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831.
网络环境下如何构筑版权保护体系是网络时代迫切需要解决的问题 ,文章认为应当从法律实现和社会实现两个角度来实现对版权保护 ,并提出了一些具体的想法。  相似文献   
832.
网络营销重塑营销理念   总被引:2,自引:0,他引:2  
本文通过对网络营销与传统营销的比较,分析了信息时代网络营销对传统经营方式的冲击,探讨了网络营销给人们带来的全新观念变化。  相似文献   
833.
为表达传染性喉气管炎病毒(ILTV)gD蛋白,根据GenBank中登录的ILTV全基因组序列(EU675324)设计了1对引物,进行gD全基因的PCR扩增,产物经纯化后连接至pGEM-T Easy载体,进行序列测定,采用DNAStar软件分析gD蛋白的抗原性,选择抗原性强的第256~405aa的编码片段设计引物并进行PCR扩增,结果获得截短的gD基因,将其克隆至原核表达载体pET-32a中,并转化E.coli BL21(DE3)。经IPTG诱导后,获得大小为43.5ku的重组蛋白,命名为r-gD。Western-blot分析结果表明,r-gD具有较强的抗原性。  相似文献   
834.
Many respondents to opinion surveys say that the citizen's race influences how police officers treat the public, yet recent expert social‐science panels have declared that research findings are too contradictory to form a conclusion on whether American police are biased against racial minorities. We perform a meta‐analysis of quantitative research that estimates the effect of race on the police decision to arrest. Screening nearly 4,500 potential sources, we analyze the results based on 27 independent data sets that generated 40 research reports (both published and unpublished) that permitted an estimate of the effect size of the suspect's race on the probability of arrest. The meta‐analysis shows with strong consistency that minority suspects are more likely to be arrested than White suspects. Depending on the method of estimation, the effect size of race varied between 1.32 and 1.52. Converting the race effect size to probabilities shows that compared with the average probability in these studies of a White being arrested (.20), the average probability for a non‐White was calculated at .26. The significant race effect persists when taking into account the studies’ variations in research methods and the nature of explanatory models used in the studies. Implications for future research are presented.  相似文献   
835.
Abstract: Thin layer chromatography (TLC) is a technique that is commonly employed in the forensic drug analysis of pharmaceutical preparations. Detection is typically accomplished using various visualization spray reagents. Conventional gas chromatography–mass spectrometry (GC‐MS) analysis is typically performed to confirm the TLC results. Depending on the drugs tested and the instrument conditions required, this confirmation can take up to an hour to complete. Direct analysis in real time (DART?) is an ionization source, coupled to an accurate‐mass time‐of‐flight mass spectrometer that has the capability to ionize materials under ambient conditions. To streamline analysis, the combination of TLC with DART? detection is proposed to screen and subsequently identify drug compounds, all from the same TLC plate. DART? confirmations of TLC analyses take <10 min to complete and compare favorably to GC‐MS in sensitivity and selectivity. This study validates the use of TLC‐DART in the forensic identification of the components of several pharmaceutical preparations.  相似文献   
836.
FRANK M. WEERMAN 《犯罪学》2011,49(1):253-286
In this article, longitudinal social network data are analyzed to get a better understanding of the interplay between delinquent peers and delinquent behavior. These data contain detailed information about the social networks of secondary school students from the same grade, their delinquent behavior, and many relevant correlates of network formation and delinquency. To distinguish selection and influence processes, a method (Simulation Investigation for Empirical Network Analyses, SIENA) is used in which network formation and changes in delinquency are simulated simultaneously within the context of other network processes and correlates of delinquency. The data and the method used make it possible to investigate an unusually wide array of effects on peer selection and delinquent behavior. The results indicate that similarity in delinquency has no significant effect on the selection of school friends when other network dynamics are taken into account. However, the average delinquency level of someone's friends in the school network does have a significant, although relatively small, effect on delinquent behavior of the respondents, beyond significant effects of changes in the level of self‐control and morality. Another peer‐related change, leaving or joining informal street‐oriented youth groups, also appears to have a substantial effect on changes in delinquency.  相似文献   
837.
Abstract: DNA mixtures with two or more contributors are a prevalent form of biological evidence. Mixture interpretation is complicated by the possibility of different genotype combinations that can explain the short tandem repeat (STR) data. Current human review simplifies this interpretation by applying thresholds to qualitatively treat STR data peaks as all‐or‐none events and assigning allele pairs equal likelihood. Computer review, however, can work instead with all the quantitative data to preserve more identification information. The present study examined the extent to which quantitative computer interpretation could elicit more identification information than human review from the same adjudicated two‐person mixture data. The base 10 logarithm of a DNA match statistic is a standard information measure that permits such a comparison. On eight mixtures having two unknown contributors, we found that quantitative computer interpretation gave an average information increase of 6.24 log units (min = 2.32, max = 10.49) over qualitative human review. On eight other mixtures with a known victim reference and one unknown contributor, quantitative interpretation averaged a 4.67 log factor increase (min = 1.00, max = 11.31) over qualitative review. This study provides a general treatment of DNA interpretation methods (including mixtures) that encompasses both quantitative and qualitative review. Validation methods are introduced that can assess the efficacy and reproducibility of any DNA interpretation method. An in‐depth case example highlights 10 reasons (at 10 different loci) why quantitative probability modeling preserves more identification information than qualitative threshold methods. The results validate TrueAllele® DNA mixture interpretation and establish a significant information improvement over human review.  相似文献   
838.
The high prevalence of alprazolam abuse translates to an increased workload for crime laboratories in characterizing seized tablets. These tablets may originate as diverted pharmaceuticals or counterfeited mimics, so efficient analytical techniques should provide confirmatory data while minimizing destruction of evidence. We offer the first report of a validated forensic method for confirming alprazolam tablets by direct analysis in real time-time of flight (DART-TOF) mass spectrometric analysis. This technique provides rapid identification of target analytes with minimal sample preparation, allowing direct analysis in the atmospheric sample gap. Selectivity is achieved through high resolution and mass accuracy, unique ion fragments, and chlorine isotopic ratios. This method utilizes fragmentation in two separate voltage functions to observe the alprazolam pseudo molecular ion at 309.09070 using 40 V and major ion fragments of 281.07197 and 205.07657 at 120 V. These parameters allow our laboratory to confirm alprazolam tablets efficiently, without compromising quality forensic standards.  相似文献   
839.
This study investigates whether a writer's gender can be determined from an inspection of simulated signatures written in the Arabic alphabet or Arabic abjad. It is generally believed that the penmanship of female writers is superior to male writers. There is also reason to expect that superiority in writing skill might contribute to success in simulating the signatures of other writers. Simulated signatures produced by a large population of male (414) and female (312) Arabic writers were graded, and the results were statistically analyzed. Women were found to have a marginal advantage simulating all elements of the signatures, but there was no statistically significant difference between the genders on any of the elements examined.  相似文献   
840.
以南京市城乡若干社区的实证调查为研究个案,深入探讨居民对街道办(乡镇)政府的信任度对居民参与社区志愿服务的意愿与居民的社区志愿精神究竟有何种程度的影响。通过Logistic回归分析,研究结果发现居民对街道办(乡镇)政府的信任度与居民的社区志愿精神之间存在着密切的关联性。对于各级政府而言,本研究的政策含义是需要特别关注影响居民对街道办(乡镇)政府信任的各种居民背景因素,培育居民对街道办(乡镇)政府的信任感和亲切感,不断促进居民社区志愿精神的孕育与成长,从而凝聚成社区草根民主成长的动力和纽带。  相似文献   
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