油樟叶挥发油对三种真菌的抗菌效果

为探讨油樟叶挥发油对须毛癣菌、犬小孢子菌和石膏小孢子菌的抑制活性及其作用机理,采用RPMI 1640液体培养基倍比稀释和沙氏琼脂平板稀释培养计数法分别检测油樟叶挥发油对这3种真菌的最小抑菌浓度(MIC)和最小杀菌浓度(MFC);并绘制体外杀菌曲线,观察MIC浓度下油樟叶挥发油对3种真菌的动态杀菌过程;透射电镜下观察油樟叶挥发油在MIC浓度下对3种真菌超微结构的影响。结果显示,油樟叶挥发油对3种真菌的MIC和MFC值均为3.125μL/mL;杀菌曲线表明,作用的前12h内油樟叶挥发油对3种真菌的杀菌作用最强,随后杀菌作用降低;电镜下对照组的3种真菌形态正常,在MIC浓度下,3种真菌原有的细胞器模糊不清、溶解或消失。试验证实,油樟叶挥发油对3种真菌具有较强的杀菌作用,其杀菌机理为破坏真菌的细胞器。     

DEVELOPMENTAL PATTERNS OF ALCOHOL USE IN RELATION TO THE PERSISTENCE AND DESISTANCE OF SERIOUS VIOLENT OFFENDING AMONG AFRICAN AMERICAN AND CAUCASIAN YOUNG MEN*

This study examined the association of alcohol use with the persistence and desistance of serious violent offending among African American and Caucasian young men from adolescence into emerging adulthood. Five violence groups were defined: nonviolent, late‐onsetters, desisters, persisters, and one‐time offenders. We examined alcohol use trajectories for these groups spanning 12 through 24/25 years of age using a four‐piecewise linear growth model s 12–14, 14–18, 18–21, and 21–24/25 years of age. The persisters and desisters reported the highest levels of drinking at 13 years of age. From 14 to 18 years old, however, the late‐onsetters showed a higher rate of increase in drinking, compared with the persisters and desisters. Starting at 18 years of age, the desisters’ drinking trajectory started to resemble that of the nonviolent group, who showed the highest rate of increase in drinking during emerging adulthood. By 24/25 years of age, the persisters could not be distinguished from the late‐onsetters, but they were lower than the nonviolent and one‐timer groups in terms of their drinking. At 24/25 years old, the desisters were not significantly different from the other violence groups, although they seemed most similar to the nonviolent and one‐timer groups. We found no evidence that the association between drinking and violence differed for African Americans and Caucasians. The findings suggest that yearly changes in alcohol use could provide important clues for preventing violent offending.     

STR melting curve analysis as a genetic screening tool for crime scene samples

In this proof-of-concept study, high-resolution melt curve (HRMC) analysis was investigated as a postquantification screening tool to discriminate human CSF1PO and THO1 genotypes amplified with mini-STR primers in the presence of SYBR Green or LCGreen Plus dyes. A total of 12 CSF1PO and 11 HUMTHO1 genotypes were analyzed on the LightScanner HR96 and LS-32 systems and were correctly differentiated based upon their respective melt profiles. Short STR amplicon melt curves were affected by repeat number, and single-source and mixed DNA samples were additionally differentiated by the formation of heteroduplexes. Melting curves were shown to be unique and reproducible from DNA quantities ranging from 20 to 0.4 ng and distinguished identical from nonidentical genotypes from DNA derived from different biological fluids and compromised samples. Thus, a method is described which can assess both the quantity and the possible probative value of samples without full genotyping.     

黏杆菌素对两种诱导多重耐药革兰氏阴性杆菌的体外抗菌活性

为评价黏杆菌素对兽医临床常见的多重耐药铜绿假单胞杆菌和大肠杆菌的抗菌作用,以微量肉汤稀释法对2种诱导多重耐药菌株进行最低抑菌浓度和最小杀菌浓度测定;采用菌落计数法绘制黏杆菌素对2种诱导多重耐药菌株的时间-杀菌曲线。结果表明,黏杆菌素对铜绿假单胞杆菌和大肠杆菌的最低抑菌浓度分别为2和0.25μg/mL,最小杀菌浓度分别为2和0.5μg/mL。黏杆菌素在0.5、2、4、8、16倍最低抑菌浓度下,对多重耐药大肠杆菌不同时间点的杀菌速率差异显著(P<0.05),呈现浓度依赖性;对铜绿假单胞杆菌呈现部分浓度依赖性。黏杆菌素在2倍最低抑菌浓度下,多重耐药大肠杆菌和铜绿假单胞杆菌菌量在2h内显著下降,在4倍最低抑菌浓度下可在8h内将大肠杆菌全部杀死,在4h内将铜绿假单胞杆菌全部杀死。说明黏杆菌素对诱导多重耐药铜绿假单胞杆菌和大肠杆菌具有强效、速效的杀菌作用。     

PARTICIPATION AND FREQUENCY DURING CRIMINAL CAREERS ACROSS THE LIFE SPAN*

Recent advances and debates surrounding general and developmental as well as static and dynamic theories of crime can be traced to the 1986 National Academy of Science's Report on criminal careers and the discussion it generated. A key point of contention has been regarding the interpretation of the age–crime curve. According to Gottfredson and Hirschi (1986), the decline in the age–crime curve in early adulthood reflects decreasing individual offending frequency (λ) after the peak. Blumstein et al. (1986) claimed that the decline in the aggregate age–crime curve also could be attributable to the termination of criminal careers, and the average value of l could stay constant (or increase with age) for those offenders who remain active after that peak. Using data from the Criminal Career and Life Course Study—including information on criminal convictions across 60 years of almost 5,000 persons convicted in the Netherlands—and applying a two-part growth model that explicitly distinguishes between participation and frequency, the study outlined in this article assessed the participation–frequency debate. Results suggest that the decline in the age–crime curve in early adulthood reflects both decreasing individual offending participation and frequency after the peak, that the probabilities of participation and frequency are significantly related at the individual level, and that sex and marriage influence both participation and frequency.     

发展循环经济走出两难困境

本文从分析环境库兹涅茨曲线着手,指出循环经济是包括中国在内的发展中国家实现环境保护与经济发展双赢的重要途径。作者分析了循环经济的渊源、模式和3R原则,并针对我国国情,从政府、企业、学术界三个层面提出了对策建议。     

Alcohol Use, Outcome Expectancies, and HIV Risk Status among American Indian Youth: A Latent Growth Curve Model with Parallel Processes

Alcohol use is cited as a risk factor for exposure to HIV infection through risky sexual behavior, especially among adolescents. From Social Cognitive Theory, positive outcome expectancies about the use of alcohol have often been presented as a critical aspect of alcohol use. Yet little is known about how they might be related to different aspects of HIV risk. Using latent growth curve modeling with data from 292 American Indian youth across seven years, both alcohol use and positive expectancies increased significantly; a lower-risk group showed significantly slower increases in both. Changes in alcohol use and outcome expectancies were significantly interrelated, providing support for reciprocal influence between the two constructs. Positive alcohol outcome expectancies may provide a preventive intervention point worthy of further consideration as influencing alcohol use and lowering HIV sexual risk among adolescents.Associate Professor at the University of Colorado at Denver and Health Sciences Center. She received her Ph.D. in Community Psychology from Michigan State University. Her major research interests are adolescent development among minority youth with an emphasis on positive and problem behaviors.Associate Professor at the University of Colorado at Denver and Health Sciences Center. She received her Ph.D. in Social Psychology from the University of Michigan. Her major research interests are in areas of American Indian mental health and services research.Assistant Professor at the University of Colorado at Denver and Health Sciences Center. She received her Ph.D. in Sociology from the University of Michigan. Her primary research interests are in demography and contextual effects of individual health behavior, with a special emphasis on adolescent development.In addition to the above people, the Project Team included Sonia Bauduy, Cathy A.E. Bell, Cecelia K. Big Crow, Dedra Buchwald, Nichole Cottier, Amy D. Dethlefsen, Ann Wilson Frederick, Ellen M. Keane, Shelly Hubing, Natalie Murphy, Angela Sam, Jennifer Settlemire, Jennifer Truel, and Frankee White Dress.     

谈弹匣弧形部擦划痕迹的形成及变化

弹匣弧形部擦划痕迹是射手在以压推方式向弹匣内压装枪弹过程中,弹壳体与弹匣弧形部内边棱相摩擦而形成的痕迹。由于射手向弹匣内压装枪弹的方式、习惯、用力大小等因素不同,形成痕迹的位置、深浅、长短、宽窄、倾斜角度等也就有所不同,有的甚至不留下痕迹或很少留下痕迹。弹匣弧形部擦划痕迹具有一定的稳定性,是认定枪支的重要痕迹特征。     

用熔解曲线法分析插入/缺失多态性和Y染色体SNPs多态性

随着单核苷酸多态性SNPs (SingleNucleotidePolymorphisms)及插入 /缺失多态性Indels (Insertion/Dele tion)的分型技术研究的深入 ,SNPs和Indels在法医学上的应用将受到深刻的影响。本文研究和探讨Indels的分型方法 ,通过测定扩增DNA片段在溶液中的溶解曲线图确定每个样品的基因型 ,称为溶解曲线Indels基因分型方法(McI/D)。溶解曲线图由被测样品DNA片段的特殊溶解温度组成 ,扩增结果直接由仪器分析不需要繁杂的PCR后期操作。     

What explains the dynamics of citizens’ satisfaction with democracy? An integrated framework for panel data

Literature on political support broadly offers three micro-level models: socio-economic status, democratic process evaluations, and political performance evaluations explain people's differences in satisfaction with democracy. While tests show that these explanations complement each other, we do not know how. We combine for the first time all three models into one common longitudinal framework by explicitly considering aspects of time. We argue that relatively stable factors, such as socio-economic status, only explain general levels, whereas more time-sensitive factors, such as evaluations, explain differences between citizens at specific points in time. The results of latent growth curve modelling applied to nine-wave panel data support our general hypothesis of a common longitudinal framework. These results also show that economic evaluations play a prominent role as do some (but not all) electoral results. The findings have theoretical and methodological implications, and they offer a new perspective on the meaning of ’satisfaction with democracy’.