Moisture content monitoring in industrial-scale composting systems using low-cost sensor-based machine learning techniques.

Moisture is a key aspect for proper composting, allowing greater efficiency and lower environmental impact. Low-cost real-time moisture determination methods are still a challenge in industrial composting processes. The aim of this study was to design a model of hardware and software that would allow self-adjustment of a low-cost capacitive moisture sensor. Samples of organic composts with distinct waste composition and from different composting stages were used. Machine learning techniques were applied for self-adjustment of the sensor. To validate the model, results obtained in a laboratory by the gravimetric method were used. The proposed model proved to be efficient and reliable in measuring moisture in compost, reaching a correlation coefficient of 0.9939 between the moisture content verified by gravimetric analysis and the prediction obtained by the Sensor Node.

Toxicity and physicochemical parameters of composts including distinct residues from agribusiness and slaughterhouse sludge.

Composting is useful for treatment of residues from agribusiness, but the potential toxicity of the final compost should be evaluated before its agricultural destination. The objective of this study was to evaluate the physicochemical characteristics and the toxicity of agribusiness residues using onion seeds as bioindicators. All tested treatments were composed by sludge from a swine slaughterhouse and sawdust. Besides the control, which included no additional materials, the other treatments included aviary bedding, rice husk and residue from tobacco industries as structuring materials. After 120 days of composting, for all treatments, the temperature inside the composting piles approached the environmental temperature, the physicochemical parameters indicated that the composts were stabilized and, except for the treatment including tobacco residues, that could be used for agriculture without impairing plant germination. Although the treatments including tobacco residues and rice husk showed evidence of cytotoxicity and genotoxicity at the beginning of the composting period, that was not observed for the treatment including aviary bedding. Such potential toxicity was not observed at the end of composting for any of the tested treatments.

Smoking and 2-month culture conversion during anti-tuberculosis treatment.

OBJECTIVE: To investigate risk factors for delayed sputum culture conversion to negative during anti-tuberculosis treatment, with an emphasis on smoking. DESIGN: Nested case-control study of adults with non-cavitary, culture-confirmed pulmonary tuberculosis (TB) participating in an anti-tuberculosis treatment trial in Brazil. A case of delayed culture conversion was a patient who remained culture-positive after 2 months of treatment. Odds ratios with 95% confidence intervals were calculated. RESULTS: Fifty-three cases and 240 control patients were analyzed. Smokers had three-fold greater odds of remaining culture-positive after 2 months of treatment (P = 0.007) than non-smokers, while smokers and ex-smokers who smoked >20 cigarettes a day had two-fold greater odds of remaining culture-positive after 2 months of treatment (P = 0.045). CONCLUSION: Cigarette smoking adversely affects culture conversion during anti-tuberculosis treatment. Support for smoking cessation should be considered to improve outcomes in TB control programs.

Experimental training model of pancreas transplant.

UNLABELLED: Pancreas transplant (Ptx) is the gold standard for the treatment of type I diabetes, mainly when associated with renal failure. The number of Ptx is increasing worldwide, but in developing countries, such as Brazil, the number of centers is small and transplant surgeons need to practice the technique. METHODS: For this model, 21 pancreas harvestings were performed in patient corpses after death from extra-abdominal causes, without pancreatic disease and peritoneal or systemic infection. The vessels of the grafts were prepared on the backtable according to the usual practice in humans. The pancreas was implanted in the inferior vena cava and aorta of mixed breed dogs, with 10 exocrine-bladder drainage and 11 duodenum-ileal anastomosis. RESULTS: There were anastomotic strictures of the portal vein in dogs 1 and 2. There was no arterial stricture or large bleeding. None of the animals died until the revascularization of the graft. Dogs 2, 5, and 8 died during the exocrine anastomosis. The arterial flow was initially high, but at the end of the procedure there were thromboses of small arteries. CONCLUSION: The experimental surgical technique model is feasible, repeating the stages of clinical pancreatic transplantation and allowing the training of surgeons.