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1.
Compared to data on adolescents and adults, limited research has been conducted on biological corre- lates among young children with possible psychological difficulties, especially in Asian countries. By focusing on various peripheral biochemical indicators, we investigated potential biological correlates of psychological states in a community sample of Taiwanese school children aged 6-10 years. In total, 307 students (159 obese children and 148 normal-weight children) were selected from first- and fourth-grade school children in eight elementary schools in the Taipei metropolitan area in 2009. These children underwent a comprehensive health examination, including a physical examination, blood sample analysis, and questionnaire administration in a hospital. Differences in anthropometric and serum biochemical readings were compared between children with average and worse levels on each of the five psychological domains. We found that interleukin (IL)-1β [β = 1.29, 95 % confidence interval (CI) 0.50-2.09], IL-10 (β = 1.61, 95 % CI 〈0.01-3.24), fasting blood glucose (β = 0.08, 95 % CI 0.01-0.15), homocysteine (β = 0.63, 95 % CI 0.09-1.18), and aspar- tate transaminase (AST) (β = 0.15, 95 % CI 〈0.01-0.31) were significantly positively associated with anxiety. In addition, IL-113, insulin, AST, and alanine aminotransam- inase (ALT) were significantly positively associated with depression. Anger and disruptive behaviors were also related to specific biological correlates. Specific biological correlates, including AST/ALT, cardiovascular disease- related variables, and specific cytokines, were linked to particular psychological states among young children in this Asian population. These might provide a route for better understanding the biological aspects of children's mental health and might contribute to research on diag- nostic or predictive biomarkers for psychiatric diseases in young children.  相似文献   

2.
目的了解江西省吉安市人群高尿酸血症患病特点及相关危险因素分析。方法在2018年1月1日至7月30日期间于吉安医院体检的人群中,随机抽取1000名16岁及以上吉安常住居民体检者作为研究样本,统计不同年龄段、不同性别者高尿酸血症的患病率,并应用Logistic回归模型进行高尿酸血症相关危险因素分析。结果1000名体检者中高尿酸血症患病率为23.3%(95%CI20.68%~25.92%),其中男性患病率28.08%(95%CI24.44%~31.73%)明显高于女性患病率16.59%(95%CI13.01%~20.16%),具有统计学意义(P0.001)。多因素logistic回归分析显示收缩压(OR=1.014,95%CI=1.005-1.023,P=0.002)、甘油三酯(OR=1.263,95%CI=1.106-1.443,P=0.001)、低密度脂蛋白(OR=1.376, 95%CI=1.026-1.845,P=0.033)升高,肾小球滤过率(OR=0.985,95%CI=0.977-0.993,P0.001)和高密度脂蛋白(OR=0.612,95%CI=0.402-0.931,P=0.022)降低是高尿酸血症的独立危险因素。结论在江西省吉安地区人群中,收缩压、甘油三酯、低密度脂蛋白升高,肾小球滤过率和高密度脂蛋白降低是高尿酸血症的独立危险因素。积极控制血压、血脂,保护肾脏功能,对于预防和治疗高尿酸血症具有重要意义。  相似文献   

3.
A total of six d13C minimum events,i.e.,VI,V,IV,III,II,and I,were observed via a stable carbon and oxygen isotope analysis of infaunal benthic foraminifera Uvigerina spp.in gravity core OS03-1 in the southeastern Okhotsk Sea over the last 180 ka.These events occurred at112–109,102–90,85–76,57–54,44–40,and 17–10 ka BP.The largest negative excursions reached 2.5%in event V and were greater than 1%in the other events.We proposed that all d13C minimum events were caused by the increase in sea surface water productivity,the weakened formation of Okhotsk Sea intermediate water,and the enhancement of the oxygen minimum zone.The negative excursions were unaffected by methane hydrate destabilization and subsequent methane release based on the results obtained by using archaeal lipid markers.  相似文献   

4.
Understanding the stressor–response relationship between nutrient levels and algal biomass is a prerequisite for the management of eutrophication in lakes. In this study, a quantile regression(QR) approach was used to interpret the stressor–response relationships between nutrient(e.g., phosphorus, nitrogen) concentrations and algal biomass as measured by chlorophyll-a(Chl-a) levels. QR results indicated that Lake Dianshan and Lake Changdang,which are both heavily eutrophicated, were P-limited only.In contrast, Lake Kuilei, which has significantly lower nutrient levels and algal biomass than the other two lakes,was P- and N-limited. Moreover, in Lake Kuilei, N and P levels had significant interaction effects on the algal biomass at the upper quantiles(s [ 0.68). The degree to which the lakes were P-limited increased with rises in the mean total P concentration in the lakes. QR has many advantages over ordinary least squares regression for discriminating limiting factors and, in particular, allows us to estimate changes near the upper extremes of distributions associated with limiting factors. QR is adapted to more specialized risk management problems, such as early warnings of the risk of algal blooms.The probable value-at-risk of harmful algal blooms for Lake Kuilei, Lake Dianshan and Lake Changdang is s = 0.76(Chl-a = 9 mg/m3), s = 0.87(Chl-a = 24 mg/m3) and s = 0.72(Chl-a = 35 mg/m3), respectively. Given the results of the stressor–response relationship analysis, we conclude that reductions in P input represent the most feasible and least costly approach for managing eutrophication in the shallow lakes of the Lake Taihu Basin. To control the magnitude and duration of algal blooms in shallow lakes,reductions in P and N inputs are required. The 95 % CI bounds of slopes indicated that the interactions of nonnutrient factors with nutrients had strong impacts on the algal biomass in lightly eutrophicated Lake Kuilei. It is suggested that, in addition to reductions in nutrient loads,several ecological measures, such as an increase in the biomass of submerged macrophytes and the reduction of hydraulic retention time by flushing, could represent important components of an integrated approach to eutrophication management in the Lake Taihu Basin.  相似文献   

5.
Objective: To evaluate the association between p53 codon 72 polymorphism (R72P) and the risk ofcolorectal liver metastases. Methods: The p53 R72P genotype was identified by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method in 78 consecutive colorectal cancer patients with liver metastases and 214 age- and sex-matched cases with nonmetastatic colorectal cancer. Results: The R allele of the p53 R72P polymorphism was more frequently found in metastatic cases than in nonmetastatic cases (P=0.075). Carriers of the 72R allele had a 2.25-fold (95% CI (confidence interval)=1.05-4.83) increased risk of liver metastases. On the stratification analysis, 72R-carrying genotype conferred a 3.46-fold (95% CI=1.02-11.72) and a 1.05-fold (95% CI=0.36-3.08) increased risk of liver metastases for p53 overexpression-positive and negative colorectal cancers, respectively. Conclusion: These results demonstrate for the first time that the 72R allele of the p53 polymorphism has an increased risk for liver metastases in colorectal cancers positive for p53 overexpression.  相似文献   

6.
Objective: To investigate the relationships between endothelial nitric oxide synthases (eNOS) G894T and 27 bp-variable number tandem repeat (VNTR) gene polymorphisms and osteoporosis in the postmenopausal women of Chinese Han nationality. Methods: In the present study, 281 postmenopausal women from Xi’an urban area in West China were recruited, and divided into osteoporosis, osteopenia, and normal groups according to the diagnostic criteria of osteoporosis proposed by World Health Organization (WHO). The bone mineral density (BMD) values of lumbar vertebrae and left hips were determined by QDR-2000 dual energy X-ray absorptiometry. Blood samples were tested for plasma biochemical indicators including testosterone, estradiol, calcitonin, osteocalcin, and procollagen type I amino-terminal propeptide by enzyme-linked immunosorbent assay (ELISA), tartrate-resistant acid phosphatase by spectrophotometric method, and the content of nitric oxide by Griess method. Genome DNA was extracted from whole blood, and G894T polymorphism of eNOS gene was analyzed by using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method and 27 bp-VNTR polymorphism of eNOS gene was genotyped by PCR method. Then the relationships between genotypes and biochemical indicators, genotypes and osteoporosis, and haplotypes and osteoporosis were analyzed. Results: The average BMD values of the femoral neck, ward’s triangle and lumbar vertebrae 1~4 (L1~L4) in the subjects with T/T genotype in eNOS G894T locus were significantly higher than those in the subjects with G/T and G/G genotypes (P<0.05). The average BMD of the femoral neck in the subjects with a/a genotype of eNOS 27 bp-VNTR locus was evidently higher than that in the subjects with b/b genotype (P<0.05). The plasma testosterone and osteocalcin concentrations in the subjects of eNOS G894T G/T genotype were evidently higher than those in the subjects of other genotypes (P<0.05); the plasma estradiol concentration in the subjects of eNOS 27 bp-VNTR a/a genotype was obviously higher than that in the subjects of b/b genotype (P<0.01). eNOS G/G homozygous frequencies in osteoporosis women, osteopenia women, and normal women were 85.37%, 76.38%, and 83.87%, respectively (P>0.05). 0% osteoporosis woman, 0.79% osteopenia women, and 3.23% normal women were eNOS a/a homozygous (P<0.05). The frequencies of eNOS 27 bp-VNTR a allele were 5.33% in the osteoporosis group, 10.24% in the osteopenia group, and 16.13% in the normal group (P<0.05, odds ratio (OR)=0.29, 95% confidence interval (CI)=0.11~0.77), suggesting that a/a genotype and a allele might have protective effects on osteoporosis. The haplotype analysis showed that G-b was 87.7% (214/244) in the osteoporosis group (P<0.05, OR=2.48, 95% CI=1.18~5.18). G-a was 5.3% (13/244) in the osteoporosis group (P<0.05, OR=0.29, 95% CI=0.11~0.77). G-b was a risk factor for osteoporosis, and G-a a protective factor. Conclusion: eNOS G894T G/T genotype influenced the plasma testosterone and osteocalcin concentrations, and T/T genotype influenced BMD. eNOS 27 bp-VNTR a/a genotype increased plasma estradiol concentration to have a protective effect on osteoporosis.  相似文献   

7.
To assess associations between home indoor air environments and asthma,allergies and pneumonia,children aged 1–8 years were surveyed from 12 kindergartens in the city of Xi’an.2,020 questionnaires were responded with a response rate of 83.5%.The prevalences of doctor diagnosed asthma,hay fever,and pneumonia were 2.9%,3.6%,and 28.3%,respectively.Living close to a highway was a risk factor for current rhinitis(AOR 1.5,95%CI 1.2–1.8),eczema(AOR 1.7,95%CI 1.2–2.5),and diagnosed pneumonia(AOR 1.3,95%CI 1.0–1.6).Dampness problems in the home were associated with 50%–130%increases in the prevalences of asthma and allergy.Airing bed linen under sun-shine was protective,especially against rhinitis.Pet avoidance was consistently and significantly associated with asthma and allergy(AOR 1.3–2.4).Decoration of the home during children’s early life is a risk factor for current rhinitis(AOR 1.9,95%CI 1.3–2.9)and eczema(AOR 1.9,95%CI1.1–3.6).Risk factors for pneumonia were living in an apartment(AOR 1.4,95%CI 1.1–1.8),latex wall paint(AOR 1.3,95%CI 1.0–1.7),dampness(AOR 1.4–1.5),breast feeding\3 months(AOR 1.3,95%CI 1.0–1.7),never airing bed linen in sunshine(AOR 1.3,95%CI1.3–1.6),and cleaning children’s room less frequently than once per day(AOR 1.4,95%CI 1.1–1.7).This study demonstrates that home indoor environmental and life style factors may influence the health of children in Xi’an.  相似文献   

8.
Figuring out whether the sedimentary provenance regions of the thick deep-water turbidite systems deposited during Middle–Upper Ordovician in South Quruqtagh are the intracontinental uplifts or the peripheral orogenic belts is of great significance for us to understand the tectono-sedimentary nature of the northeastern Tarim Basin and basin-range coupling processes in the middle Paleozoic.This paper reports the in situ LA-ICP-MS U–Pb ages and Hf isotope data on detrital zircons from two Middle–Upper Ordovician sandstone samples which were collected from the Charchag Formation and the Zatupo Formation in South Quruqtagh,respectively.The results show that the studied two samples have extremely similar U–Pb age patterns and Hf isotopic compositions,reflecting multiphase tectonothermal events with age groups of 527–694,713–870 Ma(peaking at 760 Ma),904–1,090,1,787–2,094 Ma(peaking at 1,975 Ma)and 2,419–2,517 Ma.Combining previous studies,the presence of age groups of 713–1,090 and1,787–2,094 Ma,respectively,demonstrates that Tarim had ever been a part of Rodinia and Columbia supercontinent.Moreover,98%of 713–870 Ma detrital zircons are characterized by negative e Hf(t)values ranging from-38.07 to-0.61,which are highly consistent with those of Neoproterozoic granites from the Quruqtagh area.No Early Paleozoic ages(*470–500 Ma)signifying subduction or collision events in Altyn Tagh were detected in the two samples,indicating that the Middle–Late Ordovician sediments in South Quruqtagh and northern Mangar depression were mainly derived from intracontinental uplifts,i.e.,the North Quruqtagh uplift or the Tabei paleo-uplift,rather than the Altyn Tagh.In conjunction with regional sedimentary-tectonic background and previous studies,we proposed preliminarily that the northeastern Tarim remained as a passive continental margin in Late Ordovician and changed into an active-continental margin in Silurian due to the southward subduction of the South-Tianshan Ocean.  相似文献   

9.
The Arctic region, with magnificent ice cover on the surface of the Arctic Ocean and adjacent seas, is not only extremely sensitive to but also has strong amplification effects on climate change. Observations during the past decades have documented substantial retreat and thinning of the Arctic sea-ice cover, a process that is accelerating. Its feedback and impact on the global climate has become an important subject of current climate change research. Calcite tests of planktonic foraminifers are major constituents in pelagic sediments, and they provide valuable materials for the reconstruction of past oceanographic conditions. However, research is still sparse in the Arctic sea area because of limited availability of the materials for investigation. Here, we present a study of modern foraminifers from the plankton tow samples taken in the Makarov Basin of the Arctic Ocean during the fourth Arctic expedition of China. We have analyzed ecological information stored in the modern planktonic foraminifers and in their stable isotope signals, and established a relationship between the distribution of the main taxa and the environment. Our main observations are as follows:(1) in the Makarov Basin, the polar species Neogloboquadrina pachyderma(sinistral coiling) dominates the [150 lm planktonic foraminiferal assemblages.(2) The planktonic foraminifers live mainly in the upper halocline at a water depth of 50–100 m and less in the depth interval of 100–200 m.(3) Temperature change in the halocline can affect the absolute abundance of planktonic foraminifers and their distribution in the water column. The warmer halocline is more favorable to the development of planktonic foraminifers.(4) A lighter d18O value(2.11 %) of N. pachyderma(sin.) is recorded in the depth interval of 100–200 m, which is likely related to the isotopically light brines separated out during sea ice freezing. The relatively heavy d18O value(1.68 %–2.68 %, average 2.27 %) in the depth interval of 50–100 m may be influenced by the low salinity water with the relatively heavy d18O value formed during the sea-ice melting in the surface layer.  相似文献   

10.
This study quantifies the surface denudation rate of granitic regolith via the application of the in situ cosmogenic ^26Al and ^10Be depth profile in China. The concentration ranges of ^26Al and ^10Be in the quartz along the -3-m granitic regolith profile in Qinhuangdao are (4.9-23.1) × 10^5 and (2.3-36.6)×10^4 atoms/g, respectively. With the exception of the surface sample, both ^26Al and ^10Be concentrations decrease exponentially with sample depth. The Chi-square best-fitting results revealed a total denudation rate of -9 m/Ma averaged over a 103-105 a timescale, which is lower than the values observed in global granitic outcrops. Compared with global datasets, the flat terrain due to the lack of tectonic activities is most likely the dominant factor that controls the local denudation process. The surface sample offsets from the theoretical cosmogenic nuclide distribution implies that the denudation rate from river basin sediment could be overestimated because of the bioturbation in the surficial soil layer.  相似文献   

11.
本文主要通过回顾性研究新型冠状病毒感染(奥密克戎流行毒株)患者临床资料,探讨患者死亡的影响因素。以2022年12月至2023年1月在广西医科大学第二附属医院收治的经基因测序诊断为奥密克戎变异株新型冠状病毒感染患者906例为研究对象,根据纳入标准和排除标准,最终纳入患者858例,其中809例患者好转并出院,49例患者死亡。回顾性分析比较出院患者和死亡患者临床资料,并进行多因素逻辑回归分析患者死亡的影响因素。结果显示,两组患者在年龄(t=-0.640)、接种新冠疫苗(χ2=7.673)、高血压(χ2=9.557)、糖尿病(χ2=11.092)、脑梗(χ2=5.810)、发热(χ2=14.418)、呼吸困难(χ2=56.878)、味觉异常/丧失(χ2=5.876)、肺部啰音(χ2=27.655)及意识障碍(χ2=48.084)上存在显著差异(P<0.05)。多因素逻辑回归分析显示,年龄(OR...  相似文献   

12.
Polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) were monitored in a seasonal passive sampling scheme during June 2008 and January 2009 to investigate the spatial concentration, congener profiles and evaluate the potential inhalation risk in different functional areas in Tianjin, China. The spatial air concentrations and I-TEQs ranged 1.08×102–8.19×103 fg m?3 (average 2.63×103 fg m?3) and 4.08–325 fg I-TEQ m?3 (average 91.4 fg I-TEQ m?3) respectively for PCDD/Fs. The concentration and I-TEQs of PCBs were 3.08×104–3.01×105 fg m?3 (average 1.39×105 fg m?3) and 1.72–49.6 fg I-TEQ m?3 (average 18.5 fg I-TEQ m?3). It is obvious that PCB concentrations were several hundred times higher than the PCDD/Fs. However, the ambient air PCDD/Fs contributed a major part to the total toxicity equivalents, varying from 72.7% to 89.0% (average 81.8%). The atmospheric PCDD/F levels were observed to be higher in winter for most of sampling sites in the downtown. Besides, inhalation risk assessment showed that local residents might suffer more risk near the point sources than those in living area, industrial zones and background area in Tianjin City. However, the total daily dioxin intake was approximately several to hundreds of times lower than the WHO criteria, showing relatively low exposure risks from the impact of industry point sources in Tianjin City.  相似文献   

13.
The city of Chongqing has high outdoor temperatures and humidity throughout the year and consequently a high risk of dampness and mold problems in dwellings.As part of the China,Children,Homes,Health(CCHH),associations between home characteristics and children’s asthma,allergies,and related symptoms were investigated in Chongqing,China.A cross-sectional questionnaire survey on home characteristics including dampness and symptoms of asthma and allergies in 5299 children was performed.Data for 4754 children(3–6 years)and their homes were analyzed.Results showed that 35.1%of homes were reported to have"damp bedding",14.3%"condensation on window panes(higher than 5 cm)",11.6%"mouldy odor",9.3%"water leakage",8.3%"damp stains"and 5.3%"visible mould".Wheezing and rhinitis ever were reported for 27.0%and 51.1%children respectively,and rhinitis,wheezing,cough at night and eczema in the last 12 months were reported for 38.1%,20.5%,18.9%and 13.2%respectively.Doctor-diagnosed asthma was reported for 8.3%of children,and doctor-diagnosed rhinitis for 6.2%.Dampness in homes was generally strongly associated with asthma and allergies among Chongqing children.The strongest association was found between"visible mould"and doctor-diagnosed rhinitis,and the adjusted Odds Ratio(ORA)was 2.27(95%CI:1.48,3.49)."Damp bedding"was significantly associated with all asthma and allergic symptoms,but doctor-diagnosed asthma and rhinitis.The behavior of"putting bedding to sunshine"could effectively reduce the prevalence of asthma and allergic symptoms,and the risk of bedding affected with damp was reduced significantly when bedding was put to sunshine frequently.  相似文献   

14.
The steady-state absorption and fluorescence emission positions of diprotonated meso-tetrakis(4-sulfonatophenyl) porphyrin (H4TPPS2?) are dependent on the polarity of the selected two solid ionic liquids (ILs) and are red-shifted with the increase of cation size. The solvation dynamics process of H4TPPS2? in these ILs occurs on two well-separated time scales. The short components with 121.2–128.6 ps arise from the local motion of the ion-pairs in close proximity to the porphine core, and the long components with 1056.6–1261.8 ps are due to the collective translation motions of the ion-pairs. The dynamic Stokes shifts and the relaxation times increase with the increasing cation size of the ILs.  相似文献   

15.
A series of polymer solar cells (PSCs) based on poly (diketopyrrolopyrrole-terthiophene) (PDPP3T) and [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) as active layer were fabricated to investigate the effect of 1,8- diiodooctane (DIO) on the performance of PSCs. The power conversion efficiency (PCE) of PSCs was increased from 3.77 % to 4.37 % for the cells with DIO additive. The underlying reason may be attributed to that DIO additive could make PC71BM more dispersive in the active layer, forming a better bicontinuous interpenetrating network for excition dissociation and charge carrier transport. There- fore, the short circuit current density (Jsc) and fill factor (FF) was increased from 8.25 to 9.18 mA/cm2 and from 67.2 % to 70.0 % for the PSCs with DIO additive compared with PSCs without DIO additive.  相似文献   

16.
Environmental tobacco smoke (ETS) is a well- known reason of many adverse health consequences in pregnant women. Exposure of ETS during pregnancy may increase the risk of some fetal diseases in pregnant women and/or birth defects in neonates. Many countries have implemented laws to control smoking and free of second hand smoke in all enclosed workplaces. In China, anti- smoking law was enforced in March 2010. We aimed to assess the exposure of pregnant women to cotinine after anti-smoking law was implemented in China. The urine samples were collected from 2,100 volunteers from Zhejiang Province, China and urinary concentration of cotinine was measured using gas chromatography and mass spectrometry. Cotinine was detected in 87 % of the pregnant women. The GM and 95th percentile concentration in pregnant women were 4.28 and 44.00 μg/L, respectively. Similarly, the GM and 95th concentration of cotinine were significantly higher in smoking group than in non-smoking group (P 〈 0.0001). Our results indicate that pregnant women in China are at the high risk of exposure ETS. Further attempts are required to make strategies to find out the sources of ETS exposure and prevent smoking at public places especially during pregnancy.  相似文献   

17.
The reverse leakage characteristics of AlGaNbased ultraviolet light-emitting diodes fabricated on sapphire substrate are studied by temperature-variable current–voltage(I–V)measurement from 300 to 450 K.At low-reverse bias range(0–0.5 V),the reverse leakage current exhibits tunneling characteristics.Meanwhile,under a more negative reverse bias range([0.5 V),the log(I)–log(V)plots exhibit close-to-linear dependency,which is in good agreement with the transport mechanism of space-charge limited current.A phenomenological leakage current model focusing on electron transmission primarily through continuous defect band formed by linear defects like dislocations is suggested to explain the reverse current–voltage characteristics.  相似文献   

18.
El Nio-Southern Oscillation(ENSO)has affected penguins and their habitats in the western Antarctic Peninsula.We used both historical penguin population dynamics data(1980–2012)and sedimentary lipids in penguin droppings(1916–2001)on Ardley Island to examine the responses of the Antarctic ecosystem to ENSO(El Nin o/La Nin a)events.The results showed that during the last 30 years,climate,marine food chain changes,and human activity have significantly affected penguin population sizes on Ardley Island.The Chinstrap(Pygoscelis antarctica)and Ade′lie(P.adeliae)penguin populations showed a good correlation with ENSO events.The Chinstrap penguin population decreased significantly because it was more sensitive to increasing human disturbance(e.g.,scientific activity and tourism)than Ade′lie and Gentoo(P.papua),particularly during the breeding season.Compositional features of n-alkanes in penguin dropping sediments revealed that organic matter came from lower terrestrial plants,bacteria and algae.C23was the main nalkane heavy hydrocarbon indicating mosses and lichens in the penguin’s diet.Variation in the ratio of nC23/nC17was closely correlated with ENSO events.The bacteria intrusion index(ratio of(iC15:0?aC15:0)/nC15:0for fatty acids)reflected significant increases in microorganism activity during several periods in this area.Meanwhile,the CPIA value for fatty acids decreased because micro-organisms contributed light hydrocarbon fatty acids to penguin droppings.Our results showed that the fine structure and molecular indices of fatty acids and n-alkanes in penguin dropping sediments can be used to explain climate-driven microbial processes,and to reveal the important role that microbes and bacteria play in the relatively simple Antarctic ecosystem.  相似文献   

19.
A scanning Fabry–Perot interferometer (SFPI) was first developed and deployed at the Langfang near Space Environment Field Scientific Observation Station (39.38°N, 116.65°E) of the National Space Science Center, CAS. The instrument is designed to measure the mesospheric and thermospheric wind velocities using the atomic oxygen 557.7-nm and 630.0-nm emissions. Data from February 28 to March 3 and February 28 to March 15 in 2011 were chosen for case study and mean value study, respectively. The errors of the meridional and zonal winds are 6.5 and 7.5 m/s at 557.7-nm and at 630.0-nm, they are 7.1 and 6.6 m/s, respectively. During the whole experiment, the instrument has performed in good condition and provided high-quality data. The mean neutral wind data were consistent with that predicted by HWM07. Good agreement has been found in between the SFPI and a neighbor Meridian Project Fabry–Perot interferometer (MP FPI), with a corresponding coefficient (r 2) larger than 80 %. In general, the scanning FPI meets the design goal, and it is a useful ground-based instrument for measuring mesospheric and thermospheric winds at middle latitudes and is able to provide high-quality data for future scientific studies.  相似文献   

20.
The Yunmengshan metamorphic core complex in the middle part of the Yanshan Fold and Thrust Belt records crust extension processes of the eastern North China Craton during its peak destruction.Development of the metamorphic core complex was controlled by the generally NNE-striking Dashuiyu Shear Zone.The shear zone dips SE and becomes shallower NE-wards,leading to exposures of a ductile shear zone in the southern and middle parts and brittle faults in the northern part.Exposure structures,microstructures,and quartz C-axis fabrics indicate that the ductile shear zone belongs to an extensional shear zone with a top-to-the-SE shear sense.Deformation temperatures of 300–520°C suggest a midcrustal origin for the ductile shear zone.A ductile deformation belt in the footwall of the shear zone is only as wide as 1–3 km,indicating no widespread mid-crustal ductile flow in the region during the deformation.Zircon U–Pb dating of dykes and plutons as well as hornblende and biotite40Ar/39Ar dating demonstrate that the metamorphic core complex originated at 135 Ma and experienced intense shearing of the Dashuiyu Shear Zone,development of the supradetachment basins,and synkinematic intrusion during 135–125 Ma.The metamorphic core complex was subjected to rapid exhumation during 125–114 Ma when the Dashuiyu Shear Zone suffered continuous activity and passive doming.The shear zone and its hanging wall were cut or replaced by a series of brittle faults when they wereuplifted to a brittle regime,showing that exhumation took place in continuous extensional activities.The metamorphic core complex turned into slow exhumation in an extensional regime in the following latest Early Cretaceous.The evolution history suggests that the Yunmengshan metamorphic core complex was developed by the rolling-hinge model,a common formation mechanism for intraplate metamorphic core complexes in the North China Craton,under the continuous NW–SE extension during the Early Cretaceous(135–100 Ma).  相似文献   

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