The traceability system can effectively reduce the food safety risks, however, it is confronted with various problems during its implementation. In this context, the paper carries out a case study of consumers in Weif...The traceability system can effectively reduce the food safety risks, however, it is confronted with various problems during its implementation. In this context, the paper carries out a case study of consumers in Weifang, Shandong Province, and studies their willingness to pay the traceable pork with different quality information. The results indicate that, the consumers show high expectations towards the introduction of traceability system, and they tend to buy the traceable pork only with breeding and slaughter information; their behaviors of purchase are greatly influenced by the following factors: the consumers education, age, income, attention on food safety and whether there are pregnant family members, etc..展开更多
Brain functional impairment after stroke is common;however,the molecular mechanisms of post-stroke recovery remain unclear.It is well-recognized that age is the most important independent predictor of poor outcomes af...Brain functional impairment after stroke is common;however,the molecular mechanisms of post-stroke recovery remain unclear.It is well-recognized that age is the most important independent predictor of poor outcomes after stroke as older patients show poorer functional outcomes following stroke.Mounting evidence suggests that axonal regeneration and angiogenesis,the major forms of brain plasticity responsible for post-stroke recovery,diminished with advanced age.Previous studies suggest that Ras-related C3 botulinum toxin substrate(Rac)1 enhances stroke recovery as activation of Rac1 improved behavior recovery in a young mice stroke model.Here,we investigated the role of Rac1 signaling in long-term functional recovery and brain plasticity in an aged(male,18 to 22 months old C57BL/6J)brain after ischemic stroke.We found that as mice aged,Rac1 expression declined in the brain.Delayed overexpression of Rac1,using lentivirus encoding Rac1 injected day 1 after ischemic stroke,promoted cognitive(assessed using novel object recognition test)and sensorimotor(assessed using adhesive removal tests)recovery on days 14–28.This was accompanied by the increase of neurite and proliferative endothelial cells in the periinfarct zone assessed by immunostaining.In a reverse approach,pharmacological inhibition of Rac1 by intraperitoneal injection of Rac1 inhibitor NSC23766 for 14 successive days after ischemic stroke worsened the outcome with the reduction of neurite and proliferative endothelial cells.Furthermore,Rac1 inhibition reduced the activation of p21-activated kinase 1,the protein level of brain-derived neurotrophic factor,and increased the protein level of glial fibrillary acidic protein in the ischemic brain on day 28 after stroke.Our work provided insight into the mechanisms behind the diminished plasticity after cerebral ischemia in aged brains and identified Rac1 as a potential therapeutic target for improving functional recovery in the older adults after stroke.展开更多
Undercooling solidification under a magnetic field(UMF)is an effective way to tailor the microstructure and properties of Co-based alloys.In this study,by attributing to the UMF treatment,the strength−ductility trade-...Undercooling solidification under a magnetic field(UMF)is an effective way to tailor the microstructure and properties of Co-based alloys.In this study,by attributing to the UMF treatment,the strength−ductility trade-off dilemma in GH605 superalloy is successfully overcome.The UMF treatment can effectively refine the grains and increase the solid solubility,leading to the high yield strength.The main deformation mechanism in the as-forged alloy is dislocation slipping.By contrast,multiple deformation mechanisms,including stacking faults,twining,dislocation slipping,and their strong interactions are activated in the UMF-treated sample during compression deformation,which enhances the strength and ductility simultaneously.In addition,the precipitation of hard Laves phases along the grain boundaries can be obtained after UMF treatment,hindering crack propagation during compression deformation.展开更多
The noise that comes from finite element simulation often causes the model to fall into the local optimal solution and over fitting during optimization of generator.Thus,this paper proposes a Gaussian Process Regressi...The noise that comes from finite element simulation often causes the model to fall into the local optimal solution and over fitting during optimization of generator.Thus,this paper proposes a Gaussian Process Regression(GPR)model based on Conditional Likelihood Lower Bound Search(CLLBS)to optimize the design of the generator,which can filter the noise in the data and search for global optimization by combining the Conditional Likelihood Lower Bound Search method.Taking the efficiency optimization of 15 kW Permanent Magnet Synchronous Motor as an example.Firstly,this method uses the elementary effect analysis to choose the sensitive variables,combining the evolutionary algorithm to design the super Latin cube sampling plan;Then the generator-converter system is simulated by establishing a co-simulation platform to obtain data.A Gaussian process regression model combing the method of the conditional likelihood lower bound search is established,which combined the chi-square test to optimize the accuracy of the model globally.Secondly,after the model reaches the accuracy,the Pareto frontier is obtained through the NSGA-II algorithm by considering the maximum output torque as a constraint.Last,the constrained optimization is transformed into an unconstrained optimizing problem by introducing maximum constrained improvement expectation(CEI)optimization method based on the re-interpolation model,which cross-validated the optimization results of the Gaussian process regression model.The above method increase the efficiency of generator by 0.76%and 0.5%respectively;And this method can be used for rapid modeling and multi-objective optimization of generator systems.展开更多
BACKGROUND Clostridium difficile(C.difficile)infection(CDI)is a rare clinical disease caused by changes in the intestinal microenvironment,which has a variety of causes and a poor prognosis,and for which there is no s...BACKGROUND Clostridium difficile(C.difficile)infection(CDI)is a rare clinical disease caused by changes in the intestinal microenvironment,which has a variety of causes and a poor prognosis,and for which there is no standardized clinical treatment.CASE SUMMARY A patient experienced recurrent difficulty in bowel movements over the past decade.Recently,symptoms worsened within the last ten days,leading to a clinic visit due to constipation.The patient was subsequently referred to our depart-ment.Preoperatively,the patient was diagnosed with obstructed colon accom-panied by gallstones.Empirical antibiotics were administered both before and after surgery to prevent infection.On the fourth day post-surgery,symptoms of CDI emerged.Stool cultures confirmed the presence of C.difficile DNA.Treatment involved a combination of vancomycin and linezolid,resulting in the patient's successful recovery upon discharge.However,the patient failed to adhere to the prescribed medication after discharge and was discovered deceased during a follow-up two months later.CONCLUSION CDI is the leading cause of nosocomial post-operative care,with limited clinical cases and poor patient prognosis,and comprehensive clinical treatment guidelines are still lacking.This infection can be triggered by a variety of factors,including intestinal hypoxia,inappropriate antibiotic use,and bile acid circulation disorders.In patients with chronic bowel disease and related etiologies,prompt preoperative attention to possible CDI and preoperative bowel preparation is critical.Adequate and prolonged medication should be maintained in the treatment of CDI to prevent recurrence of the disease.展开更多
Ischemic stroke can cause blood-brain barrier(BBB)injury,which worsens brain damage induced by stroke.Abnormal expression of tight junction proteins in endothelial cells(ECs)can increase intracellular space and BBB le...Ischemic stroke can cause blood-brain barrier(BBB)injury,which worsens brain damage induced by stroke.Abnormal expression of tight junction proteins in endothelial cells(ECs)can increase intracellular space and BBB leakage.Selective inhibition of mitogen-activated protein kinase,the negative regulatory substrate of mitogen-activated protein kinase phosphatase(MKP)-1,improves tight junction protein function in ECs,and genetic deletion of MKP-1 aggravates ischemic brain injury.However,whether the latter affects BBB integrity,and the cell type-specific mechanism underlying this process,remain unclear.In this study,we established an adult male mouse model of ischemic stroke by occluding the middle cerebral artery for 60 minutes and overexpressed MKP-1 in ECs on the injured side via lentiviral transfection before stroke.We found that overexpression of MKP-1 in ECs reduced infarct volume,reduced the level of inflammatory factors interleukin-1β,interleukin-6,and chemokine C-C motif ligand-2,inhibited vascular injury,and promoted the recovery of sensorimotor and memory/cognitive function.Overexpression of MKP-1 in ECs also inhibited the activation of cerebral ischemia-induced extracellular signal-regulated kinase(ERK)1/2 and the downregulation of occludin expression.Finally,to investigate the mechanism by which MKP-1 exerted these functions in ECs,we established an ischemic stroke model in vitro by depriving the primary endothelial cell of oxygen and glucose,and pharmacologically inhibited the activity of MKP-1 and ERK1/2.Our findings suggest that MKP-1 inhibition aggravates oxygen and glucose deprivation-induced cell death,cell monolayer leakage,and downregulation of occludin expression,and that inhibiting ERK1/2 can reverse these effects.In addition,co-inhibition of MKP-1 and ERK1/2 exhibited similar effects to inhibition of ERK1/2.These findings suggest that overexpression of MKP-1 in ECs can prevent ischemia-induced occludin downregulation and cell death via deactivating ERK1/2,thereby protecting the integrity of BBB,alleviating brain injury,and improving post-stroke prognosis.展开更多
Cortical spreading depression (CSD) is a transient synaptic excitation, followed by depression, which can propagate slowly across cortex, subcortex and retina. CSD is implicated in migraine with aura and may lead to m...Cortical spreading depression (CSD) is a transient synaptic excitation, followed by depression, which can propagate slowly across cortex, subcortex and retina. CSD is implicated in migraine with aura and may lead to migraine pain. CSD can be suppressed by inhibition of both NR2A and NR2B containing N-methyl-D-aspartic acid (NMDA) receptors. However, whether there is a synergistic effect of co-inhibition of NR2A and NR2B containing receptors on CSD remains unknown. In this study, an efficient in vitro model of migraine with intrinsic optical imaging approach was applied to address this role of co-activation of both NR2A and NR2B in CSD. The results showed that co-application of NVP-AAM077, a drug selectively targeting for NR2A and Ro 25-6981, a drug selectively targeting for NR2B containing receptors, showed synergistic inhibitory effects on propagation rate and the magnitude of CSD in a concentration dependent manner in chick retina. Inhibition of CSD propagation was also observed by a clinical acceptable drug that antagonizes both NR2A and NR2B containing receptors, memantine, at 10 μM. These data suggest that combinational use of antagonists selectively targeting NR2A and NR2B containing receptors could be a useful strategy for preventative treatment of migraine with improved efficacy with potential alleviated side effects.展开更多
Chronic hepatitis B virus(HBV)infection can lead to advanced liver pathology.Here,we establish a transgenic murine model expressing a basic core promoter(BCP)-mutated HBV genome.Unlike previous studies on the wild-typ...Chronic hepatitis B virus(HBV)infection can lead to advanced liver pathology.Here,we establish a transgenic murine model expressing a basic core promoter(BCP)-mutated HBV genome.Unlike previous studies on the wild-type virus,the BCP-mutated HBV transgenic mice manifest chronic liver injury that culminates in cirrhosis and tumor development with age.Notably,agonistic anti-Fas treatment induces fulminant hepatitis in these mice even at a negligible dose.As the BCP mutant exhibits a striking increase in HBV core protein(HBc)expression,we posit that HBc is actively involved in hepatocellular injury.Accordingly,HBc interferes with Fis1-stimulated mitochondrial recruitment of Tre-2/Bub2/Cdc16 domain family member 15(TBC1D15).HBc may also inhibit multiple Rab GTPase-activating proteins,including Rab7-specific TBC1D15 and TBC1D5,by binding to their conserved catalytic domain.In cells under mitochondrial stress,HBc thus perturbs mitochondrial dynamics and prevents the recycling of damaged mitochondria.Moreover,sustained HBc expression causes lysosomal consumption via Rab7 hyperactivation,which further hampers late-stage autophagy and substantially increases apoptotic cell death.Finally,we show that adenovirally expressed HBc in a mouse model is directly cytopathic and causes profound liver injury,independent of antigen-specific immune clearance.These findings reveal an unexpected cytopathic role of HBc,making it a pivotal target for HBV-associated liver disease treatment.The BCP-mutated HBV transgenic mice also provide a valuable model for understanding chronic hepatitis B progression and for the assessment of therapeutic strategies.展开更多
Buildings contribute to almost 30%of total energy consumption worldwide.Developing building energy modeling programs is of great significance for lifecycle building performance assessment and optimization.Advances in ...Buildings contribute to almost 30%of total energy consumption worldwide.Developing building energy modeling programs is of great significance for lifecycle building performance assessment and optimization.Advances in novel building technologies,the requirements of high-performance computation,and the demands for multi-objective models have brought new challenges for building energy modeling software and platforms.To meet the increasing simulation demands,DeST 3.0,a new-generation building performance simulation platform,was developed and released.The structure of DeST 3.0 incorporates four simulation engines,including building analysis and simulation(BAS)engine,HVAC system engine,combined plant simulation(CPS)engine,and energy system(ES)engine,connected by air loop and water loop balancing iterations.DeST 3.0 offers numerous new simulation features,such as advanced simulation modules for building envelopes,occupant behavior and energy systems,cross-platform and compatible simulation kernel,FMI/FMU-based co-simulation functionalities,and high-performance parallel simulation architecture.DeST 3.0 has been thoroughly evaluated and validated using code verification,inter-program comparison,and case-study calibration.DeST 3.0 has been applied in various aspects throughout the building lifecycle,supporting building design,operation,retrofit analysis,code appliance,technology adaptability evaluation as well as research and education.The new generation building simulation platform DeST 3.0 provides an efficient tool and comprehensive simulation platform for lifecycle building performance analysis and optimization.展开更多
Systematic understanding on the magnetic field intensity dependent microstructure evolution and re-crystallization behavior in a Co-B eutectic alloy under a constant undercooling(ΔT≈100 K)were carried out.Absent of ...Systematic understanding on the magnetic field intensity dependent microstructure evolution and re-crystallization behavior in a Co-B eutectic alloy under a constant undercooling(ΔT≈100 K)were carried out.Absent of the magnetic field,the comparable size of divorced FCC-Co and Co_(3)B eutectic ellipsoidal grains coexist with a few regular lamellas.When the magnetic field is less than 15 T,the elongated primary FCC-Co dendrites parallel to the magnetic field with the dispersed FCC-Co nano-particles em-bedded within the Co_(3)B matrix occupy the inter-dendrite regions.Once the magnetic field increases to 20 T,the FCC-Co/Co_(2)B anomalous eutectic colonies dominate.The formation mechanism of Co_(2)B phase is discussed from several aspects of the competitive nucleation,the chemical redistribution induced by the thermomagnetic-induced convection and magnetic dipole interaction,and the strain-induced trans-formation.Furthermore,the application of magnetic field is found to promote recrystallization,proved by the lower density of misorientation,the appearance of FCC-Co annealed twins and more Co_(3)B sub-grains.This work could further enrich our knowledge about the magnetic-dependent microstructure evolution and recrystallization process in the undercooled Co-B system and provide guidance for controlling the microstructures and properties under extreme conditions.展开更多
Coagulation–ultrafiltration(C–UF) is widely used for surface water treatment. With the removal of pollutants, the characteristics of organic matter change and affect the final treatment efficiency and the developmen...Coagulation–ultrafiltration(C–UF) is widely used for surface water treatment. With the removal of pollutants, the characteristics of organic matter change and affect the final treatment efficiency and the development of membrane fouling. In this study, we built a dynamic C–UF set-up to carry out the treatment of micro-polluted surface water, to investigate the characteristics of dissolved organic matter from different units. The influences of poly aluminum chloride and poly dimethyldiallylammonium chloride(PDMDAAC) on removal efficiency and membrane fouling were also investigated. Results showed that the dosage of PDMDAAC evidently increased the UV254 and dissolved organic carbon removal efficiencies,and thereby alleviated membrane fouling in the C–UF process. Most hydrophobic bases(HoB)and hydrophobic neutral fractions could be removed by coagulation. Similarly, UF was good at removing HoB compared to hydrophilic substances(HiS) and hydrophobic acid(HoA)fractions. HiS and HoA fractions with low molecule weight accumulated on the surface of the membrane, causing the increase of transmembrane pressure(TMP). Membrane fouling was mainly caused by a removable cake layer, and mechanical cleaning was an efficient way to decrease the TMP.展开更多
The aim of this study was to investigate the effects of one kind of food industry effluent, cassava stillage and its anaerobic fermentation liquid, on biological nutrient removal (BNR) from municipal wastewater in a...The aim of this study was to investigate the effects of one kind of food industry effluent, cassava stillage and its anaerobic fermentation liquid, on biological nutrient removal (BNR) from municipal wastewater in anaerobic- anoxic-aerobic sequencing batch reactors (SBRs). Experiments were carried out with cassava stillage supernatant and its anaerobic fermentation liquid, and one pure compound (sodium acetate) served as an external carbon source. Cyclic studies indicated that the cassava by-products not only affected the transformation of nitrogen, phosphorus, poly-13-hydroxyalkanoates (PHAs), and glycogen in the BNR process, but also resulted in higher removal efficiencies for phosphorus and nitrogen compared with sodium acetate. Furthermore, assays for phosphorus accumulating or- ganisms (PAOs) and denitrifying phosphorus accumulating organisms (DPAOs) demonstrated that the proportion of DPAOs to PAOs reached 62.6% (Day 86) and 61.8% (Day 65) when using cassava stillage and its anaerobic fer- mentation liquid, respectively, as the external carbon source. In addition, the nitrate utilization rates (NURs) of the cassava by-products were in the range of 5.49-5.99 g N/(kg MLVSS.h) (MLVSS is mixed liquor volatile suspended solids) and 6.63-6.81 g N/(kg MLVSS.h), respectively. The improvement in BNR performance and the reduction in the amount of cassava stillage to be treated in-situ make cassava stillage and its anaerobic fermentation liquid attractive alternatives to sodium acetate as external carbon sources for BNR processes.展开更多
The structure transition inside the Co-81.5at.%B alloy liquid has been studied by an in-situ magnetization measurement.A crossover was observed on the 1/M-T curve during the overheating process,indicating that a liqui...The structure transition inside the Co-81.5at.%B alloy liquid has been studied by an in-situ magnetization measurement.A crossover was observed on the 1/M-T curve during the overheating process,indicating that a liquid-liquid structure transition(LLST)took place in the melt.Based on this information,the effects of LLST on the solidification behavior,microstructure and tribology property were investigated experimentally.The sample solidified with the LLST exhibits significantly different solidification behaviors,i.e.,the nucleation undercooling and the recalescence extent are conspicuously enlarged,and the solidification time is shortened.As a result,the microstructure is effectively refined and homogenized,and the hardness and wear resistance are significantly enhanced.The present work might be helpful for not only theoretically understanding the influence of LLST on the solidification behavior but also providing an alternative approach to tailor the microstructure and properties.展开更多
Plants have a hierarchical circadian structure comprising multiple tissue-specific oscillators that operate at different speeds and regulate the expression of distinct sets of genes in different organs.However,the ide...Plants have a hierarchical circadian structure comprising multiple tissue-specific oscillators that operate at different speeds and regulate the expression of distinct sets of genes in different organs.However,the identity of the genes differentially regulated by the circadian clock in different organs,such as roots,and how their oscillations create functional specialization remain unclear.Here,we profiled the diurnal and circadian landscapes of the shoots and roots of Medicago truncatula and identified the conserved regulatory sequences contributing to transcriptome oscillations in each organ.We found that the light-dark cycles strongly affect the global transcriptome oscillation in roots,and many clock genes oscillate only in shoots.Moreover,many key genes involved in nitrogen fixation are regulated by circadian rhythms.Surprisingly,the root clock runs faster than the shoot clock,which is contrary to the hierarchical circadian structure showing a slow-paced root clock in both detached and intact Arabidopsis thaliana(L.)Heynh.roots.Our result provides important clues about the species-specific circadian regulatory mechanism,which is often overlooked,and possibly coordinates the timing between shoots and roots independent of the current prevailing model.展开更多
While there have been multiple recent reports in the literature focusing on the effects of magnetic field on the phase transformation behaviors,the research conducted with an ultra-high magnetic field greater than 20 ...While there have been multiple recent reports in the literature focusing on the effects of magnetic field on the phase transformation behaviors,the research conducted with an ultra-high magnetic field greater than 20 T is still preliminary.In the current study,the structure evolution of Co-B alloys are experimentally studied with undercooling.The effects of a 25 T magnetic field on the solidification behavior and the subsequent solid-state phase transformation behavior have been investigated.The 25 T magnetic field is confirmed to have little effect on the homogeneous nucleation,but have some influence on the heterogeneous nucleation of Co_(3) B and Co_(23)B6 phases by modifying the wetting angleθ.The decomposition of Co_(23)B6 phase in the subsequent cooling process can be effectively suppressed by applying the 25 T magnetic field.The present work might be helpful for not only theoretically understanding the influence of ultra-high magnetic field on the phase transformation behaviors but a potential technology of field-manipulation of magnetic materials.展开更多
The rapid development of wearable,highly integrated,and flexible electronics has stimulated great demand for on-chip and miniaturized energy storage devices.By virtue of their high power density and long cycle life,mi...The rapid development of wearable,highly integrated,and flexible electronics has stimulated great demand for on-chip and miniaturized energy storage devices.By virtue of their high power density and long cycle life,micro-supercapacitors(MSCs),especially those with interdigital structures,have attracted considerable attention.In recent years,tremendous theoretical and experimental explorations have been carried out on the structures and electrode materials of MSCs,aiming to obtain better mechanical and electrochemical properties.The high-performance MSCs can be used in many fields,such as energy storage and medical assistant examination.Here,this review focuses on the recent progress of advanced MSCs in fabrication strategies,structural design,electrode materials design and function,and integrated applications,where typical examples are highlighted and analyzed.Furthermore,the current challenges and future development directions of advanced MSCs are also discussed.展开更多
基金Supported by the Youth Project for Humanities and Social Sciences of Ministry of Education in 2012(12YJC630326 and 12XJJC790003)
文摘The traceability system can effectively reduce the food safety risks, however, it is confronted with various problems during its implementation. In this context, the paper carries out a case study of consumers in Weifang, Shandong Province, and studies their willingness to pay the traceable pork with different quality information. The results indicate that, the consumers show high expectations towards the introduction of traceability system, and they tend to buy the traceable pork only with breeding and slaughter information; their behaviors of purchase are greatly influenced by the following factors: the consumers education, age, income, attention on food safety and whether there are pregnant family members, etc..
基金supported by NIH grants RF1 AG069466(to JL and LDM),R01 NS099628(to JL),and AG069466(to JL and LDM)the American Heart Association award 20POST35180172(to FB)。
文摘Brain functional impairment after stroke is common;however,the molecular mechanisms of post-stroke recovery remain unclear.It is well-recognized that age is the most important independent predictor of poor outcomes after stroke as older patients show poorer functional outcomes following stroke.Mounting evidence suggests that axonal regeneration and angiogenesis,the major forms of brain plasticity responsible for post-stroke recovery,diminished with advanced age.Previous studies suggest that Ras-related C3 botulinum toxin substrate(Rac)1 enhances stroke recovery as activation of Rac1 improved behavior recovery in a young mice stroke model.Here,we investigated the role of Rac1 signaling in long-term functional recovery and brain plasticity in an aged(male,18 to 22 months old C57BL/6J)brain after ischemic stroke.We found that as mice aged,Rac1 expression declined in the brain.Delayed overexpression of Rac1,using lentivirus encoding Rac1 injected day 1 after ischemic stroke,promoted cognitive(assessed using novel object recognition test)and sensorimotor(assessed using adhesive removal tests)recovery on days 14–28.This was accompanied by the increase of neurite and proliferative endothelial cells in the periinfarct zone assessed by immunostaining.In a reverse approach,pharmacological inhibition of Rac1 by intraperitoneal injection of Rac1 inhibitor NSC23766 for 14 successive days after ischemic stroke worsened the outcome with the reduction of neurite and proliferative endothelial cells.Furthermore,Rac1 inhibition reduced the activation of p21-activated kinase 1,the protein level of brain-derived neurotrophic factor,and increased the protein level of glial fibrillary acidic protein in the ischemic brain on day 28 after stroke.Our work provided insight into the mechanisms behind the diminished plasticity after cerebral ischemia in aged brains and identified Rac1 as a potential therapeutic target for improving functional recovery in the older adults after stroke.
基金the fund of National Key Laboratory for Precision Hot Processing of Metals,China(No.6142909200104)State Key Laboratory of Solidification Processing(NPU),China(No.2022-TS-08)National Training Program of Innovation and Entrepreneurship for Undergraduates.We thank Dr.ZHENG from ZKKF(Beijing)Science&Technology Company for supporting the characterization of the materials.
文摘Undercooling solidification under a magnetic field(UMF)is an effective way to tailor the microstructure and properties of Co-based alloys.In this study,by attributing to the UMF treatment,the strength−ductility trade-off dilemma in GH605 superalloy is successfully overcome.The UMF treatment can effectively refine the grains and increase the solid solubility,leading to the high yield strength.The main deformation mechanism in the as-forged alloy is dislocation slipping.By contrast,multiple deformation mechanisms,including stacking faults,twining,dislocation slipping,and their strong interactions are activated in the UMF-treated sample during compression deformation,which enhances the strength and ductility simultaneously.In addition,the precipitation of hard Laves phases along the grain boundaries can be obtained after UMF treatment,hindering crack propagation during compression deformation.
基金supported in part by the National Key Research and Development Program of China(2019YFB1503700)the Hunan Natural Science Foundation-Science and Education Joint Project(2019JJ70063)。
文摘The noise that comes from finite element simulation often causes the model to fall into the local optimal solution and over fitting during optimization of generator.Thus,this paper proposes a Gaussian Process Regression(GPR)model based on Conditional Likelihood Lower Bound Search(CLLBS)to optimize the design of the generator,which can filter the noise in the data and search for global optimization by combining the Conditional Likelihood Lower Bound Search method.Taking the efficiency optimization of 15 kW Permanent Magnet Synchronous Motor as an example.Firstly,this method uses the elementary effect analysis to choose the sensitive variables,combining the evolutionary algorithm to design the super Latin cube sampling plan;Then the generator-converter system is simulated by establishing a co-simulation platform to obtain data.A Gaussian process regression model combing the method of the conditional likelihood lower bound search is established,which combined the chi-square test to optimize the accuracy of the model globally.Secondly,after the model reaches the accuracy,the Pareto frontier is obtained through the NSGA-II algorithm by considering the maximum output torque as a constraint.Last,the constrained optimization is transformed into an unconstrained optimizing problem by introducing maximum constrained improvement expectation(CEI)optimization method based on the re-interpolation model,which cross-validated the optimization results of the Gaussian process regression model.The above method increase the efficiency of generator by 0.76%and 0.5%respectively;And this method can be used for rapid modeling and multi-objective optimization of generator systems.
文摘BACKGROUND Clostridium difficile(C.difficile)infection(CDI)is a rare clinical disease caused by changes in the intestinal microenvironment,which has a variety of causes and a poor prognosis,and for which there is no standardized clinical treatment.CASE SUMMARY A patient experienced recurrent difficulty in bowel movements over the past decade.Recently,symptoms worsened within the last ten days,leading to a clinic visit due to constipation.The patient was subsequently referred to our depart-ment.Preoperatively,the patient was diagnosed with obstructed colon accom-panied by gallstones.Empirical antibiotics were administered both before and after surgery to prevent infection.On the fourth day post-surgery,symptoms of CDI emerged.Stool cultures confirmed the presence of C.difficile DNA.Treatment involved a combination of vancomycin and linezolid,resulting in the patient's successful recovery upon discharge.However,the patient failed to adhere to the prescribed medication after discharge and was discovered deceased during a follow-up two months later.CONCLUSION CDI is the leading cause of nosocomial post-operative care,with limited clinical cases and poor patient prognosis,and comprehensive clinical treatment guidelines are still lacking.This infection can be triggered by a variety of factors,including intestinal hypoxia,inappropriate antibiotic use,and bile acid circulation disorders.In patients with chronic bowel disease and related etiologies,prompt preoperative attention to possible CDI and preoperative bowel preparation is critical.Adequate and prolonged medication should be maintained in the treatment of CDI to prevent recurrence of the disease.
基金supported by Research Start-up Funding of Shenzhen Traditional Chinese Medicine Hospital,No.2021-07(to FB)Sanming Project of Medicine in Shenzhen,No.SZZYSM 202111011(to XDQ and FB)+1 种基金Key Discipline Established by Zhejiang Province,Jiaxing City Jointly-Pain Medicine,No.2019-ss-ttyx(to LSX)Jiaxing Key Laboratory of Neurology and Pain Medicine,No.[2014]81(to LSX)。
文摘Ischemic stroke can cause blood-brain barrier(BBB)injury,which worsens brain damage induced by stroke.Abnormal expression of tight junction proteins in endothelial cells(ECs)can increase intracellular space and BBB leakage.Selective inhibition of mitogen-activated protein kinase,the negative regulatory substrate of mitogen-activated protein kinase phosphatase(MKP)-1,improves tight junction protein function in ECs,and genetic deletion of MKP-1 aggravates ischemic brain injury.However,whether the latter affects BBB integrity,and the cell type-specific mechanism underlying this process,remain unclear.In this study,we established an adult male mouse model of ischemic stroke by occluding the middle cerebral artery for 60 minutes and overexpressed MKP-1 in ECs on the injured side via lentiviral transfection before stroke.We found that overexpression of MKP-1 in ECs reduced infarct volume,reduced the level of inflammatory factors interleukin-1β,interleukin-6,and chemokine C-C motif ligand-2,inhibited vascular injury,and promoted the recovery of sensorimotor and memory/cognitive function.Overexpression of MKP-1 in ECs also inhibited the activation of cerebral ischemia-induced extracellular signal-regulated kinase(ERK)1/2 and the downregulation of occludin expression.Finally,to investigate the mechanism by which MKP-1 exerted these functions in ECs,we established an ischemic stroke model in vitro by depriving the primary endothelial cell of oxygen and glucose,and pharmacologically inhibited the activity of MKP-1 and ERK1/2.Our findings suggest that MKP-1 inhibition aggravates oxygen and glucose deprivation-induced cell death,cell monolayer leakage,and downregulation of occludin expression,and that inhibiting ERK1/2 can reverse these effects.In addition,co-inhibition of MKP-1 and ERK1/2 exhibited similar effects to inhibition of ERK1/2.These findings suggest that overexpression of MKP-1 in ECs can prevent ischemia-induced occludin downregulation and cell death via deactivating ERK1/2,thereby protecting the integrity of BBB,alleviating brain injury,and improving post-stroke prognosis.
文摘Cortical spreading depression (CSD) is a transient synaptic excitation, followed by depression, which can propagate slowly across cortex, subcortex and retina. CSD is implicated in migraine with aura and may lead to migraine pain. CSD can be suppressed by inhibition of both NR2A and NR2B containing N-methyl-D-aspartic acid (NMDA) receptors. However, whether there is a synergistic effect of co-inhibition of NR2A and NR2B containing receptors on CSD remains unknown. In this study, an efficient in vitro model of migraine with intrinsic optical imaging approach was applied to address this role of co-activation of both NR2A and NR2B in CSD. The results showed that co-application of NVP-AAM077, a drug selectively targeting for NR2A and Ro 25-6981, a drug selectively targeting for NR2B containing receptors, showed synergistic inhibitory effects on propagation rate and the magnitude of CSD in a concentration dependent manner in chick retina. Inhibition of CSD propagation was also observed by a clinical acceptable drug that antagonizes both NR2A and NR2B containing receptors, memantine, at 10 μM. These data suggest that combinational use of antagonists selectively targeting NR2A and NR2B containing receptors could be a useful strategy for preventative treatment of migraine with improved efficacy with potential alleviated side effects.
基金supported by the Shanghai Municipal Science and Technology Major Project(ZD2021CY001)the National Natural Science Foundation of China(82372233,82072279,81871647,and 82205055)the Innovation Fund for Medical Sciences from Chinese Academy of Medical Sciences(2019-I2M-5-040).
文摘Chronic hepatitis B virus(HBV)infection can lead to advanced liver pathology.Here,we establish a transgenic murine model expressing a basic core promoter(BCP)-mutated HBV genome.Unlike previous studies on the wild-type virus,the BCP-mutated HBV transgenic mice manifest chronic liver injury that culminates in cirrhosis and tumor development with age.Notably,agonistic anti-Fas treatment induces fulminant hepatitis in these mice even at a negligible dose.As the BCP mutant exhibits a striking increase in HBV core protein(HBc)expression,we posit that HBc is actively involved in hepatocellular injury.Accordingly,HBc interferes with Fis1-stimulated mitochondrial recruitment of Tre-2/Bub2/Cdc16 domain family member 15(TBC1D15).HBc may also inhibit multiple Rab GTPase-activating proteins,including Rab7-specific TBC1D15 and TBC1D5,by binding to their conserved catalytic domain.In cells under mitochondrial stress,HBc thus perturbs mitochondrial dynamics and prevents the recycling of damaged mitochondria.Moreover,sustained HBc expression causes lysosomal consumption via Rab7 hyperactivation,which further hampers late-stage autophagy and substantially increases apoptotic cell death.Finally,we show that adenovirally expressed HBc in a mouse model is directly cytopathic and causes profound liver injury,independent of antigen-specific immune clearance.These findings reveal an unexpected cytopathic role of HBc,making it a pivotal target for HBV-associated liver disease treatment.The BCP-mutated HBV transgenic mice also provide a valuable model for understanding chronic hepatitis B progression and for the assessment of therapeutic strategies.
基金supported by the“13th Five-Year”National Key R&D Program of China(No.2017YFC0702200)。
文摘Buildings contribute to almost 30%of total energy consumption worldwide.Developing building energy modeling programs is of great significance for lifecycle building performance assessment and optimization.Advances in novel building technologies,the requirements of high-performance computation,and the demands for multi-objective models have brought new challenges for building energy modeling software and platforms.To meet the increasing simulation demands,DeST 3.0,a new-generation building performance simulation platform,was developed and released.The structure of DeST 3.0 incorporates four simulation engines,including building analysis and simulation(BAS)engine,HVAC system engine,combined plant simulation(CPS)engine,and energy system(ES)engine,connected by air loop and water loop balancing iterations.DeST 3.0 offers numerous new simulation features,such as advanced simulation modules for building envelopes,occupant behavior and energy systems,cross-platform and compatible simulation kernel,FMI/FMU-based co-simulation functionalities,and high-performance parallel simulation architecture.DeST 3.0 has been thoroughly evaluated and validated using code verification,inter-program comparison,and case-study calibration.DeST 3.0 has been applied in various aspects throughout the building lifecycle,supporting building design,operation,retrofit analysis,code appliance,technology adaptability evaluation as well as research and education.The new generation building simulation platform DeST 3.0 provides an efficient tool and comprehensive simulation platform for lifecycle building performance analysis and optimization.
基金This work was financially supported by the National Natu-ral Science Foundation of China(Nos.52104386 and 52127807)Shanghai Sailing Program,Xi’an Association for Science and Tech-nology Young Talents Lifting Program,and the State Key Laboratory of Solidification Processing(NPU),China(No.2022-TS-08).We acknowledge the support of the LNCMI-CNRS,member of the Euro-pean Magnetic Field Laboratory(EMFL).We also thank Dr.Zheng from ZKKF(Beijing)Science&Technology Company for supporting the characterization of the materials.
文摘Systematic understanding on the magnetic field intensity dependent microstructure evolution and re-crystallization behavior in a Co-B eutectic alloy under a constant undercooling(ΔT≈100 K)were carried out.Absent of the magnetic field,the comparable size of divorced FCC-Co and Co_(3)B eutectic ellipsoidal grains coexist with a few regular lamellas.When the magnetic field is less than 15 T,the elongated primary FCC-Co dendrites parallel to the magnetic field with the dispersed FCC-Co nano-particles em-bedded within the Co_(3)B matrix occupy the inter-dendrite regions.Once the magnetic field increases to 20 T,the FCC-Co/Co_(2)B anomalous eutectic colonies dominate.The formation mechanism of Co_(2)B phase is discussed from several aspects of the competitive nucleation,the chemical redistribution induced by the thermomagnetic-induced convection and magnetic dipole interaction,and the strain-induced trans-formation.Furthermore,the application of magnetic field is found to promote recrystallization,proved by the lower density of misorientation,the appearance of FCC-Co annealed twins and more Co_(3)B sub-grains.This work could further enrich our knowledge about the magnetic-dependent microstructure evolution and recrystallization process in the undercooled Co-B system and provide guidance for controlling the microstructures and properties under extreme conditions.
基金supported by the National Natural Science Foundation of China (No.51678349)the Tai Shan Scholar Foundation (No.ts201511003)
文摘Coagulation–ultrafiltration(C–UF) is widely used for surface water treatment. With the removal of pollutants, the characteristics of organic matter change and affect the final treatment efficiency and the development of membrane fouling. In this study, we built a dynamic C–UF set-up to carry out the treatment of micro-polluted surface water, to investigate the characteristics of dissolved organic matter from different units. The influences of poly aluminum chloride and poly dimethyldiallylammonium chloride(PDMDAAC) on removal efficiency and membrane fouling were also investigated. Results showed that the dosage of PDMDAAC evidently increased the UV254 and dissolved organic carbon removal efficiencies,and thereby alleviated membrane fouling in the C–UF process. Most hydrophobic bases(HoB)and hydrophobic neutral fractions could be removed by coagulation. Similarly, UF was good at removing HoB compared to hydrophilic substances(HiS) and hydrophobic acid(HoA)fractions. HiS and HoA fractions with low molecule weight accumulated on the surface of the membrane, causing the increase of transmembrane pressure(TMP). Membrane fouling was mainly caused by a removable cake layer, and mechanical cleaning was an efficient way to decrease the TMP.
基金supported by the National Water Pollution Control and Management of Major Special Science and Technology Foundation(No.2011ZX07303-001),China
文摘The aim of this study was to investigate the effects of one kind of food industry effluent, cassava stillage and its anaerobic fermentation liquid, on biological nutrient removal (BNR) from municipal wastewater in anaerobic- anoxic-aerobic sequencing batch reactors (SBRs). Experiments were carried out with cassava stillage supernatant and its anaerobic fermentation liquid, and one pure compound (sodium acetate) served as an external carbon source. Cyclic studies indicated that the cassava by-products not only affected the transformation of nitrogen, phosphorus, poly-13-hydroxyalkanoates (PHAs), and glycogen in the BNR process, but also resulted in higher removal efficiencies for phosphorus and nitrogen compared with sodium acetate. Furthermore, assays for phosphorus accumulating or- ganisms (PAOs) and denitrifying phosphorus accumulating organisms (DPAOs) demonstrated that the proportion of DPAOs to PAOs reached 62.6% (Day 86) and 61.8% (Day 65) when using cassava stillage and its anaerobic fer- mentation liquid, respectively, as the external carbon source. In addition, the nitrate utilization rates (NURs) of the cassava by-products were in the range of 5.49-5.99 g N/(kg MLVSS.h) (MLVSS is mixed liquor volatile suspended solids) and 6.63-6.81 g N/(kg MLVSS.h), respectively. The improvement in BNR performance and the reduction in the amount of cassava stillage to be treated in-situ make cassava stillage and its anaerobic fermentation liquid attractive alternatives to sodium acetate as external carbon sources for BNR processes.
基金financially supported by the fund of National Key Laboratory for Precision Hot Processing of Metals(No.6142909200104)Shanghai Sailing Program+2 种基金National Training Program of Innovation and Entrepreneurship for Undergraduates(No.S202010699137)Natural Science Foundation of China(Nos.51690164 and 51801161)the Fundamental Research Funds for the Central Universities。
文摘The structure transition inside the Co-81.5at.%B alloy liquid has been studied by an in-situ magnetization measurement.A crossover was observed on the 1/M-T curve during the overheating process,indicating that a liquid-liquid structure transition(LLST)took place in the melt.Based on this information,the effects of LLST on the solidification behavior,microstructure and tribology property were investigated experimentally.The sample solidified with the LLST exhibits significantly different solidification behaviors,i.e.,the nucleation undercooling and the recalescence extent are conspicuously enlarged,and the solidification time is shortened.As a result,the microstructure is effectively refined and homogenized,and the hardness and wear resistance are significantly enhanced.The present work might be helpful for not only theoretically understanding the influence of LLST on the solidification behavior but also providing an alternative approach to tailor the microstructure and properties.
基金Research in the laboratory of WH is supported by the National Natural Science Foundation of China(31700236)NSFC-Guangdong Joint Fund(U170120015)+1 种基金the Research Team Project from the Natural Science Foundation of Guangdong Province(2016A030312009)the Natural Science Foundation of Guangdong Province(2019A1515012009).
文摘Plants have a hierarchical circadian structure comprising multiple tissue-specific oscillators that operate at different speeds and regulate the expression of distinct sets of genes in different organs.However,the identity of the genes differentially regulated by the circadian clock in different organs,such as roots,and how their oscillations create functional specialization remain unclear.Here,we profiled the diurnal and circadian landscapes of the shoots and roots of Medicago truncatula and identified the conserved regulatory sequences contributing to transcriptome oscillations in each organ.We found that the light-dark cycles strongly affect the global transcriptome oscillation in roots,and many clock genes oscillate only in shoots.Moreover,many key genes involved in nitrogen fixation are regulated by circadian rhythms.Surprisingly,the root clock runs faster than the shoot clock,which is contrary to the hierarchical circadian structure showing a slow-paced root clock in both detached and intact Arabidopsis thaliana(L.)Heynh.roots.Our result provides important clues about the species-specific circadian regulatory mechanism,which is often overlooked,and possibly coordinates the timing between shoots and roots independent of the current prevailing model.
基金supported by the National Natural Science Foundation of China(No.51690164)the fund of National Key Laboratory for Precision Hot Processing of Metals(6142909200104)+2 种基金National Training Program of Innovation and Entrepreneurship for Undergraduates(S202010699137)the Fundamental Research Funds for the Central Universitiesthe support of the LNCMI-CNRS。
文摘While there have been multiple recent reports in the literature focusing on the effects of magnetic field on the phase transformation behaviors,the research conducted with an ultra-high magnetic field greater than 20 T is still preliminary.In the current study,the structure evolution of Co-B alloys are experimentally studied with undercooling.The effects of a 25 T magnetic field on the solidification behavior and the subsequent solid-state phase transformation behavior have been investigated.The 25 T magnetic field is confirmed to have little effect on the homogeneous nucleation,but have some influence on the heterogeneous nucleation of Co_(3) B and Co_(23)B6 phases by modifying the wetting angleθ.The decomposition of Co_(23)B6 phase in the subsequent cooling process can be effectively suppressed by applying the 25 T magnetic field.The present work might be helpful for not only theoretically understanding the influence of ultra-high magnetic field on the phase transformation behaviors but a potential technology of field-manipulation of magnetic materials.
基金The authors acknowledge the financial supports by National Natural Science Foundation of China(Grant No.51902265)Fundamental Research Funds for the Central Universities,Key Research and Development Program of Shaanxi(Program No.2020KWZ-001),and Project for graduate Innovation team of Northwestern Polytechnical University.
文摘The rapid development of wearable,highly integrated,and flexible electronics has stimulated great demand for on-chip and miniaturized energy storage devices.By virtue of their high power density and long cycle life,micro-supercapacitors(MSCs),especially those with interdigital structures,have attracted considerable attention.In recent years,tremendous theoretical and experimental explorations have been carried out on the structures and electrode materials of MSCs,aiming to obtain better mechanical and electrochemical properties.The high-performance MSCs can be used in many fields,such as energy storage and medical assistant examination.Here,this review focuses on the recent progress of advanced MSCs in fabrication strategies,structural design,electrode materials design and function,and integrated applications,where typical examples are highlighted and analyzed.Furthermore,the current challenges and future development directions of advanced MSCs are also discussed.