Composite analyses were performed in this study to reveal the difference in spring precipitation over southern China during multiyear La Ni?a events during 1901 to 2015. It was found that there is significantly below-...Composite analyses were performed in this study to reveal the difference in spring precipitation over southern China during multiyear La Ni?a events during 1901 to 2015. It was found that there is significantly below-normal precipitation during the first boreal spring, but above-normal precipitation during the second year. The difference in spring precipitation over southern China is correlative to the variation in western North Pacific anomalous cyclone(WNPC), which can in turn be attributed to the different sea surface temperature anomaly(SSTA) over the Tropical Pacific. The remote forcing of negative SSTA in the equatorial central and eastern Pacific and the local air-sea interaction in the western North Pacific are the usual causes of WNPC formation and maintenance.SSTA in the first spring is stronger than those in the second spring. As a result, the intensity of WNPC in the first year is stronger, which is more likely to reduce the moisture in southern China by changing the moisture transport, leading to prolonged precipitation deficits over southern China. However, the tropical SSTA signals in the second year are too weak to induce the formation and maintenance of WNPC and the below-normal precipitation over southern China. Thus, the variation in tropical SSTA signals between two consecutive springs during multiyear La Ni?a events leads to obvious differences in the spatial pattern of precipitation anomaly in southern China by causing the different WNPC response.展开更多
The Agulhas system is the strongest western boundary current system in the Southern Hemisphere and plays an important role in modulating the Indian-to-Atlantic Ocean water exchange by the Agulhas leakage.It is difficu...The Agulhas system is the strongest western boundary current system in the Southern Hemisphere and plays an important role in modulating the Indian-to-Atlantic Ocean water exchange by the Agulhas leakage.It is difficult to measure in situ transport of the Agulhas leakage as well as the Agulhas retroflection position due to their intermittent nature.In this study,an innovative kinematic algorithm was designed and applied to the gridded altimeter observational data,to ascertain the longitudinal position of Agulhas retroflection,the stability of Agulhas jet stream,as well as its strength.The results show that the east-west shift of retroflection is related neither to the strength of Agulhas current nor to its stability.Further analysis uncovers the connection between the westward extension of Agulhas jet stream and an anomalous cyclonic circulation at its northern side,which is likely attributed to the local wind stress curl anomaly.To confirm the effect of local wind forcing on the east-west shift of retroflection,numerical sensitivity experiments were conducted.The results show that the local wind stress can induce a similar longitudinal shift of the retroflection as altimetry observations.Further statistical and case study indicates that whether an Agulhas ring can continuously migrate westward to the Atlantic Ocean or re-merge into the main flow depends on the retroflection position.Therefore,the westward retroflection may contribute to a stronger Agulhas leakage than the eastward retroflection.展开更多
AIM： To study the expression of the inhibitor of apoptosis protein survivin in hepatocellular carcinoma （HCC）, and its correlation with clinicopathological factors, cell proliferation, recurrence and prognosis afte...AIM： To study the expression of the inhibitor of apoptosis protein survivin in hepatocellular carcinoma （HCC）, and its correlation with clinicopathological factors, cell proliferation, recurrence and prognosis after hepatectomy. METHODS： Immunohistochemical staining of survivin and Ki-67 was performed by the standard streptavidin- peroxidase technique on paraffin sections of 55 cases of HCC. RESULTS： The positive rate of survivin in HCC was 52.7% （29/55）. Significant correlation was found between survivin expression with portal vein thrombi and intrahepatic matastasistic nodes （P 〈 0.05）. The recurrent rate in survivin-positive HCC was significantly higher than that in survivin-negative HCC after hepatectomy, the 1- and 3-year survival rate in patients with survivin-positive tumors was significantly lower than that in patients with survivin-negative tumors （58.62 and 10.34% vs 76.92 and 30.77%, P 〈 0.05, log-rank test）. The proliferation index （Ki-67） in survivin-positive HCC （33.83% ± 18.90%） was significantly higher than that in survivin-negative HCC （19.60% ± 19.35%） （P 〈 0.05）. CONCLUSION： Survivin may play an important role in progression of HCC by promoting cell proliferation, and may be positively correlated with high risk of disease recurrence and poor prognosis in HCC. Its expression may serve as a prognostic factor for patients with HCC after hepatectomy.展开更多
The second-generation Global Ocean Data Assimilation System of the Beijing Climate Center （BCC_GODAS2.0） has been run daily in a pre-operational mode. It spans the period 1990 to the present day. The goal of this pa...The second-generation Global Ocean Data Assimilation System of the Beijing Climate Center （BCC_GODAS2.0） has been run daily in a pre-operational mode. It spans the period 1990 to the present day. The goal of this paper is to introduce the main components and to evaluate BCC_GODAS2.0 for the user community. BCC_GODAS2.0 consists of an observational data preprocess, ocean data quality control system, a three-dimensional variational （3DVAR） data assimilation, and global ocean circulation model [Modular Ocean Model 4 （MOM4）]. MOM4 is driven by six-hourly fluxes from the National Centers for Environmental Prediction. Satellite altimetry data, SST, and in-situ temperature and salinity data are assimilated in real time. The monthly results from the BCC_GODAS2.0 reanalysis are compared and assessed with observations for 1990-201 I. The climatology of the mixed layer depth of BCC_GODAS2.0 is generally in agreement with that of World Ocean Atlas 2001. The modeled sea level variations in the tropical Pacific are consistent with observations from satellite altimetry on interannual to decadal time scales. Performances in predicting variations in the SST using BCC_GODAS2.0 are evaluated. The standard deviation of the SST in BCC_GODAS2.0 agrees well with observations in the tropical Pacific. BCC_GODAS2.0 is able to capture the main features of E1 Nifio Modoki I and Modoki II, which have different impacts on rainfall in southern China. In addition, the relationships between the Indian Ocean and the two types of E1 Nino Modoki are also reproduced.展开更多
Objective: To compare efficacy of therapy scheme as Transhepatic Artery Chemoembolization (TACE) + Radiofrequency Ablation (RFA) + Introportal Vein Chemotherapy (PVC) + Percutaneous Ethanol Injection (PEI) therapy (qu...Objective: To compare efficacy of therapy scheme as Transhepatic Artery Chemoembolization (TACE) + Radiofrequency Ablation (RFA) + Introportal Vein Chemotherapy (PVC) + Percutaneous Ethanol Injection (PEI) therapy (quadruplet group) with TACE + RFA combinational therapy (diad group) in treating hepatocellular carcinoma (HCC). Methods: 25 cases in quadruplet group were treated by TACE for 3 weeks, then by RFA, after 2 months, by PVC + PEI;23 cases in diad group were treated by TACE for 3 weeks and then by PEI. After completion of each treatment course in both groups, Alphafetoprotein (AFP) was tested 2 months later;abdomen colorful doppler, CT and AFP were retested 6 months later. Results: AFP was significantly decreased in 23 cases of quadruplet group and 20 cases of diad group among those with AFP positive results. 6 months later, examinations of CT, colorful Doppler and AFP in two groups showed: quadruplet group has significantly decreased (X2 = 6.81, P 0.01) blood supply of cancer tissue and significantly diminished (X2 = 8.29, P 0.01) tumor size, few cases with AFP elevation (X2 = 5.06, P 0.05);lower 1 year relapse rate and two years mortality than that in diad group (X2 = 5.30, P 0.05). Conclusion: TACE + RFA + PVC + PEI combinational therapy is a safe double intervention treatment for HCC scheme with less side effects, which is better than TACE + PEI scheme in killing remnant tumor and reducing relapse.展开更多
Chemoenzymatic catalysis can give full play to the advantages of versatile reactivity of chemocatalysis and excellent chemo-,regio-,and stereoselectivities of biocatalysis.These chemoenzymatic methods can not only sav...Chemoenzymatic catalysis can give full play to the advantages of versatile reactivity of chemocatalysis and excellent chemo-,regio-,and stereoselectivities of biocatalysis.These chemoenzymatic methods can not only save resource,cost,and operating time but also reduce the number of reaction steps,and avoid separating unstable intermediates,leading to the generation of more products under greener circumstances and thereby playing an indispensable role in the fields of medicine,materials and fine chemicals.Although incompatible challenges between chemocatalyst and biocatalyst remain,strategies such as biphasic system,artificial metalloenzymes,immobilization or supramolecular host,and protein engineering have been designed to overcome these issues.In this review,chemoenzymatic catalysis according to different chemocatalysis types was classifiably described,and in particular,the classic dynamic kinetic resolutions(DKR)and cofactor regeneration were summarized.Finally,the bottlenecks and development of chemoenzymatic catalysis were summarized,and future development was prospected.展开更多
Parkinson’s disease(PD)is a very common neurodegenerative disease that occurs mostly in the elderly.There are many main clinical manifestations of PD,such as tremor,bradykinesia,muscle rigidity,etc.Based on the curre...Parkinson’s disease(PD)is a very common neurodegenerative disease that occurs mostly in the elderly.There are many main clinical manifestations of PD,such as tremor,bradykinesia,muscle rigidity,etc.Based on the current research on PD,the accurate and convenient detection of early symptoms is the key to detect PD.With the development of microelectronic and sensor technology,it is much easier to measure the barely noticeable tremor in just one hand for the early detection of Parkinson’s disease.In this paper,we present a smart wearable device for detecting hand tremor,in which MPU6050(MIDI Processing Unit)consisting of a 3-axis gyroscope and a 3-axis accelerometer is used to collect acceleration and angular velocity of fingers.By analyzing the time of specific finger movements,we successfully recognized the tremor signals with high accuracy.Meanwhile,with Bluetooth 4.0(Bluetooth Low Energy,BLE)and networking terminal ability,tremor data can be transferred to a monitoring device in real time with extremely lowenergy consumption.The experimental results have shown that the proposed device(smart ring)is convenient for long-term tremor detection which is vital for early detection and treatment for Parkinson’s disease.展开更多
The scale factor of a superconducting gravimeter(SG) is usually calibrated by using simultaneous and co-located gravity measurements with the FG5-type absolute gravimeter(AG). In this paper, another new kind of absolu...The scale factor of a superconducting gravimeter(SG) is usually calibrated by using simultaneous and co-located gravity measurements with the FG5-type absolute gravimeter(AG). In this paper, another new kind of absolute gravimetercold atom gravimeter(CAG) is first reported to calibrate the SG. Five-day side-by-side gravity measurements have been carried out by using our CAG(NIM-AGRb-1) to calibrate the SG(iGrav-012) located at Changping Campus of the National Institute of Metrology(NIM) of China. A weighted least-squares method is applied to determine the scale factor and the result is given as(-928.01 ± 0.73) nm·s^(-2)·V^(-1) with a precision of 0.79‰. We have demonstrated that a calibration precision of 1‰ level can be achieved after 3 days of parallel observations at spring tide. The obtained calibration results are then compared with the previous calibration by FG5 X-249, which shows that the calibration precision obtained by using NIM-AGRb-1 was slightly higher than FG5 X-249 with the same time interval. The factors affecting the calibration precision are analyzed in the calibrations by means of different AGs. Finally, several calibration experiments for SG iGrav-012 are discussed. The final scale factor is estimated as(-927.58 ± 0.36) nm·s^(-2)·V^(-1) with an accuracy of 0.39‰. Our main results demonstrate that the CAGs can be used for high-precision calibrations of SGs.展开更多
Objective: To understand the crucial role of the klotho gene in hearing development in mouse models.Methods: PCR was used to identify CBA mice with different genotypes, i.e. WT, heterozygous(klotho +/-)or homozygous(k...Objective: To understand the crucial role of the klotho gene in hearing development in mouse models.Methods: PCR was used to identify CBA mice with different genotypes, i.e. WT, heterozygous(klotho +/-)or homozygous(klotho-/-). Mice phenotype and weight were recorded postnatal 25 days(P-25) and auditory brainstem responses(ABR) were used to determine auditory function at P-60.Results: klotho-/-mice tended to have smaller size, lighter weight and higher ABR thresholds at P-60,showing early onset age-related hearing loss(ARHL).Conclusion: Heterozygous and homozygous klotho deficient mice exhibit different degrees of hearing loss at young age, with homozygous mice(klotho-/-) showing more severe hearing loss. Our results indicate that persisted expression of klotho protein in the inner ear may potentially delay the onset of ARHL and play an important role in the protection of auditory function.展开更多
基金The National Natural Science Foundation of China under contract Nos 41576029, 41976221 and 42030410the National Key Research and Development Program of China under contract No. 2019YFA0606702the Startup Foundation for Introducing Talent of Nanjing University of Information Science and Technology。
文摘Composite analyses were performed in this study to reveal the difference in spring precipitation over southern China during multiyear La Ni?a events during 1901 to 2015. It was found that there is significantly below-normal precipitation during the first boreal spring, but above-normal precipitation during the second year. The difference in spring precipitation over southern China is correlative to the variation in western North Pacific anomalous cyclone(WNPC), which can in turn be attributed to the different sea surface temperature anomaly(SSTA) over the Tropical Pacific. The remote forcing of negative SSTA in the equatorial central and eastern Pacific and the local air-sea interaction in the western North Pacific are the usual causes of WNPC formation and maintenance.SSTA in the first spring is stronger than those in the second spring. As a result, the intensity of WNPC in the first year is stronger, which is more likely to reduce the moisture in southern China by changing the moisture transport, leading to prolonged precipitation deficits over southern China. However, the tropical SSTA signals in the second year are too weak to induce the formation and maintenance of WNPC and the below-normal precipitation over southern China. Thus, the variation in tropical SSTA signals between two consecutive springs during multiyear La Ni?a events leads to obvious differences in the spatial pattern of precipitation anomaly in southern China by causing the different WNPC response.
基金The National Key R&D Program of China under contract No.2019YFA0606702the National Natural Science Foundation of China under contract Nos 42176222,91858202,41630963,and 41776003+1 种基金the National Science Foundation under contract No.NSF-IIS-2123264the fund suported by the National Aeronautics and Space Administration under contract No.NASA-80NSSC20M0220.
文摘The Agulhas system is the strongest western boundary current system in the Southern Hemisphere and plays an important role in modulating the Indian-to-Atlantic Ocean water exchange by the Agulhas leakage.It is difficult to measure in situ transport of the Agulhas leakage as well as the Agulhas retroflection position due to their intermittent nature.In this study,an innovative kinematic algorithm was designed and applied to the gridded altimeter observational data,to ascertain the longitudinal position of Agulhas retroflection,the stability of Agulhas jet stream,as well as its strength.The results show that the east-west shift of retroflection is related neither to the strength of Agulhas current nor to its stability.Further analysis uncovers the connection between the westward extension of Agulhas jet stream and an anomalous cyclonic circulation at its northern side,which is likely attributed to the local wind stress curl anomaly.To confirm the effect of local wind forcing on the east-west shift of retroflection,numerical sensitivity experiments were conducted.The results show that the local wind stress can induce a similar longitudinal shift of the retroflection as altimetry observations.Further statistical and case study indicates that whether an Agulhas ring can continuously migrate westward to the Atlantic Ocean or re-merge into the main flow depends on the retroflection position.Therefore,the westward retroflection may contribute to a stronger Agulhas leakage than the eastward retroflection.
文摘AIM： To study the expression of the inhibitor of apoptosis protein survivin in hepatocellular carcinoma （HCC）, and its correlation with clinicopathological factors, cell proliferation, recurrence and prognosis after hepatectomy. METHODS： Immunohistochemical staining of survivin and Ki-67 was performed by the standard streptavidin- peroxidase technique on paraffin sections of 55 cases of HCC. RESULTS： The positive rate of survivin in HCC was 52.7% （29/55）. Significant correlation was found between survivin expression with portal vein thrombi and intrahepatic matastasistic nodes （P 〈 0.05）. The recurrent rate in survivin-positive HCC was significantly higher than that in survivin-negative HCC after hepatectomy, the 1- and 3-year survival rate in patients with survivin-positive tumors was significantly lower than that in patients with survivin-negative tumors （58.62 and 10.34% vs 76.92 and 30.77%, P 〈 0.05, log-rank test）. The proliferation index （Ki-67） in survivin-positive HCC （33.83% ± 18.90%） was significantly higher than that in survivin-negative HCC （19.60% ± 19.35%） （P 〈 0.05）. CONCLUSION： Survivin may play an important role in progression of HCC by promoting cell proliferation, and may be positively correlated with high risk of disease recurrence and poor prognosis in HCC. Its expression may serve as a prognostic factor for patients with HCC after hepatectomy.
基金supported by the National Natural Science Foundation of China (Grant No. 41306005)the National Basic Research Program of China (Grant No. 2012CB955903)the CAS/SAFEA International Partnership Program for Creative Research Teams
文摘The second-generation Global Ocean Data Assimilation System of the Beijing Climate Center （BCC_GODAS2.0） has been run daily in a pre-operational mode. It spans the period 1990 to the present day. The goal of this paper is to introduce the main components and to evaluate BCC_GODAS2.0 for the user community. BCC_GODAS2.0 consists of an observational data preprocess, ocean data quality control system, a three-dimensional variational （3DVAR） data assimilation, and global ocean circulation model [Modular Ocean Model 4 （MOM4）]. MOM4 is driven by six-hourly fluxes from the National Centers for Environmental Prediction. Satellite altimetry data, SST, and in-situ temperature and salinity data are assimilated in real time. The monthly results from the BCC_GODAS2.0 reanalysis are compared and assessed with observations for 1990-201 I. The climatology of the mixed layer depth of BCC_GODAS2.0 is generally in agreement with that of World Ocean Atlas 2001. The modeled sea level variations in the tropical Pacific are consistent with observations from satellite altimetry on interannual to decadal time scales. Performances in predicting variations in the SST using BCC_GODAS2.0 are evaluated. The standard deviation of the SST in BCC_GODAS2.0 agrees well with observations in the tropical Pacific. BCC_GODAS2.0 is able to capture the main features of E1 Nifio Modoki I and Modoki II, which have different impacts on rainfall in southern China. In addition, the relationships between the Indian Ocean and the two types of E1 Nino Modoki are also reproduced.
文摘Objective: To compare efficacy of therapy scheme as Transhepatic Artery Chemoembolization (TACE) + Radiofrequency Ablation (RFA) + Introportal Vein Chemotherapy (PVC) + Percutaneous Ethanol Injection (PEI) therapy (quadruplet group) with TACE + RFA combinational therapy (diad group) in treating hepatocellular carcinoma (HCC). Methods: 25 cases in quadruplet group were treated by TACE for 3 weeks, then by RFA, after 2 months, by PVC + PEI;23 cases in diad group were treated by TACE for 3 weeks and then by PEI. After completion of each treatment course in both groups, Alphafetoprotein (AFP) was tested 2 months later;abdomen colorful doppler, CT and AFP were retested 6 months later. Results: AFP was significantly decreased in 23 cases of quadruplet group and 20 cases of diad group among those with AFP positive results. 6 months later, examinations of CT, colorful Doppler and AFP in two groups showed: quadruplet group has significantly decreased (X2 = 6.81, P 0.01) blood supply of cancer tissue and significantly diminished (X2 = 8.29, P 0.01) tumor size, few cases with AFP elevation (X2 = 5.06, P 0.05);lower 1 year relapse rate and two years mortality than that in diad group (X2 = 5.30, P 0.05). Conclusion: TACE + RFA + PVC + PEI combinational therapy is a safe double intervention treatment for HCC scheme with less side effects, which is better than TACE + PEI scheme in killing remnant tumor and reducing relapse.
基金The authors thank the financial support by National Natural Science Foundation of China(21776132,21878142)Jiangsu Province Natural Science Foundation for Distinguished Young Scholars(BK20190035)+2 种基金National Key Research and Development Program of China(2019YFD1101202)Jiangsu Province Natural Science Foundation for Youths(BK20200685)China Postdoctoral Science Foundation(2019M660113).
文摘Chemoenzymatic catalysis can give full play to the advantages of versatile reactivity of chemocatalysis and excellent chemo-,regio-,and stereoselectivities of biocatalysis.These chemoenzymatic methods can not only save resource,cost,and operating time but also reduce the number of reaction steps,and avoid separating unstable intermediates,leading to the generation of more products under greener circumstances and thereby playing an indispensable role in the fields of medicine,materials and fine chemicals.Although incompatible challenges between chemocatalyst and biocatalyst remain,strategies such as biphasic system,artificial metalloenzymes,immobilization or supramolecular host,and protein engineering have been designed to overcome these issues.In this review,chemoenzymatic catalysis according to different chemocatalysis types was classifiably described,and in particular,the classic dynamic kinetic resolutions(DKR)and cofactor regeneration were summarized.Finally,the bottlenecks and development of chemoenzymatic catalysis were summarized,and future development was prospected.
基金supported by the National Natural Science Foundation of China(Grant Nos.61972207 and 61802196)Jiangsu Provincial Government Scholarship for Studying Abroad and the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)fund.
文摘Parkinson’s disease(PD)is a very common neurodegenerative disease that occurs mostly in the elderly.There are many main clinical manifestations of PD,such as tremor,bradykinesia,muscle rigidity,etc.Based on the current research on PD,the accurate and convenient detection of early symptoms is the key to detect PD.With the development of microelectronic and sensor technology,it is much easier to measure the barely noticeable tremor in just one hand for the early detection of Parkinson’s disease.In this paper,we present a smart wearable device for detecting hand tremor,in which MPU6050(MIDI Processing Unit)consisting of a 3-axis gyroscope and a 3-axis accelerometer is used to collect acceleration and angular velocity of fingers.By analyzing the time of specific finger movements,we successfully recognized the tremor signals with high accuracy.Meanwhile,with Bluetooth 4.0(Bluetooth Low Energy,BLE)and networking terminal ability,tremor data can be transferred to a monitoring device in real time with extremely lowenergy consumption.The experimental results have shown that the proposed device(smart ring)is convenient for long-term tremor detection which is vital for early detection and treatment for Parkinson’s disease.
基金Project supported by the National Key Research and Development Program of China(Grant Nos.2016YFF0200103 and 2016YFF0200200)the Fundamental Research Funds for National Institute of Metrology,China(Grant No.22-AKY1608)
文摘The scale factor of a superconducting gravimeter(SG) is usually calibrated by using simultaneous and co-located gravity measurements with the FG5-type absolute gravimeter(AG). In this paper, another new kind of absolute gravimetercold atom gravimeter(CAG) is first reported to calibrate the SG. Five-day side-by-side gravity measurements have been carried out by using our CAG(NIM-AGRb-1) to calibrate the SG(iGrav-012) located at Changping Campus of the National Institute of Metrology(NIM) of China. A weighted least-squares method is applied to determine the scale factor and the result is given as(-928.01 ± 0.73) nm·s^(-2)·V^(-1) with a precision of 0.79‰. We have demonstrated that a calibration precision of 1‰ level can be achieved after 3 days of parallel observations at spring tide. The obtained calibration results are then compared with the previous calibration by FG5 X-249, which shows that the calibration precision obtained by using NIM-AGRb-1 was slightly higher than FG5 X-249 with the same time interval. The factors affecting the calibration precision are analyzed in the calibrations by means of different AGs. Finally, several calibration experiments for SG iGrav-012 are discussed. The final scale factor is estimated as(-927.58 ± 0.36) nm·s^(-2)·V^(-1) with an accuracy of 0.39‰. Our main results demonstrate that the CAGs can be used for high-precision calibrations of SGs.
基金supported by the National Nature Science Foundation of China(81470684,21405130)Postdoctoral Science Foundation of China (2015M571818)+5 种基金Clinical Special Fund of Jiangsu Province (b12014032)Six Major Categories Talent (2014WSN-043,2011-WS-074)Jiangsu Provincial University Fund (16621632)Innovation and Entrepreneurship Training Program for College Students in Jiangsu Province (KYLX14-1455,201610313002Z)Colleges and universities Foundation in Jiangsu Province(16621632,16KJB320016)Nature Science planning Foundation of Xuzhou (KC17087)
文摘Objective: To understand the crucial role of the klotho gene in hearing development in mouse models.Methods: PCR was used to identify CBA mice with different genotypes, i.e. WT, heterozygous(klotho +/-)or homozygous(klotho-/-). Mice phenotype and weight were recorded postnatal 25 days(P-25) and auditory brainstem responses(ABR) were used to determine auditory function at P-60.Results: klotho-/-mice tended to have smaller size, lighter weight and higher ABR thresholds at P-60,showing early onset age-related hearing loss(ARHL).Conclusion: Heterozygous and homozygous klotho deficient mice exhibit different degrees of hearing loss at young age, with homozygous mice(klotho-/-) showing more severe hearing loss. Our results indicate that persisted expression of klotho protein in the inner ear may potentially delay the onset of ARHL and play an important role in the protection of auditory function.
