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Intestinal infections caused by non-typhoidal Salmonella spp., along with antimicrobial resistance spread are a major food safety concern worldwide. Here, we evaluate the potential of competitive exclusion products developed by anaerobic or aerobic conditions to control systemic infection, cecal colonization, fecal excretion, and improve the intestinal health in broilers challenged by Salmonella Heidelberg (SH). A total of 105 day-old chickens were randomly distributed into three experimental groups: A (untreated control), B (treated with anaerobic culture), and C (treated with aerobic culture). During 21 days, morphometric parameters of the small intestine were analyzed using microscopy, fecal excretions by cloacal swabs, systemic infection, and cecal colonization by colony-forming unit counts (CFU/g). The results indicated the lowest number of positive swabs (45.33%) recovered from Group C, followed by Group B (71.8%) and Group A (85.33%). The bacterial enumeration revealed the lowest amounts in Group C at the necropsy realized in 5-, 7-, and 14-days post-infection (DPI) (P = 0.0010, P = 0.0048, and P = 0.0094, respectively). Statistical differences between intestinal morphometrics were observed in the Group C at 21 DPI. Our results suggest that the product developed under aerobic conditions can improve intestinal health, protecting birds against SH.

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Object-oriented programming (OOP) embodies a software development paradigm grounded in representing real-world entities as objects, facilitating a more efficient and structured modelling approach. In this article, we explore the synergy between OOP principles and the TypeScript (TS) programming language to create a JSON-formatted database designed for storing arrays of biological features. This fusion of technologies fosters a controlled and modular code script, streamlining the integration, manipulation, expansion, and analysis of biological data, all while enhancing syntax for improved human readability, such as through the use of dot notation. We advocate for biologists to embrace Git technology, akin to the practices of programmers and coders, for initiating versioned and collaborative projects. Leveraging the widely accessible and acclaimed IDE, Visual Studio Code, provides an additional advantage. Not only does it support running a Node.js environment, which is essential for running TS, but it also efficiently manages GitHub versioning. We provide a use case involving taxonomic data structure, focusing on angiosperm legume plants. This method is characterized by its simplicity, as the tools employed are both fully accessible and free of charge, and it is widely adopted by communities of professional programmers. Moreover, we are dedicated to facilitating practical implementation and comprehension through a comprehensive tutorial, a readily available pre-built database at GitHub, and a new package at npm.

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Abstract The Global South has witnessed increasing sampling of its immense biological diversity during the past century. However, the diversity of many regions remains unknown, even at pristine and highly threatened places, such as in the Atlantic Forest; and for bioindicator, umbrella, and flagship groups. The present study reports the first butterfly list of the Parque Estadual Intervales, São Paulo, Brazil and surroundings, a key protected area in the last massive continuous of the Atlantic Forest. We compiled data from museums and four years of field work, under three sampling methods. We also aimed at providing resources to support conservation efforts by analyzing 27 years of climatic data (detailed in the Supplementary Material, in English and in Portuguese), discussing our results also for non-academics, and producing scientific outreach and educational material. A companion article dealt with the experiences of science outreach and capacity development, and illustrated the butterfly catalogue of the species sampled in the park. We found 312 species that sum to 2,139 records. The museum had 229 species (432 records), and we sampled 142 species (1,682 individuals), in a total effort of 36,679 sampling hours (36,432 trap and 247 net and observation hours). The richest families were Nymphalidae (148 species) and Hesperiidae (100 species). Most species were sampled exclusively by active methods (79.8%), but other sources (passive sampling, citizen science, etc.) also found unique records. We found the highest diversity metrics from January to May, and we demonstrated that winter months had less richness and abundance. We illustrated the 20 species common to all regions, and listed those that were found more than seven months in the year, as well as the most abundant species in trap sampling, with forest dwellers as well as species common to open and fragmented areas. The dominant species in our trap datasets was the iridescent white morpho, Morpho epistrophus (Fabricius, 1796), and we suggest it to become the park butterfly mascot.

Resumo O Sul Global testemunhou crescente amostragem de sua imensa diversidade biológica durante o século passado. Entretanto, a diversidade de muitas regiões permanece desconhecida, mesmo em locais pristinos e altamente ameaçados, como na Mata Atlântica; e para grupos bioindicadores, guarda-chuva e emblemáticos. O presente estudo reporta a primeira lista de borboletas do Parque Estadual Intervales, São Paulo, Brasil e arredores, uma unidade de conservação chave no último maciço contínuo de Mata Atlântica. Compilamos dados de museus e quatro anos de campo, sob três métodos de amostragem. Também visamos oferecer recursos para apoiar os esforços de conservação, analisando 27 anos de dados climáticos (detalhados no Material Suplementar, em inglês e em português), discutindo nossos resultados numa linguagem também para não acadêmicos, e produzindo material de divulgação científica e educativos. Um artigo irmão tratou das experiências de divulgação científica e capacitação, e ilustrou o catálogo de borboletas das espécies amostradas no parque. Encontramos 312 espécies em 2.139 registros. O museu tinha 229 espécies (432 registros), e amostramos 142 espécies (1.682 indivíduos), em um esforço total de 36.679 horas de amostragem (36.432 armadilhas e 247 horas de rede e observação). As famílias mais ricas foram Nymphalidae (148 espécies) e Hesperiidae (100 espécies). A maioria das espécies foi amostrada exclusivamente por métodos ativos (79,8%), mas outras fontes (passiva, ciência cidadã, etc.) também encontraram registros únicos. Encontramos as maiores métricas de diversidade de janeiro a maio, e demonstramos que os meses de inverno tiveram menos riqueza e abundância. Ilustramos as 20 espécies comuns a todas as regiões, e listamos aquelas que foram encontradas em mais de sete meses no ano, bem como as espécies mais abundantes em armadilhas, com espécies florestais e também comuns em áreas abertas e fragmentadas. A espécie dominante em nossas armadilhas foi a morfo branca iridescente, Morpho epistrophus (Fabricius, 1796), e sugerimos que se torne a borboleta mascote do parque.

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Objective: The population's adhesion to measures to ensure social distancing represents a great management challenge in a pandemic context. Despite of evidence shown that social distancing is effective, lack of adherence still persists in many countries. Therefore, it is challenging to separate the effectiveness of government measures, from social distancing driven by personal initiatives. Theory: It is possible that the output of protective behaviors, such as adherence to protective measures and staying in social isolation, is influenced by individual characteristics, such as personality traits or symptoms of mental distress of anxiogenic nature. We hypothesized that individuals with more expressive symptoms of fear or anxiety would have a more protective behavioral tendency in terms of risk exposure, leaving less home during the pandemic. In contrast, individuals with greater emotional stability, as they feel more secure and with a lower perception of risk, could go out more often. Method: A total of 2709 individuals from all regions of Brazil participated in the study (mean age = 42 years; 2134 women). Correlation analysis was performed to investigate the relationships between personality traits according to the big five model and Psychopathological Symptoms (BSI). Then, correlation analysis was performed to investigate how people that go out often differ from people that stay at home, in both symptoms and personality traits. Finally, to investigate the predictors for going out usually, we use multiple regression analysis, using gender, marital status, level of education, and personality traits. Results: During the second wave of COVID-19 in Brazil, individuals with higher emotional stability tended to leave home more than those with more expressive levels of anxiogenic dysregulation. These results reinforce the role of both personality traits and psychopathological symptoms in prophylactic behavior during COVID-19 pandemics. Conclusions: Individuals with greater emotional stability were more likely to leave home during the second wave of COVID-19 than those with higher levels of anxiogenic dysregulation.

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The prehistory of the people of Uruguay is greatly complicated by the dramatic and severe effects of European contact, as with most of the Americas. After the series of military campaigns that exterminated the last remnants of nomadic peoples, Uruguayan official history masked and diluted the former Indigenous ethnic diversity into the narrative of a singular people that all but died out. Here, we present the first whole genome sequences of the Indigenous people of the region before the arrival of Europeans, from an archaeological site in eastern Uruguay that dates from 2,000 years before present. We find a surprising connection to ancient individuals from Panama and eastern Brazil, but not to modern Amazonians. This result may be indicative of a migration route into South America that may have occurred along the Atlantic coast. We also find a distinct ancestry previously undetected in South America. Though this work begins to piece together some of the demographic nuance of the region, the sequencing of ancient individuals from across Uruguay is needed to better understand the ancient prehistory and genetic diversity that existed before European contact, thereby helping to rebuild the history of the Indigenous population of what is now Uruguay.

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Mucositis is an inflammation of the gastrointestinal mucosa resulting from high doses of radio/chemotherapy treatment and may lead to interruption of antineoplasic therapy. Soluble fibres, like pectin, increase SCFA production, which play a role in gut homoeostasis and inflammation suppression. Due to the properties of pectin, the aim of the present study was to evaluate the effect of a high-fibre (HF) diet on chemotherapy-induced mucositis in a murine model. C57/BL6 mice received control (AIN93M), HF, low/zero fibre (LF) diets for 10 d prior to mucositis challenging with irinotecan (75 mg/kg), or they were treated with acetate added to drinking water 5 d prior to and during the mucositis induction. Mice that received the HF diet showed decreased immune cells influx and improved histopathological parameters in the intestine, compared with mice that received the normal diet. Furthermore, the HF diet decreased intestinal permeability induced in the mucositis model when compared with the control group. This effect was not observed for acetate alone, which did not improve gut permeability. For instance, mice that received the LF diet had worsened gut permeability, compared with mice that received the normal diet and mucositis. The effects of the HF and LF diets were shown to modulate the intestinal microbiota, in which the LF diet increased the levels of Enterobacteriaceae, a group associated with gut inflammation, whereas the HF diet decreased this group and increased Lactobacillus and Bifidobacterium (SCFA producers) levels. In conclusion, the results demonstrated the importance of dietary fibre intake in the modulation of gut microbiota composition and homoeostasis maintenance during mucositis in this model.

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Since the beginning of the HIV epidemic, research has been carried out to control the virus. Understanding the mechanisms of replication has given access to the various classes of drugs that over time have transformed AIDS into a manageable chronic disease. The class of protease inhibitors (PIs) gained notice in anti-retroviral therapy, once it was found that peptidomimetic molecules act by blocking the active catalytic center of the aspartic protease, which is directly related to HIV maturation. However, mutations in enzymatic internal residues are the biggest issue for these drugs, because a small change in biochemical interaction can generate resistance. Low plasma concentrations of PIs favor viral natural selection; high concentrations can inhibit even partially resistant enzymes. Food-drug/drug-drug interactions can decrease the bioavailability of PIs and are related to many side effects. Therefore, this review summarizes the pharmacokinetic properties of current PIs, the changes when pharmacological boosters are used and also lists the major mutations to help understanding of how long the continuous treatment can ensure a low viral load in patients.

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The repeated observation of dog dung covered by abundant white cottony mycelium in a private garden in the city of Rio de Janeiro, state of Rio de Janeiro (Brazil) prompted an investigation to clarify the identity of the fungus involved. Three different species of mucoralean fungi (together with some ascomycete asexual morphs) were present. Two were identified as belonging to Mycotypha sp. and Thamnostylum sp., and the third belonged to Mucor sp. This publication deals with the full taxonomic elucidation of the latter. Based on morphological, physiological, and molecular data (ITS and LSU rDNA regions), it was recognized that this Mucor differed from all other species. It produces strongly sympodially circinate branched sporangiophores (some with up to four septa) with numerous swellings resembling abortive sporangia. It also has cylindrical, obovoid, pyriform, or ovoid columellae and its sporangiospores are mostly ellipsoid, although some are subglobose and others are irregular. Based on the evidence of the analyzed datasets, the new species Mucor merdophylus is hereby proposed.

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A new species of Hypostomus with spoon-shaped teeth is described from the Rio Cupari basin, a right margin affluent of the lower Rio Tapajós, Pará State, Brazil. The new species inhabits rocky bottom areas in the main channel of Rio Cupari and its tributaries. The new species can be distinguished from all its congeners, except from the Hypostomus cochliodon group, by having six to eight spoon-shaped teeth, dentaries angled at less than 80° and the absence of a notch between the hyomandibular and the metapterygoid. The new species is distinguished from all species of the H. cochliodon group by its unique colour pattern, containing dark vermiculations on head and anterior portion of the trunk, and by the absence of medial buccal papillae.

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The Amazon Basin is an unquestionable biodiversity hotspot, containing the highest freshwater biodiversity on earth and facing off a recent increase in anthropogenic threats. The current knowledge on the spatial distribution of the freshwater fish species is greatly deficient in this basin, preventing a comprehensive understanding of this hyper-diverse ecosystem as a whole. Filling this gap was the priority of a transnational collaborative project, i.e. the AmazonFish project - https://www.amazon-fish.com/. Relying on the outputs of this project, we provide the most complete fish species distribution records covering the whole Amazon drainage. The database, including 2,406 validated freshwater native fish species, 232,936 georeferenced records, results from an extensive survey of species distribution including 590 different sources (e.g. published articles, grey literature, online biodiversity databases and scientific collections from museums and universities worldwide) and field expeditions conducted during the project. This database, delivered at both georeferenced localities (21,500 localities) and sub-drainages grains (144 units), represents a highly valuable source of information for further studies on freshwater fish biodiversity, biogeography and conservation.

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The Atlantic rainforest of Brazil is one of the global terrestrial hotspots of biodiversity. Despite having undergone large scale deforestation, forest cover has shown signs of increases in the last decades. Here, to understand the degradation and regeneration history of Atlantic rainforest remnants near São Paulo, we combine a unique dataset of very high resolution images from Worldview-2 and Worldview-3 (0.5 and 0.3m spatial resolution, respectively), georeferenced aerial photographs from 1962 and use a deep learning method called U-net to map (i) the forest cover and changes and (ii) two pioneer tree species, Cecropia hololeuca and Tibouchina pulchra. For Tibouchina pulchra, all the individuals were mapped in February, when the trees undergo mass-flowering with purple and pink blossoms. Additionally, elevation data at 30m spatial resolution from NASA Shuttle Radar Topography Mission (SRTM) and annual mean climate variables (Terraclimate datasets at ∼ 4km of spatial resolution) were used to analyse the forest and species distributions. We found that natural forests are currently more frequently found on south-facing slopes, likely because of geomorphology and past land use, and that Tibouchina is restricted to the wetter part of the region (southern part), which annually receives at least 1600 mm of precipitation. Tibouchina pulchra was found to clearly indicate forest regeneration as almost all individuals were found within or adjacent to forests regrown after 1962. By contrast, Cecropia hololeuca was found to indicate older disturbed forests, with all individuals almost exclusively found in forest fragments already present in 1962. At the regional scale, using the dominance maps of both species, we show that at least 4.3% of the current region's natural forests have regrown after 1962 (Tibouchina dominated, ∼ 4757 ha) and that ∼ 9% of the old natural forests have experienced significant disturbance (Cecropia dominated).

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Brainstem cavernous malformations are frequently surrounded by vital structures, which often makes surgical treatment a challenging task even to the most skilled surgeon. Accordingly, microsurgical excision is preferably offered to symptomatic patients and superficial lesions.1-3 We present the case of a 41-yr-old male presenting with progressive dizziness and diplopia. Neurological examination showed horizontal nystagmus, dysmetria, and unbalance. Preoperative magnetic resonance imaging (MRI) suggested a cavernous malformation in the right middle cerebellar peduncle. A telovelar approach was employed with the guidance of intraoperative neurophysiological monitoring. An exophytic lesion was identified in the right middle cerebellar peduncle and a clear cleavage plane was obtained allowing circumferential dissection around the capsule. The lesion was removed en bloc. Postoperative MRI confirmed a complete excision of the malformation. The patient presented an improvement in his initial symptoms, with no new neurological deficit. Cavernous malformations related with the fourth ventricle can be successfully resected through a telovelar approach in select cases, especially when exophytic, where the surgeon might take advantage of the path created by the lesion. Informed consent was obtained from the patient for the procedure and publication of this operative video. Anatomic images were a courtesy of the Rhoton Collection, American Association of Neurological Surgeons (AANS)/Neurosurgical Research and Education Foundation (NREF).

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BACKGROUND: The use of agro-industrial wastes to produce high value-added biomolecules such as biosurfactants is a promising approach for lowering the total costs of production. This study aimed to produce biosurfactants using Rhizopus arrhizus UCP 1607, with crude glycerol (CG) and corn steep liquor (CSL) as substrates. In addition, the biomolecule was characterized, and its efficiency in removing petroderivatives from marine soil was investigated. RESULTS: A 22 factorial design was applied, and the best condition for producing the biosurfactant was determined in assay 4 (3% CG and 5% CSL). The biosurfactant reduced the surface tension of water from 72 to 28.8 mN/m and produced a yield of 1.74 g/L. The preliminary biochemical characterization showed that the biosurfactant consisted of proteins (38.0%), carbohydrates (35.4%), and lipids (5.5%). The compounds presented an anionic character, nontoxicity, and great stability for all conditions tested. The biomolecule displayed great ability in dispersing hydrophobic substrates in water, thereby resulting in 53.4 cm2 ODA. The best efficiency of the biosurfactant in removing the pollutant diesel oil from marine soil was 79.4%. CONCLUSIONS: This study demonstrated the ability of R. arrhizus UCP1607 to produce a low-cost biosurfactant characterized as a glycoprotein and its potential use in the bioremediation of the hydrophobic diesel oil pollutant in marine soil

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Clearance and perturbation of Amazonian forests are one of the greatest threats to tropical biodiversity conservation of our times. A better understanding of how soil communities respond to Amazonian deforestation is crucially needed to inform policy interventions that effectively protect biodiversity and the essential ecosystem services it provides. We assessed the impact of deforestation and ecosystem conversion to arable land on Amazonian soil biodiversity through a meta-analysis. We analyzed 274 pairwise comparisons of soil biodiversity in Amazonian primary forests and sites under different stages of deforestation and land-use conversion: disturbed (wildfire and selective logging) and slash-and-burnt forests, pastures, and cropping systems. Overall, 60% and 51% of responses of soil macrofauna and microbial community attributes (i.e., abundance, biomass, richness, and diversity indexes) to deforestation were negative, respectively. We found few studies on mesofauna (e.g., microarthropods) and microfauna (e.g., protozoa and nematodes), so those groups could not be analyzed. Macrofauna abundance and biomass were more vulnerable to the displacement of forests by pastures than by agricultural fields, whereas microbes showed the opposite pattern. Effects of Amazonian deforestation on macrofauna were more detrimental at sites with mean annual precipitation >1900 mm, and higher losses of microbes occurred in highly acidic soils (pH < 4.5). Limited geographic coverage, omission of meso- and microfauna, and low taxonomic resolution were main factors impairing generalizations from the data set. Few studies assessed the impacts of within-forest disturbance (wildfires and selective logging) on soil species in Amazonia, where logging operations rapidly expand across public lands and more frequent severe dry seasons are increasing the prevalence of wildfires.

Deforestación en el Amazonas y Biodiversidad del Suelo Resumen Actualmente, el despeje y la perturbación de los bosques del Amazonas son las principales amenazas para la conservación de la biodiversidad tropical. Se requiere urgentemente de un mejor entendimiento sobre cómo las comunidades del suelo responden a la deforestación amazónica para informar a las intervenciones políticas que protegen efectivamente a la biodiversidad y a los servicios ambientales esenciales que proporciona. Evaluamos el impacto de la deforestación y la conversión del ecosistema a suelo arable sobre la biodiversidad del suelo amazónico por medio de un meta-análisis. Analizamos 274 comparaciones por pares de la biodiversidad del suelo amazónico en bosques primarios y sitios bajo diferentes etapas de deforestación y conversión de uso de suelo: bosques perturbados (incendios forestales y tala selectiva) y de corte-y-quema, pasturas, y sistemas agrícolas. En general, el 60% y el 51% de las respuestas de los atributos (es decir, abundancia, biomasa, riqueza, e índices de biodiversidad) de la macrofauna del suelo y de las comunidades microbianas ante la deforestación fueron negativas, respectivamente. Encontramos pocos estudios sobre la mesofauna (p. ej.: microartrópodos) y la microfauna (p. ej.: protozoarios y nematodos), así que estos grupos no pudieron ser analizados. La abundancia de la macrofauna y la biomasa fueron más vulnerables al desplazamiento de bosques por las pasturas que por los campos agrícolas, mientras que los microbios mostraron el patrón opuesto. Los efectos de la deforestación amazónica sobre la macrofauna fueron más dañinos en sitios con una precipitación anual media mayor a los 1,900 mm, y ocurrieron pérdidas más elevadas de microbios en suelos con una acidez alta (pH < 4.5). La cobertura geográfica limitada, la omisión de la mesofauna y la microfauna, y la baja resolución taxonómica fueron los factores principales que obstaculizaron las generalizaciones del conjunto de datos. Pocos estudios evaluaron los impactos de las perturbaciones internas del bosque (incendios forestales y tala selectiva) sobre las especies del suelo amazónico, a la vez que las operaciones de tala se expanden rápidamente en los terrenos públicos y la ocurrencia con mayor frecuencia de temporadas con sequía grave aumentan la prevalencia de los incendios forestales.

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Frutalin is a galactose-binding lectin that has an irreversible cytotoxic effect on HeLa cervical cancer cells, by inducing apoptosis and inhibiting cell proliferation. It was previously shown that after in vitro incubation, frutalin is internalized into HeLa cells nucleus, which indicates that frutalin apoptosis-inducing activity might be linked with its nuclear localization. Considering that drugs commonly used for cancer treatment have a deleterious effect on germ cells, the aim of this study was to evaluate the effect of frutalin on the activation, survival, ultrastructure and gene expression in follicles cultured within ovarian tissue. Goat ovarian fragments were cultured for 6 days in α-MEM⁺ alone or supplemented with frutalin (1, 10, 50, 100 or 200 µg/ml). Non-culturad and cultured tissues were processed for histological and ultrastructural analysis and they were also stored to evaluate the expression of anti- and pro-apoptotic genes by quantitative polymerase chain reaction (qPCR). The results showed that the frutalin, at all concentrations tested, reduced follicular survival when compared with control medium. Higher concentrations of frutalin (50, 100 or 200 µg/ml) also reduced follicular survival when compared with those tissues cultured with 1 or 10 µg/ml of frutalin. The ultrastructural analysis showed that atretic cultured follicles had retracted oocytes and a large number of vacuoles spread throughout the cytoplasm. In addition, signs of damage of mitochondrial membranes and cristae were observed. Moreover, although a dose-response effect on gene expression has not been observed, when compared with tissues culture in control medium, the presence of frutalin increased in mRNA expression pro-apoptotic genes. In conclusion, frutalin reduces follicular survival at all concentrations tested, its effects being more pronounced when high concentrations of this lectin (50, 100 and 200 µg/ml) are used. Gene expression profile and ultrastrutural features of cultured follicles suggest that follicular death in goat ovarian tissue cultured in presence of frutalin occurs via necrosis.

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BACKGROUND:: Cardiac Magnetic Resonance is in need of a simple and robust method for diastolic function assessment that can be done with routine protocol sequences. OBJECTIVE:: To develop and validate a three-dimensional (3D) model-based volumetric assessment of diastolic function using cardiac magnetic resonance (CMR) imaging and compare the results obtained with the model with those obtained by echocardiography. METHODS:: The study participants provided written informed consent and were included if having undergone both echocardiography and cine steady-state free precession (SSFP) CMR on the same day. Guide points at the septal and lateral mitral annulus were used to define the early longitudinal relaxation rate (E'), while a time-volume curve from the 3D model was used to assess diastolic filling parameters. We determined the correlation between 3D CMR and echocardiography and the accuracy of CMR in classifying the diastolic function grade. RESULTS:: The study included 102 subjects. The E/A ratio by CMR was positively associated with the E/A ratio by echocardiography (r = 0.71, p < 0.0001). The early diastolic relaxation velocity by tissue Doppler and longitudinal relaxation rate for the lateral mitral annulus displacement were positively associated (p = 0.007), as were the ratio between Doppler E/e' and CMR E/E' (p = 0.01). CMR-determined normalized peak E (NE) and deceleration time (DT) were able to predict diastolic dysfunction (areas under the curve [AUCs] = 0.70 and 0.72, respectively). In addition, the lateral E/E' ratio showed good utility in identifying diastolic dysfunction (AUC = 0.80). Overall, echocardiography and CMR interobserver and intraobserver agreements were excellent (intraclass correlation coefficient range 0.72 - 0.97). CONCLUSION:: 3D modeling of standard cine CMR images was able to identify study subjects with reduced diastolic function and showed good reproducibility, suggesting a potential for a routine diastolic function assessment by CMR. FUNDAMENTO:: A ressonância magnética cardíaca necessita de um método simples e robusto para a avaliação da função diastólica que pode ser feito com sequências protocolares de rotina. OBJETIVO:: Desenvolver e validar a avaliação volumétrica da função diastólica através de um modelo tridimensional (3D) com utilização de imagens de ressonância magnética cardíaca (RMC) e comparar os resultados obtidos com este modelo com os obtidos por ecocardiografia. MÉTODOS:: Os participantes do estudo assinaram um termo de consentimento e foram incluídos se tivessem sido submetidos no mesmo dia tanto à ecocardiografia quanto à cine RMC com precessão livre no estado estacionário (steady-state free precession, SSFP). Pontos-guia foram utilizados no anel mitral septal e lateral para definir a velocidade de estiramento no início da diástole (E'), enquanto curvas de volume-tempo do modelo 3D foram utilizadas para avaliar os parâmetros de enchimento diastólico. Foram determinadas a correlação entre a RMC 3D e a ecocardiografia, além da acurácia da RMC em classificar o grau de função diastólica. RESULTADOS:: Ao todo, 102 sujeitos foram incluídos no estudo. A razão E/A pela RMC esteve positivamente associada com a razão E/A obtida pela ecocardiografia (r = 0,71, p < 0,0001). Estiveram positivamente associadas a velocidade de relaxamento diastólico inicial ao Doppler tecidual e a velocidade de relaxamento longitudinal de deslocamento do anel mitral lateral (p = 0,007), bem como a razão entre E/e' por Doppler e E/E' pela RMC (p = 0,01). A velocidade normalizada de pico de enchimento (EM) determinada pela RMC e o tempo de desaceleração (TD) foram capazes de predizer a disfunção diastólica (áreas sob a curva [AUCs] = 0,70 e 0,72, respectivamente). Além disso, a razão E/E' lateral mostrou boa utilidade para a identificação da disfunção diastólica (AUC = 0,80). No geral, a ecocardiografia e a RMC apresentaram excelente concordância interobservador e intraobservador (coeficiente de correlação intraclasse 0,72 - 0,97). CONCLUSÃO:: Uma modelagem 3D de imagens padrões de cine RMC foi capaz de identificar os indivíduos do estudo com função diastólica reduzida e mostrou uma boa reprodutibilidade, sugerindo ter potencial na avaliação rotineira da função diastólica por RMC.

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Abstract Background: Cardiac Magnetic Resonance is in need of a simple and robust method for diastolic function assessment that can be done with routine protocol sequences. Objective: To develop and validate a three-dimensional (3D) model-based volumetric assessment of diastolic function using cardiac magnetic resonance (CMR) imaging and compare the results obtained with the model with those obtained by echocardiography. Methods: The study participants provided written informed consent and were included if having undergone both echocardiography and cine steady-state free precession (SSFP) CMR on the same day. Guide points at the septal and lateral mitral annulus were used to define the early longitudinal relaxation rate (E'), while a time-volume curve from the 3D model was used to assess diastolic filling parameters. We determined the correlation between 3D CMR and echocardiography and the accuracy of CMR in classifying the diastolic function grade. Results: The study included 102 subjects. The E/A ratio by CMR was positively associated with the E/A ratio by echocardiography (r = 0.71, p < 0.0001). The early diastolic relaxation velocity by tissue Doppler and longitudinal relaxation rate for the lateral mitral annulus displacement were positively associated (p = 0.007), as were the ratio between Doppler E/e' and CMR E/E' (p = 0.01). CMR-determined normalized peak E (NE) and deceleration time (DT) were able to predict diastolic dysfunction (areas under the curve [AUCs] = 0.70 and 0.72, respectively). In addition, the lateral E/E' ratio showed good utility in identifying diastolic dysfunction (AUC = 0.80). Overall, echocardiography and CMR interobserver and intraobserver agreements were excellent (intraclass correlation coefficient range 0.72 - 0.97). Conclusion: 3D modeling of standard cine CMR images was able to identify study subjects with reduced diastolic function and showed good reproducibility, suggesting a potential for a routine diastolic function assessment by CMR.

Resumo Fundamento: A ressonância magnética cardíaca necessita de um método simples e robusto para a avaliação da função diastólica que pode ser feito com sequências protocolares de rotina. Objetivo: Desenvolver e validar a avaliação volumétrica da função diastólica através de um modelo tridimensional (3D) com utilização de imagens de ressonância magnética cardíaca (RMC) e comparar os resultados obtidos com este modelo com os obtidos por ecocardiografia. Métodos: Os participantes do estudo assinaram um termo de consentimento e foram incluídos se tivessem sido submetidos no mesmo dia tanto à ecocardiografia quanto à cine RMC com precessão livre no estado estacionário (steady-state free precession, SSFP). Pontos-guia foram utilizados no anel mitral septal e lateral para definir a velocidade de estiramento no início da diástole (E'), enquanto curvas de volume-tempo do modelo 3D foram utilizadas para avaliar os parâmetros de enchimento diastólico. Foram determinadas a correlação entre a RMC 3D e a ecocardiografia, além da acurácia da RMC em classificar o grau de função diastólica. Resultados: Ao todo, 102 sujeitos foram incluídos no estudo. A razão E/A pela RMC esteve positivamente associada com a razão E/A obtida pela ecocardiografia (r = 0,71, p < 0,0001). Estiveram positivamente associadas a velocidade de relaxamento diastólico inicial ao Doppler tecidual e a velocidade de relaxamento longitudinal de deslocamento do anel mitral lateral (p = 0,007), bem como a razão entre E/e' por Doppler e E/E' pela RMC (p = 0,01). A velocidade normalizada de pico de enchimento (EM) determinada pela RMC e o tempo de desaceleração (TD) foram capazes de predizer a disfunção diastólica (áreas sob a curva [AUCs] = 0,70 e 0,72, respectivamente). Além disso, a razão E/E' lateral mostrou boa utilidade para a identificação da disfunção diastólica (AUC = 0,80). No geral, a ecocardiografia e a RMC apresentaram excelente concordância interobservador e intraobservador (coeficiente de correlação intraclasse 0,72 - 0,97). Conclusão: Uma modelagem 3D de imagens padrões de cine RMC foi capaz de identificar os indivíduos do estudo com função diastólica reduzida e mostrou uma boa reprodutibilidade, sugerindo ter potencial na avaliação rotineira da função diastólica por RMC.

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Land use changes (LUC) from pasture to sugarcane (Saccharum spp.) crop are expected to add 6.4Mha of new sugarcane land by 2021 in the Brazilian Cerrado and Atlantic Forest biomes. We assessed the effects of these LUC on the abundance and community structure of animals that inhabit soils belowground through a field survey using chronosequences of land uses comprising native vegetation, pasture, and sugarcane along a 1000-km-long transect across these two major tropical biomes in Brazil. Macrofauna community composition differed among land uses. While most groups were associated with samples taken in native vegetation, high abundance of termites and earthworms appeared associated with pasture soils. Linear mixed effects analysis showed that LUC affected total abundance (X(2)(1)=6.79, p=0.03) and taxa richness (X(2)(1)=6.08, p=0.04) of soil macrofauna. Abundance increased from 411±70individualsm(-2) in native vegetation to 1111±202individualsm(-2) in pasture, but decreased sharply to 106±24individualsm(-2) in sugarcane soils. Diversity decreased 24% from native vegetation to pasture, and 39% from pasture to sugarcane. Thus, a reduction of ~90% in soil macrofauna abundance, besides a loss of ~40% in the diversity of macrofauna groups, can be expected when sugarcane crops replace pasture in Brazilian tropical soils. In general, higher abundances of major macrofauna groups (ants, coleopterans, earthworms, and termites) were associated with higher acidity and low contents of macronutrients and organic matter in soil. This study draws attention for a significant biodiversity loss belowground due to tropical LUC in sugarcane expansion areas. Given that many groups of soil macrofauna are recognized as key mediators of ecosystem processes such as soil aggregation, nutrients cycling and soil carbon storage, our results warrant further efforts to understand the impacts of altering belowground biodiversity and composition on soil functioning and agriculture performance across LUC in the tropics.

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Increasing demand for biofuel has intensified land-use change (LUC) for sugarcane (Saccharum officinarum) expansion in Brazil. Assessments of soil quality (SQ) response to this LUC are essential for quantifying and monitoring sustainability of sugarcane production over time. Since there is not a universal methodology for assessing SQ, we conducted a field-study at three sites within the largest sugarcane-producing region of Brazil to develop a SQ index (SQI). The most common LUC scenario (i.e., native vegetation to pasture to sugarcane) was evaluated using six SQI strategies with varying complexities. Thirty eight soil indicators were included in the total dataset. Two minimum datasets were selected: one using principal component analysis (7 indicators) and the other based on expert opinion (5 indicators). Non-linear scoring curves were used to interpret the indicator values. Weighted and non-weighted additive methods were used to combine individual indicator scores into an overall SQI. Long-term conversion from native vegetation to extensive pasture significantly decreased overall SQ. In contrast, conversion from pasture to sugarcane had no significant impact on overall SQ at the regional scale, but site-specific responses were found. In general, sugarcane production improved chemical attributes (i.e., higher macronutrient levels and lower soil acidity); however it has negative effects on physical and biological attributes (i.e., higher soil compaction and structural degradation as well as lower soil organic carbon (SOC), abundance and diversity of macrofauna and microbial activity). Overall, we found that simple, user-friendly strategies were as effective as more complex ones for identifying SQ changes. Therefore, as a protocol for SQ assessments in Brazilian sugarcane areas, we recommend using a small number of indicators (e.g., pH, P, K, Visual Evaluation of Soil Structure -VESS scores and SOC concentration) and proportional weighting to reflect chemical, physical and biological processes within the soil. Our SQ evaluations also suggest that current approaches for expanding Brazilian sugarcane production by converting degraded pasture land to cropland can be a sustainable strategy for meeting increasing biofuel demand. However, management practices that alleviate negative impacts on soil physical and biological indicators must be prioritized within sugarcane producing areas to prevent unintentional SQ degradation over time.

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