基于主成分与聚类分析的樱桃番茄品质综合评价

为探讨育种材料之间的品质差异,筛选适宜的推广品种,对29份樱桃番茄杂交组合的14个品质相关指标进行测量,运用描述性分析、主成分分析、聚类分析和判别分析对樱桃番茄进行综合评价。结果表明,番茄红素的变异系数最大,达到59%;横径的变异系数最小,仅为11%。主成分分析将14个品质指标简化为5个因子,累积贡献率达79.05%。结合聚类分析,筛选出决定番茄综合品质的6个指标——单果重、糖酸比、硬度、果形指数、V_C和番茄红素。综合主成分分析筛选出综合品质得分较高的组合。聚类分析将材料分为6类,结合判别分析构建了樱桃番茄品质判别函数,模型交叉验证显示正确判别率达到79.3%。此研究为樱桃番茄的品质评价提供了新思路。     

Prevalence of ophthalmic disease in blue‐eyed horses

A perception exists amongst referring veterinarians and the lay public that blue‐eyed horses have increased frequency of ocular disease. The aim of this retrospective study was to assess the prevalence of ocular disease in horses with blue or heterochromic eyes relative to those with brown eyes. The medical records of horses presenting to either the Comparative Ophthalmology services or Equine Medicine/Surgery services at 2 institutions were reviewed. Signalment, ocular and nonocular diagnoses were recorded. Ocular disease was divided into 4 categories: adnexa, cornea, intraocular/orbit and squamous cell carcinoma (SCC). Owners were contacted by telephone to confirm iris colour. Chi‐square analysis was used to compare group proportions. A total of 164 eyes of horses with ocular disease and 212 eyes of horses without ocular disease were included. Blue eyes were equally common in the ocular disease and nonocular disease groups (P = 0.265). There was no significant difference in the proportion of blue‐ and brown‐eyed horses when comparing the adnexal and corneal (P = 0.548), corneal and intraocular/orbit (P = 0.379) and adnexal and intraocular/orbit (P = 0.843) categories. A significant difference was detected in the proportion of blue‐eyed horses between the adnexal (P = 0.000), corneal (P = 0.033), intraocular/orbital (P = 0.000) and SCC categories, with a higher proportion of blue‐eyed horses in the SCC than in the other 3 groups. Horses with blue or heterochromic irides are more likely to develop ocular SCC than horses with brown irides, but are not more likely to have adnexal, corneal or intraocular/orbital disease or to be presented for evaluation of ophthalmic disease. Veterinarians should consider the results of this study when answering questions from the lay public regarding the predisposition of blue‐eyed horses to ocular disease.     

使樱花赏花期延长的日本引种品种的选育搭配研究

对武汉法雅园林集团有限公司从日本引进的39个樱花品种的成活率和花期进行了观测研究,筛选出了23个成活率在80%以上的花期不同的品种,为园林绿化工程中延长樱花赏花期的品种搭配设计提供参考依据。     

Pigmentation and eye migration in Atlantic halibut (Hippoglossus hippoglossus L.) larvae: new findings and hypotheses

Atlantic halibut juveniles, which have been fed Artemia during larval development, frequently demonstrate malpigmentation and impaired eye migration. This is in contrast to the high percentage of normally developed larvae fed copepods, reared under similar conditions. Nutrition is therefore an important component influencing larval development. Analyses of the nutrient composition of Artemia and copepods show that Atlantic halibut larvae fed Artemia probably receive sufficient amounts of vitamin A by converting canthaxanthin, while iodine may be deficient, possibly leading to interrupted thyroid hormone synthesis. An unbalanced fatty acid composition, such as high levels of arachidonic acid and low levels of docosahexaenoic acid, can be another limiting factor in Artemia. Vitamin A, fatty acids and thyroid hormones have all been shown to affect pigmentation in flatfish. They are ligands to nuclear receptors, thyroid hormone receptors, retinoic acid receptors, retinoic X receptors and peroxisomal proliferator‐activated receptors, which are members of the superfamily of steroid hormone receptors. The receptors interact with each other to promote gene expression that modulates proliferation and differentiation of cells. Our hypothesis is that these interactions are important for development during flatfish metamorphosis. Very little data exist on the topic of impaired eye migration. However, energy limitation, iodine deficiency and an unbalanced fatty acid composition have been proposed as possible explanations. Here, we review the literature on development of pigment cells and the possible mechanisms behind the effects of vitamin A, fatty acids and thyroid hormone on pigmentation and eye migration during development of Atlantic halibut larvae.     

Oxygen delivery to the fish eye: blood flow in the pseudobranchial artery of rainbow trout (<Emphasis Type="Italic">Oncorhynchus mykiss</Emphasis>)

Similar to gas secretion into the swimbladder, some teleosts also exhibit ocular gas secretion to supply their thick and avascular retina with oxygen. The process in the eye, however, is complicated by the fact that the retina is supplied with arterial blood only indirectly through the pseudobranch, a reduced gill arch of still unknown function. Approaches for closer analysis of the physiological implications of this serial blood supply arrangement and the associated process of O₂ release include complete unilateral vascular isolation of eye and/or pseudobranch while maintaining normal blood flow characteristics for undisturbed operation of the counter-current rete mirabile.Blood flow velocity in the afferent pseudobranchial artery (aPA; essentially equal to ophthalmic artery flow) of rainbow trout was measured by application of ultrasonic Doppler techniques. Accurate determination of flow rate in the untouched vessel was facilitated by mounting the Doppler crystal with a custom-made holder on the bone of the jaw and raw signal analysis by Fast Fourier Transformation for improved signal/noise ratio. Normal unilateral aPA blood flow was 746 l min^–1 kg^–1 body weight, (1.6% of cardiac output), the tissue-weight-specific blood flow was 3.6 ml min^–1 g^–1 for pseudobranch and 2.3 ml min^–1 g^–1 for the retina. Only about 28% of the oxygen potentially available with maximal activation of the Root effect is actually consumed in pseudobranch and retina. This generous supply of blood and the implicit safety margin may serve minimization of pH disturbances of retinal tissues, but may also come suitable during unilateral occlusion of supplying arteries for continued oxygen supply to the retinae. During contralateral occlusion, flow through the ipsilateral aPA increased to 136%. According to the normally low O₂ extraction, a minimal flow of 36% through bilateral anastomosis and contralateral ophthalmic artery may maintain complete contralateral oxygen supply.     

广西田阳县兴城村樱桃番茄裂果原因分析与对策

在对田阳县兴城村樱桃番茄裂果情况实地调查的基础上,系统分析总结造成樱桃番茄裂果的主要原因,并有针对性地提出防治对策。     

大连地区大樱桃常见缺素症状及防治对策

大樱桃是多年生木本果树,其根系分布较浅,且养分需求比较集中,常造成某些养分的缺乏。近年来在大连地区大樱桃种植区走访调查发现,钾、锰、镁、硼、铁等养分的缺素现象比较多,因此针对大樱桃以上缺素症状的识别和采取相应的防治对策是很有必要的,同时针对樱桃缺素发生的原因进行了深入的分析,以便于系统的对樱桃缺素进行综合防治。     

壳聚糖/琼脂涂膜处理对圣女果贮藏品质的影响

研究不同比例的壳聚糖/琼脂涂膜液和不同包装方式对圣女果的感官品质、甜度、硬度、酸度和失重率等品质特征的影响。采用壳聚糖、琼脂、醋酸不同配比的膜液对圣女果涂膜,在温度20±1℃,湿度为65%±1%的条件下储藏,测定圣女果的各项质量指标的变化情况,并与现有包装进行对比试验。实验结果表明,配比为壳聚糖0.7%,琼脂0.1%,冰醋酸2%,甘油3%的涂膜剂保鲜效果最佳。     

更昔洛韦眼用凝胶和阿昔洛韦滴眼液治疗单疱病毒性角膜炎疗效观察

目的探讨更昔洛韦眼用凝胶和阿昔洛韦滴眼液治疗单疱病毒性角膜炎的临床效果.方法单疱病毒性角膜炎患者104例均为单眼发病.根据治疗方案分为两组,采用阿昔洛韦滴眼液治疗患者52例为对照组,采用更昔洛韦眼用凝胶治疗患者52例为观察组,疗程3周,随访1a,比较两组患者的治疗时间、治疗效果、不良反应及复发情况.结果观察组患者浅层型、深层型、混合型单疱病毒性角膜炎治疗时间均明显少于对照组,观察组患者总有效率明显高于对照组,观察组患者不良反应发生率、复发率均明显低于对照组,差异具有统计学意义（P〈0.05）.结论更昔洛韦眼用凝胶和阿昔洛韦滴眼液均是治疗单疱病毒性角膜炎的有效药物.更昔洛韦眼用凝胶的治疗效果更好,可明显缩短患者的治疗时间,不良反应少,且复发率低,值得临床推广使用.     

YOGA护眼疗法对青少年假性近视的疗效观察

目的观察YOGA护眼疗法对青少年假性近视的临床疗效．方法将符合纳入标准的136名7～15岁青少年假性近视患者作为研究对象,YOGA护眼疗法为试验组,眼保健操组为对照组,比较两组研究对象视力恢复情况．结果对照组3个月后视力高于试验前,但差异无统计学意义（P〉0．05）;试验组3个月后视力高于试验前,差异非常显著,具有统计学意义（P〈0．01）;试验组3个月后治疗效果明显高于对照组试验后,两组疗效差异具有统计学意义（P〈0．01）,结论通过YOGA护眼疗法练习的试验组恢复效果明显高于对照组及试验前,表明YOGA护眼疗法对青少年假性近视恢复具有显著疗效．