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31.
32.
Herregods G Van Camp J Morel N Ghesquière B Gevaert K Vercruysse L Dierckx S Quanten E Smagghe G 《Journal of agricultural and food chemistry》2011,59(2):552-558
In this project we report on the angiotensin I-converting enzyme (ACE)-inhibitory activity of a bovine gelatin hydrolysate (Bh2) that was submitted to further hydrolysis by different enzymes. The thermolysin hydrolysate (Bh2t) showed the highest in vitro ACE inhibitory activity, and interestingly a marked in vivo blood pressure-lowering effect was demonstrated in spontaneously hypertensive rats (SHR). In contrast, Bh2 showed no effect in SHR, confirming the need for the extra thermolysin hydrolysis. Hence, an angiotensin I-evoked contractile response in isolated rat aortic rings was inhibited by Bh2t, but not by Bh2, suggesting ACE inhibition as the underlying antihypertensive mechanism for Bh2t. Using mass spectrometry, seven small peptides, AG, AGP, VGP, PY, QY, DY and IY or LY or HO-PY were identified in Bh2t. As these peptides showed ACE inhibitory activity and were more prominent in Bh2t than in Bh2, the current data provide evidence that these contribute to the antihypertensive effect of Bh2t. 相似文献
33.
Sandy Adriaenssens Jeroen Staelens Karen Wuyts An de Schrijver Shari Van Wittenberghe Tatiana Wuytack Fatemeh Kardel Kris Verheyen Roeland Samson Pascal Boeckx 《Water, air, and soil pollution》2011,219(1-4):43-57
This study assessed the foliar uptake of 15N-labelled nitrogen (N) originating from wet deposition along with leaf surface conditions, measured by wettability and water storage capacity. Foliar 15N uptake was measured on saplings of silver birch, European beech, pedunculate oak and Scots pine and the effect of nitrogen form (NH 4 + or NO 3 ? ), NH 4 + to NO 3 ? ratio and leaf phenology on this N uptake was assessed. Next to this, leaf wettability and water storage capacity were determined for each tree species and phenological stage, and the relationship with 15NH 4 + and 15NO 3 ? uptake was examined. Uptake rates were on average five times higher (p?<?0.05) for NH 4 + than for NO 3 ? and four times higher for deciduous species than for Scots pine. Developing leaves showed lower uptake than fully developed and senescent leaves, but this effect was tree species dependent. The applied NH 4 + to NO 3 ? ratio did only affect the amount of N uptake by senescent leaves. The negative correlation between measured leaf contact angles and foliar N uptake demonstrates that the observed effects of tree species and phenological stage are related to differences in leaf wettability and not to water storage capacity. 相似文献
34.
Naaf Tobias Feigs Jannis Till Huang Siyu Brunet Jörg Cousins Sara A. O. Decocq Guillaume De Frenne Pieter Diekmann Martin Govaert Sanne Hedwall Per-Ola Lenoir Jonathan Liira Jaan Meeussen Camille Plue Jan Vangansbeke Pieter Vanneste Thomas Verheyen Kris Holzhauer Stephanie I. J. Kramp Katja 《Landscape Ecology》2022,37(5):1365-1384
Landscape Ecology - Plant populations in agricultural landscapes are mostly fragmented and their functional connectivity often depends on seed and pollen dispersal by animals. However, little is... 相似文献
35.
In late 2018, the fall armyworm(FAW) Spodoptera frugiperda Smith(Lepidoptera: Noctuidae) made its arrival in China and its populations have since proliferated across most of eastern Asia. While S. frugiperda exhibits a considerable dispersal capacity and engages in long-distance migration, there's only scant information on the species' flight capability. Here, we empirically assessed S. frugiperda flight activity under varying climatic conditions using a flight mill. More specifically, under laboratory conditions, FAW exhibited superior flight performance at 20–25°C and 60–90% relative humidity(RH). When quantifying flight performance over five consecutive nights(i.e., 10 h/night), all flight parameters initially increased and then gradually dropped and FAW adults attained a total flight distance, duration and velocity equal to 63.73 km(48.42–94.12 km)(median, quartile range), 24.12 h(20.87–27.73 h) and 2.73 km h~(–1)(2.13–3.33 km h~(–1)), respectively. Our work constitutes a first comprehensive assessment of S. frugiperda flight performance and provides baseline information for future efforts to forecast spatiotemporal changes in its geographical distribution, movement patterns and invasion trajectories. Such can ultimately permit a timely and targeted deployment of area-wide pest management measures against this newly-invasive pest in China and across eastern Asia. 相似文献
36.
Adult nutrition affects reproduction and flight performance of the invasive fall armyworm,Spodoptera frugiperda in China
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Li-mei HE Shan JIANG Yu-chao CHEN Kris A.G. WYCKHUYS Shi-shuai GE Wei HE Xi-wu GAO Kong-ming WU 《农业科学学报》2021,20(3):715-726
Floral resources, such as carbohydrate-rich nectar or pollen, can bolster fitness and raise reproductive output of adult lepidopterans. Here, we used laboratory experiments to assess how those plant-derived foods impact adult fecundity, reproductive physiology and flight performance of an invasive strain of the fall armyworm, Spodoptera frugiperda(FAW; Lepidoptera: Noctuidae) in China. More specifically, supplementary feeding on bee pollen and honey enhanced FAW flight duration, testis size, ovarian development, longevity and adult fecundity. FAW adults attained the longest pre-oviposition(10.8 days) and oviposition period(6.8 days) and longevity(19.2 days) on 5% acacia honey. Upon access to 2.5% acacia honey and 2.5‰ pine pollen, S. frugiperda attained the highest mating rate(79.7%), fecundity(644.9 eggs/female) and egg hatching rate(82.3%). Feeding on honey further delayed decay of male testes, while ovarian development was enhanced when female moths were allowed access to 2.5% honey and 2.5‰ pine pollen. Upon feeding on 5% honey solution, S. frugiperda engaged in flight over the longest duration(9.5 h), distance(29.9 km) and speed(3.1 km h~(–1)). Honey had a comparatively greater effect on the above parameters than pollen. Our findings help decipher FAW invasion patterns and population dynamics, facilitate the development of nutritional attractants, and contribute to integrated pest management of this newly-invasive pest in eastern Asia. 相似文献
37.
Establishment of reference values of the caudal vena cava by fast‐ultrasonography through different views in healthy dogs
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38.
Gelatin-sucrose gels containing the same amount of flavor compounds present as either suspended droplets or homogenously distributed in the gel (dissolved) were eaten, and the in vivo flavor release was studied using atmospheric pressure chemical ionization-mass spectrometry. The maximum intensity of release was higher from all droplet-containing samples as compared with the dissolved sample (by a factor of 4-2500-fold). When the flavor was dispersed as a greater number of smaller droplets rather than one 1 microL droplet, the intensity of in vivo release was slightly lower. The release of 16 of the flavor compounds varied in their Log P (range 0.26-4.83) and vapor pressure (Log vapor pressure ranged from -1.09 to 1.99). The differences in release for flavors present as either droplets or dissolved in the gel matrix were strongly influenced by both of these factors. This suggested a different mechanism for flavor release from droplets as compared to the classical partition mechanism established for dissolved flavors. 相似文献
39.
Reddy V Nathues A Le Corre L Sierks H Li JY Gaskell R McCoy T Beck AW Schröder SE Pieters CM Becker KJ Buratti BJ Denevi B Blewett DT Christensen U Gaffey MJ Gutierrez-Marques P Hicks M Keller HU Maue T Mottola S McFadden LA McSween HY Mittlefehldt D O'Brien DP Raymond C Russell C 《Science (New York, N.Y.)》2012,336(6082):700-704
Multispectral images (0.44 to 0.98 μm) of asteroid (4) Vesta obtained by the Dawn Framing Cameras reveal global color variations that uncover and help understand the north-south hemispherical dichotomy. The signature of deep lithologies excavated during the formation of the Rheasilvia basin on the south pole has been preserved on the surface. Color variations (band depth, spectral slope, and eucrite-diogenite abundance) clearly correlate with distinct compositional units. Vesta displays the greatest variation of geometric albedo (0.10 to 0.67) of any asteroid yet observed. Four distinct color units are recognized that chronicle processes--including impact excavation, mass wasting, and space weathering--that shaped the asteroid's surface. Vesta's color and photometric diversity are indicative of its status as a preserved, differentiated protoplanet. 相似文献
40.