Compared to existing deformation monitoring methods,landslide early warning can be achieved by detecting precursor signals of slope instability through acoustic emission(AE).Acquisition of AE signals generated by acti...Compared to existing deformation monitoring methods,landslide early warning can be achieved by detecting precursor signals of slope instability through acoustic emission(AE).Acquisition of AE signals generated by active waveguide facilitates monitoring the development of shear surface and provides a foundation for quantifying landslide movement.Backfill particles are the dominant AE sources in active waveguides,typically chosen from materials such as gravels or sands.However,the influence of particle sizes and gradings has not been clarified in existing laboratory models or field monitoring.This research introduces a direct shear test for active waveguide,where spherical glass beads are employed to precisely regulate the size and grading of backfill particles.A programmable logic controller maintains a constant shearing speed and equivalent total deformation.Through a comprehensive analysis of AE,deformation,and mechanical measurements,this study evaluates the impact of particle size and grading on monitoring capabilities.The findings suggest that the AE mechanism in glass beads is attributed to particle collision and dislocation,leading to AE events characterized by low amplitude and energy levels.The percentage of high-amplitude AE events rises steadily with the progression of shearing.The correlation between shear force,cumulative ring down count(RDC)of AE,and deformation conforms to a power function,with the exponent relying on particle size,grading,and shearing speed.Notably,the combination of small particles and low shearing speeds can yield the maximum cumulative RDC,while selecting particles with uneven grading will significantly enhance the intensity of AE signals from active waveguide.展开更多
The present study aimed to examine the effectiveness of bi-level positive airway pressure(BiPAP)versus continuous positive airway pressure(CPAP)in preterm infants with birth weight less than 1500 g and respiratory dis...The present study aimed to examine the effectiveness of bi-level positive airway pressure(BiPAP)versus continuous positive airway pressure(CPAP)in preterm infants with birth weight less than 1500 g and respiratory distress syndrome(RDS)following intubation-surfactant-extubation(INSURE)treatment.A two-center randomized control trial was performed.The primary outcome was the reintubation rate of infants within 72 h of age after INSURE.Secondary outcomes included bronchopulmonary dysplasia(BPD),necrotizing enterocolitis(NEC),retinopathy of prematurity(ROP)and incidences of adverse events.Lung function at one year of corrected age was also compared between the two groups.There were 140 cases in the CPAP group and 144 in the BiPAP group.After INSURE,the reintubation rates of infants within 72 h of age were 15%and 11.1%in the CPAP group and the BiPAP group,respectively(P>0.05).Neonates in the BiPAP group was on positive airway pressure(PAP)therapy three days less than in the CPAP group(12.6 d and 15.3 d,respectively,P<0.05),and on oxygen six days less than in the CPAP group(20.6 d and 26.9 d,respectively,P<0.05).Other outcomes such as BPD,NEC,ROP and feeding intolerance were not significantly different between the two groups(P>0.05).There was no difference in lung function at one year of age between the two groups(P>0.05).In conclusion,after INSURE,the reintubation rate of infants within 72 h of age was comparable between the BiPAP group and the CPAP group.BiPAP was superior to CPAP in terms of shorter durations(days)on PAP support and oxygen supplementation.There were no differences in the incidences of BPD and ROP,and lung function at one year of age between the two ventilation methods.展开更多
Curcumin improves the learning and memory deficits in rats induced by the gp120 V3 loop. The present study cultured rat hippocampal neurons with 1 nM gp120 V3 loop and 1 μM curcumin for 24 hours. The results showed t...Curcumin improves the learning and memory deficits in rats induced by the gp120 V3 loop. The present study cultured rat hippocampal neurons with 1 nM gp120 V3 loop and 1 μM curcumin for 24 hours. The results showed that curcumin inhibited the gp120 V3 loop-induced mitochondrial membrane potential decrease, reduced the mRNA expression of the pro-apoptotic gene caspase-3, and attenuated hippocampal neuronal injury.展开更多
Five new species(Gastrochilus yei,Gastrochilus minimus,Luisia simaoensis,Taeniophyllum xizangense,Tuberolabium subulatum)and two newly recorded species(Cleisostoma tricornutum,Luisia inconspicua)of Vandeae(Orchidaceae...Five new species(Gastrochilus yei,Gastrochilus minimus,Luisia simaoensis,Taeniophyllum xizangense,Tuberolabium subulatum)and two newly recorded species(Cleisostoma tricornutum,Luisia inconspicua)of Vandeae(Orchidaceae)from China are described and illustrated.Gastrochilus yei is similar to G.affinis and G.nepalensis,but differs from them by having an epichile not lobed,the apex of the hypochile not bilobed,and a tine on the apex of the leaf.Gastrochilus minimus is similar to G.acinacifolius,but can be distinguished from the latter by having a flabellate epichile that is densely hirsute on the adaxial surface and an inconspicuous central cushion;in addition,the hypochile of G.minimus has a keel that extends to the apex of the epichile.Taeniophyllum xizangense is similar to T.stella and T.radiatum,but it is distinguished from them by having much bigger flowers,inflorescences densely covered with short-bristly hairs,papillae on the external surface of sepals,and bigger triangular-ovate viscidium.Luisia simaoensis is similar to L magniflora and L ramosii,but can be easily distinguished from them by having lateral sepals longer than dorsal sepals and petals,lip with irregular and waved margins,and lip with bilobed apex.Luisia inconspicua is moved from Gastrochilus to Luisia based on phylogenetic analyses of plastid matK sequence data.Tuberolabium subulatum is similar to T.camosum,but it can be easily distinguished from the latter by having an inflorescence much shorter than the leaves,yellow sepals and petals,and many small papillae outside the lip lobes.展开更多
基金funding support from the National Natural Science Foundation of China(Grant No.52404224)Beijing Natural Science Foundation(Grant No.8244051)the fellowship of China National Postdoctoral Program for Innovative Talents(Grant No.BX20230175).
文摘Compared to existing deformation monitoring methods,landslide early warning can be achieved by detecting precursor signals of slope instability through acoustic emission(AE).Acquisition of AE signals generated by active waveguide facilitates monitoring the development of shear surface and provides a foundation for quantifying landslide movement.Backfill particles are the dominant AE sources in active waveguides,typically chosen from materials such as gravels or sands.However,the influence of particle sizes and gradings has not been clarified in existing laboratory models or field monitoring.This research introduces a direct shear test for active waveguide,where spherical glass beads are employed to precisely regulate the size and grading of backfill particles.A programmable logic controller maintains a constant shearing speed and equivalent total deformation.Through a comprehensive analysis of AE,deformation,and mechanical measurements,this study evaluates the impact of particle size and grading on monitoring capabilities.The findings suggest that the AE mechanism in glass beads is attributed to particle collision and dislocation,leading to AE events characterized by low amplitude and energy levels.The percentage of high-amplitude AE events rises steadily with the progression of shearing.The correlation between shear force,cumulative ring down count(RDC)of AE,and deformation conforms to a power function,with the exponent relying on particle size,grading,and shearing speed.Notably,the combination of small particles and low shearing speeds can yield the maximum cumulative RDC,while selecting particles with uneven grading will significantly enhance the intensity of AE signals from active waveguide.
文摘The present study aimed to examine the effectiveness of bi-level positive airway pressure(BiPAP)versus continuous positive airway pressure(CPAP)in preterm infants with birth weight less than 1500 g and respiratory distress syndrome(RDS)following intubation-surfactant-extubation(INSURE)treatment.A two-center randomized control trial was performed.The primary outcome was the reintubation rate of infants within 72 h of age after INSURE.Secondary outcomes included bronchopulmonary dysplasia(BPD),necrotizing enterocolitis(NEC),retinopathy of prematurity(ROP)and incidences of adverse events.Lung function at one year of corrected age was also compared between the two groups.There were 140 cases in the CPAP group and 144 in the BiPAP group.After INSURE,the reintubation rates of infants within 72 h of age were 15%and 11.1%in the CPAP group and the BiPAP group,respectively(P>0.05).Neonates in the BiPAP group was on positive airway pressure(PAP)therapy three days less than in the CPAP group(12.6 d and 15.3 d,respectively,P<0.05),and on oxygen six days less than in the CPAP group(20.6 d and 26.9 d,respectively,P<0.05).Other outcomes such as BPD,NEC,ROP and feeding intolerance were not significantly different between the two groups(P>0.05).There was no difference in lung function at one year of age between the two groups(P>0.05).In conclusion,after INSURE,the reintubation rate of infants within 72 h of age was comparable between the BiPAP group and the CPAP group.BiPAP was superior to CPAP in terms of shorter durations(days)on PAP support and oxygen supplementation.There were no differences in the incidences of BPD and ROP,and lung function at one year of age between the two ventilation methods.
基金supported by the Natural Science Foundation of Guangdong Province, No. 9151040701000, 061050246the Science and Technology Project of Guangdong Province, No. 2010B030700016+1 种基金the Science and Technology Project of Guangzhou, No. 2010Y1-C291the National Natural Science Foundation of China, No. 81171134
文摘Curcumin improves the learning and memory deficits in rats induced by the gp120 V3 loop. The present study cultured rat hippocampal neurons with 1 nM gp120 V3 loop and 1 μM curcumin for 24 hours. The results showed that curcumin inhibited the gp120 V3 loop-induced mitochondrial membrane potential decrease, reduced the mRNA expression of the pro-apoptotic gene caspase-3, and attenuated hippocampal neuronal injury.
基金supported by Grant from National Forestry and Grassland Administration(No.2019073018,2019073019,2019073002,2019073003)Science and Technology Basic Resources Investigation Program of China"Survey and Germplasm Conservation of Plant Species with Extremely Small Populations in South-west China"(Grant No.2017FY100100)+3 种基金National Natural Science Foundation of China(No.31870195)Strategic Biological Resources Capacity Building Project from the Chinese Academy of Sciences"Seed Plants Research in Xishuangbanna Karst Region"(Grant No.KFJ-BRP-017-36)the Large-scale Scientific Facilities of the Chinese Academy of Sciences(Grant No.2017-LSFGBOWS-02)the National Wild Plant Germplasm Resource Center,National Science&Technology Infrastructure。
文摘Five new species(Gastrochilus yei,Gastrochilus minimus,Luisia simaoensis,Taeniophyllum xizangense,Tuberolabium subulatum)and two newly recorded species(Cleisostoma tricornutum,Luisia inconspicua)of Vandeae(Orchidaceae)from China are described and illustrated.Gastrochilus yei is similar to G.affinis and G.nepalensis,but differs from them by having an epichile not lobed,the apex of the hypochile not bilobed,and a tine on the apex of the leaf.Gastrochilus minimus is similar to G.acinacifolius,but can be distinguished from the latter by having a flabellate epichile that is densely hirsute on the adaxial surface and an inconspicuous central cushion;in addition,the hypochile of G.minimus has a keel that extends to the apex of the epichile.Taeniophyllum xizangense is similar to T.stella and T.radiatum,but it is distinguished from them by having much bigger flowers,inflorescences densely covered with short-bristly hairs,papillae on the external surface of sepals,and bigger triangular-ovate viscidium.Luisia simaoensis is similar to L magniflora and L ramosii,but can be easily distinguished from them by having lateral sepals longer than dorsal sepals and petals,lip with irregular and waved margins,and lip with bilobed apex.Luisia inconspicua is moved from Gastrochilus to Luisia based on phylogenetic analyses of plastid matK sequence data.Tuberolabium subulatum is similar to T.camosum,but it can be easily distinguished from the latter by having an inflorescence much shorter than the leaves,yellow sepals and petals,and many small papillae outside the lip lobes.