Intermittent Conditions Research Articles

Soil Compaction Induced Changes in Morpho-physiological Characteristics of Common Bean

The progress in identification of genotypes with roots showing greater ability to penetrate compacted soils under moisture stress and understanding the physiological basis and morphological expression of the characteristics associated is fundamental to improving crop’s tolerance to drought and to increase productivity under individual and combined stress conditions. Our objectives were to: (i) determine genotypic differences in root penetration ability of common bean (Phaseolus vulgaris L.) using two methods (compacted soil layers and wax-petrolatum layers) to simulate soil compaction; and (ii) identify the morpho-physiological characteristics associated with the ability to penetrate compacted layers under well-watered and intermittent drought conditions in a greenhouse environment. Six common bean genotypes of different origin (Andean, Mesoamerican and interspecific) were tested in two trials. In the first trial, we evaluated genotypic differences in morpho-physiological characteristics that were associated with the root’s ability to penetrate compacted soil layers of 1.2, 1.4, and 1.6 g cm−3 bulk densities. In the second trial, we used another method to determine genotypic differences in root’s ability to penetrate wax-petrolatum layers of low, medium, and high mechanical impedance. The conditions for root growth were severely restricted by compaction and aggravated by drought stress. The medium level of mechanical impedance of wax petrolatum layer method showed the best results to evaluate bean genotypes for soil compaction tolerance. Among the six genotypes tested, ALB 91 (an interspecific line) was identified as the one with the greatest root penetration ability compared with A774 which showed the lowest root penetration ability under both well-watered and drought conditions.

Stochastic Algorithms for Controller Optimization of Grid Tied Hybrid AC/DC Microgrid with Multiple Renewable Sources

—The hybrid AC/DC microgrid (MG) configuration is efficient as it reduces the need for multiple power conversions and hence losses. Therefore, this paper focuses on the study of grid assisted hybrid AC/DC MG comprising of solar PV and fuel cell (FC) systems on DC subgrid with supercapacitor (SC) as the short term storage device and wind energy conversion system (WECS) on the AC subgrid. A comprehensive study of the operation of MG is performed under varying system conditions in MATLAB/Simulink software. The real and reactive power (PQ) control scheme is used to regulate the DC bus voltage and power flow between the subgrids. Genetic algorithm (GA), artificial bee colony (ABC) optimization, particle swarm optimization (PSO) and the PSO with new update mechanism (PSOd) are used to compute the optimum gain values of proportional-integral (PI) controller in the PQ control scheme. The SC bank effectively reduces the power stress on the subgrids of the proposed hybrid MG system during intermittent conditions of load and generation. In addition, a comparative study of the heuristic optimization techniques is presented in detail. The ABC algorithm is found to arrive at the best results in determining the optimal gains of PI controller

Heat storage and release characteristics of composite phase change wall under different intermittent heating conditions

During intermittent heating, the heat storage and release of building envelopes are caused by indoor thermal environment variations. The heat storage and release process of the building envelope inside can be used to reduce heat loss in intermittent cycles and maintain the indoor thermal environment for occupant comfort while saving energy by efficiency in the operation. In this research, the building envelope was integrated with phase change materials, and the heat transfer model was established and verified to analyze the heat storage and release processes of composite phase change wall (composite-PCW) under two typical intermittent heating conditions. Effective heat storage utilization rate η and heat loss rate ε were used to evaluate the wall’s heat storage and release characteristics and energy efficiency, and the composite-PCW was compared with a solid brick wall. The results show that (1) the η of the composite-PCW was 75.07% in the long intermittent condition; (2) the thermal processes were relatively stable in the last three cycles of the short intermittent condition, and the η was greater than 70%; and (3) the ε of the composite-PCW was smaller under the two intermittent conditions compared with the solid brick wall and was reduced by more than 36%.

Advances in Water Distribution Networks

This Editorial presents a representative collection of 10 papers, presented in the Special Issue on Advances in Water Distribution Networks (WDNs), and frames them in the current research trends. Four topics are mainly explored: simulation and optimization modelling, topology and partitioning, water quality, and service effectiveness. As for the first topic, the following aspects are dealt with: pressure-driven formulations, algorithms for the optimal location of control valves to minimize leakage, benefits of water discharge prediction for the remote real time control (RTC) of valves, and transients generated by pumps operating as turbines (PATs). In the context of the second topic, a topological taxonomy of WDNs is presented, and partitioning methods for the creation of district metered areas (DMAs) are compared. With regards to the third topic, the vulnerability to trihalomethane is assessed, and a statistical optimization model is presented to minimise heavy metal releases. Finally, the fourth topic focusses on estimation of non-revenue water (NRW), inclusive of leakage and unauthorized consumption, and on assessment of service under intermittent supply conditions.

Intermittent conditioning of library archives: Microclimate analysis and energy impact

Libraries and archives house a majority of cultural heritage objects. The main purpose of libraries and archives is to provide suitable indoor climate conditions for preservation of their collection. In general, a large bulk of hygroscopic material is present which aids stable indoor climate conditions. Limited disturbances due to visitor presence occur in repositories and excludes to a large extent thermal comfort requirements. Library archives show potential of more tolerant setpoint control with permissible fluctuations. Little research is present into dynamic setpoint control and intermittent conditioning in libraries and archives. The aim of this study is to explore the possibility for intermittent conditioning and dynamic setpoint control on the energy impact and microclimate behavior in a library case study in The Netherlands. By means of a hygrothermal monitoring campaign from August 2016 to August 2017 the current indoor climate has been assessed under regular conditions and intervention periods (summer and winter) where the air handling unit was turned off. Both temporal and spatial measurements provided important information on microclimate behavior of the investigated repositories. A validated multi-zone model was used to investigate multiple setpoint strategies. Results show the potential of intermittent conditioning depending on whether dynamic setpoint conditions are used during operational hours (e.g. ASHRAE climate classes). If static conditions are applied, energy demand increases significantly, however, under dynamic setpoint control significant energy savings are possible. The lifetime multiplier is used to assess the chemical risks. The majority of investigated setpoint strategies show increased chemical risk.

PO-075 Effects of hypoxic exercise on weight loss and lipid metabolism in overweight/obese adult women

Objective In recent years, people's diet has undergone tremendous changes. Excessive energy intake combined with insufficient exercise has made obesity a serious social problem. This study aims to achieve different training conditions under hypoxia and normoxia，conducting a six-week exercise training for obese overweight people. Comparing the difference in exercise weight loss between obese and overweight people in the normoxia training environment compared with hypoxia intervention, and the effect of hypoxic intervention on lipid metabolism indicators in overweight and obese people. Methods A total of 40 male overweight/obese subjects were enrolled in the study, aged 18-47 years, with no abnormal physical examination and no motor contraindications. The overweight standard is BMI≥24, and the obesity standard is BMI≥28.All subjects were randomly matched according to body weight, divided into hypoxia group and normoxia group, and exercised for 6 weeks, training 3 times a week, one time every two days. Sports training includes 30 minutes of strength training and 30 minutes of aerobic endurance training. There are 5 minutes of warm-up and finishing activities before and after training. The strength training tool is dumbbell, and the weight of the corresponding 12RM is selected according to the exercise ability of the subject, and 8 exercises are performed. They are dead lift, upright row, squat, shoulder press, calf Jump, advance lunge, biceps curl and triceps extension. Those 8 movements are divided into two small loop trainings, which complete two large groups (each small loop is completed twice).Aerobic endurance training is done using a treadmill with a slope of 0°and the speed is adjusted according to the range of the target heart rate. The target heart rate is 60%-70% at the maximum heart rate. The maximum heart rate calculation method is (220-age).The hypoxic group is equipped with a suction-type atmospheric hypoxic device and is operated under a low-oxygen environment. The oxygen content of the inhaled mixed gas is 16%, the normoxic group was exercised under normoxic conditions. Nutritional education was given to all subjects prior to the start of exercise intervention, but diet was not restricted during the intervention. Before and after intervention, height and weight were measured, and BMI was calculated. Fasting venous blood was used to detect total cholesterol (TC), total triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C), leptin (LEP) and adiponectin (ADPN). All test results are expressed as mean ± standard deviation. Comparison of data between groups, using nonparametric Mann-Whitney U test. Comparison of intra-group data, using non-parametric Wilcoxon matching for symbol level checking, the significance level was P<0.05, and the very significant level was P<0.01. Results (1) After the intervention, the body weight of both groups decreased, and the Δbody weight (P 0.05). (3) The TG change rate (P 0.05), and there was no difference between HDL-C(P>0.05). (5) LEP and ADPN in the hypoxic group increased after intervention, but there was no significant difference compared with before intervention (P>0.05). LEP and ADPN in the normoxic group decreased after intervention, and there was no difference between the LEP change rate and the ADPN change rate (P>0.05). Conclusions Under hypoxic intervention, the weight change, rate of change, and BMI change rate of overweight people were larger than those of the normoxic group. Body weight, BMI is a direct indicator of the degree of obesity in individuals. The hypoxic weight loss intervention shows greater advantages than the normoxic group from the intuitive data, which can help overweight and obese people to lose more weight under the same training load and intensity. After six weeks of training, in the hypoxic group, TC, TG and LDL-C decreased, and HDL-C increased. However, in the normoxic control group, these indicators did not show similar significant changes. It shows that through hypoxia intervention combined with exercise training, it can prevent and alleviate various chronic diseases caused by obesity more effectively, such as atherosclerosis. The other two indicators, LEP and ADPN, did not change significantly in both hypoxic and normoxic training. Conjecture there may be other mechanisms affecting the expression levels of these two hormones in the body. In summary, the researchers think the hypoxic exercise to lose weight is better than normal oxygen exercise, and it has a greater impact on most lipid metabolism indicators, which can stimulate most lipid metabolism to produce benign changes.

Enhanced biodegradation of pyridine using sequencing batch biofilm reactor under intermittent micro-aerobic condition

ABSTRACTA sequencing batch biofilm reactor under intermittent micro-aerobic or anaerobic conditions was investigated to remove pyridine at various concentrations from synthetic wastewater. The results showed that over 98% of pyridine (influent concentration ≤200 mg L−1) was degraded under intermittent micro-aerobic condition, while about 21% of pyridine was removed under anaerobic condition. Additionally, at least 60% of nitrogen located in the pyridine ring was transformed to ammonium. At the same time, the sulphate reduction was obviously inhibited under intermittent micro-aerobic conditions. The microscopic observation showed that abundant microorganisms were attached on the surface or inside of porous biocarriers under intermittent micro-aerobic conditions after a short-term period of operation. High-throughput sequencing analysis demonstrated that Azotobacter, Rhodobacteraceae and Tolumonas were the dominant species in the intermittent micro-aerobic system. The kinetic study at steady period showed that pyridine degradation was fitted well with the pseudo-first-order model (R2 > 0.96). The two possible intermediate products were identified and the possible biodegradation pathway of pyridine was proposed under micro-aerobic condition.

Targeting the Maximum Outlet Temperature of Solar Collectors

The aim of this work is to show the construction and application of design curves for solar collector networks of the flat plate type. The design curves display two important design parameters: delivery temperature and the minimum number of solar collectors in series to achieve that target temperature. Given the complex nature in which the various ambient and operating parameters interact to determine the thermal performance, it is justifiable to develop quick and reliable design methodologies to estimate the collector surface area required for a given industrial application. Since a solar thermal plant operates under intermittent conditions, it recognised that it must exhibit a flexible design to allow it to deliver the required thermal duty (load and temperature) under any set of ambient conditions. When establishing the number of collectors required for a given duty, the question to answer is if the system should be sized based on the most favourable ambient conditions or on the least favourable. This problem becomes an optimization problem but before such an approach is undertaken, some design and operating criteria must be established. This paper seeks to establish these criteria based on the concept of maximum outlet temperature attainable with the minimum number of solar collectors. A graphical representation of these two parameters is presented and a design approach of solar collector networks taking advantage of the manipulation of inlet temperature is demonstrated. The plots are derived for design parameters such as solar radiation, mass flow rate and inlet temperature using an experimentally validated thermal model. The approach is demonstrated on flat plate collector technology, but it can be extended to any other type of low temperature solar technology.

Investigating the effects of solarcure curing method on the compressive strength, microstructure and polymeric reaction of fly ash based geopolymer

This paper presents the effects of the specially designed solarcure method on the properties of geopolymer binders. The solarcure method is composed of the box-shaped chamber that works on the principles of trapping solar radiations to regulate the adequate amount of heat and temperature inside the box. Two sets of geopolymer binder mix containing low-calcium fly ash (LCFA) and high-calcium fly ash (HCFA) as a base material was developed. One part of sodium hydroxide (5 M and 10 M) solution mixed with two parts of sodium silicate was used as an alkaline activator. Mortar cubes of 50 mm size were cast and cured in three different regimes; continuous oven (CO) curing, intermittent oven (IO) curing and solarcure (SC) curing were used for the compressive strength test. For constant curing; temperature was maintained at 60 °C 24-h, whereas in intermittent conditions (IO and SC), samples were cured in three cycles; each cycle was composed of 8 h curing then 16 h cooling. For IO curing, the oven temperature was maintained at 60 °C, however for SC curing; the solar-box chamber has achieved maximum inside temperature up to 90 °C for each curing cycle. Specially designed SC technique caused up-to 56% increase in compressive strength as compared to the compressive strength of CO cured samples. SC curing also improved the microstructure properties and geopolymer reaction product.

Performance of pervious concrete pavement under various raining conditions

Pervious concrete is one of the most effective environmentally friendly products which can be used as a paving material to diminish runoff and increase safety. To better understand the behaviour of pervious concrete pavement (PCP), its performance must be extensively monitored and evaluated. The permeability rate of PCP is the key criterion in the evaluation of its performance particularly in low duty applications such as sidewalks. A few permeability rate models have been developed to date for PCP. However, the effect of raining conditions on the permeability rate has not received enough attention. The main aim of this research is to study the permeability rate models over two raining conditions i.e. continuous and intermittent for PCP in a typical sidewalk application. For this purpose, the permeability rate of PCP is tested in-situ over time on a PCP slab with various time intervals between consecutive tests to simulate continuous and intermittent raining conditions over almost four months. Based on the acquired data, it is concluded that the permeability rate of PCP over different raining conditions have a statistically significant difference. Moreover, short-term permeability rate degradation models for general, continuous, and intermittent conditions are developed using the regression method and successfully validated applying the n-fold data-split technique.

First Principle Based Control Oriented Gasoline Engine Model Including Lumped Cylinder Dynamics

A novel first principle based control oriented model of a gasoline engine is proposed which also carries diagnostic capabilities. Unlike existing control oriented models, the formulated model reflects dynamics of the faultless as well as faulty engine with high fidelity. In the proposed model, the torque production subsystem is obtained by integration of further two subsystems that is model of a single cylinder torque producing mechanism and an analytical gasoline engine cylinder pressure model. Model of a single cylinder torque producing mechanism is derived using constrained equation of motion (EOM) in Lagrangian mechanics. While cylinder pressure is evaluated using a closed form parametric analytical gasoline engine cylinder pressure model. Novel attributes of the proposed model include minimal usage of empirical relations and relatively wider region of model validity. Additionally, the model provides model based description of crankshaft angular speed fluctuations and tension in the rigid bodies. Capacity of the model to describe the system dynamics under fault conditions is elaborated with case study of an intermittent misfire condition. Model attains new capabilities based on the said novel attributes. The model is successfully validated against experimental data.

Reconstruction of Paleoclimate and Environmental Fluctuations Since the Early Holocene Period Using Organic Matter and C:N Proxy Records: A Review

ABSTRACT In this review, the shifts in organic matter (OM) accumulation and C:N ratios in lake sediments to reconstruct paleoclimate and paleo-environmental changes since the early Holocene period are presented. The C:N proxy data of total OM reflect wet climatic conditions during early Holocene (10 to 8.2 kyrs BP) due to enhanced southwest monsoon. This was followed by intermittent arid conditions during the mid and late Holocene period (8.2 to 2.8 kyr BP). Enhanced values of C:N ratio during middle to late Holocene (7.8-2.3 kyrs B.P) indicate periods with lower lake levels and minimum precipitation, while decreased C:N ratio point to stronger SW monsoon and expansion of the lakes. Further, C:N and δ13C results from the lake sediments reveal a detailed and continuous paleo-environmental changes in the relative sources of OM (allochthonous vs autochthonous). Proxy records using such natural archives have also been utilized to reconstruct past extreme events and environmental changes around the lake systems, such as causes for lake desiccation, hydrographic changes, alternations between C3 and C4 vegetation and historical disturbances in the catchment area since the early-late Holocene period coupled with the Indian summer monsoon.

Intermittent and perennial macroinvertebrate communities had similar richness but differed in species trait composition depending on flow duration

While intermittent stream research has increased dramatically in recent decades, it remains difficult to predict traits that allow biota to persist in response to reduced flows and prolonged intermittent conditions. We quantified flow duration (FD) in ten reaches of six streams previously categorized as intermittent or perennial in north-central Arkansas. Macroinvertebrates were sampled in six streams in autumn and spring following a summer when six reaches did not maintain connected flow and four that maintained connected flow. Seasonal changes in discharge altered wetted habitat availability in all reaches and differences in FD influenced the magnitude of change in habitat availability. Richness increased in all reaches in spring due to more taxa that were poor dispersers, with traits such as low crawling rate and weak female dispersal. Richness was similar across reaches in both seasons but macroinvertebrate communities differed depending on FD. Perennial reaches were characterized by large predators and rheophilic taxa, while reaches with shorter FD were characterized by shredders and non-insect taxa. This study can inform conservation and restoration activities that aim to improve or maintain connectivity between intermittent and perennial habitats to increase local biodiversity.

Nonlinear dynamics of deformation bands in aluminum–magnesium alloy in the creep test

Various types of plastic instabilities that emerge in intermittent creep have been studied experimentally for AlMg6 aluminum–magnesium alloy. It has been shown that intermittent creep exhibits threshold dynamics. The deformation step on the creep curve of amplitude is ~1–6% and begins when the rate of the preceding continuous creep attains a certain critical value. In the course of evolution of the step, the strain rate varies in the interval that spans more than two orders of magnitude, and transitions occur between different dynamic regimes of type A and B characterized by different stress drop regularity levels in the force response. Nonlinear aspects of the deformation behavior of the alloy in the intermittent creep conditions are considered.

Stability analysis of piecewise non-linear systems and its application to chaotic synchronisation with intermittent control

ABSTRACTThis paper considers a stability analysis issue of piecewise non-linear systems and applies it to intermittent synchronisation of chaotic systems. First, based on piecewise Lyapunov function methods, more general and less conservative stability criteria of piecewise non-linear systems in periodic and aperiodic cases are presented, respectively. Next, intermittent synchronisation conditions of chaotic systems are derived which extend existing results. Finally, Chua's circuit is taken as an example to verify the validity of our methods.

A new nano-power trigger circuit for battery-less power management electronics in energy harvesting systems

This paper presents a solution for battery-less power management circuits for micro-power energy converters, allowing energy harvesting systems to operate under continuous and intermittent conditions. The proposed trigger circuit is a fully passive, normally open, single pole, single throw, analog switch driven by a nano-power CMOS control unit. The trigger circuit starts in an OPEN state until the voltage, at its input terminal, reaches a high threshold, when it toggles to the CLOSED state. Once the input voltage drops below a low threshold, the trigger circuit returns to the OPEN state. In the CLOSED state, the trigger circuit creates a low resistance path between the input and output terminals, while at the OPEN state the input is isolated from the output. A first prototype was breadboarded by using discrete components for the sake of performance evaluation. Low threshold voltages (2.15V and 1.15V), sub-ohm CLOSED-state resistance, and power consumption requirements (in the order of 55.9 and 167.7nW), coupled with relatively high energy extraction capabilities are confirmed by experimental results. These features put our proposed circuit among the best of its kind in the state-of-the-art circuits.To prove the effectiveness of the proposed trigger circuit, we have included it into a custom battery-less power management circuit for a piezoelectric energy harvesting system. The system was proven to work even under intermittent operating conditions, and lock-up phenomena, related to current surge effect, were avoided.

Enraizamento de estacas de erva-baleeira em função de diferentes concentrações de ácido indol butírico e número de folhas

Varronia curassavica Jacq., black sage, is a medicinal plant with commercial interest due its anti-inflammatory properties. This species can be propagated by seeds, via vegetative propagation enabling the achievement of more uniform crops in relation to the agronomic and phytochemicals aspects. Thus, the present study aimed to evaluate the effect of different concentrations of indole butyric acid (IBA) and different leaf numbers in softwood stem cuttings of black sage plants. The experiment was conducted in august (winter season) in a factorial arrangement 3x2, with three different concentrations of IBA (0, 1500 and 3000 mg L-1) and two numbers of leaves (two leaves or one leaf). The experiment was conducted in a greenhouse under intermittent mist conditions. At 60 days after planting, the rooting percentage, number of roots per cutting, length of the three longest roots, percentage of cuttings with callus, percentage of live cuttings without roots nor callus, percentage of dead cuttings and percentage of cuttings with shoots were evaluated. There were significant differences for number of roots per cutting, which was higher at a concentration of 3000 mg L-1 compared to treatment without application of IBA (32.5%), and for percentage of cuttings with callus (15.0%), also higher were cuttings with two leaves at a concentration of 3000 mg L-1 IBA. For other factors there were no statistical differences between treatments. We conclude that the different number of leaves and IBA concentrations had little influence on the adventitious roots, mainly due to the winter season.

CFD simulations of transient load change on a high head Francis turbine

Motivated by the importance of better understanding the structural integrity of high-head hydraulic turbines operating at intermittent conditions, complete 360º steady-state and transient simulations of a Francis turbine are presented in this paper. The main target of the work has been to investigate different numerical approaches such as mesh deformation for different operating conditions. Steady-state simulations were performed at the best efficiency point (BEP) and used as initial conditions for the transient simulations considering load rejection from BEP to part load (BEP2PL) and during load acceptance from BEP to high load (BEP2HL). Simulation results were compared with experimental data available for the Francis-99 project where close agreement was found for the mesh independent solution. The transient load analyses showed general trends in accordance with the measurement reports, especially for the pressure in vaneless space that is of high importance regarding RSI effects. Some deviations were identified for the net head at load rejection for which further investigations will be conducted. All CFD simulations were performed at model scale with ANSYS CFX v. 17 at either 96 or 120 cores (2.60 GHz). The immersed boundary technique was tested during the initial stages of the project, but had to be abandoned due to severe memory requirements. Pressure amplitudes and other instantaneous results were not considered.

Reward and Feedback in the Control over Dynamic Events

On what basis do we learn to make effective decisions when faced with intermittent feedback from actions taken in a dynamic decision-making environment? In the present study we hypothesize that reward information (financial, social) may provide useful signals that can guide decision-making in these situations. To examine this, we present three experiments in which people make decisions directly towards controlling a dynamically uncertain output. We manipulate the framing of incentives (gains and losses) and the form of the incentives (financial, social), and measure their impact on decision-making performance (both in frequent and intermittent output feedback conditions). Overall, performance suffered under intermittent output feedback. Relative to social rewards, financial rewards generally improved control performance, and a gains framing (financial, social) leading to better performance than a losses framing (financial, social). To understand how rewards affect behavior in our tasks, we present a reinforcement learning model to capture the learning and performance profiles in each of our experiments. This study shows that information regarding incentives impacts the levels of exploration, the optimality of decisions-making, and the variability in the strategies people develop to control a dynamic output experienced frequently and intermittently.

Protective Role of Stem Cell Derived Extracellular Vesicles in an In Vitro Model of Hyperglycemia-Induced Endothelial Injury

Background: Adipose and bone marrow derived mesenchymal stem cells are two populations of multipotent adult stem cells with immunosuppressive, anti-inflammatory, and regenerative properties. It has been previously described that extracellular vesicles (EVs) derived from stem cells possess pro-regenerative and pro-angiogenic abilities. Hyperglycemia is a pathological condition affecting diabetic patients. Long term effects of hyperglycemia are endothelial dysfunction and vascular lesions leading to diabetic microangiopathy. The aim of the present study was to evaluate whether stem cell-derived EVs may inhibit endothelial cells dysfunction induced by hyperglycemia to mimic human microangiopathy. Methods: We set up an in vitro hyperglycemic model by culturing human microvascular endothelial cells in hyperglycemic constant or intermittent conditions for 7 days, in order to mimic a chronic damage. At day 5, endothelial cells were incubated with adipose and mesenchymal stem cell-derived EVs or vehicle alone for 48 hr. At day 7, we evaluated apoptosis, oxidative stress, and capillary-like formation ability on Matrigel. Results: Intermittent and constant high glucose models significantly decreased endothelial cell proliferation, increased number of apoptotic cells, promoted oxidation of intercellular proteins, and reduced capillary-like structure formation. Treatment with both kinds of EVs significantly restored proliferation, inhibited apoptosis and oxidation, and restored capillary-like formation. Conclusions: The results of the present study demonstrate that adipose and bone marrow mesenchymal stem cell-derived EVs may inhibit the endothelial dysfunction induced by high glucose concentration, which mimic diabetic microvascular injury.