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• Providing a newly exploited trace DNA extraction platform based on magnetic bead-based method. • Establishing an automatic and efficient detection system for trace DNA. • The fingerprint materials were successfully dissected in the self-developed automatic detection system. The analysis of trace DNA is a crucial component in forensic applications. Biological materials containing low-level DNA collected at crime scenes, such as fingerprints, can be valuable as evidence. Automatic detection of biological samples has been largely embraced in forensic applications to meet the increasing throughput requirements. However, the amount of DNA automatically retrieved from trace evidence often tends to be small and unstable, ultimately resulting in poor detection of DNA profiles. Thus, in this work, we introduced a robust DNA extraction and purification platform named Bionewtech® BN3200 (Bionewtech®, Shanghai, China) with the goal of constructing a rapid automatic detection system for trace DNA. The establishment of automatic detection system for trace DNA mainly encompassed two parts: assessing the sensitivity of automatic extraction platform and screening the optimal short tandem repeat (STR) typing kit. The sensitivity of Bionewtech® BN3200 platform based on Ultra-sensitive DNA Extraction kit was initially estimated, demonstrating that this extraction platform might contain large potential in the trace DNA extraction. For the amplification part, three sets of commercial multiplex STR typing kits were selected as candidates, and the amplified products were further genotyped on the Applied Biosystems 3500xl Genetic Analyzer. After comparation, SiFa™ 23 Plex Kit was determined as the most suitable amplification system for trace DNA. Eventually, the newly exploited trace DNA detection system was successfully implemented in the detection of fingerprints derived from glass surfaces with the five-seconds contact time. As a result, the DNA recovered from the fingerprints fluctuated approximately from 57.60 pg to 18.05 ng, in addition, over 70% of the total STR loci were detected in 75% of the fingerprint samples. [ABSTRACT FROM AUTHOR]

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Quantifying the urban landscape pattern and its change is fundamental for monitoring and assessing the ecological and socio-economic consequences of urbanization. Using Indian Remote Sensing Panchromatic (IRS-PAN) imagery of 2002 and combining gradient analysis with landscape metrics, we compared the landscape patterns between metropolises and small-sized cities with increasing grain size. Landscape metrics were computed along a 51 × 9 km transect cutting across Shanghai and a 16 × 2 km transect cutting across Zhangjiagang with a moving window. The results showed that fragmentation indices (patch density (PD), total edge (TE), landscape division (LD)) in land use transects of the two cities had many similarities, indicating the common characteristics of urbanization in different-sized cities. There were, however, some striking dissimilarities between the two cities, which did not support the hypothesis that PD increases exponentially along a landscape modification gradient. These differences may have three explanations: the proportion of urban roads area, the width of urban roads and land use change in suburban and rural areas. The proportion of urban road area and the width of urban roads, which should be considered in future research, are two main factors that have been identified to influence the landscape pattern analysis. In younger and smaller cities, spatial competition between local interest groups and imperfect land managerial systems result in an increase in fragmentation in the suburbs, and policymakers should pay more attention to future city planning and management. A bridge linking the urbanization landscape pattern and the process of urban fragmentation will be a key to urban landscape studies and planning. [ABSTRACT FROM AUTHOR]