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1.

Background  

Bioelectrical Impedance (BIA) derived phase angle is increasingly being used as an objective indicator of nutritional status in advanced cancer. Subjective Global Assessment (SGA) is a subjective method of nutritional status. The objective of this study was to investigate the association between BIA derived phase angle and SGA in advanced colorectal cancer.  相似文献   
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New standards for drinking water disinfection require better optimization of the ozonation stage on the basis of the concentration×contact time (CT) concept, and production of ozone from pure oxygen at higher concentrations presumes application of the new type of contactors operating efficiently at lower gas/liquid volumetric ratios. One possible construction to meet these requirements is a downstream static mixer with sieve plates. At higher flow rates of liquid in this mixer, the interfacial area may reach 10,000m2/m3 at energy dissipation 1–5kW/m3. Due to the very intensive hydrodynamic regime the ozone utilization degree in the gas phase reaches 98–100% in natural lake water ozonation. Mathematical simulation of lake water ozonation in this mixer indicated that the process proceeds mostly in the diffusion or kinetic regime depending on the operating parameters. The dominating parameters besides the sieve geometry are the liquid flow rate in the holes of the sieves and the volumetric liquid/gas ratio.  相似文献   
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64 children from Grades 2 and 5 participated in a recall task. There were 4 instructional conditions distinguished by the type of retrieval cue: sign, subcategory, supracategory, and control. The task required that the Ss image and recall items from 6 successively presented sets of categorized pictorial stimuli. These categories, however, were not mentioned; instead, a sign representing an activity for each set was emphasized as the retrieval cue. Significant effects of grade and of condition, favoring the subcategory condition, were determined by ANOVA. The results, based upon total recall as well as items-per-category and category recall, are discussed in relation to E. Tulving and M. J. Watkins's (see record 1975-26816-001) encoding specificity principle, A. Paivio's (1971) 2-process theory of memory, and F. I. Craik and R. S. Lockhart's (see record 1973-20189-001) levels-of-processing approach to memory. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The design and preparation of isotropic silver nanowire‐polystyrene composites is described, in which the nanowires have finite L/D (< 35) and narrow L/D distribution. These model composites allow the L/D dependence of the electrical percolation threshold, ?c, to be isolated for finite‐L/D particles. Experimental ?c values decrease with increasing L/D, as predicted qualitatively by analytical percolation models. However, quantitative agreement between experimental data and both soft‐core and core–shell analytical models is not achieved, because both models are strictly accurate only in the infinite‐L/D limit. To address this analytical limitation, a soft‐core simulation method to calculate ?c and network conductivity for cylinders with finite L/D are developed. Our simulated ?c results agree strongly with our experimental data, suggesting i) that the infinite‐aspect‐ratio assumption cannot safely be made for experimental networks of particles with L/D < 35 and ii) in predicting ?c, the soft‐core model makes a less significant assumption than the infinite‐L/D models do. The demonstrated capability of the simulations to predict ?c in the finite‐L/D regime will allow researchers to optimize the electrical properties of polymer nanocomposites of finite‐L/D particles.  相似文献   
6.
Label-free DNA detection plays a crucial role in developing point-of-care biochips. Capacitance detection is a promising technology for label-free detection. However, data published in literature often show evident time drift, large standard deviation, scattered data points, and poor reproducibility. To address these problems, mercapto-hexanol or similar alkanethiols are usually considered as blocking agents. The aim of the present paper is to investigate new blocking agents to further improve DNA probe surfaces. Data from AFM, SPR, florescence microscopy, and capacitance measurements are used to investigate new lipoate and ethylene-glycol molecules. The new surfaces offer further improvements in terms of diminished detection errors. Film structures are investigated at the nano-scale to justify the detection improvements in terms of probe surface quality. This study demonstrates the superiority of lipoate and ethylene-glycol molecules as blocking candidates when immobilizing molecular probes onto spot surfaces in label-free DNA biochip.  相似文献   
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A model of risk regulation is proposed to explain how low and high self-esteem people balance the tension between self-protection and connectedness goals in romantic relationships. This model assumes that interpersonal risk automatically activates connectedness and self-protection goals. The activation of these competing goals then triggers an executive control system that resolves this goal conflict. One correlational study and 8 experiments manipulating risk, goal strength, and executive strength and then measuring implicit and explicit goal activation and execution strongly supported the model. For people high in self-esteem, risk triggers a control system that directs them toward the situations of dependence within their relationship that can fulfill connectedness goals. For people low in self-esteem, however, the activation of connectedness goals triggers a control system that prioritizes self-protection goals and directs them away from situations where they need to trust or depend on their partner. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
The acute effects of flumazenil, a benzodiazepine (BZD) receptor antagonist in long-term BZD users were used as a possible test to detect physiological dependence. Thirty-four subjects (20 females, 14 males) aged 26-48 years (mean + SD, 42.4+/-8.5 years), all chronic users of low doses of diazepam (5-20 mg/day, 14.2+/-4.8 mg/day) for 5 to 28 years (10.5+/-6 years), received a single 1-mg i.v. flumazenil dose or saline, infused slowly under double-blind conditions. Physiological dependence was suggested as all patients receiving flumazenil developed an anxiety reaction while the placebo group did not. Flumazenil triggered a qualitatively different reaction amounting to a panic attack during infusion in nine out of 15 patients. These patients had a diagnosis of panic disorder or a history of panic attacks. Caution should be exercised when giving flumazenil to panic patients who are taking BZDs as maintenance treatment.  相似文献   
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