In order to identify the resistant gene of rice false smut in rice, a recombi- nant inbred line （RILs） population with 157 lines derived from an inter-subspecies cross of Daguandao/IR28 by the single seed descent me...In order to identify the resistant gene of rice false smut in rice, a recombi- nant inbred line （RILs） population with 157 lines derived from an inter-subspecies cross of Daguandao/IR28 by the single seed descent method was used to detect quantitative trait loci （QTLs） conferring resistance to strain Pi-1 of rice false smut caused by Usti/aginoiclea virens （Cooke） Takahashi in 2012 and 2013. The disease rate indexes of the two parents and 157 RILs caused by the strain Pi-1 of rice false smut were scored and the QTLs for rice false smut resistance were detected accordingly by QTL Cartographer software. Seven QTLs controlling false smut re- sistance were detected on chromosomes 2, 7, 8, 11 and 12, respectively, with the phenotypic variance of 8.5%-17.2%. There were four QTLs detected in 2012 and 2013, respectively, and only one QTL was found in both two years, the phenotypic variation explained by this individual QTL was 13.5% and 17.2%, and the additive effects of this QTL contributed to the 9.9% and 14.3% decrease of disease index and therefore the disease resistance increased. The direction of the additive effects at five loci qFsr2a, qFsr8a, qFsr8b, qFsr11 and qFsr12 coincided with that predicted by phenotypes of the parents, and the IR28 alleles at these loci had positive effect against rice false smut while the negative effects were found in Daguandao alleles at qFsr2b and qFsr7. The qFsr11 should be useful in rice breeding for resistance to rice false smut in marker-assisted selection （MAS） program.展开更多
The pharmacokinetics of a sustained- release formulation and an enteric- coated tablet of diclofenac sodium were studied on 8 healthy male volunteers in an open,randomized crossover study.Drug level in serum was assay...The pharmacokinetics of a sustained- release formulation and an enteric- coated tablet of diclofenac sodium were studied on 8 healthy male volunteers in an open,randomized crossover study.Drug level in serum was assayed by HPLC method.The changes in serum concentration were conformed to a l-compartment open model.The t_1/2 (Ke)averaged 2.15±0.17 and ll.60 ± l.95 h,and the areas under the drug concentration curves were 5.87 ± 0.67 and 5.55 ± 0.57μgh/ml for enteric-coated and sustained-release tablet of diclofenac sodium,respectively. The mean relative bioavailability of sustained-release tablet was 0.95 to that of enteric-coated tablet.展开更多
Large-scale array aided beamforming improves the spectral efficiency(SE) as a benefit of high angular resolution.When dual-beam downlink beamforming is applied to the train moving towards cell edge,the inter-beam ambi...Large-scale array aided beamforming improves the spectral efficiency(SE) as a benefit of high angular resolution.When dual-beam downlink beamforming is applied to the train moving towards cell edge,the inter-beam ambiguity(IBA) increases as the directional difference between beams becomes smaller.An adaptive antenna activation based beamforming scheme was proposed to mitigate IBA.In the district near the base station(BS),all antenna elements(AEs) were activated to generate two beams.As the distance from the train to the BS increased,only the minimum number of AEs satisfying the resolution criterion would be activated.At the cell edge,one beam was switched off due to intolerable IBA.The proposed scheme can achieve SE gain to the non-adaptive scheme and show more robustness against the direction-of-arrival(DOA) estimation error.展开更多
The optical wireless communication (OWC) is afading channel because of the effect of atmosphericattenuation. We introduce a cumulant-based adaptive detection technique to providehigh performance for OWC. The received ...The optical wireless communication (OWC) is afading channel because of the effect of atmosphericattenuation. We introduce a cumulant-based adaptive detection technique to providehigh performance for OWC. The received signalof OWC over strong turbulence channels is assumedto be a mixture of K-distributed fading andGaussian distributed thermal noise. In order tomitigate the fading induced by turbulence, thedecision threshold-updating algorithm based onsecond and higher order cumulants is proposed,which is able to operate in an unknown turbulenceenvironment. The performance of the adaptiveprocessing scheme has been evaluated by meansof Monte Carlo simulations. It is shown that theproposed approach proves valuable for a limitednumber K of memory data.展开更多
The collective motion of rounded squares with different comer-roundness ζ is studied by molecular dynamlcs （MD） simulation in this work. Three types of translational collective motion pattern are observed, includin...The collective motion of rounded squares with different comer-roundness ζ is studied by molecular dynamlcs （MD） simulation in this work. Three types of translational collective motion pattern are observed, including＇, gliding, hopping and a mixture of gliding and hopping. Quantitatively, the dynamics of each observed ordered phase is characterized by both mean square displacement and van Hove functions for both translation and rotation. The effect of corner-roundness on the dynamics is further studied by comparing the dynamics of the rhombic crystal phases folmed by different comer-.rounded particles at a same surface fraction. The results show that as ζ increases from 0.286 to 0.667, the translational collective motion of particles changes from a gliding-dominant pattern to a hopping-dominant patte;n, whereas the rotational motion pattern is hopping-like and does not change in its type, but the rotational hopping becomes much more frequent as increases （i.e., as particles become more rounded）. A simple geometrical model is proposed to explain the trend of gliding motion observed in MD simulations.展开更多
This article establishes the precise asymptotics Eu^m(t, x)(t → ∞ or m → ∞) for the stochastic heat equation ?u/?t(t, x) =1/2?u(t, x) + u(t, x)(t, x)?W/?t(t, x) with the time-derivative Gaussian noise W?/?t(t, x) ...This article establishes the precise asymptotics Eu^m(t, x)(t → ∞ or m → ∞) for the stochastic heat equation ?u/?t(t, x) =1/2?u(t, x) + u(t, x)(t, x)?W/?t(t, x) with the time-derivative Gaussian noise W?/?t(t, x) that is fractional in time and homogeneous in space.展开更多
The amino acids are necessarily nutritious components, their diffusions in body fluid and blood that be- long to typical non-Newtonian fluid are of virtual importance to control the diffusive process and help clinical...The amino acids are necessarily nutritious components, their diffusions in body fluid and blood that be- long to typical non-Newtonian fluid are of virtual importance to control the diffusive process and help clinical treatment. In this article, a holographic interferometer has been adopted to measure the diffusivity of amino acids in non-Newtonian fluid with the use of real-time holographic interference technique. In order to prove the reliability of the experimental instrument, the diffusivities of sucrose aqueous solution at 298.15K were determined. The meas- ured result displays a satisfactory accuracy of the apparatus used. Furthermore, the diffusion coefficients of glynine, L-serine, L-threonine and L-valine in polyacrylamide (PAM) aqueous solution at 298.15K were measured, respec- tively. The experimental data were fitted by a newly proposed correlation equation based on Li’s predictive model. The calculating results by the present model are at considerably good agreement with experimental values, and the maximum average deviation is only 0.5%.展开更多
A class of latent ancestral graph for modelling the dependence structure of structural vector autoregressive （VAR） model affected by latent variables is proposed. The graphs are mixed graphs with possibly two kind o...A class of latent ancestral graph for modelling the dependence structure of structural vector autoregressive （VAR） model affected by latent variables is proposed. The graphs are mixed graphs with possibly two kind of edges, namely directed and bidirected edges. The vertex set denotes random variables at dif- ferent times. In Gaussian case, the latent ancestral graph leads to a simple parameterization model. A modified iterative conditional fitting algorithm is presented to obtain maximum likelihood esti- mation of the parameters. Furthermore, a log-likelihood criterion is used to select the most appropriate models. Simulations are performed using illustrative examples and results are provided to demonstrate the validity of the methods.展开更多
Background Rupture of descending thoracic aorta is a rare but lethal disease. Compared with open surgery,thoracic endovascular aortic repair(TEVAR)becomes a less invasive procedure in emergent management of patients w...Background Rupture of descending thoracic aorta is a rare but lethal disease. Compared with open surgery,thoracic endovascular aortic repair(TEVAR)becomes a less invasive procedure in emergent management of patients with feasible anatomy. Nevertheless,mortality remains high as well as morbidity despite successful operation. The purpose of this study was to compare TEVAR with conservative therapy on the 30-day mortality of patients with ruptured descending thoracic aorta. Methods Retrospective analysis of patients admitted to our hospital with descending thoracic aortic rupture was performed. Patients presented with rupture of descending thoracic aorta with feasible anatomy for TEVAR between Jan 2014 and June 2019 were included. Patients were divided into operative and conservative group depending on which therapy they received. Patients received TEVAR were defined as the operative group,while those received conservative therapy were defined as conservative treatment group. Results There were twenty-six patients in total,including fifteen aortic dissections,nine were thoracic aneurysms,and two were traumatic injuries. Theie mean age was 60±13 years with only two female. Seven patients(27%)presented with shock and twenty-two(85%)was accompanied with hemothorax on admission. Nineteen patients(73%)accepted emergent TEVAR with 100% primary technical success,and the other seven received conservative treatment. In operative group,infection(89%)and respiratory failure(63%)occurred after TEVAR. The in-hospital mortality for operative and conservative treatment group was 26% and 57% respectively(P=0.18). Operative group had lower 30-day mortality(26% vs. 86%,P=0.021). Conclusions TEVAR is associated with improved early outcome in patients with ruptured descending thoracic aorta.[S Chin J Cardiol 2019;20(3):140-145]展开更多
OBJECTIVE To investigate the neuroprotective effects and exact mechanisms of myrrh extract following cerebral ischemic stroke.METHODS Male rats were randomly divided into three groups:sham group,middle cerebral artery...OBJECTIVE To investigate the neuroprotective effects and exact mechanisms of myrrh extract following cerebral ischemic stroke.METHODS Male rats were randomly divided into three groups:sham group,middle cerebral artery occlusion(MCAO)group and myrrh group.Morphological changes were assessed after 7 d of myrrh treatment.Microarray analysis with circulating mRNA was performed to identify differential gene expression profile,gene ontology and pathway enrichment analyses were carried out to predict the gene function.Gene co-expression and pathway networks were constructed to identify the potential targets.The markers of oxidative stress,inflammatory reaction and ferroptosis in the cerebral cortex were detected by ELISA assays.The identified hub pathways and genes were validated by western blotting,immunofluorescence and immunohistochemistry analyses.Neurons were exposed to transient oxygen-glucose deprivation(OGD)to model ischemia-like conditions.siRNA-TXNIP were transfected in OGD-induced neurons to explore the mechanism.RESULTS Myrrh extract significantly alleviated neurological deficits,infarct volume and histo⁃pathological damage in MCAO rats.A total of 2200 differentially expressed genes were identified among the three groups.Oxidation-reduction process,inflammatory response,ferroptosis were enriched as the significant gene ontology items.NOD-like receptor signaling were identified as the hub pathway based on the pathway relation network.TXNIP and NLRP3 were screened as the potential targets by a time sequence profile analysis.The levels of IL-1β,IL-18,TNF-α,MDA and TFR in brain tissues were increased while the CAT,SOD,GSH-px and GPX4 levels were significantly decreased in MCAO group.As expected,myrrh extract greatly reversed these changes.The similarly results were also observed in OGD treated neuron cells.The elevated expressions of TXNIP and NLRP3 induced by OGD were success⁃fully inhibited by myrrh treatment.Knockdown of TXNIP significantly alleviated OGD-induced ROS accumulation and oxidative stress,but the antioxidative effect of myrrh was impaired when TXNIP was absent in neuron cells.In addition,knockdown of TXNIP significantly decreased the expression of NLRP3 and increased the expression of GPX4 in OGDinduced neuron cells.However,myrrh treatment scarcely changed the expressions of NLRP3 and these ferroptosis markers in siRNA-TXNIP pretreated cells,compared with the siRNA-TXNIP alone treatment group.Therefore,these data demonstrated that the neuroprotective effect of myrrh extract was dependent on TXNIP-NLRP3 axis.CONCLU⁃SION Thatmyrrh extract exerts neuroprotective property through alleviated ROS-mediated ferroptosis by regulating the TXNIP/NLRP3 axis in ischemic stroke.Myrrh extract could be considered as a promising candidate for the treatment of ischemic stroke.展开更多
OBJECTIVE To clarify the role of translocator protein 18 ku(TSPO)on cecum liga⁃tion and puncture(CLP)induced sepsis associat⁃ed encephalopathy(SAE)mice,which consis⁃tently demonstrated astrocyte activation and neu⁃roi...OBJECTIVE To clarify the role of translocator protein 18 ku(TSPO)on cecum liga⁃tion and puncture(CLP)induced sepsis associat⁃ed encephalopathy(SAE)mice,which consis⁃tently demonstrated astrocyte activation and neu⁃roinflammation.Background SAE,a brain dys⁃function,caused by systemic infection without clinical or laboratory evidence of direct infection.Most patients have symptoms such as long-term cognitive dysfunction.As the pathogenesis of SAE is very complex,neuroinflammation for SAE is one of the causes of the disease.TSPO as a marker of neuroinflammation that has the poten⁃tial to regulate neuroinflammation and SAE.METHODS The animal model of SAE was in⁃duced by CLP.TSPO ligands and TSPO knock⁃out mice were used for behavioral and molecular biology research.Survival rate of mice within 120 h on CLP mice was observed.The changes of cog⁃nitive function in mice were observed by Morris water maze and open field test.The changes of proinflammatory factors(IL-1β,TNF-α,IL-6)in hippocampus were observed by ELISA;Astro⁃cyte activation,marked by GFAP,in hippocam⁃pal was analyzed by tissue immunofluorescence and Western blotting.RESULTS Pretreatment with the TSPO ligands,XBD173 or PK11195,sig⁃nificantly improved the survival rate of CLP mice.The results of Morris water maze showed that TSPO ligands significantly increased the number of crossing the platform and the target quadrant time on CLP mice,suggesting that TSPO ligands may improve the learning and memory ability of CLP mice.Subsequent experiments revealed that TSPO ligands can reduce the inflammatory factors(IL-1β,TNF-α,IL-6)and astrocyte activa⁃tion in hippocampus of CLP mice.Similar results were also confirmed in TSPO knockout CLP mice,suggesting intervention of TSPO can reduce neuroinflammatory response and play a protec⁃tive role on SAE mice.CONCLUSION TSPO may play a critical role on SAE mice.Targeting TSPO by pharmacological means may improve the survival rate and cognitive function on CLP mice,which may through inhibiting astrocyte acti⁃vation and neuroinflammation in hippocampal.展开更多
Dust aerosol optical depth (AOD) and its ac-companying shortwave radiative forcing (RF) are usually simulated by numerical models.Here,by using 9 months of Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol...Dust aerosol optical depth (AOD) and its ac-companying shortwave radiative forcing (RF) are usually simulated by numerical models.Here,by using 9 months of Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol product data in combination with Clouds and the Earth's Radiant Energy System Single Scanner Footprint (CERES/SSF) data,dust AOD and its shortwave RF were estimated over the cloud-free north-west (NW) Pacific Ocean in the springs of 2004,2005,and 2006.The results showed that in this region,the mean dust AOD and its shortwave RF were 0.10 and 5.51 W m 2,respectively.In order to validate the dust AOD de-rived by MODIS,results from the Goddard Global Ozone Chemistry Aerosol Radiation and Transport (GOCART) model were also used here.The correlation coefficient between the monthly averaged dust AOD derived by MODIS measurements and the model simulation results was approximately 0.53.Since the estimates of the dust AOD and its shortwave RF obtained in this study are based mainly on satellite data,they offer a good reference for numerical models.展开更多
OBJECTIVE Nicotinamide phos⁃phoribosyltransferase(NAMPT)is the key en⁃zyme in the NAD(nicotinamide adenine dinucleo⁃tide)salvaging synthesis pathway.The level of NAMPT and NAD decreases during ageing,which causes neur...OBJECTIVE Nicotinamide phos⁃phoribosyltransferase(NAMPT)is the key en⁃zyme in the NAD(nicotinamide adenine dinucleo⁃tide)salvaging synthesis pathway.The level of NAMPT and NAD decreases during ageing,which causes neurodegenerative diseases.How⁃ever,the study of neuron-and region-specific ge⁃netic disturbance of NAMPT on cognition impair⁃ment is still lacking.This study was to explore the consequences and mechanisms of hippo⁃campus CA1 neuron-specific knockout of NAMPT on mouse cognitive functions.METH⁃ODS Floxed three-month old Nampt(Namptflox/flox)mice were used,and injected rAAV-hSyn-Cre-APRE-pA into the hippocampus CA1 region to specifically knockout the nampt gene.The learn⁃ing and memory of mice was determined at one-month after the intracerebral injection of AAV.We used immunofluorescence and trans⁃mission electron microscopy to detect neuronal injury.Western blotting and ELISA were used to measure the change of protein level and small molecule level.RESULTS One month after the knockout of nampt gene,the level of NAD signifi⁃cantly decreased in mouse hippocampus.The hippocampus dependent cognition of mice was also significantly decreased when compared to the wild type mice.However,the locomotor ac⁃tivity and anxiety behavior remained un⁃changed.Though there was no neuronal loss,and the neuronal cell bodies remained morpholog⁃ically intact.The level of Tau and MAP2 signifi⁃cantly decreased and degenerative change was found by using transmission electron micro⁃scope,which indicating the injury of both den⁃drites and axons.Meanwhile,the neuronal injury increased the neuroinflammation indicated by the activation of astrocyte and microglia.CON⁃CLUSION The decline of NAMPT and NAD causes neurodegeneration and cognition impair⁃ment of mice.展开更多
Insomnia is a prominent problem.The current mainstream therapy for insomnia is cognitive behavioral therapy.Traditional Chinese medicine has rich clinical experience in treating insomnia,but we have ignored the contri...Insomnia is a prominent problem.The current mainstream therapy for insomnia is cognitive behavioral therapy.Traditional Chinese medicine has rich clinical experience in treating insomnia,but we have ignored the contribution of traditional Chinese medicine to behavioral therapy in the past.Completed in the Qing Dynasty in China,Laolao Hengyan is a comprehensive book on the management of the elderly's self-health.The book describes many ways to promote sleep health.This book inherits the traditional Chinese medical treatment concept and reflects traditional Chinese culture.By comparing this book with cognitive behavioral therapy,we find that the Chinese Qing Dynasty literature has documented some cognitive and behavioral aspects of sleep that are consistent with modern medical concepts.Moreover,this method is superior to modern medicine in some aspects,so this is worthy of our in-depth study to complement and enrich modern medical theory.展开更多
Biodegradable metals hold promises for bone fracture repair.Their clinical translation requires pre-clinical evaluations including animal studies,which demonstrate the safety and performance of such materials prior to...Biodegradable metals hold promises for bone fracture repair.Their clinical translation requires pre-clinical evaluations including animal studies,which demonstrate the safety and performance of such materials prior to clinical trials.This evidence-based study investigates and analyzes the performance of bone fractures repair as well as degr adation properties of biodegradable metals in animal models.Data were carefully collected after identification of population,interventions,com-parisons,outcomes and study design,as well as inclusion criteria combining biodegradable metals and animal study.Twelve publications on pure Mg,Mg alloys and Zn alloys were finally included and reviewed after extraction from a collected database of 2122 publications.Compared to controls of traditional non-degradable metals or resorbable polymers,biodegradable metals showed mixed or contradictory outcomes of fracture repair and degradation in animal models.Although quantita-tive meta-analysis cannot be conducted because of the data heterogeneity,this systematic review revealed that the quality of evidence for biodegradable metals to repair bone fractures in animal models is'very low'.Recommendations to standardize the animal studies of biodegradable metals were proposed.Evidence based biomaterials research could help to both identify reliable scientific evidence and ensure future clinical translation of biodegradable metals for bone fracture repair.展开更多
Objective To evaluate the toxic response to intrahepatic arterial admin istration of radioactive phosphorus32 glass microspheres (32 P GMS) in domestic pigs Methods Through selective catheterization of hepatic artery...Objective To evaluate the toxic response to intrahepatic arterial admin istration of radioactive phosphorus32 glass microspheres (32 P GMS) in domestic pigs Methods Through selective catheterization of hepatic artery,32P GMS was infused to 5 healthy domestic pigs in a dosage equivalent to the thera peutic dose for human being, and31PGMS was infused to other 5 healthy domestic pigs Two pigs se rved as the whole course blank controls One pig from each group was surrendere d to euthanasia at week 1, 2, 4, 8 and 16, respectively, and liver biopsies were performed on the rest of pigs at the corresponding time points Liver tissues f r om different sites were taken for light and electron microscopy The ultrastruc t ural histopathological changes were evaluated semiquantitatively Results The accumulative amount of32PGMS in the target tissue attained more th an 90% of the total dose administrated Histologically, abnormal hepatocytes we re easily found at week 1 or 2 At week 4 they were less than at week 1 or 2, a n d endothelium of the sinuses were damaged prominently At week 8 they were scar cely seen, and liver tissue recovered gradually The histological features of l i ver tissue restored to normal at week 16 Semiquantitative analysis of ultrastr u ctural morphology in the experimental group showed no statistical difference ( P >050) between the nuclear abnormality (Nabn) and mitochrondri a l variability (Mvar) at week 1 or 2, but revealed prominent difference ( P <001, P <0001) as compared with those in other groups I n the experimental group the Nabn in tissues showed no significant differe nce ( P >020) between week 8 and week 16 Conclusion 32 PGMS internal irradiation at the dosag e equiva lent to human therapeutic dosage exerts reversible injury to domestic pig liver tissue, and it takes more than 8 weeks for the injured liver tissue to recover展开更多
THE oxidative dehydrogenation of propane （ODP） to propene is one of the potentially important catalytic processes for the effective utilization of light alkanes. The VMgO catalysts which have better catalytic perfor...THE oxidative dehydrogenation of propane （ODP） to propene is one of the potentially important catalytic processes for the effective utilization of light alkanes. The VMgO catalysts which have better catalytic performances for the reaction have aroused much interest and argument.Kung et al. proposed that the active phase was magnesium orthovanadate （Mg<sub>3</sub>V<sub>2</sub>O<sub>8</sub>）, but Volta et al. suggested that magnesium pyrovanadate （α-Mg<sub>2</sub>V<sub>2</sub>O<sub>7</sub>） was the active phase; in this phase, V<sup>4+</sup> ions which are associated to the formation of oxygen vacancies could stably exist, and Mg<sub>3</sub>V<sub>2</sub>O<sub>8</sub> is responsible for the total oxidation due to nonexistence of V<sup>4+</sup> ions.展开更多
基金Supported by the National Natural Science Foundation of China(31071397)the Agricultural Science and Technology Innovation Fund Project of Jiangsu Province(CX(15)1054)~~
文摘In order to identify the resistant gene of rice false smut in rice, a recombi- nant inbred line （RILs） population with 157 lines derived from an inter-subspecies cross of Daguandao/IR28 by the single seed descent method was used to detect quantitative trait loci （QTLs） conferring resistance to strain Pi-1 of rice false smut caused by Usti/aginoiclea virens （Cooke） Takahashi in 2012 and 2013. The disease rate indexes of the two parents and 157 RILs caused by the strain Pi-1 of rice false smut were scored and the QTLs for rice false smut resistance were detected accordingly by QTL Cartographer software. Seven QTLs controlling false smut re- sistance were detected on chromosomes 2, 7, 8, 11 and 12, respectively, with the phenotypic variance of 8.5%-17.2%. There were four QTLs detected in 2012 and 2013, respectively, and only one QTL was found in both two years, the phenotypic variation explained by this individual QTL was 13.5% and 17.2%, and the additive effects of this QTL contributed to the 9.9% and 14.3% decrease of disease index and therefore the disease resistance increased. The direction of the additive effects at five loci qFsr2a, qFsr8a, qFsr8b, qFsr11 and qFsr12 coincided with that predicted by phenotypes of the parents, and the IR28 alleles at these loci had positive effect against rice false smut while the negative effects were found in Daguandao alleles at qFsr2b and qFsr7. The qFsr11 should be useful in rice breeding for resistance to rice false smut in marker-assisted selection （MAS） program.
文摘The pharmacokinetics of a sustained- release formulation and an enteric- coated tablet of diclofenac sodium were studied on 8 healthy male volunteers in an open,randomized crossover study.Drug level in serum was assayed by HPLC method.The changes in serum concentration were conformed to a l-compartment open model.The t_1/2 (Ke)averaged 2.15±0.17 and ll.60 ± l.95 h,and the areas under the drug concentration curves were 5.87 ± 0.67 and 5.55 ± 0.57μgh/ml for enteric-coated and sustained-release tablet of diclofenac sodium,respectively. The mean relative bioavailability of sustained-release tablet was 0.95 to that of enteric-coated tablet.
基金supported partially by the 973 Program under the Grant 2012CB316100
文摘Large-scale array aided beamforming improves the spectral efficiency(SE) as a benefit of high angular resolution.When dual-beam downlink beamforming is applied to the train moving towards cell edge,the inter-beam ambiguity(IBA) increases as the directional difference between beams becomes smaller.An adaptive antenna activation based beamforming scheme was proposed to mitigate IBA.In the district near the base station(BS),all antenna elements(AEs) were activated to generate two beams.As the distance from the train to the BS increased,only the minimum number of AEs satisfying the resolution criterion would be activated.At the cell edge,one beam was switched off due to intolerable IBA.The proposed scheme can achieve SE gain to the non-adaptive scheme and show more robustness against the direction-of-arrival(DOA) estimation error.
文摘The optical wireless communication (OWC) is afading channel because of the effect of atmosphericattenuation. We introduce a cumulant-based adaptive detection technique to providehigh performance for OWC. The received signalof OWC over strong turbulence channels is assumedto be a mixture of K-distributed fading andGaussian distributed thermal noise. In order tomitigate the fading induced by turbulence, thedecision threshold-updating algorithm based onsecond and higher order cumulants is proposed,which is able to operate in an unknown turbulenceenvironment. The performance of the adaptiveprocessing scheme has been evaluated by meansof Monte Carlo simulations. It is shown that theproposed approach proves valuable for a limitednumber K of memory data.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.21573159 and 21621004)
文摘The collective motion of rounded squares with different comer-roundness ζ is studied by molecular dynamlcs （MD） simulation in this work. Three types of translational collective motion pattern are observed, including＇, gliding, hopping and a mixture of gliding and hopping. Quantitatively, the dynamics of each observed ordered phase is characterized by both mean square displacement and van Hove functions for both translation and rotation. The effect of corner-roundness on the dynamics is further studied by comparing the dynamics of the rhombic crystal phases folmed by different comer-.rounded particles at a same surface fraction. The results show that as ζ increases from 0.286 to 0.667, the translational collective motion of particles changes from a gliding-dominant pattern to a hopping-dominant patte;n, whereas the rotational motion pattern is hopping-like and does not change in its type, but the rotational hopping becomes much more frequent as increases （i.e., as particles become more rounded）. A simple geometrical model is proposed to explain the trend of gliding motion observed in MD simulations.
基金Research partially supported by the “1000 Talents Plan” from Jilin University,Jilin Province and Chinese Governmentby the Simons Foundation(244767)
文摘This article establishes the precise asymptotics Eu^m(t, x)(t → ∞ or m → ∞) for the stochastic heat equation ?u/?t(t, x) =1/2?u(t, x) + u(t, x)(t, x)?W/?t(t, x) with the time-derivative Gaussian noise W?/?t(t, x) that is fractional in time and homogeneous in space.
基金Supported by the National Natural Science Foundation of China (No.20476073).
文摘The amino acids are necessarily nutritious components, their diffusions in body fluid and blood that be- long to typical non-Newtonian fluid are of virtual importance to control the diffusive process and help clinical treatment. In this article, a holographic interferometer has been adopted to measure the diffusivity of amino acids in non-Newtonian fluid with the use of real-time holographic interference technique. In order to prove the reliability of the experimental instrument, the diffusivities of sucrose aqueous solution at 298.15K were determined. The meas- ured result displays a satisfactory accuracy of the apparatus used. Furthermore, the diffusion coefficients of glynine, L-serine, L-threonine and L-valine in polyacrylamide (PAM) aqueous solution at 298.15K were measured, respec- tively. The experimental data were fitted by a newly proposed correlation equation based on Li’s predictive model. The calculating results by the present model are at considerably good agreement with experimental values, and the maximum average deviation is only 0.5%.
基金supported in part by the National Natural Science Foundation of China(60375003)the Aeronautics and Astronautics Basal Science Foundation of China(03I53059)
文摘A class of latent ancestral graph for modelling the dependence structure of structural vector autoregressive （VAR） model affected by latent variables is proposed. The graphs are mixed graphs with possibly two kind of edges, namely directed and bidirected edges. The vertex set denotes random variables at dif- ferent times. In Gaussian case, the latent ancestral graph leads to a simple parameterization model. A modified iterative conditional fitting algorithm is presented to obtain maximum likelihood esti- mation of the parameters. Furthermore, a log-likelihood criterion is used to select the most appropriate models. Simulations are performed using illustrative examples and results are provided to demonstrate the validity of the methods.
基金supported by the National Natural Science Fund(No.81602848)
文摘Background Rupture of descending thoracic aorta is a rare but lethal disease. Compared with open surgery,thoracic endovascular aortic repair(TEVAR)becomes a less invasive procedure in emergent management of patients with feasible anatomy. Nevertheless,mortality remains high as well as morbidity despite successful operation. The purpose of this study was to compare TEVAR with conservative therapy on the 30-day mortality of patients with ruptured descending thoracic aorta. Methods Retrospective analysis of patients admitted to our hospital with descending thoracic aortic rupture was performed. Patients presented with rupture of descending thoracic aorta with feasible anatomy for TEVAR between Jan 2014 and June 2019 were included. Patients were divided into operative and conservative group depending on which therapy they received. Patients received TEVAR were defined as the operative group,while those received conservative therapy were defined as conservative treatment group. Results There were twenty-six patients in total,including fifteen aortic dissections,nine were thoracic aneurysms,and two were traumatic injuries. Theie mean age was 60±13 years with only two female. Seven patients(27%)presented with shock and twenty-two(85%)was accompanied with hemothorax on admission. Nineteen patients(73%)accepted emergent TEVAR with 100% primary technical success,and the other seven received conservative treatment. In operative group,infection(89%)and respiratory failure(63%)occurred after TEVAR. The in-hospital mortality for operative and conservative treatment group was 26% and 57% respectively(P=0.18). Operative group had lower 30-day mortality(26% vs. 86%,P=0.021). Conclusions TEVAR is associated with improved early outcome in patients with ruptured descending thoracic aorta.[S Chin J Cardiol 2019;20(3):140-145]
基金National Natural Science Foundation of China(8167363181603385)+2 种基金China Postdoctoral Science Foundation(2018M643843)Natural Science Foundation of Shaanxi Province(2017JM8056)Key Research and Development Foundation of Shaanxi province(2018SF-241)
文摘OBJECTIVE To investigate the neuroprotective effects and exact mechanisms of myrrh extract following cerebral ischemic stroke.METHODS Male rats were randomly divided into three groups:sham group,middle cerebral artery occlusion(MCAO)group and myrrh group.Morphological changes were assessed after 7 d of myrrh treatment.Microarray analysis with circulating mRNA was performed to identify differential gene expression profile,gene ontology and pathway enrichment analyses were carried out to predict the gene function.Gene co-expression and pathway networks were constructed to identify the potential targets.The markers of oxidative stress,inflammatory reaction and ferroptosis in the cerebral cortex were detected by ELISA assays.The identified hub pathways and genes were validated by western blotting,immunofluorescence and immunohistochemistry analyses.Neurons were exposed to transient oxygen-glucose deprivation(OGD)to model ischemia-like conditions.siRNA-TXNIP were transfected in OGD-induced neurons to explore the mechanism.RESULTS Myrrh extract significantly alleviated neurological deficits,infarct volume and histo⁃pathological damage in MCAO rats.A total of 2200 differentially expressed genes were identified among the three groups.Oxidation-reduction process,inflammatory response,ferroptosis were enriched as the significant gene ontology items.NOD-like receptor signaling were identified as the hub pathway based on the pathway relation network.TXNIP and NLRP3 were screened as the potential targets by a time sequence profile analysis.The levels of IL-1β,IL-18,TNF-α,MDA and TFR in brain tissues were increased while the CAT,SOD,GSH-px and GPX4 levels were significantly decreased in MCAO group.As expected,myrrh extract greatly reversed these changes.The similarly results were also observed in OGD treated neuron cells.The elevated expressions of TXNIP and NLRP3 induced by OGD were success⁃fully inhibited by myrrh treatment.Knockdown of TXNIP significantly alleviated OGD-induced ROS accumulation and oxidative stress,but the antioxidative effect of myrrh was impaired when TXNIP was absent in neuron cells.In addition,knockdown of TXNIP significantly decreased the expression of NLRP3 and increased the expression of GPX4 in OGDinduced neuron cells.However,myrrh treatment scarcely changed the expressions of NLRP3 and these ferroptosis markers in siRNA-TXNIP pretreated cells,compared with the siRNA-TXNIP alone treatment group.Therefore,these data demonstrated that the neuroprotective effect of myrrh extract was dependent on TXNIP-NLRP3 axis.CONCLU⁃SION Thatmyrrh extract exerts neuroprotective property through alleviated ROS-mediated ferroptosis by regulating the TXNIP/NLRP3 axis in ischemic stroke.Myrrh extract could be considered as a promising candidate for the treatment of ischemic stroke.
基金Joint Funds for the Innovation of Science and Technology of Fujian Province(2019Y9009)and Natural Science Foundation of Fujian Province(2020J01618)。
文摘OBJECTIVE To clarify the role of translocator protein 18 ku(TSPO)on cecum liga⁃tion and puncture(CLP)induced sepsis associat⁃ed encephalopathy(SAE)mice,which consis⁃tently demonstrated astrocyte activation and neu⁃roinflammation.Background SAE,a brain dys⁃function,caused by systemic infection without clinical or laboratory evidence of direct infection.Most patients have symptoms such as long-term cognitive dysfunction.As the pathogenesis of SAE is very complex,neuroinflammation for SAE is one of the causes of the disease.TSPO as a marker of neuroinflammation that has the poten⁃tial to regulate neuroinflammation and SAE.METHODS The animal model of SAE was in⁃duced by CLP.TSPO ligands and TSPO knock⁃out mice were used for behavioral and molecular biology research.Survival rate of mice within 120 h on CLP mice was observed.The changes of cog⁃nitive function in mice were observed by Morris water maze and open field test.The changes of proinflammatory factors(IL-1β,TNF-α,IL-6)in hippocampus were observed by ELISA;Astro⁃cyte activation,marked by GFAP,in hippocam⁃pal was analyzed by tissue immunofluorescence and Western blotting.RESULTS Pretreatment with the TSPO ligands,XBD173 or PK11195,sig⁃nificantly improved the survival rate of CLP mice.The results of Morris water maze showed that TSPO ligands significantly increased the number of crossing the platform and the target quadrant time on CLP mice,suggesting that TSPO ligands may improve the learning and memory ability of CLP mice.Subsequent experiments revealed that TSPO ligands can reduce the inflammatory factors(IL-1β,TNF-α,IL-6)and astrocyte activa⁃tion in hippocampus of CLP mice.Similar results were also confirmed in TSPO knockout CLP mice,suggesting intervention of TSPO can reduce neuroinflammatory response and play a protec⁃tive role on SAE mice.CONCLUSION TSPO may play a critical role on SAE mice.Targeting TSPO by pharmacological means may improve the survival rate and cognitive function on CLP mice,which may through inhibiting astrocyte acti⁃vation and neuroinflammation in hippocampal.
基金supported by the National Basic Research Program of China (Grant No.2006CB403705)Key Projects in the National Science & Technology Pillar Program in the Eleventh Five-year Plan Period (Grant No.2008BAC40B01 and 2007BAC03A01)LASG Free Exploration Fund
文摘Dust aerosol optical depth (AOD) and its ac-companying shortwave radiative forcing (RF) are usually simulated by numerical models.Here,by using 9 months of Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol product data in combination with Clouds and the Earth's Radiant Energy System Single Scanner Footprint (CERES/SSF) data,dust AOD and its shortwave RF were estimated over the cloud-free north-west (NW) Pacific Ocean in the springs of 2004,2005,and 2006.The results showed that in this region,the mean dust AOD and its shortwave RF were 0.10 and 5.51 W m 2,respectively.In order to validate the dust AOD de-rived by MODIS,results from the Goddard Global Ozone Chemistry Aerosol Radiation and Transport (GOCART) model were also used here.The correlation coefficient between the monthly averaged dust AOD derived by MODIS measurements and the model simulation results was approximately 0.53.Since the estimates of the dust AOD and its shortwave RF obtained in this study are based mainly on satellite data,they offer a good reference for numerical models.
文摘OBJECTIVE Nicotinamide phos⁃phoribosyltransferase(NAMPT)is the key en⁃zyme in the NAD(nicotinamide adenine dinucleo⁃tide)salvaging synthesis pathway.The level of NAMPT and NAD decreases during ageing,which causes neurodegenerative diseases.How⁃ever,the study of neuron-and region-specific ge⁃netic disturbance of NAMPT on cognition impair⁃ment is still lacking.This study was to explore the consequences and mechanisms of hippo⁃campus CA1 neuron-specific knockout of NAMPT on mouse cognitive functions.METH⁃ODS Floxed three-month old Nampt(Namptflox/flox)mice were used,and injected rAAV-hSyn-Cre-APRE-pA into the hippocampus CA1 region to specifically knockout the nampt gene.The learn⁃ing and memory of mice was determined at one-month after the intracerebral injection of AAV.We used immunofluorescence and trans⁃mission electron microscopy to detect neuronal injury.Western blotting and ELISA were used to measure the change of protein level and small molecule level.RESULTS One month after the knockout of nampt gene,the level of NAD signifi⁃cantly decreased in mouse hippocampus.The hippocampus dependent cognition of mice was also significantly decreased when compared to the wild type mice.However,the locomotor ac⁃tivity and anxiety behavior remained un⁃changed.Though there was no neuronal loss,and the neuronal cell bodies remained morpholog⁃ically intact.The level of Tau and MAP2 signifi⁃cantly decreased and degenerative change was found by using transmission electron micro⁃scope,which indicating the injury of both den⁃drites and axons.Meanwhile,the neuronal injury increased the neuroinflammation indicated by the activation of astrocyte and microglia.CON⁃CLUSION The decline of NAMPT and NAD causes neurodegeneration and cognition impair⁃ment of mice.
文摘Insomnia is a prominent problem.The current mainstream therapy for insomnia is cognitive behavioral therapy.Traditional Chinese medicine has rich clinical experience in treating insomnia,but we have ignored the contribution of traditional Chinese medicine to behavioral therapy in the past.Completed in the Qing Dynasty in China,Laolao Hengyan is a comprehensive book on the management of the elderly's self-health.The book describes many ways to promote sleep health.This book inherits the traditional Chinese medical treatment concept and reflects traditional Chinese culture.By comparing this book with cognitive behavioral therapy,we find that the Chinese Qing Dynasty literature has documented some cognitive and behavioral aspects of sleep that are consistent with modern medical concepts.Moreover,this method is superior to modern medicine in some aspects,so this is worthy of our in-depth study to complement and enrich modern medical theory.
基金We acknowledge the financial support from the National Natural Science Foundation of China(81873184).
文摘Biodegradable metals hold promises for bone fracture repair.Their clinical translation requires pre-clinical evaluations including animal studies,which demonstrate the safety and performance of such materials prior to clinical trials.This evidence-based study investigates and analyzes the performance of bone fractures repair as well as degr adation properties of biodegradable metals in animal models.Data were carefully collected after identification of population,interventions,com-parisons,outcomes and study design,as well as inclusion criteria combining biodegradable metals and animal study.Twelve publications on pure Mg,Mg alloys and Zn alloys were finally included and reviewed after extraction from a collected database of 2122 publications.Compared to controls of traditional non-degradable metals or resorbable polymers,biodegradable metals showed mixed or contradictory outcomes of fracture repair and degradation in animal models.Although quantita-tive meta-analysis cannot be conducted because of the data heterogeneity,this systematic review revealed that the quality of evidence for biodegradable metals to repair bone fractures in animal models is'very low'.Recommendations to standardize the animal studies of biodegradable metals were proposed.Evidence based biomaterials research could help to both identify reliable scientific evidence and ensure future clinical translation of biodegradable metals for bone fracture repair.
文摘Objective To evaluate the toxic response to intrahepatic arterial admin istration of radioactive phosphorus32 glass microspheres (32 P GMS) in domestic pigs Methods Through selective catheterization of hepatic artery,32P GMS was infused to 5 healthy domestic pigs in a dosage equivalent to the thera peutic dose for human being, and31PGMS was infused to other 5 healthy domestic pigs Two pigs se rved as the whole course blank controls One pig from each group was surrendere d to euthanasia at week 1, 2, 4, 8 and 16, respectively, and liver biopsies were performed on the rest of pigs at the corresponding time points Liver tissues f r om different sites were taken for light and electron microscopy The ultrastruc t ural histopathological changes were evaluated semiquantitatively Results The accumulative amount of32PGMS in the target tissue attained more th an 90% of the total dose administrated Histologically, abnormal hepatocytes we re easily found at week 1 or 2 At week 4 they were less than at week 1 or 2, a n d endothelium of the sinuses were damaged prominently At week 8 they were scar cely seen, and liver tissue recovered gradually The histological features of l i ver tissue restored to normal at week 16 Semiquantitative analysis of ultrastr u ctural morphology in the experimental group showed no statistical difference ( P >050) between the nuclear abnormality (Nabn) and mitochrondri a l variability (Mvar) at week 1 or 2, but revealed prominent difference ( P <001, P <0001) as compared with those in other groups I n the experimental group the Nabn in tissues showed no significant differe nce ( P >020) between week 8 and week 16 Conclusion 32 PGMS internal irradiation at the dosag e equiva lent to human therapeutic dosage exerts reversible injury to domestic pig liver tissue, and it takes more than 8 weeks for the injured liver tissue to recover
文摘THE oxidative dehydrogenation of propane （ODP） to propene is one of the potentially important catalytic processes for the effective utilization of light alkanes. The VMgO catalysts which have better catalytic performances for the reaction have aroused much interest and argument.Kung et al. proposed that the active phase was magnesium orthovanadate （Mg<sub>3</sub>V<sub>2</sub>O<sub>8</sub>）, but Volta et al. suggested that magnesium pyrovanadate （α-Mg<sub>2</sub>V<sub>2</sub>O<sub>7</sub>） was the active phase; in this phase, V<sup>4+</sup> ions which are associated to the formation of oxygen vacancies could stably exist, and Mg<sub>3</sub>V<sub>2</sub>O<sub>8</sub> is responsible for the total oxidation due to nonexistence of V<sup>4+</sup> ions.
