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The effects of alcohol expectancies on drinking behaviour in peer groups: observations in a naturalistic setting
No full textABSTRACT Aims To study the functionality of alcohol expectancies in predicting drinking behaviour in existing peer groups of young adults in a 'naturalistic' setting. Design and setting Young adults were invited to join an experiment with their peer group in a bar annex laboratory. During a 'break' of 50 minutes in this experiment, their activities, social behaviour and drinking behaviour were observed with digital video and audio equipment. Participants Twenty-eight peer groups were involved in this study. A peer group consisted of seven to nine people, with relationships ranging from intimate relations and close friendships to being acquaintances. A total of 238 participants were involved. Measurements Information of the drinking behaviour from observations and questionnaire data on alcohol expectancies provide the opportunity to look at how and which expectancies are related to actual drinking patterns. Multiple regression and multi-level analyses were applied. Findings Expectancies on the positive and arousing effects of alcohol consumption were related to alcohol consumption in a naturalistic, social drinking situation, in addition to group effects of drinking. Expectancies on the negative and sedative effects of drinking, however, were not related to drinking. Conclusions The findings indicate that among young adults observed in a peer group and naturalistic drinking setting, positive expectancies about the effects of alcohol and expectancies about the effects of alcohol on arousal are related positively to drinking level
Abnormal Ras signaling in Costello syndrome (CS) negatively regulates enamel formation
No full textRASopathies are syndromes caused by gain-of-function mutations in the Ras signaling pathway. One of these conditions, Costello syndrome (CS), is typically caused by an activating de novo germline mutation in HRAS and is characterized by a wide range of cardiac, musculoskeletal, dermatological and developmental abnormalities. We report that a majority of individuals with CS have hypo-mineralization of enamel, the outer covering of teeth, and that similar defects are present in a CS mouse model. Comprehensive analysis of the mouse model revealed that ameloblasts, the cells that generate enamel, lacked polarity, and the ameloblast progenitor cells were hyperproliferative. Ras signals through two main effector cascades, the mitogen-activated protein kinase (MAPK) and phosphatidylinositol-3-kinase (PI3K) pathways. To determine through which pathway Ras affects enamel formation, inhibitors targeting either PI3K or MEK 1 and 2 (MEK 1/2), kinases in the MAPK pathway, were utilized. MEK1/2 inhibition rescued the hypo-mineralized enamel, normalized the ameloblast polarity defect and restored normal progenitor cell proliferation. In contrast, PI3K inhibition only corrected the progenitor cell proliferation phenotype. We demonstrate for the first time the central role of Ras signaling in enamel formation in CS individuals and present the mouse incisor as a model system to dissect the roles of the Ras effector pathways in vivo
Dextrocardia with Situs Inversus, Atrio-ventricular and Ventricular-arterial Concordance and a Left Posterior Aorta in a Preterm Twin Neonate
No full textAbstract In dextrocardia, the main base-apex cardiac axis is directed to the right side of the chest. The majority of dextrocardia is associated with situs solitus and either normally related or L-transposed great vessels. Dextrocardia with situs inversus is rare and presents in different forms depending on the atrio-ventricular (AV) and ventricular-aterial (VA) relationship. We report a rare case of dextrocardia with situs inversus, AV and VA concordance, a left posterior aorta and a right aortic arch in a preterm twin male infant. Introduction The main cardiac axis (base to apex) determines the orientation of the heart in the chest. In dextrocardia, the axis points to the right instead of the left Case Report A 32-week twin a male infant, weighing 1810 grams, was born to a 32 year-old G5P1 mother. This was a di-di twin pregnancy with IUGR in twin B. The pregnancy was complicated by in-vitro fertilization, gestational diabetes, hypothyroidism "on levothyroxine", preeclampsia "on magnesium sulfate", and preterm labor. The mother underwent C-section due to worsening pre-eclampsia. Both twins were given basic neonatal care. APGARs cores were 8 and 9 at 1 and 5 minutes, respectively. They had stable vital signs with oxygen saturation of 97% on room air. While twin B had a normal examination, twin A was incidentally noted to have heart sounds on the right side of the chest. No murmurs were appreciated. A chest X-ray An echocardiogram showed a mirror image dextrocardia with inversion of both atria and ventricle
A new electrode wear compensation method for improving performance in 3D micro EDM milling A new electrode wear compensation method for improving performance in 3D micro EDM milling
No full textAbstract As one of the non-traditional manufacturing processes, micro electrical discharge machining (EDM) has been widely applied for manufacturing precise and complex microstructures. However, a number of issues remain to be studied before micro EDM can become a reliable processing method. Efforts to get higher machining quality and to improve efficiency have been carried out. The electrode wear compensation method is one of the key factors in micro EDM milling. This paper proposes a new electrode wear compensation method, the combination of the linear compensation method (LCM) and the uniform wear method (UWM), called the CLU method. This approach combines LCM, UWM and the theoretical model. Experimental results indicate that machining performance such as material removal rate, electrode wear ratio and surface roughness using the proposed method has been improved compared to that by the uniform wear method
LONG-RUN PERSISTENCE IN RESERVOIR INFLOWS: EMPIRICAL MODE DECOMPOSITION IN SYDNEY AND MELBOURNE
Get PDFABSTRACT This paper quantifies long-run hydrological persistence in reservoir inflows to two regions: Melbourne and Sydney. We use a relatively new approach in hydrology, Empirical Mode Decomposition (EMD). Our three key results are summarised below: (1) For Melbourne and Sydney inflows, 57-66% of total variance was accounted for by periodicities <10 years; 20-21% of total variance was attributable to periodicities >10 years; and 14-22
Weak Minimal Area in Entanglement Entropy
Get PDFWe revisit the minimal area condition of Ryu-Takayanagi in the holographic calculation of the entanglement entropy, in particular, the Legendre test and the Jacobi test. The necessary condition for the weak minimality is checked via Legendre test and its sufficient nature via Jacobi test. We show for AdS black hole with a strip type entangling region that it is this minimality condition that makes the hypersurface unable to cross the horizon, which is in agreement with that studied earlier by Engelhardt et al. and Hubeny using a different approach. Moreover, demanding the weak minimality condition on the entanglement entropy functional with the higher derivative term puts a constraint on the Gauss-Bonnet coupling; that is, there should be an upper bound on the value of the coupling, < ( − 3)/4( − 1)
What works to improve the quality of student learning in developing countries?
No full textAbstract: We conducted a systematic review to identify policy interventions that improve education quality and student learning in developing countries. Relying on a theory of change typology, we highlight three main drivers of change of education quality: first, supply-side capability interventions that operate through the provision of physical and human resources, and learning materials; second, policies that through incentives seek to change both teachers, household and student behaviour and intertemporal preferences; and third, bottom-up and topdown participatory and community management interventions, which operate through decentralization reforms and knowledge diffusion and increased community participation in the management of education systems. Overall, our findings suggest that policy interventions are more effective in improving student performance and learning when two or more drivers of change are combined. Supply-side interventions are more effective when they are complemented with community participation and/or incentives. Thus, idiosyncrasies, social norms and intertemporal preferences need to be factored in when designing education policies in developing countries