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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66290/1/j.1752-7325.1985.tb01140.x.pd

    PARASITES FROM HUMAN COPROLITES FROM MEXICO ZOONOTIC AND HUMAN PARASITES OF INHABITANTS OF CUEVA DE LOS MUERTOS CHIQUITOS, RIO ZAPE VALLEY, DURANGO, MEXICO.

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    We present the first reconstruction of the parasitoses among the people of the Loma San Gabriel culture, as represented by 36 coprolites excavated from the Cueva de los Muertos Chiquitos in Durango, Mexico. The coprolites date to approximately 1,400-yr-ago. Species identified based on eggs recovered include the trematode Echinostoma sp., the tapeworms Hymenolepis sp. and Dipylidium caninum, and the nematodes Ancylostoma duodenale, Enterobius vermicularis, and Trichuris trichiura. After rehydration and screening, 2 methods were used to recover eggs from these samples including spontaneous sedimentation and flotation. Samples were analyzed by 3 different laboratories for independent verification and comparison of methods. Spontaneous sedimentation resulted in the discovery of hymenolepidid eggs that were not found with flotation. Sedimentation was a more-sensitive indicator of prevalence as well. The modified method of flotation permitted estimation of egg concentration and resulted in the detection of a few specimens not found by sedimentation. The results of both methods showed that 19 (of 36) coprolites contained helminth eggs. Our results detected the presence of pathogenic helminths including hookworms and whipworms. The cestodes found do not cause severe pathology in humans. The early dates of hookworm and whipworm, relative to other findings in the southwest United States, indicate that these parasites arrived relatively late in prehistory in Arizona and New Mexico, probably moving into the area with travelers from Mesoamerica

    Argument-Driven Engineering in Middle School Science: An Exploratory Study of Changes in Engineering Identity Over an Academic Year

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    The goal of this study was to examine how the use of a new instructional model is related to changes in middle school students’ engineering identity. The intent of this instructional model, which is called argument-driven engineering (ADE), is to give students opportunities to design and critique solutions to meaningful problems using the core ideas and practices of science and engineering. The model also reflects current recommendations found in the literature for supporting the development or maintenance of engineering identity. This study took place in the context of an eighth-grade science classroom in order to explore how middle school students’ engineering identities change over time as they become more familiar with engineering core ideas and practices. One hundred students participated in this study. These students completed three design tasks during the school year that were created using the ADE instructional model. These students also completed a survey that was designed to measure two important aspects of an engineering identity (recognition and interest) at three different time points. The results of a hierarchical linear modeling analysis suggest that students’ ideas about how they view themselves and others view them in terms of engineering did not change over time and their reported interest decreased from one survey to the next. The difficulty of the design tasks and the ways teachers enacted the instructional model are proposed as potential explanations for this counterintuitive finding

    Before the Pandemic Ends: Making Sure This Never Happens Again

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    Introduction On 30 January 2020, the World Health Organization (WHO) declared a Global Health Emergency of international concern attendant to the emergence and spread of SARS-CoV-2, nearly two months after the first reported emergence of human cases in Wuhan, China. In the subsequent two months, global, national and local health personnel and infrastructures have been overwhelmed, leading to suffering and death for infected people, and the threat of socio-economic instability and potential collapse for humanity as a whole. This shows that our current and traditional mode of coping, anchored in responses after the fact, is not capable of dealing with the crisis of emerging infectious disease. Given all of our technological expertise, why is there an emerging disease crisis, and why are we losing the battle to contain and diminish emerging diseases? Part of the reason is that the prevailing paradigm explaining the biology of pathogen-host associations (coevolution, evolutionary arms races) has assumed that pathogens must evolve new capacities - special mutations – in order to colonize new hosts and produce emergent disease (e.g. Parrish and Kawaoka, 2005). In this erroneous but broadly prevalent view, the evolution of new capacities creates new opportunities for pathogens. Further, given that mutations are both rare and undirected, the highly specialized nature of pathogen-host relationships should produce an evolutionary firewall limiting dissemination; by those definitions, emergences should be rare (for a historical review see Brooks et al., 2019). Pathogens, however, have become far better at finding us than our traditional understanding predicts. We face considerable risk space for pathogens and disease that directly threaten us, our crops and livestock – through expanding interfaces bringing pathogens and hosts into increasing proximity, exacerbated by environmental disruption and urban density, fueled by globalized trade and travel. We need a new paradigm that explains what we are seeing. Additional section headers: The Stockholm Paradigm The DAMA Protocol A Sense of Urgency and Long-Term Commitment Reference

    Assessing the Cost of Global Biodiversity and Conservation Knowledge

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    Knowledge products comprise assessments of authoritative information supported by standards, governance, quality control, data, tools, and capacity building mechanisms. Considerable resources are dedicated to developing and maintaining knowledge products for biodiversity conservation, and they are widely used to inform policy and advise decision makers and practitioners. However, the financial cost of delivering this information is largely undocumented. We evaluated the costs and funding sources for developing and maintaining four global biodiversity and conservation knowledge products: The IUCN Red List of Threatened Species, the IUCN Red List of Ecosystems, Protected Planet, and the World Database of Key Biodiversity Areas. These are secondary data sets, built on primary data collected by extensive networks of expert contributors worldwide. We estimate that US160million(range:US160 million (range: US116–204 million), plus 293 person-years of volunteer time (range: 278–308 person-years) valued at US14million(rangeUS 14 million (range US12–16 million), were invested in these four knowledge products between 1979 and 2013. More than half of this financing was provided through philanthropy, and nearly three-quarters was spent on personnel costs. The estimated annual cost of maintaining data and platforms for three of these knowledge products (excluding the IUCN Red List of Ecosystems for which annual costs were not possible to estimate for 2013) is US6.5millionintotal(range:US6.5 million in total (range: US6.2–6.7 million). We estimated that an additional US114millionwillbeneededtoreachpre−definedbaselinesofdatacoverageforallthefourknowledgeproducts,andthatonceachieved,annualmaintenancecostswillbeapproximatelyUS114 million will be needed to reach pre-defined baselines of data coverage for all the four knowledge products, and that once achieved, annual maintenance costs will be approximately US12 million. These costs are much lower than those to maintain many other, similarly important, global knowledge products. Ensuring that biodiversity and conservation knowledge products are sufficiently up to date, comprehensive and accurate is fundamental to inform decision-making for biodiversity conservation and sustainable development. Thus, the development and implementation of plans for sustainable long-term financing for them is critical

    MULTI-TEMPORAL AND MULTI-PLATFORM AGRICULTURAL LAND COVER CLASSIFICATION IN SOUTHEASTERN MICHIGAN

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    ABSTRACT We investigated the capabilities of multi-temporal and multi-platform remotely sensed imagery to differentiate crop types in the 14,600 ha Upper Tiffin watershed in southeastern Michigan, a primarily agricultural area. We focused on extracting signatures for corn, soybeans, wheat, alfalfa, and grasses as the major crops for the area. Input data included Landsat 5 TM, Terra/MODIS, and ASTER imagery for different parts of the 2004 and 2005 agricultural growing season. MODIS was selected to address the problems with obtaining sufficient repeat coverage of Landsat data during the growing season. We used both pixel-based and object-oriented classification techniques to assess the value of different techniques in leading to more useful agricultural land cover classifications. To contrast with these classification techniques, we predicted crop distributions using MODIS NDVI time-series profiles. ASTER data were investigated to see if its additional high-resolution bands and its multi-angle instruments could provide supplementary classification information. State and Federal agencies are active in the Upper Tiffin study area because of known problems with sediment and nutrient loading in local waterways. The Natural Resource Conservation Service (NRCS), part of the United States Department of Agriculture, used the results to understand how different land uses were affecting local water quality, and how the problems could be addressed
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