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全尾砂-粗骨料膏体早期抗压强度影响规律及固化机理

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中南大学学报（自然科学版） 2020年第2期51卷 478-488页

作者：尹升华刘家明邵亚建张海胜 armelle belibi 寇永渊北京科技大学金属矿山高效开采与安全教育部重点实验室北京100083 北京科技大学土木与资源工程学院北京100083 金川集团股份有限公司甘肃金昌737100

以某矿尾砂、废石、棒磨砂为实验材料,采用正交设计实验方法,研究膏体质量分数、水泥掺量、尾骨比(全尾砂、废石和棒磨砂质量比)、泵送剂掺量对充填体早期抗压强度的影响规律。对实验数据进行三维曲面可视化分析和多元非线性回归分析,... 详细信息

以某矿尾砂、废石、棒磨砂为实验材料,采用正交设计实验方法,研究膏体质量分数、水泥掺量、尾骨比(全尾砂、废石和棒磨砂质量比)、泵送剂掺量对充填体早期抗压强度的影响规律。对实验数据进行三维曲面可视化分析和多元非线性回归分析,最后根据实验结果对膏体固结性能的机理进行分析。研究结果表明:水泥掺量和质量分数是早期抗压强度的主要影响因素,m(全尾砂)꞉m(废石)꞉m(棒磨砂)以及泵送剂掺量存在最优值,最优值范围分别为5.0꞉2.5꞉2.5~4꞉3꞉3和1.5%~2.0%。多元非线性二次多项式回归拟合效果最佳,根据所选模型和主观权重T可知,所得目标函数f存在最大值和最小值,最大值为8.97 MPa,最小值为2.87 MPa,均满足7 d强度要求(R7≥2.5 MPa);粗骨料的掺入不仅能进一步提高早期抗压强度,而且粗骨料中的活性物质能与Ca(OH)2发生反应,起到部分胶凝效果。

关键词：粗骨料早期抗压强度膏体多元非线性回归固结机理

Petrographic and geochemical characterization of weathered materials developed on BIF from the Mamelles iron ore deposit in the Nyong unit, South-West Cameroon

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Acta Geochimica 2021年第2期40卷 163-175页

作者： Tessontsap Teutsong Jean Pierre Temga armelle Ayissi Enyegue Nicodeme Noel Feuwo Dieudonne Bitom Department of Earth Sciences University of Yaounde IP.O.Box 812YaoundeCameroon Ministry of Mines Industry and Technological DevelopmentYaoundeCameroon University of Dschang P.O.Box 96Dschang.Cameroon

Iron ore deposits hosted by Precambrian banded iron formation(BIF)are the most important source of mineable *** Cameroon,they are located in the southern part of the *** study reports the petrological and geochemical data of iron ores collected from a weathering profile in the Mamelles BIF deposit,SW *** profile is composed of three levels which are from the bottom to the top:the saprock,the ferruginous horizon,and the loose *** representative iron ore samples(rock fragments and loose clayey material)were collected along the profile and were subjected to petrographic and geochemical *** mineralogy consists of martite,goethite,quartz,and lesser amounts of hematite,magnetite,kaolinite,and *** presence of minerals such as kaolinite and goethite in the Mamelles iron ores suggests their supergene ***,the saprock is characterized by high iron content(70.25 wt%Fe_(2)O_(3) t),and low silica(26.38 wt%SiO_(2))and alumina(1.14 wt%Al_(2) O_(3)).The rock fragments collected from the ferruginous horizon display higher Fe2 O3 t(72-76.40 wt%),Al_(2) O_(3)(2.80-5.43 wt%),and lower SiO_(2)(16.70-18.35 wt%)contents,suggesting the leaching of silica during the enrichment *** loose clayey samples collected from both the ferruginous horizon and the upper loose horizon show lower iron and higher silica *** normalized to the underlying BIF saprock,both rock fragments and loose clayey ores display LREE enrichment,suggesting that they formed through supergene ***,most of the Mamelles iron ores are classified as medium-grade ores and a few display acceptable contents in ***,this petrological and geochemical study of the Mamelles iron ores revealed encouraging *** its strategic location near the deep seaport,the deposit should be investigated in more detail for its mining potential.

关键词： Mamelles BIF Medium-grade iron ore Supergene origin Nyong unit Cameroon

Experimental manipulation of reproductive tactics in Seba’s short-tailed bats:consequences on sperm quality and oxidative status

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Current Zoology 2019年第6期65卷 609-616页

作者： Magali MENIRI Florence GOHON Ophelie GNING Gaetan GLAUSER armelle VALLAT Nicolas JFASEL Fabrice HELFENSTEIN Laboratory of Evolutionary Ecophysiology Institute of BiologyUniversity of NeuchatelSwitzerland Neuchatel Platform of Analytical Chemistry University of NeuchatelSwitzerland Leibniz Institute for Zoo and Wildlife Research Germany

To reproduce,males have to fertilize the female’s eggs,sometimes in competition with ejaculates of other *** species where males display alternative reproductive tactics,whereby territorial males secure mating and non-territorial males have to sneak copulations,the latter might be expected to invest relatively more resources towards sperm quality compared with the territorial *** cells are especially vulnerable to oxidative stress,which reduces male ***,antioxidant resources are expected to modulate sperm quality,and might be allocated differently between reproductive *** test the link between reproductive tactics,redox profile and sperm quality,we experimentally induced changes in the reproductive tactics of 39 captive males Seba's short-tailed bats Carollia *** monitored the blood and ejaculate oxidative balance,and the sperm quality before,7 days and 21 days after the manipulation of reproductive *** ejaculates'oxidative damage was negatively related to sperm velocity,males exhibited similar blood and ejaculates redox profiles and similar sperm quality,regardless of their reproductive ***,these results arise as a consequence of some constraints having been lifted during the *** results also suggest that,in Seba's short-tailed bats,the expression of alternative reproductive tactics is not subjected to strong oxidative ***,our results could reflect an absence of trade-off between pre-and post-copulatory traits in harem males,as they could be selected to invest both in female attraction and sperm quality,as a consequence of their inability to fully monopolize females.

关键词： oxidative stress sperm competition alternative reproductive tactics Carollia perspicillata

Aphis （Hemiptera： Aphididae） species groups found in the Midwestern United States and their contribution to the phylogenetic knowledge of the genus

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Insect Science 2014年第3期21卷 374-391页

作者： Doris M. Lagos David J. Voegtlin armelle Coeur d'aciert Rosanna Giordano Department of Entomology University of Illinois at Urbana-Champaign 320 Morrill Hall 505 S. Goodwin Avenue Urbana IL 61801 Illinois Natural History Survey Prairie Research Institute University of Illinois at Urbana-Champaign 1816 S Oak Street Champaign IL 61820 USA INRA-UMR 1062 CBGP (INRA IRD CIRAD Montpellier SupAgro) Centre de Biologie pour la Gestion des Populations Campus International de Baillarguet CS 30 016 F-34 988 Montferrier-sur-Lez France

A phylogeny of the genus Aphis Linnaeus, 1 758 was built primarily from specimens collected in the Midwest of the United States. A data matrix was constructedwith 68 species and 41 morphological characters with respective character states of alate and apterous viviparous females. Dendrogram topologies of analyses performed usingUPGMA （Unweighted Pair Group Method with Arithmetic Mean）, Maximum Parsimony and Bayesian analysis of Cytochrome Oxidase I, Elongation Factor 1-α and primary endosymbiont Buchnera aphidicola 16S sequences were not congruent. Bayesian analysis strongly supported most terminal nodes of the phylogenetic trees. The phylogeny wasstrongly supported by EFI-α, and analysis of COl and EFI-α molecular data combined with morphological characters. It was not supported by single analysis of COI or Buch-hera aphidicola 16S. Results from the Bayesian phylogeny show 4 main species groups： asclepiadis,fabae, gossypii, and middletonii. Results place Aphis and species of the generaProtaphis Bōrner, 1952, Toxoptera Koch, 1856 and Xerobion Nevsky, 1928 in a monophyletic clade. Morphological characters support this monophyly as well. The phylogenyshows that the monophyletic clade of the North American middletonii species group belong to the genus Protaphis： P. debilicornis （Gillette ＆ Palmer, 1929）, comb. nov., P. echinaceae（Lagos and Voegtlin, 2009）, comb. nov., and P. middletonii （Thomas, 1879）. The genus Toxoptera should be considered a subgenus of Aphis （stat. nov.）. The analysis also indicatesthat the current genus Iowana Frison, 1954 should be considered a subgenus of Aphis （stat. nov.）.

关键词： aphid host plant morphology phylogenetic relationship sequence divergences synonym

Regulatory and Functional Aspects of Indolic Metabolism in Plant Systemic Acquired Resistance

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Molecular Plant 2016年第5期9卷 662-681页

作者： Elia Stahl Patricia Bellwon Stefan Huber Klaus Schlaeppi Friederike Bernsdorff armelle Vallat-Michel Felix Mauch Jurgen Zeier Department of Biology Heinrich Heine University Dusseidorf Universiyatsstraβ 1 40225 Dusseidorf Germany Plant Biology Section University of Fribourg Route Albert Gockel 3 1700 Fribourg Switzerland Institut de Chimie Unlversite de Neuchatel Avenue Bellevaux 51 2007 Neuchatel Swttzerland Cluster of Excellence on Plant Sciences (CEPLAS) Heinrich Heine University Dusseldorf Universitatsstraβe 1 D-40225 Dusseldorf Germany Agroscope Institute for Sustainability Sciences Reckenholzstrasse 191 CH-8046 Zurich Switzerland

Tryptophan-derived, indolic metabolites possess diverse functions in Arabidopsis innate immunity to microbial pathogen infection. Hers, we investigate the functional role and regulatory characteristics of indolic metabolism in Arabidopsis systemic acquired resistance （SAR） triggered by the bacterial pathogen Pseudomonas syringae. Indolic metabolism is broadly activated in both P. syringae-inoculated and distant, non-inoculated leaves. At inoculation sites, camalexin, indol-3-ylmethylamine （13A）, and indole-3-carboxylic acid （ICA） are the major accumulating compounds. Camalexin accumulation is positively affected by MYB122, and the cytochrome P450 genes CYP81F1 and CYP81F2. Local 13A production, by contrast, occurs via indole glucosinolate breakdown by PEN2- dependent and independent pathways. Moreover, exogenous application of the defense hormone salicylic acid stimulates 13A generation at the expense of its precursor indol-3-ylmethylglucosinolate （13M）, and the SAR regulator pipecolic acid primes plants for enhanced P. syringae-induced activation of distinct branches of indolic metabolism. In uninfected systemic tissue, the metabolic response is more specific and associated with enhanced levels of the indolics 13A, ICA, and indole-3-carbaldehyde （ICC）. Systemic indole accumulation fully depends on functional CYP79B2/3, PEN2, and MYB34/51/122, and requires functional SAR signaling. Genetic analyses suggest that systemi- cally elevated indoles are dispensable for SAR and associated systemic increases of salicylic acid. However, soil-grown but not hydroponically -cultivated cyp79b2/3 and pen2 plants, both defective in indolic secondary metabolism, exhibit pre-induced immunity, which abrogates their intrinsic ability to induce SAR.

关键词： indolic metabolism systemic acquired resistance Pseudomonas syringae Arabidopsis thaliana

Antimicrobial Activity of the Methanolic Extract and Compounds from the Stem Bark of Drypetes tessmanniana

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Chinese Journal of Integrative Medicine 2010年第4期16卷 337-343页

作者： Victor Kuete Marlise D.J.Dongfack armelle T.Mbaveng Marie-Christine Lallemand Hanh T.Van-Dufat Jean-Duplex Wansi Elisabeth Seguin Francois Tillequin Jean Wandji Department of Biochemistry Faculty of ScienceUniversity of Dschang.P.O.Box 67 DschangCameroon Department of Organic Chemistry Faculty of ScienceUniversity of Yaounde I.P.O.Box 812 YaoundeCameroon Laboratoire de Pharmacognosie de I'Universite Paris Descartes UMR/CNRS N° 8638Faculte des Sciences Biologiques et Pharmaceutiques4-Avenue de I'Observatoire75006 ParisFrance Department of Biochemistry Faculty of ScienceUniversity of Yaounde IP.O.Box 812 YaoundeCameroon Department of Chemistry University of DoualaFaculty of ScienceP.O.Box 24157 DoualaCameroon Laboratoire de Pharmacognosie UFR de Medecine Pharmacie Rouen22-Bid Gambetta76183 Rouen Cedex 1France

Objective： To evaluate the antimicrobial activity of the methanol extract from the stem bark of Drypetes tessmanniana, fractions （DTB1-5） as well as compounds [friedelin （2）, 3,7-dioxofriedelane （3）, 3,15-dioxofriedelane （4）, 313 -O-（E）-3,5-dihydroxycinnamoyl-11 -oxo-olean-12-ene （6）, and 313,6 α -dihydroxylup- 20（29）-ene （7）. Methods： Agar disc diffusion was used to determine the sensitivity of the above samples, whilst the microdilution method was used for the determination of the minimal inhibitory concentration （MIC） and the minimal microbicidal concentrations （MMC）. Results： The diffusion test showed that the crude extract was able to prevent the growth of all tested organisms. All other samples showed selective activity. The inhibitory effect of the fraction DTB2 was noted on 63.7%, that of DTB1 and DBT3 on 54.6%, whilst DTB4 and DTB5 were active on 9.1% of the 11 tested organisms. The tested compounds prevented the growth of 81.8% of the tested microbial species for compounds 3 and 4, 36.7% for compound 6, and 18.2% for compound 7. The results of the MIC determinations indicated perceptible values for DTB and compound 4 on 81.8% of the tested organisms. For other samples, MICs were detected on 0-63.7%. The lowest MIC value （78.12 μg/mL） for the crude extract and fractions （DTB2） was observed on M. audouinii. The corresponding value for isolated compounds （156.25 μg/ mL） was noted with compounds 3 on S. faecalis and 4 on M. audouinii. The results of the MMC determination suggested that the microbicidal effect of most of the tested samples on the studied microorganisms could be expected. Conclusion： The methanol extract from the stem bark of Drypetes. tessmanniana （Euphorbiaceae） as well as some of the isolated compounds might be potential sources of new antimicrobial drues.

关键词： Drypetes tessmanniana Euphorbiaceae compounds antimicrobial activity

Fever among Children with Sickle-Cell Disease: Findings from the General Pediatric Ward of the Owendo Pediatric Hospital in Libreville, Gabon

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Open Journal of Pediatrics 2014年第4期4卷 262-268页

作者： Jean Koko Daniel Gahouma Simon Ategbo Cathérine Seilhan armelle Pambou André Moussavou General Pediatrics Service Owendo Peditric Hospital (OPH) Libreville Gabon Laboratory of Medical Biology Owendo Pediatric Hospital (OPH) Libreville Gabon Pediatrics Department Faculty of Medicine Health Sciences University (USS) Libreville Gabon

Sickle-cell disease (SCD) represents a substantial public health problem in Gabon. Fever is one of the principal reasons for the hospitalization of children afflicted by major sickle-cell disorder, since it can be a clinical reflection of severe infections that have the potential to become life threatening. Objectives: Identification of the main causes of fever in children with SCD in our clinical setting, with the aim of optimizing treatments. Patients and Methods: This is a retrospective study of all the medical files for children with SCD that were admitted to our ward, over a two year period, due to fever (>38.5°C) lasting more than 24 hours. Only those files that contained at least the following five fundamental medical examinations were retained for further evaluation: Complete Blood Count (CBC), blood smear, blood culture, urine culture and chest X-ray. Out of a total of 118 admissions (103 patients), 87 (73.7%) were due to the incidence of fever. The medical files of 11 patients were deemed to be unusable. Seventy-six episodes of fever were observed among 69 children, of which 42 were male and 27 female (sex ratio of 1.5). Among these, seven (10%) were admitted twice. Results: The age groups that were most affected included 12 - 18 year-olds (30 cases: 43.5%) and 6 - 12 year-olds (26 cases: 37.7%). The most common accompanying symptoms were bone and joint pain (43.4%), asthenia (22.4%), cough (19.7%), vomiting (17%) and headache (15.8%). The specific cause of the fever could not be pinpointed in 29 cases (38.1%). Aside from these cases, the main causes of fever were malaria (30.3%) and bronchopulmonary infections (22.4%). The white blood cell count was >20,000/mm3 in 47% of respiratory infections, 43.5% of the cases involving malaria and 55.2% of cases of fever with unknown cause. Hemoglobin levels were <5g/dl for 52.2% of the cases involving malaria and 22.6% for those of unknown origin. For four patients, all less than 10 years of age, the disease was fata

关键词： Sickle-Cell Disease Fever Malaria Acute Lower Respiratory Infections (ALRI) Gabon

Acute Malnutrition and Infection with the Human Immuno-Deficiency Virus (HIV) in Children Followed up at the Pediatrics University Hospital Charles de Gaulle: Evolution of Anthropometric Parameters on Antiretroviral Treatment

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Open Journal of Pediatrics 2016年第1期6卷 34-41页

作者： Aïssata Kaboré Sylvie armelle P. Ouédraogo Lassina Dao Fla Koueta Diarra Yé Service de Pédiatrie Médicale Centre Hospitalier Universitaire Pédiatrique Charles De Gaulle de Ouagadougou Ouagadougou Burkina Faso

Burkina Faso, a country with very scarce resources, undertook to fight against HIV infection. In 2013, according to UNAIDS, 110,000 persons were living in this country with HIV infection. 18,000 children among these persons were under 15. We conducted a retrospective study from January 2003 to December 2012 at the Pediatrics University Hospital Charles De Gaulle, Ouagadougou (CHUP CDG), Burkina Faso. The study aimed at assessing the children’s ponderal growth when under antiretroviral treatment. The children who were under 15 and who had been on antiretroviral treatment for at least 5 years were included in the study. Acute malnutrition concerned children whose height/weight ratio (H/W) was lower at -2 width type (or Z score) of the median of reference regarding age according to WHO. Two categories of malnutrition were outstanding in our study: moderate acute malnutrition, (-3 Z-score ≤ H/W -2 Z-score) and severe acute malnutrition (W/H -3 Z-score). The clinical and paraclinical data recorded during previous consultations were extracted from the ESOPE (Monitoring and follow-up of patients) data basis and exported to the ENA software and SPSS for their analysis. In total, 210 out of 529 children’s cases were considered. These children’s average age was 6.9 years. There were 55.7% of male and 44.3% of female children. HIV1 was found in 97.6% of the children against 2.4% for HIV2. In a 5 year follow-up, 46 among the children, namely 20.4% were on a second line protocol of antiretroviral treatment and 164 among them were still on a first line protocol of antiretroviral treatment. When they were admitted at hospital, 38% of the children showed characteristics of acute malnutrition. 17.8% of these children presented characteristics of severe form of acute malnutrition. During this 5-year follow-up, the average of the W/H index of the children gradually rised from -1.62 Z-score when being admitted to -0.18 Z-score at after a 60-month antiretroviral treatment. Our study sho

关键词： Acute Malnutrition HIV-Infected Children Antiretroviral Treatment Burkina Faso

Second-line therapy for advanced hepatocellular carcinoma with regorafenib or cabozantinib:Multicenter French clinical experience in real-life after matching

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World Journal of Gastrointestinal Oncology 2022年第8期14卷 1510-1527页

作者： Xavier Adhoute Marie De Matharel Laurent Mineur Guillaume Pénaranda Dann Ouizeman Clemence Toullec Albert Tran Paul Castellani armelle Rollet Valérie Oules HervéPerrier Si Nafa Si Ahmed Marc Bourliere Rodolphe Anty Department of Gastroenterology and Hepatology Hôpital Saint-JosephMarseille 13000France Department of Gastroenterology and Hepatology Hôpital Universitaire de l’ArchetNice 06000France Department of Oncology Institut Sainte-CatherineAvignon 84000France Department of Biostatistics AlphaBio LaboratoryMarseille 13000France

BACKGROUND Starting a second-line systemic treatment for hepatocellular carcinoma(HCC)is a common *** only therapeutic options in France are two broadspectrum tyrosine kinase inhibitors(TKIs),regorafenib(REG)and cabozantinib(CBZ),but no comparative real-life studies are *** To evaluate the progression-free survival(PFS)of patients treated with REG or CBZ,we investigated the disease control rate(DCR),overall survival(OS),and safety of both *** identify the variables associated with disease progression over *** A retrospective multicenter study was performed on the clinical data of patients attending one of three referral centers(Avignon,Marseille,and Nice)between January 2017 and March 2021 using propensity score *** and OS were assessed using the Kaplan-Meier *** analysis(MA)of progression risk factors over time was performed in matched-pair *** Fifty-eight patients 68(62-74)years old with HCC,Barcelona clinic liver cancer(BCLC)B/C(86%),Child-Pugh(CP)-A/B(24%)received REG for 3.4(1.4-10.5)mo as second-line *** patients 68(60-73)years,BCLC B/C(75%),CP-A/B(25%)received CBZ for 3.7(1.8-4.9)mo after first-line treatment with sorafenib[3(2-4)(CBZ)vs 4(2.9-11.8)mo(REG),P=0.0226].Twenty percent of patients received third-line *** matching,PFS and DCR were not significantly different after a median follow-up of 6.2(2.7-11.7)mo(REG)vs 5.2(4-7.2)mo(CBZ),P=*** was no difference in grade 3/4 toxicities,dose reductions,or *** OS of CP-A patients was 8.3(5.2-24.8)vs 4.9(1.6-11.7)mo(CP-B),P=*** MA of risk factors for progression over time identified C-reactive protein(CRP)>10 mg/L,neutrophil-to-lymphocyte ratio(NLR)>3,and aspartate aminotransferase(AST)>45 IU as predictive *** This multicenter indirect comparative study found no significant difference in PFS between REG and CBZ as second-line therapy for advanced *** levels of inflam

关键词： Hepatocellular carcinoma Regorafenib Cabozantinib C-reactive protein Neutrophillymphocyte ratio