In light of carbon-neutral pledge, the oil and gas industry has been facing several critical new challenges in China. The current status and new challenges in terms of market mechanism reform, supply-consumption balan...In light of carbon-neutral pledge, the oil and gas industry has been facing several critical new challenges in China. The current status and new challenges in terms of market mechanism reform, supply-consumption balance and key technology innovation in China's oil and gas industry are reviewed in the present study, and new strategies and roadmaps are proposed to cope with the challenges. The study found that (i) the oil and gas market faces challenges such as incomplete pricing mechanisms, unclear subject rights, and the lack of recognition and trading of carbon assets. (ii) the trade-off between short-term supply security and long-term low-carbon supply is the most critical issue. (iii) in addition to typical challenges such as immature technology and lack of funding support, the unclear multiple technology coupling development mode also poses problems for the low-carbon transformation of the oil and gas industry. To address these new challenges, comprehensive strategies and roadmaps for China's oil and gas industry towards carbon neutrality are proposed and discussed in the aspects of participating in market transactions, restructuring production and consumption, deploying key technology innovations, and planning enterprise strategies. The present study is expected to provide a blueprint for the future development of China's oil and gas industry towards carbon neutrality.展开更多
China is now beginning its 13 th five-year guideline.As the top CO_2 emitter,China has recently submitted the intended nationally determined contributions and made the commitment to start reducing its total carbon emi...China is now beginning its 13 th five-year guideline.As the top CO_2 emitter,China has recently submitted the intended nationally determined contributions and made the commitment to start reducing its total carbon emissions in or before 2030.In this study,a bottom-up energy system model is built and applied to analyze the energy(mainly coal,oil,and gas) consumption and carbon emissions in China up to 2030.The results show that,the total energy consumption will reach a peak of 58.1 billion tonnes of standard coal and the CO_2 emissions will get to105.8 billion tonnes.Moreover,in the mitigation scenario,proportion of natural gas consumption will increase by 7%in 2020 and 10%in 2030.respectively.In the transportation sector,gasoline and diesel consumption will gradually decrease,while the consumption of natural gas in2030 will increase by 2.7 times compared to the reference scenario.Moreover,with the promotion of electric cars,the transport electricity consumption will increase 3.1 times in2030 compared to the reference scenario.In order to fulfill the emission peaking target,efforts should be made from both the final demand sectors and oil and gas production industries,to help adjust the energy structure and ensure the oil and gas supply in future.展开更多
Objective: To investigate patients' perception of service quality at hospitals in nine Chinese cities and propose some measures for improvement. Methods: The ServQ ual scale method was used in a survey involving p...Objective: To investigate patients' perception of service quality at hospitals in nine Chinese cities and propose some measures for improvement. Methods: The ServQ ual scale method was used in a survey involving patients at out-patient and in-patient facilities in Shanghai, Chongqing, Chengdu, Nanning, Guilin and Laibin of Guangxi, Honghezhou of Yunnan, Wulumuqi of Xinjiang and Zhongshan of Guangdong. The data collected were entered and analyzed using SPSS 20.0. Statistical analyses included descriptive statistics, factor analyses, reliability analyses, product-moment correlations, independent-sample t-tests, One-way ANOVA and regression analyses. Results: The Kaiser-Meyer-Olkin value for the factor analysis of the scale was 0.979. The Cronbach's α for the reliability analysis was 0.978. All the Pearson correlation coei cients were positive and statistically signii cant. Visitors to out-patient facilities reported more positive perception tacilities on tangibles(t = 4.168, P(t = 1.979, P <han visitors to in-patient f 0.05). Patients of 60 years of age and above reported mor< 0.001) and reliability e positive perception th<an those between 40 and 49 on reliability(F = 3.311, P = 0.010), assurances(F = 2.751, P 0.05) and empathy(F = 4.009, P = 0.003). For the i ve dimensions of the scale, patients in Laibin, Guangxi reported the most positive perceived service quality, followed by patients in Shanghai. On the other hand, patients in Chongqing and Nanning and Guilin of Guangxi reported relatively poor perceptions of service quality. Standardized regression coei cients showed statistically significant(P < 0.001) positive values for all Serv Qual dimensions. Empathy(β = 0.267) and reliability(β uality. = 0.239) most strongly predicted perception of service qConclusions: Chinese patients perceived service quality as satisfactory. Hospitals in various regions of China should enhance their awareness and ability to serve their patients.展开更多
Natural gas is expected to play a much more important role in China in future decades, and market reform is crucial for its rapid market penetration. At present, the main gas fields, pipelines and liquefied natural ga...Natural gas is expected to play a much more important role in China in future decades, and market reform is crucial for its rapid market penetration. At present, the main gas fields, pipelines and liquefied natural gas(LNG) infrastructure are mainly monopolized by large state-owned companies, and one of the important market reform policies is to open up LNG import rights to smaller private companies and traders. Therefore, in the present study, a game theoretical model is proposed to analyze and compare the impacts of different market structures on infrastructure deployment and social welfare. Moreover, a support vector machine-based rolling horizon stochastic method is adopted in the model to simulate real LNG price fluctuations. Four market reform scenarios are proposed considering different policies such as business separation, third-party access(TPA) and their combinations. The results indicate that, with third-party access(TPA)entrance into the LNG market, the construction of LNG infrastructure will be promoted and more gas will be provided at lower prices, and thus the total social welfare will be improved greatly.展开更多
The petroleum industry plays an essential role in driving China's economic development.In the past few decades,severa reforms in the petroleum industry have been implemented;however,there are still some is sues th...The petroleum industry plays an essential role in driving China's economic development.In the past few decades,severa reforms in the petroleum industry have been implemented;however,there are still some is sues that have not been resolved Moreover,with the new-normal economy,the transition to green energy and international trade disputes,the petroleum marke is also facing emerging challenges.Therefore,the purpose of the present study is to review the historical development o China's petroleum market,identify the current challenges and propose corresponding countermeasures for future prospects As a conclusion,five main challenges are highlighted totally,namely lack of marketization,excess oil refining capacity,hig external dependency,environment pollution and unstable international trading relationship.To address these challenges it is encouraged to deepen petroleum market reform,accelerate the elimination of inefficient refining capacity,diversify of supply sources,as well as improve domestic petroleum enterprises'ability to resist price risks.展开更多
Keloid may induce severe impairment of life quality for the patients,although keloid is a cutaneous benign tumor.Collagen triple helix repeat containing protein 1 (Cthrc1) was identified as a novel gene that was origi...Keloid may induce severe impairment of life quality for the patients,although keloid is a cutaneous benign tumor.Collagen triple helix repeat containing protein 1 (Cthrc1) was identified as a novel gene that was originally found in adventitial fibroblasts after arterial injury.To address the role of Cthrcl in keloid,the expression level of Cthrcl was assessed in normal skin and keloid tissue,as well as in normal fibroblasts (NFs)and keloid fibroblasts (KFs)by using quantitative PCR,Western blotting and immunohistochemical analysis.The results showed that Cthrcl was increased in keloid tissue and KFs as compared with normal skin and NFs.Meanwhile,CCK8 and Transwell assays found the cellular proliferation and migration of KFs were increased as compared with NFs.Further,to verify the function of Cthrcl in NFs and K.Fs,we increased Cthrcl expression by transfecting lentivirns (LV) vectors LV-Cthrcl.The cellular proliferation and migration,collagen synthesis and the influence on TGF-β and YAP signaling were tested.The cellular proliferation and migration were increased in NFs-Cthrcl as compared with NFs-control.Meanwhile,YAP expression and nuclear-location was increased in NFs-Cthrcl.On the contrary,when Cthrcl was overexpressed in KFs,the cellular migration was suppressed and YAP expression was reduced and transferred to cytoplasm in KFs-Cthrcl as compared with KFs-control.But the expression level of collagen I was decreased and pSmad2/3 nucleus transfer was suppressed in both NFs-Cthrc1 and KFs-Cthrc1 by using Western blotting and immunofluorescence.Increased Cthrcl activated NFs by promoting YAP nucleus translocation,whereas suppressed KFs by inhibiting YAP nucleus translocation.Enhanced Cthrcl decreased collagen I in both NFs and KFs by inhibiting TGF-β/Smad pathway.In conclusion,Cthrcl may play a role in the pathogenesis of keloid by inhibiting collagen synthesis and fibroblasts migration via suppressing TGF-β/Smad pathway and YAP nucleus translocation.展开更多
Objective:To study the effect of aspirin on healing process of osteoporotic fracture(OPF)in rats.Methods:A total of 50 female Wistar rata aged 3 months were randomly divided into observation group and control group,ca...Objective:To study the effect of aspirin on healing process of osteoporotic fracture(OPF)in rats.Methods:A total of 50 female Wistar rata aged 3 months were randomly divided into observation group and control group,castration method was adopted to establish the osteoporosis(OP)model.After artificial preparing fractures on the midpoint of left femur,fixing gram needle intramedullary.OPF modeling was complete.Aspirin lavage of 33 mg once a day was adoptde in observation group after modeling,same amount of normal saline was used in the control as placebo.From eash group,selected 5 rats at the 2nd.4th,8th and 12th week after modeling to measure the bone mineral density(BMD)and histogical examination of the fracture callus,radiology observation was conducted at the 8th and 12th week.Left femur biomechanical measurement was taken at the 12th week.Results:BMD values of observation group at each time point were significantly higher than that of the control group after modeling(P<0.05);Histological observation showed that at the 8th week,the endochondral ossification process of observation group was faster than that of observation group,with fuzzy fracture line in observation group and clear fracture line in observtion group;at the 12th week,fracture line disappeared in observation group,fracture line of the control group was fuzzy at the same time;three-point bending load of the left femur in observation group rats was significantly higher than that of control group after12 weeka(P<0.05).Conclusions:Asporin can accelerate the healing of new callus in OPF rats,increase bone density and biomechanics strength,and promote fracture of osteporotic rats.展开更多
We investigate the synergism effect of total ionizing dose(TID)on single-event burnout(SEB)for commercial enhancement-mode AlGaN/GaN high-electron mobility transistors.Our experimental results show that the slight deg...We investigate the synergism effect of total ionizing dose(TID)on single-event burnout(SEB)for commercial enhancement-mode AlGaN/GaN high-electron mobility transistors.Our experimental results show that the slight degradation of devices caused by gamma rays can affect the stability of the devices during the impact of high energy particles.During heavy ion irradiation,the safe working values of drain voltage are significantly reduced for devices which have already been irradiated by 60Co gamma rays before.This could be attributed to more charges trapped caused by 60Co gamma rays,which make GaN devices more vulnerable to SEB.Moreover,the electrical parameters of GaN devices after 60Co gamma and heavy-ion irradiations are presented,such as the output characteristic curve,effective threshold voltages,and leakage current of drain.These results demonstrate that the synergistic effect of TID on SEB for GaN power devices does in fact exist.展开更多
Proppant plays a significant role in the hydraulic fracturing process, which can affect the production of oil and gas wells. Due to the high density and low adhesion force, the settling speed of traditional proppants ...Proppant plays a significant role in the hydraulic fracturing process, which can affect the production of oil and gas wells. Due to the high density and low adhesion force, the settling speed of traditional proppants is fast, which will lead to the blockage of a crack channel. In this study, a proppant with double layer structure is fabricated by coating epoxy-resin and shaly detritus on ceramic proppants for the first time,respectively. The epoxy-resin enables the shaly detritus to be coated on the proppant successfully, which can provide a new method for shaly detritus treatment. The adhesive ability of shaly detritus and epoxyresin coated proppants(SEPs) is improved by 10.4% under the load force of 500 n N, which prolongs the time for the fracture to close. At the same time, the suspending ability of SEPs is two times higher than the uncoated proppants. Once the guar gum solution concentration is 0.3 wt%, the settling time of SEPs is36.7% longer than that of the uncoated proppants, which can effectively reduce the settlement of proppants in the crack. In addition, the hydrophobicity of the SEPs is enhanced, which reduces the wateroil ratio of crude oil and increases the liquid conductivity tested by deionized water. In summary, this new proppant is expected to promote the development of unconventional oil and gas resources.展开更多
Background:The National Comprehensive Cancer Network guidelines recommend intensity-modulated radiotherapy(IMRT)as the primary curative treatment for newly diagnosed nasopharyngeal carcinoma(NPC),but the radiation-rel...Background:The National Comprehensive Cancer Network guidelines recommend intensity-modulated radiotherapy(IMRT)as the primary curative treatment for newly diagnosed nasopharyngeal carcinoma(NPC),but the radiation-related complications and relatively high medical costs remain a consequential burden for the patients.Endoscopic nasopharyngectomy(ENPG)was successfully applied in recurrent NPC with radiation free and relatively low medical costs.In this study,we examined whether ENPG could be an effective treatment for localized stage I NPC.Methods:Ten newly diagnosed localized stage I NPC patients voluntarily received ENPG alone from June 2007 to September 2017 in Sun Yat-sen University Cancer Center.Simultaneously,the data of 329 stage I NPC patients treated with IMRT were collected and used as a reference cohort.The survival outcomes,quality of life(QOL),and medical costs between two groups were compared.Results:After a median follow-up of 59.0 months(95%CI 53.4-64.6),no death,locoregional recurrence,or distant metastasis was observed in the 10 patients treated with ENPG.The 5-year overall survival,local relapse-free survival,regional relapse-free survival,and distant metastasis-free survival among the ENPG-treated patients was similar to that among the IMRT-treated patients(100%vs.99.1%,100%vs.97.7%,100%vs.99.0%,100%vs.97.4%,respectively,P>0.05).In addition,compared with IMRT,ENPG was associated with decreased total medical costs($4090.42±1502.65 vs.$12620.88±4242.65,P<0.001)and improved QOL scores including dry mouth(3.3±10.5 vs.34.4±25.8,P<0.001)and sticky saliva(3.3±10.5 vs.32.6±23.3,P<0.001).Conclusions:ENPG alone was associated with promising long-term survival outcomes,low medical costs,and satisfactory QOL and might therefore be an alternative strategy for treating newly diagnosed localized stage I NPC patients who refused radiotherapy.However,the application of ENPG should be prudent,and prospective clinical tri-als were needed to further verify the results.展开更多
Background The aim of this study was to evaluate the performance of the four scoring tools in predicting mortality in pediatric intensive care units(PICUs)in western China.Methods This was a multicenter,prospective,co...Background The aim of this study was to evaluate the performance of the four scoring tools in predicting mortality in pediatric intensive care units(PICUs)in western China.Methods This was a multicenter,prospective,cohort study conducted in six PICUs in western China.The performances of the scoring systems were evaluated based on both discrimination and calibration.Discrimination was assessed by calculating the area under the receiver operating characteristic curve(AUC)for each model.Calibration was measured across defined groups based on mortality risk using the Hosmer-Lemeshow goodness-of-fit test.Results A total of 2034 patients were included in this study,of whom 127(6.2%)died.For the entire cohort,AUCs for Pediatric Risk of Mortality Score(PRISM)I,Pediatric Index of Mortality 2(PIM2),Pediatric Logistic Organ Dysfunction Score-2(PELOD-2)and PRISM IV were 0.88[95%confidence interval(CI)0.85–0.92],0.84(95%CI 0.80–0.88),0.80(95%CI 0.75–0.85),and 0.91(95%CI 0.88–0.94),respectively.The Hosmer-Lemeshow goodness-of-fit Chi-square value was 12.71(P=0.12)for PRISM I,4.70(P=0.79)for PIM2,205.98(P<0.001)for PELOD-2,and 7.50(P=0.48)for PRISM IV[degree of freedom(df)=8].The standardized mortality ratios obtained with the PRISM I,PIM2,PELOD-2,and PRISM IV models were 0.87(95%CI,0.75–1.01),0.97(95%CI,0.85–1.12),1.74(95%CI,1.58–1.92),and 1.05(95%CI,0.92–1.21),respectively.Conclusions PRISM IV performed best and can be used as a prediction tool in PICUs in Western China.However,PRISM IV needs to be further validated in NICUs.展开更多
基金support provided by the Major Program of National Social Science Foundation of China(No.21ZDA030)Natural Science Foundation of Xinjiang(No.2022D01E56)Open Research Fund of Tianshan Research Institute(No.TSKF20220010).
文摘In light of carbon-neutral pledge, the oil and gas industry has been facing several critical new challenges in China. The current status and new challenges in terms of market mechanism reform, supply-consumption balance and key technology innovation in China's oil and gas industry are reviewed in the present study, and new strategies and roadmaps are proposed to cope with the challenges. The study found that (i) the oil and gas market faces challenges such as incomplete pricing mechanisms, unclear subject rights, and the lack of recognition and trading of carbon assets. (ii) the trade-off between short-term supply security and long-term low-carbon supply is the most critical issue. (iii) in addition to typical challenges such as immature technology and lack of funding support, the unclear multiple technology coupling development mode also poses problems for the low-carbon transformation of the oil and gas industry. To address these new challenges, comprehensive strategies and roadmaps for China's oil and gas industry towards carbon neutrality are proposed and discussed in the aspects of participating in market transactions, restructuring production and consumption, deploying key technology innovations, and planning enterprise strategies. The present study is expected to provide a blueprint for the future development of China's oil and gas industry towards carbon neutrality.
基金funded by the Project supported by China National Petroleum Corporation(Project Name:The development trend of oil and gas industry till 2030Project Number:20150114)
文摘China is now beginning its 13 th five-year guideline.As the top CO_2 emitter,China has recently submitted the intended nationally determined contributions and made the commitment to start reducing its total carbon emissions in or before 2030.In this study,a bottom-up energy system model is built and applied to analyze the energy(mainly coal,oil,and gas) consumption and carbon emissions in China up to 2030.The results show that,the total energy consumption will reach a peak of 58.1 billion tonnes of standard coal and the CO_2 emissions will get to105.8 billion tonnes.Moreover,in the mitigation scenario,proportion of natural gas consumption will increase by 7%in 2020 and 10%in 2030.respectively.In the transportation sector,gasoline and diesel consumption will gradually decrease,while the consumption of natural gas in2030 will increase by 2.7 times compared to the reference scenario.Moreover,with the promotion of electric cars,the transport electricity consumption will increase 3.1 times in2030 compared to the reference scenario.In order to fulfill the emission peaking target,efforts should be made from both the final demand sectors and oil and gas production industries,to help adjust the energy structure and ensure the oil and gas supply in future.
基金Supported by the 12th Five-Year Infectious Disease Research Project:the Use and Optimization of the Standard Regimen for Diagnosis and Treatment of Tuberculosis in HIV/AIDS Patients in China(No.2012ZX10001-003)the 12th Five-Year Major Science and Technology Project on Discovery of Major New Drugs:Construction of a Technology Platform for Clinical Evaluation of AntiHIV Drugs(No.2012ZX09303013)+2 种基金the National 863 Project"Study the Key Technology of Personnel Protection and Lab Tracking of pathogenic microorganism"(2014AA021403)the year 2014 Key research project of the party of the education and health of Shanghai(201420)Scientific research in hospital construction project of Chinese Medical Doctor Assoclation
文摘Objective: To investigate patients' perception of service quality at hospitals in nine Chinese cities and propose some measures for improvement. Methods: The ServQ ual scale method was used in a survey involving patients at out-patient and in-patient facilities in Shanghai, Chongqing, Chengdu, Nanning, Guilin and Laibin of Guangxi, Honghezhou of Yunnan, Wulumuqi of Xinjiang and Zhongshan of Guangdong. The data collected were entered and analyzed using SPSS 20.0. Statistical analyses included descriptive statistics, factor analyses, reliability analyses, product-moment correlations, independent-sample t-tests, One-way ANOVA and regression analyses. Results: The Kaiser-Meyer-Olkin value for the factor analysis of the scale was 0.979. The Cronbach's α for the reliability analysis was 0.978. All the Pearson correlation coei cients were positive and statistically signii cant. Visitors to out-patient facilities reported more positive perception tacilities on tangibles(t = 4.168, P(t = 1.979, P <han visitors to in-patient f 0.05). Patients of 60 years of age and above reported mor< 0.001) and reliability e positive perception th<an those between 40 and 49 on reliability(F = 3.311, P = 0.010), assurances(F = 2.751, P 0.05) and empathy(F = 4.009, P = 0.003). For the i ve dimensions of the scale, patients in Laibin, Guangxi reported the most positive perceived service quality, followed by patients in Shanghai. On the other hand, patients in Chongqing and Nanning and Guilin of Guangxi reported relatively poor perceptions of service quality. Standardized regression coei cients showed statistically significant(P < 0.001) positive values for all Serv Qual dimensions. Empathy(β = 0.267) and reliability(β uality. = 0.239) most strongly predicted perception of service qConclusions: Chinese patients perceived service quality as satisfactory. Hospitals in various regions of China should enhance their awareness and ability to serve their patients.
基金financial support of the National Natural Science Foundation of China (Grant No. 71774171)Science Foundation of China University of Petroleum, Beijing (No. 2462017YB11)
文摘Natural gas is expected to play a much more important role in China in future decades, and market reform is crucial for its rapid market penetration. At present, the main gas fields, pipelines and liquefied natural gas(LNG) infrastructure are mainly monopolized by large state-owned companies, and one of the important market reform policies is to open up LNG import rights to smaller private companies and traders. Therefore, in the present study, a game theoretical model is proposed to analyze and compare the impacts of different market structures on infrastructure deployment and social welfare. Moreover, a support vector machine-based rolling horizon stochastic method is adopted in the model to simulate real LNG price fluctuations. Four market reform scenarios are proposed considering different policies such as business separation, third-party access(TPA) and their combinations. The results indicate that, with third-party access(TPA)entrance into the LNG market, the construction of LNG infrastructure will be promoted and more gas will be provided at lower prices, and thus the total social welfare will be improved greatly.
基金support provided by the National Natural Science Foundation of China(Nos.71974197 and 71774171)Beijing Social Science Fund(No.18GLC084)。
文摘The petroleum industry plays an essential role in driving China's economic development.In the past few decades,severa reforms in the petroleum industry have been implemented;however,there are still some is sues that have not been resolved Moreover,with the new-normal economy,the transition to green energy and international trade disputes,the petroleum marke is also facing emerging challenges.Therefore,the purpose of the present study is to review the historical development o China's petroleum market,identify the current challenges and propose corresponding countermeasures for future prospects As a conclusion,five main challenges are highlighted totally,namely lack of marketization,excess oil refining capacity,hig external dependency,environment pollution and unstable international trading relationship.To address these challenges it is encouraged to deepen petroleum market reform,accelerate the elimination of inefficient refining capacity,diversify of supply sources,as well as improve domestic petroleum enterprises'ability to resist price risks.
基金This work was supported by the National Natural Science Foundation of China (No.81472886 and No. 81172588).
文摘Keloid may induce severe impairment of life quality for the patients,although keloid is a cutaneous benign tumor.Collagen triple helix repeat containing protein 1 (Cthrc1) was identified as a novel gene that was originally found in adventitial fibroblasts after arterial injury.To address the role of Cthrcl in keloid,the expression level of Cthrcl was assessed in normal skin and keloid tissue,as well as in normal fibroblasts (NFs)and keloid fibroblasts (KFs)by using quantitative PCR,Western blotting and immunohistochemical analysis.The results showed that Cthrcl was increased in keloid tissue and KFs as compared with normal skin and NFs.Meanwhile,CCK8 and Transwell assays found the cellular proliferation and migration of KFs were increased as compared with NFs.Further,to verify the function of Cthrcl in NFs and K.Fs,we increased Cthrcl expression by transfecting lentivirns (LV) vectors LV-Cthrcl.The cellular proliferation and migration,collagen synthesis and the influence on TGF-β and YAP signaling were tested.The cellular proliferation and migration were increased in NFs-Cthrcl as compared with NFs-control.Meanwhile,YAP expression and nuclear-location was increased in NFs-Cthrcl.On the contrary,when Cthrcl was overexpressed in KFs,the cellular migration was suppressed and YAP expression was reduced and transferred to cytoplasm in KFs-Cthrcl as compared with KFs-control.But the expression level of collagen I was decreased and pSmad2/3 nucleus transfer was suppressed in both NFs-Cthrc1 and KFs-Cthrc1 by using Western blotting and immunofluorescence.Increased Cthrcl activated NFs by promoting YAP nucleus translocation,whereas suppressed KFs by inhibiting YAP nucleus translocation.Enhanced Cthrcl decreased collagen I in both NFs and KFs by inhibiting TGF-β/Smad pathway.In conclusion,Cthrcl may play a role in the pathogenesis of keloid by inhibiting collagen synthesis and fibroblasts migration via suppressing TGF-β/Smad pathway and YAP nucleus translocation.
基金supported by Guangdong Science and Technology Projects,grant No.2010b031600288
文摘Objective:To study the effect of aspirin on healing process of osteoporotic fracture(OPF)in rats.Methods:A total of 50 female Wistar rata aged 3 months were randomly divided into observation group and control group,castration method was adopted to establish the osteoporosis(OP)model.After artificial preparing fractures on the midpoint of left femur,fixing gram needle intramedullary.OPF modeling was complete.Aspirin lavage of 33 mg once a day was adoptde in observation group after modeling,same amount of normal saline was used in the control as placebo.From eash group,selected 5 rats at the 2nd.4th,8th and 12th week after modeling to measure the bone mineral density(BMD)and histogical examination of the fracture callus,radiology observation was conducted at the 8th and 12th week.Left femur biomechanical measurement was taken at the 12th week.Results:BMD values of observation group at each time point were significantly higher than that of the control group after modeling(P<0.05);Histological observation showed that at the 8th week,the endochondral ossification process of observation group was faster than that of observation group,with fuzzy fracture line in observation group and clear fracture line in observtion group;at the 12th week,fracture line disappeared in observation group,fracture line of the control group was fuzzy at the same time;three-point bending load of the left femur in observation group rats was significantly higher than that of control group after12 weeka(P<0.05).Conclusions:Asporin can accelerate the healing of new callus in OPF rats,increase bone density and biomechanics strength,and promote fracture of osteporotic rats.
基金Supported by the National Natural Science Foundation of China under Grant Nos. U1532261,U1630141,and 61534008the West Light Foundation of Chinese Academy of Sciences under Grant No. 2018-XBQNXZ-B-003
文摘We investigate the synergism effect of total ionizing dose(TID)on single-event burnout(SEB)for commercial enhancement-mode AlGaN/GaN high-electron mobility transistors.Our experimental results show that the slight degradation of devices caused by gamma rays can affect the stability of the devices during the impact of high energy particles.During heavy ion irradiation,the safe working values of drain voltage are significantly reduced for devices which have already been irradiated by 60Co gamma rays before.This could be attributed to more charges trapped caused by 60Co gamma rays,which make GaN devices more vulnerable to SEB.Moreover,the electrical parameters of GaN devices after 60Co gamma and heavy-ion irradiations are presented,such as the output characteristic curve,effective threshold voltages,and leakage current of drain.These results demonstrate that the synergistic effect of TID on SEB for GaN power devices does in fact exist.
基金supported by the National Key Research and Development Program of China (Grant No. 2020YFC1808102)National Natural Science Foundation of China (No. 52074059)+1 种基金Chongqing Science Foundation for Distinguished Young Scholars(cstc2021jcyj-jqX0007)Science Foundation of China University of Petroleum,Beijing (Nos. 2462019BJRC007, 2462019QNXZ02)。
文摘Proppant plays a significant role in the hydraulic fracturing process, which can affect the production of oil and gas wells. Due to the high density and low adhesion force, the settling speed of traditional proppants is fast, which will lead to the blockage of a crack channel. In this study, a proppant with double layer structure is fabricated by coating epoxy-resin and shaly detritus on ceramic proppants for the first time,respectively. The epoxy-resin enables the shaly detritus to be coated on the proppant successfully, which can provide a new method for shaly detritus treatment. The adhesive ability of shaly detritus and epoxyresin coated proppants(SEPs) is improved by 10.4% under the load force of 500 n N, which prolongs the time for the fracture to close. At the same time, the suspending ability of SEPs is two times higher than the uncoated proppants. Once the guar gum solution concentration is 0.3 wt%, the settling time of SEPs is36.7% longer than that of the uncoated proppants, which can effectively reduce the settlement of proppants in the crack. In addition, the hydrophobicity of the SEPs is enhanced, which reduces the wateroil ratio of crude oil and increases the liquid conductivity tested by deionized water. In summary, this new proppant is expected to promote the development of unconventional oil and gas resources.
基金Funding was provided by the National Natural Science Foundation of China(Nos.81572912,81772895)Guangdong Public Welfare Research and Capacity Building Projects(2014B020212005)+1 种基金the Program of Sun Yat-Sen University for Clinical Research 5010 Program(No.201310)the Major Project of Sun Yat-Sen University for the New Cross Subject,the Special Support Program for High-level Talents in Sun Yat-Sen University Cancer Center(to M.Y.Chen),Guangdong Province Science and Technology Development Special Funds(Frontier and Key Technology Innovation Direction-Major Science and Technology Project),Guangzhou Science and Technology Planning Project-Production and Research Collaborative Innovation Major Project
文摘Background:The National Comprehensive Cancer Network guidelines recommend intensity-modulated radiotherapy(IMRT)as the primary curative treatment for newly diagnosed nasopharyngeal carcinoma(NPC),but the radiation-related complications and relatively high medical costs remain a consequential burden for the patients.Endoscopic nasopharyngectomy(ENPG)was successfully applied in recurrent NPC with radiation free and relatively low medical costs.In this study,we examined whether ENPG could be an effective treatment for localized stage I NPC.Methods:Ten newly diagnosed localized stage I NPC patients voluntarily received ENPG alone from June 2007 to September 2017 in Sun Yat-sen University Cancer Center.Simultaneously,the data of 329 stage I NPC patients treated with IMRT were collected and used as a reference cohort.The survival outcomes,quality of life(QOL),and medical costs between two groups were compared.Results:After a median follow-up of 59.0 months(95%CI 53.4-64.6),no death,locoregional recurrence,or distant metastasis was observed in the 10 patients treated with ENPG.The 5-year overall survival,local relapse-free survival,regional relapse-free survival,and distant metastasis-free survival among the ENPG-treated patients was similar to that among the IMRT-treated patients(100%vs.99.1%,100%vs.97.7%,100%vs.99.0%,100%vs.97.4%,respectively,P>0.05).In addition,compared with IMRT,ENPG was associated with decreased total medical costs($4090.42±1502.65 vs.$12620.88±4242.65,P<0.001)and improved QOL scores including dry mouth(3.3±10.5 vs.34.4±25.8,P<0.001)and sticky saliva(3.3±10.5 vs.32.6±23.3,P<0.001).Conclusions:ENPG alone was associated with promising long-term survival outcomes,low medical costs,and satisfactory QOL and might therefore be an alternative strategy for treating newly diagnosed localized stage I NPC patients who refused radiotherapy.However,the application of ENPG should be prudent,and prospective clinical tri-als were needed to further verify the results.
基金supported by the National Natural Science Foundation of China(Grant Numbers 81400862 and 81401606)the Key Project of the Science&Technology Program of Sichuan Province(Grant Number 2019YFS0322)+1 种基金the Science Foundation for The Excellent Youth Scholars of Sichuan University(grant number 2015SU04A15)the 1·3·5 Project for Disciplines of Excellence,West China Hospital of Sichuan University(Grant Numbers 2019HXFH056,2020HXFH048 and YJC21060).
文摘Background The aim of this study was to evaluate the performance of the four scoring tools in predicting mortality in pediatric intensive care units(PICUs)in western China.Methods This was a multicenter,prospective,cohort study conducted in six PICUs in western China.The performances of the scoring systems were evaluated based on both discrimination and calibration.Discrimination was assessed by calculating the area under the receiver operating characteristic curve(AUC)for each model.Calibration was measured across defined groups based on mortality risk using the Hosmer-Lemeshow goodness-of-fit test.Results A total of 2034 patients were included in this study,of whom 127(6.2%)died.For the entire cohort,AUCs for Pediatric Risk of Mortality Score(PRISM)I,Pediatric Index of Mortality 2(PIM2),Pediatric Logistic Organ Dysfunction Score-2(PELOD-2)and PRISM IV were 0.88[95%confidence interval(CI)0.85–0.92],0.84(95%CI 0.80–0.88),0.80(95%CI 0.75–0.85),and 0.91(95%CI 0.88–0.94),respectively.The Hosmer-Lemeshow goodness-of-fit Chi-square value was 12.71(P=0.12)for PRISM I,4.70(P=0.79)for PIM2,205.98(P<0.001)for PELOD-2,and 7.50(P=0.48)for PRISM IV[degree of freedom(df)=8].The standardized mortality ratios obtained with the PRISM I,PIM2,PELOD-2,and PRISM IV models were 0.87(95%CI,0.75–1.01),0.97(95%CI,0.85–1.12),1.74(95%CI,1.58–1.92),and 1.05(95%CI,0.92–1.21),respectively.Conclusions PRISM IV performed best and can be used as a prediction tool in PICUs in Western China.However,PRISM IV needs to be further validated in NICUs.
