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Current problems of existing heavy metal-removing technologies, especially for nanomaterials-based ones, are typically single metal ion-specific, high-cost and collected difficult. Herein, facile modification of commercial sulfur creates a versatile adsorbent platform to address challenges. The versatile adsorbent can be easily prepared through solvothermal treatment of a saturated commercial sulfur solution, followed by water precipitation on a commercial foam that eliminates the need for separation. Interestingly, the solvothermal treatment endows the resulting nanosulfur with sulfate acid groups (hard Lewis base), sulfur anions (soft base), and sulfite groups (borderline base), promising the coordination of all types of heavy metal ions (Lewis acids). As such, this versatile adsorbent with well-distributed adsorption sites exhibits highly effective heavy metal adsorption capacity towards diverse heavy metal ions for both single-component and multi-component adsorption, including soft, hard, borderline Lewis metal ions, with ultra-high adsorption ability (e.g., 903.79 mg g-1 for Cu2+). These findings highlighted the potential of this low-cost sulfur-based adsorbent to address the arising challenges in ensuring clean water.
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Electron ptychography has emerged as a popular technology for high-resolution imaging by combining the high coherence of electron sources with the ultra-fast scanning electron coil. However, the limitations of conventional pixelated detectors, including poor dynamic range and slow data readout speeds, have posed restrictions in the past on conducting electron ptychography experiments. We used the Gatan STELA pixelated detector to capture sequential diffraction data of monolayer two-dimensional (2D) materials for ptychographic reconstruction. By using the pixelated detector and electron ptychography, we demonstrate the observation of the radiation damage at atomic resolution in Transition Metal Dichalcogenides (TMDs).
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Developing advanced electrocatalysts toward the oxygen evolution reaction (OER) has always been recognized as the key challenge for green hydrogen production via water electrolysis due to the commonly required high OER overpotential. In this work, we report a branched FeCo-based hydroxide nanotube array (Fe-CoCH NT) synthesized by an ambient Fe-modification strategy, which could be used as a monolithic electrode for efficient OER catalysis. Its OER performance was even comparable to that of RuO2 with a low overpotential of 290 mV to attain a current density of 10 mA cm-2 due to its unique branched nanotube array structure and intrinsic high catalytic activity. Moreover, an acid-base hybrid electrolysis system was built based on this catalyst and an FeCo-based phosphide nanotube array electrode. By collecting electrochemical neutralization energy, this system just needs an ultralow cell voltage of 0.97 V to attain a current density of 10 mA cm-2 with a large decrease in energy consumption of 41.9% compared to traditional alkaline water splitting systems.
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Lithium-oxygen batteries (LOBs) with a theoretical energy density of up to 3500 Wh kg-1 hold a promise for the next-generation high-energy-density batteries. However, the slow oxygen reduction/evolution kinetics at the cathode limits the performance of Li-air batteries. The rational design of efficient catalysts is essential for the improvement of oxygen electrode reaction kinetics. Herein, we report a facile strategy to co-dope N and P atoms simultaneously into Ti3C2Tx (NP-Ti3C2Tx) MXene via an electrostatic self-assembly approach. The co-doped NP-Ti3C2Tx layers expose abundant active sites, providing more space for accommodating the formed Li2O2. Moreover, the N and P co-doping facilitates efficient electron transport in Ti3C2Tx MXene. The LOB with NP-Ti3C2TX catalyst delivers a high discharge capacity of 24,940 mAh/g at 1000 mA g-1. At a cut-off capacity of 1000 mAh/g, this battery runs continuously for 159, 276, 185, and 229 cycles at current densities of 1000, 2000, 3000, and 5000 mA g-1, respectively. Theoretical calculations unveil that N and P co-doping enables lower ηORR and ηOER of only 0.26 V and 0.13 V on Ti3C2Tx MXene, respectively. This work offers a feasible approach for constructing efficient MXene electrocatalysts for Li-air batteries.
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Solid-state Li batteries employing Li-metal anodes and solid Li/Li1.3Al0.3Ti1.7(PO4)3 (LATP) electrolytes have emerged as promising next-generation energy storage devices due to their high energy density and safety. However, their performance is seriously limited by the irreversible reactivity of LATP with the Li-metal anode and the poor solid-solid interfacial contact between them, which result in relatively low ionic conductivity at the interface. The present work addresses these issues by presenting a method for modifying the Li/LATP interface in situ by applying 2-(trimethylsilyl) phenyl trifluoromethanesulfonate (2-(TMS)PTM) as a new type of electrolyte additive between the Li anode and the LATP electrolyte when assembling the battery, and then forming a uniform and thin interfacial layer via redox reactions occurring during the application of multiple charge-discharge cycles to the resulting battery. As a result of the significantly improved chemical compatibility between the Li anode and the LATP electrolyte, an as-assembled battery delivers a high reversible capacity of 165.7 mAh g-1 and an outstanding capacity retention of 86.2% after 300 charge-discharge cycles conducted at a rate of 0.2C and a temperature of 30 °C. Accordingly, this work provides a new strategy for developing advanced solid-state Li metal batteries by tailoring the interface between the Li anode and the solid electrolyte.
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Lithium metal is deemed a promising anode material for the next-generation batteries with high specific energy. Unfortunately, the growth of Li dendrites and infinite volume change during cycling, caused by the "hostless" feature of metallic Li, have posed a great challenge to the commercialization of Li metal anode. The introduction of appropriate host materials for Li metal is highly desirable. In this work, a N, P dual-doped 3D carbon derived from low-cost quantitative filter paper (NPCQP) is designed and fabricated for direct using as a host for Li metal anode. The resulting NPCQP host achieves a high deposition/stripping Coulombic efficiency of above 97.5 % with a low nucleation overpotential. Moreover, the NPCQP@Li symmetric cells enable an excellent long-term cycling performance (1000 h) with an ultralow voltage hysteresis (12 mV) and stable interface behavior. When paired with the commercial LiFePO4 cathode, the full cell with NPCQP@Li anode displays impressive long-term cyclic stability and rate capability, outperforming the counter cell with bare Li anode. This contribution sheds light on the rational design of viable host for practical lithium metal anodes.
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For underwater vehicles, the state of charge (SOC) of battery is often used to guide the optimal allocation of energy. An accurate SOC estimation can improve work efficiency and reliability of underwater vehicles. Model-based SOC estimation methods are still mainstream routes used in practical applications. Hence, accurate battery models are highly desirable, which depends not only on the circuit structure but also on the circuit parameters. Four-parameter identification algorithms, offline mechanism-based and least squared (LS) methods, as well as online recursive least-squares with forget factor (FFRLS) and extended Kalman filter (EKF) methods were analyzed in terms of SOC estimation under three different conditions. The results revealed that in the case without any disturbance, the predicted SOCs based on four-parameter identification circuits fitted well with the reference. Moreover, it is remarkable that the LS offline methods work better than the FFRLS online routes. In addition, the robustness has also been accessed through the other two conditions, i.e., measurement data with disturbance and initial SOC value with deviation. The results showed that maximum errors of SOC estimation based on the EKF approach are significantly lower than those of the other methods, and the values are 0.51% and 0.20%, respectively. Thus, the circuit model based on the EKF parameter identification approach possessed a stronger anti-interference performance during the SOC estimation process. This research can provide corresponding theoretical support on ECM parameter identification for lithium-ion batteries in underwater vehicles.
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Objective: To investigate the efficacy of eye movement technique for the treatment of executive dysfunction of patients with stroke. Methods: This was a prospective, single-blinded, randomized, controlled, single-center clinical trial conducted from June 2018 to December 2019 in patients with stroke. The patients were randomized 1:1 to the routine (conventional management) and eye-move group (routine management plus eye movement technique: 5-min goal management training, 5-min computer-aided working memory, and 10 min of inhibitory control training and set conversion training). The intervention lasted 6 weeks, followed by a 4-week follow-up. The primary endpoint was the Behavioral Assessment of the Dysexecutive Syndrome (BADS) score. The secondary endpoints mainly included the Montreal Cognitive Assessment (MoCA), Wisconsin Card Sorting Test (WCST), and modified Barthel Index (MBI) scores. Results: Sixty-four patients were enrolled (32/group). After the 6-week intervention, the BADS and WCST scores of the eye-move group were significantly improved than those of the routine group (all P < 0.05), but the effects were attenuated in certain subscores after follow-up (all P > 0.05). The MoCA and MBI scores of the eye-move group were significantly higher, and the reaction time was significantly lower than those of the routine group at 4 weeks after the intervention (all P < 0.05). After follow-up, the MBI scores of the eye-move group were still higher than that of the routine group (P < 0.001), but there were no differences for MoCA scores and reaction time (both P > 0.05). Conclusion: The eye movement technique could improve the executive function of patients with stroke. These results have to be confirmed. This was a prospective, single-blinded, randomized, controlled, single-center clinical trial (ChiCTR2000036393). Clinical Trial Registration: [www.chictr.org.cn], identifier [ChiCTR2000036393].
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Developing a cathode material with a stable pore structure and efficient bifunctional activity toward oxygen electrochemistry is the key to achieve practical and high-performance Li-O2 batteries. Here, hierarchically porous MnCo2O4 nanotubes with single- or double-wall architecture are fabricated through a facile electrospinning technique, by adjusting the concentration of the electrospinning solution. The electrochemical measurements indicate that both types of nanotubes possess excellent catalytic abilities toward oxygen reduction and evolution reactions in alkaline aqueous or non-aqueous media. When used as air-electrode catalysts for Li-O2 batteries, both single- and double-wall MnCo2O4 nanotubes show significantly improved electrochemical performance. In particular, the novel double-wall MnCo2O4 nanotubes (DW-MCO-NT), with a high surface area and a large pore volume almost twice as big as the single-wall nanotubes, can offer numerous catalytically active sites as well as sufficient space to deposit discharge products. The DW-MCO-NT based Li-O2 batteries can deliver a maximum discharge capacity of 8100 mA h g-1, with a potential plateau at 2.77 V, and achieve an excellent cyclability over 278 cycles, under strict conditions of 1000 mA h g-1 at 400 mA g-1 within 2.6-4.3 V. Moreover, the XRD and SEM analyses show that the dominant discharge product with a particulate shape is crystal Li2O2 and is prone to being completely decomposed, endowing the MnCo2O4 nanotube-based Li-O2 battery with a long cycle life.
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The common high-capacity cathode Li2C6O6 shows poor cycling performance because of its dissolution in electrolytes. Using morphology control, spherical Li2C6O6 was prepared, and then combined with reduced graphene oxide and modified with an FeF3 coating. This interface engineering inhibited the dissolution of Li2C6O6, and also enhanced its cycling and rate performance.
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Although EphA3 expression has been associated with progression or prognosis in several types of tumors, the role of EphA3 in hepatocellular carcinoma (HCC) remains unknown. This study sought to investigate the clinicopathological and prognostic relevance of EphA3 expression in HCC as well as the underlying mechanisms responsible. EphA3 protein was mainly localized within the cytoplasm and at the cell membrane. High EphA3 expression was correlated with tumor size, tumor grade, metastasis, venous invasion and AJCC TNM stage (P<0.05), and patients with high levels of EphA3 expression were at a significantly increased risk for shortened survival time (P<0.05). In vitro, the downregulation of EphA3 expression decreased the invasive capacity of HCC cells via the regulation of VEGF. EphA3 may represent a novel candidate marker for patient prognosis as well a molecular target for HCC therapy.
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Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Pronóstico , Proteínas Tirosina Quinasas Receptoras/genética , Anciano , Biomarcadores de Tumor/genética , Carcinoma Hepatocelular/patología , Progresión de la Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Invasividad Neoplásica/genética , Estadificación de Neoplasias , Receptor EphA3 , Factor A de Crecimiento Endotelial Vascular/genéticaRESUMEN
BACKGROUND/AIMS: The present study was aimed to investigate lumican expression in and correlation with severity of pancreatic ductal adenocarcinoma (PDA). METHODOLOGY: We assessed mRNA expression and protein localization (using immunohistochemistry) in PDA samples collected from 260 patients. Additionally, we compared lumican expression with expression of Ki-67, VEGF and mutated p53 proteins, which are markers of cancer progression. RESULTS: Expression levels of lumican mRNA and protein in cancer tissue were significantly higher than those in tumor-adjacent tissue (t=5.69, p<0.05). The stromal expression of lumican in poorly differentiated cases was significantly higher at stage T4 than stage T2-3 (χ²=21.06, p<0.05); similarly, the stromal expression of lumican was significantly higher in TNM stage III-IV than in stage I-Il (χ²=17.01, p<0.05). Additionally, expression of Ki67 was higher in poorly differentiated cases than in highly-moderately differentiated cases (χ²=13.06, p<0.05). Finally, in highly-moderately differentiated samples, stromal expression of lumican was negatively correlated with expression of Ki-67, VEGF and mutated P53 (p<0.05). CONCLUSIONS: Lumican expression is higher in pancreatic ductal adenocarcinoma than in tumor-adjacent tissue, and the correlation of lumican expression with TNM stage in poorly differentiated samples, in contrast with its negative correlation with expression of Ki-67, VEGF and mutated P53 mutation in highly-moderately differentiated samples.
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Adenocarcinoma/química , Carcinoma Ductal Pancreático/química , Proteoglicanos Tipo Condroitín Sulfato/análisis , Sulfato de Queratano/análisis , Neoplasias Pancreáticas/química , Adenocarcinoma/patología , Adulto , Anciano , Carcinoma Ductal Pancreático/patología , Proliferación Celular , Proteoglicanos Tipo Condroitín Sulfato/genética , Femenino , Genes p53 , Humanos , Inmunohistoquímica , Sulfato de Queratano/genética , Antígeno Ki-67/análisis , Lumican , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias Pancreáticas/patología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor A de Crecimiento Endotelial Vascular/análisisRESUMEN
MicroRNAs exert regulatory effects on a number of genes, thereby contributing to both physiological and pathological processes. The functions of microRNAs in tumorigenesis are becoming increasingly clear. In the present study, we investigated the role of microRNA-125b (miR125b), previously implicated in prostate and breast cancer, in gastric cancer, particularly regarding proliferation and apoptosis of gastric cancer cells. The expression of miR125b was measured in 50 samples of gastric cancer tissues and corresponding para-cancerous tissues by real-time PCR. The levels of miR125b expression in the gastric cancer tissues were significantly higher compared to the adjacent normal tissues (P<0.05). To begin to understand how the increased expression of miR125b may promote gastric cancer, the miR125b mimic was transfected into the gastric cancer cell line, HGC27, for the determination of proliferation (CCK8) and apoptosis (Annexin V) by flow cytometry. The results demonstrated that the proliferation significantly increased and apoptosis significantly decreased in the HGC27 cells following transfection with the miR125b mimic, compared to the untreated and scrambletreated controls (P<0.05). Thus, miR125b may act as an oncogene in gastric cancer by dysregulating gastric cell proliferation and apoptosis.
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Adenocarcinoma/genética , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , Neoplasias Gástricas/genética , Adenocarcinoma/metabolismo , Apoptosis/genética , Línea Celular Tumoral , Proliferación Celular , Expresión Génica , Humanos , Neoplasias Gástricas/metabolismoRESUMEN
We synthesized a simple fluorescent receptor 3 bearing two boronic acid groups as recognition sites. The recognition behaviour of receptor 3 towards various anions was evaluated in THF/H(2)O (1:1, v/v) solution. Receptor 3 showed high selectivity for iodide among a series of anions. Fluorescence spectroscopy and computational calculations revealed that the electrostatic interaction played a crucial role in its high selectivity for iodide.
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Yoduros/metabolismo , Receptores de Superficie Celular/metabolismo , Agua/química , Modelos Moleculares , Soluciones , Espectrometría de Fluorescencia , Electricidad EstáticaRESUMEN
For the efficient detection of toxic trace metal ions, two pyrenyl-appended triazole-based d-ribose fluorescent chemosensors 6 and 7 were prepared and their fluoroionophoric properties toward transition metal ions were investigated. Chemosensors 6 and 7 exhibit highly selective recognition toward Hg(2+) ion among a series of tested metal ions in CH(2)Cl(2)/MeOH solution. The association constants of 6 and 7 are calculated to be 1.73 × 10(5)M(-1) and 4.44 × 10(5)M(-1), respectively. Both 6 and 7 formed complexes with the Hg(2+) ion at a 1:1 ligand-to-metal ratio with a detection limit of 10-15 µM Hg(2+). Computational analysis demonstrated that the Hg(2+) ion occupied the coordination center of 6 with N(2) and N(3) atoms in two triazole groups, thus separating and distorting the two parallel pyrenes away from each other.
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Técnicas de Química Analítica/instrumentación , Colorantes Fluorescentes/química , Mercurio/análisis , Pirenos/química , Ribosa/química , Triazoles/química , Modelos Moleculares , Conformación Molecular , Espectrometría de FluorescenciaRESUMEN
BACKGROUND & AIMS: Present therapy for chronic hepatitis B attains control only in limited proportions. Small interfering RNA (siRNA) offers a new tool with potential therapeutic applications for hepatitis B virus (HBV). Given the importance of sequence identity in the effectiveness of siRNA and the heterogeneity of HBV sequences among different isolates, a short hairpin RNA (shRNA)-expressing plasmid, pSuper/HBVS1, was developed to target a region conserved among major HBV genotypes and assess its effectiveness control of HBV. METHODS: HBV replication-competent plasmid was cotransfected with pSuper/HBVS1 to HuH-7 cells or to mice. The levels of viral proteins, RNA, and DNA were examined in transfected cells and animals. The effects of pSuper/HBVS1 on clinical isolates with genotypes B and C were also determined. RESULTS: pSuper/HBVS1 significantly decreased levels of viral proteins, RNA, and DNA for HBV genotype A in cell culture and in mice. Comparable suppressive effects were observed on clinical isolates of genotypes B and C. A clone with a silent mutation in the target region was identified from a patient with genotype C. This mutant revealed diminished sensitivity to pSuper/HBVS1 and could be selected out in the presence of pSuper/HBVS1 in cell culture. CONCLUSIONS: These findings indicated that shRNA could suppress HBV expression and replication for genotypes A, B, and C, promising an advance in treatment of HBV. However, the emergence of resistant mutants in HBV quasispecies should be considered.
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Farmacorresistencia Viral/genética , Virus de la Hepatitis B/genética , Mutación , Interferencia de ARN , Animales , Secuencia de Bases , Línea Celular , Expresión Génica/efectos de los fármacos , Genotipo , Virus de la Hepatitis B/fisiología , Humanos , Ratones , Ratones Endogámicos C57BL , ARN Interferente Pequeño/farmacología , Transfección , Replicación Viral/efectos de los fármacosRESUMEN
Previous reports debated the effects of differentiation on adenoviral vector (AdV) transduction efficiency and Coxsackie-adenovirus receptor (CAR) expression. This prompted us to investigate the efficiency of AdV transduction and CAR expression in human mesenchymal stem cells (hMSCs) and their differentiated progeny. Current results revealed high efficiency (>90%) of AdV transduction and a consistent level of CAR expression in hMSCs by the use of AdV carrying the enhanced green fluorescent protein reporter gene. Competition of CAR with blocking monoclonal antibody RmcB resulted in a reduction in transduction efficiency, indicating the CAR involvement in transduction of hMSCs. The cells were then induced to differentiate into bone, fat, or neural cells, and results demonstrated that the differentiation was accompanied with a consistent decline in AdV transduction and a decrement in CAR expression. Cells were infected with AdV and then induced into differentiation, and results demonstrated that transduced cells preserved differentiation potentials and still had transgene expression in a subpopulation of cells for 4 weeks and even in tested lineage-specific differentiation. According to the present investigation, undifferentiated hMSCs can serve as a gene-delivering system, and gene transfer into hMSCs before differentiation can resolve the difficulties in transduction of their differentiated progeny.