2,172 research outputs found
Relationships of homophobic bullying during childhood and adolescence with problematic internet and smartphone use in early adulthood among sexual minority men in Taiwan
Background: Mental health disparity in sexual minorities is a crucial clinical and public health issue worldwide. A total of 500 homosexual or bisexual men aged between 20 and 25 years participated in this study. Objectives: The aims of the study were to examine the relationships of victimization of traditional and cyber homophobic bullying during childhood and adolescence with problematic internet and smartphone use and activities during early adulthood among sexual minority men in Taiwan. Methods: The seveirities of problematic internet and smartphone use and activities in early adulthood were compared between victims and non-victims of bullying. The severities of problematic internet and smartphone use were also compared among the groups of various types of bullying as well as among the groups of various persistence durations of being bullied. Results: Victims of traditional and cyber homophobic bullying had more severe problematic internet and smartphone use than non-victims. Victims of multi-type bullying had more severe problematic internet use than victims of single-type bullying. Prolonged victimization was significantly associated with problematic internet and smartphone use. Discussion: Victimization of traditional and cyber homophobic bullying during childhood and adolescence predicts problematic internet and smartphone use during early adulthood among sexual minority men
Calibration of second-order correlation functions for non-stationary sources with a multi-start multi-stop time-to-digital converter
A novel high-throughput second-order-correlation measurement system is
developed which records and makes use of all the arrival times of photons
detected at both start and stop detectors. This system is suitable particularly
for a light source having a high photon flux and a long coherence time since it
is more efficient than conventional methods by an amount equal to the product
of the count rate and the correlation time of the light source. We have used
this system in carefully investigating the dead time effects of detectors and
photon counters on the second-order correlation function in the two-detector
configuration. For a non-stationary light source, distortion of original signal
was observed at high photon flux. A systematic way of calibrating the
second-order correlation function has been devised by introducing a concept of
an effective dead time of the entire measurement system.Comment: 7 pages, 6 figure
Crystallization of Adenylylsulfate Reductase from Desulfovibrio gigas: A Strategy Based on Controlled Protein Oligomerization
Adenylylsulfate reductase (adenosine 5′-phosphosulfate reductase, APS reductase or APSR, E.C.1.8.99.2) catalyzes the conversion of APS to sulfite in dissimilatory sulfate reduction. APSR was isolated and purified directly from massive anaerobically grown Desulfovibrio gigas, a strict anaerobe, for structure and function investigation. Oligomerization of APSR to form dimers–α_2β_2, tetramers–α_4β_4, hexamers–α_6β_6, and larger oligomers was observed during purification of the protein. Dynamic light scattering and ultracentrifugation revealed that the addition of adenosine monophosphate (AMP) or adenosine 5′-phosphosulfate (APS) disrupts the oligomerization, indicating that AMP or APS binding to the APSR dissociates the inactive hexamers into functional dimers. Treatment of APSR with β-mercaptoethanol decreased the enzyme size from a hexamer to a dimer, probably by disrupting the disulfide Cys156—Cys162 toward the C-terminus of the β-subunit. Alignment of the APSR sequences from D. gigas and A. fulgidus revealed the largest differences in this region of the β-subunit, with the D. gigas APSR containing 16 additional amino acids with the Cys156—Cys162 disulfide. Studies in a pH gradient showed that the diameter of the APSR decreased progressively with acidic pH. To crystallize the APSR for structure determination, we optimized conditions to generate a homogeneous and stable form of APSR by combining dynamic light scattering, ultracentrifugation, and electron paramagnetic resonance methods to analyze the various oligomeric states of the enzyme in varied environments
Observation of sub-Poisson photon statistics in the cavity-QED microlaser
We have measured the second-order correlation function of the cavity-QED
microlaser output and observed a transition from photon bunching to
antibunching with increasing average number of intracavity atoms. The observed
correlation times and the transition from super- to sub-Poisson photon
statistics can be well described by gain-loss feedback or enhanced/reduced
restoring action against fluctuations in photon number in the context of a
quantum microlaser theory and a photon rate equation picture. However, the
theory predicts a degree of antibunching several times larger than that
observed, which may indicate the inadequacy of its treatment of atomic velocity
distributions.Comment: 4 pages, 4 figure
Persistent and multisite homophobic harassment during childhood and adolescence and its association with school difficulties in gay and bisexual men in Taiwan
Background: Homophobic harassment can compromise mental health of sexual minority youths. Objectives: This study examined the rates of persistent and multisite homophobic harassment and their associations with school difficulties during childhood and adolescence among gay and bisexual men in Taiwan. Methods: Participants were recruited through advertisements on the Facebook, Bulletin Board Systems, and the home pages of health promotion and counseling centers for the gay, lesbian, and bisexual community. The experiences of traditional and cyber harassment based on gender role nonconformity and sexual orientation of 500 gay or bisexual men were examined. The associations of multisite and persistent harassment victimization with school difficulties were evaluated. Results: A total of 239 (47.8%) and 131 (26.2%) participants experienced persistent and multisite harassment victimization, respectively. Harassment victimization was significantly associated with low satisfaction with academic performance in any stage of study. Moreover, the participants who were harassed in senior high schools were more likely to miss classes or be truant than those who were not harassed. The victims of multisite harassment at senior high schools were more likely to miss classes or be truant than those of school-only harassment. Discussion: Prevention and intervention programs are warranted to reduce homophobic harassment in sexual minority youths
Correlations of Internet Addiction Severity With Reinforcement Sensitivity and Frustration Intolerance in Adolescents With Attention-Deficit/Hyperactivity Disorder: The Moderating Effect of Medications
Background: Deviations in reinforcement sensitivity and frustration-related reactions have been proposed as components of the biopsychosocial mechanisms, which explained the high vulnerability to internet addiction (IA) among individuals with attention-deficit/hyperactivity disorder (ADHD). There is currently limited knowledge on the relationship of IA symptoms with reinforcement sensitivity and frustration intolerance, as well as factors moderating those correlations in this population.Objective: The aims of this study were (1) to examine the associations of IA symptoms severity with reinforcement sensitivity and frustration intolerance and (2) identify the moderators of these associations among adolescents diagnosed with ADHD in Taiwan.Methods: A total of 300 adolescents aged between 11 and 18 years who had been diagnosed with ADHD participated in this study. Their levels of IA severity, reinforcement sensitivity, and frustration intolerance were assessed using the Chen Internet Addiction Scale, behavioral inhibition system (BIS) and behavioral approach system (BAS), and Frustration Discomfort Scale, respectively. The associations of IA severity with reinforcement sensitivity and frustration intolerance were examined using multiple regression analysis. Possible moderators, including medications for ADHD, were tested using the standard criteria.Results: Higher fun seeking on the BAS (p = .003) and higher frustration intolerance (p = .003) were associated with more severe IA symptoms. Receiving medication for treating ADHD moderated the association between fun seeking on the BAS and severity of IA symptoms.Conclusion: Fun seeking on the BAS and frustration intolerance should be considered as targets in prevention and intervention programs for IA among adolescents with ADHD
Relationship between borderline personality symptoms and Internet addiction: The mediating effects of mental health problems
Aim To examine the relationship between borderline personality symptoms and Internet addiction as well as the mediating role of mental health problems between them. Methods A total of 500 college students from Taiwan were recruited and assessed for symptoms of Internet addiction using the Chen Internet Addiction Scale, borderline personality symptoms using the Taiwanese version of the Borderline Symptom List and mental health problems using four subscales from the Symptom Checklist-90-Revised Scale (interpersonal sensitivity, depression, anxiety, and hostility). Structural equation modeling (SEM) was used to test our hypothesis that borderline personality symptoms are associated with the severity of Internet addiction directly and also through the mediation of mental health problems. Results SEM analysis revealed that all paths in the hypothesized model were significant, indicating that borderline personality symptoms were directly related to the severity of Internet addiction as well as indirectly related to the severity of Internet addiction by increasing the severity of mental health problems. Conclusion Borderline personality symptoms and mental health problems should be taken into consideration when designing intervention programs for Internet addiction
Bidirectional associations between hyperopia, myopia, astigmatism, and strabismus, and attention-deficit/hyperactivity disorder in children: a national population-based cohort study
Objectives: The present study analyzed the reciprocal relationships between four common pediatric ophthalmic diseases (i.e., hyperopia, myopia, astigmatism, and strabismus) and attention‐deficit/hyperactivity disorder (ADHD) in children. Methods: This study enrolled 86,028 children with ADHD and 1,798,673 children without ADHD in the Taiwan Maternal and Child Health Database who were born at any time from 2004 to 2017. Cox proportional hazards regression models were used to estimate the bidirectional relationships of the four ophthalmic diseases with ADHD in children after adjusting for age, sex, and gestational age at birth. Survival curves for time-to-event variables were estimated using the Kaplan-Meier method, and the log-rank test was used to compare the curves. Results: The results indicated that ADHD significantly predicted the occurrence of hyperopia, myopia, astigmatism, and strabismus. Furthermore, hyperopia, myopia, astigmatism, and strabismus significantly predicted the occurrence of ADHD. The time between enrollment and ADHD diagnosis was shorter for patients with ophthalmic diseases than for the control group, and the time between enrollment and ophthalmic disease diagnosis was also shorter for ADHD patients than for the control group. Sex differences were found in the associations between ADHD and ophthalmic diseases. Conclusion: Clinicians should monitor children with ADHD for hyperopia, myopia, astigmatism, and strabismus to ensure appropriate treatment, and vice versa
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