Low-temperature characteristicsof rubbers and performance testsof type 120 emergencyvalve diaphragms

Purpose–The type 120 emergency valve is an essential braking component of railway freight trains,butcorresponding diaphragms consisting of natural rubber(NR)and chloroprene rubber(CR)exhibit insufficientaging resistance and low-temperature resistance,respectively.In order to develop type 120 emergency valverubber diaphragms with long-life and high-performance,low-temperatureresistant CR and NR were processed.Design/methodology/approach–The physical properties of the low-temperature-resistant CR and NRwere tested by low-temperature stretching,dynamic mechanical analysis,differential scanning calorimetryand thermogravimetric analysis.Single-valve and single-vehicle tests of type 120 emergency valves werecarried out for emergency diaphragms consisting of NR and CR.Findings–The low-temperature-resistant CR and NR exhibited excellent physical properties.The elasticityand low-temperature resistance of NR were superior to those of CR,whereas the mechanical properties of thetwo rubbers were similar in the temperature range of 0℃–150℃.The NR and CR emergency diaphragms metthe requirements of the single-valve test.In the low-temperature single-vehicle test,only the low-temperaturesensitivity test of the NR emergency diaphragm met the requirements.Originality/value–The innovation of this study is that it provides valuable data and experience for futuredevelopment of type 120 valve rubber diaphragms.

Analytical investigation of bidirectional ductile diaphragms in multi-span bridges

In the AASHTO Guide Specifications for Seismic Bridge Design Provisions,ductile diaphragms are identified as Permissible Earthquake-Resisting Elements（EREs）,designed to help resist seismic loads applied in the transverse direction of bridges.When adding longitudinal ductile diaphragms,a bidirectional ductile diaphragm system is created that can address seismic excitations acting along both the bridge’s longitudinal and transverse axes.This paper investigates bidirectional ductile diaphragms with Buckling Restrained Braces（BRBs）in straight multi-span bridge with simply supported floating spans.The flexibility of the substructures in the transverse and longitudinal direction of the bridge is considered.Design procedures for the bidirectional ductile diaphragms are first proposed.An analytical model of the example bridge with bidirectional ductile diaphragms,designed based on the proposed methodology,is then built in SAP2000.Pushover and nonlinear time history analyses are performed on the bridge model,and corresponding results are presented.The effect of changing the longitudinal stiffness of the bidirectional ductile diaphragms in the end spans connecting to the abutment is also investigated,in order to better understand the impact on the bridge’s dynamic performance.

Interest of thoracic ultrasound after cardiac surgery or interventional cardiology

Thoracic ultrasound has attracted much interest in detecting pleural effusion or pulmonary consolidation after cardiac surgery.In 2016,Trovato reported,in the World Journal of Cardiology,the interest of using,in addition to echocardiography,thoracic ultrasound.In this editorial,we highlight the value of assessing diaphragm function after cardiac surgery and interventional cardiology pro-cedures.Various factors are able to impair diaphragm function after such interventions.Diaphragm motion may be decreased by chest pain secondary to sternotomy,pleural effusion or impaired muscle function.Hemidiaphragmatic paralysis may be secondary to phrenic nerve damage complicating cardiac surgery or atrial fibrillation ablation.Diagnosis may be delayed.Indeed,respi-ratory troubles induced by diaphragm dysfunction are frequently attributed to pre-existing heart disease or pulmonary complications secondary to surgery.In addition,elevated hemidiaphragm secondary to diaphragm dysfunction is sometimes not observed on chest X-ray performed in supine position in the intensive care unit.Analysis of diaphragm function by ultrasound during the recovery period appears essential.Both hemidiaphragms can be studied by two complementary ultrasound methods.The mobility of each hemidiaphragms is measured by M-mode ultrasonography.In addition,recording the percentage of inspiratory thickening provides important information about the quality of muscle function.These two approaches make it possible to detect hemidiaphragm paralysis or dysfunction.Such a diagnosis is important because persistent diaphragm dysfunction after cardiac surgery has been shown to be associated with adverse respiratory outcome.Early respiratory physio-therapy is able to improve respiratory function through strengthening of the inspiratory muscles i.e.diaphragm and accessory inspiratory muscles.

Traumatic Diaphragmatic Hernia in Children: A Case Report

Introduction: Traumatic diaphragmatic hernia is a rare condition in children complicating closed or penetrating trauma to the abdomen and thorax. We report the case of an 11-year-old girl with a traumatic diaphragmatic hernia. Case Presentation: An 11-year-old girl was seen in the paediatric surgery department for a thoracolumbar spine deformity and intermittent chest pain. These symptoms occurred after a domestic accident involving a fall from a low wall onto the thoracolumbar spine 5 months previously. The diagnosis was suggested by the presence of a left hemithoracic hydroaera and confirmed by a thoraco-abdominal CT scan. Surgical exploration revealed a linear rupture of the entire left hemi-diaphragm with herniation of the stomach, small intestine, cecum, transverse colon and omentum. We performed a double-layer suture of the diaphragmatic rupture with a non-absorbable suture without edge rejuvenation after the reduction of the hernia. The outcome was favourable with normal postoperative radiographs at one year follow-up. Conclusion: Traumatic diaphragmatic hernia, although uncommon and difficult to diagnose, is a condition that is relatively easy to manage surgically, even if it is discovered late. In all cases of trauma to the thoracolumbar spine, regular follow-up and repeat X-rays are necessary if pain persists.

Application Effect of External Diaphragm Pacemaker Combined with Active Respiratory Circulation Technology in Pulmonary Rehabilitation of Perioperative Lung Cancer Patients

Aim: To explore the application effect of external diaphragm pacemaker combined with active respiratory circulation technology in pulmonary rehabilitation of perioperative lung cancer patients. Methods: A total of 98 lung cancer patients admitted to our hospital from April 2020 to November 2021 were selected as the observation objects, and then divided into a control group and an observation group using the random number table method, with 49 cases in each group. The control group received routine admission guidance and active respiratory circulation training, while the observation group was supplemented with external diaphragm pacemaker on the basis of the control group. The intervention effect was evaluated by blood gas indicators, pulmonary function indicators, diaphragm function indicators, sputum comfort degree, and activity tolerance indicators before and after intervention. Results: Before intervention, there were no significant differences in blood gas analysis indicators, pulmonary function indicators, diaphragm function indicators, sputum comfort degree, and activity tolerance indicators between the two groups (P > 0.05). After intervention, the improvement degree of the above indicators in the observation group was higher than that in the control group (P < 0.05). Conclusions: The application of external diaphragm pacemaker combined with active respiratory circulation technology in pulmonary rehabilitation of perioperative lung cancer patients is significant, which can effectively improve the pulmonary function, blood gas function, and diaphragm function of lung cancer patients after surgery, and improve the activities of daily living and quality of life of patients.

INVESTIGATION OF DEFORMATIONS,STRESSES AND STABILITY OF CIRCULAR CORRUGATED DIAPHRAGMS UNDER CONCENTRATED LOAD AT THE CENTER

This paper deals with the deformations, stresses and stability of circular corrugateddiaphragm under a concentrated load at the center on the basis of the large-deflection theoryof shallow shells of revolution. By using the Newton-spline method the nonlinear equationsof the shell for circular corrugated diaphragm with sine-shaped shallow waves are solved.Solutions for both unbuckled and buckled states are obtained. Numerical results are yieldedby digital computer for some circular corrugated diaphragms with a given form of corrugations.

Effects of C2 hemisection on respiratory and cardiovascular functions in rats

High ce rvical spinal co rd injuries induce permanent neuromotor and autonomic deficits.These injuries impact both central respiratory and cardiovascular functions through modulation of the sympathetic nervous system.So far,cardiovascular studies have focused on models of complete contusion or transection at the lower cervical and thoracic levels and diaphragm activity evaluations using invasive methods.The present study aimed to evaluate the impact of C2 hemisection on different parameters representing vital functions(i.e.,respiratory function,cardiovascular,and renal filtration parameters)at the moment of injury and 7 days post-injury in rats.No ventilatory parameters evaluated by plethys mography were impacted during quiet breathing after 7 days post-injury,whereas permanent diaphragm hemiplegia was observed by ultrasound and confirmed by diaphragmatic electromyography in anesthetized rats.Interestingly,the mean arterial pressure was reduced immediately after C2 hemisection,with complete compensation at 7 days post-injury.Renal filtration was unaffected at 7 days post-injury;however,remnant systolic dysfunction chara cterized by a reduced left ventricular ejection fraction persisted at 7 days post-injury.Taken together,these results demonstrated that following C2 hemisection,diaphragm activity and systolic function are impa cted up to 7 days post-injury,whereas the respiratory and cardiovascular systems display vast ada ptation to maintain ventilatory parameters and blood pressure homeostasis,with the latter likely sustained by the remaining descending sympathetic inputs spared by the initial injury.A better broad characterization of the physiopathology of high cervical spinal cord injuries covering a longer time period post-injury could be beneficial for understanding evaluations of putative therapeutics to further increase cardiorespiratory recovery.

Enhanced sampling for lipid-protein interactions during membrane dynamics

The inflexible concept of membrane curvature as an independent property of lipid structures is today obsolete.Lipid bilayers behave as many-body entities with emergent properties that depend on their interactions with the environment.In particular,proteins exert crucial actions on lipid molecules that ultimately condition the collective properties of the membranes.In this review,the potential of enhanced molecular dynamics to address cell-biology problems is discussed.The cases of membrane deformation,membrane fusion,and the fusion pore are analyzed from the perspective of the dimensionality reduction by collective variables.Coupled lipid-protein interactions as fundamental determinants of large membrane remodeling events are also commented.Finally,novel strategies merging cell biology and physics are considered as future lines of research.

隔膜泵动力端虚拟样机的计算机仿真研究与验证（英文）

采用Pro/e软件进行隔膜泵动力端-曲柄滑块机构的三维建模,利用机械系统动力学仿真软件ADAMS构建虚拟样机,通过样机仿真确定隔膜泵曲柄滑块机构的运动学和动力学参数,为隔膜泵动力端的设计打下基础。

Incremental deformation analysis of shell and corrugated diaphragm based on arbitrary configuration

With respect to an arbitrary configuration of a deformed structure, two sets of incremental equations are proposed for the deformation analysis of revolution shells and diaphragms loaded by both lateral pressures and the initial stresses produced in manufacturing. These general equations can be reduced to the simplified Koiter＇s Reissner-Meissner-Reissner （RMR） equations and the simplified Reissner＇s equations, when the initial stresses are set to zero. They can also be deduced to the total Lagrange form or the updated Lagrange form, respectively, as the structure is spec- ified as the un-deformed or the former-deformed configurations. These incremental equations can be easily transformed into finite difference forms and solved by common numerical solvers of ordinary differential equations. Some numerical examples are presented to show the applications of the incremental equations to the deep shell of revolution and the corrugated diaphragms used in microelectronical mechanical system （MEMS）. The results are in good agreement with those from finite element method （FEM）.

Laparoscopic vs computerized tomography-guided radiofrequency ablation for large hepatic hemangiomas abutting the diaphragm

AIM: To compare safety and therapeutic efficacy of laparoscopic radiofrequency(RF) ablation vs computed tomography(CT)-guided RF ablation for large hepatic hemangiomas abutting the diaphragm.METHODS: We retrospectively reviewed our sequential experience of treating 51 large hepatic hemangiomas abutting the diaphragm in 51 patients by CT-guided or laparoscopic RF ablation due to either the presence of symptoms and/or the enlargement of hemangioma.Altogether, 24 hemangiomas were ablated via a CTguided percutaneous approach(CT-guided ablation group), and 27 hemangiomas were treated via a laparoscopic approach(laparoscopic ablation group).RESULTS: The mean diameter of the 51 hemangiomas was 9.6 ± 1.8 cm(range, 6.0-12.0 cm). There was nodifference in the diameter of hemangiomas between the two groups(P > 0.05). RF ablation was performed successfully in all patients. There was no difference in ablation times between groups(P > 0.05). There were 23 thoracic complications in 17 patients: 15(62.5%, 15/24) in the CT-guided ablation group and2(7.4%, 2/27) in the laparoscopic ablation group(P< 0.05). According to the Dindo-Clavien classification,two complications(pleural effusion and diaphragmatic rupture grade Ⅲ) were major in two patients. All others were minor(grade Ⅰ). Both major complications occurred in the CT-guided ablation group. The minor complications were treated successfully with conservative measures, and the two major complications underwent treatment by chest tube drainage and thoracoscopic surgery, respectively. Complete ablation was achieved in 91.7%(22/24) and 96.3%(26/27) in the CT-guided and the laparoscopic ablation groups,respectively(P > 0.05).CONCLUSION: Laparoscopic RF ablation therapy should be used as the first-line treatment option for large hepatic hemangiomas abutting the diaphragm.It avoids thermal injury to the diaphragm and reduces thoracic complications.

Hepatic resection vs percutaneous radiofrequency ablation of hepatocellular carcinoma abutting right diaphragm

BACKGROUND It is usually difficult to adequately conduct percutaneous ultrasound-guided radiofrequency(RF) ablation for hepatocellular carcinomas(HCCs) abutting the diaphragm. Our hypothesis was that the subphrenic location of HCC could have an effect on the long-term therapeutic outcomes after hepatic resection and RF ablation.AIM To compare the long-term therapeutic outcomes of hepatic resection and percutaneous RF ablation for HCCs abutting the diaphragm.METHODS A total of 143 Child-Pugh class A patients who had undergone hepatic resection(n = 80) or percutaneous ultrasound-guided RF ablation(n = 63) for an HCC(≤ 3 cm) abutting the right diaphragm were included. Cumulative local tumor progression(LTP), cumulative intrahepatic distant recurrence(IDR), disease-free survival(DFS), and overall survival(OS) rates were estimated. Prognostic factors for DFS and OS were analyzed. Complications were evaluated.RESULTS The cumulative IDR rate, DFS rate, and OS rate for the hepatic resection group and RF ablation group at 5 years were "35.9% vs 65.8%", "64.1% vs 18.3%", and"88.4% vs 68.7%", respectively. Hepatic resection was an independent prognostic factor for DFS(P ≤ 0.001; hazard ratio, 0.352; 95%CI: 0.205, 0.605; with RF ablation as the reference category); however, treatment modality was not an independent prognostic factor for OS. The LTP rate was 46.6% at 5 years for the RF ablation group. The major complication rate was not significantly different between the groups(P = 0.630). The rate of occurrence of peritoneal seeding was higher in the RF ablation group(1.3% vs 9.5%, P = 0.044).CONCLUSION Although OS was not significantly different between patients who had gone hepatic resection or percutaneous RF ablation for HCCs abutting the diaphragm,DFS was better in the hepatic resection group.

Mechanism study of electrochemical oxidation in the terylene diaphragm cell

By using a self-made carbon/polytetrafluoroethylene （C/PTFE） O2-fed as cathode and Ti/IrO2/RuO2 as anode, the effects of electrochemical oxidation of phenol and the coal-gas wastewater containing phenol were studied. The terylene diaphragm which kept pH〉12 in cathodic compartment and pH〈1 in the anodic compartment was selected in the experiment in comparison with the other types of diaphragm. Furthermore, hydroxyl radical （HO·） was determined in the cathodic compartment of the diaphragm cell by electron spin resonance spectrum（ESR） and the fluorescence spectra. Compared with pH, the accumulated HzO2 and the COD removal of the no-diaphragm cell, the mechanism of electrochemical oxidation in the terylene diaphragm cell was supposed. The degradation of phenol was supposed to be cooperative oxidation by direct or indirect electrochemical oxidation at the anode and H2O2, HO· produced by oxygen reduction at the cathode. The mineralization of phenol in the diaphragm cell was better than that in the no-diaphragm cell. When the coal-gas wastewater was treated by the electrolysis system with terylene diaphragm, the average removal efficiency of the volatile phenol and COD were 100% and 79.6%, respectively.

Optimized functional linked neural network for predicting diaphragm wall deflection induced by braced excavations in clays

Deep excavation during the construction of underground systems can cause movement on the ground,especially in soft clay layers.At high levels,excessive ground movements can lead to severe damage to adjacent structures.In this study,finite element analyses(FEM)and the hardening small strain(HSS)model were performed to investigate the deflection of the diaphragm wall in the soft clay layer induced by braced excavations.Different geometric and mechanical properties of the wall were investigated to study the deflection behavior of the wall in soft clays.Accordingly,1090 hypothetical cases were surveyed and simulated based on the HSS model and FEM to evaluate the wall deflection behavior.The results were then used to develop an intelligent model for predicting wall deflection using the functional linked neural network(FLNN)with different functional expansions and activation functions.Although the FLNN is a novel approach to predict wall deflection;however,in order to improve the accuracy of the FLNN model in predicting wall deflection,three swarm-based optimization algorithms,such as artificial bee colony(ABC),Harris’s hawk’s optimization(HHO),and hunger games search(HGS),were hybridized to the FLNN model to generate three novel intelligent models,namely ABC-FLNN,HHO-FLNN,HGS-FLNN.The results of the hybrid models were then compared with the basic FLNN and MLP models.They revealed that FLNN is a good solution for predicting wall deflection,and the application of different functional expansions and activation functions has a significant effect on the outcome predictions of the wall deflection.It is remarkably interesting that the performance of the FLNN model was better than the MLP model with a mean absolute error(MAE)of 19.971,root-mean-squared error(RMSE)of 24.574,and determination coefficient(R^(2))of 0.878.Meanwhile,the performance of the MLP model only obtained an MAE of 20.321,RMSE of 27.091,and R^(2)of 0.851.Furthermore,the results also indicated that the proposed hybrid models,i.e.,ABC-FLNN,HHO-FLNN,HGS-FLNN,yielded more superior performances than those of the FLNN and MLP models in terms of the prediction of deflection behavior of diaphragm walls with an MAE in the range of 11.877 to 12.239,RMSE in the range of 15.821 to 16.045,and R^(2)in the range of 0.949 to 0.951.They can be used as an alternative tool to simulate diaphragm wall deflections under different conditions with a high degree of accuracy.

Numerical analysis of effect of friction between diaphragm wall and soil on braced excavation

A plane strain finite element model was established to investigate the effect of friction between diaphragm wall and soil on braced excavation. The behavior of interface between diaphragm wall and soil was simulated with the interface model of ABAQUS. Parametric studies were conducted with different diaphragm wall external friction angles δ. The results show that deflection of diaphragm wall and ground surface settlement decrease with the decrease of δ. However, the reduction effect on diaphragm wall deflection is the most significant at the depth where the maximum wall deflection occurs and can be neglected at the wall base. The ratio between wall deep inward component and wall cantilever component reaches its peak value 2.7 when δ=5°. The ratio of the maximum ground surface settlement to the maximum wall lateral deflection decreases at a reduced rate with the increase of δ. For excavation with braced diaphragm wall, the effect of friction between diaphragm and soil on the deflection of diaphragm wall and ground settlement, especially the distribution of ground surface settlement behind diaphragm, should be taken into account.

Neurally adjusted ventilator assist in very low birth weight infants:Current status

Continuous improvements in perinatal care have resultedin increased survival of premature infants.Their immature lungs are prone to injury with mechanical ventilation and this may develop into chronic lung disease(CLD) or bronchopulmonary dysplasia.Strategies to minimize the risk of lung injury have been developed and include improved antenatal management(education,regionalization,steroids,and antibiotics),exogenous surfactant administration and reduction of barotrauma by using exclusive or early noninvasive ventilatory support.The most frequently used mode of assisted ventilation is pressure support ventilation that may lead to patientventilator asynchrony that is associated with poor outcome.Ventilator-induced diaphragmatic dysfunction or disuse atrophy of diaphragm fibers may also occur.This has led to the development of new ventilation modes including neurally adjusted ventilatory assist(NAVA).This ventilation mode is controlled by electrodes embedded within a nasogastric catheter which detect the electrical diaphragmatic activity(Edi) and transmit it to trigger the ventilator in synchrony with the patient's own respiratory efforts.This permits the patient to control peak inspiratory pressure,mean airway pressure and tidal volume.Back up pressure control(PC) is provided when there is no Edi signal and no pneumatic trigger.Compared with standard conventional ventilation,NAVA improves blood gas regulation with lower peak inspiratory pressure and oxygen requirements in preterm infants.NAVA is safe mode of ventilation.The majority of studies have shown no significant adverse events in neonates ventilated with NAVA nor a difference in the rate of intraventricular hemorrhage,pneumothorax,or necrotizing enterocolitis when compared to conventional ventilation.Future large size randomized controlled trials should be established to compare NAVA with volume targeted and pressure controlled ventilation in newborns with mature respiratory drive.Most previous studies and trials were not sufficiently large and did not include longterm patient oriented outcomes.Multicenter,randomized,outcome trials are needed to determine whether NAVA is effective in avoiding intubation,facilitating extubation,decreasing time of ventilation,reducing the incidence ofCLD,decreasing length of stay,and improving long-term outcomes such as the duration of ventilation,length of hospital stay,rate of pneumothorax,CLD and other major complications of prematurity.In order to prevent barotrauma,next generations of NAVA equipment for neonatal use should enable automatic setting of ventilator parameters in the backup PC mode based on the values generated by NAVA.They should also include an upper limit to the inspiratory time as in conventional ventilation.The manufacturers of Edi catheters should produce smaller sizes available for extreme low birth weight infants.Newly developed ventilators should also include leak compensation and high frequency ventilation.A peripheral flow sensor is also essential to the proper delivery of all modes of conventional ventilation as well as NAVA.

Increased inspiratory esophagogastric junction pressure in systemic sclerosis:An add-on to antireflux barrier

AIM:To investigate crural diaphragm(CD)function in systemic sclerosis(SSc)using high-resolution manometryand standardized inspiratory maneuvers.METHODS:Eight SSc volunteers(average age,40.1years;one male)and 13 controls(average age,32.2years;six males)participated in the study.A highresolution manometry/impedance system measured the esophagus and esophagogastric junction(EGJ)pressure profile during swallows and two respiratory maneuvers:sinus arrhythmia maneuver(SAM;the average of six EGJ peak pressures during 5-s deep inhalations)and threshold maneuver(TM;the EGJ peak pressures during forced inhalation under 12 and 24 cm H2O loads).Inspiratory diaphragm lowering(IDL)was taken as the displacement of the EGJ high-pressure zone during the SAM.RESULTS:SSc patients had lower mean lower esophageal sphincter pressure than controls during normal breathing(19.7±2.8 mm Hg vs 32.2±2.7 mm Hg,P=0.007).Sinus arrhythmia maneuver pressure was higher in SSc patients than in controls(142.6±9.4 mm Hg vs 104.6±13.8 mm Hg,P=0.019).Sinus arrhythmia maneuver pressure normalized to IDL was also higher in SSc patients than in controls(83.8±13.4 mm Hg vs37.5±6.9 mm Hg,P=0.005).Threshold maneuver pressures normalized to IDL were also greater in SSc patients than in controls(TM 12 cm H2O:85.1±16.4mm Hg vs 43.9±6.3 mm Hg,P=0.039;TM 24 cm H2O:85.2±16.4 mm Hg vs 46.2±6.6 mm Hg,P=0.065).Inspiratory diaphragm lowering in SSc patients was less than in controls(2.1±0.3 cm vs 3±0.2 cm,P=0.011).CONCLUSION:SSc patients had increased inspiratory EGJ pressure.This is an add-on to EGJ pressure and indicates that the antireflux barrier can be trained.

Dispersion of the Mechanical Parts Performance Indicators Based on the Concept of Random Vector

To solve the precision and reliability problem of various machinery equipments and military vehicles, some military organisations, the industrial sector and the academia at home and abroad begin to pay attention to the statistical distribution of machining dimensions, material properties and service loads, and the system reliability optimization design with constraints and reliability optimization design of various mechanical parts is studied in this way. However, the above researches focus on solving the strength and the life problem, and no studies have been done on the discrete degree and discrete pattern of other performance indicators. The concept of using a random vector to describe the mechanical parts performance indicators is presented; characteristics between the value of the vector variance matrix determinant and the sum of the diagonal covariance matrix in describing the performance indicators of vector dispersion are studied and compared. A clutch diaphragm spring is set as an example, the geometric dimension indicator is described with random vector, and the applicability of using variance matrix determinant and variance matrix trace of geometric dimension vector to describe discrete degree of random vector is studied by using Monte-Carlo simulation method and component discrete degree perturbation method. Also, the effects of different components of diaphragm spring geometric dimension vector on the value of covariance matrix determinant and the sum of covariance matrix diagonal of diaphragm spring performance indicators vector are analyzed. The present study shows that the impacts of the dispersion of diaphragm spring cone angle on every performance dispersion are all ranked first, and far exceed that of other dimension dispersion. So it must be strictly controlled in the production process. The result of the research work provides a reference for the design of diaphragm spring, and also it presents a proper method for researching the performance of other mechanical parts.

NONLINEAR BENDING OF CORRUGATED DIAPHRAGM WITH LARGE BOUNDARY CORRUGATION UNDER COMPOUND LOAD

By using the simplified Reissner's equation of axisymmetric shells of revolution, the nonlinear bending of a corrugated annular plate with a large boundary corrugation and a nondeformable rigid body at the center under compound load are investigated. The nonlinear boundary value problem of the corrugated diaphragm reduces to the nonlinear integral equations by applying the method of Green's function. To solve the integral equations, a so_called interpolated parameter important to prevent divergence is introduced into the iterative format. Computation shows that when loads are small, any value of interpolated parameter can assure the convergence of iteration. Interpolated parameter equal or almost equal to 1 yields a faster convergence rate; when loads are large, interpolated parameter cannot be taken too large in order to assure convergence. The characteristic curves of the corrugated diaphragm for different load combinations are given. The obtained characteristic curves are available for reference to design. It can be concluded that the deflection is larger when the diaphragm is acted by both uniform load and concentrated load than when it is acted only by uniform load. The solution method can be applied to corrugated shells of arbitrary diametral sections.

Mechanisms of change contraction of function of the muscles <i>in vitro</i>at allergic

In this work, mechanisms of influence of protein sensibility of an organism on contractile function of the isolated skeletal muscles of the mouse—“fast”—musculus extensor digitorum longus, “mixed”—musculus diaphragma and “slow”— musculus soleus are investigated. It is shown that at a protein sensitization all “fast”, “mixed” and “slow” skeletal muscles change the contractile properties. The vector of these changes for muscles with a various phenotypes carries opposite character. Force of the reduction caused carbacholine at a “slow” and “mixed” muscles increase, at “fast”—decreases. A vector of change of force of reduction on carbacholine at protein sensitization at these skeletal muscles correlates with changes of non-quantum secretion acetylcholine in a zone of a trailer plate. Opposite changes of functional properties of “fast” and “mixed” muscles and “slow” muscles of a shin of the mouse at protein sensitization are caused by dynamics cholinoceptive processes of excitation of membrane muscular fibers. It comes out with the assumption, that change of the contraction functions of skeletal muscles at protein sensitization is caused by changes of cholinoceptive processes of excitation of a membrane of muscular fibers, and other changes in system of electro-mechanical interface.