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Engineering（科研） 2021年第1期13卷 56-70页

作者： jean-marie Kadjo Raoule Agoua Aliou Bamba Adama Konaté Olivier Asseu LASTIC ESATIC Abidjan C&#244 te d’Ivoire

This paper addresses the problem of the opportunistic spectrum access in Cognitive Radio. Indeed, most spectrum sensing algorithms suffer from a high computational cost to achieve the detection process. They need a prior knowledge of signal characteristics and present a bad performance in low Signal to Noise Ratio (SNR) environment. The choice of the optimal detection threshold is another issue for these spectrum sensing algorithms. To overcome the limits of spectrum detectors, we propose in this paper, a blind detection method based on the cyclostationary features of communication signals. Our detector evaluates the level of hidden periodicity contained in the observed signal to make decision on the state of a bandwidth. In order to reduce the computational cost, we take advantage of the FFT Accumulation Method to estimate the cyclic spectrum of the observed signal. Then, we generate the Cyclic Domain Profile of the cyclic spectrum which allows us to evaluate the level of the hidden periodicity in the signal. This level of periodicity is quantified through the crest factor of Cyclic Domain Profile, which represents the decision statistic of the proposed detector. We have established the analytic expression of the optimal threshold of the detection and the probability of detection to evaluate the performance of the proposed detector. Simulation results show that the proposed detector is able to detect the presence of a communication signal on a bandwidth in a very low SNR scenario.

关键词： Spectrum Sensing Cyclostaionarity FFT Accumulation Method Cyclic Spectrum Spectrum Coherence Cognitive Radio

An Optimal Weight Method for CT Image Denoising

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Journal of Electronic Science and Technology 2012年第2期10卷 124-129页

作者： Dinh Hoan Trinh marie Luong jean-marie Rocchisani Canh Duong Pham Huy Dien Pham Francoise Dibos the LAGA Laboratory Université Paris 13 Sorbonne Paris CitéF-93430 Villetaneuse France the L2TI Laboratory Université Paris 13 Sorbonne Paris CitéF-93430 Villetaneuse France the Hopital Avicenne-Medicine Nucleaire the CIID Laboratory Vietnam Academy of Science and Technology

This paper proposes a novel exemplar- based method for reducing noise in computed tomography （CT） images. In the proposed method, denoising is performed on each block with the help of a given database of standard image blocks. For each noisy block, its denoised version is the best sparse positive linear combination of the blocks in the database. We formulate the problem as a constrained optimization problem such that the solution is the denoised block. Experimental results demonstrate the good performance of the proposed method over current state-of-the-art denoising methods, in terms of both objective and subjective evaluations.

关键词： Constrained quadratic programming computed tomography image exemplar-based denoising.

Actigraphy: A new diagnostic tool for hepatic encephaiopathy

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World Journal of Gastroenterology 2006年第14期12卷 2243-2244页

作者： Isabelle Hourmand-Ollivier marie-Astrid Piquet jean Pierre Toudic Pierre Denise Thng Dao Department of Nutrition and Hepatogastroenterology CHU Cte de Nacre-14033 cedex Caen France Physiology Laboratory CHU Cte de Nacre-14033 cedex Caen France

AIM： To assess the actigraphy, an ambulatory and continuous monitoring of wrist motor activity fitted to study sleep/wake patterns in hepatic encephalopathy （HE）. METHODS： Twenty-five cirrhotic patients （17 M, 8 F, mean age 56± 11 years, 24/25 alcoholic, Child-Pugh A, B, C： 2, 6, 17） were included. The patients were classified into 3 groups： stage 0 group （n = 12）, stage 1-2 group （n = 6）, and stage 3-4 group （n = 7） of encephalopathy. Over three consecutive days, patients had clinical evaluation 3 times a day with psychometric test, venous ammoniemia, flash visually evoked potentials （VEP）, electroencephalogram and continuous actigraphic monitoring for 3 d, providing 5 parameters： mesor, amplitude, acrophase, mean duration of activity （MDAI） and inactivity （MDII） intervals. RESULTS： Serum ammonia and VEP did not differ among the 3 groups. Electroencephalography mean dominant frequency （MDF） correlated significantly with clinical stages of HE （r=0.65, P=0.003）. The best correlation with HE stage was provided by actigraphy especially with MDAI （r= 0.7, P〈10^-4） and mesor （r= 0.65, P〈 10^-4）. MDAI correlated significantly with MDF （r= 0.62, 0.004） and was significantly shorter in case of HE compared to patients without HE （stage 0： 5.33± 1.6 min; stage 1-2：3.28±1.4 min; stage 3-4：2.52±1.1 min; P〈0.05）. Using a threshold of MDAI of less than 4.9 min, sensitivity, specificity, positive predictive value, negative predictive value for HE diagnosis were 85%, 67%, 73% and 80%, respectively. CONCLUSION： Actigraphy may be an objective method to identify HE, especially for early HE detection. Motor activity at the wrist correlates well with clinical stages of HE. MDAI and mesor are the most relevant parameters.

关键词： Hepatic encephalopathy Cirrhosis Actigraphy

Gender influence on defecographic abnormalities in patients with posterior pelvic floor disorders

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World Journal of Gastroenterology 2010年第4期16卷 462-466页

作者： Céline Savoye-Collet Guillaume Savoye Edith Koning Anne-marie Leroi jean-Nicolas Dacher Radiology Department QUANT-IF LITIS EA 4108Rouen University Hospital Charles Nicolle1 rue de GermontF76031 RouenFrance Gastroenterology Department ADEN EA 4311Rouen University Hospital Charles Nicolle1 rue de GermontF-76031 RouenFrance Physiology Department ADEN EA 4311Rouen University Hospital Charles Nicolle1 rue de GermontF-76031 RouenFrance

AIM:To compare defecographic abnormalities in symptomatic men and women and to analyze differences between men and age-and symptom-matched ***:Sixty-six men(mean age:55.4 years,range:20-81 years) who complained of constipation and/or fecal incontinence and/or pelvic pain underwent defecography after intake of a barium *** were analyzed for the diagnosis of rectocele,enterocele,intussusception and perineal *** were compared with age-and symptom-matched women(n = 198) who underwent defecography during the same ***:Normal defecography was observed in 22.7% of men vs 5.5% of women(P < 0.001).Defecography in men compared with women showed 4.5%vs 44.4%(P < 0.001) rectocele,and 10.6% vs 29.8%(P < 0.001) enterocele,*** difference was observed for the diagnosis of intussusception(57.6% vs 44.9%).Perineal descent at rest was more frequent in women(P < 0.005).CONCLUSION:For the same complaint,diagnosis of defecographic abnormalities was different in men than in women:rectocele,enterocele and perineal descent at rest were observed less frequently in men than in women.

关键词： Fecal incontinence Defecography Rectocele Hernia Pelvic floor Constipation

Assessment of Phytosanitary Practices in Peri-Urban Agriculture and Associated Environmental and Health Impacts in Developing Countries: Case of Abengourou City (Côte d’Ivoire)

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Journal of Agricultural Chemistry and Environment 2021年第3期10卷 275-288页

作者： jean-marie Pétémanagnan Ouattara Franck Michaël Zahui jean Rufin Kouassi Kouame Lacina Coulibaly Department of Sciences and Environment Management Nangui Abrogoua University Abidjan C&ocirc te d’Ivoire Department of Agronomic Forestry and Environmental Engineering University of Man Man C&ocirc te d’Ivoire

The use of phytosanitary products remains uncontrolled and abusive in the practice of market gardening in most developing countries. However, it remains one of the potential sources of environmental contamination and public health problems. This study examines the health and environmental risks associated with the use of phytosanitary products in market gardening in the town of Abengourou in Cote d’Ivoire. Field surveys carried out among all (30) market gardener sites housed 150 farmers showed that when the products were spread, no health and safety measures were observed. Approximately 80% of the respondents did not wear gloves or face masks. Some products used were not approved for market gardening. Farmers had itching, dizziness, headaches, colds and vomiting on a regular basis when applying the products. The study also revealed the presence of empty packaging in the surrounding surface water and on the ground. In addition to producers, this type of uncontrolled market gardening likely exposes consumers to high health risks and also contributes to environmental degradation. Raising awareness among stakeholders of good agricultural practices could help promote sustainable market gardening. However, studies of the effects of products in such an environment on the health of consumers deserve to be carried out.

关键词： Phytosanitary Practices Market Gardening Health and Environmental Risks Abengourou City Côte d’Ivoire

Ancient migration routes of Austronesian-speaking populations in oceanic Southeast Asia and Melanesia might mimic the spread of nasopharyngeal carcinoma

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Chinese Journal of Cancer 2011年第2期30卷 96-105页

作者： jean Trejaut Chien-Liang Lee Ju-Chen Yen Jun-Hun Loo marie Lin Mackay Memorial Hospital #45 Min-Sheng Road

Mitochondrial DNA (mtDNA) and non-recombining Y chromosome (NRY) are inherited uni-parentally from mother to daughter or from father to son respectively. Their polymorphism has initially been studied throughout populations of the world to demonstrate the "Out of Africa" hypothesis. Here, to correlate the distribution of nasopharyngeal carcinoma (NPC) in different populations of insular Asia, we analyze the mtDNA information (lineages) obtained from genotyping of the hyper variable region (HVS I & II) among 1400 individuals from island Southeast Asia (ISEA), Taiwan and Fujian and supplemented with the analysis of relevant coding region polymorphisms. Lineages that best represented a clade (a branch of the genetic tree) in the phylogeny were further analyzed using complete genomic mtDNA sequencing. Finally, these complete mtDNA sequences were used to construct a most parsimonious tree which now constitutes the most up-to-date mtDNA dataset available on ISEA and Taiwan. This analysis has exposed new insights of the evolutionary history of insular Asia and has strong implications in assessing possible correlations with linguistic, archaeology, demography and the NPC distribution in populations within these regions. To obtain a more objective and balanced genetic point of view, slowly evolving biallelic Y single nucleotide polymorphism (Y-SNP) was also analyzed. As in the first step above, the technique was first applied to determine affinities (macro analysis) between populations of insular Asia. Secondly, sixteen Y short tandem repeats (Y-STR) were used as they allow deeper insight (micro analysis) into the relationship between individuals of a same region. Together, mtDNA and NRY allowed a better definition of the relational, demographic, cultural and genetic components that constitute the make up of the present day peoples of ISEA. Outstanding findings were obtained on the routes of migration that occurred along with the spread of NPC during the settlement of insular

关键词：世界人口迁徙路线鼻咽癌单核苷酸多态性线粒体DNA 东南亚全国人民代表大会短串联重复序列

Vorticity effects in drop impact

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Vorticity effects in drop impact

Value of intravascular ultrasound imaging in following up patients with replacement of the ascending aorta for acute type A aortic dissection

第九届全国流体力学学术会议

作者： marie-jean THORAVAL Sigurdur T.THORODDSEN International Center for Applied Mechanics State Key Laboratory for Strength and Vibration of Mechanical StructuresXi'an Jiaotong University Division of Physical Sciences and Engineering & Clean Combustion Research Center King Abdullah University of Science and Technology(KAUST)

The impact of drop on a liquid pool can entrap bubbles and splash smaller *** bubbles can dissolve and transfer gas into the pool,while the droplets can generate *** studies on drop impacts have neglected the effect of vorticity on the *** were able to reproduce the large scale dynamics of the drop entering the ***,recent results have demonstrated that the vorticity produced at the air-liquid interface plays a critical role in explaining the complex dynamics of splashing and air *** focus here on the dynamics of the air bubble entrapped just after contact between the drop and the *** show the role of vorticity in producing a large range of different bubble shape,including toroidal bubbles,and bubbles containing a liquid droplet

关键词： Drop impact Air Entrapment Splashing Vorticity Vortex Ring

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Chinese Medical Journal 2008年第21期121卷 2139-2143页

作者： HU Wei Francois Schiele Nicolas Meneveau marie-France Seronde Pierre Legalery Fiona Caulfield jean-Frangois Bonneville Sidney Chocron jean-Pierre Bassand Department of Cardiology Min Hang Central Hospital Shanghai 201100 China Department of Cardiology Jean Minjoz Hospital Besancon 25000 France Department of Radiology Jean Minjoz Hospital Besancon 25000 France Department of Cardiac Surgery Jean Minjoz Hospital Besancon 25000 France

Background The value of intravascular ultrasound （IVUS） imaging in patients with replacement of the ascending aorta for acute type A aortic dissection （AD） is unknown. The purpose of this study was to assess the potential use of IVUS imaging in this setting. Methods From September 2002 to July 2005, IVUS imaging with a 9 MHz probe was performed in a series of 16 consecutive patients with suspected or established AD. This study focused on 5 of them with replacement of the ascending aorta for acute type A AD. Among these 5 patients, other imaging modalities including aortography, spiral computed tomography, magnetic resonance imaging and transesophageal echocardiography were performed in 5, 3, 3 and 1 patients, respectively. Results There were no complications related to IVUS imaging. For the replaced graft, as other imaging modalities, IVUS could identify all 5 grafts, the proximal and the distal anastomoses, and the ostia of the reimplanted coronary arteries. In 2 cases, IVUS detected 2 peri-graft pseudo-aneurysms （1 per case）, which were also detected by magnetic resonance imaging but omitted by aortography. For the residual dissection, IVUS had similar findings as other imaging modalities in detecting the patency （5/5）, the longitudinal and the circumferential extent, the thrombus （4/5）, the recurrent dissection （1/5） and an aneurysm distal to the graft （5 in 4 patients）. However, it detected more intimal tears and side branch involvements than other imaging modalities （15 vs 10 and 3 vs 1, respectively）. Conclusions In following-up patients with replacement of the ascending aorta for acute type A AD, IVUS imaging can provide complete information of the replaced graft and the residual dissection. So, IVUS imaging may be considered when the four current frequently used imaging modalities can not supply sufficient information or there are some discrepancies between them.

关键词： intravascular ultrasound aortic dissection graft

Displacement Talbot lithography for nanoengineering of III-nitride materials

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Microsystems & Nanoengineering 2019年第1期5卷 38-49页

作者： Pierre-marie Coulon Benjamin Damilano Blandine Alloing Pierre Chausse Sebastian Walde Johannes Enslin Robert Armstrong Stephane Vezian Sylvia Hagedorn Tim Wernicke jean Massies Jesus Zuniga‐Perez Markus Weyers Michael Kneissl Philip A.Shields Department of Electrical&Electronic Engineering University of BathBath BA27AYUK Universite Cote d’Azur CNRSCRHEArue B.Gregory06560 ValbonneFrance Ferdinand-Braun-Institut Leibniz-Institut fur HochstfrequenztechnikGustav-Kirchhoff-Str.412489 BerlinGermany Technische Universität Berlin Institute of Solid State Physics10623 BerlinGermany

Nano-engineering III-nitride semiconductors offers a route to further control the optoelectronic properties,enabling novel functionalities and *** a variety of lithography techniques are currently employed to nanoengineer these materials,the scalability and cost of the fabrication process can be an obstacle for large-scale *** this paper,we report on the use of a fast,robust and flexible emerging patterning technique called Displacement Talbot lithography(DTL),to successfully nano-engineer III-nitride ***,along with its novel and unique combination with a lateral planar displacement(D^(2)TL),allow the fabrication of a variety of periodic nanopatterns with a broad range of filling factors such as nanoholes,nanodots,nanorings and nanolines;all these features being achievable from one single *** illustrate the enormous possibilities opened by DTL/D2TL,dielectric and metal masks with a number of nanopatterns have been generated,allowing for the selective area growth of InGaN/GaN core-shell nanorods,the top-down plasma etching of III-nitride nanostructures,the top-down sublimation of GaN nanostructures,the hybrid top-down/bottom-up growth of AlN nanorods and GaN nanotubes,and the fabrication of nanopatterned sapphire substrates for AlN *** with their planar counterparts,these 3D nanostructures enable the reduction or filtering of structural defects and/or the enhancement of the light extraction,therefore improving the efficiency of the final *** results,achieved on a wafer scale via DTL and upscalable to larger surfaces,have the potential to unlock the manufacturing of nano-engineered III-nitride materials.

关键词： Talbot planar nitride

Epidemiological Profile of Abnormal Uterine Bleeding at the Gyneco-Obstetric and Pediatric Hospital of Yaounde

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Open Journal of Obstetrics and Gynecology 2020年第2期10卷 237-242页

作者： Kasia jean marie Noa Ndoua Claude Cyrille Belinga Etienne Foumane Pascal Faculty of Medicine and Biomedical Sciences University of Yaounde I Yaounde Cameroon Gynaecological Endoscopic Surgery and Human Reproduction Teaching Hospital Yaounde Cameroon Gyneco-Obstetric and Pediatric Hospital of Yaounde Yaounde Cameroon

Introduction:?Abnormal uterine bleeding (AUB) is one of the most commonly encountered symptoms in gynecological consultations. The prognosis is rarely endangered but the impact on the quality of life is sometimes important. Objective:?Our objective was to assess the epidemiological profiles of patients consulting for AUB at the Yaounde Gyneco-Obstetrics and Pediatrics Hospital.?Methodology:?We carried out a descriptive cross-sectional study at the Yaounde Gyneco-Obstetrics and Pediatrics Hospital. We included all women with acute or chronic per vaginal bleeding and we excluded all cases of bleeding in pregnancy, bleeding due to infection, pre pubertal bleeding and the incomplete files. Data were?collected from January to May 2019, using a questionnaire, and analyzed using Epi Info version 3.5.4 and SPSS version 7. softwares. Results:?A total of 163 patient files were exploited and analyzed. The frequency of AUB in outpatient gynaecology clinics was 3.7%. AUB patients had a mean age of 36 ± 12.27 years and the most represented age group was 30 to 35 years, with 17.1% cases. Sixty-seven representing 41.1% patients were married, 23.9% were civil servants, 23.1% were tertiary employees, and 40.3% had secondary level of education. Almost 44.1% were nulliparous and 53.9% had unknown HIV status an 83.4% have never used contraception. Conclusion:?The frequency of AUB during gynecological consultations is 3.7%. Those women have an average age of 36 years, most of them are nulliparous and have never use contraception.

关键词： Morbidity Menstrual Cycle Abnormal Uterine Bleeding