241 research outputs found

    An appraisal of nutrient supplies available for tree growth in a pumice soil

    Get PDF
    Chemical analyses have confirmed and explained the results of an earlier pot trial in which the availability of major nutrients in six pumice ash layers of Kaingaroa silty sand was assessed by the growth of radiata pine seedlings. Almost all of the tree-available P is found in the present topsoil: the quantities-of P that occur in two buried soils (Waimihia and Rotoma ashes) are almost entirely in the form of organic P which is apparently very resistant to breakdown due to complexing with allophane. The N in these layers is similarly unavailable. The mineral layers, about 4 ft in thickness (Taupo pumice and lapilli), which lie between the present topsoil and the uppermost buried soil, are very low in total N and P and exchangeable Mg, but relatively high in exchangeable K. Only the lower buried soil contains a reasonable quantity of exchangeable Mg and has a Mg : K ratio in favour of Mg

    A Novel Modelling Technique for Blast Analysis of Steel-Concrete Composite Panels

    Get PDF
    AbstractBlast resistant structures usually undergo large plastic deformation and absorb energy before collapse. There are many structural forms that have improved blast resistance are reported in literature. Among these, steel-concrete composite panel has been considered as extremely resilient to blast loading. Conventionally, steel-concrete composite panels are analysed using solid element model for plates, concrete as well as shear connectors. In this paper, a novel modelling technique is proposed for analysis of steel-concrete composite panels under blast loading. As per the proposed technique, shell, solid and link elements are used to model cover plates, concrete and shear connector respectively. Validation and performance studies are carried out with a problem available in literature. The proposed model is found to be better with less demand on modelling requirements. It is also computationally efficient, while retaining the accuracy of results. Parametric studies are carried out using the proposed model on steel-concrete composite panel with through-through connectors subjected to air blast loading. Steel plate thickness, concrete core thickness, connector spacing and diameter of connectors are varied to study their influence on the response behaviour of the panel. It is observed from the study that connector diameter and spacing and core thickness significantly affect the response than the plate thickness

    Displaced but not replaced: the impact of e-learning on academic identities in higher education.

    Get PDF
    Challenges facing universities are leading many to implement institutional strategies to incorporate e-learning rather than leaving its adoption up to enthusiastic individuals. Although there is growing understanding about the impact of e-learning on the student experience, there is less understanding of academics’ perceptions of e-learning and its impact on their identities. This paper explores the changing nature of academic identities revealed through case study research into the implementation of e-learning at one UK university. By providing insight into the lived experiences of academics in a university in which technology is not only transforming access to knowledge but also influencing the balance of power between academic and student in knowledge production and use, it is suggested that academics may experience a jolt to their ‘trajectory of self’ when engaging with e-learning. The potential for e-learning to prompt loss of teacher presence and displacement as knowledge expert may appear to undermine the ontological security of their academic identity

    Effects of Acrylic Restorations on the Periodontium of Monkeys

    Full text link
    Replanted teeth that had an acrylic restoration in the middle third of their roots were studied from three days to six months after grafting. The study revealed that the acrylic obturator elicited epithelial proliferation, fibrous encapsulation, moderate chronic inflammation, and adjacent alveolar bone loss.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68162/2/10.1177_00220345720510052201.pd

    Qubit Disentanglement and Decoherence via Dephasing

    Full text link
    We consider whether quantum coherence in the form of mutual entanglement between a pair of qubits is susceptible to decay that may be more rapid than the decay of the coherence of either qubit individually. An instance of potential importance for solid state quantum computing arises if embedded qubits (spins, quantum dots, Cooper pair boxes, etc.) are exposed to global and local noise at the same time. Here we allow separate phase-noisy channels to affect local and non-local measures of system coherence. We find that the time for decay of the qubit entanglement can be significantly shorter than the time for local dephasing of the individual qubits.Comment: REVTeX, 9 pages, 1 figure, v2 with minor changes, reference adde

    The Impact and Cost-Effectiveness of a Four-Month Regimen for First-Line Treatment of Active Tuberculosis in South Africa.

    Get PDF
    BACKGROUND: A 4-month first-line treatment regimen for tuberculosis disease (TB) is expected to have a direct impact on patient outcomes and societal costs, as well as an indirect impact on Mycobacterium tuberculosis transmission. We aimed to estimate this combined impact in a high TB-burden country: South Africa. METHOD: An individual based M. tb transmission model was fitted to the TB burden of South Africa using a standard TB natural history framework. We measured the impact on TB burden from 2015-2035 of introduction of a non-inferior 4-month regimen replacing the standard 6-month regimen as first-line therapy. Impact was measured with respect to three separate baselines (Guidelines, Policy and Current), reflecting differences in adherence to TB and HIV treatment guidelines. Further scenario analyses considered the variation in treatment-related parameters and resistance levels. Impact was measured in terms of differences in TB burden and Disability Adjusted Life Years (DALYs) averted. We also examined the highest cost at which the new regimen would be cost-effective for several willingness-to-pay thresholds. RESULTS: It was estimated that a 4-month regimen would avert less than 1% of the predicted 6 million person years with TB disease in South Africa between 2015 and 2035. A similarly small impact was seen on deaths and DALYs averted. Despite this small impact, with the health systems and patient cost savings from regimen shortening, the 4-month regimen could be cost-effective at 436[NA,5983](mean[range])permonthatawillingness−to−paythresholdofoneGDPpercapita(436 [NA, 5983] (mean [range]) per month at a willingness-to-pay threshold of one GDP per capita (6,618). CONCLUSION: The introduction of a non-inferior 4-month first-line TB regimen into South Africa would have little impact on the TB burden. However, under several scenarios, it is likely that the averted societal costs would make such a regimen cost-effective in South Africa

    Whole genome analysis of a schistosomiasis-transmitting freshwater snail

    Get PDF
    Biomphalaria snails are instrumental in transmission of the human blood fluke Schistosoma mansoni. With the World Health Organization's goal to eliminate schistosomiasis as a global health problem by 2025, there is now renewed emphasis on snail control. Here, we characterize the genome of Biomphalaria glabrata, a lophotrochozoan protostome, and provide timely and important information on snail biology. We describe aspects of phero-perception, stress responses, immune function and regulation of gene expression that support the persistence of B. glabrata in the field and may define this species as a suitable snail host for S. mansoni. We identify several potential targets for developing novel control measures aimed at reducing snail-mediated transmission of schistosomiasis

    The Clinical Sequencing Evidence-Generating Research Consortium: Integrating Genomic Sequencing in Diverse and Medically Underserved Populations

    Get PDF
    The Clinical Sequencing Evidence-Generating Research (CSER) consortium, now in its second funding cycle, is investigating the effectiveness of integrating genomic (exome or genome) sequencing into the clinical care of diverse and medically underserved individuals in a variety of healthcare settings and disease states. The consortium comprises a coordinating center, six funded extramural clinical projects, and an ongoing National Human Genome Research Institute (NHGRI) intramural project. Collectively, these projects aim to enroll and sequence over 6,100 participants in four years. At least 60% of participants will be of non-European ancestry or from underserved settings, with the goal of diversifying the populations that are providing an evidence base for genomic medicine. Five of the six clinical projects are enrolling pediatric patients with various phenotypes. One of these five projects is also enrolling couples whose fetus has a structural anomaly, and the sixth project is enrolling adults at risk for hereditary cancer. The ongoing NHGRI intramural project has enrolled primarily healthy adults. Goals of the consortium include assessing the clinical utility of genomic sequencing, exploring medical follow up and cascade testing of relatives, and evaluating patient-provider-laboratory level interactions that influence the use of this technology. The findings from the CSER consortium will offer patients, healthcare systems, and policymakers a clearer understanding of the opportunities and challenges of providing genomic medicine in diverse populations and settings, and contribute evidence toward developing best practices for the delivery of clinically useful and cost-effective genomic sequencing in diverse healthcare settings

    Track D Social Science, Human Rights and Political Science

    Full text link
    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138414/1/jia218442.pd
    • …
    corecore