Characterization of Fabric-to-Fabric Friction: Application to Medical Compression Bandages

Fabric-to-fabric friction is involved in the action mechanism of medical compression devices such as compression bandages or lumbar belts. To better understand the action of such devices, it is essential to characterize, in their use conditions (mainly pressure and stretch), the frictional properties of the fabrics they are composed of. A characterization method of fabric-to-fabric friction was developed. This method was based on the customization of the fourth instrument of the Kawabata Evaluation System, initially designed for fabric roughness and friction characterization. A friction contactor was developed so that the stretch of the fabric and the applied load can vary to replicate the use conditions. This methodology was implemented to measure the friction coefficient of several medical compression bandages. In the ranges of pressure and bandage stretch investigated in the study, bandage-to-bandage friction coefficient showed very little variation. This simple and reliable method, which was tested for commercially available medical compression bandages, could be used for other medical compression fabrics

Engineering access to higher education through higher education fairs

Text from van Zanten A., Legavre A. “Engineering access to higher education through higher education fairs”, in Goastellec G., Picard F. (ed.) The Roles of Higher Education and Research in the Fabric of Societies, Leuven, Sense Publishers, 2014 (in press). Transition to higher education is a major social process. This transition has been mostly studied by French sociologists of education and higher education from perspectives focusing predominantly on the role of the socio-economic status, academic profiles and different tracks followed by secondary school students (Merle 1996, Duru-Bellat and Kieffer 2008, Convert 2010), and, to a lesser extent, on the types of secondary schools attended (Duru-Bellat and Mingat 1998, Nakhili 2005) and the local higher education provision (Berthet et al. 2010, Orange 2013). Although these structural determinants play a major role in explaining significant regularities, they provide more powerful explanations for individuals representing the extremes of the different variables considered, leaving room for the influence of other major factors for those students in intermediate situations. In addition, even in the case of students occupying extreme positions, structural perspectives better explain the distribution of students between different higher education tracks than they do between institutions and disciplines. In this chapter, we adopt a perspective that we see as complementary to and interacting with the perspective centred on structural determinants by focusing on the role of the devices that mediate the exchanges between students and higher education institutions, and more specifically on one device: higher education fairs. Our purpose in doing so is not only to document how these various devices frame, in ways that remain largely unexplored by researchers, exchanges between providers and consumers of higher education but also to point out – and further explore in future publications – how these devices, and the specific features of fairs, contribute to the reproduction and transformation of educational inequalities in access to higher education (Benninghoff et al. 2012)

Structure and inhibitory effects on angiogenesis and tumor development of a new vascular endothelial growth inhibitor

Blocking angiogenesis is an attractive strategy to inhibit tumor growth, invasion, and metastasis. We describe here the structure and the biological action of a new cyclic peptide derived from vascular endothelial growth factor (VEGF). This 17-amino acid molecule designated cyclopeptidic vascular endothelial growth inhibitor (cyclo-VEGI, CBO-P11) encompasses residues 79-93 of VEGF which are involved in the interaction with VEGF receptor-2. In aqueous solution, cyclo-VEGI presents a propensity to adopt a helix conformation that was largely unexpected because only \u3b2-sheet structures or random coil conformations have been observed for macrocyclic peptides. Cyclo-VEGI inhibits binding of iodinated VEGF165 to endothelial cells, endothelial cells proliferation, migration, and signaling induced by VEGF165. This peptide also exhibits anti-angiogenic activity in vivo on the differentiated chicken chorioallantoic membrane. Furthermore, cyclo-VEGI significantly blocks the growth of established intracranial glioma in nude and syngeneic mice and improves survival without side effects. Taken together, these results suggest that cyclo-VEGI is an attractive candidate for the development of novel angiogenesis inhibitor molecules useful for the treatment of cancer and other angiogenesis-related diseases

The Physics of the B Factories

This work is on the Physics of the B Factories. Part A of this book contains a brief description of the SLAC and KEK B Factories as well as their detectors, BaBar and Belle, and data taking related issues. Part B discusses tools and methods used by the experiments in order to obtain results. The results themselves can be found in Part C

The crystal structure of a high affinity RNA stem-loop complexed with the bacteriophage MS2 capsid: Further challenges in the modeling of ligand-RNA interactions.

We have determined the structure to 2.8 Å of an RNA aptamer (F5), containing 2′-deoxy-2-aminopurine (2AP) at the −10 position, complexed with MS2 coat protein by soaking the RNA into precrystallised MS2 capsids. The −10 position of the RNA is an important determinant of binding affinity for coat protein. Adenine at this position in other RNA stem-loops makes three hydrogen bonds to protein functional groups. Substituting 2AP for the −10 adenine in the F5 aptamer yields an RNA with the highest yet reported affinity for coat protein. The refined X-ray structure shows that the 2AP base makes an additional hydrogen bond to the protein compared to adenine that is presumably the principal origin of the increased affinity. There are also slight changes in phosphate backbone positions compared to unmodified F5 that probably also contribute to affinity. Such phosphate movements are common in structures of RNAs bound to the MS2 T = 3 protein shell and highlight problems for de novo design of RNA binding ligands

Biomaterial granules used for filling bone defects constitute 3D scaffolds: porosity, microarchitecture and molecular composition analyzed by microCT and Raman microspectroscopy

Biomaterials are used in the granular form to fill small bone defects. Granules can be prepared with a grinder from trabecular bone samples or provided as synthetic biomaterials by industry. Granules occupy the 3D-space and create a macroporosity allowing invasion of vascular and bone cells when the inter-granular pores are larger than 300 µm. We compared the 3D-porosity of granule stacks obtained or prepared with nine biomaterials Osteopure , Lubboc , Bio-Oss , CopiOs , TCP Dental , TCP Dental HP , KeraOs , and TCH in comparison with that of human trabecular bone. For each biomaterial, two sizes of granules were analyzed: 250-1000 and 1000-2000 µm. Microcomputed tomography determined porosity and microarchitectural characteristics of granular stacks and Raman microspectroscopy was used to analyze their composition. Stacks of 250-1000 µm granules had a much lower porosity than 1000-2000 µm granules and the maximum frequency of pores was always centered at 200-250 µm. One biomaterial contained substantial amount of cortical bone (Bio-Oss ). The highest porosity and pore size was obtained with TCP Dental HP. Raman spectroscopy found differences in biomaterials of the same composition. Stacks of granules represent 3D scaffolds resembling trabecular bone with an interconnected porous microarchitecture. Small granules have created pores <300 µm in diameter; this can interfere with vascular colonization. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2018