An experimental study was made of single fibers rotating and bending in Couette flow of a Newtonian liquid. A previous result for critical fib,er buckling was retested and found satisfactory, and the traqsition between 'springy' and 'snake' rotation was delineated. The minimum radius of curvature achieved during rotation in the "snake orbit" regime was measured as a function of fiber aspect ratio, Young's modulus, and fluid shear stress. Two correlations are presented which are constrained to satisfy limiting conditions for very stiff and very flexible fibers. Together with a result from thin rod theory, these correlations may be used to predict breaking conditions Cor fibers of known Young's modulus and ultimate tensile strength. Predictions are tested in experiments where two types of glass fiber are broken in suspension and found satisfactory. Results show that several reinforcing materials will probably break within the range of conditions covered by our experiments, or in a region which can be treated by extrapolation from our results. (3 tan + = r, tan Kr, tan 8 = (r: cos' + + sin2 +)& (3)

Canine chronic inflammatory enteropathy (CIE) is one of the most common chronic gastrointestinal diseases affecting dogs worldwide. Genetic and environmental factors, as well as intestinal microbiota and dysregulated host immune responses, participate in this multifactorial disease. Despite advances explaining the immunological and molecular mechanisms involved in CIE development, the exact pathogenesis is still unknown. This review compiles the latest reports and advances that describe the main molecular and cellular mechanisms of both the innate and adaptive immune responses involved in canine CIE pathogenesis. Future studies should focus research on the characterization of the immunopathogenesis of canine CIE in order to advance the establishment of biomarkers and molecular targets of diagnostic, prognostic, or therapeutic utility.

This study presents the development and characterization of PVDF‐conjugated polymer nanofiber‐based systems. Five different conducting polymers (CPs) were synthesized successfully and used to create the nanofiber systems. The CPs used are polyaniline (PANI), polypyrrole (PPY), polyindole (PIN), polyanthranilic acid (PANA), and polycarbazole (PCZ). Nanofiber systems were produced utilizing the Forcespinning® technique. The nanofiber systems were developed by mechanical stretching. No electrical field or post‐process poling was used in the nanofiber systems. The morphology, structure, electrochemical and piezoelectric performance was characterized. All of the nanofiber PVDF/CP systems displayed higher piezoelectric performance than the fine fiber PVDF systems. The PVDF/PPY nanofiber system displays the highest piezoelectric performance of 15.56 V. The piezoelectric performance of the PVDF/CP nanofiber systems favors potential for an attractive source of energy where highly flexible membranes could be used in power actuators, sensors and portable, and wireless devices to mention some.

Most of the conjugated polymer employed as fluorescent biosensors present low solubility and emission in aqueous environment. In order to solve this feature, we have reconstituted, in buffer phosphate, a neutral conjugated poly[9,9-bis(6'-bromohexil)-2,7-fluorene-co-alt-1,4-phenylene], as PFPBr 2 (insoluble in water), in the presence of an artificial zwitterionic phospholipids bilayers, as 1,2-dimyristoyl-sn-glycero-3-phospho-choline (DMPC). Quantum yield of PFPBr 2 -DMPC was around 20% in phosphate buffer, it was identical value calculated from ammonium polyelectrolytes (PFPNMe 3+ ). In addition, the maximum of bluish emission for buffer solution of PFPBr 2 -DMPC was at 420nm, a redshift emission with regard to chloroform solution (at 410 nm). The structural study at different concentrations of PFPBr 2 and DMPC was carried out using different approaches: steady state fluorescence spectroscopy, confocal fluorescence microscopy and calorimetry. A positive interaction takes place involving neutral conjugated polymer and zwitterionic phospholipids bilayer. Novels complexes or associations of poly(fluorene-phenylene) (PFPBr 2 ) and zwitterionic phospholipids (DMPC) have been suggested and visualized by epifluorescence. Phase transitions of the liposomes have been also detected by differential scanning calorimetry.