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71.
OBJECTIVE: It is commonly believed that the full moon exerts an influence on violence and aggression in psychiatric settings. The literature to date is contentious. This study used a robust methodology to examine the hypothesis that there was an increased frequency of violent and aggressive behaviour among hospitalised psychiatric clients at the time of the full moon. METHOD: Prospective data were collected in five inpatient psychiatric settings across the Northern Sydney Area Health Service. Morrison's hierarchy of violence and aggression was used to rate behaviour. Lunar phases were clearly defined and Poisson regression used to examine relationships between lunar phase and violence. Extraneous temporal variation was considered. RESULTS: No significant relationship was found between total violence and aggression or level of violence and aggression and any phase of the moon. CONCLUSION: Future research could profitably examine the implications of a belief in the lunar effect among health workers in the face of evidence that no relationship exists between violence, aggression and the lunar cycle. 相似文献
72.
73.
This article presents the HIST approach, which allows the automated insertion of self test hardware into hierarchically designed circuits and systems to implement the RUNBIST instruction of the IEEE 1149.1 standard. To achieve an optimal and throughout self testable system, the inherent design hierarchy is fully exploited. All chips and boards are provided with appropriate test controllers at each hierarchy level. The approach is able to detect all those faults, which are in the scope of the underlying self test algorithms. In this paper the hierarchical test architecture, the test controllers as well as all necessary synthesis procedures are presented. Finally a successful application of the HIST approach to a cryptography processor is described. 相似文献
74.
A diode pumped, commercially packaged, thulium doped fluoride fiber amplifier (TDFFA) operating in the region of 0.8 μm has been characterized. The unit is capable of producing large small signal gains, low noise figures and high saturated output powers. A power amplifier slope efficiency of 62% has been achieved at 810 nm. The same TDFFA unit was used in a series of systems experiments, at data rates of 310 Mb/s and 1.2 Gb/s, in the first telecommunications window. The results of this work indicate that data can be transmitted over ≈10 km lengths of both singlemode and standard transmission fiber, while still allowing significant margin to split the signal to a number of customers. The application of the TDFFA could therefore have significant benefit for future LAN/MAN type systems architectures involving large signal splits to customer's premises 相似文献
75.
Part 1 concerns representation: Pop-out for a target that can be distinguished from the distractors only by the relative position of its components was demonstrated, thereby showing that simple shape information is represented preattentively. Findings are discussed in terms of early- vs late-selection debate and in terms of theories of search and texture segregation. Part 2 concerns selection: Strong learning in a varied-mapping paradigm was demonstrated, and it was shown that preattentive shape information can be used for selection. Finally, an account of the learning, namely the group scale hypothesis, is suggested and a final experiment to test it is presented. Results confirm and extend the emphasis placed by J. Duncan and G. W. Humphreys's (1989) attentional engagement theory on grouping processes in visual search. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
Montmorillinite clays, modified with either Zn(II) or Fe(III) chlorides have been used to catalyze the Friedel-Crafts alkylation of thiophene. High yields (ca. 80%) of 2- and 3-benzylthiophene mixtures were obtained using either catalyst in chlorobenzene or nitrobenzene solvent at 80°C. The ratio of 2–3-products was found to be controlled by their relative stability. Reactions were most rapid in nitrobenzene solution (<5 min) and resulted in formation of the 2-isomer as the only mono-substituted product. This is believed to be the first example in which an alkylation of thiophene has been limited to one regio-isomer. 相似文献
77.
Steven S Fu Miles McFall Andrew J Saxon Jean C Beckham Timothy P Carmody Dewleen G Baker Anne M Joseph 《Nicotine & tobacco research》2007,9(11):1071-1084
We conducted a systematic review of what is known about the relationship between post-traumatic stress disorder (PTSD) and smoking to guide research on underlying mechanisms and to facilitate the development of evidence-based tobacco treatments for this population of smokers. We searched Medline, PsychINFO, and the Cochrane Central Register of Controlled Trials and identified 45 studies for review that presented primary data on PTSD and smoking. Smoking rates were high among clinical samples with PTSD (40%-86%) as well as nonclinical populations with PTSD (34%-61%). Most studies showed a positive relationship between PTSD and smoking and nicotine dependence, with odds ratios ranging between 2.04 and 4.52. Findings also suggest that PTSD, rather than trauma exposure itself, is more influential for increasing risk of smoking. A small but growing literature has examined psychological factors related to smoking initiation and maintenance and the overlapping neurobiology of PTSD and nicotine dependence. Observational studies indicate that smokers with PTSD have lower quit rates than do smokers without PTSD. Yet a few tobacco cessation treatment trials in smokers with PTSD have achieved quit rates comparable with controlled trials of smokers without mental disorders. In conclusion, the evidence points to a causal relationship between PTSD and smoking that may be bidirectional. Specific PTSD symptoms may contribute to smoking and disrupt cessation attempts. Intervention studies that test behavioral and pharmacological interventions designed specifically for use in patients with PTSD are needed to reduce morbidity and mortality in this population. 相似文献
78.
The protein translocation ATPase of Escherichia coli, SecA protein, auto-regulates its translation by binding to its translation initiation region in geneX-secA mRNA. To analyze this regulation further the secondary structure of this portion of geneX-secA RNA was investigated utilizing structure-specific nucleases and chemical probing approaches. The results of this analysis were consistent with the existence of two adjacent helices, helix I and the lower portion of helix II, whose function in secA activation and repression, respectively, has been demonstrated. Binding of SecA protein to geneX-secA RNA or various mutant derivatives of this RNA was studied by measurement of affinity constants, RNA footprint analysis, and quantitation of auto-repression in vivo. This analysis showed that the SecA-binding site in geneX-secA RNA was remarkably large spanning a region of 96 nucleotides including a 3' portion of helix II, the secA translation initiation region and distal sequences. From the size of the SecA-binding site and the plasticity of its response to mutational alteration, it is suggested that SecA protein contains two distinct RNA-binding sites. Finally, it was shown that SecA binding was not sufficient to promote auto-regulation and that sequences both upstream (helix I) and within the binding site can contribute to auto-regulation without affecting SecA-binding affinity. 相似文献
79.
Marie L. Borum Kathleen L. Shehan Hans Fromm Saleem Jahangeer Marianne K. Floor Oliver Alabaster 《Lipids》1992,27(12):999-1004
The effect and possible interactive influence of different dietary amounts of wheat bran, fat and calcium on the fecal excretion,
concentration and composition of bile acids was studied in Fischer-344 rats. The fecal bile acids were analyzed using gas-liquid
chromatography. Dietary wheat bran increased both total bile acid excretion and fecal weight without changes in fecal bile
acid concentration. The proportion of fecal hyodeoxycholic acid decreased with increasing dietary fiber, whereas that of lithocholic
and deoxycholic acids increased significantly with fiber intake. The percent content of fecal chenodeoxycholic acid did not
change. Increasing dietary fat led to an increase in bile acid excretion without changes in either fecal weight or bile acid
concentration. In contrast, the level of dietary calcium did not affect the total excretion of bile acids. However, since
calcium increased the fecal weight, it consequently diluted bile acids and decreased their fecal concentration. Dietary fat
and calcium had no influence on fecal bile acid composition. There were no interactive effects of wheat bran, fat and calcium
on fecal bile acids. The finding in this study that dietary fiber, fat and calcium induce significant changes in fecal bile
acids may be of relevance to the potential of bile acids to promote carcinogenesis. 相似文献
80.