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81.
20世纪末以来中、美与东盟的三边互动关系——以权力转移为视角 总被引:1,自引:0,他引:1
中国的崛起对美国和东盟均产生重大影响,导致中、美和东盟在经贸、政治和认知方面形成了互动关系。由于经济领域的区域经济一体化、贸易转移效应和政治领域东亚一体化的排斥效应等因素,中美在东亚的权力关系发生了转移,东亚秩序经历了结构性调整。三方在经贸、政治和认知的互动相互影响并呈正相关关系,使得东亚的权力转移在和平中实现。互动中仍存在一些问题需要三方调适和合作加以解决。 相似文献
82.
从中苏到中俄,从同盟、对抗到伙伴,这三种关系模式如同历史本身的有机发展一样,彼此之间有着深厚的逻辑关联。一方面,同盟和对抗模式为伙伴模式提供了极为丰厚的历史遗产,对其产生了不可割舍的内在影响和制约。另一方面,伙伴模式在20世纪90年代后之所以能够得到全面、持续而又深入地构建,是与其对同盟和对抗模式所进行的辩证继承和扬弃分不开的。 相似文献
83.
K. A. Thulitha Wickrama MS K. A. S. Wickrama Ph.D Chalandra M. Bryant PhD 《Journal of youth and adolescence》2006,35(4):641-651
Using a sample of 20,000 adolescents (Add Health data), this study examined the influences of community poverty and race/ethnicity on adolescent obesity. Multilevel analyses revealed strong evidence for the unique influences of community poverty and race/ethnicity on adolescent obesity net of family characteristics. The prevalence of obesity is significantly higher in poor communities than in affluent communities; and it is higher among African Americans, Hispanics and Native Americans than among Whites. The interaction between race/ethnicity and community poverty indicates that race/ethnicity moderates the influence of community poverty on the prevalence of obesity. Although the prevalence of obesity is higher among minorities than among Whites, the influence of community poverty is stronger for Whites than for minorities, suggesting that unlike Whites, most minority groups may not accrue benefits of structural community advantages. The state of being overweight as the outcome variable provided essentially the same findings. The practical implications are discussed. 相似文献
84.
This study examined changes in extreme weight change attitudes and behaviors (exercise dependence, food supplements, drive for thinness, bulimia) among adolescent boys and girls over a 16 month period. It also investigated the impact of body mass index, puberty, body image, depression and positive affect on these attitudes and behaviors 16 months later. The participants were 847 young adolescents (411 boys, 436 girls). Participants completed questionnaires evaluating the above variables on three occasions, eight months apart. Girls obtained higher scores on exercise dependence, drive for thinness and bulimia. Changes in depression and body image importance were the strongest predictors of changes in these extreme attitudes and behaviors among boys; changes in depression, body dissatisfaction and body image importance were the strongest predictors for girls. The need for gender specific educational and intervention programs for adolescents are discussed.Marita McCabe PhD, Professor in Psychology in the School of Psychology, Deakin University, Melbourne, Australia. She has completed her PhD in 1981 on adolescent development, and has been completing research on various aspects of adolescent adjustment for 30 years. To whom correspondence should be addressed at 221 Burwood Highway, Burwood, Victoria 3125, Australia;Senior Lecturer in the School of Psychology, Deakin University, Melbourne Australia. She completed her PhD in 1990 on Childrens Language Development. In the last 10 years she has been researching body image concerns in adolescents and children 相似文献
85.
86.
Application of mRNA Expression Analysis to Human Blood Identification in Degenerated Samples that were False‐negative by Immunochromatography,, 下载免费PDF全文
Shusaku Matsumura M.S. Aya Matsusue Ph.D. Brian Waters M.S. Masayuki Kashiwagi M.D. Ph.D. Kenji Hara Ph.D. Shin‐ichi Kubo M.D. Ph.D. 《Journal of forensic sciences》2016,61(4):903-912
Forensic laboratories are often faced with cases in which methamphetamine hydrochloride‐mixed blood is unable to be identified as human blood by immunochromatography against human hemoglobin A0. The application of mRNA expression analysis to samples that showed a false‐negative with immunochromatography was investigated as an alternative approach that did not depend on the antigen–antibody reaction. Real‐time PCR was used to examine the expression levels of blood markers such as glycophorin A, spectrin beta, and hemoglobin beta. Hemoglobin beta was the only marker that was specifically detected in blood, while glycophorin A was useful for determining human specificity. Hemoglobin beta showed good detection sensitivity and was detectable in 37‐year‐old blood stains. Hemoglobin beta was exclusively detectable in methamphetamine hydrochloride‐mixed blood stains. Detergents and disinfectants did not significantly influence mRNA markers. The proposed mRNA expression analysis was suitable for human blood identification as an alternative method to immunochromatography. 相似文献
87.
Development of a Library Search‐Based Screening System for 3,4‐Methylenedioxymethamphetamine in Ecstasy Tablets Using a Portable Near‐Infrared Spectrometer 下载免费PDF全文
Kenji Tsujikawa Ph.D. Tadashi Yamamuro Ph.D. Kenji Kuwayama Ph.D. Tatsuyuki Kanamori Ph.D. Yuko T. Iwata Ph.D. Kazuna Miyamoto M.S. Fumiyo Kasuya Ph.D. Hiroyuki Inoue Ph.D. 《Journal of forensic sciences》2016,61(5):1208-1214
This is the first report on development of a library search‐based screening system for 3,4‐methylenedioxymethamphetamine (MDMA) in ecstasy tablets using a portable near‐infrared (NIR) spectrometer. The spectrum library consisted of spectra originating from standard substances as well as mixtures of MDMA hydrochloride (MDMA‐HCl) and diluents. The raw NIR spectra were mathematically pretreated, and then, a library search was performed using correlation coefficient. To enhance the discrimination ability, the wavelength used for the library search was limited. Mixtures of MDMA‐HCl and diluents were used to decide criteria to judge MDMA‐positive or MDMA‐negative. Confiscated MDMA tablets and medicinal tablets were used for performance check of the criteria. Twenty‐two of 27 MDMA tablets were truly judged as MDMA‐positive. Five false‐negative results may be caused by compounds not included in the library. No false‐positive results were obtained for medicinal tablets. This system will be a useful tool for on‐site screening of MDMA tablets. 相似文献
88.
Abdullah Alawadhi MSc Constantine Eliopoulos PhD Frederic Bezombes PhD 《Journal of forensic sciences》2023,68(4):1286-1291
The Middle East is one of the world regions that has frequently suffered from armed conflicts that resulted in mass burials. However, the detection of clandestine graves in such an arid environment by deploying remote sensing payload on unmanned aerial vehicles (UAVs) has received little attention. The present study used a UAV equipped with a thermal sensor aimed at narrowing down the search area of possible gravesites in the arid climate of Kuwait. The enclosed research area, which includes both control and experimental mass graves, was imaged for 18 months. The variation in topsoil temperature and soil moisture between the graves and their surroundings was evaluated. The results of the analysis demonstrated the effectiveness of thermal imaging techniques in detecting heat produced from buried sheep carcasses and detecting the change in grave soil moisture for our research environment for 7 and 10 months, respectively. The buried animals significantly influenced the topsoil temperature (p = 0.044), while the height from which the images were captured had an insignificant effect on the measured temperature within the range tested (p = 0.985). Furthermore, there was a negative correlation (−0.359) between grave temperature and the calculated soil moisture. The results from these cost- and time-effective search methods presented in this study confirm their potential for the detection of burial sites in an arid environment. 相似文献
89.
Kaitlyn B. Palmquist PhD Michael T. Truver PhD Elisa N. Shoff MS Alex J. Krotulski PhD Madeleine J. Swortwood PhD 《Journal of forensic sciences》2023,68(5):1643-1661
Fentanyl, fentanyl analogs, and other novel synthetic opioids (NSO), including nitazene analogs, prevail in forensic toxicology casework. Analytical methods for identifying these drugs in biological specimens need to be robust, sensitive, and specific. Isomers, new analogs, and slight differences in structural modifications necessitate the use of high-resolution mass spectrometry (HRMS), especially as a non-targeted screening method designed to detect newly emerging drugs. Traditional forensic toxicology workflows, such as immunoassay and gas chromatography mass spectrometry (GC–MS), are generally not sensitive enough for detection of NSOs due to observed low (sub-μg/L) concentrations. For this review, the authors tabulated, reviewed, and summarized analytical methods from 2010–2022 for screening and quantification of fentanyl analogs and other NSOs in biological specimens using a variety of different instruments and sample preparation approaches. Limits of detection or quantification for 105 methods were included and compared to published standards and guidelines for suggested scope and sensitivity in forensic toxicology casework. Methods were summarized by instrument for screening and quantitative methods for fentanyl analogs and for nitazenes and other NSO. Toxicological testing for fentanyl analogs and NSOs is increasingly and most commonly being conducted using a variety of liquid chromatography mass spectrometry (LC–MS)-based techniques. Most of the recent analytical methods reviewed exhibited limits of detection well below 1 μg/L to detect low concentrations of increasingly potent drugs. In addition, it was observed that most newly developed methods are now using smaller sample volumes which is achievable due to the sensitivity increase gained by new technology and new instrumentation. 相似文献
90.
Samantha Schiro PsyD Lisa S. Elwood PhD Thomas Streed PhD Aaron J. Kivisto PhD 《Journal of forensic sciences》2023,68(4):1259-1267
Forensic science professionals are routinely exposed to potentially traumatizing evidence. This study aimed to estimate the prevalence of occupational posttraumatic stress disorder (PTSD) among forensic science professionals, identify job-related correlates of PTSD symptoms, and examine the role of social support in mitigating PTSD symptomology. In response to recruitment through the American Academy of Forensic Sciences, the American Society of Crime Laboratory Directors, and Evidence Technology Magazine, 449 forensic science professionals participated in the current study. Results found that 73.5% (n = 330) of the overall sample experienced at least one work-related traumatic event consistent with meeting Criterion A for PTSD, and these rates were higher for field-based respondents (n = 203, 87.9%). The prevalence of past-month provisional PTSD was 21.6% for the full sample. Disaggregated PTSD rates were 29.0% and 14.5% for field-based and non-field-based respondents, respectively. These rates were 6- to 8-fold higher than the past-year prevalence of PTSD in the general US population, estimated to be 3.5%, and were found to be at least as high as those observed in prior epidemiological research with non-treatment seeking members of the US military deployed to war zones in Iraq and Afghanistan. Results further showed that social support was protective against PTSD symptomology. The high rates of occupational exposure to trauma and consequent PTSD symptomology observed in this large sample of forensic science professionals highlight the under-acknowledged psychological risks of these occupations and the need for enhanced attention to mental health resources for these professionals. 相似文献