Showing papers by "University of Exeter published in 2009"
TL;DR: In this article, the authors review insights from history, sociology and psychology of risk, economics and political science to develop four propositions concerning limits to adaptation and conclude that these issues of values and ethics, risk, knowledge, attitudes to risk and culture construct societal limits, but that these limits are mutable.
Abstract: While there is a recognised need to adapt to changing climatic conditions, there is an emerging discourse of limits to such adaptation. Limits are traditionally analysed as a set of immutable thresholds in biological, economic or technological parameters. This paper contends that limits to adaptation are endogenous to society and hence contingent on ethics, knowledge, attitudes to risk and culture. We review insights from history, sociology and psychology of risk, economics and political science to develop four propositions concerning limits to adaptation. First, any limits to adaptation depend on the ultimate goals of adaptation underpinned by diverse values. Second, adaptation need not be limited by uncertainty around future foresight of risk. Third, social and individual factors limit adaptation action. Fourth, systematic undervaluation of loss of places and culture disguises real, experienced but subjective limits to adaptation. We conclude that these issues of values and ethics, risk, knowledge and culture construct societal limits to adaptation, but that these limits are mutable.
2,159 citations
TL;DR: Model calculations and experimental observations consistently show that polyethylene accumulates more organic contaminants than other plastics such as polypropylene and polyvinyl chloride, and PCBs could transfer from contaminated plastics to streaked shearwater chicks.
Abstract: Plastics debris in the marine environment, including resin pellets, fragments and microscopic plastic fragments, contain organic contaminants, including polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons, petroleum hydrocarbons, organochlorine pesticides (2,2′-bis(p-chlorophenyl)-1,1,1-trichloroethane, hexachlorinated hexanes), polybrominated diphenylethers, alkylphenols and bisphenol A, at concentrations from sub ng g–1 to µg g–1. Some of these compounds are added during plastics manufacture, while others adsorb from the surrounding seawater. Concentrations of hydrophobic contaminants adsorbed on plastics showed distinct spatial variations reflecting global pollution patterns. Model calculations and experimental observations consistently show that polyethylene accumulates more organic contaminants than other plastics such as polypropylene and polyvinyl chloride. Both a mathematical model using equilibrium partitioning and experimental data have demonstrated the transfer of contaminants from plastic to organisms. A feeding experiment indicated that PCBs could transfer from contaminated plastics to streaked shearwater chicks. Plasticizers, other plastics additives and constitutional monomers also present potential threats in terrestrial environments because they can leach from waste disposal sites into groundwater and/or surface waters. Leaching and degradation of plasticizers and polymers are complex phenomena dependent on environmental conditions in the landfill and the chemical properties of each additive. Bisphenol A concentrations in leachates from municipal waste disposal sites in tropical Asia ranged from sub µg l–1 to mg l–1 and were correlated with the level of economic development.
2,114 citations
TL;DR: In this paper, the authors discuss the relationship between social identity and symptom appraisal and response, health-related norms and behaviour, social support, coping, and clinical outcomes, and point out the capacity for a social identity approach to enrich academic understanding in these areas and to play a key role in shaping healthrelated policy and practice.
Abstract: The social environment comprising communities, families, neighbourhoods, work teams, and various other forms of social group is not simply an external feature of the world that provides a context for individual behaviour. Instead these groups impact on the psychology of individuals through their capacity to be internalised as part of a person’s social identity. If groups provide individuals with a sense of meaning, purpose, and belonging (i.e. a positive sense of social identity) they tend to have positive psychological consequences. The impact of these identity processes on health and well-being is explored in the contributions to this special issue. In this editorial, we discuss these contributions in light of five central themes that have emerged from research to date. These themes address the relationship between social identity and (a) symptom appraisal and response, (b) health-related norms and behaviour, (c) social support, (d) coping, and (e) clinical outcomes. The special issue as a whole points to the capacity for a social identity approach to enrich academic understanding in these areas and to play a key role in shaping health-related policy and practice.
991 citations
02 Nov 2009
TL;DR: A novel probabilistic modeling framework based on Latent Dirichlet Allocation (LDA) is proposed, called joint sentiment/topic model (JST), which detects sentiment and topic simultaneously from text, which is fully unsupervised.
Abstract: Sentiment analysis or opinion mining aims to use automated tools to detect subjective information such as opinions, attitudes, and feelings expressed in text. This paper proposes a novel probabilistic modeling framework based on Latent Dirichlet Allocation (LDA), called joint sentiment/topic model (JST), which detects sentiment and topic simultaneously from text. Unlike other machine learning approaches to sentiment classification which often require labeled corpora for classifier training, the proposed JST model is fully unsupervised. The model has been evaluated on the movie review dataset to classify the review sentiment polarity and minimum prior information have also been explored to further improve the sentiment classification accuracy. Preliminary experiments have shown promising results achieved by JST.
983 citations
University College Dublin1, Massachusetts Institute of Technology2, Broad Institute3, University of Aveiro4, University of Aberdeen5, Boston University6, University of Minnesota7, Duke University8, Imperial College London9, Stanford University10, University of Exeter11, Leibniz Association12, University of Amsterdam13, Wellcome Trust Sanger Institute14, University of Illinois at Urbana–Champaign15, Stony Brook University16, Newcastle University17, University of Iowa18, University of Sheffield19, University of Texas Health Science Center at Houston20
TL;DR: There are significant expansions of cell wall, secreted and transporter gene families in pathogenic species, suggesting adaptations associated with virulence in Candida albicans species.
Abstract: Candida species are the most common cause of opportunistic fungal infection worldwide. Here we report the genome sequences of six Candida species and compare these and related pathogens and non-pathogens. There are significant expansions of cell wall, secreted and transporter gene families in pathogenic species, suggesting adaptations associated with virulence. Large genomic tracts are homozygous in three diploid species, possibly resulting from recent recombination events. Surprisingly, key components of the mating and meiosis pathways are missing from several species. These include major differences at the mating-type loci (MTL); Lodderomyces elongisporus lacks MTL, and components of the a1/2 cell identity determinant were lost in other species, raising questions about how mating and cell types are controlled. Analysis of the CUG leucine-to-serine genetic-code change reveals that 99% of ancestral CUG codons were erased and new ones arose elsewhere. Lastly, we revise the Candida albicans gene catalogue, identifying many new genes.
956 citations
TL;DR: This work shows how functional genomics approaches are providing new insight into the genetic control of plant infection by M. oryzae, and looks ahead to the key questions that need to be addressed to provide a better understanding of the molecular processes that lead to plant disease and the prospects for sustainable control of rice blast.
Abstract: The filamentous fungus Magnaporthe oryzae causes rice blast, the most serious disease of cultivated rice. Cellular differentiation of M. oryzae forms an infection structure called the appressorium, which generates enormous cellular turgor that is sufficient to rupture the plant cuticle. Here, we show how functional genomics approaches are providing new insight into the genetic control of plant infection by M. oryzae. We also look ahead to the key questions that need to be addressed to provide a better understanding of the molecular processes that lead to plant disease and the prospects for sustainable control of rice blast.
811 citations
TL;DR: The authors used the HadGEM2-A general circulation model to simulate the effect of late twentieth century "global dimming" and associated increases in the diffuse radiation fraction on global carbon storage.
Abstract: Increased exposure to solar radiation generally increases plant photosynthesis, but not all forms of radiation are equally effective. In particular, field studies have demonstrated that a given amount of diffuse radiation leads to more fixed carbon than direct radiation. Mercado et al. use the HadGEM2-A general circulation model to simulate the effect of late twentieth century 'global dimming' and associated increases in the diffuse radiation fraction on global carbon storage. They find that increases in diffuse radiation enhanced the terrestrial carbon sink by about 25%. Paradoxically, reducing anthropogenic pollution in the future would reduce this diffuse radiation effect, thereby creating a positive feedback to global warming. More radiation generally increases vegetation photosynthesis, but field studies show that a given amount of diffuse radiation leads to more fixed carbon than direct radiation. Mercado and colleagues simulate the effect of late twentieth century increases in the diffuse radiation fraction, and find that the terrestrial carbon sink is enhanced by about 25% —paradoxically, reducing future anthropogenic pollution will reduce this diffuse radiation effect, creating a positive feedback to global warming. Plant photosynthesis tends to increase with irradiance. However, recent theoretical and observational studies have demonstrated that photosynthesis is also more efficient under diffuse light conditions1,2,3,4,5. Changes in cloud cover or atmospheric aerosol loadings, arising from either volcanic or anthropogenic emissions, alter both the total photosynthetically active radiation reaching the surface and the fraction of this radiation that is diffuse, with uncertain overall effects on global plant productivity and the land carbon sink. Here we estimate the impact of variations in diffuse fraction on the land carbon sink using a global model modified to account for the effects of variations in both direct and diffuse radiation on canopy photosynthesis. We estimate that variations in diffuse fraction, associated largely with the ‘global dimming’ period6,7,8, enhanced the land carbon sink by approximately one-quarter between 1960 and 1999. However, under a climate mitigation scenario for the twenty-first century in which sulphate aerosols decline before atmospheric CO2 is stabilized, this ‘diffuse-radiation’ fertilization effect declines rapidly to near zero by the end of the twenty-first century.
805 citations
TL;DR: Numerous interactions between herbal medicines and conventional drugs have been documented, while the significance of many interactions is uncertain, several interactions, particularly those with St John’s wort, may have serious clinical consequences.
Abstract: The concomitant use of herbal medicines and pharmacotherapy is wide spread. We have reviewed the literature to determine the possible interactions between seven popular herbal medicines (ginkgo, St John's wort, ginseng, garlic, echinacea, saw palmetto and kava) and conventional drugs. Literature searches were performed using MEDLINE, Cochrane Library and EMBASE and we identified 128 case reports or case series, and 80 clinical trials. Clinical trials indicate that St John's wort (Hypericum perforatum), via cytochrome P450 (CYP) and/or P-glycoprotein induction, reduces the plasma concentrations (and/or increases the clearance) of alprazolam, amitriptyline, atorvastatin, chlorzoxazone, ciclosporin, debrisoquine, digoxin, erythromycin, fexofenadine, gliclazide, imatinib, indinavir, irinotecan, ivabradine, mephenytoin, methadone, midazolam, nifedipine, omeprazole, oral contraceptives, quazepam, simvastatin, tacrolimus, talinolol, verapamil, voriconazole and warfarin. Case reports or case series suggest interactions of St John's wort with adrenergic vasopressors, anaesthetics, bupropion, buspirone, ciclosporin, eletriptan, loperamide, nefazodone, nevirapine, oral contraceptives, paroxetine, phenprocoumon, prednisone, sertraline, tacrolimus, theophylline, tibolone, tryptophan, venlafaxine and warfarin. Ginkgo (Ginkgo biloba) decreases the plasma concentrations of omeprazole, ritonavir and tolbutamide. Clinical cases indicate interactions of ginkgo with antiepileptics, aspirin (acetylsalicylic acid), diuretics, ibuprofen, risperidone, rofecoxib, trazodone and warfarin. Ginseng (Panax ginseng) may interact with phenelzine and warfarin. Kava (Piper methysticum) increases the clearance of chlorzoxazone (a CYP2E1 substrate) and may interact with alprazolam, levodopa and paroxetine. Garlic (Allium sativum) interacts with chlorpropamide, fluindione, ritonavir and warfarin; it also reduces plasma concentrations of chlorzoxazone (a CYP2E1 probe). Echinacea might affect the clearance of caffeine (a CYP1A2 probe) and midazolam (a CYP3A4 probe). No interactions have been reported for saw palmetto (Serenoa repens). Numerous interactions between herbal medicines and conventional drugs have been documented. While the significance of many interactions is uncertain, several interactions, particularly those with St John's wort, may have serious clinical consequences.
708 citations
TL;DR: Most plasticizers appear to act by interfering with the functioning of various hormone systems, but some phthalates have wider pathways of disruption, and given the sensitivity of some invertebrates, effects assessments are warranted in other invertebrate phyla.
Abstract: This review provides a critical analysis of the biological effects of the most widely used plasticizers, including dibutyl phthalate, diethylhexyl phthalate, dimethyl phthalate, butyl benzyl phthalate and bisphenol A (BPA), on wildlife, with a focus on annelids (both aquatic and terrestrial), molluscs, crustaceans, insects, fish and amphibians. Moreover, the paper provides novel data on the biological effects of some of these plasticizers in invertebrates, fish and amphibians. Phthalates and BPA have been shown to affect reproduction in all studied animal groups, to impair development in crustaceans and amphibians and to induce genetic aberrations. Molluscs, crustaceans and amphibians appear to be especially sensitive to these compounds, and biological effects are observed at environmentally relevant exposures in the low ng l−1 to µg l−1 range. In contrast, most effects in fish (except for disturbance in spermatogenesis) occur at higher concentrations. Most plasticizers appear to act by interfering with the functioning of various hormone systems, but some phthalates have wider pathways of disruption. Effect concentrations of plasticizers in laboratory experiments coincide with measured environmental concentrations, and thus there is a very real potential for effects of these chemicals on some wildlife populations. The most striking gaps in our current knowledge on the impacts of plasticizers on wildlife are the lack of data for long-term exposures to environmentally relevant concentrations and their ecotoxicity when part of complex mixtures. Furthermore, the hazard of plasticizers has been investigated in annelids, molluscs and arthropods only, and given the sensitivity of some invertebrates, effects assessments are warranted in other invertebrate phyla.
697 citations
University of Leicester1, Pennsylvania State University2, University of Warwick3, Harvard University4, University of Copenhagen5, Max Planck Society6, Goddard Space Flight Center7, University of California, Berkeley8, University of Amsterdam9, University of Iceland10, University of Exeter11, University of Bristol12, Spanish National Research Council13, European Southern Observatory14, Australian National University15, Special Astrophysical Observatory16, Space Telescope Science Institute17, Universities Space Research Association18, California Institute of Technology19, Liverpool John Moores University20, Pomona College21, University of Oxford22, McGill University23, University College London24, Stockholm University25, George Washington University26
TL;DR: In this paper, the authors reported that GRB 090423 lies at a redshift of z approximate to 8.2, implying that massive stars were being produced and dying as GRBs similar to 630 Myr after the Big Bang.
Abstract: Long-duration gamma-ray bursts (GRBs) are thought to result from the explosions of certain massive stars(1), and some are bright enough that they should be observable out to redshifts of z > 20 using current technology(2-4). Hitherto, the highest redshift measured for any object was z = 6.96, for a Lyman-alpha emitting galaxy(5). Here we report that GRB 090423 lies at a redshift of z approximate to 8.2, implying that massive stars were being produced and dying as GRBs similar to 630 Myr after the Big Bang. The burst also pinpoints the location of its host galaxy.
689 citations
TL;DR: The results show that 3D modeling can be combined with measured data from multiple wavelengths to reconstruct chromophore concentrations within the tissue, and it is possible to recover scattering spectra, resulting from the dominant Mie-type scatter present in tissue.
Abstract: Diffuse optical tomography, also known as near infrared tomography, has been under investigation, for non-invasive functional imaging of tissue, specifically for the detection and characterization of breast cancer or other soft tissue lesions. Much work has been carried out for accurate modeling and image reconstruction from clinical data. NIRFAST, a modeling and image reconstruction package has been developed, which is capable of single wavelength and multi-wavelength optical or functional imaging from measured data. The theory behind the modeling techniques as well as the image reconstruction algorithms is presented here, and 2D and 3D examples are presented to demonstrate its capabilities. The results show that 3D modeling can be combined with measured data from multiple wavelengths to reconstruct chromophore concentrations within the tissue. Additionally it is possible to recover scattering spectra, resulting from the dominant Mie-type scatter present in tissue. Overall, this paper gives a comprehensive over view of the modeling techniques used in diffuse optical tomographic imaging, in the context of NIRFAST software package.
TL;DR: The reduced O2 cost of exercise following increased dietary nitrate intake has important implications for the understanding of the factors that regulate mitochondrial respiration and muscle contractile energetics in humans.
Abstract: Pharmacological sodium nitrate supplementation has been reported to reduce the O2 cost of submaximal exercise in humans. In this study, we hypothesized that dietary supplementation with inorganic n...
TL;DR: In this paper, the authors reported the discovery of very shallow (ΔF/F ≈ 3.4× 10 −4 ) periodic dips in the light curve of an active V = 11.7 G9V star observed by the CoRoT satellite, which they interpret as caused by a transiting companion.
Abstract: Aims. We report the discovery of very shallow (ΔF/F ≈ 3.4× 10 −4 ), periodic dips in the light curve of an active V = 11.7 G9V star observed by the CoRoT satellite, which we interpret as caused by a transiting companion. We describe the 3-colour CoRoT data and complementary ground-based observations that support the planetary nature of the companion. Methods. We used CoRoT colours information, good angular resolution ground-based photometric observations in- and out- of transit, adaptive optics imaging, near-infrared spectroscopy, and preliminary results from radial velocity measurements, to test the diluted eclipsing binary scenarios. The parameters of the host star were derived from optical spectra, which were then combined with the CoRoT light curve to derive parameters of the companion. Results. We examined all conceivable cases of false positives carefully, and all the tests support the planetary hypothesis. Blends with separation >0.40 �� or triple systems are almost excluded with a 8 × 10 −4 risk left. We conclude that, inasmuch we have been exhaustive, we have discovered a planetary companion, named CoRoT-7b, for which we derive a period of 0.853 59 ± 3 × 10 −5 day and a radius of Rp = 1.68 ± 0.09 REarth .A nalysis of preliminary radial velocity data yields an upper limit of 21 MEarth for the companion mass, supporting the finding. Conclusions. CoRoT-7b is very likely the first Super-Earth with a measured radius. This object illustrates what will probably become a common situation with missions such as Kepler, namely the need to establish the planetary origin of transits in the absence of a firm radial velocity detection and mass measurement. The composition of CoRoT-7b remains loosely constrained without a precise mass. A very high surface temperature on its irradiated face, ≈1800–2600 K at the substellar point, and a very low one, ≈50 K, on its dark face assuming no atmosphere, have been derived.
TL;DR: In this paper, a session-by-session outcome monitoring system achieved unusually high levels of pre-to-post-treatment data completeness, with low-intensity interventions (such as guided self-help) being particularly helpful for achieving high throughput.
Karolinska Institutet1, University of Pittsburgh2, Queen Mary University of London3, University of Exeter4, University of Texas Health Science Center at Houston5, University of St Andrews6, University of California, San Diego7, Aarhus University8, University of Warwick9, University of California, Santa Barbara10, University of Birmingham11, Yeshiva University12, University of Düsseldorf13, Louisiana State University in Shreveport14, Wake Forest University15, University of Vienna16, University of Alabama at Birmingham17, Emory University18, University of Glasgow19, Cleveland Clinic20, Uppsala University21, Russian Academy of Sciences22, University of Oklahoma23, National Institutes of Health24, University of Tokushima25, Utrecht University26, Ohio State University27
TL;DR: The latest advances in the understanding of the biochemistry, physiology and therapeutics of nitrate, nitrite and NO were discussed during a recent 2-day meeting at the Nobel Forum, Karolinska Institutet in Stockholm.
Abstract: Inorganic nitrate and nitrite from endogenous or dietary sources are metabolized in vivo to nitric oxide (NO) and other bioactive nitrogen oxides. The nitrate-nitrite-NO pathway is emerging as an important mediator of blood flow regulation, cell signaling, energetics and tissue responses to hypoxia. The latest advances in our understanding of the biochemistry, physiology and therapeutics of nitrate, nitrite and NO were discussed during a recent 2-day meeting at the Nobel Forum, Karolinska Institutet in Stockholm.
TL;DR: If ketones are present in blood or urine, treatment is urgent, because ketoacidosis can evolve rapidly.
Abstract: Diabetes mellitus is a group of metabolic diseases characterised by chronic hyperglycemia resulting from defects in insulin secretion, insulin action, or both. The abnormalities in carbohydrate, fat, and protein metabolism that are found in diabetes are due to deficient action of insulin on target tissues. If ketones are present in blood or urine, treatment is urgent, because ketoacidosis can evolve rapidly.
TL;DR: In this paper, two ideal types of researcher, one a criteriologist and the other a relativist, are constructed to illustrate how each might judge qualitative studies of different kinds.
TL;DR: In this paper, the authors report the statistical properties of stars, brown dwarfs and multiple systems obtained from the largest hydrodynamical simulation of star cluster formation to date that resolves masses down to the opacity limit for fragmentation (a few Jupiter masses).
Abstract: We report the statistical properties of stars, brown dwarfs and multiple systems obtained from the largest hydrodynamical simulation of star cluster formation to date that resolves masses down to the opacity limit for fragmentation (a few Jupiter masses). The simulation is essentially identical to that of Bate, Bonnell & Bromm except that the initial molecular cloud is larger and more massive. It produces more than 1250 stars and brown dwarfs, providing unprecedented statistical information that can be compared with observational surveys. The calculation uses sink particles to model the stars and brown dwarfs. Part of the calculation is rerun with smaller sink particle accretion radii and gravitational softening to investigate the effect of these approximations on the results. We find that hydrodynamical/sink particle simulations can reproduce many of the observed stellar properties very well. Multiplicity as a function of the primary mass, the frequency of very low mass (VLM) binaries, general trends for the separation and mass ratio distributions of binaries and the relative orbital orientations of triples systems are all in reasonable agreement with observations. We also examine the radial variations of binarity, velocity dispersion and mass function in the resulting stellar cluster and the distributions of disc truncation radii due to dynamical interactions. For VLM binaries, because their separations are typically close, we find that their frequency is sensitive to the sink particle accretion radii and gravitational softening used in the calculations. Using small accretion radii and gravitational softening results in a frequency of VLM binaries similar to that expected from observational surveys (≈20 per cent). We also find that VLM binaries evolve from wide, unequal-mass systems towards close equal-mass systems as they form. The two main deficiencies of the calculations are that they overproduce brown dwarfs relative to stars and that there are too few unequalmass binaries with K- and G-dwarf primaries. The former of these is likely due to the absence of radiative feedback and/or magnetic fields.
TL;DR: Three independent lines of evidence demonstrating domestication in the Eneolithic Botai Culture of Kazakhstan, dating to about 3500 B.C.E. are presented.
Abstract: Horse domestication revolutionized transport, communications, and warfare in prehistory, yet the identification of early domestication processes has been problematic. Here, we present three independent lines of evidence demonstrating domestication in the Eneolithic Botai Culture of Kazakhstan, dating to about 3500 B.C.E. Metrical analysis of horse metacarpals shows that Botai horses resemble Bronze Age domestic horses rather than Paleolithic wild horses from the same region. Pathological characteristics indicate that some Botai horses were bridled, perhaps ridden. Organic residue analysis, using delta13C and deltaD values of fatty acids, reveals processing of mare's milk and carcass products in ceramics, indicating a developed domestic economy encompassing secondary products.
TL;DR: In this article, the authors compare the carbon emissions of a large-scale vegetable box distribution system and a local farm shop distribution system using fuel and energy use data collected from one of the UK's largest suppliers of organic produce and find that if a customer drives a round-trip distance of more than 6.7 km in order to purchase their organic vegetables, their carbon emissions are likely to be greater than the emissions from the system of cold storage, packing, transport to a regional hub and final transport to customer's doorstep used by large scale vegetable box suppliers.
TL;DR: The identification of a GCK mutation in patients with both hyper‐ and hypoglycemia has implications for the clinical course and clinical management of their disorder.
Abstract: Glucokinase is a key regulatory enzyme in the pancreatic beta-cell. It plays a crucial role in the regulation of insulin secretion and has been termed the glucose sensor in pancreatic beta-cells. Given its central role in the regulation of insulin release it is understandable that mutations in the gene encoding glucokinase (GCK) can cause both hyper- and hypoglycemia. Heterozygous inactivating mutations in GCK cause maturity-onset diabetes of the young (MODY) subtype glucokinase (GCK), characterized by mild fasting hyperglycemia, which is present at birth but often only detected later in life during screening for other purposes. Homozygous inactivating GCK mutations result in a more severe phenotype presenting at birth as permanent neonatal diabetes mellitus (PNDM). A growing number of heterozygous activating GCK mutations that cause hypoglycemia have also been reported. A total of 620 mutations in the GCK gene have been described in a total of 1,441 families. There are no common mutations, and the mutations are distributed throughout the gene. The majority of activating mutations cluster in a discrete region of the protein termed the allosteric activator site. The identification of a GCK mutation in patients with both hyper- and hypoglycemia has implications for the clinical course and clinical management of their disorder.
TL;DR: In this paper, the state of the art in NTE solids is reviewed, and understanding of the driving mechanisms of the effect is considered along with experimental and theoretical evidence, and various categories of solids with NTE are explored, and experimental methods for their experimental characterisation and applications for such solids are proposed.
Abstract: Most materials demonstrate an expansion upon heating, however a few are known to contract, i.e. exhibit a negative coefficient of thermal expansivity (NTE). This naturally occurring phenomenon has been shown to occur in a range of solids including complex metal oxides, polymers and zeolites, and opens the door to composites with a coefficient of thermal expansion (CTE) of zero. The state of the art in NTE solids is reviewed, and understanding of the driving mechanisms of the effect is considered along with experimental and theoretical evidence. The various categories of solids with NTE are explored, and experimental methods for their experimental characterisation and applications for such solids are proposed. An abstraction for an underlying mechanism for NTE at the supramolecular level and its applicability at the molecular level is discussed.
TL;DR: In this paper, the authors suggest that if appropriately managed and designed, MREI may increase local biodiversity and potentially benefit the wider marine environment, and they suggest that conflicts should be minimized by integrating key stakeholders into the design, siting, construction and operational phases of the installations, and by providing clear evidence of their potential environmental benefits.
Abstract: Summary
1. The evidence for anthropogenically induced climate change is overwhelming with the production of greenhouse gases from burning fossil fuels being a key driver. In response, many governments have initiated programmes of energy production from renewable sources.
2. The marine environment presents a relatively untapped energy source and offshore installations are likely to produce a significant proportion of future energy production. Wind power is the most advanced, with development of wave and tidal energy conversion devices expected to increase worldwide in the near future.
3. Concerns over the potential impacts on biodiversity of marine renewable energy installations (MREI) include: habitat loss, collision risks, noise and electromagnetic fields. These factors have been posited as having potentially important negative environmental impacts.
4. Conversely, we suggest that if appropriately managed and designed, MREI may increase local biodiversity and potentially benefit the wider marine environment. Installations have the capacity to act as both artificial reefs and fish aggregation devices, which have been used previously to facilitate restoration of damaged ecosystems, and de facto marine-protected areas, which have proven successful in enhancing both biodiversity and fisheries.
5. The deployment of MREI has the potential to cause conflict among interest groups including energy companies, the fishing sector and environmental groups. Conflicts should be minimized by integrating key stakeholders into the design, siting, construction and operational phases of the installations, and by providing clear evidence of their potential environmental benefits.
6. Synthesis and applications. MREI have the potential to be both detrimental and beneficial to the environment but the evidence base remains limited. To allow for full biodiversity impacts to be assessed, there exists an urgent need for additional multi and inter-disciplinary research in this area ranging from engineering to policy. Whilst there are a number of factors to be considered, one of the key decisions facing current policy makers is where installations should be sited, and, dependent upon site, whether they should be designed to either minimize negative environmental impacts or as facilitators of ecosystem restoration.
TL;DR: A better understanding of cross-talk between hormonal and defense signaling pathways should reveal new potential targets for microbial effectors that attenuate host resistance mechanisms.
Abstract: Diseased plants often display phenotypes consistent with hormone perturbations. We review recent data that have revealed roles in plant-microbe interactions for cellular components and signaling molecules that previously were associated only with hormone signaling. A better understanding of cross-talk between hormonal and defense signaling pathways should reveal new potential targets for microbial effectors that attenuate host resistance mechanisms.
TL;DR: In this paper, the authors suggest that unreasonable experimental effectiveness arises from natural scale independence, and they advocate a shift in emphasis in experimental stratigraphy and geomorphology away from classical dynamical scaling and towards a quantitative understanding of the origins and limits of scale independence.
TL;DR: In this paper, the authors present a review of knowledge management and knowledge transfer in the context of innovations in tourism, focusing on the integration of management perspectives into tourism research and highlighting the need to give closer attention to the nature of innovations within tourism and to consider these in a knowledge management framework.
TL;DR: There was support for the social identity approach to attitude-behaviour relations in that group norms predicted recycling intentions, particularly for individuals who identified strongly with the group.
Abstract: The present research investigated three approaches to the role of norms in the theory of planned behaviour (TPB). Two studies examined the proposed predictors of intentions to engage in household recycling (Studies 1 and 2) and reported recycling behaviour (Study 1). Study 1 tested the impact of descriptive and injunctive norms (personal and social) and the moderating role of self-monitoring on norm-intention relations. Study 2 examined the role of group norms and group identification and the moderating role of collective self on norm-intention relations. Both studies demonstrated support for the TPB and the inclusion of additional normative variables: attitudes; perceived behavioural control; descriptive; and personal injunctive norms (but not social injunctive norm) emerged as significant independent predictors of intentions. There was no evidence that the impact of norms on intentions varied as a function of the dispositional variables of self-monitoring (Study 1) or the collective self (Study 2). There was support, however, for the social identity approach to attitude-behaviour relations in that group norms predicted recycling intentions, particularly for individuals who identified strongly with the group. The results of these two studies highlight the critical role of social influence processes within the TPB and the attitude-behaviour context.
TL;DR: This article reviewed the data from peer-reviewed publications to assess the likely impacts of climate change on marine turtles and highlight the types of data that would be most useful for an accurate assessment of future effects.
Abstract: Marine turtles occupy a wide range of terrestrial and marine habitats, and many aspects of their life history have been demonstrated to be closely tied to climatic variables such as ambient temperature and storminess. As a group, therefore, marine turtles may be good indicators of climate change effects on coastal and marine habitats. Despite the small number of species in the taxon and a growing body of research in the field, the evidence base to predict resultant impacts of climate change remains relatively poor. We review the data from peer-reviewed publications to assess the likely impacts of climate change on marine turtles and highlight the types of data that would be most useful for an accurate assessment of future effects. The cumulative indications from these previous studies indicate that future research should focus on: (1) climate change effects on key habitats upon which turtles depend; (2) factors that influence nest site selection; (3) the consequences of skewed primary sex ratios; and (4) the effect of climate change on turtles at sea, for example range shifts and dietary breadth. Although it is too early to give detailed management recommendations, careful protection of coastlines along which turtles nest should be considered, as should the protection of beaches that produce male hatchlings, which may be of increased importance in the future. More active management approaches, for example translocation of eggs to suitable yet vacant nesting beaches, may be necessary to consider under worst-case scenarios.
TL;DR: The planet has an equilibrium temperature of T eq = 2516 K caused by its very short period orbit around the hot, twelfth magnitude host star and has the largest radius of any transiting planet yet detected.
Abstract: We report on the discovery of WASP-12b, a new transiting extrasolar planet with R pl = 1.79+0.09 –0.09 RJ and M pl = 1.41+0.10 –0.10 M J. The planet and host star properties were derived from a Monte Carlo Markov Chain analysis of the transit photometry and radial velocity data. Furthermore, by comparing the stellar spectrum with theoretical spectra and stellar evolution models, we determined that the host star is a supersolar metallicity ([M/H] = 0.3+0.05 –0.15), late-F (T eff = 6300+200 –100 K) star which is evolving off the zero-age main sequence. The planet has an equilibrium temperature of T eq = 2516 K caused by its very short period orbit (P = 1.09 days) around the hot, twelfth magnitude host star. WASP-12b has the largest radius of any transiting planet yet detected. It is also the most heavily irradiated and the shortest period planet in the literature.
TL;DR: It is found that male–male competition and female mate choice can be reinforcing or opposing, although the former is most common in the literature, and the mechanisms of sexual selection are more likely to be opposing when the mechanisms operated sequentially.
Abstract: Empirical studies of sexual selection typically focus on one of the two mechanisms of sexual selection without integrating these into a description of total sexual selection, or study total sexual selection without quantifying the contributions of all of the mechanisms of sexual selection. However, this can provide an incomplete or misleading view of how sexually selected traits evolve if the mechanisms of sexual selection are opposing or differ in form. Here, we take a two-fold approach to advocate a direction for future studies of sexual selection. We first show how a quantitative partitioning and examination of sexual selection mechanisms can inform by identifying illustrative studies that describe both male-male competition and female mate choice acting on the same trait. In our sample, the most common trait where this occurred was body size, and selection was typically linear. We found that male-male competition and female mate choice can be reinforcing or opposing, although the former is most common in the literature. The mechanisms of sexual selection can occur simultaneously or sequentially, and we found they were more likely to be opposing when the mechanisms operated sequentially. The degree and timing that these mechanisms interact have important implications for the operation of sexual selection and needs to be considered in designing studies. Our examples highlight where empirical data are needed. We especially lack standardized measures of the form and strength of selection imposed by each mechanism of sexual selection and how they combine to determine total sexual selection. Secondly, using quantitative genetic principles, we outline how the selection imposed by individual mechanisms can be measured and combined to estimate the total strength and form of sexual selection. We discuss the evolutionary consequences of combining the mechanisms of sexual selection and interpreting total sexual selection. We suggest how this approach may result in empirical progress in the field of sexual selection.