Improving Granulosa Cell Function in Premature Ovarian Failure with Umbilical Cord Mesenchymal Stromal Cell Exosome-Derived hsa_circ_0002021.

BACKGROUND: The therapeutic potential of exosomes from human umbilical cord mesenchymal stem cells (HUMSCs-Exo) for delivering specific circular RNAs (circRNAs) in treating premature ovarian failure (POF) is not well understood. This study aimed to explore the efficacy of HUMSCs-Exo in delivering hsa_circ_0002021 for POF treatment, focusing on its effects on granulosa cell (GC) senescence and ovarian function. METHODS: Bioinformatic analysis was conducted on circRNA profiles using the GSE97193 dataset from GEO, targeting granulosa cells from varied age groups. To simulate granulosa cell senescence, KGN cells were treated with cyclophosphamide (CTX). HUMSCs were transfected with pcDNA 3.1 vectors to overexpress hsa_circ_0002021, and the HUMSCs-Exo secreted were isolated. These exosomes were characterized by transmission electron microscopy (TEM) and Western blotting to confirm exosomal markers CD9 and CD63. Co-culture of these exosomes with CTX-treated KGN cells was performed to assess ß-galactosidase activity, oxidative stress markers, ROS levels, and apoptosis via flow cytometry. Interaction between hsa_circ_0002021, microRNA-125a-5p (miR-125a-5p), and cyclin-dependent kinase 6 (CDK6) was investigated using dual-luciferase assays and RNA immunoprecipitation (RIP). A POF mouse model was induced with CTX, treated with HUMSCs-Exo, and analyzed histologically and via immunofluorescence staining. Gene expression was quantified using RT-qPCR and Western blot. RESULTS: hsa_circ_0002021 was under expressed in both in vivo and in vitro POF models and was effectively delivered by HUMSCs-Exo to KGN cells, showing a capability to reduce GC senescence. Overexpression of hsa_circ_0002021 in HUMSCs-Exo significantly enhanced these anti-senescence effects. This circRNA acts as a competitive adsorbent of miR-125a-5p, regulating CDK6 expression, which is crucial in modulating cell cycle and apoptosis. Enhanced expression of hsa_circ_0002021 in HUMSCs-Exo ameliorated GC senescence in vitro and improved ovarian function in POF models by modulating oxidative stress and cellular senescence markers. CONCLUSION: This study confirms that hsa_circ_0002021, when delivered through HUMSCs-Exo, can significantly mitigate GC senescence and restore ovarian function in POF models. These findings provide new insights into the molecular mechanisms of POF and highlight the therapeutic potential of circRNA-enriched exosomes in treating ovarian aging and dysfunction.

Iron-Cobalt Phosphide Encapsulated in a N-Doped Carbon Framework as a Promising Low-Cost Oxygen Reduction Electrocatalyst for Zinc-Air Batteries.

The oxygen reduction reaction (ORR) plays a vital role in many next-generation electrochemical energy conversion and storage devices, motivating the search for low-cost ORR electrocatalysts possessing high activity and excellent durability. In this work, we demonstrate that iron-cobalt phosphide (FeCoP) nanoparticles encapsulated in a N-doped carbon framework (FeCoP@NC) represent a very promising catalyst for the ORR in alkaline media. The core-shell structured FeCoP@NC catalyst offered outstanding ORR activity with a half-wave potential (E1/2) of 0.86 V vs reversible hydrogen electrode (RHE) and excellent stability in a 0.1 M KOH electrolyte, outperforming commercial Pt/C and many recently reported noble-metal-free ORR electrocatalysts. The superiority of FeCoP@NC as an ORR electrocatalyst relative to Pt/C was further verified in prototype zinc-air batteries (ZABs), with the aqueous and flexible ZABs prepared using FeCoP@NC offering excellent stability, impressive open circuit voltages (1.56 and 1.44 V, respectively), and high maximum power densities (183.5 and 69.7 mW cm-2, respectively). Density functional theory calculations revealed that encapsulating FeCoP nanoparticles in N-doped carbon shells resulted in favorable electron penetration effects, which synergistically regulated the adsorption/desorption of ORR intermediates for optimal ORR performance while also boosting the electronic conductivity. Our findings offer valuable new insights for rational design of transition metal phosphide-based catalysts for the ORR and other electrochemical applications.

Space-Confined Growth of Ultrathin P-Type GeTe Nanosheets for Broadband Photodetectors.

As p-type phase-change degenerate semiconductors, crystalline and amorphous germanium telluride (GeTe) exhibit metallic and semiconducting properties, respectively. However, the massive structural defects and strong interface scattering in amorphous GeTe films significantly reduce their performance. In this work, two-dimensional (2D) p-type GeTe nanosheets are synthesized via a specially designed space-confined chemical vapor deposition (CVD) method, with the thickness of the GeTe nanosheets reduced to 1.9 nm. The space-confined CVD method improves the crystallinity of ultrathin GeTe by lowering the partial pressure of the reactant gas, resulting in GeTe nanosheets with excellent p-type semiconductor properties, such as a satisfactory on/off ratio of 105 . Temperature-dependent electrical measurements demonstrate that variable-range hopping and optical-phonon-assisted hopping mechanisms dominate transport behavior at low and high temperatures, respectively. GeTe devices exhibit significantly high responsivity (6589 and 2.2 A W-1 at 633 and 980 nm, respectively) and detectivity (1.67 × 1011 and 1.3 × 108 Jones at 633 and 980 nm, respectively), making them feasible for broadband photodetectors in the visible to near-infrared range. Furthermore, the fabricated GeTe/WS2 diode exhibits a rectification ratio of 103 at zero gate voltage. These satisfactory p-type semiconductor properties demonstrate that ultrathin GeTe exhibits enormous potential for applications in optoelectronic interconnection circuits.

LIPUS regulates the progression of knee osteoarthritis in mice through primary cilia-mediated TRPV4 channels.

Osteoarthritis (OA) is a common disease in middle-aged and elderly people. An imbalance in calcium ion homeostasis will contribute to chondrocyte apoptosis and ultimately lead to the progression of OA. Transient receptor potential channel 4 (TRPV4) is involved in the regulation of intracellular calcium homeostasis. TRPV4 is expressed in primary cilia, which can sense mechanical stimuli from outside the cell, and its abnormal expression is closely related to the development of OA. Low-intensity pulsed ultrasound (LIPUS) can alleviate chondrocyte apoptosis while the exact mechanism is unclear. In this project, with the aim of revealing the mechanism of action of LIPUS, we proposed to use OA chondrocytes and animal models, LIPUS intervention, inhibition of primary cilia, use TRPV4 inhibitors or TRPV4 agonist, and use Immunofluorescence (IF), Immunohistochemistry (IHC), Western Blot (WB), Quantitative Real-time PCR (QP) to detect the expression of cartilage synthetic matrix and endoplasmic reticulum stress markers. The results revealed that LIPUS altered primary cilia expression, promoted synthetic matrix metabolism in articular chondrocytes and was associated with primary cilia. In addition, LIPUS exerted a active effect on OA by activating TRPV4, inducing calcium inward flow, and facilitating the entry of NF-κB into the nucleus to regulate synthetic matrix gene transcription. Inhibition of TRPV4 altered primary cilia expression in response to LIPUS stimulation, and knockdown of primary cilia similarly inhibited TRPV4 function. These results suggest that LIPUS mediates TRPV4 channels through primary cilia to regulate the process of knee osteoarthritis in mice.

Defect Engineering of 2D Semiconductors for Dual Control of Emission and Carrier Polarity.

2D transition metal dichalcogenides (TMDCs) are considered as promising materials in post-Moore technology. However, the low photoluminescence quantum yields (PLQY) and single carrier polarity due to the inevitable defects during material preparation are great obstacles to their practical applications. Here, an extraordinary defect engineering strategy is reported based on first-principles calculations and realize it experimentally on WS2 monolayers by doping with IIIA atoms. The doped samples with large sizes possess both giant PLQY enhancement and effective carrier polarity modulation. Surprisingly, the high PL emission maintained even after one year under ambient environment. Moreover, the constructed p-n homojunctions shows high rectification ratio (≈2200), ultrafast response times and excellent stability. Meanwhile, the doping strategy is universally applicable to other TMDCs and dopants. This smart defect engineering strategy not only provides a general scheme to eliminate the negative influence of defects, but also utilize them to achieve desired optoelectronic properties for multifunctional applications.

Lymph node ratio independently associated with postoperative thyroglobulin levels in papillary thyroid cancer.

OBJECTIVES: To investigate the impact of the lymph node ratio (LNR) on postoperative thyroglobulin (Tg) levels in patients with papillary thyroid carcinoma (PTC). PATIENTS AND METHODS: This was a retrospective, cohort study. The association between clinicopathological variables and postoperative unstimulated Tg (uTg) levels, preablative-stimulated Tg (sTg) levels, and postablative unstimulated Tg levels was analysed. RESULTS: A total of 300 patients with PTC were identified. Multivariate logistic analysis showed that M classification (odds ratio [OR], 2.33; 95% confidence interval [CI], 1.62-3.34), and postoperative thyroid-stimulating hormone levels (OR, 1.01; 95% CI, 1.01-1.02) were independently associated with postoperative uTg levels. One hundred and sixteen patients underwent radioactive iodine (RAI) therapy. Multivariate analysis showed that LNR in the central neck (OR, 1.24; 95% CI, 1.02-1.51), LNR in the lateral neck (OR, 1.73; 95% CI, 1.09-2.77), RAI dose (OR, 1.43; 95% CI, 1.21-1.69), and M classification (OR, 1.79; 95% CI, 1.22-2.61) were independently associated with preablative sTg levels. Tumour size (OR, 1.01; 95% CI, 1.00-1.01), LNR in the central neck (OR, 1.28; 95% CI, 1.08-1.51), LNR in the lateral neck (OR, 1.66; 95% CI, 1.10-2.49), RAI dose (OR, 1.54; 95% CI, 1.34-1.79), and M classification (OR, 1.56; 95% CI, 1.12-2.19) were also independently associated with postablative uTg levels. CONCLUSION: LNR was independently associated with postoperative Tg levels in patients with PTC. Patients with high LNR were more likely to have incomplete biochemical responses after surgery.

Ubiquitin Ligase Nrdp1 Controls Autophagy-Associated Acrosome Biogenesis and Mitochondrial Arrangement during Spermiogenesis.

Autophagy is critical to acrosome biogenesis and mitochondrial quality control, but the underlying mechanisms remain unclear. The ubiquitin ligase Nrdp1/RNF41 promotes ubiquitination of the mitophagy-associated Parkin and interacts with the pro-autophagic protein SIP/CacyBP. Here, we report that global deletion of Nrdp1 leads to formation of the round-headed sperm and male infertility by disrupting autophagy. Quantitative proteome analyses demonstrated that the expression of many proteins associated with mitochondria, lysosomes, and acrosomes was dysregulated in either spermatids or sperm of the Nrdp1-deficient mice. Deletion of Nrdp1 increased the levels of Parkin but decreased the levels of SIP, the mitochondrial fission protein Drp1 and the mitochondrial protein Tim23 in sperm, accompanied by the inhibition of autophagy, the impairment of acrosome biogenesis and the disruption of mitochondrial arrangement in sperm. Thus, our results uncover an essential role of Nrdp1 in spermiogenesis and male fertility by promoting autophagy, providing important clues to cope with the related male reproductive diseases.

Lymph node ratio as a tool to stratify patients with N1b papillary thyroid cancer.

BACKGROUND: The prognostic significance of lymph node ratio (LNR) in N1b papillary thyroid cancer is unclear. Therefore, the impact of LNR on disease-specific mortality (DSM) and overall survival (OS) in patients with N1b papillary thyroid cancer (PTC) needs to be defined. METHODS: We used the Surveillance, Epidemiology, and End Results (SEER) database of patients who had undergone thyroidectomy and lymph node dissection. Factors associated with DSM and OS were analyzed and identified using univariate and multivariate Cox proportional risk models. X-tile software was used to find the best cutoff value of LNR. Kaplan-Meier estimates for DSM were plotted for LNR and were compared with the log-rank test. The ROC curve evaluated the validity of the model. RESULTS: A total of 3223 patients with N1b PTC were identified in the SEER database between 1975 and 2019. The best cutoff value for LNR was 0.6. The multivariate Cox proportional risk model showed that age, race, T3/T4 classification, distant metastasis, extent of surgery, number of metastatic lymph nodes, and LNR > 0.6 were independent risk factors for DSM (all p < 0.05). Age, sex, T4 classification, distant metastasis, extent of surgery, and LNR > 0.6 were independent risk factors for OS (all p < 0.05). The Kaplan-Meier method plotted a cumulative risk curve and showed that patients with LNR > 0.6 had a significantly higher risk of DSM than patients with LNR ≤ 0.6 (p = 0.002). CONCLUSION: LNR was a powerful predictor of DSM and OS in N1b PTC patients. LNR could be a useful tool for the stratification of PTC patients with lateral neck metastases.

Sodium Tartrate-Assisted Synthesis of High-Purity NiFe2O4 Nano-Microrods Supported by Porous Ketjenblack Carbon for Efficient Alkaline Oxygen Evolution.

Herein, a simple two-step synthetic method was developed for the synthesis of NiFe2O4 nano-microrods supported on Ketjenblack carbon (NiFe2O4/KB). A sodium tartrate-assisted hydrothermal method was employed for the synthesis of a NiFe-MOF/KB precursor, which was then pyrolyzed under N2 at 500 °C to yield NiFe2O4/KB. Benefiting from the presence of high-valence Ni3+ and Fe3+, high conductivity, and a large electrochemically active surface area, NiFe2O4/KB delivered outstanding OER electrocatalytic performance under alkaline conditions, including a very low overpotential of 258 mV (vs RHE) at 10 mA cm-2, a small Tafel slope of 43.01 mV dec-1, and excellent durability in 1.0 M KOH. Density functional theory calculations verified the superior alkaline OER electrocatalytic activity of NiFe2O4 to IrO2. While both catalysts possessed a similar metallic ground state, NiFe2O4 offered a lower energy barrier in the rate-determining OER step (*OOH → O2) compared to IrO2, resulting in faster OER kinetics.

A universal growth method for high-quality phase-engineered germanium chalcogenide nanosheets.

Low-dimensional group IV-VI metal chalcogenide-based semiconductors hold great promise for opto-electronic device applications owing to their diverse crystalline phases and intriguing properties related to thermoelectric and ferroelectric effects. Herein, we demonstrate a universal chemical vapor deposition (CVD) growth method to synthesize stable germanium chalcogenide-based (GeS, GeS2, GeSe, GeSe2) nanosheets, which increases the library of the p-type semiconductor. The phase transition between different crystalline polytypes can be deterministically controlled by hydrogen concentration in the reaction chamber. Structural characterization and synthesis experiments identify the behavior, where the higher hydrogen concentration promotes the transiton from germanium dichalcogenides to germanium monochalcogenides. The angle-polarized and temperature-dependent Raman spectra demonstrate the strong interlayer coupling and lattice orientation. Based on the optimized growth scheme and systematic comparison of electrical properties, GeSe nanosheet photodetectors were demonstrated, which exhibit superior device performance on SiO2/Si and HfO2/Si substrate with a high photoresponsivity up to 104 A W-1, fast response time less than 15 ms, and high mobility of 3.2 cm2 V-1 s-1, which is comparable to the mechanically exfoliated crystals. Our results manifest the hydrogen-mediated deposition strategy as a facile control knob to engineer crystalline phases of germanium chalcogenides for high performance optoelectronic devices.

Nanostructure Engineering and Electronic Modulation of a PtNi Alloy Catalyst for Enhanced Oxygen Reduction Electrocatalysis in Zinc-Air Batteries.

PtNi nanoalloys have demonstrated electrocatalysis superior to that of benchmark Pt/C catalysts for the oxygen reduction reaction (ORR), yet the underlying mechanisms remain underexplored. Herein, a PtNi/NC catalyst comprising PtNi nanoparticles (∼5.2 nm in size) dispersed on N-doped carbon frameworks was prepared using a simple pyrolysis strategy. Benefiting from the individual components and a hierarchical structure, the PtNi/NC catalyst exhibited outstanding ORR activity and stability (E1/2 = 0.82 V vs RHE and 8 mV negative shift after 20000 cycles), outperforming a commercial 20 wt % Pt/C catalyst (E1/2 = 0.81 V and 32 mV negative shift). A prototype zinc-air battery constructed using PtNi/NC as the air electrode catalyst achieved highly enhanced electrochemical performance, outperforming a battery constructed using Pt/C as the ORR catalyst. Density functional theory calculations revealed that the improved ORR activity of the PtNi nanoalloys originated from charge redistribution with a suitable metal d-band center to promote the formation of the ORR intermediates.

Design of new drugs for medullary thyroid carcinoma.

Medullary thyroid carcinoma (MTC) is one of the common malignant endocrine tumors, which seriously affects human health. Although surgical resection offers a potentially curative therapeutic option to some MTC patients, most patients do not benefit from it due to the difficulty to access the tumors and tumor metastasis. The survival rate of MTC patients has improved with the recent advances in the research, which has improved our understanding of the molecular mechanism underlying MTC and enabled the development and approval of novel targeted drugs. In this article, we reviewed the molecular mechanisms related to MTC progression and the principle for the design of molecular targeted drugs, and proposed some future directions for prospective studies exploring targeted drugs for MTC.

Disruptive Strategy To Fabricate Three-Dimensional Ultrawide Interlayer Porous Carbon Framework-Supported Prussian Blue Nanocubes: A Carrier for NiFe-Layered Double-Hydroxide toward Oxygen Evolution.

We, for the first time, offer a unique and disruptive strategy to prepare N-doped three-dimensional porous carbon framework-supported well-defined Fe4[Fe(CN)6]3 nanocubes (indicated as PB@N-PCFs). The carbon frameworks hold an ultrawide interlayer spacing of 0.385-0.402 nm for the (002) planes of graphite and ultrahigh graphitization. Furthermore, PB@N-PCFs are used as a carrier to grow NiFe-layered-double-hydroxide nanosheet arrays (denoted as NiFe-LDH/PB@N-PCFs) in situ, where the interlayer spacing for the (002) planes of graphite can be expanded as high as 0.457 nm in the carbon frameworks. Moreover, NiFe-LDH/PB@N-PCFs shows excellent electrocatalytic performance toward oxygen evolution in terms of activity, kinetics, and durability, elegantly rivaling the state-of-the-art RuO2. More profoundly, after 3000 cycle cyclic voltammetry scans, NiFe-LDH/PB@N-PCFs still display far more desirable activity with respect to initial NiFe-LDH/PB@N-PCFs. We believe that the PB@N-PCFs and PB@N-PCFs-based composites with ultrahighly graphitized and large interlayer spacing N-PCFs can find more places in electrochemistry-related applications such as Na/K-ion batteries, electrocatalysis, and electrochemical sensors.

A Hybrid of the Fe4N-Fe Heterojunction Supported on N-Doped Carbon Nanobelts and Ketjen Black Carbon as a Robust High-Performance Electrocatalyst.

Herein, an extremely simple l-alanine-assisted pyrolysis method was proposed for the construction of a novel hierarchically porous hybrid of Fe4N-Fe supported on N-doped carbon nanobelts and Ketjen black carbon (denoted as Fe4N-Fe@N-C/N-KB). It has been found that the participation of l-alanine in pyrolysis can dramatically increase the total pyridinic-N/graphitic-N content in Fe4N-Fe@N-C/N-KB, which is peculiarly conducive to the enhancement of ORR performance. The in-site formation of the Fe4N-Fe heterojunction via the thermal reduction and decomposition of Fe3N as well as the introduction of cheap KB can significantly improve the ORR performance. As a result, the activity, durability, and methanol tolerance of this hybrid are comprehensively better than those of commercial 20 wt % Pt/C, promising future applications in practical devices. Density functional theory calculations disclose that the highly improved ORR activity of Fe4N-Fe@N-C/N-KB also benefits from the favorable electron penetration and excellent electronic conductivity between the Fe4N nanoparticles and the N-incorporated carbon frameworks.

Recent Advances in Self-Supported Semiconductor Heterojunction Nanoarrays as Efficient Photoanodes for Photoelectrochemical Water Splitting.

Growth of semiconductor heterojunction nanoarrays directly on conductive substrates represents a promising strategy toward high-performance photoelectrodes for photoelectrochemical (PEC) water splitting. By controlling the growth conditions, heterojunction nanoarrays with different morphologies and semiconductor components can be fabricated, resulting in greatly enhanced light-absorption properties, stabilities, and PEC activities. Herein, recent progress in the development of self-supported heterostructured semiconductor nanoarrays as efficient photoanode catalysts for water oxidation is reviewed. Synthetic methods for the fabrication of heterojunction nanoarrays with specific compositions and structures are first discussed, including templating methods, wet chemical syntheses, electrochemical approaches and chemical vapor deposition (CVD) methods. Then, various heterojunction nanoarrays that have been reported in recent years based on particular core semiconductor scaffolds (e.g., TiO2 , ZnO, WO3 , Fe2 O3 , etc.) are summarized, placing strong emphasis on the synergies generated at the interface between the semiconductor components that can favorably boost PEC water oxidation. Whilst strong progress has been made in recent years to enhance the visible-light responsiveness, photon-to-O2 conversion efficiency and stability of photoanodes based on heterojunction nanoarrays, further advancements in all these areas are needed for PEC water splitting to gain any traction alongside photovoltaic-electrochemical (PV-EC) systems as a viable and cost-effective route toward the hydrogen economy.

Lymph node ratio in lateral neck is an independent risk factor for recurrence-free survival in papillary thyroid cancer patients with positive lymph nodes.

BACKGROUND: The purpose of this study was to explore the impact of the lymph node ratio on prognosis in papillary thyroid cancer patients with lymph node metastasis. METHODS: Data from papillary thyroid cancer patients with positive nodes who were initially treated at our institution during 2015-2016 were analysed. Univariate and multivariate Cox proportional hazard models were adopted to predict prognostic factors. A receiver operating characteristic (ROC) curve was used to find the best cut-off value of the lymph node ratio (LNR). Kaplan-Meier curves were used to show the relationship between the LNR in the lateral neck and recurrence-free survival. RESULTS: The median follow-up time was 64.6 months, and recurrence occurred in 16 of 662 patients (2.27%). Univariate analysis showed that male sex, primary tumour size (>17 mm), visible extrathyroidal extension, LNR in the central neck (>0.5), LNR in the lateral neck (>0.10), and visible extranodal extension were significantly correlated with recurrence-free survival (RFS) (p < 0.05). Multivariate analysis using the Cox proportional hazards model showed that the LNR in the lateral neck was an independent risk factor for RFS (p = 0.039; HR 14.76). CONCLUSION: The LNR in the lateral neck was an independent risk factor for recurrence-free survival. For patients with a high lymph node ratio in the lateral neck, more frequent follow-up might be needed.

Electronic Tuning of Core-Shell CoNi Nanoalloy/N-Doped Few-Layer Graphene for Efficient Oxygen Electrocatalysis in Rechargeable Zinc-Air Batteries.

The discovery of highly efficient, durable, and affordable bifunctional ORR/OER electrocatalysts is of great significance for the commercialization of rechargeable metal-air batteries. Herein, we synthesized uniformly sized CoNi alloy nanoparticles encapsulated with N-doped few-layer graphene (N-FLG) sheets via pyrolysis of a CoNi dual metal-organic framework precursor. The developed CoNi/N-FLG catalyst exhibited excellent oxygen reduction activity (comparable to a commercial 20 wt % Pt/C catalyst) and outstanding oxygen evolution activity (superior to a commercial 20 wt % IrO2/C catalyst), thus enabling efficient bifunctional oxygen electrocatalysis and stability when applied in prototype rechargeable zinc-air batteries. The remarkable electrochemical properties of CoNi/N-FLG originate from its unique core-shell structure and favorable electron penetration effects, thereby optimizing the adsorption/desorption strengths of intermediates formed during the oxygen reduction and oxygen evolution reactions.

Experimental and Theoretical Insights into Enhanced Hydrogen Evolution over PtCo Nanoalloys Anchored on a Nitrogen-Doped Carbon Matrix.

The identification of synergistic effect of Pt-based alloys on hydrogen evolution reaction (HER) requires a combination of experimental studies and theoretical calculations. Here, we present the construction of uniform PtCo nanoparticles grown on N-doped carbon frameworks via pyrolyzing Pt and Co ions adsorbed polyaniline, whereby the nanostructure of the nanoalloys can be effectively tuned by controlling the calcination temperature. As-prepared PtCo@NC-900 shows the optimal HER performance in 0.5 M H2SO4, resulting in a high mass activity of 4.31 A mgPt-1 and excellent operation durability, which far exceeds that of commercial 20 wt % Pt/C (0.30 A mgPt-1). Density functional theory calculations further reveal that the improved HER activity on PtCo(111) is originated from the strong electronic interaction between Pt and Co with favorable electron transfer, allowing for a more suitable binding strength for hydrogen (i.e., ΔG*H = -0.164 eV) compared with that of pristine Pt(111) (-0.287 eV).

Photoluminescence Lightening: Extraordinary Oxygen Modulated Dynamics in WS2 Monolayers.

Transition metal dichalcogenide monolayers exhibit ultrahigh surface sensitivity since they expose all atoms to the surface and thereby influence their optoelectronic properties. Here, we report an intriguing lightening of the photoluminescence (PL) from the edge to the interior over time in the WS2 monolayers grown by physical vapor deposition method, with the whole monolayer brightened eventually. Comprehensive optical studies reveal that the PL enhancement arises from the p doping induced by oxygen adsorption. First-principles calculations unveil that the dissociation of chemisorbed oxygen molecule plays a significant role; i.e., the dissociation at one site can largely promote the dissociation at a nearby site, facilitating the photoluminescence lightening. In addition, we further manipulate such PL brightening rate by controlling the oxygen concentration and the temperature. The presented results uncover the extraordinary surface chemistry and related mechanism in WS2 monolayers, which deepens our insight into their unique PL evolution behavior.

Extranodal extension is an independent predictor of extensive nodal metastasis in T1 papillary thyroid cancer.

PURPOSE: Extensive lymph node metastasis (ELM) can occur in some patients with T1 papillary thyroid cancer (PTC). However, the risk factors for ELM in patients with T1 PTC have not been fully explored. In this study, we aimed to examine the association between extranodal extension (ENE) and ELM in patients with T1 PTC. PATIENTS AND METHODS: We identified 645 consecutive patients who had T1 PTC initially resected at our centre. Clinical and pathological data were reviewed. Univariate and multivariate logistic regression analyses were performed to identify the risk factors for ELM. RESULTS: ELM was identified in 3.9% of T1 PTC patients, and ENE was identified in 8.1% of patients. ENE was associated with male sex, large tumour size, more positive nodes, and comprehensive surgical treatment. In multivariate analysis, three variables were independently associated with ELM, including ENE (odds ratio [OR], 11.15; 95% confidence interval [CI], 4.54 to 27.30; P < 0.001), age (OR, 0.96; 95% CI, 0.93 to 0.99; P = 0.022), and tumour size (OR, 1.18; 95% CI, 1.06 to 1.31; P = 0.002). Bilateral multifocality and sex were not independently associated with ELM. CONCLUSION: ENE is a strong independent predictor of ELM in patients with T1 PTC. Patients with ENE-positive nodes might need extensive neck dissection.