2,454 research outputs found

    Effectiveness of habitat management for improving grey partridge populations: a BACI experimental assessment

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    We assessed the impact of field division (4 m bare ground strips within wheat fields) and food supplementation (supplied through grain feeders) on grey partridge Perdix perdix L. populations using six–year ‘before–after’/'control–impact’ (BACI) experiments. We did not detect any convincing positive effects of either of these two schemes on partridge pair density and reproductive success. Increases in pair densities were similar on managed and control areas, and contrasting results were found between some sites. No consistent pattern was observed between reproductive success and feeding intensity. Our studies highlight the need for field experiments at farm–scale to test the effectiveness of management measures. We conclude that, in the context in which they are applied, management techniques directed towards increasing partridge density do not systematically provide the desired outcome. We develop our point of view about management in the Discussion

    The Boy from 6B: How Only Murders in the Building Created Groundbreaking Television

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    Non-disabled actors continue to be cast over disabled actors to portray disabled characters, and disabled storylines are told from an able-bodied perspective. This paper explores how Only Murders in the Building set an example for approaching projects featuring disabled actors and roles while maintaining a complex storyline in the episode titled The Boy from 6B (2021). Analyzing this episode through the lens of the classical idea of anmut shows how it subverted the typical viewing experience of watching a storyline that features disabled characters from an able-bodied perspective. Anmut, as a rhetorical concept, recognizes that the value of physical characteristics is socially constructed; a body can be just as desirable in one cultural setting as it can be undesirable in another. To illustrate this point, anmut creates the space for reconsidering disability by bringing social reactions and underlying assumptions about the human body and physical diversity to the forefront. Only Murders utilized this concept in “The Boy from 6B” by casting a deaf actor to play a deaf character and placing the viewer in the character’s world by removing their sense of hearing and their reliance on sound. The result is a more powerful connection between the viewer and the disabled character. Further, when compared to the movie Music (2020), directed by singer Sia—which features a disabled protagonist—Only Murders stands out by reattributing complexity to a community that is often portrayed reductively and by asking the audience to step, for thirty-one minutes, out of their abled body

    Dispersive Optical Interface Based on Nanofiber-Trapped Atoms

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    We dispersively interface an ensemble of one thousand atoms trapped in the evanescent field surrounding a tapered optical nanofiber. This method relies on the azimuthally-asymmetric coupling of the ensemble with the evanescent field of an off-resonant probe beam, transmitted through the nanofiber. The resulting birefringence and dispersion are significant; we observe a phase shift per atom of \sim\,1\,mrad at a detuning of six times the natural linewidth, corresponding to an effective resonant optical density per atom of 0.027. Moreover, we utilize this strong dispersion to non-destructively determine the number of atoms.Comment: 4 pages, 4 figure

    Field Oriented Sliding Mode Control of Surface-Mounted Permanent Magnet AC Motors: Theory and Applications to Electrified Vehicles

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    Permanent magnet ac motors have been extensively utilized for adjustable-speed traction motor drives, due to their inherent advantages including higher power density, superior efficiency and reliability, more precise and rapid torque control, larger power factor, longer bearing, and insulation life-time. Without any proportional-and-integral (PI) controllers, this paper introduces novel first- and higher-order field-oriented sliding mode control schemes. Compared with the traditional PI-based vector control techniques, it is shown that the proposed field oriented sliding mode control methods improve the dynamic torque and speed response, and enhance the robustness to parameter variations, modeling uncertainties, and external load perturbations. While both first- and higher-order controllers display excellent performance, computer simulations show that the higher-order field-oriented sliding mode scheme offers better performance by reducing the chattering phenomenon, which is presented in the first-order scheme. The higher-order field-oriented sliding mode controller, based on the hierarchical use of supertwisting algorithm, is then implemented with a Texas Instruments TMS320F28335 DSP hardware platform to prototype the surface-mounted permanent magnet ac motor drive. Last, computer simulation studies demonstrate that the proposed field-oriented sliding mode control approach is able to effectively meet the speed and torque requirements of a heavy-duty electrified vehicle during the EPA urban driving schedule

    The ALTCRISS project on board the International Space Station

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    The Altcriss project aims to perform a long term survey of the radiation environment on board the International Space Station. Measurements are being performed with active and passive devices in different locations and orientations of the Russian segment of the station. The goal is to perform a detailed evaluation of the differences in particle fluence and nuclear composition due to different shielding material and attitude of the station. The Sileye-3/Alteino detector is used to identify nuclei up to Iron in the energy range above 60 MeV/n. Several passive dosimeters (TLDs, CR39) are also placed in the same location of Sileye-3 detector. Polyethylene shielding is periodically interposed in front of the detectors to evaluate the effectiveness of shielding on the nuclear component of the cosmic radiation. The project was submitted to ESA in reply to the AO in the Life and Physical Science of 2004 and data taking began in December 2005. Dosimeters and data cards are rotated every six months: up to now three launches of dosimeters and data cards have been performed and have been returned with the end of expedition 12 and 13.Comment: Accepted for publication on Advances in Space Research http://dx.doi.org/10.1016/j.asr.2007.04.03

    Fatty acid concentrations in synchronous cultures ofChlorella pyrenoidosa, grown in the presence and absence of glucose

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    Total cellular fatty acids, of a high‐temperature strain ofChlorella pyrenoidosa, were measured during a synchronous growth cycle in continuous light in the presence and absence of glucose.The fatty acid composition, consisting of saturated monoenoic, dienoic, and trienoic C16 and C18 fatty acids, remained essentially the same whether or not the cells were grown on glucose.Nearly all of the fatty acids increased irregularly in concentration during the growth cycle, showing a periodism during the prenuclear and cell‐division stages of growth. Cultures exposed to glucose showed a more pronounced drop in the concentration of most of the fatty acids during both stages.None of the fatty acid concentrations, some of which have been implicated in the Hill reaction of a number of photosynthetic organisms, reflected the periodism in photosynthetic activity which was previously observed during the synchronous growth cycle of this organism.The changes in fatty acid concentration are discussed with relation to concurrent metabolic and cytological changes during cell maturation in this organism.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141363/1/lipd0381.pd

    Optical interface created by laser-cooled atoms trapped in the evanescent field surrounding an optical nanofiber

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    Trapping and optically interfacing laser-cooled neutral atoms is an essential requirement for their use in advanced quantum technologies. Here we simultaneously realize both of these tasks with cesium atoms interacting with a multi-color evanescent field surrounding an optical nanofiber. The atoms are localized in a one-dimensional optical lattice about 200 nm above the nanofiber surface and can be efficiently interrogated with a resonant light field sent through the nanofiber. Our technique opens the route towards the direct integration of laser-cooled atomic ensembles within fiber networks, an important prerequisite for large scale quantum communication schemes. Moreover, it is ideally suited to the realization of hybrid quantum systems that combine atoms with, e.g., solid state quantum devices
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