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This paper proposes a market model with returns assumed to follow a multivariate normal tempered stable distribution defined by a mixture of the multivariate normal distribution and the tempered stable subordinator. This distribution can capture two stylized facts: fat-tails and asymmetry, that have been empirically observed for asset return distributions. We discuss a new portfolio optimization method on the new market model, which is an extension of Markowitz's mean-variance optimization. The new optimization method considers not only reward and dispersion but also asymmetry in tails. The efficient frontier is extended to a curved surface on three-dimensional space of reward, dispersion, and asymmetry in tails. We also propose a new performance measure, which is an extension of the Sharpe ratio. Moreover, we derive closed-form solutions for portfolio managers' two important measures in portfolio construction: the marginal value-at-risk (VaR) and the marginal conditional VaR (CVaR). We illustrate the proposed model using stocks comprising the Dow Jones Industrial Average. First, perform the new portfolio optimization and then demonstrating how the marginal VaR and marginal CVaR can be used for portfolio optimization under the model. Based on this paper's empirical evidence, our framework offers realistic portfolio optimization and tractable methods for portfolio risk management. [ABSTRACT FROM AUTHOR]

Twins involve a higher risk of perinatal complications compared to singletons. We compared the risk of under five mortality between twins and singletons among late preterm and term births. The national birth data of South Korea pertaining to the years 2010–2014 linked with the mortality record of children aged under 5 years in 2010–2019 was analyzed. The final study population was 2,199,632 singletons and 62,351 twins. We conducted a survival analysis of under-five mortality with adjustment for neonatal and familial factors. Overall under-five mortality rates during the study period were 3.6 and 2.0 for twins and singletons, respectively. Although the unadjusted overall under-five mortality was higher in twins (hazard ratio [HR] = 1.80, 95% confidence interval [CI]: 1.57, 2.06, overall risk), twin birth was associated with comparable or lower risk (HR = 0.70, 95% CI: 0.58, 0.85, overall; 0.70, 95% CI: 0.56, 0.87, excluding neonatal mortality; 0.59, 95% CI: 0.40, 0.86, excluding infant mortality) after controlling for both neonatal and familial factors. Twins born at a gestational age of 34–35 weeks showed a generally lower risk of under-five mortality than their singleton counterparts, regardless of model specification. Conclusion: Among late preterm and term birth, under-5-year mortalities for twins were lower than singleton births when adjusted for neonatal and familial risk factors. This highlights the differential implication of gestational age at birth between twin and singleton in the child mortality. What is Known: • Twin births involve a higher risk of perinatal complications compared to singletons. What is New: • Among late preterm and term birth, twins showed lower under-5-year mortalities than singleton births when adjusted for neonatal and familial risk factors. • Birth at 34–35 weeks of gestation implicates different prognosis between twin and singleton in the child mortality. [ABSTRACT FROM AUTHOR]

Tourette syndrome (TS) is a neuropsychiatric disorder with involvement of genetic and environmental factors. We investigated genetic loci previously implicated in Tourette syndrome and associated disorders in interaction with pre- and perinatal adversity in relation to tic severity using a case-only (N = 518) design. We assessed 98 single-nucleotide polymorphisms (SNPs) selected from (I) top SNPs from genome-wide association studies (GWASs) of TS; (II) top SNPs from GWASs of obsessive–compulsive disorder (OCD), attention-deficit/hyperactivity disorder (ADHD), and autism spectrum disorder (ASD); (III) SNPs previously implicated in candidate-gene studies of TS; (IV) SNPs previously implicated in OCD or ASD; and (V) tagging SNPs in neurotransmitter-related candidate genes. Linear regression models were used to examine the main effects of the SNPs on tic severity, and the interaction effect of these SNPs with a cumulative pre- and perinatal adversity score. Replication was sought for SNPs that met the threshold of significance (after correcting for multiple testing) in a replication sample (N = 678). One SNP (rs7123010), previously implicated in a TS meta-analysis, was significantly related to higher tic severity. We found a gene–environment interaction for rs6539267, another top TS GWAS SNP. These findings were not independently replicated. Our study highlights the future potential of TS GWAS top hits in gene–environment studies. [ABSTRACT FROM AUTHOR]

The paper is devoted to study the portfolio optimization problem for an investor who aims to minimize the exposure to equity markets measured by the Aumann–Serrano index of riskiness. The ARMA–GARCH model with normal variance–mean mixture innovations is employed to capture the stylized facts of stock returns. Using a two-step scheme, we convert the high-dimensional optimization problem into a two-dimensional one. We further prove that the dimension reduction technique preserves the convexity of the problem as long as the risk measure is convex and monotonic. In the empirical study, we observe that the optimal portfolio outperforms benchmarks based on a 10-year backtesting window covering the financial crisis. [ABSTRACT FROM AUTHOR]

In this paper, we will discuss an approximation of the characteristic function of the first passage time for a Lévy process using the martingale approach. The characteristic function of the first passage time of the tempered stable process is provided explicitly or by an indirect numerical method. This will be applied to the perpetual American option pricing and the barrier option pricing. For the numerical illustration, we calibrate risk neutral process parameters using S&P 500 index option prices and apply those parameters to find prices of perpetual American option and barrier option. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the visual symptoms and to determine the impact of visual symptoms on vision-related quality of life (QoL) in patients with early to moderate glaucoma.Methods: A retrospective, hospital-based, cross-sectional study was conducted from July 1 to August 31, 2014, at a university referral center. A total of 176 patients with early to moderate glaucoma underwent a comprehensive ocular examination, including Humphrey visual field testing. The patients were divided into six groups based on visual symptoms that could be verified by forced-choice questions. Vision-related QoL was assessed by the Korean version of the National Eye Institute Visual Function Questionnaire 25 (K-NEI-VFQ-25). We compared the mean deviation (MD) and questionnaire scores among the groups.Results: Of 352 eyes, 107 (30.4%) were symptomatic. The most common visual symptoms were partial blurring (15.91%), followed by a missing part (7.67%) and a black part (5.97%) of the image. The symptomatic groups (blurred part and missing part) had a significantly worse MD than the asymptomatic group. The symptomatic groups tended to have more visual field defects than the asymptomatic group. The overall NEI-VFQ-25 score in the symptomatic group (black part) was significantly lower than that in the asymptomatic group. Similar effects were observed for other subscale scores, including social functioning, mental health, role difficulties, dependency, and peripheral vision.Conclusions: Vision-related QoL may be severely compromised in glaucoma patients with visual symptoms. Patients with visual disorders should be evaluated for glaucoma and QoL. [ABSTRACT FROM AUTHOR]

Purpose: To report a case of iris-fixated phakic intraocular lens (pIOL) implantation in a patient with an extremely steep cornea, shallow anterior chamber, and small corneal diameter caused by retinopathy of prematurity (ROP) and scleral encircling.Methods: Case report.Results: Iris-fixated pIOLs were implanted in a 19-year-old patient with refraction of −18.5 −0.75 × 180 in the right eye and −15.5 −1.25 × 180 in the left eye. The keratometric values were 53.50 and 51.25 diopters (D) in the right eye and 54.75 and 51.75 D in the left eye. The white-to-white diameter and anterior chamber depth were 10.6 and 3.37 mm, respectively, in the right eye and 10.5 and 3.33 mm, respectively, in the left eye.Conclusion: A small pIOL was used to guarantee a safety distance and resulted in a one-line gain in uncorrected distant visual acuity and stable endothelial cell density 1 year after surgery. An iris-fixated pIOL Vis therefore an effective option for myopic patients with ROP. [ABSTRACT FROM AUTHOR]

The objective of this study was to examine the effects of glutamine on heat-shock protein beta 1 (HSPB1) expression in bovine embryonic fibroblast cells during myogenesis. First, to elucidate the role of glutamine on HSPB1 expression during myogenesis, we treated with glutamine in myogenic lineage determinant (MyoD) over-expressed bovine embryonic fibroblast cells (BEFS-MyoD cells). Second, knockdown of HSPB1 using small interference RNA was performed to evaluate whether muscle development by glutamine is dependent on HSPB1 in BEFS-MyoD cells. As a result, glutamine promoted the mRNA level of HSPB1, Myogenin, Desmin, and mTOR as well as myotube formation, and protein synthesis (p < 0.05). The inhibition of HSPB1 expression during myogenesis has shown to repress the expression of myogenic marker genes (MyoD, Myogenin, Desmin) (p < 0.01), formation of myotubes and protein synthesis (p < 0.05). According to the results, it is concluded that glutamine regulates HSPB1 expression during myogenesis. [ABSTRACT FROM AUTHOR]

In this paper, we explore the features of a structural credit risk model wherein the firm value is driven by normal tempered stable (NTS) process belonging to the larger class of Lévy processes. For the purpose of comparability, the calibration to the term structure of a corporate bond credit spread is conducted under both NTS structural model and Merton structural model. We find that NTS structural model provides better fit for all credit ratings than Merton structural model. However, it is noticed that probabilities of default derived from the calibration of the term structure of a bond credit spread might be overestimated since the bond credit spread could contain non-default components such as illiquidity risk or asymmetric tax treatment. Hence, considering CDS spread as a reflection of the pure credit risk for the reference entity, we calibrate it in order to obtain more reasonable probability of default and obtain valid results in calibration of the market CDS spread with NTS structural model. [ABSTRACT FROM AUTHOR]

Purpose: This study investigated microglia and inflammatory cell responses after selective retina therapy (SRT) with microsecond-pulsed laser in comparison to continuous-wave laser photocoagulation (cwPC).Methods: Healthy C57BL/6 J mice were treated with either a train of short pulses (SRT; 527-nm, Q-switched, 1.7-μs pulse) or a conventional thermal continuous-wave (532-nm, 100-ms pulse duration) laser. The mice were sacrificed and their eyes were enucleated 1, 3, 7, and 14 days after both laser treatments. Pattern of cell death on retinal section was evaluated by TUNEL assay, and the distribution of activated inflammatory cells and glial cells were observed under immunohistochemistry. Consecutive changes for the expression of cytokines such as IL-1β, TNF-α, and TGF-β were also examined using immunohistochemistry, and compared among each period after quantification by Western blotting.Results: The numbers of TUNEL-positive cells in the retinal pigment epithelium (RPE) layer did not differ in SRT and cwPC lesions, but TUNEL-positive cells in neural retinas were significantly less on SRT. Vague glial cell activation was observed in SRT-treated lesions. The population of inflammatory cells was also significantly decreased after SRT, and the cells were located in the RPE layer and subretinal space. Proinflammatory cytokines, including IL-1β and TNF-α, showed significantly lower levels after SRT; conversely, the level of TGF-β was similar to the cwPC-treated lesion.Conclusions: SRT resulted in selective RPE damage without collateral thermal injury to the neural retina, and apparently produced negligible glial activation. In addition, SRT showed a markedly less inflammatory response than cwPC, which may have important therapeutic implications for several macular diseases. [ABSTRACT FROM AUTHOR]

While a growing number of studies indicate associations between experiences of bullying and autism spectrum disorder (ASD), it is not clear what roles comorbid behavioral problems may play. We investigated the experiences of children with ASD as victims and/or perpetrators of bullying. Children with ASD epidemiologically ascertained participated in a cross-sectional study. Although children with ASD showed significantly increased risk for bullying involvement compared to community children, after controlling for comorbid psychopathology and other demographic factors, increased risks for being perpetrators or victim-perpetrators disappeared while risk for being bullied/teased continued to be significantly elevated. This finding will help guide medical, educational and community personnel to effectively identify children with ASD at risk for school bullying and develop interventions. [ABSTRACT FROM AUTHOR]

Muscle aging is closely related to unhealthy late-life and organismal aging. Recently, the state of differentiated cells was shown to be critical to tissue homeostasis. Thus, understanding how fully differentiated muscle cells age is required for ensuring healthy aging. Adult Drosophila muscle is a useful model for exploring the aging process of fully differentiated cells. In this study, we investigated age-related changes of γH2AX, an indicator of DNA strand breaks, in adult Drosophila muscle to document whether its changes are correlated with muscle degeneration and lifespan. The results demonstrate that γH2AX accumulation increases in adult Drosophila thoracic and leg muscles with age. Analyses of short-, normal-, and long-lived strains indicate that the age-related increase of γH2AX is closely associated with the extent of muscle degeneration, cleaved caspase-3 and poly-ubiquitin aggregates, and longevity. Further analysis of muscle-specific knockdown of heterochromatin protein 1a revealed that the excessive γH2AX accumulation in thoracic and leg muscles induces accelerated degeneration and decreases longevity. These data suggest a strong correlation between age-related muscle damage and lifespan in Drosophila. Our findings indicate that γH2AX may be a reliable biomarker for assessing muscle aging in Drosophila. [ABSTRACT FROM AUTHOR]

The Studies to Advance Autism Research and Treatment Network conducted a randomized trial with citalopram in children with Pervasive developmental disorders (PDDs). We present the rationale, design and sample characteristics of the citalopram trial. Subjects (128 boys, 21 girls) had a mean age of 9.3 (±3.12) years; 132 (88.6%) were diagnosed with autistic disorder (4.7% with Asperger's Disorder; 6.7% with PDD-not otherwise specified). Less than half of the subjects were intellectually disabled; 117 (78.5%) were rated Moderate or Marked on the Clinical Global Impression for Severity. Study measures were similar to previous Research Units on Pediatric Psychopharmacology trials. Subjects in this trial were slightly older and more likely to have complaints of repetitive behavior than participants in RUPP trials. [ABSTRACT FROM AUTHOR]

Synaptosomal plasma membrane vesicles (SPMV) were isolated from fresh bovine cerebral cortex by several well-known procedures, and the best procedure was selected by enzymatic and morphological standards. The SPMV isolated by the modified procedure of Smith and Loh showed the highest purity. The specific activities of Na, K-ATPase, acetylcholinesterase and 5′-nucleotidase were about 5.6-fold, 2.5-fold and 3.3-fold, respetively, enriched in the plasma membrane fraction as compared to those of the crude homogenate. Electron microscopic examination also showed that the membranes were in vesicular form. [ABSTRACT FROM AUTHOR]

Purpose: PEERS® for Adolescents is an evidence-based social skills training program developed for individuals with autism spectrum disorder (ASD), which is now widely implemented by community providers in clinics and schools. However, majority of past efficacy studies on PEERS® were conducted in controlled research settings, with limited information about its effectiveness when delivered in the community. We sought to examine the effects of PEERS® on social functioning and mental health outcomes when delivered in an outpatient autism specialty clinic.Clinical data from 45 adolescents with social challenges (age range: 11–18 years old; 31.1% female assigned at birth) were extracted for secondary analyses. Paired t-tests were performed to examine the pre- to post-intervention changes in social and mental health outcomes. Correlations between pre- and post-change scores of outcome measures were examined.Self-reported social skills knowledge, caregiver-reported social skills (measured by the Social Skills Improvement Systems) and the number of get-togethers hosted, increased significantly from pre- to post-intervention. Additionally, caregiver-reported anxiety and self-reported loneliness significantly decreased from pre- to post-intervention. Exploratory analyses showed that increases in caregiver-reported social skills were associated with decreases in self-reported loneliness.Our findings provide evidence supporting the efficacy of PEERS® for improving social knowledge and skills of adolescents with social challenges when delivered in the community. The current study also showed the potential benefit of PEERS® for improving adolescent mental health.Methods: PEERS® for Adolescents is an evidence-based social skills training program developed for individuals with autism spectrum disorder (ASD), which is now widely implemented by community providers in clinics and schools. However, majority of past efficacy studies on PEERS® were conducted in controlled research settings, with limited information about its effectiveness when delivered in the community. We sought to examine the effects of PEERS® on social functioning and mental health outcomes when delivered in an outpatient autism specialty clinic.Clinical data from 45 adolescents with social challenges (age range: 11–18 years old; 31.1% female assigned at birth) were extracted for secondary analyses. Paired t-tests were performed to examine the pre- to post-intervention changes in social and mental health outcomes. Correlations between pre- and post-change scores of outcome measures were examined.Self-reported social skills knowledge, caregiver-reported social skills (measured by the Social Skills Improvement Systems) and the number of get-togethers hosted, increased significantly from pre- to post-intervention. Additionally, caregiver-reported anxiety and self-reported loneliness significantly decreased from pre- to post-intervention. Exploratory analyses showed that increases in caregiver-reported social skills were associated with decreases in self-reported loneliness.Our findings provide evidence supporting the efficacy of PEERS® for improving social knowledge and skills of adolescents with social challenges when delivered in the community. The current study also showed the potential benefit of PEERS® for improving adolescent mental health.Results: PEERS® for Adolescents is an evidence-based social skills training program developed for individuals with autism spectrum disorder (ASD), which is now widely implemented by community providers in clinics and schools. However, majority of past efficacy studies on PEERS® were conducted in controlled research settings, with limited information about its effectiveness when delivered in the community. We sought to examine the effects of PEERS® on social functioning and mental health outcomes when delivered in an outpatient autism specialty clinic.Clinical data from 45 adolescents with social challenges (age range: 11–18 years old; 31.1% female assigned at birth) were extracted for secondary analyses. Paired t-tests were performed to examine the pre- to post-intervention changes in social and mental health outcomes. Correlations between pre- and post-change scores of outcome measures were examined.Self-reported social skills knowledge, caregiver-reported social skills (measured by the Social Skills Improvement Systems) and the number of get-togethers hosted, increased significantly from pre- to post-intervention. Additionally, caregiver-reported anxiety and self-reported loneliness significantly decreased from pre- to post-intervention. Exploratory analyses showed that increases in caregiver-reported social skills were associated with decreases in self-reported loneliness.Our findings provide evidence supporting the efficacy of PEERS® for improving social knowledge and skills of adolescents with social challenges when delivered in the community. The current study also showed the potential benefit of PEERS® for improving adolescent mental health.Conclusions: PEERS® for Adolescents is an evidence-based social skills training program developed for individuals with autism spectrum disorder (ASD), which is now widely implemented by community providers in clinics and schools. However, majority of past efficacy studies on PEERS® were conducted in controlled research settings, with limited information about its effectiveness when delivered in the community. We sought to examine the effects of PEERS® on social functioning and mental health outcomes when delivered in an outpatient autism specialty clinic.Clinical data from 45 adolescents with social challenges (age range: 11–18 years old; 31.1% female assigned at birth) were extracted for secondary analyses. Paired t-tests were performed to examine the pre- to post-intervention changes in social and mental health outcomes. Correlations between pre- and post-change scores of outcome measures were examined.Self-reported social skills knowledge, caregiver-reported social skills (measured by the Social Skills Improvement Systems) and the number of get-togethers hosted, increased significantly from pre- to post-intervention. Additionally, caregiver-reported anxiety and self-reported loneliness significantly decreased from pre- to post-intervention. Exploratory analyses showed that increases in caregiver-reported social skills were associated with decreases in self-reported loneliness.Our findings provide evidence supporting the efficacy of PEERS® for improving social knowledge and skills of adolescents with social challenges when delivered in the community. The current study also showed the potential benefit of PEERS® for improving adolescent mental health. [ABSTRACT FROM AUTHOR]