355 research outputs found
Modified Brans-Dicke theory of gravity from five-dimensional vacuum
We investigate, in the context of five-dimensional (5D) Brans-Dicke theory of
gravity, the idea that macroscopic matter configurations can be generated from
pure vacuum in five dimensions, an approach first proposed in the framework of
general relativity. We show that the 5D Brans-Dicke vacuum equations when
reduced to four dimensions lead to a modified version of Brans-Dicke theory in
four dimensions (4D). As an application of the formalism, we obtain two
five-dimensional extensions of four-dimensional O'Hanlon and Tupper vacuum
solution and show that they lead two different cosmological scenarios in 4D.Comment: 9 page
The role of serum levels of vitamin D in children’s muscle strength: A systematic review
This review aims to investigate the different levels of vitamin D and its role in muscle strength in healthy children and non-athletes. A search conducted in three databases (PubMed, Scopus, and Psycinfo) resulted in 655 articles, which were systematically analyzed and selected based on the following criteria: (a) original cross-sectional studies and clinical trials; (b) healthy children aged 5-11 years; (c) no language restriction or year of publication; and (d) studies that assessed the possible relationship between vitamin D levels and muscle strength. Six studies were included because they met all the inclusion criteria. According to the findings of this review, factors such as sex, skin color, and vitamin D supplementation early in life modulate the levels of vitamin D in the body, and there is a relationship between muscle strength and vitamin D levels. Interestingly, vitamin D supplementation is not always significantly associated with increased muscle grip strength. However, there is a scarcity of studies that aim to analyze the possible effects of different levels of vitamin D on muscle function and neuromuscular variables in physically inactive children and non-athletes without previously diagnosed disease. Further studies are warranted in the future to address the gap in the literature
Altered glucose homeostasis and hepatic function in obese mice deficient for both kinin receptor genes
The Kallikrein-Kinin System (KKS) has been implicated in several aspects of metabolism, including the regulation of glucose homeostasis and adiposity. Kinins and des-Arg-kinins are the major effectors of this system and promote their effects by binding to two different receptors, the kinin B2 and B1 receptors, respectively. To understand the influence of the KKS on the pathophysiology of obesity and type 2 diabetes (T2DM), we generated an animal model deficient for both kinin receptor genes and leptin (obB1B2KO). Six-month-old obB1B2KO mice showed increased blood glucose levels. Isolated islets of the transgenic animals were more responsive to glucose stimulation releasing greater amounts of insulin, mainly in 3-month-old mice, which was corroborated by elevated serum C-peptide concentrations. Furthermore, they presented hepatomegaly, pronounced steatosis, and increased levels of circulating transaminases. This mouse also demonstrated exacerbated gluconeogenesis during the pyruvate challenge test. The hepatic abnormalities were accompanied by changes in the gene expression of factors linked to glucose and lipid metabolisms in the liver. Thus, we conclude that kinin receptors are important for modulation of insulin secretion and for the preservation of normal glucose levels and hepatic functions in obese mice, suggesting a protective role of the KKS regarding complications associated with obesity and T2DM
Avaliação do lodo de esgoto como alternativa para adubação orgânica em grama-esmeralda (<i>Zoysia japonica</i> Steud.)
O lixo e o lodo de esgoto (LE) são os principais resíduos produzidos nas cidades, são ricos em material orgânico e nutrientes, sugerindo aplicação no solo. No LE encontram-se nutrientes e metais pesados. O LE na agricultura vem sendo mundialmente pesquisado.
Dessa forma implantou-se um experimento em Manaus-AM para avaliar o LE como alternativa para adubação orgânica em grama-esmeralda (Z. japonica Steud.). Usou-se o Delineamento Inteiramente Casualizado, com 5 tratamentos e 5 repetições, sendo os tratamentos doses de LE: zero, 10, 20, 30 e 40 t/ha-1, respectivamente, T1, T2, T3, T4 e T5.
Foram avaliados os pesos da matéria seca (MS) da parte aérea e MS da raiz e cobertura do solo. A MS da parte aérea foi maior de forma gradativa, da menor dosagem para a maior dosagem, em todos os tratamentos. A cobertura da superfície do solo, visualmente, foi maior quanto maior foi à dose de LE, o maior percentual da biomassa da raiz em relação à biomassa total foi no T1 – Testemunha, com 41 %.Garbage and sewage sludge (SS) are the main waste produced in cities are rich in organic matter and nutrients, suggesting soil application. In SS are nutrients and heavy metals. The SS in agriculture has been researched worldwide. Thus we implemented an experiment in Manaus-AM to assess the SS as an alternative to organic fertilization on grass emerald (Z. japonica Steud.). It used the completely randomized design, with five treatments and five repetitions, and the SS doses treatments: zero, 10, 20, 30 and 40 t/ha-1, respectively, T1, T2, T3, T4 and T5. The weight of dry matter (DM) of shoot and root DM and land cover were evaluated. The DM of was higher gradually, the lowest dosage to the highest dosage, in all treatments. The coverage of the soil surface, visually, was greater the greater was the LE dose, the greatest percentage of root biomass to the total biomass was at T1 - Control with 41%.Eje A4: Ambiente, Naturaleza y AgroecologíaFacultad de Ciencias Agrarias y Forestale
Avaliação do lodo de esgoto como alternativa para adubação orgânica em grama-esmeralda (<i>Zoysia japonica</i> Steud.)
O lixo e o lodo de esgoto (LE) são os principais resíduos produzidos nas cidades, são ricos em material orgânico e nutrientes, sugerindo aplicação no solo. No LE encontram-se nutrientes e metais pesados. O LE na agricultura vem sendo mundialmente pesquisado.
Dessa forma implantou-se um experimento em Manaus-AM para avaliar o LE como alternativa para adubação orgânica em grama-esmeralda (Z. japonica Steud.). Usou-se o Delineamento Inteiramente Casualizado, com 5 tratamentos e 5 repetições, sendo os tratamentos doses de LE: zero, 10, 20, 30 e 40 t/ha-1, respectivamente, T1, T2, T3, T4 e T5.
Foram avaliados os pesos da matéria seca (MS) da parte aérea e MS da raiz e cobertura do solo. A MS da parte aérea foi maior de forma gradativa, da menor dosagem para a maior dosagem, em todos os tratamentos. A cobertura da superfície do solo, visualmente, foi maior quanto maior foi à dose de LE, o maior percentual da biomassa da raiz em relação à biomassa total foi no T1 – Testemunha, com 41 %.Garbage and sewage sludge (SS) are the main waste produced in cities are rich in organic matter and nutrients, suggesting soil application. In SS are nutrients and heavy metals. The SS in agriculture has been researched worldwide. Thus we implemented an experiment in Manaus-AM to assess the SS as an alternative to organic fertilization on grass emerald (Z. japonica Steud.). It used the completely randomized design, with five treatments and five repetitions, and the SS doses treatments: zero, 10, 20, 30 and 40 t/ha-1, respectively, T1, T2, T3, T4 and T5. The weight of dry matter (DM) of shoot and root DM and land cover were evaluated. The DM of was higher gradually, the lowest dosage to the highest dosage, in all treatments. The coverage of the soil surface, visually, was greater the greater was the LE dose, the greatest percentage of root biomass to the total biomass was at T1 - Control with 41%.Eje A4: Ambiente, Naturaleza y AgroecologíaFacultad de Ciencias Agrarias y Forestale
Avaliação do lodo de esgoto como alternativa para adubação orgânica em grama-esmeralda (<i>Zoysia japonica</i> Steud.)
O lixo e o lodo de esgoto (LE) são os principais resíduos produzidos nas cidades, são ricos em material orgânico e nutrientes, sugerindo aplicação no solo. No LE encontram-se nutrientes e metais pesados. O LE na agricultura vem sendo mundialmente pesquisado.
Dessa forma implantou-se um experimento em Manaus-AM para avaliar o LE como alternativa para adubação orgânica em grama-esmeralda (Z. japonica Steud.). Usou-se o Delineamento Inteiramente Casualizado, com 5 tratamentos e 5 repetições, sendo os tratamentos doses de LE: zero, 10, 20, 30 e 40 t/ha-1, respectivamente, T1, T2, T3, T4 e T5.
Foram avaliados os pesos da matéria seca (MS) da parte aérea e MS da raiz e cobertura do solo. A MS da parte aérea foi maior de forma gradativa, da menor dosagem para a maior dosagem, em todos os tratamentos. A cobertura da superfície do solo, visualmente, foi maior quanto maior foi à dose de LE, o maior percentual da biomassa da raiz em relação à biomassa total foi no T1 – Testemunha, com 41 %.Garbage and sewage sludge (SS) are the main waste produced in cities are rich in organic matter and nutrients, suggesting soil application. In SS are nutrients and heavy metals. The SS in agriculture has been researched worldwide. Thus we implemented an experiment in Manaus-AM to assess the SS as an alternative to organic fertilization on grass emerald (Z. japonica Steud.). It used the completely randomized design, with five treatments and five repetitions, and the SS doses treatments: zero, 10, 20, 30 and 40 t/ha-1, respectively, T1, T2, T3, T4 and T5. The weight of dry matter (DM) of shoot and root DM and land cover were evaluated. The DM of was higher gradually, the lowest dosage to the highest dosage, in all treatments. The coverage of the soil surface, visually, was greater the greater was the LE dose, the greatest percentage of root biomass to the total biomass was at T1 - Control with 41%.Eje A4: Ambiente, Naturaleza y AgroecologíaFacultad de Ciencias Agrarias y Forestale
Laurus nobilis (laurel) aqueous leaf extract's toxicological and anti-tumor activities in HPV16-transgenic mice
Cancers induced by human papillomavirus (HPV) infection remain a significant public health threat,
fueling the study of new therapies. Laurel (Laurus nobilis) compounds and extracts recently showed
in vitro activity against HPV-transformed cell lines. This work aims to evaluate the in vivo efficacy and
hepatic toxicity of a laurel extract in a transgenic mouse model of HPV16-induced cancer. The extract was
administered in drinking water (20 mg per animal per day) for three consecutive weeks, using four experimental
groups (n = 10) (group I: HPV16−/− without treatment, group II: treated HPV16−/−, group III: HPV16+/−
without treatment and group IV: treated HPV16+/−). Following the treatment period, animals were sacrificed
and skin samples were used to classify skin lesions histologically. Toxicological parameters included hematological
and biochemical blood markers, splenic and hepatic histology and hepatic oxidative stress. The
extract did not prevent the progression of HPV16-induced cutaneous lesions in this model. The treated wildtype
animals showed mild hepatitis, while transgenic animals suffered weight loss. However, there were no
changes concerning hematological, biochemical and hepatic oxidative stress markers.This work was supported by: Integrative Research in
Environment, Agro-Chains and Technology no. NORTE-01-
0145-FEDER-000017, in its line of research entitled ISAC, cofinanced
by the European Regional Development Fund (ERDF)
through NORTE 2020 (North Regional Operational Program
2014/2020). European Investment Funds by FEDER/COMPETE/
POCI– Operational Competitiveness and Internationalization
Programme, under Project POCI-01-0145-FEDER-006958 and
National Funds by FCT - Portuguese Foundation for Science
and Technology, under the project UID/AGR/04033/2013. This
study was also funded by Liga Portuguesa Contra o Cancro, by
the Research Center of the Portuguese Institute of Oncology of
Porto (CI-IPOP 37-2016), by project POCI-01-0145-
FEDER-006939 (Laboratory for Process Engineering,
Environment, Biotechnology and Energy – LEPABE), project
POCI-01-0145-FEDER-006958 and UID/AGR/04033/2013,
funded by FEDER funds through COMPETE2020 - Programa
Operacional Competitividade e Internacionalização (POCI) –
and by national funds through FCT – Fundação para a Ciência
e a Tecnologia; Rui M. Gil da Costa was funded by grant
number SFRH/BPD/85462/2012 from FCT, funded by the
Portuguese Government and the Social European Fund. The
authors are also grateful to FCT, Portugal and FEDER under
Programme PT2020 for financial support to CIMO (UID/AGR/
00690/2013), and to the Interreg España-Portugal for financial
support through the project 0377_Iberphenol_6_E.info:eu-repo/semantics/publishedVersio
Produção da cenoura e efeito na fertilidade do solo e nutrição decorrente da solarização do solo para controle da tiririca.
Dentre os desafios do cultivo orgânico de hortaliças destaca-se o controle de plantas daninhas, devido à proibição do uso de herbicidas. Entre as invasoras, a tiririca (Cyperus rotundus L.) é de difícil controle pela sua alta competitividade. A solarização é uma alternativa para desinfestação do solo, a qual consiste em cobri-lo com plástico transparente, com bons resultados no controle da tiririca. A fim de avaliar a influência do preparo e do revolvimento do solo sobre a eficiência da solarização no controle da tiririca, bem como seu posterior efeito sobre o cultivo da cenoura, foi realizado um experimento na Fazendinha Agroecológica, em Seropédica (RJ). O experimento foi disposto em blocos ao acaso com três repetições, em arranjo fatorial 2 x 3 mais uma testemunha adicional, sendo: 1) solo solarizado, preparado (com grade aradora) e revolvido 30 dias após a solarização (manualmente com auxílio de uma enxada); 2) solo solarizado, preparado e revolvido aos 60 dias; 3) solo solarizado, preparado e não revolvido; 4) solo solarizado, não preparado e revolvido aos 30 dias; 5) solo solarizado, não preparado e revolvido aos 60 dias; 6) solo solarizado, não preparado e não revolvido; solo não solarizado, não preparado e não revolvido (testemunha). A solarização iniciou-se em 29/1/2002, e durou cem dias. A solarização reduziu em 86% a infestação de tiririca no cultivo da cenoura. Até 10 cm de profundidade, a temperatura do solo foi superior nas parcelas solarizadas, porém a 5 cm, a solarização foi mais eficiente quando associada ao preparo do solo, não havendo efeito do revolvimento. A solarização aumentou os valores da biomassa microbiana e dos teores de Ca, Mg e P do solo. O desenvolvimento da cenoura foi influenciado pela solarização que resultou em maior produtividade
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