Eradications of invasive alien species in Europe: a review

Eradication of alien species is a key conservation tool to mitigate the impacts caused by biologic invasions. The aim of the present paper is to review the eradications successfully completed in Europe and to discuss the main limits to a wider application of this management option in the region. On the basis of the available literature – including conference proceedings, national reports to the Bern Convention, etc. – a total of 37 eradication programmes have been recorded. Thirty-three eradications were carried out on islands and four on the mainland. The rat (Rattus spp.) has been the most common target (n = 25, 67%), followed by the rabbit (n = 4). In many cases, these eradications determined a significant recovery of native biodiversity. Differently to other regions of the world, no eradications of alien invertebrates and marine organisms have been recorded; regarding invasive alien plants, it appears that only some very localized removals have been completed so far in Europe. The limited number of eradications carried out in Europe so far is probably due to the limited awareness of the public and the decision makers, the inadequacy of the legal framework, and the scarcity of resources. Synthetic guidelines for improving the ability of European states to respond to aliens incursions are presented. This revised version was published online in July 2006 with corrections to the Cover Date.     

Adenomatous polyposis coli influences micronuclei induction by PhIP and acrylamide in mouse erythrocytes

Micronucleus (MN) induction in erythrocytes of multiple intestinal neoplasia (Min) mice with heterozygous Apc mutation was measured after s.c. injections of acrylamide, glycidamide, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) and colchicine, and compared with wild-type (wt) mice. Since Apc influences microtubule dynamics, we wanted to test whether Min-mice were more sensitive to the production of MN than wild-type mice. We also examined the effect of pre-treatment with cytosine β-D-arabinofuranoside (Ara C) and hydroxyurea, which inhibit ligation of DNA strand breaks in the repair of DNA adducts. All compounds induced a significant increase in MN in both strains of mice with the following potencies: acrylamide < glycidamide < PhIP. No difference in the induction of MN was seen between Min-mice and wt-mice exposed to acrylamide, glycidamide or colchicine without pre-treatment. However, in Min-mice, PhIP treatment induced much less MN than in wt-mice, with about four- and six-fold increase in MN in Min-mice and wt-mice, respectively. A reduced ability to repair PhIP adducts may be the reason for the lower induction of MN in Min-mice. Treatment with Ara C and hydroxyurea, to increase sensitivity, gave more than a four-fold increase in MN, but strongly reduced proliferation. Pre-treatment with Ara C and hydroxyurea made the Min-mice slightly more sensitive to MN induction by glycidamide compared to wt-mice. We conclude that Min-mice are less sensitive than wt-mice to MN induction by PhIP that forms bulky DNA adducts, while Min-mice and wt-mice are equally sensitive to MN induction by acrylamide and glycidamide that form DNA base adducts.     

Study of the Impact of Replacement Granularity and Associated Strategies on Video Caching

Partial caching of large media objects such as video files has been proposed recently as the caching of entire objects can easily exhaust the storage resources of a proxy server. In this paper the idea of segmenting video files into chunks and applying replacement decisions at the chunk level rather than on entire videos is examined. It is shown that a higher byte hit ratio (BHR) can be achieved by appropriately adjusting the replacement granularity. The price paid for the improved BHR performance is that the replacement algorithm takes a longer time to converge to the steady state BHR. For the segmentation of video into chunks two methods are presented. The Fixed Chunk Size segmentation scheme that is rather simple and reveals the basic trade-off between byte hit ratio (BHR) and responsiveness to changes of popularity; the Variable Chunk Size segmentation scheme that uses the request frequencies to dynamically adjust the size of the chunk and is shown to be capable of combining a small response time with high BHR. Moreover, a variation of the fixed chunk size segmentation scheme is presented, which is shown to improve its performance by switching between different chunk sizes. Video segmentation is also considered as a mechanism to provide for caching differentiation based on access costs. By employing access cost dependent chunk sizes an overall access cost reduction is demonstrated.     

Stability and specificity of heterodimer formation for the coiled-coil neck regions of the motor proteins Kif3A and Kif3B: the role of unstructured oppositely charged regions.

We investigated the folding, stability, and specificity of dimerization of the neck regions of the kinesin-like proteins Kif3A (residues 356-416) and Kif3B (residues 351-411). We showed that the complementary charged regions found in the hinge regions (which directly follow the neck regions) of these proteins do not adopt any secondary structure in solution. We then explored the ability of the complementary charged regions to specify heterodimer formation for the neck region coiled-coils found in Kif3A and Kif3B. Redox experiments demonstrated that oppositely charged regions specified the formation of a heterodimeric coiled-coil. Denaturation studies with urea demonstrated that the negatively charged region of Kif3A dramatically destabilized its neck coiled-coil (urea1/2 value of 3.9 m compared with 6.7 m for the coiled-coil alone). By comparison, the placement of a positively charged region C-terminal to the neck coiled-coil of Kif3B had little effect on stability (urea1/2 value of 8.2 m compared with 8.8 m for the coiled-coil alone). The pairing of complementary charged regions leads to specific heterodimer formation where the stability of the heterodimeric neck coiled-coil with charged regions had similar stability (urea1/2 value of 7.8 m) to the most stable homodimer (Kif3B) with charged regions (urea1/2 value of 8.0 m) and dramatically more stable than the Kif3A homodimer with charged regions (urea1/2, value of 3.9 m). The heterodimeric coiled-coil with charged extensions has essentially the same stability as the heterodimeric coiled-coil on its own (urea1/2 values of 7.8 and 8.1 m, respectively) suggesting that specificity of heterodimerization is driven by non-specific attraction of the oppositely unstructured charged regions without affecting stability of the heterodimeric coiled-coil.     

Fauna habitat modelling and mapping: A review and case study in the Lower Hunter Central Coast region of NSW

Abstract Habitat models are now broadly used in conservation planning on public lands. If implemented correctly, habitat modelling is a transparent and repeatable technique for describing and mapping biodiversity values, and its application in peri‐urban and agricultural landscape planning is likely to expand rapidly. Conservation planning in such landscapes must be robust to the scrutiny that arises when biodiversity constraints are placed on developers and private landholders. A standardized modelling and model evaluation method based on widely accepted techniques will improve the robustness of conservation plans. We review current habitat modelling and model evaluation methods and provide a habitat modelling case study in the New South Wales central coast region that we hope will serve as a methodological template for conservation planners. We make recommendations on modelling methods that are appropriate when presence‐absence and presence‐only survey data are available and provide methodological details and a website with data and training material for modellers. Our aim is to provide practical guidelines that preserve methodological rigour and result in defendable habitat models and maps. The case study was undertaken in a rapidly developing area with substantial biodiversity values under urbanization pressure. Habitat maps for seven priority fauna species were developed using logistic regression models of species‐habitat relationships and a bootstrapping methodology was used to evaluate model predictions. The modelled species were the koala, tiger quoll, squirrel glider, yellow‐bellied glider, masked owl, powerful owl and sooty owl. Models ranked sites adequately in terms of habitat suitability and provided predictions of sufficient reliability for the purpose of identifying preliminary conservation priority areas. However, they are subject to multiple uncertainties and should not be viewed as a completely accurate representation of the distribution of species habitat. We recommend the use of model prediction in an adaptive framework whereby models are iteratively updated and refined as new data become available.     

Design considerations for array CGH to oligonucleotide arrays.

BACKGROUND: Representational oligonucleotide microarray analysis has been developed for detection of single nucleotide polymorphisms and/or for genome copy number changes. In this process, the intensity of hybridization to oligonucleotides arrays is increased by hybridizing a polymerase chain reaction (PCR)-amplified representation of reduced genomic complexity. However, hybridization to some oligonucleotides is not sufficiently high to allow precise analysis of that portion of the genome. METHODS: In an effort to identify aspects of oligonucleotide hybridization affecting signal intensity, we explored the importance of the PCR product strand to which each oligonucleotide is homologous and the sequence of the array oligonucleotides. We accomplished this by hybridizing multiple PCR-amplified products to oligonucleotide arrays carrying two sense and two antisense 50-mer oligonucleotides for each PCR amplicon. RESULTS: In some cases, hybridization intensity depended more strongly on the PCR amplicon strand (i.e., sense vs. antisense) than on the detection oligonucleotide sequence. In other cases, the oligonucleotide sequence seemed to dominate. CONCLUSION: Oligonucleotide arrays for analysis of DNA copy number or for single nucleotide polymorphism content should be designed to carry probes to sense and antisense strands of each PCR amplicon to ensure sufficient hybridization and signal intensity.     

Dutch guidelines for interventional cardiology: institutional and operator competence and requirements for training

Interventional cardiology is an expanding field within cardiovascular medicine and today it is generally accepted that cardiologists require specific training, knowledge and skills. Hospitals where coronary interventions are performed must be properly equipped and able to provide specialised care. Percutaneous coronary interventions are frequently used for coronary revascularisation. The public should have confidence in the uniformity of high quality care. Therefore, such quality of care should be maintained by certification of the individual operators, general guidelines for institutional requirements and formal audits. The Netherlands Society of Cardiology (NVVC) will be implementing a new registration system for cardiologists with a subspecialisation that will include registration for interventional cardiology. The NVVC asked the Working Group of Interventional Cardiology (WIC) to update the 1994 Dutch guidelines on operator and institutional competence, and requirements for training in interventional cardiology in order to incorporate them into the official directives. The present guidelines represent the expert opinion of the Dutch interventional cardiology community and are in accordance with international regulations.After two rounds of discussion, the NVVC approved the guidelines in November 2004 during the autumn meeting.     

RNA isolation from yeast using silica matrices.

RNA isolation from yeast is complicated by the need to initially break the cell wall. While this can be accomplished by glass bead disruption or enzyme treatment, these approaches result in DNA contamination and/or the need for incubation periods. We have developed a protocol for the isolation of RNA samples from yeast that minimizes degradation by RNases and incorporates two purification steps: acid phenol extraction and binding to a silica matrix. The procedure requires no precipitation steps, facilitating automation, and can be completed in less than 90 min. The RNA quality is ideal for microarray analysis.