Central nervous system injuries have a high rate of resulting in disability and mortality;however,at present,effective treatments are lacking.Programmed cell death,which is a genetically determined fo rm of active and...Central nervous system injuries have a high rate of resulting in disability and mortality;however,at present,effective treatments are lacking.Programmed cell death,which is a genetically determined fo rm of active and ordered cell death with many types,has recently attra cted increasing attention due to its functions in determining the fate of cell survival.A growing number of studies have suggested that programmed cell death is involved in central nervous system injuries and plays an important role in the progression of brain damage.In this review,we provide an ove rview of the role of programmed cell death in central nervous system injuries,including the pathways involved in mitophagy,pyroptosis,ferroptosis,and necroptosis,and the underlying mechanisms by which mitophagy regulates pyroptosis,ferroptosis,and necro ptosis.We also discuss the new direction of therapeutic strategies to rgeting mitophagy for the treatment of central nervous system injuries,with the aim to determine the connection between programmed cell death and central nervous system injuries and to identify new therapies to modulate programmed cell death following central nervous system injury.In conclusion,based on these properties and effects,interventions targeting programmed cell death could be developed as potential therapeutic agents for central nervous system injury patients.展开更多
Hydrogen holds the advantages of high energy density,great natural abundance and zero emission,making it suitable for large scale and long term energy storage,while its safe and efficient storage is still challenging....Hydrogen holds the advantages of high energy density,great natural abundance and zero emission,making it suitable for large scale and long term energy storage,while its safe and efficient storage is still challenging.Among various solid state hydrogen storage materials,MgH_(2) is promising for industrial applications due to its high gravimetric and volumetric hydrogen densities and the abundance of Mg on earth.However,the practical application of MgH_(2) has been limited by its stable thermodynamics and slow hydrogen desorption kinetics.Nanocatalysis is considered as a promising approach for improving the hydrogen storage performance of MgH_(2) and bringing it closer to the requirements of commercial applications.It is worth mentioning that the recently emerging two-dimensional material,MXene,has showcased exceptional catalytic abilities in modifying the hydrogen storage properties of MgH_(2).Besides,MXene possesses a high surface area,excellent chemical/physical stability,and negatively charged terminating groups,making it an ideal support for the"nanoconfinement"of MgH_(2) or highly active catalysts.Herein,we endeavor to provide a comprehensive overview of recent investigations on MXene-based catalysts and MXene supports for improving the hydrogen sorption properties of Mg/MgH_(2).The mechanisms of hydrogen sorption involved in Mg-MXene based composites are highlighted with special emphases on thermodynamics,kinetics,and catalytic behaviors.The aim of this work is to provide a comprehensive and objective review of researches on the development of high-performance catalysts/supports to improve hydrogen storage performances of Mg/MgH_(2) and to identify the opportunities and challenges for future applications.展开更多
As one of the Analysis Centers(AC)of the International GNSS Service(IGS),Wuhan University(WHU)has been contributing to the IGS by providing ultra-rapid as well as rapid orbit and clock solutions for the established GP...As one of the Analysis Centers(AC)of the International GNSS Service(IGS),Wuhan University(WHU)has been contributing to the IGS by providing ultra-rapid as well as rapid orbit and clock solutions for the established GPS and GLONASS since 2012.In the same year,the IGS initiated the Multi-GNSS Experiment(MGEX)to support the analysis of the emerging GNSS systems and prepare the IGS for Multi-GNSS,which includes GPS,GLONASS,the European Galileo system,the Chinese Beidou Navigation Satellite System(BDS),the Japanese Quasi-Zenith Satellite System(QZSS)and the Indian Regional Navigation Satellite System(IRNSS/NaVIC).The major products,i.e.,orbits,Earth Orientation Parameters(EOPs),satellite clock as well as attitude have also been provided by WHU since 2012.More recently,WHU has engaged the third reprocessing of IGS for generating the highly accurate station coordinates as inputs for establishment of the International Terrestrial Reference Frame(ITRF)2020 during 2019—2020.This article presents the recent major advancements of the IGS AC at Wuhan University,including precise products,real-time products,bias products,antenna phase center calibration,and the non-linear motion modeling for GNSS Reference Stations.展开更多
Objective: To develop a kind self active resistance movement training equipment for cervical spine, so as to restore the dynamic balance of the front and back muscle strength of the cervical spine in order to correct ...Objective: To develop a kind self active resistance movement training equipment for cervical spine, so as to restore the dynamic balance of the front and back muscle strength of the cervical spine in order to correct the abnormal physiological radian of the cervical spine, thereby relieving the clinical symptoms. Methods: The air spring with adjustable strength was used to provide the power of resistance active movement, and the neurological training cervical audio-visual synthesis training software was used to automatically guide patients to perform resistance active movement training of the cervical spine. Thirty two patients with cervical spondylosis were enrolled for treatment, and SPSS26 was used to statistically analyze the VAS, Lovett muscle strength, head and neck range of motion and C2-3 vertebral body curvature before and after the treatment. Result: There were significant differences in posterior cervical muscle strength (Lovett), dizziness, shoulder and neck pain (VAS) and C2-3 vertebral curvature before and after training in 32 patients (p˂0.001). Conclusion: The application of neurological training cervical vertebra self rehabilitation training instrument can effectively relieve clinical symptoms, restore head and neck range of motion, improve nape muscle strength, restore the dynamic balance of front and rear cervical muscle strength, and also can correct the abnormal physiological radian of the cervical vertebra.展开更多
The growing trend of network virtualization results in a widespread adoption of virtual switches in virtualized environments. However, virtual switching is confronted with great performance challenges regarding packet...The growing trend of network virtualization results in a widespread adoption of virtual switches in virtualized environments. However, virtual switching is confronted with great performance challenges regarding packet classification especially in Open Flow-based software defined networks. This paper first takes an insight into packet classification in virtual Open Flow switching, and points out that its performance bottleneck is dominated by flow table traversals of multiple failed mask probing for each arrived packet. Then we are motivated to propose an efficient packet classification algorithm based on counting bloom filters. In particular, counting bloom filters are applied to predict the failures of flow table lookups with great possibilities, and bypass flow table traversals for failed mask probing. Finally, our proposed packet classification algorithm is evaluated with real network traffic traces by experiments. The experimental results indicate that our proposed algorithm outperforms the classical one in Open v Switch in terms of average search length, and contributes to promote virtual Open Flow switching performance.展开更多
Purpose： In this paper, we combined the method of co-word analysis and alluvial diagram to detect hot topics and illustrate their dynamics. Design/methodology/approach： Articles in the field of scientometrics were c...Purpose： In this paper, we combined the method of co-word analysis and alluvial diagram to detect hot topics and illustrate their dynamics. Design/methodology/approach： Articles in the field of scientometrics were chosen as research cases in this study. A time-sliced co-word network was generated and then clustered. Afterwards, we generated an alluvial diagram to show dynamic changes of hot topics, including their merges and splits over time. Findings： After analyzing the dynamic changes in the field of scientometrics from 2011 to 2015, we found that two clusters being merged did not mean that the old topics had disappeared and a totally new one had emerged. The topics were possibly still active the following year, but the newer topics had drawn more attention. The changes of hot topics reflected the shift in researchers＇ interests. subdivided and re-merged. For example, several topics as research progressed. Research topics in scientometrics were constantly a cluster involving ＂industry＂ was divided into Research limitations： When examining longer time periods, we encounter the problem of dealing with bigger data sets. Analyzing data year by year would be tedious, but if we combine, e.g. two years into one time slice, important details would be missed. Practical implications： This method can be applied to any research field to illustrate the dynamics of hot topics. It can indicate the promising directions for researchers and provide guidance to decision makers. Originality/value： The use of alluvial diagrams is a distinctive and meaningful approach to detecting hot topics and especially to illustrating their dynamics.展开更多
Purpose： Research fronts build on recent work, but using times cited as a traditional indicator to detect research fronts will inevitably result in a certain time lag. This study attempts to explore the effects of us...Purpose： Research fronts build on recent work, but using times cited as a traditional indicator to detect research fronts will inevitably result in a certain time lag. This study attempts to explore the effects of usage count as a new indicator to detect research fronts in shortening the time lag of classic indicators in research fronts detection. Design/methodology/approach： An exploratory study was conducted where the new indicator ＂usage count＂ was compared to the traditional citation count, ＂times cited,＂ in detecting research fronts of the regenerative medicine domain. An initial topic search of the term ＂regenerative medicine＂ returned 10,553 records published between 2000 and 2015 in the Web of Science （WoS）. We first ranked these records with usage count and times cited, respectively, and selected the top 2,000 records for each. We then performed a co-citation analysis in order to obtain the citing papers of the co-citation clusters as the research fronts. Finally, we compared the average publication year of the citing papers as well as the mean cited year of the co-citation clusters. Findings： The citing articles detected by usage count tend to be published more recently compared with times cited within the same research front. Moreover, research fronts detected by usage count tend to be within the last two years, which presents a higher immediacy and real-time feature compared to times cited. There is approximately a three-year time span among the mean cited years （known as ＂intellectual base＂） of all clusters generated by usage count and this figure is about four years in the network of times cited. In comparison to times cited, usage count is a dynamic and instant indicator. Research limitations： We are trying to find the cutting-edge research fronts, but those generated based on co-citations may refer to the hot research fronts. The usage count of older highly cited papers was not taken into consideration, because the usage count indicator released by WoS only reflects usage logs after February 2013. Practical implications： The article provides a new perspective on using usage count as a new indicator to detect research fronts.Originality/value： Usage count can greatly shorten the time lag in research fronts detection, which would be a promising complementary indicator in detection of the latest research fronts.展开更多
With the number of connected devices increasing rapidly,the access latency issue increases drastically in the edge cloud environment.Massive low time-constrained and data-intensive mobile applications require efficien...With the number of connected devices increasing rapidly,the access latency issue increases drastically in the edge cloud environment.Massive low time-constrained and data-intensive mobile applications require efficient replication strategies to decrease retrieval time.However,the determination of replicas is not reasonable in many previous works,which incurs high response delay.To this end,a correlation-aware replica prefetching(CRP)strategy based on the file correlation principle is proposed,which can prefetch the files with high access probability.The key is to determine and obtain the implicit high-value files effectively,which has a significant impact on the performance of CRP.To achieve the goal of accelerating the acquisition of implicit highvalue files,an access rule management method based on consistent hashing is proposed,and then the storage and query mechanisms for access rules based on adjacency list storage structure are further presented.The theoretical analysis and simulation results corroborate that CRP shortens average response time over 4.8%,improves average hit ratio over 4.2%,reduces transmitting data amount over 8.3%,and maintains replication frequency at a reasonable level when compared to other schemes.展开更多
Data-intensive computing is expected to be the next-generation IT computing paradigm. Data-intensive workflows in clouds are becoming more and more popular. How to schedule data-intensive workflow efficiently has beco...Data-intensive computing is expected to be the next-generation IT computing paradigm. Data-intensive workflows in clouds are becoming more and more popular. How to schedule data-intensive workflow efficiently has become the key issue. In this paper, first, we build a directed hypergraph model for data-intensive workflow, since Hypergraphs can more accurately model communication volume and better represent asymmetric problems, and the cut metric of hypergraphs is well suited for minimizing the total volume of communication.Second, we propose a concept data supportive ability to help the presentation of data-intensive workflow application and provide the merge operation details considering the data supportive ability. Third, we present an optimized hypergraph multi-level partitioning algorithm. Finally we bring a data reduced scheduling policy HEFT-P for data-intensive workflow. Through simulation,we compare HEFT-P with three typical workflow scheduling policies.The results indicate that HEFT-P could obtain reduced data scheduling and reduce the makespan of executing data-intensive展开更多
The number of Internet Web services has become increasingly large recently.Cloud services consumers face a critical challenge in selecting services from abundant candidates.Due to the uncertainty of Web service QoS an...The number of Internet Web services has become increasingly large recently.Cloud services consumers face a critical challenge in selecting services from abundant candidates.Due to the uncertainty of Web service QoS and the diversity of user characteristics,this paper proposes a Web service recommendation method based on cloud model and user personality(WSRCP),which employs cloud model similarity method to analyze the similarity of QoS feedback data among different users,to identify the user with high similarity to the potential user.Based on the QoS data of the users’feedback,Finally,user characteristic attribute Web service recommendation is implemented by personalized collaborative filtering algorithm.The experimental results on the WS-Dream dataset show that our approach not only solves the drawbacks of the sparse user service,but also improves the recommend accuracy.展开更多
Achieving dual regulation of the kinetics and thermodynamics of MgH_(2) is essential for the practical applications.In this study,a novel nanocomposite(In@Ti-MX)architected from single-/few-layered Ti_(3)C_(2) MXenes ...Achieving dual regulation of the kinetics and thermodynamics of MgH_(2) is essential for the practical applications.In this study,a novel nanocomposite(In@Ti-MX)architected from single-/few-layered Ti_(3)C_(2) MXenes and ultradispersed indium nanoparticles was prepared by a bottom-up self-assembly strategy and introduced into MgH_(2) to solve the above-mentioned problems.The MgH_(2)+In@Ti-MX composites demonstrate excellent hydrogen storage performance:The resultant In@Ti-MX demonstrated a positive effect on the hydrogen storage performance of MgH_(2)/Mg:the dehydrogenated rate of MgH_(2)+15 wt%In@Ti-MX reached the maximum at 330°C,which was 47°C lower than that of commercial MgH_(2);The hydrogenation enthalpy of the dehydrided MgH_(2)+15 wt%In@Ti-MX and MgH_(2)+25 wt%In@Ti-MX were determined to be−66.2±1.1 and−61.7±1.4 kJ·mol^(−1) H_(2).In situ high-energy synchrotron x-ray diffraction technique together with other microstructure analyses revealed that synergistic effects from Ti_(3)C_(2) MXenes and In nanoparticles(NPs)contributed to the improved kinetics and thermodynamics of MgH_(2)(Mg):Ti/TiH_(2) derived from Ti_(3)C_(2) MXenes accelerated the dissociation and recombination of hydrogen molecule/atoms,while In NPs reduced the thermodynamic stability of MgH_(2) by forming the Mg-In solution.Such a strategy of using dual-active hybrid structures to modify MgH_(2)/Mg provides a new insight for tuning both the hydrogen storage kinetics and thermodynamics of Mg-based hydrides.展开更多
Primary biliary cholangitis(PBC)is an autoimmune liver disease characterized by the destruction of intrahepatic small bile ducts and progressive cholestasis,eventually leading to liver cirrhosis and hepatic failure wi...Primary biliary cholangitis(PBC)is an autoimmune liver disease characterized by the destruction of intrahepatic small bile ducts and progressive cholestasis,eventually leading to liver cirrhosis and hepatic failure without appropriate treatment(Terziroli Beretta-Piccoli et al.,2019).展开更多
The Asteraceae (Compositae),a large plant family of approximately 24 000-35 000 species,accounts for^10% of all angiosperm species and contributes a lot to plant diversity.The most representative members of the Astera...The Asteraceae (Compositae),a large plant family of approximately 24 000-35 000 species,accounts for^10% of all angiosperm species and contributes a lot to plant diversity.The most representative members of the Asteraceae are the economically important chrysanthemums (Chrysanthemum L.)that diversified through reticulate evolution.Biodiversity is typically created by multiple evolutionary mechanisms such as wholegenome duplication 0NGD)or polyploidization and locally repetitive genome expansion.However,the lack of genomic data from chrysanthemum species has prevented an in-depth analysis of the evolutionary mechanisms involved in their diversification.Here,we used Oxford Nanopore long-read technologyto sequence the diploid Chrysanthemum nankingense genome,which represents one of the progenitor genomes of domesticated chrysanthemums.Our analysis revealed that the evolution of the C.nankingense genome was driven by bursts of repetitive element expansion and WGD events including a recentWGD that distinguishes chrysanthemum from sunflower,which diverged from chrysanthemum approximately 38.8 million years ago.Variations of ornamental and medicinal traits in chrysanthemums are linked to the expansion of candidate gene families by duplication events including paralogous gene duplication.Collectively,our study of the assembled reference genome offers new knowledge and resources to dissect the history and pattern of evolution and diversification of chrysanthemum plants,and also to accelerate their breeding and improvement.展开更多
How to discover the trustworthy services is a challenge for potential users because of the deficiency of us- age experiences and the information overload of QoE （qual- ity of experience） evaluations from consumers. ...How to discover the trustworthy services is a challenge for potential users because of the deficiency of us- age experiences and the information overload of QoE （qual- ity of experience） evaluations from consumers. Aiming to the limitations of traditional interval numbers in measuring the trustworthiness of service, this paper proposed a novel ser- vice recommendation approach using the interval numbers of four parameters （INF） for potential users. In this approach, a trustworthiness cloud model was established to identify the eigenvalue of INF via backward cloud generator, and a new formula of INF possibility degree based on geometrical anal- ysis was presented to ensure the high calculation precision. In order to select the highly valuable QoE evaluations, the similarity of client-side feature between potential user and consumers was calculated, and the multi-attributes trustwor- thiness values were aggregated into INF by the fuzzy ana- lytic hierarchy process method. On the basis of ranking INF, the sort values of trustworthiness of candidate services were obtained, and the trustworthy services were chosen to recommend to potential user. The experiments based on a real-world dataset showed that it can improve the recommendation accuracy of trustworthy services compared to other approaches, which contributes to solving cold start and information overload problem in service recommendation.展开更多
Recently the developed single guide(sg)RNA-guided clustered regularly interspaced short palindromic repeats/associated protein 9 nuclease(CRISPR/Cas9) technology has opened a new avenue for antiviral therapy. The CRIS...Recently the developed single guide(sg)RNA-guided clustered regularly interspaced short palindromic repeats/associated protein 9 nuclease(CRISPR/Cas9) technology has opened a new avenue for antiviral therapy. The CRISPR/Cas9 system uniquely allows targeting of multiple genome sites simultaneously. However, there are relatively few applications of CRISPR/Cas9 multigene editing to target insect viruses. To address the need for sustained delivery of a multiplex CRISPR/Cas9-based genome-editing vehicle against insect viruses, we developed a one-vector(pSL1180-Cas9-U6-sgRNA) system that expresses multiple sgRNA and Cas9 protein to excise Bombyx mori nucleopolyhedrovirus(BmNPV) in insect cells.We screened the immediate-early-1 gene(ie-1), the major envelope glycoprotein gene(gp64), and the late expression factor gene(lef-11), and identified multiple sgRNA editing sites through flow cytometry and viral DNA replication analysis. In addition, we constructed a multiplex editing vector(PSL1180-Cas9-sgIE1-sgLEF11-sgGP64, sgMultiple) to efficiently regulate multiplex gene-editing and inhibit BmNPV replication after viral infection. This is the first report of the application of a multiplex CRISPR/Cas9 system to inhibit insect virus replication. This multiplex system can significantly enhance the potential of CRISPR/Cas9-based multiplex genome engineering in insect virus.展开更多
Protected areas are generally regarded as a power tool to conserve biodiversity.Nonetheless,few protected areas could address three crucial problems simultaneously,namely funding,public participation and rural living....Protected areas are generally regarded as a power tool to conserve biodiversity.Nonetheless,few protected areas could address three crucial problems simultaneously,namely funding,public participation and rural living.Here,we introduced a new protective approach,Natural Fostering,which integrated herbal medicine production with community conservation.The principles of Natural Fostering adopted species–species interaction at community level.Most effective chemical components of herbal medicine are derived from such interaction.Fritillaria cirrhosa was selected as an economic botany,one of herbal medicines,to carry out Natural Fostering.Community habitats,herbal medicine production,funding and income of local family were investigated to verify the feasibility of Natural Fostering for biodiversity.We found the density of plant populations and the annual average personal income of rural people increased.F.cirrhosa production could provide sufficient funds for sustainable conservation.Local people gradually changed their life style of wild collection and overgrazing,instead of herbal medicine production.The fostering area set up a good sustainable economic cycle.Natural Fostering can be presented as an effective and pragmatic way to conserve biological diversity and sustainable utilization of traditional medicinal resources.展开更多
The Precise Point Positioning(PPP)technique uses a single Global Navigation Satellite System(GNSS)receiver to collect carrier-phase and code observations and perform centimeter-accuracy positioning together with the p...The Precise Point Positioning(PPP)technique uses a single Global Navigation Satellite System(GNSS)receiver to collect carrier-phase and code observations and perform centimeter-accuracy positioning together with the precise satellite orbit and clock corrections provided.According to the observations used,there are basically two approaches,namely,the ionosphere-free combination approach and the raw observation approach.The former eliminates the ionosphere effects in the observation domain,while the latter estimates the ionosphere effects using uncombined and undifferenced observations,i.e.,so-called raw observations.These traditional techniques do not fix carrier-phase ambiguities to integers,if the additional corrections of satellite hardware biases are not provided to the users.To derive the corrections of hardware biases in network side,the ionosphere-free combination operation is often used to obtain the ionosphere-free ambiguities from the L1 and L2 ones produced even with the raw observation approach in earlier studies.This contribution introduces a variant of the raw observation approach that does not use any ionosphere-free(or narrow-lane)combination operator to derive satellite hardware bias and compute PPP ambiguity float and fixed solution.The reparameterization and the manipulation of design matrix coefficients are described.A computational procedure is developed to derive the satellite hardware biases on WL and L1 directly.The PPP ambiguity-fixed solutions are obtained also directly with WL/L1 integer ambiguity resolutions.The proposed method is applied to process the data of a GNSS network covering a large part of China.We produce the satellite biases of BeiDou,GPS and Galileo.The results demonstrate that both accuracy and convergence are significantly improved with integer ambiguity resolution.The BeiDou contributions on accuracy and convergence are also assessed.It is disclosed for the first time that BeiDou only ambiguity-fixed solutions achieve the similar accuracy with that of GPS/Galileo combined,at least in China's Mainland.The numerical analysis demonstrates that the best solutions are achieved by GPS/Galileo/BeiDou solutions.The accuracy in horizontal components is better than 6 mm,and in the height component better than 20 mm(one sigma).The mean convergence time for reliable ambiguity-fixing is about 1.37 min with 0.12 min standard deviation among stations without using ionosphere corrections and the third frequency measurements.The contribution of BDS is numerically highlighted.展开更多
基金supported by the National Natural Science Foundation of China,No.82101461(to ZL)。
文摘Central nervous system injuries have a high rate of resulting in disability and mortality;however,at present,effective treatments are lacking.Programmed cell death,which is a genetically determined fo rm of active and ordered cell death with many types,has recently attra cted increasing attention due to its functions in determining the fate of cell survival.A growing number of studies have suggested that programmed cell death is involved in central nervous system injuries and plays an important role in the progression of brain damage.In this review,we provide an ove rview of the role of programmed cell death in central nervous system injuries,including the pathways involved in mitophagy,pyroptosis,ferroptosis,and necroptosis,and the underlying mechanisms by which mitophagy regulates pyroptosis,ferroptosis,and necro ptosis.We also discuss the new direction of therapeutic strategies to rgeting mitophagy for the treatment of central nervous system injuries,with the aim to determine the connection between programmed cell death and central nervous system injuries and to identify new therapies to modulate programmed cell death following central nervous system injury.In conclusion,based on these properties and effects,interventions targeting programmed cell death could be developed as potential therapeutic agents for central nervous system injury patients.
基金the support from the National Natural Science Foundation(No.52171186)National Key Research&Development Program(2022YFB3803700)of China.
文摘Hydrogen holds the advantages of high energy density,great natural abundance and zero emission,making it suitable for large scale and long term energy storage,while its safe and efficient storage is still challenging.Among various solid state hydrogen storage materials,MgH_(2) is promising for industrial applications due to its high gravimetric and volumetric hydrogen densities and the abundance of Mg on earth.However,the practical application of MgH_(2) has been limited by its stable thermodynamics and slow hydrogen desorption kinetics.Nanocatalysis is considered as a promising approach for improving the hydrogen storage performance of MgH_(2) and bringing it closer to the requirements of commercial applications.It is worth mentioning that the recently emerging two-dimensional material,MXene,has showcased exceptional catalytic abilities in modifying the hydrogen storage properties of MgH_(2).Besides,MXene possesses a high surface area,excellent chemical/physical stability,and negatively charged terminating groups,making it an ideal support for the"nanoconfinement"of MgH_(2) or highly active catalysts.Herein,we endeavor to provide a comprehensive overview of recent investigations on MXene-based catalysts and MXene supports for improving the hydrogen sorption properties of Mg/MgH_(2).The mechanisms of hydrogen sorption involved in Mg-MXene based composites are highlighted with special emphases on thermodynamics,kinetics,and catalytic behaviors.The aim of this work is to provide a comprehensive and objective review of researches on the development of high-performance catalysts/supports to improve hydrogen storage performances of Mg/MgH_(2) and to identify the opportunities and challenges for future applications.
基金National Natural Science Foundation of China(Nos.42030109,42074032)Program for Hubei Provincial Science and Technology Innovation Talants(No.2022EJD010)。
文摘As one of the Analysis Centers(AC)of the International GNSS Service(IGS),Wuhan University(WHU)has been contributing to the IGS by providing ultra-rapid as well as rapid orbit and clock solutions for the established GPS and GLONASS since 2012.In the same year,the IGS initiated the Multi-GNSS Experiment(MGEX)to support the analysis of the emerging GNSS systems and prepare the IGS for Multi-GNSS,which includes GPS,GLONASS,the European Galileo system,the Chinese Beidou Navigation Satellite System(BDS),the Japanese Quasi-Zenith Satellite System(QZSS)and the Indian Regional Navigation Satellite System(IRNSS/NaVIC).The major products,i.e.,orbits,Earth Orientation Parameters(EOPs),satellite clock as well as attitude have also been provided by WHU since 2012.More recently,WHU has engaged the third reprocessing of IGS for generating the highly accurate station coordinates as inputs for establishment of the International Terrestrial Reference Frame(ITRF)2020 during 2019—2020.This article presents the recent major advancements of the IGS AC at Wuhan University,including precise products,real-time products,bias products,antenna phase center calibration,and the non-linear motion modeling for GNSS Reference Stations.
文摘Objective: To develop a kind self active resistance movement training equipment for cervical spine, so as to restore the dynamic balance of the front and back muscle strength of the cervical spine in order to correct the abnormal physiological radian of the cervical spine, thereby relieving the clinical symptoms. Methods: The air spring with adjustable strength was used to provide the power of resistance active movement, and the neurological training cervical audio-visual synthesis training software was used to automatically guide patients to perform resistance active movement training of the cervical spine. Thirty two patients with cervical spondylosis were enrolled for treatment, and SPSS26 was used to statistically analyze the VAS, Lovett muscle strength, head and neck range of motion and C2-3 vertebral body curvature before and after the treatment. Result: There were significant differences in posterior cervical muscle strength (Lovett), dizziness, shoulder and neck pain (VAS) and C2-3 vertebral curvature before and after training in 32 patients (p˂0.001). Conclusion: The application of neurological training cervical vertebra self rehabilitation training instrument can effectively relieve clinical symptoms, restore head and neck range of motion, improve nape muscle strength, restore the dynamic balance of front and rear cervical muscle strength, and also can correct the abnormal physiological radian of the cervical vertebra.
基金supported in part by National Natural Science Foundation of China(61272148,61572525,61502056,and 61602525)Hunan Provincial Natural Science Foundation of China(2015JJ3010)Scientific Research Fund of Hunan Provincial Education Department(15B009,14C0285)
文摘The growing trend of network virtualization results in a widespread adoption of virtual switches in virtualized environments. However, virtual switching is confronted with great performance challenges regarding packet classification especially in Open Flow-based software defined networks. This paper first takes an insight into packet classification in virtual Open Flow switching, and points out that its performance bottleneck is dominated by flow table traversals of multiple failed mask probing for each arrived packet. Then we are motivated to propose an efficient packet classification algorithm based on counting bloom filters. In particular, counting bloom filters are applied to predict the failures of flow table lookups with great possibilities, and bypass flow table traversals for failed mask probing. Finally, our proposed packet classification algorithm is evaluated with real network traffic traces by experiments. The experimental results indicate that our proposed algorithm outperforms the classical one in Open v Switch in terms of average search length, and contributes to promote virtual Open Flow switching performance.
基金supported by the National Social Science Foundation of China (Grant No.: 14BTQ030)
文摘Purpose： In this paper, we combined the method of co-word analysis and alluvial diagram to detect hot topics and illustrate their dynamics. Design/methodology/approach： Articles in the field of scientometrics were chosen as research cases in this study. A time-sliced co-word network was generated and then clustered. Afterwards, we generated an alluvial diagram to show dynamic changes of hot topics, including their merges and splits over time. Findings： After analyzing the dynamic changes in the field of scientometrics from 2011 to 2015, we found that two clusters being merged did not mean that the old topics had disappeared and a totally new one had emerged. The topics were possibly still active the following year, but the newer topics had drawn more attention. The changes of hot topics reflected the shift in researchers＇ interests. subdivided and re-merged. For example, several topics as research progressed. Research topics in scientometrics were constantly a cluster involving ＂industry＂ was divided into Research limitations： When examining longer time periods, we encounter the problem of dealing with bigger data sets. Analyzing data year by year would be tedious, but if we combine, e.g. two years into one time slice, important details would be missed. Practical implications： This method can be applied to any research field to illustrate the dynamics of hot topics. It can indicate the promising directions for researchers and provide guidance to decision makers. Originality/value： The use of alluvial diagrams is a distinctive and meaningful approach to detecting hot topics and especially to illustrating their dynamics.
基金supported by the National Social Science Foundation of China(Grant No.:14BTQ030)
文摘Purpose： Research fronts build on recent work, but using times cited as a traditional indicator to detect research fronts will inevitably result in a certain time lag. This study attempts to explore the effects of usage count as a new indicator to detect research fronts in shortening the time lag of classic indicators in research fronts detection. Design/methodology/approach： An exploratory study was conducted where the new indicator ＂usage count＂ was compared to the traditional citation count, ＂times cited,＂ in detecting research fronts of the regenerative medicine domain. An initial topic search of the term ＂regenerative medicine＂ returned 10,553 records published between 2000 and 2015 in the Web of Science （WoS）. We first ranked these records with usage count and times cited, respectively, and selected the top 2,000 records for each. We then performed a co-citation analysis in order to obtain the citing papers of the co-citation clusters as the research fronts. Finally, we compared the average publication year of the citing papers as well as the mean cited year of the co-citation clusters. Findings： The citing articles detected by usage count tend to be published more recently compared with times cited within the same research front. Moreover, research fronts detected by usage count tend to be within the last two years, which presents a higher immediacy and real-time feature compared to times cited. There is approximately a three-year time span among the mean cited years （known as ＂intellectual base＂） of all clusters generated by usage count and this figure is about four years in the network of times cited. In comparison to times cited, usage count is a dynamic and instant indicator. Research limitations： We are trying to find the cutting-edge research fronts, but those generated based on co-citations may refer to the hot research fronts. The usage count of older highly cited papers was not taken into consideration, because the usage count indicator released by WoS only reflects usage logs after February 2013. Practical implications： The article provides a new perspective on using usage count as a new indicator to detect research fronts.Originality/value： Usage count can greatly shorten the time lag in research fronts detection, which would be a promising complementary indicator in detection of the latest research fronts.
基金the National Natural Science Foundation of China(No.61602525,No.61572525)the Research Foundation of Education Bureau of Hunan Province of China(No.19C1391)the Natural Science Foundation of Hunan Province of China(No.2020JJ5775)。
文摘With the number of connected devices increasing rapidly,the access latency issue increases drastically in the edge cloud environment.Massive low time-constrained and data-intensive mobile applications require efficient replication strategies to decrease retrieval time.However,the determination of replicas is not reasonable in many previous works,which incurs high response delay.To this end,a correlation-aware replica prefetching(CRP)strategy based on the file correlation principle is proposed,which can prefetch the files with high access probability.The key is to determine and obtain the implicit high-value files effectively,which has a significant impact on the performance of CRP.To achieve the goal of accelerating the acquisition of implicit highvalue files,an access rule management method based on consistent hashing is proposed,and then the storage and query mechanisms for access rules based on adjacency list storage structure are further presented.The theoretical analysis and simulation results corroborate that CRP shortens average response time over 4.8%,improves average hit ratio over 4.2%,reduces transmitting data amount over 8.3%,and maintains replication frequency at a reasonable level when compared to other schemes.
文摘Data-intensive computing is expected to be the next-generation IT computing paradigm. Data-intensive workflows in clouds are becoming more and more popular. How to schedule data-intensive workflow efficiently has become the key issue. In this paper, first, we build a directed hypergraph model for data-intensive workflow, since Hypergraphs can more accurately model communication volume and better represent asymmetric problems, and the cut metric of hypergraphs is well suited for minimizing the total volume of communication.Second, we propose a concept data supportive ability to help the presentation of data-intensive workflow application and provide the merge operation details considering the data supportive ability. Third, we present an optimized hypergraph multi-level partitioning algorithm. Finally we bring a data reduced scheduling policy HEFT-P for data-intensive workflow. Through simulation,we compare HEFT-P with three typical workflow scheduling policies.The results indicate that HEFT-P could obtain reduced data scheduling and reduce the makespan of executing data-intensive
文摘The number of Internet Web services has become increasingly large recently.Cloud services consumers face a critical challenge in selecting services from abundant candidates.Due to the uncertainty of Web service QoS and the diversity of user characteristics,this paper proposes a Web service recommendation method based on cloud model and user personality(WSRCP),which employs cloud model similarity method to analyze the similarity of QoS feedback data among different users,to identify the user with high similarity to the potential user.Based on the QoS data of the users’feedback,Finally,user characteristic attribute Web service recommendation is implemented by personalized collaborative filtering algorithm.The experimental results on the WS-Dream dataset show that our approach not only solves the drawbacks of the sparse user service,but also improves the recommend accuracy.
基金National Natural Science Foundation(No.52171186)The authors also appreciate the financial support from China Minmetals Corporation and the Center of Hydrogen Science,Shanghai Jiao Tong University,China.
文摘Achieving dual regulation of the kinetics and thermodynamics of MgH_(2) is essential for the practical applications.In this study,a novel nanocomposite(In@Ti-MX)architected from single-/few-layered Ti_(3)C_(2) MXenes and ultradispersed indium nanoparticles was prepared by a bottom-up self-assembly strategy and introduced into MgH_(2) to solve the above-mentioned problems.The MgH_(2)+In@Ti-MX composites demonstrate excellent hydrogen storage performance:The resultant In@Ti-MX demonstrated a positive effect on the hydrogen storage performance of MgH_(2)/Mg:the dehydrogenated rate of MgH_(2)+15 wt%In@Ti-MX reached the maximum at 330°C,which was 47°C lower than that of commercial MgH_(2);The hydrogenation enthalpy of the dehydrided MgH_(2)+15 wt%In@Ti-MX and MgH_(2)+25 wt%In@Ti-MX were determined to be−66.2±1.1 and−61.7±1.4 kJ·mol^(−1) H_(2).In situ high-energy synchrotron x-ray diffraction technique together with other microstructure analyses revealed that synergistic effects from Ti_(3)C_(2) MXenes and In nanoparticles(NPs)contributed to the improved kinetics and thermodynamics of MgH_(2)(Mg):Ti/TiH_(2) derived from Ti_(3)C_(2) MXenes accelerated the dissociation and recombination of hydrogen molecule/atoms,while In NPs reduced the thermodynamic stability of MgH_(2) by forming the Mg-In solution.Such a strategy of using dual-active hybrid structures to modify MgH_(2)/Mg provides a new insight for tuning both the hydrogen storage kinetics and thermodynamics of Mg-based hydrides.
基金supported by grants from the National Natural Science Foundation of China,China(Nos.81870397,82000534,and 82073156)Shenzhen Kangzhe Pharmaceutical Co.Ltd,China(URC-126/PBC)+1 种基金The Fifth Suzhou Health Talent Project(GSWS201903)The Suzhou Radiotherapy Clinical Medical Center Project,Suzhou,Jiangsu,China(Szlcyxzx202103).
文摘Primary biliary cholangitis(PBC)is an autoimmune liver disease characterized by the destruction of intrahepatic small bile ducts and progressive cholestasis,eventually leading to liver cirrhosis and hepatic failure without appropriate treatment(Terziroli Beretta-Piccoli et al.,2019).
基金The National Key Research and Development Program of China (2016YFD0801102)and the National Natural Science Foundation of China (31870198 and 31400278).
文摘The Asteraceae (Compositae),a large plant family of approximately 24 000-35 000 species,accounts for^10% of all angiosperm species and contributes a lot to plant diversity.The most representative members of the Asteraceae are the economically important chrysanthemums (Chrysanthemum L.)that diversified through reticulate evolution.Biodiversity is typically created by multiple evolutionary mechanisms such as wholegenome duplication 0NGD)or polyploidization and locally repetitive genome expansion.However,the lack of genomic data from chrysanthemum species has prevented an in-depth analysis of the evolutionary mechanisms involved in their diversification.Here,we used Oxford Nanopore long-read technologyto sequence the diploid Chrysanthemum nankingense genome,which represents one of the progenitor genomes of domesticated chrysanthemums.Our analysis revealed that the evolution of the C.nankingense genome was driven by bursts of repetitive element expansion and WGD events including a recentWGD that distinguishes chrysanthemum from sunflower,which diverged from chrysanthemum approximately 38.8 million years ago.Variations of ornamental and medicinal traits in chrysanthemums are linked to the expansion of candidate gene families by duplication events including paralogous gene duplication.Collectively,our study of the assembled reference genome offers new knowledge and resources to dissect the history and pattern of evolution and diversification of chrysanthemum plants,and also to accelerate their breeding and improvement.
文摘How to discover the trustworthy services is a challenge for potential users because of the deficiency of us- age experiences and the information overload of QoE （qual- ity of experience） evaluations from consumers. Aiming to the limitations of traditional interval numbers in measuring the trustworthiness of service, this paper proposed a novel ser- vice recommendation approach using the interval numbers of four parameters （INF） for potential users. In this approach, a trustworthiness cloud model was established to identify the eigenvalue of INF via backward cloud generator, and a new formula of INF possibility degree based on geometrical anal- ysis was presented to ensure the high calculation precision. In order to select the highly valuable QoE evaluations, the similarity of client-side feature between potential user and consumers was calculated, and the multi-attributes trustwor- thiness values were aggregated into INF by the fuzzy ana- lytic hierarchy process method. On the basis of ranking INF, the sort values of trustworthiness of candidate services were obtained, and the trustworthy services were chosen to recommend to potential user. The experiments based on a real-world dataset showed that it can improve the recommendation accuracy of trustworthy services compared to other approaches, which contributes to solving cold start and information overload problem in service recommendation.
基金supported by grants from the National Natural Science Foundation of China (Nos. 31872427 and 31572466)China Agriculture Research System (CARS-18)+1 种基金Chongqing Special Postdoctoral Science Foundation (XmT2018020)China Postdoctoral Science Foundation (2018M633309)
文摘Recently the developed single guide(sg)RNA-guided clustered regularly interspaced short palindromic repeats/associated protein 9 nuclease(CRISPR/Cas9) technology has opened a new avenue for antiviral therapy. The CRISPR/Cas9 system uniquely allows targeting of multiple genome sites simultaneously. However, there are relatively few applications of CRISPR/Cas9 multigene editing to target insect viruses. To address the need for sustained delivery of a multiplex CRISPR/Cas9-based genome-editing vehicle against insect viruses, we developed a one-vector(pSL1180-Cas9-U6-sgRNA) system that expresses multiple sgRNA and Cas9 protein to excise Bombyx mori nucleopolyhedrovirus(BmNPV) in insect cells.We screened the immediate-early-1 gene(ie-1), the major envelope glycoprotein gene(gp64), and the late expression factor gene(lef-11), and identified multiple sgRNA editing sites through flow cytometry and viral DNA replication analysis. In addition, we constructed a multiplex editing vector(PSL1180-Cas9-sgIE1-sgLEF11-sgGP64, sgMultiple) to efficiently regulate multiplex gene-editing and inhibit BmNPV replication after viral infection. This is the first report of the application of a multiplex CRISPR/Cas9 system to inhibit insect virus replication. This multiplex system can significantly enhance the potential of CRISPR/Cas9-based multiplex genome engineering in insect virus.
基金The study was funded by the National Natural Science Foundation of China(Grant No.30572324 and 81130069).
文摘Protected areas are generally regarded as a power tool to conserve biodiversity.Nonetheless,few protected areas could address three crucial problems simultaneously,namely funding,public participation and rural living.Here,we introduced a new protective approach,Natural Fostering,which integrated herbal medicine production with community conservation.The principles of Natural Fostering adopted species–species interaction at community level.Most effective chemical components of herbal medicine are derived from such interaction.Fritillaria cirrhosa was selected as an economic botany,one of herbal medicines,to carry out Natural Fostering.Community habitats,herbal medicine production,funding and income of local family were investigated to verify the feasibility of Natural Fostering for biodiversity.We found the density of plant populations and the annual average personal income of rural people increased.F.cirrhosa production could provide sufficient funds for sustainable conservation.Local people gradually changed their life style of wild collection and overgrazing,instead of herbal medicine production.The fostering area set up a good sustainable economic cycle.Natural Fostering can be presented as an effective and pragmatic way to conserve biological diversity and sustainable utilization of traditional medicinal resources.
基金the National Natural Science Foundation of China(Grant Nos.42030109).The support is gratefully acknowledged.
文摘The Precise Point Positioning(PPP)technique uses a single Global Navigation Satellite System(GNSS)receiver to collect carrier-phase and code observations and perform centimeter-accuracy positioning together with the precise satellite orbit and clock corrections provided.According to the observations used,there are basically two approaches,namely,the ionosphere-free combination approach and the raw observation approach.The former eliminates the ionosphere effects in the observation domain,while the latter estimates the ionosphere effects using uncombined and undifferenced observations,i.e.,so-called raw observations.These traditional techniques do not fix carrier-phase ambiguities to integers,if the additional corrections of satellite hardware biases are not provided to the users.To derive the corrections of hardware biases in network side,the ionosphere-free combination operation is often used to obtain the ionosphere-free ambiguities from the L1 and L2 ones produced even with the raw observation approach in earlier studies.This contribution introduces a variant of the raw observation approach that does not use any ionosphere-free(or narrow-lane)combination operator to derive satellite hardware bias and compute PPP ambiguity float and fixed solution.The reparameterization and the manipulation of design matrix coefficients are described.A computational procedure is developed to derive the satellite hardware biases on WL and L1 directly.The PPP ambiguity-fixed solutions are obtained also directly with WL/L1 integer ambiguity resolutions.The proposed method is applied to process the data of a GNSS network covering a large part of China.We produce the satellite biases of BeiDou,GPS and Galileo.The results demonstrate that both accuracy and convergence are significantly improved with integer ambiguity resolution.The BeiDou contributions on accuracy and convergence are also assessed.It is disclosed for the first time that BeiDou only ambiguity-fixed solutions achieve the similar accuracy with that of GPS/Galileo combined,at least in China's Mainland.The numerical analysis demonstrates that the best solutions are achieved by GPS/Galileo/BeiDou solutions.The accuracy in horizontal components is better than 6 mm,and in the height component better than 20 mm(one sigma).The mean convergence time for reliable ambiguity-fixing is about 1.37 min with 0.12 min standard deviation among stations without using ionosphere corrections and the third frequency measurements.The contribution of BDS is numerically highlighted.
