In dendroclimatology,tree ring chronology is ordinarily established to reveal the fluctuation law of climate change on the interannual,interdecadal,and centennial scales.However,since traditional dendrochronology can ...In dendroclimatology,tree ring chronology is ordinarily established to reveal the fluctuation law of climate change on the interannual,interdecadal,and centennial scales.However,since traditional dendrochronology can only use one variable(tree ring width)to reflect environmentally related information,this causes the richer information recorded in the tree rings to be discarded.In this study,we examined the potential of hyperspectral chronological indices(shortened as“hyperspectral index/indices”)with samples collected in Shennongjia woodland in central China.The correlation analysis of the tree ring series on different samples indicated that hyperspectral indices outperform the traditional width index in chronology statistics including Signal-to-noise Ratio(SNR)and Expressed Population Signal(EPS).The reliability test shows that hyperspectral chronologies have more periods reaching the threshold of EPS or Subsample Signal Strength(SSS)>0.85,which means that hyperspectral chronologies provide more reliable periods for accurate climate reconstruction.Based on this,chronologies built by the three dendroclimatic indices were used to reconstruct the average temperature changes in Shennongjia over the last 103 years.The reconstruction results indicate that in our study area,the traditional width index model failed the split-sample calibration test and exhibited a low reconstruction accuracy,while the hyperspectral index model has a higher explained variance of 46.4%(p<0.01),compared to the width index(21.4%)and the grayscale index(38.3%).Our research results show that hyperspectral indices have greater potential for climate reconstruction in regions with lower susceptibility to climate stress.This is attributed to their ability to effectively extract subtle climate signals from the spectral variations on the surface of tree rings.Such ring spectral changes may be caused by complex and currently unknown responses of the trees to the climate.展开更多
Resource-rich shale gas plays a pivotal role in new energy types.The key to scientifically and efficiently developing shale gas fields is to clarify the main factors that affect the production of shale gas wells.In th...Resource-rich shale gas plays a pivotal role in new energy types.The key to scientifically and efficiently developing shale gas fields is to clarify the main factors that affect the production of shale gas wells.In this paper,according to the shale gas reservoir characteristic of the Fuling marine Longmaxi Formation,a single-well geological model was established using the reservoir numerical simulation software CMG.Then,10,000 different reservoir models were randomly generated for different formation physical parameters,completion parameters,and fracturing parameters using the Monte Carlo method,and these 10,000 models were simulated numerically.The machine learning model uses a dataset of 10,000 different geological,completion,and fracturing parameters as input and 10,000 production curves as output.Multiple machine learning regression methods were used to train and test the dataset,and the optimal method(GBDT algorithm)was selected,and the accuracy R2 of the test set of the GBDT prediction model is 0.96.A fracturing parameter optimization workflow was constructed by combining a production prediction model with a particle swarm optimizer(PSO).The process can quickly optimize the fracturing parameters and predict the production for each time by targeting the cumulative gas production under different geological conditions.The optimized parameters are Fracture Spacing,Fracture Width,Intrinsic Permeability,Fracture Half-length,Langmuir Pressure,and Langmuir Volume.The initial predicted cumulative gas production was 4.59×10^(8)m^(3),which was optimized to 4.90×10^(8) m^(3).The proposed PSO-GBDT proxy model can instantly predict the production of shale gas wells with considerable accuracy,reliability,and efficiency,which is a vital tool for optimizing fracture design.This investigation provides a solid foundation for predicting the production of unconventional gas reservoirs and for parameter optimization.展开更多
The loss of endothelial connective integrity and endothelial barrier dysfunction can lead to increased vascular injury, which is related to the activation of endothelial inflammasomes. There are evidences that low con...The loss of endothelial connective integrity and endothelial barrier dysfunction can lead to increased vascular injury, which is related to the activation of endothelial inflammasomes. There are evidences that low concentrations of aspirin can effectively prevent cardiovascular diseases. We hypothesized that low-dose aspirin could ameliorate endothelial injury by inhibiting the activation of NLRP3 inflammasomes and ultimately prevent cardiovascular diseases. Microvascular endothelial cells were stimulated by lipopolysaccharide(2 μg/mL) and administrated by 0.1–2 mmol/L aspirin. The wild type mice were stimulated with LPS(100 μg/kg/day), and 1 h later treated with aspirin(12.5, 62.5, or125 mg/kg/day) and dexamethasone(0.0182 mg/kg/day) for 7 days. Plasma and heart were harvested for measurement of ELISA and immunofluorescence analyses. We found that aspirin could inhibit NLRP3 inflammasome formation and activation in vitro in dose-dependent manner and has correlation between the NLRP3 inflammasome and the ROS/TXNIP pathway. We also found that low-concentration aspirin could inhibit the formation and activation of NLRP3 inflammasome and restore the expression of theendothelial tight junction protein zonula occludens-1/2(ZO1/2). We assume that aspirin can ameliorate the endothelial layer dysfunction by suppressing the activation of NLRP3 inflammasome.展开更多
Myeloid-derived suppressor cells(MDSCs)are a heterogeneous population of immature cells and natural inhibitors of adaptive immunity.Intracellular metabolic changes in MDSCs exert a direct immunological influence on th...Myeloid-derived suppressor cells(MDSCs)are a heterogeneous population of immature cells and natural inhibitors of adaptive immunity.Intracellular metabolic changes in MDSCs exert a direct immunological influence on their suppressive activity.Our previous study demonstrated that high-dose dexamethasone(HD-DXM)corrected the functional impairment of MDSCs in immune thrombocytopenia(ITP);however,the MDSC population was not restored in nonresponders,and the mechanism remained unclear.In this study,altered mitochondrial physiology and reduced mitochondrial gene transcription were detected in MDSCs from HD-DXM nonresponders,accompanied by decreased levels of carnitine palmitoyltransferase-1(CPT-1),a rate-limiting enzyme in fatty acid oxidation(FAO).Blockade of FAO with a CPT-1 inhibitor abolished the immunosuppressive function of MDSCs in HD-DXM responders.We also report that MDSCs from ITP patients had lower expression of the glucocorticoid receptor(GR),which can translocate into mitochondria to regulate the transcription of mitochondrial DNA(mtDNA)as well as the level of oxidative phosphorylation.It was confirmed that the expression of CPT-1 and mtDNA-encoded genes was downregulated in GR-siRNA-treated murine MDSCs.Finally,by establishing murine models of active and passive ITP via adoptive transfer of DXM-modulated MDSCs,we confirmed that GR-silenced MDSCs failed to alleviate thrombocytopenia in mice with ITP.In conclusion,our study indicated that impaired aerobic metabolism in MDSCs participates in the pathogenesis of glucocorticoid resistance in ITP and that intact control of MDSC metabolism by GR contributes to the homeostatic regulation of immunosuppressive cell function.展开更多
Spinal cord injury(SCI)often results in an inhibitory environment at the injury site.In our previous studies,transplantation of a scaffold combined with stem cells was proven to induce neural regeneration in animal mo...Spinal cord injury(SCI)often results in an inhibitory environment at the injury site.In our previous studies,transplantation of a scaffold combined with stem cells was proven to induce neural regeneration in animal models of complete SCI.Based on these preclinical studies,collagen scaffolds loaded with the patients’own bone marrow mononuclear cells or human umbilical cord mesenchymal stem cells were transplanted into SCI patients.Fifteen patients with acute complete SCI and 51 patients with chronic complete SCI were enrolled and followed up for 2 to 5 years.No serious adverse events related to functional scaffold transplantation were observed.Among the patients with acute SCI,five patients achieved expansion of their sensory positions and six patients recovered sensation in the bowel or bladder.Additionally,four patients regained voluntary walking ability accompanied by reconnection of neural signal transduction.Among patients with chronic SCI,16 patients achieved expansion of their sensation level and 30 patients experienced enhanced reflexive defecation sensation or increased skin sweating below the injury site.Nearly half of the patients with chronic cervical SCI developed enhanced finger activity.These long-term follow-up results suggest that functional scaffold transplantation may represent a feasible treatment for patients with complete SCI.展开更多
基金supported by the National Natural Science Foundation of China(NSFC)Projects[grant numbers 42271476 and 41771227]Key Technology Projects of the Hubei Provincial Company of the China National Tobacco Corporation(grant number 027Y2021-020 and 027Y2022-006)Young Scholar of Wuhan University 351 Talent Program[grant number 202017].
文摘In dendroclimatology,tree ring chronology is ordinarily established to reveal the fluctuation law of climate change on the interannual,interdecadal,and centennial scales.However,since traditional dendrochronology can only use one variable(tree ring width)to reflect environmentally related information,this causes the richer information recorded in the tree rings to be discarded.In this study,we examined the potential of hyperspectral chronological indices(shortened as“hyperspectral index/indices”)with samples collected in Shennongjia woodland in central China.The correlation analysis of the tree ring series on different samples indicated that hyperspectral indices outperform the traditional width index in chronology statistics including Signal-to-noise Ratio(SNR)and Expressed Population Signal(EPS).The reliability test shows that hyperspectral chronologies have more periods reaching the threshold of EPS or Subsample Signal Strength(SSS)>0.85,which means that hyperspectral chronologies provide more reliable periods for accurate climate reconstruction.Based on this,chronologies built by the three dendroclimatic indices were used to reconstruct the average temperature changes in Shennongjia over the last 103 years.The reconstruction results indicate that in our study area,the traditional width index model failed the split-sample calibration test and exhibited a low reconstruction accuracy,while the hyperspectral index model has a higher explained variance of 46.4%(p<0.01),compared to the width index(21.4%)and the grayscale index(38.3%).Our research results show that hyperspectral indices have greater potential for climate reconstruction in regions with lower susceptibility to climate stress.This is attributed to their ability to effectively extract subtle climate signals from the spectral variations on the surface of tree rings.Such ring spectral changes may be caused by complex and currently unknown responses of the trees to the climate.
基金Xi’an Shiyou University for funding the Graduate Student Innovation and Practical Skills Training Program(No.YCS21213174).
文摘Resource-rich shale gas plays a pivotal role in new energy types.The key to scientifically and efficiently developing shale gas fields is to clarify the main factors that affect the production of shale gas wells.In this paper,according to the shale gas reservoir characteristic of the Fuling marine Longmaxi Formation,a single-well geological model was established using the reservoir numerical simulation software CMG.Then,10,000 different reservoir models were randomly generated for different formation physical parameters,completion parameters,and fracturing parameters using the Monte Carlo method,and these 10,000 models were simulated numerically.The machine learning model uses a dataset of 10,000 different geological,completion,and fracturing parameters as input and 10,000 production curves as output.Multiple machine learning regression methods were used to train and test the dataset,and the optimal method(GBDT algorithm)was selected,and the accuracy R2 of the test set of the GBDT prediction model is 0.96.A fracturing parameter optimization workflow was constructed by combining a production prediction model with a particle swarm optimizer(PSO).The process can quickly optimize the fracturing parameters and predict the production for each time by targeting the cumulative gas production under different geological conditions.The optimized parameters are Fracture Spacing,Fracture Width,Intrinsic Permeability,Fracture Half-length,Langmuir Pressure,and Langmuir Volume.The initial predicted cumulative gas production was 4.59×10^(8)m^(3),which was optimized to 4.90×10^(8) m^(3).The proposed PSO-GBDT proxy model can instantly predict the production of shale gas wells with considerable accuracy,reliability,and efficiency,which is a vital tool for optimizing fracture design.This investigation provides a solid foundation for predicting the production of unconventional gas reservoirs and for parameter optimization.
基金supported by the National Key Research and Development Program of China(No.2017YFC1700400)National Natural Science Foundation of China(Nos.81603587 and 81603668)+4 种基金Guangdong Natural Science Funds for Distinguished Young Scholar(No.2018B030306027,China)Science and Technology Development Plan of Guangdong Province(2017A020211016,China)Science&Technology Award for Young-Aged Talents of China Association of Traditional Chinese Medicine(No.CACM-2017-QNRC2-C12)the National Institutes of Health of USA(No.HL122769)Project of Guangzhou University of Chinese Medicine(No.A1-AFD018171Z11020,China)
文摘The loss of endothelial connective integrity and endothelial barrier dysfunction can lead to increased vascular injury, which is related to the activation of endothelial inflammasomes. There are evidences that low concentrations of aspirin can effectively prevent cardiovascular diseases. We hypothesized that low-dose aspirin could ameliorate endothelial injury by inhibiting the activation of NLRP3 inflammasomes and ultimately prevent cardiovascular diseases. Microvascular endothelial cells were stimulated by lipopolysaccharide(2 μg/mL) and administrated by 0.1–2 mmol/L aspirin. The wild type mice were stimulated with LPS(100 μg/kg/day), and 1 h later treated with aspirin(12.5, 62.5, or125 mg/kg/day) and dexamethasone(0.0182 mg/kg/day) for 7 days. Plasma and heart were harvested for measurement of ELISA and immunofluorescence analyses. We found that aspirin could inhibit NLRP3 inflammasome formation and activation in vitro in dose-dependent manner and has correlation between the NLRP3 inflammasome and the ROS/TXNIP pathway. We also found that low-concentration aspirin could inhibit the formation and activation of NLRP3 inflammasome and restore the expression of theendothelial tight junction protein zonula occludens-1/2(ZO1/2). We assume that aspirin can ameliorate the endothelial layer dysfunction by suppressing the activation of NLRP3 inflammasome.
基金This work was supported by grants from the National Natural Science Foundation of China(Nos.81900121,81770133,81973994,and 81770114)Major Research Plan of National Natural Science Foundation of China(No.91942306)+3 种基金Clinical Research Center of Shandong University(No.2020SDUCRCC009)Graduate Education Reform Project of Shandong University(No.XYJG2020141)State Key Clinical Specialty of China for Blood DisordersYoung Taishan Scholar Foundation of Shandong Province(No.tsqn201909175).
文摘Myeloid-derived suppressor cells(MDSCs)are a heterogeneous population of immature cells and natural inhibitors of adaptive immunity.Intracellular metabolic changes in MDSCs exert a direct immunological influence on their suppressive activity.Our previous study demonstrated that high-dose dexamethasone(HD-DXM)corrected the functional impairment of MDSCs in immune thrombocytopenia(ITP);however,the MDSC population was not restored in nonresponders,and the mechanism remained unclear.In this study,altered mitochondrial physiology and reduced mitochondrial gene transcription were detected in MDSCs from HD-DXM nonresponders,accompanied by decreased levels of carnitine palmitoyltransferase-1(CPT-1),a rate-limiting enzyme in fatty acid oxidation(FAO).Blockade of FAO with a CPT-1 inhibitor abolished the immunosuppressive function of MDSCs in HD-DXM responders.We also report that MDSCs from ITP patients had lower expression of the glucocorticoid receptor(GR),which can translocate into mitochondria to regulate the transcription of mitochondrial DNA(mtDNA)as well as the level of oxidative phosphorylation.It was confirmed that the expression of CPT-1 and mtDNA-encoded genes was downregulated in GR-siRNA-treated murine MDSCs.Finally,by establishing murine models of active and passive ITP via adoptive transfer of DXM-modulated MDSCs,we confirmed that GR-silenced MDSCs failed to alleviate thrombocytopenia in mice with ITP.In conclusion,our study indicated that impaired aerobic metabolism in MDSCs participates in the pathogenesis of glucocorticoid resistance in ITP and that intact control of MDSC metabolism by GR contributes to the homeostatic regulation of immunosuppressive cell function.
基金supported by grants from the National Natural Science Foundation of China(81891000)the National Key Research and Development Program of China(2016YFC1101504 and2016YFC1101505)。
文摘Spinal cord injury(SCI)often results in an inhibitory environment at the injury site.In our previous studies,transplantation of a scaffold combined with stem cells was proven to induce neural regeneration in animal models of complete SCI.Based on these preclinical studies,collagen scaffolds loaded with the patients’own bone marrow mononuclear cells or human umbilical cord mesenchymal stem cells were transplanted into SCI patients.Fifteen patients with acute complete SCI and 51 patients with chronic complete SCI were enrolled and followed up for 2 to 5 years.No serious adverse events related to functional scaffold transplantation were observed.Among the patients with acute SCI,five patients achieved expansion of their sensory positions and six patients recovered sensation in the bowel or bladder.Additionally,four patients regained voluntary walking ability accompanied by reconnection of neural signal transduction.Among patients with chronic SCI,16 patients achieved expansion of their sensation level and 30 patients experienced enhanced reflexive defecation sensation or increased skin sweating below the injury site.Nearly half of the patients with chronic cervical SCI developed enhanced finger activity.These long-term follow-up results suggest that functional scaffold transplantation may represent a feasible treatment for patients with complete SCI.
