The battlefield treatments of spinal and spinal cord injury vary from civilian settings. However, there is no unified battlefield treatment guidelines for spine trauma in PLA. An expert consensus is reached, based on ...The battlefield treatments of spinal and spinal cord injury vary from civilian settings. However, there is no unified battlefield treatment guidelines for spine trauma in PLA. An expert consensus is reached, based on spine trauma epidemiology and the concepts of battlefield treatment combined with the existing levels of military medical care in modern warfare. Since the specialized treatment for spine trauma are no significant difference between civilian settings and modern war, the first aid, emergency treatment and early treatment of spine trauma are introduced separately in three levels in this consensus. In Level I facilities, the fast and accurate evaluation of spine trauma followed by fixation and stabilization are recommended during the first-aid stage. Re-evaluation, further treatment for possible hemorrhagic shock, dyspnea and infection are recommended at Level II facilities. At Level III facilities, it is recommended to strengthen the intensive care and the prevention of urinary system and lung infection for the wounded with severe spinal injury, however, spinal surgery is not recommended in a battlefield hospital. The grading standard for evidence evaluation and recommendation was used to reach this expert consensus.展开更多
Various virulence-associated genes or pathogenicity island are responsible for determining the pathogenicity of Escherichia coli strains. However, the correlation of the number and combination patterns of virulence-as...Various virulence-associated genes or pathogenicity island are responsible for determining the pathogenicity of Escherichia coli strains. However, the correlation of the number and combination patterns of virulence-associated genes in Escherichia coli strains with their pathogenicity remains largely unknown. In this work, 581 chicken Escherichia coli strains were isolated from 1045 liver samples of dead chickens from 50 chicken farms at four provinces in China during 2007-2012. Based on the pathogenic test of SPF chickens, 320 chickens pathogenic Escherichia coli isolates were identified as highly (n = 193), intermediate (n = 98) and low pathogenic (n = 29) strains, respectively. Furthermore, the number of virulence genes in the 320 chicken pathogenic and 50 non-pathogenic Escherichia coli strains was examined. Our results reveal that thirteen virulence genes in Escherichia coli strains were detected, and all strains carried at least two or more than two virulence-associated genes. This study also suggests that highly pathogenic E. coli strains simultaneously carried at least 8 to13 virulence genes while intermediate pathogenic strains carried at least 5 to 8 virulence genes. The number of virulence-associated genes detected in highly pathogenic strains showed there were more significant differences than that in low pathogenic strains (P irp2, fyuA, and colV in high pathogenic strains was significantly higher than that in low and non-pathogenic strains (P irp2, fyuA, iucA, iucD, iutA, papC, iss, tsh, and colV were more often detected in highly and intermediate pathogenic E. coli strains. Taken together, our results provide evidences demonstrating that the pathogenicity of Escherichia coli strains is closely associated with the number and combination patterns of virulence-associated genes.展开更多
BACKGROUND A radicular groove is an anatomic malformation that usually initiates at the central fossa,extending along the root at varying lengths and depths and predisposes the involved tooth to a severe periodontal d...BACKGROUND A radicular groove is an anatomic malformation that usually initiates at the central fossa,extending along the root at varying lengths and depths and predisposes the involved tooth to a severe periodontal defect.Severe grooves that extend to the root apex often lead to complex combined periodontal-endodontic lesions.They are a serious challenge for doctors to diagnose and treat.CASE SUMMARY In this report,we described a patient with a maxillary lateral incisor with a deep palatogingival groove with two roots,which led to complex combined periodontal-endodontic lesions.Suggested treatment modalities included curettage of the affected tissues,elimination of the groove by grinding and/or sealing with a variety of filling materials,and surgical procedures.In this case,a combination of endodontic therapy,intentional replantation,and root resection were used,which resulted in periodontal/periradicular healing after 12 mo.CONCLUSION Intentional replantation and root resection offer a predictable procedure and should be considered a viable treatment modality for the management of palatogingival grooves,especially for two-rooted teeth.展开更多
Reporter genes are widely applied in biotechnology and biomedical research owning to their easy observation and lack of toxicity. Taking advantage of the reporter genes in conjunction with imaging technologies, a larg...Reporter genes are widely applied in biotechnology and biomedical research owning to their easy observation and lack of toxicity. Taking advantage of the reporter genes in conjunction with imaging technologies, a large number of reporter mouse models have been generated. Reporter mouse models provide systems that enable the studies of live cell imaging, cell lineage tracing, immunological research and cancers etc. in vivo. In this review, we describe the types of different reporter genes and reporter mouse models including, random reporter strains, Cre reporter strains and ROSA26 reporter strains. Collectively, these reporter mouse models have broadened scientific inquires and provided potential strategies for generation of novel reporter animal models with enhanced capabilities.展开更多
As the world pays more attention to low-earbon and sustainable development,there's a growing trend in architecture,engineering and construction fields to construct greener,more energy efficient and more sustainabl...As the world pays more attention to low-earbon and sustainable development,there's a growing trend in architecture,engineering and construction fields to construct greener,more energy efficient and more sustainable buildings with the help of building information modeling(BIM).As BIM application becomes popular in industry,more and more scholars and engineers point out that an integrated construction environment is better for BIM's fully functional capability.This paper illustrates the relationship between BIM application and an integrated construction environment based on case survey data.It is found that even though an integration construction environment is not necessary in BIM application,the statistical results showed that DBB(design-bid-build)and CM(construction management)modes have great differences in BIM's application implementation scope and implementation deepness,while DB and CM modes do not.展开更多
Objective: To explore the effect of thymalfasin on coagulation index, immune function, PCT and sTREM-1 levels in patients with community acquired pneumonia. Methods: 160 patients with community acquired pneumonia admi...Objective: To explore the effect of thymalfasin on coagulation index, immune function, PCT and sTREM-1 levels in patients with community acquired pneumonia. Methods: 160 patients with community acquired pneumonia admitted in our hospital from June 2016-June 2017 were divided into the control group and the observation group according to the random number table method, each 80 cases. The control group was given conventional treatment, while the observation group was given thymalfasin on the basis of conventional treatment. The levels of D-D, FBG, complement C3, C4, T lymphocyte subsets, PCT and sTREM-1 were detected before and after treatment. Results: Before treatment, there was no statistical difference between the serum levels of D-D, FBG, C3, C4, CD3+,CD4+,CD8+,CD4+/CD8+, PCT and sTREM-1 in the two groups of patients, and P>0.05. After treatment, the levels of CD3+, CD4+and CD4+/CD8+ in the control group and the observation group were significantly increased, and the levels of D-D, FBG, CD8+, PCT and sTREM-1 were significantly decreased, and the level of CD3+, CD4+ and CD4+/CD8+ in the observation group was significantly higher than that of the control group after treatment, and the D-D, FBG, CD8+, PCT and sTREM-1 levels were significantly lower than those in the control group, the difference was statistically significant, P<0.05. Conclusion: Thymalfasin has a certain clinical effect in the treatment of patients with community acquired pneumonia. It can significantly improve the blood coagulation function, enhance the immune ability and alleviate the inflammatory state.展开更多
Hydrogen bonds are non-covalent interactions and essential for assembling supermolecules into ordered structures in biological systems,endowing crystals with fascinating physical properties,and inspiring the construct...Hydrogen bonds are non-covalent interactions and essential for assembling supermolecules into ordered structures in biological systems,endowing crystals with fascinating physical properties,and inspiring the construction of eco-friendly electromechanical devices.However,the interplay between hydrogen bonding and the physical properties is not fully understood at the molecular level.Herein,we demonstrate that the physical property of biological crystals with double-layer structures could be enhanced by rationally controlling hydrogen bonding interactions between amino and carboxyl groups.Different hydrogen bonding interactions result in various thermal,mechanical,electronic,and piezoelectric properties.In particular,the weak interaction between O and H atoms contributes to low mechanical strength that permits important ion displacement under stress,giving rise to a strong piezoelectric response.This study not only reveals the correlation between the hydrogen bonding and physical properties in double-layer structures of biological crystals but also demonstrates the potential of these crystals as functional biomaterials for high-performance energy-harvesting devices.Theoretical calculations and experimental verifications in this work provide new insights into the rational design of biomaterials with desirable physical properties for bioelectrical devices by modulating intermolecular interactions.展开更多
Purpose::To investigate the clinical value of urine interleukin-18(IL-8),neutrophil gelatinase-associated lipocalin(NGAL)and kidney injury molecule-1(KIM-1)for the early diagnosis of acute kidney injury(AKI)in patient...Purpose::To investigate the clinical value of urine interleukin-18(IL-8),neutrophil gelatinase-associated lipocalin(NGAL)and kidney injury molecule-1(KIM-1)for the early diagnosis of acute kidney injury(AKI)in patients with ureteroscopic lithotripsy(URL)related urosepsis.Methods::A retrospective study was carried out in 157 patients with urosepsis after URL.The patients were divided into AKI group and non-AKI group according to the Kidigo guideline and urine IL-8,NGAL and KIM-1 levels were detected by enzyme-linked immunosorbent assay at 0,4,12,24 and 48 h after the surgery.Receiver operating characteristic curve(ROC)was used to evaluate the diagnostic value of these three biomarkers for postoperative AKI.Results::The level of urine IL-8,NGAL and KIM-1 in AKI group was significantly higher than that in non-AKI group at 4,12,24 and 48 h(p<0.01).The ROC analysis showed the combined detection of urine IL-8,NGAL and KIM-1 at 12 h had a larger area under curve(AUC)than a single marker(0.997,95%CI:0.991-0.998),and the sensitivity and specificity were 98.2%and 96.7%,respectively.Pearson correlation analysis showed that the levels of urine NGAL at 4,12,24 and 48 h in AKI patients were positively correlated with the levels of urine KIM-1 and IL-18(p<0.01).Conclusion::AKI could be quickly recognized by the elevated level of urine IL-8,NGAL and KIM-1 in patients with URL-related urosepsis.Combined detection of the three urine biomarkers at 12 h after surgery had a better diagnostic performance,which may be an important reference for the early diagnosis of AKI.展开更多
Assembly of eukaryotic ribosome is a complicated and dynamic process that involves a series of intermediates.It is unknown how the highly intertwined structure of 60S large ribosomal subunits is established.Here,we re...Assembly of eukaryotic ribosome is a complicated and dynamic process that involves a series of intermediates.It is unknown how the highly intertwined structure of 60S large ribosomal subunits is established.Here,we report the structure of an early nucleolar pre-60S ribosome determined by cryo-electron microscopy at 3.7 A resolution,revealing a half-assembled subunit.DomainsⅠ,ⅡandⅣof 25S/5.8S rRNA pack tightly into a native-like substructure,but domains Ⅲ,ⅣandⅤare not assembled.The structure contains 12 assembly factors and 19 ribosomal proteins,many of which are required for early processing of large subunit rRNA.The Brx1-Ebp2 complex would interfere with the assembly of domains Ⅳ and Ⅴ.Rpf1,Mak16,Nsa1 and Rrp1 form a cluster that consolidates the joining of domainsⅠandⅡ.Our structure reveals a key intermediate on the path to establishing the global architecture of 60S subunits.展开更多
Because of global warming,people have paid more attention to greenhouse gas emitted by vehicles.To quantify the impact of temperature on vehicle CO_(2)emissions,this study was conducted using the world light vehicle t...Because of global warming,people have paid more attention to greenhouse gas emitted by vehicles.To quantify the impact of temperature on vehicle CO_(2)emissions,this study was conducted using the world light vehicle test cycle on two light-duty E10 gasoline vehicles a ambient temperatures of-10,0,23,and 40℃,and found that CO_(2)emission factors of Vehicle1 in the low-speed phase were 22.07%and 20.22%higher than those of Vehicle 2 at cold star and hot start under-10℃.The reason was vehicle 1 had a larger displacement and more friction pairs than vehicle 2.There was the highest CO_(2)emission at the low-speed phase due to low average speed,frequent acceleration,and deceleration.The CO_(2)temperature factor and the ambient temperature had a strong linear correlation(R2=0.99).According to CO_(2)temperature factors and their relationships,CO_(2)emission factors of other ambien temperatures could be calculated when the CO_(2)emission factor of 23℃was obtained,and the method also could be used to obtain the CO_(2)temperature factors of different vehicles.To separate the effect of load setting and temperature variation on CO_(2)emission quantitatively a method was proposed.And results showed that the load setting was dominant for the CO_(2)emission variation.Compared with 23℃,the CO_(2)emission for vehicle 1 caused by load setting variation were 62.83 and 47.42 g/km,respectively at-10 and 0℃,while those fo vehicle 2 were 45.01 and 35.63 g/km,respectively.展开更多
基金supported by the"Thirteenth Five-Year"Special Project in Military Logistics Scientific Program(AWS16J032)the Innovation Project of Military Medicine(16CXZ017)
文摘The battlefield treatments of spinal and spinal cord injury vary from civilian settings. However, there is no unified battlefield treatment guidelines for spine trauma in PLA. An expert consensus is reached, based on spine trauma epidemiology and the concepts of battlefield treatment combined with the existing levels of military medical care in modern warfare. Since the specialized treatment for spine trauma are no significant difference between civilian settings and modern war, the first aid, emergency treatment and early treatment of spine trauma are introduced separately in three levels in this consensus. In Level I facilities, the fast and accurate evaluation of spine trauma followed by fixation and stabilization are recommended during the first-aid stage. Re-evaluation, further treatment for possible hemorrhagic shock, dyspnea and infection are recommended at Level II facilities. At Level III facilities, it is recommended to strengthen the intensive care and the prevention of urinary system and lung infection for the wounded with severe spinal injury, however, spinal surgery is not recommended in a battlefield hospital. The grading standard for evidence evaluation and recommendation was used to reach this expert consensus.
文摘Various virulence-associated genes or pathogenicity island are responsible for determining the pathogenicity of Escherichia coli strains. However, the correlation of the number and combination patterns of virulence-associated genes in Escherichia coli strains with their pathogenicity remains largely unknown. In this work, 581 chicken Escherichia coli strains were isolated from 1045 liver samples of dead chickens from 50 chicken farms at four provinces in China during 2007-2012. Based on the pathogenic test of SPF chickens, 320 chickens pathogenic Escherichia coli isolates were identified as highly (n = 193), intermediate (n = 98) and low pathogenic (n = 29) strains, respectively. Furthermore, the number of virulence genes in the 320 chicken pathogenic and 50 non-pathogenic Escherichia coli strains was examined. Our results reveal that thirteen virulence genes in Escherichia coli strains were detected, and all strains carried at least two or more than two virulence-associated genes. This study also suggests that highly pathogenic E. coli strains simultaneously carried at least 8 to13 virulence genes while intermediate pathogenic strains carried at least 5 to 8 virulence genes. The number of virulence-associated genes detected in highly pathogenic strains showed there were more significant differences than that in low pathogenic strains (P irp2, fyuA, and colV in high pathogenic strains was significantly higher than that in low and non-pathogenic strains (P irp2, fyuA, iucA, iucD, iutA, papC, iss, tsh, and colV were more often detected in highly and intermediate pathogenic E. coli strains. Taken together, our results provide evidences demonstrating that the pathogenicity of Escherichia coli strains is closely associated with the number and combination patterns of virulence-associated genes.
文摘BACKGROUND A radicular groove is an anatomic malformation that usually initiates at the central fossa,extending along the root at varying lengths and depths and predisposes the involved tooth to a severe periodontal defect.Severe grooves that extend to the root apex often lead to complex combined periodontal-endodontic lesions.They are a serious challenge for doctors to diagnose and treat.CASE SUMMARY In this report,we described a patient with a maxillary lateral incisor with a deep palatogingival groove with two roots,which led to complex combined periodontal-endodontic lesions.Suggested treatment modalities included curettage of the affected tissues,elimination of the groove by grinding and/or sealing with a variety of filling materials,and surgical procedures.In this case,a combination of endodontic therapy,intentional replantation,and root resection were used,which resulted in periodontal/periradicular healing after 12 mo.CONCLUSION Intentional replantation and root resection offer a predictable procedure and should be considered a viable treatment modality for the management of palatogingival grooves,especially for two-rooted teeth.
基金Shanghai Municipal Health and Family Planning Commission Scientific Research Project,Grant/Award Number:20154Y0075Shanghai Municipal Fund for Science and Technology Development,Grant/Award Number:15140904000+1 种基金Shanghai Public Health Clinical Center,Grant/Award Number:KY-GW-2017-04,KY-GW-2018-48National Natural Science Foundation of China,Grant/Award Number:31270217,31601908,81471397
文摘Reporter genes are widely applied in biotechnology and biomedical research owning to their easy observation and lack of toxicity. Taking advantage of the reporter genes in conjunction with imaging technologies, a large number of reporter mouse models have been generated. Reporter mouse models provide systems that enable the studies of live cell imaging, cell lineage tracing, immunological research and cancers etc. in vivo. In this review, we describe the types of different reporter genes and reporter mouse models including, random reporter strains, Cre reporter strains and ROSA26 reporter strains. Collectively, these reporter mouse models have broadened scientific inquires and provided potential strategies for generation of novel reporter animal models with enhanced capabilities.
基金the International S&T Cooperation Program of China project"Research on Informational Project Construction Management based on Open BIM"(Grant No.2011DFG73520)
文摘As the world pays more attention to low-earbon and sustainable development,there's a growing trend in architecture,engineering and construction fields to construct greener,more energy efficient and more sustainable buildings with the help of building information modeling(BIM).As BIM application becomes popular in industry,more and more scholars and engineers point out that an integrated construction environment is better for BIM's fully functional capability.This paper illustrates the relationship between BIM application and an integrated construction environment based on case survey data.It is found that even though an integration construction environment is not necessary in BIM application,the statistical results showed that DBB(design-bid-build)and CM(construction management)modes have great differences in BIM's application implementation scope and implementation deepness,while DB and CM modes do not.
文摘Objective: To explore the effect of thymalfasin on coagulation index, immune function, PCT and sTREM-1 levels in patients with community acquired pneumonia. Methods: 160 patients with community acquired pneumonia admitted in our hospital from June 2016-June 2017 were divided into the control group and the observation group according to the random number table method, each 80 cases. The control group was given conventional treatment, while the observation group was given thymalfasin on the basis of conventional treatment. The levels of D-D, FBG, complement C3, C4, T lymphocyte subsets, PCT and sTREM-1 were detected before and after treatment. Results: Before treatment, there was no statistical difference between the serum levels of D-D, FBG, C3, C4, CD3+,CD4+,CD8+,CD4+/CD8+, PCT and sTREM-1 in the two groups of patients, and P>0.05. After treatment, the levels of CD3+, CD4+and CD4+/CD8+ in the control group and the observation group were significantly increased, and the levels of D-D, FBG, CD8+, PCT and sTREM-1 were significantly decreased, and the level of CD3+, CD4+ and CD4+/CD8+ in the observation group was significantly higher than that of the control group after treatment, and the D-D, FBG, CD8+, PCT and sTREM-1 levels were significantly lower than those in the control group, the difference was statistically significant, P<0.05. Conclusion: Thymalfasin has a certain clinical effect in the treatment of patients with community acquired pneumonia. It can significantly improve the blood coagulation function, enhance the immune ability and alleviate the inflammatory state.
基金the National Nature Science Foundation of China(grant nos.52192610,51973170,12002054,and 52202186)Ministry of Science and Technology of China(grant no.SQ2021YFE010405)+7 种基金Israel Science Foundation and National Natural Sciences Foundation of China Bilateral grant(grant no.3145/19)Ministry of Science and Technology of Israel project(grant no.3-18130)the China-Israel Cooperative Scientific Research,Fundamental Research Funds for the Central Universities(grant no.ZDRC2205)Fundamental Research Funds for the Central Universities(grant no.JC2107)Natural Science Foundation of Shaanxi Province(grant nos.2019JCW-17 and 2020JCW-15)Development and Planning Guide Foundation of Xidian University(grant no.21103200005)Fundamental Research Funds for the Central Universities(grant no.JC2107)State Scholarship Fund of China Scholarship Council(grant no.202006960032).
文摘Hydrogen bonds are non-covalent interactions and essential for assembling supermolecules into ordered structures in biological systems,endowing crystals with fascinating physical properties,and inspiring the construction of eco-friendly electromechanical devices.However,the interplay between hydrogen bonding and the physical properties is not fully understood at the molecular level.Herein,we demonstrate that the physical property of biological crystals with double-layer structures could be enhanced by rationally controlling hydrogen bonding interactions between amino and carboxyl groups.Different hydrogen bonding interactions result in various thermal,mechanical,electronic,and piezoelectric properties.In particular,the weak interaction between O and H atoms contributes to low mechanical strength that permits important ion displacement under stress,giving rise to a strong piezoelectric response.This study not only reveals the correlation between the hydrogen bonding and physical properties in double-layer structures of biological crystals but also demonstrates the potential of these crystals as functional biomaterials for high-performance energy-harvesting devices.Theoretical calculations and experimental verifications in this work provide new insights into the rational design of biomaterials with desirable physical properties for bioelectrical devices by modulating intermolecular interactions.
基金This article was sponsored by Medical Research Foundation of Chongqing,China(2019MSXM034).
文摘Purpose::To investigate the clinical value of urine interleukin-18(IL-8),neutrophil gelatinase-associated lipocalin(NGAL)and kidney injury molecule-1(KIM-1)for the early diagnosis of acute kidney injury(AKI)in patients with ureteroscopic lithotripsy(URL)related urosepsis.Methods::A retrospective study was carried out in 157 patients with urosepsis after URL.The patients were divided into AKI group and non-AKI group according to the Kidigo guideline and urine IL-8,NGAL and KIM-1 levels were detected by enzyme-linked immunosorbent assay at 0,4,12,24 and 48 h after the surgery.Receiver operating characteristic curve(ROC)was used to evaluate the diagnostic value of these three biomarkers for postoperative AKI.Results::The level of urine IL-8,NGAL and KIM-1 in AKI group was significantly higher than that in non-AKI group at 4,12,24 and 48 h(p<0.01).The ROC analysis showed the combined detection of urine IL-8,NGAL and KIM-1 at 12 h had a larger area under curve(AUC)than a single marker(0.997,95%CI:0.991-0.998),and the sensitivity and specificity were 98.2%and 96.7%,respectively.Pearson correlation analysis showed that the levels of urine NGAL at 4,12,24 and 48 h in AKI patients were positively correlated with the levels of urine KIM-1 and IL-18(p<0.01).Conclusion::AKI could be quickly recognized by the elevated level of urine IL-8,NGAL and KIM-1 in patients with URL-related urosepsis.Combined detection of the three urine biomarkers at 12 h after surgery had a better diagnostic performance,which may be an important reference for the early diagnosis of AKI.
基金We thank staff members Biomedical Core Facility, Fudan University and National Center for Protein Science Shanghai for their help on Mass Spectrometry analyses. We thank the Tsinghua Cryo-EM Facility and High Performance Computation Facility of National Center for Protein Science Beijing for their support in cryo-EM data collection and processing. This work was supported by Grants from the National Natural Science Foundation of China (Grant Nos. U1432242, 31425008, 91419301), Basic Research Project of Shanghai Science and Technology Commission (No. 12JC1402700), the Program of Shanghai Subject Chief Scientist (,No. 14XD1400500).
基金Strategic Priority Research Program of Chinese Academy of Sciences(XDB08010203)National Key R&D Program of China(2017YFA0504600)the National Natural Science Foundation of China(Grant Nos.31430024,91540201 and 31325007).
文摘Assembly of eukaryotic ribosome is a complicated and dynamic process that involves a series of intermediates.It is unknown how the highly intertwined structure of 60S large ribosomal subunits is established.Here,we report the structure of an early nucleolar pre-60S ribosome determined by cryo-electron microscopy at 3.7 A resolution,revealing a half-assembled subunit.DomainsⅠ,ⅡandⅣof 25S/5.8S rRNA pack tightly into a native-like substructure,but domains Ⅲ,ⅣandⅤare not assembled.The structure contains 12 assembly factors and 19 ribosomal proteins,many of which are required for early processing of large subunit rRNA.The Brx1-Ebp2 complex would interfere with the assembly of domains Ⅳ and Ⅴ.Rpf1,Mak16,Nsa1 and Rrp1 form a cluster that consolidates the joining of domainsⅠandⅡ.Our structure reveals a key intermediate on the path to establishing the global architecture of 60S subunits.
基金supported by the National Natural Science Foundation of China(No.52172337)the National Engineering Laboratory for Mobile Source Emission Control Technology(No.NELMS2018A17)the National Key Research and Development Project of China(No.2018YFE0106800-001)。
文摘Because of global warming,people have paid more attention to greenhouse gas emitted by vehicles.To quantify the impact of temperature on vehicle CO_(2)emissions,this study was conducted using the world light vehicle test cycle on two light-duty E10 gasoline vehicles a ambient temperatures of-10,0,23,and 40℃,and found that CO_(2)emission factors of Vehicle1 in the low-speed phase were 22.07%and 20.22%higher than those of Vehicle 2 at cold star and hot start under-10℃.The reason was vehicle 1 had a larger displacement and more friction pairs than vehicle 2.There was the highest CO_(2)emission at the low-speed phase due to low average speed,frequent acceleration,and deceleration.The CO_(2)temperature factor and the ambient temperature had a strong linear correlation(R2=0.99).According to CO_(2)temperature factors and their relationships,CO_(2)emission factors of other ambien temperatures could be calculated when the CO_(2)emission factor of 23℃was obtained,and the method also could be used to obtain the CO_(2)temperature factors of different vehicles.To separate the effect of load setting and temperature variation on CO_(2)emission quantitatively a method was proposed.And results showed that the load setting was dominant for the CO_(2)emission variation.Compared with 23℃,the CO_(2)emission for vehicle 1 caused by load setting variation were 62.83 and 47.42 g/km,respectively at-10 and 0℃,while those fo vehicle 2 were 45.01 and 35.63 g/km,respectively.