Multi-Scale Statistical Approach of the Elastic and Thermal Behavior of a Thermoplastic Polyamid-Glass Fiber Composite

The strong heterogeneity and the anisotropy of composite materials require a rigorous and precise analysis as a result of their impact on local properties. First, mechanical tests are performed to determine the macroscopical behavior of a polyamid glass  fiber composite. Then we focus on the influence of the heterogeneities of the microstructure on thermal and mechanical properties from finite element calculations on the real microstructure, after plane strain assumptions. 100 images in 10 different sizes (50, 100, 150, 200, 250, 300, 350, 400, 450, 600 pixels) are analysed. The influence of the area fraction and the spatial arrangement of fibers is then established. For the thermal conductivity and the bulk modulus the fiber area fraction is the most important factor. These properties are improved by increasing the area fraction. On the other hand, for the shear modulus, the fibers spatial arrangement plays the paramount role if the size of the microstructure is smaller than the RVE. Therefore, to make a good prediction from a multi-scale approach the knowledge of the RVE is fundamental. By a statistical approach and a numerical homogenization method, we determine the RVE of the composite for the elastic behavior (shear and bulk moduli), the thermal behavior (thermal conductivity), and for the area fraction. There is a relatively good agreement between the effective properties of this RVE and the experimental macroscopical behavior. These effective properties are estimated by the Hashin-Shtrikman lower bound

Etude de la stabilité et de l’acceptabilité du CSB ++ (Corn-Soya Blend) au Niger

L’objectif de cette étude est de tester la stabilité et l’acceptabilité du CSB++, une farine améliorée pour répondre à la crise nutritionnelle récurrente au Niger. Ainsi, une démarche à deux volets a été choisie: Un volet stabilité du CSB++ et un volet acceptabilité du produit au niveau communautaire. Ce dernier volet s’est déroulé dans 2 villages et a concerné 206 couples mères – enfants (âgés de 12 – 23 mois). Les résultats ont révélé que le CSB++, farine jaune, a une teneur en eau (9,26% - 5,5%) largement inférieure au seuil critique (12%) et uneacidité grasse (0,01 – 0,02) qui reste acceptable par rapport aux normes (< 0,05). Le CSB++ est exempt de bactéries indicatrices de mauvaises hygiènes et pratiques, et la flore totale demeure inférieure au seuil FAO.Aussi, le suivi de la stabilité révèle que la farine reste consommable et ceci plusieurs jours à la température ambiante. Par ailleurs, la bouillie du CSB++ a été consommée totalement par 87,76% d’enfants au niveau des 2 villages et le score d’acceptabilité est maximal tant pour la farine que pour la bouillie. Le CSB++ peut être considéré comme un produit alimentaire stable, efficace et accepté par la communauté.Mots clés: Stabilité, acceptabilité, CSB++, Niger

Efficient Quantum Analytic Nuclear Gradients with Double Factorization

Efficient representations of the Hamiltonian such as double factorization drastically reduce circuit depth or number of repetitions in error corrected and noisy intermediate scale quantum (NISQ) algorithms for chemistry. We report a Lagrangian-based approach for evaluating relaxed one- and two-particle reduced density matrices from double factorized Hamiltonians, unlocking efficiency improvements in computing the nuclear gradient and related derivative properties. We demonstrate the accuracy and feasibility of our Lagrangian-based approach to recover all off-diagonal density matrix elements in classically-simulated examples with up to 327 quantum and 18470 total atoms in QM/MM simulations, with modest-sized quantum active spaces. We show this in the context of the variational quantum eigensolver (VQE) in case studies such as transition state optimization, ab initio molecular dynamics simulation and energy minimization of large molecular systems.Comment: 22 pages, 5 figure

Coinage metals trinuclear metallocycles: old and new aspects of this class of compounds

Coinage metals trinuclear metallocycles: old and new aspects of this class of compounds Galassi R. a, Oumarou C. S. a, Omary A. M. b, Nesterov V. b, Burini A.a aSchool of Science and Technology, Chemistry Division, University of Camerino, Via S. Agostino 1, 62032 Camerino; e-mail: [email protected] b Department of Chemistry, University of North Texas, Denton, 1155 Union Circle, TX 76203, USA; e-mail: [email protected] Azoles such as imidazoles and pyrazoles are optimal bridging ligands to obtain C,N or N,N trinuclear coinage metals metallocycles. Since past decade till now, few worldwide research groups including us have focused their attention to their synthesis and characterization.[1] Moreover, the photophysical properties[2] the extended network of metallophilic bondings in the supramolecular structure and the pi-acid/pi-base chemistry[3] of these compounds directed the research to theoretical studies bringing to a better interpretation of the experimental behaviors.[4] Here we report the synthesis of new coinage metals metallocycles and their spectroscopic characterizations highlighting points of continuity with the previous analogs and new features for new perspective research lines. As in example, the 1-vinylimidazole resembles the acid-base chemistry of the 1-benzylimidazole gold(I) metallocycle, while substitution in position 4,5 of 1-benzylimidazole with electron-withdrawing group, do not allow the formation of metallocycles with the same synthethic route and mononuclear gold(I) derivatives have been obtained. The nature of the heterocycle and of the substituents, in addition to their position in the azolate ligand defines and tunes the properties of the final products. References: 1) Galassi, R.; Burini, A.; Omary-Rawanashed, M., Omary, M. A., Comm. Inorg. Chem. 2014, in submission. 2) Rawashdeh-Omary, M. A.; Omary, M. A.; Fackler Jr, J. P, Galassi R., Pietroni, B. R.; Burini, A. J. Am. Chem. Soc 2001, 123; 9689-9691. 3) Burini, A.;. Fackler Jr, J. P; Galassi R., Grant, T. A.. Omary, M. A; Rawashdeh-Omary, M. A.; Pietroni, B. R.; Staples R. J. J. Am. Chem. Soc., 2000; 11264-11265. 4) Galassi, R.; Ricci, S.; Burini, A.; Macchioni, A; Marmottini, F.; Tekarli, S. M.; Nesterov, N.V.; Omary, M. A. Inorg. Chem. 2013, 52, 14124-14137

Usages Socioeconomiques Des Espèces Ligneuses Au Sahel: Cas De Guidan Roumdji Au Niger

Woody species are of multiple use in the department of Guidan- Roumdji, in Niger. The present study carried out in Garin-yahaya and Tsayin-daka aims to identify the woody species, their different uses and to determine their present state. Data collection methodology consisted of a floristic inventory at the level of 80 plots and ethnobotanical surveys on a sample of 250 respondents. 46 species, divided into 38 genera and 22 families, were recorded. There were 24 species used in food, 19 fodder species and 38 others species used in the treatment of several ailments in the area. Also, in handicrafts and construction, a dozen species are used respectively against 19 others species in the production of wood energy. These diverse and wide-ranging uses, associated with the effects of climate change, affect the woody species populations. Thus, in the area, 25 species are declared extinct, 18 and 14 others are respectively considered threatened and rare. The study also reported on woody species management practices in the area, including the conservation of 7 local species and the introduction of 11 exotic species because of various products and services they provide. Also, 96% of the local population practices the trees’ farming natural regeneration management (FNRM) in their farms for various reasons. This would be a start in the sustainable and rational management of forest resources in the area with the maintenance of several woody species in the area

Supramolecular Chemistry and photophysical Properties of a New Gold (I) Cyclic Trinuclear Complex, [Au(µ-C2,N3-1-vinylimidazole)]3

Supramolecular Chemistry and photophysical Properties of a New Gold (I) Cyclic Trinuclear Complex, [Au(µ-C2,N3-1-vinylimidazole)]3 R. Galassia, A. Burinia, C. S. Oumaroua, V. N. Nesterov b, M. A. Omary b. a Dipartimento di Scienze Chimica, Università di Camerino, Via Sant Agostino, 1, 62032 Camerino, Italia b Department of Chemistry, University of North Texas, Denton, TX 76203, USA email: [email protected] In the past years several cyclic trinuclear complexes (CTC’s) have been synthetized and characterized on the basis of the capacity of d10 transition metal ions to give bicoordinated linear compounds. This intriguing class of compounds display pi-acid/ pi-base properties that can be finely tuned by: the nature of the metal, the substituents on the ligand or the ligand itself. [1] These complexes are attractive building blocks to obtain supramolecular compounds showing interesting photopysical properties [2] or heterobimetallic cyclic trinuclear complexes with potential use in mixed-metal catalysis [3]. Here we report the synthesis of a novel gold (I) CTC, [Au(µ-C2,N3-1-vinylimidazole)]3, and the study of some photophysical properties of its supramolecular derivatives obtained by the intercalation of metal ions in between the metallocycles. [1] S.M. Terkali, T.R. Cundari, M.A. Omary, J. Am. Chem. Soc. 2008, 130, 1669 [2] a) A. Burini, R. Bravi, J. P. Fackler Jr, Galassi R., T. A. Grant, M. A. Omary, B. R. Pietroni, R. J. Staples . Inorg. Chem. 2000, 39; 3158.b) Burini A, Fackler J. P, JR, Galassi R., Grant T. A, Omary M. A, Rawashdeh-Omary M. A, Pietroni B. R, Staples R.J. J. Am. Chem. Soc. 2000, 122; 11264. [3] A. Mohamed, R. Galassi, F. Papa, A. Burini, J.P. Fackler , Jr. Inorg. Chem. 2006, 45, 7770-7776 [5] R. Galassi, S. Ricci, A. Burini, A. Macchioni, L. Rocchiagiani, F. Marmottini, S.M. Terkali, V.N. Nesterov, M.A. Omary, Inorg. Chem. 2013, 52, 14124-1413

Mentoring New Faculty: An Appreciative Approach

During this period of dramatic social and institutional change in higher education, positive induction and ongoing support for early-career and faculty members new to the campus community is essential. Disparities remain in the recruitment, development, retention, and promotion of diverse faculty, in large part because of the lack of mentoring. The purpose of this article is to enhance approaches for supporting early-career and otherwise new faculty members. Based upon the principles and processes of Appreciative Inquiry, the Appreciative Mentoring Model is presented. Each of the Appreciative Inquiry “D-phases” is described in detail together with research-based best practices that can be employed in mentoring. Prompts, questions, and specific examples designed to support the growing need for a more collaborative, fluid, dynamic, and transformative approach to mentoring are provided.

The conservative treatment of giant omphalocele by tanning with povidone iodine and aqueous 2% eosin solutions

Aim: The aim of this work was to report the result of nonoperative management of giant omphalocele by dressing with povidone iodine and aqueous eosin in Niger.Patients and methods: This prospective study was conducted over 5 years (January 2011 to December 2015) in the Departments of Pediatric Surgery in the country. The procedure consisted of applying povidone iodine at the initial phase of the treatment as inpatient followed by aqueous eosine solution application as outpatient, which was continued up to complete epidermization. The clinical aspects, the complications and the mortality of omphalocele were discussed.Results: The study included about 13 patients; the mean age at presentation was 1.7 days (range: 3 h–8 days). The delivery was at home in 38.46% of the cases (five out of 13). The average birth weight was 2810 g. Associated congenital abnormalities were found in 46.15% of cases (six out of 13). The mean initial hospitalization duration was 8 days. The average length of complete epidermization duration was 9±2 weeks. The secondary surgical cure was realized in eight patients. The morbidity rate was 30.77% (four out of 13). The mortality rate was 23.07% (three out of 13).Conclusion: The conservative treatment of giant omphalocele through the application of povidone iodine and aqueous eosine is effective and cost-effective. This procedure should be privileged in our limited resources Health centers where pediatric intensive care unit are lacking.Keywords: conservative management, dressing, epidermization, omphalocel

Diversité des champignons basidiomycètes à carpophores inféodés à certaines espèces des Caesalpiniaceae du Parc National du W du Niger (Afrique de l’Ouest)

Objectif : Ce travail a pour objectif de contribuer à la connaissance des macromycètes du Niger.Méthodologies et résultats : L’étude a été conduite dans le Parc National du W du Niger qui se trouve dans la zone la plus riche en biodiversité du pays. Ainsi, un inventaire des champignons a été réalisé dans quatre types de formations végétales. Il s’agit de la savane arborée plus ou moins arbustive à Afzelia africana et Combretum glutinosum (Site 1) ; de la forêt claire à Isoberlinia doka et Anogeissus leiocarpa (Site 2) ; de la forêt claire à Isoberlinia doka et Berlinia grandiflora (Site 3) et la savane arborée plus ou moins arbustive à Burkea africana et Terminalia avicennioides (Site 4). Au total, cinquante-six (56) espèces de macromycètes ont été recensées sur les sites explorés. Les espèces ectomycorhiziennes s’élèvent à vingt-quatre (24) dont dix-sept (17) dans le site 1, onze (11) au niveau du site 3, trois (3) dans le site 2 et une (1) sur le site 4. Ceci est lié à la présence des certaines essences forestières de la famille des Caesalpiniaceae, à savoir A. africana, I. doka et B. grandiflora.Conclusion et application des résultats : cinq (5) espèces fongiques ectomycorhiziennes (Amanita odorata, A. subviscosa, Lactarius gymnocarpoides, Phylloporus purpureus et Russula albofloccosa) sont communes à la fois à la savane arborée plus ou moins arbustive à A. africana et C. micranthum et à la forêt claire à I. doka et B. grandiflora.Mots-clefs : Macromycètes, Basidiomycètes, Écologie, Caesalpiniaceae, Parc National du W, Niger, Afrique de l’Ouest