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391.
小波变换与分水岭算法融合的番茄冠层叶片图像分割 总被引:1,自引:0,他引:1
在基于机器视觉的作物营养诊断研究中,通常需要采集叶片样本并在实验室条件下定量测定其营养素含量,但由于叶片间相互重叠,往往使得叶片样本不能清晰地反映在群体番茄冠层图像中。为了解决这一问题,需要利用图像分析技术有效提取作物冠层图像中的叶片,并根据处理结果采集实验室测定样本。本文从复杂背景剔除、梯度图计算、小波变换、标记选取、分水岭分割等环节出发,实现了基于小波变换与分水岭算法融合的番茄冠层多光谱图像叶片分割。首先对比了4种复杂背景剔除算法,发现当增强因子a=1.3时,基于归一化植被指数(Normalized difference vegetation index,NDVI)的阈值分割目标提取准确,适合各种光照条件,时空复杂度低。其次在梯度图计算方面,近红外(Near infrared,NIR)波段图像形态学梯度在保持目标边缘的同时,能消除大量由叶脉、光照等引起的叶片内纹理细节。然后以小波分析为基础进行标记选取,发现当选取db4小波函数、4层小波分解低频系数、阈值为18的H-maxima变换能得到最优的目标标记结果。最后对多光谱番茄冠层图像的小波变换分水岭分割和数学形态学分水岭分割结果进行叠加,发现对复杂背景及不同光照强度下的番茄冠层叶片平均误分率为21%,为基于多光谱图像分析的番茄叶片营养素含量检测提供了一定的技术支持。 相似文献
392.
Chan Sol Kang Il Jae Lee Moo Song Seo Sun Hong Kim Doo Hyun Baik 《Fibers and Polymers》2017,18(8):1580-1585
We purified as-received CNT fibers (CNTFs) with four different methods and systematically examined effects of various purifications on the morphology, structure, and electrical conductivity of the resultant CNTFs, respectively. The purified CNTFs were characterized by an optical microscope, transmission electron microscope (TEM) coupled with an energy dispersive X-ray spectrometer (EDS), Raman spectroscopy, and multiple source meters. Optical images showed that morphology of CNTFs did not largely change after purification. TEM images and EDS results showed that the Fe impurities, 21.9 wt%, in CNTFs were decreased to 0.17-1.20 wt% and were nearly eliminated by acid and alkali purifications, respectively. Raman results identified the ID/IG ratio of CNTFs was 0.71, while those of HCl treatment after steam with heat (HSCNTFs-HCl), NaOCl treatment after steam with heat (HSCNTFs-NaOCl), and NaOH treatment with heat without steam (NaOH-HCNTFs) were 0.45, 0.49, and 0.57, respectively, which means that purification methods of CNTFs performed in this study are thought to be satisfactory for manufacturing high-purity CNTFs. Electrical conductivity (1.4×104 S/m) of NaOH-HCNTFs (one-step procedure) was twice as high as that (7.3×103 S/m) of CNTFs, but lower than those (2.1-2.3×104 S/m) of HSCNTFs-HCl and HSCNTFs-NaOCl (two-step processes), which demonstrates that two-step processes rather than one-step procedure would have a positive effect on the electrical conductivity of the resultant CNTFs. 相似文献
393.
394.
The effect of glycyrrhizin on rainbow trout, Oncorhynchus mykiss (Walbaum), leucocyte responses 总被引:1,自引:0,他引:1
S. I. JANG M. J. MARSDEN Y. G. KIM M. S. CHOI C. J. SECOMBES 《Journal of fish diseases》1995,18(4):307-315
Abstract. Treatment of rainbow trout macrophages with glycyrrhizin (GL), an aqueous extract of licorice, Glycyrrhiza glabra , enhanced their respiratory burst activity. Maximal effects were seen using concentrations of 10–100 μml−1 . GL also modulated trout lymphocytes, increasing proliferation responses to the mitogen phytohaemagglutinin some two-fold over a range of GL concentrations. In addition, GL elicited the release of a macrophage activating factor (MAF) from head kidney leucocytes, as assessed by the ability of generated supernatants to increase respiratory burst activity of target macrophages. MAF activity was most apparent using 100 μg ml−1 GL to induce MAF release and a 48-h incubation period with the target macrophages. Finally, GL was shown to enhance the release of MAF in response to the mitogen concanavalin A. The possible use of GL as a stimulant of fish innate defences is discussed. 相似文献
395.
Erika KAWASAKI Makoto HASEBE Ji-Hee HWANG Eun-Young KIM Kisup LEE Kunikazu MOMOSE Hiroki TERAOKA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(2):233
Red-crowned cranes Grus japonensis, which are an endangered species, have two separate populations, a mainland population in the Eurasian continent and an island population in eastern Hokkaido, Japan. Island cranes showed three haplotypes (Gj1, Gj2 and Gj13), whereas ten haplotypes (Gj3–Gj12) were confirmed in captive cranes and stray cranes. We found Gj5 haplotype in feathers of two cranes as well as four new haplotypes in seven wild crane feathers collected in South Korea. We also found feathers in the nest in Sarobetsu Wetland in northwestern Hokkaido. While the haplotype of female-derived feathers was Gj2, that of male-derived feathers was Gj5. The results suggest that there has been crossbreeding between cranes in the island population and cranes in the mainland population. 相似文献
396.
Jin-A LEE Bock-Gie JUNG Tae-Hoon KIM Yun-Mi KIM Hong-Bum KOH Bong-Joo LEE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(9):1087-1094
Biotite and bentonite are phyllosilicate minerals that were originally used in
industrial applications. Several beneficial activities of them have recently been
reported, especially regulation of the immune system and antimicrobial effects. Therefore,
we investigated the immune-enhancing and bacterial clearance effects of a biotite and
bentonite mixture (BBM) on experimental infection of Salmonella enterica
serovar Typhimurium (S. Typhimurium) to determine whether the BBM could
be used as an alternative antibiotic. We administered 1% or 2% BBM as a feed supplement.
We then evaluated the bacterial clearance effects of the BBM against S.
Typhimurium. We also evaluated the immune-enhancing effect of the BBM through several
immunological experiments that included examination of the lysozyme activity,
CD4+/CD8+ T lymphocyte ratio and the T-helper type 1 (Th 1)
cytokine profile. The clinical signs of S. Typhimurium and the number of
viable bacteria in feces and tissues were significantly decreased in both BBM groups,
especially in the 2% BBM group. The BBM also markedly enhanced the lysozyme activity,
CD4+/CD8+ T lymphocyte ratio and expression levels of IFN-γ and
IL-12 in S. Typhimurium-challenged pigs. Therefore, the BBM could be a
good candidate as an alternative antibiotic that improves Th 1-specific immune responses
and the bacterial clearance effect. 相似文献
397.
Growth and Body Composition Effects of Tuna Byproduct Meal Substituted for Fish Meal in the Diet of Juvenile Abalone,Haliotis discus 下载免费PDF全文
Won‐Gwan Jung Hee Sung Kim Ki Wook Lee Ye Eun Kim Dong Kyu Choi Bok‐Il Jang Sung Hwoan Cho Cheol Young Choi Byeng‐Hak Kim Yang‐Ick Joo 《Journal of the World Aquaculture Society》2016,47(1):74-81
The effects on growth and body composition that result from tuna byproduct meal (TBM) substituted for fish meal in the diet of juvenile abalone, Haliotis discus, were determined. One thousand two hundred sixty juvenile abalone were randomly distributed into 18 70‐L plastic rectangular containers. Six experimental diets were prepared in triplicate. The TBM0 diet included 28% fish meal and 13% soybean meal as the protein source. Twenty‐five, 50, 75, and 100% of the fish meal were substituted with TBM. Finally, salted sea tangle was prepared. The essential amino acids, such as isoleucine, lysine, and valine, tended to decrease with the dietary substitution of TBM for fish meal in the experimental diets. The weight gain and specific growth rate (SGR) of abalone that were fed the TBM25 diet were higher than those of abalone that were fed the other diets. The crude protein content of the soft body of the abalone linearly decreased with the dietary substitution of TBM for fish meal. In conclusion, as much as 75% of the fish meal in the diet of abalone can be replaced with TBM without retardation in weight gain and SGR of the abalone when 28% fish meal was included. 相似文献
398.
Sileshi BELEW Jin-Yoon KIM Md.Akil HOSSAIN Ji-Yong PARK Seung-Jin LEE Yong-Soo PARK Joo-Won SUH Jong-Choon KIM Seung-Chun PARK 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(3):327-329
Pharmacokinetic (PK) parameters of marbofloxacin (MRFX) in Korean cattle, Hanwoo, were
determined following its intravenous (i.v.) or intramuscular (i.m.) administration at a
dose of 2 mg/kg. Area under the curve (AUC0–24 hr), half-life (t1/2)
and total body clearance (CLB) of i.v. MRFX were 6.87
hr∙µg/ml, 2.44 hr and 0.29 l/kg∙hr,
respectively, and the corresponding values for i.m. administration of MRFX were 5.07
hr∙µg/ml, 2.44 hr and 0.39 l/kg∙hr.
The suggested optimal doses of MRFX in Hanwoo cattle, calculated by integration of PK data
obtained in the present study and previously reported minimum inhibitory concentration
(MIC) for MRFX against susceptible (MIC ≤1 µg/ml) and
intermediate (MIC ≤2 µg/ml) pathogenic bacteria, were
2.1 and 4.2 mg/kg/day by i.v. route and 3.9 and 7.8 mg/kg/day by i.m. route. 相似文献
399.
Qiao-Chu WANG Jun LIU Xing DUAN Xiang-Shun CUI Nam-Hyung KIM Bo XIONG Shao-Chen SUN 《The Journal of reproduction and development》2015,61(1):49-53
Dynamin 2 is a large GTPase notably involved in clathrin-mediated endocytosis, cell migration and cytokinesis in mitosis. Our previous study identified that Dynamin 2 regulated polar body extrusion in mammalian oocytes, but its roles in early embryo development, remain elusive. Here, we report the critical roles of Dynamin 2 in mouse early embryo development. Dynamin 2 accumulated at the periphery of the blastomere during embryonic development. When Dynamin 2 activity was inhibited by Dynasore, embryos failed to cleave to the 2-cell or 4-cell stage. Moreover, the actin filament distribution and relative amount were aberrant in the treatment group. Similar results were observed when embryos were cultured with Dynasore at the 8-cell stage; the embryos failed to undergo compaction and develop to the morula stage, indicating a role of Dynamin 2 in embryo cytokinesis. Therefore, our data indicate that Dynamin 2 might participate in the early embryonic development through an
actin-based cytokinesis. 相似文献
400.
研究了核桃楸树皮丙酮-水提取物的水溶性萃取部位的化学成分。采用Sephadex LH-20柱色谱及薄层色谱等方法进行分离,经波谱分析及理化性质测定,鉴定了6个化合物:没食子酸(1)、鞣花酸(2)、1,2,6-三没食子酰葡萄糖(3)、1,3,6-三没食子酰葡萄糖(4)、1,2,4,6-四没食子酰葡萄糖(5)及1,2,3,4,6-五没食子酰葡萄糖(6)。化合物2、4、6为首次从该植物中分得。 相似文献