To address the problem of poor wave resistance of existing offshore floating wind turbines,a new type of semisubmersible platform with truncated-cone-type upper pontoons is proposed by combining the characteristics of...To address the problem of poor wave resistance of existing offshore floating wind turbines,a new type of semisubmersible platform with truncated-cone-type upper pontoons is proposed by combining the characteristics of offshore wind turbine semi-submersible floating platforms.Based on the coupled hydrodynamic,aerodynamic,and mooring force physical fields of FAST,the surge,heave,pitch,and yaw motions responses of the floating wind turbine under different wave heights and periods are obtained,and the mooring line tension responses are also obtained;and compare the dynamic response of the new semi-submersible platform with the OC4-DeepCwind platformat six degrees of freedom.The results show that different wave conditions have obvious effects on the heave and pitch motions of the new floating wind turbine,and fewer effects on the surge and yaw motions;the tensegrity response of the mooring system is more affected by the wave conditions;compared with the OC4-DeepCwind floating wind turbine,the pitch and roll response of the new floating wind turbine has been significantly reduced and has good stability.展开更多
Background Laparoscopic surgery in pregnant women has become increasingly more common; however, the safety of laparoscopy in this population has been widely debated in emergent situations and big size at bigger pregna...Background Laparoscopic surgery in pregnant women has become increasingly more common; however, the safety of laparoscopy in this population has been widely debated in emergent situations and big size at bigger pregnant weeks. This study was to determine the characteristics of laparoscopic surgery for adnexal masses in different conditions during the second trimester of pregnancy. Methods Between April 2002 and December 2011, 24 patients with suspected ovary cyst during the second trimester underwent laparoscopic surgery at the Peking Union Medical College Hospital retrospectively. Clinical data were collected retrospectively and patient's outcomes were analyzed. Results The incidence of laparoscopic surgery for ovarian cysts during pregnancy was 0.12% of all laparoscopic gynecological surgeries performed at the hospital. No patients required conversion. There were 9 (37.5%) patients whose gestational age was no less than 16 weeks, and 15 patients whose gestational age was less than 16 weeks; no difference was noted in the operation time between the two groups (P 〉0.05). Emergency surgery due to abdominal pain was performed in 4 (16.7%) patients, 2 (8.3%) of whom underwent simple salpingo-oophorectomy because of ovarian necrosis. The other patients underwent enucleation of the ovarian cyst. There were no severe complications. Twenty (83.3%) pregnant women delivered healthy term infants and 4 (16.7%) cases were lost to follow up. Conclusion Laparoscopic surgery for ovary masses is a safe and feasible procedure for the treatment of ovary cyst in dif- ferent conditions during the second trimester, even if gestational age reaching 16-19 weeks or in emergency.展开更多
The microRaman scattering of 4H-SiC films, fabricated by low pressure chemical vapor deposition under different growth conditions, is investigated at temperatures ranging from 80 K to 550K. The effects of growth condi...The microRaman scattering of 4H-SiC films, fabricated by low pressure chemical vapor deposition under different growth conditions, is investigated at temperatures ranging from 80 K to 550K. The effects of growth conditions on E2 (TO), E1 (TO) and A1 (LO) phonon mode frequencies are negligible. The temperature dependences of phonon linewidth and lifetime of E2 (TO) modes are analyzed in terms of an anharmonic damping effect induced by thermal and growth conditions. The results show that the lifetime of E2 (TO) mode increases when the quality of the sample improves. Unlike other phone modes, Raman shift of A1 (longitudinal optical plasma coupling (LOPC)) mode does not decrease monotonously when the temperature increases, but tends to blueshift at low temperatures and to redshift at relatively high temperatures. Theoretical analyses are given for the abnormal phenomena of A1 (LOPC) mode in 4H-SiC.展开更多
Real-time quantitative PCR(qPCR)is a reliable and widely used technique for analyzing the expression profiles of target genes in different species,and reference genes with stable expressions have been introduced for t...Real-time quantitative PCR(qPCR)is a reliable and widely used technique for analyzing the expression profiles of target genes in different species,and reference genes with stable expressions have been introduced for the normalization of the data.Therefore,stability evaluation should be considered as the initial step for qPCR experiments.The fall armyworm Spodoptera frugiperda(J.E.Smith)(Lepidoptera:Noctuidae)is a polyphagous pest that consumes many plant species and seriously threatens corn production around the world.However,no studies thus far have examined the stability of reference genes in this pest.In this study,the expression profiles of the eight candidate reference genes of Actin,elongation factor 1 alpha(EF1α),elongation factor 2(EF2),glyceraldehyde-3-phosphate dehydrogenase(GAPDH),ribosomal protein L3(RPL3),ribosomal protein L13(RPL13),alpha-tubulin(α-TUB),and beta-1-tubulin(β-1-TUB)were obtained from S.frugiperda in different samples and the stability was evaluated byΔCt,BestKeeper,geNorm,NormFinder,and RefFinder methods.The results of pairwise variation(V)calculated by GeNorm indicated two reference genes could be selected for normalization.Therefore,the combinations of the most stable reference genes for different experimental conditions of S.frugiperda were shown as follows:EF2 and RPL13 for developmental stages,RPL3 andβ-1-TUB for larval tissue samples,EF2 and EF1αfor the larval samples treated with different temperatures,RPL3 and EF1αfor the larval samples under starvation stress,and RPL13 and EF1αfor all the samples.Our results lay the foundation for the normalization of qPCR analyses in S.frugiperda and could help guarantee the accuracy of subsequent research.展开更多
In different synoptic conditions and at different time scales,the analysis of the energy budgets by Bowen Ratio Method and Bulk Schemes over Huaihe River Basin during the field observation periods of HUBEX in 1999 sho...In different synoptic conditions and at different time scales,the analysis of the energy budgets by Bowen Ratio Method and Bulk Schemes over Huaihe River Basin during the field observation periods of HUBEX in 1999 shows that,(1)the averaged latent heat flux is an order of magnitude more than the averaged sensible heat flux during the observation period:(2)the variation of total cloud amount is out of phase with the terms of energy budgets except for the downward longwave radiation which maybe is related to the cloud's height and class:(3)the values of sensible and latent heat fluxes are small during rain episodes,but thereafter,the values become high and then up to maximum.It is similar to the other terms of the energy budgets except for the downward longwave radiation.The diurnal variation of energy budgets indicates that the daytime precipitation exerts great influence to the energy budgets,but the nighttime precipitation makes little influence; (4)the variation of the latent heat flux is in phase with the evaporation,which indicates that the latent heat flux calculated by bulk schemes is reliable:(5)the means of the sensible and latent heat flux and momentum flux by bulk schemes for the time period from May to August are, respectively,30.71W/m^2.116.81W/m^2.2.86×10^(-2)N/m^2 in 1998 and 30.28W/m^2,107.35 W/m^2,2.74×10^(-2)N/m^2 in 1999.The values of these two years are similar.During summer in 1999 the magnitude and activity of sensible heat flux are strongest in June and those of the latent heat flux are in August.展开更多
We have simulated the processes of transient reconnection at the nightside magnetopause by using a two-dimensional compressible MHD model.According to the simulation results,three types of global reconnection configur...We have simulated the processes of transient reconnection at the nightside magnetopause by using a two-dimensional compressible MHD model.According to the simulation results,three types of global reconnection configuration at the magnetopause are proposed.The main results are summarized as follows.展开更多
Internal thermal insulation composite system(ITICS)can be an important measure for the energy-saving retrofitting of buildings.However,ITICS may cause harmful effects on the hygrothermal performance of building envelo...Internal thermal insulation composite system(ITICS)can be an important measure for the energy-saving retrofitting of buildings.However,ITICS may cause harmful effects on the hygrothermal performance of building envelopes.This work investigated the influence of the materials’hygric properties on the hygrothermal perfor-mance of a typical ITICS in different climate conditions in China.Two base wall materials,the traditional concrete and a new type aerated concrete,were tested and compared for their hygric properties firstly.The influence of the hygroscopicity of exterior plasters,the permeability of insulation materials and the climate conditions were then analyzed with WUFI simulations.The hygrothermal performance was evaluated with consideration of the total water content(TWC)of the walls and the moisture flux strength,the relative humidity(RH)and the mould growth risk at the interface between the base wall and the insulation layer(B-I interface).The numerical analysis implies that the TWC of internal insulated walls depends mainly on the hygroscopicity of exterior plaster and the wind-driven rain intensity.The upper limits for the water absorption coefficient of exterior plasters used in Bei-jing,Shanghai and Fuzhou are 1e-9,1e-10,1e-10 m^(2)/s respectively.When such limits are guaranteed,a vapour tight system created by using insulation materials with a large vapour resistance factor or adding a vapour barrier can improve the hygrothermal performance of ITICS,especially for concrete walls in cold climate.展开更多
Bone tissue engineering has emerged as a significant research area that provides promising novel tools for the preparation of biomimetic hydrogels applied in bone-related diseases(e.g.,bone defects,cartilage damage,os...Bone tissue engineering has emerged as a significant research area that provides promising novel tools for the preparation of biomimetic hydrogels applied in bone-related diseases(e.g.,bone defects,cartilage damage,osteoarthritis,etc.).Herein,thermal sensitive polymers(e.g.,PNIPAAm,Soluplus,etc.)were introduced into main chains to fabricate biomimetic hydrogels with injectability and compatibility for those bone defect need minimally invasive surgery.Mineral ions(e.g.,calcium,copper,zinc,and magnesium),as an indispensable role in maintaining the balance of the organism,were linked with polymer chains to form functional hydrogels for accelerating bone regeneration.In the chemically triggered hydrogel section,advanced hydrogels crosslinked by different molecular agents(e.g.,genipin,dopamine,caffeic acid,and tannic acid)possess many advantages,including extensive selectivity,rapid gel-forming capacity and tunable mechanical property.Additionally,photo crosslinking hydrogel with rapid response and mild condition can be triggered by different photoinitiators(e.g.,I2959,LAP,eosin Y,riboflavin,etc.)under specific wavelength of light.Moreover,enzyme triggered hydrogels were also utilized in the tissue regeneration due to its rapid gel-forming capacity and excellent biocompatibility.Particularly,some key factors that can determine the therapy effect for bone tissue engineering were also mentioned.Finally,brief summaries and remaining issues on how to properly design clinical-oriented hydrogels were provided in this review.展开更多
基金funded by the National Key R&D Program of China(Grant Number 2018YFB1501203)funded by the National Natural Science Foundation of China(Grant Number 52075305).
文摘To address the problem of poor wave resistance of existing offshore floating wind turbines,a new type of semisubmersible platform with truncated-cone-type upper pontoons is proposed by combining the characteristics of offshore wind turbine semi-submersible floating platforms.Based on the coupled hydrodynamic,aerodynamic,and mooring force physical fields of FAST,the surge,heave,pitch,and yaw motions responses of the floating wind turbine under different wave heights and periods are obtained,and the mooring line tension responses are also obtained;and compare the dynamic response of the new semi-submersible platform with the OC4-DeepCwind platformat six degrees of freedom.The results show that different wave conditions have obvious effects on the heave and pitch motions of the new floating wind turbine,and fewer effects on the surge and yaw motions;the tensegrity response of the mooring system is more affected by the wave conditions;compared with the OC4-DeepCwind floating wind turbine,the pitch and roll response of the new floating wind turbine has been significantly reduced and has good stability.
文摘Background Laparoscopic surgery in pregnant women has become increasingly more common; however, the safety of laparoscopy in this population has been widely debated in emergent situations and big size at bigger pregnant weeks. This study was to determine the characteristics of laparoscopic surgery for adnexal masses in different conditions during the second trimester of pregnancy. Methods Between April 2002 and December 2011, 24 patients with suspected ovary cyst during the second trimester underwent laparoscopic surgery at the Peking Union Medical College Hospital retrospectively. Clinical data were collected retrospectively and patient's outcomes were analyzed. Results The incidence of laparoscopic surgery for ovarian cysts during pregnancy was 0.12% of all laparoscopic gynecological surgeries performed at the hospital. No patients required conversion. There were 9 (37.5%) patients whose gestational age was no less than 16 weeks, and 15 patients whose gestational age was less than 16 weeks; no difference was noted in the operation time between the two groups (P 〉0.05). Emergency surgery due to abdominal pain was performed in 4 (16.7%) patients, 2 (8.3%) of whom underwent simple salpingo-oophorectomy because of ovarian necrosis. The other patients underwent enucleation of the ovarian cyst. There were no severe complications. Twenty (83.3%) pregnant women delivered healthy term infants and 4 (16.7%) cases were lost to follow up. Conclusion Laparoscopic surgery for ovary masses is a safe and feasible procedure for the treatment of ovary cyst in dif- ferent conditions during the second trimester, even if gestational age reaching 16-19 weeks or in emergency.
基金Supported by the National Natural Science Foundation of China under Grant Nos 61176085,11474365 and 61377055the Department of Education of Guangdong Province under Grant No gjhz1103the Open-Project Program of the State Key laboratory of Opto-Electronic Material and Technologies of Sun Yatsen University
文摘The microRaman scattering of 4H-SiC films, fabricated by low pressure chemical vapor deposition under different growth conditions, is investigated at temperatures ranging from 80 K to 550K. The effects of growth conditions on E2 (TO), E1 (TO) and A1 (LO) phonon mode frequencies are negligible. The temperature dependences of phonon linewidth and lifetime of E2 (TO) modes are analyzed in terms of an anharmonic damping effect induced by thermal and growth conditions. The results show that the lifetime of E2 (TO) mode increases when the quality of the sample improves. Unlike other phone modes, Raman shift of A1 (longitudinal optical plasma coupling (LOPC)) mode does not decrease monotonously when the temperature increases, but tends to blueshift at low temperatures and to redshift at relatively high temperatures. Theoretical analyses are given for the abnormal phenomena of A1 (LOPC) mode in 4H-SiC.
基金financially supported by the fund from the KeyArea Research and Development Program of Guangdong Province,China(2020B020223004)the Innovation Team Project in Guangdong Provincial Department of Education(2017KCXTD018)the Guangzhou Science and Technology Plan Projects,China(201704020190,201805010008 and 201904010135)。
文摘Real-time quantitative PCR(qPCR)is a reliable and widely used technique for analyzing the expression profiles of target genes in different species,and reference genes with stable expressions have been introduced for the normalization of the data.Therefore,stability evaluation should be considered as the initial step for qPCR experiments.The fall armyworm Spodoptera frugiperda(J.E.Smith)(Lepidoptera:Noctuidae)is a polyphagous pest that consumes many plant species and seriously threatens corn production around the world.However,no studies thus far have examined the stability of reference genes in this pest.In this study,the expression profiles of the eight candidate reference genes of Actin,elongation factor 1 alpha(EF1α),elongation factor 2(EF2),glyceraldehyde-3-phosphate dehydrogenase(GAPDH),ribosomal protein L3(RPL3),ribosomal protein L13(RPL13),alpha-tubulin(α-TUB),and beta-1-tubulin(β-1-TUB)were obtained from S.frugiperda in different samples and the stability was evaluated byΔCt,BestKeeper,geNorm,NormFinder,and RefFinder methods.The results of pairwise variation(V)calculated by GeNorm indicated two reference genes could be selected for normalization.Therefore,the combinations of the most stable reference genes for different experimental conditions of S.frugiperda were shown as follows:EF2 and RPL13 for developmental stages,RPL3 andβ-1-TUB for larval tissue samples,EF2 and EF1αfor the larval samples treated with different temperatures,RPL3 and EF1αfor the larval samples under starvation stress,and RPL13 and EF1αfor all the samples.Our results lay the foundation for the normalization of qPCR analyses in S.frugiperda and could help guarantee the accuracy of subsequent research.
基金the National Natural Science Foundation of China(No.49794030).
文摘In different synoptic conditions and at different time scales,the analysis of the energy budgets by Bowen Ratio Method and Bulk Schemes over Huaihe River Basin during the field observation periods of HUBEX in 1999 shows that,(1)the averaged latent heat flux is an order of magnitude more than the averaged sensible heat flux during the observation period:(2)the variation of total cloud amount is out of phase with the terms of energy budgets except for the downward longwave radiation which maybe is related to the cloud's height and class:(3)the values of sensible and latent heat fluxes are small during rain episodes,but thereafter,the values become high and then up to maximum.It is similar to the other terms of the energy budgets except for the downward longwave radiation.The diurnal variation of energy budgets indicates that the daytime precipitation exerts great influence to the energy budgets,but the nighttime precipitation makes little influence; (4)the variation of the latent heat flux is in phase with the evaporation,which indicates that the latent heat flux calculated by bulk schemes is reliable:(5)the means of the sensible and latent heat flux and momentum flux by bulk schemes for the time period from May to August are, respectively,30.71W/m^2.116.81W/m^2.2.86×10^(-2)N/m^2 in 1998 and 30.28W/m^2,107.35 W/m^2,2.74×10^(-2)N/m^2 in 1999.The values of these two years are similar.During summer in 1999 the magnitude and activity of sensible heat flux are strongest in June and those of the latent heat flux are in August.
文摘We have simulated the processes of transient reconnection at the nightside magnetopause by using a two-dimensional compressible MHD model.According to the simulation results,three types of global reconnection configuration at the magnetopause are proposed.The main results are summarized as follows.
基金This research was funded by National Key R&D Program of China(2017YFC0702800),which is gratefully acknowledged.
文摘Internal thermal insulation composite system(ITICS)can be an important measure for the energy-saving retrofitting of buildings.However,ITICS may cause harmful effects on the hygrothermal performance of building envelopes.This work investigated the influence of the materials’hygric properties on the hygrothermal perfor-mance of a typical ITICS in different climate conditions in China.Two base wall materials,the traditional concrete and a new type aerated concrete,were tested and compared for their hygric properties firstly.The influence of the hygroscopicity of exterior plasters,the permeability of insulation materials and the climate conditions were then analyzed with WUFI simulations.The hygrothermal performance was evaluated with consideration of the total water content(TWC)of the walls and the moisture flux strength,the relative humidity(RH)and the mould growth risk at the interface between the base wall and the insulation layer(B-I interface).The numerical analysis implies that the TWC of internal insulated walls depends mainly on the hygroscopicity of exterior plaster and the wind-driven rain intensity.The upper limits for the water absorption coefficient of exterior plasters used in Bei-jing,Shanghai and Fuzhou are 1e-9,1e-10,1e-10 m^(2)/s respectively.When such limits are guaranteed,a vapour tight system created by using insulation materials with a large vapour resistance factor or adding a vapour barrier can improve the hygrothermal performance of ITICS,especially for concrete walls in cold climate.
基金the financial support from National Key R&D Program of China(2018YFC2001500)National Natural Science Foundation of China(91749204,82172098,81771491,81871099,81972254)Shanghai Rising-Star Program(21QA1412000).
文摘Bone tissue engineering has emerged as a significant research area that provides promising novel tools for the preparation of biomimetic hydrogels applied in bone-related diseases(e.g.,bone defects,cartilage damage,osteoarthritis,etc.).Herein,thermal sensitive polymers(e.g.,PNIPAAm,Soluplus,etc.)were introduced into main chains to fabricate biomimetic hydrogels with injectability and compatibility for those bone defect need minimally invasive surgery.Mineral ions(e.g.,calcium,copper,zinc,and magnesium),as an indispensable role in maintaining the balance of the organism,were linked with polymer chains to form functional hydrogels for accelerating bone regeneration.In the chemically triggered hydrogel section,advanced hydrogels crosslinked by different molecular agents(e.g.,genipin,dopamine,caffeic acid,and tannic acid)possess many advantages,including extensive selectivity,rapid gel-forming capacity and tunable mechanical property.Additionally,photo crosslinking hydrogel with rapid response and mild condition can be triggered by different photoinitiators(e.g.,I2959,LAP,eosin Y,riboflavin,etc.)under specific wavelength of light.Moreover,enzyme triggered hydrogels were also utilized in the tissue regeneration due to its rapid gel-forming capacity and excellent biocompatibility.Particularly,some key factors that can determine the therapy effect for bone tissue engineering were also mentioned.Finally,brief summaries and remaining issues on how to properly design clinical-oriented hydrogels were provided in this review.