ABSTRACT Inadequate management of pasture soils in the Amazon has resulted in a predominance of degraded pastures. Considering the natural characteristics of this region can favor more appropriate strategies for sustainability, the objective of this study was to evaluate the differences in the chemical and physical attributes of pasture and forest soils in the Southern Amazon and to identify the most sensitive attributes of their fertility. Additionally, this study suggests appropriate management practices for sustainable pastures. Soil samples from the 0 to 0.20 m layer were analyzed to determine pH, exchangeable bases (calcium, magnesium, and potassium), exchangeable aluminum, potential acidity, phosphorus, organic carbon, bulk density, and texture. Pasture soils had a higher pH, calcium content, and bulk density than forest soils. However, the pasture soils had lower phosphorus and organic matter content. The soil organic carbon stocks were also lower in pasture soils, with levels 0.8 to 12 Mg ha-1 lower than in forest soils. The fertility attributes most sensitive to soil management in these pastures were phosphorus, pH, organic carbon, and bulk density. The lack of nutrients and soil and water conservation practices have contributed to the degradation of these pastures. Therefore, the recommended management for these pastures should aim to improve the organic matter content, reduce compaction, and replenish and cycle nutrients.

RESUMO O manejo inadequado de solos de pastagens na Amazônia resulta em predomínio de pastagens degradadas. Considerando as características naturais dessa região pode favorecer estratégias mais adequadas para sua sustentabilidade, o objetivo desse estudo foi avaliar as diferenças de atributos químicos e físicos de solos de pastagens e florestas no sul da Amazônia e identificar os atributos mais sensíveis de sua fertilidade. Além disso, sugerir práticas de manejo mais adequadas para essas pastagens em direção à sustentabilidade. Amostras de solo da camada de 0 a 0,20 m foram analisadas para determinação de pH, bases trocáveis (cálcio, magnésio e potássio), alumínio trocável, acidez potencial, fósforo, carbono orgânico, densidade aparente e textura. Os solos de pastagem tiveram maior pH, cálcio e densidade aparente do que os solos de floresta. No entanto, os solos de pastagem apresentaram menores teores de fósforo e matéria orgânica. Os estoques de carbono orgânico do solo também foram menores nas pastagens, com teores de 0,8 a 12 Mg ha-1 inferiores aos solos da floresta. Os atributos de fertilidade mais sensíveis ao manejo do solo nessas pastagens foram fósforo, pH, carbono orgânico e densidade aparente. A carência de nutrientes e de práticas de conservação do solo e da água têm contribuído para o estado de degradação dessas pastagens. Portanto, o manejo recomendado para essas pastagens deve visar a melhoria da matéria orgânica, redução da compactação, além da reposição e ciclagem de nutrientes.

Capillary electromigration techniques can be understood as the ones used to separate neutral compounds, solvated ions and ionized species, considering the differentiated migration among them when an electrical field is applied within a capillary column filled with a background electrolyte. Several existing capillary electrophoresis setups provide the possibility of developing reliable quantitative assays of inorganic ions, organic acids, fatty acids, amino acids, carbohydrates, nucleic acids, proteins, hormones, vitamins, macromolecules, and more. Therefore, given the chemical complexity of bodily fluid matrices, capillary electrophoresis (CE) and its variations present themselves as an advantageous strategy for enhancing traditional clinical diagnostic methods and for the development of new ones. The recent advances in the study of the human metabolome associated with technological improvements towards medical applications make CE a very useful and versatile technique for clinical laboratory assays. Within this context, this review has the purpose of presenting some traditional methods used for exams of blood, urine, saliva, feces, and sweat, and how CE can be implemented as a real alternative to enable faster, automated, and cost-effective analysis with a comprehensive perspective that shall result in better diagnostic possibilities for patients, being a powerful tool for helping physicians on the precision medicine achievements. compounds species electrolyte acids carbohydrates proteins hormones vitamins macromolecules more Therefore matrices (CE context blood urine saliva feces sweat faster automated costeffective cost effective patients achievements

ABSTRACT The use of biostimulants in second-crop maize (Zea mays) can promote higher physiological activity in plants, resulting in higher grain yield. This study aimed to evaluate the effects of phytohormones and nicotinamide on growth and yield traits of second-crop maize. The statistical design used was a randomized block design arranged in a factorial scheme with two doses of phytohormones (0 and 500 mL ha-1) × five concentrations of nicotinamide (0, 200, 400, 600, and 800 mg L-1) with four replications. The use of biostimulants favored all variables evaluated for the maize crop. The isolated use of phytohormones and nicotinamide promoted grain yields of 6089.6 and 6242.5 kg ha-1, respectively, representing gains of 6.0 and 11.6%, respectively, compared with the control. The application of 800 mg L-1 nicotinamide resulted in the highest maize grain yield. The use of phytohormones and nicotinamide, isolated or associated, was favorable for the growth characteristics and grain yield of second-crop maize. A synergistic effect was noted between phytohormones and nicotinamide on the first ear insertion height and number of rows per ear.

RESUMO O uso de bioestimulantes no milho segunda safra (Zea mays) pode promover maior atividade fisiológica das plantas, resultando em maior produtividade de grãos. Assim, este trabalho teve como objetivo avaliar as características de crescimento e produtividade do milho segunda safra sob aplicação de fitormônios e nicotinamida. O delineamento estatístico utilizado foi em blocos casualizados dispostos em esquema fatorial com 2 doses de fitohormônios (0 e 500 mL ha-1) × 5 concentrações de nicotinamida (0, 200, 400, 600 e 800 mg L-1) com quatro repetições. O uso dos dois bioestimulantes favoreceu todas as variáveis avaliadas para a cultura do milho. O uso isolado de fitormônios e nicotinamida promoveu produtividades de grãos de 6.089,6 e 6.242,5 kg ha-1, representando respectivamente, ganhos de 6,0 e 11,6%, em relação à testemunha. A aplicação de 800 mg L-1 de nicotinamida proporcionou maior produtividade de grãos de milho. O uso de fitohormônios e nicotinamida, isolados ou associados, foram favoráveis às características de crescimento e produtividade do milho segunda safra. Houve efeito sinérgico de fitormônios e nicotinamida para altura de inserção da primeira espiga e o número de fileiras por espiga.

Diethylene glycol is an extremely toxic substance to humans. Recently, cases of beer contamination in Brazil have raised awareness of the need for developing simple screening methods to evaluate this type of compound. This research developed a liquid-liquid extraction with low-temperature partitioning technique to determine diethylene glycol in beer via gas chromatography. Employing a flame-ionization detector simplifies the method, lowers its cost and therefore, it can be used as screening step to assess the possibility of contamination. A gas chromatograph coupled to a mass spectrometer would be used only for a confirmatory analysis. The optimized method was validated for the main figures of merit, and it proved to be adequate, with good values of recovery rate (94-106%), limit of detection (3.0 mg L-1), and quantification (10.0 mg L-1). Accuracy, in terms of repeatability and intermediate accuracy, showed variation coefficients lower than or equal to 20%. This method was applied to 28 samples of beers marketed in Brazil, and diethylene glycol was found above the limit of detection in three of them (10.7%). These results were confirmed by a gas chromatograph coupled to a mass spectrometer, which showed the reliability of the screening method for determining diethylene glycol in beer samples.

RESUMO Estresses abióticos associados causam efeitos e respostas diferentes da exposição a uma única fonte de estresse. Objetivou-se avaliar o efeito do estresse combinado de temperatura supraótima e déficit hídrico no processo germinativo de lotes de sementes de trigo com diferentes níveis de vigor. Sementes de trigo IPR Catuara de quatro lotes foram submetidas a germinação nos potenciais hídricos 0,000, - 0,075, - 0,223 e - 0,444 MPa, associados às temperaturas 20, 24, 28 e 32 ºC, totalizando 16 combinações de estresse. O delineamento experimental foi inteiramente casualizado, com quatro repetições, em esquema fatorial: quatro lotes x 16 combinações de estresse, e comparação de médias por Scott-Knott 5%. Avaliaram-se a germinação das plântulas normais aos quatro e oito dias, o conteúdo de proteína total e a atividade da catalase e ascorbato peroxidase (APX) na parte aérea e radicular das plântulas. As análises de componentes principais e de agrupamento hierárquico foram aplicadas à matriz original formada pelas 16 combinações, para a média dos quatro lotes. Sementes de trigo de maior vigor são mais tolerantes a combinação dos estresses hídrico e térmico. Não há prejuízo ao processo germinativo de trigo nas combinações sob temperaturas supraótimas até 28 °C e redução dos potenciais hídricos até -0,223 MPa. Independente da temperatura, o potencial hídrico -0,444 MPa diminui a porcentagem e a velocidade da germinação. A atividade da APX aumenta em condições de estresses hídrico e térmico atuando como defesa ao estresse oxidativo na germinação de trigo.

ABSTRACT Combined abiotic stresses have different effects and responses than exposure to a single source of stress. The objective of this study was to evaluate the effect of the combined stress of supra-optimal temperatures and water deficit on the germination of wheat seeds with different levels of vigor. Wheat seeds from four different lots of the IPR Catuara cultivar were germinated at water potentials of 0.000, -0.075, -0.223, and -0.444 MPa, associated with temperatures of 20 °C, 24 °C, 28 °C, and 32 °C, totaling 16 stress combinations. The experimental design was completely randomized in a factorial scheme with four replications (four seed lots × 16 stress combinations), and means were compared using Scott-Knott 5%. We evaluated the germination of normal seedlings at 4 and 8 d, the activity of catalase and ascorbate peroxidase (APX), and the protein content of the aerial and root parts of wheat seedlings. Principal components analysis and hierarchical clustering were applied to the original matrix formed by the 16 combinations for the average of the four lots. Wheat seeds with higher vigor were more tolerant to combined water and thermal stress. Temperatures up to 28 °C and reduction of water potentials down to -0.223 MPa did not prejudice the germination process of wheat seeds. Regardless of temperature, a water potential of -0.444 MPa decreased the percentage and rate of germination. APX activity increased under water stress and supra-optimal temperatures, acting as a defense mechanism against oxidative stress.

RESUMO: Physalis peruviana L. (fisális) apresenta grande potencial econômico devido ao sabor diferenciado de seus frutos. A produtividade dos pomares brasileiros é baixa em função do número limitado de variedades ou cultivares disponíveis. O principal entrave na seleção de genótipos superiores é a falta de informação sobre a variabilidade genética dentro e entre as populações de fisális e, possivelmente, a base genética limitada das mesmas, que pode ser explicada pelos processos evolutivos, de domesticação e de seleção das populações naturais ou artificiais. A fisális cultivada atualmente no Brasil é tetraploide e tal poliploidia pode ter levado ao isolamento reprodutivo da espécie, o qual impede a ocorrência de hibridação intraespecífica. As populações cultivadas provêm de um pool genético comum e, além disso, sofreram um longo processo de domesticação e seleção realizadas empiricamente pelos agricultores. Porém, na Colômbia e em outros países andinos existem populações silvestres que exibem diversidade genética que, embora sejam fundamentais para a conservação da espécie, apresentam baixo potencial para o desenvolvimento de genótipos com características agronômicas superiores. A fim de criar e ampliar a variabilidade genética de fisális, os melhoristas tem empregado várias estratégias incluindo a indução de mutação, a duplicação cromossômica e a hibridação inter e intraespecífica. Além disso, a produção de linhagens duplo-haploides a partir da cultura de anterasin vitro vem demonstrando bons resultados para a seleção de híbridos. Os genótipos mutantes e/ou híbridos obtidos através dos métodos citados em associação com os de seleção genômica ampla podem gerar cultivares com características agronômicas superiores.

ABSTRACT: Physalisperuviana L. (physalis) has significant economic potential by virtue of the unique flavor of its fruit. However, the productivity of Brazilian plantations is low because of the limited number of varieties or cultivars available. The main obstacle in the selection of superior genotypes is the lack of information about genetic variability within- and between- populations and limited genetic basis that has likely resulted from evolutionary, domestication and selection processes of the natural or artificial populations. Physalis currently cultivated in Brazil is tetraploid, and such polyploidy may have led to the reproductive isolation of the species, preventing the occurrence of intraspecific hybridization. Moreover, cultivated populations derive from a common gene pool and have undergone a long process of domestication and selection carried out empirically by farmers. In Colombia and other Andean countries there are wild populations that exhibit genetic diversity which; although, fundamental for the conservation of the species, have low potential for the development of genotypes with superior agronomic traits. In order to create and expand the genetic variability of physalis, breeders have employed various strategies including induction of mutation, chromosome duplication, and interspecific and intraspecific hybridization. Furthermore, the production of double haploid lines from in vitro anther cultures has shown good results in the selection of hybrids. The mutant genotypes and/or hybrids obtained using these methods in association with those of wide genomic selection can generate cultivars with superior agronomic traits.

RESUMO: Objetivou-se com este trabalho estudar o controle genético de caracteres relacionados à qualidade do fruto do melão. Foram avaliadas as gerações F1, F2, RC1, RC2 dos cruzamentos OL x A-16 e OL x PV em dois ensaios separados conduzidos em blocos casualizados com três repetições. Os caracteres avaliados foram: peso médio do fruto, índice de formato, espessura da polpa, firmeza da polpa, sólidos solúveis e porcentagem de rachadura. As análises foram feitas por meio de estudo clássico de gerações envolvendo modelos mistos. Foram estimados os parâmetros de herdabilidades nos sentidos amplo e restrito e número de loci que controlam o caráter. A herança dos caracteres estudados é complexa com a presença de gene de efeito maior e poligenes com efeitos aditivos e de dominância.

ABSTRACT: This research studied the genetic control of the traits related to melon fruit quality. The F1, F2, BC1, BC2 generations from the OL x A-16 and OL x PV crossings were evaluated in two separate trials conducted in randomized blocks with three replications. The evaluated traits were: average fruit weight, shape index, pulp thickness, pulp firmness, soluble solids content and cracking rate. The analyses were accomplished through a classic study of generations involving mixed models. The parameters on heritability and number of loci controlling the traits were evaluated in a broad and narrow sense. The inheritance of the evaluated traits is complex, presenting one gene of greater effect and polygenes with additive and dominant effects.

ABSTRACT OBJECTIVE To evaluate the quality of information on gestational syphilis (GS) and congenital syphilis (CS) on the Sistema de Informação de Agravos de Notificação (SINAN-Syphilis Brazil – Notifiable Diseases Information System) by compiling and validating completeness indicators between 2007 and 2018. METHODS Overall, care, and socioeconomic completeness scores were compiled based on selected variables, by using ad hoc weights assigned by experts. The completeness scores were analysed, considering the region and area of residence, the pregnant woman’s race/colour, and the year of case notification. Pearson’s correlation coefficients were used to validate the scores obtained by the weighted average method, compared with the values obtained by principal component analysis (PCA). RESULTS Most selected variables presented a good or excellent degree of completeness for GS and CS, except for clinical classification, pregnant woman’s level of education, partner’s treatment, and child’s race/colour, which were classified as poor or very poor. The overall (89.93% versus 89.69%) and socioeconomic (88.71% versus 88.24%) completeness scores for GS and CS, respectively, were classified as regular, whereas the care score (GS-90.88%, and CS-90.72%) was good, despite improvements over time. Differences in the overall, care and socioeconomic completeness scores according to region, area of residence, and ethnic-racial groups were reported for syphilis notifications. The completeness scores estimated by the weighted average method and PCA showed a strong linear correlation (> 0.90). CONCLUSION The completeness of GS and CS notifications has been improving in recent years, highlighting the variables that form the care score, compared with the socioeconomic scores, despite differences between regions, area of residence, and ethnic-racial groups. The weighted average was a viable methodological alternative easily operationalised to estimate data completeness scores, allowing routine monitoring of the completeness of gestational and congenital syphilis records.

RESUMO Este trabalho descreve os resultados do programa Extension for Community Healthcare Outcomes para eliminação do câncer do colo do útero nas Américas (ECHO ELA), desenvolvido na forma de cooperação trilateral entre a Organização Pan-Americana da Saúde (OPAS), o Instituto Nacional do Câncer dos Estados Unidos (NCI) e o MD Anderson Cancer Center da Universidade do Texas (MD Anderson). O programa visa a disseminar estratégias para a prevenção do câncer do colo do útero e está estruturado em torno dos três pilares da estratégia de eliminação do câncer do colo do útero da Organização Mundial da Saúde (OMS) e das Metas 90-70-90 associadas. O público-alvo inclui autoridades sanitárias de países da América Latina e do Caribe, bem como os pontos focais de doenças não transmissíveis nas representações da OPAS nos países, além de colaboradores clínicos e de saúde pública. Todos os meses, são realizadas sessões virtuais de uma hora e meia em espanhol usando o formato ECHO®. No período de maio de 2020 a junho de 2021, foram realizadas 14 sessões do ECHO, com uma média de 74 participantes por sessão (variação: 46 a 142). Foram realizadas duas enquetes anônimas (linha de base e acompanhamento) e dois grupos focais. Os entrevistados afirmaram que os tópicos sobre os quais mais aprenderam foram a situação da vacinação contra o HPV na região e as estratégias para implementar a vacinação contra o HPV. As necessidades identificadas incluíam apoio entre as sessões do ECHO e assistência técnica específica para o país. O programa ECHO ELA oferece um fórum para aumentar a colaboração entre os países da América Latina e do Caribe e difundir melhores práticas para atingir as metas de eliminação do câncer do colo do útero da OMS.

RESUMEN Se describen los resultados del programa ECHO® (Extension for Community Healthcare Outcomes) para la eliminación del cáncer cervicouterino en las Américas (ECHO-ELA), que se concibió como una cooperación trilateral entre la Organización Panamericana de la Salud (OPS), el Instituto Nacional del Cáncer de los Estados Unidos (NCI) y el centro contra el cáncer MD Anderson (MD Anderson) de la Universidad de Texas. La finalidad del programa es difundir las estrategias para la prevención del cáncer cervicouterino, y está estructurado en torno a los tres pilares de la estrategia para la eliminación del cáncer cervicouterino de la Organización Mundial de la Salud (OMS) y los objetivos 90-70-90 conexos. El público destinatario comprende autoridades de salud de países de América Latina y el Caribe, así como los puntos focales de la OPS para las enfermedades no transmisibles en las Representaciones en los países, además de colaboradores en el ámbito clínico y de la salud pública. Las sesiones virtuales se llevan a cabo en español, durante 1,5 horas cada mes, utilizando el formato ECHO®. De mayo del 2020 a junio del 2021 se celebraron 14 sesiones de ECHO, con un promedio de 74 participantes por sesión (límites: 46-142). Se realizaron dos encuestas anónimas (al inicio y de seguimiento) y dos grupos de opinión. Los encuestados declararon que los temas sobre los que más aprendieron fueron la situación de la vacunación contra el VPH en la región y las estrategias para poner en marcha la vacunación contra el VPH. Entre las necesidades mencionadas figuraban el apoyo entre las sesiones de ECHO y la asistencia técnica específica para cada país. El programa ECHO-ELA brinda un foro para una mayor colaboración entre los países de América Latina y el Caribe y para difundir las estrategias sobre las mejores prácticas, a fin de alcanzar los objetivos de la OMS de eliminación del cáncer cervicouterino.

ABSTRACT We describe the outcomes of The Extension for Community Healthcare Outcomes-Elimination of Cervical Cancer in The Americas (ECHO-ELA) program, which was developed as a tri-lateral cooperation between Pan American Health Organization (PAHO), the U.S. National Cancer Institute (NCI) and The University of Texas MD Anderson Cancer Center (MD Anderson). The program’s purpose is to disseminate strategies for cervical cancer prevention and is structured around the three pillars of the World Health Organization’s (WHO) Cervical Cancer Elimination Strategy and the associated 90-70-90 target goals. The target audience includes health authorities from Latin American and Caribbean countries, as well as PAHO’s non-communicable disease Focal Points in country offices as well as clinical and public health collaborators. The virtual sessions are held in Spanish for 1.5 hours every month using the ECHO® format. From May 2020 to June 2021, 14 ECHO sessions were held with an average of 74 participants per session (range: 46 – 142). We conducted two anonymous surveys (baseline and follow up) and two focus groups. Respondents stated that the topics they learned the most about included the state of HPV vaccination in the region and strategies for implementing HPV vaccination. Identified needs included support between ECHO sessions and country-specific technical assistance. The ECHO-ELA program provides a forum for increased collaboration between countries in Latin America/Caribbean and the dissemination of best-practice strategies to reach the WHO Cervical Cancer Elimination target goals.

Abstract Preterm birth (PTB) is the main condition related to perinatal morbimortality worldwide. The aim of this study was to identify gene-environment interactions associated with spontaneous PTB or its predictors. We carried out a retrospective case-control study including parental sociodemographic and obstetric data as well as newborn genetic variants of 69 preterm and 61 at term newborns born at a maternity hospital from Tucumán, Argentina, between 2005 and 2010. A data-driven Bayesian network including the main PTB predictors was created where we identified gene-environment interactions. We used logistic regressions to calculate the odds ratios and confidence intervals of the interactions. From the main PTB predictors (nine exposures and six genetic variants) we identified an interaction between low neighbourhood socioeconomic status and rs2074351 (PON1, genotype GG) variant that was associated with an increased risk of toxoplasmosis (odds ratio 12.51, confidence interval 95%: 1.71 - 91.36). The results of this exploratory study suggest that structural social disparities could influence the PTB risk by increasing the frequency of exposures that potentiate the risk associated with individual characteristics such as genetic traits. Future studies with larger sample sizes are necessary to confirm these findings.

Abstract Spinal muscular atrophy (SMA) is considered one of the most common autosomal recessive disorders, with an estimated incidence of 1 in 10,000 live births. Testing for SMA has been recommended for inclusion in neonatal screening (NBS) panels since there are several therapies available and there is evidence of greater efficacy when introduced in the pre/early symptomatic phases. In Brazil, the National Neonatal Screening Program tests for six diseases, with a new law issued in 2021 stating that it should incorporate more diseases, including SMA. In the present study, dried blood spot (DBS) samples collected by the Reference Services of Neonatal Screening of RS and SP, to perform the conventional test were also screened for SMA, using real-time PCR, with SALSA MC002 technique. A total of 40,000 samples were analyzed, enabling the identification of four positive cases of SMA, that were confirmed by MLPA. Considering our sampling, Brazil seems to have an incidence comparable to the described in other regions. This work demonstrated that the use of the MC002 technique in samples routinely collected for the conventional NBS program is suitable to screen for SMA in our conditions and can be included in the expansion of the neonatal screening programs.

BACKGROUND Dendritic cells (DCs) specific intercellular adhesion molecule (ICAM)-3-grabbing non integrin receptor (DC-SIGN) binds to subgenera Leishmania promastigotes mediating its interaction with DC and neutrophils, potentially influencing the infection outcome. OBJECTIVES In this work, we investigated whether DC-SIGN receptor is expressed in cells from cutaneous leishmaniasis (CL) lesions as well as the in vitro binding pattern of Leishmania (Viannia) braziliensis (Lb) and L. (L.) amazonensis (La) promastigotes. METHODS DC-SIGN receptor was labeled by immunohistochemistry in cryopreserved CL tissue fragments. In vitro binding assay with CFSE-labeled Lb or La promastigotes and RAJI-transfecting cells expressing DC-SIGN (DC-SIGNPOS) or mock-transfected (DC-SIGNNEG) were monitored by flow cytometry at 2 h, 24 h and 48 h in co-culture. RESULTS In CL lesion infiltrate, DC-SIGNPOS cells were present in the dermis and near the epidermis. Both Lb and La bind to DC-SIGNPOS cells, while binding to DC-SIGNNEG was low. La showed precocious and higher affinity to DC-SIGNhi population than to DC-SIGNlow, while Lb binding was similar in these populations. CONCLUSION Our results demonstrate that DC-SIGN receptor is present in L. braziliensis CL lesions and interact with Lb promastigotes. Moreover, the differences in the binding pattern to Lb and La suggest DC-SIGN can influence in a difference way the intake of the parasites at the first hours after Leishmania infection. These results raise the hypothesis that DC-SIGN receptor could participate in the immunopathogenesis of American tegumentary leishmaniasis accounting for the differences in the outcome of the Leishmania spp. infection.

ABSTRACT Macaw palm (Acrocomia aculeata) is a potential raw material for biodiesel production owing to its high oil content. In this study, a model is created that can estimate the oil percentage in Macaw fruit using spectral indices obtained via computer vision. Ninety Macaw fruits are used to perform an experiment. They are categorized into three stages of maturation and counted in terms of weeks after flowering. Images of the fruits are captured using a multispectral camera in the visible spectral region (RGB) and infra-red regions (NIR), which allows spectral indices to be obtained. A model is established using the principal component regression method and used to estimate the oil content based on the colorimetric characteristics of Macaw palm fruits. The selected model is composed of the first two principal components, which indicate an explanatory potency of 91.57% of the variance. Applying this information to the validation data, the model exhibits a determination coefficient of 0.91, mean square error of 10.61%, and standard error of 5.46% in terms of the oil content, which indicates that computer vision is a promising alternative method for estimating oil content.

ABSTRACT Nitrogen (N) fertilizer management is a key factor in the success of maize crops. The objective of this work was to evaluate the response of second-crop maize to N applied exclusively as topdressing or at planting + topdressing. Five experiments were conducted in areas in southwestern Goiás in 2019 and 2020 to evaluate N application rates of 0 and 30 kg ha-1 at planting, combined with five N rates applied as topdressing at the maize V3 stage over a total of 0, 75, 150, 225, and 300 kg ha-1. Dry matter production in the V6 or V9 stage and yield parameters at harvest were evaluated. N application did not affect the number of grain rows per ear but increased the number of grains per row and, particularly, grain weight. The crop responded positively to increases in the total N rate in 4 of the 5 experiments: in 1 of these experiments, N fertilizer application at planting contributed to an increase in the efficiency of topdressing fertilization, resulting in a higher maize yield with a lower total N rate; in the other 3, a positive maize response to N occurred when total N was applied as topdressing at V3. However, the highest mean maize grain yield (8,233 kg ha-1) was found in the trial that showed no response to N fertilizer application - probably due to the better chemical fertility conditions of the area combined with an adequate distribution of rainfall, considering the multiple factors involved in N application recommendations.

RESUMO O manejo de nitrogênio (N) na cultura do milho é fator chave para o sucesso de seu cultivo, de modo que se objetivou com esse estudo avaliar a resposta da cultura, em segunda safra, à doses de N aplicadas exclusivamente em cobertura ou na adubação de base (semeadura) complementada com a adubação de cobertura. Para tal, em 2019 e 2020 foram realizados cinco experimentos em áreas da região Sudoeste do Estado de Goiás, testando 0 e 30 kg ha-1 de N aplicados na base combinados com cinco doses totais de N (0, 75, 150, 225 e 300 kg ha-1) completadas em cobertura, quando as plantas estavam em estádio V3. Avaliou-se a produção de massa seca na fase vegetativa V6 ou V9, e, por ocasião da colheita, os parâmetros produtivos. Verificou que a aplicação de N não interfere no número de fileiras de grãos, mas aumenta o número de grãos por fileira e, principalmente, o peso de grãos. Em 4 dos 5 ensaios, a cultura respondeu positivamente ao incremento da dose total de N; em 1 desses, a adubação de base contribuiu para aumento da eficiência da adubação de cobertura, de modo que a produtividade do milho foi maior e atingida com uma dose total de N menor. Nos outros 3, respostas positivas foram observadas quando da aplicação total do N em cobertura e em dose única. A maior produtividade média de grãos de milho (8.233 kg ha-1), no entanto, ocorreu justamente no ensaio com ausência de resposta à adubação nitrogenada - provavelmente devido às melhores condições de fertilidade química da área aliada à adequada distribuição das chuvas, considerando assim múltiplos fatores para N recomendações de aplicação.

Abstract Based on the genetic, morphological, and morphometric data of blood gamonts, we identified Hepatozoon parasites in colubrid snakes sampled in the Eastern Amazon region. Hepatozoon trigeminum was detected in the mussurana snake Clelia clelia and exhibited wide and elongated gamonts (mean dimensions: 14.25±0.65 × 4.31±0.43 μm) with an evident parasitophorous vacuole. Hepatozoon odwyerae sp. nov. was described in the indigo snake Drymarchon corais, whose gamonts have elongated and thin bodies (mean dimensions: 13.41±0.79 × 3.72±0.35 μm) with one end more tapered than the other. Phylogenetic analyses, based on the amplification of a 441 bp fragment of the 18S rRNA gene, revealed that the novel sequences of Hepatozoon spp. from our study were closely related to hemogregarine lineages found in lizards and snakes from Brazil, forming a well-supported monophyletic clade with them. The present study provides the first species description of Hepatoozon in D. corais and a new record of a host species for C. clelia using the integrated taxonomic data. We also highlight the importance of further investigations into the diversity of Hepatozoon in snakes, a rich but underestimated group of parasites, especially in the Amazonian biome.