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101.
Much has been said recently concerning the Moche culture of Peru (100 to 700 ) which preceded the more widely known Inca society. Since there was no written language, what is known about the Moche people has been through the artifacts produced, their design and craftsmanship. This study concerns the PIXE analysis of the matrix and the red and white surface patterns of six stirrup handled earthenware vessels. The results suggest different techniques were applied for producing the coloring and surface designs and that a common source of clays was not used in the construction.  相似文献   
102.
Pseudomonas putida MnB1 is an isolate from an Mn oxide-encrusted pipeline that can oxidize Mn(II) to Mn oxides. We used transposon mutagenesis to construct mutants of strain MnB1 that are unable to oxidize manganese, and we characterized some of these mutants. The mutants were divided into three groups: mutants defective in the biogenesis of c-type cytochromes, mutants defective in genes that encode key enzymes of the tricarboxylic acid cycle, and mutants defective in the biosynthesis of tryptophan. The mutants in the first two groups were cytochrome c oxidase negative and did not contain c-type cytochromes. Mn(II) oxidation capability could be recovered in a c-type cytochrome biogenesis-defective mutant by complementation of the mutation.  相似文献   
103.
OBJECTIVE: Primary generalized osteoarthritis (OA), the most prevalent joint disease, is usually symmetric. Sporadic case reports mention decreased OA manifestations in limbs in which there are neurologic deficits, but no systematic research has been published. The aim of the present study was to examine these observations in a planned and controlled survey in a group of patients with OA. METHODS: Seventy-five geriatric patients with a history of stroke and hemiparalysis were studied clinically and radiographically (hand radiographs; graded according to a modified Altman method) for the presence and the degree of OA in the hands. Detailed clinical and radiologic scores were calculated for each hand. Demographic, occupational, and neurologic data were collected. Patients with other joint or neurologic conditions were excluded. A group of 55 elderly patients without stroke were similarly studied (controls). Scores in the paralyzed hand were compared with those in the nonparalyzed hand in the stroke patients and subgroups (by Student's paired t-test and Wilcoxon test). Scores in the dominant hands were compared with those in the nondominant hands in stroke patients and control subjects (by Student's paired t-test and Mann-Whitney test). Correlation between the degree of neurologic damage and OA asymmetry (Pearson's correlation coefficient) was also sought. RESULTS: Paralyzed hands showed significantly fewer OA changes than nonparalyzed hands, both clinically and radiologically. This trend, accentuated in patients with more severe paralysis, disappeared in those with mild residual paresis. Asymmetry of OA was more pronounced in patients with flaccid, compared with spastic, paralysis. The degree of paralysis and loss of muscle strength correlated with the degree of OA asymmetry. Women had significantly higher OA scores than men. In the control group, dominant hands had higher OA scores, but this finding was concealed among hemiparalyzed patients. Lifetime gross occupational load and present grip strength did not correlate with the degree of OA. CONCLUSION: In elderly patients, hemiparalysis reduces ipsilateral hand expression of OA, while OA is accentuated (or increased) in the dominant hand of patients without paralysis. This first systematic study confirms the findings of previous case reports and lends support to the role of biomechanical factors in the development of OA.  相似文献   
104.
Prospective measures of risk factors for partner abuse were obtained from a large birth cohort in 4 domains: socioeconomic resources, family relations, educational achievements, and problem behaviors. Partner abuse outcomes were measured at age 21. Results showed that antecedents of abuse included risk factors from all 4 domains. Risk factors were similar for men and women. Some age 3 antecedents were significant, but the strongest correlations were from age 15. In multivariate analyses, the most consistent predictor was the presence of early problem behaviors. In a cross-validation test, abuse was moderately predictable by the same antecedents, whether the outcome measure was self-report or reports from partners of sample members. Findings suggest that theories of partner abuse should account for developmental influences from multiple life domains and that primary prevention of partner abuse should begin in adolescence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
105.
This study tested whether partners can be relied on to provide congruent reports about abuse in their relationship. The authors examined whether interpartner agreement (IA) varies as a function of whether the perpetrator is the man or the woman, and by whether the abusive behavior being reported is physical or psychological. Guided by psychometric test theory, the authors examined whether weak IA about specific behaviors can be improved by aggregating behavior items into scales and by controlling for random measurement error. A representative sample of 360 young couples was studied. IA did not vary with the perpetrator's gender or with the nature of the abusive behaviors, but victims (both men and women) reported somewhat more abuse than did their perpetrators. IA about specific abusive behaviors was only poor to fair, but it became very good when items were aggregated into scales and even better when measurement errors were removed form the reports. The findings suggest that reports of abuse can be aggregated to form internally consistent scales that show strong IA, thereby fulfilling criteria for reliability. Moreover, under research conditions that guarantee confidentiality, either abuser reports or victim reports are suitable methods for use in research on partner abuse. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
106.
Examined processes linking biological and behavioral changes in different contexts during adolescence by studying an unselected cohort of New Zealand girls from childhood through adolescence when they entered either mixed-sex or all-girl secondary schools. The impact of menarcheal timing on female delinquency was moderated by the sex composition of schools; early-maturing girls in mixed-sex settings were at greatest risk for delinquency. Individual differences in delinquency were also significantly more stable among girls in mixed-sex schools than among those in all-girl schools. These contextual variations are interpreted in terms of the differential distribution of reinforcements and opportunities for delinquency. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
107.
A preliminary examination of some potential safety questions for conceptual fusion-fission hybrid reactors is presented in this paper. The study and subsequent analysis was largely based upon one design, a conceptual mirror fusion-fission reactor, operating on the deuterium-tritium plasma fusion fuel cycle and the uranium-plutonium fission fuel cycle. The major potential hazards were found to be: (a) fission products, (b) actinide elements, (c) induced radioactivity, and (d) tritium.As a result of these studies, it appears that highly reliable and even redundant decay heat removal must be provided. Loss of the ability to remove decay heat results in melting of fuel, with ultimate release of fission products and actinides to the containment. In addition, the studies indicate that blankets can be designed which will remain subcritical under extensive changes in both composition and geometry. Magnet safety and the effects of magnetic fields on thermal parameters were also considered.  相似文献   
108.
In Mott materials strong electron correlation yields a spectrum of complex electronic structures. Recent synthesis advancements open realistic opportunities for harnessing Mott physics to design transformative devices. However, a major bottleneck in realizing such devices remains the lack of control over the electron correlation strength. This stems from the complexity of the electronic structure, which often veils the basic mechanisms underlying the correlation strength. This study presents control of the correlation strength by tuning the degree of orbital overlap using picometer-scale lattice engineering. This study illustrates how bandwidth control and concurrent symmetry breaking can govern the electronic structure of a correlated SrVO3 model system. This study shows how tensile and compressive biaxial strain oppositely affect the SrVO3 in-plane and out-of-plane orbital occupancy, resulting in the partial alleviation of the orbital degeneracy. The spectral weight redistribution under strain is derived and explained, which illustrates how high tensile strain drives the system toward a Mott insulating state. Implementation of such concepts can push correlated electron phenomena closer toward new solid-state devices and circuits. These findings therefore pave the way for understanding and controlling electron correlation in a broad range of functional materials, driving this powerful resource for novel electronics closer toward practical realization.  相似文献   
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