Search

Due to waning immunity and protection against infection with SARS-CoV-2, a third dose of a homologous or heterologous COVID-19 vaccine has been proposed by health agencies for individuals who were previously primed with two doses of an inactivated COVID-19 vaccine.We did a randomised, open-label, controlled trial to evaluate the safety and immunogenicity of heterologous boost immunisation with an orally administered aerosolised adenovirus type-5 vector-based COVID-19 vaccine (Ad5-nCoV) in Chinese adults (≥18 years old) who had previously received two doses of an inactivated SARS-CoV-2 vaccine-Sinovac CoronaVac. Eligible participants were randomly assigned (1:1:1) to receive a heterologous booster vaccination with a low dose (1·0 × 10Between Sept 14 and 16, 2021, 420 participants were enrolled: 140 (33%) participants per group. Adverse reactions were reported by 26 (19%) participants in the low dose group and 33 (24%) in the high dose group within 14 days after the booster vaccination, significantly less than the 54 (39%) participants in the CoronaVac group (p0·0001). The low dose group had a serum NAb GMT of 744·4 (95% CI 520·1-1065·6) and the high dose group had a GMT of 714·1 (479·4-1063·7) 14 days after booster dose, significantly higher than the GMT in the CoronaVac group (78·5 [60·5-101·7]; p0·0001).We found that a heterologous booster vaccine with an orally administered aerosolised Ad5-nCoV is safe and highly immunogenic in adults who have previously received two doses of CoronaVac as the primary series vaccination.National Natural Science Foundation of China and Jiangsu Provincial Key Research and Development Program.

The demonstration of batch-to-batch consistency is indispensable for quality control of vaccines. We conducted a randomized, double-blind, parallel-controlled trial to evaluate the immunogenicity consistency of a single shot of Ad5-nCoV in healthy adults who had not previously received any COVID-19 vaccine. All eligible participants were randomly assigned equally to receive one of the three consecutive batches of Ad5-nCoV (5 × 1010 viral particles/vial, 0.5 mL). The primary endpoint was geometric mean titers (GMTs) of serum SARS-CoV-2 receptor-binding domain (RBD)-specific IgG on day 28 post-vaccination. One thousand fifty participants were enrolled, with 350 (33%) participants per group. On day 28 post-vaccination, GMTs in three groups were 78.3 binding antibody units (BAU)/mL (95% CI 70.3–87.3), 82.9 BAU/mL (73.9–92.9), and 78.8 BAU/mL (70.2–88.4), respectively. The two-sided 95% CIs for the GMT ratios between each pair of batches were all between 0.67 and 1.5. The highest incidence of solicited adverse reactions within 7 days post-vaccination was reported by batch 3 recipients (23.1% versus 15.1% in batch 1 recipients and 14.6% in bath 2 recipients; p = 0.0039). None of the serious adverse events were related to vaccination. Immunogenicity consistency between consecutive batches of Ad5-nCoV was well established in adults. This trial was registered with ClinicalTrials.gov (NCT05313646).

We present timing solutions of PSR B0950+08, using 14 years of observations at Nanshan 26-m Radio Telescope of Xinjiang Astronomical Observatory. The braking index of PSR B0950+08 varies from --367 392 to 168 883, which shows an oscillation with large amplitude ($\sim 10^5$) and uncertainty. Considering the variation of braking indices and the most probable kinematic age of PSR B0950+08, a model withe long-term magnetic field decay modulated by short-term oscillations is proposed to explain the timing data. With this magnetic field decay model, we discuss the spin and thermal evolution of PSR B0950+08. The uncertainties of its age are also considered. The results show that three-component oscillations are the more reasonable for the spin-frequency derivative distributions of PSR B0950+08, and the initial spin period of PSR B0950+08 must be shorter than $97\rm\ ms$ when the age is equal to the lower bound of its kinematic age. The standard cooling model could explain the surface temperature of PSR B0950+08 with its most probable kinematic age. Vortex creep heating with a long-term magnetic field decay could maintain a relatively high temperature at the later stages of evolution and explain the thermal emission data of old and warm pulsars. Coupling with the long-term magnetic field decay, an explanation of the temperature of PSR B0950+08 with roto-chemical heating needs an implausibly short initial rotation period ($P_0 \lesssim 17\rm{ ms}$). The spin and thermal evolution of pulsars should be studied simultaneously. Future timing, ultraviolet or X-ray observations are essential for studying the evolution and interior properties of pulsars., Comment: Accepted for publication in MNRAS

Objectives: To investigate the usefulness of diffusion weighted imaging (DWI) and arterial spin labeling (ASL) for predicting final infarct volume in patients with acute atherothrombotic subtype cerebral infarction (AT-type stroke). Methods: The data of 77 patients with AT-type stroke were retrospectively analyzed. ASL and DWI values of minimum apparent diffusion coefficient (minADC), mean ADC (meanADC), minimum cerebral blood flow (minCBF), and mean CBF (meanCBF) of the infarction lesions were measured. Changes in cerebral infarction volume (ΔVolume) were determined by DWI reexamination on the 7th day after onset. Correlations of ADC and CBF with ΔVolume were analyzed. Receiver operating characteristic (ROC) curve analysis was used to determine the usefulness of ADC and CBF values for predicting final infarct volume. Results: There was significant difference in the distribution of the ΔVolume in AT-type stroke (P < 0.0001). The ADC and minCBF values were negatively correlated with the infarct ΔVolume (P < 0.05); meanCBF and ΔCBF were not correlated with ΔVolume. When minADC was ≤0.303 × 10−3 mm2/s, minCBF1.5 ≤2.415 mL/100 g/min, or minCBF2.5 ≤4.25 mL/100 g/min, ΔVolume was likely to be large. The ROC curve showed highest predictive value for minADC and minCBF. Conclusions: Distinctive patterns of quantitative ADC and CBF can be used as a simple and rapid method for predicting change of infarction volume in AT-type stroke.

Background. We aimed to present the immediate and long term effect of percutaneous balloon compression (PBC) for idiopathic trigeminal neuralgia (ITN). Methods. ITN patients who underwent PBC for the first time in the past seven years were enrolled. Base line data and immediate postoperative outcomes were collected by reviewing the medical records and long term results. Kaplan-Meier curve, life-table analysis proportional-hazards analysis were utilized to assess the long term results and the likelihood of tic recurrence. Results. 12,797 patients were enrolled. Immediate after the PBC procedure, complete and partial pain relief were achieved in 95.6% and 1.1% patients respectively, with no relief in 1.7 % patients; the common side effects on the affected side of face included the sense loss in 98.9% patients, with 3.8% of them experienced sense loss combined abnormal sense; masseter weakness in 90.6%, herpes eruption in 51.4%, corneal reflex weakness or loss in 12.7% patients. The fewer perioperative complications covered diplopia in 139 patients (1.1%), partial hearing loss in 190 patients (1.5%), vascular complications in 5 patients (0.05%), brainstem hematoma in one patient (0.01%), ischemic stroke in two patients (0.02%), intracranial hemorrhage in 11 patents (0.09%), and intracranial infection in one patient (0.01%) patients. Of three deaths happened in the perioperative period, two died of intracranial hemorrhage, and the other one died of intracranial infection. 5794 (49.2%) patients, who were followed than one year after the procedure, were included in the follow-up study, with the median follow-up period of 7.2 years. Complete and partial pain relief were obtained in 82.9% and 6.8% patients respectively, while the pain recurrence occurred in 8.5% patients. Side effects included sense loss without abnormal sense in 54.3%, with acceptable abnormal sense in 6.0%, and with severe abnormal sense in 2.0% patients. Masseter weakness was reported by 7.5% patients. 96.4% patients were satisfied with the procedure. Conclusion. Our study shows PBC is a safe, simple and effective procedure, with both immediate and long-term success rates, acceptable side effects and fewer deadly complications, should be considered as one of the best choice for the treatment of ITN patients.

A new isobenzofuranone derivative was isolated from Chaenomeles sinensis by using various chromatographic techniques,including silica gel,Sephadex LH-20,MCI-gel resin and RP-HPLC. This compound was determined as 2,2-dimethyl-5-( 2-oxopropyl)-2 H-furo[3,4-h]chromen-7( 9 H)-one( 1) by NMR,MS,IR and UV spectra,and was also evaluated for its antibacterial activity. The results showed that it showed prominent antibacterial activity with MIC90 value of( 53. 7±4. 5) mg·L-1 for methicillin resistant Staphylococcus aureus( MRSA) strain. This value is close to that of levofloxacin [with MIC90 value( 50. 2± 4. 2) mg·L-1].

Purpose This study was conducted to explore the diagnostic value of arterial spin labeling (ASL) combined with diffusion weighted imaging (DWI) in characterizing the spatiotemporal progression of infarct lesions in a rabbit middle cerebral artery occlusion (MCAO) model and predicting the acute cerebral infarction (ACI) volume. Materials and methods Forty-two male rabbits (2.9 ± 0.2 kg body weight) were used in this experimental study. Animals were initially anesthetized by intravenous injection of uratan. There were seven experimental groups with six rabbits in each group. The apparent diffusion coefficient (ADC) and cerebral blood flow (CBF) thresholds were established in the control group (n = 6), which were sacrificed at 12 h, stained for infarct volume, and imaged at each time point. Results The normal ADC and CBF were estimated as 0.90 ± 0.03 × 10−3 mm2/s and 0.68 ± 0.06 mL g−1 min−1, respectively. The viability thresholds of ADC and CBF yielding the lesion volumes (LVs) at 3 h, which best approximated the 2,3,5-triphenyltetrazolium chloride (TTC) infarct volumes at 12 h, were 0.52 ± 0.02 × 10−3 mm2/s (42.2 ± 3% reduction) and 0.33 ± 0.09 mL g−1 min−1 (51.0 ± 11% reduction), respectively. The temporal evolution of the ADC- and CBF-defined LVs showed a significant perfusion/diffusion mismatch up to 1 h (p = 0.001). Conclusion ADC values and ACI volumes were positively correlated, while CBF was negatively correlated, which is supposed to be a reference for predicting ACI volume.

This paper analyses several common transmission pricing methods of marginal cost and embedded cost deeply. It analyses pricing models of several transmission pricing methods, long-run marginal cost (LRMC) method, MW-Mile method, sensitivity method, flow tracing method, contract path method and stamp method. It also gives a comprehensive comparison of characteristics and limitations of these pricing methods, discusses their applicable conditions in aspects of fairness, economic, financial balance, transparency, operability and others, and makes a quantitative research of comparison based on a case, and verifies the results.

Three metal powders of Mg, an Al-Mg alloy (AM) and Al are characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA) techniques. This study focuses on the reactions of the metal powders with flowing steam heated at 600°C, 700°C, 800°C, and 900°C in a transparent pipe furnace. The phases of the solid reaction products are analyzed using XRD, and the residual metal content and ignition delay times are measured. The experimental results revealed that the Mg and AM powders ignite and burn in the 600°C heated steam; however, the Al powders do not ignite even at 900°C. The ignition delay time of AM powders was shorter than that of the Mg powders. The Al in the AM and Al powders does not react completely even when the temperature reached 900°C; however, the content of unreacted Al in the AM powders (13.9%) was much less than that in the Al powders (82.2%) at 900°C. The combustion process of the AM powders at 600°C is divided into three stages: the Mg in ...

Hydrogen production based in the corrosion of light metals in water solutions is an interesting alternative. Among all of them, Mg is probably the most adequate metal for energetic purposes due to its high electron density and oxidation potential. A safe and environmental-friendly method of hydrogen production from milled Mg–CoCl2 composites in water was proposed in this paper. An improved mechanism for the reactivity was developed. The experimental results indicated that the activated Mg–CoCl2 composites are very promising materials for hydrogen generation upon reaction with pure water. When immersed in pure water (50 °C), the hydrolysis reaction of the Mg-6 wt% CoCl2 composite began immediately, and the reaction rate reached 558.6 mL(min g)−1 in the first minute; the evolution of hydrogen reached 98.6% of the theoretical yield.

The epidemiologic characteristics of 631 infant pertussis cases12 months, which accounted for 57.42% of the total cases, were analyzed by descriptive epidemiology in Tianjin, between 2010 and 2015. The incidence of infants was 104.66/100,000, which was 118 times higher than in other age groups (P0.001). The primary type of pertussis simultaneously presented in households was adult-to-infant (70.51%). The parents were identified as the source of infection in 80.18% of cases for infants. The positive rate of placental antibody transfer was 31.06% and 3.13% for 3-month-old infants. Infants presented the highest age-specific pertussis incidence. The most important reason was parents were the important sources of infection, and secondly the lower level of antibodies in neonates and the rapid waning of maternal antibody titer.

The reaction performance of activated Mg/CoCl 2 has been studied relative to its storage time, temperature, RH (relative humidity), and storage methods. Activated Mg/CoCl 2 was prepared via high-energy milling and characterised using SEM (scanning electron microscopy) and TG (thermogravimetric analysis). The samples were aged for 30 days at different RH and temperatures. Three different methods were used to store the powders at 30 °C and 60% RH. The results showed that the efficiency decreased rapidly when the storage time increased, and the highest hydrogen generated rate decreased dramatically from 41.0 to 2.0 ml s −1 g −1 after 1 day, reaching 0.7 ml s −1 g −1 after 30 days at 60% RH and 20 °C. The efficiency of the sample decreased more in warmer and more humid atmospheres. The efficiency of the sample stored in the Ziploc bag remained almost unchanged during the first five days before decreasing from 81.9% to 66.5%. As expected, the efficiency only decreased 1.5% after 30 days in the Snap-Cap Centrifuge tube.

For the hard and brittle materials like optical glasses, ultra-precision grinding machine is primarily used, which can generate parts with high surface finish, high form accuracy and surface integrity. Motorized spindle is an inevitable choice of ultra-precision machine, but it has a prominent heat problem for its specific configuration of build-in motor. The paper does some research about motorized spindle thermal property. The heat resources and heat transferring ways are analyzed. The temperature distribution and deformation distribution of motorized spindle system are calculated through thermal structure coupling finite element analysis. The analysis results can provide warranty for motorized spindle design.

The reservoir optimal operation depends on not only specific characteristics of reservoirs and hydropower stations but also stochastic inflows. The key issue of actual hydropower operation is to make an approximate optimal decision triggered by limited inflow forecasts. To implement actual optimal operation of hydropower system with limited inflows forecast, this paper makes use of Support Vector Regression (SVR) to derive optimal operating rules. To improve the performance of SVR, parameters in SVR model are calibrated with grid search and cross validation techniques. The trained SVR model describes the complex nonlinear relationships between reservoir operation decisions and factors by considering both generalization and regression performance, which overcomes local optimization and over fitting deficits. Hybrid programming platform is further developed to implement system simulation. This SVR model along with simulation platform is applied to the largest hydropower base in China – Jinsha system. Three scenarios are developed for comparison: deterministic optimal operation, SVR based simulation with calibrated parameters, SVR based simulation with default parameters. Comprehensive evaluation indicates that, operating rules derived from SVR presents a reliable performance in system power generation and output processes with respect to ideal deterministic results, especially when the parameters are calibrated. Hybrid programming technique provides a feasible and compatible platform for future research.

Experiments were conducted to study the effect of magnesium–aluminum alloy on the combustion performance of hydroreactive fuel propellants. The raw metal powders added to the propellants were ball-milled magnesium–50% aluminum alloy (m-AM), magnesium–50% aluminum alloy (AM), and Al and magnesium (Mg) powders, which were characterized using scanning electron microscopy, X-ray diffraction (XRD), and simultaneous thermogravimetric analysis (TGA). A high-pressure combustor and a metal/steam reactor were used to simulate the two-stage combustion of hydroreactive propellants used for a water ramjet. The combustion performance of the metal powders in propellant was studied experimentally, and the efficiency of the Al reaction in the propellants during the two-stage combustion was calculated. TGA traces in air indicated that the oxidation onset temperature of AM powders is much lower than for both Mg and Al powders. The XRD patterns for the AM and m-AM alloys exhibited Al12Mg17 diffraction peaks. The hydroreactiv...

Activated Mg-based powders are prepared by high-energy milling and characterised with XRD, SEM, TG and BET techniques. This study focus on reactions of Mg-based powders with flowing steam that is heated at 500, 600, and 700 °C in a transparent pipe furnace. Morphologies and phases of solid reaction products are analysed by SEM, XRD, and residual metal content, and ignition delay times are measured. Experimental results show that all Mg-based powders oxidise at 500 °C and ignite at 600 °C. At 700 °C, all samples burn completely to form magnesium oxide (MgO) within 5 min. Residual metal contents and ignition delay times of all samples decrease with increasing temperature, and ignition delay times of activated Mg-based materials containing cobalto-cobaltic oxide (Co3O4) are only 22 s at 700 °C. Milled Mg powders are more reactive in heated steam than unmilled Mg powders, and the addition of Co3O4 further increases magnesium reactivity in heated steam.

Background: The effects of miR-92a on EPCs are still poorly elucidated. This study aimed to investigate the effects of miR-92a on EPCs (Endothelial progenitor cells) in a model of hypoxia (HO) or high glucose (HG)-induced EPCs injury by targeting GDF11 (Differentiation growth factor 11). Methods: The effects of miR-92a on EPCs subjected to HO or HG were investigated firstly. Subsequently, the action mechanism of miR-92a on EPCs by targeting GDF11 was elucidated. Proliferation, apoptosis, migration, angiogenesis was measured with MTT, flow cytometry, transwell, tube formation respectively. After 24 h, levels of reactive oxygen species (ROS) were measured by fluorescence intensity. LDH and NO (nitric oxide) levels were determined by ELISA. The expression of FLK-1 (fetal liver kinase 1) and vWF (von Willebrand factor) was detected by immunofluorescence. mRNA and protein expression levels were examined using PCR and western blotting respectively. The interaction between miR-92a and GDF11 was evaluated by dual-luciferase reporter assay. Results: Our results showed that HO or HG increased apoptosis, production of LDH and generation of ROS, but decreased the ability of migration and tube formation and generation of NO in EPCs; inhibiting of miR-92a decreased HO or HG-induced injury of EPCs, whereas miR-92a over-expression had the opposite effect; the protective effects induced by inhibiting of miR-92a on EPCs could be reversed by GDF11 siRNA and the harmful effects induced by over-expression of miR-92a could be rescued by over-expression of GDF11, which showed that the harmful effects of miR-92a be related to its inhibition of GDF11 and subsequent inactivation of the SMAD2/3/FAK/Akt/eNOS signaling pathway. Conclusions: Inhibiting miR-92a can protect EPCs from HO or HG-induced injury. The effect of miR-92a on EPCs are mediated by regulating of GDF11 and downstream SMAD2/3/FAK/Akt/eNOS signaling pathway.

Interruptible load contract is an important means of demand side management, but its existing models cant coordinate practicality with efficiency. Based on the curtailment cost function of consumers, this paper proposes an optional interruptible load contract and builds an optimal curtailment amount and compensation pricing model by introducing information display and incentive mechanism. The model can guide consumers voluntarily disclose the information on their true cost, and achieve the optimal allocation of load interruption. It is better to coordinate the relationship between utility and economic efficiency, which is more efficient than the traditional practical optional contract for interruptible load, and more practical than the theoretical model of interruptible load contract of fully nonlinear pricing. Numerical examples verify the effectiveness of the proposed model.

Large reservoir ecological risk assessment is an important part of ecological environmental protection and improvement. Taking Nuozhadu reservoir in Lancang river basin as an example, a multi-level risk receptor--multiple risk source evaluation index system which can describe the complicated relationship and mechanism of ecological risk is established in terms of recognizing ecological risk sources and receptors of the valley area of terrestrial ecosystems; Considering fuzziness of human cognition on ecological system, diversity and different measure standard of the risk evaluation indicators, the multi-level fuzzy comprehensive evaluation model based on RRM(Relative Risk Model) thought is constructed. Calculation results show that the ecological-risk fuzzy-evaluation score of each receptor and the overall score can be obtained, which can provide important reference for ecological environment improvement of Nuozhadu reservoir area through the comparative analysis.

A high-pressure combustor and a metal/steam reactor are used to simulate the two-stage combustion of hydro-reactive propellants used for a water ramjet. Raw metal powders added to the propellants are the aluminum power, magnesium powder, 50/50 aluminum-magnesium alloy (AM), and ball-milled 50/50 aluminum-magnesium alloy (b-AM), which are characterized by using scanning electron microscopy (SEM), x-ray diffraction (XRD), and simultaneous thermogravimetric analysis (TGA). The efficiencies of the Al reaction in the raw metal in heated steam and in the propellants during the two-stage combustion are calculated. The results indicate that both Mg and Al in the alloys, whether b-AM or AM, can react completely in air when heated up to 950°C. The XRD patterns for the combustion products of the AM and b-AM alloys in heated steam contain magnesium oxide MgO, spinel Al2MgO4, and Al diffraction peaks. The Al reaction efficiencies of the AM and b-AM alloy powders in heated steam are much higher than that of the Al powders. The hydroxyl-terminated polybutadiene (HTPB)-ammonium perchlorate (AP)-(b-AM)-Mg and HTPB-AP-AM-Mg propellant systems exhibit good performance in terms of the Al reaction efficiency, which are better than that of the HTPB-AP-Al-Mg and HTPB-AP-Al systems.

Willow is an abundant plant in many countries all over the world. It has an extremely rapid growing rate, and it can be considered as a sustainable raw material wood resource. In this study, H3PO4of catalyzed willow pyrolysis was investigated by means of CP-GC-MS. Moreover pyrolysis products such as furfural, levoglucosenone,levoglucosan and phenolic compounds was ananlyzed. The results indicate that H3PO4shows increased selectivity towards sugar and furan compounds at the expense of acetic acid and phenolic compounds. The biomass treatment with H3PO4enhances dehydration and decarbonylation of levoglucosan resulting in more furfural and levoglucosenone, promoting the lignin to form carbon rather than phenolic compounds. and inhibit acetic acid formation.. The content of the major sugar compounds reached 50% in the prensence of catalyst. The content of the major furan compounds enhanced, mainly furfural.

Based on the analysis of water supply and water demand in Tianjin city, the early-warning index system of water resources was determined. Then, applying the relative principle of catastrophe theory, all kinds of the slope change-points of early-warning index curves, including the differences of water supply and water demand, water supply, water demand, increasing curve of population in Tianjin, total industrial output value and increasing curve of GDP are obtained by the rate analysis for slope change-point. So, the slope change-points model is established for early-warning system of water resources security in Tianjin City. After applying the theory of set pair analysis, which set a pair of “water-rich state (flood disaster)” and “water-shortage state (drought disaster)”, early-warning threshold and degree of water resources security are uniformly presented by the index of difference of water supply and demand. In this way, we could illustrate the early-warning degrees. Finally, according to the ...

Objective We aimed to investigate the diagnostic value of apparent diffusion coefficient (ADC) maps in magnetic resonance imaging (MRI) in the volume of acute cerebral infarction (ACI). Methods A total of 207 ACI patients were selected in our study. The cerebral infarction (CI) volume in the initial diffusion-weighted imaging examination, minimum ADC value, relative apparent diffusion coefficient (rADC) value, and mean ADC value were measured. The correlations between age, smoking, drinking, hypertension, diabetes, coronary heart disease, clinical stage, the lowest ADC value, the mean ADC value, and the mean rADC value with CI volume were analyzed by logistic regression analysis. A receiver operating characteristic (ROC) curve was used to analyze the diagnostic value of the ADC value in the ACI volume. Results There was a significant difference in the distribution of the CI volume in ACI patients ( P .05). A significant difference was found in the signal intensity and percentage distribution of ADC map in patients of different CI groups with different CI volumes ( P .05). The signal of the ADC map was positively correlated with the CI volume. The mean ADC and rADC values had significant differences between different CI volumes (all P .05). Logistic regression analysis revealed that the mean ADC value was significantly correlated with the CI volume ( P .05). Analysis of the ROC curve showed that the quantitative value of ADC has a diagnostic value for the ACI volume. Conclusion This study has shown that the signal intensity change on the ADC map in MRI and quantitative analysis of the ADC value can be used as a reference for predicting the ACI volume.

Objectives: The KAI1/CD82 appears to inhibit multiple steps of cancer metastatic. D2-40 labeled LVI and LVD are also closely associated with cancer metastasis. We investigated the expression levels of KAI1/CD82, D2-40 labeled LVI and LVD and their correlation with clinicopathological factors in ESCC. Methods: Immunohistochemistry and Western Blot were used to detect KAI1/CD82 expression levels in the peritumoral tissue and ESCC. LVI and LVD detected by D2-40 immunohistochemical staining. The relationships between the KAI1/CD82 expression levels, LVI and LVD were analyzed. The prognosis of ESCC was analyzed by Kaplan-Meier survival analysis and Cox’s proportional hazards model. Results: KAI1/CD82 expression was markedly lower in ESCC than in the para-carcinoma tissue (P

Hydro-reactive Mg–Al mechanical alloy materials are prepared by high-energy milling. Scanning electron microscopy (SEM), thermogravimetric (TG) and powder X-ray diffraction (XRD) techniques are used to characterize the materials. Their hydrolysis properties are studied in seawater by measuring the hydrogen volume produced and by calculating the rate of hydrogen evolution. The collected reaction products are analyzed after hydrolysis. The experimental results show that there are the squashed, overlapped and fined steps for metal powder in the milling progress. As the milling time increases from 0 to 4 h, the initial oxidization temperature of Mg–Al mechanical alloy materials first increases, and then decreases. An increase in milling time is found to improve the hydrogen generation rate and the hydrogen yield during hydrolysis. When the milling time reaches 4 h, the hydrolysis reaction is immediately noticeable, generating 397 mL(min g) −1 of hydrogen within the first second minutes, and the total hydrogen evolution is 950 mL of hydrogen, or 97.1% of the theoretical yield.

A high-pressure combustor and a metal/steam reactor were used to simulate the two-stage combustion of a fuel-rich propellant used for water ramjet engines. The solid combustion products from the two stages were collected and characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). In addition, the thermal properties of the solid products of the primary combustion were characterized by differential thermal analysis (DTA) and simultaneous thermogravimetry (TG). The burning rates at different pressures were measured and the secondary combustion process in hot steam was monitored by high-speed cinematography. The results showed that the propellant has a good combustion performance and a high burning rate. After primary combustion, the solid product mainly contained magnesium, magnesia, magnesium chloride, and carbon. During the secondary combustion, the ignition temperature was approximately 720 °C, and two burning stages were observed. The rest of magnesium hasn’t completely reacted with hot steam until the temperature reached a value higher than 800 °C for 30 min.

A high power orthogonally polarized mid-infrared (mid-IR) laser was realized by a singly resonant optical parametric oscillator (SROPO) employing two KTA crystals with the Z-axes perpendicular to each other. The SROPO was pumped by a diode-end-pumped acoustic-optically (AO) Q-switched Nd:YAG laser, and each of the KTA crystals used a differently polarized part of the fundamental wave and participated in separated frequency conversion. The maximum SROPO output power of 2.18 W including 0.98 W of signal at 1535 nm and 1.2 W of idler at 3468 nm was obtained at a repetition rate of 6 kHz and an absorbed pump power of 16.5 W, corresponding to an optical-to-optical conversion efficiency of up to 13.2 % and a slope efficiency of 19.4 %. The 3468-nm beam M2-factor of 1.6 was measured by a beam analyzer.

Two graphene oxide saturable absorbers (GO-SAs) spin coated on indium tin oxide (ITO) substrate have been prepared and their transmissivity spectra have also been measured. The performance of the diode-pumped passively Q-switched Nd:YVO4 laser with GO-SA has been investigated for the first time. The shortest pulse width of 113 ns and the highest peak power of 4.3 W are obtained at the pump power of 5.04 W. The output laser characteristics have demonstrated that graphene oxide is a promising saturable absorber for passive Q-switching.

Mg-based lamellar materials were prepared by high-energy milling. The XRD, SEM, TG and BET techniques were used to characterize the materials. Their hydrolysis properties in seawater were studied by measuring the hydrogen volume produced and by calculating the rate of hydrogen evolution. The solid hydrolysis products were analyzed by SEM and XRD. The experimental results showed that the milled samples were substantially more reactive than the unmilled Mg powder in air according to initial oxidization temperature. In the hydrolysis process, the unmilled Mg powder barely reacted with seawater. However, the milled Mg powder showed noticeable reactivity in seawater, generating 906 mL/g of hydrogen in 10 min, an evolution of 97.1% of the theoretical yield. The Mg-based hydro-reactive materials including Co or Ni were more reactive in seawater than milled Mg powder due to the creation of a micro-galvanic cell. The Mg/Co sample produced 575 mL/g of hydrogen in the first minute. Mg(OH) 2 was the main reaction product of magnesium with seawater. It accumulated in a three-dimensional form composed of nanosized Mg(OH) 2 chip.

Continuous-wave (CW) and passively Q-switched operations of laser diode-end-pumped Nd:CLTGG laser at 1.06 μm was demonstrated for the first time. The laser spectrum was found to be tri-wavelength, with respective wavelengths of 1058.4, 1060.5, and 1065.5 nm for both CW and passive Q-switching regime. The highest CW output power of 2.6 W was obtained with an optical-optical conversion efficiency of 13.9% and a slope efficiency of 17.1%. In the passive Q-switching regime, the highest output power, shortest pulse width, largest pulse energy and highest peak power were achieved as 242 mW, 45.8 ns, 1.65 μJ and 0.4 kW, respectively. The passively Q-switched tri-wavelength laser should have the potential to be used for terahertz radiation generation.

Removal rates of Pb, Hg and As ions in lotus leaf extracts obtained by Micelles- complexation-supercritical CO2 extraction through an orthogonal experiment(L16(45)) were investigated to get the best extraction conditions. The results of orthogonal experiments indicated that the removal rate of Pb, Hg and As ions trace heavy metal ions is high by complexaction and reverse micelles in supercritical carbon dioxide (Sc-CO2), and the removal rate of Pb, Hg, As from lotus leaf is 87.85%, 89.19% and 84.72% respectively with the loss rate of total flavonoids is 8.73% under the potential optimum conditions which are 50°C, 20 MPa, 1.5 h, the concentration of Triton X-100 of 0.15 mol.L-1, the mass of complexing agent is 0.1 g.

The solubility of 8-hydroxyquinoline lead, lead diethyldithiocarbamate, 8-hydroxyquinoline mercury and mercury diethyldithiocarbamate in supercritical carbon dioxide under different supercritical conditions was investigated by using supercritical extraction device. It was measured ranged from 308.15K to 328.15K for supercritical temperature, and 10 MPa to 30MPa for pressure. The solubility data of metal complexes were correlated and a mathematical model was put forward from a viewpoint of solvent association theory compared to Chrastil’s model. The results showed that SA model gives fairly good agreement with the experiment data.

In this article, a diode-end-pumped passively Q-switched extra-cavity frequency doubled micro-type green laser by Nd:YAG/Cr4+:YAG composite crystal was demonstrated. The dependence of the average out power, pulse width and pulse repetition rate on incident pump power were measured. Under the pump power of 14 W, the minimum pulse width of 1.3 ns with repetition rate of 68.0 kHz was obtained, corresponding single-pulse energy of 8.8 μJ and peak power of 6.7 kW.

A novel nonlinear frequency conversion process was demonstrated to realize the synchronized dual-wavelength emissions at 1534 and 1572 nm by the mixed optical parametric oscillation (OPO) conversion in gray-tracking-resistance KTP (GTR-KTP) and KTA crystals. Both the two crystals were inserted into the diode-pumped Nd:YAG/Cr4+:YAG fundamental resonator, with their Y axes perpendicular to each other. This could eliminate the competition of the two OPO processes in fundamental radiation. Furthermore, the ratio between the length of GTR-KTP and KTA has also been specially designed to satisfy the same OPO thresholds. The synchronized dual-wavelength lasing with the power ratio of 1:1 between 1534 and 1572 nm was successfully realized. At an incident LD pump power of 7 W, the maximum total output power of 460 mW was achieved, with the corresponding pulse width and repetition rate measured to be 3.9 ns and 5.5 kHz, respectively. This mixed conversion opens a new door for the multi-wavelength lasing.

Diode end-pumped continuous-wave and passively Q-switched Nd:Lu x(x = 0.5) Y 1 − x VO 4 mixed crystal lasers were demonstrated. At the pump power of 12.6 W, the maximum output power of 6.7 W around 1066.5 nm was obtained with the output transmission of 27%. The optical conversion efficiency is 53.2%, corresponding to a slope efficiency of 55.8%. For pulsed operation, the shortest pulse width attained was 8.6 ns, with the pulse repetition frequency of 99 kHz, and the single pulse energy and the peak power were estimated to be 25.5 μJ and 2.96 kW, respectively.

Diode end-pumped continuous wave (CW) and passively Q-switched (PQS) laser performances of the mixed Nd:Gd0.33Lu0.33Y0.33VO4 crystal are investigated for the first time. At the pump power of 9 W, the highest output power is 3.66 W, with an optical conversion efficiency of 40.7% and a slope efficiency of 43.6%. For pulsed operation, the minimum pulse width of 9.2 ns with Cr4+:YAG as saturable absorber is attained with the repetition rate of 81.8 kHz, and the single pulse energy and peak power are estimated to be 9.78 J and 1.06 kW, respectively.

This paper reported a broadband tuning intracavity optical parametric oscillator (IOPO), based on the multiple grating periodical poled lithium niobate (PPLN) pumped by a acoustic-optical (AO) Q-switched Nd:YVO4 laser. The widely tunable OPO output signal wavelength range from 1390 to 1605 nm, which was obtained by changing PPLN poling period from 27.8 to 31.6 μm at a certain temperature of 46°C, while the continuous tuning range was measured from 1475 to 1592 nm with the PPLN poling period of 30 μm by varying the temperature of nonlinear crystal PPLN from 50 to 120°C. The maximum output power of 0.92 W at 1534 nm with the minimum pulse width of 5.17 ns was generated under the incident pump power of 9.6 W at 808 nm. The corresponding peak power and single pulse energy were calculated to be 5.94 kW and 30.7 μJ, respectively. The M2-factor was measured to be 2.01 at the signal power of 0.4 W.

The simultaneous stimulated Raman scattering (SRS) and optical parametric oscillation (OPO) for the 1064 nm radiation were realized in one KTP crystal for the first time. At an incident diode laser power of 8.6 W, the maximum average output powers at 1096 nm and 1572 nm were 1.1 W and 0.36 W, respectively. The conversion efficiency to Stokes with respect to the incident diode power was as high as 12.8%. The corresponding minimum pulse widths at 1096 nm and 1572 nm were 2.8 and 1.1 ns, respectively.

The efficient dual-wavelength oscillation at 1064 and 1342 nm in the passively Q-switched laser based on Nd:YVO4/V3+:YAG is successfully obtained, as demonstrated in this paper. A total average output power of 2.2 W is obtained with 1.3 W for 1064 nm and 0.9 W for 1342 nm under the incident pump power of 7.7 W, corresponding to a total optical-optical conversion efficiency of 28.2%. The pulse widths are 58 and 54 ns for 1064 and 1342 nm, respectively, with the repetition rate of 89 kHz. Moreover, a rate equation model considering the Gaussian spatial distributions of the intracavity photon density and the initial population-inversion density is presented to characterize the dual-wavelength passive Q-switching operation.

We report a passively mode-locked Yb:Y2Ca3(BO3)4 (Yb:CYB) laser with a partially reflective semiconductor saturable-absorber mirror. The minimum pulse duration of 244-fs with a repetition rate of ~ 55 MHz has been obtained at the central wavelength of 1044.7 nm (8.1 nm full width at half maximum (FWHM)). The measured average output power amounts to 261 mW under the absorbed pump power of 7.0 W. To our best knowledge, this is the first demonstration of a femtosecond Yb:CYB laser.

A simultaneous dual-wavelength eye-safe laser at around 1.9 and 1.7 μm based on only a single KTiOAsO4 (KTA) intracavity optical parametric oscillator (IOPO) is firstly reported. The dual-wavelength-IOPO is driven by an acousto-optic (AO) Q-switched Nd:YAG laser, which is simultaneously oscillated at the radiations of 1.3 and 1.06 μm. Within the KTA-IOPO cavity, the signal output waves of IOPO at the wavelength of 1.9 and 1.7 μm are pumped by the 1.3 and 1.06 μm radiations from Nd:YAG laser, respectively. With the laser diode pumped power of 100 W and the pulse repetition rate of 4 kHz, the maximum average output power of 1.3 W at 1895 nm with the pulse duration of 30 ns and that of 0.9 W at 1715 nm with the pulse duration of 18 ns are obtained. With different diode pump power, the central wavelength of IOPO signal light at 1.9 μm is tunable from 1850 to 1895 nm, while the other signal wave at 1.7 μm is from 1650 to 1715 nm.