Finding of Gray Points on the Surface of the Sn-Fe Alloy Layer and Its Effects on the Corrosion Resistance of the Alloy Layer

After removing tin coating of tinplates offered by some steel works, we discovered massive, highly disperse gray points outspreading along rolling direction on the surface of the alloy layer. Morphology of the alloy layer was observed by scanning electron microscope (SEM), and many cavities of the alloy layer were found out in the gray point. After analyzing the composition of the alloy layer, we found that content of Fe in the gray points was more than that in the normal alloy layer. Moreover, corrosion resistance of the alloy layer declines with increase of amount of gray points. In addition, the hot-humidity testing was carried out for some plates whose surface has many gray points. After 14 days, there were many rust points occurring in the edge of gray points and in the small gray points. The morphology of rust points was observed by atomic force microscope (AFM). The reason why rust points generated in the edge of gray points and in the small gray points was discussed.

RESEARCH INTO THE LOW RESISTANCE OF MERIDIAN POINTS AND CLINICAL EXPERIMENTAL OBSERVATION

This thesis has further studied the low resistance of meridian points with a new in-strument called Model TZ-03 of resistance detector for Acupoints. Through experiments and clinicalobservation, the author found that the changes of skin resistances of points are closely related to thechanges of human physiology and pathology. The experiments also show that the factors which influ-ence the results are complicated and changeable in many ways. Therefore, the absolute values of theresistances of points are not precise and stahle f and the ratio of the resistance of bilateral point of thesame name is more re1iable. In healthy people, the resistances of the sarne points on two sides of thebody are similar, and there is much difference of these resistances among people with diseases.

Towards an Antimicrobial Stewardship Program in a Young Tertiary Hospital in Southern Nigeria: A Point Prevalence Survey of Antimicrobial Usage

Background: Antimicrobial resistance (AMR) is one of the top 10 global public health threats facing humanity and this burden is borne largely by low and middle-income countries. As part of efforts to combat AMR, the World Health Organization has identified Antimicrobial Stewardship as one of the strategic objectives of its global action plan on antimicrobial resistance. This survey aimed to observe antimicrobial prescribing and usage patterns in the Rivers State University Teaching Hospital with the purpose of identifying gaps to inform the specific antimicrobial stewardship interventions necessary to address our specific needs. Methodology: A point prevalence survey was conducted using the protocol and web-based automated data management system designed by the Global Point Prevalence Survey of Antimicrobial Consumption and Resistance, University of Antwerp, Belgium, in November 2021. Results: A total of 69 adult medical and surgical patients were surveyed;27 males and 18 females. Antimicrobial prevalence was 65.2%. Third generation cephalosporins (24.4%;33.3%), fluoroquinolones (17.8%;22.2%) and imidazole derivatives (20%;36.1%) were most prescribed on the medical and surgical wards. Antimicrobial guidelines were completely unavailable, most antimicrobials (93.8%) were prescribed empirically and 64.4% of these remained empirical after 72 hours of commencement. Conclusion: Antimicrobial stewardship interventions are necessary to minimize sub-optimal antimicrobial prescribing practices in our facility. Most critical are education on appropriate use of antimicrobials, support for development of antimicrobial guidelines, diagnostic stewardship, and the drive for improved use of the laboratory to guide antimicrobial prescriptions. The antimicrobial stewardship committee and team must drive this, having the requisite support from the management and prescribers, with the primary outcomes being reduced antimicrobial prevalence and improved antimicrobial prescription patterns.

THE NUMBERS OF JUMP LAYERS OF BOUNDARY VALUE PROBLEMS IN QUASILINEAR DIFFERENTIAL EQUATIONS

This paper discusses the numbers of jump layers of boundary value problems in quasilinear differential equations. In addition, the paper gives several examples to explain why the original equation must be rediscussed when the determinate function in reference [1 ] is a/ways equal to zero.

Junction Pressure Composing MethodCalculating the Total Resistance of Mine Ventilation Network

In mine ventilation network calculation, the total ventilatiou perameters, such as total specific resistance and total natural veutilatiou pressure of an overall mine ventilation system, play an important role on selecting main fan and regulating its operating point. This paper explains the critical effect of network’ s total parameter calculation on the above two aspects and presents a new method, the junction pressure composing method(JPC method), which can be applied to calculate the total resistance.of an overall, complex and multi-fan ventilation network. Based on the total ressistance and airflow rate of main fan, total specific resistance of a natwork is easily calculated. This method gets rid of those shortcomings in the route airflow working mathod(RAW method), greatly improves computing speed and adaptability, and can calculate the total parameters of a mine ventilation network rapidly and conveniently. This method is proved to be correct and reliable by example tests.

The Effects of a Complex Training Protocol on Vertical Jump Performance in Male High School Basketball Players

The purpose of this study was to investigate the effects of CT （complex training） on VJ （vertical jump）. It was hypothesized that VJ height would be enhanced through CT and even greater increases would occur as a result of higher intensity resistance exercise. Twenty male high school basketball players were divided into two training groups： a H1 （high intensity）, low repetition group and a medium intensity, HR （high repetition） group. Each training group trained twice per week for six weeks. Training protocols involved three sets of 8-10 squat repetitions （80%-85% 1RM （repetition maximum）） for the HI group followed by ten countermovement jumps and thre.e sets of 12-15 squat repetitions （60%-70% 1RM） for the HR group followed by ten countermovement jumps. A three minute rest period was utilized between each set. Participants were tested at weeks 1, 3, and 6. The results of this study revealed that there was not a significant difference between the two CT protocols with respect to VJ （p = 0.077）. At week 6 both groups increased VJ significantly; HI group （4.0 ±1.8 cm, p 〈 0.01） and the HR group （2.7 ± 1.6 cm, p 〈 0.01）. Within the parameters of this study CT with either HI or HR protocols are effective at improving VJ.

Mechanisms of Helicobacter pylori antibiotic resistance:An updated appraisal

Helicobacter pylori(H. pylori) antibiotic resistance is the main factor affecting the efficacy of the current eradicating therapies. The aim of this editorial is to report on the recent information about the mechanisms accounting for the resistance to the different antibiotics currently utilized in H. pylori eradicating treatments. Different mechanisms of resistance to clarithromycin,metronidazole,quinolones,amoxicillin and tetracycline are accurately detailed(point mutations,redox intracellular potential,pump efflux systems,membrane permeability) on the basis of the most recent data available from the literature. The next hope for the future is that by improving the knowledge of resistance mechanisms,the elaboration of rational and efficacious associations for the treatment of the infection will be possible. Another auspicious progress might be the possibility of a cheap,feasible and reliable laboratory test to predict the outcome of a therapeutic scheme.

Effectiveness and time-course adaptation of resistance training vs. plyometric training in prepubertal soccer players

Purpose:This study aimed to assess the effectiveness and time course for improvements in explosive actions through resistance training(RT)vs.plyometric training(PT)in prepubertal soccer players.Methods:Thirty-four male subjects were assigned to:a control group(n=11);an RT group(5 regular soccer training sessions per week,n=12);a PT group(3 soccer training sessions and 2 RT sessions per week,n=11).The outcome measures included tests for the assessment of muscle strength(e.g.,1 repetition maximum half-squat test),jump ability(e.g.,countermovement jump,squat jump,standing long jump,and multiple 5 bounds test),linear speed(e.g.,20m sprint test),and change of direction(e.g.,Illinois change of direction test).Results:The RTG showed an improvement in the half-squat(△=13.2%;d=1.3,p<0.001)and countermovement jump(△=9.4%;d=2.4,p<0.001)at Week 4,whereas improvements in the 20-m sprint(△=4.2%;d=1.1,p<0.01);change of direction(CoD)(△=3.8%;d=2.1,p<0.01);multiple 5 bounds(△=5.1%;d=1.5,p<0.05);standing long jump(△=7.2%;d=1.2,p<0.01);squat jump(△=19.6%;d=1.5,p<0.01);were evident at Week 8.The PTG showed improvements in CoD(△=2.1%;d=1.3,p<0.05);standing long jump(△=9.3%;d=1.1,p<0.01);countermovement jump(△=16.1%;d=1.2,p<0.01);and squat jump(△=16.7%;d=1.4,p<0.01);at Week 8 whereas improvements in the 20-m sprint(△=4.1%;d=1.3,p<0.01);and multiple 5 bounds(△=7.4%;d=2.4,p<0.001);were evident only after Week.The RT and PT groups showed improvements in all sprint,CoD,and jump tests(p<0.05)and in half-squat performance,for which improvement was only shown within the RTG(p<0.001).Conclusion:RT and PT conducted in combination with regular soccer training are safe and feasible interventions for prepubertal soccer players.In addition,these interventions were shown to be effective training tools to improve explosive actions with different time courses of improvements,which manifested earlier in the RTG than in the PTG.These outcomes may help coaches and fitness trainers set out clear and concise goals of training according to the specific time course of improvement difference between RT and PT on proxies of athletic performance of prepubertal soccer players.

Influence of Organ Pathology on the Electrical Parameters in Organ Projection Areas of the Skin

Pathology of an internal organ causes significant rectification of electrical currents （diode phenomenon） in related skin areas - organ projection areas （OPAs）, once the resistance ‘breakthrough effect＇ has been induced in the skin. Also, the impedance of the diseased organ＇s projection areas is increased. The aim of this double-blind study was to confirm these phenomena statistically using a broad spectrum of measuring parameters. Skin impedance vs. measurement frequency, skin impedance vs. applied voltage, and skin resistance vs. voltage were evaluated at 335 auricular OPAs related to the healthy internal organs and 203 auricular OPAs related to the diseased organs. These measurements confirmed that the skin electrical characteristics of specific locations are dependent on the health state of the corresponding internal organs. It was found that the impedance of OPAs corresponding to the healthy internal organs equals 185 ＋ 291 k,Q at 10Hz and decreases to 64 ± 49 kΩ at 10kHz; and that the impedance of OPAs related to the diseased organs equals 7.5 ± 2.2 MΩ at 10Hz and 99 ± 50kΩ at 10kHz. The disparity of the impedances between the healthy and diseased organs related OPAs is greater at higher potentials. The skin resistance, when measured with a negatively polarized point electrode, undergoes a rapid resistance decrease of approximately two orders of magnitude, if the applied current is sufficient. After this reversible ‘breakthrough effect＇ is obtained the skin exhibits rectification. The degree of rectification is low for OPAs related to the healthy organs. For OPAs related to the diseased organs, the resistance measured with a positive polarisation of measuring electrode could be five times greater than the resistance measured at the same voltage with the same but negatively polarised electrode. The disparity between the resistance measured with a negatively and with a positively polarised electrode at OPAs related to the diseased organs was greater at higher measurement voltages. The influence of organ pathology on the electrical parameters of related OPAs does not depend on the kind of internal organ and is not affected by the etiology of pathology. The degree of rectification or difference in impedance is proportional to the extent of the pathological process within the related organ.

Localization of Auricular Projection Area of the Liver and Its Use in the Monitoring of Viral Hepatitis

Background： Pathology of an internal organ causes significant rectification of electrical currents （diode phenomenon） in related skin areas once the resistance ＇breakthrough effect＇ has been induced in the skin. Objective： Localization of auricular projection area of the liver and evaluation of its usefulness in the monitoring of viral hepatitis. Design, Patients and Setting： Comparative study of the degree of electrical rectification measured at various spots in the auricular concha region, in 19 inpatients with hepatitis B and 15 clinically healthy volunteers, at the Department of Infectious Diseases, Provincial Teaching Hospital, Tychy, Poland. Intervention： Evaluation of electrical rectification at various spots on the auricular concha using a ＂rectification ratio＂ that quantifies the degree of rectification （normal range： 0-60%）. Main outcome measure： The location of the skin area where a statistically significant difference existed between the rectification ratios was observed in patients （82±12% at the time of the ＇peak period＇） versus controls （42±8%）. Results： A location was identified on the ear auricle where the electrical rectification phenomenon demonstrated a dependence on the presence of hepatitis. Conclusions： Liver projection area exists on the ear auricle which is located within the region of cymba conchae, next to anthelix and the cavity of concha. The existence of viral hepatitis causes this skin area to show a higher degree of electrical rectification once the skin resistance ＇breakthrough effect＇ has been induced. Evaluation of the rectification phenomenon of the liver proiection area provides a method of non-invasive monitoring of viral hepatitis.

Low temperature J-resistance curve determination of asphalt concrete using wavelet-Radon transform

A single specimen test using the three point single edge notched beam configuration at low temperatures for obtaining hot mix asphalt （HMA） resistance curves is developed.Resistance curves are obtained for mixtures at six temperature levels of＋5,0,-5,-10,-15,and-20 ℃ and three binder contents of 4％,4.5％,and 5％.Crack extension increments during the test are measured by means of an image processing technique using Radon transform and feature extraction.All the specimens exhibit a rising R-curve,indicating ductility and toughening mechanisms in the ductile-quasi brittle fracture of the mixture.It is observed that the reduction of temperature results in a further tendency of the mixture for unstable crack growth and less subcritical crack length.It is also shown that using the binarization process,an automatic index can be developed that can represent the extent of brittleness and extent of the low temperature in which the cracking has occurred.

Parasitic Effects on the Performance of DC-DC SEPIC in Photovoltaic Maximum Power Point Tracking Applications

This paper presents an analysis of the effect of parasitic resistances on the performance of DC-DC Single Ended Pri- mary Inductor Converter (SEPIC) in photovoltaic maximum power point tracking (MPPT) applications. The energy storage elements incorporated in the SEPIC converter possess parasitic resistances. Although ideal components significantly simplifies model development, but neglecting the parasitic effects in models may sometimes lead to failure in predicting first scale stability and actual performance. Therefore, the effects of parasitics have been taken into consideration for improving the model accuracy, stability, robustness and dynamic performance analysis of the converter. Detail mathematical model of SEPIC converter including inductive parasitic has been developed. The performance of the converter in tracking MPP at different irradiance levels has been analyzed for variation in parasitic resistance. The converter efficiency has been found above 83% for insolation level of 600 W/m2 when the parasitic resistance in the energy storage element has been ignored. However, as the parasitic resistance of both of the inductor has increased to 1 ohm, a fraction of the power managed by the converter has dissipated;as a result the efficiency of the converter has reduced to 78% for the same insolation profile. Although the increasing value of the parasitic has assisted the converter to converge quickly to reach the maximum power point. Furthermore it has also been observed that the peak to peak load current ripple is reduced. The obtained simulation results have validated the competent of the MPPT converter model.

End points of clinical trials in metastatic castration-resistant prostate cancer:A systematic review

AIM： To review the defnition and performance of the commonly used end points in trials of systemic thera-pies in metastatic castration-resistant prostate cancer patients. METHODS： A literature search was undertaken on PubMed database to identify studies meeting estab-lished criteria, with the aim of selecting randomized clinical trials and study definition and performance of their end points. The end points were grouped into three categories： overall survival （OS）, time-to-event end points, and response end points. A special analysis was performed for secondary end points of the studies which documented a beneft in OS in the experimental arm. Finally, publishes analyses for surrogacy of the in-cluded end points were also reported. RESULTS： OS, time-to-event and response end points in 31 selected trials were analyzed. OS was the pri-mary end point in 14 trials, and the secondary end point in 17. A time-to-event end point was the primaryend point in 8 studies, and the secondary end point in 22; the most reported time-to-event end points were composite end points, and the events changed among trials. A response end point was the primary end point in 9 studies, in 3 it was prostate-specifc antigen （PSA）-related, in 3 pain-related and in 3 mixed. A response end point was the secondary end point in 19 studies： PSA response and radiologic response were the most frequently used secondary end points in 19 and 11 tri-als, respectively, while pain response was used in 5 studies.CONCLUSION： A homogeneous defnition of progres-sion in future trials is mandatory. Among response end points, pain-response and PSA-response appear to be the most reliable.

复杂城市低空无人机安全风险评估与三维路径规划

针对复杂城市环境内低空无人机飞行安全与效率亟待提升的问题,提出了复杂城市低空无人机安全风险评估与三维路径规划方法。首先,设计了无人机越界冲突率、缓冲空域占比指标,建立了无人机地理围栏安全缓冲间距优化模型,对最佳缓冲间距和栅格粒度进行了标定;然后,构建了由人口密度层、遮蔽层和障碍层构成的无人机风险地图,建立了弹道下降和失控滑行两种模式下的无人机对地风险评估模型,生成了精细化、组合化的城市低空概率风险地图;最后,综合利用地理围栏、概率风险地图和跳点搜索算法,对无人机三维路径进行了初始规划和优化重构。结果表明:弹道下降模式的伤亡风险是失控滑行下降模式的5~75倍;与A*算法相比,跳点搜索算法有效减少了飞行路径的转弯数量,缩短了求解时长,更适合规划无人机飞行路径;与不采用风险地图的方法相比,基于风险地图的无人机路径规划减少了50%的较高风险节点,相应的路径长度仅增加了7.2%和11.4%,整体路径节点的伤亡风险明显降低。研究成果可为复杂城市低空无人机飞行计划制定及安全运行监管提供理论依据和方法支撑。

基于改进蚁群算法的移动机器人路径规划

针对传统蚁群算法在移动机器人路径规划中存在搜索盲目性、收敛速度慢及路径转折点多等问题,提出了一种基于改进蚁群算法的移动机器人路径规划算法。首先,利用跳点搜索(Jump Point Search,JPS)算法不均匀分配初始信息素,降低蚁群前期盲目搜索的概率;然后,引入切比雪夫距离加权因子和转弯代价改进启发函数,提高算法的收敛速度、全局路径寻优能力和搜索路径的平滑程度;最后,提出一种新的信息素更新策略,引入自适应奖惩因子,自适应调整迭代前、后期的信息素奖惩因子,保证了算法全局最优收敛。实验仿真结果表明,在不同地图环境下,与现有文献结果对比,该算法可以有效地缩短路径搜索的迭代次数和最优路径长度,并提高路径的平滑程度。

豫南地区菱斑食植瓢虫室内外种群抗寒性研究

为明确豫南地区菱斑食植瓢虫(Epilachna insignis)的抗寒能力与低温驯化反应,利用过冷却点测定仪测定其过冷却点和结冰点,并分析其频次分布。结果表明,菱斑食植瓢虫卵的过冷却点(-23.69℃)和结冰点(-21.31℃)最低;4龄幼虫的过冷却点(-6.77℃)和结冰点(-3.93℃)最高;菱斑食植瓢虫雌雄成虫过冷却点和结冰点差异显著,雄成虫过冷却点(-19.61℃)和结冰点(-17.67℃)均显著低于雌成虫过冷却点(-14.23℃)和结冰点(-11.49℃),且室内种群雌雄成虫过冷却点和结冰点均与自然种群无显著差异。同一虫龄、虫态不同个体间过冷却点与结冰点的变化均符合正态分布。抗寒驯化处理结果表明,随处理温度的降低,雌成虫的死亡率逐渐升高,各冷藏驯化处理过冷却点差异均不显著,以8℃冷藏驯化结冰点最低(-13.99℃)。

低成本手持式稠密点云采集系统

针对现有室内外场景无法使用低成本便携式LiDAR很好地采集高稠密度点云数据的问题,本文研究设计了一种对低成本LiDAR和IMU传感器在硬件层面进行组合的低成本手持式稠密点云采集系统。采用简化残差计算量后的Faster-LIO当作里程计,通过传感器紧耦合的方式,将LiDAR和IMU之间的外参矩阵作为优化量,在采集的过程中进行实时优化以获得准确的相对位姿,从而得到满足精度要求的稠密点云。本文方法与经典的基于LOAM特征的LiDAR里程计及RTK里程计进行对比,试验结果表明,本文方法是有效的,手持式旋转激光雷达扩增了LiDAR的视野,而且对采用的里程计算法进行了改进,在减少算力要求降低成本的同时,大幅度降低了LiDAR和IMU等设备安装时无法避免的相互扰动问题,能较好地完成对场景稠密点云的采集及初步重建。

参芪益心汤治疗心力衰竭合并利尿剂抵抗患者的临床疗效及对其心功能、NT-proBNP水平的影响

目的 探讨参芪益心汤加减治疗心力衰竭合并利尿剂抵抗患者的疗效。方法 选取2021年12月—2022年12月期间黑龙江中医药大学附属第一医院收治的心力衰竭合并利尿剂抵抗患者100例作为研究对象,按照随机数字表法分为对照组和试验组,每组各50例。对照组予常规治疗,试验组在对照组基础上加用参芪益心汤,两周为1个疗程,两组患者均治疗4周。观察比较两组患者治疗前后心功能指标[左心室舒张末期内径(Left ventricular end-diastolic diameter,LVDD)、左房内径(Left atrial diameter,LAD),计算左室射血分数(Left ventricular ejection fraction,LVEF)]、血清指标[N端脑钠肽前体(N-terminal pro-brain natriuretic peptide,NT-proBNP)、肌钙蛋白T(Cardiac troponin T,CTnT)、肌酸磷化脢同功脢(Creatine kinase isoenzyme,Ck-MB)]、中医证候积分,比较两组患者临床疗效及不良反应。结果 治疗后两组患者心功能LVDD、LAD水平均较治疗前降低,LVEF水平均较治疗前升高,差异有统计学意义(P<0.05);且试验组LVDD、LAD水平均明显低于对照组,LVEF水平明显高于对照组,差异有统计学意义(P<0.05)。治疗后两组患者NT-proBNP、CTnT、Ck-MB水平均较治疗前降低,差异有统计学意义(P<0.05);且试验组NT-proBNP、CTnT、Ck-MB水平均明显低于对照组,差异有统计学意义(P<0.05)。治疗后两组患者心悸、气短、气喘、胸闷评分均较治疗前降低,差异有统计学意义(P>0.05);且试验组心悸、气短、气喘、胸闷评分均明显低于对照组,差异有统计学意义(P<0.05)。治疗后试验组总有效率96.00%(48/50)高于对照组72.00%(36/50),差异有统计学意义(P<0.05)。治疗期间,两组患者不良反应发生率比较,差异无统计学意义(P>0.05)。结论 应用参芪益心汤能够显著改善心功能,缓解临床症状,疗效显著,值得临床应用。

考虑电磁-热-结构耦合的并沟线夹温升特性分析及验证

为更准确地研究并沟线夹的温升特性,分析了导线与并沟线夹之间接触点的实际分布特征,建立了并沟线夹的三维电磁、热、结构多物理场耦合模型。基于结构场分析线夹与导线安装和发生热膨胀后导线的接触压力,并计算接触电阻,通过电磁-热耦合得到线夹的电流密度及温度分布规律,探明最高温度的具体位置。分析了不同载流量与螺栓松脱程度对线夹最高温度的影响。研究结果表明:当电流流经并沟线夹系统时,导线与线夹本体接触点界面外侧的电流密度最大,造成的发热最严重;载流量越小,螺栓松脱对线夹的最高温度影响越小,反之,螺栓松脱对线夹的最高温度影响越大;相对误差在3%内,模型具有较高的准确性。

基于改进跳点搜索和蚁群算法的机器人多目标点巡检规划

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