Qualidade de sementes de arroz irrigado utilizadas em Santa Catarina no ano agrícola 2007/08

The seed is considered the most important agricultural input, mainly because it carries genetic characteristics that determine the agronomic performance and it is responsible for the success of the crop establishment. Santa Catarina is the Brazilian state that showed a major evolution in irrigated rice seed quality over the last three decades, as became evident from samplings taken from rice growers at planting time. This study aimed to evaluate the rice seed quality used by farmers in Santa Catarina state, southern Brazil. Rice seed samples (307) were collected representing all rice- -producing regions of the state, in the 2007/08 season, and a form was completed with relevant information about each sample. The samples were sent to Epagri’s seed laboratory to determine purity, germination test, vigor and red rice infestation. The survey shows that the seeds used by farmers in Santa Catarina have high quality when purity, germination and vigor are considered, but about 17% of the samples are infested with red rice.A semente é considerada o mais importante insumo agrícola, principalmente porque conduz ao campo as características genéticas determinantes do desempenho de uma cultivar, e ao mesmo tempo contribui decisivamente para o sucesso da lavoura. Santa Catarina é o Estado brasileiro que obteve a maior evolução na qualidade da semente de arroz irrigado nas três últimas décadas, demonstrada pela coleta de amostras das sementes utilizadas pelos agricultores. Este trabalho teve como objetivo realizar o levantamento da qualidade das sementes de arroz irrigado utilizadas pelos agricultores de Santa Catarina. Foram coletadas 307 amostras de sementes em todas as regiões produtoras de arroz irrigado no Estado no ano agrícola 2007/08. Por ocasião da coleta, utilizou-se um questionário para obter informações adicionais sobre a semente e a lavoura de cada agricultor. Em laboratório, foram realizadas as seguintes avaliações: análise de pureza, teste de germinação, teste de vigor e ocorrência de arroz-vermelho. Conclui-se que as sementes utilizadas pelos agricultores de Santa Catarina apresentaram alta qualidade, considerando pureza, germinação e vigor, porém 17% das amostras apresentam infestação por arroz-vermelho

As atuais tendências das pesquisas brasileiras em ensino de química: um estado do conhecimento de periódicos específicos

This paper presents a state of knowledge study on the current research trends in the area of Chemistry Teaching in Brazil. Thus, the objective was to identify and understand the investigative approaches, aiming to contribute to the understanding of educators and researchers about the particularities of the area. To this end, articles published in two Brazilian journals specific to Chemistry Teaching were reviewed in the last five years, from 2015 to 2019. The analysis process was based on the Content Analysis method and, thus, the research assumed a qualitative character associated with quantitative indicators, since these indicators provided a basis. The results showed that research on approaches and means for teaching, as well as the subjects involved in teaching and learning processes, are often present in Chemistry Teaching. In the case of teachers and undergraduates, studies concerning the aspects of initial and continuing training are predominated. Regarding investigations focusing on students, it was noted that the learning and meaning processes stood out as an object of study. However, it is concluded that the main trend is the research on educational actions and instruments, with an emphasis on themes involving social and environmental issues.Este artículo presenta un estudio de de tipo estado del arte sobre las tendencias actuales de investigación en el área de la Enseñanza de la Química en Brasil. El objetivo fue identificar y comprender los enfoques investigativos, con el objetivo de contribuir a la comprensión de los educadores e investigadores sobre las particularidades del área. Para ello, se revisaron artículos publicados en dos revistas brasileñas específicas de Enseñanza de la Química en los últimos cinco años, de 2015 a 2019. El proceso de análisis se basó en el método de Análisis de Contenido y, así, la investigación asumió un carácter cualitativo asociado a indicadores cuantitativos, ya que estos indicadores sirvieron de base. Los resultados mostraron que las investigaciones sobre enfoques y medios para la enseñanza, tanto como las materias involucradas en los procesos de enseñanza y aprendizaje, suelen estar presentes en la Enseñanza de la Química. En el caso de profesores y estudiantes de pregrado, predominan los estudios sobre los aspectos de la formación inicial y continua. En cuanto a las investigaciones centradas en los estudiantes, se observó que los procesos de aprendizaje y construcción de significados se destacan como objetos de estudio. Sin embargo, se concluye que la principal tendencia es la investigación sobre acciones e instrumentos educativos, con énfasis en temas relacionados con la problemática social y ambiental.Este trabalho apresenta um estudo do tipo estado do conhecimento sobre as atuais tendências das pesquisas da área Ensino de Química no Brasil. Assim, objetivou-se identificar e compreender os enfoques das investigações, visando contribuir com o entendimento de educadores e pesquisadores acerca das particularidades da área. Para tanto, revisaram-se artigos publicados em dois periódicos brasileiros específicos do Ensino de Química, nos últimos cinco anos, de 2015 a 2019. O processo de análise foi fundamentado no método Análise de Conteúdo e, deste modo, a pesquisa assumiu um caráter qualitativo associado a indicadores quantitativos, visto que estes indicadores forneceram embasamento. Os resultados demonstraram que pesquisas sobre as abordagens e os meios para o ensino, bem como os sujeitos envolvidos nos processos de ensino e aprendizagem, estão frequentemente presentes no Ensino de Química. Tratando-se de docentes e licenciandos, predominam-se estudos referentes aos aspectos da formação inicial e continuada. Em relação às investigações com foco nos estudantes, notou-se que os processos de aprendizagem e de significação se destacaram como objeto de estudo. Contudo, conclui-se que a principal tendência são as pesquisas sobre ações e instrumentos didáticos, com ênfase nas temáticas envolvendo questões sociais e ambientais.

COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study

Background: The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms. Methods: International, prospective observational study of 60 109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms. Results: ‘Typical’ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (≤ 18 years: 69, 48, 23; 85%), older adults (≥ 70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each P < 0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country. Interpretation: This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men

O uso do smartphone no desenvolvimento de modelos mentais dos alunos no ensino de Química: aplicativos de simulação virtual e realidade aumentada

Neste artigo, com o intuito de se trabalhar conceitos do ensino de atomística e periodicidade, aplicaram-se atividades que utilizavam recursos tecnológicos para smartphones, como aplicativos de simulação virtual e realidade aumentada. A pesquisa foi desenvolvida com alunos do terceiro ano do ensino médio de uma escola pública, localizada em Presidente Prudente – SP (Brasil). Adotou-se, como referencial, a teoria de modelos mentais de Johnson-Laird (1983), na qual modelos mentais são definidos como construções internas, que são análogas ao objeto ou fenômeno que está sendo representado. Desta forma, teve-se como objetivo analisar e, possivelmente, aprimorar os modelos mentais dos alunos sobre a concepção de elemento químico, bem como propriedades relacionadas às estruturas atômicas. Notou-se que, por meio das atividades realizadas, os alunos apresentaram melhorias significativas nos modelos mentais expressos sobre os conceitos trabalhados, visto que, inicialmente, a maioria apresentou ideias simplistas ou, até mesmo, equivocadas, porém, ao final do trabalho, surgiram modelos mentais mais sofisticados, ou seja, com elementos (tokens) mais próximos aos modelos científicos. Além disso, trabalhar com Tecnologias Digitais de Informação e Comunicação (TDIC) e jogos didáticos propiciou aulas mais dinâmicas, uma vez que os alunos trabalharam em grupos e participaram de forma ativa

Ammonia emissions from dairy cows grazing an annual temperate pasture with or without energetic supplementation

Ammonia (NH3) emissions from animal excretions has been a concern in grazing dairy systems, and is dependent of the proportion of total urinary and fecal nitrogen (N) lost as NH3. The aim of this study was to assess NH3 emissions from excreta of dairy cows grazing an annual temperate pasture (A. strigosa Schum + L. multiflorum Lam.) exclusively or receiving energetic supplementation. Treatments were grazing without supplementation, grazing + 4.2 kg DM corn silage and grazing + 3.2 kg DM ground corn. Supplements were calculated in order to provide the same amount of metabolisable energy. Feces and urine were sampled from four cows of each treatment during one day, at 7:30 and 16:30 h. One hundred and thirty g of feces and 80 mL of urine from each treatment plus a control without excreta were assigned into the pasture area, considering a randomized complete block design with three replications. The NH3 was captured by a semi-open chamber (10 cm diameter) containing a foam strip soaked with a solution of H2SO4 1M + 2% glycerin. The foam strips were replaced 2, 4, 7, 10, 13, 17, 21 and 25 days after distribution of excreta into the pasture, and ammonium concentration was performed by steam distillation. The amount of N recovered was multiplied by a factor of 1.74 calculated from the N-NH3 recovery (1/0.63) of this technic. The fraction of excreta N volatilized as NH3 was calculated by the ratio between the N volatilized from excreta corrected to the volatilization from the control. The fraction of urinary N lost as NH3 was similar between treatments, averaging 19.2%, but the fraction of fecal N lost as NH3 decreased from 4.6% in no supplemented cows to 2.4 and 0.6% in animals supplemented with corn silage and corn ground, respectively. Total excreta (urine + feces) NH3-N emissions factors were similar between treatments, averaging 22%. Supplementing dairy cows grazing an annual temperate pasture with corn silage or corn ground may mitigate NH3 emissions factors from feces but not from urine or total excreta. The amount of N excreted by these animals will be considered to obtain the real amounts of NH3-N emissions in each treatment

From abortion-inducing medications to Zika Virus Syndrome: 27 years experience of the First Teratogen Information Service in Latin America

Abstract In 1990, the first Teratogen Information Service in Brazil (SIAT) was implemented in the Medical Genetics Service at Hospital de Clinicas de Porto Alegre. SIAT is a free-to-use information service both to health professionals and the general population, especially to women who are pregnant or planning pregnancy. The main objective of this paper is to present the activities of SIAT in its initial years (1990-2006), compared to those in the last decade (2007-2017). In addition we review the scientific contribution of SIAT in the field of human teratogenesis. Since 1990, SIAT received 10,533 calls. Use of medications were the main reason for concern, accounting for 74% of all questions, followed by other chemical exposures (occupational, cosmetics, environmental), and maternal infectious diseases. Among its main contributions to scientific knowledge was the collaboration for the identification of two new human teratogens: misoprostol in the 1990s and Zika virus in 2015/16. In conclusion, SIAT is still evolving, as is the Medical Genetics Service that hosts it. Through its 27 years of existence more than 300 undergraduate and graduate students have rotated at SIAT. Presently, SIAT is expanding the research to experimental teratogenesis and to investigation of molecular mechanisms of teratogens

From abortion-inducing medications to Zika Virus Syndrome : 27 years experience of the First Teratogen Information Service in Latin America

In 1990, the first Teratogen Information Service in Brazil (SIAT) was implemented in the Medical Genetics Service at Hospital de Clinicas de Porto Alegre. SIAT is a free-to-use information service both to health professionals and the general population, especially to women who are pregnant or planning pregnancy. The main objective of this paper is to present the activities of SIAT in its initial years (1990-2006), compared to those in the last decade (2007-2017). In addition we review the scientific contribution of SIAT in the field of human teratogenesis. Since 1990, SIAT received 10,533 calls. Use of medications were the main reason for concern, accounting for 74% of all questions, followed by other chemical exposures (occupational, cosmetics, environmental), and maternal infectious diseases. Among its main contributions to scientific knowledge was the collaboration for the identification of two new human teratogens: misoprostol in the 1990s and Zika virus in 2015/16. In conclusion, SIAT is still evolving, as is the Medical Genetics Service that hosts it. Through its 27 years of existence more than 300 undergraduate and graduate students have rotated at SIAT. Presently, SIAT is expanding the research to experimental teratogenesis and to investigation of molecular mechanisms of teratogens

From abortion-inducing medications to Zika Virus Syndrome : 27 years experience of the First Teratogen Information Service in Latin America

In 1990, the first Teratogen Information Service in Brazil (SIAT) was implemented in the Medical Genetics Service at Hospital de Clinicas de Porto Alegre. SIAT is a free-to-use information service both to health professionals and the general population, especially to women who are pregnant or planning pregnancy. The main objective of this paper is to present the activities of SIAT in its initial years (1990-2006), compared to those in the last decade (2007-2017). In addition we review the scientific contribution of SIAT in the field of human teratogenesis. Since 1990, SIAT received 10,533 calls. Use of medications were the main reason for concern, accounting for 74% of all questions, followed by other chemical exposures (occupational, cosmetics, environmental), and maternal infectious diseases. Among its main contributions to scientific knowledge was the collaboration for the identification of two new human teratogens: misoprostol in the 1990s and Zika virus in 2015/16. In conclusion, SIAT is still evolving, as is the Medical Genetics Service that hosts it. Through its 27 years of existence more than 300 undergraduate and graduate students have rotated at SIAT. Presently, SIAT is expanding the research to experimental teratogenesis and to investigation of molecular mechanisms of teratogens