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排序方式: 共有386条查询结果,搜索用时 15 毫秒
91.
Orn-uma Polpanich Steve W. Lyon Chayanis Krittasudthacheewa Angela L. Bush Eric Kemp-Benedict 《国际水资源开发杂志》2017,33(6):1020-1040
Little is done to connect hydrological modelling with stakeholder participation. This study incorporates agricultural development and climatic changes within the Water Evaluation and Planning hydrological model. This is done with a participatory approach involving four scenario workshops, 400 household surveys and two focus group discussions in the period of 2010–2012 for the ungauged Huai Sai Bat sub-basin as a case study in the Mekong region. The modelling results indicate future increased streamflow during the wet (monsoon) season in response to shifts in the regional climate. Modelled land-use and management changes brought about large unmet water demands, primarily in the dry season. 相似文献
92.
Stephen F. Bush 《Frontiers of Computer Science in China》2011,5(3):316-326
A safe and reliable in vivo nanoscale communication network will be of great benefit for medical diagnosis and monitoring as well as medical implant
communication. This review article provides a brief introduction to nanoscale and molecular networking in general and provides
opinions on the role of active networking for in vivo nanoscale information transport. While there are many in vivo communication mechanisms that can be leveraged, for example, forms of cell signaling, gap junctions, calcium and ion signaling,
and circulatory borne communication, this review examines two in particular: molecular motor transport and neuronal information
communication. Molecular motors transport molecules representing information and neural coding operates by means of the action
potential; these mechanisms are reviewed within the theoretical framework of an active network. This review suggests that
an active networking paradigm is necessary at the nanoscale along with a new communication constraint, namely, minimizing
the communication impact upon the living environment. The goal is to assemble efficient nanoscale and molecular communication
channels while minimizing disruption to the host organism. 相似文献
93.
The identification of genes that influence the risk of common, complex disease primarily through interactions with other genes and environmental factors remains a statistical and computational challenge in genetic epidemiology. This challenge is partly due to the limitations of parametric statistical methods for detecting genetic effects that are dependent solely or partially on interactions. We have previously introduced a genetic programming neural network (GPNN) as a method for optimizing the architecture of a neural network to improve the identification of genetic and gene-environment combinations associated with disease risk. Previous empirical studies suggest GPNN has excellent power for identifying gene-gene and gene-environment interactions. The goal of this study was to compare the power of GPNN to stepwise logistic regression (SLR) and classification and regression trees (CART) for identifying gene-gene and gene-environment interactions. SLR and CART are standard methods of analysis for genetic association studies. Using simulated data, we show that GPNN has higher power to identify gene-gene and gene-environment interactions than SLR and CART. These results indicate that GPNN may be a useful pattern recognition approach for detecting gene-gene and gene-environment interactions in studies of human disease. 相似文献
94.
Mary A A Bush Chantal Martineau Janet A Pronk Danielle Brulé 《Revue canadienne de la pratique et de la recherche en diététique》2007,68(2):92-96
This article outlines the processes undertaken to revise Canada's Food Guide and shares the updated science that underpins the dietary pattern. The Dietary Reference Intakes provide updated nutrient requirement values and better tools for dietary assessment and planning. Alignment with this updated science was an important component of defining and communicating accurate dietary guidance for Canada. Ensuring that stakeholders had access to the updated review of requirements led to the development of the text Dietary Reference Intakes: The Essential Guide to Nutrient Requirements. Equally important was ensuring that stakeholders were provided opportunity to influence the approach taken to giving dietary guidance, both content and the elements of the final package. A combination of research, consultation and expert advice guided the process to the release of Eating Well with Canada's Food Guide (2007). 相似文献
95.
Shreela V Sharma Jill A Bush Andrew J Lorino Mark Knoblauch Diana Abuamer Gabe Blog Dave Bertman 《Journal of the International Society of Sports Nutrition》2008,5(1):9
Background
Cardiovascular disease (CVD) is the leading cause of death in the United States. Diets high in fat, especially saturated fat, are often linked to obesity, hypertension and hypercholesterolemia, all risk factors for CVD. The purpose of this study was to determine the association between diet and CVD risk factors in members of a university marching band, dance team and cheer squad. 相似文献96.
97.
Kessy F. Kilulya Titus A. M. Msagati Bhekie B. Mamba J. Catherine Ngila Tamara Bush 《木材化学与工艺学杂志》2013,33(3):253-267
Abstract Lipophilic extractives in dissolving pulp are still a big concern for pulp industries due to their detrimental effect on the quality of pulp. Since lipophilic extractives remaining in pulp are trapped in low-accessible fiber structures, effective extraction methods need to be established for studying their fate in the process. A simple, ultrasonic, solid liquid extraction established in this study was found to be more effective in capturing extractive residues in all “elemental chlorine-free” bleaching stages. Its efficiency was dependent on the extraction temperature, time, and solvent composition. A linearly correlated removal pattern of sterols and unsaturated fatty acids by the bleaching sequence was observed. It was further found that the bleaching combination did not fully remove lipophilic extractives. This study suggests an opportunity to explore ultrasonication-based extraction as an effective extraction procedure prior to gas chromatography mass spectrometry analysis for monitoring extractives in pulp. 相似文献
98.
Amanda J. Keown James J.-W. Lee Mark B. Bush 《Journal of materials science. Materials in medicine》2012,23(12):2847-2856
Despite the durability of human teeth, which are able to withstand repeated loading while maintaining form and function, they are still susceptible to fracture. We focus here on longitudinal fracture in molar teeth??channel-like cracks that run along the enamel sidewall of the tooth between the gum line (cemento-enamel junction??CEJ) and the occlusal surface. Such fractures can often be painful and necessitate costly restorative work. The following study describes fracture experiments made on molar teeth of humans in which the molars are placed under axial compressive load using a hard indenting plate in order to induce longitudinal cracks in the enamel. Observed damage modes include fractures originating in the occlusal region (??radial-median cracks??) and fractures emanating from the margin of the enamel in the region of the CEJ (??margin cracks??), as well as ??spalling?? of enamel (the linking of longitudinal cracks). The loading conditions that govern fracture behavior in enamel are reported and observations made of the evolution of fracture as the load is increased. Relatively low loads were required to induce observable crack initiation??approximately 100?N for radial-median cracks and 200?N for margin cracks??both of which are less than the reported maximum biting force on a single molar tooth of several hundred Newtons. Unstable crack growth was observed to take place soon after and occurred at loads lower than those calculated by the current fracture models. Multiple cracks were observed on a single cusp, their interactions influencing crack growth behavior. The majority of the teeth tested in this study were noted to exhibit margin cracks prior to compression testing, which were apparently formed during the functional lifetime of the tooth. Such teeth were still able to withstand additional loading prior to catastrophic fracture, highlighting the remarkable damage containment capabilities of the natural tooth structure. 相似文献
99.
Campuzano I Bush MF Robinson CV Beaumont C Richardson K Kim H Kim HI 《Analytical chemistry》2012,84(2):1026-1033
We present the use of drug-like molecules as a traveling wave (T-wave) ion mobility (IM) calibration sample set, covering the m/z range of 122.1-609.3, the nitrogen collision cross-section (Ω(N(2))) range of 124.5-254.3 ?(2) and the helium collision cross-section (Ω(He)) range of 63.0-178.8 ?(2). Absolute Ω(N(2)) and Ω(He) values for the drug-like calibrants and two diastereomers were measured using a drift-tube instrument with radio frequency (RF) ion confinement. T-wave drift-times for the protonated diastereomers betamethasone and dexamethasone are reproducibly different. Calibration of these drift-times yields T-wave Ω(N(2)) values of 189.4 and 190.4 ?(2), respectively. These results demonstrate the ability of T-wave IM spectrometry to differentiate diastereomers differing in Ω(N(2)) value by only 1 ?(2), even though the resolution of these IM experiments were ~40 (Ω/ΔΩ). Demonstrated through density functional theory optimized geometries and ionic electrostatic surface potential analysis, the small but measurable mobility difference between the two diastereomers is mainly due to short-range van der Waals interactions with the neutral buffer gas and not long-range charge-induced dipole interactions. The experimental RF-confining drift-tube and T-wave Ω(N(2)) values were also evaluated using a nitrogen based trajectory method, optimized for T-wave operating temperature and pressures, incorporating additional scaling factors to the Lennard-Jones potentials. Experimental Ω(He) values were also compared to the original and optimized helium based trajectory methods. 相似文献
100.
Acid-volatile sulfide oxidation in coastal flood plain drains: iron-sulfur cycling and effects on water quality 总被引:1,自引:0,他引:1
The effect of acid-volatile sulfide (AVS) oxidation on Fe-S cycling and water quality in coastal flood plain drains from acid-sulfate soil landscapes was examined using natural sediments and synthetic iron monosulfide. Oxidation of AVS occurred rapidly (half-time < or = 1 h) and produced elemental sulfur (S8(0)(s)) and iron oxyhydroxide (FeOOH(s)). The initial rapid AVS oxidation process occurred without significant acidification or changes to the aqueous-phase composition. Severe acidification (pH < 4) occurred only once S8(0)(s) began to oxidize to SO4 (within 2-3 days of the initial AVS oxidation). Our results demonstrate, for the first time with natural sediments, a significant pH-buffered (near-neutral) AVS oxidation step with the trigger to acidification being the oxidation of S8(0)(s). Acidification resulted in the pH-dependent release of large amounts of Al, Mn, Ni, and Zn even though the sediment metal content was low. 相似文献