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Open Journal of Ecology 2024年第1期14卷 54-65页

作者： Amos Baninwain Nambima Thierry Dèhouégnon Houehanou Narcisse Yehouenou Dowo Michée Adjacou Abdul Sodick Alassiri Gérard Gouwakinnou laboratory of Ecology Botany and Plant Biology (LEB) Faculty of Agronomy (FA) University of Parakou (UP) Parakou Republic of Benin

Throughout the world, climate change is threatening the human population. In West Africa, smallholder farmers in indigenous agricultural societies typically hold considerable knowledge. Therefore, this study was conducted in West Atacora of Benin Republic to assess the drivers of farmers’ perceptions of climate change risk. We used a random sampling technique to select 360 households’ heads who were interviewed regarding different climate change risks perception. Binomial logistic regression was used to assess the drivers of farmers’ perceptions of climate change risks. The results showed that the farmers in drier areas had a higher perception of the global risk of climate change than those in humid areas. The same trend was observed for the seven different individual’s climate change risk investigated. The study identified also membership of farm organizations as main sociodemographic characteristic that explains farmers’ perception of climate change risk perception. These findings are helpful tools to sensitize the local people on climate change risk and cope with the risk in agricultural lands.

关键词： Climate Change Risk Local Ecological Knowledge Socio-Demographic Characteristics Benin West Africa

Assessing Morphological Traits Variation and Fruit Production of <i>Lophira lanceolata</i>(Ochnaceae) in Benin

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American Journal of Plant Sciences 2019年第6期10卷 1048-1060页

作者： Aliou Dicko Armand Kuyéma Natta Honoré Samadori S. Biaou Arcadius Akossou laboratory of Ecology Botany and Plant Biology (LEB) Parakou Benin Faculty of Agronomy University of Parakou (UP) Parakou Benin

Lophira lanceolata is an oleaginous tree species whose fruit is used for vegetable oil production in Benin. The present study highlighted the fruit production and characterization of the morphological traits of the fruits and seeds of this species. A total of 196 mature trees in production were randomly sampled in Borgou-Nord, Borgou-Sud and Atacora Chain phytodistricts. Descriptors were characterized globally at the level of phytodistricts surveyed. Pearson correlation test stands out the relationships between the different descriptors. The effect of phytodistricts on fruit production was analyzed using a Generalized Linear Model (GLM) and the variation of morphological traits between phytodistricts was examined through Kruskal-Wallis test. Finally, SMA regression was used to test the influence of the phytodistrict on the relationship between L. lanceolata seed and fruit weight. This study revealed that there is a positive and significant correlation between the morphological traits of fruits and those of seeds. Trees descriptors (e.g. total height, diameter at breast height, and leaf petiole length) predict fruit production of L. lanceolata, but are not significantly correlated with fruit and seed traits. In the Atacora Chain phytodistrict, breeding trees are entering production with small diameter, low height and produce little number of fruits per tree with higher weight, unlike the Borgou-Nord and Borgou-Sud phytodistricts. These results can be useful in the selection of early breeding tree in Atacora Chain phytodistrict and high-yielding trees from individuals in the Borgou-Nord and Borgou-Sud phytodistricts.

关键词： False Shea Phenotypic Traits Fruit Production Phytodistricts Conservation

Super twisting sliding mode approach applied to voltage orientated control of a stand-alone induction generator

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Protection and Control of Modern Power Systems 2021年第1期6卷 233-241页

作者： Yacine Bendjeddou Abdelhakim Deboucha Larafi Bentouhami Elkheir Merabet Rachid Abdessemed laboratory of electrical and materials engineering(LGEM) Higher School of Electrical and Energetic Engineering of Oran31000Bir El DjirAlgeria Ecole Supérieure des Sciences Appliquées d’Alger Electrical Engineering Department16000AlgiersAlgeria Department of electromechanical University of Bordj Bou Arréridj34000El AnceurAlgeria laboratory leb Department of Electrical EngineeringUniversity of Batna-205000FesdisAlgeria

To enhance the robustness and dynamic performance of a self-excited induction generator (SEIG) used in a stand-alone wind energy system (WES), a virtual flux oriented control (VFOC) based on nonlinear super-twisting sliding mode control (STSMC) is adopted. STSMC is used to replace the conventional proportional-integral-Fuzzy Logic Controller (PI-FLC) of the inner current control loops. The combination of the proposed control strategy with space vector modulation (SVM) applied to a PWM rectifier brings many advantages such as reduction in harmonics, and precise and rapid tracking of the references. The performance of the proposed control technique (STSMC-VFOC-SVM) is verified through simulations and compared with the traditional technique (PI-FLC-VFOC-SVM). It shows that the proposed method improves the dynamics of the system with reduced current harmonics. In addition, the use of a virtual flux estimator instead of a phase-locked loop (PLL) eliminates the line voltage sensors and thus increases the reliability of the system.

关键词： Self-excited induction generator Virtual flux oriented control Back-to-back converter Super twisting sliding mode control PI-fuzzy controller wind energy

Ecophysiology of Lophira lanceolata Seeds Germination and Conservation Perspectives

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American Journal of Plant Sciences 2022年第9期13卷 1167-1182页

作者： Aliou Dicko Belarmain Fandohan Armand Kuyema Natta laboratory of Ecology Botany and Plant Biology (LEB) Parakou Benin Ecole de Foresterie Tropicale Université Nationale d’Agriculture (UNA) Ketou Benin Faculty of Agronomy University of Parakou (UP) Parakou Benin

Lophira lanceolata is a multi-purpose woody plant species used by local populations in Benin. Its seeds are used for the manufacture of edible vegetable oil and also for medicinal care. However, reproduction by seed of this plant species is compromised not only by the multiple uses made of the seeds, but also by the difficulties of germination in the natural environment. Several ecological factors could explain this difficulty of germination. In this study, we investigated the species seeds ecophysiology in order to develop seedlings production techniques for its reintroduction. Beta regression was performed to test the effect of water, light and provenance on seeds germination rate. The germination speed was expressed as the median germination time. The results showed that the germination rate was better under light conditions (β = 0.77674 ± 0.14954, Z = 5.194, p < 0.0000). The germination rate decreased as the frequency of watering increased (β = -0.28222 ± 0.14809, Z = -1.906, p = 0.0567). The best provenance was the phytodistrict of Atacora chain. The cumulative germination rate reached 50% after 54 days for seeds collected from Atacora chain and after 57 days under light conditions. Regarding the level of watering, the germination rate remained below 50% regardless the treatment. The germination speed was higher for seeds collected from Atacora chain and that have germinated under light conditions and watered twice a week. For the sustainable management of L. lanceolata, domestication by establishment of plantations by rural communities is recommended based on seeds from Atacora chain.

关键词： Benin Germination Speed Oilseed Phytodistrict Recalcitrant Seed West Africa

Histo-blood group antigens in Crassostrea gigas and binding profiles with GⅡ.4 Norovirus

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Journal of Oceanology and Limnology 2018年第4期36卷 1383-1391页

作者： MA Liping LIU Hui SU Laij in ZHAO Feng ZHOU Deqing DUAN Delin Key laboratory of Experimental Marine Biology Institute of OceanologyChinese Academy of SciencesQingdao 266071China Key laboratory for Sustainable Utilization of Marine Fisheries Resources Ministry of AgricultureYellow Sea Fisheries Research InstituteChinese Academy of Fishery SciencesQingdao 266071China laboratory for Marine Biology and Biotechnology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China

Noroviruses(NoVs) are the main cause of viral gastroenteritis outbreaks worldwide, and oysters are the most common carriers of NoV contamination and transmission. NoVs bind specifically to oyster tissues through histo-blood group antigens(HBGAs), and this facilitates virus accumulation and increases virus persistence in oysters. To investigate the interaction of HBGAs in Pacific oysters with GⅡ.4 NoV, we examined HBGAs with ELISAs and investigated binding patterns with oligosaccharide-binding assays using P particles as a model of five GⅡ.4 NoV capsids. The HBGAs in the gut and gills exhibited polymorphisms. In the gut, type A was detected(100%), whereas type leb(91.67%) and type A(61.11%) were both observed in the gills. Moreover, we found that seasonal NoV gastroenteritis outbreaks were not significantly associated with the specific HBGAs detected in the oyster gut and gills. In the gut, we found that strain-2006 b and strain-96/96 US bound to type A and H1 but only weakly bound to type leb; in contrast, the Camberwell and Hunter strains exhibited weak binding to types H1 and Ley, and strain-Sakai exhibited no binding to any HBGA type. In the gills, strain-96/96 US and strain-2006 b bound to type leb but only weakly bound to type H1; strains Camberwell, Hunter, and Sakai did not bind to oyster HBGAs. Assays for oligosaccharide binding to GⅡ.4 NoV P particles showed that strain-95/96 US and strain-2006 b strongly bound to type A, B, H1, leb, and Ley oligosaccharides, while strains Camberwell and Hunter showed weak binding ability to type H1 and Ley oligosaccharides and strain-Sakai showed weak binding ability to type leb and Ley oligosaccharides. Our study presents new information and enhances understanding about the mechanism for NoV accumulation in oysters. Further studies of multiple NoV-tissue interactions might assist in identifying new or improved strategies for minimizing contamination, including HBGA-based attachment inhibition or depuration.

关键词： Crassostrea gigas norovirus histo-blood group antigen binding

The Low Energy X-ray telescope (LE) onboard the Insight-HXMT astronomy satellite

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Science China(Physics,Mechanics & Astronomy) 2020年第4期63卷 49-61页

作者： Yong Chen WeiWei Cui Wei Li Juan Wang YuPeng Xu FangJun Lul YuSa Wang TianXiang Chen DaWei Han Wei Hu Yi Zhang Jia Huo YanJi Yang MaoShun Li Bo Lu ZiLiang Zhang TiPei Li ShuangNan Zhang ShaoLin Xiong Shu Zhang RongFeng Xue XiaoFan Zhao Yue Zhu YuXuan Zhu HongWei Liu YiJung Yang Fan Zhang Key laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China Department of Physics Tsinghua UniversityBeijing 100084China Department of Education Lu Liang UniversityLuliang 033000China Qian Xuesen laboratory of Space Technology China Academy of Space TechnologyBeijing 100094China College of Physics Jilin UniversityChangchun 130023China

The Low Energy X-ray telescope(LE) is one of the three main instruments of the Insight-Hard X-ray Modulation Telescope(Insight-HXMT). It is equipped with Swept Charge Device(SCD) sensor arrays with a total geometrical area of 384 cm^2 and an energy band from 0.7 to 13 ke V. In order to evaluate the particle induced X-ray background and the cosmic X-ray background simultaneously, LE adopts collimators to define four types of Field Of Views(FOVs), i.e., 1.6°×6°, 4°×6°, 50°-60°×2°-6 oand the blocked ones which block the X-ray by an aluminum cover. LE is constituted of three detector boxes(LEDs) and an electric control box(leb) and achieves a good energy resolution of 140 e V@5.9 ke V, an excellent time resolution of 0.98 ms, as well as an extremely low pileup(<1%@18000 cts/s). Detailed performance tests and calibration on the ground have been performed,including energy-channel relation, energy response, detection efficiency and time response.

关键词： LE X-ray telescope SCD collimators

Achieving white-light emission in a single-component polymer with halogen-assisted interaction

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Science China Chemistry 2021年第3期64卷 467-477页

作者： Zhuxin Zhou Zhu Mao Zhan Yang Tingting Yang Longji Zhu Yubo Long Zhenguo Chi Siwei Liu Matthew P.Aldred Xudong Chen Jiarui Xu Yi Zhang Key laboratory for Polymeric Composite&Functional Materials of Ministry of Education Key L aboratory for High-Performance Polymer Composites of Guangdong ProvinceGuangdong Engineering Technology Research Centre for High-performance Organic and Polymer Photoelectric Functional FilmsState Key Laboratory of Optoelectronic Materials and TechnologiesSchool of ChemistrySun Yat-sen UniversityGuangzhou 510275China Lomox Limited Bank HouseMarket SquareCongletonCheshire CW121ETUnited Kingdom Shenzhen Yanyi New Materials Co. Ltd.Shenzhen 518110China

White-light emitting(WLE) polymers have attracted continuous attention for their promising applications in solid-state lighting,flexible display and related fields. However, achieving dual-emission and pure white-light emission in a single-component polymer is still challenging. In this study, a brominated single-component polymer Br OD-TFB was designed and synthesized,which shows dual-emission and white light emission properties in solution and room-temperature phosphorescence(RTP) in thin films. The dual-emission properties can be tuned by concentration, solvent polarity, and excitation energy. Spectral analyses and theoretical calculations reveal that the origin of the high-energy emission band(HEB) is intramolecular charge transfer(ICT)along the polymer chain, whilst the low-energy emission band(leb) originates from the excited-state related to the intra-chain and inter-chain C–Br···π interactions as demonstrated by the single-crystal structure of the model compound. Appropriate control of the formation and the destruction of the halogen-assisted interactions can initiate white-light emission in the singlecomponent polymer. More interestingly, by dispersing Br OD-TFB(0.1 wt%) in a non-emissive, colorless and transparent polymer, the characteristics of this white-light emission can be fully demonstrated while exhibiting unexpected RTP properties,with photoluminescence quantum efficiency(Φ_(PL)) of up to 23% and CIE coordinates of(0.32, 0.32).

关键词： white-light emission single-component polymer halogen-assisted interaction functional polyimide mechanism

Synthesis,photoluminescence properties and thermal investigation by TG-MS of RE（DAS）3·xH2O(RE=Eu3+,Tb3+)

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Journal of Rare Earths 2019年第11期37卷 1164-1169页

作者： Rodrigo V.Rodrigues Lukasz Marciniak Latif U.Khan Antonio A.L.Marins Robert Tomala Emanuel J.B.Muri Jivaldo R.Matos Wieslaw Strek Institute of Chemistry University of Sao PauloButanta 74826077 Sao PauloBrazil Institute of Low Temperature and Structure Research Polish Academy of SciencesOkolna 250-422 WroclawPoland Brazilian Nanotechnology National laboratory(LNNano-CNPEM) Campinas 13083-100Sao PauloBrazil Department of Chemistry Federal University of Espirito SantoVitoria 29220-000Brazil

Rare earth(Ⅲ)diphenyl-4-amine sulfonates(RE(DAS)3·xH2O,RE=Eu^3+,Tb^3+)phosphors were synthesized by precursor method from barium diphenyl-4-amine sulfonate and rare earth ***,TG/DSC coupled to mass spectrometry(TG/DSC/MS),X-ray powder diffraction(XPD),scanning electron microscopy(SEM)and photo luminesce nce(PL)spectroscopy were utilized to structurally and morphologically characterize the *** decomposition of Eu(DAS)3·7H2O and Tb(DAS)3·2H2O at 973 K under dynamic air atmosphere results in crystalline Eu2O2SO4 and Tb2O2SO4 materials,***,MS spectra reveal the liberation of thermal decomposition products of precursors,largely as CO2,NO2 and SO2 *** diphenyl-4-amine sulfonate(DAS)ligand demonstrats a good stabilizing property for Eu^3+and Tb^3+*** Eu(DAS)3·7H2O and Tb(DAS)3·2H2O compounds display efficient red and green emissions,under UV excitation,arising from the 5D0→7FJ(J=0-4)and 5D4→7FJ(J=0-6)transitions of the Eu^3+and Tb^3+ions,respectively.

关键词： Optical properties Rare earth oxysulfate Thermal decomposition Eu(DAS)3·7H2O Tb(DAS)3·2H2O Rare earths

Lewis blood genotypes of peptic ulcer and gastric cancer patients in Taiwan

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World Journal of Gastroenterology 2005年第31期11卷 4891-4894页

作者： Chi-Jung Yei Jan-Gowth Chang Mu-Chin Shih Sheng-Fung Lin Chao-Sung Chang Fu-Tsong Ko Kuang-Yang Lin Ta-Chih Liu Blood Bandk Kaohsiung Medical University HospitalKaohsiung Taiwan China Depamnent of laboratory Medicine China Medical University and Hospital Taichung Taiwan China Division of Hematology/Oncology Department of Internal Medicine Kaohsiung Medical University Hospital Kaohsiung Taiwan China Department of Internal Medicine Taipei Municipal Jen-Ai Hospital Taipei Taiwan China

AIM： The Lewis b （Le^b） antigen has been implicated as a possible binding site for attachment of Helicobacter pylori （H pylon） to gastric mucosa. However, studies both supporting and denying this association have been reported in the literature. Differences in secretor （Se） genotype have been suggested as a possible reason for previous discrepancies. Therefore, we investigated the relationship between Le and Se genotypes and Hpylori infection rates in people with peptic ulcer or gastric cancer. METHODS： Peripheral blood samples were obtained from 347 patients with endoscopic evidence of peptic ulcer disease （235 cases of duodenal ulcer, 62 of gastric ulcer, and 50 of combined duodenal ulcer/gastric ulcer） and 51 patients with gastric cancer on endoscopy. Peripheral blood specimens from 101 unrelated normal volunteers were used as controls. Lewis phenotype was determined using an antibody method, whereas Le and Se genotypes were determined by DNA amplification and restriction enzyme analysis. Gastric or duodenal biopsies taken from patients with endoscopic evidence of peptic ulcer or gastric cancer were cultured for Hpylotri Isolates were identified as Hpylori by morphology and production of urease and catalase. The Hpyloriinfection status was also evaluated by rapid urease test （CLO test）, and urea breath test （13^C-UBT）. Results of studies were analyzed by chi-square test （taken as significant）. RESULTS： Hpyloriwas isolated from 83.7% （303/347） of patients with peptic ulcer disease. Statistical analysis did not show any significant difference in Lewis phenotype or genotype between patients with and without Hpylori infection. No significant association was found between Lewis genotype and peptic ulcer or gastric ***： Lewis blood genotype or phenotype may not play a role in the pathogenesis of Hpyloriinfection. However, bacterial strain differences and the presence of more than one attachment mechanism may limit the value of epidemiological studies in e

关键词： Lewis histoblood group Helicobacter pylorr Peptic ulcer Gastric cancer

日籍巴西人群中幽门螺杆菌血清阳性与Lewis和Secretor基因多态性的联系

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世界核心医学期刊文摘（胃肠病学分册） 2005年第3期1卷 50-51页

作者： Oba-hinjo S.M. Uno M. Ito L.S. 王志宇 laboratory of Molecular Biology Department of Neurology University of So Paulo Av. Dr. Arnaldo 455 01246-903 So Paulo SP Brazil

Background. Secretor (Se) and Lewis (Le) genes are involved in the synthesis of Lewis b (leb) and type I antigens throughout the body, especially in the epithelial cells of gastric mucosa. Helicobacter pylori can attach to the gastric epithelial cells with the blood group antigen binding adhesin, which binds to leb or H type I carbohydrate structures. In a previous study, a marked association between H. pylori seropositivity and polymorphism of the Se and Le genes was observed among Japanese outpatients of a gastroenterology clinic. The present work aims to investigate the associations between Se and Le gene polymorphisms and H. pylori infection among Japanese Brazilians. Methods. The subjects consisted of 942 healthy volunteer Japanese Brazilians, who were tested for the presence of anti H. pylori IgG antibodies and genotyped for Se and Le polymorphisms. Results. The sex age adjusted odds ratios (aORs) for H. pylori seropositivity were 0.99 for the Sese genotype relative to the SeSe genotype (95%confidence interval , 0.73-1.33), and 1.03 for sese relative to SeSe (95%CI, 0.71-1.48). On the other hand, the aOR for the subjects with the le allele (Lele or lele) relative to the LeLe genotype was 1.48 (95%CI, 1.07-1.79). When the Se and Le genotypes were analyzed in combination according to risk group, no statistically significant association was observed. Conclusions. These results are inconsistent with previous work and may have been modulated by an external factor or some other unidentified factor. Japanese Brazilians are geno typically the same as Japanese, but their lifestyle is adapted to that of Brazil. Further investigations are necessary to clarify this influence on susceptibility to H. pylori infection.

关键词： Lewis Secretor 基因多态性血清阳性胃上皮细胞血型抗原胃黏膜上皮巴西人黏附素胃肠病