1,185 research outputs found
Reduction of Coxiella burnetii prevalence by vaccination of goats and sheep, the Netherlands
Recently, the number of human Q fever cases in the Netherlands increased dramatically. In response to this increase, dairy goats and dairy sheep were vaccinated against Coxiella burnetii. All pregnant dairy goats and dairy sheep in herds positive for Q fever were culled. We identified the effect of vaccination on bacterial shedding by small ruminants. On the day of culling, samples of uterine fluid, vaginal mucus, and milk were obtained from 957 pregnant animals in 13 herds. Prevalence and bacterial load were reduced in vaccinated animals compared with unvaccinated animals. These effects were most pronounced in animals during their first pregnancy. Results indicate that vaccination may reduce bacterial load in the environment and human exposure to C. burnetii
Growth control of GaAs nanowires using pulsed laser deposition with arsenic over pressure
Using pulsed laser ablation with arsenic over pressure, the growth conditions
for GaAs nanowires have been systematically investigated and optimized. Arsenic
over pressure with As molecules was introduced to the system by thermal
decomposition of polycrystalline GaAs to control the stoichiometry and shape of
the nanowires during growth. GaAs nanowires exhibit a variety of geometries
under varying arsenic over pressure, which can be understood by different
growth processes via vapor-liquid-solid mechanism. Single-crystal GaAs
nanowires with uniform diameter, lengths over 20 m, and thin surface oxide
layer were obtained and can potentially be used for further electronic
characterization
Costs of compliance with EU regulations and competitiveness of the EU dairy sector
The introduction of cross-compliance mechanism in the European Union with its 2003 CAPreform might affect the costs of production and thus competitiveness of the EU. Little evidence is available to asses the costs of compliance with regulations and it implication for trade. In this study a farm level competitiveness analysis of the impacts of the Nitrate Directive and the Identification & registration Directive focuses on the dairy sector in Germany, France, Italy, Netherlands and UK (within EU), and the US and New Zealand (outside EU). The findings from this study are integrated into a trade analysis which assesses the impact of compliance costs on competitiveness of the various trading nations in global trade. Representative farm studies were used as a basis for the cost increase calculations. Best-estimates of compliance are used from the existing literature and expert judgements. The negative impact of these measures (for nitrates, and animal identification and registration) on EU imports and exports are less than 3 percent. If a smaller increase in compliance takes place, these already relatively small trade impacts will be further diminished. When the standards for nitrate pollution taken by the US and New Zealand are taken into account along with full compliance assumption in all countries analysed, this would only slightly improve the EU exports. The trade impacts obtained when no changes are assumed to happen in key competitor countries can thus be argued as providing the upper bound of the likely trade impacts
Psychosocial and biological risk factors of anxiety disorders in adolescents:a TRAILS report
Anxiety disorders are a common problem in adolescent mental health. Previous studies have investigated only a limited number of risk factors for the development of anxiety disorders concurrently. By investigating multiple factors simultaneously, a more complete understanding of the etiology of anxiety disorders can be reached. Therefore, we assessed preadolescent socio-demographic, familial, psychosocial, and biological factors and their association with the onset of anxiety disorders in adolescence. This study was conducted among 1584 Dutch participants of the TRacking Adolescents' Individual Lives Survey (TRAILS). Potential risk factors were assessed at baseline (age 10-12), and included socio-demographic (sex, socioeconomic status), familial (parental anxiety and depression), psychosocial (childhood adversity, temperament), and biological (body mass index, heart rate, blood pressure, cortisol) variables. Anxiety disorders were assessed at about age 19 years through the Composite International Diagnostic Interview (CIDI). Univariate and multivariate logistic regression analyses were performed with onset of anxiety disorder as a dependent variable and the above-mentioned putative risk factors as predictors. Of the total sample, 25.7% had a lifetime diagnosis of anxiety disorder at age 19 years. Anxiety disorders were twice as prevalent in girls as in boys. Multivariate logistic regression analysis showed that being female (OR = 2.38, p <.01), parental depression and anxiety (OR = 1.34, p = .04), temperamental frustration (OR = 1.31, p = .02) and low effortful control (OR = 0.76, p = .01) independently predicted anxiety disorders. We found no associations between biological factors and anxiety disorder. After exclusion of adolescents with an onset of anxiety disorder before age 12 years, being female was the only significant predictor of anxiety disorder. Being female was the strongest predictor for the onset of anxiety disorder. Psychological and parental psychopathology factors increased the risk of diagnosis of anxiety, but to a lesser extent. Biological factors (heart rate, blood pressure, cortisol, and BMI), at least as measured in the present study, are unlikely to be useful tools for anxiety prevention and intervention strategies
Molecular monitoring of microbial diversity in expanded granular sludge bed (EGSB) reactors treating oleic acid
A molecular approach was used to evaluate the microbial diversity of bacteria and archaea in two expanded granular sludge bed
(EGSB) reactors fed with increasing oleic acid loading rates up to 8 kg of chemical oxygen demand (COD) mˉ³ dayˉ¹ as the sole carbon source. One of the reactors was inoculated with granular sludge (RI) and the other with suspended sludge (RII). During operation, the
sludge in both reactors was segregated in two layers: a bottom settled one and a top floating one. The composition of the bacterial
community, based on 16S rDNA sequence diversity, was affected most during the oleate loading process in the two reactors. The archaeal
consortium remained rather stable over operation in RI, whereas in RII the relative abundance of Methanosaeta-like organisms became
gradually weaker, starting in the bottom layer. In the range of oleate loads evaluated, 6 kg of COD mˉ³ dayˉ¹ was found as the
maximum value that could be applied to the system. A further increase to 8 kg of oleate-COD mˉ³ dayˉ¹ induced a maximal shift on the
microbial structure of the sludges. At this time point, methanogenic acetoclastic activity was not detected and only very low methanogenic
activity on H2/CO2 was exhibited by the sludges.Fundação para a Ciência e a Tecnologia (FCT) - PRAXIS XXI/BD/20326/99.Fundação Calouste Gulbenkian (FCG)
Efficient single-photon emission from electrically driven InP quantum dots epitaxially grown on Si(001)
The heteroepitaxy of III-V semiconductors on silicon is a promising approach
for making silicon a photonic platform for on-chip optical interconnects and
quantum optical applications. Monolithic integration of both material systems
is a long-time challenge, since different material properties lead to high
defect densities in the epitaxial layers. In recent years, nanostructures
however have shown to be suitable for successfully realising light emitters on
silicon, taking advantage of their geometry. Facet edges and sidewalls can
minimise or eliminate the formation of dislocations, and due to the reduced
contact area, nanostructures are little affected by dislocation networks. Here
we demonstrate the potential of indium phosphide quantum dots as efficient
light emitters on CMOS-compatible silicon substrates, with luminescence
characteristics comparable to mature devices realised on III-V substrates. For
the first time, electrically driven single-photon emission on silicon is
presented, meeting the wavelength range of silicon avalanche photo diodes'
highest detection efficiency
Social Anxiety and Empathy:A Systematic Review and Meta-analysis
OBJECTIVE: This systematic review and meta-analysis aimed to clarify the association between social anxiety and affective (AE) and cognitive empathy (CE). METHODS: 1442 studies from PsycINFO, Medline, and EMBASE (inception-January 2020) were systematically reviewed. Included studies (N = 48) either predicted variance in empathy using social anxiety scores or compared empathy scores between socially anxious individuals and a control group. RESULTS: Social anxiety and AE were statistically significantly positively associated, k = 14, r = .103 (95%CI [.003, .203]), z = 2.03, p = .043. Sex (QM (2) = 18.79, p < .0001), and type of measures (QM (1 = 7.34, p = .007) moderated the association. Correlations were significant for male samples (rmale = .316, (95%CI [.200, .432])) and studies using self-report measures (rself-report = .162 (95%CI [.070, .254])). Overall, social anxiety and CE were not significantly associated, k = 52, r =-.021 (95%CI [-.075, .034]), z= -0.74, p = .459. Sample type moderated the association (QM (1) = 5.03, p < .0001). For clinical samples the association was negative (rclinical= -.112, (95%CI [-.201, -.017]). CONCLUSION: There was evidence for a positive association between social anxiety and AE, but future studies are needed to verify the moderating roles of sex and type of measure. Besides, low CE might only hold for patients with SAD
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