By using the one-point correlation method, calculations have been made of the northern early summer 500 hPa teleconnection patterns. Seven teleconnection patterns are revealed, namely, the Western Atlantic (WA), the E...By using the one-point correlation method, calculations have been made of the northern early summer 500 hPa teleconnection patterns. Seven teleconnection patterns are revealed, namely, the Western Atlantic (WA), the Eastern Atlantic (EA), the Eurasian (EU), the Bengal / Northern Pacific (BNP), the Western Pacific (WP), the East Asian / Pacific (EAP), and the Huanghe / East Asian (HEA) patterns. Their centers are determined and their yearly intensity indices (1951-1990) are calculated. On this basis the relationship between their interannual variations and the drought / flood in China is examined. It is noted that the EU, HEA and EAP wave trains are closely related to the drought / flood in China. The HEA and EAP patterns strongly influence the precipitation in eastern China. For example, the fierce floods experienced in 1991 early summer over China are related to the weak EAP and strong HEA patterns.展开更多
On the basis of the data of zooplankton biomass and three major taxa—— Copepoda, Chaetognatha andSiphonophora of May-June 1986, July-August and December 1987, the distributional patterns and the indicator species of...On the basis of the data of zooplankton biomass and three major taxa—— Copepoda, Chaetognatha andSiphonophora of May-June 1986, July-August and December 1987, the distributional patterns and the indicator species of zooplankton in the Kuroshio and adjacent waters of the East China Sea are preliminarily studied. The results are as follows:The horizontal distribution of zooplankton biomass and the abundance of copepods, chaetognaths and siphonophores arecurred in the continent area northwest of Taiwan and the south-centre section of the East China Sea continent, which are the mix front of different waters. Zooplankton in the water area inside of Ryukyu Islands presented low abundance and high diversity. There are clear seasonal variations in zooplankton biomass and abundance in the study area. The strength or weakness of different water masses and fronts is the basic reason for the variations of zooplankton biomass and abundance.The species composition of zooplankton in the study area is complex and varies, however, the tropic oceanic species predominates overwhelmingly. The distribution of different ecotype species evidences the distribution of different water masses and the state of mixture. The indicator species of each water mass are listed in the paper so as to provide grounds for the variation of currents in the Kuroshio area.The temperature and salinity of sea water are important factors affecting zooplankton distribution, composition and diversity , however the role of salinity is major. With the replacement of one season by another, the correlative levels of temperature and salinity to various zooplankton taxa are more or less significant.展开更多
A water model and a high-speed video camera were utilized in the 300-t RH equipment to study the effect of steel flow patterns in a vacuum chamber on fast decarburization and a superior flow-pattern map was obtained d...A water model and a high-speed video camera were utilized in the 300-t RH equipment to study the effect of steel flow patterns in a vacuum chamber on fast decarburization and a superior flow-pattern map was obtained during the practical RH process. There are three flow patterns with different bubbling characteristics and steel surface states in the vacuum chamber: boiling pattern(BP), transition pattern(TP), and wave pattern(WP). The effect of the liquid-steel level and the residence time of the steel in the chamber on flow patterns and decarburization reaction were investigated, respectively. The liquid-steel level significantly affected the flow-pattern transition from BP to WP, and the residence time and reaction area were crucial to evaluate the whole decarburization process rather than the circulation flow rate and mixing time. A superior flow-pattern map during the practical RH process showed that the steel flow pattern changed from BP to TP quickly, and then remained as TP until the end of decarburization.展开更多
OBJECTIVE: To study the sonographic features and patterns of cystic renal carcinomas. METHODS: Thirteen cases of cystic renal carcinoma confirmed by operation and pathology were examined by ultrasonography, and the cy...OBJECTIVE: To study the sonographic features and patterns of cystic renal carcinomas. METHODS: Thirteen cases of cystic renal carcinoma confirmed by operation and pathology were examined by ultrasonography, and the cystic walls, septa and solid mural nodules were studied. RESULTS: Solid mural nodules of some cases and irregular thickening of the cystic walls and septa were characteristic findings for the ultrasonic diagnosis of cystic renal carcinomas. According to their pathologic mechanisms and sonographic features, cystic renal carcinomas were classified into 3 patterns: unilocular cystic mass, multiloculated cystic mass and cystic-solid mass. CONCLUSIONS: Typical cystic renal carcinomas can be well diagnosed, while atypical cases may be misdiagnosed as benign renal cysts by ultrasonography. Color Doppler ultrasonography and needle aspiration guided by ultrasonography are helpful in the diagnosis of these atypical cases.展开更多
Molecular dynamics simulations are performed to study the nanoindentation models of monolayer suspended graphene and graphyne. Fullerenes are selected as indenters. Our results show that Young's modulus of monolayer-...Molecular dynamics simulations are performed to study the nanoindentation models of monolayer suspended graphene and graphyne. Fullerenes are selected as indenters. Our results show that Young's modulus of monolayer-thick graphyne is almost half of that of graphene, which is estimated to be 0.50 TPa. The mechanical properties of graphene and graphyne are different in the presence of strain. A pre-tension has an important effect on the mechanical properties of a membrane. Both the pre-tension and Young's modulus plots demonstrate index behavior. The toughness of graphyne is stronger than that of graphene due to Young's modulus magnitude. Young's moduli of graphene and graphyne are almost independent of the size ratio of indenter to membrane.展开更多
Two body centered tetragonal (bet) crystal structures of α'-Fe_(16)N_2 with x=0.25, z=0.3125 (Jack-1) and x=0.222, z=0.306 (Jack-2) respectively, were analyzed theoretically with EMS software package. The simulat...Two body centered tetragonal (bet) crystal structures of α'-Fe_(16)N_2 with x=0.25, z=0.3125 (Jack-1) and x=0.222, z=0.306 (Jack-2) respectively, were analyzed theoretically with EMS software package. The simulation of diffraction patterns indicates that both diffraction patterns of the same axis in these two structures obey bcc extinction rule. The conclusion is also obtained from the analyses of the diffracted waves. α'-Fe_(16)N_2 precipitates in the diffusion layer of ion-nitrided α-iron have been studied with transmission electron microscope (TEM). We have distinctly observed the electron diffraction patterns of α'-Fe_(16)N_2 in [100], [111], [110], [011], [210], [021], [311], [113], [331] and [133] zone axes with perfect symmetry, which indicate the parallel orientation relationship with α matrix:<001>α'//<001>α'// {100}.α'// {100}tα. The analyses of diffraction patterns, which obey bcc extinction rule, verify the bct structure of α'-Fe_(16)N_2 discovered by X-ray diffraction.展开更多
We studied a new grain-cash cropping pattern composed of "barley/watermelon + waize-rice", comparing with "barley / watermelon-rice" (CKI), "watermelon-rice", (CK2). The experiment was co...We studied a new grain-cash cropping pattern composed of "barley/watermelon + waize-rice", comparing with "barley / watermelon-rice" (CKI), "watermelon-rice", (CK2). The experiment was conducted in CNRRI’s field for 3 yr, employing completely randomized design with three replications, and each plot occupied 207 m~2. The soil in the experiment field contained: N, 2.48 g. kg, quick effective P 4 mg. kg, and quick effective K 53 mg·kg. The varieties tested were Zhemai 2 (barley), Zhemi 1 (watermelon), Suyu 1 (maize), and Shanyou 63 (hybrid rice).展开更多
Change in Arctic sea ice extent is one of the indicators of global climate changes. Spatio-temporal change and change patterns can be identified using various methods to facilitate human understanding global climate c...Change in Arctic sea ice extent is one of the indicators of global climate changes. Spatio-temporal change and change patterns can be identified using various methods to facilitate human understanding global climate changes. Three empirical orthogonal function(EOF) techniques are discussed and applied to decades of sea-ice concentration(SIC) dataset in Arctic area for identifying independent patterns. It was found that: 1) discrepancies exist in magnitude and scope for each EOF pattern, however, the first two leading EOFs of variability possess high similarities in structure and shape; 2) Even though there are somewhat differences in amplitude of each PC mode, the first two leading PC modes maintain consistent in overall trend and periodicity; 3) There are significant discrepancies and inconsistencies in the third and fourth leading EOF and PC modes. The accuracies of three techniques are further validated in representing the physical phenomena of SIC anomaly patterns.展开更多
Background:Despite a growing population of patients starting hemodialysis in China,little is known about markers of mineral bone disease(MBD)and their management.We present data on prevalence and correlates of hypocal...Background:Despite a growing population of patients starting hemodialysis in China,little is known about markers of mineral bone disease(MBD)and their management.We present data on prevalence and correlates of hypocalcemia,hyperphosphatemia,and secondary hyperparathyroidism from the China Dialysis Outcomes and Practice Patterns Study(DOPPS),with evaluation of whether these laboratory markers triggered changes in management.Methods:We compared the frequency of measurement and prevalence of poor control of MBD markers in China DOPPS with other DOPPS regions.We also used generalized estimating equations to assess correlates of MBD markers,and separate models to assess predictors of vitamin D and phosphate binder prescriptions in the China DOPPS.Results:Severe hyperphosphatemia(>7 mg/dL)and secondary hyperparathyroidism(>600 pg/mL)were common(27%and 21%prevalence,respectively);both were measured infrequently(14.9%and 3.2%of patients received monthly measurements in China).Frequency of dialysis sessions was positively associated with hyperphosphatemia;presence of residual kidney function was negatively associated with both hyperphosphatemia and secondary hyperparathyroidism.Laboratory measures indicating poor control of MBD were not associated with subsequent prescription of active vitamin D or phosphate binder.Conclusions:There are substantial opportunities for improvement and standardization of MBD management in China.Development of country-specific guidelines may yield realistic targets and standardization of medication use accounting for availability and cost.展开更多
Objective To obtain information on the distribution of serotypes and antimicrobial agent susceptibilities to group B streptococcus (GBS) strains isolated in Beijing area from 1991 to 1996. Methods Bacterial is...Objective To obtain information on the distribution of serotypes and antimicrobial agent susceptibilities to group B streptococcus (GBS) strains isolated in Beijing area from 1991 to 1996. Methods Bacterial isolates of GBS were obtained from vaginal and cervical tract of pregnant and nonpregnant women in Beijing Tian Tan Hospital by culture. A total of 76 GBS strains were identified finally by coagglutination. Serotyping was determined by Standard Lancefield method. Susceptibility to test agents was assessed by determining the minimal inhibitory concentrations (MICs) with agar dilution method that was established by the National Committee for Clinical Laboratory Standards (NCCLS). Results Seven serotypes were identified among 76 GBS strains isolates. Types Ⅱ (33%), Ⅲ (23%) and Ⅰa (16%) were the predominant serotypes in pregnant and nonpregnant women. MICs of penicillin G and ampicillin were ≤0.06 μg/ml. MICs of cephazolin, cefuroxime and cefoperozone were 0.003 μg/ml 0.06 μg/ml. MICs of erythromycin were 0.003 μg/ml 0.03 μg/ml. MICs of gentamycin were 1 μg/ml 32 μg/ml. MICs of amikacin were 4 μg/ml ≥64 μg/ml, nearly 12.8% and 40.4% of the strains were resistant to gentamycin and amikacin, respectively. Conclusions Our study provides useful epidemiologic data for preparation of GBS type specific vaccines which can prevent GBS infections and antimicrobial agents susceptibility patterns in China. Routine reports on GBS susceptibilities by clinical laboratories and continuous surveillance for changes in the susceptibility are of considerable clinical importance.展开更多
The high rate digital acoustic communication technique for horizontal channels has been studied in this article. It is called as 'Pattern Time Delay Shift Coding (PDS) communication system.' The aim of the PDS...The high rate digital acoustic communication technique for horizontal channels has been studied in this article. It is called as 'Pattern Time Delay Shift Coding (PDS) communication system.' The aim of the PDS is to improve the quality of communication in shallow water. The open water experiments shoe that at the condition of 2 kHz bandwidth, the communication rate is more than 300 bit/s and error rate is at the level of 10-4. The details of PDS technique will be shown, including: principle of PDS coding, the model of Anti-multipath illterference and open water experimenis展开更多
Analytic formulas for acoustic interference patterns in shallow water are derived by ray method. Which can be used to guide acoustic measurements with limited horizontal distances. Some necessary approximations are ta...Analytic formulas for acoustic interference patterns in shallow water are derived by ray method. Which can be used to guide acoustic measurements with limited horizontal distances. Some necessary approximations are taken for a concise expression. The analytic for- mulas represent the quantitative relationships between the interference-pattern and the signal frequency, bandwidth, depth of source and horizontal distance. Monofrequent signals, com- plicated signals and frequency-modulated signals are all studied. Several inferences are also deduced from the formulas. Both numerical simulations and experiment data are presented to prove that these formulas and their inferences can describe the critical characters of the acoustic interference pattern in the waveguide with a satisfying precision.展开更多
基金This study is one of the research projects sponsored by the Monsoon Research Foundation of State Meteorological Administration.
文摘By using the one-point correlation method, calculations have been made of the northern early summer 500 hPa teleconnection patterns. Seven teleconnection patterns are revealed, namely, the Western Atlantic (WA), the Eastern Atlantic (EA), the Eurasian (EU), the Bengal / Northern Pacific (BNP), the Western Pacific (WP), the East Asian / Pacific (EAP), and the Huanghe / East Asian (HEA) patterns. Their centers are determined and their yearly intensity indices (1951-1990) are calculated. On this basis the relationship between their interannual variations and the drought / flood in China is examined. It is noted that the EU, HEA and EAP wave trains are closely related to the drought / flood in China. The HEA and EAP patterns strongly influence the precipitation in eastern China. For example, the fierce floods experienced in 1991 early summer over China are related to the weak EAP and strong HEA patterns.
文摘On the basis of the data of zooplankton biomass and three major taxa—— Copepoda, Chaetognatha andSiphonophora of May-June 1986, July-August and December 1987, the distributional patterns and the indicator species of zooplankton in the Kuroshio and adjacent waters of the East China Sea are preliminarily studied. The results are as follows:The horizontal distribution of zooplankton biomass and the abundance of copepods, chaetognaths and siphonophores arecurred in the continent area northwest of Taiwan and the south-centre section of the East China Sea continent, which are the mix front of different waters. Zooplankton in the water area inside of Ryukyu Islands presented low abundance and high diversity. There are clear seasonal variations in zooplankton biomass and abundance in the study area. The strength or weakness of different water masses and fronts is the basic reason for the variations of zooplankton biomass and abundance.The species composition of zooplankton in the study area is complex and varies, however, the tropic oceanic species predominates overwhelmingly. The distribution of different ecotype species evidences the distribution of different water masses and the state of mixture. The indicator species of each water mass are listed in the paper so as to provide grounds for the variation of currents in the Kuroshio area.The temperature and salinity of sea water are important factors affecting zooplankton distribution, composition and diversity , however the role of salinity is major. With the replacement of one season by another, the correlative levels of temperature and salinity to various zooplankton taxa are more or less significant.
基金financially supported by the National Natural Science Foundation of China (No.51704203)the PhD Early Development Program of Taiyuan University of Science and Technology (Nos. 20152008, 20152013, and 20152018)+2 种基金Shanxi Province Science Foundation for Youths (No. 201601D202027)Key Project of Research and Development Plan of Shanxi Province (Nos. 201603D111004 and 201603D121010)NSFC-Shanxi Coal Based Low Carbon Joint Fund (No. U1510131)
文摘A water model and a high-speed video camera were utilized in the 300-t RH equipment to study the effect of steel flow patterns in a vacuum chamber on fast decarburization and a superior flow-pattern map was obtained during the practical RH process. There are three flow patterns with different bubbling characteristics and steel surface states in the vacuum chamber: boiling pattern(BP), transition pattern(TP), and wave pattern(WP). The effect of the liquid-steel level and the residence time of the steel in the chamber on flow patterns and decarburization reaction were investigated, respectively. The liquid-steel level significantly affected the flow-pattern transition from BP to WP, and the residence time and reaction area were crucial to evaluate the whole decarburization process rather than the circulation flow rate and mixing time. A superior flow-pattern map during the practical RH process showed that the steel flow pattern changed from BP to TP quickly, and then remained as TP until the end of decarburization.
文摘OBJECTIVE: To study the sonographic features and patterns of cystic renal carcinomas. METHODS: Thirteen cases of cystic renal carcinoma confirmed by operation and pathology were examined by ultrasonography, and the cystic walls, septa and solid mural nodules were studied. RESULTS: Solid mural nodules of some cases and irregular thickening of the cystic walls and septa were characteristic findings for the ultrasonic diagnosis of cystic renal carcinomas. According to their pathologic mechanisms and sonographic features, cystic renal carcinomas were classified into 3 patterns: unilocular cystic mass, multiloculated cystic mass and cystic-solid mass. CONCLUSIONS: Typical cystic renal carcinomas can be well diagnosed, while atypical cases may be misdiagnosed as benign renal cysts by ultrasonography. Color Doppler ultrasonography and needle aspiration guided by ultrasonography are helpful in the diagnosis of these atypical cases.
基金Supported by the National Natural Science Foundation of China under Grant No 11274262the Natural Science Foundation of Hunan Province under Grand No 14JJ2046the Program for Changjiang Scholars and Innovative Research Team in Universities under Grant No IRT13093
文摘Molecular dynamics simulations are performed to study the nanoindentation models of monolayer suspended graphene and graphyne. Fullerenes are selected as indenters. Our results show that Young's modulus of monolayer-thick graphyne is almost half of that of graphene, which is estimated to be 0.50 TPa. The mechanical properties of graphene and graphyne are different in the presence of strain. A pre-tension has an important effect on the mechanical properties of a membrane. Both the pre-tension and Young's modulus plots demonstrate index behavior. The toughness of graphyne is stronger than that of graphene due to Young's modulus magnitude. Young's moduli of graphene and graphyne are almost independent of the size ratio of indenter to membrane.
文摘Two body centered tetragonal (bet) crystal structures of α'-Fe_(16)N_2 with x=0.25, z=0.3125 (Jack-1) and x=0.222, z=0.306 (Jack-2) respectively, were analyzed theoretically with EMS software package. The simulation of diffraction patterns indicates that both diffraction patterns of the same axis in these two structures obey bcc extinction rule. The conclusion is also obtained from the analyses of the diffracted waves. α'-Fe_(16)N_2 precipitates in the diffusion layer of ion-nitrided α-iron have been studied with transmission electron microscope (TEM). We have distinctly observed the electron diffraction patterns of α'-Fe_(16)N_2 in [100], [111], [110], [011], [210], [021], [311], [113], [331] and [133] zone axes with perfect symmetry, which indicate the parallel orientation relationship with α matrix:<001>α'//<001>α'// {100}.α'// {100}tα. The analyses of diffraction patterns, which obey bcc extinction rule, verify the bct structure of α'-Fe_(16)N_2 discovered by X-ray diffraction.
文摘We studied a new grain-cash cropping pattern composed of "barley/watermelon + waize-rice", comparing with "barley / watermelon-rice" (CKI), "watermelon-rice", (CK2). The experiment was conducted in CNRRI’s field for 3 yr, employing completely randomized design with three replications, and each plot occupied 207 m~2. The soil in the experiment field contained: N, 2.48 g. kg, quick effective P 4 mg. kg, and quick effective K 53 mg·kg. The varieties tested were Zhemai 2 (barley), Zhemi 1 (watermelon), Suyu 1 (maize), and Shanyou 63 (hybrid rice).
基金Project(41301420)supported by the National Natural Science Foundation of ChinaProject(12JJB005)supported by the Hunan Provincial Natural Science Foundation of China+1 种基金Project(2014VGE03)supported by the Key Lab of Virtual Geographic Environment from Ministry of Education,ChinaProject(LEND2013B04)supported by the NASA Key Laboratory of Land Environment and Disaster Monitoring,USA
文摘Change in Arctic sea ice extent is one of the indicators of global climate changes. Spatio-temporal change and change patterns can be identified using various methods to facilitate human understanding global climate changes. Three empirical orthogonal function(EOF) techniques are discussed and applied to decades of sea-ice concentration(SIC) dataset in Arctic area for identifying independent patterns. It was found that: 1) discrepancies exist in magnitude and scope for each EOF pattern, however, the first two leading EOFs of variability possess high similarities in structure and shape; 2) Even though there are somewhat differences in amplitude of each PC mode, the first two leading PC modes maintain consistent in overall trend and periodicity; 3) There are significant discrepancies and inconsistencies in the third and fourth leading EOF and PC modes. The accuracies of three techniques are further validated in representing the physical phenomena of SIC anomaly patterns.
基金This work was supported by grants from the Global support for the ongoing DOPPS Programs without restriction on publications by a variety of funders(For details see https://www.dopps.org/AboutUs/Support.aspx)Dr.Shuchi Anand is supported by U.S.National Institute of Diabetes,and Digestive and Kidney Diseases(No.NIDDK K-235K23DK101826-03)Dr.Jun Wang is supported by the National Natural Science Foundation of China(No.81470972).
文摘Background:Despite a growing population of patients starting hemodialysis in China,little is known about markers of mineral bone disease(MBD)and their management.We present data on prevalence and correlates of hypocalcemia,hyperphosphatemia,and secondary hyperparathyroidism from the China Dialysis Outcomes and Practice Patterns Study(DOPPS),with evaluation of whether these laboratory markers triggered changes in management.Methods:We compared the frequency of measurement and prevalence of poor control of MBD markers in China DOPPS with other DOPPS regions.We also used generalized estimating equations to assess correlates of MBD markers,and separate models to assess predictors of vitamin D and phosphate binder prescriptions in the China DOPPS.Results:Severe hyperphosphatemia(>7 mg/dL)and secondary hyperparathyroidism(>600 pg/mL)were common(27%and 21%prevalence,respectively);both were measured infrequently(14.9%and 3.2%of patients received monthly measurements in China).Frequency of dialysis sessions was positively associated with hyperphosphatemia;presence of residual kidney function was negatively associated with both hyperphosphatemia and secondary hyperparathyroidism.Laboratory measures indicating poor control of MBD were not associated with subsequent prescription of active vitamin D or phosphate binder.Conclusions:There are substantial opportunities for improvement and standardization of MBD management in China.Development of country-specific guidelines may yield realistic targets and standardization of medication use accounting for availability and cost.
文摘Objective To obtain information on the distribution of serotypes and antimicrobial agent susceptibilities to group B streptococcus (GBS) strains isolated in Beijing area from 1991 to 1996. Methods Bacterial isolates of GBS were obtained from vaginal and cervical tract of pregnant and nonpregnant women in Beijing Tian Tan Hospital by culture. A total of 76 GBS strains were identified finally by coagglutination. Serotyping was determined by Standard Lancefield method. Susceptibility to test agents was assessed by determining the minimal inhibitory concentrations (MICs) with agar dilution method that was established by the National Committee for Clinical Laboratory Standards (NCCLS). Results Seven serotypes were identified among 76 GBS strains isolates. Types Ⅱ (33%), Ⅲ (23%) and Ⅰa (16%) were the predominant serotypes in pregnant and nonpregnant women. MICs of penicillin G and ampicillin were ≤0.06 μg/ml. MICs of cephazolin, cefuroxime and cefoperozone were 0.003 μg/ml 0.06 μg/ml. MICs of erythromycin were 0.003 μg/ml 0.03 μg/ml. MICs of gentamycin were 1 μg/ml 32 μg/ml. MICs of amikacin were 4 μg/ml ≥64 μg/ml, nearly 12.8% and 40.4% of the strains were resistant to gentamycin and amikacin, respectively. Conclusions Our study provides useful epidemiologic data for preparation of GBS type specific vaccines which can prevent GBS infections and antimicrobial agents susceptibility patterns in China. Routine reports on GBS susceptibilities by clinical laboratories and continuous surveillance for changes in the susceptibility are of considerable clinical importance.
文摘The high rate digital acoustic communication technique for horizontal channels has been studied in this article. It is called as 'Pattern Time Delay Shift Coding (PDS) communication system.' The aim of the PDS is to improve the quality of communication in shallow water. The open water experiments shoe that at the condition of 2 kHz bandwidth, the communication rate is more than 300 bit/s and error rate is at the level of 10-4. The details of PDS technique will be shown, including: principle of PDS coding, the model of Anti-multipath illterference and open water experimenis
文摘Analytic formulas for acoustic interference patterns in shallow water are derived by ray method. Which can be used to guide acoustic measurements with limited horizontal distances. Some necessary approximations are taken for a concise expression. The analytic for- mulas represent the quantitative relationships between the interference-pattern and the signal frequency, bandwidth, depth of source and horizontal distance. Monofrequent signals, com- plicated signals and frequency-modulated signals are all studied. Several inferences are also deduced from the formulas. Both numerical simulations and experiment data are presented to prove that these formulas and their inferences can describe the critical characters of the acoustic interference pattern in the waveguide with a satisfying precision.