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1.
Abstract

A mapping methodology is presented here that allows the practical implementation of synphytosociological and geosynphytosociological surveys. The proposed methodology consists in carrying out synrelevés from vegetation maps produced through the use of geographic information system (GIS). Such mapping has the great advantage of allowing the overlaying of the study area map with many thematic maps that are particularly useful in the definition of the areas of potential vegetation. In the present case, the use of solar radiation maps is proposed, as these are more representative than aspect maps (exposure) of the actual conditions of the mapped areas. Indeed, the main ecological factors that delimit the ecological niche of plant communities, the vegetation series and the geosigmeta are defined qualitatively and quantitatively. The methodology is here applied to an area of the Italian Adriatic coast that has a great diversity of environmental conditions. The conclusions confirm that the proposed methodology allows predictive models of the plant landscape units (geosigmeta) to be obtained with great precision; they can be mapped and quantified in concrete terms insofar as they are defined through multidimensional correlations.  相似文献   

2.
Abstract

Few members of the Pleistocene megafauna have been as extensively studied as cave bears. Multidisciplinary research into cave bears has provided insights into their morphology, ecology, and evolution. Genetic studies have profited from the availability of large numbers of well-preserved remains. As a result, ‘ancient DNA (aDNA)’ from cave bears has provided significant insights into cave bear ecology, phylogeography and even potential causes of their extinction. Here I review the contributions that genetic research has made to our understanding of cave bear biology and evaluate the potential that new, genomic tools provide to shed further light onto how these iconic representatives of the Pleistocene megafauna lived and died.  相似文献   

3.
Hilgendorf’s (1866) publication on the phylogenyof Planorbis multiformis from Steinheim, Swabian Mountains, is one of the most important contributions of paleontology to early Darwinism. At the same time it helped to lay the foundation for paleontological phylogenetics. Hilgendorf’s unpublished dissertation of 1863, the newly rediscovered collection to his dissertation and the document-file ofHilgendorf’s graduation from Tübingen University help to trace back the origin of Hilgendorf’s ideas.Hilgendorf’s collection contains the oldest phylogenetic tree, which is known so far.  相似文献   

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We provide here insights on the life and work of Berger C. Mayne (1920-2011). We remember and honor Berger, whose study of photosynthesis began with the most basic processes of intersystem electron transport and oxygen evolution, continued with application of fluorescence techniques to the study of photophosphorylation and the unique features of photosystems in specialized cells, and concluded with collaborative study of photosynthesis in certain nitrogen fixing symbioses. Berger loved the outdoors and was dedicated to preserving the environment and to social justice, and was a wonderful friend.  相似文献   

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The problem of plant individuality is something which has vexed botanists throughout the ages, with fashion swinging back and forth from treating plants as communities of individuals (Darwin 1800; Braun and Stone 1853; Münch 1938) to treating them as organisms in their own right, and although the latter view has dominated mainstream thought most recently (Harper 1977; Cook 1985; Ariew and Lewontin 2004), a lively debate conducted mostly in Scandinavian journals proves that the issues are far from being resolved (Tuomi and Vuorisalo 1989b; Fagerström 1992; Pan and Price 2001). In this paper I settle the matter once and for all, by showing which elements of each side are correct.  相似文献   

8.
This work describes a practical way to optimize the high level of the chef creativity to produce rational approaches to food design. It is particularly focused on the preparation of two dishes: bubbly juice and false skin. For the first dish, three samples were prepared with egg white protein (EWP) and xanthan gum at pH 4.6 and pH 7.0. At pH 4.6 (isoelectric point), there were substantial differences of the interfacial dilational modulus of EWP when xanthan gum was added. At 1 mg/ml xanthan, the system showed a very strong interface (high viscoelasticity) compared to the other samples. Measuring half drainage time revealed which samples were the most stable. The properties discussed were related to stability. For the false skin dish, edible films were made by gelatin extracted from cod skins (A solution) and a mixture of cod skin gelatin and commercial gelatin (AG solution). The results showed that tensile strength (TS) of gelatin films increases almost by 25%, elongation at break (EAB) by 14%, and the Young modulus (E) by almost 100% when increasing protein concentration. To confirm water plasticizer effect, the results were compared to a gelatin film made with 30% glycerol (plasticizer). Water content affects to a great extent the mechanical properties of the films. Finally, images of the dishes are presented in order to have a full view of the purpose and the results obtained. This research has been supported by the Department of Agriculture and Fisheries from the Basque Government. This work was presented at the conference Delivery of Functionality in Complex Food Systems, Amherst, USA, October, 2007.  相似文献   

9.

Anniversaries

Vladimir V. Frol’kis (1924–1999)  相似文献   

10.
Toward the end of the 1930s, Bernhard Rensch (1900–1990) turned from Lamarckism and orthogenesis to selectionism and became one of the key figures in the making of the Synthetic Theory of Evolution (STE). He contributed to the Darwinization of biological systematics, the criticism of various anti-Darwinian movements in the German lands, but more importantly founded a macroevolutionary theory based on Darwinian gradualism. In the course of time, Rensch’s version of the STE developed into an all-embracing metaphysical conception based on a kind of Spinozism. Here we approach Rensch’s “selectionist turn” by outlining its context, and by analyzing his theoretical transformation. We try to reconstruct the immanent logic of Rensch’s evolution from a “Lamarckian Synthesis” to a “Darwinian Synthesis”. We will pay close attention to his pre-Darwinian works, because this period has not been treated in detail in English before. We demonstrate an astonishing continuity in topics, methodology, and empirical generalizations despite the shift in Rensch’s views on evolutionary mechanisms. We argue that the continuity in Rensch’s theoretical system can be explained, at last in part, by the guiding role of general methodological principles which underlie the entire system, explicitly or implicitly. Specifically, we argue that Rensch’s philosophy became an asylum for the concept of orthogenesis which Rensch banned from evolutionary theory. Unable to explain the directionality of evolution in terms of empirically based science, he “pre-programmed” the occurrence of human-level intelligence by a sophisticated philosophy combined with a supposedly naturalistic evolutionary biology.
Georgy S. LevitEmail:
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Animal husbandry and working conditions for livestock farmers have changed significantly in recent years as agriculture has been exposed to economic as well as health, environmental and ethical challenges. The idea of interdependent welfare between humans and animals is more relevant now than ever. Here, we innovatively bridge two disciplines—ergonomics and applied ethology—to achieve an in-depth observational understanding of real husbandry practice (by farmers, inseminators, vets) at work. Ergonomics aims to gain a detailed understanding of human activity in its physical, sensitive and cognitive dimensions in relation to a task. It also aims to transform work situations through a systemic approach drawing on multiple levers for change. Here, we examine how this analysis holds up to the inclusion of animals as an integral component of the livestock farmer’s work situation. Applied ethology studies behaviours in animals managed by humans. It aims to understand how these animals perceive their environment, including how they construct their relationship with the livestock farmer. This paper proposes an original conception of the human–animal relationship in animal husbandry that employs core structural concepts from both disciplines. From an ergonomic point of view, we address the human–animal relations by examining the relationship between ‘prescribed’ and real work practices, between work and personal life situation, between professional task and human activity. On the applied ethology side of the equation, the human–animal relationship is a process built through communication and regular interactions between two ‘partners’ who know each other. The goal is to understand how each partner perceives the other according to their multimodal sensory world and their cognitive and emotional capacities, and to predict the outcome of future interactions. We cross-analyse these scientific views to show, based on examples, how and in what way they can intersect to bring better analysis of these human–animal relationships. We reflect on common working hypotheses and situated observational approaches based on indicators (behaviour and animal and human welfare/health). This analysis prompts us to clarify what human–animal relational practice means in animal husbandry work, i.e. a strategy employed by the livestock farmer to work safely and efficiently in a healthy environment, where the animal is treated as a partner in the relationship. In this perspective, the challenge is for the livestock farmer’s activity to co-build a positive relationship and avoid being subject to this one.  相似文献   

13.
Large population declines were reported for the thick-billed murre (Uria lomvia) in Greenland for the period 1930s–1980s, but no national status has been published for the past 20 years. Meanwhile, the murres have gained more protection and several human-induced mortality factors have been markedly reduced. Here, we give an updated status based on the past 30 years of murre count data. The total Greenland population in 2011 was estimated to 468,300 birds (95 % CI 430,700–505,900) or around 342,000 breeding pairs, distributed within 19 colonies. This represents an overall reduction of 13 % since the mid-/late 1980s. In the same period, five colonies went extinct. Large and apparently stable colonies in Qaanaaq (Northwest Greenland) account for more than half the population (68 %), but most other colonies declined heavily, with up to 6 % p.a. in the most critical areas. So far, nothing indicates that food is a limiting factor in Greenland during the breeding season, although rather few colonies have been studied in details. In contrast, illegal hunting and disturbances during the breeding season are still a problem in Greenland, despite more restrictive hunting regulations, and may explain much of the continued population decline. In addition, recent studies from Svalbard indicate that a large-scale deterioration of the marine environment in the North Atlantic, due to oceanographic changes, may impact recruitment to some of the Greenland colonies. Murre colonies in southern Upernavik, Disko Bay, South Greenland and East Greenland are in urgent need of additional conservation initiatives to avoid further declines and local extinctions.  相似文献   

14.
Pteropodidae possess unique muscles in the uropatagium called Musculus uropatagialis and M. depressor ossis styliformis. The homology of these muscles is important for the phylogenetic analysis of bats because the wing membrane is a characteristic feature for them. Here, I discuss the homology of M. uropatagialis and M. depressor ossis styliformis in Rousettus leschenaultii by tracing their innervations. I found that the dominant nerve for the M. uropatagialis contains the components of the sciatic nerve associated with the dominant nerve of the flexor muscles of the thigh. This result shows that M. uropatagialis is homologous to the flexor muscles of the thigh. The dominant nerve of M. depressor ossis styliformis is the lateral plantar nerve derived from the tibial nerve. Thus, this innervation pattern proposes the hypothesis that M. depressor ossis styliformis is homologous to one of the muscles of the foot sole.  相似文献   

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The origin of photosynthesis research in Greece can be traced to the early 1960s, and the first dedicated laboratory was established by George Akoyunoglou in the Nuclear Reseach Center (now National Center for Scientific Research) Demokritos, in Athens. More photosynthesis groups subsequently emerged, in Demokritos and in the universities. Research in Greece benefited greatly from the links of Greek scientists with laboratories and personalities, primarily in the USA and western Europe. The local research output is a proportional part of global research and, more or less, in tune with the shifting priorities of the latter. The list of references provided includes only a sample of publications: it is not inclusive. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

18.
19.
We present here a Tribute to Klaus Apel (1942–2017), a photosynthesis pioneer—an authority on plant molecular genetics—in five parts. The first section is a prologue. The second section deals with a chronological discussion of Apel’s research life, prepared by the editor Govindjee; it is based on a website article at the Boyce Thompson Institute (BTI) by Patricia Waldron (https://btiscience.org/explore-bti/news/post/bti-says-goodbye-klaus-apel/), as approved for use here by Keith C. Hannon and David Stern of BTI. The third section, which focuses on Apel’s pioneering work on singlet oxygen-mediated EXECUTER-dependent signaling in plants, is written by two of us (J-DR and CK). The fourth section includes three selected reminiscences, one from BTI and two from ETH (Eidgenössische Technische Hochschule). This tribute ends with section five, which is a very brief presentation of Klaus Apel’s personal life, by Wiebke Apel.  相似文献   

20.
The ‘third pole’ of the world is a fitting metaphor for the Himalayan–Tibetan Plateau, in allusion to its vast frozen terrain, rivalling the Arctic and Antarctic, at high altitude but low latitude. Living Tibetan and arctic mammals share adaptations to freezing temperatures such as long and thick winter fur in arctic muskox and Tibetan yak, and for carnivorans, a more predatory niche. Here, we report, to our knowledge, the first evolutionary link between an Early Pliocene (3.60–5.08 Myr ago) fox, Vulpes qiuzhudingi new species, from the Himalaya (Zanda Basin) and Kunlun Mountain (Kunlun Pass Basin) and the modern arctic fox Vulpes lagopus in the polar region. A highly hypercarnivorous dentition of the new fox bears a striking resemblance to that of V. lagopus and substantially predates the previous oldest records of the arctic fox by 3–4 Myr. The low latitude, high-altitude Tibetan Plateau is separated from the nearest modern arctic fox geographical range by at least 2000 km. The apparent connection between an ancestral high-elevation species and its modern polar descendant is consistent with our ‘Out-of-Tibet’ hypothesis postulating that high-altitude Tibet was a training ground for cold-environment adaptations well before the start of the Ice Age.  相似文献   

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