Active-passive radial-additive friction stir repairing of mechanical hole out of dimension tolerance of AZ31 magnesium alloy

In order to avoid the depth increasing of repaired hole and eliminate the super-fine grain band in stir zone by radial-additive friction stir repairing(R-AFSR), a solid-state repairing technique of active-passive radial-additive friction stir repairing(AP-RAFSR) assisted by the truncated cone-shaped filling material was proposed in this study. The mechanical hole out of dimension tolerance of AZ31 magnesium alloy was chosen as the repaired object. The results indicated that the AP-RAFSR process rather than the R-AFSR process avoided the kissing bond in the bottom of the repairing interface under the condition of the tool pin length equal to the height of the standard mechanical hole.The continuously-distributed and large-length super-fine grain bands were eliminated in the stir zone by AP-RAFSR. The maximum tensile and compressive-shear strengths of repaired hole by AP-RAFSR reached 190.6 MPa and 138.9 MPa at 1200 rpm respectively, which were equivalent to 97.7% and 89.6% of those of the standard mechanical hole. This AP-RAFSR process assisted by the truncated cone-shaped filling material provides a new technique to obtain a no-depth-increasing, defect-free and high-strength repaired mechanical hole.

Role of OX40 in mechanisms of memory T cells in islet transplant tolerance

Objective To investigate the role of OX40 in the mechanisms of memory T cells in islet transplant tolerance. Methods The expression of OX40 on native, like memory and memory CD8 + T cells was detected by RT - PCR. Splenic T ceels from B6 mice were injected into Rag - / - mice via the tail vein,and the Rag mice were divided into three groups ( n = 8 each) :

ADVANCES OF STUDIES ON MECHANISMS OF ELECTROACUPUNCTURE ANALGESIA

The relative reports on the effects of electroacupuncture （EA） on the nervous system and neuro- transmitters, tolerance of EA and so on in recent years are reviewed so as to reveal the analgesic mechanism of EA and provide reference for clinical researches and application of EA.

Quantum generative adversarial networks based on a readout error mitigation method with fault tolerant mechanism

Readout errors caused by measurement noise are a significant source of errors in quantum circuits,which severely affect the output results and are an urgent problem to be solved in noisy-intermediate scale quantum(NISQ)computing.In this paper,we use the bit-flip averaging(BFA)method to mitigate frequent readout errors in quantum generative adversarial networks(QGAN)for image generation,which simplifies the response matrix structure by averaging the qubits for each random bit-flip in advance,successfully solving problems with high cost of measurement for traditional error mitigation methods.Our experiments were simulated in Qiskit using the handwritten digit image recognition dataset under the BFA-based method,the Kullback-Leibler(KL)divergence of the generated images converges to 0.04,0.05,and 0.1 for readout error probabilities of p=0.01,p=0.05,and p=0.1,respectively.Additionally,by evaluating the fidelity of the quantum states representing the images,we observe average fidelity values of 0.97,0.96,and 0.95 for the three readout error probabilities,respectively.These results demonstrate the robustness of the model in mitigating readout errors and provide a highly fault tolerant mechanism for image generation models.

Mechanism of Salt Tolerance in Rice

Shaheen Basma ti was evolved as a salt tolerant fine rice va riety by the Soil Salinity Research Institute,Pindi Bhattian, Pakistan. Water culture studies were conducted to investigate the physiological mechanismexercised by this variety in particular and rice plant in general to face the saline environment. Performanceof this rice variety and the concentration and uptake of ions were studied under stress of three salinity levels(30, 60 and 90 mmol L-1) created with NaCl. Recorded data indicated that shoot dry matter was notsignificantly affected by all the three levels of salinity. However, NaCl levels of 60 and 90 mmol L-1 affectedthe root dry matter significantly. Sodium concentration and uptake was enhanced significantly in root andshoot at the first level of salinity (30 mmol L-1) but thereafter the differences were non-significant, indicatingthe preferential absorption of this cation. The K concentration decreased significantly in shoots at all thelevels. The impact was less pronounced in roots as far as K absorption was concerned. The effect on Ca andMg concentrations was not significant. The values of K:Na, Ca:Na and (Ca+Mg):Na ratios in shoot and rootwere comparatively low under stress conditions, indicating that selective ion absorption may be the principalsalt tolerance mechanism of variety Shaheen Basmati when grown in a saline medium.

Effect and Mechanism of Cold Tolerant Seed-Coating Agents on the Cold Tolerance of Early Indica Rice Seedlings

To better understand the effect and mechanism of cold tolerant seed-coating agents on the cold tolerance of rice seedlings, the physiological and biochemical effects of four cold tolerant seed-coating agents （HET, YKJ, YKZYJ, and the ABA seed coating agents） on two early indica rice varieties were studied under chilling stress. The results showed that the rice seedlings treated with cold tolerant seed-coating agents under chilling stress maintained dramatically higher root vigor, POD, CAT and SOD activities, and chlorophyll content, had lower MDA content and electrolyte leakage, and accumulated more soluble sugar and free proline, when compared with the control without the treatment, and finally showed lower plant injury rate. It was indicated that the cold tolerant seed coating agent improved the ability of rice seedlings in resisting to chilling stress. YKZYJ was ranked the first in terms of the efficiency in cold tolerance among the four cold tolerant seed-coating agents tested.

Advances in Cotton Tolerance to Heavy Metal Stress and Applications to Remediate Heavy Metal-Contaminated Farmland Soil

Heavy metal-contaminated soil is one of the major environmental pollution problems of agricultural production and human health in the world.Remediation of heavy metals in soil is one of the most popular research subjects.Different remediation strategies have been reported to remove heavy metals from contaminated soil,among which phytoremediation is the most important one.Compared with other major crops,cotton shows the strongest and most widespread resistance to abiotic stresses,such as heavy metals.Although heavy metal stress adversely affects the growth and development of cotton,cotton possesses a set of sophisticated stress-resistance strategies.As the main product of cotton is nonedible fibers,which have a large biomass and strong heavy metal absorption and enrichment capacities,cotton is an ideal crop to restore heavy metal-contaminated soils and has unique advantages in terms of both ecological and economic benefits,with great application prospects.In this review,based on domestic and foreign research results in recent years,the effects of heavy metals on cotton growth and product quality were analyzed,the heavy metal absorption,accumulation,translocation and enrichment characteristics of cotton plants were summarized,and the adaptation and tolerance mechanisms of cotton to heavy metals were explored.Furthermore,the view that cotton is an effective crop to remediate heavy metal pollution in farmland soil has been proposed,and popularization and application suggestions for planting cotton to repair heavy metal pollution have been put forward to provide a reference for the comprehensive evaluation of the economic feasibility of cotton to repair heavy metal pollution in farmland soil.

PROBABILITY DAMAGE TOLERANCEEVALUATION METHOD FORMULTI-CRACKED STRUCTURE

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Study on Relationship Between Differential Proteins of Bacillus cereus LBR-4 and Its Salt Tolerance Mechanism

In order to explore the salt tolerance mechanism of Bacillus cereus LBR-4 with salinity of 14%NaCl,differential proteomic analysis of the whole protein of LBR-4 strain expressed under 14%NaCl high salinity condition and normalculture condition(1%NaCl)was studied by two-dimensional electrophoresis and mass spectrometry.The isoelectric point of most detected proteins was between pH 4-7 and the molecular weight distribution was 10-70 ku.Compared with the normal culture condition,the expression level of 118 protein spots in the whole protein expression map changed significantly(accounting for 25.2%of the total protein spots).The expression level of 78 protein spots increased significantly,including 22 new protein spots that appeared under high salt stress.The expression levels of 40 protein spots decreased significantly,including 18 protein spots that disappeared under high salt stress.By mass spectrometry,six distinct differentially expressed protein spotswere dihydroxy acid dehydratase,cell division protein FtsZ,iron sulfur cluster synthesis protein SufD,unknown carboxylase YngE,hypothetical acetaldehyde dehydrogenase DhaS and phenylalanine acid tRNA ligase alpha subunit.It was speculated that under high salt stress,the cells had protective measures and the secretion of intracellular compatible solutes increased.The iron and sulfur clusters involved in various physiological reactions also activated the stressful suf synthesis pathway,and therate of cell division and reproduction was also slowed down and ensured the normal progress of physiological reactions inthe cells.

Neuroprotection induced by NMDA preconditioning as a strategy to understand brain tolerance mechanism

Excitotoxicity refers to toxicity caused by abnormal concentrations of glutamate in the synaptic cleft that may lead to neuronal death. Since its description, the phenomenon of glutamatergic excitotoxicity has been implicated in the physiopathology of a wide range of neurological and psychiatric disorders, from acute brain damage such as traumatic brain injury, ischemia as well as chronic condi- tions like epilepsy, depression and neurodegenerative pathologies such as Huntington＇s, Parkinson＇s and Alzheimer＇s diseases. Exces- sive stimulation of glutamatergic receptors, mainly N-methyl-D-as- partate （NMDA） receptors （NMDAR）, can have numerous adverse effects on the cell viability, including increased nitric oxide release （NO）, activation of proteases, increased production of reactive oxygen （ROS） and nitrogen （RNS） species and massive influx of calcium ions （Ca2＋）, resulting in cell death. Thus, the use of strategies that modulate the excitotoxic cell damage represents a perspective for the treatment of diseases such as Parkinson＇s and Alzheimer＇s diseases, ischemia, traumatic brain injury （TBI） and seizures.

Physiological Evaluation of Wheat (<i>Triticum aestivum</i>L.) Genotypes at Pre-Anthesis Stage under Heat Stress Conditions

Experiments were conducted to analyze effects of high temperature stress on wheat at pre-anthesis growth stage. Twenty four wheat genotypes exposed to a sub optimal temperature (>35°C) which showed altered physiological, biochemical and agronomic characteristics. Accumulation of proline, presence of new protein bands and higher antioxidant enzyme activity in leaves of G.7 and G.17 reflects their better adaptive response under heat stress conditions. G.17 and G.19 showed least reduction in number of spikelets per spike, biological yield and 100 grain weight. It was inferred that the genotypes G.7, G.17 and G.19 exhibited greater heat tolerance and could be recommended for cultivation under heat stress conditions.

Ischemic postconditioning protects against ischemic brain injury by up-regulation of acid-sensing ion channel 2a

Ischemic postconditioning renders brain tissue tolerant to brain ischemia,thereby alleviating ischemic brain injury.However,the exact mechanism of action is still unclear.In this study,a rat model of global brain ischemia was subjected to ischemic postconditioning treatment using the vessel occlusion method.After 2 hours of ischemia,the bilateral common carotid arteries were blocked immediately for 10 seconds and then perfused for 10 seconds.This procedure was repeated six times.Ischemic postconditioning was found to mitigate hippocampal CA1 neuronal damage in rats with brain ischemia,and up-regulate acid-sensing ion channel 2a expression at the m RNA and protein level.These findings suggest that ischemic postconditioning up-regulates acid-sensing ion channel 2a expression in the rat hippocampus after global brain ischemia,which promotes neuronal tolerance to ischemic brain injury.

Adaptive Dimensional Learning with a Tolerance Framework for the Differential Evolution Algorithm

The Differential Evolution(DE)algorithm,which is an efficient optimization algorithm,has been used to solve various optimization problems.In this paper,adaptive dimensional learning with a tolerance framework for DE is proposed.The population is divided into an elite subpopulation,an ordinary subpopulation,and an inferior subpopulation according to the fitness values.The ordinary and elite subpopulations are used to maintain the current evolution state and to guide the evolution direction of the population,respectively.The inferior subpopulation learns from the elite subpopulation through the dimensional learning strategy.If the global optimum is not improved in a specified number of iterations,a tolerance mechanism is applied.Under the tolerance mechanism,the inferior and elite subpopulations implement the restart strategy and the reverse dimensional learning strategy,respectively.In addition,the individual status and algorithm status are used to adaptively adjust the control parameters.To evaluate the performance of the proposed algorithm,six state-of-the-art DE algorithm variants are compared on the benchmark functions.The results of the simulation show that the proposed algorithm outperforms other variant algorithms regarding function convergence rate and solution accuracy.

Radial Additive Friction Stir Repairing of Mechanical Hole Out of Dimension Tolerance of AZ31 Magnesium Alloy Assisted by Stationary Shoulder:Process and Mechanical Properties

Radial additive friction stir repairing(R-AFSR)assisted by stationary shoulder was put forward in the present study,which can be employed to repair the mechanical hole out of dimension tolerance of AZ31 magnesium alloy sheet.The results show that the stationary shoulder has sealed-barrier,heat-sink and extra-forging effects.The heat-sink effect improves the microstructure uniformity along the stir zone(SZ)thickness and the surface appearance of repaired hole,and the sealedbarrier and extra-forging effects eliminate the super-fine grain band in the SZ.Therefore,these three effects improve the formation quality of repaired region,thereby enhancing the mechanical properties of repaired mechanical hole compared with conventional R-AFSR.The tensile and compressive shear strengths of the repaired hole by stationary shoulder R-AFSR both increase first and then decrease when the rotating speed changes from 1200 to 1800 rpm,and these maximum values,respectively,reach 190±3 MPa and 64.5±2 MPa at 1400 rpm.The addition of stationary shoulder during R-AFSR can obtain a higher-quality repaired hole and broaden the repairing process window.

Design of the longitudinal-gradient dipole magnets for HEPS

TheHigh Energy Photon Source(HEPS)is the fourth generation light source with high brilliance and lowemittance.The lattice of the storage ring consists of five different dipoles with longitudinal gradients.The longitudinal-gradient dipoles(BLGs)are permanent magnets.This paper presents the construction of BLGs and the magnetic field results using OPERA3D.By optimizing the shape of the polar surface,the magnetic field uniformity is optimized to about 2×10−4.With some adjustable screws,the magnetic field is controlled accurately.Some temperature compensation shunt sheets are arranged to make the temperature stability of magnets better than±50 ppm/°C.At last,the mechanical tolerances of the magnets are studied.