Development of a functional stack of soil microbial fuel cells to power a water treatment reactor:From the lab to field trials in North East Brazil

Worldwide over 700 million people lack access to energy and safe water. Population growth and climate change severely stress limited freshwater reserves, and the search for innovative and sustainabledecentralised water treatment technologies is more urgent than ever; especially in vulnerable areas like North East Brazil, where water access is heavily restricted. In this context, in this study the development and implementation, from the lab to the field, of a low-cost, sustainable and self-powered system for water treatment, is presented for the first time. The system consists of an array of soil microbial fuel cells (SMFCs) that powers an electrochemical reactor for water treatment. Each SMFC is characterised by a flat geometry, with the anode embedded into the soil and the cathode exposed to air. The soil acts as the electrode separator and as a source of both electroactive bacteria and organic matter. Each SMFC generates a power of 0.4 mW, which is increased up to 12.2 mW by electrically connecting 16 SMFCs in parallel, with stable performance over 140 days of operation. An upscaled system, consisting of a stack of 64 SMFCs, was subsequently installed at a primary school in Icapuí, North East of Brazil, demonstrating a treatment capacity of up to three litres of water per day when integrated with the electrochemical reactor. By demonstrating implementation from the lab to the field, our work provides an effective route for the scalability and practical application of SMFC stacks for energy generation and self-powered water purification in remote areas.</p

Brief Cognitive Behavioral Intervention in Groups in a Brazilian Assisted Reproduction Program

The study's objective was to assess the effect of a cognitive behavioral group intervention on the pregnancy rates of patients submitted to in vitro fertilization (IVF) techniques or to intracytoplasmic sperm injection (ICSI). The study was conducted on 188 patients, 93 who participated in a group of psychological intervention before the IVF and ICSI procedures and 95 patients submitted to IVF and ICSI during the same period of time, who did not participate in the intervention (control group). Clinical pregnancy was the outcome measure. Demographic and clinical variables were compared between groups in order to assess the group's homogeneity. Participants in the psychological intervention obtained a pregnancy rate of 39.8%, significantly higher than the 23.2% rate of nonparticipants (chi(2) = 6.03, p =.01, odds ratio of 22 (CI: 1.16-4.13). The data suggest that group psychological intervention before IVF and ICSI in order to control stress seems to increase the rate of success of these procedures

Assessing the diversity of whiteflies infesting cassava in Brazil.

Background. The necessity of a competent vector for transmission is a primary ecological factor driving the host range expansion of plant arthropod-borne viruses, with vectors playing an essential role in disease emergence. Cassava begomoviruses severely constrain cassava production in Africa. Curiously, begomoviruses have never been reported in cassava in South America, the center of origin for this crop. It has been hypothesized that the absence of a competent vector in cassava is the reason why begomoviruses have not emerged in South America. Methods. We performed a country-wide whitefly diversity study in cassava in Brazil. Adults and/or nymphs of whiteflies were collected from sixty-six cassava fields in the main agroecological zones of the country. A total of 1,385 individuals were genotyped based on mitochondrial cytochrome oxidase I sequences. Results. A high species richness was observed, with five previously described species and two putative new ones. The prevalent species were Tetraleurodes acaciae and Bemisia tuberculata, representing over 75% of the analyzed individuals. Although we detected, for the first time, the presence of Bemisia tabaci Middle East-Asia Minor 1 (BtMEAM1) colonizing cassava in Brazil, it was not prevalent. The species composition varied across regions, with fields in the Northeast region showing a higher diversity. These results expand our knowledge of whitefly diversity in cassava and support the hypothesis that begomovirus epidemics have not occurred in cassava in Brazil due to the absence of competent vector populations. However, they indicate an ongoing adaptation process of BtMEAM1 to cassava, increasing the likelihood of begomovirus emergence in this cro