Erziehen zum Menschsein

L’articolo si avvia con un’analisi dell’esperienza dell’apprendimento focalizzata sui seguenti tratti essenziali: la relazione, la libertà, l’intelletto e la sfera affettiva. L’educazione è poi definita come accompagnamento del discente verso un’esperienza più profondamente umana della realtà. Questa definizione impone di giudicare la distinzione concettuale tra istruzione e educazione come riduttiva: l’istruzione è, infatti, essa stessa educante per il metodo, che insegna il confronto con i propri limiti e introduce a una posizione di apertura al reale, e per i contenuti, che arricchiscono di consapevolezza l’esperienza della realtà. In questo percorso è indispensabile l’educazione ai valori, tematizzata nella seconda parte dell’articolo con una proposta didattica di educazione alla cittadinanza democratica. (DIPF/Orig.)Dieser Beitrag beginnt mit einer Analyse individueller Lernerfahrungen. Diese Analyse konzentriert sich auf folgende Merkmale: Beziehung, Freiheit, Intellekt und Emotion. Bildung wird als die Hinführung der Lernenden zu einer tieferen menschlichen Erfahrung der Wirklichkeit betrachtet. Diese Definition beinhaltet, dass die konzeptuelle Unterscheidung zwischen Bildung und Erziehung minimiert wird. Bildung ist in gewisser Weise auch erziehend aufgrund ihrer Aufgabe, die eigenen Grenzen kennen zu lernen und sich mit dieser Wirklichkeit auseinander zu setzen. Ebenso sensibilisieren die Bildungsinhalte die Wirklichkeitserfahrungen der Lernenden. Im zweiten Teil des Beitrags wird die Unverzichtbarkeit einer Wertebildung aufgezeigt. Diese wird anhand eines didaktischen Beispiels zur Förderung der Entwicklung eines demokratischen Bewusstseins veranschaulicht. (DIPF/Orig.

Evaluation of performance fatigability through surface EMG in health and muscle disease: state of the art

In literature, it is commonly reported that the progress of performance fatigability may be indirectly assessed through the changes in the features of the surface electromyogram (sEMG) signal. In particular, during isometric constant force contractions, changes in the sEMG signal are caused by several physiological factors, such as a decay in muscle fibers conduction velocity (CV), an increase of the degree of synchronization between the firing times of simultaneously active motor units (MUs), by the central nervous system, and a reduction of the recruitment threshold and a modulation of MUs firing rate. Amplitude and spectral parameters may be used to characterize the global contributions to performance fatigability, such as MU control properties and fiber membrane properties, or central and peripheral factors, respectively. In addition, being CV a physiological parameter, its estimation is of marked interest to the study of fatigue both in physiological and in presence of neuromuscular diseases

The school and the truth

La tesi dell’articolo afferma l’essenzialità che riveste, per l’istituzione scolastica, il principio della verità, nel senso aristotelico della costruzione di nessi tra i discenti e la realtà. Nessi conoscitivi che fondano, da un lato il rispetto del vincolo alla neutralità dell’insegnamento e dall’altro lato l’educazione alla cittadinanza democratica. Nessi valutativi che, nella loro sostanza, rappresentano un orientamento alla crescita degli allievi e nella loro forma accompagnano quest’ultimi nel mettersi costamente in questione. Sviluppando queste riflessioni, l’articolo si muove continuamente tra teoria e pratica, offrendo altresì due sezioni con spunti pratici per la formulazione delle valutazioni e per la gestione dei comportamenti scorretti. (DIPF/Orig.)This article’s thesis affirms the essentialness of the principle of truth for the educational institution, in the Aristotelian sense of building links between learners and reality. Cognitive links that are the basis, on the one hand, of respect for the constraint to the neutrality of teaching and, on the other hand, education for democratic citizenship. Finally, evaluative links which, in their substance, represent an orientation to the growth of students and in their form accompany the latter in constantly questioning themselves. Developing these reflections, this article moves continuously between theory and practice, also offering two sections with ideas for formulating assessments and for managing incorrect behavior. (DIPF/Orig.

Preparing an Effective School Trip: Precision Work

To provide a possible interpretation of the passive attitude often exhibited by pupils in the context of school trips, the article does not follow the path of moralistic judgement, but starts from the essence of the teaching profession, which consists in showing the world to the students. The article adopts the thesis of the presence, in many school trips, of an excessive cognitive load and affirms the need to devote the same attention to teaching in these learning contexts as in class work. Graduality is proposed as the key to a learning experience based on a motivation that arises from the discovery of reality

Identification of muscle innervation zones using linear electrode arrays: a fundamental step to measure fibers conduction velocity

Fiber conduction velocity (CV) is a parameter correlated to the physiological membrane properties of the skeletal muscle fibers. Changes in muscle fiber CV are correlated to the gradation of force and fatigue, and can be measured by means of surface electromyography EMG (sEMG). sEMG measurement of CV during muscle contractions requires the correct identification of the skeletal muscle innervation zone (IZ). In superficial muscles, IZ location can be detected using linear electrode arrays and visually identified as the point of inversion of the detected motor unit action potential (MUAP) propagation. In the present work, we present a method for the effective and fast detection of the IZ location, through the following procedures: (1) identification of the target superficial muscle considering the muscle fiber architecture; (2) electrode array selection based on interelectrode distance and number of electrodes; (3) subject training to perform submaximal isometric contractions of the target muscle/s; (4) electrode array positioning along the muscle surface to investigate the IZ position during the contractions by visual identification of MUAP patterns

Enhanced cardiovascular pressor reactivity to norepinephrine in mild renal parenchymal disease

Enhanced cardiovascular pressor reactivity to norepinephrine in mild renal parenchymal disease. The cardiovascular pressor responsiveness to infused norepinephrine (NE) or angiotensin II (AII) as related to endogenous plasma NE or renin levels was assessed in 20 patients with mild parenchymal kidney disease (plasma creatinine 2.20 ± 0.58 mg/dl, ± SEM) and in 20 normal subjects approximately matched for sex and age. The two groups did not differ significantly in mean body weight, heart rate, blood volume, plasma electrolytes, exchangeable or urinary sodium, plasma aldosterone, epinephrine and renin levels, or AII threshold or pressor doses. Basal (including pre-infusion) plasma NE levels, the relationship between plasma NE measured during NE infusion and the corresponding NE infusion rate, as well as the total plasma clearance of NE (5.0 ± 0.8 vs. 5.5 ± 0.5 liter/min) also did not differ significantly between the two groups. In contrast, the threshold or pressor doses of infused NE decreased significantly in the patients with kidney disease (94 ± 11 vs. 134 ± 14 ng/kg/min and 21 ± 3 vs. 40 ± 7 ng/ kg/min; P < 0.05). Moreover, based on analysis of covariance, the individual pressor doses as related to basal plasma NE levels were distributed differently (P < 0.01) between the patients and normal subjects. These findings suggest that the kinetics of plasma NE are unaltered largely in early stage kidney disease. However, such patients tend to develop an exaggerated pressor responsiveness to NE in the presence of normal plasma NE levels. This disturbance may favor the development of hypertension.Stimulation de la réactivité pressive cardiovasculaire à la noradrénaline dans les néphropathies modérées. La réponse pressive cardiovasculaire après perfusion de noradrénaline (NE) ou d'angiotensine II (AII) en fonction des concentrations endogènes de NE ou de rénine plasmatiques a été étudiée chez 20 malades ayant une maladie rénale parenchymateuse modérée (créatininémie 2,20 ± 0,58 (± SEM) mg/dl) et chez 20 sujets normaux d'âge et de sexe voisins. Les deux groupes ne différaient pas significativement par le poids corporel moyen, le rythme cardiaque, le volume sanguin, les électrolytes plasmatiques, le sodium échangeable ou urinaire, l'aldostérone plasmatique, les niveaux d'adrénaline et de rénine, ou les doses seuils ou pressives d'All. Les concentrations plasmatiques de NE basales (y compris les valeurs avant perfusion), la relation entre la NE plasmatique mesurée pendant la perfusion de NE et la vitesse de perfusion de NE correspondante, ainsi que la clearance plasmatique totale de NE (5,0 ± 0,8 contre 5,5 ± 0,5 1/ mn) ne différaient également pas entre les deux groupes. A l'inverse, les doses seuils ou pressives de NE perfusées étaient significativement diminuées chez les malades ayant une néphropathie (94 ± 11 contre 134 ± 14 ng/kg/mn et 21 ± 3 contre 40 ± 7 ng/kg/mn; P < 0,05). En outre, par analyse de covariance, les doses pressives individuelles en fonction des concentrations plasmatiques basales de NE étaient distribuées différemment (P < 0,01) entre les malades et les sujets normaux. Ces résultats suggèrent que la cinétique de la NE plasmatique est en grande partie inchangée au cours des néphropathies au stade initial. Cependant les malades tendent à développer une réponse pressive exagérée à la NE en présence de concentrations plasmatiques de NE normales. Cette anomalie pourrait favoriser le développement d'une hypertension

Cardiovascular Pressor Reactivity After Chronic Converting Enzyme Inhibition

In addition to inhibiting the formation of angiotensin II, chronic converting enzyme inhibition may affect other blood pressure modulating factors. The influence of an 8 week treatment phase with Cilazapril on the activity of the renin-angiotensin-aldosterone and sympathetic nervous systems, the pressor reactivity to infused angiotensin II or norepinephrine, the chronotropic response to isoproterenol, and body sodium and plasma atrial natriuretic peptide concentrations was assessed in 11 normal subjects and 12 patients with essential hypertension. As compared to a 4 week placebo phase, Cilazapril decreased arterial pressure in both study groups (from 124/83 ± 9/6 to 114/77 ± 9/5 mm Hg and from 143/102 ± 13/7 to 137/96 ± 10/10 mm Hg; Ρ < .025); exchangeable sodium (−158 mmol and, respectively, −104 mmol) and upright plasma aldosterone (−24% and −15%) also tended to fall. Heart rate, the chronotropic response to posture or isoproterenol, plasma norepinephrine levels, the concentration/pressor response curve to norepinephrine, plasma atrial natriuretic peptide concentration, plasma angiotensin II and the responses of blood pressure or plasma aldosterone to angiotensin II were unchanged after 8 weeks of Cilazapril. Plasma renin activity increased (+175% to + 650%) These findings indicate that the blood pressure lowering effect of Cilazapril in the stable phase of pharmacological intervention is not associated with modifications of sympathetic-dependent pressor reactivity or ^-adrenergic sensitivity. Plasma angiotensin II concentration and angiotensin II-dependent pathways including the pressor and aldosterone responsiveness to angiotensin II are also unchanged. Am J Hypertens 1991;4:348-35

Relationship between Isometric Muscle Force and Fractal Dimension of Surface Electromyogram

The relationship between fractal dimension of the surface electromyogram (sEMG) and the intensity of muscle contraction is still controversial in simulated and experimental conditions. To support the use of fractal analysis to investigate myoelectric fatigue, it is crucial to establish the interdependence between fractal dimension and muscle contraction intensity. We analyzed the behavior of fractal dimension, conduction velocity, mean frequency, and average rectified value in twenty-eight volunteers at nine levels of isometric force. sEMG was obtained using bidimensional arrays in the biceps brachii muscle. The values of fractal dimension and mean frequency increased with force unless a plateau was reached at 30% maximal voluntary contraction. Overall, our findings suggest that, above a certain level of force, the use of fractal dimension to evaluate the myoelectric manifestations of fatigue may be considered, regardless of muscle contraction intensity

Sodium, renin, aldosterone, catecholamines, and blood pressure in diabetes mellitus

Sodium, renin, aldosterone, catecholamines, and blood pressure in diabetes mellitus. Interrelations among plasma renin activity (PRA), aldosterone and Cortisol levels, blood volume, exchangeable sodium, urinary catecholamines, and blood pressure were studied in 35 normal subjects and 60 age-matched non-azotemic patients with diabetes mellitus (60% with hypertension, 15% with orthostatic hypotension). Basal PRA, plasma aldosterone, cortisol, blood volume, plasma potassium, and urinary electrolytes were comparable in diabetic and normal subjects. Diabetic patients, however, had a 10% increase in body sodium (P < 0.01), and 8% of them showed normal postural PRA responses and subnormal aldosterone responses; 22% had subnormal PRA and normal aldosterone responses, and 17% had subnormal responses of PRA and aldosterone. Non-PRA-related aldosterone responses could not be explained by ACTH or electrolytes. Orthostatic decreases in blood pressure correlated (P < 0.01) with both catecholamine excretion and basal PRA. This suggests that in diabetes mellitus, body sodium is increased. Basal PRA and plasma aldosterone are usually normal, but their postural responses are frequently impaired. Absent aldosterone responses, despite normal PRA responsiveness, may reflect an adrenal abnormality or an ineffective form of renin. Marked postural aldosterone stimulation, unrelated to PRA, ACTH, or electrolytes, points to a potent unknown factor in aldosterone control. Low levels of free peripheral catecholamines and PRA may be complementary factors contributing to postural hypotension.Sodium, rénine, aldostérone, catécholamines et pression artérielle dans le diabèté sucré. Les inter-relations entre l'activité rénine plasmatique (PRA), les concentrations d'aldostérone et de cortisol, le volume sanguin, le sodium échangeable, les catécholamines urinaires et la pression artérielle ont été étudiées chez 35 sujets normaux et 60 malades atteints de diabété, sans insuffisance rénale et dont les âges étaient appariés (60% avaient une hypertension et 15% une hypotension orthostatique). La PRA de base, l'aldostérone et le Cortisol plasmatiques, le volume sanguin, le potassium plasmatique et les électrolytes urinaires étaient comparables chez les diabétiques et les sujets normaux. Les malades diabétiques, cependant, ont une augmentation de 10% de leur sodium corporel (P < 0,01). Huit pour cent d'entre eux ont une réponse posturale de PRA normale et une réponse de l'aldostérone inférieure à la normale, 22% ont une réponse de PRA inférieure à la normale et une reponse de l'aldosterone normale, et 17% ont des réponses de PRA et de l'aldostérone inférieures à la normale. Les réponses de l'aldostérone sans rapport avec PRA ne peuvent pas être expliquées par l'ACTH ou les électrolytes. Les diminutions de la pression artérielle liées à l'orthostatisme sont correlées (P < 0,01) à la fois avec l'excrétion de catécholamines et la PRA de base. Ceci suggére qu'au cours du diabéte le sodium corporel est augmenté. La PRA et l'aldosterone de base sont souvent normales mais leur réponse posturale est souvent modifiée. L'absence de réponse de l'aldosterone malgré une réponse normale de PRA peut traduire une anomalie surrénale ou une forme de rénine inefficace. Une stimulation posturale importante de l'aldostérone non expliquée par la PRA, l'ACTH ou les électrolytes oriente vers un facteur inconnu mais puissant du contrôle de la sécrétion d'aldostérone. Des concentrations basses de catécholamines libres et une PRA basse peuvent être des facteurs complémentaires qui participent à l'hypotension posturale

Sodium, renin, aldosterone, catecholamines, and blood pressure in diabetes mellitus

Sodium, renin, aldosterone, catecholamines, and blood pressure in diabetes mellitus. Interrelations among plasma renin activity (PRA), aldosterone and Cortisol levels, blood volume, exchangeable sodium, urinary catecholamines, and blood pressure were studied in 35 normal subjects and 60 age-matched non-azotemic patients with diabetes mellitus (60% with hypertension, 15% with orthostatic hypotension). Basal PRA, plasma aldosterone, cortisol, blood volume, plasma potassium, and urinary electrolytes were comparable in diabetic and normal subjects. Diabetic patients, however, had a 10% increase in body sodium (P < 0.01), and 8% of them showed normal postural PRA responses and subnormal aldosterone responses; 22% had subnormal PRA and normal aldosterone responses, and 17% had subnormal responses of PRA and aldosterone. Non-PRA-related aldosterone responses could not be explained by ACTH or electrolytes. Orthostatic decreases in blood pressure correlated (P < 0.01) with both catecholamine excretion and basal PRA. This suggests that in diabetes mellitus, body sodium is increased. Basal PRA and plasma aldosterone are usually normal, but their postural responses are frequently impaired. Absent aldosterone responses, despite normal PRA responsiveness, may reflect an adrenal abnormality or an ineffective form of renin. Marked postural aldosterone stimulation, unrelated to PRA, ACTH, or electrolytes, points to a potent unknown factor in aldosterone control. Low levels of free peripheral catecholamines and PRA may be complementary factors contributing to postural hypotension.Sodium, rénine, aldostérone, catécholamines et pression artérielle dans le diabèté sucré. Les inter-relations entre l'activité rénine plasmatique (PRA), les concentrations d'aldostérone et de cortisol, le volume sanguin, le sodium échangeable, les catécholamines urinaires et la pression artérielle ont été étudiées chez 35 sujets normaux et 60 malades atteints de diabété, sans insuffisance rénale et dont les âges étaient appariés (60% avaient une hypertension et 15% une hypotension orthostatique). La PRA de base, l'aldostérone et le Cortisol plasmatiques, le volume sanguin, le potassium plasmatique et les électrolytes urinaires étaient comparables chez les diabétiques et les sujets normaux. Les malades diabétiques, cependant, ont une augmentation de 10% de leur sodium corporel (P < 0,01). Huit pour cent d'entre eux ont une réponse posturale de PRA normale et une réponse de l'aldostérone inférieure à la normale, 22% ont une réponse de PRA inférieure à la normale et une reponse de l'aldosterone normale, et 17% ont des réponses de PRA et de l'aldostérone inférieures à la normale. Les réponses de l'aldostérone sans rapport avec PRA ne peuvent pas être expliquées par l'ACTH ou les électrolytes. Les diminutions de la pression artérielle liées à l'orthostatisme sont correlées (P < 0,01) à la fois avec l'excrétion de catécholamines et la PRA de base. Ceci suggére qu'au cours du diabéte le sodium corporel est augmenté. La PRA et l'aldosterone de base sont souvent normales mais leur réponse posturale est souvent modifiée. L'absence de réponse de l'aldosterone malgré une réponse normale de PRA peut traduire une anomalie surrénale ou une forme de rénine inefficace. Une stimulation posturale importante de l'aldostérone non expliquée par la PRA, l'ACTH ou les électrolytes oriente vers un facteur inconnu mais puissant du contrôle de la sécrétion d'aldostérone. Des concentrations basses de catécholamines libres et une PRA basse peuvent être des facteurs complémentaires qui participent à l'hypotension posturale