340 research outputs found

    Composición Arquitectónica 5 y 6

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    La presente Memoria culmina el trabajo colaborativo del área de conocimiento de Composición Arquitectónica por lo que respecta a las materias de Grado en (Fundamentos en) Arquitectura, al haber definido sus contenidos, sus métodos de aprendizaje y sus sistemas de evaluación para el conjunto de la titulación. Ahora se concretan las dos últimas asignaturas de 5º curso: CA5 y CA6. Por un lado está CA5, cuyo eje fundamental es la definición de criterios para el ejercicio de la crítica de arquitectura, una vez que se ha construido una base de información histórica y teórica en los estudiantes a lo largo de cuatro cursos. Una crítica entendida tanto como sistema de contextualización sobre las obras ejecutadas (del presente o del pasado) y, a la vez, como marco de referencia para someter a evaluación las soluciones que se proponen desde proyecto (desde el presente hacia el futuro). Así pues, crítica entendida como herramienta de análisis tanto como de prospección. Por otro lado está CA6, en la que el eje fundamental es la intervención sobre el patrimonio arquitectónico, sea o no monumental, entendido como una realidad ineludible pues gran parte del trabajo de los arquitectos transita sobre preexistencias en sus muy diversos grados

    Niveles De Motivación Y Las Competencias Laborales Específicas De Los Trabajadores A Distancia

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    The aim of this study was to determine the relationship between motivation and specific job skills of teleworkers. The methodology was applied, descriptive and correlational. The study was hypothetical deductive, non experimental, transactional and quantitative. The sampling was non probabilistic by quotas, was included telecommuters from different companies that use this type of work, located in the interior of Mexico, USA and Canada. The sample size was 27 teleworkers. A questionnaire of 52 questions was used as a measuring tool. The data analysis was descriptive and chi square test was used to identify the relationship of the independent variable motivation with the dependent variable specific job skills of teleworkers. The main results showed that motivation is high and teleworkers have a high development in most of their job skills. Also among the most outstanding results it was found that the variable motivation in the three indicators analyzed: the need for existence, value and growth, have a closer relationship with labor competition autonomy, than the rest of labor skills analyzed

    Removal of bacteria from boar semen using a low-density colloid

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    P. 272-278Antibiotics are added to semen extenders when preparing commercial semen doses for artificial insemination according to national and international guidelines. However, this addition of antibiotics represents non-therapeutic usage and could be contributing to the development of antibiotic resistance. Colloid centrifugation was shown to reduce the load of bacteria present in boar semen and was capable of removing all bacteria if performed directly after semen collection, albeit with some loss of spermatozoa. The present experiment was conducted with a low density colloid to investigate whether it was possible to separate all of the spermatozoa from seminal plasma i.e. without selection for robust spermatozoa, or whether this would have a detrimental effect on sperm quality. Ejaculates from nine boars were extended in Beltsville Thawing Solution without antibiotics and were transported to the laboratory for Single Layer Centrifugation (SLC) on modified Porcicoll i.e. at a low density (S). A further modification was that a sterile inner tube was included inside some of the 50 mL centrifuge tubes to facilitate harvesting of the sperm pellet (M). Aliquots of all samples (control, S and M) were cultured for bacterial quantification and identification using standard microbiological methods. Sperm quality was evaluated daily. Three of the C and M samples and five of the S samples did not contain any bacteria. Mean bacterial counts for the remaining samples (colony forming units/mL) were as follows: C 259 ± 216; S 30 ± 22; M 33 ± 15 (P < 0.01). Citrobacter spp., Staphylococcus simulans, Klebsiella variicola, Escherichia coli, Myroides odoratimimus, Proteus spp. and Enterococcus faecalis were identified in the control samples. There were marginal differences in sperm quality among treatments, with sperm velocity and linearity being higher in S and M samples than in C at all time points. However, sperm viability, capacitation and acrosome status were marginally better in controls than in S or M on day 0, but these differences disappeared during storage. Conclusions: centrifugation through a low density colloid can remove or reduce bacterial contamination in boar ejaculates without using antibiotics. Furthermore, it is possible to collect boar ejaculates without bacterial contamination by paying strict attention to hygiene.S

    Vasoactive Intestinal Peptide maintains the non-pathogenic profile of human Th17-polarized cells

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    The cytokine microenvironment modulates CD4 T cell differentiation causing the shift of naïve CD4 T cells into different cell subsets. This process is also regulated by modulators such as VIP, a neuropeptide with known immunomodulatory properties on CD4 T cells that exert this action through specific receptors, VPAC1 and VPAC2. Our results show that the pattern of VIP receptors expression ratio is modified during Th17 differentiation. In this report, we evaluate the capacity of VIP to modulate naïve human cells into Th17 cells in vitro by analyzing their functional phenotype. The presence of VIP maintains the non-pathogenic profile of Th17-polarized cells, increases the proliferation rate and decreases their Th1 potential. VIP induces the up-regulation of the STAT3 gene interaction with the VPAC1 receptor during the onset of Th17 differentiation. Moreover, RORC, RORA and IL-17A genes are up-regulated in the presence of VIP through interaction with VPAC1 and VPAC2 receptors. Interestingly, VIP induces the expression of the IL-23R gene through interaction with the VPAC2 receptor during the expansion phase. This is the first report that describes the differentiation of naïve human T cells to Th17-polarized cells in the presence of VIP and demonstrates how this differentiation regulates the expression of the VIP receptors

    Production of drug-releasing biodegradable microporous scaffold impregnated with gemcitabine using a CO2 foaming process

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    The use of supercritical fluids technology, in particular the use of CO2, is an important advantage over other production techniques of controlled release systems. The impregnation and foaming process can be carried out in a single step. By adjusting the conditions of pressure, temperature, depressurization time or type of polymer used, microcellular scaffolds can be obtained with desired characteristics and adapted to the patient's requirements. Moreover, it has been demonstrated that the use of polymeric solutions allows carrying out impregnation process at mild conditions. In this work, Gemcitabine impregnation in PLGA foams from polymeric solutions of ethyl lactate has been studied. The effect of polymer lactide to glycolide ratio (50:50 or 75:25), pressure (120 or 200 bar) and temperature (25 or 40 °C) were studied for three initial drug ratios (175, 105 or 35 mg GEM/g PLGA). Cell size of the foams varied between 35 μm and 158 μm, achieving an impregnation efficiency higher than 90 %. Finally, a study of the release profile of Gemcitabine in Phosphate Buffered Saline (PBS) was investigated and a mathematical modelling was carried out. In this model it was considered that the release process was divided into three different steps controlled by the external diffusion in the first place, by the internal transfer of mass in the second and then by the degradation of the polymer.El uso de la tecnología de fluidos supercríticos, en particular el uso de CO2, es una importante ventaja frente a otras técnicas de producción de sistemas de liberación controlada. El proceso de impregnación y espumado se puede realizar en un solo paso. Ajustando las condiciones de presión, temperatura, tiempo de despresurización o tipo de polímero utilizado, se pueden obtener andamios microcelulares con las características deseadas y adaptados a los requerimientos del paciente. Además, se ha demostrado que el uso de soluciones poliméricas permite llevar a cabo el proceso de impregnación en condiciones suaves. En este trabajo se ha estudiado la impregnación de gemcitabina en espumas de PLGA a partir de soluciones poliméricas de lactato de etilo. El efecto de la relación entre la lactida y el glicólido del polímero (50:50 o 75:25), Se estudiaron la presión (120 o 200 bar) y la temperatura (25 o 40 °C) para tres proporciones iniciales de fármaco (175, 105 o 35 mg GEM/g PLGA). El tamaño de celda de las espumas varió entre 35 μm y 158 μm, logrando una eficiencia de impregnación superior al 90 %. Finalmente, se investigó un estudio del perfil de liberación de gemcitabina en solución salina tamponada con fosfato (PBS) y se llevó a cabo un modelo matemático. En este modelo se consideró que el proceso de liberación se dividía en tres pasos diferentes controlados por la difusión externa en primer lugar, por la transferencia interna de masa en el segundo y luego por la degradación del polímero. Se investigó un estudio del perfil de liberación de gemcitabina en solución salina tamponada con fosfato (PBS) y se llevó a cabo un modelo matemático. En este modelo se consideró que el proceso de liberación se dividía en tres pasos diferentes controlados por la difusión externa en primer lugar, por la transferencia interna de masa en el segundo y luego por la degradación del polímero. Se investigó un estudio del perfil de liberación de gemcitabina en solución salina tamponada con fosfato (PBS) y se llevó a cabo un modelo matemático. En este modelo se consideró que el proceso de liberación se dividía en tres pasos diferentes controlados por la difusión externa en primer lugar, por la transferencia interna de masa en el segundo y luego por la degradación del polímero

    Production of biodegradable PLGA foams processed with high pressure CO2

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    Microcellular scaffolds were prepared using high pressure fluids. Solutions of biodegradable material Poly (lactic-co-glycolic) acid (PLGA) in a green solvent such as ethyl lactate was used as the scaffold matrix. To carry out polymer foaming from polymer solutions allows the possibility of reducing the working temperature. The effect of the ratio lactide to glycolide of the polymer, the working pressure, the initial concentration of the polymer in the solvent and the depressurization time were the variables studied at a temperature of 25 °C. The morphology of the foams obtained was characterized based on the cell diameter and its standard deviation, indicator of the homogeneity of the scaffolds obtained, as well as the density of cells. In addition, a study was performed on how the glass transition temperature (Tg) of a polymer is modified by the plasticizing effect of CO2 pressure.Los andamios microcelulares se prepararon utilizando fluidos a alta presión. Como matriz de andamiaje se utilizaron soluciones de material biodegradable ácido poli (láctico-co-glicólico) (PLGA) en un disolvente verde como el lactato de etilo. Llevar a cabo la espumación de polímeros a partir de soluciones de polímeros permite la posibilidad de reducir la temperatura de trabajo. El efecto de la relación láctido a glicólido del polímero, la presión de trabajo, la concentración inicial del polímero en el solvente y el tiempo de despresurización fueron las variables estudiadas a una temperatura de 25 °C. La morfología de las espumas obtenidas se caracterizó en base al diámetro de celda y su desviación estándar, indicador de la homogeneidad de los andamios obtenidos, así como la densidad de celdas. Además,2 presiones

    Measurement, correlation and modelling of high-pressure phase equilibrium of PLGA solutions in CO2

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    Poly (lactic-co-glycolic acid) (PLGA) is a copolymer used as drug carrier in controlled release systems as microparticles or scaffolds. Foamed structures are industrially obtained by injecting gas at temperatures above the melting point of the polymer that may promote PLGA degradation. High temperatures are avoidable in this foaming process if a polymer dissolution is used. Ethyl acetate and ethyl lactate are suitable solvents for the PLGA since the polymer is easily solubilised, is environmentally friendly and highly recommendable for medical purposes. CO2 is proposed as antisolvent because is environmentally benign, non-flammable and non-toxic. The knowledge of the solubility of these solvents in CO2 is essential to find the most appropriate working conditions for the foaming process. In this work, the solubility of ethyl acetate and ethyl lactate in CO2 in the presence of different initial concentrations of PLGA has been studied at 298.15 K and at pressures up to 150 bar using a high-pressure variable volume view cell.El poli (ácido láctico-co-glicólico) (PLGA) es un copolímero que se utiliza como transportador de fármacos en sistemas de liberación controlada como micropartículas o andamios. Las estructuras espumadas se obtienen industrialmente mediante la inyección de gas a temperaturas superiores al punto de fusión del polímero que pueden promover la degradación del PLGA. Las altas temperaturas se pueden evitar en este proceso de formación de espuma si se utiliza una disolución de polímero. El acetato de etilo y el lactato de etilo son disolventes adecuados para el PLGA ya que el polímero se solubiliza fácilmente, es respetuoso con el medio ambiente y muy recomendable para fines médicos. El CO2 se propone como antidisolvente porque es ambientalmente benigno, no inflamable y no tóxico. El conocimiento de la solubilidad de estos disolventes en CO 2es fundamental encontrar las condiciones de trabajo más adecuadas para el proceso de espumado. En este trabajo se ha estudiado la solubilidad del acetato de etilo y lactato de etilo en CO 2 en presencia de diferentes concentraciones iniciales de PLGA a 298,15 K y presiones de hasta 150 bar utilizando una celda de visión de volumen variable de alta presión

    Ten-year course of treated bipolar I disorder: The role of polarity at onset

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    Introduction: Early-stage predictors of illness course are needed in bipolar disorder (BD). Differences among patients with a first depressive versus maniac/hypomanic episode have been stated, although in most studies, memory bias and time from onset to start of specialized treatment might interfere. The aim was to compare the first 10 years of illness course according to polarity at onset. Methods: 49 type I BD patients admitted for treatment for a first-time affective episode and a following 10-year attendance to the institution were included. A retrospective year by year comparison according to polarity at onset (depressive (DPO) or maniac (MPO)) was performed. Cramer's V and Cohen d were computed to determine effect size. Results: 59.2% (n = 29) started with MPO. Both groups were similar in demographic and social outcome characteristics, clinical features, and treatment variables. Patients with DPO reported more depressive episodes than MPO patients (U = 149.0 p < .001, Cohen's d = 0.87); both groups had a similar number of manic episodes. Only during the first year of follow-up, suicide attempts (SA) were more frequent in patients with DPO while the presence of a psychotic episode and psychiatric hospitalizations were more frequent in the MPO group. Conclusion: According to these findings, it can be concluded that illness onset is only indicative of depressive predominant polarity but is not related to other poor prognostic variables after the first year of illness onset, in treated BD. SA in the first year of an affective disorder could represent a marker of BD

    Association of thymidylate synthase polymorphisms with acute pancreatitis and/or peripheral neuropathy in HIV-infected patients on Stavudine-Based Therapy

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    BACKGROUND: Low expression thymidylate synthase (TS) polymorphism has been associated with increased stavudine triphosphate intracellular (d4T-TP) levels and the lipodystrophy syndrome. The use of d4T has been associated with acute pancreatitis and peripheral neuropathy. However, no relationship has ever been proved between TS polymorphisms and pancreatitis and/or peripheral neuropathy. METHODS: We performed a case-control study to assess the relationship of TS and methylene-tetrahydrofolate reductase (MTHFR) gene polymorphisms with acute pancreatitis and/or peripheral neuropathy in patients exposed to d4T. Student's t test, Pearson's correlations, one-way ANOVA with Bonferroni correction and stepwise logistic regression analyses were done. RESULTS: Forty-three cases and 129 controls were studied. Eight patients (18.6%) had acute pancreatitis, and 35 (81.4%) had peripheral neuropathy. Prior AIDS was more frequent in cases than in controls (OR = 2.36; 95%CI 1.10-5.07, P = 0.0247). L7ow expression TS and MTHFR genotype associated with increased activity were more frequent in patients with acute pancreatitis and/or peripheral neuropathy than in controls (72.1% vs. 46.5%, OR = 2.97; 95%CI: 1.33-6.90, P = 0.0062, and 79.1% vs. 56.6%, OR = 2.90, 95%CI: 1.23-7.41, P = 0.0142, respectively). Independent positive or negative predictors for the development of d4T-associated pancreatitis and/or peripheral neuropathy were: combined TS and MTHFR genotypes (reference: A+A; P = 0.002; ORA+B = 0.34 [95%CI: 0.08 to 1.44], ORB+A = 3.38 [95%CI: 1.33 to 8.57], ORB+B = 1.13 [95%CI: 0.34 to 3.71]), nadir CD4 cell count >200 cells/mm(3) (OR = 0.38; 95%CI: 0.17-0.86, P = 0.021), and HALS (OR = 0.39 95%CI: 0.18-0.85, P = 0.018). CONCLUSIONS: Low expression TS plus a MTHFR genotype associated with increased activity is associated with the development of peripheral neuropathy in d4T-exposed patients
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