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51.
The impact of water temperature(24, 27, 30 and 33℃) and salinity(15, 20, 25, 30 and 33) on oxygen consumption(OCR) and ammonium excretion rate(AER) of ♀ Epinephelus fuscoguttatus ×♂ E. lanceolatus hybrid grouper juveniles(9.39 ± 0.07 g) were investigated under the fed and un-fed conditions. The results showed that the OCR and AER were significantly(P < 0.05) affected by temperature and salinity under both fed and un-fed conditions. When temperature was 24–33℃, the OCR and AER of fed hybrid grouper juveniles were 85.68%–129.52% and 125.78%–287.63%, respectively, higher than those of un-fed hybrid grouper juveniles. The O/N ratio, protein use(P_u), Q10(respiration) and Q10(excretion) of fed hybrid grouper juveniles were 14.43–24.01, 28.35% – 48.48%, 1.69 and 3.01, respectively. The O/N ratio, P_u, Q10(respiration), Q10(excretion) of un-fed hybrid grouper juveniles were 20.39 – 31.79, 22.16% – 34.34%, 1.23 and 1.17, respectively. When salinity was 15–33, the OCR and AER of fed hybrid grouper juveniles increased by 87.42% – 116.85% and 215.38% – 353.57%, respectively, over those of un-fed hybrid grouper juveniles. The O/N ratio and P_u of fed hybrid grouper juveniles were 14.48 – 17.78, 39.36% – 49.43%, respectively. The O/N ratio and Pu of un-fed hybrid grouper juveniles were 20.39 – 31.79 and 22.16% – 34.34%, respectively. The specific dynamic action(SDA) of hybrid grouper juveniles was mainly related to protein metabolism. The results had a guiding significance to the large-scale intensive aquaculture of hybrid grouper juveniles.  相似文献   
52.
Two key figures analyzed in Donna Haraway’s monograph, Primate Visions: Gender Race and Nature in The World of Modern Science (1989) warrant further analysis in the emerging cyber politics of environmental conservation. These figures are Koko, a female lowland gorilla born in the San Francisco Zoo and her companion Dr. Francine (Penny) Patterson, a developmental psychologist who taught Koko how to communicate with a modified form of American Sign Language (ASL). Nine years after Haraway’s initial analysis, Koko and Patterson became early examples of conservation-related Web 2.0 engagement with their unprecedented inter-species America Online chat room encounter with 7811 member participants. Today, Koko has a Twitter account (@kokotweets), a Facebook page, a YouTube channel and a website where users watch videos of Koko celebrating birthdays and donate to ‘distant’ conservation projects. One project site is a gorilla reserve in Cameroon and another is a former pineapple plantation turned private nature preserve in Maui, Hawai’i. Inspired by recent analytical work in animal geographies and feminist political ecology, this article explores complex landscapes of caring, aging and conservation in a time of proliferating social media engagement from colonized sites of enduring privilege. The article argues that new media adds layers of violence, disciplinary techniques and co-dependence to the aging bodies, caring practices and landscapes that Koko, Patterson and others inhabit in California and in the proposed physical spaces of a repurposed pineapple field in Maui.  相似文献   
53.
Lhx1基因对于哺乳动物卵巢缪勒氏管的形成具有重要作用, 但鱼类中的报道仅限于其在体轴和肾脏形成中的作用, 尚未见到其与性别及性腺发育相关的报道。本研究克隆获得了牙鲆(Paralichthys olivaceus)Lhx1aLhx1b开放阅读框(ORF)序列, 长度分别为1224 bp 和1206 bp (GenBank 注册号为:JX999940、JX999941), 同源序列比较显示牙鲆Lhx1aLhx1b基因均具有两个LIM 及一个HOX 结构域, 符合Lhx1进化保守性。这两个基因在牙鲆雌、雄成鱼各组织RT-PCR 差异表达谱不尽相同, Lhx1a在精巢中弱表达, 卵巢中不表达, 在其他组织中雌、雄表达谱差异不大, 都只在脑和眼组织有弱表达;而Lhx1b的表达在性腺中相对较高, 且卵巢的表达量高于精巢。进一步检测牙鲆Lhx1aLhx1b在雌、雄性腺发育各期的表达谱, 发现这两个基因表达集中于Ⅲ、Ⅳ期性腺, Lhx1a在精巢中弱表达, Lhx1b卵巢中的表达明显高于精巢, 而在Ⅰ、ⅡII、Ⅴ期性腺几乎均不表达。由此推断牙鲆Lhx1aLhx1b均为性别相关基因, 但在两性性腺发育中的作用可能各有不同。  相似文献   
54.
The relationship between the composition of the invertebrate drift fauna and the feeding habits of the common river galaxias Galaxias vulgaris and the upland bully Phily pnodon breviceps was examined in the Glentui River, Canterbury, New Zealand, between 1500 h on 12 November and 1500 h on 13 November 1971. The drift consisted of both night‐active and day‐active components. Galaxias vulgaris fed mainly at night, with peaks of feeding at dusk and dawn. Philypnodon breviceps had two peaks of feeding, at midday and midnight, between the peak feeding times of G. vulgaris. Feeding of G. vulgaris on its major food items coincided with the presence of the food items in the drift, whereas feeding of P. breviceps did not coincide with the occurrence of the food items in the drift. It is concluded that G. vulgaris is primarily an open‐water feeder and that P. breviceps searches for food on the river bed.  相似文献   
55.
Armed with a scholarship to find an answer to the question “What is geography?” Simion Mehedin?i's studies took him to continental Europe's three main centers of geographic thought: Paris, Berlin, and Leipzig. We explore how his innovative ideas flourished, especially in Leipzig under Ratzel. The first Romanian geographer, Mehedin?i, must be credited with having defined geography as a science of mutual relationships between geospheres. This thinking reached its pinnacle in two complex books, Terra and Ethnos, the contents of which we synthetically explore. We also trace the unfavorable historical and geopolitical conditions that led to this pioneering work being little recognized worldwide.  相似文献   
56.
Psychoanalysis has profoundly influenced those social theories that inform qualitative methodology in human geography. Yet many geographers are skeptical about the value and viability of psychoanalytic methodology because of its alleged reductionist causal explanations and relativistic interpretations of data. Drawing on the work of Slavoj ?i?ek, which affirms Jacques Lacan's undermining of the dualism of causality versus sense, this article illustrates the potential value of Lacanian psychoanalysis as a qualitative methodology in geography. Using a methodological case study from my research on Jamaican tourism, I illustrate how we can locate a Lacanian understanding of the drives in the interactions between tourists and hotel workers. In so doing, the article provides new insights into the enduring allures of tourism's commodity-form by focusing on how the object petit a—a chimerical object that incites desire and an unattainable object that the drives encircle—takes place in customer service and entertainment activities.  相似文献   
57.
基于J2EE的数字预案查询系统研究   总被引:1,自引:0,他引:1  
简要介绍了城市公共安全应急平台的建设背景;详细论述了公共安全应急平台数字预案查询系统的建设,提出了基于J2EE的数字预案查询系统建设方案;展示了该数字预案查询系统的界面。  相似文献   
58.
广东博罗县小金河植物区系研究   总被引:1,自引:0,他引:1  
王英强  陈邦余 《热带地理》1995,15(4):350-361
本区计有野生维管束植物172科、532属、978种(包括变种、变型)。发现2新种,1新变种和3个广东新记录种。本区系的表征科为山茶科、壳斗科、桑科、芸香科、紫金牛科、樟科等,这些科大都是热带-亚热带分布式的,代表了本区系的性质。在属的地理成分中,本区以热带成分173属(占总数的35.2%)和热带-亚热带成分169属(占总数的34.4%)为主,说明了本区系具有由亚热带向热带过渡的南亚热带特征。本区与  相似文献   
59.
60.
Oracle9i空间数据存储的研究   总被引:2,自引:1,他引:2  
介绍了Oracle9i实现GIS空间数据和属性数据一体化存储的原理,重点阐述了地理空间各类实体的Oracle数据库存储结构,并给出了基于SQL—PLUS和MapX数据上载的实例。  相似文献   
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