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There was no previous meta-analysis investigating the efficacy/tolerability of psychostimulants for symptoms of attention-deficit hyperactivity disorder (ADHD) in preschool children.
Databases including PubMed, the Cochrane Library, EMBASE, ScienceDirect, and ClinicalTrials.gov were searched from inception to March 2022 for randomized controlled trials (RCTs) on therapeutic efficacy of psychostimulants against ADHD symptoms in preschool children (age ≤6 years) compared with placebos. Primary outcomes were (a) changes in ADHD symptoms evaluated by validated rating scales from parents’/teacher’s observation, or (b) post-intervention improvements in neuropsychological performance. Secondary outcomes were risks of adverse events.
Meta-analysis of nine eligible trials including 544 preschool children (mean age=4.86 years, female=11.98%, median treatment duration=4.33 weeks) supported the efficacy of psychostimulants against global symptoms from observations of parents (Hedges’ g=0.6152, p<0.0001) and teachers (Hedges’ g=0.6563, p=0.0039). Efficacy of psychostimulants was also noted against symptoms of inattention and hyperactivity/impulsivity, especially the latter (i.e., main symptoms in preschool children). Moreover, male gender, older age, and longer treatment duration were associated with better efficacy. Regarding adverse events, only the risk of poor appetite was higher in the psychostimulant group (odds ratio [OR]=2.39). However, the qualities of evidence were low to very low, indicating potential discrepancy between the true and estimated effect.
Our results showed that psychostimulants might be beneficial for preschool children with ADHD, especially hyperactivity/impulsivity from teachers’ observation, with tolerable side effects. Nevertheless, the true magnitude of the effect needs to be confirmed with more research due to low to very low certainty of the evidence.
This paper extends the standard double-exponential jump-diffusion (DEJD) model to allow for successive jumps to bring about different effects on the asset price process. The double-exponentially distributed jump sizes are no longer assumed to have the same parameters; instead, we assume that these parameters may take a series of different values to reflect growing or diminishing effects from these jumps. The mathematical analysis of the stock price requires an introduction of a number of distributions that are extended from the hypoexponential (HE) distribution. Under such a generalized setting, the European option price is derived in closed-form which ensures its computational convenience. Through our numerical examples, we examine the effects on the return distributions from the growing and diminishing severity of the upcoming jumps expected in the near future, and investigate how the option prices and the shapes of the implied volatility smiles are influenced by the varying severity of jumps. These results demonstrate the benefits of the modeling flexibility provided by our extension.
Problematic internet use, especially in people with substance use disorder, may negatively affect their quality of life (QoL). However, it is unclear whether sleep quality is a key mediator in the association between problematic internet use and QoL among people with substance use disorder.
This study aimed to investigate the relationship between problematic internet use and QoL and how sleep quality may mediate the association between these two variables.
Overall, 319 people (85% male) with substance use disorder (mean age 42.2 years, s.d. 8.9) participated in a cross-sectional study in Taiwan. The Smartphone Application-Based Addiction Scale, Bergan Social Media Addiction Scale, Internet Gaming Disorder-Short Form, Pittsburgh Sleep Quality Index and World Health Organization Quality of Life Questionnaire Brief Version were used.
The prevalence of sleep problems was 56%. There were significant and direct associations between sleep quality and two types of problematic internet use, and between sleep quality and different dimensions of QoL. All types of problematic internet use were significantly and negatively correlated with QoL. Mediated effects of sleep quality in relationships between the different types of problematic internet use and all dimensions of QoL were significant, except for problematic use of social media.
Different types of problematic internet use in people with substance use disorder may be directly associated with reduced QoL. Sleep quality as a significant mediator in this association may be an underlying mechanism to explain pathways between problematic internet use and QoL in this population.
The severity of COVID-19 remains high worldwide. Therefore, millions of individuals are likely to suffer from fear of COVID-19 and related mental health factors.
The present systematic review and meta-analysis aimed to synthesize empirical evidence to understand fear of COVID-19 and its associations with mental health-related problems during this pandemic period.
Relevant studies were searched for on five databases (Scopus, ProQuest, EMBASE, PubMed Central, and ISI Web of Knowledge), using relevant terms (COVID-19-related fear, anxiety, depression, mental health-related factors, mental well-being and sleep problems). All studies were included for analyses irrespective of their methodological quality, and the impact of quality on pooled effect size was examined by subgroup analysis.
The meta-analysis pooled data from 91 studies comprising 88 320 participants (mean age 38.88 years; 60.66% females) from 36 countries. The pooled estimated mean of fear of COVID-19 was 13.11 (out of 35), using the Fear of COVID-19 Scale. The associations between fear of COVID-19 and mental health-related factors were mostly moderate (Fisher's z = 0.56 for mental health-related factors; 0.54 for anxiety; 0.42 for stress; 0.40 for depression; 0.29 for sleep problems and –0.24 for mental well-being). Methodological quality did not affect these associations.
Fear of COVID-19 has associations with various mental health-related factors. Therefore, programmes for reducing fear of COVID-19 and improving mental health are needed.
Background: Among patients with schizophrenia, there is evidence of a negative association between self-stigma and subjective quality of life (SQoL), and self-esteem was an important mediator in the association. We attempted to use a longitudinal study to investigate the aforementioned mediation on a sample with schizophrenia. Methods: We used longitudinal data retrieved from medical records of a psychiatric centre between June 2014 and December 2015. In the data, we retrieved information of self-stigma using the Self-Stigma Scale — Short; SQoL, using the WHO questionnaire on the Quality of Life — Short Form; and self-esteem, using the Rosenberg Self-Esteem Scale. All the measures were evaluated five times. Linear mixed-effect models accompanied by Sobel tests were used to tackle the mediating effects. Results: Data from 74 patients (57 males) with schizophrenia were eligible for analysis; their mean (SD) age was 39.53 (10.67); mean age of onset was 22.95 (8.38). Self-esteem was a mediator for patients in physical (p = .039), psychological (p = .003), and social SQoL (p = .004), but not in environment SQoL (p = .051). Conclusion: Based on our findings, mental health professionals could tailor different programs to patients with schizophrenia, such as self-stigma reduction and self-esteem improvement programs. However, treatment as a whole should be sensitive to both self-stigma and self-esteem. Also, we should consider individuals’ health and wellbeing from social perspectives of disability rather than the medical model of disability emphasising symptoms and medications.
The Zarit Burden Interview (ZBI) is a commonly used self-report to assess caregiver burden. A 12-item short form of the ZBI has been developed; however, its measurement invariance has not been examined across some different demographics. It is unclear whether different genders and educational levels of a population interpret the ZBI items similarly. Therefore, this study aimed to examine the measurement invariance of the 12-item ZBI across gender and educational levels in a Taiwanese sample.
Caregivers who had a family member with dementia (n = 270) completed the ZBI through telephone interviews. Three confirmatory factor analysis (CFA) models were conducted: Model 1 was the configural model, Model 2 constrained all factor loadings, Model 3 constrained all factor loadings and item intercepts. Multiple group CFAs and the differential item functioning (DIF) contrast under Rasch analyses were used to detect measurement invariance across males (n = 100) and females (n = 170) and across educational levels of junior high schools and below (n = 86) and senior high schools and above (n = 183).
The fit index differences between models supported the measurement invariance across gender and across educational levels (∆ comparative fit index (CFI) = −0.010 and 0.003; ∆ root mean square error of approximation (RMSEA) = −0.006 to 0.004). No substantial DIF contrast was found across gender and educational levels (value = −0.36 to 0.29).
The ZBI is appropriate for combined use and for comparisons in caregivers across gender and different educational levels in Taiwan.
The WHOQOL-BREF, a generic quality of life (QoL) instrument, has been widely used clinically and for research on older populations. However, its measurement equivalence/invariance (ME/I) has not been well examined for the elderly (≥ 65 years) across some different demographics.
The data were derived from a cross-sectional study with a convenience sampling design in Taiwan. We enrolled 244 elderly participants: men = 143 (58.6%); educational level ≤ primary school = 121 (49.6%). The ME/I was examined using multiple group confirmatory factor analysis (MGCFA) across gender and educational level.
The fit indices were satisfactory for the configural models of gender and educational level (standardized root mean square residual [SRMR] = 0.0742 and 0.0770; root mean square error of approximation [RMSEA] = 0.0655 and 0.0686; comparative fit index [CFI] = 0.953). In addition, MGCFAs showed that ME/I was supported across gender (ΔSRMR = 0.001 to 0.019; ΔRMSEA = −0.003 to 0.001; ΔCFI = −0.003 to 0.000) and educational level (ΔSRMR = 0.002 to 0.006; ΔRMSEA = −0.002 to 0.004; ΔCFI = −0.007 to 0.000).
The WHOQOL-BREF Taiwan version is appropriate for combined use and for comparisons in older people across gender and different educational levels.
Owing to energy conservation of waste heat, Lead telluride, PbTe, based materials have promising good thermoelectric properties around a range of middle temperature (Fig. 1, from 300 to 600°C), due to their high melting point, fine chemical stability, and the high figure of merit Z. The general physical properties and factors affecting the figure of merit have been reviewed. This research is focused on the n-type of PbTe materials and collocated with analysis of densities, hardness, elastic modulus, and thermoelectric properties thermoelectric figure of merit ZT=GS2T/κ (where G is electrical conductivity, S is Seebeck coefficient , T is absolute temperature, and κ is thermal conductivity). Room temperature hardness and Young’s modulus are measured by nano-indentation. In this study, the hot-press compacts under the pressure of 4 ton/cm2 can reach the maximum density about 8.2 g/cm3, and hardness and elastic modulus are 0.6 GPa and 70 GPa, respectively. The figure of merit value (ZT) of PbTe in low temperature (around 340°C) was found about 1 with carrier concentration above 1019 cm−3. These results also indicate that the powder metallurgy parameters provide potentialities for further increase of the high efficiency of energy conversion in PbTe materials.
Three types of Ganium Nitride (GaN) transistors were studied in this work. The devices were fabricated and exhibited unique characteristics over on-state current and off-state blocking performances. We also compared the performance differences of devices fabricated by multiepitaxial GaN/AlGaN layers on different substrates (Sapphire and Si) and evaluated the correlations among starting substrate, device variation, and manufacturing uniformity. The first device is a normally-on device with Sapphire substrate which shows good drain saturation current (Idsat) and breakdown characteristics, but the gate leakage current is quite large. The second device is a normally-off GaN transistor named metal-insulate-semiconductor (MIS) heterojunction field-effect transistor (MIS-HFET) which exhibits good performance with threshold voltage (Vth) of 3V and breakdown voltage (Vbd) of over 1800V. However the third device is a normally-off GaN metal-oxide-semiconductor field-elect transistor (MOSFET) structure which is rather difficult to exhibit good blocking characteristic due to inadequate doping process control of the reduce-surface-field (RESURF) region.
A novel polymer dispersant, poly(oxyethylene)-segment imide (POEM) in the structure was incorporated in the nanocrystalline TiO2 film as the electrode. The uses of the dispersants could disperse TiO2 by decreasing the van der waals force among the nanoparticles, observed by TEM. The resultant TiO2/POEM film as the photoanode rendered the dye-sensitized solar cell (DSSC) with enhanced performance. By comparing to the traditional photoanode composing of polyethylene glycol (PEG) dispersed TiO2, the POEM dispersed TiO2 provided large surface area and high roughness in the dye adsorbed film. Furthermore, the fabricated TiO2/POEM photoanode has a better light-scattering property which contributes to the improvement for the short-circuit current density (Jsc) and the power-conversion efficiency (_) of the DSSC to be 19.1 mA cm-2 and 8.7%, respectively. The performance is superior to 13.2 mA cm-2 and 7.34% for a DSSC with the photoanode containing TiO2/PEG.
Ternary Sn-In-Cu alloys are prepared and equilibrated at 250 °C for 2 to 20 weeks. The phases formed in these alloys are experimentally determined. The 250 °C Sn-In-Cu isothermal section is established according to the phase equilibrium information obtained in this study and that of the three constituent binary systems. It has eight single-phase regions, namely liquid, δ1-Cu41Sn11, ε-Cu3Sn, δ2-Cu7In3, η-(Cu6Sn5, Cu2In), Cu11In9, Cu2In3Sn, and α-(Cu) phases, 14 two-phase regions, and seven three-phase regions. In the Sn-In-Cu system at 250 °C, the η-Cu6Sn5 and η-Cu2In phases form a continuous solid solution and the ternary Cu2In3Sn compound is observed. The δ1-Cu41Sn11 phase is stabilized at 250 °C with the introduction of indium although it transforms into α-(Cu) and ε-Cu3Sn phases via a eutectoid reaction around 350 °C in the binary Sn-Cu system. Except for the Cu11In9 phase and the Cu2In3Sn ternary compound, the other binary compounds all have significant indium and tin mutual solubilities.
We reviewed genotyping and medical records of 53 patients with end-stage renal disease and methicillin-resistant Staphylococcus aureus (MRSA) bacteremia in a medical center in Taiwan. In multivariate analysis, hospitalization within the previous year was independently negatively associated with infection with community-associated MRSA strains, and an increased number of years of dialysis predicted the recovery of patients infected with community-associated MRSA strains.
We found out the promising catalyst materials(NiPd). The NiPd not only has the low melting point but also has the Pd enhancing the surface diffusion at low temperatures(<500'c ). With the Pd film thickness increasing, we could control the CNT density and synthesize more aligned and uniform CNTs. We also obtained the better electrical properties including lower turn-on field (3.4 V/um) and higher current density (34.3 mA/cm2) for NiPd as catalyst. For the advantages described above, we believe that the difficulty of low temperature on FED can be overcome. Further, the large area field emission display might be fabricated in the future.
To the best of our knowledge, this is the first report of external ear canal schwannoma in the English literature. Several detailed clinical and pathological features were demonstrated. We suggest that if a tender, encapsulated mass is found in the external ear canal, the diagnosis of schwannoma should be taken into consideration.
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