Local botanical knowledge of native food plants in the semiarid region of Brazil.

BACKGROUND: This study aimed to investigate the local botanical knowledge of native food plants in three rural communities, located in the semiarid region of Paraíba State, Brazil, verifying possibilities of differences of knowledge among communities and between men and women. METHODS: Semi-structured interviews about native plant knowledge and use were conducted with all householders in each community, totaling 117 informants. The species similarity among the communities of Pau D'Arco, Várzea Alegre, and Barroquinha was compared with Jaccard index, and the use value index (UVgeneral, UVcurrent, UVpotential) was used to determine the most important species. The Kruskal-Wallis test was used to compare the use values among communities and genders. The consensus factor among the informants was calculated according to the uses cited, and the Wilcoxon test was used to compare the use values between men and women. RESULTS: We recorded 9 species belonging to 8 genera and 8 families in Várzea Alegre; 10 species, 9 genera, and 9 families in Barroquinha; and 7 species, 7 genera and 7 families in Pau D'Arco. Spondias tuberosa Arruda (Anacardiaceae) in Várzea Alegre, Spondias sp. (Anacardiaceae) in Barroquinha, and Ximenia americana L. (Olacaceae) in Pau D'Arco were the most prominent species. Preparation methods are slightly different in the three communities, and there is low similarity about species use among the communities. Regarding gender, the analysis of use value among the communities evidenced significant differences only for UVgeneral among women, specifically between Barroquinha and Pau D'Arco. For men and women within each community, there is a difference only for UVpotential in Barroquinha. CONCLUSION: This study showed that the residents of the three rural communities have limited knowledge of native food plants found in their communities, but they know where to find them, which parts they may use and how to consume them. The fact is that men know plants that are more distant from the residences and women know those that are next to them.

Use and knowledge of Cactaceae in Northeastern Brazil.

BACKGROUND: This study aimed to record the use, and knowledge that residents from São Francisco community (Paraiba, Brazil) have regarding the Cactaceae. METHODS: Semi-structured interviews were carried out with 118 informants; 50 men and 68 women. The cacti cited in this study were organised into use categories and use values were calculated. Differences in the values applied to species and use categories by men and women were compared via a G test (Williams). RESULTS: The nine species identified were: Cereus jamacaru DC., Melocactus bahiensis (Brtitton & Rose) Luetzelb., Nopalea cochenillifera (L.) Salm-Dyck., Opuntia ficus indica (L.) Mill, Opuntia stricta (Haw.) Haw., Pilosocereus gounellei (F.A.C. Weber) Byles & Rowley, Pilosocereus pachycladus F. Ritter, Tacinga inamoena (K. Schum) N.P. Taylor & Stuppy, Tacinga palmadora (Britton & Rose) N.P. Taylor & Stuppy. In total, 1,129 use citations were recorded, divided into 11 categories. The use value categories with the highest scores were forage (0.42), food (0.30) and construction (building) (0.25). P. pachycladus showed the greatest use value, versatility and number of plant parts used. CONCLUSION: The survey showed that the Cactaceae is extremely important for several uses and categories attributed to different species. Apart from contributing to the ethnobotanical knowledge of the Cactaceae, another important focus of this study was to reinforce the necessity for further studies that record the traditional knowledge about this plant family, which has been lost in younger generations.

Digital controller design considering hardware constraints: application in a paraplegic patient

INTRODUCTION: A methodology was developed for implementing closed-loop control algorithms and for evaluating the behavior of a system, considering certain component restrictions used in laboratory implementation. METHODS: Mathematical functions representing a model of the biological system were used for knee extension/flexion movements. A Proportional Integral Derivative (PID) controller and another one using the root locus method were designed to control a patient’s leg position by applying functional electrical stimulation (FES). The controllers were simulated in Matlab and ISIS Proteus. After the simulations were performed, the codes were embedded in a microcontroller, and tests were conducted on a paraplegic volunteer. To the best of the authors’ knowledge, this is the first time that ISIS Proteus software resources have been used prior to implementing a closed-loop system designed to control the leg position of patients. RESULTS:This method obviates the application of initial controller tests directly to patients. The response obtained in the experiment with a paraplegic patient complied with the specifications set in terms of the steady-state error, the settling time, and the percentage overshoot. The proposed procedure was successfully applied for the implementation of a controller used to control the leg position of a paraplegic person by electrical muscle stimulation. CONCLUSION:The methodology presented in this manuscript can contribute to the implementation of analog and digital controllers because hardware limitations are typically not taken into account in the design of controllers.