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41.
42.
A trapezoidal labyrinth weir is a general transverse hydro-structure typically placed across rivers that causes longitudinal sediment discontinuity and affects riparian ecological system. A sediment exclusion labyrinth (SEL) weir is a modification designed to increase sediment exclusion from upstream to downstream over or through it. Hydraulic model experiments were carried out in straight rectangular cross-sectional open channel (15 m in length and 0.82 m in width). Four different shapes of weirs were examined. type 1 was a general labyrinth weir, whereas types 2–4 were SEL weirs with an inclined bottom slope (type 2), open slots (type 3), and reversed-wedge type holes (type 4). Standard sand (Jumunjin, Korea, d 50 = 0.56 mm, σ g = 1.48, SG = 2.65) was uniformly supplied upstream using an in-house grooved drum, and sediment exclusion efficiency was calculated from the ratio of sediment amount to excluded sediment yield for each type of weir. Higher efficiencies were founded in all SEL weirs compared with the sediment exclusion efficiency of the type 1 weir. In particular, type 2 and type 4 weirs were easy to construct and their flow patterns and hydraulic performance were similar to those of type 1. Finally, their sediment exclusion efficiencies were higher under a normal water level (F r ≤ 0.2), whereas the type 3 weir was the pattern favorable for a high water level (F r > 0.2) because its discharge capacity was significantly higher. Sediment exclusion characteristics were analyzed in terms of flow rate based on the decomposition analysis of residual sediment particle size distribution. It is expected that the results from this study will be used to design SEL weirs as basic materials if more hydrodynamic parameters are studied and combined with field monitoring. 相似文献
43.
Keum-Soon Im Il-Hwan Kim Na-Hyun Kim Ha-Young Lim Jong-Hyuk Kim Jung-Hyang Sur 《Veterinary journal (London, England : 1997)》2013,195(3):366-372
BRCA1 is a high-penetrance breast cancer susceptibility gene and BRCA1-associated breast cancer has a high familial prevalence that is more common among certain populations of humans. A similar high prevalence also exists for canine mammary tumors (CMTs) and the objective of this study was to determine the breed-related differences in malignant CMTs. Comparative analyses of the expression of various prognostic factors for CMTs, including BRCA1, estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER-2) were conducted on 139 malignant CMT cases from five breeds with the highest prevalence of CMTs in Korea.Significant breed-related differences were observed in the expression of BRCA1 (P = 0.003), histological grade (P = 0.038), and extensive lymphatic invasion (P = 0.042). The Shih Tzu breed had the highest proportion of dogs with malignant CMT and strong overexpression of BRCA1. Cytoplasmic and membranous expression of BRCA1 was associated with the ER negative (P = 0.004), PR negative (P = 0.046), and triple negative (ER, PR, and HER-2 negative; P = 0.016) phenotype and the basal-like molecular subtype (P = 0.019) in Shih Tzu dogs. Since these features are similar to BRCA1-related human breast cancer, dogs with BRCA1-associated CMT, particularly Shih Tzu dogs, may serve as a suitable spontaneous model, although additional molecular studies are needed. 相似文献
44.
Da Kyoung Yong Han Yong Jeon Jae Jung Yoo Jung Nam Im Seung Goo Lee 《Fibers and Polymers》2013,14(12):2122-2127
The PAR fiber reinforced PBT composite was manufactured using the PAR/PBT island-in-a-sea fiber. The isothermal crystallization kinetics of the PAR/PBT composite and the neat PBT resin were investigated in the temperature range of 187–199 °C. To calculate the Avrami parameters for analyzing the crystallization behavior, crystallization peaks were measured and analyzed in terms of the crystallization temperature and the inclusion of the PAR fiber. The crystallization rate of the PBT is faster than that of the PAR/PBT composite from the analysis of their relative crystallinity. Consequently, it is considered that the PAR fiber interrupted the crystal nucleation and growth of the PBT matrix. It can be confirmed with the crystallization half time and the crystalline morphologies at the chosen isothermal temperatures. 相似文献
45.
Intramuscular fat (IMF) in cattle is an important component of traits that influence meat quality. We measured carcass characteristics and gene expression in Korean steers to clarify the molecular mechanism(s) underlying IMF deposition in LM tissue by determining the correlation between IMF content and gene expression abundance and by developing models to predict IMF content using gene expression abundance. The deposition of IMF is determined by a balance between fat deposition and fat removal in the LM. We measured mRNA abundance of lipid metabolic genes including lipogenesis [acetyl CoA carboxylase (ACC), fatty acid synthase (FASN)], fatty lipid uptake [lipoprotein lipase (LPL), fatty acid translocase (CD36), fatty acid transport protein 1 (FATP1)], fatty acid esterification [glycerol-3-phosphate acyltransferase 1 (GPAT1), acylglycerol phosphate acyltransferase 1 (AGPAT1), diacylglycerol acyltransferase 1 (DGAT1), DGAT2], lipolysis [adipose triglyceride lipase (ATGL), hormone-sensitive lipase (HSL), monoglyceride lipase (MGL)], and fatty acid oxidation [carnitine palmitoyl transferase 1B, very long-chain acyl-CoA dehydrogenase (VLCAD), medium-chain acyl-CoA dehydrogenase (MCAD)] in the LM. The mRNA abundance of the GPAT1 gene showed the greatest correlation (r = 0.74; P < 0.001) with IMF content among 9 fat deposition genes. The gene expression abundance of other fat deposition genes including ACC, FASN, LPL, CD36, FATP1, AGPAT1, DGAT1, and DGAT2 also exhibited significant positive correlations (P < 0.05) with IMF content in the LM. Conversely, ATGL mRNA abundance showed the greatest negative correlation (r = -0.68; P < 0.001) with IMF content in the LM among 6 fat removal genes. The expression of other fat removal genes including MGL, VLCAD, and MCAD showed significant negative correlations (P < 0.05) with IMF content. Our findings show that the combined effects of increases in lipogenesis, fatty acid uptake, fatty acid esterification, and of decreases in lipolysis and fatty acid oxidation contribute to increasing IMF deposition in Korean steers. The multiple regression analysis revealed that the mRNA abundance of the GPAT1 gene in the LM was the first major variable predicting IMF content (54%) among 15 lipid metabolic genes. The second was mRNA abundance of ATGL (11%). In conclusion, these results suggest that GPAT1 and ATGL genes could be used as genetic markers to predict IMF deposition in the LM. 相似文献
46.
Effects of dietary mixture of garlic (Allium sativum), coriander (Coriandrum sativum) and probiotics on immune responses and caecal counts in young laying hens
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J. S. Lee M. J. Kim S. H. Park S. B. Lee T. Wang U. S. Jung J. Im E. J. Kim K. W. Lee H. G. Lee 《Journal of animal physiology and animal nutrition》2017,101(5):e122-e132
This study was conducted to evaluate the effects of a combined mixture of phytogenic extracts (garlic and coriander) and probiotics on growth performance and immune responses in laying hens based on the results of in vitro studies to screen for immunomodulatory potency of each ingredient. Several parameters of immunomodulatory potency were estimated using lamina propria leucocytes (LPLs) isolated from rat intestinal mucosa tissue. Results show that the combined mixture enhanced LPLs proliferation, increased LPL‐mediated cytotoxicity against YAC‐1 tumour cells, and decreased lipopolysaccharide (LPS)‐induced cytokine production including tumour necrosis factor‐α (TNF‐α) and interferon‐γ (IFN‐γ) in LPLs. For in vivo study, laying hens (n = 50/each diet group) were fed with control diet, a diet containing antibiotics (0.01% per kg feed) or the combined mixture (0.02% per kg feed) for 21 days. The dietary combined mixture improved egg production (p < 0.05) but not growth performance and carcass traits. Interestingly, the patterns of suppressing plasma IFN‐γ productions during inflammation by LPS injection and decreasing caecal E. coli counts in the combined mixture group were comparable to those in the antibiotics group. Taken together, our results suggested that the 0.02% of combined mixture of phytogenic extracts and probiotics as ingredients has potential immunomodulatory effects in laying hens. 相似文献
47.
This study considers a carbon tax system as a policy tool for encouraging carbon sequestration through modification of management in existing forests and examines its welfare impacts and costs of the carbon sequestered. The simulated carbon tax leads to reduced harvest and increased carbon stock in the standing trees and understory biomass. Changes in the level of silvicultural investments vary by owner, depending on the nature of their initial inventory. In general investment under the tax is concentrated in regimes that establish faster growing plantations. Average rotation age increases, varying in extent across ownerships and site qualities. The carbon tax reduces both consumer and producer surpluses in regional timber markets. Producers are compensated by the carbon subsidies, except at low carbon tax levels. Not all rates of carbon tax will attract interest from private owners if participation is voluntary. Estimates of the marginal cost of sequestering carbon in western Oregon private forests are shown to be within the range of costs for projects considering afforestation alone in some eastern regions of the United States. 相似文献
48.
Barbara Glanemann Karen Humm Mariana Abreu Sophie Aspinall David Buckeridge Hope Carveth Hannah Darcy Jessica Florey Polly Frowde Isuru Gajanayake Kate Green Emma Holmes Alenka Hrovat Anne-Katherine Jasensky Bryn A Jones Vasiliki Lantzaki Eve JY Lo Kirsty MacDonald Kevin O'Brien Alejandro Suárez-Bonnet Nele Van den Steen Balazs Szladovits Annelies Willems Helen Wilson 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2023,37(1):126-132
49.
Cardiopulmonary and anesthetic effects of the combination of butorphanol,midazolam and alfaxalone in Beagle dogs
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Jeong‐Im Seo Suk‐Hee Han Ran Choi Janet Han Lyon Lee Changbaig Hyun 《Veterinary anaesthesia and analgesia》2015,42(3):304-308
ObjectiveTo evaluate the physiological variables, arterial blood gas values, induction of anesthesia quality, and recovery quality using the combination of butorphanol, midazolam and alfaxalone in dogs.AnimalsTen healthy adult Beagle dogs weighing 8.3 ± 3.1 kg.MethodsRectal temperature (T), pulse rate (PR), respiratory rate (fR), mean arterial pressure (MAP), and arterial blood gases were measured and recorded prior to intravenous (IV) administration of butorphanol, prior to administration of both midazolam and alfaxalone IV 10 minutes later, then every 5 minutes for 20 minutes. M-mode echocardiographic left ventricular (LV) indices were measured before and 5 minutes after administration of alfaxalone. Qualitative scores for induction of anesthesia and recovery were allocated, duration of anesthesia and recovery were calculated, and adverse events were recorded.ResultsScores for induction and recovery quality were excellent. No significant adverse events were observed. Mean ± SD time from induction to extubation and to standing (full recovery) was 29 ± 6 and 36 ± 8 minutes, respectively. There were statistically significant changes in PR, fR and MAP after drug administration. Transient hypercarbia developed after alfaxalone injection. The echocardiographic LV indices were reduced after alfaxalone injection, although those changes were not statistically significant.Conclusions and clinical relevanceThe combination of butorphanol, midazolam and alfaxalone provided excellent quality of induction of anesthesia and exerted minimal cardiopulmonary effects in healthy dogs. 相似文献
50.
Vitrification of immature bovine oocytes by the microdrop method 总被引:4,自引:0,他引:4
Kim DH Park HS Kim SW Hwang IS Yang BC Im GS Chung HJ Seong HW Moon SJ Yang BS 《The Journal of reproduction and development》2007,53(4):843-851
This study was conducted to determine the optimal vitrification conditions for immature bovine oocytes using the microdrop method. In experiment 1, the optimal pre-equilibration period for microdrop vitrification was examined. The maturation rate of vitrified oocytes with a 3 min first pre-equilibration period (41.1%) was higher than that of vitrified oocytes with a 0 min first pre-equilibration period (21.4%), and the values of those with a 1 (33.9%) or 5 min (27.4%) first pre-equilibration period were intermediate. The value for a 1 min second pre-equilibration period (44.4%) was significantly higher (P<0.05) than those for a 0.5 (28.6%) and 2 min (21.4%) second pre-equilibration period. In experiment 2, the distribution of microtubules in matured oocytes was investigated. There was no difference among the first pre-equilibration times in terms of the rates of normal spindles in vitrified oocytes. However, this value was significantly higher (P<0.05) in the 1 min group (52.8%) compared with the 0.5 (16.7%) and 2 min groups (12.3%). In experiment 3, we investigated the developmental capacity of immature bovine oocytes vitrified under optimal pre-equilibration conditions (3 min and 1 min for the first and second pre-equilibrations, respectively). Although the total fertilization rates were significantly lower (P<0.05) in the vitrified oocytes (65.6%) compared with the control oocytes (92.4%), there was no difference in the rate of normal fertilization (2PN) between the vitrified (78.6%) and control (82.0%) oocytes. Cleavage and blastocyst rates were significantly lower (P<0.05) in vitrified oocytes (55.7 and 2.3%) than in control oocytes (84.4 and 34.7%). Thus, these results indicated that immature bovine oocytes can survive after microdrop vitrification and subsequently can be cultured to mature oocytes capable of undergoing fertilization in vitro and developing into blastocysts. 相似文献