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Characterization of the effects of hyaluronan oligosaccharides on human gut microbiota using a simulated batch fermentation system
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作者 Xinwei Gao Hongkang Zhu +6 位作者 Litao Hu Jieyu Sun Wenjie Zuo Ping Liu Yang Wang Guocheng Du Zhen Kang 《Food Science and Human Wellness》 2025年第6期2172-2184,共13页
The prebiotic effects of hyaluronan(HA)are widely recognized,contributing to improved gut health and immune modulation.Despite its extensive use as dietary supplement,the specific interactions between HA oligosacchari... The prebiotic effects of hyaluronan(HA)are widely recognized,contributing to improved gut health and immune modulation.Despite its extensive use as dietary supplement,the specific interactions between HA oligosaccharides(o-HAs)and the gut microbiome remain largely unexplored.To investigate its role and metabolic fate in gut homeostasis,200 mg/day of o-HAs(average molecule weight 1 kDa)were added to an automated computer-controlled SIMulator of the Gastrointestinal tract(SIMGI).The results revealed a significant reshaping of the intestinal flora composition by o-HAs,notably reducing the Firmicutes/Bacteroides ratio.Fermentation of o-HAs by gut microbiota significantly increased the abundance of Bifidobacterium,Prevotellaceae_Prevotella,Dialister,Eubacterium,and Sutterella,but decreased that of Catenibacterium,Oscillospira,Klebsiella,and Citrobacter(P<0.05).This corresponded with significant enhancements in the content of short-chain fatty acids(SCFAs)such as acetic acid,propionic acid and n-butyric acid,highlighting the significant impact of o-HAs at the genus level.Furthermore,analysis of microbial function predicted the downregulation of pathological events in nine human diseases,particularly infectious ones(parasitic and bacterial).Potential inhibitions were observed in metabolic pathways associated with pentose and glucuronate interconversions as well as cationic antimicrobial peptide resistance.These findings underscore the in vitro prebiotic effects of o-HAs and their potential relevance in managing diverticular diseases or preventing metabolic disorders through the regulation of gut microbiota. 展开更多
关键词 Hyaluronan oligosaccharides Colon simulation system FERMENTATION Fecal microbiota Short chain fatty acid
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Highly stable self-rectifying memristor integrated arrays for simulated annealing neuromorphic computing
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作者 Jiang Bian Yingfang Zhu +13 位作者 Shaoan Yan Yin Tang Jiayue Guo Gang Li Jiang Zhao Qing Zhong Qingjiang Li Sen Liu Rui Liu Qilai Chen Yongguang Xiao Xiaojian Zhu Qinghua Li Minghua Tang 《Nano Research》 2026年第1期1089-1101,共13页
This work presents a high-stability self-rectifying memristor(SRM)array based on the Pt/TaO_(x)/Ti structure,with an indepth investigation of the performance and potential applications of the device.The device demonst... This work presents a high-stability self-rectifying memristor(SRM)array based on the Pt/TaO_(x)/Ti structure,with an indepth investigation of the performance and potential applications of the device.The device demonstrates excellent rectification and on/off ratios,along with low-power readout,multi-state storage,and multi-level switching capabilities,highlighting its practicality and adaptability.Notably,the device exhibits outstanding fluctuation suppression and exceptional uniformity.The coefficient of variation(CV)of the rectification ratio,calculated as 0.11497 at 3 V,indicates its high stability under multiple cycles and low-voltage operation,making it well-suited for large-scale integration and operational applications.Moreover,the stability of the rectification ratio further reinforces its potential as a hardware foundation for large-scale inmemory computing systems.By combining the neuromorphic characteristics of the device with a simulated annealing algorithm and optimizing the annealing temperature function,the system emulates biological neuron behavior,enabling fast and efficient image restoration tasks.Experimental results demonstrate that this approach significantly outperforms traditional algorithms in both optimization speed and repair accuracy.The present study offers a novel perspective for the design of in-memory computing hardware and showcases promising applications in neuromorphic computing and image processing. 展开更多
关键词 self-rectifying memristor in-memory computing simulated annealing algorithm neuromorphic computing
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Automatic gating and riser system design and defect control for K4169 superalloy guide blade casting based on parametric 3D modeling-simulation integrated system
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作者 Le-chuan Li Ya-jun Yin +4 位作者 Bing-zheng Fan Guo-yan Shui Xiao-yuan Ji Jian-xin Zhou Lei Jin 《China Foundry》 2026年第1期20-30,共11页
Automation and intelligence have become the primary trends in the design of investment casting processes.However,the design of gating and riser systems still lacks precise quantitative evaluation criteria.Numerical si... Automation and intelligence have become the primary trends in the design of investment casting processes.However,the design of gating and riser systems still lacks precise quantitative evaluation criteria.Numerical simulation plays a significant role in quantitatively evaluating current processes and making targeted improvements,but its limitations lie in the inability to dynamically reflect the formation outcomes of castings under varying process conditions,making real-time adjustments to gating and riser designs challenging.In this study,an automated design model for gating and riser systems based on integrated parametric 3D modeling-simulation framework is proposed,which enhances the flexibility and usability of evaluating the casting process by simulation.Firstly,geometric feature extraction technology is employed to obtain the geometric information of the target casting.Based on this information,an automated design framework for gating and riser systems is established,incorporating multiple structural parameters for real-time process control.Subsequently,the simulation results for various structural parameters are analyzed,and the influence of these parameters on casting formation is thoroughly investigated.Finally,the optimal design scheme is generated and validated through experimental verification.Simulation analysis and experimental results show that using a larger gate neck(24 mm in side length) and external risers promotes a more uniform temperature distribution and a more stable flow state,effectively eliminating shrinkage cavities and enhancing process yield by 15%. 展开更多
关键词 numerical simulation automatic design investment casting parametric 3D modeling gating and riser system
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Changes in Winter Stratospheric Circulation in CMIP5 Scenarios Simulated by the Climate System Model FGOALS-s2 被引量:9
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作者 任荣彩 杨扬 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2012年第6期1374-1389,共16页
Diagnosis of changes in the winter stratospheric circulation in the Fifth Coupled Model Intercomparison Project (CMIP5) scenarios simulated by the Flexible Global Ocean-Atmosphere-Land System model, second version s... Diagnosis of changes in the winter stratospheric circulation in the Fifth Coupled Model Intercomparison Project (CMIP5) scenarios simulated by the Flexible Global Ocean-Atmosphere-Land System model, second version spectrum (FGOALS-s2), indicates that the model can generally reproduce the present climatology of the stratosphere and can capture the general features of its long-term changes during 1950-2000, including the global stratospheric cooling and the strengthening of the westerly polar jet, though the simulated polar vortex is much cooler, the jet is much stronger, and the projected changes are generally weaker than those revealed by observation data. With the increase in greenhouse gases (GHGs) effect in the historical simu- lation from 1850 to 2005 (called the HISTORICAL run) and the two future projections for Representative Concentration Pathways (called the RCP4.5 and RCP8.5 scenarios) from 2006 to 2100, the stratospheric response was generally steady, with an increasing stratospheric cooling and a strengthening polar jet ex- tending equatorward. Correspondingly, the leading oscillation mode, defined as the Polar Vortex Oscillation (PVO), exhibited a clear positive trend in each scenario, confirming the steady strengthening of the polar vortex. However, the positive trend of the PVO and the strengthening of the polar jet were not accompa- nied by decreased planetary-wave dynamical heating, suggesting that the cause of the positive PVO trend and the polar stratospheric cooling trend is probably the radiation cooling effect due to increase in GHGs. Nevertheless, without the long-term linear trend, the temporal variations of the wave dynamic heating, the PVO, and the polar stratospheric temperature are still closely coupled in the interannual and decadal time scales. 展开更多
关键词 simulated changes STRATOSPHERE CMIP5 FGOALS-s2
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Multiobjective Optimization of Simulated Moving Bed by Tissue P System 被引量:8
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作者 黄亮 孙磊 +1 位作者 王宁 金晓明 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第5期683-690,共8页
The binaphthol enantiomers separation process using simulation moving bed technology is simulated with the true moving bed approach (TMB). In order to systematically optimize the process with multiple productive obj... The binaphthol enantiomers separation process using simulation moving bed technology is simulated with the true moving bed approach (TMB). In order to systematically optimize the process with multiple productive objectives, this article develops a variant of tissue P system (TPS). Inspired by general tissue P systems, the special TPS has a tissue-like structure with several membranes. The key rules of each membrane are the communication rule and mutation rule. These characteristics contribute to the diversity of the population, the conquest of the multimodal of objective function, and the convergence of algorithm. The results of comparison with a popular algorithm——the non-dominated sorting genetic algorithm 2(NSGA-2) illustrate that the new algorithm has satisfactory performance. Using the algorithm, this study maximizes synchronously several conflicting objectives, purities of different products, and productivity. 展开更多
关键词 simulated moving bed tissue P systems multiobjective optimization Pareto optimality evolutionary algorithm binaphthol enantiomers separation process
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Cascade refrigeration system synthesis based on hybrid simulated annealing and particle swarm optimization algorithm 被引量:2
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作者 Danlei Chen Yiqing Luo Xigang Yuan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第6期244-255,共12页
Cascade refrigeration system(CRS)can meet a wider range of refrigeration temperature requirements and is more energy efficient than single-refrigerant refrigeration system,making it more widely used in low-temperature... Cascade refrigeration system(CRS)can meet a wider range of refrigeration temperature requirements and is more energy efficient than single-refrigerant refrigeration system,making it more widely used in low-temperature industry processes.The synthesis of a CRS with simultaneous consideration of heat integration between refrigerant and process streams is challenging but promising for significant cost saving and reduction of carbon emission.This study presented a stochastic optimization method for the synthesis of CRS.An MINLP model was formulated based on the superstructure developed for the CRS,and an optimization framework was proposed,where simulated annealing algorithm was used to evolve the numbers of pressure/temperature levels for all sub-refrigeration systems,and particle swarm optimization algorithm was employed to optimize the continuous variables.The effectiveness of the proposed methodology was verified by a case study of CRS optimization in an ethylene plant with 21.89%the total annual cost saving. 展开更多
关键词 Optimal design Process systems Particle swarm optimization simulated annealing Mathematical modeling
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Effects of simulated microgravity on antioxidant system in testis of adult rats 被引量:2
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作者 Dangxia Zhou Shudong Qiu Ying Sun Jie Zhang Haixue Wang 《Journal of Nanjing Medical University》 2006年第4期234-237,共4页
Objective: To study the effects of simulated microgravity induced by tail-suspension on histological structures and antioxidant system in testis of adult rats. Methods: Forty Spraque-Dawley adult male rats were rand... Objective: To study the effects of simulated microgravity induced by tail-suspension on histological structures and antioxidant system in testis of adult rats. Methods: Forty Spraque-Dawley adult male rats were randomly divided into four groups, two experimental groups and two synchronic control groups. Rats in the two experimental groups were tail-suspended for 14 d and 28 d respectively, then serum hormone, testicular morphology and biochemical changes were evaluated. Results: Compared with the synchronic controls, serum testosterone (T) levels and testicular superoxide dismutase (SOD) significantly decreased(P 〈 0.05), while testicular malondialdehyde(MDA) significantly increased (P 〈 0.05) in tail-suspended rats. The changes were more prominent in the 28 d tail-suspended rats. In addition, hematoxylin and eosin (HE) staining showed that seminiferous tubules atrophied, spermatogenic cells decreased, and seminiferous epithelial cells disintegrated and shed, abnormal multinucleated giant cells appeared and the lumina were azoospermic in tail-suspended rats. ConcIusion: Simulated microgravity induced by tailsuspension has a harmful effect on male reproduction of adult rats by decreasing the ability of testicular antioxidant defense. 展开更多
关键词 simulated microgravity TAIL-SUSPENSION TESTIS RAT oxidative stress
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Understanding Simulated Causes of Damaging Surface Winds in a Derecho-Producing Mesoscale Convective System near the East China Coast Based on Convection-Permitting Simulations 被引量:1
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作者 Liping LUO Ming XUE +3 位作者 Xin XU Lijuan LI Qiang ZHANG Ziqi FAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第11期2112-2130,共19页
A mesoscale convective system(MCS) occurred over the East China coastal provinces and the East China Sea on 30April 2021, producing damaging surface winds near the coastal city Nantong with observed speeds reaching 45... A mesoscale convective system(MCS) occurred over the East China coastal provinces and the East China Sea on 30April 2021, producing damaging surface winds near the coastal city Nantong with observed speeds reaching 45 m s^(–1). A simulation using the Weather Research and Forecasting model with a 1.5-km grid spacing generally reproduces the development and subsequent organization of this convective system into an MCS, with an eastward protruding bow segment over the sea. In the simulation, an east-west-oriented high wind swath is generated behind the gust front of the MCS. Descending dry rear-to-front inflows behind the bow and trailing gust front are found to feed the downdrafts in the main precipitation regions. The inflows help to establish spreading cold outflows and enhance the downdrafts through evaporative cooling. Meanwhile, front-to-rear inflows from the south are present, associated with severely rearward-tilted updrafts initially forming over the gust front. Such inflows descend behind(north of) the gust front, significantly enhancing downdrafts and near-surface winds within the cold pool. Consistently, calculated trajectories show that these parcels that contribute to the derecho originate primarily from the region ahead(south) of the east-west-oriented gust front, and dry southwesterly flows in the low-to-middle levels contribute to strong downdrafts within the MCS. Moreover, momentum budget analyses reveal that a large westward-directed horizontal pressure gradient force within the simulated cold pool produced rapid flow acceleration towards Nantong. The analyses enrich the understanding of damaging wind characteristics over coastal East China and will prove helpful to operational forecasters. 展开更多
关键词 damaging surface winds convection-permitting simulations mesoscale convective system gust front cold pool
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Video-assisted bystander cardiopulmonary resuscitation improves the quality of chest compressions during simulated cardiac arrests: A systemic review and meta-analysis 被引量:1
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作者 Dong-Feng Pan Zheng-Jun Li +2 位作者 Xin-Zhong Ji Li-Ting Yang Pei-Feng Liang 《World Journal of Clinical Cases》 SCIE 2022年第31期11442-11453,共12页
BACKGROUND It remains unclear whether video aids can improve the quality of bystander cardiopulmonary resuscitation(CPR).AIM To summarize simulation-based studies aiming at improving bystander CPR associated with the ... BACKGROUND It remains unclear whether video aids can improve the quality of bystander cardiopulmonary resuscitation(CPR).AIM To summarize simulation-based studies aiming at improving bystander CPR associated with the quality of chest compression and time-related quality parameters.METHODS The systematic review was conducted according to the PRISMA guidelines.All relevant studies were searched through PubMed,EMBASE,Medline and Cochrane Library databases.The risk of bias was evaluated using the Cochrane collaboration tool.RESULTS A total of 259 studies were eligible for inclusion,and 6 randomised controlled trial studies were ultimately included.The results of meta-analysis indicated that video-assisted CPR(V-CPR)was significantly associated with the improved mean chest compression rate[OR=0.66(0.49-0.82),P<0.001],and the proportion of chest compression with correct hand positioning[OR=1.63(0.71-2.55),P<0.001].However,the difference in mean chest compression depth was not statistically significant[OR=0.18(-0.07-0.42),P=0.15],and V-CPR was not associated with the time to first chest compression compared to telecommunicator CPR[OR=-0.12(-0.88-0.63),P=0.75].CONCLUSION Video real-time guidance by the dispatcher can improve the quality of bystander CPR to a certain extent.However,the quality is still not ideal,and there is a lack of guidance caused by poor video signal or inadequate interaction. 展开更多
关键词 Dispatcher-assisted cardiopulmonary resuscitation Video Quality of chest compressions simulated cardiac arrests
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The Development of a Simulated Sediment Dosing Apparatus for Deposition Research in Wastewater Collection Systems 被引量:1
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作者 David Campbell Sean Mushin Craig Saunders 《Journal of Water Resource and Protection》 2018年第5期493-506,共14页
Water conservation initiatives promote installation of water efficient and low-flow appliances in waste water collection systems. This has resulted in lower flow rates in those systems than the intended design loading... Water conservation initiatives promote installation of water efficient and low-flow appliances in waste water collection systems. This has resulted in lower flow rates in those systems than the intended design loading, causing solid deposition and sedimentation in some areas. A joint UKWIR/EPSRC CASE grant (14440031) has funded the work described in this paper which investigates sedimentation and solid deposition in building drainage system pipes. The purpose of this paper is to detail the design, calibration and operation of a sediment dosing apparatus to simulate sedimentation rates and explore possible solutions to this issue with a full scale laboratory model based on real site data. The methodology adopted is an experimental approach, where tests have been conducted on the sediment dosing apparatus based on calculations and observations to determine an appropriate sediment dosing regime representative of typical systems. Further tests were conducted with the addition of everyday household products to investigate their effects on sedimentation. The results indicated that a suitable dosing rate was approximately 12% weight-to-volume (w/v) of a fine sand with a known particle size distribution, diluted 1:5 in a clean water base flow. It was also shown that the addition of the household products added to the problem of sedimentation within drainage systems. The results give excellent correlation to real site data, with deposition depth and distribution comparable to measured site data to within 10%. The deposition was achieved within three hours, which approximated six weeks deposition in the live site used in the study. This straightforward investigation details the design, construction and testing of a device to cause accelerated sedimentation in a full scale model of a building drainage system. This is the first step in the process of updating research underpinning our understanding of the behaviour of these systems under conditions of low flow rates caused by water conservation, sedimentation, and the use of common household additives. It will be used to improve simulation of water flow and solid transport in sediment-laden systems. Specifically, the results will be used to determine refinements required to a specific drainage simulation model (DRAINET), which currently has an unquantified sedimentation component. This work is part of a larger body of current research funded by two joint EPSRK/UKWIR grants. 展开更多
关键词 Water CONSERVATION DEPOSITION Modelling Computer Simulation Empirical Model SITE Sampling
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Biodegradation Behavior of Starch in Simulated White Water System of Old Corrugated Cardboard Pulping Process 被引量:2
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作者 Jinhuan Guo Liqin Liu +7 位作者 Xiaohong Zhang Zhengbai Cheng Shuangxi Nie Haibing Cao Na Li Md Manik Mian Xingye An Hongbin Liu 《Paper And Biomaterials》 CAS 2023年第1期50-62,共13页
Considering the serious barriers/issues induced by the accumulated starch generated in white water system of old corrugated cardboard(OCC)pulping process,large amounts of accumulated starch in white water would be dec... Considering the serious barriers/issues induced by the accumulated starch generated in white water system of old corrugated cardboard(OCC)pulping process,large amounts of accumulated starch in white water would be decomposed by microorganisms and could not be utilized,thereby resulting in severe resource wastage and environmental pollution.This study mainly explored the effects of biodegradation/hydrolysis conditions of the two types of starch substrates(native starch and enzymatically(α-amylase)hydrolyzed starch),which were treated via microorganism degradation within the simulated white water from OCC pulping system and their biodegradation products on the key properties were characterized via X-ray diffraction(XRD),Fourier-transform infrared spectroscopy(FT-IR),and gel permeation chromatography(GPC)technologies.The effects of system temperature,pH value,starch concentration,and biodegradation time on starch biodegradation ratio and the characteristics of obtained biodegradated products from the two types of starches were studied.In addition,the effect ofα-amylase dosage on the biodegradation ratio of enzymatically hydrolyzed starch and its properties was investigated.It was found that the native starch presented a maximal degradation ratio at a system temperature of 55℃and pH value range of 5-7,respectively,the corresponding starch concentration within simulated white water system was 200 mg/L.Whereas the enzymatically hydrolyzed starch exhibited a highest degradation ratio at a system temperature of 50℃and pH value of 5.5,respectively,and the corresponding starch concentration within simulated white water system was 100 mg/L.It was verified that native starch is more readily bio-hydrolyzed and biodegradation-susceptive by microorganisms in simulated white water system of OCC pulping process,while the enzymatically hydrolyzed starch exhibits better biodegradation/hydrolysis resistance to the microbial degradation than that of native starch.This study provides a practical and interesting approach to investigate the starch hydrolysis or biodegradation behaviors in white water system of OCC pulping process,which would greatly contribute to the full recycling and valorized application of starch as a versatile additive during paperboard production. 展开更多
关键词 STARCH OCC pulping white water simulation hydrolysis resistance biodegradation behavior
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Müller cells are activated in response to retinal outer nuclear layer degeneration in rats subjected to simulated weightlessness conditions 被引量:1
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作者 Yuxue Mu Ning Zhang +7 位作者 Dongyu Wei Guoqing Yang Lilingxuan Yao Xinyue Xu Yang Li Junhui Xue Zuoming Zhang Tao Chen 《Neural Regeneration Research》 SCIE CAS 2025年第7期2116-2128,共13页
A microgravity environment has been shown to cause ocular damage and affect visual acuity,but the underlying mechanisms remain unclear.Therefore,we established an animal model of weightlessness via tail suspension to ... A microgravity environment has been shown to cause ocular damage and affect visual acuity,but the underlying mechanisms remain unclear.Therefore,we established an animal model of weightlessness via tail suspension to examine the pathological changes and molecular mechanisms of retinal damage under microgravity.After 4 weeks of tail suspension,there were no notable alterations in retinal function and morphology,while after 8 weeks of tail suspension,significant reductions in retinal function were observed,and the outer nuclear layer was thinner,with abundant apoptotic cells.To investigate the mechanism underlying the degenerative changes that occurred in the outer nuclear layer of the retina,proteomics was used to analyze differentially expressed proteins in rat retinas after 8 weeks of tail suspension.The results showed that the expression levels of fibroblast growth factor 2(also known as basic fibroblast growth factor)and glial fibrillary acidic protein,which are closely related to Müller cell activation,were significantly upregulated.In addition,Müller cell regeneration and Müller cell gliosis were observed after 4 and 8 weeks,respectively,of simulated weightlessness.These findings indicate that Müller cells play an important regulatory role in retinal outer nuclear layer degeneration during weightlessness. 展开更多
关键词 glial fibrous acidic protein GLIOSIS Müller cells nerve growth factor neural differentiation neurodegeneration proteomic retinal degeneration retinal outer nuclear layer simulated weightlessness
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Effects of Bifidobacterium lactis BLa80 on fecal and mucosal flora and stem cell factor/c-kit signaling pathway in simulated microgravity rats 被引量:1
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作者 Ping Zhang Ying Zhu +7 位作者 Pu Chen Tong Zhou Zhe-Yi Han Jun Xiao Jian-Feng Ma Wen Ma Peng Zang Ying Chen 《World Journal of Gastroenterology》 SCIE CAS 2025年第1期93-109,共17页
BACKGROUND Simulated microgravity environment can lead to gastrointestinal motility disturbance.The pathogenesis of gastrointestinal motility disorders is closely related to the stem cell factor(SCF)/c-kit signaling p... BACKGROUND Simulated microgravity environment can lead to gastrointestinal motility disturbance.The pathogenesis of gastrointestinal motility disorders is closely related to the stem cell factor(SCF)/c-kit signaling pathway associated with intestinal flora and Cajal stromal cells.Moreover,intestinal flora can also affect the regulation of SCF/c-kit signaling pathway,thus affecting the expression of Cajal stromal cells.Cajal cells are the pacemakers of gastrointestinal motility.AIM To investigate the effects of Bifidobacterium lactis(B.lactis)BLa80 on the intestinal flora of rats in simulated microgravity and on the gastrointestinal motility-related SCF/c-kit pathway.METHODS The internationally recognized tail suspension animal model was used to simulate the microgravity environment,and 30 rats were randomly divided into control group,tail suspension group and drug administration tail suspension group with 10 rats in each group for a total of 28 days.The tail group was given B.lactis BLa80 by intragastric administration,and the other two groups were given water intragastric administration,the concentration of intragastric administration was 0.1 g/mL,and each rat was 1 mL/day.Hematoxylin&eosin staining was used to observe the histopathological changes in each segment of the intestine of each group,and the expression levels of SCF,c-kit,extracellular signal-regulated kinase(ERK)and p-ERK in the gastric antrum of each group were detected by Western blotting and PCR.The fecal flora and mucosal flora of rats in each group were detected by 16S rRNA.RESULTS Simulated microgravity resulted in severe exfoliation of villi of duodenum,jejunum and ileum in rats,marked damage,increased space between villi,loose arrangement,shortened columnar epithelium of colon,less folds,narrower mucosal thickness,reduced goblet cell number and crypts,and significant improvement after probiotic intervention.Simulated microgravity reduced the expressions of SCF and c-kit,and increased the expressions of ERK and P-ERK in the gastric antrum of rats.However,after probiotic intervention,the expressions of SCF and ckit were increased,while the expressions of ERK and P-ERK were decreased,with statistical significance(P<0.05).In addition,simulated microgravity can reduce the operational taxonomic unit(OTU)of the overall intestinal flora of rats,B.lactis BLa80 can increase the OTU of rats,simulated microgravity can reduce the overall richness and diversity of stool flora of rats,increase the abundance of firmicutes in stool flora of rats,and reduce the abundance of Bacteroides in stool flora of rats,most of which are mainly beneficial bacteria.Simulated microgravity can increase the overall richness and diversity of mucosal flora,increase the abundance of Bacteroides and Desulphurides in the rat mucosal flora,and decrease the abundance of firmicutes,most of which are proteobacteria.After probiotics intervention,the overall Bacteroidetes trend in simulated microgravity rats was increased.CONCLUSION B.lactis BLa80 can ameliorate intestinal mucosal injury,regulate intestinal flora,inhibit ERK expression,and activate the SCF/c-kit signaling pathway,which may have a facilitating effect on gastrointestinal motility in simulated microgravity rats. 展开更多
关键词 simulated microgravity Rat Intestinal flora Gastrointestinal motility Stem cell factor/c-kit signaling pathway
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Herba Epimedii′s biotransformation in vitro simulated gastrointestinal digestion and faecal fermentation systems
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作者 LI Ben ZHANG Xiao-yao +1 位作者 Alberto CP DIAS ZHANG Xiao-ying 《中国药理学与毒理学杂志》 CAS 北大核心 2021年第10期732-732,共1页
OBJECTIVE Epimedium is rich in a variety of beneficial active ingredients,and has been widely used in the ethnopharmacological practices,however,its biotransformation in gastrointestinal digestions remain unclear.This... OBJECTIVE Epimedium is rich in a variety of beneficial active ingredients,and has been widely used in the ethnopharmacological practices,however,its biotransformation in gastrointestinal digestions remain unclear.This study aimed to investigate the dynamic changes of components and biological activity of Epimedium in the in vitro simulated digestion and subsequent human faecal fermentation.METHODS The models of in vitro simulated saliva,gastric and intestinal digestion,as well as colonic fermentation were constructed to simulate the digestion process of Epimedium.The dynamic changes of components of Epimedium during the simulated digestions in vitro and subsequent human faecal fermentation were investigated by UPLC-MS,HPLC-DAD combined with principal component analysis(PCA)and multi-ingredient quantitative analysis.RESULTS A variety of metabolites with high contents were produced after 0.5 h of intestinal digestion and colonic fermentation 0.5 h.Application of PCA to HPLC data showed the obvious separation of colonic fermentation 0.5 h stage samples from other colonic fermentation stages samples(24,48 and 72 h).Additionally,non-digestion and saliva digestion stage samples clustered together,and there was obvious separation between intestinal digestion samples and gastric digestion samples.The contents of epimedium C,icariin and baohuside I all increased significantly after intestinal digestion[58.70±7.08,47.15±5.68 and(12.78±0.55)mg·g^(-1)]compared with gastric digestion[29.00±5.65,17.40±4.55 and(2.77±0.19)mg·g^(-1)].There were significant differences between sample after 0.5 h of colonic fermentation[64.22±9.32,51.26±6.33 and(16.68±3.19)mg·g^(-1)]and other time points(24,48 and 72 h)in components and the contents of active ingredient,and the content of these components all decreased with the fermentation time.The ability of scavenging ABTS free radicals[IC50=(0.29±0.02)g·L^(-1)]increased significantly compared with gastric digestion[(1.57±0.02)g·L^(-1)],and after 0.5 h of colonic fermentation,the ability also increased significantly.CONCLUSION Gastrointestinal digestion had a significant impact on the contents of active components in Epimedium,and the metabolism of these components mainly occurred in the colon.The intestinal digestion and colonic fermentation significantly improved the anti-ABTS activity of epimedium. 展开更多
关键词 EPIMEDIUM simulated gastrointestinal digestion faecal fermentation BIOTRANSFORMATION
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Effects of mesoscale gravity waves on sporadic E simulated by a one-dimensional dynamic model 被引量:1
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作者 Xu Zhou ZeZhong Li +1 位作者 XinAn Yue LiBo Liu 《Earth and Planetary Physics》 EI CAS 2025年第1期1-9,共9页
In addition to being driven by tidal winds,the sporadic E(Es)layers are modulated by gravity waves(GWs),although the effects are not yet comprehensively understood.In this article,we discuss the effects of mesoscale G... In addition to being driven by tidal winds,the sporadic E(Es)layers are modulated by gravity waves(GWs),although the effects are not yet comprehensively understood.In this article,we discuss the effects of mesoscale GWs on the Es layers determined by using a newly developed model,MISE-1D(one-dimensional Model of Ionospheric Sporadic E),with low numerical dissipation and high resolution.Driven by the wind fields resolved by the high-resolution version of the Whole Atmosphere Community Climate Model with thermosphere and ionosphere extension(WACCM-X),the MISE-1D simulation revealed that GWs significantly influence the evolution of the Es layer above 100 km but have a very limited effect at lower altitudes.The effects of GWs are diverse and complex,generally including the generation of fluctuating wavelike structures on the Es layer with frequencies similar to those of the GWs.The mesoscale GWs can also cause increases in the density of Es layers,or they can disperse or diffuse the Es layers and increase their thickness.In addition,the presence of GWs is a key factor in sustaining the Es layers in some cases. 展开更多
关键词 sporadic E ion tidal layer gravity waves numerical simulation
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Development of Simulated Testbed for Electrical Power Subsystem of a Certain Kind of Satellite
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作者 Ding, Caihong Jiang, Xingwei +1 位作者 Huang, Wenhu Zhu, Ping 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1999年第1期22-30,共9页
In order to testify and examine the ability and correctness of an expert system for diagnosing the faults in the electrical power system of a certain kind of satellite, the authors have developed a simulated testbed a... In order to testify and examine the ability and correctness of an expert system for diagnosing the faults in the electrical power system of a certain kind of satellite, the authors have developed a simulated testbed according to the operational principle of the electrical power system. This paper takes the solar battery array as an instance to introduce the designing principle of its hardware circuits, and presents the methods to design the interface and the software program of the single-chip microprocessor system. The software scheme of the upper computer is introduced at the end of this paper. It has been proved that this simulated system could effectively achieve the complete functions coupled with the simple design by using of various mature techniques in the fields of electronic circuits, single-chip microprocessor and numerical emulation. 展开更多
关键词 Computer simulation Electric power supplies to apparatus Expert systems Failure analysis Microprocessor chips Solar cells
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CLINICAL SIMULATED EXPERIMENT ON THE SYNDROMI STANDARDS OF PULMONARY SYSTEM DISEASES
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作者 Mulin Xu Qiouqin Wang(Hubei Academy of Traditional Chinese Medicine232 Luoyu Road, Wuhan, 430074, China) 《Chinese Journal of Biomedical Engineering(English Edition)》 1994年第2期80-88,共9页
CLINICALSIMULATEDEXPERIMENTONTHESYNDROMISTANDARDSOFPULMONARYSYSTEMDISEASESMulinXuQiouqinWang(HubeiAcademyofT... CLINICALSIMULATEDEXPERIMENTONTHESYNDROMISTANDARDSOFPULMONARYSYSTEMDISEASESMulinXuQiouqinWang(HubeiAcademyofTraditionalChinese... 展开更多
关键词 : PULMONARY diseasel SYNDROMIC STANDARDS simulated EXPERIMENT
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A sediment sampling system for monitoring plume redeposition from deep-sea polymetallic nodule mining 被引量:1
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作者 Jiale Wu Jiawang Chen +8 位作者 Xinghui Tan Kaichuang Wang Jianling Zhou Zhangyong Jin Congchi Huang Yuan Lin Chunsheng Wang Junyi Yang Shiquan Lin 《International Journal of Mining Science and Technology》 2025年第11期1975-1987,共13页
The spatiotemporal characterization of plume sedimentation and microorganisms is critical for developing plume ecological monitoring model.To address the limitations of traditional methods in obtaining high-quality se... The spatiotemporal characterization of plume sedimentation and microorganisms is critical for developing plume ecological monitoring model.To address the limitations of traditional methods in obtaining high-quality sediment,a novel sampling system with 6000 m operational capability and three-month endurance was developed.It is equipped with three sediment samplers,a set of formaldehyde preservation solution injection devices.The system is controlled by a low-power,timing-triggered controllers.To investigate low-disturbance rheological mechanisms,gap controlled rheological tests were conducted to optimize the structural design of the sampling and sealing assembly.Stress-controlled shear rheological tests were employed to investigate the mechanisms governing yield stress in sediments under varying temperature conditions and boundary roughness.Additionally,the coupled Eulerian-Lagrangian(CEL)method and sediment rheological constitutive models were employed to simulate tube-soil interaction dynamics and sediment disturbance.The radial heterogeneity of sediment disturbance and friction variation of the sampling tube were revealed.The tube was completely“plugged”at a penetration depth of 261 mm,providing critical data support to the penetration depth parameters.The deep-sea pressure test and South China Sea field trials demonstrated the system’s capability to collect and preserve quantitative time-series sediment samples with high fidelity. 展开更多
关键词 Plume sedimentation Numerical simulation Rheological test Time-series preservation Low-power control
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Simulated digestive behavior of naringin microspheres and its influence on yogurt:The rheology and antioxidant activities
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作者 Hongyue Wang Tong Zhang +2 位作者 Shuhan Liu Xiangrong Zhang Baoshan Sun 《Journal of Polyphenols》 2025年第1期1-7,共7页
In this study,naringin was encapsulated in microspheres and its simulated digestive behavior in vitro was examined.Then naringin microspheres was added in yogurt to investigate the rheology and antioxidant activities.... In this study,naringin was encapsulated in microspheres and its simulated digestive behavior in vitro was examined.Then naringin microspheres was added in yogurt to investigate the rheology and antioxidant activities.The results indicated that encapsulating naringin in microspheres delayed its digestion in the stomach,allowing more release in the intestinal part.All kinds of yogurt were solid-like in nature and the addition of microspheres increased the elastic modulus and viscosity.The naringin and microspheres incorporation enhanced the total phenolic content of the yogurt to 6.7 and 8.8 mg of gallic acid equivalent/mL,respectively.All kinds of yogurt demonstrated more than 80%scavenging ability for hydroxyl radicals at 20μL whey/mL.The addition of microspheres improved the DPPH radical scavenging ability of yogurt.This study provides a new idea for the application of polyphenols in food and the development of functional yogurt. 展开更多
关键词 NARINGIN simulated digestion YOGURT RHEOLOGY antioxidant activity
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Development of an automated photolysis rates prediction system based on machine learning
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作者 Weijun Pan Sunling Gong +4 位作者 Huabing Ke Xin Li Duohong Chen Cheng Huang Danlin Song 《Journal of Environmental Sciences》 2025年第5期211-224,共14页
Based on observed meteorological elements,photolysis rates(J-values)and pollutant concentrations,an automated J-values predicting system by machine learning(J-ML)has been developed to reproduce and predict the J-value... Based on observed meteorological elements,photolysis rates(J-values)and pollutant concentrations,an automated J-values predicting system by machine learning(J-ML)has been developed to reproduce and predict the J-values of O^(1)D,NO_(2),HONO,H_(2)O_(2),HCHO,and NO_(3),which are the crucial values for the prediction of the atmospheric oxidation capacity(AOC)and secondary pollutant concentrations such as ozone(O_(3)),secondary organic aerosols(SOA).The J-ML can self-select the optimal“Model+Hyperparameters”without human interference.The evaluated results showed that the J-ML had a good performance to reproduce the J-values wheremost of the correlation(R)coefficients exceed 0.93 and the accuracy(P)values are in the range of 0.68-0.83,comparing with the J-values from observations and from the tropospheric ultraviolet and visible(TUV)radiation model in Beijing,Chengdu,Guangzhou and Shanghai,China.The hourly prediction was also well performed with R from 0.78 to 0.81 for next 3-days and from 0.69 to 0.71 for next 7-days,respectively.Compared with O_(3)concentrations by using J-values from the TUV model,an emission-driven observation-based model(e-OBM)by using the J-values from the J-ML showed a 4%-12%increase in R and 4%-30%decrease in ME,indicating that the J-ML could be used as an excellent supplement to traditional numerical models.The feature importance analysis concluded that the key influential parameter was the surface solar downwards radiation for all J-values,and the other dominant factors for all J-values were 2-m mean temperature,O_(3),total cloud cover,boundary layer height,relative humidity and surface pressure. 展开更多
关键词 J-values Automated prediction system Machine learning Short-term prediction O_(3)simulated improvement
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