Land grabbing in Latin America and the Caribbean

Land grabbing has gained momentum in Latin America and the Caribbean during the past decade. The phenomenon has taken different forms and character as compared to processes that occur in other regions of the world, especially Africa. It puts into question some of the assumptions in the emerging literature on land grabbing, suggesting these are too food-centered/too food crisis-centered, too land-centred, too centred on new global food regime players – China, South Korea, Gulf States and India – and too centred on Africa. There are four key mechanisms through which land grabbing in Latin American and the Caribbean has been carried out: food security initiatives, energy/fuel security ventures, other climate change mitigation strategies, and recent demands for resources from newer hubs of global capital. The hallmark of land grabbing in the region is its intra-regional character: the key investors are (Trans-)Latin American companies, often in alliance with international capital and the central state. Initial evidence suggests that recent land investments have consolidated the earlier trend away from (re)distributive land policies in most countries in the region, and are likely to result in widespread reconcentration of land and capital.     

Rethinking Timing of First Sex and Delinquency

The relation between timing of first sex and later delinquency was examined using a genetically informed sample of 534 same-sex twin pairs from the National Longitudinal Study of Adolescent Health, who were assessed at three time points over a 7-year interval. Genetic and environmental differences between families were found to account for the association between earlier age at first sex and increases in delinquency. After controlling for these genetic and environmental confounds using a quasi-experimental design, earlier age at first sex predicted lower levels of delinquency in early adulthood. The current study is contrasted with previous research with non-genetically informative samples, including Armour and Haynie (2007, Journal of Youth and Adolescence, 36, 141–152). Results suggest a more nuanced perspective on the meaning and consequences of adolescent sexuality than is commonly put forth in the literature.

利用aroA基因建立鸡传染性鼻炎PCR诊断方法

利用aroA基因设计了1对引物,分别对10株标准副鸡嗜血杆菌(HPG)菌株、14株分离的HPG菌株进行PCR扩增,结果均得到了与预期大小一致的片段,而对10株非HPG菌株和3株病毒进行扩增则无相应片段产生;该PCR能检测出10个菌细胞.与常规PCR方法相比,aroA-PCR的敏感性更高.     

Patterns of Young Adult Social Roles Transitions Across 24 Months and Subsequent Substance Use and Mental Health

Journal of Youth and Adolescence - Young adults experience social role transitions across multiple life domains, and a deeper understanding of the ways in which these simultaneous transition...     

Evaluating Bioinformatic Pipeline Performance for Forensic Microbiome Analysis*,†,‡

Microbial communities have potential evidential utility for forensic applications. However, bioinformatic analysis of high-throughput sequencing data varies widely among laboratories. These differences can potentially affect microbial community composition and downstream analyses. To illustrate the importance of standardizing methodology, we compared analyses of postmortem microbiome samples using several bioinformatic pipelines, varying minimum library size or minimum number of sequences per sample, and sample size. Using the same input sequence data, we found that three open-source bioinformatic pipelines, MG-RAST, mothur, and QIIME2, had significant differences in relative abundance, alpha-diversity, and beta-diversity, despite the same input data. Increasing minimum library size and sample size increased the number of low-abundant and infrequent taxa detected. Our results show that bioinformatic pipeline and parameter choice affect results in important ways. Given the growing potential application of forensic microbiology to the criminal justice system, continued research on standardizing computational methodology will be important for downstream applications.