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教师是人类文化、科学知识的传播者,是人类开发理性、奔向光明的引路人.教师的地位举足轻重,提高教师的素质,重视师德修养,具有极其深远的意义.  相似文献   
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Given that the state was central to the Soviet Communism, the paths and practices of its transformation need to be carefully studied. This article probes the emerging dimensions of a new state-market-crime nexus. It explores processes leading to a substantial merger betweebn the transforming state and new, controlled markets, whereby both are shaped and suffused by state/corporate criminal organized interests. These processes confound the traditional dilemma of `too much' or `to little' state as the state and law are simultaneously undetermined and fortified, dwarfed and augmented, supplanted and made indispensable by the quasi marketization of corruption, crime, security and surveillance. This article serves as an introduction to the papers collected in the present volume.  相似文献   
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Estimation of age in individuals has received considerable attention in forensic science, in which it is a widely used method for individual identification, together with paleo-demographic analyses to establish mortality patterns in past populations. The present investigation, which is a continuation of a previously published pilot study, was conducted to examine the possible application of the pulp/tooth area ratio by peri-apical images as an indicator of age at death. A total of 200 peri-apical X-rays of upper and lower canines were assembled from 57 male and 43 female skeletons of Caucasian origin, aged between 20 and 79 years. They belong to the Frassetto osteological collection of Sassari (Sardinia) and are housed in the Museum of Anthropology, Department of Experimental and Evolutionistic Biology, University of Bologna. For each skeleton, dental maturity was evaluated by measuring the pulp/tooth area ratio on upper (x(1)) and lower (x(2)) canines. Very good agreement was found between intraobserver measurements. Statistical analysis was performed in order to obtain multiple regression formulae for dental age calculation, with chronological age as dependent variable, and gender, and upper and lower canines as independent variables. Stepwise regression analysis showed that gender did not contribute significantly to the fit (p=0.881) whereas variables x(1) and x(2) and the first-order interaction between them did. These two variables explained 92.5% of variations in estimated chronological age and the residual standard error was 4.06 years. Lastly, two simple linear regression equations were obtained for age estimation using canines from the maxilla and mandible separately. Both models explained 86% of variations in estimated chronological age and allowed an age-at-death estimate with a residual standard error of about 5.4 years.  相似文献   
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Autolysis and putrefaction are crucial factors responsible for degradation of cells, tissues, and organs. Postmortem changes may assume different course depending on extrinsic and intrinsic conditions. The aim of the study was assessment of environmental effect on typeability of AmpFlSTR SGM Plus loci: D3S1358, VWA, D16S539, D2S1338, D81179, D21S11, D18S51, D19S433, TH01, FGA, and gender marker amelogenin. Brain and thyroid gland tissue specimens collected during autopsies of five persons aged 20-30 years were incubated at 21 degrees C and 4 degrees C in different environmental conditions. DNA was extracted by organic method from tissue samples collected in 7-day intervals and subsequently typed using AmpFlSTR SGM Plus kit and ABI 310. A fast decrease in typeability rate was seen in specimens incubated in peat soil and in sand. Brain tissue samples were typeable in all AmpFlSTR SGM Plus loci within 126 days of incubation at 4 degrees C. Faster DNA degradation was recorded in thyroid gland specimens. In samples with negative genotyping results, no DNA was found by fluorometric quantitiation.  相似文献   
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Changes in the size of the pulp canal, caused by apposition of secondary dentine, are the best morphometric parameters for estimating age by X-rays. The apposition of secondary dentine is the most frequently used method for age estimation in adult subjects. In two previous papers, we studied the application of the pulp/tooth area ratio by peri-apical X-rays as an indicator of age at death. The aim of the present study was to test the accuracy of age evaluation by combined analysis of labio-lingual and mesial peri-apical X-rays of lower and upper canines. A total of 200 such X-rays were assembled from 57 male and 43 female skeletons of Caucasian origin, aged between 20 and 79 years. For each skeleton, dental maturity was evaluated by measuring the pulp/tooth area ratio according to labio-lingual and mesial X-rays on upper (x(1), x(2)) and lower (x(3), x(4)) canines. Very good agreement was found between intra-observer measurements. Statistical analysis showed that all variables x(1), x(2), x(3), and x(4) and the first-order interaction between x(1) and x(3) contributed significantly to the fit, so that they were included in the regression model, yielding the following regression formula: Age = 120.737 - 337.112x(1) - 79.709x(2) - 364.534x(3) - 65.655x(4) + 1531.918x(1)x(3) . The residual standard error of estimated ages was 3.62 years, with 94 degrees of freedom, and the median of the residuals was -0.155 years, with an interquartile range of 4.96 years. The accuracy of the method was ME = 2.8 years, where ME is the mean prediction error. The model also explained 94% of total variance (R(2) = 0.94).  相似文献   
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Allele frequencies for the 15 tetranucleotide short tandem repeat loci contained in the AmpFlSTR Identifiler kit were obtained from a population sample of 219 unrelated individuals born in the western part of Romania.  相似文献   
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This paper focuses on the importance of family member closeness as a protective factor against domestic abuse. We explore the link between long-lasting relations within the family and intra-familial violence perpetrated against women in Latino households in South Florida. We use data from an Inter-generational Transmission of Drug Use between Latina Mothers and Daughters (ITDMD) study. The study includes data on family relations and domestic abuse. We estimate a series of multivariate regressions to obtain the probability of abuse against women, the types of abuse inflicted and the relationship with the abusers. Our results indicate that among abused women, the effects of long-lasting relations within the family differ depending on the type of relationship between the abuser and the victim and the degree of closeness the victim feels towards other family members. Given these findings, there is a need to further study family relations and abuse in Latino households.  相似文献   
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