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Showing papers by "Queen's University Belfast published in 2004"


Journal ArticleDOI
TL;DR: In this paper, a new calibration curve for the conversion of radiocarbon ages to calibrated (cal) ages has been constructed and internationally ratified to replace IntCal98, which extended from 0-24 cal kyr BP (Before Present, 0 cal BP = AD 1950).
Abstract: A new calibration curve for the conversion of radiocarbon ages to calibrated (cal) ages has been constructed and internationally ratified to replace IntCal98, which extended from 0-24 cal kyr BP (Before Present, 0 cal BP = AD 1950). The new calibration data set for terrestrial samples extends from 0-26 cal kyr BP, but with much higher resolution beyond 11.4 cal kyr BP than IntCal98. Dendrochronologically-dated tree-ring samples cover the period from 0-12.4 cal kyr BP. Beyond the end of the tree rings, data from marine records (corals and foraminifera) are converted to the atmospheric equivalent with a site-specific marine reservoir correction to provide terrestrial calibration from 12.4-26.0 cal kyr BP. A substantial enhancement relative to IntCal98 is the introduction of a coherent statistical approach based on a random walk model, which takes into account the uncertainty in both the calendar age and the 14C age to calculate the underlying calibration curve (Buck and Blackwell, this issue). The tree-ring data sets, sources of uncertainty, and regional offsets are discussed here. The marine data sets and calibration curve for marine samples from the surface mixed layer (Marine04) are discussed in brief, but details are presented in Hughen et al. (this issue a). We do not make a recommendation for calibration beyond 26 cal kyr BP at this time; however, potential calibration data sets are compared in another paper (van der Plicht et al., this issue).

3,737 citations


Journal ArticleDOI
TL;DR: In this paper, a new radiocarbon calibration curve, IntCal04 and Marine04, has been constructed and internationally rati- fied to replace the terrestrial and marine components of IntCal98.
Abstract: New radiocarbon calibration curves, IntCal04 and Marine04, have been constructed and internationally rati- fied to replace the terrestrial and marine components of IntCal98. The new calibration data sets extend an additional 2000 yr, from 0-26 cal kyr BP (Before Present, 0 cal BP = AD 1950), and provide much higher resolution, greater precision, and more detailed structure than IntCal98. For the Marine04 curve, dendrochronologically-dated tree-ring samples, converted with a box diffusion model to marine mixed-layer ages, cover the period from 0-10.5 cal kyr BP. Beyond 10.5 cal kyr BP, high-res- olution marine data become available from foraminifera in varved sediments and U/Th-dated corals. The marine records are corrected with site-specific 14C reservoir age information to provide a single global marine mixed-layer calibration from 10.5-26.0 cal kyr BP. A substantial enhancement relative to IntCal98 is the introduction of a random walk model, which takes into account the uncertainty in both the calendar age and the 14C age to calculate the underlying calibration curve (Buck and Blackwell, this issue). The marine data sets and calibration curve for marine samples from the surface mixed layer (Marine04) are discussed here. The tree-ring data sets, sources of uncertainty, and regional offsets are presented in detail in a companion paper by Reimer et al. (this issue). ABSTRACT. New radiocarbon calibration curves, IntCal04 and Marine04, have been constructed and internationally rati- fied to replace the terrestrial and marine components of IntCal98. The new calibration data sets extend an additional 2000 yr, from 0-26 cal kyr BP (Before Present, 0 cal BP = AD 1950), and provide much higher resolution, greater precision, and more detailed structure than IntCal98. For the Marine04 curve, dendrochronologically-dated tree-ring samples, converted with a box diffusion model to marine mixed-layer ages, cover the period from 0-10.5 cal kyr BP. Beyond 10.5 cal kyr BP, high-res- olution marine data become available from foraminifera in varved sediments and U/Th-dated corals. The marine records are corrected with site-specific 14C reservoir age information to provide a single global marine mixed-layer calibration from 10.5-26.0 cal kyr BP. A substantial enhancement relative to IntCal98 is the introduction of a random walk model, which takes into account the uncertainty in both the calendar age and the 14C age to calculate the underlying calibration curve (Buck and Blackwell, this issue). The marine data sets and calibration curve for marine samples from the surface mixed layer (Marine04) are discussed here. The tree-ring data sets, sources of uncertainty, and regional offsets are presented in detail in a companion paper by Reimer et al. (this issue).

1,205 citations


Journal ArticleDOI
TL;DR: This approach is a potentially powerful method of measuring trophic niche width, particularly if combined with conventional approaches, because it provides a single measure on a continuous axis that is common to all species; it integrates information on only assimilated prey over time; and data production is theoretically fast and testing among populations simple.
Abstract: 1. Although conceptually robust, it has proven difficult to find practical measures of niche width that are simple to obtain, yet provide an adequate descriptor of the ecological position of the population examined. 2. Trophic niche has proven more tractable than other niche dimensions. However, indices used as a proxy for trophic niche width often suffer from the following difficulties. Such indices rarely lie along a single scale making comparisons between populations or species difficult; have difficulty in combining dietary prey diversity and evenness in an ecologically meaningful way; and fail to integrate diet over ecological time-scales thus usually only comprise single snapshots of niche width. 3. We propose an alternative novel method for the comparison of trophic niche width: the use of variance of tissue stable isotope ratios, especially those of nitrogen and carbon. 4. This approach is a potentially powerful method of measuring trophic niche width, particularly if combined with conventional approaches, because: it provides a single measure on a continuous axis that is common to all species; it integrates information on only assimilated prey over time; the integration period changes with choice of tissue sampled; and data production is theoretically fast and testing among populations simple. 5. Empirical studies are now required to test the benefits of using isotopic variance as a measure of niche width, and in doing so help refine this approach.

1,171 citations


Journal ArticleDOI
TL;DR: An intense laser-plasma interaction regime of the generation of high density ultrashort relativistic ion beams is suggested and it is suggested that the laser energy is transformed efficiently into the energy of fast ions.
Abstract: An intense laser-plasma interaction regime of the generation of high density ultrashort relativistic ion beams is suggested. When the radiation pressure is dominant, the laser energy is transformed efficiently into the energy of fast ions.

951 citations


Journal ArticleDOI
TL;DR: The descriptive epidemiology of the disease is reviewed, focusing on some of the key elements of the geographical and temporal variations in incidence and mortality in each world region, in the context of the numerous aetiological factors.
Abstract: One in ten of all new cancers diagnosed worldwide each year is a cancer of the female breast, and it is the most common cancer in women in both developing and developed areas. It is also the principal cause of death from cancer among women globally. We review the descriptive epidemiology of the disease, focusing on some of the key elements of the geographical and temporal variations in incidence and mortality in each world region. The observations are discussed in the context of the numerous aetiological factors, as well as the impact of screening and advances in treatment and disease management in high-resource settings.

946 citations


Journal ArticleDOI
TL;DR: An extended Langmuir model has been used to predict the isotherm data for the binary systems using the single component data, and the linear transform model provided the highest R(2) regression coefficient with the Redlich-Peterson model.

931 citations


Journal ArticleDOI
TL;DR: In this article, the authors unpack the heterogeneity of interests and preferences across and within types of shareholders and senior managers over time in an analysis of the adoption of a shareholder value orientation among contemporary German firms.
Abstract: This study offers a sociopolitical perspective on the international spread of corporate governance models. We unpack the heterogeneity of interests and preferences across and within types of shareholders and senior managers over time in an analysis of the adoption of a shareholder value orientation among contemporary German firms. Using extensive data on more than 100 of the largest publicly traded German companies from 1990 to 2000, we find that the influence of major shareholder groups (e.g., banks, industrial corporations, governments, and families) and senior manager types (differing educational backgrounds and ages) can be clearly observed only after redefining these key actors according to common interests and preferences. We also find evidence that German firms engage in decoupling by espousing but not implementing a shareholder value orientation but show that the presence of more powerful and more committed key actors reduces the likelihood of decoupling. We discuss the implications of our finding...

802 citations


Journal ArticleDOI
TL;DR: Some of the recent findings on resistance mechanisms are summarized, some recommendations for limiting its impact are put forward and some priorities for research in this area are suggested.

799 citations


Journal ArticleDOI
TL;DR: In this article, the use of fraction modern with a new symbol F{sup 14}C to prevent confusion with the previously used Fm, which may or may not have been fractionation corrected.
Abstract: The definitive paper by Stuiver and Polach (1977) established the conventions for reporting of {sup 14}C data for chronological and geophysical studies based on the radioactive decay of {sup 14}C in the sample since the year of sample death or formation. Several ways of reporting {sup 14}C activity levels relative to a standard were also established, but no specific instructions were given for reporting nuclear weapons testing (post-bomb) {sup 14}C levels in samples. Because the use of post-bomb {sup 14}C is becoming more prevalent in forensics, biology, and geosciences, a convention needs to be adopted. We advocate the use of fraction modern with a new symbol F{sup 14}C to prevent confusion with the previously used Fm, which may or may not have been fractionation corrected. We also discuss the calibration of post-bomb {sup 14}C samples and the available datasets and compilations, but do not give a recommendation for a particular dataset.

640 citations


Journal ArticleDOI
TL;DR: To design a new, highly sensitive psychometric screening to identify patients with mild cognitive impairment (MCI) and patients with dementia in the early stages of the disease.
Abstract: Objectives To design a new, highly sensitive psychometric screening to identify patients with mild cognitive impairment (MCI) and patients with dementia in the early stages of the disease. Methods Five tasks were included in the DemTect: a word list, a number transcoding task, a word fluency task, digit span reverse, and delayed recall of the word list. The normation was performed with 145 healthy control subjects (CG). Furthermore, 97 MCI patients and 121 patients with possible Alzheimer's disease (AD) were tested with the DemTect and the MMSE. Classification rates for both tests were analysed. Results On the basis of the CG data, age-dependant transformation algorithms for the DemTect subtests were defined, and an education correction was provided for the total transformed score. The patient groups scored significantly below the CG in both the DemTect and the MMSE. Compared to the MMSE, classification rates of the DemTect were superior for both the MCI and the AD group, with high sensitivities of 80% and 100%, respectively. Conclusions The DemTect is short (8–10 minutes), easy to administer, and its transformed total score (maximum 18) is independent of age and education. The DemTect helps in deciding whether cognitive performance is adequate for age (13–18 points), or whether MCI (9–12 points) or dementia (8 points or below) should be suspected. Copyright © 2004 John Wiley & Sons, Ltd.

626 citations


Journal ArticleDOI
TL;DR: Currently available approaches to molecular-scale logic gates are summarized and compared and integration of simple logic functions to produce more complex ones is discussed in terms of recent developments.
Abstract: Currently available approaches to molecular-scale logic gates are summarized and compared. These include: chemically-controlled fluorescent and transmittance-based switches concerned with small molecules, DNA oligonucleotides with fluorescence readout, oligonucleotide reactions with DNA-based catalysts, chemically-gated photochromics, reversibly denaturable proteins, molecular machines with optical and electronic signals, two-photon fluorophores and multichromophoric transient optical switches. The photochemical principles of electron and energy transfer are involved in several of these approaches. More complex molecular logic systems with reconfigurability and superposability provide contrasts with current semiconductor electronics. Integration of simple logic functions to produce more complex ones is also discussed in terms of recent developments.

Journal ArticleDOI
01 Nov 2004-Diabetes
TL;DR: A more general association of the PTPN22 locus with autoimmune disease is indicated, as reported for an association of Trp(620) with another autoimmune disorder, Graves' disease, in 1,734 case and control subjects.
Abstract: In the genetic analysis of common, multifactorial diseases, such as type 1 diabetes, true positive irrefutable linkage and association results have been rare to date. Recently, it has been reported that a single nucleotide polymorphism (SNP), 1858C>T, in the gene PTPN22, encoding Arg620Trp in the lymphoid protein tyrosine phosphatase (LYP), which has been shown to be a negative regulator of T-cell activation, is associated with an increased risk of type 1 diabetes. Here, we have replicated these findings in 1,388 type 1 diabetic families and in a collection of 1,599 case and 1,718 control subjects, confirming the association of the PTPN22 locus with type 1 diabetes (family-based relative risk (RR) 1.67 [95% CI 1.46-1.91], and case-control odds ratio (OR) 1.78 [95% CI 1.54-2.06]; overall P = 6.02 x 10(-27)). We also report evidence for an association of Trp(620) with another autoimmune disorder, Graves' disease, in 1,734 case and control subjects (P = 6.24 x 10(-4); OR 1.43 [95% CI 1.17-1.76]). Taken together, these results indicate a more general association of the PTPN22 locus with autoimmune disease.

Journal ArticleDOI
TL;DR: It is shown that the influence of parasitism on the outcomes of animal invasions is more subtle and wide ranging than has been previously realized.
Abstract: Biological invasions are global threats to biodiversity and parasites might play a role in determining invasion outcomes. Transmission of parasites from invading to native species can occur, aiding the invasion process, whilst the 'release' of invaders from parasites can also facilitate invasions. Parasites might also have indirect effects on the outcomes of invasions by mediating a range of competitive and predatory interactions among native and invading species. Although pathogen outbreaks can cause catastrophic species loss with knock-on effects for community structure, it is less clear what impact persistent, sub-lethal parasitism has on native-invader interactions and community structure. Here, we show that the influence of parasitism on the outcomes of animal invasions is more subtle and wide ranging than has been previously realized.

Journal ArticleDOI
TL;DR: There was little evidence to suggest that the addition of ice to compression had any significant effect, but this was restricted to treatment of hospital inpatients and there was no evidence of an optimal mode or duration of treatment.
Abstract: Background: There are wide variations in the clinical use of cryotherapy, and guidelines continue to be made on an empirical basis.Study Design: Systematic review assessing the evidence base for cryotherapy in the treatment of acute soft-tissue injuries.Methods: A computerized literature search, citation tracking, and hand searching were carried out up to April 2002. Eligible studies were randomized-controlled trials describing human subjects recovering from acute soft-tissue injuries and employing a cryotherapy treatment in isolation or in combination with other therapies. Two reviewers independently assessed the validity of included trials using the Physiotherapy Evidence Database (PEDro) scale.Results: Twenty-two trials met the inclusion criteria. There was a mean PEDro score of 3.4 out of of 10. There was marginal evidence that ice plus exercise is most effective, after ankle sprain and postsurgery. There was little evidence to suggest that the addition of ice to compression had any significant effect...

Journal ArticleDOI
TL;DR: It is concluded that a loss of BRCA1 function is associated with sensitivity to DNA-damaging chemotherapy and may also be associated with resistance to spindle poisons.
Abstract: Germline mutations of the BRCA1 gene account for approximately 5% of breast and ovarian cancer cases, and lower than normal BRCA1 expression or function may be an important contributing factor in sporadic cancers. The major role of BRCA1 is to respond to DNA damage by participating in cellular pathways for DNA repair, mRNA transcription, cell cycle regulation, and protein ubiquitination. Because most chemotherapeutic agents function by directly or indirectly damaging DNA, the role of BRCA1 as a regulator of chemotherapy-induced DNA damage has been the subject of an increasing number of investigations. We review published preclinical and clinical evidence that the level of BRCA1 function in an individual patient's tumor can guide the choice of chemotherapeutic agents for breast and ovarian cancer. We conclude that a loss of BRCA1 function is associated with sensitivity to DNA-damaging chemotherapy and may also be associated with resistance to spindle poisons. We recommend that prospective clinical studies investigating the role of BRCA1 in the response to chemotherapy be conducted.

Journal ArticleDOI
TL;DR: Laroscopic excision of endometriosis is more effective than placebo at reducing pain and improving quality of life, and surgery is associated with a 30% placebo response rate that is not dependent on severity of disease.

Journal ArticleDOI
TL;DR: An electronically polarizable model for the ionic liquid 1-ethyl-3methylimidazolium nitrate (EMIM+/NO3-) was developed in this paper.
Abstract: An electronically polarizable model has been developed for the ionic liquid 1-ethyl-3-methylimidazolium nitrate (EMIM+/NO3-). Molecular dynamics simulation studies were then performed on both the polarizable and nonpolarizable versions of the model. Comparisons of shear viscosity and diffusion constants at 400 K show that the effects of polarizability are quite substantial and the polarizable model results are in better agreement with the experimental values.

Journal ArticleDOI
TL;DR: In this article, the authors used a gravimetric technique to determine the sorption and desorption isotherms for potato, highly amylopectin, and high amylose starch powders at 30, 45 and 60 °C.


Journal ArticleDOI
TL;DR: In this article, the effect of heterogeneity, modification and diatomite frustule type on adsorption was investigated for heavy metal removal from wastewater using both centric and pennate types of diatomites.

Journal ArticleDOI
TL;DR: In this paper, a glasshouse pot experiment and a laboratory leaching column experiment were conducted to study the EDTA enhancement of the mobility and phyto-extraction of heavy metals and the potential for leaching of metals during the phyttoextraction process.

Journal ArticleDOI
04 Nov 2004-Nature
TL;DR: Fears about environmental threats to human health have centred on the possible induction of cancers, but risks to the male germ line, both real and potential, are also causing disquiet.
Abstract: During the past few decades, worries about environmental threats to human health have centred on the possible induction of cancers. Now risks to the male germ line, both real and potential, are also causing disquiet.

Journal ArticleDOI
TL;DR: Although Karl Mannheim and Ernst Bloch provide two contrasting analyses of the relationship between ideology and utopia, they hold in common the belief that the two concepts need to be examined together as a pair of closely related concepts as discussed by the authors.
Abstract: Although Karl Mannheim and Ernst Bloch provide two contrasting analyses of the relationship between ideology and utopia, they hold in common the belief that the two concepts need to be examined together as a pair of closely related concepts. Mannheim argues that the ideological and the utopian are both forms of ‘reality‐transcendence’, and constructs an historical account of their role in the emergence of modernity. Bloch posits a ‘utopian surplus’ in ideology which carries the ‘not‐yet’ of human potential. The recent ‘post‐secular’ turn in contemporary political philosophy provides an excellent focus for considering the utility of the two approaches, and a discussion of the relationship of the two thinkers to the work of Karl Marx can help clarify the nature of their differences.

Journal ArticleDOI
David P. Schmitt1, Lidia Alcalay2, Melissa Allensworth1, Jüri Allik3, Lara Ault4, Ivars Austers5, Kevin Bennett6, Gabriel Bianchi7, Fredrick Boholst8, Mary Ann Borg Cunen9, Johan Braeckman10, Edwin G. Brainerd11, Leo Gerard A. Caral8, Gabrielle Caron, María Martina Casullo12, Michael Cunningham4, Ikuo Daibo13, Charlotte J. S. De Backer10, Eros De Souza14, Rolando Díaz-Loving15, Glaucia Ribeiro Starling Diniz16, Kevin Durkin17, Marcela Echegaray18, Ekin Eremsoy19, Harald A. Euler20, Ruth Falzon9, Maryanne L. Fisher21, Dolores Foley22, Robert Fowler1, Douglas P. Fry23, Sirpa Fry23, M. Arif Ghayur24, Vijai N. Giri25, Debra L. Golden26, Karl Grammer, Liria Grimaldi27, Jamin Halberstadt28, Shamsul Haque29, Dora Herrera18, Janine Hertel30, Amanda Hitchell1, Heather Hoffmann31, Danica Hooper22, Zuzana Hradilekova32, Jasna Hudek-Kene-Evi33, Allen I. Huffcutt1, Jas Laile Suzana Binti Jaafar34, Margarita Jankauskaite35, Heidi Kabangu-Stahel, Igor Kardum33, Brigitte Khoury36, Hayrran Kwon37, Kaia Laidra3, Anton Laireiter38, Dustin Lakerveld39, Ada Lampert, Mary Anne Lauri9, Marguerite Lavallée, Suk-Jae Lee40, Luk Chung Leung41, Kenneth D. Locke42, Vance Locke17, Ivan Lukšík7, Ishmael Magaisa43, Dalia Marcinkeviciene35, André Mata44, Rui Mata44, Barry Mccarthy45, Michael E. Mills46, Nhlanhla Mkhize47, João Manuel Moreira44, Sérgio Moreira44, Miguel Moya48, M. Munyae49, Patricia Noller22, Hmoud Olimat50, Adrian Opre51, Alexia Panayiotou52, Nebojša Petrović53, Karolien Poels10, Miroslav Popper7, Maria Poulimenou54, Volodymyr P'Yatokha, Michel Raymond55, Ulf-Dietrich Reips56, Susan E. Reneau57, Sofía Rivera-Aragón15, Wade C. Rowatt58, Willibald Ruch59, Velko S. Rus60, Marilyn P. Safir61, Sonia Salas62, Fabio Sambataro27, Kenneth Sandnabba23, Rachel Schleeter1, Marion K. Schulmeyer, Astrid Schütz30, Tullio Scrimali27, Todd K. Shackelford63, Mithila B. Sharan25, Phillip R. Shaver64, Francis J Sichona65, Franco Simonetti2, Tilahun Sineshaw66, R. Sookdew47, Tom Speelman10, Spyros Spyrou67, H. Canan Sümer, Nebi Sümer68, Marianna Supekova7, Tomasz Szlendak, Robin Taylor69, Bert Timmermans70, William Tooke71, Ioannis Tsaousis72, F. S.K. Tungaraza65, Ashley Turner1, Griet Vandermassen10, Tim Vanhoomissen73, Frank Van Overwalle73, Ine Vanwesenbeeck, Paul L. Vasey74, João Veríssimo44, Martin Voracek75, Wendy W.N. Wan76, Ta-Wei Wang77, Peter Weiss78, Andik Wijaya, Liesbeth Woertman39, Gahyun Youn79, Agata Zupanèiè60 
Bradley University1, Pontifical Catholic University of Chile2, University of Tartu3, University of Louisville4, University of Latvia5, University of New Mexico6, Slovak Academy of Sciences7, University of San Carlos8, University of Malta9, Ghent University10, Clemson University11, University of Buenos Aires12, Osaka University13, Illinois State University14, National Autonomous University of Mexico15, University of Brasília16, University of Western Australia17, University of Lima18, Boğaziçi University19, University of Kassel20, University of York21, University of Queensland22, Åbo Akademi University23, Al Akhawayn University24, Indian Institute of Technology Kharagpur25, University of Hawaii at Manoa26, University of Catania27, University of Otago28, University of Dhaka29, Chemnitz University of Technology30, Knox College31, Comenius University in Bratislava32, University of Rijeka33, University of Malaya34, Vilnius University35, American University of Beirut36, Kwangju Health College37, University of Salzburg38, Utrecht University39, National Computerization Agency40, City University of Hong Kong41, University of Idaho42, University of Zimbabwe43, University of Lisbon44, University of Central Lancashire45, Loyola Marymount University46, University of Natal47, University of Granada48, University of Botswana49, University of Jordan50, Babeș-Bolyai University51, University of Cyprus52, University of Belgrade53, KPMG54, University of Montpellier55, University of Zurich56, University of Alabama57, Baylor University58, Queen's University Belfast59, University of Ljubljana60, University of Haifa61, University of La Serena62, Florida Atlantic University63, University of California, Davis64, University of Dar es Salaam65, Ramapo College66, Cyprus College67, Middle East Technical University68, University of the South Pacific69, VU University Amsterdam70, State University of New York System71, University of the Aegean72, Vrije Universiteit Brussel73, University of Lethbridge74, University of Vienna75, University of Hong Kong76, Yuan Ze University77, Charles University in Prague78, Chonnam National University79
TL;DR: In the International Sexuality Description Project, a total of 17,804 participants from 62 cultural regions completed the RelationshipQuestionnaire (RQ), a self-report measure of adult romantic attachment as discussed by the authors.
Abstract: As part of the International Sexuality Description Project, a total of 17,804 participants from 62 cultural regions completedthe RelationshipQuestionnaire(RQ), a self-reportmeasure of adult romanticattachment. Correlational analyses within each culture suggested that the Model of Self and the Model of Other scales of the RQ were psychometrically valid within most cultures. Contrary to expectations, the Model of Self and Model of Other dimensions of the RQ did not underlie the four-category model of attachment in the same way across all cultures. Analyses of specific attachment styles revealed that secure romantic attachment was normative in 79% of cultures and that preoccupied romantic attachment was particularly prevalent in East Asian cultures. Finally, the romantic attachment profiles of individual nations were correlated with sociocultural indicators in ways that supported evolutionary theories of romantic attachment and basic human mating strategies.

Journal ArticleDOI
TL;DR: A general polymeric design of fluorescent logic gates, for example, AND, is illustrated, using temperature and pH as inputs.
Abstract: We illustrate a general polymeric design of fluorescent logic gates, for example, AND, using temperature and pH as inputs.

Journal ArticleDOI
TL;DR: It is posited that septins can act as regulatable scaffolds where the stoichiometry of septin associations, modifications, GTP status, and the interactions with other proteins allow the regulation of key cellular processes including polarity determination.
Abstract: Septins are an evolutionarily conserved group of GTP-binding and filament-forming proteins that belong to the large superclass of P-loop GTPases. While originally discovered in yeast as cell division cycle mutants with cytokinesis defects, they are now known to have diverse cellular roles which include polarity determination, cytoskeletal reorganization, membrane dynamics, vesicle trafficking, and exocytosis. Septin proteins form homo- and hetero-oligomeric polymers which can assemble into higher-order filaments. They are also known to interact with components of the cytoskeleton, ie actin and tubulin. The precise role of GTP binding is not clear but a current model suggests that it is associated with conformational changes which alter binding to other proteins. There are at least 12 human septin genes, and although information on expression patterns is limited, most undergo complex alternative splicing with some degree of tissue specificity. Nevertheless, an increasing body of data implicates the septin family in the pathogenesis of diverse disease states including neoplasia, neurodegenerative conditions, and infections. Here the known biochemical properties of mammalian septins are reviewed in the light of the data from yeast and other model organisms. The data implicating septins in human disease are considered and a model linking these data is proposed. It is posited that septins can act as regulatable scaffolds where the stoichiometry of septin associations, modifications, GTP status, and the interactions with other proteins allow the regulation of key cellular processes including polarity determination. Derangements of such septin scaffolds thus explain the role of septins in disease states.

Journal ArticleDOI
TL;DR: The role of the patient (irrespective of age) is critical in decision-making about medication, together with communication between patients and healthcare professionals, through the concept of concordance.
Abstract: Adherence to medication is one of the most intriguing and complex behaviours demonstrated by patients. Non-adherence to a therapeutic regimen may result in negative outcomes for patients and may be compounded in populations with multiple morbidities which require multiple drug therapy. Such a population is exemplified by the elderly. However, non-adherence may not be more prevalent in older patients and there is no consensus in the literature that age is a predictor of poor adherence. Indeed, older patients may deliberately choose not to adhere to medication (intentional non-adherence) to avoid adverse effects. Furthermore, many of the studies on adherence lack commonality in terms of how adherence is measured, the definition of an 'older' patient and the range of disease states which have been examined. Adherence may also be affected by access to medications which may be restricted by the use of formularies or insurance programmes. However, non-adherence may represent a greater risk in older people resulting in poor disease control which may be compounded with multiple morbidity and polypharmacy. A range of strategies have been implemented to try and improve adherence in this patient population. The use of forgiving drugs (those which have a prescribed dosage interval that is 50% or less the duration of drug action) may facilitate occasional lapses in drug-taking. Drug holidays (deliberate, supervised non-adherence for a fixed period of time) have been used in Parkinson's disease to reduce adverse effects. Once-daily scheduling of drug administration may offer a pragmatic approach to optimising drug therapy in some patients; this may be supplemented through the use of compliance aids. What is increasingly apparent, however, is that the role of the patient (irrespective of age) is critical in decision-making about medication, together with communication between patients and healthcare professionals. This has been articulated through the concept of concordance which has been described as a therapeutic alliance between the patient and healthcare professional. In addition, interventions employed to improve adherence must be multifaceted, and together with practical approaches (reducing unnecessary drugs and simplifying dosage regimens), the patient perspective must be considered. Good adherence should be seen as a means of achieving a satisfactory therapeutic result and not as an end in itself.

Journal ArticleDOI
TL;DR: It has been shown that the protons are emitted, in a quasilaminar fashion, from a region of transverse size of the order of 100-200 microm, which is equivalent to those of a much smaller source located several hundred microm in front of the foil.
Abstract: A study of the properties of multi-MeV proton emission from thin foils following ultraintense laser irradiation has been carried out. It has been shown that the protons are emitted, in a quasilaminar fashion, from a region of transverse size of the order of 100-200 microm. The imaging properties of the proton source are equivalent to those of a much smaller source located several hundred microm in front of the foil. This finding has been obtained by analyzing proton radiographs of periodically structured test objects, and is corroborated by observations of proton emission from laser-heated thick targets.

Journal ArticleDOI
TL;DR: It is demonstrated, for the first time, that the reaction of toluene and nitric acid in three different ionic liquids gives rise to three completely different products in high yield.

Journal ArticleDOI
19 Feb 2004-Nature
TL;DR: Reduced rates of discarding, particularly when coupled with reduced availability of small shoaling pelagic fish such as sandeel, result in an increase in predation by great skuas on other birds.
Abstract: It is clear that discards from commercial fisheries are a key food resource for many seabird species around the world(1-8). But predicting the response of seabird communities to changes in discard rates is problematic and requires historical data to elucidate the confounding effects of other, more 'natural' ecological processes. In the North Sea, declining stocks, changes in technical measures, changes in population structure(9) and the establishment of a recovery programme for cod (Gadus morhua(10)) will alter the amount of fish discarded. This region also supports internationally important populations of seabirds(11), some of which feed extensively, but facultatively, on discards, in particular on undersized haddock (Melanogrammus aeglefinus) and whiting (Merlangius merlangus)(1-3). Here we use long-term data sets from the northern North Sea to show that there is a direct link between discard availability and discard use by a generalist predator and scavenger-the great skua (Stercorarius skua). Reduced rates of discarding, particularly when coupled with reduced availability of small shoaling pelagic fish such as sandeel (Ammodytes marinus), result in an increase in predation by great skuas on other birds. This switching of prey by a facultative scavenger presents a potentially serious threat to some seabird communities.