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To test the hypotheses that multigenerational predation risk favors clones with longer postero-lateral spines and a larger body, and that fitness consequences of selection depend on both tested fitness variables and selection intensity, we expose replicate Brachionus dorcas populations in low (LK) and high (HK) concentrations of Asplanchna kairomones. Over 60 days (23 asexual generations) of selection, LK-selected populations showed the highest equilibrium population densities, and median mictic ratios and postero-lateral spine lengths, and HK-selected populations showed the lowest equilibrium population densities, the highest mictic ratios, and the longest postero-lateral spines, among all the control and treatment populations. In the absence of Asplanchna kairomones, and compared with populations with the control selection history, populations with an LK selection history showed increased growth rates/intrinsic rates of population increase and net reproductive rates, but decreased mictic ratios, indicating three fitness gains and a fitness cost; and those with an HK selection history showed increased life expectancy at hatching and mictic ratios, but decreased growth rates, indicating two fitness gains and a fitness cost. Asplanchna kairomones might increase the heritability of higher equilibrium densities or mictic ratios, and longer postero-lateral spines, and thus enable the prey to survive predation. [ABSTRACT FROM AUTHOR]

To test the hypothesis that non-consumptive predation pressures favor genotypes that have higher equilibrium densities or mictic ratios, we expose replicate populations of the rotifer Brachionus angularis to low (LK) and high (HK) concentrations of predator Asplanchna kairomones. Over 75 days (25 asexual generations) of selection, LK-treated populations have higher equilibrium densities and lower mictic ratios than the control populations. The opposite occurs for HK-treated populations. These results suggest that compared with the control, LK and HK select for genotypes with higher equilibrium densities and mictic ratios, respectively. Common garden bioassays reveal that in the absence of Asplanchna kairomones, populations with an LK selection history have a higher average intrinsic rate of population increase, and those with an HK selection history have a higher average mictic ratio than those with the control selection history, which suggest that adaptations to LK and HK increase average intrinsic rate of population increase and mictic ratio of prey populations, respectively. Increased intrinsic rate of population increase and mictic ratio can serve as strategies of offsetting mortality from predation and escaping the predator, and thus enable prey to survive low and high predation pressures, respectively. [ABSTRACT FROM AUTHOR]

Background: Autistic people are vulnerable to developing mental health problems due to their difficulties in managing social situations and interpersonal relationships. The popular online social media (OSM) can be a potential solution to these concerns for their social lives as it allows non-face-to-face social interactions, however it remained unclear how this group is using these online platforms. This study explored their experiences of using online social media, and their perceived benefits and risks associated with this use. Method: Qualitative data was collected through in-depth face to face interviews. We recruited 13 autistic young adults who were with normal intelligence from two community centers in Hong Kong. Interviews were conducted in a semi-structured format by experienced clinical psychologist and social workers. Results: Four themes were identified from the data, namely: (1) Paradox of using OSM to supplement social needs; (2) Unpleasant social interactions in the online environment; (3) Restricted and repetitive pattern of interest leading to troubles in OSM use, and; (4) Privacy and personal safety issues. The results suggested that while OSM could be a useful tool for our participants to connect with existing friends and to meet new ones, their limitations, such as difficulties in understanding languages and social interaction as well as restricted patterns of interests could potentially put them at risk, including interpersonal conflicts, cyber-bullying, financial scams, as well as unwanted sexual experiences. These experiences not only paradoxically increased their sense of loneliness and their distance from others, but also resulted in a negative impact on their mood and functioning. Conclusion: This qualitative study provided some insights into the OSM use among autistic young adults. OSM could be a useful tool to overcome potential limitations in social interactions, but at the same time it could potentially bring detrimental consequences. In order to maximize the benefits of online social networking, there is a need for timely guidance and support to use OSM among autists, and for psychoeducation to promote awareness, and enable adequate skills and behaviors attainment associated with safe OSM use. [ABSTRACT FROM AUTHOR]

Background: Electronic media use (EMU) becomes one of the most common activities in adolescents. The present study investigated the deleterious influence of excessive EMU and EMU before bedtime on social, emotional, and behavioral difficulties (SEBD) in adolescents. The role of sleep and circadian problems in mediating the association of EMU with SEBD was examined. Methods: A cross-sectional survey study was conducted with 3,455 adolescents (55.7% female, mean age = 14.8 ± 1.57 years, 36.6% monthly family income < HK$15,000) between December 2011 and March 2012 in Hong Kong. The associations of EMU with sleep and circadian problems and SEBD were analyzed usingmultiple binary logistic regression and path analysis. Sleep problems were measured by the Insomnia Severity Index and the reduced Horne and Östberg Morningness and Eveningness Questionnaire. Circadian problems were calculated based on established formulas. SEBD was measured using the Strengths and Difficulties Questionnaire. Participants' mental health status was assessed by the General Health Questionnaire. Results: A longer duration of EMU, excessive EMU (daily duration ≥ 2 h), and bedtime EMU (an hour before bedtime) were associated with the risk of sleep and circadian problems, poor mental health, and SEBD (p < 0.05). Insomnia, eveningness, social jetlag, and sleep deprivation were found to mediate the associations of EMU (including bedtime EMU of computers, electronic game consoles, phones, and televisions, together with excessive EMU of computers for leisure purposes and phones) with mental health and SEBD. Conclusions: The findings suggest the need for setting up guidelines and advocacy for education for appropriate EMU and intervention for the associated sleep and circadian problems to ameliorate EMU-related mental and behavioral health problems in adolescents. [ABSTRACT FROM AUTHOR]

Accurately measuring the costs and social benefits of environmental programs may have significant public sector policy implications. When considering environmental programs, governments may choose to conduct landfill clean-ups to improve urban living environments and health. However, these programs may generate substantial costs, and it is not clear whether their social benefits can recover these costs. Since the 1990s, the Hong Kong government has restored 13 closed landfills. This study seeks to quantify the short-term social benefits of this landfill clean-up program by measuring its impact on the housing market. Using the difference-in-differences method, we find that housing prices near landfill sites increase about 2.2%, on average, within two years after landfill restoration. However, housing prices show no further change after the restored landfill sites are redeveloped into urban parks and other facilities. We argue that removal of the stigma effect is likely the main channel for housing price hikes. Through a back-of-the-envelope estimation, we find that the social benefits from housing value appreciation can sufficiently recover the program costs. [ABSTRACT FROM AUTHOR]

Hepatitis E virus (HEV) genotype 4 (HEV-4) is an emerging cause of acute hepatitis in China. Less is known about the clinical characteristics and natural history of HEV-4 than HEV genotype 3 infections in immunocompromised patients. We report transmission of HEV-4 from a deceased organ donor to 5 transplant recipients. The donor had been viremic but HEV IgM and IgG seronegative, and liver function test results were within reference ranges. After a mean of 52 days after transplantation, hepatitis developed in all 5 recipients; in the liver graft recipient, disease was severe and with progressive portal hypertension. Despite reduced immunosuppression, all HEV-4 infections progressed to persistent hepatitis. Four patients received ribavirin and showed evidence of response after 2 months. This study highlights the role of organ donation in HEV transmission, provides additional data on the natural history of HEV-4 infection, and points out differences between genotype 3 and 4 infections in immunocompromised patients. [ABSTRACT FROM AUTHOR]

The PM2.5 (particulate matters with aerodynamic diameter ≤2.5µm) distribution with large scale and high resolution is required for the protection of atmospheric environment and epidemiology studies. In this study, an improved geographically and temporally weighted regression (IGTWR) model incorporating seasonal characteristics is proposed to estimate the PM2.5 concentrations over Hong Kong. The IGTWR model is established using MODerate resolution Imaging Spectroradiometer (MODIS) aerosol optical depth (AOD) derived by SARA (simplified aerosol retrieval algorithm), meteorological data and land use data. A comparison among ordinary least squares (OLS), geographically weighted regression (GWR), geographically and temporally weighted regression (GTWR) and the proposed IGTWR indicate that the IGTWR model has the best prediction performance for PM2.5 concentrations with highest R2 (0.752) and smallest RMSE (9.651µg/m3). The annual mean PM2.5 distribution at 500 m resolution over Hong Kong from 2012 to 2014 is derived using IGTWR, demonstrating its potential of satellite-based PM2.5 monitoring. [ABSTRACT FROM AUTHOR]

Purpose: In this study, we aimed to evaluate the efficacy of sentence-combining (SC) and narrative-based (NAR) intervention approaches to syntax intervention using a randomized-controlled-trial design. Method: Fifty-two Cantonese-speaking, school-age children with language impairment were assigned randomly to either the SC or the NAR treatment arm. Seven children did not receive treatment as assigned. Intervention in both arms targeted the same complex syntactical structures. The SC group focused on sentence combination training, whereas the NAR group made use of narratives in which the target structures were embedded. Pretest and posttest performances measured using a standardized language assessment were subjected to analyses of covariance mixed-effect-model analyses of variance. Results: Children in both treatment arms demonstrated significant growth after 4 months of intervention. The main effect between treatment arms and time was not significant after controlling the pretest performance, suggesting that both treatment approaches showed similar effects. The main effect of time was significant. Conclusions: This study provided evidence to support language intervention in the school years in Cantonese-speaking children. However, neither approach was shown to be more efficacious than the other. Future researchers could examine the effects of a longer treatment period and include functional outcome measures. [ABSTRACT FROM AUTHOR]

OBJECTIVES: To evaluate the effectiveness of a multilevel and multimodal school-based education program. METHODS: A cluster randomized controlled trial with 14 secondary schools in Hong Kong and a total of 3713 students (intervention: 1545 vs control: 2168; 40.2% boys; mean age ± SD: 14.72 ± 1.53 years) were included in the final analysis. The intervention included a town hall seminar, small class workshops, a slogan competition, a brochure, and an educational Web site. Their parents and teachers were offered sleep education seminars. The control schools did not receive any sleep program. Data were collected before and 5 weeks after the intervention. RESULTS: The students in the intervention group had significantly improved sleep knowledge compared with the control group (mean difference: 3.64 [95% confidence interval (CI): 3.21 to 4.07]; Cohen's d = 0.51) as measured by using a sleep knowledge questionnaire. Weekday sleep duration was reduced in both groups, and the significant difference in weekday sleep duration was lost in the intention-to-treat analysis (mean difference: 0:01 [95% CI: -0:00 to 0: 04]). In addition, the intervention group had a lower incidence of consuming caffeine-containing energy drinks (adjusted odds ratio: 0.46 [95% CI: 0.22 to 0.99]) and had better behavioral (mean difference: -0.56 [95% CI: -1.02 to -0.10]; Cohen's d = 0.13) and mental health (mean difference: -0.30 [95% CI: -0.15 to -0.46]; Cohen's d = 0.11) outcomes. CONCLUSIONS: A school-based sleep education program was effective in enhancing sleep knowledge and improving behavioral and mental health, but it had no significant impact on sleep duration or pattern among adolescents. [ABSTRACT FROM AUTHOR]