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951.
Electrization of particles of powder materials is a widely spread phenomenon that makes a practical impact on the functional efficiency of equipment designed for producing a broad range of processed disperse products (dry milk, flour, grain, etc.). The results of electrization tests of powder skim milk particles are presented. A mathematical model of inner and outer transfer of electric charge for a single powder skim milk particle is suggested. The studies on a specialized laboratory unit have made it possible to obtain data on triboelectric charging of particles in different testing conditions. 相似文献
952.
Aderolu Ademola Zaid Sahu Narrotam Prasad Fawole Femi John Nwachi Oster Francis 《东北农业大学学报(英文版)》2017,24(3)
A 45-day experiment was carried out to evaluate the growth performance,digestive enzymes activity and biochemical response of Cirrhinus mrigala fed graded levels of oil.Three isonitrogenous purified diets(6%,8%and 10%of oil)were formulated.A total of 108 juveniles of Cirrhinus mrigala(5.95±0.25)g were equally distributed in triplicate groups in nine plastic tanks of 100 L capacity and fed under natural light cycle.Growth performance of the fish significantly reflected the effect of inclusion levels of oil tested but the diet with 8%lipid had the best significant growth performance[%weight gain,Feed Conversion Ratio(FCR)and Specific Growth Rate(SGR)],across different experimental groups.Levels of secretion of digestive enzymes in the fish fed different experimental diets resulted in significant values of(p0.05)amylase and lipase,while Aspartate transaminase(AST),Alanine transaminase(ALT),Lactate dehydrogenase(LDH)and Malate dehydrogenase(MDH)values in the muscle and liver decreased significantly(p0.05)as the levels of oil in the diet increased.However,serum biochemical parameters did not record any significant difference(p0.05)with the exception of the total lipid across diets.The study confirmed the inclusion effect of graded levels of oil in juvenile Mrigal diet,but the inclusion should not be more than 8%to avert growth depression. 相似文献
953.
Brian Krienke Richard B. Ferguson Michael Schlemmer Kyle Holland David Marx Kent Eskridge 《Precision Agriculture》2017,18(6):900-915
Ground-based active sensors have been used in the past with success in detecting nitrogen (N) variability within maize production systems. The use of unmanned aerial vehicles (UAVs) presents an opportunity to evaluate N variability with unique advantages compared to ground-based systems. The objectives of this study were to: determine if a UAV was a suitable platform for use with an active crop canopy sensor to monitor in-season N status of maize, if UAV’s were a suitable platform, is the UAV and active sensor platform a suitable substitute for current handheld methods, and is there a height effect that may be confounding measurements of N status over crop canopies? In a 2013 study comparing aerial and ground-based sensor platforms, there was no difference in the ability of aerial and ground-based active sensors to detect N rate effects on a maize crop canopy. In a 2014 study, an active sensor mounted on a UAV was able to detect differences in crop canopy N status similarly to a handheld active sensor. The UAV/active sensor system (AerialActive) platform used in this study detected N rate differences in crop canopy N status within a range of 0.5–1.5 m above a relatively uniform turfgrass canopy. The height effect for an active sensor above a crop canopy is sensor- and crop-specific, which needs to be taken into account when implementing such a system. Unmanned aerial vehicles equipped with active crop canopy sensors provide potential for automated data collection to quantify crop stress in addition to passive sensors currently in use. 相似文献
954.
955.
Plant-derived secondary metabolites still constitute important resources for currently prescribed drugs and for the discovery of active principles which are effective in new indication areas. Promising compounds are often exclusively found in wild medicinal plants and the classical plant-based pharmaceutical production approach has been hampered by low yields, lack of reproducibility and the high complexity of plant extracts (Rischer and Oksman-Caldentey, 2005). Influencing the accumulation of target compounds by breeding or genetic engineering is greatly impeded because in most cases the general biosynthetic routes are incompletely understood. 相似文献
956.
The growing set of fully-sequenced angiosperm genomes highlight the role of polyploidy in angiosperm evolution suggest that even the high level of importance we had already attributed to this mechanism was inadequate.…… 《分子植物育种》2007,5(2):151
The growing set of fully-sequenced angiosperm genomes highlight the role of polyploidy in angiosperm evolution, and suggest that even the high level of importance we had already attributed to this mechanism was inadequate. 相似文献
957.
Mai H. ElNaggar Ghada M. Abdelwahab Omnia Kutkat Mohamed GabAllah Mohamed A. Ali Mohamed E. A. El-Metwally Ahmed M. Sayed Usama Ramadan Abdelmohsen Ashraf T. Khalil 《Marine drugs》2022,20(3)
Several natural products recovered from a marine-derived Aspergillus niger were tested for their inhibitory activity against SARS CoV-2 in vitro. Aurasperone A (3) was found to inhibit SARS CoV-2 efficiently (IC50 = 12.25 µM) with comparable activity with the positive control remdesivir (IC50 = 10.11 µM). Aurasperone A exerted minimal cytotoxicity on Vero E6 cells (CC50 = 32.36 mM, SI = 2641.5) and it was found to be much safer than remdesivir (CC50 = 415.22 µM, SI = 41.07). To putatively highlight its molecular target, aurasperone A was subjected to molecular docking against several key-viral protein targets followed by a series of molecular dynamics-based in silico experiments that suggested Mpro to be its primary viral protein target. More potent anti-SARS CoV-2 Mpro inhibitors can be developed according to our findings presented in the present investigation. 相似文献
958.
K. R. Kelly B. H. Pypendop K. L. Christe 《Journal of veterinary pharmacology and therapeutics》2014,37(5):480-485
This study reports the pharmacokinetics of buprenorphine in conscious rhesus macaques (Macaca mulatta) after intravenous (i.v.) and intramuscular (i.m.) administration. Four healthy, opioid‐naïve, socially housed, adult male macaques were used. Buprenorphine (0.03 mg/kg) was administered intravenously as a bolus or intramuscularly on separate occasions. Blood samples were collected prior to, and up to 24 h, postadministration. Serum buprenorphine concentrations were analyzed with liquid chromatography–mass spectrometry. Noncompartmental pharmacokinetic analysis was performed with commercially available software. Mean residence time in the i.v. study as compared to the i.m. study was 177 (159–189) vs. 185 (174–214) min, respectively [median (range)]. In the i.v. study, concentration back‐extrapolated to time zero was found to be 33.0 (16.8–57.0) ng/mL [median (range)]. On the other hand, the maximum serum concentration found in the i.m. study was 11.8 (6.30–14.8) ng/mL [median (range)]. Rhesus macaques maintained concentrations >0.10 ng/mL for over 24 h in the i.v. study and over 12 h in the i.m. study. Bioavailability was found to be 68.1 (59.3–71.2)% [median (range)]. No significant adverse effects were observed in the monkeys at the 0.03 mg/kg dose of buprenorphine during either study. 相似文献
959.
960.
The effects of porcine somatotropin and dietary lysine on growth performance and carcass characteristics of finishing swine 总被引:1,自引:0,他引:1
R D Goodband J L Nelssen R H Hines D H Kropf R C Thaler B R Schricker G E Fitzner A J Lewis 《Journal of animal science》1990,68(10):3261-3276
Seventy-two finishing pigs (initial weight = 57.6 kg) were utilized to determine the effects of porcine somatotropin (pST) and dietary lysine level on growth performance and carcass characteristics. Pigs were injected daily with 4 mg pST in the extensor muscle of the neck and fed either a pelleted corn-sesame meal diet (.6% lysine, 17.8% CP) or diets containing .8, 1.0, 1.2 or 1.4% lysine provided by additions of L-lysine.HCl. All diets were formulated to contain at least twice the required amounts of other amino acids. Control pigs received a placebo injection and the .6%-lysine diet. Increasing levels of dietary lysine resulted in increased ADG and improved feed conversion (quadratic, P less than .01) for pST-treated pigs. The calculated daily lysine intake was 16.6, 13.6, 19.6, 25.1, 29.6 and 33.6 g for the control and pST-treated pigs fed .6, .8, 1.0, 1.2 and 1.4% lysine, respectively, over the entire experiment. Breakpoint analysis indicated that cumulative ADG and feed conversion were optimized at 1.19 and 1.22% lysine, respectively. Longissimus muscle area and trimmed ham and loin weights increased as dietary lysine was increased among pST-treated pigs (quadratic, P less than .01). Breakpoint analysis indicated that 1.11% lysine maximized longissimus muscle area, whereas trimmed ham and loin weights were maximized at .91 and .98% lysine, respectively. Adjusted backfat thickness was not affected by dietary lysine, but pST-treated pigs had less backfat (P less than .05) than control pigs did. Percentage moisture of the longissimus muscle increased (linear, P less than .05), as did percentage CP (quadratic, P less than .05), whereas fat content decreased (linear, P less than .05) as lysine level increased. Similar trends in composition were observed for muscles of the ham (semimembranosus, semitendinosus, and biceps femoris). Shear-force values from the longissimus and semimembranosus were lowest for control pigs, but they increased as dietary lysine level increased among pST-treated pigs. Sensory panel evaluations indicated that juiciness and tenderness decreased (linear, P less than .05) as dietary lysine level increased. Plasma urea concentrations decreased linearly (P less than .01) on d 28 as lysine level increased, whereas plasma lysine and insulin were increased (quadratic, P less than .01). Plasma glucose and free fatty acid concentrations on d 28 tended to increase (quadratic, P less than .10) with increasing dietary lysine level.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献