Search

Investigation for novel catalytic materials is quite important for the development of fuel cell as well as hydrogen economy. In this study, platinum-cobalt (PtCo) bimetallic nanowires are prepared successfully by the centrifugal electrospinning technique and their potential as electrocatalyst is evaluated for proton exchange membrane fuel cell (PEMFC). The influences of operation conditions on nanowire morphology are studied, which include the rotation rate of spinneret, applied electric field, and nanowire composition. The electrochemical performance of the prepared nanowires is studied by performing the tests of cyclic voltammetry (CV) and linear sweep voltammetry (LSV) to characterize the electrochemical active surface area (ECSA) and oxygen reduction reaction (ORR) activity. The accelerated degradation tests (ADT) are also conducted to examine the durability of the nanowires. The membrane electrode assembly (MEA) using PtCo nanowires as cathode electrocatalyst is also made and its performance is compared with conventional MEA using Pt/C catalyst. It is found that under the situation of 1600 rpm of rotation rate, 12 cm of collection distance, and 13 kV of applied voltage, PtCo nanowires can be obtained with excellent morphology and the minimum mean diameter is 76 nm for the case of atomic ratio Pt:Co = 4:1. The corresponding ECSA is 41.2 m 2 g − 1 and the LSV and ADT results show the resultant PtCo nanowires exhibit better ORR activity and durability than Pt/C catalyst. [Display omitted] • PtCo nanowires are successfully prepared by centrifugal electrospinning technique. • Optimal parameters to produce PtCo nanowires are evaluated. • The produced PtCo nanowires present higher ORR activity than Pt/C. • The produced PtCo nanowires exhibit better durability in ECSA and ORR activity than Pt/C. [ABSTRACT FROM AUTHOR]

Owing to the early suffering age and the rising incidence of type 1 diabetes (T1D), the resulting male reproductive dysfunction and fertility decline have become a disturbing reality worldwide, with no effective strategy being available. Icariin (ICA), a flavonoid extracted from Herba Epimedium , has been proved its promising application in improving diabetes-related complications including diabetic nephropathy, endothelial dysfunction and erectile dysfunction. Ensuring the future reproductive health of children and adolescents with T1D is crucial to improve global fertility. However, its roles in the treatment of T1D-induced testicular dysfunction and the potential mechanisms remain elusive. The purpose of this present study was to investigate whether ICA ameliorates T1D-induced testicular dysfunction as well as its potential mechanisms. T1D murine model was established by intraperitoneal injection of STZ with or without treated with ICA for eleven weeks. Morphological, pathological and serological experiments were used to determine the efficacy of ICA on male reproductive function of T1D mice. Western blotting, Immunohistochemistry analysis, qRT-PCR and kit determination were performed to investigated the underlying mechanisms. We found that replenishment of ICA alleviated testicular damage, promoted testosterone production and spermatogenesis, ameliorated apoptosis and blood testis barrier impairment in streptozotocin-induced T1D mice. Functionally, ICA treatment triggered adenosine monophosphate protein kinase (AMPK) activation, which in turn inhibited the nuclear translocation of nuclear factor kappa B p65 (NF-κB p65) to reduce inflammatory responses in the testis and activated nuclear factor erythroid 2-related factor 2(Nrf2), thereby enhancing testicular antioxidant capacity. Further studies revealed that supplementation with the AMPK antagonist Compound C or depletion of Nrf2 weakened the beneficial effects of ICA on testicular dysfunction of T1D mice. Collectively, these results demonstrate the feasibility of ICA in the treatment of T1D-induced testicular dysfunction, and reveal the important role of AMPK-mediated Nrf2 activation and NF-κB p65 inhibition in ICA-associated testicular protection during T1D. [Display omitted] [ABSTRACT FROM AUTHOR]

Suturing is a crucial clinical skill for nurse practitioners (NPs), but the effectiveness of traditional training methods (e.g., physical suture kits combined with video content) is low. This study compared the effectiveness and usability of a mobile-based web app (MoWa) developed for NPs to learn simple suturing skills with those of traditional instructional video–based training. The MoWa system utilizes mobile devices to simulate hands-on suturing and provides learning guidance and feedback to support self-learning with a physical suturing kit. Fifty-four suturing novices (NPs) were recruited as participants, divided into an experimental group (EG: 28 participants) and a control group (CG: 26 participants), and instructed to self-learn for 3 weeks. Learning effectiveness and system usability were evaluated through a pretest and posttest. The EG exhibited significant improvements in learning outcomes, self-confidence, self-efficacy, and learning anxiety and expressed satisfaction with the MoWa system. Furthermore, the EG also considerably enhanced learning outcomes, self-efficacy, and learning anxiety compared to the CG, with no significant difference in self-confidence. The MoWa system combined with deliberate practice is an effective strategy for supporting suturing skills training. • App to support hands-on learning of simple suturing skills with real-time feedback • App improved learning performance of NPs and reduced their learning anxiety. • App plus practice can be an effective strategy to support suturing skills learning. [ABSTRACT FROM AUTHOR]

Abstract: A new artificial receptor 1 was developed, and its chromogenic and fluorogenic behaviors toward various metal ions were investigated. Receptor 1 shows exclusively responses toward Hg2+ and Cu2+ ions. It selectively senses Hg2+ and Cu2+ ions through two different color changes in aqueous solution (DMSO/H2O=4/1) and also distinguishes them from other metal ions. In addition, receptor 1 also exhibits pronounced enhancements of the fluorescence, which can visually be discernible by an orchid fluorescence in the presence of Hg2+ ions and a strong blue fluorescence in the presence of Cu2+ ions. [Copyright &y& Elsevier]

High-quality youth development programs can serve as relationship-rich spaces where youth develop a sense of belonging and meaningful connections with caring adults and peers. The pathways between strong relationships and youth's sense of belonging within these settings remains unexplored, particularly among PYD programs who serve youth from low-income communities. Therefore, this study examined the bidirectional pathways between developmental relationships with program peers and program staff and youth's sense of belonging. The study included 194 youth (ages 8–17; 75% youth of color; 46% female) who participated in a program designed to provide youth living in low-income households with trusting relationships and greater access to year-round enrichment opportunities. Utilizing survey data across three time points, findings show how youth's sense of belonging and developmental relationships with program peers led to stronger developmental relationships with program staff over time. Findings highlight important implications for the role of program peers within positive youth development programs. [ABSTRACT FROM AUTHOR]

To examine the extent to which the urologist performing biopsy contributes to variation in prostate cancer detection during fusion-guided prostate biopsy. All men in the Michigan Urological Surgery Improvement Collaborative (MUSIC) clinical registry who underwent fusion biopsy at Michigan Medicine from August 2017 to March 2019 were included. The primary outcomes were clinically significant cancer detection rate (defined as Gleason Grade ≥2) in targeted cores and clinically significant cancer detection on targeted cores stratified by PI-RADS score. Bivariate and multivariable logistic regression analyses were performed. A total of 1133 fusion biopsies performed by 5 providers were included. When adjusting for patient age, PSA, race, family history, prostate volume, clinical stage, and PI-RADS score, there was no significant difference in targeted clinically significant cancer detection rates across providers (range = 38.5%-46.9%, adjusted P -value =.575). Clinically significant cancer detection rates ranged from 11.1% to 16.7% in PI-RADS 3 (unadjusted P =.838), from 24.6% to 43.4% in PI-RADS 4 (adjusted P =.003), and from 69.4% to 78.8% in PI-RADS 5 (adjusted P =.766) lesions. There was a statistically significant difference in clinically significant prostate cancer detection in PI-RADS 4 lesions across providers. These findings suggest that even among experienced providers, variation at the urologist level may contribute to differences in clinically significant cancer detection rates within PI-RADS 4 lesions. However, the relative impact of biopsy technique, radiologist interpretation, and MR acquisition protocol requires further study. [ABSTRACT FROM AUTHOR]

Abstract: Electrical properties of RF sputtered ZrO2 memory thin films were investigated in this study. The device with structure Al/ZrO2/Pt shows a reproducible resistive switching behavior traced over 100 times at room temperature. Moreover, by using various top electrodes, such as Pt, Cu, Ni, Ag, Ti, and even W-probe, the resistive switching phenomenon can be observed in ZrO2-based memory with Pt bottom electrode, indicating that the ZrO2 bulk dominates the resistive switching. The bias polarity dependent resistive switching behavior is demonstrated in the Ti/ZrO2/Pt device, which might be due to interface reaction between Ti and ZrO2 film. The resistance value of high conductive state in the Ti/ZrO2/Pt device decreases with increasing current compliance implying the possibility for multi-bit storage. Besides, the Ti/ZrO2/Pt device can be operated over 2000 resistive switching cycles at 85 °C by sweeping DC voltage, and the two memory states demonstrate good stability under read voltage stress at room temperature and 85 °C. The write-read-erase-read operations can be over 103 cycles at 85 °C. No data loss is found upon successive readout before and after performing 103 endurance cycles at 85 °C. According to above experimental results, the ZrO2 thin film has high potential for nonvolatile memory application. [Copyright &y& Elsevier]

Decellularized porcine small intestinal submucosa (SIS) has shown promising therapeutic efficacy as a functional wound dressing. Nevertheless, its limited anti-oxidative and immunomodulatory capacities have restricted its application for the treatment of complex skin wounds. Herein, epigallocatechin gallate (EGCG), a polyphenolic compound, was employed for the modification of the SIS to overcome such shortcomings. The EGCG-modified SIS (E-SIS) has shown excellent biocompatibility and improved hydrophilicity for cell adhesion. Notably, in vitro studies showed that the E-SIS could effectively alleviate oxidative stress and facilitate the M1-to-M2 phenotype transition of macrophages, thereby creating a favorable immune microenvironment for cell proliferation, migration, collagen synthesis as well as angiogenesis. A full-thickness skin defect model, combined with macrophage depletion, has further confirmed that the E-SIS could accelerate skin wound repair through immunomodulation in vivo. This suggested that the EGCG modification could provide a facile yet effective method to broaden the applications of the SIS for skin wound management. [ABSTRACT FROM AUTHOR]

This paper proposes high efficiency semitransparent organic solar cells (OSCs) with good color perception and good color rendering using blade coating technique. We investigate four different polymer blends and first fabricate small area devices with active area of 0.04 cm 2 , followed by large area devices with active area of 10.8 cm 2 . Two of the polymer blends, 2,6-Bis(trimethyltin)-4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b:4,5-b']dithiophene:6,6-phenyl C71-butyric acid methyl ester (PBDTTT-CT:PC 71 BM) and poly[4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b;4,5-b′] dithiophene-2,6-diyl-alt-(4-(2-ethylhexyl)-3-fluorothieno[3,4- b ]thiophene-)-2-carboxylate-2-6-diyl)]:PC 71 BM (PBDTTT-EFT:PC 71 BM) show promising results. For small area devices, semitransparent PBDTTT-CT:PC 71 BM and semitransparent PBDTTT-EFT:PC 71 BM achieve a power conversion efficiency (PCE) of 5.2% (opaque PCE = 7.5%) and 5.6% (opaque PCE = 9.4%) respectively. For large area devices, they are found to produce a PCE of 3.8% (opaque PCE = 4.2%) and 5.3% (opaque PCE = 5.9%) respectively. Based on the CIE 1931 chromaticity diagram, semitransparent PBDTTT-CT:PC 71 BM and semitransparent PBDTTT-EFT:PC 71 BM are located very close to the standard illuminant D65, indicating good color perception. As for color rendering, they demonstrate high color rendering index (CRI) of 95.4 and 87.1 respectively. These combined high performances indicate high-quality transmitted light, which is suitable for window application. [ABSTRACT FROM AUTHOR]

In this paper, we present a framework of orientation analysis for rotated human face detection. A novel orientation histogram is constructed for statistical analysis of face images, which can show a proper symmetry with respect to the orientation of the principal axis and a local peak at its orthogonal orientation. By analyzing the orientation histogram, we can easily find the principal axis'' orientation of the rotated face. Then an upright frontal face detector based on orientation analysis and other knowledge is designed to verify the given face. The experimental results illustrate the effectiveness of our framework. [Copyright &y& Elsevier]