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Use of Foot Measurements as Sonographic Parameter for Estimation of Fetal Age
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作者 Bushra Abdel Malik Mohammed Ibrahim +3 位作者 Qurashi Ali Mohamed Yousef Qurain Turki Alshammari Saddig Jastaniah 《Open Journal of Medical Imaging》 2017年第4期248-262,共15页
Objectives: this research was conducted to describe the ultrasonic measurements of the foot full measurements (FFM) and their importance in the antenatal care (ANC). Material and methods: the Descriptive quantitative ... Objectives: this research was conducted to describe the ultrasonic measurements of the foot full measurements (FFM) and their importance in the antenatal care (ANC). Material and methods: the Descriptive quantitative cross-sectional study conducted in the ultrasound department at Alshaekh Mohammed Ali Fadol hospital in Omdurman locality. The study included 400 healthy Sudanese pregnant women whom in the 1st (late), 2nd and 3rd trimesters (i.e., after 10 weeks gestational age) of different parity and ages (15 years old and above);they have regular menstrual cycle and well certain of their last menstrual period and calculated date of delivery. Ultrasonographic measurement of Full Foot Length1 (FFL1), Foot Full Length2 (FFL2), and Foot Full Width (FFW) of all pregnant women were done. Sonographically we measured fetal foot from 14 to 40 weeks of gestation. Results: the study revealed that the mean FFL1 was 58.7 ± 12.9 mm. The minimum measurement was 18.8 mm, and the maximum was 89.1 mm, while the mean value of FFL2 was 53.4 ± 11.4 mm, with minimum value 17.5 mm and maximum 81.7 mm, and the mean FFW was 23.7 ± 5.1 mm, with minimum value 7.0 mm and maximum 38.0 mm. Conclusion: a strongly significant relationships were observed between (FFL1, FFL2, FFW) and gestational age (p = 0.00). However there is no significant difference between the FFL1, FFL2, and correlations with sex of embryo, residence, occupation, parity, maternal height, socioeconomic status, bleeding during this pregnancy, chronic illness, and caesarian section, moreover there are significant correlations between the FFL1, FFL2 and the (maternal age, maternal weight, and body mass index), but in the measurement of the fetal FFW there were no significant correlations with (sex of embryo, maternal age, body mass index, residence, occupation, parity, socioeconomic status, bleeding during this pregnancy, chronic illness, and caesarian section). Also there are significant correlations between the FFW and the maternal weight and height. 展开更多
关键词 GESTATIONAL age Full FOOT measurementS FOOT Full Length1 (FFL1) FOOT Full Length2 (FFL2) and FOOT Full WIDTH (FFW)
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K-Ar age, geochemical, and Sr-Pb Isotopic compositions of keban magmatics, elazig, EasternAnatolia, Turkey 被引量:1
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作者 Sevcan Kurum 《Natural Science》 2011年第9期750-767,共18页
Keban magmatics consist of plutonic rocks of acidic and intermediate compositions with diffe rent phases. They are the equivalent of surface rocks. In the current study on plutonic rocks, general petrographic features... Keban magmatics consist of plutonic rocks of acidic and intermediate compositions with diffe rent phases. They are the equivalent of surface rocks. In the current study on plutonic rocks, general petrographic features, disequilibrium textures such as skeletal formation in minerals, poikilitic texture, oscillatory zoning, and mineral fragmentation, and growth states are observed. Besides these microscopic properties, the existence of rounded mafic enclaves of various sizes, petrographic synplutonic dykes, and field data support the idea that mafic and felsic magmas are mixed. Keban magmatics have I-type, metaluminous-peraluminous characteristics. Diorites and quartz diorites have low-K tholeiitic features, whereas tonalites have low-K calcalkaline features. Compared with diorites, tonalites are richer in terms of LREE (Rock/ Chondrite);Rb, Sr, and Ba (LILE);and Hf, Zr, Th, and U (HFSE) elements. LILE enrichment, which signals the crustal contamination of mantle- originated magmas, is particularly observable in tonalites. In both rock groups, the negative anomaly of Nb is a sign of similarity of pluton to the subduction zone magma series. Based on the K-Ar geochronology dating of amphibole minerals, the ages of these rocks are found to be 75.65 ± 1.5 and 59.77 ± 1.2 Ma in tonalites and 84.76 ± 1.8 and 84.35 ± 1.7 Ma in diorite and quartz diorites. The 87Sr/86Sr isotope ratios in tonalites are 0.705405 and 0.706053, whereas these ratios are 0.704828 and 0.704754 in dioritic rocks. Pb isotope ratios are similar in both rock types. 展开更多
关键词 Keban Magmatics k-ar age Pb-Sr ISOTOPES Geochemistry
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A Comparison Study of Synkinematic Illite Isolation,Quantitative X-ray Powder Diffraction,and K-Ar Dating for Direct Fault Gouge Analyses
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作者 ZHENG Yong LI Haibing +2 位作者 LI Junjie ZHANG Guohe SI Jialiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第2期636-650,共15页
K-Ar dating of synkinematic illite is increasingly recognized as a central method to constrain the timing of shallow crustal faulting.Methods of efficient sample preparation and quantitative identification of illite p... K-Ar dating of synkinematic illite is increasingly recognized as a central method to constrain the timing of shallow crustal faulting.Methods of efficient sample preparation and quantitative identification of illite polytypes are critical to acquiring K-Ar isotope data for authigenic clays.In this respect,we compared the commonly used clay size separation method through centrifugation with vacuum filtration technology,showing that the former is prone to extract fractions with finer particle sizes under similar conditions,thus improving the error in the authigenic end-member age.Additionally,we demonstrated that the side-packed mounting method for X-ray diffraction analysis can significantly enhance the randomness in powder samples,thus improving the quantification accuracy compared with the front-packed and back-packed methods.The validity of our quantification method was confirmed by comparing Profex■modeling patterns with a suite of synthetic mixtures of known compositions,yielding an average analytical error of 3%.Dating results of these artificial mixtures and the reference materials indicated that a large range in percentages of detrital illite and a sufficient amount of age data will produce reliable results for ages of both extrapolated end-members.However,if the range is limited,the extrapolated age close to those of datasets is still reliable. 展开更多
关键词 illite polytypes fault gouge clay size separation mounting method Profex■ extrapolated k-ar age
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K-Ar Geochronology of Mesozoic Mafic Dikes in Shandong Province, Eastern China: Implications for Crustal Extension 被引量:17
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作者 LIUShen HURuizhon ZHAOJunhong FENGCaixia 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第6期1207-1213,共7页
Based on K-Ar isotope analyses, Mesozoic mafic (and alkali ultramafic) dikes from western and eastern Shandong Province, China, are dated at 88.2±1.70 Ma to 169.5±3.7 Ma with the majority of ages ranging fro... Based on K-Ar isotope analyses, Mesozoic mafic (and alkali ultramafic) dikes from western and eastern Shandong Province, China, are dated at 88.2±1.70 Ma to 169.5±3.7 Ma with the majority of ages ranging from 90 Ma to 140 Ma. The emplacement of the dikes suggests a major Yanshanian (Cretaceous) crustal extension in Shandong province. Together with other available age data, this study suggests four periods of crustal extension at about 80 Ma, 100 Ma, 120 Ma and 140 Ma, respectively. Besides the effect of collapse of the Yanshanian orogenic belt on the emplacement of the mafic dikes in Shandong in the Cretaceous, the mantle plume and the extensive left-lateral advection and extension of the Tanlu fault also have controlled the crustal extension and the emplacement of the mafic dikes in eastern Shandong and western Shandong, respectively. 展开更多
关键词 crustal extension mafic dike k-ar age mantle plume Tanlu fault SHANDONG eastern China
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Assess Medical Screening and Isolation Measures Based on Numerical Method for COVID-19 Epidemic Model in Japan 被引量:3
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作者 Zhongxiang Chen Huijuan Zha +2 位作者 Zhiquan Shu Juyi Ye Jiaji Pan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第2期841-854,共14页
This study aims to improve control schemes for COVID-19 by a numerical model with estimation of parameters.We established a multi-level and multi-objective nonlinear SEIDR model to simulate the virus transmission.The ... This study aims to improve control schemes for COVID-19 by a numerical model with estimation of parameters.We established a multi-level and multi-objective nonlinear SEIDR model to simulate the virus transmission.The early spread in Japan was adopted as a case study.The first 96 days since the infection were divided into five stages with parameters estimated.Then,we analyzed the trend of the parameter value,age structure ratio,and the defined PCR test index(standardization of the scale of PCR tests).It was discovered that the self-healing rate and confirmed rate were linear with the age structure ratio and the PCR test index using the stepwise regression method.The transmission rates were related to the age structure ratio,PCR test index,and isolation efficiency.Both isolation measures and PCR test medical screening can effectively reduce the number of infected cases based on the simulation results.However,the strategy of increasing PCR test medical screening would encountered a bottleneck effect on the virus control when the index reached 0.3.The effectiveness of the policy would decrease and the basic reproduction number reached the extreme value at 0.6.This study gave a feasible combination for isolation and PCR test by simulation.The isolation intensity could be adjusted to compensate the insufficiency of PCR test to control the pandemic. 展开更多
关键词 SEIDR epidemic model multi-level and multi-objective problem PCR test index age structure isolation measure
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K-Ar age of the Cenozoic volcanic rocks in the Nangqen Basin, Qinghai Province and its geological significance 被引量:7
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作者 DENG Wanming SUN Hongjuan ZHANG Yuquan 《Chinese Science Bulletin》 SCIE EI CAS 2000年第11期1015-1019,共5页
The Nangqen Basin is one of the typical shearing-extensional basins situated in the north part of the Hengduan Mts. Nine ages of the Cenozoic volcanic rocks from the basin by K-Ar isotope-dilution technique have been ... The Nangqen Basin is one of the typical shearing-extensional basins situated in the north part of the Hengduan Mts. Nine ages of the Cenozoic volcanic rocks from the basin by K-Ar isotope-dilution technique have been reported in the note. The apparent ages of whole rock and separated biotite range from 32.04 to 36.50 Ma. The 40Ar-K (%) correlation isochronal line shows that there existed neither argon excessing , nor radiogenetic argon loosing, i.e. the age represents the true diagenetic time. Volcanic activity in this area occurred in the post-collision environment and is controlled by lithosphere substantial thickening and violent intercontinental shearing-strike slip faults. There is age difference of the magmatic activity in the east, the west and the north Tibet. The multi-periodic eruption-intrusion of the magmatic melt since Cenozoic is a tracer showing the pulsating uplift of the Tibetan Plateau. 展开更多
关键词 Nangqen Basin VOLCANIC ROCKS k-ar age TIBETAN PLATEAU PLATEAU uplift.
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K-Ar age of young volcanic rocks and excess argon——Binary mixing model and quantitative study of excess argon effect 被引量:4
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作者 Darning Li Wenji Chen Qi Li 《Chinese Science Bulletin》 SCIE EI CAS 2000年第7期659-664,共6页
A binary mixing model for excess argon is suggested in the note. According to thismodel and the data of excess argon component obtained in our experiment, a quantitative study of the effect of excess argon on real K-A... A binary mixing model for excess argon is suggested in the note. According to thismodel and the data of excess argon component obtained in our experiment, a quantitative study of the effect of excess argon on real K-Ar age of young volcanic rocks is done. The result indicates that the effect of 5% excess argon component in samples on K-Ar age of the samples more than 2 Ma is less than 7.36% and can lead K-Ar age of 0.5 Ma samples to increase by 32.4%, while 1% excess argon component leads K-Ar age of 0.5 Ma samples to increase by 6.26%. Therefore, when pre-processed excess argon component is ≤1%, K-Ar age of the samples more than 0.5 Ma should be credible. On this basis we suggest a principal opinion for evaluation of previous K-Ar dating results and propose that the matrix is used to determine K-Ar age of young volcanic rocks. For the samples less than 0.2 Ma, in the case of high excess argon content, even if only 1% excess argon component exists in their matrix, it can also greatly affect their K-A 展开更多
关键词 YOUNG VOLCANIC rock k-ar age EXCESS ARGON BINARY mixing model.
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Acceptability of an acupuncture intervention for geriatric chronic pain: an open pilot study 被引量:5
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作者 Marie-France Couilliot Veronique Dareest +6 位作者 Bruno.Tenenbaum Gerard Delahaye Philippe Ercolano Maud Carcaille Pavia Vytopilova Bruno Tenenbaum Eric Vicaut 《Journal of Integrative Medicine》 SCIE CAS CSCD 2013年第1期26-31,共6页
OBJECTIVE: This study investigated the acceptability and effectiveness of acupuncture for persistent musculoskeletat pain in the elderly and assessed the conditions for a future controlled trial. METHODS: A total of... OBJECTIVE: This study investigated the acceptability and effectiveness of acupuncture for persistent musculoskeletat pain in the elderly and assessed the conditions for a future controlled trial. METHODS: A total of 60 patients, hospitalized in a geriatric hospital were enrolled. The intervention consisted of eight acupuncture sessions. The main outcome was the patient's participation rate. Regarding pain, the evaluation was based on pre- and post-treatment variations. As a high proportion of the patients had cognitive impairment, the behavioral pain scale DOLOPLUS-2 was chosen although self evaluation was used wherever possible. RESULTS: The mean age of the patients was 83 years. The acceptance rate was very high (89.6%) and 90% of the patients completed the entire course of treatment. After five weeks, the mean DOLOPLUS score had decreased significantly (P〈0.01). The patients reported improved sleep quality and a reduction in their anxiety symptoms. Furthermore, caregivers noticed a decrease in patient aggressiveness making care easier. CONCLUSION: Our results suggest that acupuncture is highly acceptable and could be very useful in the management of chronic pain when performed in very old frail people with chronic physical and mental disability. TRIAL REGISTRATION IDENTIFIER: NCT01043692 ClinicalTrials.gov. 展开更多
关键词 ACUPUNCTURE PAIN aged pain measurement pilot projects
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Petrology,Geochemistry and Nd-Sr-Pb Isotopic Properties of Volcanic Rocks in Daheishan Island,Penglai,Shandong Province 被引量:3
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作者 傅永涛 李安春 《Marine Science Bulletin》 CAS 2003年第2期29-39,共11页
The major elements, trace elements. K-Ar age and Sr-Nd-Pb isotopie systems ofthe Cenozoic volcanic rocks in Daheishan Island and Cishan, Penglai, Shandong Province aremeasured. The volcanic rocks ( olivine-nephelinite... The major elements, trace elements. K-Ar age and Sr-Nd-Pb isotopie systems ofthe Cenozoic volcanic rocks in Daheishan Island and Cishan, Penglai, Shandong Province aremeasured. The volcanic rocks ( olivine-nephelinite and nephcline-basanite ) in Daheishan Islanderupted periodically in an interval of 0.32 Ma, from 8.72 Ma. 8.39 Ma. 8.08 Ma to 7.73 Ma. Thevolcanic rocks arc all rich in light REEs. They are similar to the OIB-type alkali basalt in thetrace elements normalized model by primordial mantle: rich in high field elements such as Nb and Ta,and imcompatible elements such as Cs. Rb, Ba, Th. U. The volcanic rocks show a depletion of K andRb elements. It is suggested by the trace elements that the olivine-nephelinite in Daheishan Islandis originated from deep resources under the continental mantle. ε Nd (0) values of the volcanicrocks in Daheishan Island and Cishan are 5.31~8.51 and 7.33 respectively, suggesting that thevolcanic rocks are from the depleted mantle resources, which have higher Sm/Nd ratios than the CHUR.^(143)Nd /^(144)Nd ratios ot Daheishan Island olivine-nephelinite and Cishan alkali basalts are0.512 910~0.513 074 and 0.513 014 respectively. The ^(87)Sr /^(86)Sr of Daheishan Island volcanicrocks are lower than that of Cishan, 0.703 427 ~0.703 482 and 0.703 895 respectively. The DaheishanIsland olivine-nephelinite has the Pb isotopie values as follows: ^(206)Pb/^(204)Pb= 18.028 9~17.972 8. ^(207)Pb / ^(204)Pb = 15.435 8 ~15.402 2 and ^(208)Pb /^(204)Pb = 38.087 6~37.997 5.lower than those of Cishan basanite. The Cishan basanite has ^(206)Pb/^(204)Pb= 18.240 1. ^(207)Pb/^(204)Pb= 15.564 5 and ^(208)Pb /^(204)Pb = 38.535. The authors suggest that theolivine-nephelinite in Daheishan Island is similar to the E-type MORB or Hawaii OIB, and the alkalibasalts in Cishan similar to the Kerguelen OIB. The dominant mantle components of DM+PREMA andperhaps DM ( Dupal type ) are the dominant mantle components for volcanic rocks in Daheishan Islandand Cishan. The PREMA component plays an important role. 展开更多
关键词 daheishan island penglai cenozoic volcanic rocks k-ar age DM PREMA
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Significance of K-Ar age of bimodal volcanic rocks at Wangtian'e volcano,Changbaishan area 被引量:1
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作者 Qicheng Fan Ruoxin Liu +1 位作者 Daming Li Qi Li 《Chinese Science Bulletin》 SCIE EI CAS 1999年第7期660-664,共5页
Wangtian’ e volcano, about 30 km south of Tianchi volcano is another large scale volcano center on the south slope of Changbaishan with its nearly 4 000 km^2 area of volcanic rocks distributed over the border area of... Wangtian’ e volcano, about 30 km south of Tianchi volcano is another large scale volcano center on the south slope of Changbaishan with its nearly 4 000 km^2 area of volcanic rocks distributed over the border area of the Chinese side. Based on the field occurrence, petrology and K-Ar age dating of its volcanic rocks, it can be shown that the Wangtian’e volcano had experienced two developing stages of shield forming and cone forming, while its volcanic activities can be divided into three periods: Changbai period (? —2.87 Ma), Wangtian’e period (2.69—2.41 Ma) and Hongtoushan period (2.12 Ma). Its petrographic change goes from trachybasalt→basaltic trachyandesite, trachyte→alkalic rhyolite, with a feature of bimodal volcanic rock combination similar to yet a bit different from that of Tianchi volcano, and is a new scene for study of volcanic magma evaluation of Changbaishan volcanoes. 展开更多
关键词 Wangtian’e VOLCANO BIMODAL VOLCANIC rock k-ar age.
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K-Ar isotope evidence for age of the first and only independent tellurium deposit 被引量:1
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作者 银剑钊 陈毓川 +2 位作者 周剑雄 杨百川 骆耀南 《Chinese Science Bulletin》 SCIE EI CAS 1995年第22期1933-1934,共2页
The Dashuigou tellurium deposit found in 1991 in Shimian County, Sichuan Province of China, is the first and only independent tellurium deposit in the world. The deposit is located on the western margin of the Yangtze... The Dashuigou tellurium deposit found in 1991 in Shimian County, Sichuan Province of China, is the first and only independent tellurium deposit in the world. The deposit is located on the western margin of the Yangtze Platform. The tellurium ore bodies taking vein and lentiform shapes filled the N-S fractures in the pyrrhotite veins in hornblende schists at the northern limb of the Middle and Lower Triassic metamorphic arch. The main wallrock alterations are biotitization, sericitization, greisenization, dolomitization, 展开更多
关键词 k-ar isotope evidence for age of the first and only independent tellurium deposit
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K-Ar Ages and Geochemistry of the Mariana Trough Basalts
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作者 穆治国 张成 +4 位作者 陈成业 刘驰 黄宝岭 苗国均 吴士迎 《Chinese Science Bulletin》 SCIE EI CAS 1994年第22期1900-1904,共5页
Studies on the Mariana Trough basalts began in the early 1970s, and during the past two decades, they are getting deeper and deeper with the Deep Sea Drilling Project devoted to the back-arc and the trough.From the ea... Studies on the Mariana Trough basalts began in the early 1970s, and during the past two decades, they are getting deeper and deeper with the Deep Sea Drilling Project devoted to the back-arc and the trough.From the early 1980s to 展开更多
关键词 MARIANA TROUGH oceanic THOLEIITE k-ar age geochemistry.
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Relationship between life satisfaction and sympathovagal balance in healthy elderly males at home at night
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作者 Kohzoh Yoshino Tomoko Morimoto +3 位作者 Takahiro Itagaki Shigetaka Iketani Masami Nagata Morihiro Tsujishita 《Health》 2012年第11期1068-1072,共5页
The aim of this study is to clarify how well-being correlates with autonomic nervous system (sympathovagal) balance in healthy elderly males at home at night awake and resting. The RR-interval and body acceleration of... The aim of this study is to clarify how well-being correlates with autonomic nervous system (sympathovagal) balance in healthy elderly males at home at night awake and resting. The RR-interval and body acceleration of 39 healthy elderly male subjects were recorded with an ambulatory device for 72 hours. The normalized high-frequency (0.15 - 0.4 Hz) power (HFnu) of RR-interval variability (sympathovagal balance index) was calculated from 10 min long data sets that satisfied all of the following conditions: 1) average body acceleration was less than 30 mG, 2) the subject was at home, 3) the subject was awake, and 4) more than 95 percent of the time-series of instantaneous heart rate was within 40 to 160 [bpm]. Subjects recorded their subjective well-being level, including life satisfaction level, on a Visual Analogue Scale (VAS) questionnaire. We investigated the correlation between the subjective well-being level and mean HFnu. A significant negative correlation between life satisfaction level and mean HFnu (r = –0.47, p = 0.004) was observed. This result implies that sympathovagal balance becomes the predominant state of the sympathetic nervous system in healthy elderly males with relatively high life satisfaction while at home at night awake and resting. 展开更多
关键词 Quality of LIFE Psychophysiological measures AUTONOMIC Nervous System HEART RateVariability HAPPINESS aged HOME
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Evolution History of Gassan Volcano, Northeast Japan Arc
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作者 Ryo Oizumi Masao Ban Naoyoshi Iwata 《Open Journal of Geology》 2018年第7期647-661,共15页
Evolution history of the volcano is essential not only to characterize the volcano, but also consider magma genesis beneath the volcano. Most of the stratovolcanoes in northeast Japan follow a general evolutional cour... Evolution history of the volcano is essential not only to characterize the volcano, but also consider magma genesis beneath the volcano. Most of the stratovolcanoes in northeast Japan follow a general evolutional course: cone building, horse-shoe shaped caldera forming collapse, and post-caldera stages. However, the detailed history of each stage is not well investigated. We investigated evolution history of young edifice of Gassan volcano, representative stratovolcano in rear side of northeast Japan arc. Most of the products are lavas, which are divided into two groups by geomorphologic and geologic features. The former (Gassan lower lavas) is composed of relatively thin and fluidal lavas, whose original geomorphology remains a little, while the latter (Gassan upper lavas) is composed of relatively thick and viscous lavas, whose original geomorphology is moderately preserved. Based on geologic features, the upper lavas can be further divided into Gassan upper north lavas and upper summit lavas in ascending order. After the formation of the thick lavas, horse-shoe shaped caldera was formed by the instability of the edifice, probably triggered by fault activity. No evidence of post caldera activity inner part of it is observed. Based on K-Ar data, estimated age of Gassan lower lavas is ca. 0.75 to ca. 0.6 Ma, those of Gassan upper north and upper summit lavas are ca. 0.60 to ca. 0.55 Ma and ca. 0.55 to ca. 0.45 Ma. The eruption rate is estimated to be ca. 0.0004 km3/1000 years in Gassan lower lavas and ca. 0.02 km3/1000 years in Gassan upper summit lavas. These values are lower than the eruption rate of representative Japanese stratovolcanoes. 展开更多
关键词 STRATOVOLCANO Andesitic LAVA Evolution History Gassan VOLCANO NE Japan k-ar age DATING
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Should the K-Ar isotopic ages of olivine basalt be reconsidered?
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《Chinese Science Bulletin》 SCIE CAS 1998年第19期1670-1671,共2页
关键词 Should the k-ar isotopic ages of olivine basalt be reconsidered
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On emplacement ages of lam-proites in Zhenyuan County,Guizhou Province,China 被引量:6
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作者 Weixuan Fang Ruizhong Hu +3 位作者 Wenchao Su Jiafei Xiao Liang Qi Guohao Jiang 《Chinese Science Bulletin》 SCIE EI CAS 2002年第10期874-880,共7页
Emplacement ages of lamproites that comprise lamproite and olivine lamproite in Zhenyuan County, Guizhou Province, China, have been constrained by the whole-rock Sm-Nd and Rb-Sr isochron methods and the whole rock K-A... Emplacement ages of lamproites that comprise lamproite and olivine lamproite in Zhenyuan County, Guizhou Province, China, have been constrained by the whole-rock Sm-Nd and Rb-Sr isochron methods and the whole rock K-Ar method. Intrusive activities of lamproites in the Sinantang area of Zhenyuan County, Guizhou Province, took place during the Late Cambrian, as indicated by the Sm-Nd isochron ages (t) = (503±17) (2σ) Ma and by the Rb-Sr isochron ages (t) = (501.2±4.6) (2σ) Ma. Intrusive activities of olivine lamproites at the Maping with Ⅱ -type diamond and Xitou in Zhenyuan County, Guizhou Province, took place from the Late Cambrian to the Early Ordovician, as evidenced by the Sm-Nd isochron ages (t) = (502±27) (2σ) Ma and by the Rb-Sr isochron age (t) = (502± 27) (2σ) Ma. This suggests that the upwelling hot materials derived from the deep mantle were emplaced from the Late Cambrian to the Early Ordovician (503-497 Ma), while the time terminal of cooling of the geothermal event of 展开更多
关键词 the SM-ND ISOCHRON age the RB-SR ISOCHRON age whole rock k-ar method LAMPROITE Zhenyuan COUNTY of Guizhou Prov-ince China.
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Fission-Track Age of Bobai County and Baise Basin Tektite in Guangxi 被引量:2
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作者 张峰 黄志涛 莫进尤 《Chinese Science Bulletin》 SCIE EI CAS 1994年第21期1806-1809,共4页
Tektite arouses great concern of the scientists in different fields, mainly because it is a synthesized material produced by impact between terrestrial material and extraterrestrial material, and the falling or formin... Tektite arouses great concern of the scientists in different fields, mainly because it is a synthesized material produced by impact between terrestrial material and extraterrestrial material, and the falling or forming process of tektite has never 展开更多
关键词 TEKTITE FISSION-TRACK age measurement.
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Intraoperative body temperature and emergence delirium in elderly patients after non-cardiac surgery:A secondary analysis of a prospective observational study
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作者 Guojun Wang Shuting He +3 位作者 Mengyao Yu Yan Zhang Dongliang Mu Dongxin Wang 《Chinese Medical Journal》 SCIE CAS CSCD 2023年第19期2330-2339,共10页
Background:Emergence delirium(ED)is a kind of delirium that occured in the immediate post-anesthesia period.Lower body temperature on post-anesthesia care unit(PACU)admission was an independent risk factor of ED.The p... Background:Emergence delirium(ED)is a kind of delirium that occured in the immediate post-anesthesia period.Lower body temperature on post-anesthesia care unit(PACU)admission was an independent risk factor of ED.The present study was designed to investigate the association between intraoperative body temperature and ED in elderly patients undergoing non-cardiac surgery.Methods:This study was a secondary analysis of a prospective observational study.Taking baseline body temperature as a reference,intraoperative absolute and relative temperature changes were calculated.The relative change was defined as the amplitude between intraoperative lowest/highest temperature and baseline reference.ED was assessed with the confusion assessment method for intensive care unit at 10 and 30 min after PACU admission and before PACU discharge.Results:A total of 874 patients were analyzed with a mean age of 71.8±5.3 years.The incidence of ED was 38.4%(336/874).When taking 36.0°C,35.5°C,and 35.0°C as thresholds,the incidences of absolute hypothermia were 76.7%(670/874),38.4%(336/874),and 17.5%(153/874),respectively.In multivariable logistic regression analysis,absolute hypothermia(lowest value<35.5°C)and its cumulative duration were respectively associated with an increased risk of ED after adjusting for confounders including age,education,preoperative mild cognitive impairment,American Society of Anesthesiologists grade,duration of surgery,site of surgery,and pain intensity.Relative hypothermia(decrement>1.0°C from baseline)and its cumulative duration were also associated with an increased risk of ED,respectively.When taking the relative increment>0.5°C as a threshold,the incidence of relative hyperthermia was 21.7%(190/874)and it was associated with a decreased risk of ED after adjusting above confounders.Conclusions:In the present study,we found that intraoperative hypothermia,defined as either absolute or relative hypothermia,was associated with an increased risk of ED in elderly patients after non-cardiac surgery.Relative hyperthermia,but not absolute hyperthermia,was associated with a decreased risk of ED.Registration:Chinese Clinical Trial Registry(No.ChiCTR-OOC-17012734). 展开更多
关键词 HYPOTHERMIA HYPERTHERMIA Emergence delirium Pain measurement Cognitive dysfunction Non-cardiac surgery aged Post-anesthesia care unit
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Anatexis in Himalayan crust:Evidence from geochemical and chronological investigations of Higher Himalayan Crystallines 被引量:9
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作者 YANG Xiaosong1, JIN Zhenmin2 & MA Jin1 1. State Key Laboratory of Earthquake Dynamics, Institute of Geology, China Earthquake Administration, Beijing 100029, China 2. Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074, China 《Science China Earth Sciences》 SCIE EI CAS 2005年第9期1347-1356,共10页
Migmatization in Higher Himalayan Crystallines (HHC) results from anatexis. The widely distributed migmatites in HHC are an important clue to investigate the relationship be- tween anatexis and the origins of Higher H... Migmatization in Higher Himalayan Crystallines (HHC) results from anatexis. The widely distributed migmatites in HHC are an important clue to investigate the relationship be- tween anatexis and the origins of Higher Himalayan leucogranites (HHL), and to understand the effect of anatexis on crustal evolution during the post-collision period. We studied in detail the chemical features of three basic constituent parts of the migmatites, i.e. leucosome, mesosome and melanosome, and determined the K-Ar ages of leucosomes. Our studies indicate that type-I leucosome is the product of crystallization of melt generated by partial melting of mesosome at source region, but type-II leucosome and HHL probably underwent crystallization differentiation of plagioclase during melt aggregation and migration. The age of 22.67 Ma of Type-I leucosome, which is a little older than the beginning of MCT movement, indicates that anatexis may have played an important role in the formation of MCT. That the ages of type-II leucosome (ranging from 14.82 to 18.37 Ma) are consistent with that of HHL provides new chronological evidence for the relationship between migmatization and HHL. We obtained a very young age of 6.23 Ma of Type-II leucosome that provides new time constraint on magma activity in the central segment of Higher Himalayas. 展开更多
关键词 HIGHER HIMALAYAN Crystallines migmatite anatexis leucosome k-ar age.
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Which fetal growth charts should be used?A retrospective observational study in China 被引量:2
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作者 Jianxin Zhao Ying Yuan +13 位作者 Jing Tao Chunyi Chen Xiaoxia Wu Yimei Liao Linlin Wu Qing Zeng Yin Chen Ke Wang Xiaohong Li Zheng Liu Jiayuan Zhou Yangwen Zhou Shengli Li Jun Zhu 《Chinese Medical Journal》 SCIE CAS CSCD 2022年第16期1969-1977,共9页
Background:The fetal growth charts in widest use in China were published by Hadlock>35 years ago and were established on data from several hundred of American pregnant women.After that,>100 fetal growth charts w... Background:The fetal growth charts in widest use in China were published by Hadlock>35 years ago and were established on data from several hundred of American pregnant women.After that,>100 fetal growth charts were published around the world.We attempted to assess the impact of applying the long-standing Hadlock charts and other charts in a Chinese population and to compare their ability to predict newborn small for gestational age(SGA).Methods:For this retrospective observational study,we reviewed all pregnant women(n=106,455)who booked prenatal care with ultrasound measurements for fetal biometry at the Shenzhen Maternity and Child Healthcare Hospital between 2012 and 2019.A fractional polynomial regression model was applied to generate Shenzhen fetal growth chart ranges for head circumference(HC),biparietal diameter(BPD),abdominal circumference(AC),and femur length(FL).The differences between Shenzhen charts and published charts were quantified by calculating the Z-score.The impact of applying these published charts was quantifed by calculating the proportions of fetuses with biometric measurements below the 3rd centile of these charts.The sensitivity and area under the receiver operating characteristic curves of published charts to predict neonatal SGA(birthweight<10th centile)were assessed..Results:Following selection,169,980 scans of fetal biometry contributed by 41,032 pregnancies with reliable gestational age were analyzed.When using Hadlock references(<3rd centile),the proportions of small heads and short femurs were as high as 8.9%and 6.6%in late gestation,respectively.The INTERGROWTH-21st standards matched those of our observed curves better than other charts,in particular for fat-free biometry(HC and FL).When using AC<10th centile,all of these references were poor at predicting neonatal SGA.Conclusions:Applying long-standing Hadlock references could misclassify a large proportion of fetuses as SGA.INTERGROWTH-21st standard appears to be a safe option in China.For fat-based biometry,AC,a reference based on the Chinese population is needed.In addition,when applying published charts,particular care should be taken due to the discrepancy of measurement methods. 展开更多
关键词 INFANT NEWBORN Pregnancy Growth chart Gestational age Birth weight Prenatal care BIOMETRY Fetal growth reference Ultrasound measurement Hadlock charts INTERGROWTH-21st charts China
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