Study of Temporal Variations in Species–Environment Association through an Innovative Multivariate Method: MixSTATICO

[EN]The study of biotic and abiotic factors and their interrelationships is essential in the preservation of sustainable marine ecosystems and for understanding the impact that climate change can have on different species. For instance, phytoplankton are extremely vulnerable to environmental changes and thus studying the factors involved is important for the species’ conservation. This work examines the relationship between phytoplankton and environmental parameters of the eastern equatorial Pacific, known as one of the most biologically rich regions in the world. For this purpose, a new multivariate method called MixSTATICO has been developed, allowing mixed-type data structured in two different groups (environment and species) to be related and measured on a space–time scale. The results obtained show how seasons have an impact on species–environment relations, with the most significant association occurring in November and the weakest during the month of May (change of season). The species Lauderia borealis, Chaetoceros didymus and Gyrodinium sp. were not observed in the coastal profiles during the dry season at most stations, while during the rainy season, the species Dactyliosolen antarcticus, Proboscia alata and Skeletonema costatum were not detected. Using MixSTATICO, species vulnerable to specific geographical locations and environmental variations were identified, making it possible to establish biological indicators for this region

TORRE DE TV DIGITAL DE BRASÍLIA: ANÁLISE ESTRUTURAL DOS CARREGAMENTOS EÓLICOS POR ELEMENTOS FINITOS

Em conformidade com a complexidade estrutural de diversas obras arquitetônicas de Oscar Niemeyer, a Torre de TV Digital de Brasília se destaca no que tange aos seus aspectos social, arquitetônico, estrutural, geográfico e aerodinâmico. Estando localizada em uma região de elevada altitude, livre de barreiras físicas em sua vizinhança, é constituída basicamente de uma geometria em forma de casca em concreto armado, tendo “braços” acoplados lateralmente, servindo como suporte estrutural para as cúpulas geodésicas. Sua extensão vertical compreende um tamanho de 120 metros. Tal estrutura está sujeita a consideráveis carregamentos eólicos. Este trabalho apresenta um modelo computacional em três dimensões que inclui o acoplamento fluido-estrutural para a Torre de TV Digital de Brasília, utilizando o método de elementos finitos. Neste contexto, as equações de campo Estrutural e Navier-Stokes dependentes do tempo são resolvidas numericamente. Diferentes perfis de escoamentos e deslocamentos da estrutura são analisados, considerando a influência da pressão e da intensidade da velocidade de escoamento eólico sobre a Torre. Neste estudo, são obtidos os perfis de velocidade do vento considerando diferentes disposições geométricas da Torre em relação ao escoamento eólico. Considera-se a velocidade de entrada sobre a Torre com perfil parabólico, sendo que o valor máximo é de 45,264 m/s, de acordo com os parâmetros intrínsecos estipulados para a velocidade característica descrita pela norma NBR 6123 (1988). O escoamento eólico sobre o modelo dá-se através ângulos de entrada 0º, 45º e 90º. Os máximos carregamentos e deslocamentos são obtidos e comparados com os valores pré-definidos para construções existentes na referida norma. A influência do carregamento eólico sobre a estrutura é realizada mediante a análise sistemática de curvas altura versus pressão

Modelos alométricos para estimar altura de árvores em florestas ecotonais do norte da Amazônia

Allometric models defining the relationship between stem diameter and total tree height in the Amazon basin are important because they refine the estimates of tree carbon stocks and flow in the region. This study tests different allometric models to estimate the total tree height from the stem diameter in an ecotone zone between ombrophilous and seasonal forests in the Brazilian state of Roraima, in northern Amazonia. Stem diameter and total height were measured directly in 65 recently fallen trees (live or dead). Linear and nonlinear regressions were tested to represent the D:H relation in this specific ecotone zone. Criteria for model selection were the standard error of the estimate (Syx) and the adjusted coefficient of determination (R²adj), complemented by the Akaike Information Criterion (AIC). Analysis of residuals of the most parsimonious nonlinear models showed a tendency to overestimate the total tree height for trees in the 20-40 cm diameter range. Application of our best fitted model (Michaelis-Menten) indicated that previously published general equations for the tropics that use diameter as the independent variable can either overestimate tree height in the study area by 10-29% (Weibull models) or underestimate it by 8% (climate-based models). We concluded that our site-specific model can be used in the ecotone forests studied in Roraima because it realistically reflects the local biometric relationships between stem diameter and total tree height. Studies need to be expanded in peripheral areas of northern Amazonia in order to reduce uncertainties in biomass and carbon estimates that use the tree height as a variable in general models.Modelos alométricos que definem o relacionamento entre diâmetro do tronco e a altura total da árvore na bacia amazônica são importantes porque refinam as estimativas de fluxo e estoques de carbono arbóreo na região. Este estudo testou diferentes modelos alométricos para estimar a altura total de árvores a partir do diâmetro do tronco em uma zona de ecótono entre florestas ombrófilas e sazonais no estado de Roraima, norte da Amazônia. Diâmetro do tronco e altura total foram medidos de forma direta em 65 árvores tombadas recentemente (vivas e mortas). Regressões linear e não-linear foram testadas para representar a relação D:H nesta zona específica de ecótono. Os critérios de seleção dos modelos foram o erro padrão da estimativa (Syx), o coeficiente de determinação ajustado (R²adj) e o Critério de Informação de Akaike (AIC). A análise dos resíduos dos modelos não-lineares mais parcimoniosos mostrou uma tendência de superestimar a altura total para árvores entre 20-40 cm de diâmetro do tronco. A aplicação do modelo melhor ajustado (Michaelis-Menten) indicou que equações gerais publicadas previamente para os trópicos que usam diâmetro como variável independente podem superestimar em 10-29% (modelos Weibull) ou subestimar em 8% (modelos baseados no clima) a altura das árvores na área de estudo. Nós concluímos que o modelo de melhor ajuste pode ser usado nas florestas ecotonais estudadas em Roraima, porque ele reflete realisticamente o relacionamento biométrico local entre diâmetro do tronco e altura total da árvore. É necessário expandir os estudos para outras áreas periféricas do norte da Amazônia, com o intuito de reduzir as incertezas em estimativas de biomassa e carbono arbóreo que adotem altura da árvore como uma variável em modelos gerais

Efecto de la progesterona plasmática en la competencia para el desarrollo embrionario in vitro de vacas Bos taurus taurus y Bos taurus indicus

Studies have shown that progesterone has a direct effect on oocyte quality and early embryonic development. The objective of this study was to evaluate the effect of plasma progesterone (P4) concentration on in vitro embryo development in Bos taurus taurus (Holstein) and Bos taurus indicus (Gyr) cows. Multiparous Holstein and Gyr cows were used, and they were presynchronized with the application of two doses of D-cloprostenol with an interval of 11 days. They were latter distributed in one of three experimental groups induced to different plasma levels of progesterone: control group was synchronized using only D-cloprostenol without exogenous progesterone, low progesterone group received an auricular implant of norgestomet of second use, and high progesterone group received two new auricular implants of norgestomet. The plasma progesterone concentration was significantly different (P < 0.05) for both Holstein cows (0.22 ± 0.15, 2.23 ± 0.17 and 5.32 ± 0.22 ng/mL) and Gyr cows (0.24 ± 0.19, 2.05 ± 0.17, 4.85 ± 0.20 ng/mL) between control, low progesterone, and high progesterone groups respectively. Gyr cows presented differences (P < 0.05) in the cleavage rate of the low progesterone group in relation to the control and high progesterone groups (87.9 % ± 0.11 vs. 77.5 % ± 0.13 and 76.4 % ± 0.10, respectively) and in the variable blastocyst rate of the low progesterone group (48.3 % ± 0.16) in relation to the control group (35.8 % ± 0.10) and the high progesterone group (30.4 % ± 0.20). It is concluded that there is an effect of progesterone on embryonic development of Gyr cows. However, this effect is not evidenced in Holstein cows.Diversos estudios han comprobado que la progesterona tiene un efecto directo en la calidad ovocitaria y el desarrollo inicial embrionario. El objetivo de este estudio fue evaluar el efecto de la concentración de la progesterona (P4) plasmática en el desarrollo de embriones in vitro en vacas de raza Bos taurus taurus (Holstein) y Bos taurus indicus (Gyr). Se utilizaron vacas Holstein y Gyr multíparas, presincronizadas con la aplicación de dos dosis de D-cloprostenol con intervalo de once días. Posteriormente, se distribuyeron en uno de tres grupos experimentales inducidos a diferentes niveles plasmáticos de progesterona. El grupo control fue sincronizado utilizando únicamente D-cloprostenol sin progesterona exógena, el grupo progesterona baja recibió un implante auricular de norgestomet de segundo uso y al grupo progesterona alta se le aplicaron dos implantes auriculares de norgestomet nuevos. Los resultados evidencian que la concentración plasmática de progesterona fue significativamente diferente (P < 0,05) tanto para las vacas Holstein (0,22 ± 0,15, 2,23 ± 0,17 y 5,32 ± 0,22 ng/mL) como para las vacas Gyr (0,24 ± 0,19, 2,05 ± 0,17, 4,85 ± 0,20 ng/mL) entre los grupos control, progesterona baja y progesterona alta, respectivamente. Las vacas Gyr presentaron diferencia (P < 0,05) en la tasa de clivaje del grupo progesterona baja en relación con los grupos control y progesterona alta (87,9 % ± 0,11 vs 77,5 % ± 0,13 y 76,4 % ± 0,10, respectivamente) y en la variable tasa de blastocistos del grupo progesterona baja (48,3 % ± 0,16) en relación con el grupo control (35,8 % ± 0,10) y el grupo progesterona alta (30,4 % ± 0,20). Se concluye que la progesterona tuvo efecto sobre el desarrollo embrionario en vagas de raza Gyr, el cual no se evidenció en las vacas de raza Holstein

Chemical and nano-mineralogical study for determining potential uses of legal Colombian gold mine sludge: Experimental evidence

The present study is focused on the chemical and nano-mineralogical characterization of sludge from gold mine activities, in order to put forward diverse solution alternatives, where lack of knowledge has been found. The sample was collected from “La Estrella” mine of Suarez, located in Department of Cauca, south-west Colombia. The sludge micro-structure and chemical composition were analyzed using a high resolution transmission electron microscopy (HR-TEM) equipped with a dispersive X-ray detector (EDS). X-ray diffraction technique was employed to identify the mineralogical phases present in the sludge. Additional mineralogical characterization was done by using RAMAN spectroscopy. Main findings points to its potential to be used as a fertilizer, this is why, mine sludge contains macronutrients such as P, Ca and S, together with micronutrients like Cu. However, the presence of goethite could decrease the mobilization of nutrients to soils, thus additional alternatives, for instance, a mixture with humus or another material containing Humic Acids should be done, in order to minimizing its retention effect. Additionally, another possible uses to explore could be as construction and ceramic material or in the wastewater treatment for nutrient retention and organic material removal. Rutile (TiO2 nanoparticles) particles have been also detected, what could cause health concern due to its nanoparticle toxic character, mainly during gold extraction process

Worldwide topology of the scientific subject profile: a macro approach in the country level

[Background] Models for the production of knowledge and systems of innovation and science are key elements for characterizing a country in view of its scientific thematic profile. With regard to scientific output and publication in journals of international visibility, the countries of the world may be classified into three main groups according to their thematic bias.[Methodology/Principal Findings] This paper aims to classify the countries of the world in several broad groups, described in terms of behavioural models that attempt to sum up the characteristics of their systems of knowledge and innovation. We perceive three clusters in our analysis: 1) the biomedical cluster, 2) the basic science & engineering cluster, and 3) the agricultural cluster. The countries are conceptually associated with the clusters via Principal Component Analysis (PCA), and a Multidimensional Scaling (MDS) map with all the countries is presented.[Conclusions/Significance] As we have seen, insofar as scientific output and publication in journals of international visibility is concerned, the countries of the world may be classified into three main groups according to their thematic profile. These groups can be described in terms of behavioral models that attempt to sum up the characteristics of their systems of knowledge and innovation

Tocilizumab in visual involvement of giant cell arteritis: a multicenter study of 471 patients

Background: Visual involvement is the most feared complication of giant cell arteritis (GCA). Information on the efficacy of tocilizumab (TCZ) for this complication is scarce and controversial. Objective: We assessed a wide series of GCA treated with TCZ, to evaluate its role in the prevention of new visual complications and its efficacy when this manifestation was already present before the initiation of TCZ. Design: This is an observational multicenter study of patients with GCA treated with TCZ. Methods: Patients were divided into two subgroups according to the presence or absence of visual involvement before TCZ onset. Visual manifestations were classified into the following categories: transient visual loss (TVL), permanent visual loss (PVL), diplopia, and blurred vision. Results: Four hundred seventy-one GCA patients (mean age, 74 +/- 9 years) were treated with TCZ. Visual manifestations were observed in 122 cases (26%), of which 81 were present at TCZ onset: PVL (n = 60; unilateral/bilateral: 48/12), TVL (n = 17; unilateral/bilateral: 11/6), diplopia (n = 2), and blurred vision (n = 2). None of the patients without previous visual involvement or with TVL had new episodes after initiation of TCZ, while only 11 out of 60 (18%) patients with PVL experienced some improvement. The two patients with diplopia and one of the two patients with blurred vision improved. Conclusion: TCZ may have a protective effect against the development of visual complications or new episodes of TVL in GCA. However, once PVL was established, only a few patients improved

Robust Off- and Online Separation of Intracellularly Recorded Up and Down Cortical States

BACKGROUND: The neuronal cortical network generates slow (<1 Hz) spontaneous rhythmic activity that emerges from the recurrent connectivity. This activity occurs during slow wave sleep or anesthesia and also in cortical slices, consisting of alternating up (active, depolarized) and down (silent, hyperpolarized) states. The search for the underlying mechanisms and the possibility of analyzing network dynamics in vitro has been subject of numerous studies. This exposes the need for a detailed quantitative analysis of the membrane fluctuating behavior and computerized tools to automatically characterize the occurrence of up and down states. METHODOLOGY/PRINCIPAL FINDINGS: Intracellular recordings from different areas of the cerebral cortex were obtained from both in vitro and in vivo preparations during slow oscillations. A method that separates up and down states recorded intracellularly is defined and analyzed here. The method exploits the crossover of moving averages, such that transitions between up and down membrane regimes can be anticipated based on recent and past voltage dynamics. We demonstrate experimentally the utility and performance of this method both offline and online, the online use allowing to trigger stimulation or other events in the desired period of the rhythm. This technique is compared with a histogram-based approach that separates the states by establishing one or two discriminating membrane potential levels. The robustness of the method presented here is tested on data that departs from highly regular alternating up and down states. CONCLUSIONS/SIGNIFICANCE: We define a simple method to detect cortical states that can be applied in real time for offline processing of large amounts of recorded data on conventional computers. Also, the online detection of up and down states will facilitate the study of cortical dynamics. An open-source MATLAB toolbox, and Spike 2-compatible version are made freely available

Ecoepidemiology of Alphaviruses and Flaviviruses

Within the ecosystems, the balance is important since the populations maintain their size and the food habits that are constant over time; in contrast, the disappearance of natural sources or the alteration of habitat at different levels can cause major changes in the very structure of the ecosystem. Alterations in the habitats produced by human activity result in global warming, climatic changes, which together with globalization, increased trade, the shortening of distances thanks to transport, the increase in population and the socioeconomic activities of human cause imbalances. In many cases the vectors and hosts have adapted to the changes and have risen to higher latitudes and altitudes, which could contribute to the appearance of outbreaks or new outbreaks of new arboviruses of public health importance. Different cohabiting species can be reservoirs or vectors of arboviruses such as alphaviruses and flaviviruses. Currently, some viruses transmitted by mosquito vectors, such as dengue virus, Zika virus, and chikungunya virus, have caused epidemic outbreaks with important effects on human populations. It is possible that the expansion of vectors and their diseases reaches developed countries such as the United States and the European Union with a great impact on public health. The clinical signs of the diseases produced by arboviruses can vary from nonspecific febrile syndrome, encephalitis, hemorrhagic fever, and even death. Vectors and reservoirs in some cases are insects, such as mosquitoes and ticks; wild birds are reservoirs for the West Nile virus, small wild mammals such as rodents, bats, and domestic animals involved in food production can potentially harbor arboviruses, and the ecoepidemiological role of these is unknown. © 2020 Elsevier Inc. All rights reserved

Tapping into non-English-language science for the conservation of global biodiversity.

The widely held assumption that any important scientific information would be available in English underlies the underuse of non-English-language science across disciplines. However, non-English-language science is expected to bring unique and valuable scientific information, especially in disciplines where the evidence is patchy, and for emergent issues where synthesising available evidence is an urgent challenge. Yet such contribution of non-English-language science to scientific communities and the application of science is rarely quantified. Here, we show that non-English-language studies provide crucial evidence for informing global biodiversity conservation. By screening 419,679 peer-reviewed papers in 16 languages, we identified 1,234 non-English-language studies providing evidence on the effectiveness of biodiversity conservation interventions, compared to 4,412 English-language studies identified with the same criteria. Relevant non-English-language studies are being published at an increasing rate in 6 out of the 12 languages where there were a sufficient number of relevant studies. Incorporating non-English-language studies can expand the geographical coverage (i.e., the number of 2° × 2° grid cells with relevant studies) of English-language evidence by 12% to 25%, especially in biodiverse regions, and taxonomic coverage (i.e., the number of species covered by the relevant studies) by 5% to 32%, although they do tend to be based on less robust study designs. Our results show that synthesising non-English-language studies is key to overcoming the widespread lack of local, context-dependent evidence and facilitating evidence-based conservation globally. We urge wider disciplines to rigorously reassess the untapped potential of non-English-language science in informing decisions to address other global challenges. Please see the Supporting information files for Alternative Language Abstracts