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The current study advanced research on the link between community violence exposure and aggression by comparing the effects of violence exposure on different functions of aggression and by testing four potential (i.e., callous–unemotional traits, consideration of others, impulse control, and anxiety) mediators of this relationship. Analyses were conducted in an ethnically/racially diverse sample of 1,216 male first-time juvenile offenders (M = 15.30 years, SD = 1.29). Our results indicated that violence exposure had direct effects on both proactive and reactive aggression 18 months later. The predictive link of violence exposure to proactive aggression was no longer significant after controlling for proactive aggression at baseline and the overlap with reactive aggression. In contrast, violence exposure predicted later reactive aggression even after controlling for baseline reactive aggression and the overlap with proactive aggression. Mediation analyses of the association between violence exposure and reactive aggression indicated indirect effects through all potential mediators, but the strongest indirect effect was through impulse control. The findings help to advance knowledge on the consequences of community violence exposure on justice-involved youth.
To investigate discrepancies in dose calculation algorithms used for lung stereotactic body radiotherapy (SBRT) plans.
Methods and materials
In total, 30 patients lung SBRT treatment plans, initially generated using BrainLab Pencil Beam (BL_PB) algorithm for 10 Gy×5 Fractions to the planning target volume (PTV) were included in the study. These plans were recalculated using BrainLab Monte Carlo (BL_MC), Eclipse AAA (EC_AAA), Eclipse Acuros XB (EC_AXB) and ADAC Pinnacle CCC (AP_CCC) algorithms. Dose volume histograms of PTV were used to calculate dosimetric and radiobiological quality indices, and equivalent dose to 2 Gy per fraction using linear-quadratic-linear model. The BL_MC algorithm is considered gold standard tool to compare PTV parameters and quality indices to investigate dose calculation discrepancies of abovementioned plans.
BL_PB overestimates doses that may be due to inability of the algorithm to properly account for electron scattering and transport in inhomogeneous medium. Compared with BL_MCNO plans, the EC_AAA and EC_AXB yield lower homogeneity indices and overestimate the dose in the penumbra region, whereas AP_CCC plans were comparable for small PTV (≈8 cc) and had significant difference for large PTV.
BL_PB algorithm overestimates PTV doses than BL_MC calculated doses. The EC_AAA, EC_AXB and AP_CCC algorithms calculate doses within acceptable limits of radiotherapy dose delivery recommendations.
This study evaluated dosimetric parameters for cervical high-dose-rate (HDR) brachytherapy treatment using varying dose prescription methods.
This study includes 125 tandem-based cervical HDR brachytherapy treatment plans of 25 patients who received HDR brachytherapy. Delineation of high-risk clinical target volumes (HR-CTVs) and organ at risk were done on original computed tomographic images. The dose prescription point was defined as per International Commission in Radiation Units and Measurements Report Number 38 (ICRU-38), also redefined using American Brachytherapy Society (ABS) 2011 criteria. The coverage index (V100) for each HR-CTV was calculated using dose volume histogram parameters. A plot between HR-CTV and V100 was plotted using the best-fit linear regression line (least-square fit analysis).
Mean prescribed dose to ICRU-38 Point A was 590·47±28·65 cGy, and to ABS Point A was 593·35±30·42 cGy. There was no statistically significant difference between planned ICRU-38 and calculated ABS Point A doses (p=0·23). The plot between HR-CTV and V100 is well defined by the best-fit linear regression line with a correlation coefficient of 0·9519.
For cervical HDR brachytherapy, dose prescription to an arbitrarily defined point (e.g., Point A) does not provide consistent coverage of HR-CTV. The difference in coverage between two dose prescription approaches increases with increasing CTV. Our ongoing work evaluates the dosimetric consequences of volumetric dose prescription approaches for these patients.
This study aimed to assess and compare the epidemiology of faecal carriage of extended spectrum β-lactamase-producing enterobacteria (ESBL-E) in Hepatology departments of two hospitals specializing in liver diseases, Theodor Bilharz Research Institute (TBRI) in Cairo (Egypt) and Beaujon Hospital (Bj) in Clichy (France). CTX-M groups were identified by PCR, and TEM and SHV derivatives with the check-point system. Phylogenetic groups of E. coli were determined by multiplex PCR, and clone ST131 by PCR of gene pabB. Prevalence of ESBL-E was 77·6% (45/58) in TBRI and 6·5% (13/199) in Bj (P < 10−7). Previous hospitalization was more common (P = 0·003) in Bj patients (93%) than in TBRI patients (45%) suggesting high prevalence of ESBL-E in the Egyptian community. The presence of E. coli B2 ST131 among ESBL-E faecal E. coli in Egypt confirms its pervasiveness in the community and raises concern regarding this highly virulent and resistant clone.
EMU is a wide-field radio continuum survey planned for the new Australian Square Kilometre Array Pathfinder (ASKAP) telescope. The primary goal of EMU is to make a deep (rms ∼ 10 μJy/beam) radio continuum survey of the entire Southern sky at 1.3 GHz, extending as far North as +30° declination, with a resolution of 10 arcsec. EMU is expected to detect and catalogue about 70 million galaxies, including typical star-forming galaxies up to z ∼ 1, powerful starbursts to even greater redshifts, and active galactic nuclei to the edge of the visible Universe. It will undoubtedly discover new classes of object. This paper defines the science goals and parameters of the survey, and describes the development of techniques necessary to maximise the science return from EMU.
Independent outbreaks of dengue virus (DENV) infection and sporadic cases of chikungunya virus (CHIKV) have been recorded in the metropolitan city of Delhi on several occasions in the past. However, during a recent 2010 arboviral outbreak in Delhi many cases turned negative for DENV. This prompted us to use duplex reverse transcriptase–polymerase chain reaction (D-RT–PCR) to establish the aetiology of dengue/chikungunya through sequencing of CprM and E1 genes of dengue and chikungunya viruses. Interestingly, for the first time, both DENV and CHIKV co-circulated simultaneously and in equally dominant proportion during the post-monsoon period of 2010. DENV-1 genotype III and the East Central South African genotype of CHIKV were associated with post-monsoon spread of these viruses.
Epitaxial SiGe/Si heterostructures have been formed by wet oxidation from amorphous SixGe1−x, films deposited on Si(100). This process does not occur by solid phase epitaxy(SPE) due to the presence of a contamination layer between the film and the substrate. The model which has been suggested involves both the diffusion of Si to the forming oxide and enhanced Ge diffusion below this contamination layer. The oxide which is formed in this process consists of four separate layers, with the middle two containing both SiO2 and GeO2. In addition, initial epitaxial formation appears to occur in random regions, probably where the diffusing Si breaks through the contamination layer. Epitaxial submicron “donut” regions on Si(100) can also be formed by this method, and the mechanism will be discussed.
The chemical vapor deposition of Al-Cu thin films on Si, SiO2, and TiN substrates was examined in a vertical low pressure cold wall reactor using trimethylamine alane (TMAA1) at 20 C as the Al source. The Cu sources bis-(hexafluoroacetylacetonato)copper(H)(CuHFA), (cyclopentadienyl)copper(I) triethylphosphine (CpCuPEt3), and (hexafluoroacetylacetonato)copper(I) trimethylphosphine (HfaCuPMe3), were compared. The Cu content of the films was controlled up to“5 wt% by simply varying the temperature of the Cu source. Codeposited Al-Cu films with excellent conductivity, purity, and adhesion properties were obtained with all Cu sources. Optimal film smoothness was achieved at∼350 C. The compounds differed in the ease of control over the %Cu in the films. CuHFA exhibited a massive parasitic reaction which made control very difficult. The Cu(I) complexes showed very minor parasitic reactions. Analysis of films with high Cu content by SEM-EDS showed clear segregation of Cu and Al, consistent with the low solubility of Cu in Al. Films with >2% Cu appeared homogeneous on a μm scale by both SEM-EDS and SIMS depth profiling. TEM of film cross sections revealed a polycrystalline Al film with small (20–100 Å) Cu-rich particles dispersed throughout the Al grains. These particles exhibited bright field-dark field contrast characteristic of crystalline material.
Explosive recrystallization of amorphous layers, induced by scanned electron or CW Ar+ laser beams, has been investigated in arsenic implanted (100) specimens. We have studied the microstructural changes using plan-view and crosssection electron microscopy to obtain the mechanism of explosive recrystallization phenomenon. The confinement of heat in the amorphous layers during laser irradiation and the nature of amorphous silicon determine the modes of explosive recrystallization. We indicate that, depending upon the degree of undercooling, two distinct modes of liquid-phase recrystallization are observed: one occurring at a velocity of, ∼2 ms−1 and the other at ∼10ms−1. Explosively recrystallized grains contain <110> and <110> as surface normal and growth direction respectively. We present a model for unseeded crystallization to explain the <110> texture observed in diamond cubic lattices.
We have used embedded piezoresistive microcantilever (EPM) sensors in the detection of hydrogen cyanide gas. EPM sensors are small, MEMS-based devices consisting of a tiny piezoresistive microcantilever partially embedded into a “sensing material” designed to respond volumetrically when exposed to the desired analyte. These EPM sensors may be very small, operate on simple and inexpensive support electronics, are highly resistant to movement or shock, may be operated by hardwire connection or wirelessly in large numbers, and are capable of detecting many different analytes. In this study, we have used EPM sensors to detect hydrogen cyanide gas. Preliminary results indicate that the EPM sensors provide a fast response (less than 5 seconds) to levels of HCN that may be lethal to humans.
We studied the correlation of in and ex situ stress to microstructures during Al-induced crystallization for structures of Al on top (AOT) and Al on bottom (AOB) of amorphous Si (a-Si) on 3000 Å SiO2 coated on Si wafers and found that a-Si deposited on PECVD SiO2 and Al increases the stress compressively, and Al deposited on PECVD SiO2 and on a-Si decreases the stress tensilely. In addition, the stress of AOB structures is in general less than that of AOT structures. Correlation of stress to microstructures indicated that the difference in microstructures between AOT and AOB results from the nature of the layer structures themselves. By using modified Stoney's equation, the lower stress of AOB structures than AOT could be explained with existence of oxide between a-Si and Al for both AOT and AOB structures.
Embedded piezoresistive microcantilever (EPM) sensors provide a tiny, low-cost, and robust platform for the detection of chemical or biological analytes. New sensing applications become potentially available as the design or synthesis of new sensing materials for EPM instruments are studies. In this study, we report on the detection of hydrogen fluoride gas (HF) in air, and in a medical application, the measurement of human hydration levels. Two sensing materials characterize these applications, thiolated gold nanoparticles in a keratin matrix (HF), and a crosslinked PVA-based hydrogel in the hydration application.
While the cause of Parkinson's disease (PD) remains unknown, evidence suggests certain environmental factors, such as well water drinking, herbicides, pesticides exposure and neurotoxins, may trigger the chain of oxidative reactions culminating in the death of dopaminergic neurons in substantia nigra to cause Parkinsonism. To investigate the possible impact of environmental risk factors for idiopathic PD, a case-control study was performed in the Eastern India.
During the period from January 1st, 2006 and December 10th, 2009, 175 PD patients (140 men, 35 women) and 350 non-Parkinson age-sex matched controls were included in the study. Subjects were given a structured neurological examination and completed an administered questionnaire which elicited detailed information on demographic data, pesticides, herbicides family history, occupation, dietary and smoking habits.
The multivariate analysis revealed that family history of PD, pesticide exposure, exposure to toxins other than pesticides and herbicides, rural living and previous history of depression were associated with increased risk of PD, whereas, smoking appeared to be a protective factor. Well water drinking for at least five years, though a significant risk factor on univariate analysis (OR=4.5, 95% CI=2.1-9.9), could not be proved significant in multivariate analysis. Head trauma, vegetarian dietary habit, occupation involving physical exertion and exposure to domestic pets were not as significant risk factors.
Results of our study support the hypothesis of multifactorial etiology of PD with environmental factors acting on a genetically susceptible host.
Genomic variability within the sequences of VP1/2A junction among polioviruses from across the globe has revealed the existence of several endemic genotypes and their epidemiological inter-relationships; but such data on Indian isolates are scanty. The present work was intended to ascertain the persistence and transmission pattern of different genotypes of wild type 1 polioviruses circulating in India. Forty-eight wild type 1 poliovirus isolates obtained from different parts of India during 1996–8 were subjected to RT–PCR and nucleotide sequencing using M13 tailed primers. A 293 base pair region was amplified and sequenced for genetic variation study. Considering the 15% divergence of the sequences from Sabin 1, the isolates from six different states of India confirmed a single dominant genotype 4. Phylogenetic analysis revealed the circulation and active inter-state transmission of many genetically distinct strains of wild poliovirus type 1 belonging to genotype 4. This warrants the need for insisting on more efficient surveillance mechanisms so as to assess the impact of an extensive pulse polio immunization programme in India.
A. S. Alexandrov, IRC in Superconductivity, University of Cambridge, Madingley Road, Cambridge CB3 OHE, UK,
V. V. Kabanov, Laboratoire des Propriétés Mécaniques et Thermodynamiques des Matériaux, CNRS Université Paris-Nord, 93430 Villetaneuse, France,
D. K. Ray, Laboratoire des Propriétés Mécaniques et Thermodynamiques des Matériaux, CNRS Université Paris-Nord, 93430 Villetaneuse, France
The observed characteristics of mid infrared (MIR) spectra in doped semiconductors are discussed. These characteristics were explained by Reik and coworkers on the basis of hopping motion of small polarons from a localized site to a neighbouring localized site. The success and limitations of this model are pointed out. Emin, on the other hand, showed the importance of large polarons for the conductivity. The recently observed features of MIR spectra in high-Tc cuprates are then summarized. The low-frequency peak in many cuprates with frequency 0.1−0.2 eV has been ascribed by many investigators to polaronic origin. We have undertaken in the present work numerical studies of polaronic conductivity in the two-site and four-site cluster model by diagonalization of the dynamical matrix. Broadening of the phonon spectra due to damping has been taken into account by considering a small but finite phonon lifetime. For intermediate and strong coupling, a number of peaks in the optical conductivity appear due to bound states with different numbers of phonons. We have also studied the importance of Hubbard U by calculating the optical conductivity as a function of U with two electrons in a two-site model. The experimental results of MIR spectra for the cuprates can be better understood on the basis of the present calculations.
It was Landau who first introduced the idea of polarons for explaining the F centres in NaCl as due to self-trapping of electrons . Polarons are the quasiparticles formed by the accompanying self-consistent polarization field and are generated due to the dynamical electron–phonon interaction. As a consequence there is extra scattering of the charge carriers, phonon energies are renormalized and the charge carriers are heavy .
Complete development of Ancylostoma ceylanicum (Hamster strain) is reported for the first time in mice. A patent infection (viz. ova in faeces) could be established only under the influence of hydrocortisone acetate. Cultures made from the faeces containing eggs produced viable larvae which were infective to mice.
The federal government has supported and continues to support or share in the support, financially and technically, of several regional pest management programs. Implicit in continued federal support is the concept that the benefits of the program to society exceed the governmental portion of the costs. As these programs are evaluated and consideration is given to discontinuing federal support, improved estimates of program benefits, or costs of discontinuing, are needed.
The objective of this study was to identify and quantify the expected effects in terms of agricultural output, insecticide use, and production costs of discontinuing a regional boll weevil suppression program on the Texas High Plains. Results of this study are useful to governmental decision makers, local producers, environmentalists and economists.
The route of migration and development of Ancylostoma ceylanicum, when given orally, has been described for the first time in hamsters. A predominant feature of the migration is the absence of any lung journey. This is unlike A. caninum, A. duodenale and A, brazilicnse when larvae are similarly given to an abnormal host. The larvae of A. ceylanicum apparently had no submucosal migration
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