Design and additive manufacturing of closed cells from supportless lattice structure

In nature, mesoscopic or microscopic cellular structures like trabecular bone, wood, shell, and sea urchin, can have high load-carrying capacity. These cellular structures with diverse shapes, forms and designs can be mainly classified into open and closed cell cellular structures. It is difficult to replicate these natural complex lattice structures with traditional manufacturing, but additive manufacturing (AM) technology development has allowed engineers and scientists to mimic these natural structures. Fabricating close cell lattice structures is still considered difficult due to the support structure within the lattices. This paper evaluates a novel way of fabricating a close cell lattice structure with a material extrusion process. The design eliminates the need for support structures and the subsequent post-processing required to remove them. A shell-shaped close cell lattice structure bio-mimicking a sea urchin shape was introduced for the load-bearing structure application. The mechanical properties of the proposed structure, including stiffness, deformation behavior and energy absorption, were compared with those of benchmarked honeycomb and open cell sea urchin (SU) lattice structures of the same density. SU lattice structures and honeycomb periodic lattice structures with varied sizes but the same morphology and fixed density were designed and printed in polylactic acid material (PLA). Their physical characteristics, deformation behavior, and compressive properties were investigated experimentally and via finite element analysis. The effect of the unit cell size on mechanical properties was studied and discussed, and the rankings of better performances were drawn. A possible application of the closed cell is for fabricating the load bearing structure; it can also be encapsulated within a fluid to impart strength and damping characteristics

Fusidic acid and clindamycin resistance in community-associated, methicillin-resistant Staphylococcus aureus infections in children of Central Greece

<p>Abstract</p> <p>Introduction</p> <p>In Greece, fusidic acid and clindamycin are commonly used for the empiric therapy of suspected staphylococcal infections.</p> <p>Methods</p> <p>The medical records of children examined at the outpatient clinics or admitted to the pediatric wards of the University General Hospital of Larissa, Central Greece, with community-associated staphylococcal infections from January 2003 to December 2009 were reviewed.</p> <p>Results</p> <p>Of 309 children (0-14 years old), 21 (6.8%) had invasive infections and 288 (93.2%) skin and soft tissue infections (SSTIs). Thirty-five patients were ≤30 days of age. The proportion of staphylococcal infections caused by a community-associated methicillin-resistant <it>Staphylococcus aureus </it>(CA-MRSA) isolate increased from 51.5% (69 of 134) in 2003-2006 to 63.4% (111 of 175) in 2007-2009 (<it>P </it>= 0.037). Among the CA-MRSA isolates, 88.9% were resistant to fusidic acid, 77.6% to tetracycline, and 21.1% to clindamycin. Clindamycin resistance increased from 0% (2003) to 31.2% (2009) among the CA-MRSA isolates (<it>P </it>= 0.011). Over the 7-year period, an increase in multidrug-resistant CA-MRSA isolates was observed (<it>P </it>= 0.004). One hundred and thirty-one (93.6%) of the 140 tested MRSA isolates were Panton-Valentine leukocidin-positive. Multilocus sequence typing of 72 CA-MRSA isolates revealed that they belonged to ST80 (n = 61), ST30 (n = 6), ST377 (n = 3), ST22 (n = 1), and ST152 (n = 1). Resistance to fusidic acid was observed in ST80 (58/61), ST30 (1/6), and ST22 (1/1) isolates.</p> <p>Conclusion</p> <p>In areas with high rate of infections caused by multidrug-resistant CA-MRSA isolates, predominantly belonging to the European ST80 clone, fusidic acid and clindamycin should be used cautiously as empiric therapy in patients with suspected severe staphylococcal infections.</p

Low-Temperature Polymorphic Phase Transition in a Crystalline Tripeptide L-Ala-L-Pro-Gly·H2O Revealed by Adiabatic Calorimetry

We demonstrate application of precise adiabatic vacuum calorimetry to observation of phase transition in the tripeptide l-alanyl-l-prolyl-glycine monohydrate (APG) from 6 to 320 K and report the standard thermodynamic properties of the tripeptide in the entire range. Thus, the heat capacity of APG was measured by adiabatic vacuum calorimetry in the above temperature range. The tripeptide exhibits a reversible first-order solid-to-solid phase transition characterized by strong thermal hysteresis. We report the standard thermodynamic characteristics of this transition and show that differential scanning calorimetry can reliably characterize the observed phase transition with <5 mg of the sample. Additionally, the standard entropy of formation from the elemental substances and the standard entropy of hypothetical reaction of synthesis from the amino acids at 298.15 K were calculated for the studied tripeptide.National Institute of Biomedical Imaging and Bioengineering (U.S.) (EB-003151)National Institute of Biomedical Imaging and Bioengineering (U.S.) (EB-001960)National Institute of Biomedical Imaging and Bioengineering (U.S.) (EB-002026

Développement d'une méthode de dosage d'un pesticide, le folpel, et de ses produits de dégradation dans les liquides biologiques (application toxicocinétique chez le rat)

BORDEAUX2-BU Santé (330632101) / SudocSudocFranceF

Rôle du phénotype hypermutateur chez Staphylococcus aureus dans l'adaptation et la résistance aux antibiotiques dans un modéle d'osteite du rat

CAEN-BU Médecine pharmacie (141182102) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Traité pratique de viticulture : reconstitution des vignobles ; porte-greffes ; greffages ; culture et maladies de la vigne ; description des cépages français de cuve et de table / par Joseph Daurel,.... - 2e édition

Annexes : Notes bibliographiques. Inde

Représentations condensées d'ensembles de règles d'association

Ces dernières années, l'utilisation de plus en plus massive des systèmes d'information a donné lieu à l'accroissement important du nombre de bases de données et à l'augmentation de leur taille. Leurs propriétaires ont ressenti de plus en plus fortement la valeur potentielle de ces bases de données. Ils ont alors commencé à essayer de valoriser ces grands volumes de données sans se limiter aux processus d'interrogation classiques, mais en tentant d'extraire des informations à forte valeur ajoutée pouvant aboutir à l'amélioration du niveau de connaissance des utilisateurs de ces bases. De ce problème est né une discipline : l'extraction de motifs fréquents. Beaucoup d algorithmes de plus en plus performants furent développés pour ce type d extractions entre 1994 et aujourd hui. Il est maintenant souvent possible d extraire de manière quasi exhaustive certains types de motifs fréquents contenus dans une base de données. L'inconvénient majeur rencontré est le suivant : les motifs trouvés sont trop nombreux. Il est difficile de les trier par ordre d'intérêt afin d'en tirer une information intéressante. Dans ce contexte, il nous a semblé particulièrement intéressant de trouver des représentations plus condensées de motifs extraits de manière à assurer une meilleur lecture de ces résultats. Plus précisément, nous avons travaillé sur les motifs appelés règles d'association et nous avons proposé deux représentations synthétiques de jeux de règles d'association. Nous avons conçu et implanté deux algorithmes pour calculer chacune de ces représentations, et nous avons montré leur efficacité en pratique. Enfin nous avons utilisé ces représentations avec des cas réels.Recently, the more and more intense usage of information systems yielded to the growth of the number and the size of the involved databases. The owners felt more and more the potential value of those databases. They started trying to these databases to advantage without being restricted to classical querying processes, but by attempting to extract information enclosing high added value, which could lead to the improvement of the users knowledge. This issue led to the creation of a new discipline : frequent pattern extraction. A lot more and more efficient algorithms were developed to address this kind of extraction since 1994. It is now often possible to extract in an exhaustive way in most of the cases certain types of frequent patterns enclosed in a database. The major drawback that met is the following : the discovered patterns are often too numerous. It is therefor difficult to sort them following an interest order in order to derive interesting information. In this context, it appeared that it is particularly interesting to find out more condensed representations of the extracted patterns in order to ensure a better reading of the results. More precisely, we have worked on the patterns called association rules, and we have proposed two global representations of association rules sets. We have designed and implemented tow algorithms for calculating each one of these representations, and we have shown their efficiency and effectiveness in practice. At last, we have conducted tests on real-life datasets.VILLEURBANNE-DOC'INSA LYON (692662301) / SudocSudocFranceF