On the correlation between residual stresses and displacements of the polycrystalline lattice: an experimental strategy

This work aims to propose a micro-indent method to evaluate the correlation between the relaxation of residual stresses and the shape changes of the polycrystalline lattice in specimens of a rolled plate of AA 6082-T6 aluminium alloy. Rolling strengthens the surface of the plate by introducing compressive residual stresses. Then, these stresses are relaxed by thermal distension. The method of micro-indents allowed measuring residual displacements with an error below ± 300 nm. The results obtained reveal that the rolling direction plays a vital role in terms of asymmetric expansion of the lattice. Furthermore, the lattice accumulates and restores elastic strain energy in the clockwise and anti-clockwise direction of rotation, alternatively. Finally, when the stress release process is finishing, the lattice adjusts the angle of rotation to approximate to the initial geometric shape.Fil: Diaz, Felipe Victor. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Tecnológica Nacional. Facultad Regional Rafaela; ArgentinaFil: Rosso, F. N.. Universidad Tecnológica Nacional. Facultad Regional Rafaela; ArgentinaFil: Walker, A. C.. Universidad Tecnológica Nacional. Facultad Regional Rafaela; ArgentinaFil: Guidobono, A.P.M.. Instituto Nacional de Tecnología Industrial. Centro Regional Rosario; Argentin

An immunohistochemical study of the antinociceptive effect of calcitonin in ovariectomized rats

<p>Abstract</p> <p>Background</p> <p>Calcitonin is used as a treatment to reduce the blood calcium concentration in hypercalcemia and to improve bone mass in osteoporosis. An analgesic effect of calcitonin has been observed and reported in clinical situations. Ovariectomaized (OVX) rats exhibit the same hormonal changes as observed in humans with osteoporosis and are an animal model of postmenopousal osteoporosis. The aim of this study to investigate antinociceptive effect of calcitonin in OVX rats using the immunohistochemical study.</p> <p>Methods</p> <p>We assessed the antinociceptive effects of calcitonin in an ovariectomized (OVX) rat model, which exhibit osteoporosis and hyperalgesia, using the immunohistochemical method. Fifteen rats were ovariectomized bilaterally, and ten rats were received the same surgery expected for ovariectomy as a sham model. We used five groups: the OVX-CT (n = 5), the sham-CT (n = 5), and the OVX-CT-pcpa (n = 5) groups recieved calcitonin (CT: 4 U/kg/day), while OVX-vehi (n = 5) and the sham-vehi (n = 5) groups received vehicle subcutaneously 5 times a week for 4 weeks. The OVX-CT-pcpa-group was given traperitoneal injection of p-chlorophenylalanine (pcpa; an inhibitor of serotonin biosynthesis) (100 mg/kg/day) in the last 3 days of calcitonon injection. Two hours after 5% formalin (0.05 ml) subcutaneously into the hind paw, the L5 spinal cord were removed and the number of Fos-immunoreactive (ir) neurons were evaluated using the Mann-Whitney-U test.</p> <p>Results</p> <p>The numbers of Fos-ir neurons in the OVX-CT and sham-CT groups were significantly less than in the OVX-vehi and sham-vehi groups, respectively (p = 0.0090, p = 0.0090). The number of Fos-ir neurons in the OVX-CT-pcpa-group was significantly more than that of the OVX-CT-group (p = 0.0283), which means pcpa inhibits calcitonin induced reduction of c-Fos production.</p> <p>Conclusion</p> <p>The results in this study demonstrated that 1) the increase of c-Fos might be related to hyperalgesia in OVX-rats. 2) Calcitonin has an antinociceptive effect in both OVX and sham rats. 3) The central serotonergic system is involved in the antinociceptive properties of calcitonin.</p

Sustentabilidad y territorio. Herramientas para la gestión sustentable del hábitat

Con más de 7,500 millones de habitantes en el mundo, construir hábitats sustentables es un reto complejo. La proliferación de grandes y desordenadas concentraciones urbanas genera un deterioro en la calidad de vida, desigualdad y pobreza, así como la transformación y pérdida irreparable de ecosistemas, por lo que se vuelve urgente el actuar para paliar y revertir este fenómeno. Este libro recoge una selección de trabajos de investigación que se presentaron en el Congreso Internacional sobre Sustentabilidad en los Hábitats, realizado en 2016. Son seis propuestas elaboradas por alumnos de posgrado, profesores y académicos de diversos países, en las que se abordan desde una perspectiva internacional y local, los retos a enfrentar en el camino hacia la sustentabilidad, en aspectos como el deterioro físico y social de los espacios de vida en la ciudad, la atracción y retención de capital humano, movilidad y reorganización urbana, contaminación, defensa del territorio, del patrimonio cultural y natural e inseguridad por eventos contingentes, entre otros. Ante un mundo (in)sustentable, los autores presentan alternativas para desarrollar lugares sustentables para la vida. Un libro que convoca a estudiantes, profesores e investigadores a una búsqueda colectiva para la construcción de un mundo mejor

Amylin and gastrointestinal activity

1. Amylin is a new pancreatic islet peptide with a role in the maintenance of glucose homeostasis. 2. Amylin is predominantly present in the beta cells of the pancreas and to a lesser extent in the gastrointestinal tract and in the nervous system, where amylin mRNA is also present along with specific binding sites. 3. Amylin given peripherally or centrally inhibits acid gastric secretion in a dose-dependent manner and has a protective effect against indomethacin- or ethanol-induced ulcers only when injected centrally. 4. Subcutaneous or central injection of amylin produces a dose-dependent inhibition of gastric emptying, which may contribute to the activity of amylin in the regulation of carbohydrate absorption. In addition amylin inhibits food intake both when injected peripherally or centrally. 5. Amylin may thus be considered a novel brain-gut peptide taking part in the rapid endocrine response during digestion to maintain euglycemia

CRYOPRESERVATION OF POULTRY SEMEN - A REVIEW

Although still in the experimental phase, the technique of freezing domestic fowl semen may prove of interest and value to the industry. Various stages of the application of this method of preservation still need to be improved. One of the most critical aspects is the choice of cryoprotectant and its use during the process of freezing and thawing. While glycerol has a better cryopreservative action than other cryoprotectants in domestic fowl semen, it exerts a widely demonstrated contraceptive action, the mechanism of which has not yet been clarified. Thus the use of glycerol as a cryoprotectant must be accompanied by its complete removal before insemination. The fertilizing capacity of semen preserved by freezing is notably less than that of fresh (non-preserved) material and has been evaluated as 1.6% and 19.7%. Genetic influences appear to affect spermatozoan response and tolerance to thermal treatments resulting in differences in subsequent fertility. Most studies using fowl semen report final freezing temperatures between -79-degrees-C and -196-degrees-C, a cooling rate of 1-10-degrees-C/minute and a thawing rate of 50-70-degrees-C/minute. Straws have been found to be more satisfactory containers than glass vials or ampoules for preserving semen from domestic fowl