Failure analysis of Co–Cr hip resurfacing prosthesis during solidification

In this study a failure originated during solidification process into the femoral stem component of Hip Resurfacing prosthesis was investigated. Visual inspection, optical microscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and a commercial software simulation ProCAST were carried out in order to determine the cause and solution of this failure. The results exhibited hot tearing, shrinkage porosity and metal oxide films due to inadequate heat dissipation during solidification process, as a consequence of poor investment casting ceramic mold configuration. Also in this paper was improved the casting design solving this kind of defects

Beta-cell mass adaptation to ileum nutrient flow. An experimental model

The population with obesity has increased at an alarming rate during this century. Bariatric surgery has been demonstrated to be a good method to control weight and, most importantly, associated comorbidities, such as type 2 diabetes mellitus or high blood pressure. The reason why this happens even before losing significant weight remains unclear. Many authors believe that incretins play a main role, triggering special functions of the digestive tract. In reports, these hypotheses are known as foregut and hindgut theories. Initially, the theories were mutually exclusive; additionally, many other propositions have been analysed, according to different surgical techniques (e.g., bile acids and specific enterohormonal components). To elucidate the participation of the ileum, we developed a surgical technique to study the rapid response to nutrients in the ileum. Our goal was to study the stress functional test and histological changes in the pancreas that may explain the variations in glycaemic homeostasis in our rat model. After the oral glucose tolerance test, the experimental group presented an increased insulin release response with conserved glycaemia. We report an increasing beta-cell mass in the experimental group (+11.87 mg vs. +9.65 mg, respectively), while alpha-cell mass was not different. Based on transcription factors, the pathways that were increased were the proliferation process (as the number of PCNA-positive cells in the experimental group versus sham (+12.06 vs. +6.2 PCNA+ cells/mm2)) and transdifferentiation (ARX; +2.67 ARX+ cells/mm2 in the experimental group vs. +2.04 ARX+ cells/mm2 in the controls). We report the consequences of the rapid arrival of nonprocessed nutrients to the ileum on the endocrine cellular pancreas. The ileum could be a principal effector in the enterohormonal axis, which conditions endocrine pancreas cellularit

Diagnóstico acerca del proceso de seguimiento de egresados de la fime

Una forma de la vinculación entre la universidad y la industria es el proceso de seguimiento de egresados (PSE). A través de la opinión de egresados y empleadores se logra conocer el desempeño laboral de los egresados. Las exigencias sociales apuntan a explorar nuevos retos para que la universidad forme profesionales a la altura de las expectativas del mercado laboral. Es por ello que el PSE necesita enfocarse desde una perspectiva más integral explotando sus alcances formativos. El presente trabajo presenta algunos de los resultados obtenidos en la primera fase de una investigación sobre el PSE según esta nueva visión. Su objetivo fundamental es analizar las características esenciales de dicho proceso en un contexto específico; la Facultad de Ingeniería Mecánica y Eléctrica (FIME) de la Universidad Autónoma de Nuevo León (UANL). Por medio de métodos cuantitativos y cualitativos se diagnosticó la situación actual aplicando instrumentos a los actores involucrados. A través de la información recolectada se detectaron fortalezas y debilidades las que se han de tomar como referentes para el perfeccionamiento del PSE. Los resultados demuestran las potencialidades formativas del seguimiento de egresados

Banda transportadora desde el enfoque Sistema de Visión.

Esta banda transportadora es capaz de detectar en los objetos colores y formas determinados con anterioridad, esto por medio de una cámara HD dada su excelente calidad, por medio de sistemas de visión. Al momento de que los objetos pasen por esta cámara se ingresaran en la base de datos que se creó con las combinaciones requeridas de formas y colores; ya localizando el objeto la banda separara los objetos y los pondrán en el lugar donde pertenecen. Con esto se desea lograr un sistema automatizado capaz de separar u ordenar objetos dados por sus características

Unique Organization of the Nuclear Envelope in the Post-natal Quiescent Neural Stem Cells

Neural stem cells (B1 astrocytes; NSCs) in the adult ventricular-subventricular-zone (V-SVZ) originate in the embryo. Surprisingly, recent work has shown that B1 cells remain largely quiescent. They are reactivated postnatally to function as primary progenitors for neurons destined for the olfactory bulb and some corpus callosum oligodendrocytes. The cellular and molecular properties of quiescent B1 cells remain unknown. Here we found that a subpopulation of B1 cells has a unique nuclear envelope invagination specialization similar to envelope-limited chromatin sheets (ELCS), reported in certain lymphocytes and some cancer cells. Using molecular markers, [3H]thymidine birth-dating, and Ara-C, we found that B1 cells with ELCS correspond to quiescent NSCs. ELCS begin forming in embryonic radial glia cells and represent a specific nuclear compartment containing particular epigenetic modifications and telomeres. These results reveal a unique nuclear compartment in quiescent NSCs, which is useful for identifying these primary progenitors and study their gene regulation

Diagnóstico acerca del proceso de seguimiento de egresados de la FIME

Una forma de la vinculación entre la universidad y la industria es el proceso de seguimiento de egresados (PSE). A través de la opinión de egresados y empleadores se logra conocer el desempeño laboral de los egresados. Las exigencias sociales apuntan a explorar nuevos retos para que la universidad forme profesionales a la altura de las expectativas del mercado laboral. Es por ello que el PSE necesita enfocarse desde una perspectiva más integral explotando sus alcances formativos. El presente trabajo presenta algunos de los resultados obtenidos en la primera fase de una investigación sobre el PSE según esta nueva visión. Su objetivo fundamental es analizar las características esenciales de dicho proceso en un contexto específico; la Facultad de Ingeniería Mecánica y Eléctrica (FIME) de la Universidad Autónoma de Nuevo León (UANL). Por medio de métodos cuantitativos y cualitativos se diagnosticó la situación actual aplicando instrumentos a los actores involucrados. A través de la información recolectada se detectaron fortalezas y debilidades las que se han de tomar como referentes para el perfeccionamiento del PSE. Los resultados demuestran las potencialidades formativas del seguimiento de egresados

Immature excitatory neurons develop during adolescence in the human amygdala

The human amygdala grows during childhood, and its abnormal development is linked to mood disorders. The primate amygdala contains a large population of immature neurons in the paralaminar nuclei (PL), suggesting protracted development and possibly neurogenesis. Here we studied human PL development from embryonic stages to adulthood. The PL develops next to the caudal ganglionic eminence, which generates inhibitory interneurons, yet most PL neurons express excitatory markers. In children, most PL cells are immature (DCX+PSA-NCAM+), and during adolescence many transition into mature (TBR1+VGLUT2+) neurons. Immature PL neurons persist into old age, yet local progenitor proliferation sharply decreases in infants. Using single nuclei RNA sequencing, we identify the transcriptional profile of immature excitatory neurons in the human amygdala between 4–15 years. We conclude that the human PL contains excitatory neurons that remain immature for decades, a possible substrate for persistent plasticity at the interface of the hippocampus and amygdala

Do case-only designs yield consistent results across design and different databases? A case study of hip fractures and benzodiazepines.

BACKGROUND: The case-crossover (CXO) and self-controlled case series (SCCS) designs are increasingly used in pharmacoepidemiology. In both, relative risk estimates are obtained within persons, implicitly controlling for time-fixed confounding variables. OBJECTIVES: To examine the consistency of relative risk estimates of hip/femur fractures (HFF) associated with the use of benzodiazepines (BZD) across case-only designs in two databases (DBs), when a common protocol was applied. METHODS: CXO and SCCS studies were conducted in BIFAP (Spain) and CPRD (UK). Exposure to BZD was divided into non-use, current, recent and past use. For CXO, odds ratios (OR; 95%CI) of current use versus non-use/past were estimated using conditional logistic regression adjusted for co-medications (AOR). For the SCCS, conditional Poisson regression was used to estimate incidence rate ratios (IRR; 95%CI) of current use versus non/past-use, adjusted for age. To investigate possible event-exposure dependence the relative risk in the 30 days prior to first BZD exposure was also evaluated. RESULTS: In the CXO current use of BZD was associated with an increased risk of HFF in both DBs, AORBIFAP = 1.47 (1.29-1.67) and AORCPRD = 1.55 (1.41-1.70). In the SCCS, IRRs for current exposure was 0.79 (0.72-0.86) in BIFAP and 1.21 (1.13-1.30) in CPRD. However, when we considered separately the 30-day pre-exposure period, the IRR for current period was 1.43 (1.31-1.57) in BIFAP and 1.37 (1.27-1.47) in CPRD. CONCLUSIONS: CXO designs yielded consistent results across DBs, while initial SCCS analyses did not. Accounting for event-exposure dependence, estimates derived from SCCS were more consistent across DBs and designs