Tamanho de coleção original, métodos de agrupamento e amostragem para obtenção de coleção nuclear de germoplasma

O objetivo deste trabalho foi verificar o efeito do tamanho da coleção original de germoplasma sobre eficácia de diferentes métodos de agrupamento e de amostragem, utilizados na obtenção de coleções nucleares, e comparar esses métodos no estabelecimento de coleções nucleares. Foram simulados sete tamanhos de coleções originais e utilizadas sete estratégias de amostragem para estabelecimento de coleções nucleares, com uso de caracteres morfo-agronômicos. Oito estratégias de obtenção de coleção nuclear foram empregadas, seis com técnicas de agrupamento (Tocher e Tocher sequencial) e duas sem agrupamento (aleatória e Tocher invertido). Nas estratégias de agrupamento, foram empregadas as amostragens constante, logarítmica e proporcional. Determinaram-se a variância explicada, o valor do coeficiente de determinação, o coeficiente de coincidência e o coeficiente de coincidência do desvio-padrão entre a coleção nuclear e a coleção original. As estratégias de amostragem constante e logarítmica geram coleções nucleares representativas da coleção original. O agrupamento de Tocher sequencial é mais eficaz na representação da coleção original pela coleção nuclear do que o agrupamento de Tocher. Entre as estratégias avaliadas, a amostragem pelo método de Tocher com critério de aglomeração inverso foi a mais eficiente na geração de coleções nucleares representativas das coleções originai

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

The biogeography of the Amazonian tree flora

We describe the geographical variation in tree species composition across Amazonian forests and show how environmental conditions are associated with species turnover. Our analyses are based on 2023 forest inventory plots (1 ha) that provide abundance data for a total of 5188 tree species. Withinplot species composition reflected both local environmental conditions (especially soil nutrients and hydrology) and geographical regions. A broader-scale view of species turnover was obtained by interpolating the relative tree species abundances over Amazonia into 47,441 0.1-degree grid cells. Two main dimensions of spatial change in tree species composition were identified. The first was a gradient between western Amazonia at the Andean forelands (with young geology and relatively nutrient-rich soils) and central–eastern Amazonia associated with the Guiana and Brazilian Shields (with more ancient geology and poor soils). The second gradient was between the wet forests of the northwest and the drier forests in southern Amazonia. Isolines linking cells of similar composition crossed major Amazonian rivers, suggesting that tree species distributions are not limited by rivers. Even though some areas of relatively sharp species turnover were identified, mostly the tree species composition changed gradually over large extents, which does not support delimiting clear discrete biogeographic regions within Amazonia

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Implementation of a geographic information system (GIS) for the planning of beekeeping in the west region of Paraná

This study aimed to develop a Geographic Information System (GIS), for storage of information and geographic location of apiaries in eight counties in western Paraná; study the local flora; the land used; and the honey productivity in the harvest of 2010 in two of these areas: Marechal Cândido Rondon and Santa Helena. In order to do so we used the software SPRING, delimiting a radius of action of bees of three kilometers around the apiaries. We interviewed and registered 126 beekeepers with 383 apiaries. By using the images we selected areas with greater and lower overlap of hives in Marechal Cândido Rondon (144 and 44 hives, respectively) and Santa Helena (165 and 40 hives, respectively), in a three kilometers radius, selecting 15 colonies in each area, for the study of the parameters cited. In the multivariate analysis of the grouping, five groups were formed, by their similarity of management, indicating the higher average production in the hives of the most populated area of Santa Helena and lower average production in the most populated of Marechal Cândido Rondon. The grouping of hives, the differences in the production of honey and floristic survey indicated that these differences could be associated with management, floristic and climatic differences recorded in the period of production, in the areas studied

Estratégias de amostragem e estabelecimento de coleções nucleares Strategies for sampling and establishment of core collections

O objetivo deste trabalho foi avaliar a influência da intensidade de amostragem, do tamanho da coleção de germoplasma inicial e da variância da amostragem sobre a qualidade das respectivas coleções nucleares, quanto à representatividade das coleções iniciais. Foram simulados sete tamanhos de coleções iniciais e utilizadas seis intensidades de amostragem para estabelecimento de coleções nucleares, utilizando caracteres morfoagronômicos. Determinaram-se o número de grupos formados, o coeficiente de coincidência entre a coleção nuclear e a coleção inicial e o coeficiente de determinação dos acessos amostrados para comporem a coleção nuclear. Também foi proposto o uso de uma estratégia alternativa para estabelecer coleções nucleares, de forma a maximizar a diversidade entre os acessos. O tamanho da coleção inicial influencia a intensidade de amostragem empregada na obtenção da coleção nuclear. A amostragem de acessos pelo método de Tocher, com critério de aglomeração inverso, mostrou-se eficiente na obtenção de coleções nucleares. As diferentes magnitudes de variância das coleções iniciais não influenciaram os coeficientes de determinação (R²) nem os coeficientes de coincidência entre a coleção inicial e as respectivas coleções nucleares.<br>The objective of this work was to evaluate the effect of sampling intensity, initial collection's size and its variance over the quality of the respective core collections, in terms of representation of the initial collections. Therefore, simulations were performed for seven sizes of the initial collections and six sampling intensities for the establishment of core collections were used, comprising morpho-agronomic traits. Groups formed were determined, as well as the coincidence coefficient between the core and the initial collection, and the determination coefficient of the accessions sampling to compose the core collection. The use of an alternative strategy was proposed to establish core collections, this strategy maximizes the diversity among the accessions. The size of initial collections affects the sampling intensity to be used to obtain a core collection. The selection of accessions with the method of Tocher, comprising criteria of inverse grouping, was efficient for the formation of the core collections. The different magnitudes of variance of the initial collections did not affect either the coefficient of determination (R²) or the coincidence rate between initial collections and respective core collection

Considerações clínicas e etiológicas das síndromes epilépticas sintomáticas com paroxismos occipitais bloqueados à abertura dos olhos Clinical and ethiological considerations about the symptomatic epileptic syndromes with occipital paroxism bloqued when the eyes open

A síndrome da epilepsia parcial com paroxismos occipitais no eletrencefalograma (EEG) mostra características clínicas heterogêneas. Visando descrever esta rara forma de epilepsia, investigamos a significância dos achados eletrofisiológicos e clínicos em oito pacientes com paroxismos occipitais bloqueados pela abertura dos olhos. Os pacientes foram submetidos a exames radiológicos de RNM do encéfalo e/ou TC de crânio. Houve concordância entre as alterações do EEG e do tipo de crise em 5 pacientes, e entre as anormalidades anatômicas na TC ou RNM com anormalidades focais no EEG em 7 casos. Nossos resultados confirmam que este padrão inusitado origina-se de uma expressão eletrográfica multifatorial.<br>The syndrome of idiophatic partial epilepsy with occipital paroxysms in the EEG shows a considerable clinical heterogeneity. The present paper investigated the signficance of electrophysiologic and clinical characteristics in eigth patients with occipital paroxysms blocked by the eye opening. All patients were submitted to radiological exams including brain MRI and/or CT. There was agreement between EEG findings and type of seizures in 5 patients and between anatomical abnormalities in the MRI or CT and EEG focal abnormalities in 7 patients. Our results confirm that the unusual pattern comes from eletrographic multifactors origins

Predição de ganhos genéticos em progênies de polinização aberta de Eucalyptus urograndis cultivadas em diferentes ambientes e submetidas a diferentes procedimentos de seleção Prediction of genetic gains in open pollinated Eucalyptus urograndis cultivated in different environments and submitted to different selection procedures

O objetivo deste estudo foi comparar as estimativas de ganhos genéticos obtidas por diferentes métodos de seleção de genótipos em híbridos de Eucalyptus grandis x Eucalyptus urophylla (E. urograndis). Estimativas de progresso genético foram obtidas considerando-se a prática da seleção massal, seleção massal estratificada, seleção entre e dentro de progênies e seleção combinada, com avaliações em três locais distintos, visando ao desenvolvimento de genótipos com adaptação específica a cada um desses três ambientes. A análise de variância propiciou a constatação da existência de diferenças significativas, a 1% de probabilidade, pelo teste F, entre os diversos genótipos avaliados nas diferentes localidades. Essa diferença foi verificada nas três variáveis analisadas (diâmetro à altura do peito, altura média das plantas e volume total de madeira), o que permitiu inferir sobre a existência de variabilidade genética entre progênies. A população híbrida estudada possuía bom potencial produtivo e suficiente variabilidade genética a ser explorada por seleção. Os métodos de seleção apresentaram estimativas semelhantes de ganhos genéticos.<br>The objective of this study was to compare the genetic gain estimates obtained by different selection strategies for identification of Eucalyptus grandis x Eucalyptus urophylla genotypes with specific environmental adaptation. The genetic progress obtained by mass selection, stratified mass selection, selection among and within families and combined selection was evaluated in three contrasting environments. Variance analysis showed a significant difference at 1% of probability according to the F test among the different genotypes evaluated in these three environments. This genetic divergence was observed in all the evaluated traits: diameter at breast height, plant height and wood volume, allowing inferring the existence of genetic variability among families. The hybrid population studied presents good yield potential and genetic variability to be explored by selection. The selection methods showed similar estimates of genetic progress, supporting the decision to use the most practical strategies