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41.
Shawna M. Brandle 《Journal of Political Science Education》2018,14(4):535-554
Traditional American Government textbooks are expensive and often unpopular with students. New technologies and Open Educational Resources (OERs) open up the potential for change, but questions of quality are ever present: can OERs really help students learn better, or are they just cheaper? I developed an OER based on original sources and compared student learning outcomes with the OER section to those in a free digital textbook section. While the OER I created did not work as well as I had hoped, I nonetheless developed a redesign of my course and my approach to teaching, which is the true benefit of adopting OERs. 相似文献
42.
Maywa Montenegro de Wit 《The Journal of peasant studies》2017,44(1):169-212
Faced with pressing climatic changes, scientific and industrial interests are vying to develop crops that can survive drought, floods and shifting pest regimes. Increasingly, they look for solutions in an unlikely place: the gene pools of wild plants. Crop wild relatives (CWR) – species closely related to crops, including their ancestors – offer breeders the allure of retracing the domestication bottleneck, infusing genomes of modern crops with ‘lost’ genetic variety. Yet wild relatives also confront threats from climate change, urbanization and expansion of industrial agri-food. Thus, CWR, seen as both salvational and threatened, have become an international conservation and food-security priority. It is my contention that, in their common project to harness wild-relative potential, conservation and breeding science are co-evolving to extend seed commodity relations into new spheres. I examine enclosures along two fronts: first within ‘systematic CWR conservation’, where ‘in situ’ approaches, typically regarded as empowering and sustainable alternatives to ‘ex situ’, instead may support a complementary system of value extraction; second, in breeding and biotechnology research, which produces new value for CWR while profoundly shaping upstream conservation priorities. An important finding is that although today’s ‘ex situ-centric’ complementarity favors dispossession, an ‘in situ-centric’ approach could foster democratic renewal of biocultural diversity. 相似文献
43.
Kevin J. Farrugia Ph.D. Danielle Hunter B.Sc. Clarice Wilson B.Sc. Stef Hay B.Sc. Paul Sherriffs B.Sc. Paul Deacon B.Sc. 《Journal of forensic sciences》2020,65(1):248-254
This study presents a number of pseudo-operational trials on plastic bags investigating the double- and co-fuming process of a one-step fluorescent cyanoacrylate (LumicyanoTM) in comparisons with the two-step process with basic yellow 40 (BY40) staining for the detection of latent fingermarks. The results demonstrate that both Lumicyano solution and dye contribute to the increased detection of latent fingermarks during the double-fuming process (trial 1). Co-fuming the Lumicyano solution and dye separately (at a concentration of 8%) but simultaneously was less effective than 8% Lumicyano (trial 2). Co-fuming Lumicyano 8% and an additional 8% Lumicyano dye by weight was more effective than Lumicyano 8% (trial 3), possibly due to increased fluorescent material deposition during co-fuming allowing for better visualization. The use of BY40 after Lumicyano resulted in a considerable increase in detected fingermarks. 相似文献
44.
Rosario Barranco M.D. Fiorella Caputo M.D. Davide Bedocchi M.D. Francesca Maria Elena Frigiolini M.D. Lara Castelletti M.D. Giulio Fraternali Orcioni M.D. Francesco Ventura M.D. Ph.D. 《Journal of forensic sciences》2020,65(1):314-317
Intravascular lymphoma (IVL) is a rare subtype of extranodal lymphomas that is characterized by the selective growth of neoplastic cells within the lumen of small vessels. Authors document the case of an unexpected death caused by an undiagnosed intravascular large B-cell lymphoma with multi-organ involvement, which had initially manifested as an infection and then as an unclarified central nervous system pathology. Histological examination showed a diffuse intravascular large B-cell brain lymphoma with prominent cerebral involvement. The relevance of the case report reveals the importance of an autopsy of an extremely rare and threatening pathology that in most cases is diagnosed only postmortem. As a result, the role of the forensic pathologist becomes particularly important. When specifically performing an in-depth autopsy evaluation with a specific histologic analysis, it is possible to identify the intravascular lymphoma and declare a more accurate cause of death. 相似文献
45.
46.
Jennifer Paola Pascali Ph.D. Diego Palumbo M.Sc. Federica Umani Ronchi Ph.D. Francesco Mari Ph.D. Alessia Fioravanti M.Sc. Elisabetta Bertol Ph.D. 《Journal of forensic sciences》2020,65(1):189-192
Through the measurement of ethyl glucuronide in hair (hETG), it is possible to assess chronic alcohol abuse over time. In this paper, we present a study on hETG in Italian prison inmates. Analyses were performed by LC-MS according to a previously published method. Results were evaluated using the cut-offs established by the Society of Hair Testing. Positives samples (ETG > 30 pg/mg) accounted for 6% of all subjects, with concentrations ranging from 42 pg/mg up to 270 pg/mg, abstinent subjects (ETG < 7 pg/mg) accounted for 88%, and moderate alcohol consumption (7 < ETG < 30 pg/mg) for 6% of the subjects. No females displayed ETG values above 30 pg/mg. Among positive samples, only two subjects did not declare heavy alcohol consumption and were found strongly positive at 210 and 270 pg/mg. To the best of our knowledge, this represents the first study on ETG hair concentration on prison inmates. 相似文献
47.
Youngmin Kim M.S. Won-sil Choi Ph.D. Byoungjun Jeon B.S. Tae Hyun Choi M.D. Ph.D. 《Journal of forensic sciences》2020,65(2):458-464
Cholesterol and squalene are fatty materials of latent fingermarks that can be utilized for dating methodologies and visualization techniques. Previous studies have suggested these compounds undergo degradation in fingermarks as a function of time (days) and light at ambient temperature. However, studies assessing how their composition changes at low and high temperatures over short periods of time (hours) have not been published previously. Here, we performed quantitative analysis of cholesterol and squalene in natural fingermark residue using PVDF membrane, after exposure to a range of temperatures (−20 to 100°C) for 4 and 8 h. We found that levels of both fatty materials remained constant at −20 to 60°C, but both showed significant reduction at 100°C, over short exposure times. These results indicate that cholesterol and squalene are detectable at −20 to 60°C, whereas at 100°C or higher, both are lost due to rapid thermal degradation. 相似文献
48.
Sierra F. Kaszubinski B.Sc. Jennifer L. Pechal Ph.D. Carl J. Schmidt M.D. Heather R. Jordan Ph.D. Mark E. Benbow Ph.D. Mariah H. Meek Ph.D. 《Journal of forensic sciences》2020,65(2):513-525
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. 相似文献
49.
Sabrina Zorbo M.S. Patrick P. J. M. H. Jeuniaux Ph.D. 《Journal of forensic sciences》2020,65(2):641-648
In the case of suspicious deaths, the technique of 1:1 taping is often used in Belgium. It consists of affixing a large number of adhesive tapes to the body of the victim. It is conventionally aimed at obtaining microtraces (e.g., fibers, hair) and is usually not used for DNA analysis. However, in some cases, DNA analysis of certain areas of interest identified on the 1:1 taping material can offer a last resort solution. The four-step method that is described in this article involves the selection of areas of interest on the body (Step 1), the selection of the corresponding tapes (Step 2), the decontamination of the tapes (Step 3), the selection of areas of interest on the tapes, for DNA sampling (Step 4). The method is illustrated by its successful application in four murder cases. In each case, DNA profiles of good quality could be identified, including profiles of persons different from the victim. 相似文献
50.
Wu-ting Tsai Ph.D. Chia-I Hu M.S. Chia-Yun Chang L.L.M. 《Journal of forensic sciences》2020,65(1):255-258
The horizontal displacement of the human body resulting from fatal fall from a height is an important variable commonly used to inversely determine the cause or identify other forensic aspects of the fall. When examining the horizontal displacement, the wind effect is generally ignored. This technical note reports analytical modeling of the falling process, utilizing previous measurements of wind force acting on the human body, for determining the functional relationship between the wind speed and the horizontal displacement in the falling process. The result reveals that it does not take extremely rare wind conditions to cause a considerable shift of the human body, highlighting the importance to consider wind as a factor in investigations of fatal falls. 相似文献