Abstract Introduction: The global incidence of sickle cell disease (SCD) is approximately 300.000 births per year, and the condition is associated with significant morbidity and mortality in pediatric age. This study aimed to describe the sociodemographic and clinical characteristics of children up to five years of age with SCD in a Portuguese center. Methods: This was a descriptive retrospective study of children aged until five years with a diagnosis of SCD and hematologic follow-up in a level II Portuguese hospital between January 2010 and December 2019. Results: Eighty-six patients were included, mostly of African descendent and homozygotic for hemoglobin S. The median age at diagnosis was five months, obtained through neonatal screening in 44.2%, in the context of hospitalization in 34.9%, and in ambulatory observation in 17.4% of patients. A total of 96.5% of cases were compliant with the Portuguese National Vaccination (PNV) Program, and 48.8% completed the extra-PNV scheme. All patients were under folic acid supplementation, 98% were under amoxicillin prophylaxis, and 6.9% were under hydroxycarbamide. Transcranial Doppler was conducted in 68.6% of patients and was altered in only one, echocardiogram was performed in 72.1% of patients and showed left ventricle dilatation in 21%, and overnight polysomnography was performed in 24.4% of patients and revealed obstructive sleep apnea in 95.2%. Each child had an average of four hospitalizations during the study period, with the most common diagnosis being vaso-occlusive crisis in 38.3%, followed by fever of unknow origin in 23.4%, upper airway infection in 17.8%, bacterial pneumonia and splenic sequestration in 10.7% each, and worsening anemia in 9.5%. Discussion: Given the chronicity of SCD and the multiplicity of associated comorbidities, it is essential to reinforce the importance of multidisciplinary follow-up and family engagement in treatment.

Resumo Introdução: A doença das células falciformes (DCF) ocorre em cerca de 300.000 nascimentos por ano a nível mundial, associando-se a morbimortalidade significativa em idade pediátrica. Este estudo pretendeu fazer a caracterização sociodemográfica e clínica da população até aos cinco anos com DCF seguida num centro português. Métodos: Estudo retrospetivo descritivo de crianças até aos cinco anos de idade com DCF e seguimento em consulta de Hematologia pediátrica num hospital português de nível II entre 2010 e 2019. Resultados: Foram incluídas 86 crianças, maioritariamente de ascendência africana e homozigóticos para a hemoglobina S. A mediana de idades ao diagnóstico foi de cinco meses, tendo as idades sido obtidas obtida através de rastreio neonatal em 44,2% dos casos, em contexto de internamento em 34,9% e em contexto de consulta em 17,4%. O Programa Nacional de Vacinação (PNV) foi cumprido em 96,5% e 48,8% realizaram o esquema vacinal extra-PNV recomendado. Todos os doentes estavam a receber medicação com ácido fólico, 98% estava a receber amoxicilina em regime profilático e 6,9% hidroxicarbamida. No total, 68,6% efetuaram Eco-Doppler transcraniano, que esteve alterado apenas numa criança; 72,1% realizaram ecocardiograma transtorácico, que revelou dilatação do ventrículo esquerdo em 21%; e 24,4% realizaram polissonografia, que revelou síndrome de apneia obstrutiva do sono em 95,2%. Cada criança teve em média quatro internamentos durante o período do estudo, sendo os diagnósticos mais frequentes crise vaso-oclusiva (38,3%), febre sem foco (23,4%), infeção respiratória alta (17,8%), pneumonia bacteriana e sequestro esplénico (10,7% cada) e agudização de anemia (9,5%). Discussão: Dada a cronicidade da DCF e a multiplicidade de comorbilidades associadas, é fundamental reforçar a importância do seguimento multidisciplinar e do envolvimento dos familiares no tratamento.

Abstract The aim of this study was to evaluate the time elapsed from first symptoms to the treatment of oral and oropharyngeal cancer (OOC) and to identify variables associated with treatment delay. This is an observational study with retrospective and prospective data collection. Patients with a diagnosis of OOC seen at the Head and Neck Surgery outpatient clinic of a Brazilian public hospital were included and followed up to treatment initiation. Participants answered a questionnaire for the collection of socioeconomic, demographic, cultural, and clinical information, as well as information about the time elapsed from first symptoms to the first appointment with a head and neck surgeon. Time to treatment was classified into four intervals: 1- first symptoms to first medical appointment; 2- first medical appointment to specialized medical care; 3- specialized medical care to preparation for treatment; and 4- preparation for treatment to treatment initiation. Bivariate statistics were computed. Out of 100 participants, nine died before treatment. Mean time to treatment was 217 days. Highest mean time was observed for interval 2 (94 days), followed by interval 1 (63 days), interval 4 (39 days), and interval 3 (21 days). At interval 1, a longer time was associated with severe alcohol consumption, severe smoking, and family history of cancer. At interval 2, the delay was associated with appointment with a general practitioner, clinical diagnosis of disease other than cancer, and antibiotic prescription. At interval 4, delay in treatment was associated with surgical treatment. Patients with OOC experience delays from symptom onset to treatment initiation. The longest interval was associated with professional delay, followed by patient delay in help-seeking.

ABSTRACT: This study aimed to know perception of the marital subsystem (parents) and to understand the dynamics of the family system in offer of pacifiers. Ten couples, parents of children between 4 and 7 years old, were interviewed by means of a semi-structured script of questions about the offer of pacifiers for their children. Answers by qualitative method of content analysis, using predefined categories of the General Systems Theory (homeostasis, circularity, globality, non- summativity, morphogenesis and equifinality). Pacifier offer reestablished the Homeotasis related to adaptation of mother in postpartum period; in introduction of artificial nipples due to allergy to breast milk and to avoid thumb sucking. Circularity occurred in paternal support to stimulate breastfeeding and in offer of pacifier to reduce the dependence of baby regarding the mother. Globality occurred when offer of pacifier softened mastitis and colic of baby. Non-somivity was evidenced in the mother's attitude in controlling behavior of children with offer of pacifier. Morphogenesis predominated in influence of extern al systems (health, school, kinship, marketing and social media) on family decision to offer pacifiers. Offer of pacifiers interfe red in Equifinality, favoring the organization of family system in face of complications in breastfeeding. Offer of pacifier sought to meet emergency needs of baby, although there was a perception of consequences for child's health in long term. General Theory of Systems allowed verifying the dynamics of family system, which can be applied by health professionals in order to understand the factors involved in offer of pacifiers.

RESUMEN: Este estudio tuvo como objetivo conocer la percepción del subsistema conyugal (padres) y comprender la dinámica del sistema familiar en la oferta de chupetes. Se entrevistó a diez parejas, padres de niños entre 4 y 7 años, mediante un guión semiestructurado de preguntas sobre la oferta de chupetes para sus hijos. Respuestas por método cualitativo de análisis de contenido, utilizando categorías predefinidas de la Teoría General de Sistemas (homeostasis, circularidad, globalidad, no sumatividad, morfogénesis y equifinalidad). La oferta de chupete restableció la Homeotasis relacionada con la adaptación de la madre en el puerperio; en la introducción de pezones artificiales por alergia a la leche materna y para evitar chuparse el dedo. Ocurrió circularidad en el apoyo paterno para estimular el amamantamiento y en la oferta del chupete para reducir la dependencia del bebé con respecto a la madre. La globalidad ocurrió cuando la oferta del chupete suavizó la mastitis y el cólico del bebé. La no somividad se evidenció en la actitud de la madre en el control de la conducta de los niños con oferta de chupete. Predominó la morfogénesis en la influencia de los sistemas externos (salud, escuela, parentesco, marketing y redes sociales) en la decisión familiar de ofrecer chupetes. La oferta de chupetes interfirió en la Equifinalidad, favoreciendo la organización del sistema familiar frente a las complicaciones en la lactancia. La oferta del chupete buscó atender las necesidades de emergencia del bebé, aunque hubo una percepción de consecuencias para la salud del niño a largo plazo. La Teoría General de Sistemas permitió verificar la dinámica del sistema familiar, que puede ser aplicada por los profesionales de la salud para comprender los factores involucrados en la oferta de chupetes.

Abstract This work presents the study carried out in a Sewage Pumping Station after severe degradation was observed. The attack by biogenic sulfuric acid in sanitary sewage systems is widely studied in the literature, however, data on real work situations are still quite limited. Analyzes of the concentration of H 𝟐 𝐒 in the air, carbonation depth, compressive strength, petrography, SEM/EDS, XRD and chemical determinations were carried out in concrete cores extracted above the effluent level. The products identified on the surface were Gypsum, Jarosite, Ferrous Hydroxide, Ferrous Chloride and possibly Hisingerite. The results demonstrate the presence of products on the surface, from the dissolution of cement paste as well as from the 16 mm steel bars located in the attacked region.

Resumen Este trabajo presenta el estudio realizado en una Estación de Bombeo de Aguas Residuales luego de que se observara una severa degradación. El ataque por ácido sulfúrico biogénico en los sistemas de alcantarillado sanitario es ampliamente estudiado en la literatura, sin embargo, los datos sobre situaciones reales de trabajo aún son bastante limitados. Se realizaron análisis de concentración de H 2 S en el aire, profundidad de carbonatación, prueba de resistencia a la compresión, petrografía, SEM/EDS, XRD y determinaciones químicas en núcleos de concreto extraídos por encima del nivel del efluente. Los productos identificados en la superficie fueron yeso, jarosita, hidróxido ferroso, cloruro ferroso y posiblemente hisingerita. Los resultados demuestran la presencia en la superficie de productos de la disolución de pasta de cemento y barras de acero de 16 mm ubicadas en la región atacada.

Resumo Este trabalho apresenta o estudo realizado em uma Estação Elevatória de Esgoto após ser constatado severa degradação. O ataque por ácido sulfúrico biogênico em sistemas de esgoto sanitário é amplamente estudado na literatura, entretanto, dados em situações reais de obra ainda são bastante limitados. Foram realizadas análises da concentração de H 2 S no ar, profundidade de carbontação, ensaio de resistência à compressão, petrografia, MEV/EDS, DRX e determinações químicas em testemunhos de concreto extraídos acima do nível do efluente. Os produtos identificados na superfície foram Gipsita, Jarosita, Hidróxido Ferroso, Cloreto Ferroso e possivelmente Hisingerita. Os resultados demonstram a presença na superfície tanto de produtos oriundos da dissolução da pasta cimentícia quanto das barras de aço de 16 mm localizadas na região atacada.

Free-living amoeba (FLA) group includes the potentially pathogenic genera Acanthamoeba, Naegleria, Balamuthia, Sappinia, and Vermamoeba, causative agents of human infections (encephalitis, keratitis, and disseminated diseases). In Brazil, the first report on pathogenic FLA was published in the 70s and showed meningoencephalitis caused by Naegleria spp. FLA studies are emerging, but no literature review is available to investigate this trend in Brazil critically. Thus, the present work aims to integrate and discuss these data. Scopus, PubMed, and Web of Science were searched, retrieving studies from 1974 to 2020. The screening process resulted in 178 papers, which were clustered into core and auxiliary classes and sorted into five categories: wet-bench studies, dry-bench studies, clinical reports, environmental identifications, and literature reviews. The papers dating from the last ten years account for 75% (134/178) of the total publications, indicating the FLA topic has gained Brazilian interest. Moreover, 81% (144/178) address Acanthamoeba-related matter, revealing this genus as the most prevalent in all categories. Brazil’s Southeast, South, and Midwest geographic regions accounted for 96% (171/178) of the publications studied in the present work. To the best of our knowledge, this review is the pioneer in summarising the FLA research history in Brazil.

Abstract Free-living amoebae of the genus Acanthamoeba are the causative agents of granulomatous encephalitis and keratitis, severe human infections. Bioactive compounds from plants are recognized as an alternative source for the development of new drugs. The Amaryllidaceae is a botanical family able to synthesize a very specific and consistent group of biologically active isoquinoline-like alkaloids. The alkaloidal fractions from the Brazilian species Hippeastrum canastrense, H. diniz-cruziae, H. puniceum, and Crinum x amabile, along with the alkaloid lycorine, were investigated against Acanthamoeba castellanii. The in vitro assays were performed with distinct concentrations of lycorine and alkaloidal fractions, while the cell viability was evaluated by the MTT method upon MDCK cells. Chlorhexidine 0.02% was used as the positive control. The effect of alkaloid fractions was concentration dependent, and 2000 μg mL-1 of H. canastrense and H. diniz-cruziae provided a 100% inhibition. At concentrations of 250, 500, and 1000 μg mL-1, the H. diniz-cruziae alkaloidal fraction showed the lowest cytotoxic effect (5%-7%) and remarkable anti-amoebic activity, demonstrating values of IC50 285.61 μg mL-1, low cytotoxicity (5%-7%), and selectivity index (7.0). Taken together, the results are indicative of the great potential that the alkaloids from H. diniz-cruziae have as new candidates for anti-amoebicidal compounds.

Resumen: Este artículo tiene como objetivo comprender y discutir las complejas relaciones transnacionales inherentes a los contratos farmacéuticos entre Estados y empresas farmacéuticas transnacionales, especialmente en temas relacionados con las disposiciones de arbitraje transnacional para la solución de controversias y la obligación de formar fondos no soberanos como garantía de cumplimiento de deudas. Intentaremos demostrar que estas cláusulas encuentran su legitimidad en el contexto del Derecho Transnacional, en el que el Estado actúa como un actor no soberano, y que estas disposiciones contractuales se rigen por la lógica del favor creditoris. Se utilizó el método crítico y el procedimiento de investigación bibliográfica.

Abstract: In this work we discuss the complexities of transnational relations that are inserted in pharmaceutical contracts between States and Transnational Pharmaceutical Companies, particularly in the field of clauses that establish transnational arbitration, and the constitution of non-sovereign funds as guarantee of performance. We intend to show that these clauses are legitimate in the context of Transnational Law, where States act as non-sovereign actors, and that they are guided by favor creditoris logic. The critical method and the bibliographic research procedure were used.

Resumo: Esse artigo objetiva compreender e discutir as complexas relações transnacionais inerentes aos contratos farmacêuticos entre Estados e empresas farmacêuticas transnacionais, em especial nos tópicos relacionados às previsões de arbitragem transnacional para a solução de controvérsias e a obrigação de formação de fundos não-soberanos como garantia de adimplemento das dívidas. Procurar-se-á demonstrar que essas cláusulas encontram sua legitimidade no contexto do Direito Transnacional, na qual o Estado atua como um ator não soberano, e que estas previsões contratuais se orientam pela lógica favor creditoris. Se empregou o método crítico e o procedimento da pesquisa bibliográfica.

Résumé: Dans ce travail, nous discutons des complexités des relations transnationales qui s’insèrent dans les contrats pharmaceutiques entre États et Entreprises Pharmaceutiques Transnationales, notamment dans le domaine des clauses qui établissent l’arbitrage transnational et la constitution de fonds non souverains comme garantie de performance. Nous entendons montrer que ces clauses sont légitimes dans le contexte du droit transnational, où les États agissent comme des acteurs non souverains, et qu’elles sont guidées par une logique favor creditoris.

Abstract Objective: To investigate association between parental locus of control (belief of individuals about what or who has control of the events of their lives) and bottle feeding habits among children from 3 to 5 years of age. Methodology: Parental locus of control validated in Brazil, and semi-structured questionnaire to obtain sociodemographic, health, and oral habit behaviors was applied to mothers of 992 preschool children. Outcome variable “use of feeding bottle” was studied according to the time of its use (≤36 months and >36 months). Simple logistic regression models were adjusted and raw odds ratios were estimated for variables of distal blocks, which contemplated parental locus of control, socioeconomic characteristics of family, and maternal habits. In the intermediate block, the variables for conditions of the child's birth and place of health care attendance during the prenatal period and early childhood were included. In the proximal block, the time of breastfeeding and pacifier use were reported. Variables were analyzed from the distal to the proximal block, and the individual analyses that presented p ≤ 0.20 remained in each model; included in the subsequent block were the variables with p ≤ 0.10, because this was a study of prevention. Results: Longer time of feeding bottle use was associated with the internal parental locus of control, mothers older than 31 years of age, white race, premature children, who used pacifiers and are treated in the private health system. Conclusions: Children who maintained the habit of feeding bottle use for a longer time were those whose mother presented an internal locus of control.

Resumo Objetivo Investigar validade e fidedignidade de uma escala de rastreio para dislexia do desenvolvimento (DD) no ensino fundamental preenchida por professores. Método Avaliação empírica - 12 professores responderam a Escala de Leitura e Escrita (ELE) sobre 95 alunos de 3º ano do ensino fundamental, em dois momentos; os escolares realizaram testes de leitura e escrita (variáveis externas) para investigar a correlação entre a escala e o desempenho dos mesmos. Realizaram-se (1) análise fatorial, (2) avaliação da consistência interna, (3) investigação da relação entre um item da escala e o construto medido por teoria da resposta ao item (TRI) (4) correlação da escala com variáveis externas (Validade Convergente-VC); e (5) investigação da estabilidade temporal da avaliação. Resultados (1) a escala avalia um único fator; (2) o coeficiente alpha apontou que os itens são bons indicadores do construto; (3) a análise por TRI mostra que todos os itens foram monotônicos, indicando que um único construto determina a variabilidade (4) a correlação de Spearman foi moderada (11/17 itens), apontando a existência de VC; (5) o valor da correlação do coeficiente de estabilidade temporal indica que o resultado da ELE não varia de maneira significativa no tempo; (6) nove crianças obtiveram pontuações que sugerem encaminhamento para uma avaliação diagnóstica devido ao grau de dificuldade apresentado. Conclusão O estudo mostra evidências empíricas de validade e fidedignidade da ELE para rastreio de risco de DD. A porcentagem de crianças com suspeita de DD (aproximadamente 9%) corrobora a literatura internacional sobre prevalência de dislexia.

Abstract Purpose To investigate the empirical validity and reliability of a screener for risk of developmental dyslexia (DD) by elementary school teachers. Methods The scale was tested with 12 teachers who answered questions about their students (95 students total, all in the third year of elementary school); the students, in turn, performed reading and writing tasks which were used to investigate the association between screening scores and performance. The following analyses were carried out: (1) factor analysis; (2) internal consistency; (3) relationship between each scale item and the construct of interest, as measured by item response theory (IRT); (4) correlation of each scale item with external variables (reading and writing tests); and (5) the temporal stability of teachers’ evaluations. Results The analyses showed: (1) one factor was extracted; (2) strong internal consistency – the items in the scale are good indicators for screening of this construct; (3) items were monotonic (IRT), i.e., item variability is associated with one construct; (4) moderate Spearman correlation (11/17 items); (5) temporal stability – the result of screening did not vary over time. Conclusion This study shows evidence of validity and reliability of the proposed scale in its intended use of screening for developmental dyslexia. The percentage of children at risk for developmental dyslexia, according to the scale, was approximately 9%, which is in agreement with the international literature on the prevalence of dyslexia.

Abstract The native flora of the Brazilian rupestrian grassland (campos rupestres) is threatened by the spread of invasive grasses. In this study, we evaluated the effect of habitat on the functional traits and CSR ecological strategies of three invasive alien grasses occurring both in the ironstone (IRG) and quartzitic (QRG) rupestrian grassland habitats. Although in both habitats the invasive species predominantly showed a stress-tolerant strategy, they exhibited distinct degrees of stress-tolerance and slightly differences in functional traits values in the IRG compared to the QRG. Habitat type distinctly influenced invasive grasses functional traits and ecological strategies, revealing a species-specific pattern.

ABSTRACT Study of the mechanical characteristics of agricultural products is crucial to the development of equipment that can achieve the maximum efficiency without compromising the final product quality. Seeds crack and break when exposed to stresses that exceed their resistance to rupture. In this study, we aim to assess the mechanical properties of saccharine sorghum (Sorghum bicolor L. Moench) seeds at different moisture contents. The seeds were harvested in the municipality of Santa Helena - GO, Brazil and indicated an initial moisture content of 0.307 (d.b.). For each moisture content obtained (0.307, 0.258, 0.212, 0.170, 0.130, and 0.093 d.b.), samples were homogenized and subsequently analyzed. Compressive tests were performed through uniaxial tests in a sample of 15 seeds for each moisture content. In these tests, the "TA Hdi Texture Analyzer" universal testing machine was used, with a 250-N compression load cell. Our results indicated that the compressive force required to deform saccharine sorghum seeds decreased with increasing moisture content, whereas values of proportional modulus of deformity increased with both reduced moisture content and deformation. In addition, the reduction in moisture content caused an increase in the force required to rupture the seeds.

RESUMEN El estudio de las características mecánicas de los productos agrícolas es importante para que los equipos puedan desarrollarse y lograr la máxima eficiencia sin comprometer la calidad final de los alimentos. Las grietas y roturas de las semillas se producen cuando están expuestas a tensiones que exceden la resistencia del material. El objetivo de este trabajo fue evaluar algunas pro piedades mecánicas de las semillas de sorgo de sacarina (Sorghum bicolor L. Moench) con diferentes contenidos de humedad. Las semillas se cosecharon en el municipio de Santa Helena - GO, Brasil, y presentaron un contenido de humedad inicial de 0.307 base seca (b.s.). Para cada contenido de humedad obtenido (0,307; 0,258; 0,212; 0,170; 0,130 y 0,093 b.s.), las muestras fueron homogeneizadas y luego analizadas. Las pruebas de compresión uniaxial se realizaron en una muestra de 15 semillas para cada contenido de humedad. Para esta determinación se utilizó la máquina de prueba universal Analizador de textura TA Hdi, con una celda de carga de compresión de 250 N. Nuestros resultados evidenciaron que la fuerza de compresión necesaria para deformar las semillas de sorgo disminuyó con el aumento del contenido de humedad, mientras que los valores del módulo de deformidad proporcional se incrementaron con la reducción tanto del contenido de humedad como de la deformación. Además, la reducción del contenido de humedad aumentó la fuerza requerida para romper las semillas.

Resumo O presente artigo configura um estudo exploratório e analítico sob a emergente temática da compatibilização entre desenvolvimento econômico e as políticas públicas ambientais para concretização da dignidade da pessoa humana - desafio que se apresenta para as instâncias executivas em âmbito interno e externo. Entretanto, necessário se faz resguardar o meio ambiente para que tenha se vida com dignidade. Compatibilizar o meio ambiente, economia e desenvolvimento é um desafio constante. Assim, não se implanta uma política ambiental que não tenha como finalidade o desenvolvimento sustentável que contempla os aspectos sociais, ambientais e econômicos, financeiros e ideológicos e amparados pela dignidade humana. A partir da perspectiva crítica de desenvolvimento em Chang; e da teoria do desenvolvimento como liberdade de Amartya Sen, explora-se o tema da implementação de políticas públicas de incentivo à proteção e conservação do meio ambiente. Concentram-se as análises mais precisamente em relação às estratégias governamentais para cumprir a agenda do desenvolvimento sustentável, entre elas, destacam-se o Pagamento por Serviços Ambientais e o Bolsa Floresta na política institucional brasileira de atendimento às normas internacionais relativas à preservação ambiental. Conclui-se que há um importante esforço das instâncias executivas em implementar as políticas públicas ambientais. A tendência de expansão observada principalmente em relação à preservação do recurso natural “água” e a implementação do projeto Bolsa Floresta pelas instâncias executivas estaduais do Estado do Amazonas nos permite vislumbrar um futuro melhor do que se estas políticas fossem ignoradas. Cabe à sociedade a conscientização ambiental e a cobrança de novas elaborações das políticas públicas promotoras das boas práticas ambientais para um desenvolvimento sustentável de forma ordenada preservando tripé da economia, meio ambiental e o social.

Abstract This article sets out an exploratory and analytical study under the emerging theme of the compatibility between economic development and environmental public policies to achieve the dignity of the human person - a challenge that is presented to the executive bodies in the internal and external spheres. However, it is necessary to protect the environment so that one lives life with dignity. Compatibilizing the environment, economy and development is a constant challenge. Thus, an environmental policy that does not aim at sustainable development, which includes social, environmental, economic, financial and ideological aspects and supported by human dignity, is not implemented. From the critical perspective of development in Chang; and the theory of development as freedom of Amartya Sen, explores the theme of the implementation of public policies to encourage the protection and conservation of the environment. The analyzes focused more precisely on the government's strategies to fulfill the sustainable development agenda, among them the Payment for Environmental Services and Bolsa Floresta in the Brazilian institutional policy of meeting the international norms related to environmental preservation. It is concluded that there is an important effort of the executive bodies in implementing public environmental policies. The expansion trend observed mainly in relation to the preservation of the natural resource “water” and the implementation of the Bolsa Floresta project by the state executive authorities of the state of Amazonas allows us to envisage a better future than if these policies were ignored. It is up to society to raise environmental awareness and collect new elaborations of public policies that promote good environmental practices for sustainable development in an orderly manner while preserving the economic, environmental and social dimensions.

RESUMO A obtenção da área foliar é fundamental em vários estudos agronômicos, sendo um dos importantes instrumentos que avaliam o crescimento de uma planta. O objetivo do trabalho foi estimar equações e selecionar a mais apropriada na determinação não destrutiva da área foliar em Lichieira (Litchi chinensis Sonn.). A partir das dimensões lineares de comprimento (C) e largura máxima (L) do limbo foliar, as equações foram estimadas para os modelos linear, quadrático, potência e exponencial. A equação de regressão linear simples utilizando o produto do comprimento pela máxima largura, dada por Y = 0,2885 + 0,662 (C.L), é a que melhor expressa a estimativa da área foliar de Lichieira.

ABSTRACT Obtaining leaf area is critical in several agronomic studies, being one of the important instruments to assess plant growth. The aim of this study was to estimate equations and select the most appropriate in determining leaf area in litchi (Litchi chinensis Sonn.). From the linear dimensions of length (L) and maximum width (W) of leaf limb, equations were estimated using linear, quadratic, potential and exponential models. The linear regression equation using the product of the length by maximum width, given by Y = 0.2885 + 0.662 (L.W) is the one that best expresses the leaf area estimation of litchi tree.

Resumo O objetivo deste trabalho foi avaliar a dinâmica dos fluxos de óxido nitroso (N2O) em solo sob pastagem, em sistema de integração lavoura-pecuária, e sob cerrado nativo usado como referência, bem como identificar os atributos físicos e químicos do solo que influenciam esses fluxos. O estudo foi realizado na Fazenda Capivara, da Embrapa Arroz e Feijão, de 5 de fevereiro a 30 de setembro de 2013. As amostragens de gás foram realizadas com uso de câmaras estáticas manuais. O solo sob pastagem apresentou os maiores fluxos de N2O, com média de 14,12 ng m-2 s-1. Essa área também apresentou maior espaço poroso preenchido por água (EPPA), que, associado à temperatura e ao teor de nitrato no solo, influenciou a produção de N2O. Na época chuvosa, os fluxos apresentaram correlação positiva com o EPPA do solo e, na época seca, com seu teor de amônio e nitrato. A emissão total de N2O na área da pastagem foi de 1.644,19 gha1. No cerrado nativo, não houve emissão de N2O do solo para a atmosfera.

Abstract The objective of this work was to evaluate the dynamics of nitrous oxide (N2O) fluxes in a soil under pasture, in an integrated crop-livestock system, and in native cerrado as a reference, besides identifying the physical and chemical soil properties that affect the fluxes. The study was conducted at Fazenda Capivara of Embrapa Arroz e Feijão, in the state of Goiás, Brazil, between February 5 and September 30, 2013. Gas sampling was performed using manual static chambers. The soil under pasture showed the highest N2O fluxes with average of 14.12 ng m-2 s-1. This area also showed greater water-filled pore space (WFPS), which, associated with soil temperature and nitrate content in the soil affected the production of N2O. In the rainy season, fluxes showed positive correlation with soil WFPS, and, in the dry season, they were correlated with soil contents of ammonium and nitrate. The total N2O emission in the pasture area was 1,644.19 g ha-1. In native cerrado, there was no soil-N2O emission to the atmosphere.

Considerando que la transesterificación del aceite residual como resultado de la cocción de alimentos con la presencia de etanol no permite obtener biodiesel con concentración de etil éster superior a 96,5%, esta investigación muestra cómo se optimizaron las condiciones de la reacción con la adición de ácido oxálico. Con la ayuda de un diseño factorial fueron estudiados los efectos de la relación molar de etanol y aceite, así como la concentración del catalizador hidróxido de sodio en la presencia de ácido oxálico como activador del carbonilo en la fase aceite. El aceite usado se deshidrató y se filtró. La reacción fue realizada mediante la agitación mecánica durante un período de dos horas a 70° C. Los datos fueron modelados mediante la aplicación de la metodología de superficie de respuesta, encontrando las condiciones óptimas de la reacción. El camino propuesto demostró ser factible para la producción de biodiesel a partir de etanol y aceite residual con contenido de éster dentro de la concentración especificada por EN 14103 (superior a 96,5%). La metodología de superficie de respuesta mostró las condiciones ideales con la relación molar etanol:aceite de 6:1 y contenido de hidróxido de sodio de 1% respecto a la masa del aceite.

The usual transesterification of waste frying oil with ethanol does not give final concentration of biodiesel above 96.5%. The aim of this paper is to optimize the reaction conditions using ethanedioic acid as an activator of the carbonyl glyceryl ester. With the aid of a factorial design, the effects of the molar ratio of ethanol and oil, as well as the concentration of the catalyst sodium hydroxide were evaluated. The oil used was dehydrated and filtered, and the reactants submitted to mechanical stirring for two hours at 70° C. The data have been modeled by applying the response surface methodology, for the optimal reaction conditions. As results, the presence of ethanedioic acid drives transesterification from waste frying oil giving biodiesel with ester content over 96.5%. The response surface methodology gave the optimum conditions for the production of ethyl esters at molar ratio ethanol:oil of 6:1 and sodium hydroxide content of 1% relative to the mass of oil.