573 research outputs found
Measurement of ÎS at COMPASS
The extraction of the strange quark contribution to the axial nucleon coupling ÎS from COMPASS data is reviewed. Both inclusive and semi-inclusive measurements are used. With inclusive data using SU(3) flavour symmetry one finds
ÎS = â0.08 ± 0.01(stat.) ± 0.02(syst.), whereas from semi-inclusive data one has ÎS = â0.02 ± 0.02(stat.) ± 0.02(syst.). This disagreement was previously ascribed to the lack of data in the low Bjorken x domain. The COMPASS results do not validate this explanation completely
Inside Ownership, Risk Sharing and Tobin's q -Ratios: Evidence from REITs
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73828/1/1540-6229.00070.pd
Direct and imagined contact moderates the effect of need for cognitive closure on attitudes towards women managers
This research investigated the relationship between individual preference for the need for cognitive closure (NCC) and attitudes towards women as managers and the moderating role of direct or imagined contact with women leaders. In two studies (total N = 369) collected in different countries and with different methods (Study 1: Italy, correlational; Study 2: U.S., experimental), it was found that the positive relationship between NCC and negative attitudes towards women as managers was moderated by the quality, but not the quantity of current or past direct contact experiences with women managers. In Study 1, employees with higher scores on NCC had more positive attitudes towards women managers when they had more positive work experience with women managers. In Study 2, those with higher NCC scores had less negative attitudes towards women as managers when they merely imagined (positive) contact with them (vs. a control group). These results advance the literature on the interaction between NCC and positive intergroup contact; theoretical and practical implications of NCC and positive intergroup contact are presented
A Chemical Strategy for the Preparation of Multimodified Peptide Imaging Probes
Multimodality probes appear of great interest for innovative imaging applications in disease diagnosis. Herein, we present a chemical strategy enabling site-specific doublemodification and cyclization of a peptide probe exploiting native chemical ligation (NCL) and thiol-maleimide addition. The synthetic strategy is straightforward and of general applicability for the development of double-labeled peptide multimodality probes
Analysis of the independent power of age-related, anthropometric and mechanical factors as determinants of the structure of radius and tibia in normal adults: a pQCT study
To compare the independent influence of mechanical and non-mechanical factors on bone features, multiple regression analyses were performed between pQCT indicators of radius and tibia bone mass, mineralization, design and strength as determined variables, and age or time since menopause (TMP), body mass, bone length and regional musclesâ areas as selected determinant factors, in Caucasian, physically active, untrained healthy men and pre- and post-menopausal women. In men and pre-menopausal women, the strongest influences were exerted by muscle area on radial features and by both muscle area and bone length on the tibia. Only for women, was body mass a significant factor for tibia traits. In men and pre-menopausal women, mass/design/strength indicators depended more strongly on the selected determinants than the cortical vBMD did (p<0.01-0.001 vs n.s.), regardless of age. However, TMP was an additional factor for both bones (p<0.01-0.001). The selected mechanical factors (muscle size, bone lengths) were more relevant than age/TMP or body weight to the development of allometrically-related bone properties (mass/design/strength), yet not to bone tissue âqualityâ (cortical vBMD), suggesting a determinant, rather than determined role for cortical stiffness. While the mechanical impacts of muscles and bone levers on bone structure were comparable in men and pre-menopausal women, TMP exerted a stronger impact than allometric or mechanical factors on bone properties, including cortical vBMD.Fil: Reina, Paola Soledad. Universidad Nacional de Rosario. Facultad de Cs.medicas. Centro de Est.de Metabolismo Fosfocalcico; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Cointry, Gustavo Roberto. Universidad Nacional de Rosario. Facultad de Cs.medicas. Centro de Est.de Metabolismo Fosfocalcico; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Nocciolino, L.. Universidad Nacional de Rosario. Facultad de Cs.medicas. Centro de Est.de Metabolismo Fosfocalcico; ArgentinaFil: Feldman, Sara. Universidad Nacional de Rosario. Facultad de Cs.medicas; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Ferretti, Jose Luis. Universidad Nacional de Rosario. Facultad de Cs.medicas. Centro de Est.de Metabolismo Fosfocalcico; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Rittweger, J.. German Space Center. Institute of Aerospace Medicine; AlemaniaFil: Capozza, Ricardo Francisco. Universidad Nacional de Rosario. Facultad de Cs.medicas. Centro de Est.de Metabolismo Fosfocalcico; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentin
Realtime calibration of the A4 electromagnetic lead fluoride calorimeter
Sufficient energy resolution is the key issue for the calorimetry in particle
and nuclear physics. The calorimeter of the A4 parity violation experiment at
MAMI is a segmented calorimeter where the energy of an event is determined by
summing the signals of neighbouring channels. In this case the precise matching
of the individual modules is crucial to obtain a good energy resolution. We
have developped a calibration procedure for our total absorbing electromagnetic
calorimeter which consists of 1022 lead fluoride (PbF_2) crystals. This
procedure reconstructs the the single-module contributions to the events by
solving a linear system of equations, involving the inversion of a 1022 x
1022-matrix. The system has shown its functionality at beam energies between
300 and 1500 MeV and represents a new and fast method to keep the calorimeter
permanently in a well-calibrated state
A luminosity monitor for the A4 parity violation experiment at MAMI
A water Cherenkov luminosity monitor system with associated electronics has
been developed for the A4 parity violation experiment at MAMI. The detector
system measures the luminosity of the hydrogen target hit by the MAMI electron
beam and monitors the stability of the liquid hydrogen target. Both is required
for the precise study of the count rate asymmetries in the scattering of
longitudinally polarized electrons on unpolarized protons. Any helicity
correlated fluctuation of the target density leads to false asymmetries. The
performance of the luminosity monitor, investigated in about 2000 hours with
electron beam, and the results of its application in the A4 experiment are
presented.Comment: 22 pages, 12 figures, submitted to NIM
Meagre effects of disuse on the human fibula are not explained by bone size or geometry
Summary
Fibula response to disuse is unknown; we assessed fibula bone in spinal cord injury (SCI) patients and able-bodied counterparts. Group differences were smaller than in the neighbouring tibia which could not be explained by bone geometry. Differential adaptation of the shank bones may indicate previously unknown mechanoadaptive behaviours of bone.
Introduction
The fibula supports only a small and highly variable proportion of shank compressive load (â8 to +19 %), and little is known about other kinds of stresses. Hence, whilst effects of habitual loading on tibia are well-known, fibula response to disuse is difficult to predict.
Methods
Therefore, we assessed fibular bone strength using peripheral quantitative computed tomography (pQCT) at 5 % increments from 5 to 90 % distal-proximal tibia length in nine participants with long-term spinal cord injury (SCI; age 39.2 ± 6.2 years, time since injury 17.8 ± 7.4 years), representing a cross-sectional model of long-term disuse and in nine able-bodied counterparts of similar age (39.6 ± 7.8 years), height and mass.
Results
There was no group difference in diaphyseal fibula total bone mineral content (BMC) (P = 0.22, 95 % CIs -7.4 % to -13.4 % and +10.9 % to +19.2 %). Site by group interactions (P < 0.001) revealed 27 and 22 % lower BMC in SCI at 5 and 90 % (epiphyseal) sites only. Cortical bone geometry differed at mid and distal diaphysis, with lower endocortical circumference and greater cortical thickness in SCI than able-bodied participants in this region only (interactions both P < 0.01). Tibia bone strength was also assessed; bone by group interactions showed smaller group differences in fibula than tibia for all bone parameters, with opposing effects on distal diaphysis geometry in the two bones (all Ps < 0.001).
Conclusions
These results suggest that the structure of the fibula diaphysis is not heavily influenced by compressive loading, and only mid and distal diaphysis are influenced by bending and/or torsional loads. The fibula is less influenced by disuse than the tibia, which cannot satisfactorily be explained by differences in bone geometry or relative changes in habitual loading in disuse. Biomechanical study of the shank loading environment may give new information pertaining to factors influencing bone mechanoadaptation
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