75 research outputs found

    Change of the plane of oscillation of a Foucault pendulum from simple pictures

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    The change of the plane of oscillation of a Foucault pendulum is calculated without using equations of motion, the Gauss-Bonnet theorem, parallel transport, or assumptions that are difficult to explain.Comment: 5 pages, 4 figure

    Dynamic scaling for 2D superconductors, Josephson junction arrays and superfluids

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    The value of the dynamic critical exponent zz is studied for two-dimensional superconducting, superfluid, and Josephson Junction array systems in zero magnetic field via the Fisher-Fisher-Huse dynamic scaling. We find z≃5.6±0.3z\simeq5.6\pm0.3, a relatively large value indicative of non-diffusive dynamics. Universality of the scaling function is tested and confirmed for the thinnest samples. We discuss the validity of the dynamic scaling analysis as well as the previous studies of the Kosterlitz-Thouless-Berezinskii transition in these systems, the results of which seem to be consistent with simple diffusion (z=2z=2). Further studies are discussed and encouraged.Comment: 19 pages in two-column RevTex, 8 embedded EPS figure

    I love being a midwife; it\u27s who I am : A Glaserian Grounded Theory Study of why midwives stay in midwifery

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    Aims and objectives: To understand why Western Australian (WA) midwives choose to remain in the profession. Background: Midwifery shortages and the inability to retain midwives in the midwifery profession is a global problem. The need for effective midwifery staff retention strategies to be implemented is therefore urgent, as is the need for evidence to inform those strategies. Design: Glaserian grounded theory (GT) methodology was used with constant comparative analysis. Methods: Fourteen midwives currently working clinically area were interviewed about why they remain in the profession. The GT process of constant comparative analysis resulted in an overarching core category emerging. The study is reported in accordance with Tong and associates’ (2007) Consolidated Criteria for Reporting Qualitative Research (COREQ). Results: The core category derived from the data was labelled—“I love being a midwife; it\u27s who I am.” The three major categories that underpin the core category are labelled as follows: “The people I work with make all the difference”; “I want to be ‘with woman’ so I can make a difference”; and “I feel a responsibility to pass on my skills, knowledge and wisdom to the next generation.” Conclusion: It emerged from the data that midwives’ ability to be “with woman” and the difference they feel they make to them, the people they work with and the opportunity to “grow” the next generation together underpin a compelling new middle‐range theory of the phenomenon of interest. Relevance to clinical practice: The theory that emerged and the insights it provides will be of interest to healthcare leaders, who may wish to use it to help develop midwifery workforce policy and practice, and by extension to optimise midwives’ job satisfaction, and facilitate the retention of midwives both locally and across Australia

    Environmental cues and constraints affecting the seasonality of dominant calanoid copepods in brackish, coastal waters: a case study of Acartia, Temora and Eurytemora species in the south-west Baltic

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    Information on physiological rates and tolerances helps one gain a cause-and-effect understanding of the role that some environmental (bottom–up) factors play in regulating the seasonality and productivity of key species. We combined the results of laboratory experiments on reproductive success and field time series data on adult abundance to explore factors controlling the seasonality of Acartia spp., Eurytemora affinis and Temora longicornis, key copepods of brackish, coastal and temperate environments. Patterns in laboratory and field data were discussed using a metabolic framework that included the effects of ‘controlling’, ‘masking’ and ‘directive’ environmental factors. Over a 5-year period, changes in adult abundance within two south-west Baltic field sites (Kiel Fjord Pier, 54°19â€Č89N, 10°09â€Č06E, 12–21 psu, and North/Baltic Sea Canal NOK, 54°20â€Č45N, 9°57â€Č02E, 4–10 psu) were evaluated with respect to changes in temperature, salinity, day length and chlorophyll a concentration. Acartia spp. dominated the copepod assemblage at both sites (up to 16,764 and 21,771 females m−3 at NOK and Pier) and was 4 to 10 times more abundant than E. affinis (to 2,939 m−3 at NOK) and T. longicornis (to 1,959 m−3 at Pier), respectively. Species-specific salinity tolerance explains differences in adult abundance between sampling sites whereas phenological differences among species are best explained by the influence of species-specific thermal windows and prey requirements supporting survival and egg production. Multiple intrinsic and extrinsic (environmental) factors influence the production of different egg types (normal and resting), regulate life-history strategies and influence match–mismatch dynamics

    Statistical Emulation of Winter Ambient Fine Particulate Matter Concentrations From Emission Changes in China

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    Air pollution exposure remains a leading public health problem in China. The use of chemical transport models to quantify the impacts of various emission changes on air quality is limited by their large computational demands. Machine learning models can emulate chemical transport models to provide computationally efficient predictions of outputs based on statistical associations with inputs. We developed novel emulators relating emission changes in five key anthropogenic sectors (residential, industry, land transport, agriculture, and power generation) to winter ambient fine particulate matter (PM2.5) concentrations across China. The emulators were optimized based on Gaussian process regressors with Matern kernels. The emulators predicted 99.9% of the variance in PM2.5 concentrations for a given input configuration of emission changes. PM2.5 concentrations are primarily sensitive to residential (51%–94% of first‐order sensitivity index), industrial (7%–31%), and agricultural emissions (0%–24%). Sensitivities of PM2.5 concentrations to land transport and power generation emissions are all under 5%, except in South West China where land transport emissions contributed 13%. The largest reduction in winter PM2.5 exposure for changes in the five emission sectors is by 68%–81%, down to 15.3–25.9 ÎŒg m−3, remaining above the World Health Organization annual guideline of 10 ÎŒg m−3. The greatest reductions in PM2.5 exposure are driven by reducing residential and industrial emissions, emphasizing the importance of emission reductions in these key sectors. We show that the annual National Air Quality Target of 35 ÎŒg m−3 is unlikely to be achieved during winter without strong emission reductions from the residential and industrial sectors

    Performance evaluation of primary care services for the treatment of tuberculosis

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    Objective Evaluating the performance of primary care services for the treatment of tuberculosis according to the assessment referential of health services (structure/process) in Cabedelo, a port city in the state of ParaĂ­ba. Method An evaluation quantitative, cross-sectional study, in which were carried out 117 interviews with health professionals using a structured instrument. The analysis was based on the construction of indicators using a standardized value for the reduced variable (z=1). Results The structural indicators showed regular performance for the following variables: professional training, access to record instruments and coordination with other services. The process indicators related to external actions and information about the disease had unsatisfactory performance. The directly observed treatment and the flows of reference/counter-reference had regular performance. Conclusion The focused professional qualification, the fragmentation of practices and the unsystematic home care constitute obstacles for carrying out actions aimed at providing expanded, continuous and resolute care

    Mon. Not. R. Astron. Soc. 354, 55--70 (2004) doi:10.1111/j.1365-2966.2004.08168.x Extracting cosmic microwave background polarization from satellite

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    We present the application of the fast independent component analysis (FASTICA) technique for blind component separation to polarized astrophysical emission. We study how the cosmic microwave background (CMB) polarized signal, consisting of E and B modes, can be extracted from maps affected by substantial contamination from diffuse Galactic foreground emission and instrumental noise. We implement Monte Carlo chains varying the CMB and noise realizations in order to asses the average capabilities of the algorithm and their variance. We perform the analysis of all-sky maps simulated according to the Planck satellite capabilities, modelling the sky signal as a superposition of the CMB and of the existing simulated polarization templates of Galactic synchrotron. Our results indicate that the angular power spectrum of CMB E mode can be recovered on all scales up to # 1000, corresponding to the fourth acoustic oscillation, while the B-mode power spectrum can be detected, up to its turnover at # 100, if the ratio of tensor to scalar contributions to the temperature quadrupole exceeds 30 per cent. The power spectrum of the cross-correlation between total intensity and polarization, TE, can be recovered up to # 1200, corresponding to the seventh TE acoustic oscillation
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