An Experimental Study on Atmospheric Pressure Glow Discharge in Different Gases

Usually, the electrical breakdown of dielectric barrier discharge (DBD) at atmo-spheric pressure leads to a filamentary non-homogeneous discharge. However, it is also possible to obtain a diffuse DBD in homogeneous form, called atmospheric pressure glow discharge (APGD). We obtained a uniform APGD in helium and in the mixture of argon with alcohol, and studied the electrical characteristics of helium APGD. It is found that the relationship between discharge current and source frequency is different depending on the difference in gas gap when the applied voltage is kept constant. The discharge current shows an increasing trend with the increased frequency when gas gap is 0.8 cm, but the discharge current tends to decrease with the increased frequency when the gas gap increases. The discharge current always increases with the increased applied voltage when the source frequency is kept constant. We also observed a glow-like discharge in nitrogen at atmospheric pressure.

CLINICAL OBSERVATION ABOUT THE EFFECT OF BLOOD-LETTING OF JING-POINTS ON CEREBRAL BLOOD FLOW IN STROKE PATIENTS AT THE EARLY STAGE AND EXPERIMENTAL STUDY ON ITS MECHANISMS IN THE RABBIT

In this paper, the authors sum their research results about the effect of blood-letting of Jing (Well)-point on cerebral blood flow both in stroke patients and in experimental cerebral ischemia, cerebral hematoma and hypertension rabbits. In 30 cases of stroke (cerebral hemorrhage and cerebral infarction) patients, blood flow state of the anterior cerebral artery (ACA), middle cerebral artery (MCA) and the posterior cerebral artery (PCA), and the blood flow velocity of the bilateral vertebral artery (VA) and the basil artery (BA) are determined before and after pricking blood of the Twelve Jing-points. In experimental cerebral ischemia (by occlusion of the common carotid artery) rabbits, cerebral hematoma model rabbits and intravenous injection of noradrenaline induced hypertension rabbits, rheoencephalogram (REC) is detected before and after blood letting of the twelve "Jing"-points. In these 30 stroke patients, ultrasound Doppler examination’s results show that in 22 cases (73.33%) whose blood flow velocity decreases, after blood-letting of the 12 Jing-points, it increases significantly (P<0.01); in the rest 8 cases ( 26.67%) whose blood flow velocity speeds up, after treatment, it decreases evidently (P<0.01), showing a good dual-directional regulative effect of blood-letting therapy. In experimental cerebral ischemia rabbits, cerebral hematoma rabbits and hypertension rabbits whose REG lowers in the amplitude apparently (P<0.01), after blood letting stimulation of the 12 Jing-points, it increases at different degrees. Three patterns of stimulation as blood letting stimulation, pain stimulation and Jing-point stimulation, also the 3 factors of blood-letting therapy, may contribute to their effect on improvement of the cerebral blood flow. Somatic afferent nerve, sympathetic nerve of the vascular wall, central cholinergic nerve (M receptors) and adrenergic nerve (α receptors) participate in the effect of blood letting on cerebral blood flow.

STUDY OF A DIVICE ON THE WATCH FOR PARAMETER OF BLOOD PRESSURE AND ITS FLOW BY UNDAMAGED METHOD

ＳＴＵＤＹＯＦＡＤＩＶＩＣＥＯＮＴＨＥＷＡＴＣＨＦＯＲＰＡＲＡＭＥＴＥＲＯＦＢＬＯＯＤＰＲＥＳＳＵＲＥＡＮＤＩＴＳＦＬＯＷＢＹＵＮＤＡＭＡＧＥＤＭＥＴＨＯＤＳＴＵＤＹＯＦＡＤＩＶＩＣＥＯＮＴＨＥＷＡＴＣＨＦＯＲＰＡＲＡＭＥＴＥＲＯＦＢＬＯＯＤＰＲＥＳ...

Experimental study on dynamic gas adsorption

In order to predict the actual adsorption amount as gas adsorption reaches the equilibrium,this research designed a dynamic gas adsorption experiment under constant temperature and pressure,and also studied the isopiestic adsorption characteristics of coal samples with same quality but different sizes.Through the experiment,the study found the adsorption-time changing relationships under different pressures of four different size samples.After regression analysis,we obtained the functional relationship between adsorption and time.According to this,the research resulted in the actual adsorption amount when gas adsorption reaches the equilibrium.In addition,the current study obtained the relationship between adsorption and pressure as well as the effect of the coal size to the adsorption rate.These results have great theoretical and practical significance for the prediction of gas amount in coal seam and gas adsorption process.

Associations of soybean products intake with blood pressure changes and hypertension incidence: the China-PAR project

Background The relationships between dietary intake of soybean products and incident hypertension were still uncertain.This study aimed to illustrate the associations between intake of soybean products with risks of incident hypertension and longitudinal changes of blood pressure in a prospective cohort study.Methods We included 67,499 general Chinese adults from the Project of Prediction for Atherosclerosis Cardiovascular Disease Risk in China(China-PAR).Information about soybean products consumption was collected by standardized questionnaires,and study participants were categorized into the ideal(≥125 g/day)or non-ideal(<125 g/day)group.Hazard ratios(HRs)and corresponding 95%confidence intervals(95%CIs)for incident hypertension were calculated using Cox proportional hazard models.Among participants with repeated measures of blood pressure,generalized linear models were used to examine the relationships between soybean products consumption and blood pressure changes.Results During a median follow-up of 7.4 years,compared with participants who consumed<125 g of soybean products per day,multivariable adjusted HR for those in the ideal group was 0.73(0.67-0.80).This inverse association remained robust across most subgroups while significant interactions were tested between soybean products intake and age,sex,urbanization and geographic region(P values for interaction<0.05).The mean systolic and diastolic blood pressure levels were 1.05(0.71-1.39)mmHg and 0.44(0.22-0.66)mmHg lower among participants in the ideal group than those in the non-ideal group.Conclusions Our study showed that intake of soybean products might reduce the long-term blood pressure levels and hypertension incidence among Chinese population,which has important public health implications for primary prevention of hypertension.

Prevalence and Correlates of Elevated Blood Pressure in Chinese Children Aged 6-13 Years: a Nationwide School-Based Survey

Objective To estimate the prevalence of elevated blood pressure（EBP） in Chinese children and identify individual and family factors associated with EBP. Methods A nationwide cross-sectional study was conducted in 2010 using stratified cluster sampling. Participants＇ blood pressure was measured, and their parents completed a questionnaire on personal and family characteristics. Prevalence and correlates of EBP were assessed. Results Among a total of 24,333 participants, 20.2% of boys and 16.3% of girls had EBP. The prevalence of EBP increased with the ascending trend of waist circumference, Waist-to-height ratio, and body mass index. The adjusted prevalence ratios（aP Rs） for obese boys and girls were 2.50 and 2.97, respectively. Fewer urban boys（16.2%） had EBP than rural boys（21.7%）. Boys with a family history of hypertension were 12% more likely to have EBP. Children whose mothers received a college education tended to have lower likelihood of EBP; with an aP R was 0.85 among boys and 0.78 among girls. Conclusion EBP is common among obese students and those who have a family history of hypertension. A negative association between mothers＇ education levels and EBP risk in children was found.

Experimental Study on Tensile Behavior of Cement Paste, Mortar and Concrete under High Strain Rates

Effects of the strain rate on cement paste, mortar and concrete were studied. A modified SHPB testing technique with fl attened Brazilian disc（FBD） specimen was developed to measure the dynamic tensile stress-strain curve of materials. A pulse-shaped split Hopkinson pressure bar（SHPB） was employed to determine the dynamic tensile mechanical responses and failure behavior of materials under valid dynamic testing conditions. Quasi-static experiments were conducted to study material strain rate sensitivity. Strain rate sensitivity of the materials was measured in terms of the stress-strain curve, elastic modulus, tensile strength and critical strain at peak stress. Empirical relations between dynamic increase factor（DIF） and the material properties were derived and presented.

Implementation of a Multi-sampling-frequency System for RR-interval Timing and Blood Pressure Detection

In order to analyze the experimental cardiovascular signal with high accuracy, a system, integrating real-time monitoring and off-line further analysis, was developed and verified. The design, data processing and analysis methods as well as testing results are described. With 5 sampling frequency choices and 8 channel data acquisition, the system achieved high performances in beat-to-beat monitoring, signal processing and analysis. Tests were carried out to validate its performance in real-time monitoring, effectiveness of digital filters, QRS and blood pressure detection reliability, and RR-interval timing accuracy. The QRS detection rate was at least 99.46% for the records with few noises from MIT-BIH arrhythmia database using the algorithm for real-time monitoring, and no less than 96.43% for the records with some noises. In the condition that noise amplitude levels were less than 80%,the standard deviations for RR-interval timing were less than 1 ms with a generated ECG corrupted with various noises from MIT-BIH Noise Stress Test Database. Besides, the system is open for function expansion to meet further study-specific needs.

Effect of autologous blood donation on the central venous pressure, blood loss and blood transfusion during living donor left hepatectomy

AIM: Autologous blood donation (ABD) is mainly used to reduce the use of banked blood. In fact, ABD can be regarded as acute blood loss. Would ABD 2-3 d before operation affect the CVP level and subsequently result in less blood loss during liver resection was to be determined.METHODS: Eighty-four patients undergoing living donor left hepatectomy were retrospectively divided as group Ⅰ (GⅠ)and group Ⅱ (GⅡ) according to have donated 250-300 mL blood 2-3 d before living donor hepatectomy or not. The changes of the intraoperative CVP, surgical blood loss,blood products used and the changes of perioperative hemoglobin (Hb) between groups were analyzed and compared by using Mann-Whitney Utest.RESULTS: The results show that the intraoperative CVP changes between GⅠ (n = 35) and GⅡ (n = 49) up to graft procurement were the same, subsequently the blood loss,but ABD resulted in significantly lower perioperative Hb levels in GⅠ.CONCLUSION: Since none of the patients required any blood products perioperatively, all the predonated bloods were discarded after the patients were discharged from the hospital, It indicates that ABD in current series had no any beneficial effects, in term of cost, lowering the CVP, blood loss and reduce the use of banked blood products, but resulted in significant lower Hb in perioperative period.

Unveiling blood pressure-associated genes in aortic cells through integrative analysis of GWAS and RNA modification-associated variants

Background Genome-wide association studies(GWAS)have identified more than a thousand loci for blood pressure(BP).Functional genes in these loci are cell-type specific.The aim of this study was to elucidate potentially functional genes associated with BP in the aorta through the utilization of RNA modification-associated single-nucleotide polymorphisms(RNAm-SNPs).Methods Utilizing large-scale genetic data of 757,601 individuals from the UK Biobank and International Consortium of Blood Pressure consortium,we identified associations between RNAm-SNPs and BP.The association between RNAm-SNPs,gene expression,and BP were examined.Results A total of 355 RNAm-SNPs related to m6A,m1A,m5C,m7G,and A-to-I modification were associated with BP.The related genes were enriched in the pancreatic secretion pathway and renin secretion pathway.The BP GWAS signals were significantly enriched with m6A-SNPs,highlighting the potential functional relevance of m6A in physiological processes influencing BP.Notably,m6A-SNPs in CYP11B1,PDE3B,HDAC7,ACE,SLC4A7,PDE1A,FRK,MTHFR,NPPA,CACNA1D,and HDAC9 were identified.Differential methylation and differential expression of the BP genes in FTO-overexpression and METTL14-knockdown vascular smooth muscle cells were detected.RNAm-SNPs were associated with ascending and descending aorta diameter and the genes showed differential methylation between aortic dissection(AD)cases and controls.In scRNA-seq study,we identified ARID5A,HLA-DPB1,HLA-DRA,IRF1,LINC01091,MCL1,MLF1,MLXIPL,NAA16,NADK,RERG,SRM,and USP53 as differential expression genes for AD in aortic cells.Conclusion The present study identified RNAm-SNPs in BP loci and elucidated the associations between the RNAm-SNPs,gene expression,and BP.The identified BP-associated genes in aortic cells were associated with AD.

Theoretical and experimental investigation on vertical tank technology for sinter waste heat recovery

In the present work, the gas flow pressure drop and gas–solid heat transfer characteristics in sinter bed layer of vertical tank were studied experimentally on the basis of the homemade experimental setup. The gas flow pressure drop through the sinter bed layer was measured with different gas velocity and particle diameters, as well as the sinter and air temperatures. The influences of gas superficial velocity and particle diameter on the gas flow pressure drop and gas solid heat transfer in sinter bed layer were analyzed in detail. The revised Ergun's correlation and gas solid heat transfer correlation were obtained according to the regression analysis of experimental data. It is found that, the pressure drop of unit bed layer height gradually increases as a quadratic relationship with increasing the gas superficial velocity, and decreases as an exponential relationship with the increase of sinter particle diameter. For a given sinter temperature, the heat transfer coefficient in sinter bed layer increases with increasing the gas superficial velocity, and increases with decreasing the sinter particle diameter. In addition, the heat transfer coefficient also gradually increases with increasing the sinter temperature at the same gas superficial velocity and sinter particle diameter. The mean deviations between the experimental data obtained from this work and the values calculated by the revised Ergun's correlation and the experimental heat transfer correlation are 7.22% and 4.22% respectively, showing good prediction.

中华跌打丸活血化瘀作用的实验研究

目的:观察中华跌打丸对大鼠急性血瘀模型的体外血栓形成、血液黏度、血小板聚集率和对小鼠微循环障碍模型耳郭微循环的影响,评价中华跌打丸活血化瘀的作用。方法:通过注射肾上腺素加冰水刺激的方法建立大鼠急性血瘀模型,测定体外血栓形成和血液黏度;按照Born氏比浊法加入诱导剂诱导聚集测定大鼠血小板聚集率;尾静脉注射15%高分子右旋糖酐造成微循环障碍,观察小鼠耳郭各时段微动脉和微静脉管血液流速和血管管径的变化。结果:中华跌打丸可降低血瘀模型大鼠的血液黏度,在切变率150 S^(-1)、60 S^(-1)及5 S^(-1)下的全血黏度均显著降低(P<0.05),明显缩短血瘀模型大鼠血栓长度,减轻血栓湿重和干重(P<0.05,P<0.01);中华跌打丸具有抑制血小板聚集的作用,各剂量均能明显降低ADP诱导的大鼠血小板聚集率(P<0.05,P<0.01);中华跌打丸对高分子右旋糖酐所致小鼠耳郭微循环障碍有明显改善作用,于造模10 min、20 min、30 min时增加血液流速(P<0.05,P<0.01),扩大微动脉、微静脉管径(P<0.05,P<0.01),减轻红细胞聚集(P<0.05,P<0.01)。结论:中华跌打丸可明显改善血液黏度,抑制血小板聚集,改善微循环障碍,有较好的活血化瘀作用。

益气活血法对慢性心力衰竭大鼠心肌能量代谢及炎性因子的影响

目的:基于益气活血法探讨全真一气汤合补阳还五汤对慢性心力衰竭(CHF)大鼠心肌能量代谢及炎性因子的影响。方法:将30只健康雄性SD大鼠随机分为对照组、模型组和中药组,每组10只。采用腹腔注射阿霉素制备CHF模型,中药组给予全真一气汤合补阳还五汤干预。采用酶联免疫吸附法(ELISA)检测三磷酸腺苷(ATP)、二磷酸腺苷(ADP)、一磷酸腺苷(AMP)、白细胞介素6(IL-6)、N末端脑钠肽前体(NT-proBNP)水平;采用逆转录定量聚合酶链式反应(qRT-PCR)检测miR-21水平。结果:与对照组比较,模型组ATP、ADP、AMP降低(P<0.05),IL-6、NT-proBNP、miR-21表达均升高(P<0.05);与模型组比较,中药组ATP、ADP、AMP均升高(P<0.05),IL-6、NT-proBNP、miR-21表达均降低(P<0.05)。结论:益气活血法治疗可提高CHF大鼠心肌能量供应,减轻炎症反应,改善心功能。

芍药苷通过调控PI3K/AKT/mTOR信号通路对盐敏感性高血压大鼠血压和血管内皮功能的影响

目的:探讨芍药苷对盐敏感性高血压(SSH)大鼠血压和血管内皮功能的影响及其相关作用机制。方法:将50只Dahl盐敏感大鼠随机分为正常对照组(Control组)、高盐组(SSH组)、芍药苷组(PF组)、磷脂酰肌醇-3-激酶(PI3K)/蛋白激酶B(AKT)/哺乳动物雷帕霉素靶蛋白(mTOR)信号通路激活剂组(740Y-P组)、芍药苷+740Y-P组(PF+740Y-P组),每组10只。各组大鼠进行4周给药干预。采用动物无创血压仪测量大鼠尾动脉收缩压、舒张压;酶联免疫吸附法(ELISA)测定大鼠血清内皮素-1(ET-1)、一氧化氮(NO)、血栓素B2(TXB2)水平;苏木精-伊红(HE)染色观察大鼠主动脉病理变化;免疫组织化学染色检测大鼠主动脉组织中内皮型一氧化氮合酶(eNOS)表达;蛋白质免疫印迹法(Western Blot)检测大鼠主动脉组织中PI3K/AKT/mTOR信号通路蛋白表达。结果:与Control组比较,SSH组和740Y-P组大鼠主动脉血管内皮不完整,部分血管内皮脱落,且内膜明显增厚、外膜有大量沉积物;PF组大鼠主动脉血管病理损伤较SSH组明显减轻;PF+740Y-P组大鼠主动脉血管病理损伤较740Y-P组明显减轻,但较PF组明显加重。与Control组比较,SSH组大鼠收缩压、舒张压、血清ET-1、TXB2水平均升高,血清NO水平降低(P<0.05);主动脉组织中eNOS表达水平降低,磷酸化(p)-PI3K/PI3K、p-AKT/AKT、p-mTOR/mTOR比值均升高(P<0.05)。与SSH组比较,PF组大鼠收缩压、舒张压、血清ET-1、TXB2水平均降低,血清NO水平升高(P<0.05);主动脉组织中eNOS表达水平升高,p-PI3K/PI3K、p-AKT/AKT、p-mTOR/mTOR比值均降低(P<0.05)。与PF组比较,PF+740Y-P组大鼠收缩压、舒张压、血清ET-1、TXB2水平均升高,血清NO水平降低(P<0.05);主动脉组织中eNOS表达水平降低,p-PI3K/PI3K、p-AKT/AKT、p-mTOR/mTOR比值均升高(P<0.05)。与740Y-P组比较,PF+740Y-P组大鼠收缩压、舒张压、血清ET-1、TXB2水平均降低,血清NO水平升高(P<0.05);主动脉组织中eNOS表达水平升高,p-PI3K/PI3K、p-AKT/AKT、p-mTOR/mTOR比值均降低(P<0.05)。结论:芍药苷可以有效降低SSH大鼠血压,并改善大鼠血管内皮功能,其作用机制可能与抑制PI3K/AKT/mTOR信号通路激活有关。

牙种植同期植骨术围术期高血压的相关危险因素

目的:探索牙种植同期植骨术中,围术期高血压的特点及相关危险因素。方法:对北京大学口腔医院某门诊科室2021年9月至2022年8月的728例牙种植及植骨术患者进行回顾性队列研究,分析研究对象围术期高血压与性别、年龄、手术时长、植骨术式4种暴露因素的关联性。结果:牙种植同期植骨术中,收缩压平均波动幅度为9.93%±6.63%(最大值50.41%),舒张压平均波动幅度为12.45%±8.79%(最大值68.75%),平均动脉压平均波动幅度为10.02%±6.61%(最大值为49.48%)。围术期高血压的发病率为26.77%。男性、年龄≥60岁、手术时长>60 min是围术期高血压的危险因素(P<0.05),相对危险度(95%CI)分别为1.74(1.21~2.50)、2.35(1.54~3.58)和1.65(1.15~2.38)。引导性骨再生术、上颌窦内提升术、上颌窦外提升术3种植骨术式围术期高血压发病率差异无统计学意义(P>0.05),但不同植骨方式下围术期高血压的影响因素不同。引导性骨再生术围术期高血压的危险因素为男性、年龄≥60岁和手术时长>60 min(P<0.05);上颌窦内提升术围术期高血压的危险因素为年龄≥60岁(P<0.05);而对于上颌窦外提升术,男性、年龄≥60岁、手术时长>60 min都不是围术期高血压的危险因素(P>0.05)。结论:牙种植同期植骨术中存在一定的围术期高血压风险,男性、年龄≥60岁和手术时间>60 min对围术期高血压的影响程度与植骨方式有关。

芪参六味方抑制内皮-间质转化改善自发性高血压大鼠心肌纤维化的作用机制

目的:研究芪参六味方对自发性高血压大鼠(SHR)心肌纤维化的作用及机制。方法:构建SHR模型,将大鼠分为模型组、中药低浓度组、中药高浓度组、西药组,另以同龄Wistar-Kyoto(WKY)大鼠作为对照组,每组6只,干预12周。干预12周后进行心功能检测,计算心脏收缩功能指标左室射血分数(LVEF)、左室短轴缩短率(LVFS)及心脏舒张功能指标舒张早期跨二尖瓣血流速度(E)与舒张早期二尖瓣环运动幅度(E′)的比值E/E′;干预12周后处死大鼠,取左心室心肌组织,进行苦味酸-天狼猩红染色后观察心肌间质中胶原纤维总面积及Ⅰ型胶原与Ⅲ型胶原面积,计算两种胶原面积比值;蛋白质免疫印迹法(Western Blot)检测心肌组织中心肌纤维化相关指标Ⅰ型胶原、Ⅲ型胶原、基质金属蛋白酶-9(MMP-9)、基质金属蛋白酶抑制剂-1(TIMP-1)与内皮-间质转化(EndMT)相关血小板-血管内皮黏附分子(CD31)、血管内皮钙黏蛋白(VE-Cadherin)、α-平滑肌肌动蛋白(α-SMA)、人成纤维细胞特异蛋白1(FSP1)的表达水平;实时荧光定量聚合酶链式反应(RT-PCR)检测EndMT相关指标CD31、VE-Cadherin、α-SMA、FSP1 mRNA的表达水平。结果:干预12周后,与模型组相比,中药高剂量组降低心肌组织MMP-9蛋白表达(P<0.05),中药高剂量组与西药组均可降低心肌间质Ⅰ型胶原、Ⅲ型胶原蛋白表达水平(P<0.01),改善大鼠心脏舒张功能E/E′(P<0.01),降低EndMT相关蛋白α-SMA、FSP1蛋白表达及VE-Cadherin、α-SMA mRNA表达水平(P<0.05或P<0.01)。结论:芪参六味方可以减轻SHR大鼠心肌纤维化程度,改善心脏舒张功能,其作用机制可能与抑制EndMT有关。

新疆南疆地区农村人群基于不同指南定义的单纯舒张期高血压与心血管疾病的关联

目的探索新疆南疆地区农村人群中基于不同指南定义的单纯舒张期高血压(IDH)与心血管疾病(CVD)风险的关联。方法以新疆生产建设兵团第三师51团常住人口作为研究对象。根据2017年美国心脏病学会/美国心脏协会(ACC/AHA)高血压指南和2020年中国高血压指南对IDH的定义,分别纳入研究对象6834人和8960人。采用Log-rank检验比较不同指南定义的IDH患者和血压正常者CVD事件累积发病率的差异;使用Cox比例风险回归模型探索IDH与CVD风险的关联。结果ACC/AHA指南所定义的IDH患病率比中国指南定义者高5.4%。两种指南定义的IDH患者与血压正常者的CVD累积发病率差异均无统计学意义(ACC/AHA指南,χ2=0.07,P=0.80;中国指南,χ2=3.85,P=0.05);ACC/AHA指南定义的IDH患者CVD累积发病率较中国指南定义者低(6.14%vs 9.88%,χ2=5.22,P=0.02)。与血压正常者相比,中国指南定义的IDH与CVD发生风险的关联强度高于ACC/AHA指南,但差异无统计学意义,HR(95%CI)分别为:1.411(0.999~1.993)、1.037(0.788~1.364)。结论在新疆南疆农村人群中,应用2017年ACC/AHA指南定义的血压新阈值能够筛选出更多的IDH患者,有利于早期采取有效的防控措施。

Experimental study for frequency spectrum of turbulent boundary layer pressure fluctuation

An experimental study on TBL (turbulent boundary layer) pressure fluctuation frequeny spectrum of a revolution body is presented. With the measured results, a relation of convective frequency fo of the models is obtained. Relations of turbuleat wall-pressure fluctuation spectrum in transition region and development region to frequency and speed are obtained also