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Inventory of Host Plants and Parasitoids of the Fall Armyworm (FAW), Spodoptera frugiperda (JE Smith), in the Southern Agricultural Zone of Niger

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Journal of Agricultural Chemistry and Environment 2023年第1期12卷 16-27页

作者： Ousmane Zakari Moussa Souleymane Laminou Hamissou Zangui Laouali Amadou Ibrahim Baoua Boukari Faculty of Agronomy Abdou Moumouni University of Niamey Niamey Niger Faculty of Agronomy and Environmental Sciences Dan Dicko Dankoulodo University of Maradi Maradi Niger laboratoire d’entomologie ii de maradi Institut National de la Recherche Agronomique du Niger Maradi Niger

The fall armyworm, Spodoptera frugiperda (JE Smith), is a polyphagous pest reported in sub-Saharan Africa since 2016 and has expanded rapidly in almost Africa. In Niger, Spodoptera frugiperda (JE Smith) is considered like a major pest of maize, to which it causes significant damage, in a context where proven control methods against this moth remain almost non-existent. The objective of the present study was to determine the economic importance of FAW through the damage caused to the different host plants and to identify the parasitoids of this caterpillar. The study was conducted in the southern agricultural zone of Niger, specifically in the regions of dosso, maradi, Tahoua and Zinder. FAW eggs and caterpillars were collected from six villages in each region and then incubated and reared in the entomology laboratory of INRAN in maradi. The rate of infestation of the different crops by FAW was determined as well as the observation of the beneficiaries. The results obtained indicate the presence of FAW on millet with an attack rate varying from 45.7% to 68%, sorghum with 47.2% to 62.25% and sesame with 9.7%. This work also revealed an oophagous parasitoid, Telenomus remus with 138 ± 23 and larval parasitoids, Cotesia sp with 16 ± 1 maximum number of individuals emerged from the collected material. Also, it was identified the parasitoid Cotesia icipe with a rate of parasitism from 4.6% to 5.75%;the Charops ater whose rate of parasitism varies from 4.5% and 12.25% but for Chelonus insularis with 17.25% and Tachnidae with 53%. These very interesting results will constitute a basis for the development of biological control and a component of an agroecological management strategy of caterpillar.

关键词： Inventory Host Plants Spodoptera frugiperda Parasitoids Niger

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Perception and Level of Knowledge of the Fall Armyworm (Spodoptera frugiperda J.E. Smith) by Maize Farmers in the Southern Agricultural Zone of Niger

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Agricultural Sciences 2022年第12期13卷 1321-1333页

作者： Souleymane Laminou Zakari Moussa Ousmane Laouali Amadou Mahaman Moctar Rabe Ibrahim Baoua Boukari Faculty of Agronomy and Environmental Sciences Dan Dicko Dankoulodo University of Maradi Maradi Niger Faculty of Agronomy Abdou Moumouni University of Niamey Niamey Niger laboratoire d’entomologie ii de maradi Institut National de la Recherche Agronomique du Niger Maradi Niger department of Agroeconomics and Rural Sociology University of Tahoua Tahoua Niger

Maize is one of the cereals most consumed by households in Niger. Its production remains marginal despite the efforts made in hydro-agricultural development both around the Niger River and in the interior of the country. The detection of the fall armyworm (Spodoptera frugiperda J.E. Smith) in 2016 in Niger, followed by its rapid spread where in less than a year it has spread over almost the entire national territory is not without consequence on the yields of the but already very low in the main production areas. As a result, maize production is increasingly being abandoned in the southern agricultural zone of Niger. In fact, this caterpillar has become a major pest of maize because of the significant damage observed on this crop during its growth and development cycle. This situation calls for research to be conducted to help maize producers better manage this pest. The objective of this study is to assess the level of knowledge and management of FAW by maize farmers in the southern agricultural zone of Niger. A survey was conducted in July and August 2020 on a sample of 408 farmers in this zone using an individual questionnaire designed and integrated into the OdK data collection software. The results obtained showed that 93% of the producers recognize FAW through its morphology and the aspects of its damage;53.25% estimate that the attack rate is very high and 60.75% of the producers use pesticides in the management of this pest against only 1.5% who use biopesticides. These results clearly indicate the severity of FAW attacks on corn and the massive use of pesticides by producers.

关键词： Fall Armyworm Perception Producer Incidence Niger

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Fermat and Pythagoras divisors for a New Explicit Proof of Fermat’s Theorem:a⁴ + b⁴ = c⁴. Part I

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Advances in Pure Mathematics 2024年第4期14卷 303-319页

作者： Prosper Kouadio Kimou François Emmanuel Tanoé Kouassi Vincent Kouakou laboratoire d’ Informatique et de Math&#233matiques appliqu&#233es Institut Polytechnique F&#233lix Houphou&#235t BOIGNY Yamoussoukro Cote d&#8217Ivoire UFR Mathé matiques et Informatique Universit&#233 F&#233lix Houphouet BOIGNY Abidjan Cote d&#8217Ivoire UFR Sciences Fondamentales Appliqué es Universit&#233 NANGUI ABROGOUA Abidjan Cote d&#8217Ivoire

In this paper we prove in a new way, the well known result, that Fermat’s equation a4 + b4 = c4, is not solvable in ℕ , when abc≠0 . To show this result, it suffices to prove that: ( F 0 ): a 1 4 + ( 2 s b 1 ) 4 = c 1 4 , is not solvable in ℕ , (where a 1 , b 1 , c 1 ∈2ℕ+1 , pairwise primes, with necessarly 2≤s∈ℕ ). The key idea of our proof is to show that if (F0) holds, then there exist α 2 , β 2 , γ 2 ∈2ℕ+1 , such that ( F 1 ): α 2 4 + ( 2 s−1 β 2 ) 4 = γ 2 4 , holds too. From where, one conclude that it is not possible, because if we choose the quantity 2 ≤ s, as minimal in value among all the solutions of ( F 0 ) , then ( α 2 ,2 s−1 β 2 , γ 2 ) is also a solution of Fermat’s type, but with 2≤s−1d. To reach such a result, we suppose first that (F0) is solvable in ( a 1 ,2 s b 1 , c 1 ) , s ≥ 2 like above;afterwards, proceeding with “Pythagorician divisors”, we creat the notions of “Fermat’s b-absolute divisors”: ( d b , d ′ b ) which it uses hereafter. Then to conclude our proof, we establish the following main theorem: there is an equivalence between (i) and (ii): (i) (F0): a 1 4 + ( 2 s b 1 ) 4 = c 1 4 , is solvable in ℕ , with 2≤s∈ℕ , ( a 1 , b 1 , c 1 )∈ ( 2ℕ+1 ) 3 , coprime in pairs. (ii) ∃( a 1 , b 1 , c 1 )∈ ( 2ℕ+1 ) 3 , coprime in pairs, for wich: ∃( b ′ 2 , b 2 , b ″ 2 )∈ ( 2ℕ+1 ) 3 coprime in pairs, and 2≤s∈ℕ , checking b 1 = b ′ 2 b 2 b ″ 2 , and such that for notations: S=s−λ( s−1 ) , with λ∈{ 0,1 } defined by c 1 − a 1 2 ≡λ( mod2 ) , d b =gcd( 2 s b 1 , c 1 − a 1 )= 2 S b 2 and d ′ b = 2 s−S b ′ 2 = 2 s B 2 d b , where ( 2 s B 2 ) 2 =gcd( b 1 2 , c 1 2 − a 1 2 ) , the following system is checked: { c 1 − a 1 = d b 4 2 2+λ = 2 2−λ ( 2 S−1 b 2 ) 4 c 1 + a 1 = 2 1+λ d ′ b 4 = 2 1+λ ( 2 s−S b ′ 2 ) 4 c 1 2 + a 1 2 =2 b ″ 2 4;and this system implies: ( b 1−λ,2 4 ) 2 + ( 2 4s−3 b λ,2 4 ) 2 = ( b ″ 2 2 ) 2;where: ( b 1−λ,2 , b λ,2 , b ″ 2 )={ ( b ′ 2 , b 2 , b ″ 2 ) if λ=

关键词： Factorisation in ℤ Greatest Common divisor Pythagoras Equation Pythagorician Triplets Fermat's Equations Pythagorician divisors Fermat's divisors diophantine Equations of degree 2 4-Integral Closure of ℤ in ℚ

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Mapping and Floristic diversity of the Nakpadjouak Community Forest, Tami Canton, Togo (West Africa)

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Natural Resources 2024年第4期15卷 83-105页

作者： Senyo Kossi Ehlui Christian Anthony-Krueger Edinam Kola Wouyo Atakpama Alagie Bah Henrik von Wehrden Tchaa Boukpessi West Africa Science Service Center on Climate Change and Adapted Land Use WASCAL University of the Gambia Banjul Gambia laboratoire de Recherche sur la dynamique des Milieux et des Socié t&#233s Department of Geography University of Lom&#233 Lome Togo department of Science Education University of Cape Coast Cape Coast Ghana laboratoire de Botanique et É cologie V&#233g&#233tale D&#233partement botanique Facult&#233 des sciences Universit&#233 de Lom&#233 Lome Togo West Africa Plant Red List Authority (WAPRLA) IUCN Species Survival Commission Gland Switzerland Center for International Forestry Research and World Agroforestry (CIFOR-ICRAF) Nairobi Kenya Faculty of Sustainability Center of Methods Leuphana University of L&#252neburg L&#252neburg Germany laboratoire de Recherches Biogé ographiques et d&#8217Etudes Environnementales Department of Geography University of Lome Lome Togo

Since 2015, community forests have been promoted in Togo as an alternative to protect areas from degradation and as a means of contributing to forest landscape restoration. The study focuses on the Nakpadjouak Community Forest (NCF) in Tami (Togo, West Africa) which contributes to community forests sustainable management. It aims in (i) mapping forest ecosystems and analysing their dynamic and (ii) characterizing the floristic diversity of the NCF. The ecosystems were mapped and their dynamic was evaluated based on Google Earth images of 2014 and 2020. Floristic and forestry inventories were carried out using the transect technique in a sample of 20 plots of 50 m × 20 m. The NCF was made up mainly by wooded/shrub savannahs (95.37%) and croplands/fallow (4.63%) in 2014. These two land use types undergone changes over the 6 years prior to 2020. By 2020, the NCF had 3 land use types: wooded/shrub savannahs (77.59%), open forest/wooded savannahs (22.23%), and croplands/fallows (0.18%). A total of 89 plant species belonging to 70 genera and 28 families were recorded within the NCF. The dominant species are: Heteropogon contortus (L.) ***. and Combretum collinum Fresen. followed by Pteleopsissuberosa Engl. & diels, Annona senegalensis Pers. The most common species are: Lannea acida ***. s.l., A. senegalensis, Vitellaria paradoxa *** subsp. paradoxa, C. collinum and Acacia dudgeonii Craib ex Holland. due to its small area of just 40 hectares and its diverse plant life, this community forest of Savannahs Region is a significant biodiversity hotspot and warrants conservation efforts.

关键词： Community Forest Floristic diversity Land Use Change Biodiversity Hotspot Tami Savannah Region Togo

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Numerical Study of Greenhouse Nocturnal Heat Losses

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Journal of Thermal Science 2011年第4期20卷 377-384页

作者： F.Berroug E.K.Lakhal M.El Omari M.Faraji H.El Qarnia laboratoire d'Automatique de l'Environnement et Procédés de Transfert UniversitéCadi AyyadFacultédes Sciences Semlalia-Département de PhysiqueMarrakech-MarocAffiliéau CNRSTURAC 28 laboratoire de Physique des Materiaux MicroelectroniqueAutomatique et TechniqueDepartement de PhysiquesFaculte des Sciences Ain ChockUniversite Hassan IICasablanca-Maroc

In this study we quantify and analyze different components of nocturnal losses from a heated greenhouse with the presence of vegetation for typical winter weather conditions in Marrakesh-Morocco,using a non linear model,based on the greenhouse heat and mass *** was found that 12% of the total input heat was dissipate as a sensible and latent leakage losses,66% was lost by convective exchange through air-inner *** gain of energy at the inner-cover is dissipated at the outer-cover by radiation(66%)and convection(34%).This results point toward some practical measures to reduce heat losses:increasing air tightness,using covering materials with low-emissivity in the long wave band or putting up an external thermal curtain should provide significant energy savings.

关键词：热损失数值研究温室热量损失非线性模型天气条件组成部分质量平衡

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一种新型多用途污染控制船的研发及其球鼻艏的优化

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哈尔滨工程大学学报（英文版） 2023年第3期22卷 513-526页

作者： Abdelkader Lahlali Zakaria El Maskaoui Lahbib Bousshine Abderrahim dinane laboratoire de Mécanique d’Ingénierie et d’Innovation LM2I ENSEMUniversitéHassan IICasablanca 20103Morocco département Energie Ecole Royale NavaleCasablanca 20052Morocco

Controlling marine pollution caused by hydrocarbons spilling from oil tanker accidents and oil rigs is urgently *** pollution control vessels currently in service worldwide do not meet certain safety criteria,storage capacities,and response times owing to their technical *** study proposes a new concept of multimission and autonomous antipollution vessels capable of acting quickly and efficiently to counter such pollution *** objective of this study is to carry out a total and rapid recovery of the spilled oil slick in complete ***,optimizing the bulbous bow adapted to the pollution control vessel during its displacement is necessary to horizontally straighten the accompanying waves formed around the hull and to laminate the flow upstream of the side openings for the recovery of spilled *** optimization improves the nautical qualities specific to this ship to reduce the total resistance to progress and to standardize the flow upstream of the side openings to allow the collection of spilled oil at high *** optimization study can open a field of application for the construction of modern multi-mission pollution control *** in hull basins will be planned to validate and adjust the results obtained from the simulations.

关键词： Pollution control vessel Multimission ship Oil slick Hydrocarbon Barrage Bow bulb Accompanying waves Resistance to advancement

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Experimental study of the effects of a transversal air-flow deflector in electronics air-cooling

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Journal of Thermal Science 2011年第1期20卷 76-81页

作者： M.REBAY A.ARFAOUI J.PAdeT R.BEN MAAd Université de Reims GRESPI/lab.de ThermomécaniqueFaculté des sciencesBP 103951687 ReimsFrance laboratoire d'Energétique et Transferts Thermique et Massique Faculté des sciences2092 Manar IITunisia

This paper presents an experimental investigation of the influence of a transversal flow deflector on the cooling of a heated block mounted on a flat *** deflector is inclined and therefore it guides the air flow to the upper surface of the *** configuration is simulating the air-cooling of a rectangular integrated circuit or a current converter mounted on an electronic *** electronic component is assumed dissipating low heat power,as such,air forced convection is still a sufficient cooling way even without fan or heat sink on the *** measurements are given by hot and cold wires anemometers and by an InfraRed *** results give details of the effects of the deflection on the hydrodynamic and the thermal fields on and over the block for different inclination *** show that the deviation caused by the deflector may significantly enhance the heat transfer from the *** is also able to avoid local overheating of the electronic *** heat transfer rate and homogenised temperature are shown to be obtained with an inclination angle =30°.

关键词：空气冷却横向气流导流板电子卡实验电子元件电流转换器红外摄像机

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Electrical properties of ^(70)Ge:Ga near the metal–insulator transition

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Journal of Semiconductors 2015年第6期36卷 1-5页

作者： M Errai A El kaaouachi H El idrissi laboratoire MSTI Ecole Supérieure de tecchnologie d'Agadir B.P: 33/S University Ibn ZohrFaculty of Sciences AgadirMorocco laboratoire Electronique électrotechnique Automatique et Traitement de l'Information Département Génie Electrique Faculté des Sciences et Techniques de Mohammedia Université Hassan II Mohammedia CasablancaBP 146 Quartier YasminaMohammedia

The results of the metal-insulator transition （MIT） induced by impurity concentration are presented in the case of metallic and insulating samples 70Ge：Ga p-type. The eight samples studied have Ga concentrations N ranging from 1.848 × 1017 to 1.912 × 10^17 cm-3. The conductivity measurements were carried out at low temperature in the range 1 to 0.019 K. We provide physical explanations to explain the behaviors of the temperature dependence of the electrical conductivity in both sides of the MIT. The data are for a 70Ge：Ga sample prepared and reported by Itoh et aL in Ref. [Itoh K M, Watanabe M, Ootuka Y, et al. J Phys Soc Jpn, 2004, 73（1）： 173].

关键词： 70Ge: Ga semiconductor low temperature impurity concentration metal-insulator variable rangehopping conductivity transport properties

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On-chip generation of hybrid polarization-frequency entangled biphoton states

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Photonics Research 2023年第2期11卷 270-278页

作者： S.FRANCESCONI A.RAYMONd R.dUHAMEL P.FILLOUX A.LEMAITRE P.MILMAN M.I.AMANTI F.BABOUX S.dUCCI Université Paris Cité CNRSLaboratoire Matériaux et Phénomènes Quantiques75013 ParisFrance Université Paris-Saclay CNRSCentre de Nanosciences et de Nanotechnologies91120 PalaiseauFrance

We demonstrate a chip-integrated semiconductor source that combines polarization and frequency entanglement,allowing the generation of entangled biphoton states in a hybrid degree of freedom without *** Al Ga As device is based on type-Ⅱ spontaneous parametric downconversion in a counterpropagating phasematching scheme in which the modal birefringence lifts the degeneracy between the two possible nonlinear interactions. This allows the direct generation of polarization–frequency entangled photons at room temperature and telecom wavelength, and in two distinct spatial modes, offering enhanced flexibility for quantum information protocols. The state entanglement is quantified by a combined measurement of the joint spectrum and Hong–Ou–Mandel interference(raw visibility 70.1% ± 1.1%) of the biphotons, allowing to reconstruct a restricted density matrix in the hybrid polarization–frequency space.

关键词： space. matching restricted

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First-principles prediction of the magnetism of 4f rare-earth-metal-doped wurtzite zinc oxide

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Journal of Rare Earths 2014年第8期32卷 715-721页

作者： A.G.El Hachimi H.Zaari A.Benyoussef M.El Yadari A.El Kenz laboratoire de Magnétisme et Physique des Hautes Energies LMPHE (URAC 12) Département de Physique B.P.1014 Faculté des SciencesUniversité Mohammed V-Agdal Institut of Nanomaterials and Nanotechnology Hassan II Academy of Science and Technology department of Science Moulay Ismail University Faculté Polydisciplinaire

Electronic structure and magnetic properties of wurtzite ZnO semiconductor doped with rare earth （RE=La, Ce, Pr, Pm, Nd, Sm, Eu, Gd, Tb, dy, Ho, Er, Tm and Yb） atoms were studied using spin-polarized density functional theory based on the full-potential linear augmented plane wave （FP-LAPW） method as implemented in the Wien2k code. In this approach the generalized gradient approximation （GGA） was used for the exchange-correlation （XC） potential. Our results showed that the substitution of RE ions in ZnO induced spins polarized localized states in the band gap. Moreover, the studied dMSs compounds retained half metallicity at dopant concentration x=0.625%for most of the studied elements, with 100%spin polarization at the Fermi level （EF）. The total magnetic moments of these compounds existed due to RE 4f states present at EF, while small induced magnetic moments existed on other non-magnetic atoms as well. Finally, the energy difference between far and near configurations was investigated. It was found that the room temperature ferromagnetism was possible for RE-doped ZnO at near configuration. Since the RE-RE separation was long enough （far configuration） for magnetic coupling, the system became paramagnetic or antiferromagnetic ground state.

关键词： ZnO rare earths ferromagnetism dMS electronic structure magnetic properties half-metallic RE-doped ZnO FP-LAPW method density functional theory

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