334 research outputs found

    Application of geospatial analysis in health research: a systematic review of methodological aspects of studies on violence against children and young people

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    Background: Geographical variation exists in violence experienced by children and young people; however, there is limited research applying geospatial techniques to study this variation, and the methodological quality of this body of work is unclear. Objective: This study aimed to review the application of geospatial analysis in research on violence against children (VAC) and evaluate how essential methodological aspects are reported. Methods: Twelve databases were searched for studies on VAC using geospatial techniques. Two independent reviewers screened the papers for eligibility. Findings were narratively synthesised. Results: Sixty studies were included. Six studies estimated the prevalence of VAC and 54 investigated the associations between VAC and covariates. Most studies were conducted in the US (68 %), and the broad definition of ‘child maltreatment’ (53 %) was the most common form of violence explored. Most studies (83 %) used administrative data, whereas 23 % used an ecological study design to estimate the associations between risk factors and official reports of VAC. Frequentist modelling approaches were used in 54 % of the studies, and 47 % investigated VAC at census tract level. Model fit metrics were reported in 69 % of studies. Conclusions: Current knowledge of the geographical distribution of VAC is severely limited because of the reliance on administrative data, which vastly underestimates the prevalence of VAC compared with self-reports and poor reporting of quality characteristics. There is a huge opportunity for applying geospatial methods in VAC research in diverse geographic contexts. Future research must adopt rigorous and standardised approaches to model fitting and validation and make better use of self-reported data

    Bern-Kosower Rule for Scalar QED

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    We derive a full Bern-Kosower-type rule for scalar QED starting from quantum field theory: we derive a set of rules for calculating SS-matrix elements for any processes at any order of the coupling constant. Gauge-invariant set of diagrams in general is first written in the worldline path-integral expression. Then we integrate over x(τ)x(\tau), and the resulting expression is given in terms of correlation function on the worldline <x(τ)x(τ)>\left< x(\tau) x(\tau') \right>. Simple rules to decompose the correlation function into basic elements are obtained. Gauge transformation known as integration by parts technique can be used to reduce the number of independent terms before integration over proper-time variables. The surface terms can be omitted provided the external scalars are on-shell. Also, we clarify correspondence to the conventional Feynman rule, which enabled us to avoid any ambiguity coming from the infinite dimensionality of the path-integral approach.Comment: 38pages, 18 Postscript figures, uses epsf.st

    Road junction configurations and the severity of traffic accidents in Japan

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    In many countries, 40–60% of the traffic accidents occur at junctions, making the reduction of junction accidents paramount to achieving UN Sustainable Development Goals. In Japan, the road safety guidelines specify the proximity between junctions and non-perpendicular angles at junctions as the two main risk factors behind junction accidents, yet their impact remains understudied. Using binomial logistic regression models, this study investigates the impact of junction intervals and junction angles on the severity of traffic accidents. The study found that, in general, (1) shorter intervals between adjacent junctions helps reduce the risk of serious accidents, which is the opposite of the current road safety guidelines in Japan, and (2) results from the junction angle analysis were mixed but there was no evidence that the roads should meet at a right angle to reduce traffic accidents. Some types of accidents also returned a non-linear curve, e.g., vehicle-to-vehicle collisions at four-armed junctions involving a driver aged 65 years and over have the highest risk of fatal/serious accidents when adjacent junctions were 32 m apart, and the risk reduces at a shorter or longer interval. These results suggest that the current road safety guidelines require updating to improve road safety around junctions

    Electronic structure investigation of CeB6 by means of soft X-ray scattering

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    The electronic structure of the heavy fermion compound CeB6 is probed by resonant inelastic soft X-ray scattering using photon energies across the Ce 3d and 4d absorption edges. The hybridization between the localized 4f orbitals and the delocalized valence-band states is studied by identifying the different spectral contributions from inelastic Raman scattering and normal fluorescence. Pronounced energy-loss structures are observed below the elastic peak at both the 3d and 4d thresholds. The origin and character of the inelastic scattering structures are discussed in terms of charge-transfer excitations in connection to the dipole allowed transitions with 4f character. Calculations within the single impurity Anderson model with full multiplet effects are found to yield consistent spectral functions to the experimental data.Comment: 9 pages, 4 figures, 1 table, http://link.aps.org/doi/10.1103/PhysRevB.63.07510

    Retear of anterior cruciate ligament grafts in female basketball players: a case series

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    <p>Abstract</p> <p>Background</p> <p>Incidence of anterior cruciate ligament (ACL) injuries in young female basketball players is higher than that in male basketball players. Graft retears are more frequent with the increasing number of ACL reconstructions. The present study aimed to examine the incidence of retears in competitive female basketball players.</p> <p>Methods</p> <p>Sixty-four female basketball players (aged 12 to 29 years) who underwent primary anatomic double-bundle ACL reconstruction using hamstring grafts participated in the study. We investigated incidence, mechanism, and patient characteristics of ACL graft retears. Mann-Whitney <it>U </it>test was used for statistical analysis, and the level of significance was determined at <it>P </it>< 0.05.</p> <p>Results</p> <p>Six patients suffered from ACL graft retear (9.4%). Mean duration between primary ACL reconstruction and incidence of retears was 11.7 months. However, there were no other postoperative graft ruptures after 24 months. Primary injury and retear mechanisms varied by patient. At six months after the primary ACL reconstruction surgery, mean quadriceps and hamstring strengths were 81% and 87%, respectively, indicating favorable recovery of muscle strength. However, preoperative quadriceps and hamstring strength in the retear group were 65% and 71%, respectively. In particular, preoperative quadriceps strength in the retear group demonstrated a lower value than that in the uninjured group (<it>P </it>< 0.05).</p> <p>Conclusions</p> <p>We observed a high incidence of ACL graft retears in competitive female basketball players, as previously reported. Considering the timing of graft retear occurrences, an early return to playing basketball should be avoided following ACL reconstruction. Closer attention should be paid to player preoperative condition, as well as muscle strength and postoperative status.</p

    Repeated freeze–thaw cycles reduce the survival rate of osteocytes in bone-tendon constructs without affecting the mechanical properties of tendons

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    Frozen bone-patellar tendon bone allografts are useful in anterior cruciate ligament reconstruction as the freezing procedure kills tissue cells, thereby reducing immunogenicity of the grafts. However, a small portion of cells in human femoral heads treated by standard bone-bank freezing procedures survive, thus limiting the effectiveness of allografts. Here, we characterized the survival rates and mechanisms of cells isolated from rat bones and tendons that were subjected to freeze–thaw treatments, and evaluated the influence of these treatments on the mechanical properties of tendons. After a single freeze–thaw cycle, most cells isolated from frozen bone appeared morphologically as osteocytes and expressed both osteoblast- and osteocyte-related genes. Transmission electron microscopic observation of frozen cells using freeze-substitution revealed that a small number of osteocytes maintained large nuclei with intact double membranes, indicating that these osteocytes in bone matrix were resistant to ice crystal formation. We found that tendon cells were completely killed by a single freeze–thaw cycle, whereas bone cells exhibited a relatively high survival rate, although survival was significantly reduced after three freeze–thaw cycles. In patella tendons, the ultimate stress, Young’s modulus, and strain at failure showed no significant differences between untreated tendons and those subjected to five freeze–thaw cycles. In conclusion, we identified that cells surviving after freeze–thaw treatment of rat bones were predominantly osteocytes. We propose that repeated freeze–thaw cycles could be applied for processing bone-tendon constructs prior to grafting as the treatment did not affect the mechanical property of tendons and drastically reduced surviving osteocytes, thereby potentially decreasing allograft immunogenecity

    Potent Immune Modulation by MEDI6383, an Engineered Human OX40 Ligand IgG4P Fc Fusion Protein.

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    Ligation of OX40 (CD134, TNFRSF4) on activated T cells by its natural ligand (OX40L, CD252, TNFSF4) enhances cellular survival, proliferation, and effector functions such as cytokine release and cellular cytotoxicity. We engineered a recombinant human OX40L IgG4P Fc fusion protein termed MEDI6383 that assembles into a hexameric structure and exerts potent agonist activity following engagement of OX40. MEDI6383 displayed solution-phase agonist activity that was enhanced when the fusion protein was clustered by Fc gamma receptors (FcγRs) on the surface of adjacent cells. The resulting costimulation of OX40 on T cells induced NFκB promoter activity in OX40-expressing T cells and induced Th1-type cytokine production, proliferation, and resistance to regulatory T cell (Treg)-mediated suppression. MEDI6383 enhanced the cytolytic activity of tumor-reactive T cells and reduced tumor growth in the context of an alloreactive human T cell:tumor cell admix model in immunocompromised mice. Consistent with the role of OX40 costimulation in the expansion of memory T cells, MEDI6383 administered to healthy nonhuman primates elicited peripheral blood CD4 and CD8 central and effector memory T-cell proliferation as well as B-cell proliferation. Together, these results suggest that OX40 agonism has the potential to enhance antitumor immunity in human malignancies

    Development of a food frequency questionnaire to estimate habitual dietary intake in Japanese children

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    <p>Abstract</p> <p>Background</p> <p>Food frequency questionnaires (FFQ) are used for epidemiological studies. Because of the wide variations in dietary habits within different populations, a FFQ must be developed to suit the specific group. To date, no FFQ has been developed for Japanese children. In this study, we developed a FFQ to assess the regular dietary intake of Japanese children. The FFQ included questions regarding both individual food items and mixed dishes.</p> <p>Methods</p> <p>Children (3-11 years of age, n = 621) were recruited as subjects. Their parents or guardians completed a weighed dietary record (WDR) for each subject in one day. We defined FOOD to be not only as a single food item but also as a mixed dish. The dieticians conceptually grouped similar FOODs as FOOD types. We used a contribution analysis and a multiple regression analysis to select FOOD types.</p> <p>Results</p> <p>We obtained a total of 586 children's dietary data (297 boys and 289 girls). In addition, we obtained 1,043 FOODs. Dieticians grouped into similar FOODs, yielding 275 FOOD types. A total of 115 FOOD types were chosen using a contribution analysis and a multiple regression analysis, then we excluded overlapping items. FOOD types that were eaten by fewer than 15 subjects were excluded; 74 FOOD types remained. We also added liver-based dishes that provided a high amount of retinol. A total of 75 FOOD types were finally determined for the FFQ. The frequency response formats were classified into four type categories: seven, eight, nine and eleven, according to the general intake frequency of each FOOD type. Information on portion size was obtained from the photographs of each listed FOOD type in real scale size, which was the average amount of the children's portion sizes.</p> <p>Conclusions</p> <p>Using both a contribution analysis and a multiple regression analysis, we developed a 75-food item questionnaire from the study involving 586 children. The next step will involve the verification of FFQ reproducibility and validity.</p

    Prescreening based on the presence of CT-scan abnormalities and biomarkers (KL-6 and SP-D) may reduce severe radiation pneumonitis after stereotactic radiotherapy

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    <p>Abstract</p> <p>Purpose</p> <p>To determine the risk factors of severe radiation pneumonitis (RP) after stereotactic body radiation therapy (SBRT) for primary or secondary lung tumors.</p> <p>Materials and methods</p> <p>From January 2003 to March 2009, SBRT was performed on 117 patients (32 patients before 2005 and 85 patients after 2006) with lung tumors (primary = 74 patients and metastatic/recurrent = 43 patients) in our institution. In the current study, the results on cases with severe RP (grades 4-5) were evaluated. Serum Krebs von den Lungen-6 (KL-6) and serum Surfactant protein-D (SP-D) were used to predict the incidence of RP. A shadow of interstitial pneumonitis (IP) on the CT image before performing SBRT was also used as an indicator for RP. Since 2006, patients have been prescreened for biological markers (KL-6 & SP-D) as well as checking for an IP-shadow in CT.</p> <p>Results</p> <p>Grades 4-5 RP was observed in nine patients (7.7%) after SBRT and seven of these cases (6.0%) were grade 5 in our institution. A correlation was found between the incidence of RP and higher serum KL-6 & SP-D levels. IP-shadow in patient's CT was also found to correlate well with the severe RP. Severe RP was reduced from 18.8% before 2005 to 3.5% after 2006 (<it>p </it>= 0.042). There was no correlation between the dose volume histogram parameters and these severe RP patients.</p> <p>Conclusion</p> <p>Patients presenting with an IP shadow in the CT and a high value of the serum KL-6 & SP-D before SBRT treatment developed severe radiation pneumonitis at a high rate. The reduction of RP incidence in patients treated after 2006 may have been attributed to prescreening of the patients. Therefore, pre-screening before SBRT for an IP shadow in CT and serum KL-6 & SP-D is recommended in the management and treatment of patients with primary or secondary lung tumors.</p
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