Enhancing Localized Pesticide Action through Plant Foliage by Silver-Cellulose Hybrid Patches.

Efficacy and efficiency of pesticide application in the field through the foliage still face many challenges. There exists a mismatch between the hydrophobic character of the leaf and the active molecule, low dispersion of the pesticides on the leaves' surface, runoff loss, and rolling down of the active molecules to the field, decreasing their efficacy and increasing their accumulation to the soil. We produced bacterial cellulose-silver nanoparticles (BC-AgNPs) hybrid patches by in situ thermal reduction under microwave irradiation in a scalable manner and obtaining AgNPs strongly anchored to the BC. Those hybrids increase the interaction of the pesticide (AgNPs) with the foliage and avoids runoff loss and rolling down of the nanoparticles. The positive antibacterial and antifungal properties were assessed in vitro against the bacteria Escherichia coli and two agro-economically relevant pathogens: the bacterium Pseudomonas syringae and the fungus Botrytis cinerea. We showed in vivo inhibition of the infection in Nicotiana benthamiana and tomato leaves, as proven by the suppression of the expression of defense molecular markers and reactive oxygen species production. The hydrogel-like character of the bacterial cellulose matrix increases the adherence to the foliage of the patches.

[Tobacco cessation. Action-stage result as a predictor of successful long-term maintenance]. / Deshabituación tabáquica. Valor del resultado en la fase de acción sobre el resultado en la fase de consolidación.

OBJECTIVE: The paucity of long-term studies makes it difficult to evaluate the sustained abstinence over time of smokers who quit. The objective of the present study was to determine to what extent the results of tobacco cessation interventions are maintained after 5 years. PATIENTS AND METHODS: This was a longitudinal prospective study of 502 smokers. The design was quasi-experimental given that therapy was allocated according to the level of the patients' nicotine dependence: routine minimum intervention for smokers with mild addiction and those not in the preparation stage, and nicotine replacement therapy for patients with moderate-to-high dependence and/or a high level of tobacco consumption. RESULTS: Of the 267 patients followed for 5 years, 29.6% quit and were still abstinent at 1 year, and 18.0% remained abstinent after 5 years. Of those who had managed to stop smoking within 2 months of starting the intervention, 47.4% were still abstinent on follow-up at 5 years while 88.1% of those who failed to quit within 2 months were still smoking 5 years later. CONCLUSIONS: The results observed during the action stage could be of use in reorienting the treatment approach, and a planned schedule of follow-up contacts could help patients maintain the abstinence achieved in the course of the intervention.