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Chinese Journal of Oceanology and Limnology 2011年第2期29卷 246-251页

作者：周克潘红苗张圣妲岳海东肖天吴龙飞 Yantai Institute of Coastal Zone Research Chinese Academy of Sciences Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of Sciences Graduate University of Chinese Academy of Sciences College of Marine Life Science Ocean University of China France-China bio-Mineralization and Nano-Structures Laboratory laboratoire de Chimie Bacterienne Université de la Méditerranée Aix-Marseille IICNRSMarseilleFrance

Multicellular magnetotactic prokaryotes （MMPs） are a group of aggregates composed of 7-45 gram-negative cells synthesizing intracellular magnetic crystals. Although they are thought to be globally distributed, MMPs have been observed only in marine environments in America and Europe. Most MMPs share a rosette-like morphology and biomineralize iron sulfide crystals. In the present study, abundant MMPs were observed, with a density of 26 ind./cm^3, in the sediments of a coastal lagoon, Lake Yuehu, in the Yellow Sea. Optical microscopy showed that all of them were rosette shaped with a diameter of 5.5±0.8 μm. Transmission electron microscopy revealed that these MMPs were composed of 10- 16 ovoid cells and flagellated peritrichously. High-resolution transmission electron microscopy and energy dispersive X-ray analysis indicated that they biomineralized bullet-shaped magnetite crystals in highly organized parallel chains within which the magnetosomes were oriented in the same direction. This is the first report of MMPs from Asia and demonstrates the ubiquitous distribution of MMPs.

关键词： multicellular magnetotactic prokaryotes rosette-like magnetosomes magnetite Yellow Sea

Origin of superconductivity in hole doped Srbio_(3) bismuth oxide perovskite from parameter-free first-principles simulations

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npj Computational Materials 2023年第1期9卷 2044-2052页

作者： Julien Varignon laboratoire CRISMAT CNRS UMR 6508ENSICAENNormandie Université6 boulevard Maréchal JuinF-14050Caen Cedex 4France

The recent discovery of nickel oxide superconductors have highlighted the importance of first-principles simulations forunderstanding the formation of the bound electrons at the core of superconductivity. Nevertheless, superconductivity in oxides isoften ascribed to strong electronic correlation effects that density functional theory (DFT) cannot properly take into account,thereby disqualifying this technique. Being isostructural to nickel oxides, Sr_(1-x)K_(x)bio_(3) superconductors form an ideal testbed forunveiling the lowest theory level needed to model complex superconductors and the underlying pairing mechanism yieldingsuperconductivity. Here I show that parameter-free DFT simulations capture all the experimental features and related quantities of Sr_(1-x)K_(x)bio_(3) superconductors, encompassing the prediction of an insulating to metal phase transition upon increasing the K dopingcontent and of an electron-phonon coupling constant of 1.22 in sharp agreement with the experimental value of 1.3 ± 0.2. Theproximity of a disproportionated phase is further demonstrated to be a prerequisite for superconductivity in bismuthates.

关键词： superconductivity bismuth parameter

Is non-host pollen suitable for generalist bumblebees？

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Insect Science 2018年第2期25卷 259-272页

作者： Maryse Vanderplanck Sylvain Decleves Nathalie Roger Corentin Decroo Guillaume Caulier Gaetan Glauser Pascal Gerbaux Georges Lognay Aurore Richel Nathalie Escaravage Denis Michez Laboratory of Zoology Research Institute for Biosciences University of Mons--UMONS Mons Organic Synthesis and Mass Spectrom- etry Laboratory Interdisciplinary Center for Mass Spectrometry University of Mons--UMONS Mons Research Institute for biosciences Biology of Marine Organisms and Biomimetics University of Mons--UMONS Mons Belgium Neuch＆tel Platform of Analytical Chem- istry University of Neuch＆tel Neuchtel Switzerland Laboratory of Analytical Chemistry University of Liege Gembloux Agro-Bio Tech Gembloux Unit of biological and Industrial Chemistry （CBI） University of Liege Gembloux Agro-Bio Tech Gembloux Belgium laboratoire Evolution et Diversity biologique （EDB） CNRS ENFA UMR 5174 University Toulouse 3 Paul Sabatier Toulouse France

Current evidence suggests that pollen is both chemically and structurally protected. Despite increasing interest in studying bee-flower networks, the constraints for bee development related to pollen nutritional content, toxicity and digestibility as well as their role in the shaping of bee-flower interactions have been poorly studied. In this study we combined bioassays of the generalist bee Bombus terrestris on pollen of Cirsium, Trifolium, Salix, and Cistus genera with an assessment of nutritional content, toxicity, and digestibility of pollen. Microcolonies showed significant differences in their development, non-host pollen of Cirsium being the most unfavorable. This pollen was characterized by the presence of quite rare 37-sterols and a low digestibility. Cirsium consumption seemed increase syrup collection, which is probably related to a detoxification mixing behavior. These results strongly suggest that pollen traits may act as drivers of plant selection by bees and partly explain why Asteraceae pollen is rare in bee generalist diet.

关键词： bee-flower interactions generalist bees pollen defences

Dynamic Model and Motion Mechanism of Magnetotactic Bacteria with Two Lateral Flagellar Bundles

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Journal of bionic Engineering 2012年第2期9卷 200-210页

作者： Cenyu Yang Chuanfang Chen Qiufeng Ma Longfei Wu Tao Song Institute of Electrical Engineering Chinese Academy of Sciences Beijing 100190 P. R. China Graduate University of Chinese Academy of Sciences Beijing 100049 P. R. China France-China bio-Mineralization and Nano-Structures Laboratory Beoing 1 00193 P. R. China laboratoire de Chimie Bacterienne UPR9043 Universite de la Mediterranee lnstitut de Microbiologie de la Mediterranee CNRS F-13402 Marseille Cedex 20 France

Magnetotactic Bacteria （MTB） propel themselves by rotating their flagella and swim along the magnetic field lines. To analyze the motion of MTB, MTB magneto-ovoid strain MO-1 cells, each with two bundles of flagella, were taken as research object. The six-degrees-of-freedom （6-DoF） dynamic model of MO-1 was established based on the Newton-Euler dynamic equations. In particular, the interaction between the flagellum and fluid was considered by the resistive force theory. The simulated motion trajectory of MTB was found to consist of two kinds of helices： small helices restilting from the imbalance of force due to flagellar rotation, and large helices arising from the different directions of the rotation axis of the cell body and the propulsion axis of the flagellum. The motion behaviours of MTB in various magnetic fields were studied, and the simulation results agree well with the experiment results. In addition, the rotation frequency of the flagella was estimated at 1100 Hz, which is consistent with the average rotation rate for Na^＋-driven flagellar motors. The included angle of the magnetosome chain was predicted at 40° that is located within 20° to 60° range of the observed results. The results indicate the correctness of the dynamic model, which may aid research on the operation and control of MTB-propelled micro-actuators. Meanwhile, the motion behaviours of MTB may inspire the development of micro-robots with new driving mechanisms.

关键词： magnetotactic bacteria dynamic model resistive force theory motion mechanism

Quasi-Three-Dimensional Cyclotriphosphazene-Based Covalent Organic Framework Nanosheet for Efficient Oxygen Reduction

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Nano-Micro Letters 2023年第9期15卷 550-561页

作者： Jianhong Chang Cuiyan Li Xiaoxia Wang Daohao Li Jie Zhang Xiaoming Yu Hui Li Xiangdong Yao Valentin Valtchev Shilun Qiu Qianrong Fang State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin UniversityChangchun 130012People’s Republic of China State Key Laboratory of bio-Fibers and Eco-Textiles College of Materials Science and EngineeringQingdao UniversityQingdao 266071People’s Republic of China Qingdao Institute of bioenergy and bioprocess Technology Chinese Academy of Sciences189 Song Ling RdQingdao 266101ShandongPeople’s Republic of China laboratoire Catalyse et Spectrochimie CNRSENSICAENUNICAENNormandie Univ6 Marechal Juin14050 CaenFrance

Metal-free carbon-based materials are considered as promising oxygen reduction reaction(ORR)electrocatalysts for clean energy conversion,and their highly dense and exposed carbon active sites are crucial for efficient *** this work,two unique quasi-three-dimensional cyclotriphosphazene-based covalent organic frameworks(Q3CTP-COFs)and their nanosheets were successfully synthesized and applied as ORR *** abundant electrophilic structure in Q3CTP-COFs induces a high density of carbon active sites,and the unique bilayer stacking of[6+3]imine-linked backbone facilitates the exposure of active carbon sites and accelerates mass diffusion during *** particular,bulk Q3CTP-COFs can be easily exfoliated into thin COF nanosheets(NSs)due to the weak interlayerπ-πinteractions.Q3CTP-COF NSs exhibit highly efficient ORR catalytic activity(half-wave potential of 0.72 V *** in alkaline electrolyte),which is one of the best COF-based ORR electrocatalysts reported so ***,Q3CTP-COF NSs can serve as a promising cathode for Zn-air batteries(delivered power density of 156 mW cm-2 at 300 mA cm^(-2)).This judicious design and accurate synthesis of such COFs with highly dense and exposed active sites and their nanosheets will promote the development of metal-free carbon-based electrocatalysts.

关键词： Covalent organic framework Quasi-three-dimensional structures Oxygen reduction reaction Metal-free electrocatalyst

Erratum to “Theoretical Study of the Reaction of (2, 2)-Dichloro (Ethyl) Arylphosphine with Bis (2, 2)-Dichloro (Ethyl) Arylphosphine by Hydrophosphination Regioselective by the DFT Method” [Computational Chemistry 5 (2017) 113-128]

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Computational Chemistry 2020年第1期8卷 14-16页

作者： Kouadio Valery Bohoussou Anoubilé Benié Mamadou Guy-Richard Koné Affi Baudelaire Kakou Kafoumba Bamba Nahossé Ziao laboratoire de Thermodynamique et de Physico-Chimie du Milieu UFR SFA Universite Nangui Abrogoua Abidjan Republique de Cote-d’Ivoire laboratoire de Chimie bio-Organique et de Substances Naturelles (LCBOSN) UFR SFA Universite Nangui Abrogoua Abidjan Republique de Cote-d’Ivoire

The original online version of this article (Kouadio Valery Bohoussou1, Anoubilé Benié2, Mamadou Guy-Richard Koné1, Affi Baudelaire Kakou2, Kafoumba Bamba1, Nahossé Ziao1) Theoretical Study of the Reaction of (2, 2)-Dichloro (Ethyl) Arylphosphine with Bis (2, 2)-Dichloro (Ethyl) Arylphosphine by Hydrophosphination Regio selective by the DFT Method. Computational Chemistry 5 (2017) 113-128. DOI: 10.4236/cc.2017.53010) unfortunately contains a mistake. The author wishes to correct the errors from Table 3 to Table 4, on pages 121 and the beginning of page 122.

关键词： Erratum

Theoretical Study of the Reaction of (2, 2)-Dichloro (Ethyl) Arylphosphine with Bis (2, 2)-Dichloro (Ethyl) Arylphosphine by Hydrophosphination Regioselective by the DFT Method

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Computational Chemistry 2017年第3期5卷 113-128页

作者： Kouadio Valery Bohoussou Anoubilé Benié Mamadou Guy-Richard Koné Affi Baudelaire Kakou Kafoumba Bamba Nahossé Ziao laboratoire de Thermodynamique et de Physico-Chimie du Milieu UFR SFA Université Nangui Abrogoua Abidjan République de C&ocirc te-d’Ivoire laboratoire de Chimie bio-Organique et de Substances Naturelles (LCBOSN) UFR SFA Université Nangui Abrogoua Abidjan République de C&ocirc te-d’Ivoire

For this work, we have selected two reactions for the formation of (2,2)-dichloro (ethyl) Arylphosphine and bis (2,2)-dichloro(ethyl)arylphosphine compounds by hydrophosphination. Global and local reactivity parameters, thermodynamic parameters of reactions, Transition states, the Fukui function, the local softness, the local electrophility index, and nucleophility index, Natural population analyses (NPA) and Mulliken (MK) were calculated with DFT method at B3LYP/6-311+G(d, p) level. The analysis of potential energy surfaces and the nature of the reaction mechanism have been determined. The various results obtained revealed that the addition of Arylphosphine is regiospecific. The phenylphosphine is more stable than the thiophenylphosphine. The theoretical results are consistent with experience.

关键词： Hydrophosphination Phosphine HOMO LUMO Fukui Index Transition State

Antioxidant capacity and genoprotective effect of ethanol fruit extract from Detarium microcarpum Guill. and Perr.(Caesalpiniaceae)

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Asian Pacific Journal of Tropical biomedicine 2017年第1期7卷 32-36页

作者： AblasséRouamba Maurice Ouedraogo Martin Kiendrebeogo laboratoire de biochimie et Chimie Appliqu′ees(LAbioCA) UFR-SVTUniversit′e de Ouagadougou03 BP 7021Ouagadougou 03Burkina Faso laboratoire de Physiologie Animale(LAPA) UFR-SVTUniversit′e de Ouagadougou09 BP 848Ouagadougou 09Burkina Faso

Objective: To evidence the ability of ethanol fruit extract from Detarium microcarpum(D. microcarpum) to preserve DNA integrity against oxidative genomic ***: Ethanol extract from D. microcarpum fruit pulp was analyzed for its antioxidant capacity using ferric reducing antioxidant power, 2,2-diphenyl-1-picrylhydrazyl,2,20-azinobis-3-ethyl-ethylbenzothiazoline-6-sulphonate, superoxide anion, deoxyribose degradation and lipid peroxidation models. The genoprotective activity was assessed ex vivo by comet assay, on liver cells of NMRI female mice using cyclophosphamide(CP) as genotoxic ***: Ethanol extract from D. microcarpum fruit pulp exhibited interesting antioxidant activity in 2,2-diphenyl-1-picrylhydrazyl, deoxyribose degradation and lipid peroxidation assays. The extract did not present any genotoxic effect but protected DNA against CP-induced damages with a dose-dependent manner. The genoprotective effect observed was related to the antioxidant molecules of the fruit that scavenged the hydroxyl radical(generated by the metabolism of CP) as well as the peroxyl and alkoxyl radicals issued from lipid peroxidation. Other mechanisms such as inactivation of CP metabolism to genotoxic end products, induction of the expression of antioxidant and DNA repair enzymes have been ***: Our results suggest that the wild edible fruit from D. microcarpum could be beneficial on consumer's health by its antioxidant and genoprotective effects, particularly during chemotherapies exhibiting genotoxic effects like CP in cancer treatment.

关键词： Antioxidant activity Comet assay Detarium microcarpum Genoprotection

Soil Contamination due to E-Waste Disposal and Recycling Activities: A Review with Special Focus on China

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Pedosphere 2012年第4期22卷 470-488页

作者： G. ECHEVARRIA T. STERCKEMAN M. O. SIMONNOT J. L. MOREL INPL(ENSAIA)/INRA Laboratoire Sols et Environnement 2 Avenue de la For et de Haye BP 172 54505 Vandoeuvre-lès-Nancy Cedex (France) laboratoire Réactions et Génie des Procédés (LRGP) Université de Lorraine-CNRS (UPR 3349) 1 Rue Grandville BP20451 54001 Nancy Cedex (France)

Considering that even contaminated soils are a potential resource for agricultural production, it is essential to develop a set of cropping systems to allow a safe and sustainable agriculture on contaminated lands while avoiding any transfer of toxic trace elements to the food chain. In this review, three main strategies, i.e., phytoexclusion, phytostabilization, and phytoextraction, are proposed to establish cropping systems for production of edible and non-edible plants, and for extraction of elements for industrial use. For safe production of food crops, the selection of low-accumulating plants/cultivars and the application of soil amendments are of vital importance. Phytostabilization using non-food energy and fiber plants can provide additional renewable energy sources and economic benefit with minimum cost of agricultural measures. Phytoextracting trace elements （e.g., As, Cd, Ni, and Zn） using hyperaccumulator species is more suitable for slightly and moderately polluted sites, and phytomining of Ni from serpentine soils has shown a great potential to extract Ni-containing bio-ores of economic interests. We conclude that appropriate combinations of soil types, plant species/cultivars, and agronomic practices can restrict trace metal transfer to the food chain and/or extract energy and metals of industrial use and allow safe agricultural activities.

关键词： agronomic practices food safety hyperaccumulator phytoremediation trace element

In Silico Docking of Rhodanine Derivatives and 3D-QSAR Study to Identify Potent Prostate Cancer Inhibitors

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Computational Chemistry 2022年第2期10卷 19-52页

作者： Koffi Alexis Respect Kouassi Adenidji Ganiyou Diomande Gbe Gondo Didier Anoubilé Benié Ziao Nahossé laboratoire de Thermodynamique et de Physico-Chimie du Milieu UFR SFA Université Nangui Abrogoua Abidjan C&#244 te d’Ivoire laboratoire de Constitution et de Réaction de la matière UFR-SSMT Université Félix Houphou&#235 t-Boigny Abidjan C&#244 te d’Ivoire laboratoire de Chimie bio-Organique et de Substances Naturelles UFR-SFA Université Nangui Abrogoua Abidjan C&#244 te d’Ivoire

The 3VHE protein is considered as a potential target for the treatment of prostate cancer. In order to find new 3VHE inhibitors, pharmacophore models based on the molecular structure of rhodanine derivatives and a three-dimensional quantitative structure-activity relationship model (3D-QSAR) have been developed and validated by different methods. The 3D-QSAR model was evaluated for its predictive performance on a diverse test set containing 18 prostate cancer inhibitors. It presents very interesting internal and external statistical validation parameters (SD = 0.081;R2 = 0.903;Q2 = 0.869;;F = 247.2). This result suggests that the 3D-QSAR combinatorial model can be used to search for new 3VHE inhibitors and predict their potential activity. Based on the combinatorial pharmacophore model, a virtual screening of the Enamine database was performed. Compounds selected after virtual screening were subjected to molecular docking protocols (HTVS, SP, XP and IFD). Twenty new active compounds have been identified and their absorption, distribution, metabolism and excretion (ADME) property calculated using Schr?dinger’s Qikprop module. These results suggest that these new compounds could constitute new chemical starting points for further structural optimization of 3VHE inhibitors.

关键词： Rhodanine Pharmacophores 3D-QSAR Molecular Docking