Search

Ja Young Cheon,1 Su Jun Kim,1 Young Ha Rhee,2 Oh Hyeong Kwon,3 Won Ho Park11Department of Advance Organic Materials and Textile System Engineering, Chungnam National University, Daejeon 34134, Korea; 2Department of Microbiology and Molecular Biology, Chungnam National University, Daejeon 34134, Korea; 3Department of Polymer Science and Engineering, Kumoh National Institute of Technology, Gumi 39177, KoreaPurpose: An important application of silver nanoparticles (Ag NPs) is their use as an antimicrobial and wound dressing material. The aim of this study is to investigate the morphological dependence on the antimicrobial activity and cellular response of Ag NPs.Materials and methods: Ag NPs of various shapes were synthesized in an aqueous solution using a simple method. The morphology of the synthesized Ag NPs was observed via TEM imaging. The antimicrobial activity of the Ag NPs with different morphologies was evaluated against various microorganisms (Escherichia coli [E. coli], Staphylococcus aureus [S. aureus], Pseudomonas aeruginosa [P. aeruginosa]). The antimicrobial activity of the Ag NPs was also examined according to the concentration in terms of the growth rate of E. coli.Results: The TEM images indicated that the Ag NPs with different morphologies (sphere, disk and triangular plate) had been successfully synthesized. The antimicrobial activity obtained from the inhibition zone was in the order of spherical Ag NPs > disk Ag NPs > triangular plate Ag NPs. In contrast, fibroblast cells grew well in all types of Ag NPs when the cell viability was evaluated via an MTT assay. An inductively coupled plasma mass assay showed that the difference in the antimicrobial activities of the Ag NPs was closely associated with the difference in the release rate of the Ag ions due to the difference in the surface area of the Ag NPs.Conclusion: The morphological dependence of the antimicrobial activity of the Ag NPs can be explained by the difference in the Ag ion release depending on the shape. Therefore, it will be possible to control the antimicrobial activity by controlling the shape and size of the Ag NPs.Keywords: silver nanoparticles, Ag NPs, different shape, antimicrobial activity, cell viability, ion release

Orostachys japonicus is a popular traditional medicinal herb used in Asian countries. This study is focused on evaluating its role in lipid and glucose metabolism in cell and animal models to establish the plant as an anti-obesity and antidiabetic herb. A butanol fraction of O. japonicus was used in the study. The lipid production was evaluated by the Oil Red O technique while the expression of adipogenic markers by Western blotting and RT-PCR using 3T3-L1 preadipocyte. The effect on glucose uptake activity was evaluated in C2C12 myoblast cells. The animal study was carried out in C57BL mice to evaluate anti-obesity activity using the high-fat diet model. The evaluation of serum lipid, blood glucose, adipogenic and fibrosis markers in the liver, and fat deposition in the liver and adipose tissue (by histology) of mice was conducted. Butanol fraction of O. japonicus significantly inhibited the lipid production in the 3T3-L1 cells and reduced the expression of PPARγ, C/EBPα, SREBP-1c and aP2. It enhanced glucose uptake in insulin-resistant C2C12 myoblast cells. It reduced body weight, triglycerides, and blood glucose in the obese mice. It significantly inhibited lipid accumulation in the liver and adipose tissue of obese mice along with suppression of expression of adipogenic and fibrosis markers in the liver. In summary, supporting the previous results, this study helped to establish the potent anti-obesity, antidiabetic, and liver-protecting effect of the butanol fraction of O. japonicus .

Compared to infant formula, breast milk is the best source of nutrition for infants; it not only improves the neonatal intestinal function, but also regulates the immune system and gut microbiota composition. However, probiotic-fortified infant formula may further enhance the infant gut environment by overcoming the limitations of traditional infant formula. We investigated the probiotic formula administration for one month by comparing 118 Korean infants into the following three groups: infants in each group fed with breast milk (50), probiotic formula (35), or placebo formula-fed group (33). Probiotic formula improved stool consistency and defecation frequency compared to placebo formula-fed group. The probiotic formula helped maintaining the level of secretory immunoglobulin A (sIgA), which had remarkably decreased over time in placebo formula-fed infants (compared to weeks 0 and 4). Moreover, probiotic formula decreased the acidity of stool and considerably increased the butyrate concentration. Furthermore, the fecal microbiota of each group was evaluated at weeks 0 and 4. The microbial composition was distinct between each groups, and the abundance of health-promoting bacteria increased in the probiotic formula compared to the placebo formula-fed group. In summary, supplementation of probiotic infant formula can help optimize the infant gut environment, microbial composition, and metabolic activity of the microbiota, mimicking those of breast milk., Competing Interests: The authors declare no potential conflicts of interest., (© Korean Society for Food Science of Animal Resources.)

In this study, a range of carbon nanotube yarn (CNTY) architectures was examined and controlled by chemical modification to gain a deeper understanding of CNTY load-bearing systems and produce lightweight and superstrong CNTYs. The architecture of CNTY, which has polymer layers surrounding a compact bundle without hampering the original state of the CNTs in the bundle, is a favorable design for further chemical cross-linking and for enhancing the load-transfer efficiency, as confirmed by in situ Raman spectroscopy under a stress load. The resulting CNTY exhibited excellent mechanical performance that exceeded the specific strength of the benchmark, high-performance fibers. This exceptional strength of the CNTY makes it a promising candidate for the cable of a space elevator traveling from the Earth to the International Space Station given its strength of 4.35 GPa/(g cm -3 ), which can withstand the self-weight of a 440 km cable.

Purpose Conditions affecting the elbow, forearm, wrist, and hand can cause debilitating pain and loss of function in the working population. While there is knowledge about intervention options for this region of the body, there is limited research on systematically identifying the predictors of return to work in this population. Methods A systematic literature review identified all English-language studies that assess predictors of return to work for people with elbow, wrist, and hand conditions from 2009 to 2021 using PRISMA guidelines. Studies that examined exclusively shoulder injuries, randomized control trials, non-human studies, case studies, case reports, case series, and narrative reviews were excluded. Participants of included studies must have a health-related condition of the fingers, wrist, forearm, and elbow that is preventing work participation and must be 16 years and older. Included studies must be observational, longitudinal, and include a return to work outcome. Results Nineteen out of 170 studies were included. Average time away from work varied between seven to 304 days. Positive predictors of early return to work include: demographics, type of injury, type of treatment, work status, physical factors, psychological factors, use of self-reported outcome measures, and self-reported pain. Conclusion Five clinician recommendations were developed based on the findings of our systematic review. Clinicians should consider the type of work, use of outcome measures, psychological factors, hospitalization, and salary. These recommendations are intended to influence the behavior of clinicians when determining prognosis for return to work of people with elbow, wrist, and hand conditions., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

In mammals, the gut microbiome is vertically transmitted during maternal lactation at birth. In this study, we investigated the gut microbiome and diets of muskox, a large herbivore inhabiting in the high Arctic. We compared the microbiota composition using bacterial 16S rRNA gene sequencing and diets using stable isotope analysis of muskox feces of six female adults and four calves on Ella Island, East Greenland. Firmicutes were the most abundant bacterial phylum in both the adults and calves, comprising 94.36% and 94.03%, respectively. Significant differences were observed in the relative abundance of the two Firmicutes families. The adults were primarily dominated by Ruminococcaceae (73.90%), and the calves were dominated by both Ruminococcaceae (56.25%) and Lachnospiraceae (24.00%). Stable isotope analysis of the feces in the study area revealed that both adults and calves had similar ranges of 13 C and 15 N, likely derived from the dominant diet plants. Despite their similar diets, the different gut microbiome compositions in muskox adults and calves indicate that the gut microbiome of the calves may not be fully colonized to the extent of that of the adults., Competing Interests: The authors have declared that no competing interests exist., (© 2022 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

Fiber-type solid-state supercapacitors are being widely investigated as stable power supply for next-generation wearable and flexible electronics. Integrating both high charge storage capability and superior mechanical properties into one fiber is crucial to realize fiber-type solid-state supercapacitors. In this study, we design a “jeweled necklace”–like hybrid composite fiber comprising double-walled carbon nanotube yarn and metal-organic frameworks (MOFs). Subsequent heat treatment transforms MOFs into MOF-derived carbon (MDC), thereby maximizing energy storage capability while retaining the superior mechanical properties. The hybrid fibers with tunable properties, including thickness and MDC loading amount, exhibit a high energy density of 7.54 milliwatt-hour per cubic centimeter at a power density of 190.94 milliwatt per cubic centimeter. The mechanical robustness of the hybrid fibers allows them to operate under various mechanical deformation conditions. Furthermore, it is demonstrated that the resulting superstrong fiber delivers sufficient power to switch on light-emitting diodes by itself while suspending 10-kilogram weight.

Despite significant advances in the development of flexible gel polymer electrolytes (GPEs), there are still problems to be addressed to apply them to flexible electric double layer capacitors (EDLCs), including interfacial interactions between the electrolyte and electrode under deformation. Previously reported EDLCs using GPEs have laminated structures with weak interfacial interactions between the electrode and electrolyte, leading to fragility upon elongation and low power density due to lower utilization of the surface area of the carbon material in the electrode. To overcome these problems, we present a new strategy for constructing an epoxy-based GPE that can provide strong adhesion between electrode and electrolyte. The GPE is synthesized by polymerization of epoxy and an ionic liquid. This GPE shows high flexibility up to 509% and excellent adhesive properties that enable strong chemical bonding between the electrode and electrolyte. Moreover, the GPE is stable at high voltage and high temperature with high ionic conductivity of ∼10 -3 S cm -1 . EDLCs based on the developed GPE exhibit good compatibility between the electrode and electrolyte and work properly when deformed. The EDLCs also show a high specific capacitance of 99 F g -1 , energy density of 113 W h kg -1 , and power density of 4.5 kW g -1 . The excellent performance of the GPE gives it tremendous potential for use in next generation electronic devices such as wearable devices., Competing Interests: The authors declare that they have no conflict of interest., (This journal is © The Royal Society of Chemistry.)

Although self-rated health (SRH), a subjective measure of overall health status, associates with metabolic abnormalities, studies on the relationship between SRH and non-alcoholic fatty liver disease (NAFLD), a hepatic manifestation of metabolic syndrome, are limited. In this study, we evaluated whether or not SRH predicts the risk of incident NAFLD. This cohort study was performed in a sample of 148,313 Korean adults free of ultrasound-diagnosed NAFLD at baseline with annual or biennial follow-up for a median of 3.7 years. SRH and NAFLD were measured at baseline and follow-up visits. NAFLD was determined based on the ultrasound-diagnosed fatty liver without excessive alcohol consumption or any other cause. Hazard ratios with 95% confidence intervals were estimated via a parametric proportional hazards model. During 522,696.1 person-years of follow-up, 23,855 individuals with new-onset NAFLD were identified (incidence rate, 45.6 per 1,000 person-years). After adjustments for possible confounders including total calorie intake, sleep duration, and depressive symptoms, the multivariate-adjusted hazard ratios (95% confidence intervals) for incident NAFLD comparing good, fair, and poor or very poor SRH to very good SRH were 1.06 (0.97-1.14), 1.18 (1.09-1.27), and 1.24 (1.13-1.37), respectively. This association of SRH with incident NAFLD remained significant after accounting for changes in SRH and confounders during follow-up and was similar across clinically relevant subgroups. In a large-scale cohort study of apparently healthy Korean adults, poor SRH was independently and positively associated with incident NAFLD risk, indicating a predictive role of SRH as a health measure in NAFLD.

Electrospun scaffolds have been widely used in tissue engineering due to their similar structure to native extracellular matrices (ECM). However, one of the obstacles limiting the application of electrospun scaffolds for tissue engineering is the nano-sized pores, which inhibit cell infiltration into the scaffolds. To overcome this limitation, we approached to make layers which are consisted of cells onto the electrospun sheet and then tubular structure was constructed by rolling. We called this as 'Cell Matrix Engineering' because the electrospun sheets were combined with the cells to form one matrix. They maintained 3-D tubular structures well and their diameters were 4.1 mm (±0.1 mm). We compared the mechanical and biological properties of various vascular grafts with the electrospun PLCL sheets of different thickness. In these experiments, the vascular graft made with thin sheets showed a better cell proliferation and attachment than the grafts made with thick sheets because the thin layer allowed for more efficient mass transfer and better permeability than the thick layer. Culturing under physiological pulsatile flow condition was demonstrated in this work. These dynamic conditions provided the improved mass transport and aerobic cell metabolism. Therefore, the Cell Matrix Engineered vascular graft holds a great promise for clinical applications by overcoming the limitations associated with conventional scaffolds.

In this study, silver chloride nanoparticles (AgCl NPs) were prepared using chitosan oligomer (CHI) and chitosan oligomer derivatives (CHI-FITC). The CHI and CHI-FITC were used as markers to confirm the formation of AgCl NPs using their fluorescence properties as well as stabilizers. The fluorescence properties of CHI and CHI-FITC were monitored by a luminescence spectrophotometer, and the morphology of the AgCl NPs was further confirmed by transmission electron microscopy (TEM) and X-ray diffraction (XRD). The fluorescence of CHI and CHI-FITC was quenched by the formation of AgCl NPs, and the Stern-Volmer equation was used to compare the two types of stabilizer. The CHI and CHI-FITC stabilizer were linear and nonlinear, respectively, with respect to the Stern-Volmer equation, and considered to be usable as fluorescence indicators to confirm the formation behavior of AgCl NPs through fluorescence quenching., Competing Interests: The authors declare no conflict of interest.

Objective: To investigate the role of maternal serum placenta growth factor (PlGF) and quadruple test parameters in predicting the risk of small for gestational age (SGA) infants of mothers without preeclampsia., Materials and Methods: We prospectively enrolled 300 pregnant patients who underwent blood sampling at 15-18 weeks gestation and followed them until delivery. Cases with SGA neonate delivery (n = 100) were compared with matched AGA neonate controls (n = 200). The plasma PlGF and quadruple markers were measured by enzyme-linked immunosorbent assay. The results were analyzed with Mann-Whitney U tests, and regression analysis was used to develop a model for the prediction of SGA., Results: Women who delivered SGA neonates had decreased levels of PlGF (median 0.71 MoM versus 0.7 MoM; p < 0.01), hCG (median 0.97 MoM versus 1.06 MoM; p = 0.046) and uE3 (median 0.92 MoM versus 1.04 MoM) compared to the AGA group. AFP, hCG and inhibin-A levels did not differ significantly. A PlGF concentration <0.37 MoM had a sensitivity of 28.0% (95% CI: 19.5-37.9) and a specificity of 89.5% (95% CI: 84.4-93.4) for the prediction of SGA neonates without PE., Conclusion: SGA neonates in the absence of PE could potentially be identified at 15-18 weeks of pregnancy., (Copyright © 2017. Published by Elsevier B.V.)

Objective: To evaluate the predictive factors associated with the success of medical abortion by misoprostol monotherapy within 24 hours in the first trimester of pregnancy., Methods: The records of 228 women with miscarriage up to 11 weeks of gestational age who underwent medical abortion by intravaginal misoprostol monotherapy were reviewed. Success of abortion was defined as complete expulsion of the conceptus without the need for surgical intervention. Outcomes of interest were success of abortion within 24 hours following administration of misoprostol., Results: Among 222 women who continued the process of medical abortion for 24 hours, 209 (94.1%) had a successfully completed abortion. Multivariate logistic regression showed that serum β-human chorionic gonadotropin (β-hCG) above 40,000 mIU/mL is significantly associated with failed medical abortion within 24 hours (odds ratio [OR], 7.13; 95% confidence interval [CI], 1.60-37.32; P =0.011). The area under the receiver operating characteristic curve of β-hCG level associated with successful abortion within 24 hours was 0.705 (95% CI, 0.63-0.77; P =0.007). Previous vaginal delivery seems to be significantly associated with successful abortion within 24 hours on univariate analysis ( P =0.037), but the association was lost in multivariate analysis., Conclusion: Misoprostol monotherapy has a high success rate for first trimester abortion. Women with serum β-hCG less than 40,000 mIU/mL are likely to achieve a successful abortion within 24 hours after intravaginal administration of misoprostol., Competing Interests: Conflict of interest: No potential conflict of interest relevant to this article was reported.

Hyperlipidaemia and hypercholesterolaemia are risk factors of atherosclerosis and cardiovascular disease. The reference range of lipids during pregnancy has not yet been clearly set. This study sought to measure lipid parameters and pentraxin (PTX) 3 levels in low-risk pregnant women. The participants had serial blood samples taken between their 6th-9th week, 10th-13th week, 14th-19th week, 24th-29th week and 35th-40th week (as long as there were no contractions), during the labour period, and 2 days after delivery. The same tests were carried out on cord blood after delivery. There were 116 participants, of which 72 were included in the study and 44 were excluded. Total-c, HDL-c, LDL-c, TG and PTX3 increased as the pregnancy progressed. During labour, Total-c, HDL-c, LDL-c and PTX3 increased, but TG decreased. After delivery, TG and PTX3 increased but other parameters decreased from the value measured during the 35th-40th week. This study measured changes in lipid profiles and PTX3 during pregnancy, labour and after delivery, establishing a foundation for future studies.

Objective: To investigate the relationship between placenta and perinatal outcomes, in preterm infants born to mothers with preterm premature rupture of fetal membrane (PPROM)., Methods: We report detailed histology of placentas and perinatal outcomes of infants from 79 PPROM pregnancies. Placental histologic pattern and adverse perinatal outcomes were assessed by logistic regression, adjusting for gestational age at birth, birth weight and interval from rupture of membrane to delivery., Results: Mean gestational age at membrane rupture was 29.5 ± 3.4 weeks. The incidence of histologic chorioamnionitis (HCA), fetal inflammatory response (FIR) and vascular thrombotic abnormalities in placental histologic examination were 63.3, 25.3 and 78.5%, respectively. Neonates with FIR showed significantly higher incidence of periventricular leukomalacia (PVL) (85% versus 59.3%, p = 0.0364) at brain ultrasonography, than neonates without FIR, in univariate analysis, but not in logistic regression analysis. In logistic regression analysis, the odds ratio of low Apgar score at 1 min in the neonates with clinical chorioamnionitis was 5.009 (95% CI, 1.242-20.195). The odds ratio of neonatal seizure in the neonates with FIR and vascular thrombotic problem was 7.486 (95% CI, 1.617-34.653)., Conclusions: Our findings support the association between FIR with vascular thrombotic problem in placenta and neonatal seizure, in pregnancies with PPROM.

Objective: To evaluate the relationships between sociodemographic factors, reproductive history, and subsequent risk of osteoarthritis (OA) or pain of the hip, knee, and back in Korean women., Materials and Methods: This study included data of 5101 women aged over 50 years, taken from the Korean National Health and Nutritional Examination Survey V from 2010 to 2012. Women were stratified according to parity, as well as delivery mode. Multivariate logistic regression analysis was conducted to evaluate relationships between radiographic OA or symptomatically possible OA (back, knee, or hip), and historical factors., Results: Vaginal delivery was associated with an increased risk of symptomatic back OA [odds ratio (OR) 1.75, 95% confidence interval (CI) 1.062, 2.881] but was not associated with symptomatic knee and hip OA in adjusted analysis. Radiographically, vaginal delivery was not associated with risks of back and knee OA, but was negatively associated with hip OA (OR 0.184, 95% CI 0.039, 0.863), compared to cesarean delivery. High parity (over 5) was associated with radiographic knee OA (OR 1.328, 95% CI 1.006, 1.754) in adjusted analysis. High parity (over 3) was associated with symptomatic back OA., Conclusion: Parity was associated with higher risk of radiographic knee OA. Vaginal delivery was positively associated with symptomatic back OA, but negatively associated with radiographic knee OA. Further study is required to evaluate the mechanism between delivery mode and subsequent OA., (Copyright © 2017. Published by Elsevier B.V.)

This articles reports a simple and green method for preparing uniform silver nanoparticles (AgNPs), for which self-polymerized 3,4-dihydroxy-l-phenylalanine (polyDOPA) is used as the reducing and stabilizing agent in aqueous media. The AgNPs functionalized by polyDOPA were analyzed by UV-Vis spectroscopy, high-resolution transmission electron microscopy (HR-TEM), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), Raman spectrophotometry, and X-ray diffraction (XRD) techniques. The results revealed that the polyDOPA-AgNPs with diameters of 25 nm were well dispersed due to the polyDOPA. It was noted that the polyDOPA-AgNPs showed selectivity for Pb 2+ and Cu 2+ detection with the detection limits for the two ions as low as 9.4 × 10 -5 and 8.1 × 10 -5 μM, respectively. Therefore, the polyDOPA-AgNPs can be applied to both Pb 2+ and Cu 2+ detection in real water samples. The proposed method will be useful for colorimetric detection of heavy metal ions in aqueous media., Competing Interests: The authors declare no conflict of interest.

Iron-nitrogen on carbon (Fe-N/C) catalysts have emerged as promising nonprecious metal catalysts (NPMCs) for oxygen reduction reaction (ORR) in energy conversion and storage devices. It has been widely suggested that an active site structure for Fe-N/C catalysts contains Fe-N x coordination. However, the preparation of high-performance Fe-N/C catalysts mostly involves a high-temperature pyrolysis step, which generates not only catalytically active Fe-N x sites, but also less active large iron-based particles. Herein, we report a general "silica-protective-layer-assisted" approach that can preferentially generate the catalytically active Fe-N x sites in Fe-N/C catalysts while suppressing the formation of large Fe-based particles. The catalyst preparation consisted of an adsorption of iron porphyrin precursor on carbon nanotube (CNT), silica layer overcoating, high-temperature pyrolysis, and silica layer etching, which yielded CNTs coated with thin layer of porphyrinic carbon (CNT/PC) catalysts. Temperature-controlled in situ X-ray absorption spectroscopy during the preparation of CNT/PC catalyst revealed the coordination of silica layer to stabilize the Fe-N 4 sites. The CNT/PC catalyst contained higher density of active Fe-N x sites compared to the CNT/PC prepared without silica coating. The CNT/PC showed very high ORR activity and excellent stability in alkaline media. Importantly, an alkaline anion exchange membrane fuel cell (AEMFC) with a CNT/PC-based cathode exhibited record high current and power densities among NPMC-based AEMFCs. In addition, a CNT/PC-based cathode exhibited a high volumetric current density of 320 A cm -3 in acidic proton exchange membrane fuel cell. We further demonstrated the generality of this synthetic strategy to other carbon supports.

Recently, numerous compounds have been studied in order to develop antibacterial agents, which can prevent colonized wounds from infection, and assist the wound healing. For this purpose, novel silver chloride nanoparticles stabilized with chitosan oligomer (CHI-AgCl NPs) were synthesized to investigate the influence of antibacterial chitosan oligomer (CHI) exerted by the silver chloride nanoparticles (AgCl NPs) on burn wound healing in a rat model. The CHI-AgCl NPs had a spherical morphology with a mean diameter of 42 ± 15 nm. The burn wound healing of CHI-AgCl NPs ointment was compared with untreated group, Vaseline ointment, and chitosan ointment group. The burn wound treated with CHI-AgCl NPs ointment was completely healed by 14 treatment days, and was similar to normal skin. Particularly, the regenerated collagen density became the highest in the CHI-AgCl NPs ointment group. The CHI-AgCl NPs ointment is considered a suitable healing agent for burn wounds, due to dual antibacterial activity of the AgCl NPs and CHI.

The small and large nuclear subunit molecular phylogeny of the genus Prorocentrum demonstrated that the species are dichotomized into two clades. These two clades were significantly different (one-factor ANOVA, p < 0.01) with patterns compatible for both small and large subunit Bayesian phylogenetic trees, and for a larger taxon sampled dinoflagellate phylogeny. Evaluation of the molecular divergence levels showed that intraspecies genetic variations were significantly low (t-test, p < 0.05), than those for interspecies variations (> 2.9% and > 26.8% dissimilarity in the small and large subunit [D1/D2], respectively). Based on the calculated molecular divergence, the genus comprises two genetically distinct groups that should be considered as two separate genera, thereby setting the pace for major systematic changes for the genus Prorocentrum sensu Dodge. Moreover, the information presented in this study would be useful for improving species identification, detection of novel clades from environmental samples., (© 2015 The Author(s) Journal of Eukaryotic Microbiology © 2015 International Society of Protistologists.)

Metal sulfide-based nanostructured materials have emerged as promising catalysts for hydrogen evolution reaction (HER), and significant progress has been achieved in enhancing their activity and durability for the HER. The understanding of nanoscale size-dependent catalytic activities can suggest critical information regarding catalytic reactivity, providing the scientific basis for the design of advanced catalysts. However, nanoscale size effects in metal sulfide-based HER catalysts have not yet been established fully, due to the synthetic difficulty in precisely size-controlled metal sulfide nanoparticles. Here we report the preparation of molybdenum sulfide (MoS2) nanoparticles with monolayer precision from one to four layers with the nearly constant basal plane size of 5 nm, and their size-dependent catalytic activity in the HER. Using density functional theory (DFT) calculations, we identified the most favorable single-, double-, and triple-layer MoS2 model structures for the HER, and calculated elementary step energetics of the HER over these three model structures. Combining HER activity measurements and the DFT calculation results, we establish that the turnover frequency of MoS2 nanoparticles in the HER increases in a quasi-linear manner with decreased layer numbers. Cobalt-promoted MoS2 nanoparticles also exhibited similar HER activity trend. We attribute the higher HER activity of smaller metal sulfide nanoparticles to the higher degree of oxidation, higher Mo-S coordination number, formation of the 1T phase, and lower activation energy required to overcome transition state. This insight into the nanoscale size-dependent HER activity trend will facilitate the design of advanced HER catalysts as well as other hydrotreating catalysts.

Catalytic properties of nanoparticles can be significantly enhanced by controlling nanoscale alloying and its structure. In this work, by using a facet-controlled Pt@Ni core-shell octahedron nanoparticle, we show that the nanoscale phase segregation can have directionality and be geometrically controlled to produce a Ni octahedron that is penetrated by Pt atoms along three orthogonal Cartesian axes and is coated by Pt atoms along its edges. This peculiar anisotropic diffusion of Pt core atoms along the ⟨100⟩ vertex, and then toward the ⟨110⟩ edges, is explained via the minimum strain energy for Ni-Ni pair interactions. The selective removal of the Ni-rich phase by etching then results in structurally fortified Pt-rich skeletal PtNi alloy framework nanostructures. Electrochemical evaluation of this hollow nanoframe suggests that the oxygen reduction reaction (ORR) activity is greatly improved compared to conventional Pt catalysts.

After two decades of genetic testing and research, the BRCA1 and BRCA2 genes are two of the most well-characterized genes in the human genome. As a result, variants of uncertain significance (VUS; also called variants of unknown significance) are reported less frequently than for genes that have been less thoroughly studied. However, VUS continue to be uncovered, even for BRCA1/2. The increasing use of multi-gene panels and whole-genome and whole-exome sequencing will lead to higher rates of VUS detection because more genes are being tested, and most genomic loci have been far less intensively characterized than BRCA1/2. In this article, we draw attention to ethical and policy-related issues that will emerge. Experience garnered from BRCA1/2 testing is a useful introduction to the challenges of detecting VUS in other genetic testing contexts, while features unique to BRCA1/2 suggest key differences between the BRCA experience and the current challenges of multi-gene panels in clinical care. We propose lines of research and policy development, emphasizing the importance of pooling data into a centralized open-access database for the storage of gene variants to improve VUS interpretation. In addition, establishing ethical norms and regulated practices for sharing and curating data, analytical algorithms, interpretive frameworks and patient re-contact are important policy areas.

The π-π interaction-dependent vapour pressure of phenanthrenequinone can be used to synthesize a phenanthrenequinone-confined ordered mesoporous carbon. Intimate contact between the insulating phenanthrenequinone and the conductive carbon framework improves the electrical conductivity. This enables a more complete redox reaction take place. The confinement of the phenanthrenequinone in the mesoporous carbon mitigates the diffusion of the dissolved phenanthrenequinone out of the mesoporous carbon, and improves cycling performance.

[Purpose] Although the Push-Up Plus is a useful exercise method for shoulder stabilization, few studies have examined its effects at different angles of shoulder rotation. Therefore, the present study investigated the most effective exercise method for shoulder stabilization by analyzing muscle activities of the rotator cuff muscles at different angles of shoulder rotation. [Subjects] Fifteen healthy university students in their 20s were the subjects of this study. [Methods] Changes in muscle EMG related to shoulder stabilization were analyzed by performing the Push-Up Plus in shoulder positions of neutral, internal and external rotation. [Results] The highest muscle activity was found in external rotation, and in internal rotation the pectoralis major and levator scapula showed significantly lower activities than the other positions. [Conclusion] Selectively changing the rotation angle of the shoulder for different purposes of the shoulder exercise would be an effective exercise method.

Context: Pancreatic cancer presents a wide spectrum of significant symptomatology. The high symptom burden, coupled with a rapidly fatal diagnosis, limits preparation or time for adjustment for both patients and their family caregivers. From the initial diagnosis and throughout the illness experience, the physical and emotional demands of caregiving can predispose caregivers themselves to illness and a greater risk of mortality. Understanding the negative and positive aspects of caregiving for patients with advanced pancreatic cancer will inform interventions that promote positive caregiver outcomes and support caregivers in their role., Objectives: To provide feasibility data for a larger, mixed methods, longitudinal study focused on the experience of family caregivers of patients with advanced pancreatic cancer and preliminary qualitative data to substantiate the significance of studying this caregiver population., Methods: This was a mixed methods study guided by the Stress Process Model. Eight family caregivers of patients with advanced pancreatic cancer from oncology practices of a university-affiliated medical center were surveyed., Results: The pilot results supported the ability to recruit and retain participants and informed recruitment and data collection procedures. The qualitative results provided preliminary insights into caregiver experiences during the diagnosis and treatment phases. Key findings that substantiated the significance of studying these caregivers included the caregiving context of the history of sentinel symptoms, the crisis of diagnosis, the violation of assumptions about life and health, recognition of the circle of association, and contextual factors, as well as primary and secondary stressors, coping strategies, resources, discoveries, gains and growth, associated changes/transitions, and unmet caregiver needs., Conclusion: Findings indicated caregivers' willingness to participate in research, highlighted the negative and positive aspects of the caregiver experience, and reinforced the significance of the future study and the need to develop interventions to support family caregivers in their roles., (Copyright © 2014 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.)

Nanostructured carbon materials doped with a variety of heteroatoms have shown promising electrocatalytic activity in the oxygen reduction reaction (ORR). However, understanding of the working principles that underpin the superior ORR activity observed with doped nanocarbons is still limited to predictions based on theoretical calculations. Herein, we demonstrate, for the first time, that the enhanced ORR activity in doped nanocarbons can be correlated with the variation in their nanoscale work function. A series of doped ordered mesoporous carbons (OMCs) were prepared using N, S, and O as dopants; the triple-doped, N,S,O-OMC displayed superior ORR activity and four-electron selectivity compared to the dual-doped (N,O-OMC and S,O-OMC) and the monodoped (O-OMC) OMCs. Significantly, the work functions of these heteroatom-doped OMCs, measured by Kelvin probe force microscopy, display a strong correlation with the activity and reaction kinetics for the ORR. This unprecedented experimental insight can be used to provide an explanation for the enhanced ORR activity of heteroatom-doped carbon materials.

Aim: Poor health-related quality of life (HRQOL) in patients with chronic heart failure (CHF) may be one of the most common predictors of mortality and rehospitalization. This study was conducted to identify factors affecting HRQOL in Korean patients with CHF using two HRQOL measurements., Methods: The study included a sample of 114 patients. HRQOL was measured by the Minnesota Living with Heart Failure Questionnaire (MLHFQ) and the World Health Organization's Quality of Life Instrument - Short Version (WHOQOL-BREF). Multiple regression analyses were performed to analyze the relationship between the factors and HRQOL., Results: Significant correlations were found between MLHFQ and WHOQOL-BREF in total and component scores, with the two exceptions of WHOQOL-BREF psychological and MLHFQ physical or total. The perceived economic status, functional status, and sex were factors identified as having an effect on HRQOL., Conclusion: The MLHFQ was better able to differentiate sex, comorbidity, and functional status. Further studies are needed to implement cost-effective nursing interventions for patients with CHF to improve their HRQOL., (© 2012 The Authors. Japan Journal of Nursing Science © 2012 Japan Academy of Nursing Science.)

Nanoporous metal oxide materials are ubiquitous in the material sciences because of their numerous potential applications in various areas, including adsorption, catalysis, energy conversion and storage, optoelectronics, and drug delivery. While synthetic strategies for the preparation of siliceous nanoporous materials are well-established, nonsiliceous metal oxide-based nanoporous materials still present challenges. Herein, we report a novel synthetic strategy that exploits a metal-organic framework (MOF)-driven, self-templated route toward nanoporous metal oxides via thermolysis under inert atmosphere. In this approach, an aliphatic ligand-based MOF is thermally converted to nanoporous metal oxides with highly nanocrystalline frameworks, in which aliphatic ligands act as the self-templates that are afterward evaporated to generate nanopores. We demonstrate this concept with hierarchically nanoporous magnesia (MgO) and ceria (CeO2), which have potential applicability for adsorption, catalysis, and energy storage. The pore size of these nanoporous metal oxides can be readily tuned by simple control of experimental parameters. Significantly, nanoporous MgO exhibits exceptional CO2 adsorption capacity (9.2 wt %) under conditions mimicking flue gas. This MOF-driven strategy can be expanded to other nanoporous monometallic and multimetallic oxides with a multitude of potential applications.

The high cost of the platinum-based cathode catalysts for the oxygen reduction reaction (ORR) has impeded the widespread application of polymer electrolyte fuel cells. We report on a new family of non-precious metal catalysts based on ordered mesoporous porphyrinic carbons (M-OMPC; M = Fe, Co, or FeCo) with high surface areas and tunable pore structures, which were prepared by nanocasting mesoporous silica templates with metalloporphyrin precursors. The FeCo-OMPC catalyst exhibited an excellent ORR activity in an acidic medium, higher than other non-precious metal catalysts. It showed higher kinetic current at 0.9 V than Pt/C catalysts, as well as superior long-term durability and MeOH-tolerance. Density functional theory calculations in combination with extended X-ray absorption fine structure analysis revealed a weakening of the interaction between oxygen atom and FeCo-OMPC compared to Pt/C. This effect and high surface area of FeCo-OMPC appear responsible for its significantly high ORR activity.

Purpose: The purpose of this study was to develop effective intervention programmes that can reduce family caregiver burden as they provide care to stroke patients so that family caregivers can adapt to and deal with the new circumstances from the early stages of stroke. We also intended to verify the effectiveness of the developed programme., Methods: This study employed a quasi-experimental design with a repeated-measures analysis. We included five hospitals specialized in stroke care in Seoul Metropolitan areas. Seventy-three patients from these hospitals agreed to participate in this study., Results: The score of family caregiver burden decreased by 8.07 (±18.67) in the experimental group and increased by 1.65 (±7.47) in the control group, which was a significant difference (t=2.257, P=0.027) between pre- and post-intervention. The family caregiver burden of experimental group was significantly lower than the control group (F=3.649, P=0.033)., Conclusions: The home-based individual tele-care intervention, in addition to the hospital-based group programme, was cost-effective and supportive in reducing family caregivers' burden by providing relevant information for their needs in timely manner., (© 2012 The Authors. International Nursing Review © 2012 International Council of Nurses.)

We report the preparation of highly interconnected ordered mesoporous carbon-carbon nanotube nanocomposites which show Pt-like dye-sensitized solar cell (DSSC) efficiency and remarkable long-term durability as DSSC counter electrodes.

The preparation of redox-active metal-organic framework (ra-MOF)-supported Pd nanoparticles (NPs) via the redox couple-driven method is reported, which can yield unprotected metallic NPs at room temperature within 10 min without the use of reducing agents. The Pd@ra-MOF has been exploited as a precursor of an active catalyst for CO oxidation. Under the CO oxidation reaction condition, Pd@ra-MOF is transformed into a PdOx-NiOy/C nanocomposite to generate catalytically active species in situ, and the resultant nanocatalyst shows sustainable activity through synergistic stabilization.

Developments of high-performance cost-effective electrocatalyts that can replace Pt catalysts have been a central theme in polymer electrolyte membrane fuel cells (PEMFCs) and direct methanol fuel cells (DMFCs). In this direction, nitrogen-doped carbon nanostructures free of metallic components have attracted particular attention. Here we show that directing graphitic carbon nitride frameworks into mesoporous architecture can generate a highly promising metal-free electrocatalyst for an oxygen reduction reaction (ORR) in an acidic medium. The ordered mesoporous carbon nitride (OMCN) was synthesized with a nanocasting strategy using ordered mesoporous silica as a template. A variety of characterizations revealed that the OMCN is constructed with graphitic carbon nitride frameworks and ordered arrays of uniform mesopores. The OMCN showed significantly enhanced electrocatalytic activity for ORR compared to bulk carbon nitride and ordered mesoporous carbon in terms of the current density and onset potential. A high surface area and an increased density of catalytically active nitrogen groups in the OMCN appear to contribute concomitantly to the enhanced performance of the OMCN. Furthermore, the OMCN exhibited superior durability and methanol tolerance to a Pt/C catalyst, suggesting its widespread utilization as an electrocatalyst for PEMFCs and DMFCs.

The facile synthesis of silica supported platinum nanoparticles with ultrathin titania coating to enhance metal-support interactions suitable for high temperature reactions is reported, as thermal and structure stability of metal nanoparticles is important for catalytic reactions.

A shallow-depth ground water area was investigated to identify the dominant processes governing the distribution of hydrocarbon contaminants and hydrogeochemical parameters. The ground water in the study site has been highly contaminated with petroleum hydrocarbons. A preliminary pump-and-treatment remediation technology was applied for 4 yr at the site. Multivariate analyses were applied to hydrogeochemical data obtained before and after the rainy season. The pump-and-treatment application, indigenous biodegradation, and mixing by precipitation recharge are the major factors or events involved in the distribution of geochemical parameters of the ground water in the study area. Site-specific artificial pavement also played an important role in the evolution of the ground water chemistry. A conventional graphical analysis method (Piper plot) of major ions did not effectively reveal these effects. In this study, we demonstrate the usefulness of multivariate analysis (factor and cluster analyses) using biodegradation indicator parameters, as well as major cations and anions, for the study of the ground water system in the hydrocarbon-contaminated site.

Recent molecular studies indicate two different genetic pathways leading to the development of glioblastoma; final progression of astrocytoma and de novo formation. To define the mutual relationships of cytogenetic changes in the pathogenesis of glioblastoma, molecular histopathologic alterations of p53 and epidermal growth factor receptor (EGFR) were evaluated by single stranded conformational polymorphion, reverse transcriptase-polymerase chain reaction and immunohistochemical stains in 15 primary and 21 secondary glioblastomas. Mutations in p53 gene and positive immunoreactivity to p53 protein (DO1) were more prevalent in secondary glioblastomas than in primary glioblastomas. A correlation between p53 mutations and p53 immunopositivities in glioblastomas was observed in 83.3% of the cases. All cases with positive p53 immunoreactivities showed p53 mutations; however, 13.9% of glioblastomas with p53 immuno-positivities lacked the relevant mutations. EGFR amplifications were detected in 73.3% of primary glioblastomas and 9.5% of secondary glioblastomas (p<0.001). The concurrence of p53 mutation and EGFR amplification was revealed in only 2 out of 15 primary glioblastomas and none among the secondary glioblastomas. Immunoreactivities for EGFR were noted in 66.7% of primary glioblastomas and in 9.5% of secondary glioblastomas (p<0.001). A correlation between EGFR amplification and EGFR immunopositivity in glioblastomas was observed in 91.7% of the cases. These data indicate that EGFR amplification and p53 mutations are two independent genetic events in the development of glioblastomas.

The distributions of hydrocarbon contaminants and hydrogeochemical parameters were investigated in a shallow sand aquifer highly contaminated with petroleum hydrocarbons leaked from solvent storage tanks. For these purposes, a variety of field investigations and studies were performed, which included installation of over 100 groundwater monitoring wells and piezometers at various depths, soil logging and analyses during well and piezometer installation, chemical analysis of groundwater, pump tests, and slug tests. Continuous water level monitoring at three selected wells using automatic data-logger and manual measuring at other wells were also conducted. Based on analyses of the various investigations and tests, a number of factors were identified to explain the distribution of the hydrocarbon contaminants and hydrogeochemical parameters. These factors include indigenous biodegradation, hydrostratigraphy, preliminary pump-and-treat remedy, recharge by rainfall, and subsequent water level fluctuation. The permeable sandy layer, in which the mean water table elevation is maintained, provided a dominant pathway for contaminant transport. The preliminary pump-and-treat action accelerated the movement of the hydrocarbon contaminants and affected the redox evolution pattern. Seasonal recharge by rain, together with indigenous biodegradation, played an important role in the natural attenuation of the petroleum hydrocarbons via mixing/dilution and biodegradation. The water level fluctuations redistributed the hydrocarbon contaminants by partitioning them into the soil and groundwater. The identified factors are not independent but closely inter-correlated.

A case of xanthoma of the liver in a 61-year-old Korean woman with multiple myeloma, hyperlipidemia and xanthoma of the skin is described. Microscopically, the liver showed a multiple xanthomatous collection of foamy histiocytes as well as diffuse sinusoidal infiltration of the foam cells. This hepatic accumulation of foam cells seems to be related to hyperlipidemia of the patient. The mechanism of hyperlipidemia in multiple myeloma is discussed.