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Spatial patterns of a savanna palm tree Borassus aethiopum and its temporal variability

Journal of Plant Ecology 2022年第5期15卷 1049-1064页

作者： amara sidiki traoré Kouadio Ignace Kouassi Moussa Koné Jacques Gignoux Sébastien Barot UFR des Sciences de la Nature UniversitéNANGUI ABROGOUACentre de Recherche en EcologieStation d'Ecologie de LamtoAbidjanCote d'Ivoire Institute of Ecology and Environmental Sciences Paris Sorbonne UniversiteUniversitéde ParisUPECCNRSINRAIRDParisFrance

The spatial distributions and associations of plant species in a stand can provide essential information about their ***,since tree spatial distribution and association depend on factors that operate at different scales,disentangling the effects of environmental heterogeneity and plant-plant interactions requires the choice of a suitable null model for spatial *** analyzed the spatial distributions of the same savanna palm tree populations that were studied,the underlying hypothesis being that these distributions have changed in 20 *** remove the effect of large-scale environmental heterogeneity,the inhomogeneous L-function under the heterogeneous Poisson null model was *** showed:(i)unlike 20 years ago,adults had a regular distribution instead of an aggregated distribution in the grass savanna;(i)although the spatial distribution of seedlings and juveniles was always aggregated,we observed a decrease in the size of the aggregates(intensities);ili)except for juveniles,no other stages were associated with nutrient-rich patches,which was also different 20 years ago;(iv)we did not observe any particular difference in structure between two study sites,only that female palm trees were spatially associated with entire-leafed seedlings in the reserve while they were spatially independent in the rural *** study supports the hypothesis that the spatial distributions have partially changed,and that the management of spatial heterogeneity has improved and given more precision in the results.

关键词： spatial heterogeneity palm trees heterogeneous Poisson(HP)null model spatial distribution spatial association Lamto reserve

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Solvent-free synthesis of some new 2-(3,5-dimethoxy-4-methylphenyl)-5-aryl-1,3,4-oxadiazoles

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Chinese Chemical Letters 2008年第4期19卷 423-427页

作者： Aamer Saeed amara Mumtaz Department of Chemistry Quaid-I-Azam UniversityIslamabad 45320Pakistan

An expeditious microwave-accelerated one-step synthesis of some new 2-（3,5-dimethoxy-4-methylphenyl）-5-aryl-1,3,4- oxadiazoles by reaction of 3,5-dimethoxy-4-methyl hydrazide with different carboxylic acids in prese... 详细信息

关键词： 1,3,4-Oxadiazoles 3,5-Dimethoxy-4-methylhydrazide Solvent-free

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Microwave-accelerated synthesis of some 1-aroyl-3,5-dimethylpyrazoles

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Chinese Chemical Letters 2008年第11期19卷 1305-1308页

作者： Aamer Saeed amara Mumtaz Department of Chemistry Quaid-I-Azam UniversityIslamabad 45320Pakistan

Rapid and highly efficient synthesis of some 1-aroyl-3,5-dimethylpyrazoles is achieved by the cyclocondensation of corresponding aroyl hydrazides with 2,4-pentanedione in the absence of solvent and catalyst, under microwave irradiation. The reaction proceeds rapidly and is completed within 40-70 s giving a series of 1-aroyl-3,5-dimethylpyrazoles derivatives in high yields. All of the compounds have been characterized by FTIR, ^1H NMR, and mass spectroscopy.

关键词： 1,3-Dimethylpyrazole 2,4-Pcntanedione Hydrazidcs Microwave-accelerated

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Synthesis and structural characterization of a new yttrium phosphate: Na_(2.5)Y_(0.5)Mg_7(PO_4)_6 with fillowite-type structure

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Journal of Rare Earths 2010年第4期28卷 481-487页

作者： Hasna Jerbi Mourad Hidouri Mongi Ben amara R.U. Inorganic materials Faculty of Sciences 5019 Monastir Tunisia

A new phosphate, Na2.5Y0.5Mg7(PO4)6 was synthesized as single crystals by the flux method and as a powdered sample by the Pechini technique, and investigated by single crystal X-ray diffraction, charge distribution (CD) and 31P NMR spectroscopy. This compound crystallized in the rhombohedral space group R 3 and its equivalent hexagonal cell had the following parameters: a=1.4976(6) nm, c= 4.2599(7) nm, Z=18. The structure consisted of MgO5, MgO6, YO6, (Na,Y)O8 and NaOx (x=6, 7 and 9) polyhedra which were li...

关键词： phosphate fillowite X-ray diffraction 31P NMR spectroscopy rare earths

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First-principles study of the new potential photovoltaic absorber:Cu_2MgSnS_4 compound

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Chinese Physics B 2017年第7期26卷 294-304页

作者： Belmorsli Bekki Kadda amara Mohammed El Keurti Laboratoire d'étude physico-chimique Université Dr.Moulay Tahar de Saida

The structural, electronic, optical, and elastic properties of Cu_2MgSnS_4 in four crystalline phases（wurtzite-stannite（WS）, stannite（ST）, kesterite（KS）, and primitive-mixed Cu Au（PMCA）） are investigated using density functional theory（DFT） in the framework of the full potential linearized augmented plane wave plus local-orbitals（FP-LAPW＋lo） method within the generalized gradient approximation based on the Perdew 2008 functional（GGA-PBEsol）. For each phase, the structural parameters, bulk modulus, and its pressure derivative are calculated. The relative stability of these phases is also discussed. In addition, the elastic constants have been calculated in order to investigate the mechanical stability of all phases. Moreover, the anisotropy factor, shear modulus, Young＇s modulus, Lame＇s coefficient, and Poisson＇s ratio have been estimated from the calculated single crystalline elastic constants. For the band structure, the density of states and optical properties of the exchange and correlation effects are treated by the Tran-Blaha modified Becke-Johnson potential to give a better description of the band-gap energies and optical spectra. The obtained results are compared with available experimental data and to other theoretical calculations.

关键词： quaternary chalcogenide semiconductor elastic constants electronic properties optical properties

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Analysing the Factors Affecting Prenatal Visits in Guinea: A Secondary Study of the 2018 Demographic and Health Survey (DHS)

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Open Journal of Obstetrics and Gynecology 2023年第8期13卷 1417-1431页

作者： Abdourahamane Diallo Almamy amara Toure Aboubacar sidiki Magassouba Diao Cisse Younoussa Sylla Ibrahima Barry Department of Gynaecology-Obstetrics Ignace Deen National Hospital Conakry Guinea Faculty of Health Sciences and Technologies Gamal Abdel Nasser University of Conakry Conakry Guinea National Center for Training and Research in Rural Health of Mafèrinyah Forécariah Guinea

Background: Despite persistent efforts to improve maternal health through various interventions, Guinea faces challenges in achieving adequate antenatal care coverage (ANC). This study aims to identify the key factors influencing prenatal consultation in Guinea. Methods: A secondary analysis was conducted on Guinea’s 2018 Demographic and Health Survey (DHS) data. The study sample comprised women aged 15 - 49 who participated in the survey. Logistic regression was employed to identify the determinants of ANC utilisation. Results: Most women in the sample (59.1%) were aged between 18 and 30, resided in rural areas (69.8%), had no formal education (71.0%), had low incomes (43.4%), were married (91.4%), relied on the radio for information (63.4%), and were employed at the time of the survey (68.0%). The study identified several factors acting as barriers to meeting the recommended four ANC visits, including low education levels, with odds ratios (OR) of 0.43 (p = 0.011) for those with no schooling and 0.48 (p = 0.046) for those with primary-level education. Lack of radio access also negatively influenced ANC utilisation with an OR of 0.72 (p = 0.012). Additionally, delayed timing of the first ANC visit in the second trimester had an OR of 0.36 (p 0.001), while in the third trimester, the OR was 0.04 (p 0.004). On the other hand, factors that facilitated achieving the recommended four ANC visits included having an average wealth quintile with an OR of 1.63 (p = 0.002) and being wealthy with an OR of 2.30 (p 0.001). Conclusion: This study underscores the negative association between low education level and poverty with ANC utilisation among pregnant women in Guinea. These findings emphasise the need for targeted interventions to address the barriers faced by vulnerable populations and improve maternal healthcare access and utilisation in the country.

关键词： Determinants ANC DHS Guinea

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Study of Cofactors Associated with Precancerous High-Grade Cervical Lesions at the Teaching Hospital Gabriel Touré, 2010 to 2015

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Surgical Science 2019年第9期10卷 328-337页

作者： Fané Seydou Bocoum Amadou Sissoko Abdoulaye traoré Soumana Oumar Sanogo Siaka amara Mamadou Sima Kouma Aminata traoré Alassane Tegueté Ibrahima traoré Youssouf Mounkoro Niani Teaching Hospital Gabriel Toure Bamako Mali

Introduction: High grade dysplasia of the cervix has a high incidence and can progress to cervical cancer. The aim was to study cofactors associated with high-grade cervical dysplasia. Methodology: This was a retrospective case-control study without matching. Women with high grade dysplasia were the cases while those with a normal screening test represented the controls. The study took place at the Gabriel Touré University Hospital Center in Bamako. We included 351 cases and 420 controls. The capture and analysis were performed using the SPSS 20 software. A univariate and multivariate logistic regression analysis was performed for the analysis of risk cofactors. The statistical tests used were the odds ratio and its confidence interval and the statistical significance threshold was set at p Results: In univariate analysis, the co-factors statistically significantly associated with the occurrence of high-grade dysplasia were parity 0.6 (0.5 - 0.9), gestational 0.7 (0.5 - 0.9), smoking of the spouse 3.4 (1.1 - 11.3), the non-schooling 1.4 (1.2 - 2.1). In multivariate analysis after adjusting for confounding factors, two co-factors have significantly increased the risk of high-grade dysplasia: lack of schooling 1.4 (1.2 - 2.0) and polygamy 1.5 (1.4 - 2.5). Conclusion: At the end of this study, polygamy and lack of schooling were the main risk factors. The prevention of cervical cancer will go through the education of girls and women as well as communication for behavioral change and social change.

关键词： High Grade Dysplasia Cofactor Cervical Cancer Teaching Hospital Gabriel Touré

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Appendicular Mucocele: About a Case Observed in Bamako

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Surgical Science 2022年第12期13卷 577-584页

作者： amara Coulibaly Abdoul Karim Simaga Moussa Sissoko Sekou Koumare sidiki Konare Mamedy Doumbia Zimogo Zié Sanogo Department of Surgery “A” of the University Hospital Center (CHU) of Point-G Bamako Mali Surgery Department of the Mother-Child University Hospital Center (CHU-ME) “Luxembourg” Bamako Mali

It is a globally rare condition that can present in a variety of clinical syndromes or can occur as an incidental surgical finding. It poses the double problem of its possible malignancy and the risk of gelatinous disease of the peritoneum in the event of perforation. We report a case treated in the “A” Surgery Department of the Point-G University Hospital Center (CHU) in Mali in 2022. It was a 62-year-old woman, a housewife who presented to the department. “A” surgery at the Point G University Hospital Center for pain in the iliac fossa. As a medical history, she was hypertensive on atenolol and a known diabetic on diet and metformin-based treatment, as well as symptomatic sickle cell disease (AS) and an undocumented history of peptic ulcer disease. The biological assessments revealed hyperleukocyte with granulocyte predominance. C-reactive protein was positive at 32 mg/l. Ultrasound revealed a 27 mm cystic dilation of the appendicitis in favor of appendicular mucocele. We proceeded with the appendix. The surgical specimen containing gelatinous fluid was removed and histological examination was in favor of a mucinous adenocarcinoma of the appendix.

关键词： Appendicular Mucocele Appendicular Tumor Bamako

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Na_2BaMg(PO_4 )_2:synthesis, crystal structure and europium photoluminescence properties

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Journal of Rare Earths 2013年第9期31卷 849-856页

作者： Amal Boukhris Mourad Hidouri Benoit Glorieux Mongi Ben amara UR:Inorganic Materials Faculty of ScienceUniversity of Monastir Institute for Condensed Matter Chemistry of Bordeaux CNRS University of Bordeaux I87Avenue of Dr.A.Schweitzer33608 Pessac-CedexFrance

Na2BaMg（PO4）2 was synthesized and characterized by X-ray diffraction, differential thermal analysis （DTA）, 31p NMR spectroscopy and photoluminescence measurements. This compound crystallized in the P3 ml space group of the trigonal system with the parameters of equivalent hexagonal cell a=0.5305（1） nm and c=0.6986（3） nm. The structure showed a perfect isotipysm with the mineral glaserite KaNa（SO4）2. Thus, it exhibited a lamellar framework which could be described as the stacking along the [001] direc- tion of [MgP2O84-]∞ layers of comer sharing MgO6 polyhedra and PO4 tetrahedra. The Ba2＋ cations were located within the interlayer space, while the Na＋ ones were found in large cavities bound to the layers. The DTA analysis showed that this compound melt con- gruently at 1385 K. The 31p NMR spectrum was consistent with the presence of a single phosphorus site in the structure. Optical properties were investigated for the 5% doped Eu3＋ and Eu2＋ phases. The trivalent europium was used as a local probe, replacing bar- ium while the divalent europium was used to examine whether this material could be used as an optical applications.

关键词： phosphate 31p NMR crystal structure europium photoluminescence rare earths

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FLK is an mRNA m^(6)A reader that regulates floral transition by modulating the stability and splicing of FLC in Arabidopsis

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Molecular Plant 2023年第5期16卷 919-929页

作者： Umme amara Jianzhong Hu Jing Cai Hunseung Kang Department of Applied Biology College of Agriculture and Life SciencesChonnam National UniversityGwangju 61186South Korea

N^(6)-methyladenosine(m^(6)A),which is added,removed,and interpreted by m^(6)A writers,erasers,and readers,respectively,is the most abundant modification in eukaryotic *** m^(6)A marks play a pivotal role in the regulation of floral transition in *** LOCUS K(FLK),an RNA-binding protein harboring K-homology(KH)motifs,is known to regulate floral transition by repressing the levels of a key floral repressor FLOWERING LOCUS C(FLC)in ***,the molecular mechanism underlying FLK-mediated FLC regulation remains *** this study,we identified FLK as a novel mRNA m^(6)A reader protein that directly binds the m^(6)A site in the 3ʹ-untranslated region of FLC transcripts to repressing FLC levels by reducing its stability and ***,FLK binding of FLC transcripts was abolished in vir-1,an m^(6)A writer mutant,and the late-flowering phenotype of the flk mutant could not be rescued by genetic complementation using the mutant FLKm gene,in which the m^(6)A reader encoding function was eliminated,indicating that FLK binds and regulates FLC expression in an m^(6)A-dependent ***,our study has addressed a long-standing question of how FLK regulates FLC transcript levels and established a molecular link between the FLK-mediated recognition of m^(6)A modifications on FLC transcripts and floral transition in Arabidopsis.

关键词： Arabidopsis thaliana RNA methylation m^(6)A reader FLK floral transition FLC

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