Background:Large Language Models(LLMs)have gained much attention and,in part,have replaced common search engines as a popular channel for obtaining information due to their contextually relevant responses.Osteoarthrit...Background:Large Language Models(LLMs)have gained much attention and,in part,have replaced common search engines as a popular channel for obtaining information due to their contextually relevant responses.Osteoarthritis(OA)is a common topic in skeletal muscle disor-ders,and patients often seek information about it online.Our study evaluated the ability of 3 LLMs(ChatGPT-3.5,ChatGPT-4.0,and Perplexity)to accurately answer common OA-related queries.Methods:We defined 6 themes(pathogenesis,risk factors,clinical presentation,diagnosis,treatment and prevention,and prognosis)based on a generalization of 25 frequently asked questions about OA.Three consultant-level orthopedic specialists independently rated the LLMs’replies on a 4-point accuracy scale.Thefinal ratings for each response were determined using a majority consensus approach.Responses classified as“satisfactory”were evaluated for comprehensiveness on a 5-point scale.Results:ChatGPT-4.0 demonstrated superior accuracy,with 64%of responses rated as“excellent”,compared to 40%for ChatGPT-3.5 and 28%for Perplexity(Pearson’s x2 test with Fisher’s exact test,all p<0.001).All 3 LLM-chatbots had high mean comprehensiveness ratings(Perplexity=3.88;ChatGPT-4.0=4.56;ChatGPT-3.5=3.96,out of a maximum score of 5).The LLM-chatbots performed reliably across domains,except for“treatment and prevention”However,ChatGPT-4.0 still outperformed ChatGPT-3.5 and Perplexity,garnering 53.8%“excellent”ratings(Pearson’s x2 test with Fisher’s exact test,all p<0.001).Conclusion:Ourfindings underscore the potential of LLMs,specifically ChatGPT-4.0 and Perplexity,to deliver accurate and thorough responses to OA-related queries.Targeted correction of specific misconceptions to improve the accuracy of LLMs remains crucial.展开更多
Models disagree on a significant number of responses to climate change,such as climate feedback,regional changes,or the strength of equilibrium climate sensitivity.Emergent constraints aim to reduce these uncertaintie...Models disagree on a significant number of responses to climate change,such as climate feedback,regional changes,or the strength of equilibrium climate sensitivity.Emergent constraints aim to reduce these uncertainties by finding links between the inter-model spread in an observable predictor and climate projections.In this paper,the concepts underlying this framework are recalled with an emphasis on the statistical inference used for narrowing uncertainties,and a review of emergent constraints found in the last two decades.Potential links between highlighted predictors are explored,especially those targeting uncertainty reductions in climate sensitivity,cloud feedback,and changes of the hydrological cycle.Yet the disagreement across emergent constraints suggests that the spread in climate sensitivity can not be significantly narrowed.This calls for weighting the realism of emergent constraints by quantifying the level of physical understanding explaining the relationship.This would also permit more efficient model evaluation and better targeted model development.In the context of the upcoming CMIP6 model intercomparison a growing number of new predictors and uncertainty reductions is expected,which call for robust statistical inferences that allow cross-validation of more likely estimates.展开更多
The aerosol optical properties and direct radiative forcing over the Mu Us desert of northern China, acquired through a CE318 sunphotometer of the ground-based Aerosol Robotic Network （AERONET）, are analyzed. The se...The aerosol optical properties and direct radiative forcing over the Mu Us desert of northern China, acquired through a CE318 sunphotometer of the ground-based Aerosol Robotic Network （AERONET）, are analyzed. The seasonal variations in the aerosol optical properties are examined. The effect of meteorological elements （pressure, temperature, water vapor pressure, relative humidity and wind speed） on the aerosol optical properties is also studied. Then, the sources and optical properties under two different cases, a dust event and a pollution event, are compared. The results show that the high aerosol optical depth （AOD） found in Yulin was mostly attributed to the occurrence of dust events in spring from the Mu Us desert and deserts of West China and Mongolia, as well as the impacts of anthropogenic pollutant particles from the middle part of China in the other seasons. The seasonal variation and the probability distribution of the radiative forcing and the radiative forcing efficiency at the surface and the top of the atmosphere are analyzed and regressed using the linear and Gaussian regression methods.展开更多
This study demonstrated the usefulness of very long-range terrestrial laser scanning(TLS) for analysis of the spatial distribution of a snowpack, to distances up to 3000 m, one of the longest measurement range reporte...This study demonstrated the usefulness of very long-range terrestrial laser scanning(TLS) for analysis of the spatial distribution of a snowpack, to distances up to 3000 m, one of the longest measurement range reported to date. Snow depth data were collected using a terrestrial laser scanner during 11 periods of snow accumulation and melting,over three snow seasons on a Pyrenean hillslopecharacterized by a large elevational gradient, steep slopes, and avalanche occurrence. The maximum and mean absolute snow depth error found was 0.5-0.6 and 0.2-0.3 m respectively, which may result problematic for areas with a shallow snowpack, but it is sufficiently accurate to determine snow distribution patterns in areas characterized by a thick snowpack. The results indicated that in most cases there was temporal consistency in the spatial distribution of thesnowpack, even in different years. The spatial patterns were particularly similar amongst thesurveys conducted during the period dominated by snow accumulation(generally until end of April), or amongst those conducted during the period dominated by melting processes(generally after mid of April or early May). Simple linear correlation analyses for the 11 survey dates, and the application of Random Forests analysis to two days representative of snow accumulation and melting periods indicated the importance of topography to the snow distribution. The results also highlight that elevation and the Topographic Position index(TPI) were the main variables explaining the snow distribution, especially during periods dominated by melting. The intra-and inter-annual spatial consistency of the snowpack distribution suggests that the geomorphological processes linked to presence/absence of snow cover act in a similar way in the long term, and that these spatial patternscan be easily identifiedthrough several years of adequate monitoring.展开更多
A relationship between oceanic conditions in the northwestern equatorial Atlantic (NWEA) and the seasonal rainfall over the northern part of Brazilian Northeast (NNEB) allows large climate events to be forecasted with...A relationship between oceanic conditions in the northwestern equatorial Atlantic (NWEA) and the seasonal rainfall over the northern part of Brazilian Northeast (NNEB) allows large climate events to be forecasted with a delay of a few months. Observed sea surface variables (sea surface temperature, wind stress and latent heat flux) and reanalyzed temperature and salinity profiles at depths of 0 - 150 m are used during 1974-2008. Perturbations in the Wind-Evaporation-SST mechanism over the NWEA during the last months of the year and the first months of the following year are of primary importance in evaluating the risk that strong climate events will affect the subsequent seasonal rainfall (in March-April) over the NNEB. Especially interesting are the Barrier Layer Thickness (BLT) and Ocean Heat Content (OHC) in the NWEA region from August-September through the subsequent months, during which a slow and steady evolution is apparent, with the highest signal occurring in October-November. Through their relationship with the local surface dynamic conditions, such BLT and OHC perturbations during the last months of the year can be used as a valuable indicator for forecasting wet or dry events over the NNEB during the subsequent rainfall season. A proposal is discussed to deploy additional temperature/conductivity sensors down to a depth of 140 m at three PIRATA moorings located in the NWEA region. That will be necessary if the BLT and other parameters of energy exchange between the ocean and atmosphere are to be estimated in real time and with a sufficiently high vertical resolution.展开更多
Mechanical loading is required for bone homeostasis,but the underlying mechanism is still unclear.Our previous studies revealed that the mechanical protein polycystin-1(PC1,encoded by Pkd1)is critical for bone formati...Mechanical loading is required for bone homeostasis,but the underlying mechanism is still unclear.Our previous studies revealed that the mechanical protein polycystin-1(PC1,encoded by Pkd1)is critical for bone formation.However,the role of PC1 in bone resorption is unknown.Here,we found that PC1directly regulates osteoclastogenesis and bone resorption.The conditional deletion of Pkd1 in the osteoclast lineage resulted in a reduced number of osteoclasts,decreased bone resorption,and increased bone mass.A cohort study of 32,500 patients further revealed that autosomal dominant polycystic kidney disease,which is mainly caused by loss-of-function mutation of the PKD1 gene,is associated with a lower risk of hip fracture than those with other chronic kidney diseases.Moreover,mice with osteoclastspecific knockout of Pkd1 showed complete resistance to unloading-induced bone loss.A mechanistic study revealed that PC1 facilitated TAZ nuclear translocation via the C-terminal tail-TAZ complex and that conditional deletion of Taz in the osteoclast lineage resulted in reduced osteoclastogenesis and increased bone mass.Pharmacological regulation of the PC1-TAZ axis alleviated unloading-and estrogen deficiency-induced bone loss.Thus,the PC1-TAZ axis may be a potential therapeutic target for osteoclast-related osteoporosis.展开更多
Mineral compositions of aerosol particles were investigated at four sites （Aksu, Dunhuang, Zhenbeitai, and Tongliao） in desert regions of northern China from March to May in 2001 and 2002 during the intensive field ...Mineral compositions of aerosol particles were investigated at four sites （Aksu, Dunhuang, Zhenbeitai, and Tongliao） in desert regions of northern China from March to May in 2001 and 2002 during the intensive field campaign period of ACE-Asia （Aerosol Characterization Experiments-Asia）. The X-ray diffraction （XRD） results show the main minerals for Asian dust are illite, chlorite, kaolinite, quartz, feldspar, calcite, and dolomite. Gypsum, hornblende, and halite are also detected in several samples. Semi-quantitative mineralogical data of aerosol samples show that carbonate content decreases from western to eastern source areas; that is, soil dust collected at western source area sites of Dunhuang and Aksu are enriched with carbonate, while northeastern source area site of Tongliao is associated with low carbonate content. But the spatial distribution of feldspar exhibits a different pattern as compared to carbonate, increasing from the western to the eastern sources. The total clay content is significantly higher （73% in average） at the deposition site of Changwu than those at source areas. Air-mass back trajectory studies for the three dust storm events observed at Changwu, showed that soil dust transport pathways were as expected from carbonate content for the source identification, further demonstrating that carbonate was a useful tracer for eolian dust on regional scale in northern China.展开更多
Surface weather parameters detain high socioeconomic impact and strategic insights for all users,in all domains(aviation,marine traffic,agriculture,etc.).However,those parameters were mainly predicted by using determi...Surface weather parameters detain high socioeconomic impact and strategic insights for all users,in all domains(aviation,marine traffic,agriculture,etc.).However,those parameters were mainly predicted by using deterministic numerical weather prediction(NWP)models that include a wealth of uncertainties.The purpose of this study is to contribute in improving low-cost computationally ensemble forecasting of those parameters using analog ensemble method(AnEn)and comparing it to the operational mesoscale deterministic model(AROME)all over the main airports of Morocco using 5-yr period(2016-2020)of hourly datasets.An analog for a given station and forecast lead time is a past prediction,from the same model that has similar values for selected predictors of the current model forecast.Best analogs verifying observations form AnEn ensemble members.To picture seasonal dependency,two configurations were set;a basic configuration where analogs may come from any past date and a restricted configuration where analogs should belong to a day window around the target forecast.Furthermore,a new predictors weighting strategy is developed by using machine learning techniques(linear regression,random forest,and XGBoost).This approach is expected to accomplish both the selection of relevant predictors as well as finding their optimal weights,and hence preserve physical meaning and correlations of the used weather variables.Results analysis shows that the developed AnEn system exhibits a good statistical consistency and it significantly improves the deterministic forecast performance temporally and spatially by up to 50%for Bias(mean error)and 30%for RMSE(root-mean-square error)at most of the airports.This improvement varies as a function of lead times and seasons compared to the AROME model and to the basic AnEn configuration.The results show also that AnEn performance is geographically dependent where a slight worsening is found for some airports.展开更多
Obesity-induced chronic inflammation exacerbates multiple types of tissue/organ deterioration and stem cell dysfunction;however,the effects on skeletal tissue and the underlying mechanisms are still unclear.Here,we sh...Obesity-induced chronic inflammation exacerbates multiple types of tissue/organ deterioration and stem cell dysfunction;however,the effects on skeletal tissue and the underlying mechanisms are still unclear.Here,we show that obesity triggers changes in the microRNA profile of macrophage-secreted extracellular vesicles,leading to a switch in skeletal stem/progenitor cell(SSPC)differentiation between osteoblasts and adipocytes and bone deterioration.Bone marrow macrophage(BMM)-secreted extracellular vesicles(BMM-EVs)from obese mice induced bone deterioration(decreased bone volume,bone microstructural deterioration,and increased adipocyte numbers)when administered to lean mice.Conversely,BMM-EVs from lean mice rejuvenated bone deterioration in obese recipients.We further screened the differentially expressed microRNAs in obese BMM-EVs and found that among the candidates,miR-140(with the function of promoting adipogenesis)and miR-378a(with the function of enhancing osteogenesis)coordinately determine SSPC fate of osteogenic and adipogenic differentiation by targeting the Pparα-Abca1 axis.BMM miR-140 conditional knockout mice showed resistance to obesity-induced bone deterioration,while miR-140 overexpression in SSPCs led to low bone mass and marrow adiposity in lean mice.BMM miR-378a conditional depletion in mice led to obesity-like bone deterioration.More importantly,we used an SSPC-specific targeting aptamer to precisely deliver miR-378a-3p-overloaded BMM-EVs to SSPCs via an aptamer-engineered extracellular vesicle delivery system,and this approach rescued bone deterioration in obese mice.Thus,our study reveals the critical role of BMMs in mediating obesity-induced bone deterioration by transporting selective extracellular-vesicle microRNAs into SSPCs and controlling SSPC fate.展开更多
基金supported by the Health and Medical Research Fund of the Food and Health Bureau of the Government of the Hong Kong Special Administrative Region(HMRF/19202461)by a direct grant(2022/044)from the Chinese University of Hong Kong.
文摘Background:Large Language Models(LLMs)have gained much attention and,in part,have replaced common search engines as a popular channel for obtaining information due to their contextually relevant responses.Osteoarthritis(OA)is a common topic in skeletal muscle disor-ders,and patients often seek information about it online.Our study evaluated the ability of 3 LLMs(ChatGPT-3.5,ChatGPT-4.0,and Perplexity)to accurately answer common OA-related queries.Methods:We defined 6 themes(pathogenesis,risk factors,clinical presentation,diagnosis,treatment and prevention,and prognosis)based on a generalization of 25 frequently asked questions about OA.Three consultant-level orthopedic specialists independently rated the LLMs’replies on a 4-point accuracy scale.Thefinal ratings for each response were determined using a majority consensus approach.Responses classified as“satisfactory”were evaluated for comprehensiveness on a 5-point scale.Results:ChatGPT-4.0 demonstrated superior accuracy,with 64%of responses rated as“excellent”,compared to 40%for ChatGPT-3.5 and 28%for Perplexity(Pearson’s x2 test with Fisher’s exact test,all p<0.001).All 3 LLM-chatbots had high mean comprehensiveness ratings(Perplexity=3.88;ChatGPT-4.0=4.56;ChatGPT-3.5=3.96,out of a maximum score of 5).The LLM-chatbots performed reliably across domains,except for“treatment and prevention”However,ChatGPT-4.0 still outperformed ChatGPT-3.5 and Perplexity,garnering 53.8%“excellent”ratings(Pearson’s x2 test with Fisher’s exact test,all p<0.001).Conclusion:Ourfindings underscore the potential of LLMs,specifically ChatGPT-4.0 and Perplexity,to deliver accurate and thorough responses to OA-related queries.Targeted correction of specific misconceptions to improve the accuracy of LLMs remains crucial.
基金funding from the Agence Nationale de la Recherche (ANR) [grant HIGH-TUNE ANR-16-CE01-0010]
文摘Models disagree on a significant number of responses to climate change,such as climate feedback,regional changes,or the strength of equilibrium climate sensitivity.Emergent constraints aim to reduce these uncertainties by finding links between the inter-model spread in an observable predictor and climate projections.In this paper,the concepts underlying this framework are recalled with an emphasis on the statistical inference used for narrowing uncertainties,and a review of emergent constraints found in the last two decades.Potential links between highlighted predictors are explored,especially those targeting uncertainty reductions in climate sensitivity,cloud feedback,and changes of the hydrological cycle.Yet the disagreement across emergent constraints suggests that the spread in climate sensitivity can not be significantly narrowed.This calls for weighting the realism of emergent constraints by quantifying the level of physical understanding explaining the relationship.This would also permit more efficient model evaluation and better targeted model development.In the context of the upcoming CMIP6 model intercomparison a growing number of new predictors and uncertainty reductions is expected,which call for robust statistical inferences that allow cross-validation of more likely estimates.
基金supported by grants from the National Key Project of Basic Research (2006CB403702 and 2006CB403701)the CAMS Basis Research Project and National Natural Science Foundation of China under Grant No. 40405001
文摘The aerosol optical properties and direct radiative forcing over the Mu Us desert of northern China, acquired through a CE318 sunphotometer of the ground-based Aerosol Robotic Network （AERONET）, are analyzed. The seasonal variations in the aerosol optical properties are examined. The effect of meteorological elements （pressure, temperature, water vapor pressure, relative humidity and wind speed） on the aerosol optical properties is also studied. Then, the sources and optical properties under two different cases, a dust event and a pollution event, are compared. The results show that the high aerosol optical depth （AOD） found in Yulin was mostly attributed to the occurrence of dust events in spring from the Mu Us desert and deserts of West China and Mongolia, as well as the impacts of anthropogenic pollutant particles from the middle part of China in the other seasons. The seasonal variation and the probability distribution of the radiative forcing and the radiative forcing efficiency at the surface and the top of the atmosphere are analyzed and regressed using the linear and Gaussian regression methods.
基金CGL2014-52599-P “Estudio del manto de nieve enla montana espanola y su respuesta a la variabilidad y cambio climatico” funded by the Spanish Ministry of Economy and CompetitivenessEl glaciar de Monte Perdido: estudio de su dinámica actual y procesos criosféricos asociados como indicadores de procesos de cambio global” (MAGRAMA 844/2013).
文摘This study demonstrated the usefulness of very long-range terrestrial laser scanning(TLS) for analysis of the spatial distribution of a snowpack, to distances up to 3000 m, one of the longest measurement range reported to date. Snow depth data were collected using a terrestrial laser scanner during 11 periods of snow accumulation and melting,over three snow seasons on a Pyrenean hillslopecharacterized by a large elevational gradient, steep slopes, and avalanche occurrence. The maximum and mean absolute snow depth error found was 0.5-0.6 and 0.2-0.3 m respectively, which may result problematic for areas with a shallow snowpack, but it is sufficiently accurate to determine snow distribution patterns in areas characterized by a thick snowpack. The results indicated that in most cases there was temporal consistency in the spatial distribution of thesnowpack, even in different years. The spatial patterns were particularly similar amongst thesurveys conducted during the period dominated by snow accumulation(generally until end of April), or amongst those conducted during the period dominated by melting processes(generally after mid of April or early May). Simple linear correlation analyses for the 11 survey dates, and the application of Random Forests analysis to two days representative of snow accumulation and melting periods indicated the importance of topography to the snow distribution. The results also highlight that elevation and the Topographic Position index(TPI) were the main variables explaining the snow distribution, especially during periods dominated by melting. The intra-and inter-annual spatial consistency of the snowpack distribution suggests that the geomorphological processes linked to presence/absence of snow cover act in a similar way in the long term, and that these spatial patternscan be easily identifiedthrough several years of adequate monitoring.
文摘A relationship between oceanic conditions in the northwestern equatorial Atlantic (NWEA) and the seasonal rainfall over the northern part of Brazilian Northeast (NNEB) allows large climate events to be forecasted with a delay of a few months. Observed sea surface variables (sea surface temperature, wind stress and latent heat flux) and reanalyzed temperature and salinity profiles at depths of 0 - 150 m are used during 1974-2008. Perturbations in the Wind-Evaporation-SST mechanism over the NWEA during the last months of the year and the first months of the following year are of primary importance in evaluating the risk that strong climate events will affect the subsequent seasonal rainfall (in March-April) over the NNEB. Especially interesting are the Barrier Layer Thickness (BLT) and Ocean Heat Content (OHC) in the NWEA region from August-September through the subsequent months, during which a slow and steady evolution is apparent, with the highest signal occurring in October-November. Through their relationship with the local surface dynamic conditions, such BLT and OHC perturbations during the last months of the year can be used as a valuable indicator for forecasting wet or dry events over the NNEB during the subsequent rainfall season. A proposal is discussed to deploy additional temperature/conductivity sensors down to a depth of 140 m at three PIRATA moorings located in the NWEA region. That will be necessary if the BLT and other parameters of energy exchange between the ocean and atmosphere are to be estimated in real time and with a sufficiently high vertical resolution.
基金supported by the National Key Research and Development Program of China(2019YFA0111900,2022YFC3601900 and 2022YFC2505500)the National Natural Science Foundation of China(82261160397,82272560,81922017,92149306 and 82120108009)+5 种基金the NSFC/RGC Joint Research Schemethe Research Grants Council(UGC)of the Hong Kong Special Administrative Region and the National Natural Science Foundation of China(N_CUHK483/22)the Center for Neuromusculoskeletal Restorative Medicine by Innovation and Technology Commission(ITC)of Hong Kong SAR,China(CNRM at Inno HK),the National Institutes of Health(R61-AR073518 and R01-AR071930)the Key Research and Development Program of Hunan Province(2022SK2023)the Science and Technology Innovation Program of Hunan Province(2023RC1027,2022RC1009 and 2022RC3075)the Hunan Provincial Science and Technology Department(2023JJ30896)。
文摘Mechanical loading is required for bone homeostasis,but the underlying mechanism is still unclear.Our previous studies revealed that the mechanical protein polycystin-1(PC1,encoded by Pkd1)is critical for bone formation.However,the role of PC1 in bone resorption is unknown.Here,we found that PC1directly regulates osteoclastogenesis and bone resorption.The conditional deletion of Pkd1 in the osteoclast lineage resulted in a reduced number of osteoclasts,decreased bone resorption,and increased bone mass.A cohort study of 32,500 patients further revealed that autosomal dominant polycystic kidney disease,which is mainly caused by loss-of-function mutation of the PKD1 gene,is associated with a lower risk of hip fracture than those with other chronic kidney diseases.Moreover,mice with osteoclastspecific knockout of Pkd1 showed complete resistance to unloading-induced bone loss.A mechanistic study revealed that PC1 facilitated TAZ nuclear translocation via the C-terminal tail-TAZ complex and that conditional deletion of Taz in the osteoclast lineage resulted in reduced osteoclastogenesis and increased bone mass.Pharmacological regulation of the PC1-TAZ axis alleviated unloading-and estrogen deficiency-induced bone loss.Thus,the PC1-TAZ axis may be a potential therapeutic target for osteoclast-related osteoporosis.
基金supported by the National Natural Science Foundation of China (Grants 40405023,40675081,and 40599422)a grant from SKLLQG,CASthe staff of Shaanxi Institute of Desert Research,and Aksu Water Balance Observatory of the Chinese Academy of Sciences for their support during sampling
文摘Mineral compositions of aerosol particles were investigated at four sites （Aksu, Dunhuang, Zhenbeitai, and Tongliao） in desert regions of northern China from March to May in 2001 and 2002 during the intensive field campaign period of ACE-Asia （Aerosol Characterization Experiments-Asia）. The X-ray diffraction （XRD） results show the main minerals for Asian dust are illite, chlorite, kaolinite, quartz, feldspar, calcite, and dolomite. Gypsum, hornblende, and halite are also detected in several samples. Semi-quantitative mineralogical data of aerosol samples show that carbonate content decreases from western to eastern source areas; that is, soil dust collected at western source area sites of Dunhuang and Aksu are enriched with carbonate, while northeastern source area site of Tongliao is associated with low carbonate content. But the spatial distribution of feldspar exhibits a different pattern as compared to carbonate, increasing from the western to the eastern sources. The total clay content is significantly higher （73% in average） at the deposition site of Changwu than those at source areas. Air-mass back trajectory studies for the three dust storm events observed at Changwu, showed that soil dust transport pathways were as expected from carbonate content for the source identification, further demonstrating that carbonate was a useful tracer for eolian dust on regional scale in northern China.
文摘Surface weather parameters detain high socioeconomic impact and strategic insights for all users,in all domains(aviation,marine traffic,agriculture,etc.).However,those parameters were mainly predicted by using deterministic numerical weather prediction(NWP)models that include a wealth of uncertainties.The purpose of this study is to contribute in improving low-cost computationally ensemble forecasting of those parameters using analog ensemble method(AnEn)and comparing it to the operational mesoscale deterministic model(AROME)all over the main airports of Morocco using 5-yr period(2016-2020)of hourly datasets.An analog for a given station and forecast lead time is a past prediction,from the same model that has similar values for selected predictors of the current model forecast.Best analogs verifying observations form AnEn ensemble members.To picture seasonal dependency,two configurations were set;a basic configuration where analogs may come from any past date and a restricted configuration where analogs should belong to a day window around the target forecast.Furthermore,a new predictors weighting strategy is developed by using machine learning techniques(linear regression,random forest,and XGBoost).This approach is expected to accomplish both the selection of relevant predictors as well as finding their optimal weights,and hence preserve physical meaning and correlations of the used weather variables.Results analysis shows that the developed AnEn system exhibits a good statistical consistency and it significantly improves the deterministic forecast performance temporally and spatially by up to 50%for Bias(mean error)and 30%for RMSE(root-mean-square error)at most of the airports.This improvement varies as a function of lead times and seasons compared to the AROME model and to the basic AnEn configuration.The results show also that AnEn performance is geographically dependent where a slight worsening is found for some airports.
基金supported by the National Key R&D Program of China(Grant 2022YFC3601900 to G.H.L.,2022YFC3601903,and 2022YFC3601905 to C.J.L.,2019YFA0111900 to Y.J.)the National Natural Science Foundation of China(Grant Nos.82261160397,82272560,81922017 to C.J.L.)+4 种基金the Hunan Provincial Science and Technology Department(2023JJ30896 to C.J.L.,2023JJ40965 to L.L.)the Key Research and Development Program of Hunan Province(2022SK2023 to C.J.L.)Science and Technology Innovation Program of Hunan Province(2023RC1027 to C.J.L.,2022RC1009 to J.W.,and 2022RC3075 to C.Z.)The NSFC/RGC Joint Research Scheme,the Research Grants Council(UGC)of the Hong Kong Special Administrative Region and the National Natural Science Foundation of China(NSFC/RGC Project No.N_CUHK483/22 to Y.J.)the Center for Neuromusculoskeletal Restorative Medicine[CNRM at InnoHK,to Y.J.]by Innovation and Technology Commission(ITC)of Hong Kong SAR,China.
文摘Obesity-induced chronic inflammation exacerbates multiple types of tissue/organ deterioration and stem cell dysfunction;however,the effects on skeletal tissue and the underlying mechanisms are still unclear.Here,we show that obesity triggers changes in the microRNA profile of macrophage-secreted extracellular vesicles,leading to a switch in skeletal stem/progenitor cell(SSPC)differentiation between osteoblasts and adipocytes and bone deterioration.Bone marrow macrophage(BMM)-secreted extracellular vesicles(BMM-EVs)from obese mice induced bone deterioration(decreased bone volume,bone microstructural deterioration,and increased adipocyte numbers)when administered to lean mice.Conversely,BMM-EVs from lean mice rejuvenated bone deterioration in obese recipients.We further screened the differentially expressed microRNAs in obese BMM-EVs and found that among the candidates,miR-140(with the function of promoting adipogenesis)and miR-378a(with the function of enhancing osteogenesis)coordinately determine SSPC fate of osteogenic and adipogenic differentiation by targeting the Pparα-Abca1 axis.BMM miR-140 conditional knockout mice showed resistance to obesity-induced bone deterioration,while miR-140 overexpression in SSPCs led to low bone mass and marrow adiposity in lean mice.BMM miR-378a conditional depletion in mice led to obesity-like bone deterioration.More importantly,we used an SSPC-specific targeting aptamer to precisely deliver miR-378a-3p-overloaded BMM-EVs to SSPCs via an aptamer-engineered extracellular vesicle delivery system,and this approach rescued bone deterioration in obese mice.Thus,our study reveals the critical role of BMMs in mediating obesity-induced bone deterioration by transporting selective extracellular-vesicle microRNAs into SSPCs and controlling SSPC fate.
