Estudo das causas de retenção e evasão na disciplina de química geral no curso de física do IFCE – Campus Tianguá

The search for academic excellence has emphasized the importance of several actions seeking positive impacts in the educational area. In this context, it is known that, in an undergraduate program such as Physics, it is difficult for undergraduate students to complete their training within the scheduled period, and they may also look for other paths or opportunities. Evasion and retention in undergraduate programs are complex phenomena resulting from different motivations and that need to be studied, seeking possible failures in the teaching and learning processes. This work analyzed, in a non-interventional way, these phenomena in the discipline of General Chemistry, seeking to identify possible causes and strategies for their reduction. Problems such as infrastructure, school transport, hosting of students, methodology, economic conditions, lack of affinity with the course and basic training are some of the factors described with a greater negative emphasis. The literature reports that, in some cases, actions that increase the student's bond with the institution and that also enable improvement in teaching and student assistance are fundamental and contribute to reducing student evasion and retention.A busca pela excelência acadêmica tem enfatizado a importância de diversas ações buscando impactos positivos na área educacional. Nesse contexto, é conhecido que, num curso como o de licenciatura em Física, dificilmente os licenciandos conseguem concluir sua formação no prazo previsto, podendo ainda procurar outros caminhos ou oportunidades. A evasão e a retenção em cursos de graduação são fenômenos complexos decorrentes de diferentes motivações e que necessitam ser estudados, buscando assim, possíveis falhas nos processos de ensino e aprendizagem. Este trabalho analisou, de forma não interventiva, estes fenômenos na disciplina de Química Geral, buscando identificar possíveis causas e estratégias para redução dos mesmos. Problemas como infraestrutura, transporte escolar, acolhimento dos estudantes, metodologia, condições econômicas, falta de afinidade com o curso e formação básica são alguns dos fatores descritos com um maior destaque negativo. A literatura relata que, em alguns casos, ações que aumentem o vínculo do estudante com a instituição, e que propiciem melhorias do ensino e de assistência estudantil são fundamentais e contribuintes para a redução da evasão e retenção dos estudantes

Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adults

Background Underweight and obesity are associated with adverse health outcomes throughout the life course. We estimated the individual and combined prevalence of underweight or thinness and obesity, and their changes, from 1990 to 2022 for adults and school-aged children and adolescents in 200 countries and territories. Methods We used data from 3663 population-based studies with 222 million participants that measured height and weight in representative samples of the general population. We used a Bayesian hierarchical model to estimate trends in the prevalence of different BMI categories, separately for adults (age ≥20 years) and school-aged children and adolescents (age 5–19 years), from 1990 to 2022 for 200 countries and territories. For adults, we report the individual and combined prevalence of underweight (BMI 2 SD above the median). Findings From 1990 to 2022, the combined prevalence of underweight and obesity in adults decreased in 11 countries (6%) for women and 17 (9%) for men with a posterior probability of at least 0·80 that the observed changes were true decreases. The combined prevalence increased in 162 countries (81%) for women and 140 countries (70%) for men with a posterior probability of at least 0·80. In 2022, the combined prevalence of underweight and obesity was highest in island nations in the Caribbean and Polynesia and Micronesia, and countries in the Middle East and north Africa. Obesity prevalence was higher than underweight with posterior probability of at least 0·80 in 177 countries (89%) for women and 145 (73%) for men in 2022, whereas the converse was true in 16 countries (8%) for women, and 39 (20%) for men. From 1990 to 2022, the combined prevalence of thinness and obesity decreased among girls in five countries (3%) and among boys in 15 countries (8%) with a posterior probability of at least 0·80, and increased among girls in 140 countries (70%) and boys in 137 countries (69%) with a posterior probability of at least 0·80. The countries with highest combined prevalence of thinness and obesity in school-aged children and adolescents in 2022 were in Polynesia and Micronesia and the Caribbean for both sexes, and Chile and Qatar for boys. Combined prevalence was also high in some countries in south Asia, such as India and Pakistan, where thinness remained prevalent despite having declined. In 2022, obesity in school-aged children and adolescents was more prevalent than thinness with a posterior probability of at least 0·80 among girls in 133 countries (67%) and boys in 125 countries (63%), whereas the converse was true in 35 countries (18%) and 42 countries (21%), respectively. In almost all countries for both adults and school-aged children and adolescents, the increases in double burden were driven by increases in obesity, and decreases in double burden by declining https://researchonline.ljmu.ac.uk/images/research_banner_face_lab_290.jpgunderweight or thinness. Interpretation The combined burden of underweight and obesity has increased in most countries, driven by an increase in obesity, while underweight and thinness remain prevalent in south Asia and parts of Africa. A healthy nutrition transition that enhances access to nutritious foods is needed to address the remaining burden of underweight while curbing and reversing the increase in obesity

Potentially evaluation chemical and biological of Tephrosia toxicaria Pers. (Fabaceae)

Tephrosia toxicaria Pers. (Fabaceae) popularmente conhecida como âtimbà de caienaâ, à utilizada na lavoura como defensivo agrÃcola e na pesca para paralisar peixes, devido sua atividade ictiotÃxica. Este trabalho relata o estudo quÃmico de T. toxicaria e avaliaÃÃo das atividades antioxidante e larvicida sobre Aedes aegypti. O estudo quÃmico permitiu o isolamento de dez flavonoides (TTP-1 â luteolina, TTP-3 â 6a,12a-desidro- a-toxicarol, TTP-4 â a-toxicarol, TTP-5 â obovatina, TTP-6 â deguelina, TTP-8 â villosinol, TTP-9 â 12a-hidroxi-a-toxicarol, TTP-10 â sumatrol, TTP-11 â 12a-hidroxirotenona e TTP-12 â tephrosina) â sendo oito deles rotenoides â uma cromona (TTP-13 â 6,7-dimetoxicromona) e a mistura dos esteroides sitosterol e estigmasterol, nas suas formas simples e glicosiladas. Ensaios larvicidas e antioxidantes foram realizados com diversos extratos, partiÃÃes e com alguns dos metabÃlitos secundÃrios isolados. Devido à presenÃa de rotenoides, compostos que tÃm sido utilizados no controle de pragas agrÃcolas desde o sÃculo XIX, o estudo de T. toxicaria se mostrou bastante promissor, com diversas amostras ativas, apresentando atividade comparÃvel à da rotenona, composto utilizado como padrÃo positivo do ensaio larvicida. Os resultados dos ensaios antioxidantes sugerem T. toxicaria como uma fonte potencial desses agentes, provavelmente devido à presenÃa de flavonoides. As substÃncias isoladas foram identificadas por mÃtodos espectromÃtricos e espectroscÃpicos (IV, EM, RMN 1H e RMN 13C), incluindo RMN bidimensional (HMBC, HSQC e COSY) e por comparaÃÃo com dados da literatura.Tephrosia toxicaria Pers. (Fabaceae) popularly known as "timbà de caiena" is used as pesticide and fishing poison, because its activity icthyotoxic. This work reports the chemical study of T. toxicaria and its larvicidal and antioxidant activities evaluation. Phytochemical investigation led to the isolation of ten flavonoids (TTP-1 â luteolin, TTP-3 â 6a,12a-dehydro-a-toxicarol, TTP-4 â a-toxicarol, TTP-5 â obovatin, TTP-6 â deguelin, TTP-8 â villosinol, TTP-9 â 12a-hydroxy-a-toxicarol, TTP-10 â sumatrol, TTP-11â12a-hydroxyrotenone and TTP-12 â tephrosin) â eight of them rotenoids â one cromone (TTP-13 â 6,7-dimethoxychromone) and the mixture of steroids sitosterol and stigmasterol, in their simple forms and glycosylated. Antioxidant and larvicidal assays were performed with several extracts, partitions and with some of the secondary metabolities isolated. Due to the presence of rotenoids, compounds have been used to control in agricultural pest since the XIX century, the study of T. toxicaria was quite promising, with several active extracts, with activity comparable to that of rotenone, compound used as a positive test. Its antioxidant activity tests shown T. toxicaria as a potential source of these agents, probably due to the presence of flavonoids, compounds characteristic for presenting various types of biological activities. The substances were isolated and its structures determined by spectroscopic and spectrometric methods (IR, EM, 1H NMR and 13C NMR), including two-dimensional NMR (HMBC, HSQC and COSY) and by comparison with literature data

Estudo químico e biológico de Tephrosia toxicaria Pers. Chemical and biological study of the Tephrosia toxicaria Pers.

<abstract language="eng">The ethanol extracts from leaves, stems, pods and roots were assayed against the 3rd instar Aedes aegypti larvae and the highest activity was observed in the roots extracts (LC50 47.86 ppm). This extract was submitted to partition with hexane, chloroform, ethyl acetate and methanol. The respective fractions were bioassayed and the best larvicidal activities were identified in the hexane (LC50 23.99 ppm) and chloroform (LC50 13.80 ppm) fractions. Antioxidant activity (DDPH method) was observed in the ethanol extract (IC50 276 µg/mL) from roots of T. toxicaria. Fractions from this extract were also tested and the highest antioxidant activity (IC50 89 µg/mL) was found in the methanol fraction. The flavonoids iso-obovatin (1), obovatin (2), 6a,12a-dehydro-&#946;-toxicarol (3), 6a,12a-dehydro-&#945;-toxicarol (4) and &#945;-toxicarol (5) were isolated and bioassayed against A. aegypti. The flavonoid 5 showed the best larvicidal activity (LC50 24.55 ppm). The antioxidant activity of 2 was investigated and showed IC50 3.370 µg/mL. The antioxidant and larvicidal activities of Tephrosia toxicaria are reported for the first time

Chemical composition and larvicidal activity of Rollinia leptopetala (Annonaceae)

The aim of present study was to describe the chemical composition of the essential oils from the leaf and stem of Rollinia leptopetala R. E. Fries (Annonaceae) and to evaluate the larvicidal activities of these essential oils, of the methanol extract from roots of this plant and of the oxoaporphine alkaloid, liriodenine (1) against the third-instar of Aedes aegypti larvae. The methanol extract from the roots showed larvicidal activity with LC50 64.6 ± 1.5 ppm. Higher activity was observed for the isolated alkaloid liriodenine (1), LC50 3.6 ± 0.4 ppm. The essential oils from the leaves and stems, also exhibited larvicidal activity with LC50 104.7 ± 0.2 and 34.7 ± 0.3 ppm, respectively. These results suggest R. leptopetala as a source of natural larvicidal compounds. This is the first report about the chemical composition and larvicidal activity of the leaf and stem essential oils of R. leptopetala

Rotenoids from Tephrosia toxicaria with larvicidal activity against Aedes aegypti, the main vector of dengue fever

In the search for new larvicides from plants, we have investigated the potential activity of the rotenoids deguelin (1), 12a-hydroxy-α-toxicarol (2) and tephrosin (3), isolated from the bioactive ethanol extract of roots of Tephrosia toxicaria Pers., against Aedes aegypti, the main vector of dengue. The absolute configuration of these compounds was determined by circular dichroism (CD) spectra. The LC50 values of the compounds evaluated justify the potential of T. toxicaria as a new natural larvicide