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This work utilizes EIS to elucidate the impact of catalyst-ionomer interactions and cathode hydroxide ion transport resistance (RCL,OH-) on cell voltage and product selectivity for the electrochemical conversion of CO to ethylene. When using the same Cu catalyst and a Nafion ionomer, varying ink dispersion and electrode deposition methods results in a change of 2 orders of magnitude for RCL,OH- and ca. a 25% change in electrode porosity. Decreasing RCL,OH- results in improved ethylene Faradaic efficiency (FE), up to â¼57%, decrease in hydrogen FE, by â¼36%, and reduction in cell voltage by up to 1 V at 700 mA/cm2. Through the optimization of electrode fabrication conditions, we achieve a maximum of 48% ethylene with >90% FE for non-hydrogen products in a 25 cm2 membrane electrode assembly at 700 mA/cm2 and <3 V. Additionally, the implications of optimizing RCL,OH- is translated to other material requirements, such as anode porosity. We find that the best performing electrodes use ink dispersion and deposition techniques that project well into roll-to-roll processes, demonstrating the scalability of the optimized process.
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The electrochemical reduction of carbon dioxide to formic acid is a promising pathway to improve CO2 utilization and has potential applications as a hydrogen storage medium. In this work, a zero-gap membrane electrode assembly architecture is developed for the direct electrochemical synthesis of formic acid from carbon dioxide. The key technological advancement is a perforated cation exchange membrane, which, when utilized in a forward bias bipolar membrane configuration, allows formic acid generated at the membrane interface to exit through the anode flow field at concentrations up to 0.25 M. Having no additional interlayer components between the anode and cathode this concept is positioned to leverage currently available materials and stack designs ubiquitous in fuel cell and H2 electrolysis, enabling a more rapid transition to scale and commercialization. The perforated cation exchange membrane configuration can achieve >75% Faradaic efficiency to formic acid at <2 V and 300 mA/cm2 in a 25 cm2 cell. More critically, a 55-hour stability test at 200 mA/cm2 shows stable Faradaic efficiency and cell voltage. Technoeconomic analysis is utilized to illustrate a path towards achieving cost parity with current formic acid production methods.
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BACKGROUND: Shoulder arthroplasty has had increasing global demand, technical development, and research interest in the past few decades, with the publication of numerous articles. However, little is known about the characteristics and evaluation of these articles. Our objective was to study and analyze the top 100 cited articles in shoulder arthroplasty research. MATERIALS AND METHODS: Publications on shoulder arthroplasty from inception to 2022 were retrieved from the Web of Science. The top 100 publications were defined by the number of citations, and their characteristics were recorded and analyzed. A visualized study of the articles was performed using VOSviewer software. RESULTS: The top 100 cited articles were published between 1981 and 2018, with the 2000s the most productive decade. Citations per article ranged from 103 to 822. The countries with the most articles were the United States followed by France and Switzerland. Most of the articles were level III evidence. The keywords for the articles were primarily in 5 clusters: infection, fracture, osteoarthritis, perioperative complications, and prosthetic design. CONCLUSIONS: The characteristics of influential articles on shoulder arthroplasty were thoroughly analyzed. Most studies focused on surgical techniques and perioperative complications with a relatively low level of evidence.
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Artroplastía de Reemplazo de Hombro , Fracturas Óseas , Estados Unidos , Humanos , Bibliometría , Artroplastia , FranciaRESUMEN
INTRODUCTION: Local steroid injection (LSI) in the carpal tunnel is a mainstay of conservative treatment in patients with carpal tunnel syndrome (CTS). Currently, clinicians generally perform a conventional proximal approach (PA) or novel distal approach (DA) for LSI. Recent systematic reviews comparing the two injection methods are lacking. This systematic review and meta-analysis aimed to assess whether LSI using the DA was superior to PA in treating patients with CTS. METHODS: Databases including Pubmed, Embase, and the Cochrane library were searched up to 30 May 2022 to identify relevant randomized controlled trials (RCTs) comparing the DA with the PA steroid injection in patients with CTS. The outcomes mainly included Boston Carpal Tunnel Questionnaire Symptom Severity Scale (BCTQs) and Functional Status Scale (BCTQf), visual analog scores (VAS), electrophysiological outcomes, pain of injection, duration of injection, or adverse events. RESULTS: Five RCTs involving 339 patients were identified. Pooled analysis showed that the DA group took less time [mean difference (MD) -19.91; 95% CI -34.48 to -5.35; P = 0.007] and acquired better sensory nerve action potential amplitude [standardized mean difference (SMD) -0.37; 95% CI -0.62 to -0.11; P = 0.005]. The two groups were not significantly different in terms of BCTQs and BCTQf, VAS, other electrophysiological outcomes, pain of injection, or adverse events (P > 0.05). CONCLUSION: Although providing similar improvement in pain relief or function improvement, the distal approach is superior to the proximal approach in terms of timing, without increasing other side effects. Further high-quality randomized studies are required to confirm these results.
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Background: G-protein signaling modulator 2 (GPSM2) maintains cell polarization and regulates the cell cycle. Recent studies have shown that it is highly expressed in various tumors, but its pan-cancer analysis has not been reported. Methods: First, we analyzed the differential GPSM2 expression in normal and cancer tissues by the Cancer Genome Atlas (TCGA), Genotype-Tissue Expression (GTEx) and Human Protein Atlas databases and investigated its expression effect on the survival of cancer patients by gene expression profiling interactive analysis 2 (GEPIA2). Second, we analyzed the GPSM2 phosphorylation level using the clinical proteomic tumor analysis consortium dataset. In addition, we investigated GPSM2 gene mutations in human tumor specimens and the impact of gene mutations on patient survival. Finally, we analyzed the relationship between GPSM2 expression and cellular immune infiltration through the TIMER 2.0 database. Meanwhile, the possible signaling pathway of the gene was analyzed by the Gene Ontology (GO)| Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway to explore its potential mechanism. Results: GPSM2 is overexpressed in most cancers, which leads to reduced overall survival (OS) and disease-free survival in patients. The results of phosphorylation analysis suggest that tumor development involves a complex GPSM2 phosphorylation process. We identified GPSM2 mutation loci with the highest frequency of mutations in uterine corpus endometrial carcinoma (UCEC), and this mutation increased progression-free survival and overall survival in uterine corpus endometrial carcinoma patients. Finally, we found that the role of GPSM2 in tumors may be associated with cellular immune infiltration. Gene Ontology|KEGG pathway analysis showed that the enrichment pathways were mainly "mitotic nuclear division," "chromosome segregation," and "spindle." Conclusions: Our pan-cancer analysis provides a comprehensive overview of the oncogenic roles and potential mechanisms of GPSM2 in multiple human cancers.
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Nanoparticles are an important class of materials that exhibit special properties arising from their high surface area-to-volume ratio. Scanning transmission electron microscopy (STEM) has played an important role in nanoparticle characterization, owing to its high spatial resolution, which allows direct visualization of composition and morphology with atomic precision. This typically comes at the cost of sample size, potentially limiting the accuracy and relevance of STEM results, as well as the ability to meaningfully track changes in properties that vary spatially. In this work, automated STEM data acquisition and analysis techniques are employed that enable physical and compositional properties of nanoparticles to be obtained at high resolution over length scales on the order of microns. This is demonstrated by studying the localized effects of potential cycling on electrocatalyst degradation across proton exchange membrane fuel cell cathodes. In contrast to conventional, manual STEM measurements, which produce particle size distributions representing hundreds of particles, these high-throughput automated methods capture tens of thousands of particles and enable nanoparticle size, number density, and composition to be measured as a function of position within the cathode. Comparing the properties of pristine and degraded fuel cells provides statistically robust evidence for the inhomogeneous nature of catalyst degradation across electrodes. These results demonstrate how high-throughput automated STEM techniques can be utilized to investigate local phenomena occurring in nanoparticle systems employed in practical devices.
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In this study, we demonstrate three-dimensional (3D) hollow nanosphere electrocatalysts for CO2 conversion into formate with excellent H-Cell performance and industrially-relevant current density in a 25 cm2 membrane electrode assembly electrolyzer device. Varying calcination temperature maximized formate production via optimizing the crystallinity and particle size of the constituent SnO2 nanoparticles. The best performing SnO2 nanosphere catalysts contained ~ 7.5 nm nanocrystals and produced 71-81% formate Faradaic efficiency (FE) between -0.9 V and -1.3 V vs. the reversible hydrogen electrode (RHE) at a maximum formate partial current density of 73 ± 2 mA cmgeo-2 at -1.3 V vs. RHE. The higher performance of nanosphere catalysts over SnO2 nanoparticles and commercially-available catalyst could be ascribed to their initial structure providing higher electrochemical surface area and preventing extensive nanocrystal growth during CO2 reduction. Our results are among the highest performance reported for SnO2 electrocatalysts in aqueous H-cells. We observed an average 68 ± 8% FE over 35 h of operation with multiple on/off cycles. In situ Raman and time-dependent X-ray diffraction measurements identified metallic Sn as electrocatalytic active sites during long-term operation. Further evaluation in a 25 cm2 electrolyzer cell demonstrated impressive performance with a sustained current density of 500 mA cmgeo-2 and an average 75 ± 6% formate FE over 24 h of operation. Our results provide additional design concepts for boosting the performance of formate-producing catalysts.
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The recent surge in interest of proton exchange membrane fuel cells (PEMFCs) for heavy-duty vehicles increases the demand on the durability of oxygen reduction reaction electrocatalysts used in the fuel cell cathode. This prioritizes efforts aimed at understanding and subsequently controlling catalyst degradation. Identical-location scanning transmission electron microscopy (IL-STEM) is a powerful method that enables precise characterization of degradation processes in individual catalyst nanoparticles across various stages of cycling. Recreating the degradation processes that occur in PEMFC membrane electrode assemblies (MEAs) within the aqueous cell used for IL-STEM experiments is vital for generating an accurate understanding of these processes. In this work, we investigate the type and degree of catalyst degradation achieved by cycling in an aqueous cell compared to a PEMFC MEA. While significant degradation is observed in IL-STEM experiments performed on a traditional Pt catalyst using the standard accelerated stress test potential window (0.6-0.95 VRHE), degradation of a PtCo catalyst designed for heavy-duty vehicle use is very limited compared to that observed in MEAs. We therefore explore various experimental parameters such as temperature, acid type, acid concentration, ionomer content, and potential window to identify conditions that reproduce the degradation observed in MEAs. We find that by extending the cycling potential window to 0.4-1.0 VRHE in an electrolyte containing Pt ions, the degraded particle size distribution and alloy composition better match that observed in MEAs. In particular, these conditions increase the relative contribution of Ostwald ripening, which appears to play a more significant role in the degradation of larger alloy particles supported on high-surface-area carbons than coalescence. Results from this work highlight the potential for discrepancies between ex situ aqueous experiments and MEA tests. While different catalysts may require a unique modification to the AST protocol, strategies provided in this work enable future in situ and identical-location experiments that will play an important role in the development of robust catalysts for heavy-duty vehicle applications.
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Low cost and high-performing platinum group metal-free (PGM-free) cathodes have the potential to transform the economics of polymer electrolyte fuel cell (PEFC) commercialization. Significant advancements have been made recently in terms of PGM-free catalyst activity and stability. However, before PGM-free catalysts become viable in PEFCs, several technical challenges must be addressed including cathode's fabrication, ionomer integration, and transport losses. Here, we present an integrated optimization of cathode performance that was achieved by simultaneously optimizing the catalyst morphology and electrode structure for high power density. The chemically doped metal-organic framework derived Fe-N-C catalyst we used allows precise tuning of the particle size over a wide range, enabling this unique study. Our results demonstrate the careful interplay between the catalyst primary particle size and the polymer electrolyte ionomer integration. The primary particles must be sufficiently large to permit uniform ionomer thin films throughout the surrounding pores, but not so large as to impact intraparticle transport to the active sites. The content of ionomer must be carefully balanced between sufficient loading for the complete catalyst coverage and adequate proton conductivity, while not being excessive and inducing large oxygen transport losses and liquid water flooding. With the optimal 100 nm size catalyst and ionomer loading, we achieved a high power density of 410 mW/cm2 at a rated voltage and a peak power density of 610 mW/cm2 in an automotive-relevant operating condition.
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Stretchable high-dielectric-constant materials are crucial for electronic applications in emerging domains such as wearable computing and soft robotics. While previous efforts have shown promising materials architectures in the form of dielectric nano-/microinclusions embedded in stretchable matrices, the limited mechanical compliance of these materials significantly limits their practical application as soft energy-harvesting/storage transducers and actuators. Here, a class of liquid metal (LM)-elastomer nanocomposites is presented with elastic and dielectric properties that make them uniquely suited for applications in soft-matter engineering. In particular, the role of droplet size is examined and it is found that embedding an elastomer with a polydisperse distribution of nanoscale LM inclusions can enhance its electrical permittivity without significantly degrading its elastic compliance, stretchability, or dielectric breakdown strength. In contrast, elastomers embedded with microscale droplets exhibit similar improvements in permittivity but a dramatic reduction in breakdown strength. The unique enabling properties and practicality of LM-elastomer nanocomposites for use in soft machines and electronics is demonstrated through enhancements in performance of a dielectric elastomer actuator and energy-harvesting transducer.
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Previous studies have revealed that miR-142-5p serves a critical role in human cancer progression. However, the biological function of miR-142-5p in osteosarcoma (OS) development remains unclear. In the present study, the role of miR-142-5p in human OS HOS cells was determined, and the underlying mechanism involved was examined. Compared with the adjacent healthy tissues, the expression level of miR-142-5p was downregulated and the expression level of group XVI phospholipase A2 (PLA2G16) protein was upregulated in human OS tissues. The aforementioned results were also indicated in human OS HOS cells when compared with human fetal osteoblastic hFOB1.19 cells. Additionally, the results demonstrated that PLA2G16 was a direct target of miR-142-5p. miR-142-5p transfection upregulated the expression level of miR-142-5p and suppressed the expression level of PLA2G16 protein in HOS cells. MTT assays indicated a time-dependent decrease by miR-142-5p transfection in the proliferation of HOS cells. 5-bromo-2'-deoxyuridine incorporation assays confirmed that miR-142-5p transfection inhibited DNA synthesis in HOS cells. In addition, miR-142-5p transfection increased the Caspase-3 (CASP3) activity and apoptotic rate. Western blot analysis indicated that miR-142-5p transfection reduced BCL2, apoptosis regulator expression and upregulated the expression of CASP3 and BCL2 associated X, apoptosis regulator in HOS cells. Furthermore, miR-142-5p transfection decreased the expression levels of phosphorylated (p)-proto-oncogene, serine/threonine kinase, p-mitogen-activated protein kinase kinase, and p-extracellular signal-regulated kinase (ERK) 1/2 proteins in HOS cells. PLA2G16 overexpression restored the expression level of p-ERK 1/2 protein, which was reduced by miR-142-5p overexpression. MTT and CASP3 activity assays indicated that restoration of PLA2G16 reversed the tumour-suppressive role of miR-142-5p transfection in HOS cells. In conclusion, the results of the present study indicated that miR-142-5p suppressed proliferation and promoted apoptosis in human OS HOS cells by targeting PLA2G16 through ERK1/2 signaling pathway.
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Among extranodal NK/T-cell lymphoma of nasal type (NKTL), the extranasal variant (ENKTL) is known to have a worse prognosis with advanced clinical stage than the nasal variant of NKTL. However, detailed clinicopathological features of the localized extranasal disease have not been well documented in English literature. Here, we described the clinicopathological profiles of 14 patients with stage I ENKTL, including 7 in the skin, 5 in the gastrointestinal tract, and 2 in the central nervous system, highlighting the distinctiveness of the first. The 7 primary cutaneous (PCNKTL) cases were characterized by an older onset age (median, 76 versus 53 years, P=.012) and a more favorable clinical course (P=.041) compared with 17 patients with stages II-IV ENKTL that showed cutaneous involvement. The skin lesions in the PCNKTL group were distributed in the face or neck (n=4) and limbs (n=3) but not the trunk, which was most frequently affected (60%, P=.017) in the latter group. Furthermore, the stage I cutaneous disease showed a female predominance (male-female, 2:5 versus 7:0; P=.021) and a significantly more favorable survival compared with the noncutaneous stage I ENKTL (P=.037). These results suggest that PCNKTL constitute a distinct subgroup in the nasal-type lymphoma spectrum.
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Linfoma Extranodal de Células NK-T/patología , Linfoma Cutáneo de Células T/patología , Neoplasias Cutáneas/patología , Adulto , Edad de Inicio , Anciano , Anciano de 80 o más Años , Femenino , Herpesvirus Humano 4/aislamiento & purificación , Humanos , Estimación de Kaplan-Meier , Linfoma Extranodal de Células NK-T/mortalidad , Linfoma Extranodal de Células NK-T/terapia , Linfoma Extranodal de Células NK-T/virología , Linfoma Cutáneo de Células T/mortalidad , Linfoma Cutáneo de Células T/terapia , Linfoma Cutáneo de Células T/virología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Neoplasias Cutáneas/mortalidad , Neoplasias Cutáneas/terapia , Neoplasias Cutáneas/virología , Adulto JovenRESUMEN
AIMS: The central nervous system (CNS) is a rare primary site of non-Hodgkin lymphoma. Although direct invasion of nasal natural killer (NK)/T cell tumours into CNS is reported occasionally, primary CNS NK/T cell lymphoma is extremely rare, and the clinicopathological features of primary CNS NK/T cell lymphoma remain largely unknown. METHODS AND RESULTS: We identified four cases from our consultation files and analysed the clinicopathological features. Three were immunocompetent and one was immunosuppressed. There were three males and one female and their ages ranged from 21 to 77 years (median: 46 years). Radiotherapy was rendered for all patients, and methotrexate was administered to two patients. The overall survival was 4-29 months (median, 19 months) for the three immunocompetent patients. Neoplastic cells exhibited medium to large atypical nuclei. Angiocentric growth and necrosis were observed. The immunophenotype was typical of NK cell tumours: CD3ε, 100%; CD56, 67%; CD5, 50%; cytotoxic molecules, 100%; Epstein-Barr virus encoded small RNA (EBER), 100% and T cell receptor (TCR)-ß or γ, 0%. No TCR-gene rearrangements were detected. Reviewing 10 additional cases from the literature and comparing with extranasal NK/T cell lymphoma of the more frequent origins (skin or gastrointestinal tract), primary CNS NK/T cell lymphoma was diagnosed at an earlier stage without B symptoms but exhibited aggressive clinical behaviours. CONCLUSIONS: Although extremely rare, primary CNS NK/T cell lymphoma does occur and should always be included in the differential diagnosis and we should apply relevant markers routinely in conjunction with exploring the patient background. The accumulation of cases is indispensable to establish an effective treatment strategy for this rare and aggressive malignancy.
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Neoplasias del Sistema Nervioso Central/patología , Linfoma Extranodal de Células NK-T/patología , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
AIMS: Epstein-Barr virus-positive (EBV+ ) intestinal T/natural killer (NK) cell lymphoma (ITNKL) is an uncommon tumour with an extremely aggressive clinical behaviour. However, the clinicopathological characteristics of this tumour, including T cell receptor (TCR) phenotype and the patient's background, remain unknown. The aim of this study was to elucidate the detailed clinicopathological profile of EBV+ ITNKL. METHODS AND RESULTS: We enrolled 12 patients with EBV+ ITNKL without nasal involvement into the study. All patients were characterized by involvement of the small intestine with concurrent lesions of the large intestine in two patients. Seven patients (58%) had Lugano stages IIE/IV disease and eight (67%) were categorized as high-intermediate/high-risk according to the Prognostic Index for PTCL (PIT). Three patients (25%) with an age of onset of less than 50 years had chronic active EBV infection (CAEBV). Five CD56-positive patients (42%) had a poorer prognosis than those without CD56 expression (P = 0.008). NK cell-type lymphoma defined by the absence of any TCR expression or clonal TCR-γ rearrangement was found in six patients (50%). Interestingly, EBV+ intra-epithelial lymphocytosis was observed in one case with a background of CAEBV. CONCLUSIONS: This study is the first to shed light on the significant heterogeneity of EBV+ ITNKL and its relationship with CAEBV, especially in patients younger than 50 years of age. These observations will provide a guide for diagnostic and therapeutic approaches in routine practice.