3,704 research outputs found

    The Effects of Prenatal Cannabis Exposure on the Basolateral Amygdala

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    Clinical and preclinical studies indicate prenatal cannabis exposure (PCE) pathologically affects fetal brain development and may increase vulnerability to neuropsychiatric disorders, including schizophrenia and mood/anxiety disorders. In review research from our lab suggests that fetal exposure to Δ9-THC sex-selectively impairs mesocorticolimbic (MCL) circuit function. However, there is a distinct lack of focus on PCE models on the BLA. The BLA plays a central role within the MCL where it directly interacts with the VTA, PFC and HIPP. Importantly, our model exhibits significant VTA hyperdopaminergic activity, and sex-specific alterations to PFC/HIPP glutamate firing, alongside region- and sex-specific changes in dopamine (DA), glutamate/GABA molecular markers. These result in outward pathological behavioural manifestations with males exhibiting enhanced anxiety and both sexes exhibiting cognitive deficits. Given the role of the BLA, it is necessary to mechanistically explore the effect of PCE on the BLA. The present study characterized the interconnected pathophenotype of the BLA-MCL circuit using behavioural, electrophysiological, molecular, and mechanistic assays. Pregnant Wistar rats were assigned to VEH (n=10 dams; n=4 progeny/sex/dam) or 3mg/kg THC (daily, i.p.; n=10 dams; n=4 progeny/sex/dam) from gestational day (GD) 7 to GD22. A subset of progeny (n=8/treatment/sex) were sacrificed on PD21 for molecular assays of the NAc and BLA. Between PD70-85, a subset of progeny (n=20/treatment/sex) were assessed for anxiety, depression, prepulse inhibition, and contextual fear. Between PD90-120, in vivo electrophysiology was used to assess VTA DA-ergic neurons, glutamate, and GABA neurons in the posterior/anterior BLA, and NAc GABA neurons. On PD120, remaining offspring were sacrificed and NAc and BLA punchouts were obtained for molecular assays. A behaviour naïve subset (n=10/sex/treatment) received intra-BLA cannulations for mechanistic assays between PD90-120. In line with previous results, males exhibit a significant anxiogenic phenotype; however, males also exhibited significantly less freezing, suggesting a deficit in contextual fear learning, consistent with significant increases in GAD67 expression; males also exhibit increases in D1R and GABAARα1. Female progeny did not exhibit any outward pathology but did exhibit significantly greater expression of vGLUT2, GABAARα1, and GABAARɣ2. Disturbances in dopaminergic, glutamatergic, and GABAergic electrophysiological activity were also observed in the male progeny within the VTA-BLA-NAc circuit, but not in the female progeny. These suggest that the anxiogenic deficits observed in males are likely contingent on BLA disruptions, while the female progeny is protected from BLA-dependant etiology. Mechanistic assays are currently ongoing

    Comment: Further sufficient conditions for an inverse relationship between productivity and employment

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    Extant empirical studies document that productivity gains due to technological progress often lead to reductions in employment. This paper rationalizes the stated empirical finding within the context of the theory of the competitive firm under price uncertainty. We show that technological progress affects employment adversely if the firm's coefficient of relative risk aversion is no less than unity and its production technology exhibits non-decreasing returns to scale. On the other hand, technological progress unambiguously increases output if the firm's preference has non-increasing absolute risk aversion. © 1999 Board of Trustees of the University of Illinois. All rights reserved.postprin

    On the Origin of Mass and Angular Momentum of Stellar Objects

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    Externalities of Urban Renewal: A Real Option Perspective

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    If carefully planned, urban renewal may play an important role in regenerating a decaying neighborhood and mitigating the negative externality generated by dilapidated buildings in densely populated areas. Despite its potential benefits, in urban areas dominated by high-rise developments, urban renewal has an unintended negative impact on nearby properties since it reduces their redevelopment option values. In this study, we develop a number of hypotheses on how an urban renewal project, once made known to the public, affects neighborhood housing prices and test them with data in Hong Kong. Our empirical findings suggest that the degree of positive externalities brought by urban renewal depends on the scale of an urban renewal project, as well as the amount of commercial areas included in the project. Most importantly, through examining changes in the age coefficient, we found that an urban renewal project reduces the value of nearby buildings beyond the boundaries of the project. The negative effect was stronger for older buildings and for those buildings located closer to the project’s boundaries. These unintended consequences of urban renewal have not been analyzed or tested in previous studies.postprin

    Automatic systole-diastole classification of mitral valve complex from RT-3D echocardiography based on multiresolution processing

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    Poster Session: UltrasoundMitral valve repair is one of the most prevalent operations for various mitral valve conditions. Echocardiography, being famous for its low-cost, non-invasiveness and speediness, is the dominant imaging modality used for carrying out mitral valve condition analysis in both pre-operative and intra-operative examinations. In order to perform analysis on different phases of a cardiac cycle, it is necessary to first classify the echocardiograhic data into volumes corresponding to the systole and diastole phases. This often requires tedious manual work. This paper presents a fully-automatic method for systole-diastole classification of real-time three-dimensional transesophageal echocardiography (RT-3D-TEE) data. The proposed method first resamples the data with radial cutting planes, segments the mitral valve by thresholding, and removes noise by median filtering. Classification is then carried out based on the number of identified mitral valve regions. A multiresolution processing scheme is proposed to further improve the classification accuracy by aggregating classification results obtained from different image resolution scales. The proposed method was evaluated against the classification results produced by a cardiologist. Experimental results show that the proposed method, without the use of computationally intensive algorithms or the use of any training database, can achieve a classification accuracy of 91.04%.published_or_final_versio

    Evaluation of a Structured Volunteering Programme as an Intervention for Enhancing Resilience Level of Parents of People with Learning Disabilities

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    The East Asian Archives of Psychiatry can be viewed at: http://easap.asia/journal_file/EASAP-Suppl-2012.pdfPoster session D: Child and Adolescent Mental Health ProblemsConference Theme: Mental Health for AllBackground: Stresses have consistently been found to be higher in parents of people with learning disabilities (LD). However, some parents are able to be more resilient and better adapted in the face of these challenges. It is known that volunteering experience is able to increase one’s resilient protector factors. This study was an initial attempt to evaluate how a structured volunteering programme enhances the resilience level of parents of people with LD. The programme lasted for 6 months and the parent volunteers paid home visits regularly to elderly who were living alone and were invited to attend the debriefing sessions after every visit. Objectives: The researchers examined the effectiveness of the structured volunteering programme in enhancing the resilience level of parents of people with LD, and to identify the specific resilience domains that are correlating with the programme. Methods: A pretest-posttest design was adopted, with the intervention of a 6-month structured volunteering programme. The researchers developed a 24-item scale which extracted from the Resilience Scale – Chinese Version (Chen, 2007; the original scale was developed by Friborg et al. in 2006) and the Purpose in Life Test – Chinese Version (Song, 1992; the original test was developed by Crumbaugh & Maholic in 1964). The scale achieved good reliability (α = 0.935). Data on 36 participants’ measures of 4 resilience domains, namely, self-competence, social skills, social resources, and meaning of life, were analysed. Results: Statistically significant positive changes in the resilience domains of social resources (p = 0.05) and meaning of life (p = 0.04) were found, the domain of social skills also showed positive change. Conclusion: The results suggest the effectiveness of the structured volunteering programme for parents of LD in resilience enhancement. The programme design would be discussed.published_or_final_versio

    香港公立醫院中外陰切開術的應用情況

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    OBJECTIVE. To review the use of episiotomy during vaginal delivery in Hong Kong public hospitals. DESIGN. Prospective observational survey. SETTING. Public hospitals, Hong Kong. PARTICIPANTS. Women who underwent normal vaginal delivery of a singleton foetus with cephalic presentation. MAIN OUTCOME MEASURES. Number of women having an episiotomy, severe-degree (third- or fourth-degree) tear, other types of tear, blood loss at delivery, postpartum haemorrhage, need for blood transfusion, puerperal pyrexia, wound infection, gaping wound that required suture removal, and drainage or resuturing of a perineal wound. RESULTS. Between 1 January and 31 March 2003, there were 6222 singleton spontaneous normal vaginal deliveries in the public hospitals of Hong Kong. Of the 6167 women in whom the status of the perineum was known, episiotomy was performed in 5274 (85.5%). Primiparous women were more likely to undergo episiotomy at delivery than multiparous women (97.9% vs 71.4%). Women with episiotomy had significantly less perineal tearing of any kind than those without. The occurrence of any type of perineal tear and severe-degree (third- or fourth-degree) tear was significantly lower in primiparous women who had an episiotomy than those without (P<0.05). Women with episiotomy had increased mean blood loss at delivery but other complications were not significantly increased. CONCLUSIONS. In Hong Kong, episiotomy is routinely performed during normal vaginal delivery. It is associated with a significantly lower overall rate of perineal tearing. This study was observational, nonetheless the occurrence of other complications was likely to increase when episiotomy was performed. Firm evidence from several randomised controlled studies shows that routine episiotomy is unjustified and possibly harmful. Routine episiotomy should not be promoted in Hong Kong without further randomised controlled study.published_or_final_versio

    The value of the provision of a balcony in apartments in Hong Kong

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    In Hong Kong, a balcony is often perceived as a “green” provision in modern residential buildings. However, how the market values the benefits of balconies is seldom studied due to the difficulty in separating such benefits from other associated effects such as view enjoyment and security concerns. This paper attempts to study the implicit value of a balcony, the green effects of balconies on the prices of residential properties, and the effect of security concerns on balconies situated on lower floors. A sample of transactions in a private housing estate in Hong Kong has been studied. The sample contains apartments with and without balconies. A balcony is found to have a positive effect on the value of a property irrespective of the quality of the view. The negative effects of air and noise pollution on property prices are also found to be highly significant. Although security concerns are found on the low stories of a building, the provision of a balcony does not aggravate the hazard. Finally, the log-linearity assumption in the empirical price model is relaxed by applying the Box-Cox transformation to the continuous variables.published_or_final_versio

    The significance and performance of infrastructure in China

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    Building a model for encouraging help-seeking for depression: a qualitative study in a Chinese society

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    BACKGROUND:Clinical depression has been increasingly prevalent in international health statistics but people are often found to be reluctant to seek help when they encounter depression. However, there is no general theory to explain how personal, social and cultural factors affect an individual's help-seeking intention, nor to guide the design of preventive programmes for such intention once needed.METHODS:Drawing on the theory of planned behavior, we deployed the illness narrative approach and interviewed 18 participants in Hong Kong.RESULTS:With the diverse results we gathered from the interviews, a behavioral model was built to conceptualize the interplays of various factors in shaping one's help-seeking intention and behavior for depression. Participants appeared to have a limited view of treatment options and had diverse views of the symptoms of depression, both of which profoundly affected their motivation to seek help.CONCLUSIONS:The role of family and friends and a holistic approach to mental health education were found to be particularly important for encouraging help-seeking behavior in future campaigns concerning depression.published_or_final_versio
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