Identificación de dificultades conceptuales y procedimentales de alumnos y docentes de EGB sobre la flotación de los cuerpos

En este trabajo analizamos las dificultades conceptuales y procedimentales de alumnos de EGB 3 (edad promedio 14 años), relacionadas con la flotación de los cuerpos. Éste es un estudio exploratorio que se complementa con una indagación realizada a docentes del mismo nivel educativo, en la cual comprobamos que muchos de los problemas detectados en los estudiantes también se presentan en los docentes. Además, examinamos los textos consultados por docentes y alumnos, encontrando algunas coincidencias con los inconvenientes hallados.Palabras claves: flotación; dificultades; alumnos; docentes.Identification of conceptual and procedural difficulties of students and teachers of EGB on the floating of bodiesIn this paper we analyze the conceptual and procedural difficulties of students of EGB 3 (average age 14 years), related with the floating of bodies. This is an exploratory study which is supplemented with an inquiry made to teachers of the same educational level, in which we proved that many of the problems detected in the students are also shown by the teachers. Besides, we examined the texts used by teachers and students, finding some coincidences with the inconveniences found.Key words: floating; difficulties; students; teachers

Sensibilidade a carrapaticidas em populações de Rhipicephalusmicroplus da região sudeste do país.

Rhipicephalus microplus é considerado um grande entrave para a pecuária leiteira e de corte no mundo, uma vez que seu controle através do uso de carrapaticida tem se tornado uma difícil tarefa devido à seleção de populações resistentes

Atividade carrapaticida do alfa-bisabolol sobre populações de Rhipicephalus microplus (acari: ixodidae) com diferentes perfis de resistência.

O presente estudo teve como objetivo investigar a atividade acaricida do alfa-bisabolol sobre populações de Rhipicephalus microplus, com diferentes perfis de resistência.Evento online

Unraveling the Enzymatic Basis of Wine "Flavorome": A Phylo-Functional Study of Wine Related Yeast Species

Non-Saccharomyces yeasts are a heterogeneous microbial group involved in the early stages of wine fermentation. The high enzymatic potential of these yeasts makes them a useful tool for increasing the final organoleptic characteristics of wines in spite of their low fermentative power. Their physiology and contribution to wine quality are still poorly understood, with most current knowledge being acquired empirically and in most cases based in single species and strains. This work analyzed the metabolic potential of 770 yeast isolates from different enological origins and representing 15 different species, by studying their production of enzymes of enological interest and linking phylogenetic and enzymatic data. The isolates were screened for glycosidase enzymes related to terpene aroma release, the β-lyase activity responsible for the release of volatile thiols, and sulfite reductase. Apart from these aroma-related activities, protease, polygalacturonase and cellulase activities were also studied in the entire yeast collection, being related to the improvement of different technological and sensorial features of wines. In this context, and in terms of abundance, two different groups were established, with α-L-arabinofuranosidase, polygalacturonase and cellulase being the less abundant activities. By contrast, β-glucosidase and protease activities were widespread in the yeast collection studied. A classical phylogenetic study involving the partial sequencing of 26S rDNA was conducted in conjunction with the enzymatic profiles of the 770 yeast isolates for further typing, complementing the phylogenetic relationships established by using 26S rDNA. This has rendered it possible to foresee the contribution different yeast species make to wine quality and their potential applicability as pure inocula, establishing species-specific behavior. These consistent results allowed us to design future targeted studies on the impact different non-Saccharomyces yeast species have on wine quality, understanding intra and interspecific enzymatic odds and, therefore, aiming to predict the most suitable application for the current non-Saccharomyces strains, as well as the potential future applications of new strains. This work therefore contributes to a better understanding of the concept of wine microbiome and its potential consequences for wine quality, as well as to the knowledge of non-Saccharomyces yeasts for their use in the wine industry.The funding for the research described in this paper was provided by Agrovin S.A, within the framework of the project IDI-20130192 (Centre for Industrial Technological Development-CDTI, Spain) and by Pago de Carraovejas, within the framework of the project IDI-20140448 (Centre for Industrial Technological Development-CDTI, Spain). We thank Dr. Cristina Gutiérrez for her technical support, and Rocío Ramírez for reading the paper and contributing to its final version.S

AgroTutor: A Mobile Phone Application Supporting Agricultural Sustainable Intensification

Traditional agricultural extension services rely on extension workers, especially in countries with large agricultural areas. In order to increase adoption of sustainable agriculture, the recommendations given by such services must be adapted to local conditions and be provided in a timely manner. The AgroTutor mobile application was built to provide highly specific and timely agricultural recommendations to farmers across Mexico and complement the work of extension agents. At the same time, AgroTutor provides direct contributions to the United Nations Sustainable Development Goals, either by advancing their implementation or providing local data systems to measure and monitor specific indicators such as the proportion of agricultural area under productive and sustainable agriculture. The application is freely available and allows farmers to geo-locate and register plots and the crops grown there, using the phone’s in-built GPS, or alternatively, on top of very high-resolution imagery. Once a crop and some basic data such as planting date and cultivar type have been registered, the app provides targeted information such as weather, potential and historical yield, financial benchmarking information, data-driven recommendations as well as commodity price forecasts. Farmers are also encouraged to contribute in-situ information, e.g., soils, management, and yield data. The information can then be used by crop models, which, in turn, would send tailored results back to the farmers. Initial feedback from farmers and extension agents has already improved some of the app’s characteristics. More enhancements are planned for inclusion in the future to increase the app’s function as a decision support tool

AgroTutor: A Mobile Phone Application Supporting Sustainable Agricultural Intensification

Traditional agricultural extension services rely on extension workers, especially in countries with large agricultural areas. In order to increase adoption of sustainable agriculture, the recommendations given by such services must be adapted to local conditions and be provided in a timely manner. The AgroTutor mobile application was built to provide highly specific and timely agricultural recommendations to farmers across Mexico and complement the work of extension agents. At the same time, AgroTutor provides direct contributions to the United Nations Sustainable Development Goals, either by advancing their implementation or providing local data systems to measure and monitor specific indicators such as the proportion of agricultural area under productive and sustainable agriculture. The application is freely available and allows farmers to geo-locate and register plots and the crops grown there, using the phone’s built-in GPS, or alternatively, on top of very high-resolution imagery. Once a crop and some basic data such as planting date and cultivar type have been registered, the application provides targeted information such as weather, potential and historical yield, financial benchmarking information, data-driven recommendations, and commodity price forecasts. Farmers are also encouraged to contribute in-situ information, e.g., soils, management, and yield data. The information can then be used by crop models, which, in turn, send tailored results back to the farmers. Initial feedback from farmers and extension agents has already improved some of the application’s characteristics. More enhancements are planned for inclusion in the future to increase the application’s function as a decision support tool

Reproduction, development and habits of the large turkey louse Chelopistes meleagridis (Phthiraptera: Ischnocera) under laboratory conditions

The bionomy of Chelopistes meleagridis off the host was observed with the aim of better understanding the aspects of this species' life cycle. For this purpose, C. meleagridisadults were collected and maintained under controlled conditions to reproduce (35°C and RH > 80%), with turkey feathers as the food source. From the offspring of these lice, the development of 150 individuals was observed from the egg to the adult phase. These eggs were divided into two groups of 75 each. After hatching, one group was given a diet composed of feathers while the other received feathers plus skin of the host turkey (Meleagris gallopavo). The “feather + skin” diet resulted in the greatest number of adults, so this diet was given to the next generation of lice reared in vitro, starting from the first instar, to observe their fertility, fecundity and longevity. High reproduction rates were found in relation to other lice of the Ischnocera sub-order, particularly the number of eggs per day and number of eggs produced per female over the lifetime (means of 2.54 and 26.61 eggs, respectively, for wild females and 2.11 and 29.33 eggs for laboratory-reared females). The inclusion of skin in the diet was a determining factor for development to the adult stage, since 48% of the lice fed this diet reached that stage, versus 1.3% that reached maturity fed only with feathers. The development time of the males and females was similar (mean of 29.38 days), without any difference in the sexual proportion of the adults