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While studies suggest that nutritional supplementation may reduce aggressive behavior in children, few have examined their effects on specific forms of aggression. This study tests the primary hypothesis that omega-3 (ω-3), both alone and in conjunction with social skills training, will have particular post-treatment efficacy for reducing childhood reactive aggression relative to baseline.
In this randomized, double-blind, stratified, placebo-controlled, factorial trial, a clinical sample of 282 children with externalizing behavior aged 7–16 years was randomized into ω-3 only, social skills only, ω-3 + social skills, and placebo control groups. Treatment duration was 6 months. The primary outcome measure was reactive aggression collected at 0, 3, 6, 9, and 12 months, with antisocial behavior as a secondary outcome.
Children in the ω-3-only group showed a short-term reduction (at 3 and 6 months) in self-report reactive aggression, and also a short-term reduction in overall antisocial behavior. Sensitivity analyses and a robustness check replicated significant interaction effects. Effect sizes (d) were small, ranging from 0.17 to 0.31.
Findings provide some initial support for the efficacy of ω-3 in reducing reactive aggression over and above standard care (medication and parent training), but yield only preliminary and limited support for the efficacy of ω-3 in reducing overall externalizing behavior in children. Future studies could test further whether ω-3 shows promise in reducing more reactive, impulsive forms of aggression.
Mentorship is perceived to be an important component of residency education. However, evidence of the impact of mentorship on professional development in Emergency Medicine (EM) is lacking.
Online survey distributed to attending physician members of the Canadian Association of Emergency Physicians (CAEP), using a modified Dillman method. Survey contained questions about mentorship during residency training, and perceptions of the impact of mentorship on career development.
The response rate was 23.5% (309/1314). 63.6% reported having at least one mentor during residency. The proportion of participants with a formal mentorship component during residency was higher among those with mentors (44.5%) compared to those without any formal mentorship component during residency (8.0%, p<0.001). The most common topics discussed with mentors were career planning and work-life balance. The least common topics included research and finances. While many participants consulted their mentor regarding their first job (56.5%), fewer consulted their mentor regarding subspecialty training (45.1%) and research (41.1%). 71.8% chose to work in a similar centre as their mentor, but few completed the same subspecialty (24.8%), or performed similar research (30.4%). 94.1% stated that mentorship was important to success during residency. Participants in a formal mentorship program did not rate their experience of mentorship higher than those without a formal program.
Among academic EM physicians with an interest in mentorship, mentorship during EM residency may have a greater association with location of practice than academic scholarship or subspecialty choice. Formal mentorship programs increase the likelihood of obtaining a mentor, but do not appear to improve reported mentorship experiences.
Mothers who have experienced childhood maltreatment are more likely to have children also exposed to maltreatment, a phenomenon known as intergenerational transmission. Factors in the perinatal period may contribute uniquely to this transmission, but timing effects have not been ascertained. Using structural equation modeling with 1,016 mothers and their 2,032 children in the Environmental Risk Longitudinal Twin Study, we tested the mediating role of postpartum depression between maternal childhood maltreatment and a cascade of negative child outcomes, specifically child exposure to maltreatment, internalizing symptoms, and externalizing symptoms: (a) adjusting for later maternal depression, (b) comparing across sex differences, and (c) examining the relative role of maltreatment subtypes. Mothers who had been maltreated as children, especially those who had experienced emotional or sexual abuse, were at increased risk for postpartum depression. In turn, postpartum depression predicted children’s exposure to maltreatment, followed by emotional and behavioral problems. Indirect effects from maternal childhood maltreatment to child outcomes were robust across child sex and supported significant mediation through postpartum depression; however, this appeared to be carried by mothers’ depression beyond the postpartum period. Identifying and treating postpartum depression, and preventing its recurrence, may help interrupt the intergenerational transmission of maltreatment and its sequelae.
We report on the astrometric registration of VLBI images of the SiO and H2O masers in OH 231.8+4.2, the iconic Proto-Planetary Nebula also known as the Calabash nebula, using the KVN and Source/Frequency Phase Referencing. This, for the first time, robustly confirms the alignment of the SiO masers, close to the AGB star, which drives the bi-lobe structure with the water masers in the out-flow.
Thermal plasma wind tunnels with power of 0.4 MW and 2.4 MW have been constructed at Chonbuk National University (CBNU) in Korea. This facility is capable of producing a heat flux greater than 10 MW/m2, a level that is relevant for testing thermal protection materials that are used for re-entry vehicles in space transportation. A segmented arc plasma torch was adopted as a plasma source; this was designed to have high thermal efficiency and long life, and to produce a supersonic plasma flow with enthalpy greater than 10 MJ/kg. We investigated the characteristics of the supersonic plasma flow using intrusive and non-intrusive diagnostic systems. Ablation characteristics of potential thermal protection materials such as carbon/carbon composites and graphite were investigated with the plasma wind tunnel. Cracks and pores in the materials accelerated the erosion. For carbon/carbon composites, the pores grew and the cracks which occurred at the interfaces between the carbon fibres and the matrix propagated, while for the graphite, the erosion started at the pores and peeled off the surface.
Introduction: Sepsis protocols call for the acquisition of blood cultures in septic emergency department (ED) patients.However, the criteria for blood cultures are vague, they are costly, only positive 8-12% of the time, with up to half of these being false positives. The objective of this study was to establish if positive blood cultures could be excluded in low-risk sepsis patients with levels of CRP below 20 ml/L. Methods: This was a multicenter prospective cohort study of 765 ED patients at St Paul’s and Mount St Joseph’s hospitals in Vancouver with sepsis (2 or more SIRS criteria and infection) and none of: immuncompromised, injection drug use, indwelling vascular device or septic shock (SBP<90 mmhg). Consecutive patients with sepsis had CRP and blood cultures obtained at the same time.OUTCOMES. True positive blood cultures, false positive blood cultures, positive blood cultures that changed patient management. True and false positive blood cultures were based on Infectious Disease Society of America Guidelines, and change in management was defined as change in type or length of antibiotic therapy and was blindly adjudicated by a medical microbiologist. Results: 765 ED patients with sepsis met inclusion criteria. Mean age was 48.3 years and 57% were male. Blood cultures were positive in 99/765 (12.9%) subjects, of which 19 were false positive (19.2%). CRP was >20 mg/L in 595/765 (77.8%) of patients. Of 170 subjects with a CRP<20 mg/L, 3 had a positive blood culture (1.8%; 95% CI 0.1%- 5%). Management was not changed in any patient with a positive blood culture and CRP level<20 mg/L. Of 19 subjects with a false positive blood culture, CRP was <20 mg/L for 6 (31.6%). Conclusion: In this cohort of low-risk sepsis patients, based on a CRP of <20 mg/L, acquisition of blood cultures could be safely avoided in 22.2% of patients, at significant savings to the health care system.
Almost nothing is known about the potential negative effects of Internet-based psychological treatments for depression. This study aims at investigating deterioration and its moderators within randomized trials on Internet-based guided self-help for adult depression, using an individual patient data meta-analyses (IPDMA) approach.
Studies were identified through systematic searches (PubMed, PsycINFO, EMBASE, Cochrane Library). Deterioration in participants was defined as a significant symptom increase according to the reliable change index (i.e. 7.68 points in the CES-D; 7.63 points in the BDI). Two-step IPDMA procedures, with a random-effects model were used to pool data.
A total of 18 studies (21 comparisons, 2079 participants) contributed data to the analysis. The risk for a reliable deterioration from baseline to post-treatment was significantly lower in the intervention v. control conditions (3.36 v. 7.60; relative risk 0.47, 95% confidence interval 0.29–0.75). Education moderated effects on deterioration, with patients with low education displaying a higher risk for deterioration than patients with higher education. Deterioration rates for patients with low education did not differ statistically significantly between intervention and control groups. The benefit–risk ratio for patients with low education indicated that 9.38 patients achieve a treatment response for each patient experiencing a symptom deterioration.
Internet-based guided self-help is associated with a mean reduced risk for a symptom deterioration compared to controls. Treatment and symptom progress of patients with low education should be closely monitored, as some patients might face an increased risk for symptom deterioration. Future studies should examine predictors of deterioration in patients with low education.
The Darwin region in northern Australia has experienced rapid population growth in recent years, and with it, an increased incidence of melioidosis. Previous studies in Darwin have associated the environmental presence of Burkholderia pseudomallei, the causative agent of melioidosis, with anthropogenic land usage and proximity to animals. In our study, we estimated the occurrence of B. pseudomallei and Burkholderia spp. relatives in faecal matter of wildlife, livestock and domestic animals in the Darwin region. A total of 357 faecal samples were collected and bacteria isolated through culture and direct DNA extraction after enrichment in selective media. Identification of B. pseudomallei, B. ubonensis, and other Burkholderia spp. was carried out using TTS1, Bu550, and recA BUR3–BUR4 quantitative PCR assays, respectively. B. pseudomallei was detected in seven faecal samples from wallabies and a chicken. B. cepacia complex spp. and Pandoraea spp. were cultured from wallaby faecal samples, and B. cenocepacia and B. cepacia were also isolated from livestock animals. Various bacteria isolated in this study represent opportunistic human pathogens, raising the possibility that faecal shedding contributes to the expanding geographical distribution of not just B. pseudomallei but other Burkholderiaceae that can cause human disease.
Specific roles of individual CDPKs vary, but in general they mediate essential biological functions necessary for parasite survival. A comparative analysis of the structure-activity relationships (SAR) of Neospora caninum, Eimeria tenella and Babesia bovis calcium-dependent protein kinases (CDPKs) together with those of Plasmodium falciparum, Cryptosporidium parvum and Toxoplasma gondii was performed by screening against 333 bumped kinase inhibitors (BKIs). Structural modelling and experimental data revealed that residues other than the gatekeeper influence compound–protein interactions resulting in distinct sensitivity profiles. We subsequently defined potential amino-acid structural influences within the ATP-binding cavity for each orthologue necessary for consideration in the development of broad-spectrum apicomplexan CDPK inhibitors. Although the BKI library was developed for specific inhibition of glycine gatekeeper CDPKs combined with low inhibition of threonine gatekeeper human SRC kinase, some library compounds exhibit activity against serine- or threonine-containing CDPKs. Divergent BKI sensitivity of CDPK homologues could be explained on the basis of differences in the size and orientation of the hydrophobic pocket and specific variation at other amino-acid positions within the ATP-binding cavity. In particular, BbCDPK4 and PfCDPK1 are sensitive to a larger fraction of compounds than EtCDPK1 despite the presence of a threonine gatekeeper in all three CDPKs.
In February 2012, an outbreak of gastroenteritis was reported in school A; a successive outbreak was reported at school B. A retrospective cohort study conducted in school A showed that seasoned green seaweed with radishes (relative risk 7·9, 95% confidence interval 1·1–56·2) was significantly associated with illness. Similarly, a case-control study of students at school B showed that cases were 5·1 (95% confidence interval 1·1–24·8) times more likely to have eaten seasoned green seaweed with pears. Multiple norovirus genotypes were detected in samples from students in schools A and B. Norovirus GII.6 isolated from schools A and B were phylogenetically indistinguishable. Green seaweed was supplied by company X, and norovirus GII.4 was isolated from samples of green seaweed. Green seaweed was assumed to be linked to these outbreaks. To our knowledge, this is the first reported norovirus outbreak associated with green seaweed.
Imprinting control regions (ICRs) play a fundamental role in establishing and maintaining the non-random monoallelic expression of certain genes, via common regulatory elements such as non-coding RNAs and differentially methylated regions (DMRs) of DNA. We recently surveyed DNA methylation levels within four ICRs (H19-ICR, IGF2-DMR, KvDMR, and NESPAS-ICR) in whole-blood genomic DNA from 128 monozygotic (MZ) and 128 dizygotic (DZ) human twin pairs. Our analyses revealed high individual variation and intra-domain covariation in methylation levels across CpGs and emphasized the interaction between epigenetic variation and the underlying genetic sequence in a parent-of-origin fashion. Here, we extend our analysis to conduct two genome-wide screenings of single nucleotide polymorphisms (SNPs) underlying either intra-domain covariation or parent-of-origin-dependent association with methylation status at individual CpG sites located within ICRs. Although genome-wide significance was not surpassed due to sample size limitations, the most significantly associated SNPs found through multiple-trait genome-wide association (MQFAM) included the previously described rs10732516, which is located in the vicinity of the H19-ICR. Similarly, we identified an association between rs965808 and methylation status within the NESPAS-ICR. This SNP is positioned within an intronic region of the overlapping genes GNAS and GNAS-AS1, which are imprinted genes regulated by the NESPAS-ICR. Sixteen other SNPs located in regions apart from the analyzed regions displayed suggestive association with intra-domain methylation. Additionally, we identified 13 SNPs displaying parent-of-origin association with individual methylation sites through family-based association testing. In this exploratory study, we show the value and feasibility of using alternative GWAS approaches in the study of the interaction between epigenetic state and genetic sequence within imprinting regulatory domains. Despite the relatively small sample size, we identified a number of SNPs displaying suggestive association either in a domain-wide or in a parent-of-origin fashion. Nevertheless, these associations will require future experimental validation or replication in larger and independent samples.
Extra-planar gas in spiral galaxies can originate from disk-halo cycling driven by star formation in the disk or from infalling gas clouds. Studying the kinematics of halo gas can provide evidence for which scenario is more plausible. Edge-on galaxies provide a direct view of the extra-planar gas. We measure gas velocities from Hα emission as a function of height above the galactic disk for NGC 4244, which has a low star formation rate, and NGC 891, which has a high star formation rate. Using a multi-slit setup on the ARC 3.5 m telescope, we are able to measure velocities along 16 slits simultaneously. We compare our preliminary results to studies of HI velocities in these galaxies.
GaN films have been grown atop Si-terminated 3C-SiC intermediate layer on Si(111) substrates using low pressure metalorganic chemical vapor deposition (LP-MOCVD). The SiC intermediate layer was grown by chemical vapor deposition (CVD) using tetramethylsilane (TMS) as the single source precursor. The Si terminated SiC surface was obtained by immediately flow of SiH4 gas after growth of SiC film. LP-MOCVD growth of GaN on 3C-SiC/Si(111) was carried out with trimethylgallium (TMG) and NH3. Single crystalline hexagonal GaN layers can be grown on Si terminated SiC intermediate layer using an AlN or GaN buffer layer. Compared with GaN layers grown using a GaN buffer layer, the crystal qualities of GaN films with AlN buffer layers are extremely improved. The GaN films were characterized by x-ray diffraction (XRD), photoluminescence (PL) and scanning electron microscopy (SEM). Full width at half maximum (FWHM) of double crystal x-ray diffraction (DCXD) rocking curve for GaN (0002) on 3C-SiC/Si(111) was 890 arcsec. PL near band edge emission peak position and FWHM at room temperature are 3.38 eV and 79.35 meV, respectively.
The conditions for the equilibrium shape of a second-phase particle nucleating either at a planar interface or at a spherically curved interface are reviewed under the assumption that the interfacial structure of the nucleation site has a torque of an appropriate strength. The results are then incorporated into the modified Gibbs-Wulff construction in order to demonstrate a graphical representation of both the equilibrium shape and the free energy barrier for heterogeneous nucleation.
The passive film stability of several Fe-based amorphous metal formulations have been found to be comparable to that of high-performance Ni-based alloys, and superior to that of stainless steels, based on electrochemical measurements of the passive film breakdown potential and general corrosion rates. Chromium (Cr), molybdenum (Mo) and tungsten (W) provide corrosion resistance; boron (B) enables glass formation; and rare earths such as yttrium (Y) lower critical cooling rate (CCR). The high boron content of this particular amorphous metal also makes it an effective neutron absorber, and suitable for criticality control applications, as discussed in companion publications. Corrosion data for SAM2X5 (Fe49.7Cr17.7Mn1.9Mo7.4W1.6B15.2C3.8Si2.4) is discussed here.