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Over the past two decades, early detection and early intervention in psychosis have become essential goals of psychiatry. However, clinical impressions are insufficient for predicting psychosis outcomes in clinical high-risk (CHR) individuals; a more rigorous and objective model is needed. This study aims to develop and internally validate a model for predicting the transition to psychosis within 10 years.
Two hundred and eight help-seeking individuals who fulfilled the CHR criteria were enrolled from the prospective, naturalistic cohort program for CHR at the Seoul Youth Clinic (SYC). The least absolute shrinkage and selection operator (LASSO)-penalized Cox regression was used to develop a predictive model for a psychotic transition. We performed k-means clustering and survival analysis to stratify the risk of psychosis.
The predictive model, which includes clinical and cognitive variables, identified the following six baseline variables as important predictors: 1-year percentage decrease in the Global Assessment of Functioning score, IQ, California Verbal Learning Test score, Strange Stories test score, and scores in two domains of the Social Functioning Scale. The predictive model showed a cross-validated Harrell's C-index of 0.78 and identified three subclusters with significantly different risk levels.
Overall, our predictive model showed a predictive ability and could facilitate a personalized therapeutic approach to different risks in high-risk individuals.
Background: After the Middle East respiratory syndrome coronavirus outbreak in Korea in 2015, the government newly established the additional reimbursement for infection prevention to encourage infection control activities in the hospitals. The new policy was announced in December 2015 and was implemented in September 2016. We evaluated how infection control activities improved in hospitals after the change of government policy in Korea. Methods: Three cross-sectional surveys using the WHO Hand Hygiene Self-Assessment Framework (HHSAF) were conducted in 2013, 2015, and 2017. Using multivariable linear regression model including hospital characteristics, we analyzed the changes in total HHSAF scores according to the survey time. Results: In total, 32 hospitals participated in the survey in 2013, 52 in 2015, and 101 in 2017. The number of inpatient beds per infection control professionals decreased from 324 in 2013 to 303 in 2015 and 179 in 2017. Most hospitals were at intermediate or advanced levels of progress (90.6% in 2013, 86.6% in 2015, and 94.1% in 2017). In a multivariable linear regression model, the total HHSAF scores were significantly associated with hospital teaching status (β coefficient of major teaching hospital, 52.6; 95% CI, 8.9–96.4; P = .018), bed size (β coefficient of 100-bed increase, 5.1; 95% CI, 0.3–9.8; P = .038), and survey time (β coefficient of 2017 survey, 45.1; 95% CI, 19.3–70.9; P = .001). Conclusions: After the national policy implementation, the number of infection control professionals increased, and the promotion of hand hygiene activities was strengthened in Korean hospitals.
Obsession and delusion are theoretically distinct from each other in terms of reality testing. Despite such phenomenological distinction, no extant studies have examined the identification of common and distinct neural correlates of obsession and delusion by employing biologically grounded methods. Here, we investigated dimensional effects of obsession and delusion spanning across the traditional diagnostic boundaries reflected upon the resting-state functional connectivity (RSFC) using connectome-wide association studies (CWAS).
Our study sample comprised of 96 patients with obsessive–compulsive disorder, 75 patients with schizophrenia, and 65 healthy controls. A connectome-wide analysis was conducted to examine the relationship between obsession and delusion severity and RFSC using multivariate distance-based matrix regression.
Obsession was associated with the supplementary motor area, precentral gyrus, and superior parietal lobule, while delusion was associated with the precuneus. Follow-up seed-based RSFC and modularity analyses revealed that obsession was related to aberrant inter-network connectivity strength. Additional inter-network analyses demonstrated the association between obsession severity and inter-network connectivity between the frontoparietal control network and the dorsal attention network.
Our CWAS study based on the Research Domain Criteria (RDoC) provides novel evidence for the circuit-level functional dysconnectivity associated with obsession and delusion severity across diagnostic boundaries. Further refinement and accumulation of biomarkers from studies embedded within the RDoC framework would provide useful information in treating individuals who have some obsession or delusion symptoms but cannot be identified by the category of clinical symptoms alone.
For decades, fructose intake has been recognised as an environmental risk for metabolic syndromes and diseases. Here we comprehensively examined the effects of fructose intake on mice liver transcriptomes. Fructose-supplemented water (34 %; w/v) was fed to both male and female C57BL/6N mice at their free will for 6 weeks, followed by hepatic transcriptomics analysis. Based on our criteria, differentially expressed genes (DEG) were selected and subjected to further computational analyses to predict key pathways and upstream regulator(s). Subsequently, predicted genes and pathways from the transcriptomics dataset were validated via quantitative RT-PCR analyses. As a result, we identified eighty-nine down-regulated and eighty-eight up-regulated mRNA in fructose-fed mice livers. These DEG were subjected to bioinformatics analysis tools in which DEG were mainly enriched in xenobiotic metabolic processes; further, in the Ingenuity Pathway Analysis software, it was suggested that the aryl hydrocarbon receptor (AhR) is an upstream regulator governing overall changes, while fructose suppresses the AhR signalling pathway. In our quantitative RT-PCR validation, we confirmed that fructose suppressed AhR signalling through modulating expressions of transcription factor (AhR nuclear translocator; Arnt) and upstream regulators (Ncor2, and Rb1). Altogether, we demonstrated that ad libitum fructose intake suppresses the canonical AhR signalling pathway in C57BL/6N mice liver. Based on our current observations, further studies are warranted, especially with regard to the effects of co-exposure to fructose on (1) other types of carcinogens and (2) inflammation-inducing agents (or even diets such as a high-fat diet), to find implications of fructose-induced AhR suppression.
Refugees commonly experience difficulties with emotional processing, such as alexithymia, due to stressful or traumatic experiences. However, the functional connectivity of the amygdala, which is central to emotional processing, has yet to be assessed in refugees. Thus, the present study investigated the resting-state functional connectivity of the amygdala and its association with emotional processing in North Korean (NK) refugees.
This study included 45 NK refugees and 40 native South Koreans (SK). All participants were administered the Toronto Alexithymia Scale (TAS), Beck Depression Inventory (BDI), and Clinician-administered PTSD Scale (CAPS), and differences between NK refugees and native SK in terms of resting-state functional connectivity of the amygdala were assessed. Additionally, the association between the strength of amygdala connectivity and the TAS score was examined.
Resting-state connectivity values from the left amygdala to the bilateral dorsolateral prefrontal cortex (dlPFC) and dorsal anterior cingulate cortex (dACC) were higher in NK refugees than in native SK. Additionally, the strength of connectivity between the left amygdala and right dlPFC was positively associated with TAS score after controlling for the number of traumatic experiences and BDI and CAPS scores.
The present study found that NK refugees exhibited heightened frontal–amygdala connectivity, and that this connectivity was correlated with alexithymia. The present results suggest that increased frontal–amygdala connectivity in refugees may represent frontal down-regulation of the amygdala, which in turn may produce alexithymia.
Residual stress is generally evaluated using indentation by comparing the indentation curves of stressed and stress-free states. Here, we suggest a new method that can evaluate surface residual stress without indentation testing on stress-free specimen using stress-independent indentation parameters and an analysis of indentation contact morphology for the stress-free state. We found that several indentation parameters are independent of the stress by Vickers indentation testing on various stress states. The indentation contact morphology can be represented by indentation parameters including stress-independent ones, and by applying the stress-independent parameters obtained from the stressed state to the indentation contact depth function, we can estimate an indentation curve for stress-free state. The estimated curve matches well with the experimental stress-free indentation curve, and it was also confirmed that the applied stress values evaluated by comparing the estimated curve with the stressed indentation curve agree well with the reference values obtained from strain gauge.
This paper aims to test two types of legislative shirking in a new democracy, South Korea. Using the lame-duck sessions of the Korean National Assembly, we test whether a legislator shirks in voting participation and in voting decisions. We weave two competing motivations of legislative shirking in voting participation – that to secure more leisure time and that to utilize the last, valuable voting opportunity – into a synthetic hypothesis and test it with two-part hurdle models. To test a shirking in voting participation hypothesis, we analyze legislators’ choices on bills that are supposedly related to the interests of constituents or political parties. Empirical results strongly support our shirking in voting participation claims, while only partial evidence is found on shirking in voting decisions. The findings suggest that, besides the trade-off between labor and leisure, some legislators deem the lame-duck sessions an opportunity to express their own preferences unconstrained.
We examined whether hypotension in very low birth weight infants aged⩽1 week was associated with hospital morbidities and overall mortality. Further, we studied whether hypotension was associated with poor neurodevelopmental outcomes in these patients at the corrected age of 18 months. A total of 166 very low birth weight infants were studied during this period. Hospital outcomes and neurodevelopmental outcomes at the corrected age of 18 months were evaluated. Among the 166 very low birth weight infants, 95 patients (57.2%) experienced hypotension at⩽1 week and were associated with an increased incidence of morbidities and mortality. At the corrected age of 18 months, hypotension of the⩽1 week group had significantly lower scores in all three – cognitive, language, and motor – composites of the Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III) screening tests. In addition, a multivariable logistic regression analysis showed that longer mechanical ventilation and periventricular leukomalacia were additionally associated with worse cognitive and language neurodevelopmental outcomes. Hypotension in very low birth weight infants within 1 week of life was associated with increased morbidities and overall mortality. It was also associated with an increased risk of cognitive and language outcomes.
We trace Sn nanoparticles (NPs) produced from SnO2 nanotubes (NTs) during lithiation initialized by high energy e-beam irradiation. The growth dynamics of Sn NPs is visualized in liquid electrolytes by graphene liquid cell transmission electron microscopy. The observation reveals that Sn NPs grow on the surface of SnO2 NTs via coalescence and the final shape of agglomerated NPs is governed by surface energy of the Sn NPs and the interfacial energy between Sn NPs and SnO2 NTs. Our result will likely benefit more rational material design of the ideal interface for facile ion insertion.
We demonstrate the tungsten disulfide (WS2) thin film catalysts prepared by the sulfurization of vacuum deposited WO3 thin films for efficient hydrogen production with over 90% Faradaic efficiency. The 23-nm-thick WS2 thin film catalyst heterojunction with p-type silicon photocathode could exhibit a photocurrent density of 8.3 mA/cm2 at 0 V versus a reversible hydrogen electrode (RHE), a low onset potential of 0.2 V versus RHE when photocurrent density reaches −1 mA/cm2 and long-term stability over 10 h. The enhanced catalytic activities of WS2/p-Si photocathodes compared with the bare p-Si photocathode originate from a number of edge sites in the synthesized polycrystalline thin films, which could act as hydrogen evolution catalyst.