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Sub-Antarctic Marion Island has had a permanent research station for 50 years and the islands Wandering Albatrosses have been intensively studied for 20 years. The reactions of breeding birds to approaches by a human on foot were recorded. Three response variables were calculated: intensity of vocal reaction (IVR), intensity of non-vocal reaction (INR) and overall response index (ORI). At 5 m from the nest, twice as many birds stood and/or vocalised as at 15 m. Nearest neighbour distance, age and gender did not explain individual variability of responses. Study colony birds had higher IVR scores than non-study colony birds; birds at colonies closest to the station had the highest ORI scores. A better breeding record was associated with lower IVR and ORI scores, but a causative relationship remains to be demonstrated. A minimum viewing distance of 25 m is recommended for breeding Wandering Albatrosses.
Marienne S. de VilliersEmail: Fax: +27-21-6503434
John CooperEmail:
Peter G. RyanEmail:
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Semi-automated, Membrane-Based Protocol for DNA Isolation from Plants   总被引:1,自引:0,他引:1  
Many plant species are considered difficult for DNA isolation due to their high concentrations of secondary metabolites such as polysaccharides and polyphenols. Several protocols have been developed to overcome this problem, but they are typically time-consuming, not scalable for high throughput and not compatible with automation. Although a variety of commercial kits are available for plant DNA isolation, their cost is high and these kits usually have limited taxonomic applicability. In a previous study we developed an inexpensive automation-friendly protocol for DNA extraction from animal tissues. Here we demonstrate that a similar protocol allows DNA isolation from plants.
Natalia V. IvanovaEmail:
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The recent contribution by Jarmila Kukalová-Peck on Hennigian phylogenetics and hexapod limb evolution is critically evaluated.
Michael S. Engel (Corresponding author)Email:
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7.
A key point in the analysis of dynamical models of biological systems is to handle systems of relatively high dimensions. In the present paper we propose a method to hierarchically organize a certain type of piecewise affine (PWA) differential systems. This specific class of systems has been extensively studied for the past few years, as it provides a good framework to model gene regulatory networks. The method, shown on several examples, allows a qualitative analysis of the asymptotic behavior of a PWA system, decomposing it into several smaller subsystems. This technique, based on the well-known strongly connected components decomposition, is not new. However, its adaptation to the non-smooth PWA differential equations turns out to be quite relevant because of the strong discrete structure underlying these equations. Its biological relevance is shown on a 7-dimensional PWA system modeling the gene network responsible for the carbon starvation response in Escherichia coli.
Laurent Tournier (Corresponding author)Email:
Jean-Luc GouzéEmail:
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8.
Gridcast is an R&D project investigating grid ideas and technologies in the broadcasting technical infrastructure. In this paper I discuss the business and technical issues in building infrastructures to support broadcasters and outline the structure of the Gridcast grid-based service oriented architecture for broadcasting playout support.
Terry HarmerEmail:
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Pervasive Grid adoption is predicated on the availability of widely deployed usable software and a user community willing to use it. Currently, widespread adoption of Grids, even within technically sophisticated communities, is limited, and determining and eliminating these barriers to adoption are essential in order for Grids to becoming widely capitalized. Through a series of face-to-face interviews conducted during the summer of 2004, we have identified issues relating to job submission, file transfer, usability, and systems management that must be resolved in order to improve the usability of Grid infrastructures. The background to these issues and some possible solutions are described in this paper.
Jennifer M. SchopfEmail:
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Jablonka and Lamb's claim that evolutionary biology is undergoing a ‘revolution’ is queried. But the very concept of revolutionary change has uncertain application to a field organized in the manner of contemporary biology. The explanatory primacy of sequence properties is also discussed.
Peter Godfrey-SmithEmail:
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Methanogens growing on C-1 substrates synthesize 2-carbon acetyl groups in the form of acetyl-CoA for carbon assimilation using the multienzyme complex acetyl-CoA decarbonylase/synthase (ACDS) which contains five different subunits encoded within an operon. In species growing on acetate ACDS also functions to cleave the acetate C-C bond for energy production by methanogenesis. A number of species of Methanosarcina that are capable of growth on either C-1 compounds or acetate contain two separate ACDS operons, and questions have been raised about whether or not these operons play separate roles in acetate synthesis and cleavage. Methanosarcina thermophila genomic DNA was analyzed for the presence of two ACDS operons by PCR amplifications with different primer pairs, restriction enzyme analyses, DNA sequencing and Southern blot analyses. A single ACDS operon was identified and characterized, with no evidence for more than one. MALDI mass spectrometric analyses were carried out on ACDS preparations from methanol- and acetate-grown cells. Peptide fragmentation patterns showed that the same ACDS subunits were present regardless of growth conditions. The evidence indicates that a single form of ACDS is used both for acetate cleavage during growth on acetate and for acetate synthesis during growth on C-1 substrates. Electronic Supplementary Material  Supplementary material is available for this article at
David A. Grahame (Corresponding author)Email:
Edward DeMoll (Corresponding author)Email:
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Conservation conflicts are often difficult to resolve due to a combination of poorly defined property rights, inadequate funding, high transaction costs, and contrasting value systems among stakeholders. This paper explores these barriers to collaboration in the context of the emerging deer crisis in the Scottish Highlands, where deer numbers are now higher than at any time in recorded history. In particular we explore the potential role of recreational hunting in the government’s strategy to contain rising deer numbers from the landowners’ perspective. Using both qualitative and quantitative analysis we find that hunting traditions and personal preferences, reinforced by antipathy to conservationists and their perceptions of land stewardship, are the major barriers to shooting more deer for conservation objectives. We conclude that an expansion of commercial hunting opportunities is the best practical approach to resolving the current conflict over deer, but conservationists and landowners must work together to create a more positive context for hunter-conservation initiatives and activities.
Douglas C. MacMillanEmail:
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Problems with studies, claims, and assumptions that have been made about the causes of fires in Indonesia's tropical moist forests are identified, and the kinds of concepts, methods, prioritizing, and data needed to resolve the problems are discussed. Separate sections are devoted to studying ignitions, studying fire susceptibility and fire behavior, and using the goal of causal explanation to guide interdisciplinary research.
Andrew P. VaydaEmail:
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Recent advances in hardware and software virtualization offer unprecedented management capabilities for the mapping of virtual resources to physical resources. It is highly desirable to further create a “service hosting abstraction” that allows application owners to focus on service level objectives (SLOs) for their applications. This calls for a resource management solution that achieves the SLOs for many applications in response to changing data center conditions and hides the complexity from both application owners and data center operators. In this paper, we describe an automated capacity and workload management system that integrates multiple resource controllers at three different scopes and time scales. Simulation and experimental results confirm that such an integrated solution ensures efficient and effective use of data center resources while reducing service level violations for high priority applications.
Ludmila CherkasovaEmail:
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   Soil conservation is widely regarded a critical component of sustainable livelihood strategies for the hillsides of Honduras. However, neoliberal polices have reduced economic incentives for agricultural intensification. Recent studies indicate off-farm work opportunities address poverty in a way conservation and development efforts do not. Yet off-farm work may discourage poor farmers from practicing soil conservation. A middle ground is needed. This study indicates micro-credit can substitute for off-farm work and encourage soil conservation practice. Many regions throughout Honduras have had extensive contact with soil conservation programs and would benefit more from credit services than redundant technological extension.
Christina H. GladwinEmail:
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18.
Syndromic surveillance uses new ways of gathering data to identify possible disease outbreaks. Because syndromic surveillance can be implemented to detect patterns before diseases are even identified, it poses novel problems for informed consent, patient privacy and confidentiality, and risks of stigmatization. This paper analyzes these ethical issues from the viewpoint of the patient as victim and vector. It concludes by pointing out that the new International Health Regulations fail to take full account of the ethical challenges raised by syndromic surveillance.
Leslie P. FrancisEmail:
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Best practices for improved governance of coral reef marine protected areas   总被引:2,自引:0,他引:2  
Coral reef marine protected areas (MPA) are widely distributed around the globe for social and ecological reasons. Relatively few of these MPAs are well managed. This review examines the governance of coral reef MPAs and the means to improve coral reef MPA management. It highlights common governance challenges, such as confused goals, conflict, and unrealistic attempts to scale up beyond institutional capacity. Recommendations, based on field experience and empirical evidence from around the world, are made for best practices at various stages of MPA implementation.
A. T. WhiteEmail:
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In researching the biomedically-engineered drug Neulasta (filgrastim), a breast cancer patient becomes aware of the extent to which knowledge about the development and marketing of drugs influences her decisions with regard to treatment. Time spent on understanding the commercial interests of insurers and pharmaceutical companies initially thwarts but ultimately aids the healing process. This first-person narrative calls for physicians to recognize that the alignment of commercial interests transgresses the patient’s humanity.
Jane E. SchultzEmail:
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