Innovation, systemic appropriation and prevention in the granite mining sector: The case of humidification.

BACKGROUND: This research was conducted in the Brazilian granite mining sector. After epidemiological studies, it was established that professional pneumoconiosis is related to the inhalation of dust. Therefore, the Brazilian mining health and safety regulatory standard made it compulsory to provide humidification throughout the extraction and mineral treatment processes. OBJECTIVE: To develop the concept of systemic appropriation of the technological innovations that aim to protect the worker's health. Until now, appropriation has usually been presented in its individual dimensions. In this article, the focus is placed on the collective and organizational aspects of this appropriation. METHODS: Two methodological approaches were used: interviews with the different individuals involved in order to report the history of the implementation of technical devices which meet the humidification norm; and ergonomic analysis of the work of the operators who used these devices. RESULTS: The appropriation of the technical devices occurred at two distinct levels: 1) Individual, related to the direct contact of the operator with the instrument; 2) Systemic, as the effects of the innovation propagated through the system affecting interdependent tasks, adaptation of the work organization and new production strategies. CONCLUSIONS: The implementation of prevention norms require innovations which are necessarily accompanied by transformations in the companies' techniques, work and management.

A novel, self-correcting membrane coating technique.

A novel coating process, leading to formation of uniform, defect-free coating on solid dosage forms, is proposed. The coating process, termed "diffusion-controlled interfacial complexation," involves a chemical reaction between a reactant incorporated in the solid unit to be coated and a polymer solution, forming the coating medium. The reaction results in the formation of an insoluble reactant-polymer film around the solid. The rate of film/membrane formation is controlled by the rate of diffusion of reactant through the reactant-polymer film. In the model system, calcium acetate was selected as the reactant and algin as the polymer. The coating process was mathematically characterized in terms of rate of increase in film thickness, film weight, and depletion of reactant. Compressed tablets coated using the above process provided zero-order release in distilled water.

Skin-testing with neurotransmitters in schizophrenic patients.

Pilot data are presented on a methodology to study a profile of simultaneous reactivity to intradermally injected norepinephrine, dopamine, serotonin, and histamine. The subject groups were young and old schizophrenics on medication and young control volunteers. Skin reactivity in terms of vasoconstriction, vasodilation, and whealing was measured over the course of 3 hours after the injections. Although interpretation of the results is limited by several sources of confounding error and the small number of subjects, the data suggest that skin-test profiles are sensitive enough to yield significant differences between the groups, particularly in the area of vasoconstriction. Further, abnormal skin reactivity may mirror the hypothesized alterations in CNS neurotransmitter physiology in schizophrenic patients.

Dextroamphetamine with morphine: respiratory effects.

The combination of dextroamphetamine and morphine has been shown to be synergistic for analgesia and antagonistic for most other effects. However, the claim that dextroamphetamine antagonizes the respiratory depression caused by morphine has not been well substantiated. In this double-blind study, we investigated respiratory effects, including resting respiration, isohypercapnic ventilation, CO2 response, dose response, and duration of these effects with dextroamphetamine alone and in combination with morphine. Dextroamphetamine alone (0.215 mg/kg) caused increases in minute ventilation and a leftward shift of the CO2 response curve that lasted for less than 2 hours. Dextroamphetamine combined with low-dose morphine (0.15 mg/kg) antagonized respiratory depression throughout the 5-hour observation period. Dextroamphetamine combined with high-dose morphine (0.30 mg/kg) was unable to completely antagonize depressed ventilation, and some residual effects of morphine persisted at 23 hours.

Effect of formulation and process variables on bioequivalency of nitrofurantoin I: preliminary studies.

Fifty-two combinations of nitrofurantoin were developed to assess the effect of dosage form type, particle size, diluent, and process on in vitro availability. With the official procedure and conditions, dissolution rates fell in a 66-fold range. Statistical analysis of the dissolution rates indicated no significant differences as a result of particle size, processing method, or compression force. The diluent choice and dosage form type significantly influenced the dissolution rate. Based on in vitro screening, six formulations presenting a broad range of dissolution rates were selected for further study relating to human bioavailability and bioequivalence.

Effect of formulation and process variables on bioequivalency of nitrofurantoin II: in vivo-in vitro correlation.

Based on preliminary in vitro evaluation, six formulations presenting a broad range of dissolution rates were selected for bioequivalency determination in a randomized complete block crossover. In vitro-in vivo correlations were developed relating cumulative percent dissolved to cumulative percent excreted. These correlations appear to be useful for comparing different formulations as well as different batches of the same formulation.

A simplified technique for in vivo analysis of sister-chromatid exchanges using 5-bromodeoxyuridine tablets.

A small tablet of 5-bromodeoxyuridine (BrdU), implanted subcutaneously in a mouse, provides sustained release of base analog sufficient to effect substitution of DNA throughout an entire replication period. As illustrated by studies of mouse bone-marrow and spleen cells in the presence or absence of cyclophosphamide, this depot method of BrdU administration greatly simplifies in vivo analysis of sister-chromatid-exchange formation.