泥炭的腐殖化度与全新世气候环境

泥炭是第四纪，特别是全新世以来的产物。它的形成和积累主要受控于气候，其次是地质、地貌、水文等因素。因此，泥炭形成过程中包含了大量的古气候、古环境演化信息。腐殖化度在国外早已用于古气候研究，国外学者将它作为湿度代用指标，用以恢复古湿度变迁。本文首次将之引入我国泥炭古气候研究，同时结合青藏高原的气候特点，及泥炭形成过程中温度、湿度对它的影响，赋予了泥炭腐殖化度新的气候内涵。即泥炭的腐殖化度高，指示气候温暖湿润；泥炭的腐殖化度低，指示气候干燥寒冷。本文通过对青藏高原东北部红原泥炭的腐殖化度研究，并与其它研究成果对比，得出如下结论：（1）红原泥炭腐殖化度记录了过去12000年以来当地气候干湿冷暖的变化。其气候变化大致可分为3个阶段：11.8-11.2 kaBP，气候干燥寒冷；11.2-5.5 ka BP，气候温暖湿润；5.5-0 ka BP，当地气候由早中全新世温暖湿润的气候向干燥寒冷的气候波动。红原泥炭腐殖化度记录的气候变化与高原青海湖沉积物、松西错沉积物、敦德冰芯、古里雅冰芯记录的气候变化相似，表明青藏高原12000年以来可能受同一气候系统影响，其气候变化的共同特点为干冷与暖湿交替。（2）泥炭腐殖化度记录了12000年以来印度西南季风在高原的强弱演化。新仙女木期（11.8-11.2kaBP），季风强度最弱；从11.2kaBP到10.8kaBP季风强度快速增强；在10.8ka即到5.5 ka BP，季风强度一直处于强势阶段；从5.5 ka BP开始，印度西南季风强度逐渐减弱，这期间腐殖化度同时记录了百年一千年尺度印度西南季风增强事件，但总体减弱的趋势不变。（3）泥炭腐殖化度记录的百年一千年气候突然变化事件与北大西洋浮冰事件存在遥相关。对应8次浮冰事件，红原地区气候同时变得干冷，而印度西南季风强度也减弱，这表明不但末次冰期印度西南季风与北大西洋气候密切相关，而且在全新世，这种相关性同样存在。（4）泥炭腐殖化度距平值较好的反映了西太平洋副热带高压近5000年来的活动变化。腐殖化度代用指标能很好地记录较长时间西太平洋副热带高压的变化，而对西太平洋副热带高压数十年到百年的频繁波动，则记录不明显。（5）泥炭腐殖化度时间序列的功率谱分析表明，太阳活动对红原地区气．候演化有重要影响，同时太阳活动通过影响全球水循环，进而驱动温盐环流的变化，进一步影响全球气候变化。（6）泥炭腐殖化度能同时记录温度、湿度的变化，并且测定方法简便、快捷，值得进一步研究。

中国企业员工组织承诺研究

The research objectives were to investigate the psychological structure of employees' organizational commitments(OCs), and its antecedents, and to examine the relative effects of employees' OCs to their performances. In order to deeply uncover the nature of OCs, some standard methods, such as in-depth interview, focus-group, semi-open questionnaire, standard questionnaire etc., were employed. In data analysis, not only some common statistical methods, such as multivariate analysis of variance, cross-table analysis, factor analysis, but also some forefront ones, such as confirmatory factor analysis and path analysis of SEM, were used. The paper covers six chapters: 1) In the first chapter, Firstly some previous empirical studies, which examined structures, antecedents, correlates, and/or consequences of organizational commitment in China and Western countries, were summarized. This summary covers most of the respectable researchers' works of this field, such as H.S.Becker, B.Buchanan, L.W.Porter, G. Ritzer, H.M.Trice, J.A.Alutto, L.G.Hrebiniak, R.T.Mowday, J.P.Meyer, N.J.Allen, G.W.McGee, R.C.Ford, R.Eisenberger, etc. Then three theoretical hypothesis were put forward as following: ① In China, OCs should be multidimensional psychological structures, which means there should exist more than one type of OCs; ② There should be some different antecedents to different OCs; ③ Employees with different types of OC should perform differently in their works. Finally the theoretical and practical significance were discussed. 2) In the second chapter, great efforts were made to investigate the OC types. Firstly, in-depth interview with managers and employees, semi-open questionnaire, and some other methods were used in the pilot research to gather much qualitative material. Then OC questionnaire was designed to get quantitative data in about 20 enterprises, including state-owned, collective-owned, wholly foreign-funded, and joint-ventures. During revising of this questionnaire, there were about 5000 samples surveyed. after factor analysis, the data shows that there should be 5 types of OCs in China, which were respectively named as Affective Commitment, Normative commitment, Ideal Commitment, Economic Commitment, Choice Commitment. Thirdly, confirmatory factor analysis method was used to successfully confirm this 5-factor model. Finally, Cronbach a and test-retest correlate indicate that this questionnaire is reliable. Since factor analysis result has show its construct validity, a simple criterion-related validity research was conducted. 3) In order to investigate the correlation between different OC and employee performance and different antecedents of OC, 5 other questionnaires, such as Employee Satisfaction Questionnaire, Perceived Organizational Support Questionnaire, Social Exchange Questionnaire, Altruism Scale, and Leader Confidence Scale were revised in the third chapter. 4)In the fourth chapter, a lot of correlates, cross-table analysis were conducted to show the correlation between different OCs and 10 performances, which indicate employees with different OCs will show different performance in 10 variables, such as altruism, etc. 5) In the fifth chapter, correlate analysis, multivariate of analysis, and path analysis of SEM were used to investigate the antecedents of OC. A satisfactory model showing the correlation between OC and their antecedents was confirmed. 6) In the last chapter, all researches about OC, and its limitations were summarized.

Xanthine oxidase pathway and muscle damage: Insights from McArdle disease

The intent of this review is to summarize current body of knowledge on the potential implication of the xanthine oxidase pathway (XO) on skeletal muscle damage. The possible involvement of the XO pathway in muscle damage is exemplified by the role of XO inhibitors (e.g., allopurinol) in attenuating muscle damage. Reliance on this pathway (as well as on the purine nucleotide cycle) could be exacerbated in conditions of low muscle glycogen availability. Thus, we also summarize current hypotheses on the etiology of both baseline and exertional muscle damage in McArdle disease, a condition caused by inherited deficiency of myophosphorylase. Because myophosphorylase catalyzes the first step of muscle glycogen breakdown, patients are unable to obtain energy from their muscle glycogen stores. Finally, we provide preliminary data from our laboratory on the potential implication of the XO pathway in the muscle damage that is commonly experienced by these patients.

Optymalizacja metod analizy Főrsterowskiego rezonansowego przeniesienia energii (FRET) pojedynczych cząsteczek

Wydział Chemii: Zakład Chemii Fizycznej

Tecnologias CAC e Inquéritos de Percepção da Opinião Pública sobre “O papel da Captação e do Armazenamento/Sequestração de Dióxido de Carbono no Futuro da Energia na Europa”:O caso-de-estudo da Comunidade Fernando Pessoa

O carvão e outros combustíveis fósseis, continuarão a ser, por décadas, a principal matéria-prima energética para as Centrais Térmicas, não obstante os esforços para, dentro do possível, substituir os combustíveis fósseis por fontes de energia renovável.Tal como está, hoje, bem documentado, a produção de gases com efeito estufa (GEE), designadamente CO2, resulta da combustão dos ditos combustíveis fósseis, sendo que se espera ser possível mitigar substancialmente a emissão de tais gases com a aplicação das chamadas Tecnologias Limpas do Carvão.Há, pois, necessidade de promover o abatimento do CO2 através de Tecnologias de Emissão Zero ou Tecnologias Livres de Carbono, incluindo designadamente a Captura, o Transporte e a Sequestração geológica de CO2 correspondentes ao que é costume designar por Tecnologias CAC (Captação e Armazenamento de Carbono). De facto, tais tecnologias e, designadamente, o armazenamento geológico de CO2 são as únicas que, no estado actual do conhecimento, são capazes de permitir que se cumpram as metas do ambicioso programa da EU para a energia e o ambiente conhecido por “20 20 para 2020” em conjugação com os aspectos económicos das directivas relativas ao Comércio Europeu de Licenças de Emissão – CELE (Directivas 2003/87/EC, 2004/101/EC e 2009/29/EC).A importância do tema está, aliás, bem demonstrada com o facto da Comissão Europeia ter formalmente admitido que as metas supracitadas serão impossíveis de atingir sem Sequestração Geológica de CO2. Esta é, pois, uma das razões de ter sido recentemente publicada a Directiva Europeia 2009/31/EC de 23 de Abril de 2009 expressamente dedicada ao tema do Armazenamento Geológico de CO2.Ora, a questão do armazenamento geológico de CO2 implica, para além das Tecnologias CAC acima mencionadas e da sua viabilização em termos tanto técnicos como económicos, ou seja, neste último aspecto, competitiva com o sistema CELE, também o conhecimento, da percepção pública sobre o assunto. Isto é, a praticabilidade das Tecnologias CAC implica que se conheça a opinião pública sobre o tema e, naturalmente, que face a esta realidade se prestem os esclarecimentos necessários como, aliás, é reconhecido na própria Directiva Europeia 2009/31/EC.Dado que a Fundação Fernando Pessoa / Universidade Fernando Pessoa através do seu Centro de Investigação em Alterações Globais, Energia, Ambiente e Bioengenharia – CIAGEB tem ultimado um Projecto de Engenharia relativo à Sequestração Geológica de CO2 nos Carvões (Metantracites) da Bacia Carbonífera do Douro – o Projecto COSEQ, preocupou-se naturalmente, desde o início, com o lançamento de inquéritos de percepção da opinião pública sobre o assunto.Tal implicou, nesta fase, a tradução para português e o lançamento do inquérito europeu ACCSEPT que não tinha sido ainda formalmente lançado de forma generalizada entre nós. Antes, porém, de lançar publicamente tal inquérito – o que está actualmente já em curso – resolveu-se testar o método de lançamento, a recolha de dados e o seu tratamento com uma amostra correspondente ao que se designou por Comunidade Fernando Pessoa, i.e. o conjunto de docentes, discentes, funcionários e outras pessoas relacionadas com a Universidade Fernando Pessoa (cerca de 5000 individualidades).Este trabalho diz, precisamente, respeito à preparação, lançamento e análise dos resultados do dito inquérito Europeu ACCSEPT a nível da Comunidade Fernando Pessoa. Foram recebidas 525 respostas representando 10,5% da amostra. A análise de resultados foi sistematicamente comparada com os obtidos nos outros países europeus, através do projecto ACCSEPT e, bem assim, com os resultados obtidos num inquérito homólogo lançado no Brasil. The use of coal, and other fossil fuels, will remain for decades as the main source of energy for power generation, despite the important efforts made to replace, as far as possible, fossil fuels with renewable power sources.As is well documented, the production of Greenhouse Gases (GHG), mainly CO2, arises primarily from the combustion of fossil fuels. The increasing application of Clean Coal Technologies-CCTs, is expected to mitigate substantially against the emission of such gases.There is consequently a need to promote the CO2 abatement through Zero Emission (Carbon Free) Technologies - ZETs, which includes CO2 capture, transport and geological storage, i.e. the so-called CCS (Carbon, Capture and Storage) technologies. In fact, these technologies are the only ones that are presently able to conform to the ambitious EU targets set out under the “20 20 by 2020” EU energy and environment programme, jointly with the economic aspects of the EU Directives 2003/87/EC, 2004/101/EC and 2009/29/EC concerned with the Greenhouse Gas Emissions Allowance Trading Scheme – ETS scheme. The European Commission formal admission that the referred targets will be impossible to reach without the implementation and contribution of geological storage clearly demonstrate the importance of this particular issue, and for this reason the EC Directive 2009/31/EC of April 23, 2009 on Geological Storage of CO2 was recently published.In considering the technical and economical viabilities of CCS technologies, the latter in competition with the ETS scheme, it is believed that public perception will dictate the success of the development and implementation of CO2 geological storage at a large industrial level. This means that, in order to successfully implement CCS technologies, not only must public opinion be taken into consideration but objective information must also be provided to the public in order to raise subject awareness, as recognized in the referred Directive 2009/31/EC.In this context, the Fernando Pessoa Foundation / University Fernando Pessoa, through its CIAGEB (Global Change, Energy, Environment and Bioengineering) RDID&D Unit, is the sponsor of an Engineering Project for the Geological Sequestration of CO2 in Douro Coalfield Meta-anthracites - the COSEQ Project, and is therefore also engaged in public perception surveys with regards to CCS technologies.At this stage, the original European ACCSEPT inquiry was translated to Portuguese and submitted only to the “Fernando Pessoa Community” - comprising university lecturers, students, other employees, as well as, former students and persons that have a professional or academic relationship with the university (c. 5000 individuals). The results obtained from this first inquiry will be used to improve the survey informatics system in terms of communication, database, and data treatment prior to resubmission of the inquiry to the Portuguese public at large.The present publication summarizes the process and the results obtained from the ACCSEPT survey distributed to the “Fernando Pessoa Community”. 525 replies, representing 10.5% of the sample, have been received and analysed. The assessment of the results was systematically compared with those obtained from other European Countries, as reported by the ACCSEPT inquiry, as well as with those from an identical inquiry launched in Brazil.

Independent evolutionary origins of landlocked alewife populations and rapid parallel evolution of phenotypic traits.

Alewife, Alosa pseudoharengus, populations occur in two discrete life-history variants, an anadromous form and a landlocked (freshwater resident) form. Landlocked populations display a consistent pattern of life-history divergence from anadromous populations, including earlier age at maturity, smaller adult body size, and reduced fecundity. In Connecticut (USA), dams constructed on coastal streams separate anadromous spawning runs from lake-resident landlocked populations. Here, we used sequence data from the mtDNA control region and allele frequency data from five microsatellite loci to ask whether coastal Connecticut landlocked alewife populations are independently evolved from anadromous populations or whether they share a common freshwater ancestor. We then used microsatellite data to estimate the timing of the divergence between anadromous and landlocked populations. Finally, we examined anadromous and landlocked populations for divergence in foraging morphology and used divergence time estimates to calculate the rate of evolution for foraging traits. Our results indicate that landlocked populations have evolved multiple times independently. Tests of population divergence and estimates of gene flow show that landlocked populations are genetically isolated, whereas anadromous populations exchange genes. These results support a 'phylogenetic raceme' model of landlocked alewife divergence, with anadromous populations forming an ancestral core from which landlocked populations independently diverged. Divergence time estimates suggest that landlocked populations diverged from a common anadromous ancestor no longer than 5000 years ago and perhaps as recently as 300 years ago, depending on the microsatellite mutation rate assumed. Examination of foraging traits reveals landlocked populations to have significantly narrower gapes and smaller gill raker spacings than anadromous populations, suggesting that they are adapted to foraging on smaller prey items. Estimates of evolutionary rates (in haldanes) indicate rapid evolution of foraging traits, possibly in response to changes in available resources.

Mechanisms of CD8+ T Cell Mediated Virus Inhibition in HIV-1 Virus Controllers

CD8+ T cells are associated with long term control of virus replication to low or undetectable levels in a population of HIV+ therapy-naïve individuals known as virus controllers (VCs; <5000 RNA copies/ml and CD4+ lymphocyte counts >400 cells/µl). These subjects' ability to control viremia in the absence of therapy makes them the gold standard for the type of CD8+ T-cell response that should be induced with a vaccine. Studying the regulation of CD8+ T cells responses in these VCs provides the opportunity to discover mechanisms of durable control of HIV-1. Previous research has shown that the CD8+ T cell population in VCs is heterogeneous in its ability to inhibit virus replication and distinct T cells are responsible for virus inhibition. Further defining both the functional properties and regulation of the specific features of the select CD8+ T cells responsible for potent control of viremia the in VCs would enable better evaluation of T cell-directed vaccine strategies and may inform the design of new therapies.

Here we discuss the progress made in elucidating the features and regulation of CD8+ T cell response in virus controllers. We first detail the development of assays to quantify CD8+ T cells' ability to inhibit virus replication. This includes the use of a multi-clade HIV-1 panel which can subsequently be used as a tool for evaluation of T cell directed vaccines. We used these assays to evaluate the CD8+ response among cohorts of HIV-1 seronegative, HIV-1 acutely infected, and HIV-1 chronically infected (both VC and chronic viremic) patients. Contact and soluble CD8+ T cell virus inhibition assays (VIAs) are able to distinguish these patient groups based on the presence and magnitude of the responses. When employed in conjunction with peptide stimulation, the soluble assay reveals peptide stimulation induces CD8+ T cell responses with a prevalence of Gag p24 and Nef specificity among the virus controllers tested. Given this prevalence, we aimed to determine the gene expression profile of Gag p24-, Nef-, and unstimulated CD8+ T cells. RNA was isolated from CD8+ T-cells from two virus controllers with strong virus inhibition and one seronegative donor after a 5.5 hour stimulation period then analyzed using the Illumina Human BeadChip platform (Duke Center for Human Genome Variation). Analysis revealed that 565 (242 Nef and 323 Gag) genes were differentially expressed in CD8+ T-cells that were able to inhibit virus replication compared to those that could not. We compared the differentially expressed genes to published data sets from other CD8+ T-cell effector function experiments focusing our analysis on the most recurring genes with immunological, gene regulatory, apoptotic or unknown functions. The most commonly identified gene in these studies was TNFRSF9. Using PCR in a larger cohort of virus controllers we confirmed the up-regulation of TNFRSF9 in Gag p24 and Nef-specific CD8+ T cell mediated virus inhibition. We also observed increase in the mRNA encoding antiviral cytokines macrophage inflammatory proteins (MIP-1α, MIP-1αP, MIP-1β), interferon gamma (IFN-γ), granulocyte-macrophage colony-stimulating factor (GM-CSF), and recently identified lymphotactin (XCL1).

Our previous work suggests the CD8+ T-cell response to HIV-1 can be regulated at the level of gene regulation. Because RNA abundance is modulated by transcription of new mRNAs and decay of new and existing RNA we aimed to evaluate the net rate of transcription and mRNA decay for the cytokines we identified as differentially regulated. To estimate rate of mRNA synthesis and decay, we stimulated isolated CD8+ T-cells with Gag p24 and Nef peptides adding 4-thiouridine (4SU) during the final hour of stimulation, allowing for separation of RNA made during the final hour of stimulation. Subsequent PCR of RNA isolated from these cells, allowed us to determine how much mRNA was made for our genes of interest during the final hour which we used to calculate rate of transcription. To assess if stimulation caused a change in RNA stability, we calculated the decay rates of these mRNA over time. In Gag p24 and Nef stimulated T cells , the abundance of the mRNA of many of the cytokines examined was dependent on changes in both transcription and mRNA decay with evidence for potential differences in the regulation of mRNA between Nef and Gag specific CD8+ T cells. The results were highly reproducible in that in one subject that was measured in three independent experiments the results were concordant.

This data suggests that mRNA stability, in addition to transcription, is key in regulating the direct anti-HIV-1 function of antigen-specific memory CD8+ T cells by enabling rapid recall of anti-HIV-1 effector functions, namely the production and increased stability of antiviral cytokines. We have started to uncover the mechanisms employed by CD8+ T cell subsets with antigen-specific anti-HIV-1 activity, in turn, enhancing our ability to inhibit virus replication by informing both cure strategies and HIV-1 vaccine designs that aim to reduce transmission and can aid in blocking HIV-1 acquisition.

Adjuvant portal-vein infusion of fluorouracil and heparin in colorectal cancer: A randomised trial

Background. There is conflicting evidence on the efficacy of regional adjuvant chemotherapy, via portal-vein infusion (PVI), after resection of colorectal cancer. We undertook a randomised controlled multicentre trial to investigate the efficacy of PVI (500 mg/m2 fluorouracil plus 5000 IU heparin daily for 7 days). Methods. 1235 of about 1500 potentially eligible patients were randomly assigned surgery plus PVI or surgery alone (control). The patients were followed up for a median of 63 months, with yearly screening for recurrent disease. The primary endpoint was survival; analyses were by intention to treat. Findings. 619 patients in the control group and 616 in the PVI group met eligibility criteria. 164 (26%) control-group patients and 173 (28%) PVI-group patients died. 5-year survival did not differ significantly between the groups (73 vs 72%; 95% CI for difference -6 to 4). The control and PVI groups were also similar in terms of disease-free survival at 5 years (67 vs 65%) and the number of patients with liver metastases (79 vs 77%). Interpretation. PVI of fluorouracil, at a dose of 500 mg/m2 for 7 days, cannot be recommended as the sole adjuvant treatment for high-risk colorectal cancer after complete surgical excision. However, these results cannot eliminate a small benefit when PVI is used at a higher dosage or in combination with mitomycin.

Pastoreo estratégico de ambientes para mejorar la producción ovina en campos del ecotono bosque-estepa en Patagonia Sur

La conservación de los bosques nativos de ñire (Nothofagus antarctica) en establecimientos bajo manejo ganadero extensivo, se presenta como un desafío de manejo dadas las condiciones climáticas y la configuración de los ambientes en los grandes potreros (300-5000 ha) propios de estancias de Santa Cruz y Tierra del Fuego. Por ello, inicialmente se relevaron los establecimientos con bosque de ñire en esta región con el objetivo principal de conocer el nivel de manejo y sus características ganaderas. Como resultado se encontraron bajos índices de aplicación de tecnologías que propiciaron la realización de una propuesta de manejo integral del recurso forestal y pastoril a escala de establecimiento y durante toda la temporada de producción. Esta propuesta incluyó la separación de ambientes y su uso en época adecuada, protección de renovales de ñire e intensificación del esquema de pastoreo mediante un mayor número de potreros de menor tamaño. Para el establecimiento bajo estudio, la respuesta animal al manejo propuesto manifestó resultados superadores en la producción de carne y lana comparada con el manejo tradicional, así como también se encontraron resultados positivos en la continuidad del estrato arbóreo a través de la protección individual de renovales y en la conservación del recurso forrajero principalmente en áreas sensibles como los mallines. Por otra parte, se advirtió la importancia del ajuste de carga sobre la producción animal individual en períodos críticos del año. Finalmente, se complementó el estudio de las variables de producción con variables relacionadas al comportamiento animal (dieta, actividades diarias y uso espacial de ambientes con el uso de collares GPS). De su análisis fue posible deducir que la intensificación de manejo propuesta, bajo las condiciones ensayadas, no afecta la conducta de los ovinos en pastoreo, destacando además la preferencia de los animales por el ambiente de bosque por su reparo y consumo de forraje disponible en épocas críticas del año. Este estudio, a escala real de producción, brinda mayor conocimiento para la definición de tecnologías de manejo ovino en campos con bosques de ñire.

The use of fluorescence microscopy to define polymer localisation to the late endocytic compartments in cells that are targets for drug delivery

Macromolecular therapeutics and nano-sized drug delivery systems often require localisation to specific intracellular compartments. In particular, efficient endosomal escape, retrograde trafficking, or late endocytic/lysosomal activation are often prerequisites for pharmacological activity. The aim of this study was to define a fluorescence microscopy technique able to confirm the localisation of water-soluble polymeric carriers to late endocytic intracellular compartments. Three polymeric carriers of different molecular weight and character were studied: dextrin (Mw~50,000 g/mol), a N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer (Mw approximately 35,000 g/mol) and polyethylene glycol (PEG) (Mw 5000 g/mol). They were labelled with Oregon Green (OG) (0.3-3 wt.%; <3% free OG in respect of total). A panel of relevant target cells were used: THP-1, ARPE-19, and MCF-7 cells, and primary bovine chondrocytes (currently being used to evaluate novel polymer therapeutics) as well as NRK and Vero cells as reference controls. Specific intracellular compartments were marked using either endocytosed physiological standards, Marine Blue (MB) or Texas-red (TxR)-Wheat germ agglutinin (WGA), TxR-Bovine Serum Albumin (BSA), TxR-dextran, ricin holotoxin, C6-7-nitro-2,1,3-benzoxadiazol-4-yl (NBD)-labelled ceramide and TxR-shiga toxin B chain, or post-fixation immuno-staining for early endosomal antigen 1 (EEA1), lysosomal-associated membrane proteins (LAMP-1, Lgp-120 or CD63) or the Golgi marker GM130. Co-localisation with polymer-OG conjugates confirmed transfer to discreet, late endocytic (including lysosomal) compartments in all cells types. The technique described here is a particularly powerful tool as it circumvents fixation artefacts ensuring the retention of water-soluble polymers within the vesicles they occupy.

Modelling large-scale CO2 leakages in the North Sea

A three dimensional hydrodynamic model with a coupled carbonate speciation sub-model is used to simulate large additions of CO2into the North Sea, representing leakages at potential carbon sequestration sites. A range of leakage scenarios are conducted at two distinct release sites, allowing an analysis of the seasonal, inter-annual and spatial variability of impacts to the marine ecosystem. Seasonally stratified regions are shown to be more vulnerable to CO2release during the summer as the added CO2remains trapped beneath the thermocline, preventing outgasing to the atmosphere. On average, CO2 injected into the northern North Sea is shown to reside within the water column twice as long as an equivalent addition in the southern North Sea before reaching the atmosphere. Short-term leakages of 5000 tonnes CO2over a single day result in substantial acidification at the release sites (up to -1.92 pH units), with significant perturbations (greater than 0.1 pH units) generally confined to a 10 km radius. Long-term CO2leakages sustained for a year may result in extensive plumes of acidified seawater, carried by major advective pathways. Whilst such scenarios could be harmful to marine biota over confined spatial scales, continued unmitigated CO2emissions from fossil fuels are predicted to result in greater and more long-lived perturbations to the carbonate system over the next few decades.

CoastColour Round Robin datasets: a database to evaluate the performance of algorithms for the retrieval of water quality parameters in coastal waters.

The use of in situ measurements is essential in the validation and evaluation of the algorithms that provide coastal water quality data products from ocean colour satellite remote sensing. Over the past decade, various types of ocean colour algorithms have been developed to deal with the optical complexity of coastal waters. Yet there is a lack of a comprehensive intercomparison due to the availability of quality checked in situ databases. The CoastColour Round Robin (CCRR) project, funded by the European Space Agency (ESA), was designed to bring together three reference data sets using these to test algorithms and to assess their accuracy for retrieving water quality parameters. This paper provides a detailed description of these reference data sets, which include the Medium Resolution Imaging Spectrometer (MERIS) level 2 match-ups, in situ reflectance measurements, and synthetic data generated by a radiative transfer model (HydroLight). These data sets, representing mainly coastal waters, are available from doi:10.1594/PANGAEA.841950. The data sets mainly consist of 6484 marine reflectance (either multispectral or hyperspectral) associated with various geometrical (sensor viewing and solar angles) and sky conditions and water constituents: total suspended matter (TSM) and chlorophyll a (CHL) concentrations, and the absorption of coloured dissolved organic matter (CDOM). Inherent optical properties are also provided in the simulated data sets (5000 simulations) and from 3054 match-up locations. The distributions of reflectance at selected MERIS bands and band ratios, CHL and TSM as a function of reflectance, from the three data sets are compared. Match-up and in situ sites where deviations occur are identified. The distributions of the three reflectance data sets are also compared to the simulated and in situ reflectances used previously by the International Ocean Colour Coordinating Group (IOCCG, 2006) for algorithm testing, showing a clear extension of the CCRR data which covers more turbid waters.

The Holocene British and Irish ancient woodland fossil beetle fauna: implications for forest history, biodiversity and faunal colonisation

This paper presents a new review of our knowledge of the ancient forest beetle fauna from Holocene archaeological and palaeoecological sites in Great Britain and Ireland. It examines the colonisation, dispersal and decline of beetle species, highlighting the scale and nature of human activities in the shaping of the landscape of the British Isles. In particular, the paper discusses effects upon the insect fauna, and examines in detail the fossil record from the Humberhead Levels, eastern England. It discusses the local extirpation of up to 40 species in Britain and 15 species in Ireland. An evaluation of the timing of extirpations is made, suggesting that many species in Britain disappear from the fossil record between c. 3000 cal BC and 1000 cal BC (c. 5000-3000 cal BP), although some taxa may well have survived until considerably later. In Ireland, there are two distinct trends, with a group of species which seem to be absent after c. 2000 cal BC (c. 4000 cal BP) and a further group which survives until at least as late as the medieval period. The final clearance of the Irish landscape over the last few hundred years was so dramatic, however, that some species which are not especially unusual in a British context were decimated. Reasons behind the extirpation of taxa are examined in detail, and include a combination of forest clearance and human activities, isolation of populations, lack of temporal continuity of habitats, edaphic and competition factors affecting distribution of host trees (particularly pine), lack of forest fires and a decline in open forest systems. The role of climate change in extirpations is also evaluated. Consideration is given to the significance of these specialised ancient forest inhabitants in Ireland in the absence of an early Holocene land-bridge which suggests that colonisation was aided by other mechanisms, such as human activities and wood-rafting. Finally, the paper discusses the Continental origins of the British and Irish fauna and its hosts and the role played by European glacial refugia.

The resistance of polyvinylpyrrolidone–Iodine–poly(e-caprolactone) blends to adherence of Escherichia coli

In this study, the resistance of biodegradable biomaterials, composed of blends of poly(e-caprolactone) (PCL) and the polymeric antimicrobial complex, polyvinylpyrrolidone–iodine (PVP-I) to the adherence of a clinical isolate of Escherichia coli is described. Blends of PCL composed of a range of high (50,000 g mol1) to low (5000 g mol1) molecular weight ratios of polymer and either
devoid of or containing PVP-I (1% w/w) were prepared by solvent evaporation. Following incubation (4 h), there was no relationship between m. wt. ratio of PCL in ?lms devoid of PVP-I and adherence ofE. coli. Conversely, microbial adherence to PCL containing PVP-I decreased as the ratio of high:low m. wt. polymer was decreased and was approximately 1000 fold lower than that to comparator ?lms devoid of PVP-I. Following periods of immersion of PVP-I containing PCL ?lms under sink conditions in phosphate buffered saline, subsequent adherence of E. coli was substantially reduced for 2 days (40:60 m. wt. ratio) and 6 days (100:0 m. wt. ratio). Concurrent exposure of PCL and E. coli to sub-minimum inhibitory concentrations (sub-MIC) of PVP-I signi?cantly reduced microbial adherence to the biomaterial; however, the molecular weight ratio of PCL did not affect this outcome. Pretreatment of PCL with similar sub-MIC of PVP-I prior to inclusion within the microbial adherence assay signi?cantly decreased the subsequent adherence of E. coli. Greatest reduction in adherence was observed following treatment of PCL (40:60 m. wt. ratio) with 0.0156% w/w PVP-I. In conclusion, this study has illustrated the utility of PVP-I as a suitable therapeutic agent for incorporation within PCL as a novel biomaterial. Due to the combined antimicrobial and biodegradable properties, these biomaterials offer a promising strategy for the reduction in medical device related infection. © 2004 Elsevier Ltd. All rights reserved.