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Supplemental Digital Content is Available in the Text.This retrospective interventional case series study reports the use of an inverted internal limiting membrane flap with autologous blood for coverage after air–fluid exchange, which may promote anatomical and functional recovery in treating extensive retinal detachment.

With the increasing integration of renewable energy sources into distribution networks, short-term voltage stability (STVS) has become a prominent issue. Considering grid impedance and maximum rated current, a novel dynamic voltage support (DVS) control strategy for inverter-interfaced distributed generators (IIDGs) is proposed in this article for improving STVS. Furthermore, the impact mechanism of load dynamics and load spatial distribution on the STVS-support strategy are elucidated. For maximizing the STVS of the system, due to the difficulty of obtaining analytical closed-form expressions, a practical optimization method for multi-IIDG is proposed for the optimal control parameters. The optimization is solved alternately based on the time-domain simulation (TDS) and the simultaneous perturbation stochastic approximation (SPSA) algorithm. The STVS is evaluated by a proposed quantitative indicator. According to the operation state of the system, the control strategy can be adjusted online. The effectiveness of the proposed method is verified based on two test systems. Compared with other DVS capabilities, the STVS is further improved by considering distributed dynamic loads. The applicability and computational efficiency of the proposed method are discussed under various key conditions.

The existing fault diagnosis methods can achieve good results when various status fault data are available. However, the construction of the diagnosis model is often unachievable in the actual application because only normal data are available, which is actually a few-shot fault diagnosis problem. Therefore, a novel intelligent few-shot fault diagnosis method of rotating machinery based on the convolutional neural network (CNN) using virtual samples generated by the mechanism character generative model (MCGM) integrating the generative adversarial network (GAN) is proposed. The distribution pattern of common parameters that reflect the fault category is learned using the GAN and source domain fault data. Then, the normal state data of the target domain is combined with the distribution common parameters to generate virtual samples in target domain based on the MCGM. Moreover, the fault diagnosis model is trained by virtual samples based on the CNN. Finally, the proposed fault diagnosis method is validated using the laboratory bearing data, the industrial data and the public data of the rotating machinery, respectively. The results show that the proposed method achieves an average accuracy of 93.38% in the diagnostic task, exhibiting at least 4.56% better performance than other comparison methods.

With local synchronous generators in receiving-end grids being replaced by multi-infeed line-commutated converter-based (LCC) high-voltage direct currents (HVDCs), the dynamic voltage supportability of the power grid decreases. Moreover, the reactive power consumption of LCC-HVDCs during the recovery process brings risks to voltage stability. Hence, the transient control of LCC-HVDCs should be optimized coordinately to support short-term voltage stability under credible contingencies. In this paper, the dynamic reactive power characteristics between AC/DC systems are derived mathematically. Based on the coupling mechanism among the voltage-dependent current order limiter (VDCOL), AC dynamic voltage, and HVDC power recovery, an “autonomous-synergic” optimization strategy incorporating short-term voltage stability constraints is proposed for multi-infeed LCC-HVDCs. To handle the problem of large-scale differential-algebraic equations (DAEs), the optimization is iteratively solved based on time-domain simulation (TDS) and trajectory sensitivities. The stability is quantified by an indicator and the trajectory sensitivity analysis is utilized to relax stability constraints. The effectiveness and feasibility of the proposed methods are verified with a benchmark system and a real system in China. The short-term voltage stability under all credible contingencies can be guaranteed, while the total power recovery of LCC-HVDCs is improved.

The continuing emergence of SARS-CoV-2 variants highlights the need to update COVID-19 vaccine compositions. However, immune imprinting induced by vaccination based on the ancestral (hereafter referred to as WT) strain would compromise the antibody response to Omicron-based boosters1–5. Vaccination strategies to counter immune imprinting are critically needed. Here we investigated the degree and dynamics of immune imprinting in mouse models and human cohorts, especially focusing on the role of repeated Omicron stimulation. In mice, the efficacy of single Omicron boosting is heavily limited when using variants that are antigenically distinct from WT—such as the XBB variant—and this concerning situation could be mitigated by a second Omicron booster. Similarly, in humans, repeated Omicron infections could alleviate WT vaccination-induced immune imprinting and generate broad neutralization responses in both plasma and nasal mucosa. Notably, deep mutational scanning-based epitope characterization of 781 receptor-binding domain (RBD)-targeting monoclonal antibodies isolated from repeated Omicron infection revealed that double Omicron exposure could induce a large proportion of matured Omicron-specific antibodies that have distinct RBD epitopes to WT-induced antibodies. Consequently, immune imprinting was largely mitigated, and the bias towards non-neutralizing epitopes observed in single Omicron exposures was restored. On the basis of the deep mutational scanning profiles, we identified evolution hotspots of XBB.1.5 RBD and demonstrated that these mutations could further boost the immune-evasion capability of XBB.1.5 while maintaining high ACE2-binding affinity. Our findings suggest that the WT component should be abandoned when updating COVID-19 vaccines, and individuals without prior Omicron exposure should receive two updated vaccine boosters.

At this moment, non-aqueous rechargeable lithium-oxygen batteries (LOBs) with extremely high energy density are regarded as the most viable energy storage devices to potentially replace petroleum. One of the most crucial impediments to their implementation has been ensuring facile oxygen availability. Moreover, as semi-sealed systems, LOBs have confronted challenges including oxygen impurities, product degradation, anode corrosion, frequent side reactions, and mediocre cycling performance. In this work, utilizing the physical adsorption of porous (micro-, meso- and macro-porous) solid carbon materials, we incorporate an oxygen storage layer (OSL) with reversible oxygen ad/desorption capabilities into a LOB to develop novel fully-sealed lithium-oxygen batteries (F-S-LOBs). The results demonstrate mesoporous carbons exhibit optimal oxygen adsorption/desorption kinetics, rendering them highly suitable for F-S-LOBs without developing complex oxygen-permeable membranes or carrying oxygen tanks. The OSL fabricated with mesoporous carbon can sustain battery charge/discharge at various current densities with exceptional cycling performance. Additionally, we provide approximate pore size guidelines for oxygen storage materials to aid future research. This study is anticipated to offer a new robust research direction for metal-air batteries and to forge a new path toward promoting the commercialization and development of this technology.

ABSTRACTHydrogenated diamond-like carbon (DLC: H) films were successfully fabricated on the surface of 13Cr super martensitic stainless steel by high-pulsed power chemical vapour deposition. The mechanical and tribological properties of the films related to the substrate bias voltages were investigated. The results showed that the surface hardness and tribological properties of the substrate after DLC film deposition were improved. The DLC films became dense, the grain size and roughness reduced, and the deposition rates increased as the bias voltage increased. In addition, the dense DLC films directly led to high nanohardness and elastic modulus. The H content decreased with an increase in the bias voltage, which may be the primary reason for nanohardness and modulus enhancement. Due to the relatively high H/E* and H2/E*3ratios of films corresponded to high elastic strain and plastic deformation resistances reduced the wear loss, and the localized graphitization on the surface provided solid lubrication.

Hydrogenated diamond-like carbon (DLC: H) films were successfully fabricated on the surface of 13Cr super martensitic stainless steel by high-pulsed power chemical vapour deposition. The mechanical and tribological properties of the films related to the substrate bias voltages were investigated. The results showed that the surface hardness and tribological properties of the substrate after DLC film deposition were improved. The DLC films became dense, the grain size and roughness reduced, and the deposition rates increased as the bias voltage increased. In addition, the dense DLC films directly led to high nanohardness and elastic modulus. The H content decreased with an increase in the bias voltage, which may be the primary reason for nanohardness and modulus enhancement. Due to the relatively high H/E* and H2/E*3ratios of films corresponded to high elastic strain and plastic deformation resistances reduced the wear loss, and the localized graphitization on the surface provided solid lubrication.

In this work, button single cells with Ni-YSZ (anode support) | YSZ (electrolyte membrane) | Gd0.1Ce0.9O1.95 (barrier layer) | La0.6Sr0.4Co0.2Fe0.8O3-?(cathode) structure produced by mass-producing under industrial conditions were operated with dry hydrogen as fuel. In order to simulate single cell unit failure in series stack and local region failure of one cell, fuel gas depletion experiments were carried out in constant current and constant voltage discharge modes, respectively. During the discharging processes, the hydrogen fuel was fed and cut off alternatively for several times with different cut-off time, the output performances were measured to evaluate the stability and healthy of the single cell. The results show that the long time fuel depletion of the cell discharging in constant current mode can directly destroy the cell, it means a cell unit's life in series stack can be affected when suffered fuel depletion. However, the cell discharging in constant voltage mode can keep stable status under fuel depletion condition, it means that the local fuel depletion in a certain cell will not destroy it.

Cation segregation on cathode surfaces plays a key role in determining the activity and operational stability of solid oxide fuel cells (SOFCs). The double perovskite oxide PrBa0.8Ca0.2Co2O5+δ(PBCC) has been widely studied as an active cathode but still suffer from serious detrimental segregations. To enhance the cathode stability, a PBCC derived A-site medium-entropy Pr0.6La0.1Nd0.1Sm0.1Gd0.1Ba0.8Ca0.2Co2O5+δ(ME-PBCC) oxide was prepared and its segregation behaviors were investigated under different conditions. Compared with initial PBCC oxide, the segregations of BaO and Co3O4on the surface of ME-PBCC material are significantly suppressed, especially for Co3O4, which is attributed to its higher configuration entropy. Our results also confirm the improved electrochemical performance and structural stability of ME-PBCC material, enabling it as a promising cathode for SOFCs.

BackgroundEfficient therapy and potential prophylaxis are confounded by current ignorance of the pathogenesis of airway remodelling and blockade in COPD.ObjectiveTo explore the role of the IL-33/ST2 axis in cigarette smoke (CS) exposure-induced airways remodelling.MethodsC57BL/6, BALB/c and IL-1RL1-/-mice exposed to CS were used to establish an animal surrogate of COPD (air-exposed=5~8, CS-exposed=6~12). Hallmarks of remodelling were measured in mice. Cigarette smoke extract (CSE)-induced proliferation and protein production in vitro by fibroblasts in the presence of anti-interleukin-33 (anti-IL-33) or hST2 antibodies were measured. Expression of IL-33 and ST2 and other remodelling hallmarks were measured, respectively, in bronchoalveolar lavage fluid (BALF) (controls=20, COPD=20), serum (controls=59, COPD=90) and lung tissue sections (controls=11, COPD=7) from patients with COPD and controls.ResultsWild-type mice exposed to CS elevated expression of hallmarks of tissue remodelling in the lungs and also in the heart, spleen and kidneys, which were significantly abrogated in the IL-1RL1-/-mice. Fibroblasts exposed to CSE, compared with control, exhibited early cellular translocation of IL-33, accompanied by proliferation and elevated protein synthesis, all inhabitable by blockade of IL-33/ST2 signalling. Expression of IL-33 and ST2 and hallmarks of tissue remodelling were significantly and proportionally elevated in BALF, serum and tissue samples from patients with COPD.ConclusionsExposure to CS induces remodelling changes in multiple organs. The data support the hypothesis that CS-induced lung collagen deposition is at least partly a result of CS-induced IL-33 translocation and release from local fibroblasts.

Structural principles underlying the composition and synergistic mechanisms of protective monoclonal antibody cocktails are poorly defined. Here, we exploited antibody cooperativity to develop a therapeutic antibody cocktail against SARS-CoV-2. On the basis of our previously identified humanized cross-neutralizing antibody H014, we systematically analyzed a fully human naive antibody library and rationally identified a potent neutralizing antibody partner, P17, which confers effective protection in animal model. Cryo-EM studies dissected the nature of the P17 epitope, which is SARS-CoV-2 specific and distinctly different from that of H014. High-resolution structure of the SARS-CoV-2 spike in complex with H014 and P17, together with functional investigations revealed that in a two-antibody cocktail, synergistic neutralization was achieved by S1 shielding and conformational locking, thereby blocking receptor attachment and viral membrane fusion, conferring high potency as well as robustness against viral mutation escape. Furthermore, cluster analysis identified a hypothetical 3rd antibody partner for further reinforcing the cocktail as pan-SARS-CoVs therapeutics.

Electrolyte additives play an important role in suppressing lithium dendrites through tailoring the composition/property of the SEI, however lacking of additives can achieve high performances both in ether and carbonate electrolytes hinders further enhancement of the high voltage lithium-metal batteries. Here, lithium perchlorate (LiClO4) has been presented as an excellent additive to meet the above requirements. An optimized chemical composition of SEI can be achieved through the formation of ionic association. Our results indicate that the LiClO4behaves like a catalyst, which promotes LiTFSI to form a better SEI to inhibit further reaction. Superior coulombic efficiencies and cycling performances were obtained both in ether and carbonate electrolytes. This study paves a new pathway for designing bi-soluble additives for safe lithium metal batteries.

BACKGROUND AND OBJECTIVE:To report the imaging features of different stages of retinal angiomatous proliferation (RAP) on optical coherence tomography angiography (OCTA).PATIENTS AND METHODS:Patients diagnosed with RAP were included in this study. All patients underwent fluorescein angiography (FA), indocyanine green angiography (ICGA), optical coherence tomography (OCT), and OCTA. The OCTA features were illustrated and compared with FA, ICGA, and OCT. OCTA was performed at baseline and after injection of anti-vascular endothelial growth factor (VEGF).RESULTS:A total of 12 eyes of 12 consecutive patients were included. Patients' ages ranged from 57 to 82 years. In all cases, the hot spot lesions found on FA or ICGA were clearly detected on OCTA in the same area (12/12, 100%). Hot spot lesions showed variable patterns. Four patients had multiple hot spot lesions located on the outer retina layer, deep layer, or superior retinal layer. OCTA showed a clearer location and relationship with feeder vessels compared with FA or ICGA. Eight patients had received anti-VEGF therapy 1.75 ± 1.06 times. Follow-up OCTA images demonstrated smaller and fewer hot spot lesions with lesser blood flow signal.CONCLUSIONS:OCTA is a noninvasive, fast imaging modality for detecting microvascular changes, and it provides more detail of the RAP lesion and related vessels than ICGA or FA. OCTA would be a valuable tool for follow-up observation. The OCTA patterns of RAP may be helpful in understanding its pathology.[[Ophthalmic Surg Lasers Imaging Retina. 2020;51:136–144.]

ABSTRACTThe global energy crisis and climate warming are becoming more and more serious. How to reduce energy consumption and environmental pollution to achieve low-carbon manufacturing is an urgent problem to solve. Tool wear leads to the increase of cutting force and cutting power of machine tools obviously. So the influence of tool wear on energy consumption of machine tools cannot be ignored. Firstly, the power of CNC machine tool in cutting stage is divided into standby power, cutting material power and spindle no-load power in the paper. Then, the specific energy consumption prediction model of CNC machine tools based on tool wear is developed. Furthermore, the proposed model is verified with dry milling 45# steel experiments, and the prediction accuracy can reach 98.2% according to material removal rate, spindle speed and tool wear. Finally, the influence of processing parameters and tool wear on specific energy consumption of machine tools is studied. The research is helpful to optimize the processing parameters and tool conditions to reduce the energy consumption of machine tools.

Objective:The present study was designed to investigate the cytoprotective effects of ginsenoside Rg1 (GS-Rg1) against malondialdehyde (MDA)-suppressed proliferation of the mesenchymal stem cells (MSCs) and its possible mechanisms in vitro.Methods:Murine bone marrow-derived MSCs were treated with GS-Rg1 (10, 50, 100mg/L) for 24h before being incubated with MDA in vitro, CFU-Fassay, the cell viability and BrdU incorporation assay were examined, the expression of cyclin-dependent kinase 2 (CDK2), p21 and cyclin E of MSC were examined by Q-RT-PCR and Western blotting.Results:The results showed that the number and size of murine bone marrow MSC colonies, the number of colony-forming cells, methyl thiazolyltetrazolium (MTT) absorbed value greatly and percentage of BrdU-positive cells increased significantly in MSC pretreated with GS-Rg1. GS-Rgl pretreatment markedly decreased the expression level of p21 and increased the expression of CDK2 and cyclin E. GS-Rg1 protects MSCs from MDA-suppressed proliferation.Conclusion:The protective mechanism could be related to its ability to increase the expression of CDK2 and cyclin E, and to reduce the expression of p21.

In this paper, the scheduling problem for hybrid flow shop is investigated with the consideration of the finite buffers. Different from the existing works which focus on the makespan minimisation under the constraints of given intermediate buffer sizes, this paper investigates how to decide the reasonable size of the intermediate buffer. Firstly, the problem is modelled with the design of the accurate and reasonable buffer space without affecting the flow shop production efficiency. Then, a hybrid heuristic method is proposed to reduce the algorithm complexity. Specifically, the buffer size is estimated based on the theory of probability distribution, and the searching for the global optimal solution is processed by using a novel and effective self-adaptive differential evolution algorithm. The proposed algorithm can adjust parameters intelligently for stopping unnecessary iterations as well as avoiding the stagnant situation of the local optimum. Lastly, a wide range of practical scenarios are considered for algorithm evaluation, and the numerical results show that the proposed approach is effective on: 1) reducing the buffer size; 2) guaranteeing the hybrid flow shop efficiency.

The lateral photovoltaic (LPV) effect has attracted much attention for a long time because of its application in position-sensitive detectors (PSD). Here, we report the ultrafast response of the LPV in amorphous MoS2/Si (a-MoS2/Si) junctions prepared by the pulsed laser deposition (PLD) technique. Different orientations of the built-in field and the breakover voltages are observed for a-MoS2films deposited on p-and n-type Si wafers, resulting in the induction of positive and negative voltages in the a-MoS2/n-Si and a-MoS2/p-Si junctions upon laser illumination, respectively. The dependence of the LPV on the position of the illumination shows very high sensitivity (183 mV mm–1) and good linearity. The optical relaxation time of LPV with a positive voltage was about 5.8 μs in a-MoS2/n-Si junction, whereas the optical relaxation time of LPV with a negative voltage was about 2.1 μs in a-MoS2/p-Si junction. Our results clearly suggested that the inversion layer at the a-MoS2/Si interface made a good contribution to the ultrafast response of the LPV in a-MoS2/Si junctions. The large positional sensitivity and ultrafast relaxation of LPV may promise the a-MoS2/Si junction’s applications in fast position-sensitive detectors.

A composite film with gradient structure constructed through infiltrating liquid metal (LM)/Polyvinyl alcohol (PVA) solution into a boron nitride nanosheet/silk fibroin (BNNS/SF) electrospinning film was developed. The gravity driven settling and PVA welding give rise to the gradient distribution of LM, and the LM/BNNS/SF composite film was obtained following the mold pressing. Benefitting from the LM, the LM/BNNS/SF composite film exhibits a highest through-plane thermal conductivity (TC) about 3.24 W/m·K and a highest in-plane TC about 12.53 W/m·K, together with outstanding electromagnetic shielding efficiency, reaching to 75dB in X band. Moreover, the LM/BNNS/SF composite film also exhibits good surface insulativity, exhibiting great potential in electronic packaging material field.

Abrasive waterjet peening is a promising method for surface strengthening and anti-fatigue processing, which has the advantages such as cleanness, high efficiency and low thermal effect. The surface integrity and fatigue performance of the specimens processed by abrasive waterjet peening are still lack of attention to be paid. In this paper, a numerical model was utilized to study the residual stress distribution and the surface roughness of the Ti–6Al–4V specimen surface in abrasive waterjet peening. The validity of the model were then verified by experiments. Moreover, the fatigue performance of the abrasive waterjet peened specimen were investigated numerically, and the fatigue life tests were also conducted under various loading conditions. The effects of different parameters on the surface integrity and the fatigue property were analyzed. The results indicates that higher residual stress can be obtained by implementing high particle velocity and large particle diameter. The fatigue life of the specimen will be decreased when using larger abrasive particles due to the deteriorated surface roughness.

An optical method based on the multiphonon-assisted anti-Stokes-to-Stokes fluorescence intensity ratio (ASFIR) has been developed for temperature sensing. The ASFIR of YAG:Ce is found to exhibit a near linear and monotonic temperature dependence. Based on these properties, a thermometry using the ASFIR technique has been demonstrated in the range extending from 300 to 800 K with a nearly constant sensitivity of 0.07%  K^−1 and a precision of ±2% at 800 K. Also, the conventional dual-Stokes emission bands intensity ratio of YAG:Ce is shown to depend non-monotonically on temperature; thus the suggested ASFIR technique offers an effective method for luminescence thermometry.

Abrasive waterjet machining (AWJ) is one of the fastest growing non-conventional machining methods. However, low pressure and fine abrasive implemented in AWJ precision machining for reducing the surface damage reduce the efficiency. Therefore ultrasonic vibration is considered to apply on the workpiece to improve the machining efficiency. In order to analyze the effect of the vibration on erosion in AWJ machining, smoothed particle hydrodynamics (SPH) is used to simulate the erosion process for avoiding the mesh distortion in finite element method (FEM) when simulating large deformation and high strain rate problems. The results show that the application of ultrasonic vibration can effectively improve the erosion rate due to the dynamics variation of the erosion process.

Dome gas lift is one of the core link in the process of the construction of a large LNG (liquefied natural gas) storage tank. The process of traditional gas lift is relying on the working experience to control the gas pressure inside the storage tank, which has low control precision and poor operability. In this paper, a kind of PID control method was designed through the analysis of the gas lift process and the data was extracted as the feedback parameters by multi-point gas pressure sensors. Simulation was proceeded by the MATLAB software. The results show that, this PID control method can automatically adjust the pressure of the process of gas lift. And it also has fast, stable and reliable control performance. This method has important practical value in improving the control precision of the large LNG storage tank gas lift.

Dome gas lift is the technical difficulties of a large LNG (liquefied natural gas) tanks in the process of construction. The sealing structure is one of the core link in the process of the gas lift. In this paper, the seal structure of large LNG storage tank dome gas lift is studied. A new kind of sealing structure is designed by using gap seal. This paper has carried on the simulation analysis with ANSYS software to verify the feasibility of new type sealing structure. This kind of sealing structure can reduce the friction in the process of gas lift. It also can use the smaller contact area to achieve good sealing effect. The method has important practical value in enhancing the security of gas lift of LNG storage tank dome.

The buffering airbag is one of the most important technologies for the landing impact attenuation of dropped equipments. A designed simplified airbag had been used to study cushion characteristics of self-inflating buffering airbag based on experimental method. Every possible combination of factors and factor levels was considered in the experiment. The influence factors of cushion characteristics were researched through the results. The results show that acceleration and pressure inside the airbag are affected by the initial landing velocity, mass of the load and the initial state of vent orifices. Then the simulation model of airbag was established and validated by experimental results. The simulation results agree very well with the experimental results. The established model can be used for further research of cushion characteristics.

Pattern matching algorithm is a key technology of intrusion defense system in computer network. Based on the pattern matching algorithm AC-BM, This paper proposes an structure of binary tree to express the pattern tree , the structure model of binary tree can reduce the time of forming pattern tree, and then through the using of improved BMHS algorithm of bad character, the algorithm can increase moving distance of pattern tree decrease the matching time, and promote the speed of pattern matching. The experimental data show that, through the improvement of AC-BM algorithm, it indeed can improve the matching speed, achieving good time performance.

We do a new Li-ion battery evaluation research on the effects of cell resistance and polarization on the energy loss in batteries based on thermal property and heat generation behavior of battery. Series of 18650 cells with different capacities and electrode materials are evaluated by measuring input and output energy which change with charge-discharge time and current. Based on the results of these tests, we build a model of energy loss in cells' charge-discharge process, which include Joule heat and polarization heat impact factors. It was reported that Joule heat was caused by cell resistance, which included DC-resistance and reaction resistance, and reaction resistance could not be easily obtained through routine test method. Using this new method, we can get the total resistance R and the polarization parameter e. The relationship between R, e, and temperature is also investigated in order to build a general model for series of different Li-ion batteries, and the research can be used in the performance evaluation, state of charge prediction and the measuring of consistency of the batteries.

We do a new Li-ion battery evaluation research on the effects of cell resistance and polarization on the energy loss in batteries based on thermal property and heat generation behavior of battery. Series of 18650 cells with different capacities and electrode materials are evaluated by measuring input and output energy which change with charge-discharge time and current. Based on the results of these tests, we build a model of energy loss in cells' charge-discharge process, which include Joule heat and polarization heat impact factors. It was reported that Joule heat was caused by cell resistance, which included DC-resistance and reaction resistance, and reaction resistance could not be easily obtained through routine test method. Using this new method, we can get the total resistance Rand the polarization parameter ?. The relationship between R, ?, and temperature is also investigated in order to build a general model for series of different Li-ion batteries, and the research can be used in the performance evaluation, state of charge prediction and the measuring of consistency of the batteries.

Having an insight on the fluid field in AWJ machining is of important significance but the direct observation and measurement can be hardly implemented. Thus a 3D simulation of the fluid field in AWJ has been undertaken using FLUENT 6.3. The pressure and velocity distribution results on the impacted surface under different impact angle conditions are acquired and analyzed. The influence of the impact angle on the characteristics such as the symmetry of the distribution, position of the maximum value and the stagnation effect is highly concerned. In addition, an experiment under the similar conditions of the simulation is conducted and the results are compared with that of the simulation.

A series of Ni-Cu oxide solid solutions and Ce0.8Sm0.2O1.9 (SDC) electrolyte were synthesized by nitrate-citric acid method. Then Ni-Cu/SDC composite anode materials were prepared. Meanwhile, their microstructure and performance were also tested. The results showed that the single solid oxides fuel cell(SOFC) employing Cu0.4Ni0.6O as the anode, and using hydrogen as fuel had the best electrochemical performance. The maximal power density could reach 126mW.cm-2 at 700℃.

We report on a monitoring technique for nitrogen dioxide based on broadband absorption spectroscopy using a blue light-emitting diode (LED) operating around 465 nm. The technique is suited for real-time measurements of nitrogen dioxide due to the use of a straightforward data evaluation method, limited interference from other gases, and a low degree of complexity compared with other real-time optical detection techniques having the same precision. Additionally, the use of a LED can reduce the cost of nitrogen dioxide monitoring. Real-time measurements of nitrogen dioxide concentration were demonstrated at atmospheric pressure, which is of great interest for industrial nitrogen dioxide emission monitoring; a detection limit of about 3 ppm using a 50-cm-long gas cell with 2 s integration time was achieved.

ABSTRACTTo evaluate the potentiality of applying gene therapy to bacterial infections, especially for preventing infection in high-risk patients, we investigated protection of mice from challenge with lethal Escherichia coliinfection by adeno-associated virus serotype 2 (AAV2)-mediated gene transfer of a chimeric BPI23-Fcγ1 gene, which consisted of human bactericidal/permeability-increasing protein (BPI) gene encoding the functional N terminus (amino acid residues 1 to 199) of human BPI and an Fcγ1 gene encoding the Fc segment of human immunoglobulin G1. Here we show that the target protein that was expressed and secreted into the serum of the gene-transferred mice demonstrated the activity of a neutralizing endotoxin, killing E. coliand mediating opsonization. After lethal E. coliinfection, the count of bacteria and the levels of endotoxin and proinflammatory cytokines in the gene-transferred mice were decreased. The survival rate of BPI23-Fcγ1 gene-transferred mice markedly increased, especially in conjunction with antibiotics. Our data suggest that AAV2-mediated chimeric BPI23-Fcγ1 gene delivery could potentially be used clinically for the protection and treatment of infection with gram-negative bacteria in high-risk individuals.

Receptor recognition and subsequent membrane fusion are essential for the establishment of successful infection by SARS-CoV-2. Halting these steps can cure COVID-19. Here we have identified and characterized a potent human monoclonal antibody, HB27, that blocks SARS-CoV-2 attachment to its cellular receptor at sub-nM concentrations. Remarkably, HB27 can also prevent SARS-CoV-2 membrane fusion. Consequently, a single dose of HB27 conferred effective protection against SARS-CoV-2 in two established mouse models. Rhesus macaques showed no obvious adverse events when administrated with 10 times the effective dose of HB27. Cryo-EM studies on complex of SARS-CoV-2 trimeric S with HB27 Fab reveal that three Fab fragments work synergistically to occlude SARS-CoV-2 from binding to the ACE2 receptor. Binding of the antibody also restrains any further conformational changes of the receptor binding domain, possibly interfering with progression from the prefusion to the postfusion stage. These results suggest that HB27 is a promising candidate for immuno-therapies against COVID-19.

Understanding the dynamic surface reconstruction is of vital importance for the development of oxygen evolution reaction (OER) electrocatalysts. Herein, we report FeOOH decorated NiMoO4nanowires as OER pre-catalysts. In-situRaman spectroscopy elucidates that modified NiMoO4undergoes fast reconstruction, including significant Mo leaching and simultaneous formation of Ni(Fe)OOH intermediates, which are determined as the real active species toward OER. Rapid and deep reconstruction results in amorphous nanowires with uniform Fe distribution and great size expansion. Impressively, the reconstructed pre-catalyst exhibits outstanding catalytic activity, ultra-low overpotential and extraordinary long-term stability under high current densities. Our work provides a facile and effective surface engineering approach of pre-catalysts and highlights the evolution of self-reconstruction chemistry for accelerating the kinetics of OER.

The prevalence of allergic diseases is increasing worldwide. Currently available biologic therapies have substantially enriched the therapeutic opportunities in the field of allergic diseases such as asthma, atopic dermatitis, and rhinosinusitis. The aims of the present review are to focus on the current status of development of monoclonal antibodies targeting the cytokines and immunoglobulin, which are involved in the pathogenesis of allergic diseases, and to discuss the clinical effects of these antibodies.