O objetivo deste trabalho é demonstrar que a morte dos trabalhadores assalariados rurais, cortadores de cana, advém do pagamento por produção. Os processos de produção e de trabalho vigentes no Complexo Agroindustrial Canavieiro foram concebidos objetivando a produtividade crescente do trabalho e, combinados ao pagamento por produção, provocam a necessidade de os trabalhadores aumentarem o esforço despendido no trabalho. O crescimento do dispêndio de energia e do esforço para cortar mais cana provoca ou a morte dos trabalhadores ou a perda precoce de capacidade de trabalho.

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This work describes the production of two clinically relevant metal radioisotopes [Formula: see text] and [Formula: see text] with a medical cyclotron by the irradiation of liquid targets. New results are presented for the implementation of this methodology in a fully automated system, using commercially available equipment. Liquid target solutions containing enriched [Formula: see text] and [Formula: see text] were loaded, bombarded and transferred to synthesis modules where a purified solution containing the desired radiometal is obtained and can then be used to further radiolabeling within only one hour after End-Of-Bombardment (EOB). Typical production runs using enriched material lead to the production of 5 GBq and 6 GBq (0.14 MBq/([Formula: see text]Ah ⋅ mg) and 1.5 MBq/([Formula: see text]Ah ⋅ mg)) of [Formula: see text] and [Formula: see text]; although the technique can be used to obtain up to 25 GBq and 40 GBq, respectively, by simply scaling up the amount of the enriched material. Purified solutions containing [Formula: see text] and [Formula: see text] were obtained within 30 min after EOB and used to produce [Formula: see text]-ATSM and [Formula: see text]–DOTA–NOC, respectively, with quality parameters suitable for human use.

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Statistical event reconstruction techniques can give better results for gamma cameras than the traditional centroid method. However, implementation of such techniques requires detailed knowledge of the photomultiplier tube light-response functions. Here we describe an iterative method which allows one to obtain the response functions from flood irradiation data without imposing strict requirements on the spatial uniformity of the event distribution. A successful application of the method for medical gamma cameras is demonstrated using both simulated and experimental data. An implementation of the iterative reconstruction technique capable of operating in real time is presented. We show that this technique can also be used for monitoring photomultiplier gain variations.