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Worldwide, significant efforts are made to identify energy sources that can help achieve carbon neutrality and promote sustainable development. The development of a catalyst that combines durability and high performance is essential for the commercialization of proton‐exchange membrane fuel cells (PEMFCs). In a fuel cell, carbon corrosion occurs during startup and shutdown due to improper local flooding caused by inadequate water management. In this study, a Pt‐based catalyst is designed with excellent durability and high activity. Introducing a metal oxide layer modified with Pt/multi‐walled carbon nanotubes reduces the direct contact between carbon and the fuel cell environment. This helps prevent carbon corrosion and inhibits the separation, aggregation, and growth of Pt nanoparticles. Moreover, the catalyst exhibits enhanced oxygen reduction activity due to the electronic effect of the metal oxide layer that is coated on it. In this study, by implementing a carbon erosion acceleration protocol, excellent catalytic properties during a load‐cycling experiment consisting of 5,000 cycles are reported. The practical application of the developed catalyst in PEMFCs offers an effective approach to developing Pt‐group metal catalysts with exceptional activity. [ABSTRACT FROM AUTHOR]

Acute or repetitive exposure to ultraviolet (UV) cause disruptions to the skin barrier and subsequent inflammatory skin disease. 4‐phenylpyridine (4‐PP) is a constituent of Brassica campestris L. ssp. Pekinensis and its effect on skin inflammation and molecular target remain unclear. The purpose of this study is to confirm the anti‐inflammatory efficacy of 4‐PP on UVB‐induced skin inflammation in human keratinocytes HaCaT and mouse skin and validation of its molecular target. 4‐PP also attenuated UVB‐induced phosphorylation of p38/mitogen‐activated protein kinase kinase (MKK) 3/6, c‐Jun N‐terminal kinase 1/2, MKK 4/7, extracellular‐signal‐regulated kinase 1/2, mitogen‐activated protein kinase 1/2. Additionally, 4‐PP inhibited UVB‐induced phosphorylation of epidermal growth factor receptor (EGFR) Y1068, Y1045 and 854 residues but not the proto‐oncogene tyrosine‐protein kinase c‐Src. Drug affinity responsive target stability assay revealed that 4‐PP directly binds to c‐Src and inhibits pronase c‐proteolysis. Knockdown of c‐Src inhibited UVB‐induced COX‐2 expression and phosphorylation of MAPKs and EGFR in HaCaT cells. Dorsal treatment of 4‐PP prevented UVB (0.5 J/cm2)‐induced skin thickness, phosphorylation of EGFR and COX‐2 expression in mouse skin. Our findings suggest that 4‐PP can be used as anti‐inflammatory agent with an effect of skin inflammation by inhibiting the COX‐2 expression via suppressing the c‐Src/EGFR/MAPKs signalling pathway. [ABSTRACT FROM AUTHOR]

The objective of this study is to understand how humidity and temperature affect the degradation behavior of polydioxanone (PDO). After changing the degradation environments, we examined the weight loss, pH value, thermal properties, mechanical properties, morphology, and rheological properties of the PDO samples. The specimens were kept in a wet or dry condition for 12 weeks. During degradation, weight retention, pH values, tensile strength, and viscosity decreased, whereas the melting temperature (Tm) and degree of crystallinity (Dc) increased. Compared with dry samples, wet PDO samples exhibited a higher hydrolysis rate. Also, higher temperatures led to more hydrolysis. Humidity was found to decrease the molecular weight of the samples and increase the degradation rate. [ABSTRACT FROM AUTHOR]

Abstract: Background: Fever rather than diarrhea or vomiting was the most common symptom of neonatal rotavirus (RV) infection in our previous study. We investigated whether RV infection is a major cause of neonatal fever and compared the clinical characteristics of bacterial infection, viral infection and unknown causes of neonatal fever. Method: We reviewed the electronic medical records of 48 newborns aged ≤28 days who were admitted to the Special Care Nursery of Hanyang University Guri Hospital for fever (≥38°C) from 2005 to 2009. All the newborns underwent complete blood count, urinalysis, C‐reactive protein, cultures of blood, urine, and cerebrospinal fluid as well as stool RV enzyme‐linked immunosorbent assay. Respiratory virus polymerase chain reaction for cough or rhinorrhea, and stool culture for diarrhea were also done. Results: All the babies were term, with mean age 13 ± 8 days and peak body temperature 38.5 ± 0.5°C. The causes of neonatal fever were viral (44%), bacterial (10%) and unknown (46%). The viral infections included RV (n = 12), enterovirus (n = 6), respiratory syncytial virus (n = 2), and rhinovirus (n = 1). All the rotavirus genotypes were G4P[6]. Only three of 12 RV‐infected febrile newborns had diarrhea. The bacterial infections included three cases of urinary tract infection (Escherichia coli, n = 2; Klebsiella pneumoniae, n = 1), and two cases of sepsis complicated with meningitis (all Streptococcus agalactiae). Conclusions: RV infection is the most common single cause of neonatal fever. It may be necessary to include stool RV tests for febrile newborns. [ABSTRACT FROM AUTHOR]

Background & Aims The aim of this study was to reveal nationwide seroprevalence of HCV infection in South Korea by a large-scale survey. Methods From January to December 2009, a total of 291 314 adults underwent health check-up in 29 centres nationwide. The data concerning anti- HCV antibody and biochemical tests were obtained from all participants. Among subjects with positive anti- HCV, such data as HCV RNA, genotypes and treatment detail were additionally analysed. Results Using an estimated 2009 population of Korea, the age, sex and area-adjusted anti- HCV positive rate was 0.78%. Anti- HCV prevalence in female patients (0.83%) was higher than that in male patients (0.75%). Gradual increase in anti- HCV positivity was observed, from 0.34% in those aged 20-29 years to 2.31% in those >70 years. The age- and sex-adjusted anti- HCV prevalence varied in different areas, being higher in Busan and Jeonnam (1.53-2.07%), mid-level in Seoul and surrounding districts (0.50-0.61%) and lower in Jeju (0.23%). The comparative analysis of laboratory variables between anti- HCV (+) and anti- HCV (−) group revealed significantly higher levels of alanine aminotransferase and lower levels of serum lipids in anti- HCV (+) group. Among 1 718 anti- HCV positive subjects, serum HCV RNA was measured only in 478 people, of whom 268 (56.1%) patients had detectable HCV RNA in serum. Among 50 patients for whom assessment of response to antiviral therapy was feasible, overall sustained virological response was achieved in 84% of patients. Conclusion The prevalence of HCV infection is low in South Korea. Studies to analyse risk factors are warranted to reduce HCV infection. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this study is to propose a novel method of optimal display gamma curve using display performance and image contents characteristic which is displayed on the device. For the aspect of the display performance, image quality is a complex task because it is a consequence of interaction of quality attribute. However, the gamma attribute is the most dominant aspect for the display quality. Applying the curve of optimal display gamma can improve both the quality of displayed image and visibility for the environment of mobile device usage. In this study, we suggest a method of optimal display gamma curve based on display performance, image contents characteristic, and the environment of mobile device usage. [ABSTRACT FROM AUTHOR]

Layered double hydroxides (LDHs) have emerged as promising nanomaterials for human health and although it has achieved some progress on this matter, their application within bioengineering is not fully addressed. This prompted to subject fibroblasts to two compositions of LDHs (Mg2Al‐Cl and Zn2Al‐Cl), considering an acute response. First, LDH particles are addressed by scanning electron microscopy, and no significant effect of the cell culture medium on the shape of LDHs particles is reported although it seems to adsorb some soluble proteins as proposed by energy‐dispersive X‐ray analysis. These LDHs release magnesium, zinc, and aluminum, but there is no cytotoxic or biocompatibility effects. The data show interference to fibroblast adhesion by driving the reorganization of actin‐based cytoskeleton, preliminarily to cell cycle progression. Additionally, these molecular findings are validated by performing a functional wound‐healing assay, which is accompanied by a dynamic extracellular matrix remodeling in response to the LDHs. Altogether, the results show that LDHs nanomaterials modulate cell adhesion, proliferation, and migration, delineating new advances on the biomaterial field applied in the context of soft tissue bioengineering, which must be explored in health disorders, such as wound healing in burn injuries. [ABSTRACT FROM AUTHOR]

The industrial potential of Saccharomyces cerevisiae has extended beyond its traditional use in fermentation to various applications, including recombinant protein production. Herein, comparative genomics was performed with three industrial S. cerevisiae strains and revealed a heterozygous diploid genome for the 98-5 and KSD-YC strains (exploited for rice wine fermentation) and a haploid genome for strain Y2805 (used for recombinant protein production). Phylogenomic analysis indicated that Y2805 was closely associated with the reference strain S288C, whereas KSD-YC and 98-5 were grouped with Asian and European wine strains, respectively. Particularly, a single nucleotide polymorphism (SNP) in FDC1, involved in the biosynthesis of 4-vinylguaiacol (4-VG, a phenolic compound with a clove-like aroma), was found in KSD-YC, consistent with its lack of 4-VG production. Phenotype microarray (PM) analysis showed that KSD-YC and 98-5 displayed broader substrate utilization than S288C and Y2805. The SNPs detected by genome comparison were mapped to the genes responsible for the observed phenotypic differences. In addition, detailed information on the structural organization of Y2805 selection markers was validated by Sanger sequencing. Integrated genomics and PM analysis elucidated the evolutionary history and genetic diversity of industrial S. cerevisiae strains, providing a platform to improve fermentation processes and genetic manipulation., (© 2023 The Authors. Microbial Biotechnology published by Applied Microbiology International and John Wiley & Sons Ltd.)

Although new pharmaceutical therapy options have recently become available, hydroxyurea is still the most commonly used and affordable treatment option for sickle cell disease (SCD). This study aimed to update the evidence on hydroxyurea adherence and its association with clinical and economic outcomes among individuals with SCD. This retrospective study used Texas Medicaid claims data from 09/2011-08/2016. Individuals were included if they had ≥1 inpatient or ≥2 outpatient SCD diagnoses, had ≥1 hydroxyurea prescription, were 2-63 years of age, and were continuously enrolled in Texas Medicaid between 6 months before and 1 year after the first hydroxyurea prescription fill date (index date). Hydroxyurea adherence (Medication Possession Ratio; MPR), vaso-occlusive crisis (VOC)-related outcomes, healthcare utilization and expenditures (SCD-related and all-cause) during the 1 year following the index date were measured. Bivariate and multivariable analyses were used to address the study objectives. Among 1035 included individuals (age: 18.8 ± 12.5 years, female: 52.1%), 20.9% were adherent to hydroxyurea (defined as MPR≥0.8). After adjustment for demographic and clinical characteristics, compared to being non-adherent, adhering to hydroxyurea was significantly associated with: a lower risk (Odds Ratio [OR] = 0.480, p = .0007) and hazard rate (Hazard Ratio [HR] = 0.748, p = .0005) of a VOC event, fewer VOC events (Incidence Rate Ratio [IRR] = 0.767, p = .0009), fewer VOC-related hospital days (IRR = 0.593, p = .0003), fewer all-cause and SCD-related hospitalizations (IRR = 0.712, p = .0008; IRR = 0.707, p = .0008, respectively) and emergency department visits (IRR = 0.768, p = .0037; IRR = 0.746, p = .0041, respectively), and lower SCD-related total healthcare expenditures (IRR = 0.796, p = .0266). Efforts to increase adherence to hydroxyurea could improve clinical and economic outcomes among individuals with SCD., (© 2022 Wiley Periodicals LLC.)

Seasonal influenza causes mild to severe respiratory infections and significant morbidity, especially in older adults. Transcriptomic analysis in populations across multiple flu seasons has provided insights into the molecular determinants of vaccine response. Still, the metabolic changes that underlie the immune response to influenza vaccination remain poorly characterized. We performed untargeted metabolomics to analyze plasma metabolites in a cohort of younger and older subjects before and after influenza vaccination to identify vaccine-induced molecular signatures. Metabolomic and transcriptomic data were combined to define networks of gene and metabolic signatures indicative of high and low antibody response in these individuals. We observed age-related differences in metabolic baselines and signatures of antibody response to influenza vaccination and the abundance of α-linolenic and linoleic acids, sterol esters, fatty-acylcarnitines, and triacylglycerol metabolism. We identified a metabolomic signature associated with age-dependent vaccine response, finding increased tryptophan and decreased polyunsaturated fatty acids (PUFAs) in young high responders (HRs), while fatty acid synthesis and cholesteryl esters accumulated in older HRs. Integrated metabolomic and transcriptomic analysis shows that depletion of PUFAs, which are building blocks for prostaglandins and other lipid immunomodulators, in young HR subjects at Day 28 is related to a robust immune response to influenza vaccination. Increased glycerophospholipid levels were associated with an inflammatory response in older HRs to flu vaccination. This multi-omics approach uncovered age-related molecular markers associated with influenza vaccine response and provides insight into vaccine-induced metabolic responses that may help guide development of more effective influenza vaccines., (© 2022 The Authors. Aging Cell published by Anatomical Society and John Wiley & Sons Ltd.)

Increasing use of innovative items in operational assessments has shedded new light on the polytomous testlet models. In this study, we examine performance of several scoring models when polytomous items exhibit random testlet effects. Four models are considered for investigation: the partial credit model (PCM), testlet-as-a-polytomous-item model (TPIM), random-effect testlet model (RTM), and fixed-effect testlet model (FTM). The performance of the models was evaluated in two adaptive testings where testlets have nonzero random effects. The outcomes of the study suggest that, despite the manifest random testlet effects, PCM, FTM, and RTM perform comparably in trait recovery and examinee classification. The overall accuracy of PCM and FTM in trait inference was comparable to that of RTM. TPIM consistently underestimated population variance and led to significant overestimation of measurement precision, showing limited utility for operational use. The results of the study provide practical implications for using the polytomous testlet scoring models., (© 2021 The British Psychological Society.)

A monotone relationship between a true score (τ) and a latent trait level (θ) has been a key assumption for many psychometric applications. The monotonicity property in dichotomous response models is evident as a result of a transformation via a test characteristic curve. Monotonicity in polytomous models, in contrast, is not immediately obvious because item response functions are determined by a set of response category curves, which are conceivably non-monotonic in θ. The purpose of the present note is to demonstrate strict monotonicity in ordered polytomous item response models. Five models that are widely used in operational assessments are considered for proof: the generalized partial credit model (Muraki, 1992, Applied Psychological Measurement, 16, 159), the nominal model (Bock, 1972, Psychometrika, 37, 29), the partial credit model (Masters, 1982, Psychometrika, 47, 147), the rating scale model (Andrich, 1978, Psychometrika, 43, 561), and the graded response model (Samejima, 1972, A general model for free-response data (Psychometric Monograph no. 18). Psychometric Society, Richmond). The study asserts that the item response functions in these models strictly increase in θ and thus there exists strict monotonicity between τ and θ under certain specified conditions. This conclusion validates the practice of customarily using τ in place of θ in applied settings and provides theoretical grounds for one-to-one transformations between the two scales., (© 2018 The British Psychological Society.)

The Cox proportional hazards model with a latent trait variable (Ranger & Ortner, 2012, Br. J. Math. Stat. Psychol., 65, 334) has shown promise in accounting for the dependency of response times from the same examinee. The model allows flexibility in shapes of response time distributions using the non-parametric baseline hazard rate while allowing parametric inference about the latent variable via exponential regression. The flexibility of the model, however, comes at the price of a significant increase in the complexity of estimating the model. The purpose of this study is to propose a new estimation approach to overcome this difficulty in model estimation. The new procedure is based on the penalized partial likelihood estimator in which the partial likelihood is maximized in the presence of a penalty function. The potential of the proposed method is corroborated by a series of simulation studies for fitting the proportional hazards latent trait model to psychological and educational testing data. The application of the estimation method to the hierarchical framework (van der Linden, 2007, Psychometrika, 72, 287) is also illustrated for jointly analysing response times and accuracy scores., (© 2016 The British Psychological Society.)

A decreased growth rate of recombinant cells is observed when a cloned gene protein encoded in a multicopy plasmid is induced from a strong promoter. This negative effect on the cell growth rate may be the consequence of alternate use or reallocation of energy, precursor metabolites, and protein synthesizing machinery. In order to analyze the causes for this adverse effect, we have studied how genetic elements present in multicopy plasmids affect the growth of recombinant Escherichia coli (K12 delta H1 delta trpEA). Turning on of the PL promoter, whether or not protein-coding sequences were present downstream of the promoter, decreased the growth of the recombinant cells by 15-50%. This result suggests that the essential factor(s) for cell growth may be sequestered by the genetic elements present in the plasmids and thus may cause the decreased growth. The negative effect of the de-repressed PL promoters on cell growth was partially reversed when the par sequence from pSC101 was inserted into the same plasmid. In each case when the plasmid carried only the PL promoter, the PL promoter followed by the N-terminal part of the protein-coding region, or the PL promoter followed by complete sequences encoding a protein, the par sequence exhibited a positive effect on the growth rate of the recombinant cells, which usually grow at a slower rate than the host cell.(ABSTRACT TRUNCATED AT 250 WORDS)