A novel launch dynamics measurement system for multiple launch rocket system and comparative analysis with numerical simulations

In this paper,a novel launch dynamics measurement system based on the photoelectric sensor pair is built.The actual muzzle time(i.e.a time duration that originates from the initial movement to the rocket’s departure from the muzzle)and the muzzle velocity are measured.Compared with the classical methods,the actual muzzle time is obtained by eliminating the ignition delay.The comparative analysis method is proposed with numerical simulations established by the transfer matrix method for multibody systems.The experiment results indicate that the proposed measurement system can effectively measure the actual muzzle time and reduce the error of classical methods,which match well with the simulation results showing the launch dynamics model is reliable and helpful for further analysis and design of the MLRS.

Screening,identification and antagonistic effect of antagonistic bacteria JTFM1001 against aflatoxin contamination in corn

Aflatoxin is a strong carcinogenic and toxic fungal toxin produced by Aspergillus flavus and other Aspergillus species,and can seriously threaten the health of consumers,thus becoming a global concern.Corn,as an important oil and economic crop,is highly susceptible contaminated by aflatoxin.In this study,antagonistic bacteria with strong inhibitory effect on aflatoxin were screened to provide support for the treatment aflatoxin contamination control in corn.Ten strains which have strong antagonistic effects against A.flavus were isolated from healthy corn from different corn producing areas in China.Among them,the antagonistic bacteria JTFM1001 through corn kernels in vivo and field experiment,the inhibition effect of aflatoxin contamination reached above 70%and 55%,respectively.And the strain was identified as Bacillus subtilis based on its morphological,physiological and biochemical characteristics and phylogenetic analysis of 16S rDNA.In addition,our data showed that it can colonize in the rhizosphere and survive for a long time,forming the dominant flora,with broad application prospect.Finally,we were surprised to find that the antibacterial metabolites secreted by the antagonistic bacteria was one of the mechanisms of its inhibition of A.flavus and aflatoxin.This will provide us with new ideas and perspectives on the effective prevention and control of aflatoxin contamination in corn and corn oil.

Review on contaminants in edible oil and analytical technologies

Edible oil is an important part of the human daily diet,which is popular in the food industry.People are paying increasing attention to the safety of edible oil as flawed oils have caused enormous international losses and posed a huge threat to consumer health issues.Therefore,it is necessary and important to analyze the quality and safety of oil product.In the present study,we particularly reviewed recent literature on analysis of emerging pollutants in edible oil including mycotoxins,pesticide residues and heavy metals.In addition,a series of emerging analytical technologies(HPLC,LC-MS/MS and GC-MS)for these contaminants were also summarized in this paper.

Effects of rosuvastatin on expression of angiotensin-converting enzyme 2 after vascular balloon injury in rats

Objective To investigate the effects and mechanisms of rosuvastatin on angiotensin -converting enzyme 2 (ACE2) in the process of neointimal formation after vascular balloon injury in rats, and to explore the effects of ACE2 and rosuvastatin in restenosis. Methods Thirty-six Wistar rats were randomly allocated into three groups: control group (n = 12), surgery group (n = 12), and statin group (n = 12). Aortic endothelial denudation of rats was performed using 2F balloon catheters. At days 14 and 28 after injury, aortic arteries were harvested to examine the following. Intimal thickening was examined by hematoxylin and eosin staining. We measured angiotensin II (Ang II) and angiotensin 1-7 (Ang-[1–7]) levels by a radioimmunological method or enzyme-linked immunosorbent assay. Protein andmRNAexpression of ACE2 and Ang II type 1 receptor (AT1) were investigated by immunohistochemistry, Western blots, and Reverse transcriptase- polymerase chain reaction (RT-PCR). We measured changes in proliferating cell nuclear antigen (PCNA) by immunohistochemistry. The level of phosphorylated extracellular signal regulated kinase 1/2 (P-ERK1/2) was evaluated byWestern blotting. Results Proliferation of vascular smooth muscle cells (VSMC) and intimal thickening were higher at day 14 after vascular balloon injury in the surgery group compared with the control group. Proliferation of VSMC was decreased by day 28 after injury, while intimal thickening continued. With rosuvastatin treatment, the extent of VSMC proliferation and intimal thickening was reduced at day 14 and 28 after injury. Ang II and P-ERK levels were significantly increased, Ang-(1–7) levels were significantly decreased, mRNA and protein expressions of ACE2 were significantly decreased, and AT1 expression was significantly increased at days 14 and 28 after vascular balloon injury in the surgery group compared with the control group. PCNAexpression was higher in the surgery group than in the control group, and it was significantly decreased after being given rosuvastatin. Expression of ACE2 mRNA and protein, and Ang-(1–7) levels were significantly increased, while AT1 expression and levels of Ang II and P-ERK were significantly decreased in the statin group compared with the surgery group. Conclusions Expression of ACE2 mRNA and protein is decreased in the process of intimal thickening after balloon injury. The inhibitory effect of rosuvastatin on intimal thickening is related to upregulation of ACE2, an increase in Ang-(1–7), downregulation of AT1, and activation of the P-ERK pathway.

Left bundle branch pacing in a ventricular pacing dependent patient with heart failure:A case report

BACKGROUND Left bundle branch pacing(LBBP)is a physiological pacing method that has emerged in recent years.It is an ideal choice for patients with complete left bundle branch block who are in need of cardiac resynchronization therapy(CRT).Moreover,LBBP is superior in maintaining physiological ventricular activation and can effectively improve heart function and quality of life in patients with pacemaker-induced cardiomyopathy.However,LBBP in pacing-dependent patients who already have cardiac dysfunction has not been well assessed.CASE SUMMARY A 69-year-old male patient presented with symptoms of chest tightness,palpitation and systolic heart failure with New York Heart Association class III for 1 mo.The 12-lead electrocardiogram showed atrial fibrillation with third-degree atrioventricular block and ventricular premature beat.Holter revealed a right bundle branch block,atrial fibrillation with third-degree atrioventricular block,frequent multifocal ventricular premature beats,Ron-T and ventricular tachycardia.The echocardiogram documented an enlarged left atrium and left ventricle and a low left ventricular ejection fraction.Coronary angiography indicated a stenosis of 30%in the middle left anterior descending artery.Apparently,a CRT-D pacemaker was the best choice for this patient according to previous findings.However,the patient was worried about the financial burden.A single-chamber pacemaker with LBBP was selected,with the plan to take amiodarone and upgrade with dual-chamber implantable cardioverter-defibrillator or CRT-D at an appropriate time.During the follow-up at 3 mo after LBBP,the patient showed an improvement in cardiac function with slight improvement in echocardiography parameters,and the New York Heart Association functional class was maintained at I.Moreover,the patient no longer suffered from chest tightness and palpitation.Holter showed decreased ventricular arrhythmia of less than 5%.CONCLUSION LBBP might be used in patients with heart failure and a high-degree atrioventricular block as an alternative to conventional CRT.

Evolution of Energy in Submerged Granular Column Collapse

The evolution of energy in subaerial and subaqueous granular column collapses is studied.Employing the refractive index matching method and planar laser-induced fluorescence technique,we obtain granular and liquid images simultaneously in a single experiment of subaqueous flow.Particle image velocimetry and particle tracking velocimetry are used to process the data for the fluid and granular phase.We find stepwise decreases in the total kinetic energy of the granular material.The stage of rapidly falling energy corresponds to large transverse changes in the direction of the massive granular particles.Moreover,in this stage,a major fraction of the granular kinetic energy transferred from the granular potential energy is lost or transferred.Interestingly,compared with dry granular flow,the existence of an ambient liquid seems to reduce the total dissipated energy,which may be the reason why previous studies observed similar granular runout distances in subaqueous and dry granular collapses.

Is heart rate reduction more important than target dose in chronic heart failure therapy with a beta-blocker?

1 Introduction Beta-adrenoceptor blocking agents(beta-blockers)are now well established as cornerstone therapy in patients with systolic chronic heart failure(CHF).[1]Clinical data have overwhelmingly proven the beneficial effects of beta-blocker therapy in terms of improving patient prognosis,decreasing requirements for hospitalization,and postponing disease progression.[2-4]However,it remains unclear what the optimal efficacious and safe dose for an individual patient with CHF is,and whether this can simply be inferred from the target dose for each beta-blocking agent as used in the major clinical trials.

Clinical Characteristics and Outcomes of Severe or Critical COVID-19 Patients Presenting No Respiratory Symptoms or Fever at Onset

It is difficult to identify suspected cases of atypical patients with coronavirus disease 2019(COVID-19),and data on severe or critical patients are scanty.This retrospective study presents the clinical,laboratory,and radiological profiles,treatments,and outcomes of atypical COVID-19 patients without respiratory symptoms or fever at onset.The study examined ten atypical patients out of 909 severe or critical patients diagnosed with COVID-19 in Wuhan Union Hospital West Campus between 25 January 2020 and 10 February 2020.Data were obtained from the electronic medical records of severe or critical patients without respiratory symptoms or fever at onset.Outcomes were followed up to discharge or death.Among 943 COVID-19 patients,909(96.4%)were severe or critical type.Of the severe or critical patients,ten(1.1%)presented without respiratory symptoms or fever at admission.The median age of the ten participants was 63 years(interquartile range(IQR):57–72),and seven participants were men.The median time from symptom onset to admission was 14 d(IQR:7–20).Eight of the ten patients had chronic diseases.The patients had fatigue(n=5),headache or dizziness(n=4),diarrhea(n=5),anorexia(n=3),nausea or vomiting(n=3),and eye discomfort(n=1).Four patients were found to have lymphopenia.Imaging examination revealed that nine patients had bilateral pneumonia and one had unilateral pneumonia.Eventually,two patients died and eight were discharged.In the discharged patients,the median time from admission to discharge lasted 24 d(IQR:13–43).In summary,some severe or critical COVID-19 patients were found to have no respiratory symptoms or fever at onset.All such atypical cases should be identified and quarantined as early as possible,since they tend to have a prolonged hospital stay or fatal outcomes.Chest computed tomography(CT)scan and nucleic acid detection should be performed immediately on close contacts of COVID-19 patients to screen out those with atypical infections,even if the contacts present without respiratory symptoms or fever at onset.

Preparation of Nanoiron by Water-in-Oil (W/O) Microemulsion for Reduction of Nitrate in Groundwater

Nanometer-sized iron particles with monodispersity and narrow size distribution were synthesized by modi-fied microemulsion system using environment-friendly non-ionic surfactants Span 80 and Tween 60 as mixed surfactants. The synthesized iron nanoparticles were characterized by using powder X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results show that the synthesized particles were mainly composed of α-Fe with an average diameter of 80-90 nm. The chemical activity of the obtained iron nanoparticles was evaluated by the denitrification of nitrate in water. On neutral condition, complete denitri-fication of nitrate was achieved by freshly synthesized nanoiron within 30 min. Ammonia was the main product, with good material balance at the end of the reaction. Two possible reaction pathways for nitrate reduction by nanoiron have been proposed in this study.

Demonstration and Promotion of Integrated Management Technology of Wheat Sheath Blight and Wheat Crown Rot in Zibo City

Since 2014, Zibo Plant Protection Station has carried out a series of prevention and control tests in the city to solve the problem of increasingly aggravated root and stem diseases of wheat. According to the results of individual test, the technical procedures for integrated management of wheat sheath blight and wheat crown rot based on deep tillage, seed coating and chemical control in spring are integrated. The technique has been greatly promoted through on-site meetings, training and publicity, demonstration and promotion, unified prevention and control, and green prevention and control, which increases wheat yield in technology application area, reduces the use of chemical pesticides, and protects the ecological environment. The radiation drives increasing production and incomes of the surrounding farmers, receiving remarkable economic, social and ecological benefits.

Implantable defibrillator lead extraction with optimized standard extraction techniques

Background Implantable cardioverter-defibrillator (ICD) leads might not be extracted especially in developing countries because of the high cost and lack of specialized tools. We aimed to evaluate transvenous extraction of ICD leads using optimized standard techniques. Methods We prospectively analyzed clinical characteristics, optimized extraction techniques and the feasibility of extraction for 40 patients (33 males; mean age 47.9 ±16.1 years) with 42 ICD leads. Results Complete procedural success rate was 95.2% (40/42), and the clinical success rate was 97.6% (41/42). One ICD lead required cardiothoracic surgery. Minor complications occurred in three cases (7.5%), and no major complications or death occurred. Locking stylets were used to extract most leads (34, 81.0%) and almost half of the leads (20, 47.6%) required mechanical dilatation to free fibrotic adhesions; these leads had been implanted for a longer period of time than the others (43.7 ± 18.2 vs. 18.4 ±13.4 months, P < 0.05). Three-quarters of the leads (30, 71.4%) were extracted with locking stylets plusmanual traction (12, 28.6%), or mechanical dilatation with counter-traction (18, 42.8%) by the superior vena cava approach and one-quarter of the leads (11, 26.2%) were removed by optimized snare techniques using the femoral vein approach. Median extraction time was 20 min (range 2–68 min) per lead. Linear regression analysis showed that the extraction time was significantly correlated with implant duration (r = 0.70, P < 0.001). Median follow-up was 14.5months (range 1–58 months), no infection, or procedure-related death occurred in our series. Conclusions Our optimized procedure for transvenous extraction of ICD leads provides a practical and low-costmethod for standard procedures.

高密度电法在不稳定斜坡勘察治理中的应用

为查明湖南杨村一带因碎石、土体常年废弃堆积形成的不稳定斜坡的规模大小,采用高密度电法对其厚度和滑动界面进行了探测。根据土体和下伏基岩电阻率差异特征,对测量成果进行了推断解释;同时,以60Ω·m为异常上限,圈化了内部滑动界面。通过钻探验证,在20/L2测点揭露土体厚度为27.2m,物探推断厚度为24.0m,准确度达88.2%;在32/L3测点处揭露0~4.5m为含水土体和强风化碎石,与物探成果显示的浅表层状低阻十分吻合。由此说明,在探测目标层与基岩电性差异明显的情况下,通过高密度电阻率法测量可有效查明控滑控崩界面,可为地质灾害危险性评估和后期治理提供参考依据。

Functional Fibers and Functional Fiber‑Based Components for High‑Power Lasers

The success of high-power fiber lasers is fueled by maturation of active and passive fibers,combined with the availability of high-power fiber-based components.In this contribution,we first overview the enormous potential of rare-earth doped fibers in spectral coverage and recent developments of key fiber-based components employed in high-power laser systems.Subsequently,the emerging functional active and passive fibers in recent years,which exhibit tremendous advantages in balancing or mitigating parasitic nonlinearities hindering high-power transmission,are outlined from the perspectives of geo-metric and material engineering.Finally,novel functional applications of conventional fiber-based components for nonlinear suppression or spatial mode selection,and correspondingly,the high-power progress of function fiber-based components in power handling are introduced,which suggest more flexible controllability on high-power laser operations.

Effect of viscosity on motion of splashing crown in high speed drop impact

A splashing crown is commonly observed when a high-speed drop impacts a liquid film. The influence of the liquid viscosity on the crown＇s evolution is not yet clear. We review several existing theories of this problem, and carry out a series of numerical simulations. We find that a three-segment model can describe the crown＇s motion. In the very early stage when the crown is barely visible, the influence of viscosity is small. Later, a shallow water approach used in most existing models is applicable as long as the initial conditions are formulated properly. They depend on viscous dissipation in the intermediate period. Preliminary estimation based on a dissipation function is proposed to characterize the influence of viscosity in this problem.

Hundred-watt level high-order mode all-fiberized random distributed feedback Raman fiber laser with high mode purity

An all-fiberized random distributed feedback Raman fiber laser(RRFL)with LP_(11) mode output at 1134 nm has been demonstrated experimentally,where an intracavity acoustically induced fiber grating is employed for modal switching.The maximum output power of LP_(11) mode is 93.8 W with the modal purity of 82%,calculated by numerical mode decomposition technology based on stochastic parallel-gradient descent algorithm.To our best knowledge,this is the highest output power with high purity of LP_(11) mode generated from the RRFL.This work may pave a path towards advanced fiber lasers with special temporal and spatial characteristics for applications.

基于折射率匹配实验图像指标的含液颗粒物质系统内部固体体积分数重构

折射率匹配技术被广泛用于研究颗粒-液体混合流动,但是目前针对其固体体积分数的确定为经验性的且缺乏理论或实验支撑.为了合理确定内部体积分数,本文开展了系统的标定实验来研究固体体积分数和图像指标的关系.结果表明基于面积分数的模型由于颗粒表观尺寸的不稳定性,会产生较大的误差,传统使用的正比例模型仅在靠近标定点附近的体积分数成立.本文提出了基于Voronoi多边形等效直径的预测模型,结果表明该模型更为准确且稳定,该模型被进一步应用于颗粒-液体斜槽流动中以研究内部体积分数剖面和底部应力.

Association of platelet to lymphocyte ratio with in-hospital major adverse cardiovascular events and the severity of coronary artery disease assessed by the Gensini score in patients with acute myocardial infarction

Background:The platelet to lymphocyte ratio(PLR)has recently emerged as a potential inflammatory biomarker and has been shown to be significantly associated with atherosclerotic coronary artery disease(CAD).Therefore,we aimed to explore the association of PLR with in-hospital major adverse cardiovascular events(MACEs)and the severity of CAD assessed by the Gensini score(GS)in patients with acute myocardial infarction(AMI)undergoing coronary angiography.Methods:A total of 502 patients with AMI consecutively treated at the Affiliated Hospital of Qingdao University(Qingdao,China)and underwent coronary angiography from August 2017 to December 2018 were recruited in this study.The demographic,clinical,angiographic characteristics,and laboratory parameters were collected.According to the presence of in-hospital MACEs,the included patients were divided into the MACE group(n=81)and the non-MACE group(n=421).Further,according to tertiles of the GS,the patients were classified into three groups:the low GS group(GS≤32 points,n=173),medium GS group(32 points<GS≤60 points,n=169),and high GS group(60 points<GS≤180 points,n=160).The main statistical methods included Chisquared test,non-parametric Mann-Whitney U test,Kruskal-Wallis H test,logistic regression,and receiver operating characteristic curves.Results:The PLR in the MACE group was significantly higher than that in the non-MACE group(179.43[132.84,239.74]vs.116.11[87.98,145.45],Z=-8.109,P<0.001).Further,there were significant differences in PLR among the tertiles of GS(110.05[84.57,139.06]vs.119.78[98.44,157.98]vs.140.00[102.27,191.83],H=19.524,P<0.001).PLR was demonstrated to be an independent risk factor of in-hospital MACEs(odds ratio[OR]:1.012,95%confidential interval[CI]:1.006-1.018,P<0.001)and severe CAD assessed by the GS(OR:1.004,95%CI:1.002-1.009,P=0.042).The cutoff value of PLR for predicting the development of in-hospital MACEs was 151.28 with a sensitivity of 66.7%and a specificity of 78.1%(area under the curve[AUC]:0.786,95%CI:0.730-0.842,P<0.001),and a PLR of 139.31 was also identified to be an effective cutoff point for detecting a high GS(<60 points)with a sensitivity of 49.4%and a specificity of 69.6%(AUC:0.611,95%CI:0.556-0.666,P<0.001).Conclusions:PLR as a novel inflammatory marker is significantly and independently associated with the occurrence of in-hospital MACEs and the severity of CAD assessed by the GS in patients with AMI.As an easily available and inexpensive inflammatory indicator,PLR could be widely used as an efficient inflammatory biomarker for identifying high-risk patients and for individualizing targeted therapy to improve the prognosis of AMI.

Lactate metabolism in human health and disease

The current understanding of lactate extends from its origins as a byproduct of glycolysis to its role in tumor metabolism,as identified by studies on the Warburg effect.The lactate shuttle hypothesis suggests that lactate plays an important role as a bridging signaling molecule that coordinates signaling among different cells,organs and tissues.Lactylation is a posttranslational modification initially reported by Professor Yingming Zhao’s research group in 2019.Subsequent studies confirmed that lactylation is a vital component of lactate function and is involved in tumor proliferation,neural excitation,inflammation and other biological processes.An indispensable substance for various physiological cellular functions,lactate plays a regulatory role in different aspects of energy metabolism and signal transduction.Therefore,a comprehensive review and summary of lactate is presented to clarify the role of lactate in disease and to provide a reference and direction for future research.This review offers a systematic overview of lactate homeostasis and its roles in physiological and pathological processes,as well as a comprehensive overview of the effects of lactylation in various diseases,particularly inflammation and cancer.

Deep-learning-assisted, two-stage phase control method for high-power mode-programmable orbital angular momentum beam generation

High-power mode-programmable orbital angular momentum(OAM)beams have received substantial attention in recent years.They are widely used in optical communication,nonlinear frequency conversion,and laser processing.To overcome the power limitation of a single beam,coherent beam combining(CBC)of laser arrays is used.However,in specific CBC systems used to generate structured light with a complex wavefront,eliminating phase noise and realizing flexible phase modulation proved to be difficult challenges.In this paper,we propose and demonstrate a two-stage phase control method that can generate OAM beams with different topological charges from a CBC system.During the phase control process,the phase errors are preliminarily compensated by a deep-learning(DL)network,and further eliminated by an optimization algorithm.Moreover,by modulating the expected relative phase vector and cost function,all-electronic flexible programmable switching of the OAM mode is realized.Results indicate that the proposed method combines the characteristics of DL for undesired convergent phase avoidance and the advantages of the optimization algorithm for accuracy improvement,thereby ensuring the high mode purity of the generated OAM beams.This work could provide a valuable reference for future implementation of high-power,fast switchable structured light generation and manipulation.

Transverse mode instability mitigation in a high-power confined-doped fiber amplifier with good beam quality through seed laser control

In this work,a confined-doped fiber with the core/inner-cladding diameter of 40/250μm and a relative doping ratio of 0.75 is fabricated through a modified chemical vapor deposition method combined with the chelate gas deposition technique,and subsequently applied in a tandem-pumped fiber amplifier for high-power operation and transverse mode instability(TMI)mitigation.Notably,the impacts of the seed laser power and mode purity are preliminarily investigated through comparative experiments.It is found that the TMI threshold could be significantly affected by the seed laser mode purity.The possible mechanism behind this phenomenon is proposed and revealed through comprehensive comparative experiments and theoretical analysis.Finally,a maximum output power of 7.49 kW is obtained with the beam quality factor of approximately 1.83,which is the highest output power ever reported in a forward tandem-pumped confined-doped fiber amplifier.This work could provide a good reference and practical solution to improve the TMI threshold and realize high-power high-brightness fiber lasers.