Study on feeding habits of Piaractus mesopotamicus (Pacu) larvae in fish ponds

A limnological study of the artificial fish pond and an analysis of the stomach contents of pacu (Piaractus mesopotamicus) larvae of 2 to 45 days age were made for a period of 45 days to evaluate their feeding preferences. A preference for chlorophytes and rotifers were noted, while other planktonic species remained constant in the stomach contents. Some limnological variables were found to have strong influence on the feeding behavior of the pacu. A preference for feeding on smaller species in the first few days of larval development was also noted

Impact of a Tutored Theoretical-Practical Training to Develop Undergraduate Students’ Skills for the Detection of Caries Lesions: Study Protocol for a Multicenter Controlled Randomized Study

Background: Tutored laboratorial activities could be a manner of improving the competency development of students. However, its impact over conventional theoretical classes has not yet been tested. Additionally, different university contexts could influence this issue and should be explored. Objective: To assess the impact of a tutored theoretical-practical training for teaching undergraduate students to detect caries lesions as compared with theoretical teaching activities. The impact of these teaching/learning activities will be assessed in terms of efficacy, cost/benefit, retention of knowledge/acquired competences, and student acceptability. Methods: Sixteen centers (7 centers from Brazil and 9 centers from other countries throughout the world) are involved in the inclusion of subjects for this protocol. A randomized controlled study with parallel groups will be conducted. One group (control) will be exposed to a 60- to 90-minute conventional theoretical class and the other group (test) will be exposed to the same theoretical class and also a 90-minute laboratory class, including exercises and discussions based on the evaluation of a pool of images and extracted teeth. The mentioned outcomes will be evaluated immediately after the teaching activities and also in medium- and long-term analyses. To compare the long-term outcomes, students who enrolled in the university before the participating students will be interviewed for data collection and these data will be used as a control and compared with the trained group. This stage will be a nonrandomized phase of this study, nested in the main study. Appropriate statistical analysis will be performed according to the aims of this study. Variables related to the centers will also be analyzed and used to model adjustment as possible sources of variability among results. Results: This ongoing study is funded by a Brazilian national funding agency (CNPq- 400736/2014-4). We expect that the tutored theoretical-practical training will improve the undergraduate students’ performance in the detection of caries lesions and subsequent treatment decisions, mainly in terms of long-term retention of knowledge. Our hypothesis is that tutored theoretical-practical training is a more cost-effective option for teaching undergraduate students to detect caries lesions. Conclusions: If our hypothesis is confirmed, the use of laboratory training in conjunction with theoretical classes could be used as an educational strategy in Cariology to improve the development of undergraduate students’ skills in the detection of caries lesions and clinical decision-making

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time, and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space. While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes, vast areas of the tropics remain understudied. In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity, but it remains among the least known forests in America and is often underrepresented in biodiversity databases. To worsen this situation, human-induced modifications may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge, it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Dinâmica da nutrição de Metynnis cf. roosevelti Eigenmann (Characidae, Myleinae), da Lagoa Redonda, Nízia Floresta, Rio Grande do Norte, Brasil The dynamics of nutrition in Metynnis cf. roosevelti Eigenmann (Characidae, Myleinae), from Lagoa Redonda, Nízia Floresta, Rio Grande do norte, Brazil

<abstract language="eng">The time of full stomach repletion and fat condition was determined through an analysis of the average stomach repletion index, condition faclor and relative frequency of repletion for different periods of the year. Condition factor was influenced by weight gain in the stomaches, main from April to June

Cor de feijão vagem fresco e processado após aplicação de cálcio Color of fresh and processed snap bean pods after calcium application

A cor em vegetais é um dos principais atributos de qualidade observado pelo consumidor e é influenciada por características intrínsecas e de processamento. O objetivo desta investigação foi avaliar as alterações de cor de feijão vagem fresco e processado após aplicação de concentrações crescentes de cálcio via absorção radicular. O feijão vagem cultivar UEL 1 foi cultivado com aplicação de concentrações crescentes de cálcio via solução nutritiva contendo 0, 75 , 150 e 300 mL L-1 de cálcio em substrato de areia grossa. A cor das vagens ao natural e enlatadas foram avaliadas por colorimetria de três estímulos, e os resultados foram expressos no sistema Hunter. As vagens ao natural apresentaram-se mais claras e amarelas quando foi adicionado cálcio à solução nutritiva. O calor empregado no processo de enlatamento teve efeito pronunciado na redução da luminosidade e na cor verde, mesmo com o aumento na quantidade de cálcio nas vagens.<br>The color in vegetables is one of the main quality attributes observed by the consumer and it is influenced by intrinsic characteristics and canning process. This research meant to investigate the effect of increasing calcium concentrations applied to a nutrient solution on physical measurements of the color of snap bean pods.This experiment was carried out wtih the cultivar UEL 1 grown in coarse sand with nutrient solution supplied at the following levels of calcium: 0, 75, 150 and 300 mL L-1. Fresh pods were analysed for calcium content. The fresh and canned pods were evaluated for color with tristimulus colorimetry and data were expressed according to the Hunter system. The fresh pods were lighter and yellowisher when calcium was added to the nutrient solution. The heat used for the canning process had a significant effect on reducing lightness and greeness, even with the greater amounts of calcium in the pods