1. The relation of somatosensory cortex (SI) neuronal activity to actively maintained limb posture was examined by recording from single neurons in the SI of monkeys trained to hold the forearm at different pronation-supination postures and to exert different directions and magnitudes of steady torque. 2. Neurons related to limb position were, in most cases (89%), also related to torque exerted by the limb. Very few neurons related to only position or only torque were found. 3. Two categories of position- and torque-related neurons were found, type 1 and type 2. Type 1 eurneuronal activity resembled the pattern of activity seen in the pronator and supinator muscles; neurons more active with supinating torque also became more active with supinated position, while neurons related to pronating torque were also related to pronated position. Type 2 neurons had a noncongruent relation to position and torque; neurons more active with supinating torque became more active with pronated position, while neurons related to pronating torque were related to supinated position. 4. Position- and torque-related neurons were characterized by having predominantly noncutaneous peripheral inputs and were concentrated in two SI regions identified as area 3a and area 2. 5. It is hypothesized that during actively held limb postures, the activity of the type 1 and type 2 neuronal populations in SI is sufficient to signal uniquely the steady-state position of the limb and the force exerted by the limb.

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Sewage sludge from the galvanic industry represents a problem to the environment, due to its high metal content that makes it a hazardous waste and must be treated or disposed of properly. This study aimed to evaluate the sludge from three galvanic industries and determine its possible use as catalysts for the synthesis of materials. Catalyst was obtained from a thermal process based on dried between 100–120 °C and calcination of sludges between 400 to 700 °C. The physical–chemical properties of the catalyst were analyzed by several techniques as physisorption of N2 and chemisorption of CO of the material. Catalytic activity was analyzed by thermogravimetric analysis of a thermo-catalytic decomposition of crude oil. The best conditions for catalyst synthesis were calcination between 400 and 500 °C, the temperature of reduction between 750 and 850 °C for 15 min. The catalytic material had mainly Fe as active phase and the specific surface between 17.68–96.15 m2·g−1, the catalysts promote around 6% more weight-loss of crude oil in the thermal decomposition compared with assays without the catalyst. The results show that the residual sludge of galvanic industries after thermal treatment can be used as catalytic materials due to the easiness of synthesis procedures required, the low E-factor obtained and the recycling of industrial waste promoted.

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