Homeschooling and the criticism of school: hybridisms and educational (dis)continuities

Desde os anos 1960, o homeschooling apresenta dinâmicas de crescimento atualizadas nos diagnósticos da crise do capitalismo e dos sistemas educativos. Por ser praticado por famílias próximas do progressismo libertário, do cristianismo conservador ou de outras inspirações axiológicas, a abordagem investigativa presente neste texto pressupôs romper com uma visão unívoca e alheia à sua diversidade e aos diferentes graus de (in)formalidade dos quotidianos educativos de crianças e de jovens que caracterizam este fenómeno educativo. Procura-se captar as especificidades do ensino doméstico (ED) em Portugal e a sua crescente expressão social e educacional e reflete-se sobre os sentidos das aprendizagens que ele encerra. Conclui-se que o ED parece ser contrário aos horizontes formativos da criança segundo o interesse da sociedade, sendo omisso sobre o seu papel na emancipação dos sujeitos. Confrontam-se a escola e o seu modo de funcionamento a partir do racional do ED, à procura de novas epistemologias e de novas linhas de pesquisa.Since the 1960s, homeschooling has shown growth dynamics updated by the diagnosis of the crisis of capitalism and of educational systems. Because it is practiced by families close to libertarian progressivism, conservative Christianity, or other axiological inspirations, this paper’s approach sought to break with a univocal conception alien to its diversity and to the different degrees of (in)formality of the children’s and young people’s educational daily lives inherent to this educational practice. Therefore, this paper seeks to understand the specificities of Portuguese homeschooling and its increasing social and educational expression, and to reflect on the meanings of the learning it entails. Being unclear about its role on the emancipation of the subjects, homeschooling seems to be contrary to the educational horizons of the child according to the interests of the whole society. This paper confronts school and its way of functioning with the homeschooling rationale in order to search for new epistemologies and new lines of research.info:eu-repo/semantics/publishedVersio

Explaining the Atypical Reaction Profiles of Heme Enzymes with a Novel Mechanistic Hypothesis and Kinetic Treatment

Many heme enzymes show remarkable versatility and atypical kinetics. The fungal extracellular enzyme chloroperoxidase (CPO) characterizes a variety of one and two electron redox reactions in the presence of hydroperoxides. A structural counterpart, found in mammalian microsomal cytochrome P450 (CYP), uses molecular oxygen plus NADPH for the oxidative metabolism (predominantly hydroxylation) of substrate in conjunction with a redox partner enzyme, cytochrome P450 reductase. In this study, we employ the two above-mentioned heme-thiolate proteins to probe the reaction kinetics and mechanism of heme enzymes. Hitherto, a substrate inhibition model based upon non-productive binding of substrate (two-site model) was used to account for the inhibition of reaction at higher substrate concentrations for the CYP reaction systems. Herein, the observation of substrate inhibition is shown for both peroxide and final substrate in CPO catalyzed peroxidations. Further, analogy is drawn in the “steady state kinetics” of CPO and CYP reaction systems. New experimental observations and analyses indicate that a scheme of competing reactions (involving primary product with enzyme or other reaction components/intermediates) is relevant in such complex reaction mixtures. The presence of non-selective reactive intermediate(s) affords alternate reaction routes at various substrate/product concentrations, thereby leading to a lowered detectable concentration of “the product of interest” in the reaction milieu. Occam's razor favors the new hypothesis. With the new hypothesis as foundation, a new biphasic treatment to analyze the kinetics is put forth. We also introduce a key concept of “substrate concentration at maximum observed rate”. The new treatment affords a more acceptable fit for observable experimental kinetic data of heme redox enzymes

Deconstructing dogma: Nonoperative management of small bowel obstruction in the virgin abdomen

Management of small bowel obstruction (SBO) has become more conservative, especially in those patients with previous abdominal surgery (PAS). However, surgical dogma continues to recommend operative exploration for SBO with no PAS. With the increased use of computed tomography imaging resulting in more SBO diagnoses, it is important to reevaluate the role of mandatory operative exploration. Gastrografin (GG) administration decreases the need for operative exploration and may be an option for SBO without PAS. We hypothesized that the use of GG for SBO without PAS will be equally effective in reducing the operative exploration rate compared with that for SBO with PAS. A post hoc analysis of prospectively collected data was conducted for patients with SBO from February 2015 through December 2016. Patients younger than 18 years, pregnant patients, and patients with evidence of hypotension, bowel strangulation, peritonitis, closed loop obstruction or pneumatosis intestinalis were excluded. The primary outcome was operative exploration rate for SBO with or without PAS. Rate adjustment was accomplished through multivariate logistic regression. Overall, 601 patients with SBO were included in the study, 500 with PAS and 101 patients without PAS. The two groups were similar except for age, sex, prior abdominal surgery including colon surgery, prior SBO admission, and history of cancer. Multivariate analysis showed that PAS (odds ratio [OR], 0.47; p = 0.03) and the use of GG (OR, 0.11; p < 0.01) were independent predictors of successful nonoperative management, whereas intensive care unit admission (OR, 16.0; p < 0.01) was associated with a higher likelihood of need for operation. The use of GG significantly decreased the need for operation in patients with and without PAS. Patients with and without PAS who received GG had lower rates of operative exploration for SBO compared with those who did not receive GG. Patients with a diagnosis of SBO without PAS should be considered for the nonoperative management approach using GG. Therapeutic, level IV