Sonic Hedgehog(SHH)信号转导途径,作为调控胚胎发育和组织稳态的重要途径,近年来被发现通过多种机制参与心肌梗死后血管的再生过程。本文系统性地回顾了SHH通路的核心分子机制及其在血管再生中的作用。这些发现为未来针对心肌梗死后血...Sonic Hedgehog(SHH)信号转导途径,作为调控胚胎发育和组织稳态的重要途径,近年来被发现通过多种机制参与心肌梗死后血管的再生过程。本文系统性地回顾了SHH通路的核心分子机制及其在血管再生中的作用。这些发现为未来针对心肌梗死后血管再生的精准干预提供了潜在的靶点。展开更多
Graphene nanoplatelets(GNPs)have attracted tremendous interest due to their unique properties and bonding capabilities.This study focuses on the effect of GNP dispersion on the mechanical,thermal,and morphological beh...Graphene nanoplatelets(GNPs)have attracted tremendous interest due to their unique properties and bonding capabilities.This study focuses on the effect of GNP dispersion on the mechanical,thermal,and morphological behavior of GNP/epoxy nanocomposites.This study aims to understand how the dispersion of GNPs affects the properties of epoxy nanocomposite and to identify the best dispersion approach for improving mechanical performance.A solvent mixing technique that includes mechanical stirring and ultrasonication was used for producing the nanocomposites.Fourier transform infrared spectroscopy was used to investigate the interaction between GNPs and the epoxy matrix.The measurements of density and moisture content were used to confirm that GNPs were successfully incorporated into the nanocomposite.The findings showed that GNPs are successfully dispersed in the epoxy matrix by combining mechanical stirring and ultrasonication in a single step,producing well-dispersed nanocomposites with improved mechanical properties.Particularly,the nanocomposites at a low GNP loading of 0.1 wt%,demonstrate superior mechanical strength,as shown by increased tensile properties,including improved Young's modulus(1.86 GPa),strength(57.31 MPa),and elongation at break(4.98).The nanocomposite with 0.25 wt%GNP loading performs better,according to the viscoelastic analysis and flexural properties(113.18 MPa).Except for the nanocomposite with a 0.5 wt%GNP loading,which has a higher thermal breakdown temperature,the thermal characteristics do not significantly alter.The effective dispersion of GNPs in the epoxy matrix and low agglomeration is confirmed by the morphological characterization.The findings help with filler selection and identifying the best dispersion approach,which improves mechanical performance.The effective integration of GNPs and their interaction with the epoxy matrix provides the doorway for additional investigation and the development of sophisticated nanocomposites.In fields like aerospace,automotive,and electronics where higher mechanical performance and functionality are required,GNPs'improved mechanical properties and successful dispersion present exciting potential.展开更多
Periodontal disease is a risk factor for many systemic diseases such as Alzheimer’s disease and adverse pregnancy outcomes.Cleft palate(CP),the most common congenital craniofacial defect,has a multifaceted etiology i...Periodontal disease is a risk factor for many systemic diseases such as Alzheimer’s disease and adverse pregnancy outcomes.Cleft palate(CP),the most common congenital craniofacial defect,has a multifaceted etiology influenced by complex genetic and environmental risk factors such as maternal bacterial or virus infection.A prior case-control study revealed a surprisingly strong association between maternal periodontal disease and CP in offspring.However,the precise relationship remains unclear.In this study,the relationship between maternal oral pathogen and CP in offspring was studied by sonicated P.gingivalis injected intravenously and orally into pregnant mice.We investigated an obvious increasing CP(12.5%)in sonicated P.gingivalis group which had inhibited osteogenesis in mesenchyme and blocked efferocytosis in epithelium.Then glycolysis and H4K12 lactylation(H4K12la)were detected to elevate in both mouse embryonic palatal mesenchyme(MEPM)cells and macrophages under P.gingivalis exposure which further promoted the transcription of metallopeptidase domain17(ADAM17),subsequently mediated the shedding of transforming growth factor-beta receptor 1(TGFBR1)in MEPM cells and mer tyrosine kinase(MerTK)in macrophages and resulted in the suppression of efferocytosis and osteogenesis in palate,eventually caused abnormalities in palate fusion and ossification.The abnormal efferocytosis also led to a predominance of M1 macrophages,which indirectly inhibited palatal osteogenesis via extracellular vesicles.Furthermore,pharmacological ADAM17 inhibition could ameliorate the abnormality of P.gingivalis-induced abnormal palate development.Therefore,our study extends the knowledge of how maternal oral pathogen affects fetal palate development and provides a novel perspective to understand the pathogenesis of CP.展开更多
Recent studies have shown that fibrotic scar formation following cerebral ischemic injury has varying effects depending on the microenvironment.However,little is known about how fibrosis is induced and regulated after...Recent studies have shown that fibrotic scar formation following cerebral ischemic injury has varying effects depending on the microenvironment.However,little is known about how fibrosis is induced and regulated after cerebral ischemic injury.Sonic hedgehog signaling participates in fibrosis in the heart,liver,lung,and kidney.Whether Shh signaling modulates fibrotic scar formation after cerebral ischemic stroke and the underlying mechanisms are unclear.In this study,we found that Sonic Hedgehog expression was upregulated in patients with acute ischemic stroke and in a middle cerebral artery occlusion/reperfusion injury rat model.Both Sonic hedgehog and Mitofusin 2 showed increased expression in the middle cerebral artery occlusion rat model and in vitro fibrosis cell model induced by transforming growth factor-beta 1.Activation of the Sonic hedgehog signaling pathway enhanced the expression of phosphorylated Smad 3 and Mitofusin 2 proteins,promoted the formation of fibrotic scars,protected synapses or promoted synaptogenesis,alleviated neurological deficits following middle cerebral artery occlusion/reperfusion injury,reduced cell apoptosis,facilitated the transformation of meninges fibroblasts into myofibroblasts,and enhanced the proliferation and migration of meninges fibroblasts.The Smad3 phosphorylation inhibitor SIS3 reversed the effects induced by Sonic hedgehog signaling pathway activation.Bioinformatics analysis revealed significant correlations between Sonic hedgehog and Smad3,between Sonic hedgehog and Mitofusin 2,and between Smad3 and Mitofusin 2.These findings suggest that Sonic hedgehog signaling may influence Mitofusin 2 expression by regulating Smad3 phosphorylation,thereby modulating the formation of early fibrotic scars following cerebral ischemic stroke and affecting prognosis.The Sonic Hedgehog signaling pathway may serve as a new therapeutic target for stroke treatment.展开更多
传统互联网为实现端到端安全、可靠、实时的网络业务保障,需要在网元节点部署多类组网服务。然而,现有大多数网络设备只提供网络接入和路由等服务功能,缺乏安全、可靠、实时的服务设计。基于开源网络操作系统(software for open network...传统互联网为实现端到端安全、可靠、实时的网络业务保障,需要在网元节点部署多类组网服务。然而,现有大多数网络设备只提供网络接入和路由等服务功能,缺乏安全、可靠、实时的服务设计。基于开源网络操作系统(software for open networking in the cloud,SONiC)、容器技术和行为树设计一种组网服务管控架构及调度方法,实现面向网络业务保障的组网服务部署,将组网服务部署可编程网络设备进行统一管理和调度,并进行仿真测试。所述组网服务管控架构及调度方法进一步增强了网络设备能力,利用行为树高效协调管控调度过程中的状态转化,保障组网服务的交付质量。展开更多
Striatal interneurons play a key role in modulating striatal-dependent behaviors,including motor activity and reward and emotional processing.Interneurons not only provide modulation to the basal ganglia circuitry und...Striatal interneurons play a key role in modulating striatal-dependent behaviors,including motor activity and reward and emotional processing.Interneurons not only provide modulation to the basal ganglia circuitry under homeostasis but are also involved in changes to plasticity and adaptation during disease conditions such as Parkinson's or Huntington's disease.This review aims to summarize recent findings regarding the role of striatal cholinergic and GABAergic interneurons in providing circuit modulation to the basal ganglia in both homeostatic and disease conditions.In addition to direct circuit modulation,striatal interneurons have also been shown to provide trophic support to maintain neuron populations in adulthood.We discuss this interesting and novel role of striatal interneurons,with a focus on the maintenance of adult dopaminergic neurons from interneuronderived sonic-hedgehog.展开更多
During the Indian National Gas Hydrate Program(NGHP)Expedition 02,Logging-while-drilling(LWD)logs were acquired at three sites(NGHP-02-11,NGHP-02-12,and NGHP-02-13)across the Mahanadi Basin in area A.We applied rock p...During the Indian National Gas Hydrate Program(NGHP)Expedition 02,Logging-while-drilling(LWD)logs were acquired at three sites(NGHP-02-11,NGHP-02-12,and NGHP-02-13)across the Mahanadi Basin in area A.We applied rock physics theory to available sonic velocity logs to know the distribution of gas hydrate at site NGHP-02-11 and NGHP-02-13.Rock physics modeling using sonic velocity at well location shows that gas hydrate is distributed mainly within the depth intervals of 150-265 m and 100 -215 mbsf at site NGHP-02-11 and NGHP-02-13,respectively,with an average saturation of about 4%of the pore space and the maximum concentration of about 40%of the pore space at 250 m depth at site NGHP-02-11,and at site NGHP-02-13 an average saturation of about 2%of the pore space and the maximum concentration of about 20%of the pore space at 246 m depth,as gas hydrate is distributed mainly within 100-246 mbsf at this site.Saturation of gas hydrate estimated from the electrical resistivity method using density derived porosity and electrical resistivity logs from Archie's empirical formula shows high saturation compared to that from the sonic log.However,estimates of hydrate saturation based on sonic P-wave velocity may differ significantly from that based on resistivity,because gas and hydrate have higher resistivity than conductive pore fluid and sonic P-wave velocity shows strong effect on gas hydrate as a small amount of gas reduces the velocity significantly while increasing velocity due to the presence of hydrate.At site NGHP-02-11,gas hydrate saturation is in the range of 15%e30%,in two zones between 150-180 and 245-265 mbsf.Site NGHP-02-012 shows a gas hydrate saturation of 20%e30%in the zone between 100 and 207 mbsf.Site NGHP-02-13 shows a gas hydrate saturation up to 30%in the zone between 215 and 246 mbsf.Combined observations from rock physics modeling and Archie’s approximation show the gas hydrate concentrations are relatively low(<4%of the pore space)at the sites of the Mahanadi Basin in the turbidite channel system.展开更多
Background:The biomechanical environment created by suture-button fixation Latarjet is conducive to the healing and shaping of the transplanted coracoid,but its mechanism remains unclear.The latest research has found ...Background:The biomechanical environment created by suture-button fixation Latarjet is conducive to the healing and shaping of the transplanted coracoid,but its mechanism remains unclear.The latest research has found that the absence of stem cell chemokine(CXCL12)impeded bone regeneration in Sonic Hedgehog(SHH)-deficient animals.However,whether the biomechanical environment affects SHH and CXCL12 function has not been studied.Methods:Rat fracture models were constructed to simulate stress environments under non-l oad-bearing and load-bearing conditions.The fracture healing and shaping,as well as the expression levels of SHH and CXCL12,were assessed through gross viewing,micro-computed tomography(micro-CT),and histochemical staining.Results:Under flexible fixation,the relative bone volume(BV/TV)of rats exposed to the load-bearing stress environment was significantly higher than that of rats under a non-l oad-bearing stress environment(p≤0.05).Adverse bone shaping was not observed in rats subjected to flexible fixation.The levels of SHH and CXCL12in load-bearing rats exhibited significant elevation(p≤0.05).Under a load-bearing stress environment,no significant difference was observed in the BV/TV between the flexible fixation group and the rigid fixation group(p≥0.05),but there was excessive hyperplasia of the fracture callus in the rigid fixation group.The levels of SHH and CXCL12 in rats subjected to rigid fixation were significantly elevated(p≤0.05).Conclusions:Flexible fixation and load-bearing stress environment may contribute to bone healing and shaping by influencing the levels of SHH and CXCL12,suggested that this mechanism may be relevant to the healing and shaping of the transplanted coracoid after suture-button fixation Latarjet.展开更多
Qingshankou shale(Gulong area,China)exhibits strong acoustic anisotropy characteristics,posing significant challenges to its exploration and development.In this study,the five full elastic constants and multipole resp...Qingshankou shale(Gulong area,China)exhibits strong acoustic anisotropy characteristics,posing significant challenges to its exploration and development.In this study,the five full elastic constants and multipole response law of the Qingshankou shale were studied using experimental measurements.Analyses show that the anisotropy parametersϵandγin the study region are greater than 0.4,whereas the anisotropy parameterδis smaller,generally 0.1.Numerical simulations show that the longitudinal and transverse wave velocities of these strong anisotropic rocks vary significantly with inclination angle,and significant differences in group velocity and phase velocity are also present.Acoustic logging measures the group velocity in dipped boreholes;this differs from the phase velocity to some extent.As the dip angle increases,the longitudinal and SH wave velocities increase accordingly,while the qSV-wave velocity initially increases and then decreases,reaching its maximum value at a dip of approximately 40°.These results provide an effective guide for the correction and modeling of acoustic logging time differences in the region.展开更多
AIM:To investigate the effects of Sonic hedgehog(Shh)gene-modified bone marrow mesenchymal stem cells(MSCs)on graft-induced retinal gliosis and retinal ganglion cells(RGCs)survival in diabetic mice.METHODS:Bone marrow...AIM:To investigate the effects of Sonic hedgehog(Shh)gene-modified bone marrow mesenchymal stem cells(MSCs)on graft-induced retinal gliosis and retinal ganglion cells(RGCs)survival in diabetic mice.METHODS:Bone marrow-derived MSCs were genetically modified with the Shh gene to generate a stably transfected cell line of Shh-modified MSCs(MSC-Shh).Intravitreal injections of MSC-Shh and green fluorescent protein-modified MSCs(MSC-Gfp;control)were administered in diabetic mice.After 4wk,the effects of MSC-Shh on retinal gliosis were evaluated using fundus photography,and markers of gliosis were examined by immunofluorescence and Western blotting.The neurotrophic factors expression and RGCs survival in the host retina were evaluated using Western blotting and immunofluorescence.The mechanisms underlying the effects of MSC-Shh was investigated.RESULTS:A significant reduction of proliferative vitreoretinopathy(PVR)was observed after intravitreal injection of MSC-Shh compared to MSC-Gfp.Significant downregulation of glial fibrillary acidic protein(GFAP)was demonstrated in the host retina after MSC-Shh administration compared to MSC-Gfp.The extracellular signal-regulated kinase 1/2(ERK1/2),protein kinase B(AKT)and phosphatidylin-ositol-3-kinase(PI3K)pathways were significantly downregulated after MSC-Shh administration compared to MSC-Gfp.Brain-derived neurotrophic factor(BDNF)and ciliary neurotrophic factor(CNTF)levels were significantly increased in the host retina,and RGCs loss was significantly prevented after MSC-Shh administration.CONCLUSION:MSC-Shh administration reduces graft-induced reactive gliosis following intravitreal injection in diabetic mice.The ERK1/2,AKT and PI3K pathways are involved in this process.MSC-Shh also increases the levels of neurotrophic factors in the host retina and promoted RGCs survival in diabetic mice.展开更多
When better fuel-air mixing in the combustion chamber or a reduction in base drag are required in vehicles,rockets,and aeroplanes,the base pressure control is activated.Controlling the base pressure and drag is necess...When better fuel-air mixing in the combustion chamber or a reduction in base drag are required in vehicles,rockets,and aeroplanes,the base pressure control is activated.Controlling the base pressure and drag is necessary in both scenarios.In this work,semi-circular ribs with varying diameters(2,4,and 6 mm)positioned at six distinct positions(0.5D,1D,1.5D,2D,3D,and 4D)inside a square duct with a side of 15 mm are proposed as an efficient way to apply the passive control technique.In-depth research is done on optimising rib size for various rib sites.According to this study,the base pressure rises as rib height increases.Furthermore,the optimal location for the semi-circular ribs with a diameter of 2 mm is at 0.5D.The 1D location appears to be optimal for the 4 mm size as well.For the 6 mm size,however,the 4D position fills this function.展开更多
基金the Puncak RM for the project under the grant 6733204-13069 to carry out the experiments。
文摘Graphene nanoplatelets(GNPs)have attracted tremendous interest due to their unique properties and bonding capabilities.This study focuses on the effect of GNP dispersion on the mechanical,thermal,and morphological behavior of GNP/epoxy nanocomposites.This study aims to understand how the dispersion of GNPs affects the properties of epoxy nanocomposite and to identify the best dispersion approach for improving mechanical performance.A solvent mixing technique that includes mechanical stirring and ultrasonication was used for producing the nanocomposites.Fourier transform infrared spectroscopy was used to investigate the interaction between GNPs and the epoxy matrix.The measurements of density and moisture content were used to confirm that GNPs were successfully incorporated into the nanocomposite.The findings showed that GNPs are successfully dispersed in the epoxy matrix by combining mechanical stirring and ultrasonication in a single step,producing well-dispersed nanocomposites with improved mechanical properties.Particularly,the nanocomposites at a low GNP loading of 0.1 wt%,demonstrate superior mechanical strength,as shown by increased tensile properties,including improved Young's modulus(1.86 GPa),strength(57.31 MPa),and elongation at break(4.98).The nanocomposite with 0.25 wt%GNP loading performs better,according to the viscoelastic analysis and flexural properties(113.18 MPa).Except for the nanocomposite with a 0.5 wt%GNP loading,which has a higher thermal breakdown temperature,the thermal characteristics do not significantly alter.The effective dispersion of GNPs in the epoxy matrix and low agglomeration is confirmed by the morphological characterization.The findings help with filler selection and identifying the best dispersion approach,which improves mechanical performance.The effective integration of GNPs and their interaction with the epoxy matrix provides the doorway for additional investigation and the development of sophisticated nanocomposites.In fields like aerospace,automotive,and electronics where higher mechanical performance and functionality are required,GNPs'improved mechanical properties and successful dispersion present exciting potential.
基金funded by grants from the National Natural Science Foundation of China(grant numbers 82170912 and 82370910)the Beijing Stomatological Hospital,Capital Medical University Young Scientist Program(No.YSP202404).
文摘Periodontal disease is a risk factor for many systemic diseases such as Alzheimer’s disease and adverse pregnancy outcomes.Cleft palate(CP),the most common congenital craniofacial defect,has a multifaceted etiology influenced by complex genetic and environmental risk factors such as maternal bacterial or virus infection.A prior case-control study revealed a surprisingly strong association between maternal periodontal disease and CP in offspring.However,the precise relationship remains unclear.In this study,the relationship between maternal oral pathogen and CP in offspring was studied by sonicated P.gingivalis injected intravenously and orally into pregnant mice.We investigated an obvious increasing CP(12.5%)in sonicated P.gingivalis group which had inhibited osteogenesis in mesenchyme and blocked efferocytosis in epithelium.Then glycolysis and H4K12 lactylation(H4K12la)were detected to elevate in both mouse embryonic palatal mesenchyme(MEPM)cells and macrophages under P.gingivalis exposure which further promoted the transcription of metallopeptidase domain17(ADAM17),subsequently mediated the shedding of transforming growth factor-beta receptor 1(TGFBR1)in MEPM cells and mer tyrosine kinase(MerTK)in macrophages and resulted in the suppression of efferocytosis and osteogenesis in palate,eventually caused abnormalities in palate fusion and ossification.The abnormal efferocytosis also led to a predominance of M1 macrophages,which indirectly inhibited palatal osteogenesis via extracellular vesicles.Furthermore,pharmacological ADAM17 inhibition could ameliorate the abnormality of P.gingivalis-induced abnormal palate development.Therefore,our study extends the knowledge of how maternal oral pathogen affects fetal palate development and provides a novel perspective to understand the pathogenesis of CP.
基金supported by the National Natural Science Foundation of China,Nos.82171456(to QY)and 81971229(to QY)the Natural Science Foundation of Chongqing,Nos.CSTC2021JCYJ-MSXMX0263(to QY)and CSTB2023NSCQ-MSX1015(to XL)Doctoral Innovation Project of The First Affiliated Hospital of Chongqing Medical University,Nos.CYYY-BSYJSCXXM-202318(to JW)and CYYY-BSYJSCXXM-202327(to HT).
文摘Recent studies have shown that fibrotic scar formation following cerebral ischemic injury has varying effects depending on the microenvironment.However,little is known about how fibrosis is induced and regulated after cerebral ischemic injury.Sonic hedgehog signaling participates in fibrosis in the heart,liver,lung,and kidney.Whether Shh signaling modulates fibrotic scar formation after cerebral ischemic stroke and the underlying mechanisms are unclear.In this study,we found that Sonic Hedgehog expression was upregulated in patients with acute ischemic stroke and in a middle cerebral artery occlusion/reperfusion injury rat model.Both Sonic hedgehog and Mitofusin 2 showed increased expression in the middle cerebral artery occlusion rat model and in vitro fibrosis cell model induced by transforming growth factor-beta 1.Activation of the Sonic hedgehog signaling pathway enhanced the expression of phosphorylated Smad 3 and Mitofusin 2 proteins,promoted the formation of fibrotic scars,protected synapses or promoted synaptogenesis,alleviated neurological deficits following middle cerebral artery occlusion/reperfusion injury,reduced cell apoptosis,facilitated the transformation of meninges fibroblasts into myofibroblasts,and enhanced the proliferation and migration of meninges fibroblasts.The Smad3 phosphorylation inhibitor SIS3 reversed the effects induced by Sonic hedgehog signaling pathway activation.Bioinformatics analysis revealed significant correlations between Sonic hedgehog and Smad3,between Sonic hedgehog and Mitofusin 2,and between Smad3 and Mitofusin 2.These findings suggest that Sonic hedgehog signaling may influence Mitofusin 2 expression by regulating Smad3 phosphorylation,thereby modulating the formation of early fibrotic scars following cerebral ischemic stroke and affecting prognosis.The Sonic Hedgehog signaling pathway may serve as a new therapeutic target for stroke treatment.
文摘传统互联网为实现端到端安全、可靠、实时的网络业务保障,需要在网元节点部署多类组网服务。然而,现有大多数网络设备只提供网络接入和路由等服务功能,缺乏安全、可靠、实时的服务设计。基于开源网络操作系统(software for open networking in the cloud,SONiC)、容器技术和行为树设计一种组网服务管控架构及调度方法,实现面向网络业务保障的组网服务部署,将组网服务部署可编程网络设备进行统一管理和调度,并进行仿真测试。所述组网服务管控架构及调度方法进一步增强了网络设备能力,利用行为树高效协调管控调度过程中的状态转化,保障组网服务的交付质量。
文摘Striatal interneurons play a key role in modulating striatal-dependent behaviors,including motor activity and reward and emotional processing.Interneurons not only provide modulation to the basal ganglia circuitry under homeostasis but are also involved in changes to plasticity and adaptation during disease conditions such as Parkinson's or Huntington's disease.This review aims to summarize recent findings regarding the role of striatal cholinergic and GABAergic interneurons in providing circuit modulation to the basal ganglia in both homeostatic and disease conditions.In addition to direct circuit modulation,striatal interneurons have also been shown to provide trophic support to maintain neuron populations in adulthood.We discuss this interesting and novel role of striatal interneurons,with a focus on the maintenance of adult dopaminergic neurons from interneuronderived sonic-hedgehog.
文摘During the Indian National Gas Hydrate Program(NGHP)Expedition 02,Logging-while-drilling(LWD)logs were acquired at three sites(NGHP-02-11,NGHP-02-12,and NGHP-02-13)across the Mahanadi Basin in area A.We applied rock physics theory to available sonic velocity logs to know the distribution of gas hydrate at site NGHP-02-11 and NGHP-02-13.Rock physics modeling using sonic velocity at well location shows that gas hydrate is distributed mainly within the depth intervals of 150-265 m and 100 -215 mbsf at site NGHP-02-11 and NGHP-02-13,respectively,with an average saturation of about 4%of the pore space and the maximum concentration of about 40%of the pore space at 250 m depth at site NGHP-02-11,and at site NGHP-02-13 an average saturation of about 2%of the pore space and the maximum concentration of about 20%of the pore space at 246 m depth,as gas hydrate is distributed mainly within 100-246 mbsf at this site.Saturation of gas hydrate estimated from the electrical resistivity method using density derived porosity and electrical resistivity logs from Archie's empirical formula shows high saturation compared to that from the sonic log.However,estimates of hydrate saturation based on sonic P-wave velocity may differ significantly from that based on resistivity,because gas and hydrate have higher resistivity than conductive pore fluid and sonic P-wave velocity shows strong effect on gas hydrate as a small amount of gas reduces the velocity significantly while increasing velocity due to the presence of hydrate.At site NGHP-02-11,gas hydrate saturation is in the range of 15%e30%,in two zones between 150-180 and 245-265 mbsf.Site NGHP-02-012 shows a gas hydrate saturation of 20%e30%in the zone between 100 and 207 mbsf.Site NGHP-02-13 shows a gas hydrate saturation up to 30%in the zone between 215 and 246 mbsf.Combined observations from rock physics modeling and Archie’s approximation show the gas hydrate concentrations are relatively low(<4%of the pore space)at the sites of the Mahanadi Basin in the turbidite channel system.
基金supported by the National Natural Science Foundation of China (no.82072515)Guangdong Basic and Applied Basic Research Foundation (2023A1515220072,2021A1515220030)+1 种基金Shenzhen High-level Hospital Construction Fund (no.4001013)Shenzhen Science and Technology Projects (no.JCYJ20220530150615035)。
文摘Background:The biomechanical environment created by suture-button fixation Latarjet is conducive to the healing and shaping of the transplanted coracoid,but its mechanism remains unclear.The latest research has found that the absence of stem cell chemokine(CXCL12)impeded bone regeneration in Sonic Hedgehog(SHH)-deficient animals.However,whether the biomechanical environment affects SHH and CXCL12 function has not been studied.Methods:Rat fracture models were constructed to simulate stress environments under non-l oad-bearing and load-bearing conditions.The fracture healing and shaping,as well as the expression levels of SHH and CXCL12,were assessed through gross viewing,micro-computed tomography(micro-CT),and histochemical staining.Results:Under flexible fixation,the relative bone volume(BV/TV)of rats exposed to the load-bearing stress environment was significantly higher than that of rats under a non-l oad-bearing stress environment(p≤0.05).Adverse bone shaping was not observed in rats subjected to flexible fixation.The levels of SHH and CXCL12in load-bearing rats exhibited significant elevation(p≤0.05).Under a load-bearing stress environment,no significant difference was observed in the BV/TV between the flexible fixation group and the rigid fixation group(p≥0.05),but there was excessive hyperplasia of the fracture callus in the rigid fixation group.The levels of SHH and CXCL12 in rats subjected to rigid fixation were significantly elevated(p≤0.05).Conclusions:Flexible fixation and load-bearing stress environment may contribute to bone healing and shaping by influencing the levels of SHH and CXCL12,suggested that this mechanism may be relevant to the healing and shaping of the transplanted coracoid after suture-button fixation Latarjet.
基金supported by Major Science and Technology Special Project of China National Petroleum Corporation"Research on Large scale Storage and Production Increase and Exploration and Development Technology of Continental Shale Oil"(2023ZZ15)。
文摘Qingshankou shale(Gulong area,China)exhibits strong acoustic anisotropy characteristics,posing significant challenges to its exploration and development.In this study,the five full elastic constants and multipole response law of the Qingshankou shale were studied using experimental measurements.Analyses show that the anisotropy parametersϵandγin the study region are greater than 0.4,whereas the anisotropy parameterδis smaller,generally 0.1.Numerical simulations show that the longitudinal and transverse wave velocities of these strong anisotropic rocks vary significantly with inclination angle,and significant differences in group velocity and phase velocity are also present.Acoustic logging measures the group velocity in dipped boreholes;this differs from the phase velocity to some extent.As the dip angle increases,the longitudinal and SH wave velocities increase accordingly,while the qSV-wave velocity initially increases and then decreases,reaching its maximum value at a dip of approximately 40°.These results provide an effective guide for the correction and modeling of acoustic logging time differences in the region.
基金Supported by the Natural Science Foundation of Guangdong Province(No.2018A0303130293,No.2023A1515012470).
文摘AIM:To investigate the effects of Sonic hedgehog(Shh)gene-modified bone marrow mesenchymal stem cells(MSCs)on graft-induced retinal gliosis and retinal ganglion cells(RGCs)survival in diabetic mice.METHODS:Bone marrow-derived MSCs were genetically modified with the Shh gene to generate a stably transfected cell line of Shh-modified MSCs(MSC-Shh).Intravitreal injections of MSC-Shh and green fluorescent protein-modified MSCs(MSC-Gfp;control)were administered in diabetic mice.After 4wk,the effects of MSC-Shh on retinal gliosis were evaluated using fundus photography,and markers of gliosis were examined by immunofluorescence and Western blotting.The neurotrophic factors expression and RGCs survival in the host retina were evaluated using Western blotting and immunofluorescence.The mechanisms underlying the effects of MSC-Shh was investigated.RESULTS:A significant reduction of proliferative vitreoretinopathy(PVR)was observed after intravitreal injection of MSC-Shh compared to MSC-Gfp.Significant downregulation of glial fibrillary acidic protein(GFAP)was demonstrated in the host retina after MSC-Shh administration compared to MSC-Gfp.The extracellular signal-regulated kinase 1/2(ERK1/2),protein kinase B(AKT)and phosphatidylin-ositol-3-kinase(PI3K)pathways were significantly downregulated after MSC-Shh administration compared to MSC-Gfp.Brain-derived neurotrophic factor(BDNF)and ciliary neurotrophic factor(CNTF)levels were significantly increased in the host retina,and RGCs loss was significantly prevented after MSC-Shh administration.CONCLUSION:MSC-Shh administration reduces graft-induced reactive gliosis following intravitreal injection in diabetic mice.The ERK1/2,AKT and PI3K pathways are involved in this process.MSC-Shh also increases the levels of neurotrophic factors in the host retina and promoted RGCs survival in diabetic mice.
基金supported by the Structures and Materials(S&M)Research Lab of Prince Sultan Universitysupport of Prince Sultan University in paying the article processing charges(APC)for this publication.
文摘When better fuel-air mixing in the combustion chamber or a reduction in base drag are required in vehicles,rockets,and aeroplanes,the base pressure control is activated.Controlling the base pressure and drag is necessary in both scenarios.In this work,semi-circular ribs with varying diameters(2,4,and 6 mm)positioned at six distinct positions(0.5D,1D,1.5D,2D,3D,and 4D)inside a square duct with a side of 15 mm are proposed as an efficient way to apply the passive control technique.In-depth research is done on optimising rib size for various rib sites.According to this study,the base pressure rises as rib height increases.Furthermore,the optimal location for the semi-circular ribs with a diameter of 2 mm is at 0.5D.The 1D location appears to be optimal for the 4 mm size as well.For the 6 mm size,however,the 4D position fills this function.
