66 research outputs found

    An antiproton driver for ICF propulsion

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    Inertial confinement fusion (ICF) utilizing an anitprotoncatalyzed target is discussed as a possible source of propulsion for rapid interplanetary manned space missions. The relevant compression, ignition, and thrust mechanisms are presented. Progress on an experiment presently in progress at the Phillips Laboratory, Kirtland AFB, NM to demonstrate proof-of-principle is reviewed

    Eureka and beyond: mining's impact on African urbanisation

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    This collection brings separate literatures on mining and urbanisation together at a time when both artisanal and large-scale mining are expanding in many African economies. While much has been written about contestation over land and mineral rights, the impact of mining on settlement, notably its catalytic and fluctuating effects on migration and urban growth, has been largely ignored. African nation-states’ urbanisation trends have shown considerable variation over the past half century. The current surge in ‘new’ mining countries and the slow-down in ‘old’ mining countries are generating some remarkable settlement patterns and welfare outcomes. Presently, the African continent is a laboratory of national mining experiences. This special issue on African mining and urbanisation encompasses a wide cross-section of country case studies: beginning with the historical experiences of mining in Southern Africa (South Africa, Zambia, Zimbabwe), followed by more recent mineralizing trends in comparatively new mineral-producing countries (Tanzania) and an established West African gold producer (Ghana), before turning to the influence of conflict minerals (Angola, the Democratic Republic of Congo and Sierra Leone)

    Intravesical Treatments of Bladder Cancer: Review

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    For bladder cancer, intravesical chemo/immunotherapy is widely used as adjuvant therapies after surgical transurethal resection, while systemic therapy is typically reserved for higher stage, muscle-invading, or metastatic diseases. The goal of intravesical therapy is to eradicate existing or residual tumors through direct cytoablation or immunostimulation. The unique properties of the urinary bladder render it a fertile ground for evaluating additional novel experimental approaches to regional therapy, including iontophoresis/electrophoresis, local hyperthermia, co-administration of permeation enhancers, bioadhesive carriers, magnetic-targeted particles and gene therapy. Furthermore, due to its unique anatomical properties, the drug concentration-time profiles in various layers of bladder tissues during and after intravesical therapy can be described by mathematical models comprised of drug disposition and transport kinetic parameters. The drug delivery data, in turn, can be combined with the effective drug exposure to infer treatment efficacy and thereby assists the selection of optimal regimens. To our knowledge, intravesical therapy of bladder cancer represents the first example where computational pharmacological approach was used to design, and successfully predicted the outcome of, a randomized phase III trial (using mitomycin C). This review summarizes the pharmacological principles and the current status of intravesical therapy, and the application of computation to optimize the drug delivery to target sites and the treatment efficacy

    Adolescent deviation and age

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    Traditional theories of delinquency causation generally fail to consider delinquency in the context of norms and age-role transitions peculiar to adolescence. Hence, in this study, an age-based theory of delinquency causation is developed, which assumes the importance of norms and roles specific to adolescence. This theory draws upon the assumption that socialization is recurrent, in contrast to the premises regarding socialization which underlie traditional theories of adolescent deviance. The recurrent model of socialization and that assumed by traditional theorists are discussed, and their implications for the causes of delinquent behavior are examined. Some effort is made to show that the recurrent model of socialization suggests an anomie of age as the basis for delinquent acts. It is suggested that this age-based anomie stems from conditions of normlessness associated with certain role transitions in adolescence and the pacing of these transitions. Further, it is suggested that certain groups are especially prone to an anomic age transition. The role transitions most likely to be subject to such anomic conditions and the adolescent subgroups most prone to experience anomie as a result of the pacing of their age-role transitions are identified .Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45260/1/10964_2005_Article_BF01537174.pd

    Hot spots policing effects on crime

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    In recent years, crime scholars and practitioners have pointed to the potential benefits of focusing crime prevention efforts on crime places. A number of studies suggest that there is significant clustering of crime in small places, or “hot spots,” that generate half of all criminal events. A number of researchers have argued that many crime problems can be reduced more efficiently if police officers focused their attention to these deviant places. The appeal of focusing limited resources on a small number of high-activity crime places is straightforward. If we can prevent crime at these hot spots, then we might be able to reduce total crime. Objectives: To assess the effects of focused police crime prevention interventions at crime hot spots. The review also examined whether focused police actions at specific locations result in crime displacement (i.e., crime moving around the corner) or diffusion (i.e., crime reduction in surrounding areas) of crime control benefits

    Changes in Burn Surgery Operative Volume and Metrics due to COVID-19

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    Due to COVID-19, hospitals underwent drastic changes to operating room policy to mitigate the spread of the disease. Given these unprecedented measures, we aimed to look at the changes in operative volume and metrics of the burn surgery service at our institution. A retrospective review was conducted for operative cases and metrics for the months of March to May for 2019, 2020, and 2021, which correspond with pre-COVID, early COVID (period without elective cases), and late COVID (period with resumed elective cases). Inclusion criteria were cases related to burns. Case types and operative metrics were compared amongst the three time periods. Compared to the hospital, the burn service had a smaller decrease in volume during early COVID (28.7% vs. 50.1%) and exceeded pre-pandemic volumes during late COVID (+21.8% vs. -4.6%). There was a significant increase in excision and grafting cases in early and late COVID periods (p \u3c .0001 and p \u3c .002). There was a significant decrease in laser scar procedures that persisted even during late COVID (p \u3c .0001). The projected and actual lengths of cases significantly increased and persisted into late COVID (p \u3c .01). COVID-19 related operating room closures led to an expected decrease in the number of operative cases. However, there was no significant decline in the number of burn specific cases. The elective cases were largely replaced with excision and grafting cases and this shift has persisted even after elective cases have resumed. This change is also reflected in increased operative times
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