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101.
Barbara J. Meyer Brin F. S. Grenyer Trevor Crowe Alice J. Owen Elizabeth M. Grigonis-Deane Peter R. C. Howe 《Lipids》2013,48(9):863-868
The aim of this study was to determine if changes in omega‐3 polyunsaturated fatty acid status following tuna oil supplementation correlated with changes in scores of depression. A total of 95 volunteers receiving treatment for major depression were randomised to consume 8 × 1 g capsules per day of HiDHA (2 g DHA, 0.6 g EPA and 10 mg Vitamin E) or olive oil (placebo) for 16 weeks, whilst undergoing weekly counseling sessions by trained clinical psychologists using a standard empirically validated psychotherapy. Depression status was assessed using the 17 item Hamilton rating scale for depression and the Beck Depression Inventory by a psychodiagnostician who was blind to the treatment. Blood was taken at baseline and 16 weeks (n = 48) for measurement of erythrocyte fatty acids. With HiDHA supplementation, erythrocyte DHA content rose from 4.1 ± 0.2 to 7.9 ± 0.4 % (mean ± SEM, p < 0.001) of total fatty acids but did not change (4.0 ± 0.2 to 4.1 ± 0.2 %) in the olive oil group. The mean changes in scores of depression did not differ significantly between the two groups (?12.2 ± 2.1 for tuna oil and ?14.4 ± 2.3 for olive oil). However, analysis of covariance showed that in the fish oil group there was a significant correlation (r = ?0.51) between the change in erythrocyte DHA and the change in scores of depression (p < 0.05). Further study of the relationship between DHA and depression is warranted. 相似文献
102.
Mark Woh Yuan Lin Sangwon Seo Scott Mahlke Trevor Mudge 《Journal of Signal Processing Systems》2011,63(1):83-94
Commercial and research work in the field of software defined radio (SDR) has produced designs which have been able to deliver
the efficiency and computational power needed to process 3G wireless technologies. Though efficient 3G processing has been
achieved by these designs, next generation 4G SDR technology requires 10–1000x more computational performance but limits the
power budget increase to 2–5x. In this paper, we present a breakdown of the major 4G kernels and analyze two methods of increasing
performance and reducing power consumption. Specifically, we consider the effect of SIMD width and reduction in number of
register file accesses on the performance and energy consumption of a SDR architecture, SODA. We show that by increasing SIMD
width we can gain almost 2–8x performance increase while increasing total energy used by 1–2x for different SIMD widths. We
also show that by reducing SIMD register accesses we can reduce the total energy used by 5–20% for the 4G kernels. 相似文献
103.
104.
A techno-economic model of an autonomous wave-powered desalination plant is developed and indicates that fresh water can be produced for as little as £0.45/m3. The advantages of an autonomous wave-powered desalination plant are also discussed indicating that the real value of the system is enhanced due to its flexibility for deployment and reduced environmental impact. The modelled plant consists of the Oyster wave energy converter, conventional reverse osmosis membranes and a pressure exchanger–intensifier for energy recovery. A time-domain model of the plant is produced using wave-tank experimentation to calibrate the model of Oyster, manufacturer's data for the model of the reverse osmosis membranes and a hydraulic model of the pressure exchanger–intensifier. The economic model of the plant uses best-estimate cost data which are reduced to annualised costs to facilitate the calculation of the cost of water. Finally, the barriers to the deployment of this technology are discussed, but they are not considered insurmountable. 相似文献
105.
Summarizes background and selected research evidence with regard to the question of different standards of male and female "mental health." Recent studies, specifically those on the effects of gender-role-incongruent behavior on the perception of maladjustment, are outlined. These studies support the classic study of I. Broverman et al (see record 1970-06951-001), in which a double standard of male vs female mental health was alleged—females judged as maladjusted or "sick" when they exhibit gender-incongruent behavior. The issue of whether the androgyny concept should serve as a model of mental health or adjustment is discussed. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
106.
Near-tip displacement fields of a creep crack which exhibited moderate deflection from its initially mode I condition have been measured using the stereoimaging technique. From the measured displacement fields, near-tip strains and crack opening displacements (CODs) are obtained and compared with existing asymptotic solutions for stationary, deflected cracks. The comparison reveals that the near-tip strain field and CODs of a stationary deflected creep crack in stainless steel (creep exponent of 8) are of the Riedel-Rice type. The degree of mode mixity is also adequately predicted for the deflected crack. The results for stainless steel are compared with previous results for a glass-ceramic (creep exponent of 1.5), to assess the range of applicability of the RR field. Discrepancies between theory and experiment are discussed in terms of the dominant creep mechanism, which is dislocation creep for the stainless steel and grain boundary sliding for the glass-ceramic. 相似文献
107.
The utility of mass spectrometry as a technique for the characterisation of polymeric formulations is discussed in general terms. The use of thermal techniques in which sufficient energy is given to the system to liberate volatile components of the formulation and, in some cases, to induce small amounts of polymer degradation, is described. Results obtained using this technique for a variety of polymer systems are discussed and the advantages of using this approach outlined. Recent developments in field desorption-mass spectrometry for the direct characterisation of modern polymer systems are discussed and some early results presented. 相似文献
108.
109.
An Integrated DSS for Groundwater Management Based on Remote Sensing. The Case of a Semi-arid Aquifer in Morocco 总被引:1,自引:0,他引:1
Michel Le Page B. Berjamy Y. Fakir F. Bourgin L. Jarlan A. Abourida M. Benrhanem G. Jacob M. Huber F. Sghrer V. Simonneaux G. Chehbouni 《Water Resources Management》2012,26(11):3209-3230
A Decision Support System has been set up as the result of a fruitful cooperation between several public and research institutions in the framework of a large cooperation program. The DSS aims to compare spatially and temporally sectorial water demands of the Haouz-Mejjate plain (Morocco) in regard to available surface and groundwater resources. It is composed of a tool for satellite estimation of Agricultural Water Demand (SAMIR), a tool for integrated water resources planning (WEAP) and a groundwater model (MODFLOW) each of them relying on a common Geographical Information System not described here. The DSS is operating on a monthly time scale. Agricultural water demand accounts for about 80?% of the total demand. In areas where groundwater abstraction is difficult to quantify by direct methods, multitemporal remote sensing associated to the FAO methodology is a simple and efficient alternative to estimate Evapotranspiration (ET). In this work, a monthly estimate of ET from irrigated areas is derived from freely available MODIS NDVI for the 2001?C2009 period. An important part of the paper deals with the validation of these estimates with eddy covariance flux measurements installed on different irrigated crops of the region. Results are satisfactory with a minus 6.5?% error per year on the monthly time scale. This preprocessing allows to dichotomize irrigated versus non-irrigated areas, and then, to estimate groundwater abstraction in subareas distinguishing by their operating modes: traditional, dam or privately irrigated. A dynamic linkage between MODFLOW and WEAP transfers the results of one model as input data to the other. The model restitutes both spatial and temporal variations in head charges and allows the calculation of the ground water balance. After calibration, piezometric validation is acceptable for the majority of the 21 head control points. 相似文献
110.
Ronald Machaka Rudolph M. Erasmus Trevor E. Derry 《Diamond and Related Materials》2010,19(10):1131-1134
The structural modifications of polycrystalline hexagonal boron nitride implanted with He+ beams at energies between 200 keV and 1.2 MeV to fluences of 1.0 × 1017 ions cm? 2 were investigated using micro-Raman spectroscopy. The measured Raman spectra show evidence of implantation-induced structural transformations from the hexagonal phase to nanocrystalline cubic boron nitride, rhombohedral boron nitride and amorphous boron nitride phases. The first-order Longitudinal-Optical cubic boron nitride phonon was observed to be downshifted and asymmetrically broadened and this was explained using the spatial correlation model coupled with the high ion implantation-induced defect density. 相似文献