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Occurrence of double parasitism on black-barred halfbeak fish from the southeast coast of India

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Chinese Journal of Oceanology and Limnology 2010年第4期28卷 832-835页

作者： A.GOPALAKRISHNAN M.RAJKUMAR 孙军 J.P.TRILLES Centre of Advanced Study in Marine Biology Annamalai University Institute of Oceanology Chinese Academy of Sciences Equipe Adaptation Ecophysiologique et Ontogenèse UMR 5119 ECOLAG(CNRS-UM2-IFREMER)Université de Montpellier ⅡSciences et Techniques du Languedoc

A double parasitism(isopod Cymothoidae and copepod Pennellidae) on black-barred halfbeak fish,Hemiramphus far,was recorded from Pazhayar coastal waters(southeast coast of India) during September *** is the first repor... 详细信息

关键词： Isopod Copepod double parasitism Hemiramphus far

Piecewise Smooth Dynamical Systems Modeling Based on Putzer and Fibonacci-Horner Theorems:DC-DC Converters Case

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International Journal of Automation and computing 2016年第3期13卷 246-258页

作者： Abdelkader Khoudiri Kamel Guesmi Djillali Mahi Department of sciences and techniques Djelfa University CRe STIC IUT de Troyes

The paper deals with the problem of switched dynamical systems modeling especially in DC-DC converters case study consideration. It presents two approaches to describe accurately the behavior of this class of systems. To clarify the paper＇s contribution, the proposed approaches are validated through simulations and experimental results. A comparative study, between the obtained results and those of other techniques from the literature, is given to evaluate the performances of the studied approaches.

关键词： Switched systems DC-DC converters modeling Cayley-Hamilton theorem Putzer's theorem Fibonacci-Horner decom-position theorem.

Preliminary study of depth of interaction measurement for a Pet detector

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Chinese Physics C 2011年第11期35卷 1070-1073页

作者：廖燕飞章志明李道武帅磊单保慈黄先超刘军辉陈研王英杰刘双全王培林魏书军魏龙 Key Laboratory of Nuclear Analysis techniques Institute of High Energy PhysicsChinese Academy of Sciences Beijing Engineering Research Center of Radiographic techniques and Equipment Graduate University of Chinese Academy of sciences

In this work we studied the feasibility of detecting the depth of interaction （DOI） with two layers of crystal arrays of LYSO and BGO scintillators coupled to a position-sensitive photomultiplier tube （PS-PMT） R8900-C12. A front-end electronics was designed, with which we got different pulse shapes for different crystals to obtain depth information. With the double integration method, we got the DOI histogram of a divided integration ratio of two crystals as the standard to determine the layer-of-interaction. The DOI accuracy, measured by scanning a 22Na slit source along the side of the module, was 98% for the LYSO layer and 95% for the BGO layer. The energy resolution at 511keV was 13.1% for LYSO and 17.1% for BGO. We obtained good crystal separation in 2D position histograms of both layers. These results could be useful in the manufacture of Pet scanners with high spatial resolutions.

关键词： Pet detector DOI spatial resolution

Sperm limitation affects sex allocation in a parasitoid wasp Nasonia vitripennis

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Insect Science 2019年第5期26卷 853-862页

作者： Marlene Chirault Christophe Bressac Marlene Goubault Charlotte Lecureuil Institut de Recherche sur la Biologie de I'lnsecte UMR 7261 CNRS - Universite de ToursFaculte des Sciences et TechniquesParc GrandmontToursFrance

Insect reproduction is influenced by various external factors including temperature, a well-studied constraint. We investigated to what extent different levels of sperm limitation of males exposed to different heat stresses (34 and 36℃) afFect fem ales' offspring production and sex allocation in Nasonia vitripennis. In this haplodiploid parasitoid wasp attacking different species of pest flies, we investigated the effect of the quantity of sperm females received and stored in their spermatheca on their sperm use decisions, hence sex allocation, over successive ovipositions. In particular, we compared the sex allocation of females presenting three levels of sperm limitation (i.e.,mated with control, 34 ℃ heat-stressed or 36℃heat-stressed males) on each host they parasitized. To disentangle the potential reduction of sperm quality after a heat stress exposure from that of sperm quantity, we also explored the clutch size and sex ratio produced by fem ales that were partially sperm limited after copulating with multiply mated males. Independently of their sperm numbers, all types of fem ales produced a similar total number of offspring, but the more limited ones had fewer daughters. Sperm limitation further affected the distribution of daughters' production across *** addition to constraints acting on female physiology, male fertility should therefore be considered in studies measuring reproductive outputs of insects submitted to heat stresses.

关键词： heat stress multiple mating offspring production dynamic sex ratio sperm stock sperm use

Performance evaluation of a parallel-hole collimated detector module for animal SPECT imaging

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Chinese Physics C 2011年第12期35卷 1162-1165页

作者：黄先超章志明李道武唐浩辉李婷廖燕飞刘军辉王培林陈研王英杰魏龙单保慈王宝义 Key Laboratory of Nuclear Analytical techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing Engineering Research Center of Radiographic techniques and Equipment Graduate University of Chinese Academy of sciences

We have built and investigated a detector module for animal SPECT imaging, especially for use in large field of view （FOV） conditions. The module consists of a PMT-based detector and a parallel-hole collimator with an effective area of 80 mm× 80 mm. The detector is composed of a NaI scintillation crystal array coupled to four H8500 position sensitive photomultiplier tubes （PS-PMT）. The intrinsic energy resolution of the detector is 11.5% at 140 keV on average. The planar spatial resolution of the module changes from 2.2 mm to 5.1 mm at different source-to-collimator distances with an unchanged sensitivity of about 34cps/MBq. Additionally, the SPECT Micro Deluxe Phantom imaging was performed with a radius of rotation （ROR） of 40 mm. Using the FBP reconstruction algorithm, a high performance image was obtained, indicating the feasibility of this detector module.

关键词： animal imaging SPECT parallel-hole collimator

Hypolipidemic activity of Tamarix articulata Vahl. in diabetic rats

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Journal of Integrative Medicine 2017年第6期15卷 476-482页

作者： morad hebi mohamed eddouks faculty of sciences and techniques errachidia moulay ismail universityBoutalamine52000 Errachidia Morocco

OBJECTIVE： Tamarix articulata Vahl. （Tamaricaceae） is a medicinal plant commonly used in Morocco for the treatment of diabetes mellitus and cardiovascular diseases. The objective of this study was to evaluate the hypolipidemic activity of aqueous extract of T. articulata in normal and streptozotocin （STZ）-induced diabetic rats. Phytochemical analysis as well as determination of polyphenol and flavonoid contents in the aqueous extract of T. articulata was performed. MetHODS： The effects of oral administration of aqueous extract of T. articulata （5 mg/kg） on the plasma total cholesterol, triglyceride and high-density lipoprotein cholesterol （HDL-c） concentrations were measured in both normal and STZ-induced diabetic rats. Total phenolic content of the aqueous extract was determined by Folin-Ciocalteu method. In addition, determination of flavonoid content was performed using colorimetric AICI3 method. RESULTS： A single oral administration in diabetic rats induced a significant increase in the HDL-c concentration after 6 h of treatment with T. articulata （5 mg/kg）. The results also demonstrated that the aqueous extract of T. articulata produced a significant decrease of serum total cholesterol after repeated oral administration in diabetic rats （P 〈 0.01）. The total polyphenol and flavonoid contents of T. articulata aqueous extract were equal to 102.50 mg of gallic acid equivalent per gram of extract and 54.83 mg of quercetin equivalent per gram of extract, respectively. CONCLUSION： According to preliminary phytochemical screening of the aerial part of T. articulata, severa classes of chemicals have been found, such as polyphenols, flavonoids, tannins, cyanidins （flavones, catechols）, mucilage, sesquiterpenes, terpenoids and carbohydrates. In conclusion, T. articulata exhibits a hypolipidemic effect in diabetic rats and its beneficial role as hypolipidemic agent should be evaluated in clinical studies.

关键词： hypolipidemic streptozotocin total cholesterol triglycerides flavonoids

Enteric parasites prevalence at Saint Camille Medical Centre in Ouagadougou,Burkina Faso

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Asian Pacific Journal of Tropical Medicine 2011年第5期4卷 401-403页

作者： Simplice Damintoti Karou Drissa Sanou Djeneba Ouermi Salvatore Pignatelli Virginio Pietra Remy Moret Jean Baptiste Nikiema Jacques Simpore Centre de Recherche Biomoleculaire Pietro Annigoni(CERBA) OuagadougouBurkina Faso Ecole Superieure des techniques Biologiques et Alimentaires(RSTBA-UL) Universite de LomeTogo Unite de Formation et de Recherche en sciences de la Vie et de la Terre(ufr/SVT) Universite de OuagadougouBurkina Faso Centre medical saint Camille de Ouagadougou Burkina Faso

Objective:To assess the prevalence of parasitic infections among patients attending Saint Camille Medical Centre and to estimate co-parasitic infections ***:From January to December 2009,stool samples were collected from 11 728 persons,aged from five months to 72 years and suffering from *** macroscopic description,the stools were examined by light microscopy to search for the presence of ***:From the 11 728 analyzed stools,6 154(52.47%) were infected with at least one *** frequently encountered were:Giardia intestinalis(43.47%),Entamoeba histolytica/Entamoeba dispar(30.74%) and Trichomonas irUestinalis(21.72%),while Hymenolepis nana(2.25%) was the most common ***-infections occurred in 22.34%*** the multi-infected samples,dual and triple infections accounted for 71.18%and 20.00%,*** irUestinalis for protozoan and Hymenolepis nana for helminths were the most implicated ***: This study confirms that intestinal parasites are still a public health problem in Burkina *** reduce the incidence of parasitic infections,it is necessary to promote the education of people so that they practice the rules of individual and collective hygiene.

关键词： Gastroenteritis Giardia intestinalis Hymenolepis nana Helminths Burkina Faso

Effect of Feature Selection on the Prediction of Direct Normal Irradiance

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Big Data Mining and Analytics 2022年第4期5卷 309-317页

作者： Mohamed Khalifa Boutahir Yousef Farhaoui Mourade Azrour Imad Zeroual Ahmad El Allaoui Faculty of sciences and techniques Moulay Ismail UniversityErrachidia 52000Morocco

Solar radiation is capable of producing heat,causing chemical reactions,or generating ***,the amount of solar radiation at different times of the day must be determined to design and equip all solar ***,it is necessary to have a thorough understanding of different solar radiation components,such as Direct Normal Irradiance(DNI),Diffuse Horizontal Irradiance(DHI),and Global Horizontal Irradiance(GHI).Unfortunately,measurements of solar radiation are not easily accessible for the majority of regions on the *** paper aims to develop a set of deep learning models through feature importance algorithms to predict the DNI *** proposed models are based on historical data of meteorological parameters and solar radiation properties in a specific location of the region of Errachidia,Morocco,from January 1,2017,to December 31,2019,with an interval of 60 *** findings demonstrated that feature selection approaches play a crucial role in forecasting of solar radiation accurately when compared with the available data.

关键词： machine learning deep learning feature importance renewable energies solar radiation

Design of data acquisition system and algorithm research for omnidirectional gamma-ray positioning equipment

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Chinese Physics C 2014年第1期38卷 89-93页

作者：胡婷婷帅磊王培林丰宝桐张译文孙芸华李晓辉魏书军单保慈魏龙 Key Laboratory of Nuclear Analysis techniques Institute of High Energy PhysicsChinese Academy of Sciences Beijing Engineering Research Center of Radiographic techniques and Equipment

This article introduces the design and performance of the data acquisition system used in an omnidi- rectional gamma-ray positioning system, along with a new method used in this system to obtain the position of radiation sources in a large field. This data acquisition system has various built-in interfaces collecting, in real time, information from the radiation detector, the video camera and the GPS positioning module. Experiments show that the data acquisition system is capable of carrying out the proposed quantitative analysis to derive the position of radioactive sources, which also satisfies the requirements of high stability and reliability.

关键词： gamma-ray positioning data acquisition FPGA