Recently, rhenium disulfide (ReS 2) monolayers were experimentally extracted by conventional mechanical exfoliation technique from as-grown ReS 2 crystals. Unlike the well-known members of transition metal dichalcogenides (TMDs), ReS 2 crystallizes in a stable distorted-1T structure and lacks an indirect to direct gap crossover. Here we present an experimental and theoretical study of the formation, energetics, and stability of the most prominent lattice defects in monolayer ReS 2. Experimentally, irradiation with 3-MeV He +2 ions was used to break the strong covalent bonds in ReS 2 flakes. Photoluminescence measurements showed that the luminescence from monolayers is mostly unchanged after highly energetic α particle irradiation. In order to understand the energetics of possible vacancies in ReS 2 we performed systematic first-principles calculations. Our calculations revealed that the formation of a single sulfur vacancy has the lowest formation energy in both Re and S rich conditions and a random distribution of such defects are energetically more preferable. Sulfur point defects do not result in any spin polarization whereas the creation of Re-containing point defects induce magnetization with a net magnetic moment of 1-3µ B. Experimentally observed easy formation of sulfur vacancies is in good agreement with first-principles calculations.

WHAT'S KNOWN ON THIS SUBJECT: Major depression is common among adolescents. The PHQ-9 has good sensitivity and specificity for detecting depression among adolescents in primary care settings. However, no study has examined the psychometric properties of the PHQ-9 among Chinese adolescents in school settings. WHAT THIS STUDY ADDS:This is the first study to validate the use of the PHQ-9, Patient Health Questionnaire-2 item, and Patient Health Questionnaire-1 item among Chinese adolescents in Taiwan. The PHQ-9 and its 2 subscales have good sensitivity and specificity for detecting depression among school adolescents.abstract OBJECTIVE: The aim of this study was to determine the reliability and validity of a Chinese version of the Patient Health Questionnaire-9 item (PHQ-9) and its 2 subscales (1 item and 2 items) for the screening of major depressive disorder (MDD) among adolescents in Taiwan.METHODS: A total of 2257 adolescents were recruited from high schools in Taipei. The participants completed assessments including demographic information, the Chinese version of the PHQ-9, and the Rosenberg Self-Esteem Scale, and data on the number of physical illnesses and mental health service utilizations were recorded. Among them, 430 were retested using the PHQ-9 within 2 weeks. Child psychiatrists interviewed a subsample of the adolescents (n = 165) using the Kiddie-Schedule for Affective Disorder and Schizophrenia Epidemiological Version as the criterion standard. RESULTS:The PHQ-9 had good internal consistency (a = 0.84) and acceptable test-retest reliability (0.80). The participants with higher PHQ-9 scores were more likely to have MDD. Principal component factor analysis of the PHQ-9 yielded a 1-factor structure, which accounted for 45.3% of the variance. A PHQ-9 score $15 had a sensitivity of 0.72 and a specificity of 0.95 for recognizing MDD. The area under the receiver operating characteristic curve was 0.90. The screening accuracy of the 2 subscales was also satisfactory, with a Patient Health Questionnaire-2 item cutoff of $3 being 94.4% sensitive and 82.5% specific and a Patient Health Questionnaire-1 item cutoff of $2 being 61.1% sensitive and 87.7% specific. CONCLUSIONS:The PHQ-9 and its 2 subscales appear to be reliable and valid for detecting MDD among ethnic Chinese adolescents in Taiwan.

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ObjectivePatients with systemic lupus erythematosus (SLE) are susceptible to herpes simplex virus (HSV) infection, which occasionally leads to severe complications including meningoencephalitis and keratitis. However, few attempts to analyse the associated incidence and risk factors have been made.MethodsWe enrolled patients with SLE recorded between 1997 and 2012 and compared the incidence rate (IR) of severe HSV infection, including meningoencephalitis, septicaemia, ocular and visceral involvement, and other specific complications demanding hospitalisation, with that of a non-SLE cohort. A Cox multivariate proportional hazards model was applied to analyse the risk factors of severe HSV infection in patients with SLE.ResultsA total of 122 520 subjects (24 504 patients with SLE and 98 016 age-matched and sex-matched non-SLE controls) were included, and a higher IR of severe HSV infection was revealed in the SLE group (IR ratio=3.93, p<0.001). In patients with SLE, previous oral and genital infection (HR=2.29, p=0.049), intravenous steroid pulse therapy (HR=5.32, p<0.001) and daily oral dose of over 7.5 mg of prednisolone (HR=1.59, p=0.024) were independent risk factors for severe HSV infection, whereas age of ≤18 (HR=0.45, p=0.029) was a protective factor.ConclusionsPatients with SLE are at higher risk of severe HSV infection, and related risk factors include being older than 18 years, having a history of HSV mucocutaneous infection, recent receipt of steroid pulse therapy and a daily oral dose of steroid over 7.5 mg prednisolone.

Breast cancer is the most common cancer among women worldwide. Adjuvant chemotherapy has significantly reduced mortality but increased cognitive impairments, including attention function, making quality of life issues a crucial concern. This study enrolled nineteen breast cancer patients who were treated with standard chemotherapy within 6 months and 20 sex-matched healthy controls to investigate the brain effects of chemotherapy. All participants underwent resting-state functional magnetic resonance imaging (rs-fMRI) with mean fractional amplitude of low-frequency fluctuation (mfALFF) analysis and were correlated with neuropsychological tests, including the Mini-Mental State Examination (MMSE), the Cognitive and Affective Mindfulness Scale-Revised (CAMS-R), and the Impact of Event Scale-Revised (IES-R), to explore the possible underlying mechanism of cognitive alternations. We found increased mfALFF over the frontoparietal lobe and decreased mfALFF over the occipital lobe in the cancer patients compared with the healthy controls; the altered brain regions may be associated with the dorsal attention network (DAN) and may be explained by a compensatory mechanism. Both MMSE and CAMS-R scores showed a positive correlation with mfALFF in the occipital lobe but a negative correlation in the frontoparietal lobe. By contrast, IES-R scores showed a positive correlation with mfALFF in the frontoparietal lobe but a negative correlation in the occipital lobe. These alterations are potentially related to the effects of both chemotherapy and psychological distress. Future research involving a larger sample size of patients with breast cancer is recommended.