1,089 research outputs found

    A STATISTICAL EXAMINATION OF YIELD SWITCHING FRAUD IN THE FEDERAL CROP INSURANCE PROGRAM

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    An over-parameterized statistical yield-switching-fraud model is developed. Over-parameterized procedures are reviewed. Five percent of 206,952 producers (thirteen percent in one state) have suspicious yield patterns, elect higher coverage, and increase total multiple-unit indemnifications up to ten percent in some states and up to 30 percent at some coverage levels.Crop Production/Industries, Risk and Uncertainty,

    A flexible eye-safe lidar instrument for elastic-backscatter and DIAL

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    Developments in lidar have been driven largely by improvements in two key technologies: lasers and detectors. We describe here a lidar instrument for atmospheric remote sensing using the elastic-backscatter and differential-absorption lidar (DIAL) techniques. The instrument features an all-solid-state laser source combined with a flexible approach to detection providing portability, eye-safe operation and high sensitivity. The system is built around a custom-designed Newtonian telescope with a 0.38 m diameter primary mirror. Laser sources and detectors attach directly to the side of the telescope allowing for flexible customization with a range of equipment. The laser source is based on an optical parametric oscillator (OPO). The OPO is pumped by a neodymiumbased diode-laser pumped solid-state laser and angle-tuned by rotating the nonlinear conversion crystal. This provides a wide range of available wavelengths suitable for lidar within the 1.55 µm to 3.10 µm spectral region, where there exists a relatively high exposure limit for eye safety. The OPO delivers 1 mJ output pulse energy which is expanded and then transmitted coaxially from the telescope. Our goal is to make vertically-resolved measurements of greenhouse gas concentrations using DIAL. The source can rapidly be tuned between the on-line and off-line wavelengths to make a DIAL measurement. The use of the 1.6 µm wavelength region allows for several detection schemes. Whilst photodiode detectors are a very low-cost solution their limited sensitivity restricts the maximum range over which a signal can be detected. We therefore have designed the instrument to support alternative detection schemes including avalanche photodiodes (APDs)

    Nanothermal characterization of amorphous and crystalline phases in chalcogenide thin films with scanning thermal microscopy

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    The thermal properties of amorphous and crystalline phases in chalcogenide phase change materials (PCM) play a key role in device performance for non-volatile random-access memory. Here, we report the nanothermal morphology of amorphous and crystalline phases in laser pulsed GeTe and Ge2Sb2Te5 thin films by scanning thermal microscopy (SThM). By SThM measurements and quantitative finite element analysis simulations of two film thicknesses, the PCM thermal conductivities and thermal boundary conductances between the PCM and SThM probe are independently estimated for the amorphous and crystalline phase of each stoichiometry

    Desarrollo de la competencia de interpretaci?n a traves del genero narrativo ?cuentos fant?sticos? en los estudiantes del grado quinto del Colegio Mayor del Castillo de Melgar Tolima, tomando como referencia el contexto escolar

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    104 p. Recurso Electr?nicoLa presente investigaci?n busca que los estudiantes de grado quinto del Colegio Mayor del Castillo, fortalezcan la producci?n textual por medio del g?nero narrativo ?cuentos fant?sticos?, ya que en cuanto a comprensi?n y producci?n de textos se refiere, se da la convicci?n a trav?s del proceso de observaci?n con indiferencia y apat?a en el ?rea de lengua castellana, puesto que los estudiantes de este grado no sienten agrado al leer cualquier texto, y mucho menos tener que interpretarlo; se realiza una serie de talleres donde se vinculan grados de dificultad, a trav?s de los mismos se generan inc?gnitas de como contribuir a este grado una mayor comprensi?n e interpretaci?n. La propuesta se hinc? en la ejecuci?n de talleres pedag?gicos como estrategia did?ctica para fortalecer el proceso de producci?n textual y contribuir a la competencia interpretativa, donde se tuvo en cuenta la planificaci?n, contextualizaci?n y la revisi?n continua de dicho proceso. Observar el conjunto de evidencias en cuanto se inici? la investigaci?n muestra la deficiencia interpretativa, y desconocimiento a la producci?n textual de cuentos fant?sticos, a los resultados finales han sido realmente satisfactorios, es decir que de forma constante se manejaron distintas estrategias, permitiendo que los estudiantes desarrollaran una visi?n interpretativa para fortalecer el desarrollo de las capacidades comunicativas incorporando la l?dica, tomando como referencia, las experiencias vividas, reflejando el gran avance, fortaleciendo as? la competencia interpretativa a lo largo de la investigaci?n, en la orientaci?n y aplicaci?n de los talleres forjados en producci?n textual de calidad, con l?xico enriquecido la cual asemejan a las experiencias de su entorno inmediato.The present research seeks that the fifth grade students of the Castillo High School, strengthen the textual production through the narrative genre "fantastic stories", since in terms of understanding and production of texts is referred, conviction is given through Process of observation with indifference and apathy in the area of Castilian language, since students of this grade do not enjoy reading any text, let alone having to interpret it; There is a series of workshops where degrees of difficulty are linked, through which they generate unknowns of how to contribute to this degree a greater understanding and interpretation. The proposal focused on the execution of pedagogical workshops as a didactic strategy to strengthen the textual production process and contribute to the interpretative competence, which took into account the planning, contextualization and continuous revision of said process. Observing the set of evidences as soon as the research began showed the interpretative deficiency, and ignorance of the textual production of fantastic stories, the final results have been really satisfactory, that is to say that different strategies were constantly handled, allowing the students Develop an interpretive vision to strengthen the development of communicative capacities incorporating the playful, taking as a reference, the lived experiences, reflecting the great advance, thus strengthening the interpretative competence throughout the investigation, in the orientation and application of the forged workshops In quality textual production, with enriched lexicon which resemble the experiences of their immediate environment. Keyworks: Textual production, pedagogical workshops, textual production

    Dynamical Tides in Eccentric Binaries and Tidally-Excited Stellar Pulsations in KEPLER KOI-54

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    Recent observation of the tidally-excited stellar oscillations in the main-sequence binary KOI-54 by the KEPLER satellite provides a unique opportunity for studying dynamical tides in eccentric binary systems. We develop a general theory of tidal excitation of oscillation modes of rotating binary stars, and apply our theory to tidally excited gravity modes (g-modes) in KOI-54. The strongest observed oscillations, which occur at 90 and 91 times the orbital frequency, are likely due to prograde m=2 modes (relative to the stellar spin axis) locked in resonance with the orbit. The remaining flux oscillations with frequencies that are integer multiples of the orbital frequency are likely due to nearly resonant m=0 g-modes; such axisymmetric modes generate larger flux variations compared to the m=2 modes, assuming that the spin inclination angle of the star is comparable to the orbital inclination angle. We examine the process of resonance mode locking under the combined effects of dynamical tides on the stellar spin and orbit and the intrinsic stellar spindown. We show that KOI-54 can naturally evolve into a state in which at least one m=2 mode is locked in resonance with the orbital frequency. Our analysis provides an explanation for the fact that only oscillations with frequencies less than 90-100 times the orbital frequency are observed. We have also found evidence from the published KEPLER result that three-mode nonlinear coupling occurs in the KOI-54 system. We suggest that such nonlinear mode coupling may explain the observed oscillations that are not harmonics of the orbital frequency.Comment: 15 pages, 5 figures, accepted by MNRA

    Effects of study design and allocation on participant behaviour-ESDA: study protocol for a randomized controlled trial

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    Background: What study participants think about the nature of a study has been hypothesised to affect subsequent behaviour and to potentially bias study findings. In this trial we examine the impact of awareness of study design and allocation on participant drinking behaviour. Methods/Design: A three-arm parallel group randomised controlled trial design will be used. All recruitment, screening, randomisation, and follow-up will be conducted on-line among university students. Participants who indicate a hazardous level of alcohol consumption will be randomly assigned to one of three groups. Group A will be informed their drinking will be assessed at baseline and again in one month (as in a cohort study design). Group B will be told the study is an intervention trial and they are in the control group. Group C will be told the study is an intervention trial and they are in the intervention group. All will receive exactly the same brief educational material to read. After one month, alcohol intake for the past 4 weeks will be assessed. Discussion: The experimental manipulations address subtle and previously unexplored ways in which participant behaviour may be unwittingly influenced by standard practice in trials. Given the necessity of relying on self-reported outcome, it will not be possible to distinguish true behaviour change from reporting artefact. This does not matter in the present study, as any effects of awareness of study design or allocation involve bias that is not well understood. There has been little research on awareness effects, and our outcomes will provide an indication of the possible value of further studies of this type and inform hypothesis generation

    An evaluation of the effects of lowering blood alcohol concentration limits for drivers on the rates of road traffic accidents and alcohol consumption: a natural experiment

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    Background: Drink driving is an important risk factor for road traffic accidents (RTAs), which cause high levels of morbidity and mortality globally. Lowering the permitted blood alcohol concentration (BAC) for drivers is a common public health intervention that is enacted in countries and jurisdictions across the world. In Scotland, on Dec 5, 2014, the BAC limit for drivers was reduced from 0·08 g/dL to 0·05 g/dL. We therefore aimed to evaluate the effects of this change on RTAs and alcohol consumption. Methods: In this natural experiment, we used an observational, comparative interrupted time-series design by use of data on RTAs and alcohol consumption in Scotland (the interventional group) and England and Wales (the control group). We obtained weekly counts of RTAs from police accident records and we estimated weekly off-trade (eg, in supermarkets and convenience stores) and 4-weekly on-trade (eg, in bars and restaurants) alcohol consumption from market research data. We also used data from automated traffic counters as denominators to calculate RTA rates. We estimated the effect of the intervention on RTAs by use of negative binomial panel regression and on alcohol consumption outcomes by use of seasonal autoregressive integrated moving average models. Our primary outcome was weekly rates of RTAs in Scotland, England, and Wales. This study is registered with ISRCTN, number ISRCTN38602189. Findings: We assessed the weekly rate of RTAs and alcohol consumption between Jan 1, 2013, and Dec 31, 2016, before and after the BAC limit came into effect on Dec 5, 2014. After the reduction in BAC limits for drivers in Scotland, we found no significant change in weekly RTA rates after adjustment for seasonality and underlying temporal trend (rate ratio 1·01, 95% CI 0·94–1·08; p=0.77) or after adjustment for seasonality, the underlying temporal trend, and the driver characteristics of age, sex, and socioeconomic deprivation (1·00, 0·96–1·06; p=0·73). Relative to RTAs in England and Wales, where the reduction in BAC limit for drivers did not occur, we found a 7% increase in weekly RTA rates in Scotland after this reduction in BAC limit for drivers (1·07, 1·02–1·13; p=0·007 in the fully-adjusted model). Similar findings were observed for serious or fatal RTAs and single-vehicle night-time RTAs. The change in legislation in Scotland was associated with no change in alcohol consumption, measured by per-capita off-trade sales (−0·3%, −1·7 to 1·1; p=0·71), but a 0·7% decrease in alcohol consumption measured by per-capita on-trade sales (−0·7%, −0·8 to −0·5; p<0·0001). Interpretation: Lowering the driving BAC limit to 0·05 g/dL from 0·08 g/dL in Scotland was not associated with a reduction in RTAs, but this change was associated with a small reduction in per-capita alcohol consumption from on-trade alcohol sales. One plausible explanation is that the legislative change was not suitably enforced—for example with random breath testing measures. Our findings suggest that changing the legal BAC limit for drivers in isolation does not improve RTA outcomes. These findings have significant policy implications internationally as several countries and jurisdictions consider a similar reduction in the BAC limit for drivers

    Analysis of Fcγ receptor haplotypes in rheumatoid arthritis: FCGR3A remains a major susceptibility gene at this locus, with an additional contribution from FCGR3B

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    The Fcγ receptors play important roles in the initiation and regulation of many immunological and inflammatory processes, and genetic variants (FCGR) have been associated with numerous autoimmune and infectious diseases. The data in rheumatoid arthritis (RA) are conflicting and we previously demonstrated an association between FCGR3A and RA. In view of the close molecular proximity with FCGR2A, FCGR2B and FCGR3B, additional polymorphisms within these genes and FCGR haplotypes were examined to refine the extent of association with RA. Biallelic polymorphisms in FCGR2A, FCGR2B and FCGR3B were examined for association with RA in two well characterized UK Caucasian and North Indian/Pakistani cohorts, in which FCGR3A genotyping had previously been undertaken. Haplotype frequencies and linkage disequilibrium were estimated across the FCGR locus and a model-free analysis was performed to determine association with RA. This was followed by regression analysis, allowing for phase uncertainty, to identify the particular haplotype(s) that influences disease risk. Our results reveal that FCGR2A, FCGR2B and FCGR3B were not associated with RA. The haplotype with the strongest association with RA susceptibility was the FCGR3A–FCGR3B 158V-NA2 haplotype (odds ratio 3.18, 95% confidence interval 1.13–8.92 [P = 0.03] for homozygotes compared with all genotypes). The association was stronger in the presence of nodules (odds ratio 5.03, 95% confidence interval 1.44–17.56; P = 0.01). This haplotype was also more common in North Indian/Pakistani RA patients than in control individuals, but not significantly so. Logistic regression analyses suggested that FCGR3A remained the most significant gene at this locus. The increased association with an FCGR3A–FCGR3B haplotype suggests that other polymorphic variants within FCGR3A or FCGR3B, or in linkage disequilibrium with this haplotype, may additionally contribute to disease pathogenesis

    Technical Bulletins: Maintenance of Effort for Gas Tax Continues

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    The maintenance of effort provision in the legislation that increased the state gasoline tax in 1985 by three cents remained in effect for the Fiscal Year 1986-87
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