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1.
This study investigates within-subject variations and associations of salivary viscosities and flow rates in a test panel of healthy adults. After several practice sessions, unstimulated and stimulated whole saliva samples were collected 5 times daily (at 0800, 1100, 1400, 1700, and 2000 h) from 30 university students. There was a significant within-subject variation in viscosity and flow rate of unstimulated saliva (P<0.001). Intra-item correlations were significantly different for salivary flow rates (r= 0.82 for unstimulated, r= 0.88 for stimulated, P< 0.001) and viscosity of unstimulated saliva (r= 0.54, P< 0.05), but viscosity of stimulated saliva was different in this respect. Our results indicate that there is a significant within-subject variation in viscosity of unstimulated saliva. 相似文献
2.
Matthew T. Martens Alexander J. Wall Greg G. Pyle Blair A. Wasylenko William A. Dew Robert H. Devlin Paul J. Blanchfield 《Journal of Great Lakes research》2014
Selective breeding of salmonid fishes for the purpose of commercial aquaculture has resulted in domesticated strains possessing a divergent physiological and behavioral phenotype from that of wild conspecifics. Freshwater production of rainbow trout (Oncorhynchus mykiss) has been occurring in regions of Lake Huron, Canada, for decades yet the growth and performance of domestic (aquaculture) versus wild (naturalized) strains are poorly understood. We conducted two trials to examine growth differences between size-matched wild and domestic strains of juvenile rainbow trout: (1) reared separately and fed to satiation; and (2) reared together and fed a reduced ration to induce competition. Additionally, we used bioenergetics models to assess strain-specific growth rates across a range of water temperatures (5, 10, 15 and 18 °C) as well as Lake Huron temperatures during the open-water season. Domestic rainbow trout showed a growth advantage throughout the 102 d trials, and by the end of the study had achieved a mass > two-fold that of the wild strain and had greater fork length, condition, and thermal growth coefficient (TGC) under both treatments. Rapid growth of domestic strain fish was achieved through the combination of enhanced feed consumption (by ~ 40%) and feeding efficiency (up to 60% lower feed conversion ratio) relative to wild fish. Divergence in growth rates between strains was most pronounced (> 3 ×) when modeled with Lake Huron open-water temperatures. We demonstrate that the growth and feed-conversion efficiency differ significantly between these two strains of rainbow trout under laboratory conditions, suggesting that differences could be even greater in nature. 相似文献
3.
Smy T. Tan L. Chan K. Tait R.N. Broughton J.N. Dew S.K. Brett M.J. 《Electron Devices, IEEE Transactions on》1998,45(7):1414-1425
Modified sputtering techniques, such as long throw sputtering, collimation, and ionized sputtering, have been proposed to improve VLSI topography bottom coverage by narrowing the angular distribution of the sputter flux at the substrate and reducing subsequent flux shadowing at the bottom of topography. This paper first investigates a number of unique aspects involved in the simulation of long throw sputter systems. In particular, time importance of inhomogeneous film density and nonunity sticking coefficients are addressed. The second part of the paper presents a simulation study of long throw sputtering, providing a comparison to collimated and standard sputtering systems. The simulations are performed using the SIMSPUD/SIMBAD ballistic deposition tool. SIMSPUD is used to study film uniformity over a 300-mm wafer and to generate angular distributions at the center and edge of the wafer. The ability of SIMBAD to simulate directed sputtering systems is verified by direct comparison to Ti films deposited into oxide trenches. The importance of modeling the film microstructure is demonstrated by comparison between cross-sectional SEM's micrograph for evaporation and modeling results, such as long throw sputtering with a variety of substrate/target spacings, typical “standard” as well as “collimated” systems. SEM's of overhang structures and simulations are also presented to demonstrate nonunity sticking during the co-sputtering of TiW 相似文献
4.
This paper describes the design and implementation of Mistral-3, a parallel solid odeller for distributed-memory multicomputers implementing algorithms for creating, ray tracing and incrementally updating octree-based spatial data structures. The system has been designed to be scalable and portable. Scalability is addressed by distributing the control of task and data management between all available processors and portability's solved by building software for the abstraction of a distributed-memory multicomputer. An object-oriented approach to the design is adopted to help produce a structured system. Results are presented showing Mistral-3 has made good use of up to 128 T800 transputers. It has been ported to transputer-and non-transputer-based multicomputers. 相似文献
5.
6.
Investigated 4 considerations about mathematics anxiety (MA): (a) the degree of MA experienced by men and women, (b) the internal consistency and test–retest reliabilities of 3 MA measures, (c) the relationship of MA instruments to each other, and (d) the relationship of MA to test anxiety and its worry and emotionality components. 769 college students' MA was measured by the Mathematics Anxiety Scale (MAS), the Anxiety Toward Mathematics Scale (ATMS), and the Mathematics Anxiety Rating Scale (MARS). Ss also completed the Test Anxiety Inventory. Results indicate nonequivalent internal consistency and test–retest reliability coefficients for the 3 MA measures, with the ATMS having the lowest coefficients. Small but significant gender differences were found on the MARS and MAS. The MA measures were moderately related to each other, and almost invariably, they were more closely related to each other than to test anxiety and its components. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
When assessing the potential of a contaminated site for bioremediation, it is desirable to know how much of the contaminant(s) is available for microbial degradation, thus allowing the likelihood of successful bioremediation to be predicted. The aims of this study were to investigate the degradation of PAHs in two soils by a catabolic inoculum and indigenous soil microflora and link this to the cyclodextrin extractable fraction in the presence of transformer oil (0.05, 0.01, or 0.005%). This study showed very little difference between indigenous and inoculum-derived degradation for phenanthrene in laboratory-aged soil, and strong relationships were also observed between both of the microbial degradative conditions and the amount of phenanthrene extracted by cyclodextrin. Furthermore, the indigenous degradation of PAHs in a field-contaminated soil showed significant linear correlations with the cyclodextrin extractable fraction, with gradients approximating to 1. There are several novel facets to this study. First, in aged, contaminated soils, indigenous microflora gave an equally sensitive determination of degradative availability as that measured by the catabolic inoculum. Second, this is the first time intrinsic biodegradation of PAHs has been predicted by the cyclodextrin extraction in laboratory-spiked and field-contaminated soils. The cyclodextrin extraction technique represents a powerful tool for predicting the extent of intrinsic and augmented microbial degradation and will be useful in the assessment of contaminated land prior to bioremediation. 相似文献
8.
Blakesley Richard E.; Mazumdar Sati; Dew Mary Amanda; Houck Patricia R.; Tang Gong; Reynolds Charles F. III; Butters Meryl A. 《Canadian Metallurgical Quarterly》2009,23(2):255
Hypothesis testing with multiple outcomes requires adjustments to control Type I error inflation, which reduces power to detect significant differences. Maintaining the prechosen Type I error level is challenging when outcomes are correlated. This problem concerns many research areas, including neuropsychological research in which multiple, interrelated assessment measures are common. Standard p value adjustment methods include Bonferroni-, Sidak-, and resampling-class methods. In this report, the authors aimed to develop a multiple hypothesis testing strategy to maximize power while controlling Type I error. The authors conducted a sensitivity analysis, using a neuropsychological dataset, to offer a relative comparison of the methods and a simulation study to compare the robustness of the methods with respect to varying patterns and magnitudes of correlation between outcomes. The results lead them to recommend the Hochberg and Hommel methods (step-up modifications of the Bonferroni method) for mildly correlated outcomes and the step-down minP method (a resampling-based method) for highly correlated outcomes. The authors note caveats regarding the implementation of these methods using available software. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
A ballistic deposition model, SIMBAD, has been extended to simulate physical vapor deposition onto substrates at elevated temperatures. The model has been expanded to account for the effect of film curvature on surface diffusion. The effects on via coverage and filling have been simulated for aluminum films, and complete planarization of a 1:1 aspect ratio via is predicted for a temperature of 550°C. Via aspect ratio and sidewall taper can also strongly affect coverage and filling. Biased sputtering has also been incorporated into the model and shows that a primary effect is a substantial reduction in the temperature required to achieve full planarization. However, void formation and substrate damage are problems predicted to occur under some bias sputter conditions 相似文献
10.
A study with 85 spinal-cord-injured male inpatients (mean age at time of injury 33.2 yrs; mean time since injury 10 yrs) evaluated the relative contributions of physical vs psychological variables to Ss' long-term perceptions of themselves after injury and illustrated the usefulness of a multivariate analytic approach to research questions about these effects. LISREL examinations of predictors (e.g., education, physical activities) and outcomes were conducted. Although some variables (e.g., level of injury) have long been assumed to exert powerful effects on all areas of adjustment to injury, causal analyses in the present study indicated that Ss' long-term perceptions of physical/externally observed features were best predicted by the same sort of predictor; a similar correspondence was seen for psychological/internally observed perceptions and their predictors. For example, level of injury was a relatively strong predictor of Ss' perceptions of health and physical activity, while perceptions of pain, which are acknowledged to have a large psychological component, were best predicted by more psychological predictors (e.g., S's role in sustaining the injury, S's level of education). The present authors assert that their assessment of the location and degree of correspondence between predictors and outcomes along a physical-psychological dimension of experience in the present study would not have been possible without causal analysis. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献