Summary
Imbalances in the gut microbiota, the bacteria that inhabit the intestines, are central to the pathogenesis of obesity. This systematic review assesses the association between the gut ...microbiota and weight loss in overweight/obese adults and its potential manipulation as a target for treating obesity. This review identified 43 studies using the keywords ‘overweight’ or ‘obesity’ and ‘microbiota’ and related terms; among these studies, 17 used dietary interventions, 11 used bariatric surgery and 15 used microbiota manipulation. The studies differed in their methodologies as well as their intervention lengths. Restrictive diets decreased the microbiota abundance, correlated with nutrient deficiency rather than weight loss and generally reduced the butyrate producers Firmicutes, Lactobacillus sp. and Bifidobacterium sp. The impact of surgical intervention depended on the given technique and showed a similar effect on butyrate producers, in addition to increasing the presence of the Proteobacteria phylum, which is related to changes in the intestinal absorptive surface, pH and digestion time. Probiotics differed in strain and duration with diverse effects on the microbiota, and they tended to reduce body fat. Prebiotics had a bifidogenic effect and increased butyrate producers, likely due to cross‐feeding interactions, contributing to the gut barrier and improving metabolic outcomes. All of the interventions under consideration had impacts on the gut microbiota, although they did not always correlate with weight loss. These results show that restrictive diets and bariatric surgery reduce microbial abundance and promote changes in microbial composition that could have long‐term detrimental effects on the colon. In contrast, prebiotics might restore a healthy microbiome and reduce body fat.
We present a study of 33 Kepler planet-candidate host stars for which asteroseismic observations have sufficiently high signal-to-noise ratio to allow extraction of individual pulsation frequencies. ...We implement a new Bayesian scheme that is flexible in its input to process individual oscillation frequencies, combinations of them, and average asteroseismic parameters, and derive robust fundamental properties for these targets. Applying this scheme to grids of evolutionary models yields stellar properties with median statistical uncertainties of 1.2 per cent (radius), 1.7 per cent (density), 3.3 per cent (mass), 4.4 per cent (distance), and 14 per cent (age), making this the exoplanet host-star sample with the most precise and uniformly determined fundamental parameters to date. We assess the systematics from changes in the solar abundances and mixing-length parameter, showing that they are smaller than the statistical errors. We also determine the stellar properties with three other fitting algorithms and explore the systematics arising from using different evolution and pulsation codes, resulting in 1 per cent in density and radius, and 2 per cent and 7 per cent in mass and age, respectively. We confirm previous findings of the initial helium abundance being a source of systematics comparable to our statistical uncertainties, and discuss future prospects for constraining this parameter by combining asteroseismology and data from space missions. Finally, we compare our derived properties with those obtained using the global average asteroseismic observables along with effective temperature and metallicity, finding excellent level of agreement. Owing to selection effects, our results show that the majority of the high signal-to-noise ratio asteroseismic Kepler host stars are older than the Sun.
AbstractAdding fiber to reinforce soil is a technique widely used at geotechnical works due to the possibility of a considerable increase in soil’s mechanical properties. One way to evaluate such ...improvement is to compare the features before and after the addition, utilizing the unconfined compressive strength (UCS) test. However, the results of this test can be biased by soil variability, fibers characteristics, and test errors. The objective of the present work is to analyze which variable most influences the results of UCS tests and evaluate the relationship between the soil strain and its strength alterations due to fiber. In this way, the extended chi-square automatic interaction detector (CHAID) method was adopted on UCS samples obtained from a database established from papers, theses, and dissertations. This process concluded that the type of fiber used is the variable with the highest significance among the studied ones. Furthermore, the regression of the polypropylene (PP) demonstrated a linear tendency and a strong correlation coefficient, validating the hypothesis that the sample’s strength has an immediate relation with its strain.
Ecosystem restoration is a global priority, currently promoted by several ambitious commitments. Most of the research to guide restoration practices was so far put on the recovery of above‐ground ...functions and services, although soil health is increasingly recognized as a fundamental condition to restoration success. Soil restoration is particularly needed in mining areas, in which the surface soil layers are removed and the left over, highly deprived substrate does not support vegetation recovery.
Here, we evaluated the potential of active restoration to recover soil attributes after bauxite mining in the Brazil's Atlantic Forest. We specifically studied how physical, chemical and microbiological soil attributes down to 40 cm depth respond to restoration (i.e. topsoil spreading and tree planting) by comparing newly mined areas, areas undergoing restoration for ~7 years and conserved forests. We further explored the associations between microbiological and physico‐chemical soil attributes.
Restoration interventions resulted in a 10‐fold increase in the soil organic matter content compared to mined areas, as well as in the recovery of P content. Restoration was also shown to be associated with the recovery of the activity and diversity of soil bacterial communities, reaching similar levels to those observed in conserved forest. Restored and conserved forests were characterized by a higher proportion of Acidobacteria, Planctomycetes and Verrucomicrobia. All bacterial attributes were correlated with soil physical attributes, except for microporosity, and with organic matter and cation exchange capacity.
Within a few years, restoration allowed recovering crucial physical, chemical and microbiological soil attributes, reaching levels comparable to those found in conserved forests.
Synthesis and applications. We demonstrate that intensive management can result in the fast restoration of tropical forest soils after mining, at least at small scales. Our results stress the need to consider soil recovery both as a driver and a measure of ecosystem restoration success, and support the development of more holistic monitoring protocols to be used during the United Nations Decade on Ecosystem Restoration.
Resumo
A restauração de ecossistemas é uma prioridade global, atualmente promovida por vários compromissos ambiciosos. A maior parte da pesquisa para orientar as práticas de restauração foi até agora focada na recuperação de funções e serviços acima do solo, embora a saúde do solo seja cada vez mais reconhecida como uma condição fundamental para o sucesso da restauração. A restauração do solo é particularmente necessária em áreas de mineração, nas quais as camadas superficiais do solo são removidas e o substrato que sobra, altamente degradado, não suporta a recuperação da vegetação.
Neste estudo, avaliamos o potencial da restauração ativa para recuperar atributos do solo após a mineração de bauxita na Mata Atlântica do Brasil. Nós estudamos especificamente como os atributos físicos, químicos e microbiológicos do solo respondem à restauração até 40 cm de profundidade (ou seja, espalhamento de topsoil e plantio de árvores), comparando áreas recém‐mineradas, áreas em restauração por ~ 7 anos e florestas conservadas. Exploramos ainda as associações entre atributos microbiológicos e físico‐químicos do solo.
As intervenções de restauração resultaram em um aumento de 10 vezes no teor de matéria orgânica do solo em relação às áreas mineradas, bem como na recuperação do teor de P. A restauração também se mostrou associada à recuperação da atividade e diversidade das comunidades bacterianas do solo, atingindo níveis semelhantes aos observados nas florestas conservadas. Florestas restauradas e conservadas foram caracterizadas por uma maior proporção de Acidobacteria, Planctomycetes e Verrucomicrobia. Todos os atributos bacterianos foram correlacionados com os atributos físicos do solo, exceto com a microporosidade, e com matéria orgânica e capacidade de troca catiônica.
Em poucos anos, a restauração permitiu a recuperação de atributos físicos, químicos e microbiológicos cruciais do solo, atingindo níveis comparáveis aos encontrados em florestas conservadas.
Síntese e aplicações. Demonstramos que o manejo intensivo pode resultar na rápida restauração dos solos da floresta tropical após a mineração, pelo menos em pequena escala. Nossos resultados enfatizam a necessidade de considerar a recuperação do solo tanto como um impulsionador e uma medida do sucesso da restauração de ecossistemas, e para apoiar o desenvolvimento de protocolos de monitoramento mais holísticos a serem usados durante a Década das Nações Unidas para a Restauração de Ecossistemas.
We demonstrate that intensive management can result in the fast restoration of tropical forest soils after mining, at least at small scales. Our results stress the need to consider soil recovery both as a driver and a measure of ecosystem restoration success, and support the development of more holistic monitoring protocols to be used during the United Nations Decade on Ecosystem Restoration.
Lymphoma is the most important haemopoietic tumour in cats and has been associated with feline leukaemia virus (FeLV) infection. In Brazil, no studies have established a correlation between FeLV ...infection and lymphoma. The aim of this study was to characterize lymphomas arising in cats in Brazil anatomically and microscopically, and to correlate these data with FeLV infection as determined by immunohistochemistry for the FeLV gp70 antigen. Fifty-three cats with lymphoma were evaluated. The mean age of junior, prime, mature, senior and geriatric cats was 1.65 years, 4.34 years, 8 years, 12.14 years and 15.5 years, respectively. The anatomical types of lymphoma were multicentric (43.4%, 23/53), mediastinal (33.96%, 18/53), renal (11.32%, 6/53), hepatic (5.66%, 3/53), nodal (3.77%, 2/53) and alimentary (1.89 %, 1/53). The histological types were small noncleaved-cell (33.96%, 18/53), mixed diffuse (22.64%, 12/53), immunoblastic (15.11%, 8/53), lymphoblastic (11, 32%, 6/53), small lymphocytic (9.43%, 5/53), small cleaved-cell (3.77%, 2/53) and large cell lymphomas (3.77%, 2/3). Immunopositivity for FeLV was observed in 56.6% (30/53) of the samples. FeLV positivity was equally distributed between the genders, but predominated in junior and prime cats. The degree of association between lymphoma and FeLV infection in Brazil was higher than that found in other countries, demonstrating the need to prevent and control the factors associated with infection.
Leukaemia is a haemopoietic neoplasm originating from myeloid or lymphoid precursors in the bone marrow and may be either acute or chronic. These tumours are rare, but occur more frequently in cats ...because of an association with the feline leukaemia virus (FeLV) and feline immunodeficiency virus (FIV). To the best of our knowledge, no studies conducted in Brazil to date have analysed the association between leukaemia and FeLV and FIV infection in cats. The aim of this study was to perform a histopathological analysis of feline leukaemia and evaluate the association between leukaemia and FeLV and FIV infection in cats. The study evaluated 37 cats with leukaemia diagnosed between 2009 and 2017. The animals underwent necropsy examination, histopathology and immunohistochemistry with anti-FeLV gp70 and anti-FIV p24 gag antibodies. Of the evaluated animals, 54% (20/37) were males and 43.2% (16/37) were females. With respect to the life stage of the animals, 24.3% (9/37) were junior, 32.4% (12/37) were prime, 18.9% (7/37) were mature and 10.8% (4/37) were senior, and five animals were of unknown age. Myeloid leukaemia occurred in 56.8% (21/37) of the cases and lymphocytic leukaemia occurred in 43.2% (16/37) of the cases. Acute leukaemia (73%, 27/37) was more common than chronic leukaemia (27%, 10/37). The positivity for FeLV (78.4%, 29/37) and FIV (16.2%, 6/37) indicated a high association between FeLV infection and tumour development in the study region.
Using asteroseismic data and stellar evolution models we obtain the first detection of a convective core in a Kepler field main-sequence star, putting a stringent constraint on the total size of the ...mixed zone and showing that extra mixing beyond the formal convective boundary exists. In a slightly less massive target the presence of a convective core cannot be conclusively discarded, and thus its remaining main-sequence lifetime is uncertain. Our results reveal that best-fit models found solely by matching individual frequencies of oscillations corrected for surface effects do not always properly reproduce frequency combinations. Moreover, slightly different criteria to define what the best-fit model is can lead to solutions with similar global properties but very different interior structures. We argue that the use of frequency ratios is a more reliable way to obtain accurate stellar parameters, and show that our analysis in field main-sequence stars can yield an overall precision of 1.5%, 4%, and 10% in radius, mass, and age, respectively. We compare our results with those obtained from global oscillation properties, and discuss the possible sources of uncertainties in asteroseismic stellar modeling where further studies are still needed.
The selection of parents to originate promising base populations, as well as the knowledge of the gene effects controlling agronomic traits by means of diallel, are useful to drive genetic gains in ...Brazilian tropical wheat breeding programs. The goals of this study were to select tropical wheat parents with a high frequency of favorable alleles and segregating populations with high potential to originate superior progenies through partial diallel analysis. Thus, 14 parents were divided in two groups and crossed in a 7 × 7 partial diallel scheme to originate 49 F1 combinations. After obtaining F2 generation, the populations and the parents were evaluated in the field in the summer of 2021. Days for heading, plant height, rust and yellow spot resistance, and grain yield were evaluated. The data were subjected to partial diallel analysis. There were significant effects of general combining ability for all traits. The specific combining ability effect was significant for days for heading and plant height. The additive gene effects were predominant over the non-additive ones. The parents with the highest frequency of favorable alleles for the traits evaluated were selected in each group. Four populations with high genetic potential to originate superior progenies were selected.
In soil sciences, parametric models known as constitutive models (e.g., the Modified Cam Clay and the NorSand) are used to represent the behavior of natural and artificial materials. In contexts ...where liquefaction may occur, the NorSand constitutive model has been extensively applied by both industry and academia due to its relatively simple critical state formulation and low number of input parameters. Despite its suitability as a good modeling framework to assess static liquefaction, the NorSand model still is based on premises which may not perfectly represent the behavior of all soil types. In this context, the creation of data-driven and physically informed metamodels emerges. The literature suggests that data-driven models should initially be developed using synthetic datasets to establish a general framework, which can later be applied to experimental datasets to enhance the model's robustness and aid in discovering potential mechanisms of soil behavior. Therefore, creating large and reliable synthetic datasets is a crucial step in constructing data-driven constitutive models. In this context, the NorSand model comes in handy: by using NorSand simulations as the training dataset, data-driven constitutive metamodels can then be fine-tuned using real test results. The models created that way will combine the power of NorSand with the flexibility provided by data-driven approaches, enhancing the modeling capabilities for liquefaction. Therefore, for a material following the NorSand model, the present paper presents a first-of-its-kind database that addresses the size and complexity issues of creating synthetic datasets for nonlinear constitutive modeling of soils by simulating both drained and undrained triaxial tests. Two datasets are provided: the first one considers a nested Latin hypercube sampling of input parameters encompassing 2000 soil types, each subjected to 40 initial test configurations, resulting in a total of 160 000 triaxial test results. The second one considers nested quasi-Monte Carlo sampling techniques (Sobol and Halton) of input parameters encompassing 2048 soil types, each subjected to 42 initial test configurations, resulting in a total of 172 032 triaxial test results. By using the quasi-Monte Carlo dataset and 49 of its subsamples, it is shown that the dataset of 2000 soil types and 40 initial test configurations is sufficient to represent the general behavior of the NorSand model. In this process, four machine learning algorithms (Ridge Regressor, KNeighbors Regressor and two variants of the Ridge Regressor which incorporate nonlinear Nystroem kernel mappings of the input and output values) were trained to predict the constitutive and test parameters based solely on the triaxial test results. These algorithms achieved 13.91 % and 16.18 % mean absolute percentage errors among all 14 predicted parameters for undrained and drained triaxial test inputs, respectively. As a secondary outcome, this work introduces a Python script that links the established Visual Basic implementation of NorSand to the Python environment. This enables researchers to leverage the comprehensive capabilities of Python packages in their analyses related to this constitutive model.
Abstract This study aimed to determine whether the addition of green propolis extract to the diet of laying hens would improve egg quality and bird performance and decrease bacterial contamination of ...eggs. Forty-five brown Hy-line laying hens were used, divided into five groups with three replicates each and three animals per cage: T0 - diet without propolis; T5 - 5 grams of propolis per kg of feed; T10 - 10 grams of propolis per kg of feed; T20 - 20 grams of propolis per kg of feed and T30 - 30 grams of propolis per kg of feed. The quality of fresh eggs was made on day 21 of the experiment, and eggs were stored for 21 days. Greater specific gravity was observed in fresh eggs in T5 birds and stored eggs for T10. TBARS in fresh eggs, we found that T30 eggs had lower levels compared to other treatments. T20 eggs had the lowest total bacterial count and the lowest total coliform count in the eggshells of T10 and T20 chickens. The count of E. coli in the peel was lower for T20 and T30 than T0 and T5. The consumption of propolis did not interfere with the hens’ egg production rate but reduced food intake and consequently reduced feed conversion. We concluded that the addition of green propolis in the diet of laying birds proved efficient in reducing bacterial contamination in the eggshells and reducing the lipid peroxidation of fresh and stored eggs.