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1.
In order to formulate mathematical conjectures likely to be true, a number of base cases must be determined. However, many combinatorial problems are NP-hard and the computational complexity makes this research approach difficult using a standard brute force approach on a typical computer. One sample problem explored is that of finding a minimum identifying code. To work around the computational issues, a variety of methods are explored and consist of a parallel computing approach using MATLAB, an adiabatic quantum optimization approach using a D-Wave quantum annealing processor, and lastly using satisfiability modulo theory (SMT) and corresponding SMT solvers. Each of these methods requires the problem to be formulated in a unique manner. In this paper, we address the challenges of computing solutions to this NP-hard problem with respect to each of these methods.  相似文献   
2.
Although rapid smoking has proved to be a successful treatment strategy for smokers, its hazard potential has been recently debated. In the present study, 6 Ss (mean age 30.8 yrs) were monitored throughout 8 standard sessions of rapid smoking. Heart rate, blood pressure, and carboxyhemoglobin increases were generally higher than those reported in the few extant physiological studies of rapid smoking, and EKG abnormalities occurred in several Ss during rapid smoking. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
Design of a space channel simulator using virtual instrumentation software   总被引:2,自引:0,他引:2  
The ability to simulate satellite channels gives protocol designers the ability to test design options prior to their use in space communications. Here, we describe a software-based space channel simulator with variable channel error-rate, channel delay, and user bit error rate. This simulator is used to model the communications channel for testing various Internet-type protocol options for space communications.  相似文献   
4.
Despite the association of increasing age with chronic wound-healing disorders and an impaired rate of healing of acute cutaneous wounds, the role of matrix metalloproteinases (MMPs) is unknown. To determine the spatial and temporal patterns and activities of MMP-1, -2, -3 and -9, 132 healthy humans aged between 19 and 96 years underwent 4-mm punch biopsies followed by wound excision between day 1 and day 180 post-wounding. Wounds showed an age-related increase in MMP-2 and MMP-9 immunostaining from day 3; this was associated with degradation of gelatin as shown by zymograms and with increased proteinase activity as shown by azocoll assays. Distinct spatial localisations for each MMP were observed: MMP-2 was found in epidermal structures; MMP-9 was observed in inflammatory cells up to day 21; MMP-1 was localised to keratinocytes at the wound margin. Normal old skin showed pro-MMP-2 bands on zymography and increased MMP-2 immunostaining. These results indicate that: (1) intrinsic ageing is associated with the up-regulation of MMPs previously associated with chronic wound healing; (2) wound-tissue proteinases are essentially active up to day 21 postwounding; and (3) intrinsic ageing may predispose to tissue breakdown disorders because of MMP-2 up-regulation in normal skin.  相似文献   
5.
Cognitive, behavioral, and combined assertiveness treatments for dysfunctional job-interviewing skills were evaluated in a design that included high-demand and waiting list control treatments as well. Cognitive, behavioral, generalization, and control measures were used to determine the construct validity of hypothesized improvements. The cognitive treatment had no impact on any outcome variable. Some evidence to favor the behavioral treatment appeared on the cognitive assessment battery. However, given the failure of the behavioral treatment to register parallel changes on the behavioral battery, these cognitive improvements are not clearly attributable to behavioral theory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
Energy production from a coblended mixture of biosolids and food waste was optimised for hydrogen and methane production. Four different blends were prepared by varying the carbohydrate : protein (carb : pro) ratios. The biosolids contained a low carbohydrate fraction and so was not suitable for hydrogen production when used alone. However coblending this waste with a carbohydrate‐enriched food waste produced a greater hydrogen yield, making this option viable. Batch studies showed that the optimised mix had a biosolids concentration of 25.7% (w/w). The largest hydrogen yield of 198.5 mL/gVSremoved was observed when the carb : pro was 2.78, and this was threefold higher than the other carb : pro ratios evaluated in this study. The digestate recovered after hydrogen recovery had a C : N of 17.5, which is in the ideal range for methane production. The biochemical methane potential test showed a methane yield of 239 mL/gVSremoved, and the total volatile solids destruction following two‐phase hydrogen and methane production was 93%.  相似文献   
7.
A social marketing approach used both qualitative and quantitative methods to develop a hygiene behaviour intervention in rural north-east Thailand. Behaviours were preselected from a previous study and the intervention was designed to promote hand washing, especially before feeding a baby, cooking, eating, and after defaecation or cleaning a baby's bottom, and dish washing immediately after eating. A bacteriological indicator (enumerating faecal streptococci using a finger impression technique) was developed to measure changes in hand washing behaviour and observation (spot checks) of dirty dishes to indicate dish washing practice. There was a significant improvement in both behaviours and a significant reduction in diarrhoeal disease as a result of the intervention. Furthermore, both indicators were retrospectively found to be positively related to diarrhoeal disease incidence. However, receiving and being able to recall the intervention messages was not necessarily sufficient to ensure behaviour change, as some adults found it difficult to change old habits. Villages showing the greatest improvement tended to have a stronger sense of community than others and to have more people actively involved in the intervention.  相似文献   
8.
60 male and female 24–50 yr old recovering alcoholic counseling clients were assigned randomly to 1 of 3 male counselors and to 1 of 2 treatment conditions. In the nonstandard English condition, the counselor casually and passively introduced 4 profane words. The standard English condition was identical except in respect to the use of these specific words. On client self-report and behavioral measures, which cut across all schools of counseling, counselors who used nonstandard English were judged to be less effective and satisfying. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
The stress inoculation (SI) paradigm, which consists of education (ED), coping skills training (CST), and exposure to simulated stressors (EX), was applied to the occupational stress experienced by nurses. Occupational stress was operationally defined in terms of 13 dependent measures reflecting problem areas summarized by the acronym ReACT (retrograde complaints, assertiveness deficits, competency concerns, and time stress). ReACT also stood for the ingredients of the CST component (relaxation training, assertive skill building, cognitive restructuring, and time management instruction). To determine which SI components produce a treatment effect, 60 White female acute-care registered nurses (mean age 33.8 yrs) were randomly assigned to 1 of 4 active treatment cells: SI, CST, EX, ED, or no treatment (NT). Ss were administered a battery of tests that included the State–Trait Anxiety Inventory and Rathus Assertiveness Schedule. A MANOVA at posttest, and subsequent univariate analyses simultaneously considering 4-mo follow-up data, demonstrated that SI is an effective treatment with durable benefits and that CST is its principal ingredient. Additional demand-characteristics analyses indicated that these effects are not due to placebo-related phenomena. (54 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
A highly potent inhibitor of calmodulin-sensitive phosphodiesterase (PDE) activity was isolated from the culture broth of an unidentified fungal isolate, SCF-125. A chemically defined medium was developed for production of this compound. The PDE inhibitor was isolated from the fermentation filtrate by adsorption on a macro-reticular resin and further purified by gel filtration chromatography and reverse-phase HPLC. The major PDE inhibitor was identified as cephalochromin, a bis-naphthopyrone, by spectral data analysis. The compound, SCH 45752, inhibited calmodulin-sensitive PDE activities with IC50 values of 40-47 nM. It inhibited the activities of calmodulin-independent PDE and various protein kinases with higher IC50 values (2-40 microM). SCH 45752 does not appear to be a calmodulin antagonist. Furthermore, SCH 45752 affects smooth muscle contraction at a concentration of 30 microM; it potentiated the relaxing effect of sodium nitroprusside on carotid artery media contracted by histamine. Thus SCH 45752 is one of the most potent inhibitors of calmodulin-sensitive PDE activity known, and it is capable of exerting a pharmacological effect in at least one intact tissue model.  相似文献   
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