STABILITY OF TRANSONIC SHOCKS TO THE EULER-POISSON SYSTEM WITH VARYING BACKGROUND CHARGES

This paper is devoted to studying the stability of transonic shock solutions to the Euler-Poisson system in a one-dimensional nozzle of finite length.The background charge in the Poisson equation is a piecewise constant function.The structural stability of the steady transonic shock solution is obtained by the monotonicity argument.Furthermore,this transonic shock is proved to be dynamically and exponentially stable with respect to small perturbations of the initial data.One of the crucial ingredients of the analysis is to establish the global well-posedness of a free boundary problem for a quasilinear second order equation with nonlinear boundary conditions.

Investigation of system parameters towards safer impact based shock-to-detonation transition in a novel laser driven flyer plate prototype

Laser driven flyer plate technology offers improved safety and reliability for detonation of explosives in industrial applications ranging from mining and stone quarrying to the aerospace and defense industries.This study is based on developing a safer laser driven flyer plate prototype comprised of a laser initiator and a flyer plate subsystem that can be used with secondary explosives.System parameters were optimized to initiate the shock-to-detonation transition(SDT)of a secondary explosive based on the impact created by the flyer plate on the explosive surface.Rupture of the flyer was investigated at the mechanically weakened region located on the interface of these subsystems,where the product gases from the deflagration of the explosive provide the required energy.A bilayer energetic material was used,where the first layer consisted of a pyrotechnic component,zirconium potassium perchlorate(ZPP),for sustaining the ignition by the laser beam and the second layer consisted of an insensitive explosive,cyclotetramethylene-tetranitramine(HMX),for deflagration.A plexiglass interface was used to enfold the energetic material.The focal length of the laser beam from the diode was optimized to provide a homogeneous beam profile with maximum power at the surface of the ZPP.Closed bomb experiments were conducted in an internal volume of 10 cm^(3) for evaluation of performance.Dependency of the laser driven flyer plate system output on confinement,explosive density,and laser beam power were analyzed.Measurements using a high-speed camera resulted in a flyer velocity of 670±20 m/s that renders the prototype suitable as a laser detonator in applications,where controlled employment of explosives is critical.

Systematic review with expert consensus on use of extracorporeal hemoadsorption in septic shock:An Indian perspective

BACKGROUND Septic shock is a severe form of sepsis characterised by deterioration in circulatory and cellular-metabolic parameters.Despite standard therapy,the outcomes are poor.Newer adjuvant therapy,such as CytoSorb®extracorporeal haemoadsorption device,has been investigated and shown promising outcome.However,there is a lack of some guidance to make clinical decisions on the use of CytoSorb®haemoadsorption as an adjuvant therapy in septic shock in Indian Setting.Therefore,this expert consensus was formulated.AIM To formulate/establish specific consensus statements on the use of CytoSorb®haemoadsorption treatment based on the best available evidence and contextualised to the Indian scenario.METHODS We performed a comprehensive literature on CytoSorb®haemoadsorption in sepsis,septic shock in PubMed selecting papers published between January 2011 and March 20232021 in English language.The statements for a consensus document were developed based on the summarised literature analysis and identification of knowledge gaps.Using a modified Delphi approach combining evidence appraisal and expert opinion,the following topics related to CytoSorb®in septic shock were addressed:need for adjuvant therapy,initiation timeline,need for Interleukin-6 levels,duration of therapy,change of adsorbers,safety,prerequisite condition,efficacy endpoints and management flowchart.Eleven expert members from critical care,emergency medicine,and the intensive care participated and voted on nine statements and one open-ended question.RESULTS Eleven expert members from critical care,emergency medicine,and the intensive care participated and voted on nine statements and one open-ended question.All 11 experts in the consensus group(100%)participated in the first,second and third round of voting.After three iterative voting rounds and adapting two statements,consensus was achieved on nine statements out of nine statements.The consensus expert panel also recognised the necessity to form an association or society that can keep a registry regarding the use of CytoSorb®for all indications in the open-ended question(Q10)focusing on“future recommendations for CytoSorb®therapy”.CONCLUSION This Indian perspective consensus statement supports and provides guidance on the use of CytoSorb®haemoadsorption as an adjuvant treatment in patients with septic shock to achieve optimal outcomes.

Efficacy and safety of ulinastatin in the treatment of septic shock:a systematic review and meta-analysis

Background:Septic shock is a common systemic inflammatory response syndrome for critical patients in the intensive care unit.Ulinastatin is currently used for the treatment of septic shock.Our study sought to evaluate the efficacy and safety of ulinastatin in the treatment of septic shock patients.Methods:Three English databases(Embase,Medline,and Cochrane Library)and four Chinese databases(China National Knowledge Infrastructure,Wanfang data,SinoMed,and VIP)were searched for published randomized controlled trials.Stata 16.0 software was used to conduct the meta-analysis.Results:A total of 48 articles were included(Chinese article 47,1 in English).The results show that the treatment of ulinastatin could reduce mortality(risk ratio=0.63,95%confidence interval(CI)(0.55,0.72)),multiple organ dysfunction syndrome(risk ratio=0.6,95%CI(0.53,0.68)),length of intensive care unit stay(mean difference(MD)=-3.92,95%CI(-4.65,-3.18)),length of hospital stay(MD=-4.39,95%CI(-6.63,-2.15))and decrease Acute Physiology and Chronic Health Evaluation II score(MD=-4.55,95%CI(-5.63,-3.47))and Sequential Organ Failure Assessment score(MD=-2.02,95%CI(-2.59,-1.44))with P<0.001.Moreover,it lowers TNF-α(standardized mean difference(SMD)=-1.78,95%CI(-2.24,-1.32)),Interleukin-6(SMD=-1.17,95%CI(-1.55,-0.8)),C reactive protein(SMD=-1.49,95%CI(-1.99,-0.99)),hypersensitive C-reactive protein(SMD=-1.9,95%CI(-2.87,-0.94))and procalcitonin(SMD=-0.89,95%CI(-1.12,-0.67))levels in the body.Conclusions:Available evidence shows that ulinastatin reduces case mortality rate,multiple organ dysfunction syndrome,length of intensive care unit stay,and length of hospital stay and decreases Acute Physiology and Chronic Health Evaluation II score and Sequential Organ Failure Assessment score.Moreover,it also lowers TNF-α,Interleukin-6,C reactive protein,hypersensitive C-reactive protein,and procalcitonin levels in the body.

Effectiveness of Combined Application of Shock Index and Early Warning Scoring System in Patients with Acute Gastrointestinal Hemorrhage

Objective:To explore the effect of the combined application of the Shock Index(SI)and the Early Warning Score(EWS)in patients with acute gastrointestinal bleeding.Methods:Seventy patients with acute gastrointestinal bleeding admitted to a hospital from June 2022 to May 2024 were selected and randomly divided into two groups:the control group and the observation group,with 35 patients in each group.The control group received conventional emergency care measures,while the observation group received SI combined with NEWS emergency care measures.The treatment effects in both groups were compared.Results:The observation group had shorter waiting times for consultation(4.45±1.59 minutes),intravenous access establishment(6.79±2.52 minutes),hemostasis time(4.41±1.52 hours),and hospital stays(8.39±2.13 days)compared to the control group,which had times of 5.46±1.34 minutes,8.41±2.16 minutes,5.16±1.47 hours,and 10.26±2.98 days,respectively.The differences were statistically significant(P<0.05).Before management,there were no significant differences in the levels of hemoglobin,prealbumin,and serum protein between the two groups(P>0.05).However,after systematic emergency management,the serum indexes in both groups significantly improved,with the observation group showing greater improvement than the control group,and these differences were statistically significant(P<0.05).In the observation group,only one case of cardiovascular complications occurred during the rescue period,with an incidence rate of 2.86%.In contrast,the control group experienced eight cases of complications,including hemorrhagic shock,anemia,multi-organ failure,cardiovascular complications,and gastrointestinal rebleeding,with an incidence rate of 22.85%.The difference between the groups was statistically significant(P<0.05).Conclusion:The application of SI combined with EWS emergency care measures in patients with acute gastrointestinal hemorrhage can effectively improve serum indexes,shorten resuscitation time and hospital stay,and reduce the risk of complications such as hemorrhagic shock,anemia,infection,multi-organ failure,cardiovascular complications,acute renal failure,and gastrointestinal rebleeding.This approach has positive clinical application value.

Prognostic impact of hypernatremia for septic shock patients in the intensive care unit

BACKGROUND Hypernatremia represents a significant electrolyte imbalance associated with numerous adverse outcomes,particularly in cases of intensive care unit(ICU)-acquired hypernatremia(IAH).Nevertheless,its relevance in patients with septic shock remains uncertain.AIM To identify independent risk factors and their predictive efficacy for IAH to improve outcomes in patients with septic shock.METHODS In the present retrospective single-center study,a cohort of 157 septic shock patients with concurrent hypernatremia in the ICU at The First Affiliated Hospital of Soochow University,between August 1,2018,and May 31,2023,were analyzed.Patients were categorized based on the timing of hypernatremia occurrence into the IAH group(n=62),the non-IAH group(n=41),and the normonatremia group(n=54).RESULTS In the present study,there was a significant association between the high serum sodium concentrations,excessive persistent inflammation,immunosuppression and catabolism syndrome and chronic critical illness,while rapid recovery had an apparent association with normonatremia.Moreover,multivariable analyses revealed the following independent risk factors for IAH:Total urinary output over the preceding three days[odds ratio(OR)=1.09;95%CI:1.02–1.17;P=0.014],enteral nutrition(EN)sodium content of 500 mg(OR=2.93;95%CI:1.13–7.60;P=0.027),and EN sodium content of 670 mg(OR=6.19;95%CI:1.75–21.98;P=0.005)were positively correlated with the development of IAH.Notably,the area under the curve for total urinary output over the preceding three days was 0.800(95%CI:0.678–0.922,P=0.001).Furthermore,maximum serum sodium levels,the duration of hypernatremia,and varying sodium correction rates were significantly associated with 28-day in-hospital mortality in septic shock patients(P<0.05).CONCLUSION The present findings illustrate that elevated serum sodium level was significantly associated with a poor prognosis in septic shock patients in the ICU.It is highly recommended that hypernatremia be considered a potentially important prognostic indicator for the outcome of septic shock.

Influence of laser shock peening on microstructure and high-temperature oxidation resistance of Ti45Al8Nb alloy fabricated via laser melting deposition

Laser shock peening(LSP)was used to enhance the high-temperature oxidation resistance of laser melting deposited Ti45Al8Nb alloy.The microstructure and high-temperature oxidation behavior of the as-deposited Ti45Al8Nb alloy before and after LSP were investigated by scanning electron microscopy,X-ray diffraction,and electron backscatter diffraction.The results indicated that the rate of mass gain in the as-deposited sample after LSP exhibited a decrease when exposed to an oxidation temperature of 900℃,implying that LSP-treated samples exhibited superior oxidation resistance at high temperatures.A gradient structure with a fine-grain layer,a deformed-grain layer,and a coarse-grain layer was formed in the LSP-treated sample,which facilitated the diffusion of the Al atom during oxidation,leading to the formation of a dense Al_(2)O_(3)layer on the surface.The mechanism of improvement in the oxidation resistance of the as-deposited Ti45Al8Nb alloy via LSP was discussed.

Septic shock due to cytomegalovirus colitis associated with rituximab use:A case report

BACKGROUND Cytomegalovirus(CMV)infections can cause significant morbidity and mortality in immunocompromised individuals.CMV targets dysfunctional lymphocytes.Chronic rituximab(RTX)therapy can cause B-lymphocyte dysfunction,increasing CMV risk.Rarely,CMV infections present with critical illness such as septic shock.CASE SUMMARY A 64-year-old African American woman presented with generalized weakness and non-bloody watery diarrhea of 4-6 weeks duration.She did not have nausea,vomiting or,abdominal pain.She had been on monthly RTX infusions for neuromyelitis optica.She was admitted for septic shock due to pancolitis.Blood investigations suggested pancytopenia and serology detected significantly elevated CMV DNA.Valganciclovir treatment led to disease resolution.CONCLUSION This case illustrates an extremely rare case of CMV colitis associated with RTX use presenting with septic shock.High suspicion for rare opportunistic infections is imperative in individuals with long-term RTX use.

Cardiovascular involvement in multisystem inflammatory syndrome in children and midterm follow-up from a pediatric tertiary center in India

BACKGROUND In multisystem inflammatory syndrome in children(MIS-C)with coronavirus disease 2019,there was paucity of data from low-income and middle-income countries on cardiovascular involvement and its longitudinal outcomes.We planned to estimate the pattern of cardiovascular involvement among children with MIS-C and its mid-term outcomes.AIM To determine association between cardiovascular abnormalities and clinical and laboratory parameters.To study the time-line for resolution of various abnormalities.METHODS In this prospective study done in a tertiary care hospital,270 were recruited from June 2020 to January 2022.Baseline demographic data and clinical presentation were recorded.Laboratory parameters and echocardiography were done at admission.Follow-up was done at 2 weeks,3 months,6 months and 1 year after diagnosis.Descriptive statistics were used for parametric and non-parametric data.Risk factors were identified by multivariate regression analysis.RESULTS The 211(78.2%)had cardiac involvement and 102 needed intensive care unit(ICU)admission.Cardiovascular abnormalities observed were shock 123(45.6%),coronary dilatation 28(10.4%),coronary aneurysm 77(28.5%),left ventricular(LV)dysfunction 78(29.3%),mitral regurgitation(MR)77(28.5%)and pericardial effusion 98(36.3%).Coronary artery aneurysm/dilatation during follow-up at 2 weeks and 1 year were 25.7%and 0.9%respectively.Multivariate regression analysis revealed breathlessness[odds ratio(OR)=3.91,95%CI:1.25-12.21,P=0.019]and hi-flow nasal cannula(HFNC)support(OR=8.5,95%CI:1.06-68.38,P=0.044)as predictors of cardiovascular involvement.Higher mean age(OR=1.16,95%CI:1.02-1.32,P=0.026),breathlessness(OR=4.99,95%CI:2.05-12.20,P<0.001),gallop(OR=4.45,95%CI:0.41-2.52,P=0.016),MR(OR=3.61,95%CI:1.53-8.53,P=0.004)and invasive ventilation(OR=4.01,95%CI:1.28-12.58,P=0.017)were predictive of LV dysfunction.Altered sensorium(OR=4.96,95%CI:2.23-11.02,P<0.001),headache(OR=6.61,95%CI:1.46-29.92,P=0.014),HFNC(OR=7.03,95%CI:2.04-24.29,P=0.002),non-rebreathing mask usage(OR=21.13,95%CI:9.00-49.61,P<0.001)and invasive ventilation(OR=5.64,95%CI:1.42-22.45,P=0.014)were risk factors for shock.Anemia was a risk factor for coronary involvement(OR=3.09,95%CI:1.79-5.34,P<0.001).CONCLUSION Significant number of children with MIS-C had cardiovascular involvement contributing to higher ICU management.Although shock resolved quickly,resolution of ventricular function and coronary abnormalities were slower,and hence warrants a structured long-term follow-up protocol.

Experimental and numerical simulation of the attenuation effect of blast shock waves in tunnels at different altitudes

Traffic engineering such as tunnels in various altitudinal gradient zone are at risk of accidental explosion,which can damage personnel and equipment.Accurate prediction of the distribution pattern of explosive loads and shock wave propagation process in semi-enclosed structures at various altitude environment is key research focus in the fields of explosion shock and fluid dynamics.The effect of altitude on the propagation of shock waves in tunnels was investigated by conducting explosion test and numerical simulation.Based on the experimental and numerical simulation results,a prediction model for the attenuation of the peak overpressure of tunnel shock waves at different altitudes was established.The results showed that the peak overpressure decreased at the same measurement points in the tunnel entrance under the high altitude condition.In contrast,an increase in altitude accelerated the propagation speed of the shock wave in the tunnel.The average error between the peak shock wave overpressure obtained using the overpressure prediction formula and the measured test data was less than15%,the average error between the propagation velocity of shock waves predicted values and the test data is less than 10%.The method can effectively predict the overpressure attenuation of blast wave in tunnel at various altitudes.

Role of variation coefficient of stone density in determining success of shock wave lithotripsy in urinary calculi

BACKGROUND Various stone factors can affect the net results of shock wave lithotripsy(SWL).Recently a new factor called variation coefficient of stone density(VCSD)is being considered to have an impact on stone free rates.AIM To assess the role of VCSD in determining success of SWL in urinary calculi.METHODS Charts review was utilized for collection of data variables.The patients were subjected to SWL,using an electromagnetic lithotripter.Mean stone density(MSD),stone heterogeneity index(SHI),and VCSD were calculated by generating regions of interest on computed tomography(CT)images.Role of these factors were determined by applying the relevant statistical tests for continuous and categorical variables and a P value of<0.05 was gauged to be statistically significant.RESULTS There were a total of 407 patients included in the analysis.The mean age of the subjects in this study was 38.89±14.61 years.In total,165 out of the 407 patients could not achieve stone free status.The successful group had a significantly lower stone volume as compared to the unsuccessful group(P<0.0001).Skin to stone distance was not dissimilar among the two groups(P=0.47).MSD was significantly lower in the successful group(P<0.0001).SHI and VCSD were both significantly higher in the successful group(P<0.0001).CONCLUSION VCSD,a useful CT based parameter,can be utilized to gauge stone fragility and hence the prediction of SWL outcomes.

Design of handheld terminal for shock wave pressure measurement system

Considering that it is difficult to monitor the measurement system and amend the test parameters on the scene in shock wave overpressure measurement and it is inconvenient to operate and carry traditional PC in outdoor experiments, a new handheld terminal for shock wave pressure measurement system based on ARM is designed, The handheld terminal, whose ap- plication program is developed by the software of Qt, can control the measurement system by Wi-Fi and perform the functions of monitoring the system state, transmitting the data by wireless and displaying waveforms. To prevent data loss, USB inter- face is designed to read the data The test results show that the designed handheld terminal has good stability and reliability in several explosion experiments.

H pylori infection and systemic antibodies to CagA and heat shock protein 60 in patients with coronary heart disease

AIM: To determine the overall prevalence of H pylori and CagA positive H pylori infection and the prevalence of other bacterial and viral causes of chronic infection in patients with coronary heart disease (CHD), and the potential role of anti-heat-shock protein 60 (Hsp60) anti- body response to these proteins in increasing the risk of CHD development. METHODS: Eighty patients with CHD and 160 controls were employed. We also compared the levels of anti- heat-shock protein 60 (Hsp60) antibodies in the two groups. The H pylori infection and the CagA status were determined serologically, using commercially available enzyme-linked immunosorbent assays (ELISA), and a Western blotting method developed in our laboratory. Systemic antibodies to Hsp60 were determined by a sandwich ELISA, using a polyclonal antibody to Hsp60 to sensitise polystyrene plates and a commercially available human Hsp60 as an antigen. RESULTS: The overall prevalence of H pylori infec- tion was 78.7% (n = 63) in patients and 76.2% (n = 122) in controls (P = 0.07). Patients infected by CagA- positive (CagA+) H pylori strains were 71.4% (n = 45) vs 52.4% of infected controls (P = 0.030, OR = 2.27). Sys-temic levels of IgG to Hsp60 were increased in H pylori- negative patients compared with uninfected controls (P < 0.001) and CagA-positive infected patients compared with CagA-positive infected controls (P = 0.007). CONCLUSION: CagA positive H pylori infection may concur to the development of CHD; high levels of anti- Hsp60 antibodies may constitute a marker and/or a con- comitant pathogenic factor of the disease.

Application of pulse index continuous cardiac output system in elderly patients with acute myocardial infarction complicated by cardiogenic shock: A prospective randomized study

BACKGROUND Cardiogenic shock (CS) secondary to acute myocardial infarction (AMI) complicates management of the condition, and often leads to poor prognosis. Prompt and accurate monitoring of cardiovascular and accompanying hemodynamic changes is crucial in achieving adequate management of the condition. Advances in technology has availed procedures such as pulse index continuous cardiac output (PiCCO), which can offer precise monitoring of cardiovascular functions and hemodynamic parameters. In this study, PiCCO is evaluated for its potential utility in improving management and clinical outcomes among elderly patients with AMI complicated by CS. AIM To assess whether use of the PiCCO system can improve clinical outcomes in elderly patients with AMI complicated by CS.METHODS Patients from emergency intensive care units (EICU) or coronary care units (CCU) were randomized to receive PiCCO monitoring or not. The APACHE II score, SOFA score, hs-TnI, NT-proBNP, PaO2/FiO2 ratio and lactate levels on day 1, 3 and 7 after treatment were compared. The infusion and urine volume at 0-24 h, 24-48 h and 48-72 h were recorded, as were the cardiac index (CI), extravascular lung water index (EVLWI), intrathoracic blood volume index (ITBVI) and global end diastolic volume index (GEDVI) at similar time intervals. RESULTS Sixty patients with AMI complicated by CS were included in the study. The PiCCO group had a significantly lower APACHE II score, SOFA score, hs-TnI and NT-proBNP levels on day 1, 3 and 7 after treatment. The infusion and urine volume during 0-24 h in the PiCCO group were significantly greater, and this group also showed significantly higher ADL scores. Furthermore, the PiCCO group spent lesser days on vasoactive agents, mechanical ventilation, and had a reduced length of stay in EICU/CCU. Additionally, the CI was significantly higher at 48 h and 72 h in the PiCCO group compared with that at 24 h, and the EVLWI, ITBVI and GEDVI were significantly decreased at 48 h and 72 h. CONCLUSION Applying the PiCCO system could improve the clinical outcomes of elderly patients with AMI complicated by CS.

A High-Spectral-Resolution Laser Raman System and Its Application in Shock–Compressed Benzene

Raman measurements play an important role in examining the molecular changes associated with shock-induced structural and chemical changes in condensed materials.We combine a high spectra-resolution Raman system with a two-stage light gas gun to provide better quality data than the transient Raman system used previously.Representative measurements are presented for the shock compression of benzene.The high spectral resolution data have provided an insight into molecular changes that could not be obtained from time-resolved methods.

Clinical application of plasma shock wave lithotripsy in treating impacted stones in the bile duct system

AIM： To verify the safety and efficacy of plasma shock wave lithotripsy （PSWL） in fragmenting impacted stones in the bile duct system. METHODS： From September 1988 to April 2005, 67 patients （26 men and 41 women） with impacted stones underwent various biliary operations with tube （or T-tube） drainage. Remnant and impacted stones in the bile duct system found by cholangiography after the operation were fragmented by PSWL and choledochofiberscopy. A total of 201 impacted stones were fragmented by PSWL setting the voltage at 2.5-3.5 kV, and the energy output at 2-3.1 for each pulse of PSWL. Then the fragmented stones were extracted by choledochofiberscopy. The safety and efficacy of PSWL were observed during and after the procedure. RESULTS： One hundred and ninety-nine of 201 impacted stones （99.0%） in the bile duct system were successfully fragmented using PSWL and extracted by choledochofiberscopy. The stone clearance rate for patients was 97% （65/67）. Ten patients felt mild pain in the right upper quadrant of the abdomen, and could tolerate it well. Eleven patients had a small amount of bleeding from the mucosa of the bile duct. The bleeding was transient and stopped spontaneously within 2 min of normal saline irrigation. There were no significant complications during and after the procedure. CONCLUSION：PSWL is a safe and effective method for fragmenting impacted stones in the bile duct system.

Reliability Comparison Between Parallel and Cold-standby Two-unit System Under Poisson Shock

This paper investigates the comparison problem of the reliability index between a parallel and a cold-standby system,both of which are consisting of two identical units.On the contrary to the general intuitive result,we proved that,under the condition that the system is shocked by a Poisson stream,the life time of the parallel system is longer than that of the cold-standby one in the sense of probability.

THE SHOCK WAVES FOR A MIXED-TYPE SYSTEM FROM CHEMOTAXIS

In this paper,we study the shock waves for a mixed-type system from chemotaxis.We are concerned with the jump conditions for the left state which is located in the elliptical region and the right state in the hyperbolic region.Under the generalized entropy conditions,we find that there are different shock wave structures for different parameters.To guarantee the uniqueness of the solutions,we obtain the admissible shock waves which satisfy the generalized entropy condition in both parameters.Finally,we construct the Riemann solutions in some solvable regions.

TRANSONIC SHOCK SOLUTIONS TO THE EULER SYSTEM IN DIVERGENT-CONVERGENT NOZZLES

In this paper,we study the transonic shock solutions to the steady Euler system in a quasi-one-dimensional divergent-convergent nozzle.For a given physical supersonic inflow at the entrance,we obtain exactly two non-isentropic transonic shock solutions for the exit pressure lying in a suitable range.In addition,we establish the monotonicity between the location of the transonic shock and the pressure downstream.

Effect of osmotic shock on the redox system in plasma membrane of Dunaliella salina

The unicellular halotolerant alga Dunaliella salina had the ability to oxidize NADH and reduce Fe(CN)63-. The redox reactions were to some extent stimulated by slight hyperosmotic shock (2.0 mol/L → 2.6 mol/L NaCl), butmarkably inhibited by abrupt hyperosmotic shock (2.0mol/L → 3.5 mol/L NaCl) and hypoosmotic shock (2.0mol/L → 1.0 mol/L NaCl; 2.0 mol/L→0.67 mol/L NaCl).With the adaptation of algal cells to osmotic shock by accumulating or degrading intracellular glycerol, the plasmalemma redox activities were also restored. The O2 uptake stimulated by NADH could be promoted by FA and SHAM. Hypoosmotic shock increases the basal respiration rate of alga cells, but weakened the stimulating effects of NADH, FA and SHAM on O2 uptake. On the other hand, hyperosmotic shock reduced the basal respiration rate, but relatively enhanced the above effects of NADH, FA and SHAM. H+ extrusion of alga cells was inhibited by NADH and stimulated by Fe(CN)63- Vanadate and DES could inhibit H+ efflux, but had little effect in the presence of NADH and Fe(CN)63-. Both hyperand hypoosmotic shock stimulated H+ extrusion. This effect could be totally inhibited by vanadate and DES, but almost unaffected by 8-hydroxyquinoline. It was suggested that H+-ATPase probably played a more important role in H+ extrusion and osmoregulation under the conditions of osmotic shock.