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A new acridone alkaloid, reticarcidone A (1), decorated with an oxygenated isopentenyl group between C-1 and C-2, was isolated from the leaves of Citrus reticulata Blanco, together with nine known acridone alkaloids (2–10) and fifteen flavones compounds (11–25). The structure of those compounds were confirmed by analysis of comprehensive 1D and 2D NMR, and MS data. Reticarcidone A (1) was the first pyrano[2,3-a]acridone isolated from the genus Citrus. Some of these compounds showed moderated cytotoxicity against the five human tumor cell lines MCF-7, SMMC-7721, HL-60, A549 and SW480. [ABSTRACT FROM AUTHOR]

Objective To compare and analyze the current situation of Medical Technology development in domestic and foreign famous medical schools. Methods By searching U.S. News & World Report Best Global Universities Rankings, Academic Rankings of World Universities (ARWU), and the websites of domestic and foreign medical schools and Ministry of Education of China, and interviewing the experts, this study summarized the differences of Medical Technology discipline in China and aboard in three aspects, i.e. major setting, enrollment conditions and academic degree granting, and disciplinary strength. Results·In the U.S. News discipline rankings for undergraduate education,"Radiology, Nuclear Medicine & Medical Imaging" was the only subject in the field of Medical Technology. As for the discipline rankings for graduate education, the subject category of"Medicine" included"Radiology", and the subject category of"Health"contained several subjects related with Medical Technology, including"Audiology" "Rehabilitation Counseling" "Speech-Language Pathology" "Occupational Therapy"and"Physical Therapy" . In the ARWU,"Medical Technology" discipline contained"Medical Laboratory Technology""Neuroimaging"and"Radiology, Nuclear Medicine & Medical Imaging" . At the stage of undergraduate education in China, Medical Technology-related majors included 13 majors in the category of"Medical Technology"and 3 majors in the category of"Clinical Medicine" . At the stage of graduate education in China, Medical Technology-related majors included 11 majors in the category of "Medicine"and 2 majors in the category of"Natural Science" . Taking Rehabilitation-related majors as examples of enrollment condition and academic degree granting, there were many master's and doctoral programs abroad, and the enrollment conditions were flexible. However, the Rehabilitation-related majors in China concentrated on the undergraduate education; the graduate education enrollment required relevant professional background. In the ARWU, the top five universities in"Medical Technology"in Chinese mainland ranked 76-200 globally. The indicators of publications in the journals of Q1 range and in the top journals as well as the honours of prominent prizes were relatively low. Conclusion·There is still a gap in the international rankings of Medical Technology discipline between domestic universities and the top universities abroad. The construction of world's first-class discipline of Medical Technology in China will be boosted by optimizing the major setting, adjusting the professional education system and academic degree granting, and strengthening the scientific research. [ABSTRACT FROM AUTHOR]

The dielectric constant of hydrate-bearing-sediments (HBS) is a significant parameter in the exploration and development of hydrate resources. From the drilling results' the HBS of the permafrost region in Qilian Mountain mainly belongs to consolidated rock type. So it is difficult to locate the hydrate reservoir and estimate resources accurately' Ground Penetrating Radar and dielectric well logging become an important option. In this paper' the dielectric constant test system of HBS was designed and established to test core samples from DK-8 well in the hydrate drilling area of Qilian Mountain. The results showed that the dielectric constant of sandstone samples was associated with the frequency of the external electric field' which means a general trend of dielectric constant decreases with frequency increasing. However' high dielectric constants showed in the low frequency' while dielectric constants showed the exponential relationship with the frequency. The experiment results of HBS was conformed to the law of dielectric constant in rocks. In the same rock sample' the dielectric constant of HBS was between that of water-saturated rock and dry rock. In the gas saturated circumstances' the polarised water with high dielectric constant was transformed into hydrate with low dielectric constant in the pores of the same rock' which led to the dielectric constant of HBS lower than that of water-saturated rock. However' the dielectric constant of hydrate was higher than that of air' so that the dielectric constant of HBS was higher than that of the same dry rock' which indicated that hydrate in rock increases the dielectric constant of rock. The HBS samples showed the dispersion characteristics in 10 ~ 40 MHz frequency. However, the dispersion characteristic weakens and the dielectric constant was almost unchanged when the frequency was above 50 MHz. [ABSTRACT FROM AUTHOR]

By adopting characteristic index data for the Western Pacific Subtropical High (WPSH) from the National Climate Center of China, U.S. National Centers for Environmental Prediction-National Center for Atmospheric Research (NCEP/NCAR) reanalysis data, and the National Oceanic and Atmospheric Administration (NOAA) sea surface temperature (SST) data, we studied the WPSH variability considering the background of climate warming by using a Gaussian filter, moving averages, correlation analysis, and synthetic analysis. Our results show that with climate warming over the past 60 years, significant changes in the WPSH include its enlarged area, strengthened intensity, westward extended ridge point and southward expanded southern boundary, as well as enhanced interannual fluctuations in all these indices. The western ridge point of the WPSH consistently varies with temperature changes in the Northern Hemisphere, but the location of the ridgeline varies independently. The intensity and area of the WPSH were both significantly increased in the late 1980s. Specifically, the western ridge point started to significantly extend westward in the early 1990s, and the associated interannual variability had a significant increase in the late 1990s; in addition, the ridgeline was swaying along the north-south-north direction, and the corresponding variability was also greatly enhanced in the late 1990s. With climate warming, the SST increase becomes more weakly correlated with the WPSH intensity enhancement but more strongly correlated with the westward extension of the ridge point in the equatorial central and eastern Pacific Ocean in winter, corresponding to an expanding WPSH in space. In the northern Pacific in winter, the SST decrease has a weaker correlation with the southerly location of the ridgeline but also a stronger correlation with the westward extension of the ridge point. In the tropical western Pacific in winter, the correlations of the SST decrease with the WPSH intensity enhancement, and the westward extension of the ridge point is strengthened. These observations can be explained by strengthened Hadley circulations, the dominant effects of the southward shift, and additional effects of the weakened ascending branch of the Walker circulation during warm climatological periods, which consequently lead to strengthened intensities, increased areas, and southward expansions of the WPSH in summer. [ABSTRACT FROM AUTHOR]

Abstract: The spread of antimicrobial resistance and global change in air temperature represent two major phenomena that are exerting a disastrous impact on natural and social issues but investigation of the interaction between these phenomena in an evolutionary context is limited. In this study, a statistical genetic approach was used to investigate the evolution of antimicrobial resistance in agricultural ecosystem and its association with local air temperature, precipitation, and UV radiation. We found no resistance to mancozeb, a nonspecific fungicide widely used in agriculture for more than half a century, in 215 Alternaria alternata isolates sampled from geographic locations along a climatic gradient and cropping system representing diverse ecotypes in China, consistent with low resistance risk in many nonspecific fungicides. Genetic variance accounts for ~35% of phenotypic variation, while genotype–environment interaction is negligible, suggesting that heritability plays a more important role in the evolution of resistance to mancozeb in plant pathogens than phenotypic plasticity. We also found that tolerance to mancozeb in agricultural ecosystem is under constraining selection and significantly associated with local air temperature, possibly resulting from a pleiotropic effect of resistance with thermal and other ecological adaptations. The implication of these results for fungicide and other antimicrobial management in the context of global warming is discussed. [ABSTRACT FROM AUTHOR]

Macrobrachium nipponense is a new aquaculture species with high market demand and is preferred as food by Asian consumers. However, its nutrient requirements and optimal dietary sources have not been fully evaluated. In the present study, we examined four common plant protein sources (soybean meal, cottonseed meal, rapeseed meal, and peanut meal) as partial replacement for 25% fishmeal protein in five isonitrogenous and isocaloric diets in M. nipponense for 8 weeks. The nutritional effects of the four plant protein sources were compared by means of growth performance, feed efficiency, histology, biochemical composition, oxidative stress, total hemocyte count, and in vitro digestion. Prawns fed the diets containing soybean (730.96 ± 33.50%) and cottonseed meals (672.32 ± 74.52%) had higher weight gain than those fed on rapeseed (503.71 ± 50.85%) and peanut (507.79 ± 52.10%) meal diets ( p < 0.05). Similarly, the feed conversion ratios of prawns fed on soybean (1.66 ± 0.12%) and cottonseed (1.88 ± 0.06%) meal diets were significantly lower than those fed on rapeseed (2.37 ± 0.10%) and peanut (2.77 ± 0.16%) ( p < 0.05) meal diets. No significant differences were found among groups in the hepatopancreas and intestinal histological characteristics, activities of antioxidant enzymes, and hemocyte number. The amino acid composition in diets and prawn muscles was comparable among groups. Soybean meal showed the highest in vitro digestibility. Taken together, soybean and cottonseed meals could be good candidates for partial fishmeal replacement in M. nipponense diets . [ABSTRACT FROM AUTHOR]