New materials and scaffold fabrication method for nerve tissue engineering

Acetylcholine is a neurotransmitter that regulates neurite branching, induces neurite outgrowth, and synapse formation. Because of its various roles in neuronal activities, acetylcholine-based materials may also be useful in nerve repair. We present a series of biodegradable polymers with varying concentrations of acetylcholine-like motifs. We hypothesize that neurite sprouting and extension can be enhanced by using materials to present biochemical and physical cues. Acetylcholine-like motifs were incorporated by the polycondensation of diglycidyl sebacate, aminoethyl acetate, and leucine ethyl ester, which permitted control over acetylcholine motif concentration. Interactions between the polymers and neurons were characterized using rat dorsal root ganglia explants (DRG). We screened the potential application of these materials in nerve tissue engineering using the following criteria: 1) neurite sprouting, 2) neurite length, and 3) distribution of the neurite lengths. The ability of DRG to sprout neurites was influenced by the concentration of acetylcholine motifs of the polymer. Addition of acetylcholine receptor antagonists to DRG cultured on the polymers significantly decreased neurite sprouting, suggesting acetylcholine receptors mediate sprouting on the polymers. Future studies may examine how neurons on acetylcholine-based polymers exhibit changes in downstream signaling events and cell excitability that are associated with receptor activation. In preparation for testing the acetylcholine-based polymers in vivo, porous scaffolds with longitudinally oriented channels were fabricated using fiber templating and salt leaching. Micro computed tomography, scanning electron microscopy, and cryo-sectioning revealed the presence of longitudinally oriented channels. Channel volume and average pore size of the scaffolds were controlled by the number of fibers and salt fusion time. Future studies may involve testing the effect of acetylcholine-motifs by coating polymers onto such scaffolds or assessing the effect of the scaffold's dimensional properties on nerve regeneration.Ph.D.Committee Chair: Wang, Yadong; Committee Member: Bao, Gang; Committee Member: Bellamkonda, Ravi; Committee Member: Boyan, Barbara; Committee Member: Chaikof, Elliot; Committee Member: Meredith, J. Carso

Asistencia jurídica y acceso a la justicia desde una perspectiva iberoamericana

Memoria para optar al grado de Licenciada en Ciencias Jurídicas y SocialesLa presente obra aborda la problemática del derecho fundamental de acceso a la justicia, entendido como todos los medios necesarios para acceder a la jurisdicción para la protección de los intereses de los individuos. En ella se analiza la importancia de la protección de este derecho y cuáles son las barreras que afectan a la población en su ejercicio. A su vez, se plantea a los sistemas de asistencia jurídica gratuita como uno de los mecanismos que permite garantizar el derecho de acceso a las personas más vulnerables a través del reconocimiento de la asistencia jurídica gratuita como derecho fundamental. En este sentido, se explora el sistema de asistencia jurídica en Chile desde un punto de vista procesal, evaluando el funcionamiento de las instituciones que lo componen, a saber, el abogado de turno, las Corporaciones de Asistencia Judicial, la Defensoría Penal Pública, las Oficinas de Defensa Laboral, y también de instituciones no gubernamentales coadyuvantes de las primeras, cuales son, las Clínicas Jurídicas y la Fundación Pro Bono, con el fin de identificar los problemas que enfrentan los justiciables y que merman su acceso a la justicia al momento de recurrir a estos operadores. De igual modo, se realiza un análisis comparado de los sistemas de asistencia jurídica en Argentina, Colombia, México y España, con el fin de evidenciar en su funcionamiento los aspectos positivos y negativos, y su nivel de éxito en cuanto a ofrecer una garantía efectiva del acceso a la justicia, extrapolando soluciones para las limitaciones del modelo chilen

Perceptions, Challenges and Coping Strategies of Mathematics Teachers in the Implementation of Limited Face-To-Face Classes

This study investigated how mathematics teachers at Ozamiz City School of Arts and Trades perceived the implementation of limited face-to-face classes. The researcher purposively identified ten (10) secondary mathematics teachers, parents, and students who have participated in the implementation of limited face-to-face classes. A semi-structured interview was utilized to interview the Mathematics teachers, parents, and students at OCSAT. All online and offline interviews were recorded and verified because the researcher sought to capture the data precisely and comprehensively. Using Merriam Case Study Model, particularly a three-component triangulation, the outcome is supported by the feedback from parents and students to have an authenticity of results from the main respondents. This model helps identify the perceptions, challenges encountered, coping strategies, and suggestions and recommendations by the mathematics teachers in implementing limited face-to-face classes. Results showed that mathematics teachers acquire a sense of positivity because, with almost two (2) years of modular distance learning, teachers become excited to teach again. However, disadvantages occur using this modality that make teachers drained physically and mentally. With inconsistent findings using dissonance theory, the need to resume full in-person instruction was concluded

Perceptions, Challenges and Coping Strategies of Mathematics Teachers in the Implementation of Limited Face-To-Face Classes

This study investigated how mathematics teachers at Ozamiz City School of Arts and Trades perceived the implementation of limited face-to-face classes. The researcher purposively identified ten (10) secondary mathematics teachers, parents, and students who have participated in the implementation of limited face-to-face classes. A semi-structured interview was utilized to interview the Mathematics teachers, parents, and students at OCSAT. All online and offline interviews were recorded and verified because the researcher sought to capture the data precisely and comprehensively. Using Merriam Case Study Model, particularly a three-component triangulation, the outcome is supported by the feedback from parents and students to have an authenticity of results from the main respondents. This model helps identify the perceptions, challenges encountered, coping strategies, and suggestions and recommendations by the mathematics teachers in implementing limited face-to-face classes. Results showed that mathematics teachers acquire a sense of positivity because, with almost two (2) years of modular distance learning, teachers become excited to teach again. However, disadvantages occur using this modality that make teachers drained physically and mentally. With inconsistent findings using dissonance theory, the need to resume full in-person instruction was concluded

Level of awareness on the risk factors and symptoms of prostate cancer and health-seeking behaviors of male residents in selected barangays in Paranaque, City

The study used a descriptive correlational research design with a population of 400 male residents between 40 to 60 years old in selected barangays in Paranaque City. They were selected using purposive sampling technique. A four-part questionnaire was used. The first part was used to identify the socio-demographic variables. The second part was used to measure the level of awareness on the risk factors. While the third part was used to measure the level of awareness on symptoms. Lastly, the fourth part is used to identify the health-seeking behaviors. The data gathered were subjected to statistical treatments such as frequency, mean, standard deviation, t-test for independent mean, F-test or one-way ANOVA, Duncan’s Multiple Range Test, and Pearson r. Based on the finding of the study, the following conclusions were drawn: 1) Majority of the respondents were 40 to 50 years old, Catholic, obtained high school level of education, were single, belonged to the monthly family income group of P40,000 and below, and has no family history of cancer; 2) Most of the respondents have poor awareness on both risk factors and symptoms of prostate cancer; 3) The health-seeking behaviors of the respondents in terms of self-treatment lay advice seeking and medical help seeking in which the commonly exhibited health-seeking behavior was medical help seeking; 4) There were no significant differences in the level of awareness of the respondents on the risks and symptoms of prostate cancer when grouped according to age, religion, and family history of cancer. On the other hand, significant differences occurred on the level of awareness of the respondents on risk factors and symptoms of prostate cancer when grouped according to educational attainment which results to men who have obtained college level have higher level of awareness than those in elementary, high school and vocational; civil status which results to married men have higher level of awareness thank single and widowed/separated men; and monthly family income which results men who belong with a family income of Php 40,001 and above have higher level of awareness than those with a family monthly income of Php 40,000 and below; 5) There were no significant differences in the health-seeking behaviors in terms of self-treatment, lay advise seeking, and medical help seeking when grouped according to age, religion, monthly family income and educational attainment. While, significant differences occurred In the health-seeking behaviors in terms of lay advice seeking when grouped according to civil status which shows that married men tend to seek advices from others compared to those who are single and widowed/separated, and in terms of medical health seeking when grouped according to family with history of cancer; 6) There was a very weak positive correlation between the level of awareness on the risk factors and symptoms of prostate cancer and the health-seeking behaviors in terms of lay advice seeking, and medical help seeking. This may mean that lay advice seeking and medical help seeking increases the level of awareness on risk factors and symptoms on prostate cancer, but not self-treatment

Biocompatibility of a coacervate-based controlled release system for protein delivery to the injured spinal cord

The efficacy of protein-based therapies for treating injured nervous tissue is limited by the short half-life of free proteins in the body. Affinity-based biomaterial delivery systems provide sustained release of proteins, thereby extending the efficacy of such therapies. Here, we investigated the biocompatibility of a novel coacervate delivery system based on poly(ethylene argininylaspartate diglyceride) (PEAD) and heparin in the damaged spinal cord. We found that the presence of the [PEAD:heparin] coacervate did not affect the macrophage response, glial scarring, or nervous tissue loss, which are hallmarks of spinal cord injury. Moreover, the density of axons, including serotonergic axons, at the injury site and the recovery of motor and sensorimotor function were comparable in rats with and without the coacervate. These results revealed the biocompatibility of our delivery system and supported its potential to deliver therapeutic proteins to the injured nervous system