Would species richness estimators change the observed species area relationship?

Copyright © 2008 Elsevier Masson SAS. All rights reserved.We evaluate whether the description of the species area relationship (SAR) can be improved by using richness estimates instead of observed richness values. To do this, we use three independent datasets gathered with standardized survey methods from the native laurisilva forest of the Azorean archipelago, encompassing different distributional extent and biological groups: soil epigean arthropods at eight forest fragments in Terceira Island, canopy arthropods inhabiting Juniperus brevifolia at 16 forest fragments of six different islands, and bryophytes of seven forest fragments from Terceira and Pico islands. Species richness values were estimated for each forest fragment using seven non-parametric estimators (ACE, ICE, Chao1, Chao2, Jackknife1, Jackknife2 and Bootstrap; five in the case of bryophytes). These estimates were fitted to classical log–log species–area curves and the intercept, slope and goodness of fit of these curves were compared with those obtained from the observed species richness values to determine if significant differences appear in these parameters. We hypothesized that the intercepts would be higher in the estimated data sets compared with the observed data, as estimated richness values are typically higher than observed values. We found partial support for the hypothesis – intercepts of the SAR obtained from estimated richness values were significantly higher in the case of epigean arthropods and bryophyte datasets. In contrast, the slope and goodness of fit obtained with estimated values were not significantly different from those obtained from observed species richness in all groups, although a few small differences appeared. We conclude that, although little is gained using these estimators if data come from standardized surveys, their estimations could be used to analyze macroecological relationships with non-standardized observed data, provided that survey incompleteness and/or unevenness are also taken into account

Azorean Bryophytes : a preliminary review of rarity patterns

Proceedings of the Symposium "Darwin's Mistake and what we are doing to correct it". Ponta Delgada, 19-22 September, 2009.Os briófitos podem ser tão raros e estar tão ameaçados como os demais organismos do planeta, apesar de o seu pequeno tamanho, cores discretas e difícil identificação no campo poderem mascarar o seu verdadeiro estatuto de conservação. De facto, é reconhecido que cerca de um quarto de todos os briófitos da Europa estão efectiva ou potencialmente ameaçados. O primeiro “Livro Vermelho dos Briófitos da Europa” foi produzido em 1995, amplamente baseado em listas vermelhas nacionais e no trabalho de uma vasta equipa de briólogos que avaliaram o estatuto de conservação para as espécies Europeias. A classificação de briófitos em listas vermelhas tem contribuído para aumentar a sensibilidade dos gestores para este grupo de organismos e alguns esforços têm sido desenvolvidos na Europa, para preservar locais tendo como característica o seu interesse briológico. Consequentemente, uma lista vermelha para os briófitos dos Açores pode auxiliar os gestores regionais a identificar espécies particularmente ameaçadas, tornando-se o primeiro passo para assegurar a sua protecção. Neste artigo usamos uma adaptação dos trabalhos de Deborah Rabinowitz (1981), que criou uma tipologia para desocultar e avaliar várias formas de raridade, utilizando três variáveis: Distribuição Geográfica, Abundância e Especificidade do Habitat. Todas as 480 espécies e subespécies dos Açores foram investigadas: 215 taxa não tinham informação suficiente para ser analisados (deficientes em dados), 121 não foram consideradas raros e 144 briófitos (1 antocerota, 56 hepáticas e 87 musgos) foram considerados raros pelo menos num dos parâmetros considerados. Os benefícios e limitações desta metodologia são brevemente discutidos. São propostas algumas sugestões práticas para melhorar a estratégia de conservação dos briófitos seleccionados.ABSTRACT: Bryophytes are not exempt of rarity and threat, although their small size, mute colours and difficult field identification may mask their true conservation status. Actually, it is known that a quarter of all European bryophytes are under actual or potential threat. The first Red Data Book for European Bryophytes was produced in 1995, largely based on national red lists and on the work of a vast team of bryologists who assessed the conservation status of each European species. The red listing of bryophytes has undoubtedly contributed to increase the awareness of planners to this group of organisms, and several efforts have been made, through Europe, to preserve sites based on their bryological interest. Accordingly, a specific Red List for the Azorean Bryophytes may help regional managers to identify particularly endangered species, thus allowing for the creation of measures to improve their preservation. In this paper we have used an adaptation of the works of Deborah Rabinowitz (1981), who created a typology to access different forms of rarity, using three variables: Geographical Distribution, Abundance and Habitat Specificity. All the 480 species and subspecies known to occur in the Azores were surveyed; of these, 215 species lacked sufficient data to be analyzed (data deficient), 121 were not considered rare and 144 (1 hornworts, 56 liverworts and 87 mosses) were considered rare, at least in one of the three parameters considered. The benefits and limitations of the methodology are briefly discussed. Several practical suggestions are proposed in order to enhance the conservation of selected bryophyte species

Propagating transverse waves in soft X-ray coronal jets

Aims. The theoretical model for magnetohydrodynamic (MHD) modes guided by a field-aligned plasma cylinder with a steady flow is adapted to interpret transverse waves observed in solar coronal hot jets, discovered with Hinode/XRT in terms of fast magnetoacoustic kink modes. Methods. Dispersion relations for linear magnetoacoustic perturbations of a plasma jet of constant cross-section surrounded by static magnetised plasma are used to determine the phase and group speeds of guided transverse waves and their relationship with the physical parameters of the jet and the background plasma. The structure of the perturbations in the macroscopic parameters of the plasma inside and outside the jet, and the phase relations between them are also established. Results. We obtained a convenient expansion for the long wave-length limit of the phase and group speeds and have shown that transverse waves observed in soft-X-ray solar coronal jets are adequately described in terms of fast magnetoacoustic kink modes by a magnetic cylinder model, which includes the effect of a steady flow. In the observationally determined range of parameters, the waves are not found to be subject to either the Kelvin-Helmholtz instability or the negative energy wave instability, and hence they are likely to be excited at the source of the jet

Well-being, work comfort and food security are better than maximizing production in the Amazon.

In the Amazon, slash and burn is the most common technique used by American-Indians, small farmers and even big ranches to transform forests into rural landscapes. The basis of food subsistence for diverse populations (rice, corn and bean), slash and burn is also a must for the plantation of cocoa, coffee, palms and pastures. The Amazonian rural landscape is currently dominated by pastures, occupying around 80 % of the deforested surface. Even if the nature of the plantation varies according to location, height, soil type and local traditions, slash and burn remains relatively the same in all regions. Agro-ecological intensification and the integration of livestock and agriculture is 2-3 decades old. Different alternatives have been tested, particularly the introduction of leguminous (covering the land or forming trees) to improve the soil and to build a bank of proteins for cattle. New techniques for the recuperation of pasture lands have become widely popular among ranches. The introduction of one or two annual plantations between two pasture areas allows reestablishing fertility through the injection of nitrates and, as a result, increases the pasture?s productivity. However, being relatively high-cost because of its demand in terms of mechanization and inputs, this technique is almost unaffordable for small Amazonian farmers..

A perspectiva arquipelágica: Açores

"[…]. Dada a inexistência de um catálogo nacional ou regional de espécies ameaçadas, e considerando que muitas das espécies endémicas dos Açores, raras e sujeitas a várias ameaças, não se encontram abrangidas por directivas e convenções internacionais, nem foram alvo de avaliação por nenhum tipo de critérios (IUCN ou outros), houve necessidade de uma definição de prioridades em termos de acções de conservação baseada numa fundamentação tanto quanto possível clara e objectiva. Nesse sentido, a lista agora apresentada permite-nos realizar uma análise de prioridades para os Açores. Com base nos mesmos critérios e pontuações já referidos em capítulos anteriores, organizou-se o Top 100 dos Açores, listagem que permitirá a prioritização de esforços e recursos (humanos, financeiros ou outros) a nível regional de forma objectiva, previamente acordada entre os intervenientes (gestores e cientistas). Pretende-se assim diminuir a subjectividade que, mais frequentemente do que é em geral admitido, está inerente à atribuição de recursos para a conservação do nosso património natural." [da Introdução

Fly-Tox: A panel of transgenic flies expressing pest and pollinator cytochrome P450s

This is the final version. Available from the publisher via the DOI in this record.There is an on-going need to develop new insecticides that are not compromised by resistance and that have improved environmental profiles. However, the cost of developing novel compounds has increased significantly over the last two decades. This is in part due to increased regulatory requirements, including the need to screen both pest and pollinator insect species to ensure that pre-existing resistance will not hamper the efficacy of a new insecticide via cross-resistance, or adversely affect non-target insect species. To add to this problem the collection and maintenance of toxicologically relevant pest and pollinator species and strains is costly and often difficult. Here we present Fly-Tox, a panel of publicly available transgenic Drosophila melanogaster lines each containing one or more pest or pollinator P450 genes that have been previously shown to metabolise insecticides. We describe the range of ways these tools can be used, including in predictive screens to avoid pre-existing cross-resistance, to identify potential resistance-breaking inhibitors, in the initial assessment of potential insecticide toxicity to bee pollinators, and identifying harmful pesticide-pesticide interactions.European Research Council (ERC)European Union's Horizon 2020 research and innovation programmeBiotechnology and Biological Sciences Research Council (BBSRC

Biometrically linking document leakage to the individuals responsible

Insider threats are a significant security issue. The last decade has witnessed countless instances of data loss and exposure in which data has become publicly available and easily accessible. Losing or disclosing sensitive data or confidential information may cause substantial financial and reputational damage to a company. Whilst more recent research has specifically focused on the insider misuse problem, it has tended to focus on the information itself – either through its protection or approaches to detect leakage. In contrast, this paper presents a proactive approach to the attribution of misuse via information leakage using biometrics and a locality-sensitive hashing scheme. The hash digest of the object (e.g. a document) is mapped with the given biometric information of the person who interacted with it and generates a digital imprint file that represents the correlation between the two parties. The proposed approach does not directly store or preserve any explicit biometric information nor document copy in a repository. It is only the established correlation (imprint) is kept for the purpose of reconstructing the mapped information once an incident occurred. Comprehensive experiments for the proposed approach have shown that it is highly possible to establish this correlation even when the original version has undergone significant file modification. In many scenarios, such as changing the file format r removing parts of the document, including words and sentences, it was possible to extract and reconstruct the correlated biometric information out of a modified document (e.g. 100 words were deleted) with an average success rate of 89.31%

Carbon-cryogel hierarchical composites as effective and scalable filters for removal of trace organic pollutants from water

Effective technologies are required to remove organic micropollutants from large fluid volumes to overcome present and future challenges in water and effluent treatment. A novel hierarchical composite filter material for rapid and effective removal of polar organic contaminants from water was developed. The composite is fabricated from phenolic resin-derived carbon microbeads with controllable porous structure and specific surface area embedded in a monolithic, flow permeable, poly(vinyl alcohol) cryogel. The bead-embedded monolithic composite filter retains the bulk of the high adsorptive capacity of the carbon microbeads while improving pore diffusion rates of organic pollutants. Water spiked with organic contaminants, both at environmentally relevant concentrations and at high levels of contamination, was used to determine the purification limits of the filter. Flow through tests using water spiked with the pesticides atrazine (32 mg/L) and malathion (16 mg/L) indicated maximum adsorptive capacities of 641 and 591 mg pollutant/g carbon, respectively. Over 400 bed volumes of water contaminated with 32 mg atrazine/L, and over 27,400 bed volumes of water contaminated with 2 μg atrazine/L, were treated before pesticide guideline values of 0.1 μg/L were exceeded. High adsorptive capacity was maintained when using water with high total organic carbon (TOC) levels and high salinity. The toxicity of water filtrates was tested in vitro with human epithelial cells with no evidence of cytotoxicity after initial washing

DRhoGEF2 Regulates Cellular Tension and Cell Pulsations in the Amnioserosa during Drosophila Dorsal Closure

Coordination of apical constriction in epithelial sheets is a fundamental process during embryogenesis. Here, we show that DRhoGEF2 is a key regulator of apical pulsation and constriction of amnioserosal cells during Drosophila dorsal closure. Amnioserosal cells mutant for DRhoGEF2 exhibit a consistent decrease in amnioserosa pulsations whereas overexpression of DRhoGEF2 in this tissue leads to an increase in the contraction time of pulsations. We probed the physical properties of the amnioserosa to show that the average tension in DRhoGEF2 mutant cells is lower than wild-type and that overexpression of DRhoGEF2 results in a tissue that is more solid-like than wild-type. We also observe that in the DRhoGEF2 overexpressing cells there is a dramatic increase of apical actomyosin coalescence that can contribute to the generation of more contractile forces, leading to amnioserosal cells with smaller apical surface than wild-type. Conversely, in DRhoGEF2 mutants, the apical actomyosin coalescence is impaired. These results identify DRhoGEF2 as an upstream regulator of the actomyosin contractile machinery that drives amnioserosa cells pulsations and apical constriction