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1.
《Plains anthropologist》2013,58(63):46-54
Abstract

In the field of archaeology there has been an increasing concern for the standardization of terminology, units of measurement, and theoretical concepts. At the same time there has been a tremendous influx of new ideas, challenges to established concepts and theories, and a rethinking of the place of archaeology in the social sciences. Much of this re-evaluation has come about as a result of new insights into the nature of human society and, perhaps more importantly, a general opening up of the field in the sense that ideas, theories, and techniques developed in the social, biological, physical, and mathematical sciences are being introduced and tested for their application in the solution of anthropological and archaeological questions. One area which has become increasingly important as a source of concepts and theory is the field of biological ecology. This discussion considers two of these ecological concepts (seasonality, econiche) and proposes a sequence of socio-ecological units (individual, group, population, society, eco-community, eco-system) which it is believed are useful in the study of prehistoric social and settlement systems.  相似文献   

2.
ABSTRACT

Introduction: Protein microarray is a powerful tool for both biological study and clinical research. The most useful features of protein microarrays are their miniaturized size (low reagent and sample consumption), high sensitivity and their capability for parallel/high-throughput analysis. The major focus of this review is functional proteome microarray.

Areas covered: For proteome microarray, this review will discuss some recently constructed proteome microarrays and new concepts that have been used for constructing proteome microarrays and data interpretation in past few years, such as PAGES, M-NAPPA strategy, VirD technology, and the first protein microarray database. this review will summarize recent proteomic scale applications and address the limitations and future directions of proteome microarray technology.

Expert opinion: Proteome microarray is a powerful tool for basic biological and clinical research. It is expected to see improvements in the currently used proteome microarrays and the construction of more proteome microarrays for other species by using traditional strategies or novel concepts. It is anticipated that the maximum number of features on a single microarray and the number of possible applications will be increased, and the information that can be obtained from proteome microarray experiments will more in-depth in the future.  相似文献   

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4.
The focus on place rather than space provides geography with a powerful raison d’être. As in human geography, the functional role of place is integral to the understanding of evolution, persistence and extinction of biotic taxa. This paper re‐examines concepts and biogeographical evidence from a geographical rather than ecological or evolutionary perspective. Functional areography provides convincing arguments for a postmodern deconstruction of major principles of the dynamic Equilibrium Theory of Island Biogeography (ETIB). Endemic oceanic island taxa are functionally insular as a result of long‐term island stability, confinement, isolation, and protection from continental invasion and disturbance. Most continental taxa persist in different, more complex and open spatial systems; their geographical place is therefore fundamentally distinct from the functional insularity of oceanic island taxa. This creates an insular‐continental polarity in biogeography that is currently not reflected in conservation theory. The focus on the biogeographical place leads to the development of the eigenplace concept defined as the functional spatial complex of existence. The application of still popular ETIB concepts in conservation biology is discouraged. The author calls for the integration of functional areography into modern conservation science.  相似文献   

5.
ABSTRACT

Background: Tropical mountain ecosystems of the Northern Andes have long fascinated researchers because of the unique conditions associated with cold climates in equatorial latitudes. More than six decades have elapsed since the beginning of systematic ecological research in the Venezuelan páramos, making them one of the best-studied tropical alpine regions in the world.

Aims: We review the conceptual development and state of the art of ecological research in the Venezuelan páramos, with emphasis on environmental and plant ecology research, presenting a general framework for the studies included in this special issue.

Methods: We provide a historical sketch of the periods that have marked ecological studies in the Venezuelan páramos. Then, we synthesise research on environmental drivers, plant population and community ecology, ecosystem functioning, the response of the páramo to climate change and human disturbance; we finally consider agroecology and conservation.

Results and conclusions: This review demonstrates the significant contributions made to alpine ecology in key areas such as biodiversity/ecosystem function changes during succession, nutrient cycling, species interactions and socio-ecological research. We indicate the need to develop a more integrated view of the links between evolutionary processes, functional diversity, community dynamics and ecosystem services both in natural and human-impacted areas.  相似文献   

6.
A general education biology course entitled ‘Biotechnology Transforms Our World’ has been developed to illustrate biological concepts with advances from biotechnology. The contributions of molecular biology to understanding human genetics, evolution, plant and animal (including human) biology and ecology are illustrated with specific case studies. Journal of Industrial Microbiology & Biotechnology (2000) 24, 308–309. Received 02 April 1999/ Accepted in revised form 11 November 1999  相似文献   

7.
BackgroundIn-cell NMR is a powerful technique to investigate proteins in living human cells at atomic resolution. Ideally, when studying functional processes involving protein–protein interactions by NMR, only one partner should be isotopically labeled. Here we show that constitutive and transient protein expression can be combined with protein silencing to obtain selective protein labeling in human cells.MethodsWe established a human cell line stably overexpressing the copper binding protein HAH1. A second protein (human superoxide dismutase 1, SOD1) was overexpressed by transient transfection and isotopically labeled. A silencing vector containing shRNA sequences against the HAH1 gene was used to decrease the rate of HAH1 synthesis during the expression of SOD1. The levels of HAH1 mRNA and protein were measured as a function of time following transfection by RT-PCR and Western Blot, and the final cell samples were analyzed by in-cell NMR.ResultsSOD1 was ectopically expressed and labeled in a time window during which HAH1 biosynthesis was strongly decreased by shRNA, thus preventing its labeling. In-cell NMR spectra confirmed that, while both proteins were present, only SOD1 was selectively labeled and could be detected by 1H–15N heteronuclear NMR.Conclusions and general significanceWe showed that controlling protein expression by specifically silencing a stably expressed protein is a useful strategy to obtain selective isotope labeling of only one protein. This approach relies on established techniques thus permitting the investigation of protein–protein interactions by NMR in human cells.  相似文献   

8.

This paper is concerned with the task of developing a 'knowledgeable society' for biotechnology. This is hindered by the fact that the scientific and commercial communities often engage in separate discourses from that which engages the general public. Different concepts of knowledge ('knowing') and learning underpin preoccupations and concerns in these three spheres, and different logics and assumptions about knowledge often apply. The paper begins by highlighting the key issues that exercise people in the public domain, and in relation to science and industry. It then applies concepts of knowledge, communication and learning to show how people in these domains construct issues differently. Finally, it makes some predictions and suggestions for how a more knowledgeable society may evolve.  相似文献   

9.
ABSTRACT

Individual based models (IBMs) are up-to-date tools both in research and educational areas. Here we introduce an IBM built on NetLogo platform that simulates a top-down trophic cascade controlled by the pressure exerted by two model predators (web-building spiders and ground runner spiders) on a model pest (the olive fruit fly) within a hypothetical agricultural landscape (the olive crop). EcoPred is an IBM that aims to be an educational tool that can help teachers to explain concepts related to ecology in a modern, enjoyable and comprehensive way. EcoPred reflects the changes on a fly population within a simulated olive crop according to (1) the mortality rate caused by the predation of two spider species and energy loss, (2) the energy gain by feeding on flowers and (3) the reproduction rate in olive trees. The model was tested with 26 students achieving very good results in terms of acceptance and interest on the learning method. EcoPred can be used for educational purposes with 16 year old students and older to explain ecological concepts such as trophic level, species interactions, limiting factor and biological control in an interactive way simultaneously introducing students to biology oriented programming languages.  相似文献   

10.
【目的】为探究长期连作土壤细菌群落结构和分子生态网络与土壤环境演化的关联性。【方法】本研究利用16S rRNA基因高通量测序技术,解析了湖南省浏阳市两块连作十二年农田(表现连作障碍的GD和健康的YA)土壤微生物群落组成结构和分子生态网络拓扑性质与土壤理化性质的关系。【结果】GD土壤总氮和有效磷含量显著高于YA,而土壤硝态氮和速效钾含量显著低于YA(P<0.05)。GD土壤细菌群落多样性高于YA,两地土壤细菌群落结构存在显著差异(P<0.01),且与土壤pH和有效磷含量相关。进一步分析表明,GD土壤细菌群落之间比YA具有更复杂的生态网络,主要体现在能量代谢、碳循环和氮循环功能模块。【结论】综上所述,连作会引起土壤细菌群落多样性、组成结构和生态网络变化,这可能与土壤理化性质恶化、土壤肥力下降密切相关,进而影响作物生长发育。  相似文献   

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Ecological risk actually refers to two separate things. First, risk to the environment as a result of human activity. Contaminated sites are an example. Second, risk to the biota—flora, fauna, and people—as a result of environmental hazards. Geophysical risk arising from natural hazards is an example. Risk is a combination of likelihoods and consequences. This article examines methods used to quantify the consequences. At the general level, such methods are linked to the methods used to quantify the likelihoods and thus to quantify the risks. It is possible to use the existing frameworks of risk management, health risk assessment, and ecological risk analysis to develop a risk management framework that is suitable for ecological risk assessment. The framework consists of the following steps:
  1. Determine concernsby using risk assessment techniques for various scenarios.

  2. Identify the consequences by systematically identifying hazards.

  3. Undertake calculations by using relevant models.

  4. Evaluate certainties, uncertainties, and probabilities involved in the calculations of the vulnerability and of the exposure.

  5. Compare with criteriato assess the need for further action.

  6. Determine and act on options to control, mitigate, and adapt to the risk.

  7. Communicatethe results to those who need to know.

  相似文献   

13.
The combination of microautoradiography and fluorescence in situ hybridization (MAR-FISH) is a powerful technique for tracking the incorporation of radiolabelled compounds by specific bacterial populations at a single cell resolution. It has been widely applied in aquatic microbial ecology as a tool to unveil key ecophysiological features, shedding light on relevant ecological issues such as bacterial biomass production, the role of different bacterioplankton groups in the global carbon and sulphur cycle, and, at the same time, providing insights into the life styles and niche differentiation of cosmopolitan members of the aquatic microbial communities. Despite its great potential, its application has remained restricted to a few laboratories around the world, in part due to its reputation as a “difficult technique”. Therefore, the objective of this minireview is to highlight the impact of MAR-FISH application on aquatic microbial ecology, and also to provide basic concepts, as well as practical tips, for processing MAR-FISH preparations, thus aiming to contribute to a more widespread application of this powerful method.  相似文献   

14.
After defining ‘ecology’, outlining the basic categories of ecological research and listing examples of modern ecological investigations, this introductory paper focusses on basic considerations; it is, in essence, a programmatic contribution. Research details on the ecology of the North Sea are the subject of the following papers. Theproblems of ecological North Sea research are formidable. Hydrological and biological fluctuations and variabilities are pronounced. Exchange patterns with the Atlantic are complex, and the inputs of rivers and rain defy exact measurement and prediction. Season, weather, climate—and as yet insufficiently known and controlled human-caused impacts—further complicate the situation. All this results in an unusually high degree of uncertainty. New questions and problems arise before the old ones can be answered or solved. Nevertheless, ecological North Sea research has achieved manysuccesses. The North Sea is the most intensively investigated sea area on our planet. Generations of zoologists, botanists and hydrographers — and more recently microbiologists, meteorologists, climatologists, chemists, pathologists and toxicologists — have produced an impressive body of knowledge. Slowly we are beginning to understand the forces that govern energy budgets and balances, material fluxes, and the factors that control and direct ecosystem dynamics. Essential driving forces of ecosystem dynamics result from microbial, especially bacterial, activities. Ecological modelling has paved the way for new theories and insights, and holds promise for progress towards a predictive ecology.Failures and shortcomings include insufficient long-term research, inadequately designed experiments, and misconceptions in environmental protection. Net changes in ecological processes of an heterogeneous and intensely varying environment such as the North Sea can only be comprehended adequately against the background of sustained measurements over decades.Future needs include: more long-term research; and new patterns of management, institutional organization and financial support. Essential breakthroughs in field-work demand more teamwork, in-situ experimentation and surveys from space. Studies on the health status of organisms and ecosystems should receive more attention. Finally, there is need for changes in human behaviour: we must use our insight and willpower to meet the deadly consequences of our self-made scientific-technological evolution by an equally self-made ethical evolution aimed at achieving a re-harmonization with nature.  相似文献   

15.
Vicariance and isolation leading to speciation of reptiles on islands is well exemplified in a number of taxa in the Caribbean. The St. Lucia whiptail (Cnemidophorus vanzoi), considered a single species, is found on two small islets (Maria Major and Maria Minor) off the main island of St. Lucia. From lizards collected from both localities, we gathered morphological measurements and analysed the genetic divergence between populations, using a molecular survey of ∼ ∼2800 mtDNA base pairs and 8 microsatellites. There are significant differences in body size and general form and fixed but small mtDNA differences between island populations. Microsatellites reveal low diversity within populations but very high differentiation between islands with non-overlapping allele size ranges at all except one microsatellite and two loci exhibiting single-base polymorphism, fixed between islands. Based on these results, we examine published criteria to determine whether the studied island forms could be considered true species. According to the phylogenetic species concept and Moritz’s evolutionary significant unit (ESU) criteria, the two lizard populations can be considered separate entities. Crandall et al.’s (2000, Trends Ecol. Evol., 15, 290–295) broader categorization of population distinctiveness, based on concepts of ecological and genetic exchangeability, produces conflicting results depending on the interpretation of the observed ecological data. Following Fraser and Bernatchez’s (2001, Mol. Ecol., 10, 2741–2752) framework for management decisions when ecological data are not sufficient we propose that the lizard populations on the Maria islands are on differing evolutionary trajectories and thus at the species boundary. The populations are of high priority to conservation, thus meriting separate management.  相似文献   

16.
Abstract

Resistance towards herbivory is expected to influence the competitive ability and ecological success of the resistant plant, but it is unclear how this general knowledge should be incorporated into long-term ecological predictions of plant community dynamics. In order to answer such questions, the long-term ecological effects of density, competition, herbivory and their compound interactions were investigated in a model system of a transgenic herbivore-resistant Arabidopsis thaliana genotype and the isogenic herbivore-sensitive A. thaliana genotype. It was concluded that herbivory had a significant effect on the fecundity of the susceptible genotype at high plant density. The most likely long-term scenario was that the susceptible genotype outcompeted the resistant genotype. But it was also shown that herbivory could down-regulate the equilibrium density of the susceptible genotype and, when the two genotypes were coexisting, up-regulate the equilibrium density of the resistant genotype.  相似文献   

17.
18.
Highlights? Protein and position-specific statistical potentials are more powerful ? Evolutionary information greatly boost performance of statistical potentials ? Observed probability is critical to energy potentials, in addition to reference state ? Observed probability can be estimated better using context-specific information  相似文献   

19.
Abstract

Taxonomic concepts (sensu Berendsohn) embody the underlying meanings of scientific names as stated in a particular publication, thus offering a new way to resolve semantic ambiguities that result from multiple revisions of a taxonomic name. This paper presents a comprehensive and powerful language for representing the relationships among taxonomic concepts. The language features terms and symbols for concept relationships within a single taxonomic hierarchy, or between two related but independently published hierarchies. Taxonomic concepts pertaining to a single hierarchy are characterised by parent/child relationships, whereas those pertaining to two independent hierarchies may have the following basic relationships: congruence, inclusion (non‐symmetrical, relative to the side of comparison), overlap, and exclusion. The relationships are asserted by specialists who have the option to add or subtract concepts on one or both sides of a relationship equation in order to reconcile differences between non‐congruent taxonomic perspectives. The terms ‘and’, ‘or’ and ‘not’ are available, respectively, to connect multiple simultaneously or alternatively valid relationship assessments, or to explicitly negate the validity of a relationship. The language also permits the decomposition of a relationship according to the intensional (property referencing) and ostensive (member pointing) aspects of the compared taxonomic concepts. Adopting the concept relationship language will facilitate a more precise documentation of similarities and differences in multiple succeeding taxonomic perspectives, thereby preparing the stage for an ontology‐based integration of taxonomic and related biological information.  相似文献   

20.
Understanding how and why rates of evolutionary diversification vary is a key issue in evolutionary biology, ecology, and biogeography. Evolutionary rates are the net result of interacting processes summarized under concepts such as adaptive radiation and evolutionary stasis. Here, we review the central concepts in the evolutionary diversification literature and synthesize these into a simple, general framework for studying rates of diversification and quantifying their underlying dynamics, which can be applied across clades and regions, and across spatial and temporal scales. Our framework describes the diversification rate (d) as a function of the abiotic environment (a), the biotic environment (b), and clade‐specific phenotypes or traits (c); thus, d ~ a,b,c. We refer to the four components (ad) and their interactions collectively as the “Evolutionary Arena.” We outline analytical approaches to this framework and present a case study on conifers, for which we parameterize the general model. We also discuss three conceptual examples: the Lupinus radiation in the Andes in the context of emerging ecological opportunity and fluctuating connectivity due to climatic oscillations; oceanic island radiations in the context of island formation and erosion; and biotically driven radiations of the Mediterranean orchid genus Ophrys. The results of the conifer case study are consistent with the long‐standing scenario that low competition and high rates of niche evolution promote diversification. The conceptual examples illustrate how using the synthetic Evolutionary Arena framework helps to identify and structure future directions for research on evolutionary radiations. In this way, the Evolutionary Arena framework promotes a more general understanding of variation in evolutionary rates by making quantitative results comparable between case studies, thereby allowing new syntheses of evolutionary and ecological processes to emerge.  相似文献   

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