3,604 research outputs found

    "Outside, it is snowing": Experience and finitude in the nonrepresentational landscapes of Alain Robbe-Grillet

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    Copyright © 2008 PionRomanillos J L, 2008. The definitive, peer-reviewed and edited version of this article is published in Environment and Planning D: Society and Space 26(5) 795 – 822 DOI: 10.1068/d6207This paper presents and explicates the anonymous and impersonal spatialities tentatively mapped in the novels of Alain Robbe-Grillet. Emerging from the kinds of landscapes and visualities articulated, these spatialities are at odds with the kind of anthropocentrism characteristic of phenomenological narratives of spatial experience that would start from an apparently stable human-subject position. It is argued that his body of literature dismantles the anthropocentric narratives and biographies that would produce in both the space of the world and the ‘phenomenological subject’ an unwarranted depth and naturalism. Importantly, and reflecting the theoretical turn towards the being of language, Robbe-Grillet questions the legitimacy of linguistic subjects to capture the spaces of the visible. As such, it is argued that his literature reflects an experience of the critiques of phenomenology. Importantly, this ‘critique’ goes hand in hand with the kinds of spatialities and landscapes that are rendered in the novels—the indefinite perspectives they open up, the paradoxical visualities they sustain or deny, and the disorientation they inject into the heart of spatial experience. These literary effects produce a nonanthropocentric and nonpersonal spatiality which, although contributing to an erasure of the ‘subject’, at the same time expose and open up a sociospatiality based on singularities, intensities, and finitude

    Characterizing receptive field selectivity in area V2

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    The computations performed by neurons in area V1 are reasonably well understood, but computation in subsequent areas such as V2 have been more difficult to characterize. When stimulated with visual stimuli traditionally used to investigate V1, such as sinusoidal gratings, V2 neurons exhibit similar selectivity (but with larger receptive fields, and weaker responses) relative to V1 neurons. However, we find that V2 responses to synthetic stimuli designed to produce naturalistic patterns of joint activity in a model V1 population are more vigorous than responses to control stimuli that lacked this naturalistic structure (Freeman, et. al. 2013). Armed with this signature of V2 computation, we have been investigating how it might arise from canonical computational elements commonly used to explain V1 responses. The invariance of V1 complex cell responses to spatial phase has been previously captured by summing over multiple “subunits” (rectified responses of simple cell-like filters with the same orientation and spatial frequency selectivity, but differing in their receptive field locations). We modeled V2 responses using a similar architecture: V2 subunits were formed from the rectified responses of filters computing the derivatives of the V1 response map over frequencies, orientations, and spatial positions. A V2 complex cell” sums the output of such subunits across frequency, orientation, and position. This model can qualitatively account for much of the behavior of our sample of recorded V2 neurons, including their V1-like spectral tuning in response to sinusoidal gratings as well as the pattern of increased sensitivity to naturalistic images

    Predissociation mechanism for the lowest ¹Πu states of N₂

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    Separate coupled-channel Schrödinger-equation (CSE) models of the interacting ¹Πu (b,c,o) and ³Πu (C,C′) states of N₂ are combined, through the inclusion of spin-orbit interactions, to produce a five-channel CSE model of the N₂predissociation. Comparison of the model calculations with an experimental database, consisting principally of detailed new measurements of the vibrational and isotopic dependence of the Πu1linewidths and lifetimes, provides convincing evidence that the predissociation of the lowest ¹Πu levels in N2 is primarily an indirect process, involving spin-orbit coupling between the b¹Πu- and C³Πu-state levels, the latter levels themselves heavily predissociated electrostatically by the C′³Πu continuum. The well-known large width of the b(v=3) level in ¹⁴N₂ is caused by an accidental degeneracy with C(v=9). This CSE model provides the first quantitative explanation of the predissociation mechanism for the dipole-accessible ¹Πu states of N₂, and is thus likely to prove useful in the construction of realistic radiative-transfer and photochemical models for nitrogen-rich planetary atmospheres.This work was partially supported by the Australian Research Council Discovery Program

    Healthy worker survivor analysis in an occupational cohort study of Dutch agricultural workers

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    OBJECTIVES: High microbial exposures in farmers and agricultural workers are associated with less atopy. Although it has been speculated that healthy worker survival could be an explanation, this has not been studied so far. Therefore, we investigated the presence of healthy worker survival in a five-year follow-up study of an occupational cohort of Dutch farmers and agricultural industry (company) workers. METHODS: We compared baseline demographic characteristics, respiratory health, atopy and endotoxin exposure of 259 workers followed up with 124 workers lost to follow-up. Additionally, baseline health status of 31 participants who had changed to lower exposure jobs at follow-up was compared to those with similar or higher exposure jobs at follow-up. RESULTS: In general, no major healthy worker survival effect was found. Nonetheless, small differences were observed between subjects included in follow-up and those lost to follow-up. Those lost to follow-up were older, had a lower peak expiratory flow, and were less often raised on a farm. Company workers lost to follow-up with a farm childhood had more often self-reported allergy, but this was not observed for subjects with atopic sensitization or other respiratory symptoms. No differences were found for any of the studied characteristics in participants with lower exposure at follow-up compared to participants with similar or higher exposure at follow-up. CONCLUSIONS: No major healthy worker survival is present in this organic dust exposed cohort. Differences between participants lost to follow-up and participants included in follow-up with regard to health characteristics are small and unlikely to explain the previously reported inverse associations between endotoxin exposure and atopy

    The Use of a Vaginal Conductivity Probe to Influence Calf Sex Ratio via Altered Insemination Time

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    One hundred eighty-nine mixed breed beef heifers from 13 consignors enrolled in the MACEP heifer development project were utilized in this study. Heifers were synchronized by feeding 0.5 mg melengestrol acetate (MGA) per head per day for 14 days followed by an injection of prostaglandin F2a (PGF2a; 25 mg Lutalyse®) 17 days after the last MGA feeding. Each heifer was fitted with a Heatwatch® transmitter on the morning of PGF2a administration to facilitate detection of estrus. Vaginal conductivity measurements were taken using an Ovatec® probe every 12 hours for 96 hours beginning at the time of PGF2a injection. Heifers randomly assigned to produce a female calf were inseminated near the onset of estrus (as indicated by probe values of £ 55 on the decline). Heifers randomly assigned to produce a male calf were inseminated approximately 24 hours after the onset of estrus (as indicated by probe values of ³ 60 on the incline). All heifers not inseminated by 96 hours after PGF2a were mass inseminated in an attempt to impregnate as many heifers as possible. Heifers that were diagnosed as pregnant as a result of the artificial insemination were subjected to ultrasonography for fetal sex determination. Only 70 of the 189 heifers (37.0%) exhibited estrus according to Heatwatch® and incidence of estrus was influenced by heifer average daily gain, reproductive tract score, and disposition score. Heifers receiving a disposition score of 3 (78.7) had a higher (P\u3c.05) probe reading at AI than those receiving a disposition score of 1 or 2 (70.8 and 72.5, respectively). Heifers with probe readings at insemination of 80 - 84 and \u3e 84 had lower (P\u3c.05) pregnancy rates to AI (13.6 and 0.0%, respectively) than heifers with probe readings in the ranges of \u3c 60, 60 - 64, 65 - 69, 70 - 74, and 75 - 79 (35.7, 40.9, 31.4, 35.3, and 26.9% respectively). Heifers that were bred when probe values were increasing had a lower (P\u3c.05) percentage of male fetuses (34.4%) than those bred during a period of decreasing probe values (69.2% male fetuses). These results demonstrate that a vaginal conductivity probe may be a useful tool to determine an insemination time that could potentially alter calf sex ratio

    Further Evidence for Chemical Fractionation from Ultraviolet Observations of Carbon Monoxide

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    Ultraviolet absorption from interstellar 12CO and 13CO was detected toward rho Oph A and chi Oph. The measurements were obtained at medium resolution with the Goddard High Resolution Spectrograph on the Hubble Space Telescope. Column density ratios, N(12CO)/N(13CO), of 125 \pm 23 and 117 \pm 35 were derived for the sight lines toward rho Oph A and chi Oph, respectively. A value of 1100 \pm 600 for the ratio N(12C16O)/N(12C18O) toward rho Oph A was also obtained. Absorption from vibrationally excited H_2 (v" = 3) was clearly seen toward this star as well. The ratios are larger than the isotopic ratios for carbon and oxygen appropriate for ambient interstellar material. Since for both carbon and oxygen the more abundant isotopomer is enhanced, selective isotopic photodissociation plays the key role in the fractionation process for these directions. The enhancement arises because the more abundant isotopomer has lines that are more optically thick, resulting in more self shielding from dissociating radiation. A simple argument involving the amount of self shielding [from N(12CO)] and the strength of the ultraviolet radiation field premeating the gas (from the amount of vibrationally excited H_2) shows that selective isotopic photodissociation controls the fractionation seen in these two sight lines, as well as the sight line to zeta Oph.Comment: 40 pages, 8 figures, to appear in 10 July 2003 issue of Ap

    Application of quasi-Monte Carlo methods to PDEs with random coefficients -- an overview and tutorial

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    This article provides a high-level overview of some recent works on the application of quasi-Monte Carlo (QMC) methods to PDEs with random coefficients. It is based on an in-depth survey of a similar title by the same authors, with an accompanying software package which is also briefly discussed here. Embedded in this article is a step-by-step tutorial of the required analysis for the setting known as the uniform case with first order QMC rules. The aim of this article is to provide an easy entry point for QMC experts wanting to start research in this direction and for PDE analysts and practitioners wanting to tap into contemporary QMC theory and methods.Comment: arXiv admin note: text overlap with arXiv:1606.0661

    Residual Stress Determination of Cast Aluminium Benchmark Components Using Strain Relief Techniques

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    Background: Residual stress development in precipitation strengthened aluminium foundry alloys has seen little attention, despite the prevalence of their use over a wide array of applications. Objective: This study aims at the evaluation of the residual stress in a cast aluminium benchmark that develops during precipitation heat treatment and determines the preferable stress relaxing techniques for such applications.Methods: The stress states in the as-cast, T4 and T6 tempers of the same AlSi7Cu0.5Mg (A356 with 0.5 wt% Cu) sample were determined through a novel application of the contour method, standard hole drilling, deep hole drilling and incremental deep hole drilling. Results: The results of all measurement techniques lie within approximately 40 MPa for all regions available for comparison, with the greatest differences occurring between the contour method and deep hole drilling for the T6 component. It is shown that the peak tensile residual stresses are almost identical between the heat-treated components (75 MPa), but the distribution and magnitude of compressive residual stress are found to be significantly different. Conclusions: Among the measurement techniques evaluated, the contour method and incremental hole drilling are found to be more suitable for T6 temper, while all techniques perform equally well for T4 temper due to its relatively low strength. It is hypothesised that the difference between the as-cast and heat-treated samples is due to solution heat treatment and quenching, while the difference in T4 and T6 tempers is attributed to the response to ageing

    A Dimension-Adaptive Multi-Index Monte Carlo Method Applied to a Model of a Heat Exchanger

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    We present an adaptive version of the Multi-Index Monte Carlo method, introduced by Haji-Ali, Nobile and Tempone (2016), for simulating PDEs with coefficients that are random fields. A classical technique for sampling from these random fields is the Karhunen-Lo\`eve expansion. Our adaptive algorithm is based on the adaptive algorithm used in sparse grid cubature as introduced by Gerstner and Griebel (2003), and automatically chooses the number of terms needed in this expansion, as well as the required spatial discretizations of the PDE model. We apply the method to a simplified model of a heat exchanger with random insulator material, where the stochastic characteristics are modeled as a lognormal random field, and we show consistent computational savings

    Про підготовку навчального посібника з краєзнавства для вищих навчальних закладів України

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    У статті обґрунтовується необхідність підготовки навчального посібника з національного краєзнавства для вищих навчальних закладів України, висвітлено стан його підготовки, концепція та окремі, найбільш важливі і дискусійні аспекти змісту майбутнього посібника.В статье обосновывается необходимость подготовки учебного пособия по национальному краеведению для высших учебных заведений Украины, показана степень его подготовки, концепция и отдельные, наиболее важные и дискуссионные аспекты будущего учебника.In the article the necessity of preparation of the tutorial of local history for higher educational establishments in Ukraine is settled down, the state of its preparation, conception and particular, most essential and debatable aspects of the content of the manual are covered
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