Investigation of electronic transport under mechanical strain in a molecular junction composed of a polyyne bridge connected to SWCNT electrodes.

In the present work we propose a novel treatment to investigate ballistic electron transport under mechanical strain in a 1-D molecular bridge composed of alternating simple and triple bonds (polyyne) connected between two Single-Wall Carbon Nanotube (SWCNT) electrodes. Calculations with the DFT-NEGF methodology were performed in order to analyze this system at low values of mechanical strain (compression and distension) and at equilibrium length in the presence of bias voltages applied along the longitudinal direction. The results show that, while the mechanical strain displaces the energy levels and changes the band gap in the nanotube caps, the applied bias breaks the degeneracy in the nanotube cap states and defines the electrical conductance along the system. The analysis of the PDOS suggests that the main contribution to the electrical current comes from the superposition of the nanotube cap states, which is in agreement with the transmission calculation, and this device can be employed as a transistor observed in the I-V curve.

Leprosy as a neglected disease and its stigma in the northeast of Brazil.

Hansen's disease is an infectious and degenerative chronic disease with a high potential for incapacitation. Due to the explosive epidemic of leprosy cases worldwide (especially in Brazil), the social difficulties faced by these patients are an important subject for research. This work aimed to identify the stigma experienced by these patients. The qualitative research for this study was completed at the National Reference Centre in Dermatology in Fortaleza. The study took place in northeast Brazil from September 2010 to November 2012. The research subjects included 20 people with Hansen's disease of both sexes between 20 and 70 years old. The data collection consisted of a semi-structured interview. From the discourse analysis of the participants, several changes experienced by persons affected by leprosy were noted from the empiric categories emerged. Changes occurred in the family, the receptiveness of neighbours and co-workers and the patients' social lives were experienced by the persons affected after the diagnosis of Hansen's disease. From the data obtained, it was concluded that the patients are stigmatised. Sometimes they are forced to hide from relatives, friends, neighbours and co-workers. Despite their social exclusion, they believe their isolation is justified. Leprosy is a chronic, degenerative and curable infectious illness that continues to be a serious public health problem, mainly in the poorest region of Brazil.

Wastewater irrigation of salad crops: further evidence for the evaluation of the WHO guidelines.

This paper presents the results of an experiment on salad crop irrigation with waste stabilisation pond effluents, conducted in Southeast Brazil. Over about 18 months several trials were carried out using different effluent qualities to irrigate lettuce, kale, arugula, spinach, and green pepper. Equations for predicting the bacterial quality of irrigated crops (E.coli per gram) based on the irrigation water quality (E.coli per 100 mL) were derived for low and high growing crops. The quantitative microbial risk analysis (QMRA) technique, using pathogen-ingestion scenarios based on these field data and on official statistics of vegetables consumption in Brazil, was used to estimate infection risks arising from the consumption of wastewater irrigated crops. It is inferred that irrigation with effluents complying with the WHO guidelines for unrestricted irrigation should result in salad crops acceptable for consumption.