Land use reflects human activities on land.Urban land use is the highest level human alteration on Earth,and it is rapidly changing due to population increase and urbanization.Urban areas have widespread effects on lo...Land use reflects human activities on land.Urban land use is the highest level human alteration on Earth,and it is rapidly changing due to population increase and urbanization.Urban areas have widespread effects on local hydrology,climate,biodiversity,and food production[1,2].However,maps,that contain knowledge on the distribution,pattern and composition of various land use types in urban areas,are limited to city level.The mapping standard on data sources,methods,land use classification schemes varies from city to city,due to differences in financial input and skills of mapping personnel.To address various national and global environmental challenges caused by urbanization,it is important to have urban land uses at the national and global scales that are derived from the same or consistent data sources with the same or compatible classification systems and mapping methods.This is because,only with urban land use maps produced with similar criteria,consistent environmental policies can be made,and action efforts can be compared and assessed for large scale environmental administration.However,despite of the fact that a number of urban-extent maps exist at global scales[3,4],more detailed urban land use maps do not exist at the same scale.Even at big country or regional levels such as for the United States,China and European Union,consistent land use mapping efforts are rare[5,6](e.g.,https://sdi4apps.eu/open_land_use/).展开更多
The FAIR principles have been widely cited,endorsed and adopted by a broad range of stakeholders since their publication in 2016.By intention,the 15 FAIR guiding principles do not dictate specific technological implem...The FAIR principles have been widely cited,endorsed and adopted by a broad range of stakeholders since their publication in 2016.By intention,the 15 FAIR guiding principles do not dictate specific technological implementations,but provide guidance for improving Findability,Accessibility,Interoperability and Reusability of digital resources.This has likely contributed to the broad adoption of the FAIR principles,because individual stakeholder communities can implement their own FAIR solutions.However,it has also resulted in inconsistent interpretations that carry the risk of leading to incompatible implementations.Thus,while the FAIR principles are formulated on a high level and may be interpreted and implemented in different ways,for true interoperability we need to support convergence in implementation choices that are widely accessible and(re)-usable.We introduce the concept of FAIR implementation considerations to assist accelerated global participation and convergence towards accessible,robust,widespread and consistent FAIR implementations.Any self-identified stakeholder community may either choose to reuse solutions from existing implementations,or when they spot a gap,accept the challenge to create the needed solution,which,ideally,can be used again by other communities in the future.Here,we provide interpretations and implementation considerations(choices and challenges)for each FAIR principle.展开更多
During the years 2006–2009,lakes in the Qinghai-Tibetan Plateau(QTP)were investigated using satellite remote sensing strategies.We report the results of this investigation as well as follow-up research and expanded w...During the years 2006–2009,lakes in the Qinghai-Tibetan Plateau(QTP)were investigated using satellite remote sensing strategies.We report the results of this investigation as well as follow-up research and expanded work.For the investigation,we mainly focused on lakes whose areas are more than 1 km2.The remote sensing data that we used included 408 scenes of CBERS CCD images and 5 scenes of Landsat ETM?images in Qinghai Province and Tibet Autonomous Region.All these data were acquired around years 2005–2006.Besides remote sensing images,we also collected 1,259 topographic maps.Numbers and areas of lakes were analyzed statistically,which were then compared with those coming from the first lake investigation(implemented between the1960s and 1980s).According to our investigation,up to and around year 2005–2006,the total number of lakes in the QTP was 1,055(222 in Qinghai and 833 in Tibet),accounting for more than 30%of that of China.Thirty newborn lakes with area[1 km2were found,and 5 dead lakes with initial area[1 km2were also found.Among those 13 big lakes([500 km2),Yamzhog Yumco had seriously shrunk,and it has continued to shrink in recent years;Qinghai Lake had shrunk during the period,but some new researches indicated that it has been expanding since the year 2004;Siling Co,Nam Co,and Chibuzhang Co had expanded in the period.We divided the newborn lakes into six categories according to their forming reasons,including river expansion,wetland conversion,etc.The changes of natural conditions led to the death of four lakes,and human exploitation was the main reason for the death of Dalianhai Lake in Qinghai.We picked out three regions which were sensitive to the change of climate and ecological environment:Nagqu Region,Kekexili Region,and the source area of the Yellow River(SAYR).Lakes in both Nagqu and Kekexili have been expanded;meanwhile,most lakes in the SAYR have obviously been shrunk.These regional patterns of lake changes were highly related to variations of temperature,glacier,precipitation,and evapor展开更多
Highly accurate observations at various scales on the land surface are urgently needed for the studies of many areas,such as hydrology,meteorology,and agriculture.With the rapid development of remote sensing technique...Highly accurate observations at various scales on the land surface are urgently needed for the studies of many areas,such as hydrology,meteorology,and agriculture.With the rapid development of remote sensing techniques,remote sensing has had the capacity of monitoring many factors of the Earth's land surface.Especially,the space-borne microwave remote sensing systems have been widely used in the quantitative monitoring of global snow,soil moisture,and vegetation parameters with their all-weather,all-time observation capabilities and their sensitivities to the characteristics of land surface factors.Based on the electromagnetic theories and microwave radiative transfer equations,researchers have achieved great successes in the microwave remote sensing studies for different sensors in recent years.This article has systematically reviewed the progresses on five research areas including microwave theoretical modeling,microwave inversion on soil moisture,snow,vegetation and land surface temperatures.Through the further enrichment of remote sensing datasets and the development of remote sensing theories and inversion techniques,remote sensing including microwave remote sensing will play a more important role in the studies and applications of the Earth systems.展开更多
This study presents a general outline of the Qitai radio telescope(QTT)project.Qitai,the site of the telescope,is a county of Xinjiang Uygur Autonomous Region of China,located in the east Tianshan Mountains at an elev...This study presents a general outline of the Qitai radio telescope(QTT)project.Qitai,the site of the telescope,is a county of Xinjiang Uygur Autonomous Region of China,located in the east Tianshan Mountains at an elevation of about 1800 m.The QTT is a fully steerable,Gregorian-type telescope with a standard parabolic main reflector of 110 m diameter.The QTT has adopted an umbrella support,homology-symmetric lightweight design.The main reflector is active so that the deformation caused by gravity can be corrected.The structural design aims to ultimately allow high-sensitivity observations from 150 MHz up to115 GHz.To satisfy the requirements for early scientific goals,the QTTwill be equipped with ultra-wideband receivers and large field-of-view multi-beam receivers.A multi-function signal-processing system based on RFSo C and GPU processor chips will be developed.These will enable the QTT to operate in pulsar,spectral line,continuum and Very Long Baseline Interferometer(VLBI)observing modes.Electromagnetic compatibility(EMC)and radio frequency interference(RFI)control techniques are adopted throughout the system design.The QTT will form a world-class observational platform for the detection of lowfrequency(nano Hertz)gravitational waves through pulsar timing array(PTA)techniques,pulsar surveys,the discovery of binary black-hole systems,and exploring dark matter and the origin of life in the universe.The QTT will also play an important role in improving the Chinese and international VLBI networks,allowing high-sensitivity and high-resolution observations of the nuclei of distant galaxies and gravitational lensing systems.Deep astrometric observations will also contribute to improving the accuracy of the celestial reference frame.Potentially,the QTT will be able to support future space activities such as planetary exploration in the solar system and to contribute to the search for extraterrestrial intelligence.展开更多
The article introduces a new method for three-dimensional reproduction of edentulous dental casts,and wax occlusion rims with jaw relation by using a commercial high-speed line laser scanner and reverse engineering so...The article introduces a new method for three-dimensional reproduction of edentulous dental casts,and wax occlusion rims with jaw relation by using a commercial high-speed line laser scanner and reverse engineering software and evaluates the method’s accuracy in vitro.The method comprises three main steps：（i）acquisition of the three-dimensional stereolithography data of maxillary and mandibular edentulous dental casts and wax occlusion rims;（ii）acquisition of the three-dimensional stereolithography data of jaw relations;and（iii）registration of these data with the reverse engineering software and completing reconstruction.To evaluate the accuracy of this method,dental casts and wax occlusion rims of 10 edentulous patients were used.The lengths of eight lines between common anatomic landmarks were measured directly on the casts and occlusion rims by using a vernier caliper and on the three-dimensional computerized images by using the software measurement tool.The direct data were considered as the true values.The paired-samples t-test was used for statistical analysis.The mean differences between the direct and the computerized measurements were mostly less than 0.04 mm and were not significant（P.0.05）.Statistical significance among 10 patients was assessed using one-way analysis of variance（P,0.05）.The result showed that the 10 patients were considered statistically no significant.Therefore,accurate three-dimensional reproduction of the edentulous dental casts,wax occlusion rims,and jaw relations was achieved.The proposed method enables the visualization of occlusion from different views and would help to meet the demand for the computer-aided design of removable complete dentures.展开更多
This paper introduces an intelligent framework for predicting the advancing speed during earth pressure balance(EPB)shield tunnelling.Five artificial intelligence(AI)models based on machine and deep learning technique...This paper introduces an intelligent framework for predicting the advancing speed during earth pressure balance(EPB)shield tunnelling.Five artificial intelligence(AI)models based on machine and deep learning techniques-back-propagation neural network(BPNN),extreme learning machine(ELM),support vector machine(SVM),long-short term memory(LSTM),and gated recurrent unit(GRU)-are used.Five geological and nine operational parameters that influence the advancing speed are considered.A field case of shield tunnelling in Shenzhen City,China is analyzed using the developed models.A total of 1000 field datasets are adopted to establish intelligent models.The prediction performance of the five models is ranked as GRU>LSTM>SVM>ELM>BPNN.Moreover,the Pearson correlation coefficient(PCC)is adopted for sensitivity analysis.The results reveal that the main thrust(MT),penetration(P),foam volume(FV),and grouting volume(GV)have strong correlations with advancing speed(AS).An empirical formula is constructed based on the high-correlation influential factors and their corresponding field datasets.Finally,the prediction performances of the intelligent models and the empirical method are compared.The results reveal that all the intelligent models perform better than the empirical method.展开更多
Vehicle re-identification(ReID)aims to retrieve the target vehicle in an extensive image gallery through its appearances from various views in the cross-camera scenario.It has gradually become a core technology of int...Vehicle re-identification(ReID)aims to retrieve the target vehicle in an extensive image gallery through its appearances from various views in the cross-camera scenario.It has gradually become a core technology of intelligent transportation system.Most existing vehicle re-identification models adopt the joint learning of global and local features.However,they directly use the extracted global features,resulting in insufficient feature expression.Moreover,local features are primarily obtained through advanced annotation and complex attention mechanisms,which require additional costs.To solve this issue,a multi-feature learning model with enhanced local attention for vehicle re-identification(MFELA)is proposed in this paper.The model consists of global and local branches.The global branch utilizes both middle and highlevel semantic features of ResNet50 to enhance the global representation capability.In addition,multi-scale pooling operations are used to obtain multiscale information.While the local branch utilizes the proposed Region Batch Dropblock(RBD),which encourages the model to learn discriminative features for different local regions and simultaneously drops corresponding same areas randomly in a batch during training to enhance the attention to local regions.Then features from both branches are combined to provide a more comprehensive and distinctive feature representation.Extensive experiments on VeRi-776 and VehicleID datasets prove that our method has excellent performance.展开更多
Macrophage-mediated inflammation compromises bone repair in diabetic patients.Electrical signaling cues are known to regulate macrophage functions.However,the biological effects of electrical microenvironment from cha...Macrophage-mediated inflammation compromises bone repair in diabetic patients.Electrical signaling cues are known to regulate macrophage functions.However,the biological effects of electrical microenvironment from charged biomaterials on the immune response for regulating osteogenesis under diabetic conditions remain to be elucidated.Herein the endogeneous electrical microenvironment of native bone tissue was recapitulated by fabricating a ferroelectric BaTiO_(3)/poly(vinylidene fluoridetrifluoroethylene)(BTO/P(VDF-TrFE))nanocomposite membrane.In vitro,the polarized BaTiO_(3)/poly(vinylidene fluoridetrifluoroethylene)(BTO/P(VDF-TrFE))nanocomposite membranes inhibited high glucose-induced M1-type inflammation,by effecting changes in cell morphology,M1 marker expression and pro-inflammatory cytokine secretion in macrophages.This led to enhanced osteogenic differentiation of human bone marrow mesenchymal stem cells(BM-MSCs).In vivo,the biomimetic electrical microenvironment recapitulated by the polarized nanocomposite membranes switched macrophage phenotype from the pro-inflammatory(M1)into the pro-healing(M2)phenotype,which in turn enhanced bone regeneration in rats with type 2 diabetes mellitus.Mechanistic studies revealed that the biomimetic electrical microenvironment attenuated pro-inflammatory M1 macrophage polarization under hyperglycemic conditions by suppressing expression of AKT2 and IRF5 within the PI3K-AKT signaling pathway,thereby inducing favorable osteo-immunomodulatory effects.Our study thus provides fundamental insights into the biological effects of restoring the electrical microenvironment conducive for osteogenesis under DM conditions,and offers an effective strategy to design functionalized biomaterials for bone regeneration therapy in diabetic patients.展开更多
Due to the advantages of large workspace,low cost and the integrated vision/force sensing,robotic milling has become an important way for machining of complex parts.In recent years,many scholars have studied the probl...Due to the advantages of large workspace,low cost and the integrated vision/force sensing,robotic milling has become an important way for machining of complex parts.In recent years,many scholars have studied the problems existing in the applications of robotic milling,and lots of results have been made in the dynamics,pose planning,deformation control etc.,which provides theoretical guidance for high precision and high efficiency of robotic milling.From the perspective of complex parts robotic milling,this paper focuses on machining process planning and control techniques including the analysis of the robot-workspace,robot trajectory planning,vibration monitoring and control,deformation monitoring and compensation.As well as the principles of these technologies such as robot stiffness characteristics,dynamic characteristics,chatter mechanisms,and deformation mechanisms.The methods and characteristics related to the theory and technology of robotic milling of complex parts are summarized systematically.The latest research progress and achievements in the relevant fields are reviewed.It is hoped that the challenges,strategies and development related to robotic milling could be clarified through the carding work in this paper,so as to promote the application of related theories and technologies in high efficiency and precision intelligent milling with robot for complex parts.展开更多
Urban agglomerations are spatial entities that promote the development of ‘new urbanization' processes within China. In this context, the concept of ‘multiscale urban agglomeration spaces' encompasses three ...Urban agglomerations are spatial entities that promote the development of ‘new urbanization' processes within China. In this context, the concept of ‘multiscale urban agglomeration spaces' encompasses three linked levels: macroscale urban agglomerations, mesoscale cities, and microscale urban centers. Applying a series of multidisciplinary integrated research methods drawn from geography, urban planning, and architecture, this paper reveals two intensive utilization laws that can be generalized to apply to multiscale urban agglomeration spaces, top-to-bottom ‘positive transmission' linkage and inside-to-outside ‘negative transmission' movement. This paper also proposes optimization transmission theory and policy decision technical pathways that can be applied to these three urban agglomeration spatial scales. Specific technical pathways of transmission include intensive expansion and simulated decision-making in macroscale urban agglomerations, ecology, production, and living space intensive layout and dynamic decision-making in mesoscale cities, and four cores(i.e., ‘single, ring, axis, and pole core') progressive linkage and intensive optimization decision-making in microscale urban centers. The theory and technical pathways proposed in this paper solve the technical problem of optimization and provide intensive methods that can be applied not only at the individual level but also at multiple scales in urban agglomeration spaces. This study also advances a series of comprehensive technical solutions that can be applied to both compact and smart growth cities as well as to urban agglomerations. Solid theoretical support is provided for the optimization of Chinese land development, urbanization, agricultural development, and ecological security.展开更多
Based on the temporal-spatial distribution features of ancient settlement sites from the middle and late Neolithic Age to the Han dynasty in the Chaohu Lake Basin of Anhui Province, East China, using the methods of GI...Based on the temporal-spatial distribution features of ancient settlement sites from the middle and late Neolithic Age to the Han dynasty in the Chaohu Lake Basin of Anhui Province, East China, using the methods of GIS combined with the reconstructed paleoen- vironment by the records of lake sediment since Holocene, the transmutation of ancient set- tlements with response to environmental changes in this area has been discussed. Studies show that the main feature of transmutation of ancient settlements from the middle and late Neolithic Age to the Han Dynasty was that the distribution of settlements in this area changed from high altitudes to low ones and kept approaching the Chaohu Lake with the passage of time. These could be the response to the climate change from warm-moist to a relatively warm-dry condition during the middle Holocene, leading to the lake level fluctuations. The large area of exposed land provided enough space for human activities. These indicate that the above changes in geomorphologic evolution and hydrology influenced by climate condi- tions affected the transmutation of ancient settlements greatly. The distribution pattern of settlement sites was that the number of sites in the west was more than in the east. This pattern may be related to the geomorphologic conditions such as frequent channel shifting of the Yangtze River as well as flood disasters during the Holocene optimum. Therefore, climate change was the inducement of the transmutation of ancient settlements in the Chaohu Lake Basin, which exerted great influence on the distribution, expansion and development of the ancient settlements.展开更多
Background： Fat grafting technologies are popularly used in plastic and reconstructive surgery. Due to its size limitation, it is hard to directly inject untreated iht tissue into the dermal layer. Nanolht, which was...Background： Fat grafting technologies are popularly used in plastic and reconstructive surgery. Due to its size limitation, it is hard to directly inject untreated iht tissue into the dermal layer. Nanolht, which was introduced by Tonnard, solves this problem by mechanically emulsifying fat tissue. However, the viability of the cells was greatly destroyed. In this study, we reported a new method by ＂gently＂ digesting the fat tissue to produce viable adipocytes, progenitors, and stromal stem cells using collagenase I digestion and centrifugation. This was named ＂Vivo nanofat＂. Methods： Human liposuction aspirates were obtained from five healthy female donors with mean age of 28.7±5.6 years. Colony-forming assay, flow cytometry analysis, and adipogenic and osteogenic induction of the adherent cells from the Vivo nanofat were used to characterize the adipose mesenchymal stem cells （MSCs）. To investigate in vivo survival, we respectively injected Vivo nanofat and nanofat subcutaneously to the back of 8-week-old male BALB/c nude mice. Samples were harvested 2 days, 2 weeks, and 4 weeks postiniection for measurement, hematoxylin and eosin staining, and immunostaining. Results： Our results showed that the Vivo nanofat contained a large number ofcolony-fbrming cells. These cells expressed MSC markers and had multi-differentiative potential. In vivo transplantation showed that the Vivo nanofat had lower resorption ratio than that of nanofat. The size of the transplanted nanofat was obviously smaller than that of Vivo nanofat 4 weeks postinjection （0.50±0.17 cm vs. 0.81 ± 0.07 cm, t = -5783, P- 0.01）. Conclusion： Vivo nanofat may serve as a cell fraction injectable through a fine needle; this could be used for cosmetic applications.展开更多
Natural bone is a mineralized biological material, which serves a supportive and protective framework for the body, stores minerals for metabolism, and produces blood cells nourishing the body. Normally, bone has an i...Natural bone is a mineralized biological material, which serves a supportive and protective framework for the body, stores minerals for metabolism, and produces blood cells nourishing the body. Normally, bone has an innate capacity to heal from damage.However, massive bone defects due to traumatic injury, tumor resection, or congenital diseases pose a great challenge to reconstructive surgery. Scaffold-based tissue engineering(TE) is a promising strategy for bone regenerative medicine, because biomaterial scaffolds show advanced mechanical properties and a good degradation profile, as well as the feasibility of controlled release of growth and differentiation factors or immobilizing them on the material surface. Additionally, the defined structure of biomaterial scaffolds, as a kind of mechanical cue, can influence cell behaviors, modulate local microenvironment and control key features at the molecular and cellular levels. Recently, nano/micro-assisted regenerative medicine becomes a promising application of TE for the reconstruction of bone defects. For this reason, it is necessary for us to have in-depth knowledge of the development of novel nano/micro-based biomaterial scaffolds. Thus, we herein review the hierarchical structure of bone, and the potential application of nano/micro technologies to guide the design of novel biomaterial structures for bone repair and regeneration.展开更多
Dental Caries is a kind of chronic oral disease that greatly threaten human being’s health.Though dentists and researchers struggled for decades to combat this oral disease,the incidence and prevalence of dental cari...Dental Caries is a kind of chronic oral disease that greatly threaten human being’s health.Though dentists and researchers struggled for decades to combat this oral disease,the incidence and prevalence of dental caries remain quite high.Therefore,improving the disease management is a key issue for the whole population and life cycle management of dental caries.So clinical difficulty assessment system of caries prevention and management is established based on dental caries diagnosis and classification.Dentists should perform oral examination and establish dental records at each visit.When treatment plan is made on the base of caries risk assessment and carious lesion activity,we need to work out patient-centered and personalized treatment planning to regain oral microecological balance,to control caries progression and to restore the structure and function of the carious teeth.And the follow-up visits are made based on personalized caries management.This expert consensus mainly discusses caries risk assessment,caries treatment difficulty assessment and dental caries treatment plan,which are the most important parts of caries management in the whole life cycle.展开更多
With the applications of high technology,a catastrophic failure of CNC equipment rarely occurs at normal operation conditions.So it is difficult for traditional reliability assessment methods based on time-to-failure ...With the applications of high technology,a catastrophic failure of CNC equipment rarely occurs at normal operation conditions.So it is difficult for traditional reliability assessment methods based on time-to-failure distributions to deduce the reliability level.This paper presents a novel reliability assessment methodology to estimate the reliability level of equipment with machining performance degradation data when only a few samples are available.The least squares support vector machines(LS-SVM) are introduced to analyze the performance degradation process on the equipment.A two-stage parameter optimization and searching method is proposed to improve the LS-SVM regression performance and a reliability assessment model based on the LS-SVM is built.A machining performance degradation experiment has been carried out on an OTM650 machine tool to validate the effectiveness of the proposed reliability assessment methodology.展开更多
Background:This study aimed to develop a comprehensive instrument for evaluating and ranking clinical practice guidelines,named Scientific,Transparent and Applicable Rankings tool(STAR),and test its reliability,validi...Background:This study aimed to develop a comprehensive instrument for evaluating and ranking clinical practice guidelines,named Scientific,Transparent and Applicable Rankings tool(STAR),and test its reliability,validity,and usability.Methods:This study set up a multidisciplinary working group including guideline methodologists,statisticians,journal editors,clinicians,and other experts.Scoping review,Delphi methods,and hierarchical analysis were used to develop the STAR tool.We evaluated the instrument’s intrinsic and interrater reliability,content and criterion validity,and usability.Results:STAR contained 39 items grouped into 11 domains.The mean intrinsic reliability of the domains,indicated by Cronbach’sαcoefficient,was 0.588(95%confidence interval[CI]:0.414,0.762).Interrater reliability as assessed with Cohen’s kappa coefficient was 0.774(95%CI:0.740,0.807)for methodological evaluators and 0.618(95%CI:0.587,0.648)for clinical evaluators.The overall content validity index was 0.905.Pearson’s r correlation for criterion validity was 0.885(95%CI:0.804,0.932).The mean usability score of the items was 4.6 and the median time spent to evaluate each guideline was 20 min.Conclusion:The instrument performed well in terms of reliability,validity,and efficiency,and can be used for comprehensively evaluating and ranking guidelines.展开更多
The vegetation ecosystem of the Qinghai–Tibet Plateau in China,considered to be the′′natural laboratory′′of climate change in the world,has undergone profound changes under the stress of global change.Herein,we a...The vegetation ecosystem of the Qinghai–Tibet Plateau in China,considered to be the′′natural laboratory′′of climate change in the world,has undergone profound changes under the stress of global change.Herein,we analyzed and discussed the spatial-temporal change patterns and the driving mechanisms of net primary productivity(NPP)in the Qinghai–Tibet Plateau from 2000 to 2015 based on the gravity center and correlation coefficient models.Subsequently,we quantitatively distinguished the relative effects of climate change(such as precipitation,temperature and evapotranspiration)and human activities(such as grazing and ecological construction)on the NPP changes using scenario analysis and Miami model based on the MOD17A3 and meteorological data.The average annual NPP in the Qinghai–Tibet Plateau showed a decreasing trend from the southeast to the northwest during 2000–2015.With respect to the inter-annual changes,the average annual NPP exhibited a fluctuating upward trend from 2000 to 2015,with a steep increase observed in 2005 and a high fluctuation observed from 2005 to 2015.In the Qinghai–Tibet Plateau,the regions with the increase in NPP(change rate higher than 10%)were mainly concentrated in the Three-River Source Region,the northern Hengduan Mountains,the middle and lower reaches of the Yarlung Zangbo River,and the eastern parts of the North Tibet Plateau,whereas the regions with the decrease in NPP(change rate lower than–10%)were mainly concentrated in the upper reaches of the Yarlung Zangbo River and the Ali Plateau.The gravity center of NPP in the Qinghai–Tibet Plateau has moved southwestward during 2000–2015,indicating that the increment and growth rate of NPP in the southwestern part is greater than those of NPP in the northeastern part.Further,a significant correlation was observed between NPP and climate factors in the Qinghai–Tibet Plateau.The regions exhibiting a significant correlation between NPP and precipitation were mainly located in the central and eastern Qinghai–Tibet展开更多
基金partially supported by the National Key Research and Development Program of China(2016YFA0600104)supported by donations made by Delos Living LLC,and the Cyrus Tang Foundation+2 种基金supported by the National Natural Science Foundation of China(41471419)Beijing Institute of Urban Planningsupported by the Fundamental Research Funds for the Central Universities(CCNU19TD002).
文摘Land use reflects human activities on land.Urban land use is the highest level human alteration on Earth,and it is rapidly changing due to population increase and urbanization.Urban areas have widespread effects on local hydrology,climate,biodiversity,and food production[1,2].However,maps,that contain knowledge on the distribution,pattern and composition of various land use types in urban areas,are limited to city level.The mapping standard on data sources,methods,land use classification schemes varies from city to city,due to differences in financial input and skills of mapping personnel.To address various national and global environmental challenges caused by urbanization,it is important to have urban land uses at the national and global scales that are derived from the same or consistent data sources with the same or compatible classification systems and mapping methods.This is because,only with urban land use maps produced with similar criteria,consistent environmental policies can be made,and action efforts can be compared and assessed for large scale environmental administration.However,despite of the fact that a number of urban-extent maps exist at global scales[3,4],more detailed urban land use maps do not exist at the same scale.Even at big country or regional levels such as for the United States,China and European Union,consistent land use mapping efforts are rare[5,6](e.g.,https://sdi4apps.eu/open_land_use/).
基金The work of A.Jacobsen,C.Evelo,M.Thompson,R.Cornet,R.Kaliyaperuma and M.Roos is supported by funding from the European Union’s Horizon 2020 research and innovation program under the EJP RD COFUND-EJP N°825575.The work of A.Jacobsen,C.Evelo,C.Goble,M.Thompson,N.Juty,R.Hooft,M.Roos,S-A.Sansone,P.McQuilton,P.Rocca-Serra and D.Batista is supported by funding from ELIXIR EXCELERATE,H2020 grant agreement number 676559.R.Hooft was further funded by NL NWO NRGWI.obrug.2018.009.N.Juty and C.Goble were funded by CORBEL(H2020 grant agreement 654248)N.Juty,C.Goble,S-A.Sansone,P.McQuilton,P.Rocca-Serra and D.Batista were funded by FAIRplus(IMI grant agreement 802750)+12 种基金N.Juty,C.Goble,M.Thompson,M.Roos,S-A.Sansone,P.McQuilton,P.Rocca-Serra and D.Batista were funded by EOSClife H2020-EU(grant agreement number 824087)C.Goble was funded by DMMCore(BBSRC BB/M013189/)M.Thompson,M.Roos received funding from NWO(VWData 400.17.605)S-A.Sansone,P.McQuilton,P.Rocca-Serra and D.Batista have been funded by grants awarded to S-A.Sansone from the UK BBSRC and Research Councils(BB/L024101/1,BB/L005069/1)EU(H2020-EU 634107H2020-EU 654241,IMI(IMPRiND 116060)NIH Data Common Fund,and from the Wellcome Trust(ISA-InterMine 212930/Z/18/ZFAIRsharing 208381/A/17/Z)The work of A.Waagmeester has been funded by grant award number GM089820 from the National Institutes of Health.M.Kersloot was funded by the European Regional Development Fund(KVW-00163).The work of N.Meyers was funded by the National Science Foundation(OAC 1839030)The work of M.D.Wilkinson is funded by Isaac Peral/Marie Curie cofund with the Universidad Politecnica de Madrid and the Ministerio de Economia y Competitividad grant number TIN2014-55993-RMThe work of B.Magagna,E.Schultes,L.da Silva Santos and K.Jeffery is funded by the H2020-EU 824068The work of B.Magagna,E.Schultes and L.da Silva Santos is funded by the GO FAIR ISCO grant of the Dutch Ministry of Science and CultureThe work of G.Guizzardi is supported by the OCEAN Project(FUB).M.Courtot received funding from the I
文摘The FAIR principles have been widely cited,endorsed and adopted by a broad range of stakeholders since their publication in 2016.By intention,the 15 FAIR guiding principles do not dictate specific technological implementations,but provide guidance for improving Findability,Accessibility,Interoperability and Reusability of digital resources.This has likely contributed to the broad adoption of the FAIR principles,because individual stakeholder communities can implement their own FAIR solutions.However,it has also resulted in inconsistent interpretations that carry the risk of leading to incompatible implementations.Thus,while the FAIR principles are formulated on a high level and may be interpreted and implemented in different ways,for true interoperability we need to support convergence in implementation choices that are widely accessible and(re)-usable.We introduce the concept of FAIR implementation considerations to assist accelerated global participation and convergence towards accessible,robust,widespread and consistent FAIR implementations.Any self-identified stakeholder community may either choose to reuse solutions from existing implementations,or when they spot a gap,accept the challenge to create the needed solution,which,ideally,can be used again by other communities in the future.Here,we provide interpretations and implementation considerations(choices and challenges)for each FAIR principle.
基金supported by the National Key Basic Research Program on Global Change of China(2011CB952001)the National Key Basic Research Special Foundation of China(2006FY1106000)the Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)and the Open Fund Program of the State Key Laboratory of RemoteSensing Science,China(OFSLRSS201112)
文摘During the years 2006–2009,lakes in the Qinghai-Tibetan Plateau(QTP)were investigated using satellite remote sensing strategies.We report the results of this investigation as well as follow-up research and expanded work.For the investigation,we mainly focused on lakes whose areas are more than 1 km2.The remote sensing data that we used included 408 scenes of CBERS CCD images and 5 scenes of Landsat ETM?images in Qinghai Province and Tibet Autonomous Region.All these data were acquired around years 2005–2006.Besides remote sensing images,we also collected 1,259 topographic maps.Numbers and areas of lakes were analyzed statistically,which were then compared with those coming from the first lake investigation(implemented between the1960s and 1980s).According to our investigation,up to and around year 2005–2006,the total number of lakes in the QTP was 1,055(222 in Qinghai and 833 in Tibet),accounting for more than 30%of that of China.Thirty newborn lakes with area[1 km2were found,and 5 dead lakes with initial area[1 km2were also found.Among those 13 big lakes([500 km2),Yamzhog Yumco had seriously shrunk,and it has continued to shrink in recent years;Qinghai Lake had shrunk during the period,but some new researches indicated that it has been expanding since the year 2004;Siling Co,Nam Co,and Chibuzhang Co had expanded in the period.We divided the newborn lakes into six categories according to their forming reasons,including river expansion,wetland conversion,etc.The changes of natural conditions led to the death of four lakes,and human exploitation was the main reason for the death of Dalianhai Lake in Qinghai.We picked out three regions which were sensitive to the change of climate and ecological environment:Nagqu Region,Kekexili Region,and the source area of the Yellow River(SAYR).Lakes in both Nagqu and Kekexili have been expanded;meanwhile,most lakes in the SAYR have obviously been shrunk.These regional patterns of lake changes were highly related to variations of temperature,glacier,precipitation,and evapor
基金supported by National Natural Science Foundation of China(Grant Nos. 40930530 and 40901180)
文摘Highly accurate observations at various scales on the land surface are urgently needed for the studies of many areas,such as hydrology,meteorology,and agriculture.With the rapid development of remote sensing techniques,remote sensing has had the capacity of monitoring many factors of the Earth's land surface.Especially,the space-borne microwave remote sensing systems have been widely used in the quantitative monitoring of global snow,soil moisture,and vegetation parameters with their all-weather,all-time observation capabilities and their sensitivities to the characteristics of land surface factors.Based on the electromagnetic theories and microwave radiative transfer equations,researchers have achieved great successes in the microwave remote sensing studies for different sensors in recent years.This article has systematically reviewed the progresses on five research areas including microwave theoretical modeling,microwave inversion on soil moisture,snow,vegetation and land surface temperatures.Through the further enrichment of remote sensing datasets and the development of remote sensing theories and inversion techniques,remote sensing including microwave remote sensing will play a more important role in the studies and applications of the Earth systems.
基金supported by the National Key Research and Development Program of China(Grant Nos.2021YFC2203501,2021YFC2203502,2021YFC2203503,and 2021YFC2203600)the National Natural Science Foundation of China(Grant Nos.12173077,11873082,11803080,and 12003062)+3 种基金the Scientific Instrument Developing Project of the Chinese Academy of Sciences(Grant No.PTYQ2022YZZD01)the Operation,Maintenance and Upgrading Fund for Astronomical Telescopes and Facility Instrumentsbudgeted from the Ministry of Finance of China and Administrated by the Chinese Academy of Sciencesthe Chinese Academy of Sciences“Light of West China”Program(Grant No.2021-XBQNXZ-030)。
文摘This study presents a general outline of the Qitai radio telescope(QTT)project.Qitai,the site of the telescope,is a county of Xinjiang Uygur Autonomous Region of China,located in the east Tianshan Mountains at an elevation of about 1800 m.The QTT is a fully steerable,Gregorian-type telescope with a standard parabolic main reflector of 110 m diameter.The QTT has adopted an umbrella support,homology-symmetric lightweight design.The main reflector is active so that the deformation caused by gravity can be corrected.The structural design aims to ultimately allow high-sensitivity observations from 150 MHz up to115 GHz.To satisfy the requirements for early scientific goals,the QTTwill be equipped with ultra-wideband receivers and large field-of-view multi-beam receivers.A multi-function signal-processing system based on RFSo C and GPU processor chips will be developed.These will enable the QTT to operate in pulsar,spectral line,continuum and Very Long Baseline Interferometer(VLBI)observing modes.Electromagnetic compatibility(EMC)and radio frequency interference(RFI)control techniques are adopted throughout the system design.The QTT will form a world-class observational platform for the detection of lowfrequency(nano Hertz)gravitational waves through pulsar timing array(PTA)techniques,pulsar surveys,the discovery of binary black-hole systems,and exploring dark matter and the origin of life in the universe.The QTT will also play an important role in improving the Chinese and international VLBI networks,allowing high-sensitivity and high-resolution observations of the nuclei of distant galaxies and gravitational lensing systems.Deep astrometric observations will also contribute to improving the accuracy of the celestial reference frame.Potentially,the QTT will be able to support future space activities such as planetary exploration in the solar system and to contribute to the search for extraterrestrial intelligence.
基金the Twelfth Five-Year National Key Technologies Research and Development Program of China(grant no.2012BAI07B00)the National High Technology Research and Development Program(‘863’Program)of China(grant nos.2013AA040801 and 2013AA040802)+1 种基金the National Natural Science Foundation of China(grant no.81271181)the Scientific Research Innovation Foundation for Youth Doctors of Peking University School of Stomatology(2011)
文摘The article introduces a new method for three-dimensional reproduction of edentulous dental casts,and wax occlusion rims with jaw relation by using a commercial high-speed line laser scanner and reverse engineering software and evaluates the method’s accuracy in vitro.The method comprises three main steps：（i）acquisition of the three-dimensional stereolithography data of maxillary and mandibular edentulous dental casts and wax occlusion rims;（ii）acquisition of the three-dimensional stereolithography data of jaw relations;and（iii）registration of these data with the reverse engineering software and completing reconstruction.To evaluate the accuracy of this method,dental casts and wax occlusion rims of 10 edentulous patients were used.The lengths of eight lines between common anatomic landmarks were measured directly on the casts and occlusion rims by using a vernier caliper and on the three-dimensional computerized images by using the software measurement tool.The direct data were considered as the true values.The paired-samples t-test was used for statistical analysis.The mean differences between the direct and the computerized measurements were mostly less than 0.04 mm and were not significant（P.0.05）.Statistical significance among 10 patients was assessed using one-way analysis of variance（P,0.05）.The result showed that the 10 patients were considered statistically no significant.Therefore,accurate three-dimensional reproduction of the edentulous dental casts,wax occlusion rims,and jaw relations was achieved.The proposed method enables the visualization of occlusion from different views and would help to meet the demand for the computer-aided design of removable complete dentures.
基金funded by“The Pearl River Talent Recruitment Program”in 2019(Grant No.2019CX01G338),。
文摘This paper introduces an intelligent framework for predicting the advancing speed during earth pressure balance(EPB)shield tunnelling.Five artificial intelligence(AI)models based on machine and deep learning techniques-back-propagation neural network(BPNN),extreme learning machine(ELM),support vector machine(SVM),long-short term memory(LSTM),and gated recurrent unit(GRU)-are used.Five geological and nine operational parameters that influence the advancing speed are considered.A field case of shield tunnelling in Shenzhen City,China is analyzed using the developed models.A total of 1000 field datasets are adopted to establish intelligent models.The prediction performance of the five models is ranked as GRU>LSTM>SVM>ELM>BPNN.Moreover,the Pearson correlation coefficient(PCC)is adopted for sensitivity analysis.The results reveal that the main thrust(MT),penetration(P),foam volume(FV),and grouting volume(GV)have strong correlations with advancing speed(AS).An empirical formula is constructed based on the high-correlation influential factors and their corresponding field datasets.Finally,the prediction performances of the intelligent models and the empirical method are compared.The results reveal that all the intelligent models perform better than the empirical method.
基金This work was supported,in part,by the National Nature Science Foundation of China under Grant Numbers 61502240,61502096,61304205,61773219in part,by the Natural Science Foundation of Jiangsu Province under grant numbers BK20201136,BK20191401+1 种基金in part,by the Postgraduate Research&Practice Innovation Program of Jiangsu Province under Grant Numbers SJCX21_0363in part,by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)fund.
文摘Vehicle re-identification(ReID)aims to retrieve the target vehicle in an extensive image gallery through its appearances from various views in the cross-camera scenario.It has gradually become a core technology of intelligent transportation system.Most existing vehicle re-identification models adopt the joint learning of global and local features.However,they directly use the extracted global features,resulting in insufficient feature expression.Moreover,local features are primarily obtained through advanced annotation and complex attention mechanisms,which require additional costs.To solve this issue,a multi-feature learning model with enhanced local attention for vehicle re-identification(MFELA)is proposed in this paper.The model consists of global and local branches.The global branch utilizes both middle and highlevel semantic features of ResNet50 to enhance the global representation capability.In addition,multi-scale pooling operations are used to obtain multiscale information.While the local branch utilizes the proposed Region Batch Dropblock(RBD),which encourages the model to learn discriminative features for different local regions and simultaneously drops corresponding same areas randomly in a batch during training to enhance the attention to local regions.Then features from both branches are combined to provide a more comprehensive and distinctive feature representation.Extensive experiments on VeRi-776 and VehicleID datasets prove that our method has excellent performance.
基金This work was supported by the National Key R&D Program of China(2018YFC1105303/04)National Natural Science Foundation of China(Nos.51772006,31670993,51973004,81991505,82022016)+3 种基金Beijing Municipal Science&Technology Commission Projects(Z181100002018001)Peking University Medicine Fund(Nos.PKU2020LCXQ009,BMU2020PYB029)Natural Science Foundation of Hunan Province(2019JJ50779)Health and Family Planning Commission of Hunan Province(20180246).
文摘Macrophage-mediated inflammation compromises bone repair in diabetic patients.Electrical signaling cues are known to regulate macrophage functions.However,the biological effects of electrical microenvironment from charged biomaterials on the immune response for regulating osteogenesis under diabetic conditions remain to be elucidated.Herein the endogeneous electrical microenvironment of native bone tissue was recapitulated by fabricating a ferroelectric BaTiO_(3)/poly(vinylidene fluoridetrifluoroethylene)(BTO/P(VDF-TrFE))nanocomposite membrane.In vitro,the polarized BaTiO_(3)/poly(vinylidene fluoridetrifluoroethylene)(BTO/P(VDF-TrFE))nanocomposite membranes inhibited high glucose-induced M1-type inflammation,by effecting changes in cell morphology,M1 marker expression and pro-inflammatory cytokine secretion in macrophages.This led to enhanced osteogenic differentiation of human bone marrow mesenchymal stem cells(BM-MSCs).In vivo,the biomimetic electrical microenvironment recapitulated by the polarized nanocomposite membranes switched macrophage phenotype from the pro-inflammatory(M1)into the pro-healing(M2)phenotype,which in turn enhanced bone regeneration in rats with type 2 diabetes mellitus.Mechanistic studies revealed that the biomimetic electrical microenvironment attenuated pro-inflammatory M1 macrophage polarization under hyperglycemic conditions by suppressing expression of AKT2 and IRF5 within the PI3K-AKT signaling pathway,thereby inducing favorable osteo-immunomodulatory effects.Our study thus provides fundamental insights into the biological effects of restoring the electrical microenvironment conducive for osteogenesis under DM conditions,and offers an effective strategy to design functionalized biomaterials for bone regeneration therapy in diabetic patients.
基金supported by National Science Fund for Distinguished Young Scholars of China(No.51625502)Innovative Group Project of National Natural Science Foundation of China(No.51721092)Innovative Group Project of Hubei Province of China(No.2017CFA003)。
文摘Due to the advantages of large workspace,low cost and the integrated vision/force sensing,robotic milling has become an important way for machining of complex parts.In recent years,many scholars have studied the problems existing in the applications of robotic milling,and lots of results have been made in the dynamics,pose planning,deformation control etc.,which provides theoretical guidance for high precision and high efficiency of robotic milling.From the perspective of complex parts robotic milling,this paper focuses on machining process planning and control techniques including the analysis of the robot-workspace,robot trajectory planning,vibration monitoring and control,deformation monitoring and compensation.As well as the principles of these technologies such as robot stiffness characteristics,dynamic characteristics,chatter mechanisms,and deformation mechanisms.The methods and characteristics related to the theory and technology of robotic milling of complex parts are summarized systematically.The latest research progress and achievements in the relevant fields are reviewed.It is hoped that the challenges,strategies and development related to robotic milling could be clarified through the carding work in this paper,so as to promote the application of related theories and technologies in high efficiency and precision intelligent milling with robot for complex parts.
基金Under the auspices of Major Program of the National Natural Science Foundation of China ‘Coupled mechanisms and interactive coercing effects between urbanization and eco-environment in mega-urban agglomerations’(No.41590842)
文摘Urban agglomerations are spatial entities that promote the development of ‘new urbanization' processes within China. In this context, the concept of ‘multiscale urban agglomeration spaces' encompasses three linked levels: macroscale urban agglomerations, mesoscale cities, and microscale urban centers. Applying a series of multidisciplinary integrated research methods drawn from geography, urban planning, and architecture, this paper reveals two intensive utilization laws that can be generalized to apply to multiscale urban agglomeration spaces, top-to-bottom ‘positive transmission' linkage and inside-to-outside ‘negative transmission' movement. This paper also proposes optimization transmission theory and policy decision technical pathways that can be applied to these three urban agglomeration spatial scales. Specific technical pathways of transmission include intensive expansion and simulated decision-making in macroscale urban agglomerations, ecology, production, and living space intensive layout and dynamic decision-making in mesoscale cities, and four cores(i.e., ‘single, ring, axis, and pole core') progressive linkage and intensive optimization decision-making in microscale urban centers. The theory and technical pathways proposed in this paper solve the technical problem of optimization and provide intensive methods that can be applied not only at the individual level but also at multiple scales in urban agglomeration spaces. This study also advances a series of comprehensive technical solutions that can be applied to both compact and smart growth cities as well as to urban agglomerations. Solid theoretical support is provided for the optimization of Chinese land development, urbanization, agricultural development, and ecological security.
基金Major Program of Natural Science Research at University of Anhui Province, No.ZD200908 National Sci ence and Technology Support Program, No.2010BAK67B02+1 种基金 National Natural Science Foundation of China, No.41010104005 No.40971115This work is supported by the Tracing Origin Project of Chinese Civilization. We thank Dr. An Ran and Dr. Heim. Jordan in Purdue University, USA, for their kind help and valuable discussions.
文摘Based on the temporal-spatial distribution features of ancient settlement sites from the middle and late Neolithic Age to the Han dynasty in the Chaohu Lake Basin of Anhui Province, East China, using the methods of GIS combined with the reconstructed paleoen- vironment by the records of lake sediment since Holocene, the transmutation of ancient set- tlements with response to environmental changes in this area has been discussed. Studies show that the main feature of transmutation of ancient settlements from the middle and late Neolithic Age to the Han Dynasty was that the distribution of settlements in this area changed from high altitudes to low ones and kept approaching the Chaohu Lake with the passage of time. These could be the response to the climate change from warm-moist to a relatively warm-dry condition during the middle Holocene, leading to the lake level fluctuations. The large area of exposed land provided enough space for human activities. These indicate that the above changes in geomorphologic evolution and hydrology influenced by climate condi- tions affected the transmutation of ancient settlements greatly. The distribution pattern of settlement sites was that the number of sites in the west was more than in the east. This pattern may be related to the geomorphologic conditions such as frequent channel shifting of the Yangtze River as well as flood disasters during the Holocene optimum. Therefore, climate change was the inducement of the transmutation of ancient settlements in the Chaohu Lake Basin, which exerted great influence on the distribution, expansion and development of the ancient settlements.
文摘Background： Fat grafting technologies are popularly used in plastic and reconstructive surgery. Due to its size limitation, it is hard to directly inject untreated iht tissue into the dermal layer. Nanolht, which was introduced by Tonnard, solves this problem by mechanically emulsifying fat tissue. However, the viability of the cells was greatly destroyed. In this study, we reported a new method by ＂gently＂ digesting the fat tissue to produce viable adipocytes, progenitors, and stromal stem cells using collagenase I digestion and centrifugation. This was named ＂Vivo nanofat＂. Methods： Human liposuction aspirates were obtained from five healthy female donors with mean age of 28.7±5.6 years. Colony-forming assay, flow cytometry analysis, and adipogenic and osteogenic induction of the adherent cells from the Vivo nanofat were used to characterize the adipose mesenchymal stem cells （MSCs）. To investigate in vivo survival, we respectively injected Vivo nanofat and nanofat subcutaneously to the back of 8-week-old male BALB/c nude mice. Samples were harvested 2 days, 2 weeks, and 4 weeks postiniection for measurement, hematoxylin and eosin staining, and immunostaining. Results： Our results showed that the Vivo nanofat contained a large number ofcolony-fbrming cells. These cells expressed MSC markers and had multi-differentiative potential. In vivo transplantation showed that the Vivo nanofat had lower resorption ratio than that of nanofat. The size of the transplanted nanofat was obviously smaller than that of Vivo nanofat 4 weeks postinjection （0.50±0.17 cm vs. 0.81 ± 0.07 cm, t = -5783, P- 0.01）. Conclusion： Vivo nanofat may serve as a cell fraction injectable through a fine needle; this could be used for cosmetic applications.
基金The authors acknowledge the financial support from the Beijing Municipal Natural Science Foundation No.2184119(D.L.)and No.L182005(Y.L.)the Projects of Beijing Nova Programme No.Z171100001117018(Y.L.)+2 种基金Beijing Nova Programme Interdisciplinary Cooperation Project No.Z181100006218135(Y.L.and D.L.)the National Natural Science Foundations of China No.81571815(Y.L.),No.81871492(Y.L.)and No.51902344(D.L.)the Science Foundation of China University of Petroleum No.2462018BJB002(D.L.).
文摘Natural bone is a mineralized biological material, which serves a supportive and protective framework for the body, stores minerals for metabolism, and produces blood cells nourishing the body. Normally, bone has an innate capacity to heal from damage.However, massive bone defects due to traumatic injury, tumor resection, or congenital diseases pose a great challenge to reconstructive surgery. Scaffold-based tissue engineering(TE) is a promising strategy for bone regenerative medicine, because biomaterial scaffolds show advanced mechanical properties and a good degradation profile, as well as the feasibility of controlled release of growth and differentiation factors or immobilizing them on the material surface. Additionally, the defined structure of biomaterial scaffolds, as a kind of mechanical cue, can influence cell behaviors, modulate local microenvironment and control key features at the molecular and cellular levels. Recently, nano/micro-assisted regenerative medicine becomes a promising application of TE for the reconstruction of bone defects. For this reason, it is necessary for us to have in-depth knowledge of the development of novel nano/micro-based biomaterial scaffolds. Thus, we herein review the hierarchical structure of bone, and the potential application of nano/micro technologies to guide the design of novel biomaterial structures for bone repair and regeneration.
基金supported by National Natural Science Foundation of China[81870759]。
文摘Dental Caries is a kind of chronic oral disease that greatly threaten human being’s health.Though dentists and researchers struggled for decades to combat this oral disease,the incidence and prevalence of dental caries remain quite high.Therefore,improving the disease management is a key issue for the whole population and life cycle management of dental caries.So clinical difficulty assessment system of caries prevention and management is established based on dental caries diagnosis and classification.Dentists should perform oral examination and establish dental records at each visit.When treatment plan is made on the base of caries risk assessment and carious lesion activity,we need to work out patient-centered and personalized treatment planning to regain oral microecological balance,to control caries progression and to restore the structure and function of the carious teeth.And the follow-up visits are made based on personalized caries management.This expert consensus mainly discusses caries risk assessment,caries treatment difficulty assessment and dental caries treatment plan,which are the most important parts of caries management in the whole life cycle.
文摘With the applications of high technology,a catastrophic failure of CNC equipment rarely occurs at normal operation conditions.So it is difficult for traditional reliability assessment methods based on time-to-failure distributions to deduce the reliability level.This paper presents a novel reliability assessment methodology to estimate the reliability level of equipment with machining performance degradation data when only a few samples are available.The least squares support vector machines(LS-SVM) are introduced to analyze the performance degradation process on the equipment.A two-stage parameter optimization and searching method is proposed to improve the LS-SVM regression performance and a reliability assessment model based on the LS-SVM is built.A machining performance degradation experiment has been carried out on an OTM650 machine tool to validate the effectiveness of the proposed reliability assessment methodology.
基金funded by China Scholarship Council(Grant No.202206180007)funded by China Scholarship Council(Grant No.202206180006).
文摘Background:This study aimed to develop a comprehensive instrument for evaluating and ranking clinical practice guidelines,named Scientific,Transparent and Applicable Rankings tool(STAR),and test its reliability,validity,and usability.Methods:This study set up a multidisciplinary working group including guideline methodologists,statisticians,journal editors,clinicians,and other experts.Scoping review,Delphi methods,and hierarchical analysis were used to develop the STAR tool.We evaluated the instrument’s intrinsic and interrater reliability,content and criterion validity,and usability.Results:STAR contained 39 items grouped into 11 domains.The mean intrinsic reliability of the domains,indicated by Cronbach’sαcoefficient,was 0.588(95%confidence interval[CI]:0.414,0.762).Interrater reliability as assessed with Cohen’s kappa coefficient was 0.774(95%CI:0.740,0.807)for methodological evaluators and 0.618(95%CI:0.587,0.648)for clinical evaluators.The overall content validity index was 0.905.Pearson’s r correlation for criterion validity was 0.885(95%CI:0.804,0.932).The mean usability score of the items was 4.6 and the median time spent to evaluate each guideline was 20 min.Conclusion:The instrument performed well in terms of reliability,validity,and efficiency,and can be used for comprehensively evaluating and ranking guidelines.
基金supported by the Natural Science Foundation of Shandong Province(ZR2018BD001)the Project of Shandong Province Higher Educational Science and Technology Program(J18KA181)+4 种基金the Key Research Program of Frontier Science of Chinese Academy of Sciences(QYZDY-SSW-DQC007)the Open Fund of Key Laboratory of Geographic Information Science(Ministry of Education),East China Normal University(KLGIS2017A02)the Open Fund of State Laboratory of Information Engineering in Surveying,Mapping and Remote Sensing,Wuhan University(17I04)the Open Fund of Key Laboratory of Geomatics and Digital Technology of Shandong Provincethe National Key R&D Program of China(2017YFA0604804)
文摘The vegetation ecosystem of the Qinghai–Tibet Plateau in China,considered to be the′′natural laboratory′′of climate change in the world,has undergone profound changes under the stress of global change.Herein,we analyzed and discussed the spatial-temporal change patterns and the driving mechanisms of net primary productivity(NPP)in the Qinghai–Tibet Plateau from 2000 to 2015 based on the gravity center and correlation coefficient models.Subsequently,we quantitatively distinguished the relative effects of climate change(such as precipitation,temperature and evapotranspiration)and human activities(such as grazing and ecological construction)on the NPP changes using scenario analysis and Miami model based on the MOD17A3 and meteorological data.The average annual NPP in the Qinghai–Tibet Plateau showed a decreasing trend from the southeast to the northwest during 2000–2015.With respect to the inter-annual changes,the average annual NPP exhibited a fluctuating upward trend from 2000 to 2015,with a steep increase observed in 2005 and a high fluctuation observed from 2005 to 2015.In the Qinghai–Tibet Plateau,the regions with the increase in NPP(change rate higher than 10%)were mainly concentrated in the Three-River Source Region,the northern Hengduan Mountains,the middle and lower reaches of the Yarlung Zangbo River,and the eastern parts of the North Tibet Plateau,whereas the regions with the decrease in NPP(change rate lower than–10%)were mainly concentrated in the upper reaches of the Yarlung Zangbo River and the Ali Plateau.The gravity center of NPP in the Qinghai–Tibet Plateau has moved southwestward during 2000–2015,indicating that the increment and growth rate of NPP in the southwestern part is greater than those of NPP in the northeastern part.Further,a significant correlation was observed between NPP and climate factors in the Qinghai–Tibet Plateau.The regions exhibiting a significant correlation between NPP and precipitation were mainly located in the central and eastern Qinghai–Tibet
