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51.
Motorcyclists contribute significantly to road trauma around the world through the high incidence of serious injuries and fatalities. The role of roadside safety barriers in such trauma is an area of growing concern amongst motorcyclists, road authorities and road safety researchers and advocates. This paper presents a case series analysis of motorcyclists that were fatally injured following a collision with a roadside barrier during the period 2001–2006 in Australia and New Zealand. Injury profiles and severities are detailed, and associations with crash characteristics are investigated. It is shown that the thorax region had the highest incidence of injury and the highest incidence of maximum injury in fatal motorcycle-barrier crashes, followed by the head region. This is in contrast to fatal motorcycle crashes in all single- and multi-vehicle crash modes, where head injury predominates. The injury profiles of motorcyclists that slid into barriers and those that collided with barriers in the upright posture were similar. However, those that slid in were more likely to receive thorax and pelvis injuries. 相似文献
52.
Around one in three contained and restrained seriously injured occupants in single-vehicle pure rollover crashes receive a serious injury to the thorax. With dynamic rollover test protocols currently under development, there is a need to understand the nature and cause of serious thoracic injuries incurred in rollover events. This will allow decisions to be made with regards to adoption of a suitable crash test dummy and appropriate thoracic injury criteria in such protocols. Valid rollover occupant protection test protocols will lead to vehicle improvements that will reduce the high trauma burden of vehicle rollover crashes. This paper presents an analysis of contained and restrained occupants involved in single-vehicle pure rollover crashes that occurred in the United States between 2000 and 2009 (inclusive). Serious thoracic injury typology and causality are determined. A logistic regression model is developed to determine associations between the incidence of serious thoracic injury and the human, vehicle and environmental characteristics of the crashes. Recommendations are made with regards to the appropriate assessment of potential thoracic injury in dynamic rollover occupant protection crash test protocols. 相似文献
53.
Cholesterol itself has very few structural/chemical features suitable for real-time imaging in living cells. Thus, the advent
of dehydroergosterol [ergosta-5,7,9(11),22-tetraen-3β-ol, DHE] the fluorescent sterol most structurally and functionally similar
to cholesterol to date, has proven to be a major asset for real-time probing/elucidating the sterol environment and intracellular
sterol trafficking in living organisms. DHE is a naturally occurring, fluorescent sterol analog that faithfully mimics many
of the properties of cholesterol. Because these properties are very sensitive to sterol structure and degradation, such studies
require the use of extremely pure (>98%) quantities of fluorescent sterol. DHE is readily bound by cholesterol-binding proteins,
is incorporated into lipoproteins (from the diet of animals or by exchange in vitro), and for real-time imaging studies is
easily incorporated into cultured cells where it co-distributes with endogenous sterol. Incorporation from an ethanolic stock
solution to cell culture media is effective, but this process forms an aqueous dispersion of DHE crystals which can result
in endocytic cellular uptake and distribution into lysosomes which is problematic in imaging DHE at the plasma membrane of
living cells. In contrast, monomeric DHE can be incorporated from unilamellar vesicles by exchange/fusion with the plasma
membrane or from DHE-methyl-β-cyclodextrin (DHE-MβCD) complexes by exchange with the plasma membrane. Both of the latter techniques
can deliver large quantities of monomeric DHE with significant distribution into the plasma membrane. The properties and behavior
of DHE in protein-binding, lipoproteins, model membranes, biological membranes, lipid rafts/caveolae, and real-time imaging
in living cells indicate that this naturally occurring fluorescent sterol is a useful mimic for probing the properties of
cholesterol in these systems. 相似文献
54.
A method for visualizing manifold-valued medical image data is proposed. The method operates on images in which each pixel is assumed to be sampled from an underlying manifold. For example, each pixel may contain a high dimensional vector, such as the time activity curve (TAC) in a dynamic positron emission tomography (dPET) or a dynamic single photon emission computed tomography (dSPECT) image, or the positive semi-definite tensor in a diffusion tensor magnetic resonance image (DTMRI). A nonlinear mapping reduces the dimensionality of the pixel data to achieve two goals: distance preservation and embedding into a perceptual color space. We use multidimensional scaling distance-preserving mapping to render similar pixels (e.g., DT or TAC pixels) with perceptually similar colors. The 3D CIELAB perceptual color space is adopted as the range of the distance preserving mapping, with a final similarity transform mapping colors to a maximum gamut size. Similarity between pixels is either determined analytically as geodesics on the manifold of pixels or is approximated using manifold learning techniques. In particular, dissimilarity between DTMRI pixels is evaluated via a Log-Euclidean Riemannian metric respecting the manifold of the rank 3, second-order positive semi-definite DTs, whereas the dissimilarity between TACs is approximated via ISOMAP. We demonstrate our approach via artificial high-dimensional, manifold-valued data, as well as case studies of normal and pathological clinical brain and heart DTMRI, dPET, and dSPECT images. Our results demonstrate the effectiveness of our approach in capturing, in a perceptually meaningful way, important features in the data. 相似文献
55.
The short‐wavelength response of cadmium sulfide/cadmium telluride (CdS/CdTe) photovoltaic (PV) modules can be improved by the application of a luminescent down‐shifting (LDS) layer to the PV module. The LDS layer contains a mixture of fluorescent organic dyes that are able to absorb short‐wavelength light of λ < 540 nm, for which the PV module exhibited low external quantum efficiency (EQE), and re‐emit it at a longer wavelength (λ > 540 nm), where the solar cell EQE is high. Ray‐tracing simulations indicate that a mixed LDS layer containing three dyes could lead to an increase in the short‐circuit current density from Jsc = 19.8 mA/cm2 to Jsc = 22.9 mA/cm2 for a CdS/CdTe PV module. This corresponds to an increase in conversion efficiency from 9.6% to 11.2%. This indicates that a relative increase in the performance of a production CdS/CdTe PV module of nearly 17% can be expected via the application of LDS layers, possibly without any making any alterations to the solar cell itself. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
56.
Gregory G. Martin Danilo Landrock Avery L. McIntosh Sherrelle Milligan Kerstin K. Landrock Ann B. Kier John Mackie Friedhelm Schroeder 《Lipids》2020,55(4):309-327
Ad libitum-fed diets high in fat and carbohydrate (especially fructose) induce weight gain, obesity, and nonalcoholic fatty liver disease (NAFLD) in humans and animal models. However, interpretation is complicated since ad libitum feeding of such diets induces hyperphagia and upregulates expression of liver fatty acid binding protein (L-FABP)—a protein intimately involved in fatty acid and glucose regulation of lipid metabolism. Wild-type (WT) and L-fabp gene ablated (LKO) mice were pair-fed either high-fat diet (HFD) or high-fat/high-glucose diet (HFGD) wherein total carbohydrate was maintained constant but the proportion of glucose was increased at the expense of fructose. In LKO mice, the pair-fed HFD increased body weight and lean tissue mass (LTM) but had no effect on fat tissue mass (FTM) or hepatic fatty vacuolation as compared to pair-fed WT counterparts. These LKO mice exhibited upregulation of hepatic proteins in fatty acid uptake and cytosolic transport (caveolin and sterol carrier protein-2), but lower hepatic fatty acid oxidation (decreased serum β-hydroxybutyrate). LKO mice pair-fed HFGD also exhibited increased body weight; however, these mice had increased FTM, not LTM, and increased hepatic fatty vacuolation as compared to pair-fed WT counterparts. These LKO mice also exhibited upregulation of hepatic proteins in fatty acid uptake and cytosolic transport (caveolin and acyl-CoA binding protein, but not sterol carrier protein-2), but there was no change in hepatic fatty acid oxidation (serum β-hydroxybutyrate) as compared to pair-fed WT counterparts. 相似文献
57.
58.
OBJECTIVE: To determine if chronic administration of a low level of dehydroepiandrosterone-sulfate (DHEAS) (10 micrograms/ml drinking water) attenuates adiposity in male Osborne-Mendel rats fed low-fat (11% of kcals) vs high fat (46% of kcals) diets. DESIGN: Rats were randomly assigned to one of four treatment groups for 6 wk in this 2 x 2 factorial study. The main effects tested were diet (low vs high fat) and DHEAS (- or +). SUBJECTS: Male Osborne-Mendel rats (initial body wt approximately 265 g). MEASUREMENTS: Adipocyte mass, size and number from two major fat depots (retroperitoneal, epididymal); mass of one subcutaneous adipose depot (inguinal); serum levels of triglycerides, insulin, glucose and DHEAS; brown adipose tissue (BAT) mass; body weight gain, food and water consumption, and residual carcass composition. RESULTS: DHEAS treatment had no effect on weight gain, food consumption or water intake. DHEAS-treated rats fed the high-fat diet had smaller fat pads containing fewer adipocytes and less carcass lipid than the non DHEAS-treated rats fed the high-fat diet. In contrast, DHEAS-treated rats fed the low-fat diet had similar levels of adipose tissue mass and cellularity compared to control animals fed the low-fat diet. CONCLUSION: Administration of a low dose of DHEAS (10 micrograms/ml or 0.8 mg/kg body wt/d) in the drinking water of young male Osborne-Mendel rats fed a high-fat diet for 6 wk reduced carcass lipid, fat depot mass and retroperitoneal and epididymal adipocyte number compared to their high-fat-fed cohorts. In this study, the antiobesity effects of DHEAS were specific to the level of dietary fat used. 相似文献
59.
Optimization of the transient radiation from a dipole array 总被引:5,自引:0,他引:5
Pozar D. Yoon-Won Kang Schaubert D. McIntosh R. 《Antennas and Propagation, IEEE Transactions on》1985,33(1):69-75
The optimum solution for the transient radiation from a dipole array is derived in terms of the time-domain voltages which are required at the input terminals of dipoles in an array so that the amplitude of the transient radiated field at a specified timet_{0} and far-field positionr_{0} ,theta_{0}, phi_{0} is maximized. Constraints are placed on the energy and bandwidth of the input signal voltages with current restricted by Pocklington's equation. Further constraints on the sidelobe level are used to obtain a modified solution for suppressed sidelobes in the radiation pattern. Results of numerical optimization are presented, and the effects of scan angle, element spacing, and a sidelobe constraint on the optimization are discussed. 相似文献
60.
AK Malla RM Norman TS McLean S Cheng A Rickwood E McIntosh L Cortese K Diaz LP Voruganti 《Canadian Metallurgical Quarterly》1998,43(7):698-705
OBJECTIVES: To provide an overview of a comprehensive and integrated case-management program that incorporates principles of assertive community treatment and combines effective medical and psychosocial interventions and to present the results of a process and outcome evaluation of the program, with particular emphasis on its impact on service utilization and consumer satisfaction. METHOD: Data on demographic, clinical, and several outcome measures were collected on all patients who received care in the program for a minimum of 6 months. For process evaluation we assessed the extent to which the program adhered to its goals and satisfied the patients, their families, and community-service agencies. Outcome-evaluation data on the number and length of hospital admissions were compared for each subject with individual historical data for a period equal to the time spent in the program. In addition, relapses of psychotic symptoms that did not result in hospital admissions were calculated for each patient while in the program. RESULTS: Demographic, clinical, and treatment characteristics of clients show that the program has succeeded in maintaining its focus on providing services to relatively chronically ill patients with psychotic disorders over a mean period of 3 years. The process-evaluation data indicated a high level of satisfaction by patients, families, and other service agencies with the services received. Information on outcome variable showed that the program achieved significantly lower rates of hospital admissions and relapse of psychosis than expected. There was a highly significant reduction achieved in the utilization of inpatient hospital resources for patients receiving care in the program. Most of the inpatient service utilization was attributed to patients either who were resistant to treatment with antipsychotic agents or who refused to accept or comply with medication. CONCLUSIONS: It is possible to provide effective continuity of care from inpatient treatment to community adjustment for most individuals with psychotic disorders across the spectrum by blending hospital and community resources within an integrated case-management model of care. 相似文献