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61.
中国20世纪50年代中期对社会主义道路的探索从具有社会主义本质特征的制度层面来看,集中体现于陈云在中共八大发言中提出的“三个主体、三个补充”。由于八大仍把消灭资本家所有制和个体劳动者所有制的残余规定为党要继续实现的任务,这就使当年的探索没能摆脱苏联模式的框架,探索也因此中断以至逆转。中共十一届三中全会以后是邓小平首先从社会主义模式的角度提出问题,全党才得以摆脱苏联模式的理论和框架的影响,从而逐步摸索和确立了中国特色社会主义的基本框架。  相似文献   
62.
Two stories are told simultaneously: one that may have been, and one that yet might be. The story of the voyage that might have been is based on archaeological evidence provided by the earliest shipwreck discovered in the New World. These two stories are set in different eras to demonstrate certain constants in the human drive to explore the unknown, in the methods used, and in the consequences encountered.  相似文献   
63.
From long-term stratigraphic records in Pacific Island archaeological sites, researchers have documented alterations to molluskan species richness and abundance, decreases or increases in mollusk shell size and, in rare cases, human foraging may have contributed to the extirpation of mollusk taxa. Mollusks perform critical ecosystem functions in tropical intertidal environments, including improving water quality through filtration, regulating algal cover, and increasing habitat and substratum complexity through ecosystem engineering. These critical ecosystem functions can be negatively affected by human foraging, possibly contributing to decreased resilience of coral reefs to climatic alterations. We review modern ecological research on human impacts to mollusks and intertidal ecosystems that illustrates the mechanisms and effects of human foraging. We then examine centuries to millennial scale archaeological records from the Pacific Islands to understand long-term, time-averaged trends in human impacts to intertidal ecosystems.  相似文献   
64.
The use of islands as ‘model systems’ has become particularly relevant for examining a host of important issues in archaeology and other disciplines. As papers in this special issue of the Journal of Island and Coastal Archaeology demonstrate, islands can serve as critical and ideal analytical platforms for observing human populations in the past and their evolutionary histories within complex and insular human ecodynamics. In this paper we address the issue of how islands are also important models for future sustainability and as corollaries for the survival of humans generally. In a sense, island cultures and ecosystems can be seen as microcosms of the issues we have faced as humans, and provide important insights for understanding the fate of our species, particularly as it pertains to the exploration and colonization of new worlds.  相似文献   
65.
本文对毛泽东探讨中国社会主义发展阶段的理论和实践 ,作了比较系统的论述 ,特别是对“大过渡”的理论及其危害作了深入的分析 ,在指出“大过渡”理论错误时 ,也指出这中间出现过“阶段论”的思想火花。  相似文献   
66.
Katja Neves 《对极》2010,42(3):719-741
Abstract: This paper engages critically with the monolithic presentation of whale watching as the antithesis of whale hunting. It begins by tackling the reductive and homogenized portrayal of whale watching in mainstream environmental discourse as diametrically opposite to whale hunting and argues that such discourse likely obscures the existence of bad whale watching conduct. Next it reveals significant continuities between whale hunting and whale watching, especially the fetishized commoditization of cetaceans and the creation of a metabolic rift in human–cetacean relations. In both contexts nature is produced first and foremost according to capitalist principles, which problematizes the pervasive assumption that whale watching correlates primarily and directly with conservation. Finally, the paper examines two different business models and the production of distinct ecological and community development effects. The results of the comparison justify the need for more critical and effective environmental non‐governmental organization approaches to cetourism vis‐à‐vis nature conservation goals.  相似文献   
67.
Wretman, L. & Kear, B.P., 2013. Bite marks on an ichthyodectiform fish from Australia: possible evidence of trophic interaction in an Early Cretaceous marine ecosystem. Alcheringa 38, 000–000. ISSN 0311-5518.

A well-preserved fish skull from late Albian deposits of the Allaru Mudstone near Richmond in Queensland displays a conspicuous V-shaped pattern of indentations, punctures and depression fractures consistent with a vertebrate bite trace. This is the first direct evidence of trophic interaction between vertebrates within an Early Cretaceous marine ecosystem from Australia. The specimen is taxonomically referable to the large-bodied (ca 1?m snout–tail length) ichthyodectiform Cooyoo australis, but the size and spacing of the tooth marks is incompatible with attack by a conspecific individual. The lack of osseous growths concordant with healing also suggests that the bite occurred shortly before or after the animal’s death. Comparison with the dentitions of other coeval vertebrates indicates compatible tooth arrangements in longirostrine amniote predators such as polycotylid plesiosaurians, ornithocheiroid pterosaurs and especially the ichthyosaurian Platypterygius. The implications of this as a potential predator–prey association are that Early Cretaceous actinopterygians occupied middle-level trophic niches and were in turn consumed by higher-level amniote carnivores, similar to many extant marine vertebrate communities of today.

Lovisa Wretman [lovisa.wretman@ebc.uu.se], Subdepartment of Evolution and Development, Department of Organismal Biology, Uppsala University, Norbyvägen 18A, SE-752 36 Uppsala, Sweden (address for correspondence); Benjamin P. Kear [benjamin.kear@geo.uu.se], Palaeobiology Programme, Department of Earth Sciences, Uppsala University, Villavägen 16, SE-752 36 Uppsala, Sweden. Received 8.8.2013, revised 17.9.2013, accepted 23.9.2013.  相似文献   
68.
Following a right cerebral stroke, the German artist Anton Raederscheidt produced a remarkable series of self-portraits that depicted his severe visual neglect and gradual recovery. These distorted images, like those drawn by others with this disorder, inform us about lateral balance in art and why it is common in the art of cultures separated in time and space. After describing how artists in various cultures have employed lateral balance, I present Arnheim’s view that this aspect of art is the result of visual forces generated by the brain. Following a brief history of visual neglect, I present evidence that this disorder provides us with clues to the origin of the visual forces responsible for lateral balance in art. The relevant brain mechanisms control exploration of visual space by integrating orienting movements with visual spatial information. The prevalence of lateral balance in art becomes understandable when we consider that these brain mechanisms evolved to promote survival in our vertebrate ancestors. I end with a speculative neurological account of the aesthetics of lateral balance – why it is pleasing and its absence is displeasing.  相似文献   
69.
Published and archival sources are examined to elucidate the career of William Gordon Burn Murdoch, artist, bag‐piper, explorer, geographer, hunter, Scottish nationalist, traveller, whaler and writer. Burn Murdoch's diverse contributions to geography are discussed, as are the roles he played in the Royal Scottish Geographical Society and other Scottish scientific and literary societies. A preliminary list of his extant original works of art is included.  相似文献   
70.
In geographic scholarship, urban exploration (urbex) has been examined as an embodied practice with radical potential for re‐appropriating urban spaces. However, geographic literature on urban exploration has largely ignored the particular qualities of the urban explorer as a subject and neglected feminist scholarship on embodiment and social difference. Based on our examination of both popular and academic treatments of urbex we identify a prevalent and largely unacknowledged culture of masculinism. We ask: Whose bodies explore? What counts as experience? What constitutes the exchange between body and place? And, with what effects? Addressing these questions permits considerations of exclusions and marginalizations left unaddressed in much geographic literature on urbex.  相似文献   
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