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Frontal Sinus Fractures: Management at the Yalgado Ouedraogo University Hospital Centre (Burkina Faso)
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作者 Arsène Coulibaly Patrik Gane-Bang +2 位作者 Joseph Wend-Toin Biogo Ibraïma Traoré Tarcissus Konsem 《Open Journal of Stomatology》 2024年第1期42-54,共13页
Introduction: Frontal sinus fractures are potentially serious. They are defined as a solution of continuity, open or closed, of one or both bone tables of the frontal sinus. This study aims to report on the management... Introduction: Frontal sinus fractures are potentially serious. They are defined as a solution of continuity, open or closed, of one or both bone tables of the frontal sinus. This study aims to report on the management of them at the Yalgado OUEDRAOGO University Hospital Centre. Methodology: It is a descriptive cross-sectional study with retrospective collection from January 01, 2016 to December 31, 2018. Patients with frontal sinus fractures were managed at the Yalgado OUEDRAOGO University Hospital Centre through CT-scan proof. Results: Over three years, a total of 102 cases of frontal sinus fractures were collected with 29.9 years as average age. There were 96 men. Workers in the informal sector and pupils/students represented 58.90% of patients. The residence of the patients was urban in 68.80% of cases and rural in 31.40%. Road traffic accidents (RTAs) happened in 90.20%, and involved 2-wheelers in 98.20%. None of these drivers was wearing a helmet. The type III frontal fracture of Ioannides et al. represented 51.9% of cases. In 89.21% of cases, other facial and/or cranioencephalic injuries were compounded to frontal sinus fractures. No surgical management was observed in 82 (80.39%) patients and surgical management in 20 (19.61%) patients. The outcome was favourable, but sequelae and/or complications were noted in 10 patients who had surgery and 30 patients who did not. Conclusion: These results enforce helmet wearing for all riders of two-wheeled machines. In addition, vaccinations to prevent meningitis in frontal sinus fractures with dural breach should be systematic. 展开更多
关键词 MANAGEMENT frontal Sinus Fracture Burkina Faso
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Analysis on the Characteristic of Frontal Precipitation Weather Situation in Jilin Area 被引量:1
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作者 马虹旭 杨仲江 +1 位作者 王伟 孙杰 《Meteorological and Environmental Research》 CAS 2010年第7期56-60,共5页
By analyzing and studying a lot of weather charts and the weather condition of several typical cases,some kinds of unconventional high-altitude and ground weather situations whether the ground cold,warm front had the ... By analyzing and studying a lot of weather charts and the weather condition of several typical cases,some kinds of unconventional high-altitude and ground weather situations whether the ground cold,warm front had the precipitation in Jilin area were summarized.The results showed that the temperature field was the main element field which affected the weather variation.The analysis and research on the movement condition of cold,warm air in the different temperature-pressure field configuration in the high-altitude was the key of frontal precipitation weather forecast. 展开更多
关键词 frontal precipitation Temperature-pressure field Movement of cold and warm air Jilin China
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Frontal assessment battery: A tool for screening minimal hepatic encephalopathy?
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作者 Karina Zamprogno de Souza Maria Penha Zago-Gomes 《World Journal of Hepatology》 CAS 2016年第30期1262-1268,共7页
AIMTo apply the Frontal Assessment Battery to cirrhotic patients with or without overt hepatic encephalopathy (OHE) and controls. METHODSThe frontal assessment battery (FAB) was applied to 87 patients with liver cirrh... AIMTo apply the Frontal Assessment Battery to cirrhotic patients with or without overt hepatic encephalopathy (OHE) and controls. METHODSThe frontal assessment battery (FAB) was applied to 87 patients with liver cirrhosis (16 with and 71 without OHE) and 40 control subjects without cirrhosis treated at the alcohol and liver outpatient clinics and the gastroenterology ward of the Cassiano Antônio de Moraes University Hospital (Hospital Universit&aacute;rio Cassiano Antônio de Moraes - HUCAM), Esp&iacute;rito Santo, Brazil. RESULTSThe average FAB score was lower for the cirrhotic than for the non-cirrhotic patients (10.6 &plusmn; 3.67 vs 12.25 &plusmn; 2.72, P = 0.015). The FAB score was lower for the cirrhotic patients with OHE than for the patients without OHE (8.25 &plusmn; 4.55 vs 11.14 &plusmn; 3.25, P = 0.027). The total FAB score was lower for the cirrhotic patients without OHE than for the non-cirrhotic patients, although this difference was not significant (11.14 &plusmn; 3.25 vs 12.25 &plusmn; 2.72, P = 0.067). Nevertheless, the difference in the scores on the subtest that assessed the ability to inhibit a response previously conditioned to a stimulus was significant (1.72 &plusmn; 0.93 vs 2.2 &plusmn; 0.85, P = 0.011). CONCLUSIONThe present study indicates that the FAB is a promising tool for outpatient minimal HE screening and the assessment of HE severity. 展开更多
关键词 Executive functions frontal lobe Hepatic encephalopathy Minimal hepatic encephalopathy Liver cirrhosis frontal assessment battery
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Functional role of frontal electroencephalogram alpha asymmetry in the resting state in patients with depression:A review
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作者 Yu-Hong Xie Ye-Min Zhang +2 位作者 Fan-Fan Fan Xi-Yan Song Lei Liu 《World Journal of Clinical Cases》 SCIE 2023年第9期1903-1917,共15页
Depression is a psychological disorder that affects the general public worldwide.It is particularly important to make an objective and accurate diagnosis of depression,and the measurement methods of brain activity hav... Depression is a psychological disorder that affects the general public worldwide.It is particularly important to make an objective and accurate diagnosis of depression,and the measurement methods of brain activity have gradually received increasing attention.Resting electroencephalogram(EEG)alpha asymmetry in patients with depression shows changes in activation of the alpha frequency band of the left and right frontal cortices.In this paper,we review the findings of the relationship between frontal EEG alpha asymmetry in the resting state and depression.Based on worldwide studies,we found the following:(1)Compared with individuals without depression,those with depression showed greater right frontal EEG alpha asymmetry in the resting state.However,the pattern of frontal EEG alpha asymmetry in the resting state in depressive individuals seemed to disappear with age;(2)Compared with individuals without maternal depression,those with maternal depression showed greater right frontal EEG alpha asymmetry in the resting state,which indicated that genetic or experience-based influences have an impact on frontal EEG alpha asymmetry at rest;and(3)Frontal EEG alpha asymmetry in the resting state was stable,and little or no change occurred after antidepressant treatment.Finally,we concluded that the contrasting results may be due to differences in methodology,clinical characteristics,and participant characteristics. 展开更多
关键词 DEPRESSION frontal electroencephalogram alpha asymmetry frontal asymmetry Resting state Neurological indicator
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Proposed Simple, Efficient Free Hand Technique for Frontal External Ventricular Drain (EVD) in Case of Small Ventricle: A Report of New Technique
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作者 Fawaz Eljili Marhoom Abdelradi Emad Ibrahim Ahmed 《Open Journal of Modern Neurosurgery》 2023年第3期121-128,共8页
Background: EVD is a common procedure done in neurosurgery and the residents should master it and this is what exactly means that it should be simple, safe, fast and accurate. EVD can be done through many entry points... Background: EVD is a common procedure done in neurosurgery and the residents should master it and this is what exactly means that it should be simple, safe, fast and accurate. EVD can be done through many entry points to the different part of the lateral ventricle but the famous site is the anterior horn of the lateral ventricle which is commonly approached through Kocher’s point which is a famous point for all neurosurgeon by its measurements of allocation. The commonest problem with EVD insertion into the anterior horn is the navigation of the ventricular cavity with the right trajectory and so the location of the catheter tip in the right place near the foramen of monro to ensure CSF draining. Size of the ventricle plays significant role in the success of the procedure especially free hand technique. The more dilated ventricle, the more chance to hit the ventricular cavity especially from the first trial and vice versa. In case of small ventricle, the procedure with free hand technique seems more complicated and the chance to hit the ventricle from the first trial may reduce especially with non-expert surgeon but may succeed in the following trials with increased risk of complications with more trials. Purpose: Most EVD’s are placed with freehand technique which depends on the operator skills to navigate the ventricle with right trajectory and hit the ventricle from the first trial, because many trials may complicate the procedure and produce undesirable side effects. So the key in this free hand technique is how to ensure the success from the first trial. In case of small anterior horn of the lateral ventricle, the procedure is even more difficult with the free hand technique and the classic Kocher point needs an expert to get the right trajectory to navigate such small ventricle. Our point idea came from this prospective and aimed at raising the success of the procedure especially in the first attempt with simple technique. Method: It is a new entry point for EVD insertion through frontal burr hole gained by the intersection of two lines: the first is running vertically from the ipsilateral medial canthus downward and the second is running horizontal along the coronal suture which is usually palpable as ridge on the scalp extended lateral from the bregma. Burr hole is done just anterior to this intersection and catheter is placed in a perpendicular trajectory toward the ventricular cavity. Result: It has been used in about (n = 50 cases) fulfilling the criteria of radiological small ventricle as defined and they were candidates for EVD insertion by free hand technique. Only 3 cases (6%) out of the 50 cases failed in the first attempt but succeeded in the following trial. So high rate of success in first trial is seen in the most of cases using this technique during a period of one year of our practice without significant side effects seen. Conclusion: Our study is not conclusive and needs further studies for more evaluation. It was a suggested point other than the classic Kocher point in case of free hand EVD insertion in small ventricle. We recommend to try it and report any advantages or disadvantages to the literature. 展开更多
关键词 frontal Ventriculostomy Freehand EVD Small Ventricle EVD frontal Horn EVD
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Role of Kuroshio frontal eddy in exchange between shelf water and Kuroshio water in East China Sea 被引量:10
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作者 Guo Binghuo and Ge Renfeng First Institute of Oceanography, State Oceanic Administration, Qingdao 266003, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1997年第1期1-18,共18页
Basic patterns of the reversal of the Kuroshio water toward the shelf, intrusion of the shelf mixed water into the Kuroshio and uplifting of the near-bottom nutrient-rich water into the upper layer by the pumping of t... Basic patterns of the reversal of the Kuroshio water toward the shelf, intrusion of the shelf mixed water into the Kuroshio and uplifting of the near-bottom nutrient-rich water into the upper layer by the pumping of the frontal eddy are analyzed on the basis of satellite infrared images and hydrologic, chemical and biological observations. Results show that the Kuroshio frontal eddies play a very important role in the exchange between the shelf water and the Kuroshio water. The estimation of the average volume transports for three frontal eddy events indicates that the shelf mixed water entrained by an eddy into Kuroshio is 0.44×10~6 m3/s and the reversal Kuroshio water onto the shelf region only 0.04×10~6 m3/s. Along the whole shelf edge, the volume transport of the shelf mixed water entrained by the eddies into the Kuroshio is 1.8×10~6 m3/s. The nutrient (NO3-N) flux pumped to the euphotic zone and input to the continental shelf through a column with 1 m wide is 974 μmol/(s·m) when there is frontal eddy and only 79 μmol/(s·m) in the case of no frontal eddy. Yearly nutrient (NO3-N) flux input to the shelf area caused by the frontal eddy is 1.7×10~5 t/a. 展开更多
关键词 Kuroshio in the East China Sea frontal eddy water exchange nutrient flux
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Electroacupuncture at the Wangu (GB 12) acupoint suppresses expression of inflammatory factors in the hippocampus and frontal lobe of rats with post-stroke depression 被引量:6
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作者 Rubo Sui Lei Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第36期2839-2844,共6页
Electroacupuncture was performed at the Wangu (GB 12) acupoint, whose position is similar to the cerebellar fastigial nucleus in rats with post-stroke depression. Results showed that the expression of nuclear factor... Electroacupuncture was performed at the Wangu (GB 12) acupoint, whose position is similar to the cerebellar fastigial nucleus in rats with post-stroke depression. Results showed that the expression of nuclear factor-κB and the levels of tumor necrosis factor-α and interleukin-1β decreased. Simultaneously, the extent of edema in the hippocampus and frontal lobe decreased, and the morphology of the nerve cells recovered to near normal. In addition, fluoxetine treatment displayed a similar effect on post-stroke depression as electroacupuncture at GB 12 acupoint. The results indicate that electroacupuncture at GB 12 acupoint can reduce the levels of cytokines in the hippocampus and frontal lobe of rats with post-stroke depression, and thus provide a neuroprotective effect on post-stroke depression. 展开更多
关键词 post-stroke depression HIPPOCAMPUS frontal lobe cytokines ELECTROACUPUNCTURE Wangu (GB 12) acupoint traditional Chinese medicine neural regeneration
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Analysis of the CHRNA7 gene mutation and polymorphism in Southern Han Chinese patients with nocturnal frontal epilepsy 被引量:3
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作者 Zhi-Hong Chen Chun Wang +6 位作者 Lin-Gan Wang Mu-Qing Zhuo Zhi-Hong Tang Qiong-Xiang Zhai Qian Chen Yu-Xiong Guo Yu-Xin Zhang 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2015年第4期330-333,共4页
Objective:To detect the CHRNA7 gene mutation and polymorphism in Southern Han Chinese patients with nocturnal frontal lobe epilepsy(NFLE).Methods:Blood samples were collected from 215 Southern Han Chinese patients wit... Objective:To detect the CHRNA7 gene mutation and polymorphism in Southern Han Chinese patients with nocturnal frontal lobe epilepsy(NFLE).Methods:Blood samples were collected from 215 Southern Han Chinese patients with NFLE and 200 healthy Southern Han Chinese control subjects.Genomic DNA was extracted,and CHRNA7 whole genome exons were amplified by the polymerase chain reaction and subjected to Sanger sequencing.Results:No CHRNA7 gene mutation was detected in all of the NFLE patients.However,five single nucleotide polymorphisms(SNPs)in sporadic cases were found,located in exons 5,6.and 7 of the CHRNA7 gene.Among them,c.690G>A and c.698A>G are known SNPs,while c.370G>A,c.654C>T,and c.497-498delTG were newly discovered SNPs.These SNPs were also found in some of the healthy controls.Conclusions:No CHRNA7 gene mutation was identified in Southern Han Chinese patients with NFLE.The CHRNA7 gene is probably not responsible for NFLE in this population. 展开更多
关键词 Autosomal DOMINANT NOCTURNAL frontal EPILEPSY CHRNA7 Gene Mutation POLYMORPHISM
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Obese Adolescents with Type 2 Diabetes Mellitus Have Hippocampal and Frontal Lobe Volume Reductions 被引量:9
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作者 Hannah Bruehl Victoria Sweat +2 位作者 Aziz Tirsi Bina Shah Antonio Convit 《Neuroscience & Medicine》 2011年第1期34-42,共9页
The rates of type 2 diabetes (T2DM) continue to parallel the rising rates of obesity in the United States, increasingly affecting adolescents as well as adults. Hippocampal and frontal lobe reductions have been found ... The rates of type 2 diabetes (T2DM) continue to parallel the rising rates of obesity in the United States, increasingly affecting adolescents as well as adults. Hippocampal and frontal lobe reductions have been found in older adults with type 2 diabetes, and we sought to ascertain if these brain alterations were also present in obese adolescents with T2DM. In a cross-sectional study we compared MRI-based regional brain volumes of 18 obese adolescents with T2DM and 18 obese controls without evidence of marked insulin resistance. Groups were matched on age, sex, school grade, ethnicity, socioeconomic status, body mass index, and waist circumference. Relative to obese controls, adolescents with T2DM had significantly reduced hippocampal and prefrontal volumes, and higher rates of global cerebral atrophy. Hemoglo-bin A1c, an index of long-term glycemic control, was inversely associated with prefrontal volume and positively associ-ated with global cerebral atrophy (both p < 0.05). Brain integrity is negatively impacted by T2DM already during ado-lescence, long before the onset of overt macrovascular disease. Paralleling the findings of greater vascular and renal complications among obese adolescents with severe insulin resistance and T2DM relative to their age-matched peers with type 1 diabetes, we find clear evidence of possible brain complications. Our findings call for aggressive and early intervention to limit the negative impact of obesity-associated insulin resistance leading to T2DM on the developing brains of adolescents. 展开更多
关键词 OBESITY Type 2 DIABETES HIPPOCAMPUS frontal LOBE Adolescents
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Temporal Variations of the Frontal and Monsoon Storm Rainfall during the First Rainy Season in South China 被引量:11
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作者 YUAN Fang WEI Ke +2 位作者 CHEN Wen FONG Soi Kun LEONG Ka Cheng 《Atmospheric and Oceanic Science Letters》 2010年第5期243-247,共5页
The temporal variations in storm rainfall during the first rainy season (FRS) in South China (SC) are investigated in this study. The results show that the inter-annual variations in storm rainfall during the FRS in S... The temporal variations in storm rainfall during the first rainy season (FRS) in South China (SC) are investigated in this study. The results show that the inter-annual variations in storm rainfall during the FRS in SC seem to be mainly influenced by the frequency of storm rainfall, while both frequency and intensity affect the inter-decadal variations in the total storm rainfall. Using the definitions for the beginning and ending dates of the FRS, and the onset dates of the summer monsoon in SC, the FRS is further divided into two sub-periods, i.e., the frontal and monsoon rainfall periods. The inter-annual and inter-decadal variations in storm rainfall during these two periods are investigated here. The results reveal a significant out-of-phase correlation between the frontal and monsoon storm rainfall, especially on the inter-decadal timescale, the physical mechanism for which requires further investigation. 展开更多
关键词 the first rainy season in South China the frontal storm rainfall the monsoon storm rainfall temporal variations
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SYNTHESIS OF MACROPOROUS POLYACRYLAMIDE AND POLY(NISOPROPYLACRYLAMIDE) MONOLITHS VIA FRONTAL POLYMERIZATION AND INVESTIGATION OF PORE STRUCTURE VARIATION OF MONOLITHS 被引量:2
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作者 燕青芝 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2009年第5期747-753,共7页
A novelty method,frontal polymerization(FP),was employed to directly produce a series of polyacrylamide (PAM),poly(N-isopropylacrylamide)(PNIPAM) and acrylamide-N-isopropylacrylamide copolymer macroporous monoliths. F... A novelty method,frontal polymerization(FP),was employed to directly produce a series of polyacrylamide (PAM),poly(N-isopropylacrylamide)(PNIPAM) and acrylamide-N-isopropylacrylamide copolymer macroporous monoliths. Field emission scanning electronic microscope and mercury intrusion method were adopted to measure some parameters of these monoliths,such as frame,pore size distribution as well as porosity.Effects of types of monomer,thicker and surfactant on porous structure of monoliths were studied.A variet... 展开更多
关键词 frontal polymerization Macroporous monolith Pore structure variation Morphology.
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Study on the Interaction between Strychnine and Bovine Serum Albumin by Capillary Electrophoretic Frontal Analysis 被引量:2
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作者 Shao Ping FU Xiao Zhe ZHANG +3 位作者 Feng ZHANG Qing XU Hong Bin XIAO Xin Miao LIANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第9期1233-1236,共4页
The protein binding constant, binding sites of the Strychnos alkaloid-strychnine and bovine serum albumin (BSA) was determined by capillary electrophoretic frontal analysis (CE-FA) for the first time. The experime... The protein binding constant, binding sites of the Strychnos alkaloid-strychnine and bovine serum albumin (BSA) was determined by capillary electrophoretic frontal analysis (CE-FA) for the first time. The experiment was carried out in a polyacrylamide-coated fused silica capillary (48.4 cm×50 μm i.d., 38.1 cm effective length) with 20 mmol/L citrate/MES buffer (pH 6.0, ionic strength 0.17). The applied voltage was 12 kV and detection wavelength was set at 257 nm. The plateau height of the peak was employed to determine the unbound concentration of drug in BSA equilibrated sample solution based on the external drug standard in the absence of protein. The present method provides a convenient, accurate technique for the early stage of drug screening. 展开更多
关键词 STRYCHNINE binding constant capillary electrophoretic frontal analysis bovine serumalbumin
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The numerical simulation of the Kuroshio frontal eddies in the East China Sea using a hybrid coordinate ocean mode 被引量:2
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作者 JIA Yongjun ZHANG Youguang LIN Mingsen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第5期31-41,共11页
A hybrid coordinate ocean model (ltYCOM) is used to simulate the Kuroshio frontal eddies in the East China Sea (ECS). The research area is located (20°-32°N, 120°-132°E). Using tile simulatin... A hybrid coordinate ocean model (ltYCOM) is used to simulate the Kuroshio frontal eddies in the East China Sea (ECS). The research area is located (20°-32°N, 120°-132°E). Using tile simulating data, it is figured out that the Kuroshio frontal eddies occur in summer as well as in the other season in this area. The life cycle of the Kuroshio and its frontal eddies is different with the position. The life-cycle of the Kuroshio frontal eddies of the northwest Diaoyu Islands is about 14 d; and the life cycle of the Kuroshio frontal eddies of southwest Yakushima about 20 d. This result extends the in situ researching results greatly. In addition, the vertical impact depth of the Kuroshio frontal eddies is also changing with the position. On the whole, in the ECS, the maximum impact depth of the Kuroshio frontal eddies of the northwest Taiwan Islands is about 75 m; the maximum impact depth of the Kuroshio frontal eddies of the northwest Diaoyu Islands is more than 125 m, but no more than 200 m; and the maximum impact depth of the Kuroshio frontal eddies of southwest Yakushima is up to 100 m. 展开更多
关键词 Kuroshio frontal eddies hybrid coordinate ocean model East China Sea
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Phase Two of the Integrative Monsoon Frontal Rainfall Experiment(IMFRE-II)over the Middle and Lower Reaches of the Yangtze River in 2020 被引量:4
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作者 Chunguang CUI Xiquan DONG +1 位作者 Bin WANG Hao YANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2021年第3期346-356,共11页
Phase Two of the Integrative Monsoon Frontal Rainfall Experiment(IMFRE-II)was conducted over the middle and lower reaches of the Yangtze River during the period 16 June to 19 July 2020.This paper provides a brief over... Phase Two of the Integrative Monsoon Frontal Rainfall Experiment(IMFRE-II)was conducted over the middle and lower reaches of the Yangtze River during the period 16 June to 19 July 2020.This paper provides a brief overview of the IMFRE-II field campaign,including the multiple ground-based remote sensors,aircraft probes,and their corresponding measurements during the 2020 mei-yu period,as well as how to use these numerous datasets to answer scientific questions.The highlights of IMFRE-II are:(1)to the best of our knowledge,IMFRE-II is the first field campaign in China to use ground-based,airborne,and spaceborne platforms to conduct comprehensive observations over the middle and lower reaches of the Yangtze River;and(2)seven aircraft flights were successfully carried out,and the spectra of ice particles,cloud droplets,and raindrops at different altitudes were obtained.These in-situ measurements will provide a“cloud truth”to validate the ground-based and satellite-retrieved cloud and precipitation properties and quantitatively estimate their retrieval uncertainties.They are also crucial for the development of a warm(and/or cold)rain conceptual model in order to better understand the cloud-to-rain conversion and accretion processes in mei-yu precipitation events.Through an integrative analysis of ground-based,aircraft,and satellite observations and model simulations,we can significantly improve our cloud and precipitation retrieval algorithms,investigate the microphysical properties of cloud and precipitation,understand in-depth the formation and dissipation mechanisms of mei-yu frontal systems,and improve cloud microphysics parameterization schemes and model simulations. 展开更多
关键词 2020 mei-yu frontal systems IMFRE-II and its highlights Comprehensive observations from groundbased airborne and spaceborne platforms
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Improvements in Long-Lead Prediction of Early-Summer Subtropical Frontal Rainfall Based on Arctic Sea Ice 被引量:1
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作者 XING Wen HUANG Fei 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第3期542-552,共11页
Seasonal prediction of East Asia(EA) summer rainfall, especially with a longer-lead time, is in great demand, but still very challenging. The present study aims to make long-lead prediction of EA subtropical frontal r... Seasonal prediction of East Asia(EA) summer rainfall, especially with a longer-lead time, is in great demand, but still very challenging. The present study aims to make long-lead prediction of EA subtropical frontal rainfall(SFR) during early summer(May-June mean, MJ) by considering Arctic sea ice(ASI) variability as a new potential predictor. A MJ SFR index(SFRI), the leading principle component of the empirical orthogonal function(EOF) analysis applied to the MJ precipitation anomaly over EA, is defined as the predictand. Analysis of 38-year observations(1979-2016) revealed three physically consequential predictors. A stronger SFRI is preceded by dipolar ASI anomaly in the previous autumn, a sea level pressure(SLP) dipole in the Eurasian continent, and a sea surface temperature anomaly tripole pattern in the tropical Pacific in the previous winter. These precursors foreshadow an enhanced Okhotsk High, lower local SLP over EA, and a strengthened western Pacific subtropical high. These factors are controlling circulation features for a positive SFRI. A physical-empirical model was established to predict SFRI by combining the three predictors. Hindcasting was performed for the 1979-2016 period, which showed a hindcast prediction skill that was, unexpectedly, substantially higher than that of a four-dynamical models’ ensemble prediction for the 1979-2010 period(0.72 versus 0.47). Note that ASI variation is a new predictor compared with signals originating from the tropics to mid-latitudes. The long-lead hindcast skill was notably lower without the ASI signals included, implying the high practical value of ASI variation in terms of long-lead seasonal prediction of MJ EA rainfall. 展开更多
关键词 East Asia SUBTROPICAL frontal rainfall long-lead seasonal PREDICTION Arctic sea ice Physical-empirical model
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Synchronization between frontal eye field and area V4 during free-gaze visual search 被引量:1
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作者 Ting Yan Hui-Hui Zhou 《Zoological Research》 SCIE CAS CSCD 2019年第5期394-403,共10页
Information flow between the prefrontal and visual cortices is critical for visual behaviors such as visual search. To investigate its mechanisms, we simultaneously recorded spike and local field potential (LFP) signa... Information flow between the prefrontal and visual cortices is critical for visual behaviors such as visual search. To investigate its mechanisms, we simultaneously recorded spike and local field potential (LFP) signals in the frontal eye field (FEF) and area V4 while monkeys performed a free-gaze visual search task. During free-gaze search, spike-LFP coherence between FEF and V4 was enhanced in the theta rhythm (4–8 Hz) but suppressed in the alpha rhythm (8–13 Hz). Cross-frequency couplings during the Cue period before the search phase were related to monkey performance, with higher FEF theta-V4 gamma coupling and lower FEF alpha-V4 gamma coupling associated with faster search. Finally, feature-based attention during search enhanced spike-LFP coherence between FEF and V4 in the gamma and beta rhythms, whereas overt spatial attention reduced coherence at frequencies up to 30 Hz. These results suggest that oscillatory coupling may play an important role in mediating interactions between the prefrontal and visual cortices during visual search. 展开更多
关键词 SYNCHRONIZATION frontal eye field (FEF) V4 VISUAL SEARCH
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Energy Paths that Sustain the Warm-Sector Torrential Rainfall over South China and Their Contrasts to the Frontal Rainfall: A Case Study 被引量:2
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作者 Shenming FU Jingping ZHANG +2 位作者 Yali LUO Wenying YANG Jianhua SUN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第9期1519-1535,共17页
Predicting warm-sector torrential rainfall over South China,which is famous for its destructive power,is one of the most challenging issues of the current numerical forecast field.Insufficient understanding of the key... Predicting warm-sector torrential rainfall over South China,which is famous for its destructive power,is one of the most challenging issues of the current numerical forecast field.Insufficient understanding of the key mechanisms underlying this type of event is the root cause.Since understanding the energetics is crucial to understanding the evolutions of various types of weather systems,a general methodology for investigating energetics of torrential rainfall is provided in this study.By applying this methodology to a persistent torrential rainfall event which had concurrent frontal and warm-sector precipitation,the first physical image on the energetics of the warm-sector torrential rainfall is established.This clarifies the energy sources for producing the warm-sector rainfall during this event.For the first time,fundamental similarities and differences between the warm-sector and frontal torrential rainfall are shown in terms of energetics.It is found that these two types of rainfall mainly differed from each other in the lower-tropospheric dynamical features,and their key differences lay in energy sources.Scale interactions(mainly through downscale energy cascade and transport)were a dominant factor for the warm-sector torrential rainfall during this event,whereas,for the frontal torrential rainfall,they were only of secondary importance.Three typical signals in the background environment are found to have supplied energy to the warm-sector torrential rainfall,with the quasi-biweekly oscillation having contributed the most. 展开更多
关键词 torrential rainfall warm-sector rainfall frontal rainfall South China scale interactions baroclinic energy conversion
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Integrative Monsoon Frontal Rainfall Experiment(IMFRE-I):A Mid-Term Review 被引量:2
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作者 Chunguang CUI Xiquan DONG +3 位作者 Bin WANG Baike XI Yi DENG Yihui DING 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2021年第3期357-374,共18页
The mei-yu season,typically occurring from mid-June to mid-July,on average,contributes to 32%of the annual precipitation over the Yangtze-Huai River Valley(YHRV)and represents one of the three heavy-rainfall periods i... The mei-yu season,typically occurring from mid-June to mid-July,on average,contributes to 32%of the annual precipitation over the Yangtze-Huai River Valley(YHRV)and represents one of the three heavy-rainfall periods in China.Here,we briefly review the large-scale background,synoptic pattern,moisture transport,and cloud and precipitation characteristics of the mei-yu frontal systems in the context of the ongoing Integrative Monsoon Frontal Rainfall Experiment(IMFRE)field campaign.Phase one of the campaign,IMFRE-I,was conducted from 10 June to 10 July 2018 in the middle reaches of the YHRV.Led by the Wuhan Institute of Heavy Rain(IHR)with primary support from the National Natural Science Foundation of China,IMFRE-I maximizes the use of our observational capacity enabled by a suite of ground-based and remote sensing instruments,most notably the IHR Mesoscale Heavy Rainfall Observing System(MHROS),including different wavelengths of radars,microwave radiometers,and disdrometers.The KA350(Shanxi King-Air)aircraft participating in the campaign is equipped with Ka-band cloud radar and different probes.The comprehensive datasets from both the MHROS and aircraft instruments are combined with available satellite observations and model simulations to answer the three scientific questions of IMFRE-I.Some highlights from a previously published special issue are included in this review,and we also briefly introduce the IMFRE-II field campaign,conducted during June-July 2020,where the focus was on the spatiotemporal evolutions of the mei-yu frontal systems over the middle and lower reaches of the YHRV. 展开更多
关键词 mei-yu frontal system IMFRE-I IMFRE-II
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Combined effects of electroacupuncture and anti-depression drugs on the hippocampus and frontal lobe 被引量:1
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作者 Dongmei Duan Ya Tu +1 位作者 Shuang Jiao Liping Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第22期1723-1727,共5页
Electroacupuncture (EA) has been clinically used to treat depression and has resulted in favorable effects in China. However, results from animal studies and pathology do not reflect the influence of electroacupunct... Electroacupuncture (EA) has been clinically used to treat depression and has resulted in favorable effects in China. However, results from animal studies and pathology do not reflect the influence of electroacupuncture treatment on in vivo physiological functions. To thoroughly and dynamically observe pathological changes during depression, the present study established EA + fluoxetine and fluoxetine groups to observe depression in patients. 1H-magnetic resonance spectroscopy was utilized to determine the correlation between hippocampal frontal lobe metabolite changes and mental disorder scale. Results revealed significantly increased N-acetylaspartate (NAA)/creatine (Cr) in the bilateral hippocampus and right frontal lobe of depression patients treated with EA compared with fluoxetine. Changes in NAA/Cr in bilateral hippocampus and right frontal lobe in both groups, before and after treatment, negatively correlated with severity and curative effects. Choline/Cr changes in the bilateral frontal lobes of both groups were significant before and after treatment, but negatively correlated with curative effects. Choline/Cr changes in the bilateral hippocampus were significant in the EA + fluoxetine group before and after treatment, but negatively correlated with severity and the curative effects of depression. These results demonstrate abnormal biochemical metabolism in bilateral frontal lobes and hippocampus of depression patients, and show that EA significantly altered biochemical indices in the frontal lobes and hippocampus compared with fluoxetine. 展开更多
关键词 depression ELECTROACUPUNCTURE FLUOXETINE HIPPOCAMPUS frontal lobe traditional Chinese medicine magnetic resonance spectroscopy neural regeneration
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Detection of the Kuroshio frontal instable processes (KFIP) in the East China Sea using the MODIS images 被引量:1
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作者 JIA Yongjun ZHANG Jie 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2010年第6期35-43,共9页
The Kuroshio frontal instable processes (KFIP) in the East China Sea (ECS) not only have a great impact on the hydrologic characteristics,the pollutants drift,the distribution of seafloor sediment and the ships na... The Kuroshio frontal instable processes (KFIP) in the East China Sea (ECS) not only have a great impact on the hydrologic characteristics,the pollutants drift,the distribution of seafloor sediment and the ships navigation of the ECS,but also are closely related to the climate changes of the coastal areas of the ECS.However the frequency and area of occurrence of the KFIP have not been studied fully and detailedly.Because of its high spatial and temporal resolution,MODIS data is a kind of very good data source for surveying and researching the KFIP in the ECS.The aim of this study is to detect the KFIP in the ECS by using MODIS data,and to study the frequency and region of occurrence of the KFIP in the ECS.The selection has coverage of level 2 data of MODIS SST and Kd490 ranging from July 1,2002 to June 30,2009 of the ECS when there was no cloud impact or little.By using of the data,the minimum standard of the Kuroshio temperature fronts and the diffuse attenuation coefficient (Kd490) fronts of the ECS are given.Based on these standards and the curvature distinguish methods,the standard of curvature distinguish for the KFIP in the ECS are put forward.By making use of this standard,we study a total of 2073 satellite-derived images,and discover that as long as there is no cloud impact from January to May and October to December,the KFIP in the ECS are surely found in MODIS satellite images.From June to September,the frequency of occurrence can also reach to 82.9% at least.Moreover,it is obtained that there are three source regions of these instability processes,namely,(26°N,121.5°E) nearby,(27°N,125°E) nearby and (30°N,128°E) nearby.The differences of the characteristics of these instability processes which are generated in different regions are analyzed in the present study. 展开更多
关键词 Kuroshio frontal instable processes frequency and region of occurrence East China Sea MODIS
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