Safe Schools and Zero Tolerance: Policy, Program and Practice in Ontario

This paper examines zero tolerance discipline policies in Ontario’s public school system legislated as the Safe Schools Act (SSA) 2001. The intent of our paper is to argue that the SSA set within a discourse of zero tolerance as the panacea to the problems of violence in schools has had a detrimental impact. Since the SSA is part of the episteme of standardized solutions to complex problems, Ball’s interpretation of “policy as text” and “policy as discourse” serves as the guiding framework for the study in which we examine the perspectives of professionals who implement these measures. In conclusion we state that the discursive frames within which zero tolerance policies are situated have shifted to some extent in order to consider other possibilities to the zero tolerance approach.

Data-adaptive doubly robust instrumental variable methods for treatment effect heterogeneity

We consider the estimation of the average treatment effect in the treated as a function of baseline covariates, where there is a valid (conditional) instrument. We describe two doubly-robust (DR) estimators: a g-estimator and a targeted minimum loss-based estimator (TMLE). These estimators can be viewed as generalisations of the two-stage least squares (TSLS) method to semiparametric models that make weaker assumptions. We exploit recent theoretical results and use data-adaptive estimation of the nuisance parameters for the g-estimator. A simulation study is used to compare standard TSLS with the two DR estimators’ finite-sample performance when using (1) parametric or (2) data-adaptive estimation of the nuisance parameters. Data-adaptive DR estimators have lower bias and improved coverage, when compared to incorrectly specified parametric DR estimators and TSLS. When the parametric model for the treatment effect curve is correctly specified, the g-estimator outperforms all others, but when this model is misspecified, TMLE performs best, while TSLS can result in large biases and zero coverage. The methods are also applied to the COPERS (COping with persistent Pain, Effectiveness Research in Selfmanagement) trial to make inferences about the causal effect of treatment actually received, and the extent to which this is modified by depression at baseline

Óxido nítrico sintasa endotelial en ratones deficientes en Apolipoproteína E.

68 p.La aterosclerosis, agrupada dentro de las enfermedades cardiovasculares, corresponde a una patología que puede afectar a vasos sanguíneos de diferente calibre, disminuyendo el diámetro normal que posibilita la circulación sanguínea, lo que ocurre por una acumulación de lípidos, colesterol, fibrina y células del sistema inmune en la pared de los vasos. El evento previo a la formación de placas de ateroma o aterosclerosis es la disfunción del endotelio, en la cual existe un desequilibrio en la producción de las sustancias vasoactivas sintetizadas por él. Una de las moléculas que mayormente se ve afectada y que cumple un importante rol tanto en la regulación del tono vascular como en la protección del endotelio vascular, es el óxido nítrico sintetizado por la óxido nítrico sintasa endotelial (eNOS), quien ve mermados tanto su contenido como su actividad. El objetivo planteado es determinar y comparar contenido de eNOS de tejido cardiaco de ratones deficientes en Apolipoproteína E (ApoE+/-), un modelo animal de dislipidemia, y de ratones control, sometidos a dieta normal. Las metodologías utilizadas y estandarizadas fueron: la determinación de contenido proteico de tejido cardiaco de ratones ApoE+/- y sus controles, mediante método del ácido bicinconínico (BCA); SDS-PAGE y Western blot, para determinar el contenido de eNOS, eNOS fosforilada, caveolina y tubulina; además la determinación de producción de NO mediante la determinación de contenido de nitrato y nitrito, por el método de Griess. A partir de los resultados obtenidos en esta memoria, se concluye que existe unadisminución del contenido de eNOS en los ratones deficientes en ApoE, sin embargo su actividad no está disminuida, ya que si bien, mediante Western blot se encontró menor contenido de eNOS en tejido cardiaco de ratones ApoE+/-, estos tienen una mayor proporción de eNOS fosforilada y por lo tanto tienen niveles de nitrato y nitrito similares a los ratones control

CVD and oxidative stress

Nowadays, it is known that oxidative stress plays at least two roles within the cell, the generation of cellular damage and the involvement in several signaling pathways in its balanced normal state. So far, a substantial amount of time and effort has been expended in the search for a clear link between cardiovascular disease (CVD) and the effects of oxidative stress. Here, we present an overview of the different sources and types of reactive oxygen species in CVD, highlight the relationship between CVD and oxidative stress and discuss the most prominent molecules that play an important role in CVD pathophysiology. Details are given regarding common pharmacological treatments used for cardiovascular distress and how some of them are acting upon ROS-related pathways and molecules. Novel therapies, recently proposed ROS biomarkers, as well as future challenges in the field are addressed. It is apparent that the search for a better understanding of how ROS are contributing to the pathophysiology of CVD is far from over, and new approaches and more suitable biomarkers are needed for the latter to be accomplished

Correlation between the "68Ga-DOTATATE" uptake at the pituitary region and the response to somatostatin analogues in acromegaly

Orientadores: Heraldo Mendes Garmes, Allan de Oliveira SantosDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências MédicasResumo: Acromegalia é uma doença crônica causada pela hipersecreção do hormônio do crescimento (GH), que estimula a produção de IGF-1 pelas células hepáticas e tecidos sistêmicos, sendo a principal etiologia o somatotropinoma hipofisário. O excesso de GH e IGF-1 está associado a uma série de comorbidades e ao aumento da mortalidade. O tratamento de primeira linha da doença é a ressecção transesfenoidal do adenoma hipofisário secretor de GH, porém, pela prevalência aumentada de macroadenomas ao diagnóstico, muitos pacientes, cerca de 50%, necessitam de tratamento medicamentoso adjuvante e a primeira escolha é o análogo de somatostatina (SSA), que suprime a secreção de GH pelos somatotrofos por meio de sua ligação ao receptor SSTR2. No entanto, cerca de 50% dos pacientes são parcialmente ou totalmente resistentes aos análogos de somatostatina e, portanto, a busca por fatores preditivos de resposta ao medicamento é de relevante valia para individualizar o tratamento medicamentoso. Diante do cenário de emergência do "68Ga-DOTATATO" PET/CT como método padrão ouro no diagnóstico e seguimento de tumores neuroendócrinos gastroenteropancreáticos, que também expressam SSTR, nosso objetivo específico foi avaliar se a captação (SUV max) do radiofármaco na região hipofisária de pacientes com o diagnóstico de acromegalia em uso de SSA seria útil como preditor de reposta ao medicamento. Para tanto, foram recrutados 15 pacientes com acromegalia em uso de SSA há pelo menos 6 meses, acompanhados no serviço de endocrinologia do Hospital de Clínicas da Universidade Estadual de Campinas - UNICAMP, que foram submetidos ao "68Ga-DOTATATO" PET/CT no serviço de medicina nuclear. Os pacientes foram divididos em um grupo com resposta completa ao SSA (n = 5), definida como GH < 1 µg/L e IFG-1 na faixa de normalidade para sexo e idade, e um grupo que não atingiu tal critério (n = 10). Como resultado, não encontramos maior SUV max no grupo com resposta completa (p = 0.0576), porém evidenciamos uma relação inversa significativa entre valores de GH pós uso de SSA e o SUV max na região da sela túrcica, possivelmente refletindo a maior expressão tumoral de SSTR2 nos pacientes que respondem ao tratamento. Em relação a outras variáveis, como sexo, idade, níveis de GH e IGF-1, intensidade de sinal em T2 na RNM não encontramos associação com a resposta aos SSA. Dessa forma, após essa avaliação inicial, concluímos que o "68Ga-DOTATATO" PET/CT deve ser, ainda, mais estudado para avaliar sua utilidade no seguimento de pacientes acromegálicosAbstract: Acromegaly is a chronic disease caused by growth hormone (GH) hypersecretion, which stimulates the production of IGF-1 by liver cells and systemic tissues, and the main cause is pituitary somatotropinoma. GH and IGF-1 excess is associated with many comorbidities and increased mortality. The first line treatment of the disease is the transsphenoidal resection of the GH-secreting pituitary adenoma. However, due to the increased prevalence of macroadenomas at diagnosis, many patients, about 50%, need adjuvant drug treatment and the first choice is the analogue of somatostatin (SSA), which suppresses GH secretion by somatotrophs by binding to the SSTR2 receptor. However, about 50% of patients are partially or totally resistant to somatostatin analogues, so the search for predictive factors of adequate response is of great value in individualizing drug treatment. Because of the emergence of "68Ga-DOTATATE" PET/CT as the gold standard method in the diagnosis and follow-up of gastroenteropancreatic neuroendocrine tumors, which also express SSTR2, our specific objective was to evaluate whether radiopharmaceutical uptake (SUV max) in the pituitary region of patients with acromegaly diagnosis on SSA therapy would be useful as a predictor of drug response. For this, 15 acromegalics patients using SSA for at least 6 months were recruited at the endocrinology service of the Hospital de Clínicas of Universidade Estadual de Campinas - UNICAMP and underwent "68Ga-DOTATATE" PET / CT at the nuclear medicine service. Patients were divided into a group with complete SSA response (n = 5), defined as GH <1 µg / L and IFG-1 in the normal range for gender and age, and a group that did not meet these criteria (n = 10). As a result, we did not find out a higher SUV max in the full-response group (p = 0.0576) to SSA, however we recognized a significant inverse relationship between postoperative GH values and the SUV max in the sella turcica, probably reflecting tumor SSTR2 expression. Regarding other variables, such as gender, age, T2 signal intensity on MRI, we found no association with the response to SSA. Thus, after this initial evaluation, "68Ga-DOTATATE" PET/CT should be better studied to assess its usefulness in the follow-up of acromegalic patientsMestradoClinica MedicaMestra em Ciência

Propuestas para la mejora de la competitividad del sector exportador de flores cortadas en el Ecuador

SE REALIZA UN DIAGNOSTICO DE EVOLUCION DEL SECTOR PRODUCTOR Y EXPORTADOR, VARIEDADES QUE SE COMERCIAN,PRINCIPALES PRODUCTORES Y COMPETIDORES DE FLORES A NIVEL MUNDIAL. MERCADO DE DESTINOS PARA LOS PRODUCTOS FLORICOLAS ECUATORIANOS. SE DETERMINA BENEFICIOS SOCIALES Y ECONOMICOS PARA LA APLICACION DE SELLOS ECOLOGICOS SOCIALES PARA LA PRODUCCION DE FLORES.. SE ANALIZA EL ROL DEL TRANSPORTE EN EL COMERCIO INTERNACIONAL Y LA COMPETENCIA DE LA UNA ECONOMIA GLOBALIZADA. OBJETIVO FUNDAMENTAL ES SATISFACER LA DEMANDA LOCAL Y CONSEGUIR DE ALGUNA MANERA INGRESAR EL PRODUCTO A ESTADOS UNIDOS

Monitoring the hydrothermal growth of cobalt spinel water oxidation catalysts - from preparative history to catalytic activity

The hydrothermal growth of cobalt oxide spinel (Co₃O₄) nanocrystals from cobalt acetate precursors was monitored with in situ powder X‐ray diffraction (PXRD) in combination with ex situ electron microscopy and vibrational spectroscopy. Kinetic data from in situ PXRD monitoring were analyzed using Sharp‐Hancock and Gualtieri approaches, which both clearly indicate a change of the growth mechanism for reaction temperatures above 185°C. This mechanistic transition goes hand in hand with morphology changes that notably influence the photocatalytic oxygen evolution activity. Complementary quenching investigations of conventional hydrothermal Co₃O₄ growth demonstrate that these insights derived from in situ PXRD data provide valuable synthetic guidelines for water oxidation catalyst production. Furthermore, the ex situ analyses of hydrothermal quenching experiments were essential to assess the influence of amorphous cobalt‐containing phases arising from the acetate precursor on the catalytic activity. Thereby, we illustrate how the efficient combination of a single in situ technique with ex situ analyses paves the way to optimize parameter‐sensitive hydrothermal production processes of key energy materials