ABSTRACT
The electrochemical NH3 synthesis on TiNO is proposed to follow the Mars-van Krevelen (MvK) mechanism, offering more favorable N2 adsorption and activation on the N vacancy (Nv) site, compared to the conventional associative mechanism. The regeneration cycle of Nv represents the rate-determining step in this process. This study investigates a series of TM (Fe, Co, Ni, Ru, Rh, Pd, Os, Ir, and Pt)-TiNO to explore the *H migration (from TM to TiNO)-promoted Nv cycle. The screening results indicate that Ni-TiNO exhibits strong H2O decomposition for *H production with 0.242 eV and low *H migration resistance with 0.913 eV. Notably, *H migration from Ni to TiNO significantly reduces the Nv formation energy to 0.811 eV, compared to 1.387 eV on pure TiNO. Meanwhile, in the presence of *H, Nv formation takes precedence over Tiv and Ov. Lastly, electronic performance calculations reveal that the collaborative function provided by Ni and Nv enables highly stable and efficient NH3 synthesis. The *H migration-assisted MvK mechanism demonstrates effective catalytic cycle performance in electrochemical N2 fixation and may have potential applicability to other hydrogenation reactions utilizing water as a proton source.
ABSTRACT
The floatable photocatalyst at N2-water interface allows the adequate supply of N2 reactant and the utilization of photothermal energy for photocatalytic N2 fixation, however, the presence of non-volatile NO3- product poses a challenge to the stability as it easily covers the catalytic active sites. Herein, a floatable TiO2/Bi/CC (Carbon cloth) photocatalyst was designed, in which the non-volatile NO3- can be transformed to the volatile NH3 via the newly synergistic relay photocatalysis pathway (N2 â NO3- â NH3) between TiO2 (N2 â NO3-) and Bi (NO3- â NH3). Attractively, the spontaneous NO3- â NO2- step occurs on Bi component to promote the relay pathway performing. Therefore, TiO2/Bi/CC system displays better long-term stability than TiO2/CC, and moreover, it achieves a higher NH3 yield of 8.28 mmol L-1 h-1 g-1 (i.e. 4.14 mmol h-1 m-2) than that 1.46 mmol L-1 h-1 g-1 for TiO2/Bi powder. Importantly, the N2 fixation products by TiO2/Bi/CC effectively promote lettuce growth and enhance lettuce nutrient contents, which further validates the feasibility of this system in large-scale application of crop cultivation.
ABSTRACT
Bismuth vanadate (BVO) is regarded as an exceptional photoanode material for photoelectrochemical (PEC) water splitting, but it is restricted by the severe photocorrosion and slow water oxidation kinetics. Herein, a synergistic strategy combined with a Co3(HPO4)2(OH)2 (CoPH) cocatalyst and an Al2O3 (ALO) passivation layer was proposed for enhanced PEC performance. The CoPH/ALO/BVO photoanode exhibits an impressive photocurrent density of 4.9 mA cm-2 at 1.23 VRHE and an applied bias photon-to-current efficiency (ABPE) of 1.47% at 0.76 VRHE. This outstanding PEC performance can be ascribed to the suppressed surface charge recombination, facilitated interfacial charge transfer, and accelerated water oxidation kinetics with the introduction of the CoPH cocatalyst and ALO passivation layer. This work provides a novel and synergistic approach to design an efficient and stable photoanode for PEC applications by combining an oxygen evolution cocatalyst and a passivation layer.
ABSTRACT
The Volmer step in alkaline hydrogen evolution reactions (HERs), which supplies H* to the following steps by cleaving H-O-H bonds, is considered the rate-determining step of the overall reaction. The Volmer step involves water dissociation and adsorbed hydroxyl (*OH) desorption; Ru-based catalysts display a compelling water dissociation process in an alkaline HER. Unfortunately, the strong affinity of Ru for *OH blocks the active sites, resulting in unsatisfactory performance during HER processes. Hence, this study investigates a series of key descriptors (ΔG*H2O, ΔG*H-OH, ΔG*H, and ΔG*OH) of TM (Fe, Co, Ni, Ru, Rh, Pd, Os, Ir, or Pt)-Ru/Mo2Ti2C3O2 to systematically explore the effects of bimetallic site interactions on the kinetics of the Volmer step. The results indicate that bimetallic catalysts effectively reduced the strong adsorption of *OH on Ru sites; especially, the NiRu diatomic state shows the highest electron-donating ability, which promoted the smooth migration of *OH from Ru sites to Ni sites. Therefore, Ru, Ni and MXenes are suitable to serve as water adsorption and dissociation sites, *OH desorption sites, and H2 release sites, respectively. Ultimately, NiRu/Mo2Ti2C3O2 promotes Volmer kinetics and has the potential to improve alkaline HERs. This work provides theoretical support for the construction of synergistic MXene-based diatomic catalysts and their wide application in the field of alkaline HERs.
ABSTRACT
What we believe to be a novel integrated circular polarization dynamic converter (CPDC) is proposed based on the four-layer mirror symmetry structure. By designing the twisted structure and rearranging the orientation direction of liquid crystal molecules for each layer, the application wavelength range could be broadened. For the viewing angle expansion, negative birefringent films are selected to compensate for the retardation deviation under oblique incidence. Finally, the particle swarm algorithm is used to optimize the whole configuration, and the polarization conversion efficiency calculated by the finite element method (FEM) can achieve 90% in the wavelength range from 320â nm to 800â nm at an ultrawide view of 160°. Compared with traditionally active liquid crystal waveplates, the design has potential advantages in both wavelength and field of view (FOV) and provides the possibility for the integrated and flimsy fabrication of devices.
ABSTRACT
PURPOSE: To compare the long-term clinical and oncologic outcomes of laparoscopic partial nephrectomy (LPN) and laparoscopic radical nephrectomy (LRN) in patients with renal cell carcinoma (RCC) > 4 cm. METHODS: We retrospectively reviewed the records of all patients who underwent LPN or LRN in our department from January 2012 to December 2017. Of the 151 patients who met the study selection criteria, 54 received LPN, and 97 received LRN. After propensity-score matching, 51 matched pairs were further analyzed. Data on patients' surgical data, complications, histologic data, renal function, and survival outcomes were collected and analyzed. RESULTS: Compared with the LRN group, the LPN group had a longer operative time (135 min vs. 102.5 min, p = 0.001), larger intraoperative bleeding (150 ml vs. 50 ml, p < 0.001), and required longer stays in hospital (8 days vs. 6 days, p < 0.001); however, the level of ECT-GFR was superior at 3, 6, and 12 months (all p < 0.001). Similarly, a greater number of LRN patients developed CKD compared with LPN until postoperative 12 months (58.8% vs. 19.6%, p < 0.001). In patients with preoperative CKD, LPN may delay the progression of the CKD stage and even improve it when compared to LRN treatment. There were no significant differences between the two groups for OS, CSS, MFS, and PFS (p = 0.06, p = 0.30, p = 0.90, p = 0.31, respectively). The surgical method may not be a risk factor for long-term survival prognosis. CONCLUSION: LPN preserves renal function better than LRN and has the potential value of significantly reducing the risk of postoperative CKD, but the long-term survival prognosis of patients is comparable.
Subject(s)
Carcinoma, Renal Cell , Kidney Neoplasms , Laparoscopy , Renal Insufficiency, Chronic , Humans , Carcinoma, Renal Cell/pathology , Kidney Neoplasms/pathology , Retrospective Studies , Treatment Outcome , Laparoscopy/methods , Nephrectomy/methods , Renal Insufficiency, Chronic/surgeryABSTRACT
Three-dimensional porous carbon materials with moderate heteroatom-doping have been extensively investigated as promising electrode materials for energy storage. In this study, we fabricated a 3D cross-linked chitosan-dicyandiamide-VOSO4 hydrogel using a polymerization process. After pyrolysis at high temperature, 3D porous VOx/N-doped carbon nanosheet hybrids (3D VNCN) were obtained. The unique 3D porous skeleton, abundant doping elements, and presence of VOx 3D VNCN pyrolyzed at 800 °C (3D VNCN-800) ensured excellent electrochemical performance. The 3D VNCN-800 electrode exhibits a maximum specific capacitance of 408.1 F·g-1 at 1 A·g-1 current density and an admirable cycling stability with 96.8% capacitance retention after 5000 cycles. Moreover, an assembled symmetrical supercapacitor based on the 3D VNCN-800 electrode delivers a maximum energy density of 15.6 Wh·Kg-1 at a power density of 600 W·Kg-1. Our study demonstrates a potential guideline for the fabrication of porous carbon materials with 3D structure and abundant heteroatom-doping.
ABSTRACT
The development of low-cost and high-performance bifunctional electrocatalysts for overall water splitting is still challenging. Herein, we employed a facile electrodeposition method to prepare bifunctional cobalt phosphide for overall water splitting. The needle-like cobalt phosphide (Co-P-1) nanoarray is uniformly distributed on nickel foam. Co-P-1 exhibits excellent electrocatalytic activity for hydrogen evolution reaction (HER, 85 mV at 10 mA/cm2, 60 mV/dec) and oxygen evolution reaction (OER, 294 mV at 50 mA/cm2, 60 mV/dec). The cell-voltage of 1.60 V is found to achieve the current density of 10 mA/cm2 for overall water splitting in the two-electrode system, comparable to that of previously reported Pt/C/NF||RuO2/NF. The excellent electrocatalytic performance can be attributed to the needle-like structure with more active sites, accelerated charge transfer and evolved bubbles' release. This work can provide new approach to the development of a bifunctional electrocatalyst for overall water splitting.
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Rapid advances in light microscopy and development of all-optical electrophysiological imaging tools have greatly leveraged the speed and the depth of neurobiology studies. Calcium imaging is a common method that is useful for measuring calcium signals in cells and has been used as a functional proxy for neuronal activity. Here I describe a simple, stimulation-free approach that measures neuronal network activity and single-neuron dynamics in human neurons. This protocol provides the experimental workflow that includes step-wise illustrations of sample preparations, data processing, and analyses that can be used for quick phenotypical assessment and serves as a quick functional readout for mutagenesis or screen effort for neurodegenerative studies.
Subject(s)
Calcium , Neurons , Humans , Neurons/physiology , Optical Imaging/methods , Electrophysiological PhenomenaABSTRACT
The epidemic of coronavirus disease 2019 (COVID-19) was a huge disaster to human society. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which led to COVID-19, has resulted in a large number of deaths. Even though the reverse transcription-polymerase chain reaction (RT-PCR) is the most efficient method for the detection of SARS-CoV-2, the disadvantages (such as long detection time, professional operators, expensive instruments, and laboratory equipment) limit its application. In this review, the different kinds of nano-biosensors based on surface-enhanced Raman scattering (SERS), surface plasmon resonance (SPR), field-effect transistor (FET), fluorescence methods, and electrochemical methods are summarized, starting with a concise description of their sensing mechanism. The different bioprobes (such as ACE2, S protein-antibody, IgG antibody, IgM antibody, and SARS-CoV-2 DNA probes) with different bio-principles are introduced. The key structural components of the biosensors are briefly introduced to give readers an understanding of the principles behind the testing methods. In particular, SARS-CoV-2-related RNA mutation detection and its challenges are also briefly described. We hope that this review will encourage readers with different research backgrounds to design SARS-CoV-2 nano-biosensors with high selectivity and sensitivity.
ABSTRACT
The electrochemical hydrogen evolution reaction (HER) in alkaline media provides an environmentally friendly industrial application approach to replace traditional fossil energy. The search for efficient, low-cost, and durable active electrocatalysts is central to the development of this area. Transition metal carbides (MXenes) have been emerging as a new family of two-dimensional (2D) materials that have great potential in the HER. Herein, density functional theory calculations are performed to systematically explore the structural and electronic properties and alkaline HER performances of Mo-based MXenes, as well as the influence of species and the coordination environment of single atoms on the improvement of the electrocatalytic activity of Mo2Ti2C3O2. The results show that Mo-based MXenes (Mo2CO2, Mo2TiC2O2, and Mo2Ti2C3O2) exhibit excellent H binding ability, while slow water decomposition kinetics hinders their HER performance. Replacing the O-terminal of Mo2Ti2C3O2 with a Ru single-atom (RuS-Mo2Ti2C3O2) could promote the decomposition of water owing to the stronger electron-donating ability of the atomic state Ru. In addition, Ru could also improve the binding ability of the catalyst to H by adjusting the surface electron distribution. As a result, RuS-Mo2Ti2C3O2 exhibits excellent HER performance with a water decomposition potential barrier of 0.292 eV and a H adsorption Gibbs free energy of -0.041 eV. These explorations bring new prospects for single atoms supported on Mo-based MXenes in the alkaline hydrogen evolution reaction.
ABSTRACT
A facile hydrothermal process has been developed to synthesize the α-Fe2O3 nanowire arrays with a preferential growth orientation along the [110] direction. The W/α-Fe2O3/FTO memory device with the nonvolatile resistive switching behavior has been achieved. The resistance ratio (RHRS/RLRS) of the W/α-Fe2O3/FTO memory device exceeds two orders of magnitude, which can be preserved for more than 103s without obvious decline. Furthermore, the carrier transport properties of the W/α-Fe2O3/FTO memory device are dominated by the Ohmic conduction mechanism in the low resistance state and trap-controlled space-charge-limited current conduction mechanism in the high resistance state, respectively. The partial formation and rupture of conducting nanofilaments modified by the intrinsic oxygen vacancies have been suggested to be responsible for the nonvolatile resistive switching behavior of the W/α-Fe2O3/FTO memory device. This work suggests that the as-prepared α-Fe2O3 nanowire-based W/α-Fe2O3/FTO memory device may be a potential candidate for applications in the next-generation nonvolatile memory devices.
ABSTRACT
In this paper, the effect of nitrogen annealing on the resistive switching characteristics of the rutile TiO2 nanowire-based W/TiO2/FTO memory device is analyzed. The W/TiO2/FTO memory device exhibits a nonvolatile bipolar resistive switching behavior with a high resistance ratio (RHRS/RLRS) of about two orders of magnitude. The conduction behaviors of the W/TiO2/FTO memory device are attributed to the Ohmic conduction mechanism and the Schottky emission in the low resistance state and the high resistance state, respectively. Furthermore, the RHRS/RLRS of the W/TiO2/FTO memory device is obviously increased from about two orders of magnitude to three orders of magnitude after the rapid nitrogen annealing treatment. In addition, the change in the W/TiO2 Schottky barrier depletion layer thickness and barrier height modified by the oxygen vacancies at the W/TiO2 interface is suggested to be responsible for the resistive switching characteristics of the W/TiO2/FTO memory device. This work demonstrates the potential applications of the rutile TiO2 nanowire-based W/TiO2/FTO memory device for high-density data storage in nonvolatile memory devices.
ABSTRACT
The photoelectrochemical (PEC) water splitting performance of BiVO4 (BVO), a promising photoanode material, is constrained by its extremely short hole diffusion length and slow water oxidation kinetics. Modification of oxygen evolution cocatalysts (OECs) by appropriate methods is a practical solution to enhance the PEC water splitting performance of BVO. In this work, two different nickel phosphides Ni2P and Ni12P5 were prepared by a facile and mild one-step solvothermal method, and used as OECs to modify a BVO photoanode for enhancing the PEC water splitting performance. The BVO/Ni2P and BVO/Ni12P5 photoanodes showed impressive photocurrent densities of 3.3 mA cm-2 and 3.1 mA cm-2, respectively. In addition, the PEC water splitting stability of the BVO/Ni2P photoanode was greatly enhanced compared to that of the bare BVO photoanode. Further characterization and photoelectrochemical analysis revealed that the significant improvement of the BVO photoanode performance was attributed to the effective inhibition of surface charge recombination, facilitation of interfacial charge transfer, and acceleration of water oxidation kinetics after Ni2P and Ni12P5 modification.
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Regulating electronic structures of the active site by manipulating the local coordination is one of the advantageous means to improve photocatalytic hydrogen evolution (PHE) kinetics. Herein, the ZnIn2 S4 /Mo2 TiC2 Schottky junctions are designed to be constructed through the interfacial local coordination of In3+ with the electronegative O terminal group on Mo2 TiC2 based on the different work functions. Kelvin probe force microscopy and charge density difference reveal that an electronic unidirectional transport channel across the Schottky interface from ZnIn2 S4 to Mo2 TiC2 is established by the formed local nucleophilic/electrophilic region. The increased local electron density of Mo2 TiC2 inhibits the backflow of electrons, boosts the charge transfer and separation, and optimizes the hydrogen adsorption energy. Therefore, the ZnIn2 S4 /Mo2 TiC2 photocatalyst exhibits a superior PHE rate of 3.12 mmol g-1 h-1 under visible light, reaching 3.03 times that of the pristine ZnIn2 S4 . This work provides some insights and inspiration for preparing MXene-based Schottky catalysts to accelerate PHE kinetics.
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Traditional graphite anode material typically shows a low theoretical capacity and easy lithium decomposition. Molybdenum disulfide is one of the promising anode materials for advanced lithium-ion batteries, which possess low cost, unique two-dimensional layered structure, and high theoretical capacity. However, the low reversible capacity and the cycling-capacity retention rate induced by its poor conductivity and volume expansion during cycling blocks further application. In this paper, a collaborative control strategy of monodisperse MoS2/graphite composites was utilized and studied in detail. MoS2/graphite nanocomposites with different ratios (MoS2:graphite = 20%:80%, 40%:60%, 60%:40%, and 80%:20%) were prepared by mechanical ball-milling and low-temperature annealing. The graphite sheets were uniformly dispersed between the MoS2 sheets by the ball-milling process, which effectively reduced the agglomeration of MoS2 and simultaneously improved the electrical conductivity of the composite. It was found that the capacity of MoS2/graphite composites kept increasing along with the increasing percentage of MoS2 and possessed the highest initial discharge capacity (832.70 mAh/g) when MoS2:graphite = 80%:20%. This facile strategy is easy to implement, is low-cost, and is cosmically produced, which is suitable for the development and manufacture of advance lithium-ion batteries.
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The growing economic uncertainty makes consumers realize the importance of financial preparedness and management ability. Based on the U.S. National Financial Capability Study dataset from 2009, 2012, 2015, and 2018, this study explores the nexus between consumer financial knowledge and financial behaviors of credit card use. The results indicate that financial knowledge positively affects consumer credit card ownership and desirable financial behaviors of credit card use, and is negatively related to undesirable credit card behaviors. The results are robust to different regression methods and after removing income outliers. The heterogeneity test shows that financial knowledge cannot enhance desirable credit card behaviors because of the income limitations in the low-income group. Therefore, there are implications for policymakers, financial sectors, and consumers to improve consumers' usage of credit cards and cultivate proper consumption habits by enhancing consumer financial knowledge.
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Leveraging molecular networks to discover disease-relevant modules is a long-standing challenge. With the accumulation of interactomes, there is a pressing need for powerful computational approaches to handle the inevitable noise and context-specific nature of biological networks. Here, we introduce Graphene, a two-step self-supervised representation learning framework tailored to concisely integrate multiple molecular networks and adapted to gene functional analysis via downstream re-training. In practice, we first leverage GNN (graph neural network) pre-training techniques to obtain initial node embeddings followed by re-training Graphene using a graph attention architecture, achieving superior performance over competing methods for pathway gene recovery, disease gene reprioritization, and comorbidity prediction. Graphene successfully recapitulates tissue-specific gene expression across disease spectrum and demonstrates shared heritability of common mental disorders. Graphene can be updated with new interactomes or other omics features. Graphene holds promise to decipher gene function under network context and refine GWAS (genome-wide association study) hits and offers mechanistic insights via decoding diseases from genome to networks to phenotypes.
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Tumor-infiltrating lymphocytes (TILs) have been extensively explored as prognostic biomarkers and cellular immunotherapy methods in cancer patients. However, the prognostic significance of TILs in bladder cancer remains unresolved. We evaluated the prognostic effect of TILs in bladder cancer patients. Sixty-four bladder cancer patients who underwent surgical resection between 2018 and 2020 in Zhejiang Provincial People's Hospital were analyzed in this study. Immunohistochemistry was used to evaluate CD3, CD4, CD8, and FoxP3 expression on TILs in the invasive margin of tumor tissue, and the presence of TIL subsets was correlated with the disease-free survival (DFS) of bladder cancer patients. The relationship between clinical-pathological features and DFS were analyzed. A high level of CD3 + TILs (CD3 high TILs) ( P = 0.027) or negative expression of FoxP3 TILs (FoxP3 - TILs) ( P = 0.016) was significantly related to better DFS in bladder cancer patients. Those with CD3 high FoxP3 - TILs had the best prognosis compared to those with CD3 high FoxP3 + TILs or CD3 low FoxP3 - TILs ( P = 0.0035). Advanced age [HR 4.57, (1.86-11.25); P = 0.001], CD3 low TILs [HR 0.21, (0.06-0.71); P = 0.012], CD8 low TILs [HR 0.34, (0.12-0.94); P = 0.039], and FoxP3 + TILs [HR 10.11 (1.96-52.27); P = 0.006] in the invasive margin were associated with a worse prognosis (DFS) by multivariate analysis. In conclusion, we demonstrated that CD3 high , FoxP3 - , and CD3 high FoxP3 - TILs in the invasive margin were significantly associated with better DFS. CD8 high and CD4 high TILs in the invasive margin tended to predict better DFS in bladder cancer. Patients with CD4 high CD8 high TILs in the invasive margin were likely to have a better prognosis.
Subject(s)
Carcinoma, Transitional Cell , Urinary Bladder Neoplasms , Humans , Lymphocytes, Tumor-Infiltrating/metabolism , Prognosis , Urinary Bladder , Urinary Bladder Neoplasms/surgery , Urinary Bladder Neoplasms/metabolism , CD8-Positive T-LymphocytesABSTRACT
Accumulating evidence suggests the pathogenic role of immunity and metabolism in diabetic kidney disease (DKD). Herein, we aimed to investigate the effect of complement factor B (CFB) on lipid metabolism in the development of DKD. We found that in patients with diabetic nephropathy, the staining of Bb, CFB, C3a, C5a, and C5b-9 was markedly elevated in renal tubulointerstitium. Cfb-knockout diabetic mice had substantially milder tubulointerstitial injury and less ceramide biosynthesis. The in vitro study demonstrated that cytokine secretion, endoplasmic reticulum stress, oxidative stress, and cell apoptosis were ameliorated in HK-2 cells transfected with siRNA of CFB under high-glucose conditions. Exogenous ceramide supplementation attenuated the protective effect of CFB knockdown in HK-2 cells, while inhibiting ceramide synthases (CERS) with fumonisin B1 in CFB-overexpressing cells rescued the cell injury. CFB knockdown could downregulate the expression of NF-κB p65, which initiates the transcription of CERS3. Furthermore, C3 knockdown abolished CFB-mediated cytokine secretion, NF-κB signaling activation, and subsequently ceramide biosynthesis. Thus, CFB deficiency inhibited activation of the complement alternative pathway and attenuated kidney damage in DKD, especially tubulointerstitial injury, by inhibiting the NF-κB signaling pathway, further blocking the transcription of CERS, which regulates the biosynthesis of ceramide. CFB may be a promising therapeutic target of DKD.