Amoebic gill disease: sequential pathology in cultured Atlantic salmon, Salmo salar L

Amoebic gill disease (AGD) affects the marine culture phase of Atlantic salmon, Salmo salar L., in Tasmania. Here, we describe histopathological observations of AGD from smolts, sampled weekly, following transfer to estuarine/marine sites. AGD was initially detected histologically at week 13 post-transfer while gross signs were not observed for a further week post-transfer. Significant increases (P < 0.001) in the proportion of affected gill filaments occurred at weeks 18 and 19 post-transfer coinciding with the cessation of a halocline and increased water temperature at the cage sites. The progression of AGD histopathology, during the sampling period, was characterized by three phases. (1) Primary attachment/interaction associated with extremely localized host cellular alterations, juxtaposed to amoebae, including epithelial desquamation and oedema. (2) Innate immune response activation and initial focal hyperplasia of undifferentiated epithelial cells. (3) Finally, lesion expansion, squamation-stratification of epithelia at lesion surfaces and variable recruitment of mucous cells to these regions. A pattern of preferential colonization of amoebae at lesion margins was apparent during stage 3 of disease development. Together, these data suggest that AGD progression was linked to retraction of the estuarine halocline and increases in water temperature. The host response to gill infection with Neoparamoeba sp. is characterized by a focal fortification strategy concurrent with a migration of immunoregulatory cells to lesion-affected regions.     

Analysis of Spectral Characteristics Based on Optical Remote Sensing and SAR Image Fusion

Because of cloudy and rainy weather in south China, optical remote sens-ing images often can＇t be obtained easily. With the regional trial results in Baoying, Jiangsu province, this paper explored the fusion model and effect of ENVISAT/SAR and HJ-1A satel ite multispectral remote sensing images. Based on the ARSIS strat-egy, using the wavelet transform and the Interaction between the Band Structure Model （IBSM）, the research progressed the ENVISAT satel ite SAR and the HJ-1A satel ite CCD images wavelet decomposition, and low/high frequency coefficient re-construction, and obtained the fusion images through the inverse wavelet transform. In the light of low and high-frequency images have different characteristics in differ-ent areas, different fusion rules which can enhance the integration process of self-adaptive were taken, with comparisons with the PCA transformation, IHS transfor-mation and other traditional methods by subjective and the corresponding quantita-tive evaluation. Furthermore, the research extracted the bands and NDVI values around the fusion with GPS samples, analyzed and explained the fusion effect. The results showed that the spectral distortion of wavelet fusion, IHS transform, PCA transform images was 0.101 6, 0.326 1 and 1.277 2, respectively and entropy was 14.701 5, 11.899 3 and 13.229 3, respectively, the wavelet fusion is the highest. The method of wavelet maintained good spectral capability, and visual effects while improved the spatial resolution, the information interpretation effect was much better than other two methods.     

基于岩心图像压缩的编辑器设计

岩心图像数据量很大,不便存储和传输,需要进行压缩。岩心图像编辑器采用标准的JPEG压缩方法,需要对编辑器进行设计。编辑器结构分为编码过程和解码过程,其功能包括FDCT(正向离散余弦变换)和IDCT(DCT逆变换)、量化和反量化、DC编解码和AC系数排序、熵编码和熵解码。可实现岩心图像的无损压缩。     

基于openCV的玉米株型骨架提取研究

作物株型形态参数,一直是作物栽培及育种中所关注的指标。以粮食作物玉米的株形图像为研究对象,基于Intel公司的开源计算机视觉库OpenCV,以Microsoft Visual Studio 2008为开发平台,综合运用图像处理与分析技术,提出了一种适应玉米株形骨架提取的简便算法,并开发了玉米株型骨架提取软件。实证检验表明,该软件能实现载入一张复杂背景的玉米株形图像,经过剪切、自适应窗口等前期处理及对原始彩色图像的灰度化处理、图像分割和噪声去除等一系列的预处理,最后采用基于C#版的OpenCV(EmguCV)的一个算法提取出玉米株形的简单骨架。     

Desiring image for Women in Modern Chinese Writers＇ ＂South Pacific＂ Story

研究了现代作家有关“南洋”女性人物的作品,认为中国现代作家笔下涉及“南洋”故事的女性描写,多呈现出“男权主义”的叙境。其中包括“景色女”的被凝视、“商人妇”的被“闺范”以及“英雄妻”附属性的被欲望化叙事,所有这一切都显示了“菲勒斯中心主义”的欲像图式的胜利。     

基于迁移学习的葡萄叶片病害识别及移动端应用

为解决已有的卷积神经网络在小样本葡萄病害叶片识别的问题中出现的收敛速度慢,易产生过拟合现象等问题,提出了一种葡萄叶片病害识别模型(Grape-VGG-16,GV),并针对该模型提出基于迁移学习的模型训练方式.将VGG-16网络在ImageNet图像数据集上学习的知识迁移到本模型中,并设计全新的全连接层.对收集到的葡萄叶...     

桃叶蓼白粉菌的显微观察及进化关系分析

研究旨在通过对桃叶蓼白粉病的显微观察和进化关系的分析来鉴定该病原菌的种类和寄主范围,为桃叶蓼白粉病的防治提供合理依据。以桃叶蓼上发生的白粉病菌为试材,采用显微观察法对桃叶蓼上的白粉菌分生孢子、子囊、子囊孢子等进行形态观察和描述;使用试剂盒法提取桃叶蓼白粉菌DNA并进行ITS扩增。经过显微观察发现,桃叶蓼白粉菌分生孢子呈柱形;子囊果呈暗褐色,多数聚生或者近聚生,多呈扁球形;子囊多数呈各种不规则卵形,其中多含2~4个椭圆形子囊孢子,结合与其他白粉菌进行碱基序列比对和亲缘关系分析,确定该菌种与GenBank中的Polygonum aviculare（登录号为LC328322.1）、Polygonum erectum（登录号为KX826856.1）之间的亲缘关系最为接近,碱基序列相似度值达到99%,初步判定桃叶蓼白粉病病原菌与这两种菌种为同种同属。     

基于QuickBird遥感影像的城市绿地调查及建设策略——以张家界市城区为例

以QuickBird卫星影像数据为基础数据源,结合RS、GIS技术,主要采用计算机监督分类结合目视解译获取城市绿地类型信息的方法,调查张家界市城区绿地状况,计算张家界市城区绿地的相关景观格局指数.基于景观生态学原理,对张家界市城市绿地建设提出扩大绿化面积、加快绿地建设,拓宽道路绿地、提高廊道效益,\"点、线、面\"一体化、完善绿地体系等建设策略.     

Evaluation Method of Solubility of Wheat Straw in LiCl/DMSO Solvent北大核心CSCD

In order to solve the quantitative problem of the solubility of lignocellulosic biomass in the solvent system, wheat straw was studied as raw material for a ball milling time on its dissolution behavior in the LiCl/DMSO system. The dissolution performance was evaluated by visual method, optical microscopy and turbidity method respectively. By comparison of visual colorimetry method and the optical microscopy method at the condition of wheat straw dissolved in 8% LiCl/DMSO, it was found that the turbidimetric method is accurate, simple and quantitative. The turbidimetric method can be used to evaluate the dissolution behavior of lignocellulosic biomass during pretreatment and refining. © 2018, Editorial Board of «Chemistry and Industry of Forest Products». All right reserved.