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Transition-metal phosphides (TMPs) have attracted extensive attention in energy-related fields, especially for electrocatalytic hydrogen evolution reaction (HER). However, it is imperative to develop a facile and time-consuming approach to prepare metal phosphides with satisfactory catalytic performance. Herein, nitrogen-doped CoP-Co2P decorated with Ru (Ru/N-CoP-Co2P) is synthesized (Ru/N-CoP-Co2P) through a hydrothermal route and following an ultrafast and simple microwave avenue within 20 s. The achieved Ru/N-CoP-Co2P possesses an interconnected porous morphology to expose abundant active sites and accelerate the mass transport. Moreover, N doping and Ru-supported decorated Ru/N-CoP-Co2P also play a key role in promoting the electrocatalytic activity. Therefore, the as-designed Ru/N-CoP-Co2P presents good catalytic performance for the HER in a wide pH range. Ru/N-CoP-Co2P merely needs overpotentials of 63, 100, and 65 mV to obtain 10 mA cm-2 in acidic, alkaline, and seawater electrolytes. This research provides a novel and efficient strategy for the synthesis of TMPs with highly efficient catalytic activity.
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The developed strategies for synthesizing metal phosphides are usually cumbersome and pollute the environment. In this work, an ultrafast (30 s) quasi-solid-state microwave approach is developed to construct cobalt-molybdenum phosphide decorated with Ru (Ru/CoxP-MoP) featured porous morphology with interconnected channels. The specific nanostructure favors mass transport, such as electrolyte bubbles transfer and exposing rich active sites. Moreover, the coupling effects between metallic elements, especially the decorated Ru, also act as a pivotal role on enhancing the electrocatalytic performance. Benefiting from the effects of composition and specific nanostructure, the prepared Ru/CoxP-MoP exhibits efficient HER performance with a current density of 10 mA cm-2 achieved in 1 m KOH, 0.5 m H2SO4, seawater containing 1 m KOH and 1 m PBS, with overpotentials of 52, 59, 55, 90 mV, and coupling with good stability. This work opens a novel and fast avenue to design metal-phosphide-based nanomaterials in energy-conversion and storage fields.
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The current treatment for osteosarcoma (OS) is based on surgery combined with systemic chemotherapy, however, gene therapy has been hypothesized to improve patient survival rates. The density-enhanced protein domain 1 protein (DEPDC1) functions as a crucial determinant in the advancement of OS, which is highly expressed in OS cells. The current study was designed to delve into the effect and mechanism of DEPDC1 and phosphotyrosine-picked threonine tyrosine kinase (TTK) in OS. The expression of DEPDC1 and TTK in OS cells was detected by western blotting. Furthermore, the assessment of glycolysis encompassed the quantification of extracellular acidification rate, glucose uptake rate, lactate concentration, and the expression of glucose transporter 1, hexokinase 2, and pyruvate kinase M2. Finally, the functions of DEPDC1 and TTK in autophagy and ras-extracellular signal-regulated kinase signaling were determined by western blotting after interfering with DEPDC1 in SaOS-2 cells. The results revealed that DEPDC1 and TTK were upregulated in OS cell lines and interfering with DEPDC1 inhibited glycolysis and autophagy in OS cells. Furthermore, the STRING database suggested that DEPDC1 and TTK perform targeted binding. Notably, the results of the present study revealed that DEPDC1 upregulated RAS expression through TTK and enhanced ERK activity, thereby affecting glycolysis and autophagy in OS cells. Collectively, the present investigation demonstrated that DEPDC1 affected autophagy-dependent glycolysis levels of OS cells by regulating RAS/ERK signaling through TTK.
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Compared with the healthy patients, patients with osteoporosis had a lower Hounsfield unit (HU) value and a higher vertebral bone quality (VBQ) score. Both the HU value and VBQ score can simply distinguish patients with osteoporosis (OP), with a cutoff value of HU value < 97.06 and VBQ score > 3.08. INTRODUCTION: The purpose of this study is to determine whether the opportunistic use of computed tomography (CT) or magnetic resonance imaging (MRI) is effective for identifying spine surgical patients with OP. METHODS: We retrospectively evaluated 109 lumbar spine surgery patients who received lumbar quantitative CT (QCT) and MRI. Using the area under the curve, the CT-based HU value and MRI-based VBQ score were calculated. Then, based on the QCT results, receiver operating characteristic (ROC) curves were constructed to determine the diagnostic performance of the HU value and VBQ score. RESULTS: The HU value was significantly lower in the OP group, and the VBQ score was significantly higher in the OP group. Using the area under the curve, the diagnostic performance of the HU value and VBQ score for OP were 0.959 and 0.880, respectively. The diagnostic threshold values determined with optimal sensitivity and specificity were an HU value of 97.06 and a VBQ score of 3.08. CONCLUSION: Opportunistic use of CT and MRI can simply distinguish patients with OP, which are expected to be potential alternatives to T-score for the osteoporosis screening.
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Developing electrocatalysts with high activity and durability for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in both acidic and alkaline electrolytes remains challenging. In this study, we synthesize a self-supported ruthenium-iron oxide on carbon cloth (Ru-Fe-Ox/CC) using solvothermal methods followed by air calcination. The morphology of the nanoparticle exposes numerous active sites vital for electrocatalysis. Additionally, the strong electronic interaction between Ru and Fe enhances electrocatalytic kinetics optimization. The porous structure of the carbon cloth matrix facilitates mass transport, improving electrolyte penetration and bubble release. Consequently, Ru-Fe-Ox/CC demonstrates excellent catalytic performance, achieving low overpotentials of 32 mV and 28 mV for HER and 216 mV and 228 mV for OER in acidic and alkaline electrolytes, respectively. Notably, only 1.48 V and 1.46 V are required to reach 10 mA cm-2 for efficient water-splitting in both mediums, exhibiting remarkable stability. This research offers insights into designing versatile, highly efficient catalysts suitable for varied pH conditions.
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Improving the efficiency of overall water splitting (OWS) is crucial due to the slow four-electron transfer process in the oxygen evolution reaction (OER). The coupling of the thermodynamically favorable hydrazine oxidation reaction (HzOR) with the hydrogen evolution reaction (HER) significantly boosts hydrogen production. A Ru-decorated MoNi/MoO2 micropillar (Ru-MoNi/MoO2) has been synthesized using a hydrothermal followed by reduction annealing. Benefiting from Ru moderating the active interface of Mo-based alloys/oxides and the unique one-dimensional micropillar morphology. The synthesized Ru-MoNi/MoO2 exhibits outstanding bifunctional activity for HER and HzOR, achieving 10 mA cm-2 at merely -13 mV and -34 mV in 1 M KOH and 1 M KOH + 0.5 M N2H4, respectively. Notably, with Ru-MoNi/MoO2 in a dual-electrode setup, only 0.57 V is needed to achieve 50 mA cm-2, demonstrating good stability and facilitating hydrazine-assisted water splitting (OHzS). This work offers insights into the modulation of alloy/metal oxide active interfaces, contributing to the development of efficient bifunctional catalysts for HER and HzOR.
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The Pt-based alloys can moderate the binding energies of oxygenated species on the catalytic surface, endowing the superior catalytic performance towards oxygen reduction reaction (ORR). Nevertheless, it is still challenging to explore general methods to synthesize structurally ordered intermetallics with uniform distributions. Herein, the strong metal-support interaction is employed to facilitate the interdiffusion of Pt/M atoms by establishing a tunnel of oxygen vacancy on ultrathin Ti3C2Tx (MXene) sheets, synthesizing the ordered PtFe, PtCo, PtZn, PdFe, PdZn intermetallics loaded onto Ti3C2Tx. Furthermore, the in-situ generation of Ti-O from Ti3C2Tx could be bonded with Pt and forming Pt-O-Ti, resulting in charge redistribution through Pt-O-Ti structure. Theoretical calculations demonstrate that the valuable charge redistribution can be observed at the interface and extended even to at the distance of two nanometers from the interface, which can modulate the Pt-Pt distance, optimize Pt-O binding energy and enhance intrinsic activity towards ORR. The strong coupling interaction between PtFe and Ti3C2Tx containing the titanium oxide layer endows the high stability of the composites. This work not only presents a general synthesis strategy for intermetallics but also provides a new insight that metal-support interaction is essential for the structural evolution of intermetallics on materials with oxygen vacancies.
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Modern detectors commonly employ classification scores to reflect the localization quality of detection results. However, there exists an inconsistency between them, misguiding the selection of high-quality predictions and providing unreliable results for downstream applications. In this paper, we find that the root of this confidence inconsistency lies in the inaccurate IoU estimation and the spatial misalignment of the learned features between the classification and localization tasks. Therefore, a Confidence-Consistent Detector (CCDet) which includes the Distribution-based IoU Prediction (DIP) and Consistency-aware label assignment (CLA), is proposed. DIP provides more stable and accurate IoU estimation by learning the probability distribution over the IoU range and employing the expectation as the predicted IoU. CLA adopts both the prediction performance and consistency degree of samples as assignment metrics to select positives, which guides the classification and localization tasks to promote similar feature distribution. Comprehensive experiments demonstrate that CCDet can effectively mitigate the confidence inconsistency between classification and localization, and achieve stable improvement across different baselines. On the test-dev set of MS COCO, CCDet acquires a single-model single-scale AP of 50.1%, surpassing most of the existing object detectors.
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The improvement of the hydrogen evolution reaction (HER) performance of nanomaterials is associated with the interfacial synergistic interaction and their hydrogen adsorption kinetics. Nevertheless, it is still a challenge to accelerate the proton transfer and optimize the HER kinetics by constructing Pt-supported heterostructures based on the hydrogen spillover phenomenon. Herein, oxygen vacancies on the surface of MXene nanosheets were constructed via a high-temperature annealing method, which was employed to anchor/stabilize Pt nanoparticles and fabricate a Pt/MXene heterostructure. EPR and XPS analyses verified the presence of oxygen vacancies, which could enhance the intrinsic HER activity of the MXene. The HER catalytic performance was investigated by taking into account the surface structure of the MXene affected by the annealing temperature, the concentration of Pt and the number of deposition cycles. Electrochemical results showed that Pt/MXene with higher utilization of Pt was obtained at 900 °C and 0.05 mgPt mL-1. The 0.05-Pt/MXene-900 obtained at deposition of 60 cycles in 0.5 M H2SO4 solution exhibited the optimized HER activity. The overpotential was 22 mV at a current density of 10 mA cm-2 and the Tafel slope was 42.41 mV dec-1. Furthermore, the accelerated HER kinetics was mainly due to the electron trapping ability of the MXene, small particles of Pt, as well as the enhanced charge transfer between the oxygen vacancies of the MXene and Pt. This strategy for constructing Pt-supported heterostructures based on the vacancy anchoring effects provides new ideas for the design of well-defined electrocatalysts toward the HER.
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OBJECTIVES: We aimed to prospectively investigate the benefit of using augmented reality (AR) for surgery residents learning aneurysm surgery. MATERIALS AND METHODS: Eight residents were included, and divided into an AR group and a control group (4 in each group). Both groups were asked to locate an aneurysm with a blue circle on the same screenshot after their viewing of surgery videos from both AR and non-AR tests. Only the AR group was allowed to inspect and manipulate an AR holographic representation of the aneurysm in AR tests. The actual location of the aneurysm was defined by a yellow circle by an attending physician after each test. Localization deviation was determined by the distance between the blue and yellow circle. RESULTS: Localization deviation was lower in the AR group than in the control group in the last 2 tests (AR Test 2: 2.7 ± 1.0 mm vs. 5.8 ± 4.1 mm, p = 0.01, non-AR Test 2: 2.1 ± 0.8 mm vs. 5.9 ± 5.8 mm, p < 0.001). The mean deviation was lower in non-AR Test 2 as compared to non-AR Test 1 in both groups (AR: p < 0.001, control: p = 0.391). The localization deviation of the AR group decreased from 8.1 ± 3.8 mm in Test 2 to 2.7 ± 1.0 mm in AR Test 2 (p < 0.001). CONCLUSION: AR technology provides an effective and interactive way for neurosurgery training, and shortens the learning curve for residents in aneurysm surgery.
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Aneurisma , Realidade Aumentada , Cirurgia Assistida por Computador , Humanos , Curva de Aprendizado , Cirurgia Assistida por Computador/métodos , Procedimentos Neurocirúrgicos/métodosRESUMO
BACKGROUND: Experience using flow diverter devices (FDDs) to treat proximal (M1) middle cerebral artery aneurysms associated with the lenticulostriate artery (M1A-LA) remains limited. This study aimed to examine the efficacy and safety of an FDD to manage M1A-LA. METHOD: Patients with M1A-LA who received FDD treatment at a single center were included in the analysis. Data on the baseline characteristics, postoperative conditions, and follow-up results of the participants were recorded and analyzed. The aneurysms were categorized into three subtypes based on morphology and location. Aneurysms confined to the M1 segment were categorized as subtype A. Those extending to the M2 segment were classified as subtype B. Aneurysms designated as subtype C were confined to the M1 segment but with another independent aneurysm in the distal artery and the presence of healthy vessels between the two. Subgroup analyses were conducted on these subtypes and aneurysm sizes. To assess the consistency of follow-up results, Cronbach's kappa/alpha was used to calculate inter-rater variability. Somers's D coefficient was used to assess the correlation between each subgroup and the imaging outcomes; Fisher's exact test was used to compare the variability among the subgroups. RESULT: The cohort comprised 11 patients. Their Modified Rankin Scale scores between the perioperative and follow-up periods did not differ. During the follow-up period, four patients had completely occluded aneurysms, and five patients had partial occlusions. The remaining patients did not present with changes in their aneurysms. The kappa coefficient was 0.864 (p < 0.001). M1A-LA was divided into subtypes A, B, and C. Subtype A (defined as an aneurysm completely located in the M1 segment) had a higher complete occlusion rate than that of subtypes B and C, Somers's D R/C correlation coefficient was 0.553, with a 95% confidence interval of 0.1229-0.9823 (p = 0.009). The radiographic follow-up findings were not significantly correlated with the size of the aneurysm (p = 0.121) or the use of coiling (p = 0.903). No significant differences in subtypes (p = 0.264), aneurysm size (p = 0.657), or coiling use (p > 0.999) were observed. CONCLUSION: FDDs were safe and possibly effective against M1A-LA. However, they were not as effective as for intracranial aneurysms in other locations. FDDs are a satisfactory treatment option for M1A-LA, particularly for subtype A aneurysms.
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Embolização Terapêutica , Procedimentos Endovasculares , Aneurisma Intracraniano , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Aneurisma Intracraniano/etiologia , Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/cirurgia , Resultado do Tratamento , Procedimentos Endovasculares/métodos , Embolização Terapêutica/métodosRESUMO
Evidence-based medicine shows that obesity is associated with a wide range of cardiovascular (CV) diseases. Obesity can lead to changes in cardiac structure and function, which can lead to obese cardiomyopathy, subclinical cardiac dysfunction, and even heart failure. It also increases the risk of atrial fibrillation and sudden cardiac death. Many invasive and noninvasive diagnostic methods can detect obesity-related heart disease at an early stage, so that appropriate measures can be selected to prevent adverse CV events. However, studies have shown a protective effect of obesity on clinical outcomes of CV disease, a phenomenon that has been termed the obesity paradox. The "obesity paradox" essentially refers to the fact that the classification of obesity defined by body mass index (BMI) does not consider the impact of obesity heterogeneity on CV disease prognosis, but simply puts subjects with different clinical and biochemical characteristics into the same category. In any case, indicators such as waist-to-hip ratio, ectopic body fat qualitative and quantitative, and CV fitness have been shown to be able to distinguish different CV risks in patients with the same BMI, which is convenient for early intervention in an appropriate way. A multidisciplinary approach, including lifestyle modification, evidence-based generic and novel pharmacotherapy, and surgical intervention, can improve CV outcomes in overweight/obese patients.
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Doenças Cardiovasculares , Insuficiência Cardíaca , Humanos , Obesidade/complicações , Obesidade/diagnóstico , Obesidade/terapia , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/diagnóstico , Prognóstico , Sobrepeso/complicações , Índice de Massa Corporal , Fatores de RiscoRESUMO
Anionic modification engineering is a crucial approach to develop highly efficient electrocatalysts for hydrogen evolution reaction. Herein, halogen elements (X = Cl, Br, and I)-modified Ru-based nanosheets (X-Ru/RuP2) are designed by rapid and eco-friendly microwave-phosphide plasma approach within 60 s. Experimental and density functional theory calculations verify that the introduced halogen element, especially Br, can optimize the surface intermediates adsorption. Specially, the designed Br-Ru/RuP2 favors the water dissociation and following hydrogen adsorption/desorption process. Then, the as-synthesized Br-Ru/RuP2 exhibits low overpotential of 34 mV to reach 10 mA cm-2 coupled with small Tafel slope of 27 mV dec-1 in alkaline electrolyte with excellent long-term stability. Moreover, the electrocatalytic performances in acid and neutral media are also boosted via Br element modification. This work paves a novel way to regulate the electronic structure of Ru-based compounds, and then can boost the electrocatalytic kinetics.
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Transition metal phosphides are ideal inexpensive electrocatalysts for water-splitting, but the catalytic activity still falls behind that of noble metal catalysts. Therefore, developing valid strategies to boost the electrocatalytic activity is urgent to promote large-scale applications. Herein, a microwave combustion strategy (20 s) is applied to synthesize N-doped CoP/Ni2P heterojunctions (N-CoP/Ni2P) with porous structure. The porous structure expands the specific surface area and accelerates the mass transport efficiency. Importantly, the pyrrolic N/pyridinic N content is adjusted by changing the amount of urea during the synthesis process and then optimizing the adsorption/desorption capacity for H*/OH* to enhance the catalyst activity. Then, the synthesized N-CoP/Ni2P exhibits small overpotentials of 111 and 133 mV for HER in acidic and alkaline electrolytes and 290 mV for OER in alkaline electrolytes. This work provides an original and efficient approach to the synthesis of porous metal phosphides.
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Developing bifunctional catalysts for overall water splitting with high activity and durability at high current density remains a challenge. In an attempt to overcome this bottleneck, in this work, unique CoNiFe-layered double hydroxide nanoflowers are in situ grown on nickel-iron (NiFe) foam through a corrosive approach and following a chemical vapor deposition process to generate nitrogen-doped carbon nanotubes at the presence of melamine (CoNiFe@NCNTs). The coupling effects between various metal species act a key role in accelerating the reaction kinetics. Moreover, the in situ formed NCNTs also favor promoting electrocatalytic activity and stability. For oxygen evolution reaction it requires low overpotentials of 330 and 341 mV in 1M KOH and 1M KOH + seawater to drive 500 mA cm-2. Moreover, water electrolysis can be operated with CoNiFe@NCNTs as both anode and cathode with small voltages of 1.95 and 1.93 V to achieve 500 mA cm-2 in 1M KOH and 1M KOH + seawater, respectively.
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Rational design and controllable synthesis of Pt-based materials with intimate interfacial contact open up the possibility for boosting the performance of the ORR (oxygen reduction reaction) and HER (hydrogen evolution reaction). However, it is still challenging to prevent the oxidation of Pt during the formation of alloys and to clarify the interfacial synergistic effects on the catalytic performance between Pt alloys and the dispersed substrate. Herein, the wet chemical stripping and intercalation methods were employed to synthesize a two-dimensional (2D) MXene with abundant defect sites, which can anchor Pt3Co/Pt3Ni nanoparticles and prevent the oxidation of Pt during the process of atomic rearrangement at high temperatures. The obtained Pt3Co/MXene and Pt3Ni/MXene displayed different phase compositions and alloying degrees on adjusting the annealing temperature. Electrochemical test results showed that the optimized HER and ORR electrocatalytic activities occurred at 700 °C. Compared with Pt3Ni/MXene-700, Pt3Co/MXene-700 exhibited an HER overpotential of 1.3 mV at a current density of 10 mA cm-2, and a Tafel slope of 27.11 mV dec-1 in 0.1 M HClO4 solution. Furthermore, Pt3Co/MXene-700 exhibited an ORR half-wave potential of 0.897 V, and a mass activity of 241.1 mA mg-1Pt in 0.1 M HClO4 solution. This can be attributed to the formation of intermetallic compounds in Pt3Co/MXene. The electronic structure analysis showed that the enhanced performance could be assigned to the electron-capturing capability of the MXene, less oxidation of Pt and synergistic interactions between the Pt alloy and the MXene substrate. These findings provide a new strategy for the synthesis of highly active HER/ORR catalysts and broaden the way for the design of MXene-based catalysts.
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Developing efficient electrocatalysts for hydrogen evolution reaction (HER) in full pH range can promote the practical applications of hydrogen energy. In this work, nitrogen doped carbon nanosheets supported RuM (Mo, W, Cr) (RuM/NCN) are prepared through an ultrafast microwave approach. The carbon nanosheet structure coupled with the ultrasmall RuM nanoparticles can expose rich active sites to optimize the catalytic activity. Moreover, the strong metal-support interactions also favor to accelerate the reactions kinetics and improve stability. Thus, the developed RuMo/NCN (RuW/NCN) show excellent HER catalytic activities with overpotentials of 72 (75) mV, 82 (82) mV and 124 (119) mV to reach current density of 10 mA cm -2 in 1 M KOH, 0.5 M H2SO4 and alkaline seawater, respectively, and also achieve excellent performance in 1 M PBS. This work provides a valid and novel avenue to design efficient electrocatalysts in renewable energy-related fields.
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Molybdenum phosphide (MoP) has received increasing attention for the hydrogen evolution reaction (HER) due to its Pt-like electronic structure and high electrical conductivity. In this work, a flake-like Ru-doped MoP with phosphorus vacancy (Ru-MoP-PV) electrocatalyst is synthesized for the first time by a simple and rapid room-temperature microwave approach within 30 s. The created abundant phosphorus vacancies provide rich active sites and favor rapid electron transfer. The introduced Ru also enhances the catalytic activity of the synthesized electrocatalyst efficiently. Then, the designed Ru-MoP-PV possesses low overpotentials for HER with 79, 100, and 161 mV in 1.0 M KOH, 0.5 M H2SO4, and 1.0 M phosphate-buffered saline to obtain 10 mA cm-2. The Ru-MoP-PV and NiFe-layered double hydroxide are used as the cathode and the anode, respectively, to drive water splitting and just need a low cell voltage of 1.6 V to achieve 10 mA cm-2. This work provides a feasible way for the rapid production of metal phosphides for energy conversion and storage applications.