金光杏梅果实生长动态观察研究

研究结果表明,金光杏梅果实生长发育动态呈“慢-快-慢-快-慢”的“3S”型曲线．整个发育过程可分为5个时期:幼果缓慢生长期、果实第一次迅速生长期、果实第二次缓慢生长期、果实第二次迅速生长期和果实熟前缓慢生长期。果实第二次缓慢生长期与果实硬核期相吻合,果实第一次迅速生长期和第二次迅速生长期是果实增长的两个关键时期。果实纵、横、侧径和果肉厚度与果实鲜重和体积变化曲线极为相似,经相关分析,果实纵、横、侧径和果肉厚度与果实鲜重的相关系数分别为0．9421**、0．9442**、0．9413**和0．9843**,与果实体积的相关系数分别为0．9391**、0．9462**、0．9373**和0．9824**,均呈极显著相关,说明它们是同步增长的。果核的生长发育动态呈“快-慢-停”的近“厂”型曲线,谢花后31d以前是迅速生长期;31d后进入缓慢生长期并开始硬化、变色:至59d达到固有大小和颜色,硬化结束,59d后停止生长。     

树冠中的黄金分割初步探析

将现实林冠底部截断面看作是以东西和南北长（冠长）为对角线的菱形，求算出菱形的面积（Slx），并将以最大冠长为直径的圆面积视为树冠的潜在面积或理论面积（Sy），采用GMB－Slx/Sy分别计算天山云杉（Picea schrenkiana var,tianshanico)人工幼林12块中心样方，1987和1993的2期树冠调查资料，发现：GMB符合“黄金分割”（0．599≤GMB≤0．637）的树冠较匀，而GMB不符合黄金分割（GMB＜0．599）的树冠则属于偏冠。同时，GMB是否符合黄金分割还能反映出林木个体间的竞争格局，并且GMB可以单独作为一个指标应用到中幼林的抚育间伐等领域。因此，探讨树冠中的黄金分割具有重要的研究价值和应用潜力。     

农科金心蝴蝶兰多点比较试验初报

采用常规育种和生物克隆快繁技术,经过7年研究培育出具有花大色艳、抗性强、适应性好等优良性状的蝴蝶兰黄花系新品种农科金心。该品种植株株型整齐,花朵排列整齐对称,花型丰满圆润,平均花径9.5cm,侧瓣纯黄无杂色;唇瓣深红,平均单梗花朵数9.2朵,80%以上植株在8~12朵范围;抗病性较强,耐热尧耐寒性比对照增强。经广东省多点多批比较种植试验,综合性状稳定遗传。     

昆明市城市森林结构模式在园林中的应用——以金牛公园为例

位于昆明市中心的金牛公园定位为城市生态绿地。文章介绍了该公园的森林结构以及植物群落组成,并分析了公园的生态效益。通过问卷调查,92.2%的市民对金牛公园的景观效果满意。提出了城市森林结构模式在园林应用与发展中的对策。     

森林生态旅游环境解译服务游客态度调查--以金殿国家森林公园为例

通过实地考察、调查问卷等方法,以金殿国家森林公园为研究案例,进行游客对解译服务内心期望重要程度和实际体验满意程度调查,了解游客对解译媒体、媒体设计、解译内容等的选择倾向,分析不同性别、不同年龄、不同文化层次游客的偏好差异,并提出完善解译媒体、系统培训人员、建立教育基地等的构建对策。     

关于浙江金石拓片的认识与思考——从其特点、价值、利用角度探索

金石拓片是地方文献的特殊载体之一,通过对浙江的金石拓片的特点、价值的认识和思考,指出对金石拓片开发和利用,发挥其应有的价值。     

Long Term Rearing of Cuttlefish in a Small Scale Facility

Cephalopods are arguably the most complex and fascinating aquatic invertebrate taxa. Except for a few well known exceptions, this group of organisms has been a challenge to study primarily due to difficulties in rearing and maintaining these animals in a small laboratory setting. Our knowledge about cephalopod rearing comes mainly from large marine centers, with much less known about small scale rearing facilities. This paper describes a bench top (ca. 450 litre) aquarium system that is relatively inexpensive, easy to maintain, and suitable for long term rearing of cuttlefish in the laboratory. This closed aquarium system uses artificial sea water and a biological filter to remove/recycle nitrogenous wastes. The simple design of this system can be easily replicated by inland researchers interested in studying cuttlefish but who have been thwarted by the lack of suitable housing facilities. This revised version was published online in August 2006 with corrections to the Cover Date.     

The effects of tank colours on the growth and survival of cuttlefish (Sepia officinalis,Linnaeus 1758) hatchlings and juveniles

The effects of different tank colours (white, yellow sandy and black) on the growth, mortality and biomass production were studied for hatchling and early juvenile cuttlefish. For hatchlings, the use of different colour tanks did not promote differences in growth due to the higher variability (standard deviation) found in the white‐ and sand‐coloured tanks. Black tanks promoted the lowest and highest values for total mortality and biomass respectively. For juveniles, the use of different tank colours promoted different growth (P<0.05), but not mortality. Black tanks promoted the best results in terms of growth and biomass. The results obtained in the present study advise the use of black (or dark colour) tanks in the hatchling and early juvenile stages to reduce the standard deviations associated with growth, mortality and biomass production. This will contribute to minimize problems associated with slow and fast growers and competition.     

New urban habitat for endangered humpback whales: San Francisco Bay

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The electroretinographic phenotype of dogs with Golden Retriever muscular dystrophy

Objective To characterize the flash electroretinogram (ERG) in the Golden Retriever muscular dystrophy (GRMD) dog and to compare the results with those from a control group of Golden Retrievers. To investigate whether similar abnormalities of the ERG as those found in a majority of human patients with Duchenne muscular dystrophy (DMD) are also observed in the GRMD dog, the canine model for DMD. Animals Five GRMD dogs and five age‐matched clinically normal Golden Retrievers. Procedure An ophthalmic examination was carried out prior to performing electroretinography under general anesthesia. Rod, combined rod–cone and oscillatory potentials responses were recorded after dark adaptation. Responses to 30‐Hz‐flicker were recorded after light adaptation. The ERG responses of the GRMD dogs were compared with those of the control dogs by use of a Wilcoxon signed rank test. Results GRMD dogs had significantly reduced a and b‐wave amplitudes after dim white flash stimuli (rod response) and reduced a‐wave amplitude after bright white flash stimuli (rod–cone response). Conclusion and clinical relevance The ERG abnormalities observed in the GRMD dog suggest a dysfunction in the rod signaling pathway. These ERG alterations are different from those observed in human patients with DMD.