicon substrates covered by point-topped pyramids as obtained by wet chemical etching. The apexes and the edges of the silicon pyramids provide favorable sites for diamond nucleation and growth. The investigation of the deposited polycrystallites is done by means of optical microscopy, scanning electron microscopy and micro-Raman spectroscopy. The resulting diamond-terminated tips are tested in ultra high vacuum using contact-mode atomic force microscope on a stepped surface of sapphire showing high stability, sharpness, and hardnes

    The distortion of a cylinder with non-uniform axial heat conduction

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    Closed form expressions are developed for the thermoelastic curvature of the initially plane end faces of a traction free cylinder subjected to arbitrary axisymmetric heat flux, the curved surfaces being assumed insulated. The solution is developed from a potential function representation of displacement and temperature for an elastic layer. The reciprocal theorem is invoked to show that the tractions at the curved surface of the cylinder vary linearly along the axis and they are removed by superposition of biaxial bending. It is found that the curvature of the plane ends depends on the local heat flux and the mean heat flux, whilst the cylindrical face distorts into a cone.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/42669/1/10659_2004_Article_BF00042521.pd

    The Vehicle, Spring 1997

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    Vol. 38, No. 2 Table of Contents Poetry: Don QuixotePatrick Scanlanpage 1 Last SupperChristine Starrpage 1 Marriage VowsKristopher Clausingpage 2 The LibraryPatrick Lairpage 4 GuruJohn Dylan McNeilpage 5 Tripping in OzKim Evanspage 5 TranceStephanie Kavanaughpage 6 The CleftEmilie Roypage 7 FlannelAmanda Watsonpage 8 Strip PokerEbben Moorepage 8 IceJohn Dylan McNeilpage 9 ChloeMichael Kawapage 11 OrchardCarmella Cosenzapage 12 Jenn & Cookie MonsterJacob Tolbertpage 13 Barry ManilowKatie Wrightpage 14 GoodbyesShannon Goodallpage 15 Prose: Alice (A Short, Short Story)Carmella Cosenzapage 17 UntitledJoe Robesonpage 17 A New World AloneKendall W. Baumanpage 22 Biographiespage 35https://thekeep.eiu.edu/vehicle/1069/thumbnail.jp
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