12,664 research outputs found

    Updated analysis of the dynamical relation between asteroid 2003 EH1 and comets C/1490 Y1 and C/1385 U1

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    The asteroid 2003 EH1, proposed as the parent body of the Quadrantid meteor shower, is thought to be the remnant of a past cometary object, tentatively identified with the historical comets C/1490 Y1 and C/1385 U1. In the present work we use recovery astrometry to extend the observed arc of 2003 EH1 from 10 months to about 5 years, enough to exclude the proposed direct relationship of the asteroid with both of the comets.Comment: Submitted to Monthly Notices of the RAS Letters Updated with a new table and other minor change

    High-Efficiency Screening of Monoclonal Antibodies for Membrane Protein Crystallography

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    Determination of crystal structures of membrane proteins is often limited by difficulties obtaining crystals diffracting to high resolution. Co-crystallization with Fab fragments of monoclonal antibodies has been reported to improve diffraction of membrane proteins crystals. However, it is not simple to generate useful monoclonal antibodies for membrane protein crystallography. In this report, we present an optimized process for efficient screening from immunization to final validation of monoclonal antibody for membrane protein crystallography

    Validation of Chinese Multidimensional Depression Assessment Scale (MDAS) in Inner Mongolia pregnant women and risk factors of antenatal depression in Inner Mongolia in the era of one-child policy

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    BACKGROUND:Pregnancy involves physiological changes in reproductive and endocrine systems, and social role changes that can increase the risk of mental health problems. In China, greater emphasis has been given to postpartum depression and its negative impact on infant development. This study examined depression in pregnant women in Inner Mongolia, who are under the influence of cultural values of collectivism and social factors specific to China. Chinese society adheres firmly to traditional values, while market reform, birth-control policy, together with high parental investment in childcare and rearing construct a unique and sometimes unfavorable environment for Chinese women that may influence their depression expression. THE AIMS OF THIS STUDY ARE TWOFOLD:First, it validated the Chinese Multidimensional Depression Assessment Scale (MDAS), a holistic self-report questionnaire measuring depression severity in four domains of depression-emotional, somatic, cognitive and interpersonal in pregnant women in Inner Mongolia; second, it examined the influences of demographic characteristics (including age, education and employment), pregnancy characteristics (week of gestation, first pregnancy), self-esteem, social support, social activity, work stress, and work-family balance on depression. METHODS:A total of 234 pregnant women, mostly in their third trimester, were recruited in an antenatal hospital in Inner Mongolia and self-reported questionnaires were completed. RESULTS:Using Confirmatory factor analysis (CFA), MDAS gave rise to a best-fit four-factor model corresponding to each subscale when it was first developed. MDAS also reported high Cronbach's alpha (0.96) and good convergent validity. Using hierarchical multiple linear regressions with significant demographic variables controlled for, self-esteem, work-family conflict, and social support were found to be significant predictors for depression. CONCLUSIONS:MDAS is a valid scale to be used with Chinese pregnant women, especially in more collectivistic geographical areas. Risk factors specific to the Chinese context add insights to the experience of antenatal depression in China and contribute to understanding depression in from a global mental health perspective

    Older people’s experiences of living with, responding to and managing sensory loss

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    (1) Background: Ageing is associated with a decline in sensory function (sight, hearing, taste, touch and smell), which play an important role in the maintenance of an older person’s health, independence and well-being. (2) Methods: This qualitative study obtained data through face-to-face semi-structured interviews with a convenience sample of thirteen community-dwelling adults 65 years and older. Themes were derived inductively, guided by semi-structured interviews. (3) Results: Twelve participants had two or more sensory impairments, mainly concurrent hearing and vision, which became apparent when a situation/individual alerted them to change/s occurring. They were less aware of impaired smell, taste and touch. Sensory changes impacted on important life functions, prompting many participants to take measured risks in maintaining their independence. Half (seven) of the participants lacked motivation to manage sensory function through goal-directed behaviour, taking remedial actions only when this was relevant to lifestyle preferences. (4) Con-clusions: Internal and/or external triggers of sensory changes did not generally motivate remedial action. Health professionals can help to improve older people’s attention to sensory impairment by routinely discussing sensory function with them, screening for sensory changes and facilitating early intervention and support

    Orbital Elements of Comet C/1490 Y1 and the Quadrantid shower

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    The Quadrantid shower, one of the most intense showers, has been observed at the beginning of January each year. However, the origin of the meteors is still unknown. It was Hasegawa (1979) who first suggested comet C/1490 Y1 to be the likely origin of the shower based on the historical records of East Asia. We analyse the records of Jo-Seon-Wang-Jo-Sil-Lok (the Annals of the Joseon Dynasty in ancient Korea) and calculate the preliminary orbital elements of comet C/1490 Y1 using a modified Gauss method. We find that comet C/1490 Y1 was a periodic one and its orbital path was very similar to that of the Quadrantid meteor stream. The determined orbital elements are perifocal passage time Tp=2265652.2983 days (7.8 Jan. 1491 in UT), perifocal distance q=0.769 AU, eccentricity e=0.747, semimajor axis a=3.04 AU, argument of the perifocus omega=164.03 degrees, longitude of ascending node Omega=283.00 degrees, and inclination i=70.22 degrees for the epoch of J2000.0. We, therefore, conclude that our result verifies the suggestion that the comet C/1490 Y1 is the origin of the Quandrantid meteor shower, but was a periodic comet. We dicuss a possible link between this comet and the asteroid 2003 EH1 as well.Comment: 7 pages, 2 figures, accepted for publication in MNRA

    Equilibrium and stability properties of a coupled two-component Bose-Einstein condensate

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    The equilibrium and stability properties of a coupled two-component BEC is studied using a variational method and the one-dimensional model of Williams and collaborators. The variational parameters are the population fraction, translation and scaling transformation of the condensate densities, assumed to have a Gaussian shape. We study the equilibrium and stability properties as a function of the strength of the laser field and the traps displacement. We find many branches of equilibrium configurations, with a host of critical points. In all cases, the signature of the onset of criticality is the collapse of a normal mode which is a linear combination of the out of phase translation and an in phase breathing oscillation of the condensate densities. Our calculations also indicate that we have symmetry breaking effects when the traps are not displacedComment: 13 pages,3 figure

    Wigner Crystals Phases in Bilayer Quantum Hall Systems

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    (This is a substantially shortened version of the original abstract:) The Wigner crystal phase diagram of the bilayer systems have been studied using variational methods. Five crystal phases are obtained. As the layer spacing increases, the system will undergo a sequence of phase transitions. A common feature of most bilayer Wigner crystals is that they have mixed (pseudo-spin) ferromagnetic and antiferromagnetic order.Comment: 19 figures. Figures will be provided upon request. Submitted in PRB in Nov 94

    Citizen Engagement Strategies

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    poster abstractThe project studied citizen engagement strategies, including Web 2.0 tools and traditional meetings, and provided recommendations to the City of Indianapolis. Citizen surveys, field observations, and best practice research of other US cities were conducted by 4 student interns from SPEA, Herron, and Journalism

    The Effect of Thermal History on Microstructural Evolution, Cold-Work Refinement and {\alpha}/\b{eta} Growth in Ti-6Al-4V Wire + Arc AM

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    Wire + arc additive manufacture (WAAM) is an attractive method for manufacturing large-scale aerospace components, however the microstructural changes that occur and the effect of interpass rolling are poorly understood. Therefore two fundamental studies were conducted: the first involved temperature measurement of a wrought dummy wall so that the microstructural changes in the heat affected zone (HAZ) could be related to the thermal cycle. This demonstrated that the white band in the microstructure corresponded to 825 C well below the beta-transus temperature and above this boundary the bi-modal substrate material was converted to lamellar. The second involved peening WAAM material along the side of a deposited wall before applying a typical WAAM thermal heat treatment. This showed that refinement occurred up to the first layer band in the microstructure and the smallest grains were observed just above this boundary at higher temperatures significant grain growth occurred. This study has provided the foundational understanding of microstructural changes that will facilitate future process developments.Comment: 15 Figures, 25 pages, Journal publicatio
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