Driving pressure:A useful tool for reducing postoperative pulmonary complications

The operating room is a unique environment where surgery exposes patients to non-physiological changes that can compromise lung mechanics.Therefore,raising clinicians’awareness of the potential risk of ventilator-induced lung injury(VILI)is mandatory.Driving pressure is a useful tool for reducing lung complications in patients with acute respiratory distress syndrome and those undergoing elective surgery.Driving pressure has been most extensively studied in the context of single-lung ventilation during thoracic surgery.However,the awareness of association of VILI risk and patient positioning(prone,beach-chair,parkbench)and type of surgery must be raised.

Pressure assessment in intercavernous embedding of bulboperineal urethra for treatment of urinary incontinence after prostatic operation

Aim: To put forward criteria for the pressure assessment in the operation of intercavernous embedding of bulboper-ineal urethra for the treatment of urinary incontinence after prostatic operation. Methods: A F14 urethral catheter isinserted during the operation and upon suturing the corpora cavernosa centrally, the catheter is slowly pushed in andpulled out in order that the operator feels a certain degree of close-fit resistance. The degree of tightness of the stitches,which regulate the compression pressure, is adjusted in accordance with this close-fit sensation. To further ascertain theadequacy of the force of compression, the bladder is filled with 300 ml physiological saline and observe the appropriate-ness (size and continuity) of the outflow stream when the lower abdomen is depressed with a pressure of 80 - 90 cmH_2O. The operation was given to six patients suffered from urinary incontinence for 20 or more months after prostaticoperation. Results: Five cases achieved complete recovery, while the therapeutic effect of the 6th one was not sat-isfactory . A second stage operation was carried out 3 months later with the addition of one more stitch both proximallyand distally to reinforce the compression force. The condition was improved dramatically. The follow-up period aver-aged 3.5 years. Conclusion; The adequacy of the compression pressure exerted by the juxtaposed corpora cavernosais the key point determining the outcome of the operation. The measures for assessing the compression pressure suggest-ed by the authors are helpful in obtaining the good results of the present paper (6/6 success) as compared with 25/34success in the previous report. (Asian J Androl 2001 Sep; 3: 235 — 237)

Research on resonance parameters matching based on partitioned operation method of atmospheric pressure plasma reactor array

Matching optimization of resonant parameters among the high power inverters,low power transformers and plasma reactors have significant effects on the performance and output of the reactor array when applying the partitioned operation method.In this paper,the Matlab/Simulink electrical model was established based on the method of partitioned operation.The matching relation between resonant parameters is analyzed on the basis of experimental result.As a consequence,transformer leakage inductance and working frequency are the important parameters influencing the operational efficiency of system,leakage inductance of transformer should be adjusted based on the equivalent capacitance of plasma reactor to realize the matching optimization of resonant parameters.

Self-healing Au/PVDF-HFP composite ionic gel for flexible underwater pressure sensor

Ionic gels can be potentially used in wearable devices owing to their high humidity resistance and non-volatility.However,the applicability of existing ionic gel pressure sensors is limited by their low sensitivity.Therefore,it is very import-ant to develop an ionic gel pressure sensor with high sensitivity and a wide pressure detection range without sacrificing mechan-ical stretchability and self-healing ability.Herein,we report an effective strategy for developing pressure sensors based on ion-ic gel composites consisting of high-molecular-weight polymers,ionic liquids,and Au nanoparticles.The resulting capacitive pressure sensors exhibit high pressure sensitivity,fast response,and excellent self-healing properties.The sensors composed of highly hydrophobic polymers and ionic liquids can be used to track underwater movements,demonstrating broad application prospects in human motion state monitoring and underwater mechanical operations.

Effects of operating parameters on oxidative coupling of methane over Na-W-Mn/SiO_2 catalyst at elevated pressures

The effects of operating parameters on oxidative coupling of methane （OCM） over Na-W-Mn/SiO2 catalyst have been studied at elevated pressures of 0.2, 0.3 and 0.4 MPa under low gaseous hourly space velocity （GHSV） and low temperature conditions. Experimental results show that when the operating pressure is increased, C2＋ yield slightly decreases, while the maximum ratio of ethylene to ethane remains unchanged. Moreover, it has been found empirically that increase of pressure does not affect the catalyst behavior permanently, the catalyst recovers its original low pressure performance without hysteresis behavior by reducing the pressure. Under the investigated conditions, when oxygen is completely consumed, the increase of GHSV leads to improvement in C2 selectivity, while C3＋ and COx selectivities decrease slightly. The C2＋ selectivity increases by increase of nitrogen diluent in the feed, but the C3＋ hydrocarbons selectivities decrease with increase of nitrogen since it is possible that further dilution at high pressure may reduce the probability of collision between CH3 and C2＋ hydrocarbons. During the stability test at high pressure, the catalyst performance remains unchanged throughout the 20 h running. The fresh and used catalysts were characterized using XRD, SEM and N2 adsorption-desorption methods. It was found that the phase transformation of the support from α-cristobalite to tridymite and quartz does not have obvious effect on catalyst performance at high pressure.

Mechanical Analysis of a Multi-Test String in High-Temperature and High-Pressure Deep Wells

The mechanical behavior of the test string in deep wells is generally relatively complex as a result of the high temperature and high pressure,severe dogleg and buckling effects,which in some circumstances can even lead to string failure.Traditional computational methods for the analysis of these behaviors are often inaccurate.For this reason,here a more accurate mechanical model of the test string is introduced by considering variables such as temperature,pressure,wellbore trajectory,and buckling,as well as combining them with the deformation and string constraint conditions brought in by changes in temperature and pressure during the tripping,setting,and test operations.The model is validated by applying it to a specific high-pressure gas well(located in Northeast Sichuan).

Effects of operating pressure on the key parameters of coal direct chemical looping combustion

Techno-economic development of chemical looping combustion （CLC） process has been one of the most pursued research areas of the present decade due to its ability to reduce carbon foot print during utilization of coal to generate energy. Based on a 2D computational fluid dynamics model, the present work provides a computational approach to study the effect of operating pressure--a key parameter in designing of CLC reactors, on optimum operating conditions. The effects of operating pressure have been examined in terms of reactors temperature, percentage of fuel conversion and purity of carbon dioxide in fuel reactor exhaust. The simulated results show qualitative agreement with the trends obtained by other investigators during experimental studies.

Study on Influence Factors of Pressure Injury Risk in the Elderly Inpatients with Kidney Disease Based on LASSO Regression

Objective: This paper aims to explore clinical status and related influence factors of pressure injury (PI) in the elderly inpatients with kidney disease, so as to provide reference for the prevention and treatment of PI in the elderly inpatients with kidney disease. Methods: Retrospective collection method is adopted to collect 158 clinical cases of the elderly inpatients with kidney disease aged ≥ 60 in the Nephrology Department, the First Affiliated Hospital of Jinan University from January 2017 to December 2019, and then least absolute shrinkage and selection Operator (LASSO) regression analysis is used to analyze 17 possible influence factors;finally Logistic regression model is established to analyze and screen influence factors of risk. Results: 1) Among 158 elderly inpatients with medium and high risk of PI, the incidence of PI is 20.25%;the most common stage of injury is stage I (42.5%);sacrococcygeal (60%) is the high-risk site of pressure injury. 2) LASSO regression analysis shows that history of present respiratory infection/respiratory failure (β = 1.2714. P < 0.05) and hospitalization time (β = 0.4177. P < 0.05) are independent factors influencing PI risk in the elderly inpatients with kidney disease. Conclusion: The elderly patients with kidney disease and PI risk are the high incidence population of hospital acquired PI;for the elderly inpatients with kidney disease and having respiratory infection history or respiratory failure, prolonged hospitalization will significantly increase the risk of PI. Therefore, targeted preventive and control measures should be taken to reduce the incidence of PI.

Analysis of pressure pulsation mechanism and dynamic characteristics of axial piston pump

The pressure pulsation of axial piston pump is not only an important cause of rotation speed fluctuation,vibration noise and output stability of the hydraulic system,but also the main information source for obtaining fault information.Hydraulic system is characterized by strong noise interference,which leads to low signal-to-noise ratio(SNR)of detection signals.Therefore,it is necessary to dig deep into the system operating state information carried by pressure signals.Firstly,based on flow loss mechanism of the plunger pump,the mapping relationship between flow pulsation and pressure pulsation is analyzed.After that,the pressure signal is filtered and reconstructed based on standard Gabor transform.Finally,according to the time-domain waveform morphology of pressure signal,four characteristic indicators are proposed to analyze the characteristics of pressure fluctuations under different working conditions.The experimental results show that the standard Gabor transform can accurately extract high-order harmonics and phase frequencies of the signal.The reconstructed time-domain waveform of pressure pulsation of the axial piston pump contains a wealth of operating status information,and the characteristics of pulsation changes under various working conditions can provide a new theoretical basis and a method support for fault diagnosis and health assessment of hydraulic pumps,motors and key components.

Model Based Pressure Control of a Push Belt Continuously Variable Transmission

A Continuously Variable Transmission (CVT) is a type of transmissions that provides a continuous range of speed ratios, thus it allows increasing the overall powertrain efficiency by running the engine at the optimal operating points. This paper investigates implementing a model based hydraulic pressure controller to achieve the desired CVT gear ratio. A map of desired gear ratios was estimated using the Optimal Operating Line (OOL) strategy, which minimizes the engine fuel consumption according to a defined cost function and a set of systems constraints. The controller was implemented in a complete vehicle model that includes driver, powertrain and road load models. The model was subjected to two different driving cycles and the results demonstrate the effectiveness of the control strategy and the pressure controller in keeping the engine at the most efficient operating regions.

Research of Pipeline Pressure Based on the Reliability Theory

The former gas pipeline operating pressure transmission determined mostly according to the determined formula into the corresponding pipeline parameters are obtained, and the parameters of the actual pipeline due to many reasons, such as measurement error, production batch, etc., is not a fixed value. This paper on pipeline integrity established limit state equation, using Monte Carlo method to calculate the gas pipeline in different pressures of reliability, according to the API （American Petroleum Institute） 579 recommended target reliability to determine the operating pressure of the different regions, and design coefficient method, the calculated results are compared, results of calculation reliability is more reasonable and improve the delivery pressure of the area, the pipeline safety management provides the basis.

挂牌督办:中国式行政督查制度

为有效应对日趋复杂的安全治理形势,发轫于社会治安治理而后被推广至生态环保、安全生产等领域的挂牌督办制度,将中国特色的督查机制创造性融入复杂的治理场景之中,取得了显著的治理成效,成为近年来被频繁使用和研究的中国公共管理关键词。挂牌督办所蕴含的政治压力、社会压力和时间压力形成了强大的政治势能,促使地方政府及其职能部门等督办客体迅即强化其政治执行力、组织协同力和社会回应力,进而在较短的时间内完成中央政策目标、提升安全治理效能。同时,我们应秉持理性科学的态度客观评估挂牌督办的治理绩效,在厘清其效能边界的基础上,以更高质量的研究工作清晰识别其运行的底层逻辑,为确保挂牌督办制度始终发挥正向功能提供对策参考。

陕西省手术室护理人员预防术中获得性压力性损伤知信行的现况调查

目的:调查陕西省手术室护理人员对预防术中获得性压力性损伤的知信行现状,分析其影响因素,为临床开展预防术中获得性压力性损伤知识培训提供依据。方法:采用便利抽样法,于2023年6月—8月选取陕西省317家医院的3642名手术室护理人员为调查对象,采用自行编制的手术室护理人员预防术中获得性压力性损伤知信行问卷进行调查。结果:手术室护理人员预防术中获得性压力性损伤知识、态度、行为的得分为(44.93±9.07)分、(43.84±7.24)分、(75.88±11.32)分,得分率分别为81.69%、87.68%、89.27%。培训次数、医院等级、科室类别、工作年限正向影响知识维度得分(P<0.05);培训次数、职称、医院等级正向影响态度维度得分(P<0.05);培训次数、医院等级、职称正向影响行为维度得分(P<0.05)。结论:手术室护理人员对术中获得性压力性损伤预防的态度和行为较为积极,但知识水平有待进一步提高。应充分发挥三级医院的辐射作用,从增加有效培训次数并合理利用护士个人经验着手,提高手术室护理人员术中获得性压力性损伤预防水平。

新疆高校新生身体形态指标和血压的特征及关联性研究

目的了解新疆高校新生身体形态指标与血压的特征及差异性,分析其关联性,为新疆高校新生高血压防治和干预提供参考依据。方法采用随机抽样对新疆4所高校的1853名18~21岁大学新生进行身体形态、腰围、臀围、血压等指标测量,根据受试者血压分为正常血压组和血压偏高组,分析不同性别、民族、年龄段新生血压的差异;统计学方法采用χ^(2)检验、Pearson相关性分析、Logistic回归分析及受试者操作特征(receiver operating characteristic,ROC)曲线分析。结果女生的体脂率(percent body fat,PBF)和体脂量高于男生[(24±8)%与(18±7)%,t=-17.95,P<0.01);(18±7)kg与(14±7)kg,t=-4.27,P<0.01],其他指标均低于男生;除体脂率外,汉族学生的身体形态指标均高于少数民族(P值均<0.01)。男生的血压偏高检出率高于女生[51.5%(538/1044)与42.4%(343/809),χ^(2)=15.250,P<0.01];汉族血压偏高检出率高于少数民族[59.4%(372/626)与41.5%(509/1227),χ^(2)=53.503,P<0.01];18~19岁新生的血压偏高检出率高于20~21岁[(51.4%(348/677)与45.3%(533/1176),χ^(2)=6.369,P<0.05)]。不同性别血压偏高组的身体形态指标均>正常血压组;大学新生收缩压与舒张压与身体形态呈现不同程度的相关性,多因素Logistics回归分析结果显示,男生的身体质量指数(body mass index,BMI)、PBF、体脂量、内脏脂肪等级(visceral fat level,VFL)、腰臀比(waist to hip ratio,WHR)和女生的体质量、BMI、体脂量、VFL超标以及女生体表面积(body surface area,BSA)下降都会增加血压偏高的风险;不同身体形态指标对血压偏高的曲线下面积(area under the curve,AUC)均>0.5,且男生的每项指标AUC均大于女生,其中男生身体形态中有多项指标与血压偏高的AUC>0.65。结论身体形态指标对男生血压偏高的诊断意义大于女生,尤其是PBF指标,全身性肥胖,特别是皮下脂肪肥胖与血压的相关性较高。

手术室护士预防医疗器械相关压力性损伤知信行现状及影响因素分析

目的探究手术室护士预防医疗器械相关压力性损伤的知信行现状,并分析其影响因素。方法采用便利抽样和整群抽样结合的方法,于2022年8至12月选取浙江省内不同地区二级及以上医院的手术室护士620名为研究对象,采用自制的手术室护士医疗器械相关压力性损伤知信行量表进行横断面调查,采用多元线性回归分析手术室护士预防器械相关压力性损伤知信行的影响因素。结果问卷有效回收率99.84%。浙江省手术室护士预防医疗器械相关压力性损伤知信行总分为(76.90±26.15)分,知识维度得分为(34.82±10.34)分,信念态度维度得分为(13.69±4.72)分,行为维度得分为(28.39±10.49)分。回归分析结果显示,医院类型、职称是手术室护士预防器械相关压力性损伤知信行水平的主要影响因素(均P<0.001)。结论浙江省手术室护士预防医疗器械相关压力性损伤知信行水平较低,主要受医院类型、职称的影响。因此,管理者需要通过多种途径为护理人员进行相关知识的培训,提高其行为能力,以降低医疗器械相关性压力性损伤的发生。

超声乳化吸除术联合房角分离术治疗PACG滤过术后眼压失控的临床疗效观察

目的探讨超声乳化吸除术(Phaco)+人工晶状体(IOL)植入联合房角分离术治疗原发性闭角型青光眼(PACG)滤过术后眼压失控的临床疗效。方法回顾性病例研究。对2020年8月至2022年5月收治的24例(25只眼)PACG滤过术后眼压失控患者,采用Phaco+IOL植入联合房角分离术治疗,比较术前、术后1 d、1周、1个月、3个月、6个月的眼压情况,术前及6个月最佳矫正视力(BCVA)、房角粘连性关闭(PAS)范围变化情况。记录术中、术后并发症情况。结果术后1 d、1周、1个月、3个月、6个月眼压、PAS范围均显著低于术前,差异具有统计学意义(均P<0.05);术后6个月视力较术前21例(22只眼)BCVA提高,3例(3只眼)BCVA无变化;术中10只眼发生前房出血,术后6只眼发生短暂性前房出血,15只眼发生前房渗出,8只眼发生角膜水肿。结论Phaco+IOL植入联合房角分离术治疗PACG滤过术后眼压失控能够有效降低眼压,提高患者视力,是安全有效的治疗方法。

手术室口诀式项目管理预防原位肝移植患者术中获得性压力性损伤的效果

目的探讨手术室口诀式项目管理预防原位肝移植患者术中获得性压力性损伤(intraoperative acquired pressure injury,IAPI)的效果。方法选取2022年1月-2023年10月于笔者所在医院行肝移植手术的64例患者为研究对象。按照入院先后顺序,将2022年1月-12月的32例患者设为对照组,将2023年1月-10月的32例患者设为观察组。对照组实施术中IAPI风险常规管理,观察组采用“一看、二定、三查、四准、五巡”的口诀式项目管理,比较2组IAPI预防措施落实情况及IAPI发生率。结果观察组IAPI预防措施落实得分高于对照组(t=6.920,P<0.001),IAPI发生率低于对照组(χ2=6.093,P=0.014)。结论手术室口诀式项目管理可以促进肝移植患者IAPI预防措施的落实,降低术中获得性压力性损伤发生率,值得临床推广应用。

高压共轨柴油机国产芯片控制系统研究

针对现有高压共轨柴油机电控单元高度依赖进口芯片、自主不足的问题,提出了基于全国产芯片的高压共轨柴油机电控单元方案。所设计的国产控制单元选用兆易创新的GD32F450芯片为控制核心,承担发动机数据采样、处理、存储与控制任务。首先,采用Boost升压电路提供喷油器峰值电流,利用分立器件设计双边驱动与电流反馈电路,在不依赖进口专用芯片的条件下,对喷油器驱动电流进行闭环控制;然后,基于FreeRTOS操作系统,开发高压共轨柴油机底层驱动软件,实现对不同任务调度周期的精准控制;最后,对所设计的电控单元进行了实验验证。结果表明,所设计的国产高压共轨柴油机电控单元功能齐全、工作稳定,双边驱动电路典型峰值电流为22 A,维持电流为10 A,最小喷射间隔时间为200μs,多次喷射性能与Bosch系统相当。发动机不同转速条件下任务调度周期精准、实时性好,研究证实了高压共轨柴油机电控单元全国产化方案的可行性,对推动发动机电控技术自主可控提供了有益参考。