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A visible-light-driven, photocatalyst-free route starting from easily accessed ortho-hydroxycinnamic esters and O-perfluoropyridin-4-yl oximes has been successfully developed to rapidly assemble a wide range of 3-cyanoalkyl coumarins. This process does not require addition of external photocatalysts, exhibiting beneficial features including mild reaction conditions, synthetic simplicity, and excellent substrate compatibility. Extensive mechanistic investigations revealed that the in situ generated phenolate anions served as photosensitizers to drive this photoinduced transformation.
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As a probiotic, enterococcus faecium (E. faecium) has the characteristics of high temperature resistance, gastric acid resistance, bile salt resistance, etc. It can also effectively improve animal performance and immunity and improve the animal's intestinal environment, so in recent years it has been more widely used in the livestock industry. However, due to the improper use of antibiotics and the growing environmental stress of strains, the drug resistance of enterococcus faecium has become more and more serious, and because some enterococcus faecium carry virulence genes, leading to the emergence of pathogenic strains, its safety issues have been widely concerned. This paper focuses on the biological characteristics of enterococcus faecium, the application of this bacterium in animal husbandry and the safety issues in its use, with a view to providing a reference for the application of enterococcus faecium in the development of animal husbandry.
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Enterococcus faecium , Animais , Enterococcus faecium/genética , Criação de Animais Domésticos , Antibacterianos/farmacologia , Ácidos e Sais Biliares , GadoRESUMO
Direct oxidation of organosilanes is one of the most straightforward ways to access silanols. Herein, we describe a novel photo-induced strategy for oxidation of organosilanes to access silanols, promoted by a photoactive charge-transfer complex (CTC) between sodium benzenesulfinate and molecular O2. A streamlined sequence transformation of organosilanes to silyl ethers was also readily achieved. This developed protocol represents the first example of CTC-based oxidation of organosilanes, offering a facile approach to access a series of silanol and silyl ether products.
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With the Quanfuzhuang River basin located at Hani Rice Terrace core region as study area, we analyzed the isotopic composition and the effects of 12 surface water sampling sites for the forest landscape type and terrace landscape type from May 2015 to April 2016. The results showed that: 1) For the variation of isotope composition, both the average value and the variation range of δ18O in surface water under forest patches were smaller than that under terrace patches. 2) The overall elevation effect of the hydrogen and oxygen stable isotopes in surface water was obvious, except that in August and March, which could be expressed as the linear regression equation δ18O=-0.012H+13.84 (r=-0.83, n=12). 3) The altitude gradient of δ18O in surface water was -1.2·(100 m)-1, which was not the true altitude gradient affected by precipitation but by landscape gradient of δ18O in surface water between forest patches and terrace patches. 4) Under the "Forest-Terrace" landscape pattern, the δ18O differences in surface water between forest patches and terrace patches enhanced the elevation effect. Therefore, when landscape heterogeneity was strong, isotopic effect was strengthened, even with opposite isotope effect.
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Oryza , Água , Hidrogênio , Isótopos de Oxigênio/análise , RiosRESUMO
A highly modular 1,4-difunctionalization of 1,3-dienes with bromodifluoroacetamides and sulfinates/amines through a photoinduced palladium-catalyzed radical relay process is described herein. This developed protocol offers a facile and general route to access a variety of value-added CF2-incorporated alkenes in moderate to good yields. The versatility and flexibility of this approach have been well illustrated by readily accessible starting materials, synthetic convenience, and wide functional group compatibility.
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A novel visible-light-driven organocatalytic protocol to access aerobic oxidative cleavage of olefins, promoted by sodium benzene sulfinate, is described herein. An array of alkenes smoothly delivered the corresponding aldehydes and ketones under transition-metal-free conditions. Notably, α-halo-substituted styrenes proceeded with photoinduced oxidation to finally afford α-halo-acetophenones with halogen migration. Crucial to this oxidation was the formation of charge-transfer complexes between sodium benzene sulfinate with molecular O2 to ultimately deliver the carbonyl products.
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Herein, a tunable iodization/deuterolysis protocol for phosphonium ylides by employing D2O as the deuterium source was designed. Notably, this process could be manipulated by tuning the base, thus leading to two valuable deuterated building blocks - benzyl iodides and aromatic aldehydes with broad substrate scope, good functional group compatibility and excellent deuteration degree. Concise syntheses of a series of deuterated drug analogues have been achieved based on the developed deuteration reaction platform.
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Aldeídos , Iodetos , DeutérioRESUMO
Although the pollution of freshwater systems by microplastics and the resulting ecological effects have attracted widespread attention from scholars at home and abroad, the fragmentation of different types of microplastics in the natural environment has not yet received enough attention. To analyze the fragmentation processes and products of different types of microplastics, a 40 d natural light fragmentation experiment was carried out using four microplastics commonly found in water:polystyrene (PS), low-density polyethylene (LDPE), polypropylene (PP), and polyhydroxybutyrate (PHB). The pH, ORP, EC, and DO of the four types of plastic-aging liquids changed significantly during the aging process. During the weathering process, cracks and pores formed on the surface of LDPE and were later identified through scanning electron microscopy. Fourier transform infrared spectrometry indicated that the carbonyl index of LDPE increased the most in the experiment (an increase of 31.48%), suggesting that PP experienced significant aging. Dissolved organic carbon (DOC), a product of microplastics fragmentation, increased as weathering time progressed, and the concentration of DOC increased significantly after weathering for about 40 d. Compared with the baseline value, the concentration of DOC from PHB, PP, and LDPE in the leaching solution increased significantly, by 61.29%, 69.49%, and 89.15%, respectively. These results suggest that evident aging of microplastics in natural aquatic environments releases significant amounts of dissolved organic matter, and the ecological effects of this should be the subject of future research.
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Plásticos , Poluentes Químicos da Água , Carbono , Água Doce , Microplásticos , Poluentes Químicos da Água/análiseRESUMO
BACKGROUND: Acanthosis nigricans (AN), Leser-Trélat sign, and tripe palm are all skin diseases. To date, reports of these appearing as a paraneoplastic syndrome in a gastric cancer patient are quite rare. CASE SUMMARY: We report the case of a 61-year-old man with darkened skin color in the face and torso with no obvious inducement after 1 year of treatment for Riehl's melanosis. He had 40 brown maculopapular eruptions on his face and the top of his head with obvious itching. Papillary wart-like hyperkeratosis with dark brown pigmentation was also observed on both sides of the areola. He had papilloma-like lesions on the face, around the orbit, and on the neck. His bilateral palms had small, smooth, papillary projections with millet-like appearance. Histopathological examination of the skin showed that the patient was suffering from AN, tripe palms, and Leser-Trélat sign. Gastroscopy showed the patient's cardia was affected, and pathological biopsy revealed that he had moderate-to-poorly differentiated adenocarcinoma. Computed tomography test results showed that his cardia wall had thickened. Based on these histological and skin characteristics, the patient was diagnosed with gastric cancer with AN, tripe palms, and Leser-Trélat sign. CONCLUSION: Researchers should follow up on patients with malignant AN, Leser-Trélat sign, and tripe palms.
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Analysis of hydrogen and oxygen stable isotopes is an effective method to track the water cycle in watershed. Impact of landscape pattern on the isotope effects of spring water is a new interdisciplinary topic between landscape ecology and isotope hydrology. Taking the Quanfuzhuang River basin located in the core area of UNESCO World Cultural Heritage of Honghe Hani Rice Terrace as the object, collecting the monthly samples of 78 points of spring water and 39 precipitation at altitude of 1500 m (terraces), 1700 m (terraces) and 1900 m (forest) from March 2015 to March 2016, we analyzed the hydrogen and oxygen stable isotopes of water samples under the different landscape types. The results indicated that the dominated landscape types were forests and rice terraces, being 66.6% and 22.1% of the whole landscape area respectively, and they had a spatial vertical pattern of forest located at the mountain top and rice terraces at the down-slope. The correlation analysis showed that the spring water not only came from the precipitation, but also from other water sources which had a more positive δ18O and δD values, the spring water in up-slope forests mainly came from precipitation, while that in down-slope rice terraces came from precipitation, ri-ver water, rice terrace water and under ground water. Therefore, the mixing effects of spring water δ18O and δD were more significant in rice terraces. The overall altitude effect of the hydrogen and oxygen stable isotopes in spring water was obvious. The linear decreasing rates of δ18O and δD values were -0.125·(100 m)-1and -0.688·(100 m)-1, respectively. The deuterium surplus value increased with the altitude because of the impacts of landscape pattern and the local cycle of water isotopes. In summary, the dominant landscape types had a significant impact on the hydrogen and oxygen isotopes of spring water, which could be used as response indicator to reveal the impacts of landscape pattern on hydrological process.
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Hidrogênio , Oryza , Isótopos de Oxigênio , Deutério , Monitoramento Ambiental , ÁguaRESUMO
This research study measures psychological attraction in relation to food brands by football players advertisements. This research is based on consumer behavior and examines the effect of product choicesand has been conducted in the context of China using primary data analysis techniques. For analysis, the data is generated on the basis of responses to specific questions related to the psychological attraction, food brand advertisement, consumer behavior, and product choice. To measure the data, the smart PLS software ran different results such as statistical ratio analysis, T-test analysis, regression analysis, generalized linear model, and that reliability test analysis. This study aimed to better understand the components of product attributes in the sporting environment in order to better understand what makes a product-athlete endorsement connection more effective. While it is usual for businesses to utilize athletes for advertising and marketing their products or services, only a limited number of studies have looked at the qualities of athletes and the roles these characteristics play in developing an effective advertisement relationship. Analysis of data findings shows that psychological attraction has a positive and significant impact on consumer behavior and product choice. On the other hand, food brand advertisement shows a positive but insignificant effect on product choice.(AU)
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Humanos , Masculino , Feminino , Atletas , Indústria Alimentícia , Alimentos , Controle da Publicidade de Produtos , Publicidade Direta ao Consumidor , Comportamento do Consumidor , Futebol , Psicologia do Esporte , Medicina Esportiva , ChinaRESUMO
OBJECTIVE: To establish a method for extracting psoralen from the seed of Psoralea corylifolia L. METHODS: Crushed seed of Psoralea corylifolia L. was soaked with 50% ethyl alcohol solution, and the leaching solution was filtrated and distilled to remove alcohol. A slurry of the sediment was obtained and dissolved in methyl alcohol (MeOH), followed by treatment with active carbon for decoloration and evaporation of MeOH, resulting in a lamellar crystal after the sediment was kept still overnight. MeOH was applied to dilute the sticky solution, and after filteration, a yellow crystal was obtained, recrystallization of which in MeOH yielded white needle-like crystals. Thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC) were employed to determine the purity of the resultant substance, and UV and H1-NMR applied to identify its chemical structure. RESULTS AND CONCLUSION: The resultant crystal is confirmed to be pure monomers of psoraren with a yield of 0.147% from the seed (m/m) by this simple extraction method.