Sampling and sample size in the estimation of maize ear traits

O trabalho teve como objetivo avaliar os efeitos das amostragens aleatória e não-aleatória e de tamanhos da amostra sobre as estimativas do número de grãos/espiga (NGE), comprimento (CS) e peso (PS) do sabugo, de dez cultivares de milho, e sobre a análise de variância dos dados. Na amostragem aleatória (A) as espigas foram selecionadas com o auxílio de uma tabela de dígitos aleatórios. Na amostragem não-aleatória (NA), o amostrador procurou ser "aleatório" sem usar, no entanto, nenhum mecanismo de sorteio. Como tamanhos amostrais foram usados 1, 3, 5, 7, 9, 11, 13 e 15 espigas, de um total de 26 espigas produzidas na área útil de cada parcela. Utilizou-se o delineamento de blocos ao acaso com cinco repetições. Os resultados da aplicação do teste F para comparar cultivares são concordantes com os métodos A e NA, quanto a NGE. Nos outros dois caracteres ocorreram discordâncias entre os dois métodos de amostragem, com alguns tamanhos amostrais. Somente houve diferenças entre tamanhos amostrais em relação a PS. Entre métodos de amostragem ocorreram diferenças quanto a NGE e PS. Para estimar os referidos caracteres, é necessário o uso de pelo menos 11 espigas por parcela, a fim de se obterem estimativas com boa precisão experimental, economia de tempo, e recursos financeiros.The objective of this study was to evaluate the effects of random and non-random sampling and sample size on estimates and variance analysis for number of grains/ear (NGE), cob length (CL) and cob weight (CW) of ten cultivars. In the random sampling the plants were selected with the aid of a random number table. In the non-random sampling, the sampler tried to be random, but no random mechanism was used. The sample sizes studied were 1, 3, 5, 7, 9, 11, 13 and 15 ears for 26 ears harvested in each plot. The experiment was arranged in a randomized block design with five replications. F-test results for both sampling methods were in agreement for NGE, but not for CL and CW. There were differences between sampling methods for NGE and CW. It was concluded that at least 11 ears must be selected for estimation of the mentioned traits. This number of plants can be easily handled and requires much less labor input than sample sizes

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Controle de plantas daninhas por meio da consorciação com Gliricídia. II. Cultura do milho

Um dos principais interesses da agricultura moderna é a redução no uso de herbicidas; para isso, diversas alternativas estão sendo investigadas, inclusive a consorciação. A cobertura do solo com ramos de gliricídia (Gliricidia sepium) não tem efeito alelopático sobre o milho ou feijão, mas diminui significativamente a população de algumas espécies de plantas daninhas. O objetivo deste estudo foi avaliar os rendimentos de espigas verdes e de grãos de cultivares de milho, em resposta ao controle de plantas daninhas, por meio da consorciação com gliricídia. Utilizou-se o delineamento de blocos ao acaso com parcelas subdivididas e cinco repetições. Os cultivares 1051, AG 2060, BRS 2020 e PL 6880 (atribuídos às parcelas) foram submetidos aos seguintes tratamentos: sem capina, duas capinas (realizadas aos 20 e 40 dias após a semeadura) e consorciação com gliricídia. Esta planta foi cultivada em um sistema de transplantio, para garantir germinação uniforme e rápido estabelecimento no campo. A semeadura foi feita em bandejas de 200 células, com uma semente por célula (volume de 35 mL). As plantas emergiram dois a três dias após a semeadura e foram transplantadas para o local definitivo dois a três dias após a emergência. O milho foi semeado no mesmo dia em que a gliricídia foi transplantada. Dezesseis espécies de plantas daninhas ocorreram em diferentes frequências, com distribuição desuniforme na área experimental. Os cultivares AG 1051 e AG 2060 foram os melhores quanto à maioria das características avaliadoras do rendimento de milho verde. O cultivar AG 1051 foi o melhor quanto ao rendimento de grãos. Os maiores rendimentos de espigas verdes e de grãos foram obtidos com duas capinas. Todavia, o fato de as parcelas consorciadas terem apresentado médias intermediárias às médias das parcelas não-capinadas e capinadas – em algumas características avaliadoras do rendimento de espigas verdes e no rendimento de grãos – indica que a gliricídia foi benéfica ao milho e exerceu certo controle sobre as plantas daninhas. _________________________________________________________________________________ ABSTRACTA reduction in herbicide use is one of modern agriculture’s main interests and several alternatives are being investigated with this objective, including intercropping. Gliricídia (Gliricidia sepium) mulch has no allelopathic effect on corn or beans but significantly decreased the population of some weed species. The objective of this study was to evaluate green ear and grain yield in corn cultivars as a response to weed control achieved via intercropping with gliricidia. A completely randomized block design with five replicates and split-plots was used. Cultivars AG 1051, AG 2060, BRS 2020, and PL 6880 (assigned to plots) were submitted to the following treatments: no hoeing, hoeing (performed at 20 and 40 days after sowing the corn), and corn intercropped with gliricidia. Gliricidia was grown in a transplanting system to ensure uniform germination and fast establishment in the field. Seeding was made in 200-cell trays with one seed per cell (35 mL volume). The plants emerged two to three days after sowing and were transplanted to a permanent site two to three days after emergence. Corn was sown on the same day gliricidia was transplanted. Sixteen weed species occurred at different frequencies, with uneven distribution in the experimental area. Cultivars AG 1051 and AG 2060 were the best with reference to most characteristics employed to evaluate green corn yield. Cultivar AG 1051 provided the highest grain yield. The highest green ear yield and grain yield values were obtained with hoeing. However, the fact that intercropped plots showed intermediate yield between the values obtained for hoed and non-hoed plots indicates that gliricidia was beneficial to corn, and exerted a certain level of weed control

Simple bone cyst : description of 60 cases seen at a Brazilian School of Dentistry and review of international literature

The aim of this study was to describe the relative frequency and the main demographic and clinic-radiographic features related to patients diagnosed with Simple bone cyst (SBC) in an Oral Diagnosis Service in Southeast Brazil and present a review and discussion of international literature on this topic. SBC cases from our service encompassing the period between 1978 and 2017 were selected. In addition, a literature search was performed in the Pubmed/MEDLINE online electronic database published between 1951 and 2019. A total of 2,459 cystic lesions were documented in our service, thus 60 patients were diagnosed with the SBC representing 2.4% of all jaw cystic. Most of cases were asymptomatic. Multiple SBC lesions were seen in two patients (3.4%) and association with cemento-osseous dysplasia was seen in one female patient (1.7%). A total of 793 cases were enrolled in this literature review. The SBC is an asymptomatic lesion often discovered in routine image exams in young patients. The unilocular, well defined margin with scalloped appearance is characteristic and helps the definition of diagnosis. This review suggests a different epidemiologic trend concerning to the sex and it confirms the posterior region of mandible as the more frequent location. The conservative treatment with limited exploration and curettage remains as the gold-standard treatment

Use of graphene as an additive to improve the mechanical properties of gypsum plaster

This work aimed to investigate the effects of graphene nanoparticles on the mechanical and morphological properties of gypsum plaster paste. In order to do so, samples of pure gypsum plaster paste with multilayer graphene were produced. These samples were prepared with a water/plaster factor (w/p) of approximately 0.5 with different graphene dosages. The mechanical analysis results showed that the graphene dosage of 0.02% increased the compressive and tensile strength values in the order of 120%. The increase in these properties is most likely due to the heat dissipation promoted by graphene, the greater production of crystalline nuclei and the reactivity of graphene with Ca2+ ions. Regarding the plaster setting times, a reduction in the values was observed for most samples, indicating an increase in the production of crystalline nuclei. FTIR analyzes indicate that there were no changes in terms of chemical properties

VARIATION ON MAIZE GREEN EARS AND GRAIN YIELD IN RESPONSE TO WEED COMPETITION

The objective of this study was to verify whether maize cultivars behave differently, in competition with weeds, to produce green ears and grain. Randomized complete block design was used, with split-plots and five replications. Cultivars AG 405, AG 2060, BA 8517, BA 9513, DKB 435 and EX 6005, applied to the plots, underwent the following treatments: without weeding and two weedings (22 and 41 days after planting). Only ten weed species were found in the experiment, many of which were gramineae. There was no difference among cultivars in relation to the number of weeds m-2. The number of weeds in the weeded plots (70.0 m-2) was superior to the one of the no-weeded plots (32.8 m-2). The cultivars only differed in grain yield when the weeds were controlled, with BA 8517 cultivar standing out as being superior. Therefore, the cultivars presented different reductions in grain yield with the presence of weeds suggesting that some (AG 405, BA 9513 and EX 6005) are more competitive than others against weeds. The weeds reduced green ears yield, in addition to 16 of the 26 evaluated characteristics, including some traits of the stalk, leaves, tassel, ear and grain

APLICAÇÃO DE EXTENSÃO DE NAVEGADOR DE INTERNET NA PLATAFORMA CURRÍCULO LATTES PARA OBTENÇÃO DE DADOS E ANÁLISE DE PONTUAÇÃO DE ARTIGOS PUBLICADOS EM PERIÓDICOS

Construímos este estudo com a finalidade de apresentar e analisar a aplicação de extensão de navegador de internet sobre a plataforma Currículo Lattes para demonstrar informações detalhadas da pontuação de artigos publicados em periódicos.  A disponibilidade de mais informações sobre a pontuação de publicações qualificadas dos pesquisadores na Plataforma do Currículo Lattes do CNPq pode auxiliar as instituições de ensino superior a construírem planos de trabalho dos seus servidores que levam em consideração a produção acadêmica? Procedemos metodologicamente utilizando a pesquisa bibliográfica, documental e a demonstração da utilização das extensões QLattes e Qualis no Lattes, considerando o período histórico de 2018 a 2023. As conclusões evidenciaram ser possível, a partir de disponibilização de dados quantificados, uma instituição acompanhar a produção de seu quadro docente e, ao mesmo tempo, ter condições de construir planos de trabalho considerando as atividades acadêmicas de seus profissionais