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THE EFFECT OF NOISE ON STEREOPSIS IN DIFFERENT SPATIAL FREQUENCY CHANNELS
空间频率通道中噪声对体视匹配的影响

,郑竺英,贵昌
生物物理学报 , 1991,
Abstract: We attempted to understand the effect of noise on stereopsis in different spatial channels. Seven random noise images with noise level from 5% to 35% in every 5% interval were designed. These noise images and random-dot stereogram were filtered digitally by Butterworth filter and Gabor function filter with Centre frequency and band width as Wilson's four spatial frequency channels. Filtered stereograms added to the different noise images were examined under a stereoscope to see if any depth could be perceived.We get the results as follows.1. Stereoscopic noise tolerance in high frequency channel is greater than that in low frequency channel.2. Slereoscopic noise tolerance of unfiltered stereograms is the greatest, that of stereogram filtered by Gabor function filter is greater than that of stereogram filtered by Butterworth filter.3. When noise exceeds 15%, low frequency noise restrains the match between low frequency stereograms, so does high frequency noise to the match between low frequency stereograms or high frequency stereograms. However, low frequency noise has no effect on match between high frequency stereograms.4. The maximum noise tolerance of unfiltered stereogram and all stereograms of spatial frequency channels do not exceed 25%.
梨黑星病抗性机理的研究进展
张海娥,,张新忠
华北农学报 , 2007, DOI: 10.7668/hbnxb.2007.S2.056
Abstract: 综述了梨黑星菌的分化类型、侵入机制、抗性遗传及抗性机理的研究进展。梨黑星菌在叶片中寄生的具体位置是果胶层。V.nashicola对抗性、易感和非寄主材料的初期侵染相似,当真菌侵入角质层之后,亚角质层菌丝在易感材料中的增长速率远远高于抗性和非寄主材料,并且在抗性和非寄主材料上出现死亡菌丝,这些都表明抗性是在真菌侵入角质层之后表达的。梨黑星病抗性等位基因和敏感性等位基因定位于不同的连锁基因组上,梨黑星病抗性基因与苹果黑星病抗性基因具有同源性。
早熟梨新品种‘世纪梨’
,赵永波,张新忠,,韩继成
园艺学报 , 2005,
Abstract: ‘世纪梨’是由河北省晋州市相丘梨园中选出的变异单株选育而成,果实近圆形或扁圆形,绿黄色;平均单果质量200g,最大350g;可溶性固形物含量14.16%,风味酸甜,品质上乘;7月下至8月上旬成熟,抗黑星病,丰产。
京白梨果实采后pg、糖苷酶和lox活性变化及其基因表达特性
魏建梅,齐秀东,张海娥,冉辛拓,
园艺学报 , 2012,
Abstract: 以京白梨为试材,测定贮藏期间果实多聚半乳糖醛酸酶(pg)、糖苷酶(β-gal、α-l-af)及脂氧合酶(lox)活性及其基因表达变化及对1-mcp和低温的响应。结果表明,果实软化呈慢(3d内)、快(3~9d)、慢(9d后)的变化趋势;pg、β-gal、α-l-af和lox活性及其基因表达量均随果实软化呈不同程度增加,且β-gal和lox的活性均在果实采收后3d内上升快,其基因的表达量亦迅速增加,由此认为β-gal和lox可能在果实软化早期起着更为重要的作用。经1-mcp处理和冷藏后,β-gal、α-l-af、lox和pg的活性及基因表达显著受抑,延缓了果实软化进程,且1-mcp对β-gal和lox的抑制作用最强烈,尤其在处理前期。在果实冷藏过程中pg和β-gal活性基本维持原有水平,其基因表达在贮藏前期受到抑制,lox活性和基因表达均维持在极低水平,说明lox对低温较其它酶敏感。因此认为,pg、β-gal、α-l-af和lox均不同程度地参与了京白梨果实的后熟软化,在早期软化阶段β-gal和lox可能起着更为重要的作用,1-mcp对β-gal和lox活性和基因表达具有更显著的调控作用,而低温可能主要是通过抑制lox活性和基因表达来抑制果实软化。
用物性分析仪检测鸭梨和京白梨果实采后质地的变化
高海生,贾艳茹,魏建梅,冉辛拓,
园艺学报 , 2012,
Abstract: 采用物性分析仪测定鸭梨(pyrusbretschneiderirehd.‘yali’)和京白梨(pyrusussuriensismaxin.‘jingbaili’)果实质地参数的变化,分析其质地构成和变化特性。结果表明:硬度、破裂力、弹性、咀嚼性、粘附性和内聚性参数可较好地评价梨果实质地构成和变化。鸭梨果实各质地参数值变化很小,硬度与破裂力极显著正相关,二者均与咀嚼性极显著正相关,其它参数间的相关性均未达到显著水平。京白梨果实各质地参数值变化较大,硬度与破裂力极显著正相关,二者均与粘附性呈极显著负相关,与弹性和咀嚼性显著正相关;咀嚼性与粘附性亦显著正相关。硬度、破裂力、弹性和咀嚼性是评价质地的主要参数,粘附性和内聚性则反映了质地的细微变化。
纳西族村民糖尿病患病、知晓、治疗及控制现状
杨海涛,,, 苏蓉, 孙承欢, 和建
中国公共卫生 , 2014, DOI: 10.11847/zgggws2014-30-06-42
Abstract:
云南玉龙县纳西族居民烟草暴露影响因素分析
李江嵘,,和建,,宋莹
中国公共卫生 , 2014, DOI: 10.11847/zgggws2014-30-11-05
Abstract: ?目的了解云南省玉龙县纳西族居民烟草暴露现状及其吸烟和被动吸烟的影响因素。方法在云南省玉龙县采用比例概率抽样方法抽取2653名≥18岁村民进行问卷调查。结果云南省玉龙县纳西族村民吸烟率、被动吸烟率和尼古丁中度及以上依赖程度分别为34.0%、33.5%和11.0%;男性吸烟率(69.5%)高于女性(2.0%),男性尼古丁依赖程度(22.3%)也高于女性(0.9%),差异均有统计学意义(P<0.01);纳西族村民以吸过滤嘴香烟为主(89.9%),其初次吸烟年龄主要集中在12~20岁(76.7%);仅有22.3%的吸烟者在过去12个月内尝试过戒烟;过去7d内不吸烟者的被动吸烟场所在公共场所、工作场所和家里的比例分别为80.8%、79.9%、88.1%,女性分别为81.6%、82.7%、90.0%,均高于男性的78.4%、71.5%、82.6%,差异有统计学意义(P<0.01);文化程度(OR=0.717,95%CI=0.538~0.957)是纳西族村民吸烟的保护因素;在公共场所暴露于被动吸烟的可能性高于非公共场所(OR=1.61,95%CI=1.18~2.20)。结论云南省玉龙县纳西族控烟政策的制定应重点关注低文化程度人群和降低公共场所的被动吸烟率。
梨树树形与梨木虱种群发生关系研究
路晓楠,刘奇志,,王洁雯,徐金涛
北方园艺 , 2015, DOI: 10.11937/bfyy.201504027
Abstract: 以河北省农林科学研究院昌黎分所梨园为例,2013年周年调查了纺锤形和Y字形黄冠梨的梨木虱发生动态,研究该2种树形与梨木虱发生时间及其数量的关系。结果表明在相同管理模式下,2种树形的梨木虱发生时间动态无显著差别,但纺锤形树体的梨木虱数量明显低于Y字形树体的数量,表明纺锤形树形可以减轻梨木虱的危害。
埋深与压力对微润灌湿润体水分运移的影响
,张俊,张琳琳,薛万来,
农业机械学报 , 2013, DOI: 10.6041/j.issn.1000-1298.2013.12.021
Abstract: 为探明微润灌土壤湿润体特性,设置5个不同埋深,6个不同压力水头,通过室内土箱试验研究了微润灌土壤水分运动规律。结果表明:压力水头是决定微润灌流量的重要因素;微润带埋深显著影响土壤湿润体的形状,湿润锋水平运移距离与宽深比γ均随埋深的增大而减小,垂直运移距离随埋深的增大而略微增大;土壤累计入渗量与埋深呈负相关关系;累计入渗量随灌水时间的变化过程符合Kostiakov入渗模型,建立了不同埋深累计入渗量预测模型,并用实测值进行了验证,实测值与预测值具有较高的相关性;土壤湿润均匀系数与埋深呈正相关,粘壤土微润灌最适埋深为15~20cm。
THE EFFECT OF CHANGING SIZE OF RDS ON THE PLASTICITY OF STEREOPSIS
立体图对的尺寸变化对立体感可塑性的影响

贵昌,周桂荣,郑竺英,程立海,,朱立新,赵宁
生物物理学报 , 1990,
Abstract: In order to study the effect of different spatial parameters of RDS on the plasticity of stereopsis, three sets of psychophysical experiments were conducted under the following stimulus conditions.The first one was changing the size of one of two-half pictures of RDS in both horizontal and vertical directions. The second was changing of the size in horizontal direction and the third was changing of the size in vertical direction.The results showed that when the size of one half-picture of RDS was changed in different directions, the limitations of plasticity of stereopsis (LPS) were significant. The LPS was the smallest in the first experiment, the LPS was the largest in the second experiment and the LPS is middle in the third experiment.For 3 sizes of RDS, the effect of their size on the LPS was not significant.
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