Testate amoebae as predators of nematodes

Testacea were observed ingesting nematodes in the litter horizons of native forests in New Zealand. Nematodes were most commonly attacked from the tail end but some specimens were attacked at mid-body. Nematodes with damaged tails were recovered in greatest numbers from the highest, wettest site sampled. Nebela (Apodera) vas (Certes, 1989) and Difflugia sp. (possibly lanceolata Penard, 1890) were the predators; both species were redescribed using light and scanning electron microscopy and morphometry. Most damaged nematodes were Ironus sp. but Clarkus, Tobrilus, Iotonchus, Cobbonchus, Dorylaimus and Plectus were also attacked. Literature on testacean feeding strategies was reviewed briefly.     

一种语言判断矩阵元素与优先权重的逻辑关系

提出了一种语言判断矩阵的元素与优先权重的含参数的逻辑关系,并对参数的选取进行了分析,最后给出了算例说明.     

Artificial Feeding and Laboratory Rearing of Endangered Saproxylic Beetles as a Tool for Insect Conservation

Conservation of threatened animals is frequently limited by lack of knowledge about their ecological preferences, and often artificial feeding is one of the few chances to save endangered species. We investigated the possibility to artificially feed two endangered flat bark beetles dependent on dead wood for their diet—namely, Cucujus cinnaberinus (Scopoli, 1763) and Cucujus haematodes Erichson, 1845—by examining their dietary preferences, life cycle duration, and survival in laboratory conditions. Individuals of the two species were caught in the wild and larvae and adults were fed in laboratory conditions by live or dead prey. Three species of saproxylic beetles: two cerambycids (Acanthocinus griseus Fabricius, 1793 and Rhagium inquisitor Linnaeus, 1758), one scolytid (Ips sexdentatus Börner, 1776) one tenebrionid (Tenebrio molitor (Linnaeus, 1758)) one dipteran (Lucilia sericata (Meigen, 1826)) and one ant (Lasius sp. Fabricius, 1804) were used as prey, with minced meat as a control. Our results indicated high survival and no difference in prey choice between the two flat beetle species. Larvae and adults preferred dead prey, but no significant preference was detected among dead prey taxa, supporting the hypothesis that the two species are opportunistic scavengers. Comparing data with previous results, both species and their developmental stages should be classified as obligate saproxylic organisms with preference to the dead and decaying organic material. Successful artificial feeding and rearing of these endangered species, followed by the release in the wild through rescue or reintroduction programs, therefore appear relevant for their protection and future conservation.     

我国上市公司融资结构与优化对策

现代资本结构理论揭示了企业的最优融资顺序为:内部融资——债权融资——股权融资,而我国上市公司的融资行为与现代企业资本结构理论并不一致,表现出较强的股权偏好现象。本文对这种现状的原因进行了分析,并针对这种不合理融资结构所带来的弊端提出了相关建议。     

Oviposition preference of Anoplophora glabripennis emerging from five host tree species under field conditions

The Asian longhorned beetle （ALB）, Anoplophora glabripennis （Motschulsky） is a polyphagous woodborer of hardwood trees. In order to well understand the oviposition preference of A. glabripennis emerging from different larval host tree species, we selected five common host tree species in the field and evaluated its oviposition preferences. The five host tree species are Acer negundo （AN）, Salix matsudana f. lobato-glandulosa （SM）, Populus nigra L. var. thevestina （Dode） Bean （PN）, P. simonii × P. pyramidalis cv. Opera 8277 （PS） and P. alba var. pyramidalis （PA）. Results show that adult beetles emerging from these five tree species almost have the same oviposition phenomenon. All adult beetles, except those emerging from PS, chewed the highest potential sites and laid most eggs on AN trees. Adult beetles emerging from AN, PN, PS and PA did not chew any sites nor laid any eggs on PA trees. These results showed that adult A. glabripennis emerging from the five host tree species did not show any clear oviposition preference for their larval host tree species in the field but they did present the most obvious preference for AN and the lowest preference for PA.     

Inheritance of Eye Pattern and Seed Coat Colour in Cowpea (Vigna unguiculata [L.] Walp.)

The F₂ progenies of crosses between several cowpea (V. unguiculata) lines were investigated for variation of eye pattern and seed coat colour. It was found that three (W, H, O) and five (R, P, B, M, N) major genes control eye pattern and seed coat colour, respectively. The recessive gene (GO) for restricted eye pattern enables the underlying basic white or cream seed coat colour to be observed. A similar effect is obtained with the recessive gene (rr) for colour expression. The expression of mottling (V), possibly a seed coat pattern, may for be observed when it is combined with the genes for certain eye patterns. The significance of these findings in breeding for consumer preference for specific seed coat colour is discussed.     

基于感知和行为视角的校园滨水景观偏好研究 ——以福建农林大学观音湖为例

基于人群感知和行为视角,以福建农林大学观音湖为研究对象,通过拍照试验、访谈问卷、扫描观察收集数据,采用词频分析、照片分析、GIS技术分析,分析景观元素、景观感知以及驻留点、观景点、景点、视线廊道的空间特征,以获得游览者对滨水景观偏好特征,采用核密度分析,得到游客景观点的热点分布。结果表明,词频分析预测出游客关注湖区丰富的景观元素,以静态观赏和行进式观赏方式游览观音湖,舒适的湖区环境让游客感到心情愉悦、平静;空间角度,游览者的驻留点分布与观景点分布具有显著的一致性,表明优美的空间环境和良好的观景位置有利于游客驻留行为的产生;游览者对滨水景观的偏好是由“丰富性—功能性—特色性”三大属性特征相互协调、影响而形成的三维耦合结构模型。     

Habitat use and movement patterns of small (age‐0) juvenile Pacific bluefin tuna (Thunnus orientalis) relative to the Kuroshio

The habitat use of Pacific bluefin tuna (Thunnus orientalis; PBF) in nursery waters off the southern coast of Japan was investigated using archival tags over a 3 year study period (2012–2015), and the data were used to examine the free‐ranging habitat preferences of PBF and the relationship between their horizontal movements and the path of the Kuroshio off the Pacific coast of Japan. The path of the Kuroshio fluctuated seasonally, leading to changes in water temperature that strongly influenced the habitat use of small PBF (2–3 months after hatching). Most PBF were present in coastal waters inshore of the path of the current, and their habitat use changed in response to the distance of the current from the coast. The Kuroshio typically flowed along the coast from summer to autumn, and PBF remained in the coastal waters off Kochi Prefecture during this period. In contrast, PBF quickly moved eastward in winter when the current moved away from the coast. Throughout the winter and spring, the area of habitat use extended widely from the eastern end of the southern coast of Japan (the Boso Peninsula) to the offshore Kuroshio‐Oyashio transition region. These findings suggest that the seasonal habitat use and movement behavior of juvenile PBF are influenced by the distance of the Kuroshio axis from the coast, and the ultimate drivers are likely variations in oceanographic conditions and prey availability along the southern coast of Japan.     

水解单宁对暗纹东方鲀摄食偏好、消化代谢和抗氧化能力的效应

为了解菜粕替代鱼粉后单宁的作用,配制4组等氮等能饲料饲喂初重(39.84±3.09) g的暗纹东方鲀8周。以含43%鱼粉的实用基础饲料T0为对照;另设置3个不同的鱼粉用量组,用酪蛋白平衡蛋白质含量,并添加0.25%(T1)、0.75%(T2)和1.25%(T3)的水解单宁,使酪蛋白:水解单宁≈菜粕中蛋白含量:菜粕中单宁含量=16.8∶1。结果显示,随饲料中水解单宁添加量的增加,增重率呈上升趋势,饲料系数显著下降;肌肉粗脂肪含量T2组显著高于T0及T1组,对照组氨基酸水平显著高于其他组。肝脏抗氧化指标中,T0组过氧化氢酶(CAT)活力显著低于其他组,总抗氧化能力(T-AOC)则显著高于其他组,T3组丙二醛(MDA)含量和超氧化物歧化酶(SOD)活性显著高于其他组。血清抗氧化指标中,3个单宁组MDA含量均显著高于对照组,过氧化氢酶(CAT)活力显著下降。随饲料中水解单宁添加量的增加,血清谷丙转氨酶(ALT)活性先升后降,与肝脏中趋势一致;T1组白蛋白(ALB)含量高于T0及T3组,显著高于T2组,T1组总蛋白(TP)含量高于T0组,显著高于T2及T3组。T1及T2组肠道淀粉酶活性显著高于T0组,胃和肠道中的蛋白酶活性随水解单宁添加量的增加显著上升,胃脂肪酶活性显著下降。T3组苦味受体T2R1表达量在舌尖和肠道均显著高于对照组;肝脏热休克蛋白HSP70表达量T0组显著高于T3;摄食偏好实验中,驯化前暗纹东方鲀摄食偏好随水解单宁添加量的增加显著下降,驯化8周后,4组实验鱼对T2饲料的偏好程度均显著高于T0,T0饲料高于T1和T3组。研究表明,添加1.25%及以下水解单宁对暗纹东方鲀生长无负面影响,一定程度上对饲料有节约作用;添加水解单宁会改变鱼体对蛋白质、脂肪和糖类的消化及蛋白质合成代谢,添加量在1.25%时会损伤抗氧化能力和抗应激能力;用含有水解单宁的饲料驯化暗纹东方鲀可显著提高其对水解单宁添加量为0.75%的饲料的偏好程度,并提高对苦味的接受能力。