RESUMO
In-situ measurements of soil water content provide important constraints on local/global hydrology. We demonstrate that the attenuation of the underground flux of cosmic-ray electromagnetic (EM) particles can be used to monitor the variation of soil water content after rainfalls. We developed a detection system that preferably selects EM particles by considering the coincidence of distant plastic scintillators. The calibration test beneath the water pool revealed that the count rate decreased by 0.6-0.7% with a 1 cm increase in the water level. The field measurement performed in the horizontal tunnel showed that the count rate dropped according to 48-h precipitation, after correcting the effects originating from atmospheric and water vapour pressures. These characteristics were confirmed using dedicated Monte Carlo simulations. This new method is called cosmic electromagnetic particle (CEMP) radiography.
RESUMO
The unknown constituents of the interior of our home planet have provoked the human imagination and driven scientific exploration. We herein demonstrate that large neutrino detectors could be used in the near future to significantly improve our understanding of the Earth's inner chemical composition. Neutrinos, which are naturally produced in the atmosphere, traverse the Earth and undergo oscillations that depend on the Earth's electron density. The Earth's chemical composition can be determined by combining observations from large neutrino detectors with seismic measurements of the Earth's matter density. We present a method that will allow us to perform a measurement that can distinguish between composition models of the outer core. We show that the next-generation large-volume neutrino detectors can provide sufficient sensitivity to reject extreme cases of outer core composition. In the future, dedicated instruments could be capable of distinguishing between specific Earth composition models and thereby reshape our understanding of the inner Earth in previously unimagined ways.
RESUMO
O gênero Croton possui seiscentas espécies e é originário de regiões tropicais. Croton gnaphelil é conhecida no sul do Brasil como infalivina, sendo utilizada popularmente nos distúrbios hepáticos. A substância majoritária presente nas partes aéreas desta planta foi isolada e identificada através de métodos espectroscópicos, sendo identificada como um glicosídeo acilado, o canferol‑3‑O‑(6"‑O‑p‑cumaroil)‑β‑D‑glicopyranose, também chamado de tilirosídeo.
Croton genus comprises six hundred species being native in tropical forests. Croton gnaphalliis popularly known as "infalivina" in South of Brazil and it is traditionally used for hepatic disorders. The major compound from aerial parts of this plant was isolated and its structure elucidated through spectroscopic analysis. It was identified as an acylglycoside, kaempferol‑3‑O‑(6"‑O‑p‑coumaroyl)‑ β ‑D‑glucopyranoside, known as tiliroside.
RESUMO
As part of an experimental study, crystal-associated cholangiopathy was induced in 9 sheep by grazing pure pastures of Brachiaria decumbens in Brazil. One of these sheep showed characteristic lesions of photosensitization. The analysis of the B decumbens samples by acidic hydrolysis followed by TLC and infrared spectrum revealed diosgenin as the principal sapogenin present in the plant. In the rumen contents samples from the B decumbens-grazing group were identified by TLC, 1H and 13C NMR and EIMS as epismilagenin, episarsasapogenin, and a mixture of smilagenin and sarsasapogenin. In the bile samples from the B decumbens-grazing group, TLC analysis demonstrated 2 compounds similar to epismilagenin and episarsasapogenin. However, by this same method, those compounds were not observed in the rumen contents and bile from 2 sheep which served as control animals. The P chartarum spore counts remained very low during the experimental period.
Assuntos
Colangite/veterinária , Hepatopatias/veterinária , Transtornos de Fotossensibilidade/veterinária , Poaceae/química , Sapogeninas/isolamento & purificação , Doenças dos Ovinos/etiologia , Animais , Ascomicetos/crescimento & desenvolvimento , Bile/química , Brasil , Colangite/induzido quimicamente , Colangite/etiologia , Cromatografia em Camada Fina/veterinária , Contagem de Colônia Microbiana/veterinária , Diosgenina/química , Diosgenina/isolamento & purificação , Diosgenina/toxicidade , Histocitoquímica , Fígado/patologia , Hepatopatias/etiologia , Hepatopatias/patologia , Espectroscopia de Ressonância Magnética , Espectrometria de Massas/veterinária , Transtornos de Fotossensibilidade/induzido quimicamente , Transtornos de Fotossensibilidade/etiologia , Poaceae/microbiologia , Poaceae/toxicidade , Rúmen/química , Sapogeninas/química , Sapogeninas/toxicidade , Ovinos , Doenças dos Ovinos/microbiologia , Doenças dos Ovinos/patologia , Espectrofotometria Infravermelho/veterinária , Espirostanos/química , Espirostanos/isolamento & purificação , Espirostanos/toxicidade , Esporos Fúngicos/crescimento & desenvolvimentoRESUMO
Two saponins and a sapogenin were isolated from the leaves of Ilex brevicuspis. Their structures were established by means of spectroscopic methods as brevicuspisaponin 1 (3-O-alpha-L-arabinopyranosyl-20(S)-19 alpha,24-dihydroxyursolic acid), brevicuspisaponin 2 (3-O-alpha-L-arabinopyranosyl-20(S)-19 alpha,23,24-trihydroxyursolic acid) and 23-methylester of 20(S)-3 beta,19 alpha,24-trihydroxyurs-12-en-23,28-dioic acid.
Assuntos
Glicosídeos/isolamento & purificação , Árvores/química , Triterpenos/isolamento & purificação , Glicosídeos/química , Espectroscopia de Ressonância Magnética , Folhas de Planta/química , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Triterpenos/químicaRESUMO
The structure of matesaponin 5, a novel saponin isolated from the leaves of the Ilex paraguariensis, was established as ursolic acid-3-0-{beta-D-glucopyranosyl-(1->3)-[alpha-L-rhamnopyranosyl-(1->2)]-alpha-L- arabino pyranosyl}-(28->1)-beta-D-glucopyranosyl-(1->4)-beta-D-glucopyranosyl-(1 ->6)-beta-D-glucopyranosyl] ester.
Assuntos
Plantas Medicinais , Saponinas/química , Triterpenos , Configuração de Carboidratos , Sequência de Carboidratos , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Estrutura Molecular , Extratos Vegetais , Folhas de Planta , Saponinas/isolamento & purificação , América do Sul , Espectrometria de Massas de Bombardeamento Rápido de ÁtomosRESUMO
The leaves of Ilex paraguariensis have yielded three new saponins named matesaponins 2, 3, and 4 [1-3], which have been characterized by chemical and nmr methods as ursolic acid 3-O-[beta-D-glucopyranosyl-(1-->3)-[alpha-L-rhamnopyranosyl- (1-->2)]]-alpha-L-arabinopyranosyl]-(28-->1)-beta-D-glucopyranosyl ester, ursolic acid 3-O-[beta-D-glucopyranosyl-(1-->3)-alpha-L-arabinopyranosyl]-(28-- >1)- [beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl]ester, and ursolic acid 3-O-[beta-D-glucopyranosyl-(1-->3)-[alpha-L- rhamnopyranosyl-(1-->2)]]-alpha-L-arabinopyranosyl]-(28-->1)-[beta -D- glucopyranosyl-(1-->6)-beta-D-glucopyranosyl]ester, respectively.