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Selected AbstractsIs There a Case in Favour of Predictive Genetic Testing in Young Children?BIOETHICS, Issue 1 2001Stephen Robertson Genetic testing technology has brought the ability to predict the onset of diseases many years before symptoms appear and the use of such predictive testing is now widespread. The medical fraternity has met the application of this practice to children with caution. The justification for their predominantly prohibitive stance has revolved around the lack of a readily identifiable medical benefit in the face of potential psychological harms to the child. We argue that predictive testing can have important psychosocial benefits and that the interests of the child have been construed too narrowly. Proponents of a prohibitive stance also argue that testing in childhood breaches the child's future right to make the same decision as an autonomous adult and to maintain this information as confidential. We argue that predictive genetic testing of children is not necessarily a violation of the child's future autonomy. Indeed, in some cases, such testing may facilitate the development of autonomy in the maturing child. We argue that parents are generally best placed to judge what is in their own child's overall interests, and that a parental request for testing after appropriate genetic counselling should be respected unless there is clear evidence that the child will be harmed in an overall sense as a result of testing. [source] A comparative study of Java and C performance in two large-scale parallel applicationsCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 15 2009Aamir Shafi Abstract In the 1990s the Message Passing Interface Forum defined MPI bindings for Fortran, C, and C++. With the success of MPI these relatively conservative languages have continued to dominate in the parallel computing community. There are compelling arguments in favour of more modern languages like Java. These include portability, better runtime error checking, modularity, and multi-threading. But these arguments have not converted many HPC programmers, perhaps due to the scarcity of full-scale scientific Java codes, and the lack of evidence for performance competitive with C or Fortran. This paper tries to redress this situation by porting two scientific applications to Java. Both of these applications are parallelized using our thread-safe Java messaging system,MPJ Express. The first application is the Gadget-2 code, which is a massively parallel structure formation code for cosmological simulations. The second application uses the finite-domain time-difference method for simulations in the area of computational electromagnetics. We evaluate and compare the performance of the Java and C versions of these two scientific applications, and demonstrate that the Java codes can achieve performance comparable with legacy applications written in conventional HPC languages. Copyright © 2009 John Wiley & Sons, Ltd. [source] Ischaemic preconditioning is related to decreasing levels of extracellular adenosine that may be metabolically useful in the at-risk myocardium: an experimental study in the pigACTA PHYSIOLOGICA, Issue 1 2010A. Waldenström Abstract Aim:, ,Pre-treatment' with short repetitive periods of ischaemia (ischaemic preconditioning) has proved to be a powerful mechanism for modification of the extent of myocardial damage following acute coronary artery occlusion. The exact mechanism of protection induced by ischaemic preconditioning is not known. We herewith put forward a contributing component for protection with preconditioning involving a shift in the adenylate kinase (AK) equilibrium reaction in favour of adenosine triphosphate (ATP) formation. Methods:, A coronary artery was occluded in anaesthetized thoracotomized pigs to induce ischaemic preconditioning as well as a longer period of ischaemia. Microdialysis probes were inserted in ischaemic and control myocardium and were infused with 14C- adenosine with two different specific activities. 14C-lactate was identified and measured in the effluent. Results:,14C-adenosine was taken up by non-preconditioned and preconditioned myocardium during ischaemia. Significantly increased levels of 14C-lactate were recovered in preconditioned myocardium. 14C-adenosine with high specific activity resulted in a specific activity of lactate that was 2.7 times higher than that of lactate after administration of 14C-adenosine with low specific activity. Mass spectrography verified the identity of 14C-lactate. Conclusions:, Preconditioning up-regulates a new metabolic pathway (starting with 5,-nucleotidase and ending up with lactate) resulting in ATP formation in the micromolar range on top of another effect terminating in a useful shift in the AK equilibrium reaction in favour of ATP generation in the millimolar range. Although the up-regulation of the purine nucleoside phosphorylase pathway is clearly demonstrated, its biological relevance remains to be proved. [source] Cross-reactivity between nickel and palladium demonstrated by systemic administration of nickelCONTACT DERMATITIS, Issue 1 2005M. Hindsén Concomitant patch test reactions to nickel and palladium have frequently been reported in patients undergoing investigation because of suspected allergic contact dermatitis. Theoretically, these reactions can be explained by multiple, concomitant, simultaneous sensitization as well as cross-sensitization. We studied whether concomitant reactions to nickel and palladium could represent cross-sensitization in females hypersensitive to combinations of nickel, palladium and cobalt. Females were patch tested with serial dilutions of nickel sulfate, cobalt chloride and palladium chloride on the upper back. 1 month later, when the patch test reactions were gone, the patients were randomized into 2 groups that were challenged orally with either nickel or placebo. 1 day later, the areas of previous positive patch test reactions were read in a blind way looking for flare-up reactions. Nickel provocation but not placebo yielded flare-up reactions on sites previously tested with nickel (P = 0.012) and palladium (P = 0.006), but were also observed on sites previously tested with cobalt, even though this was not statistically significant. Flare-up reactions of previous patch test reactions to nickel and palladium after oral challenge with nickel speak in favour of a cross-reactivity mechanism. [source] Carbon dioxide emission trading, or not?CORPORATE SOCIAL RESPONSIBILITY AND ENVIRONMENTAL MANAGEMENT, Issue 4 2004An institutional analysis of company behaviour in Sweden The Kyoto Protocol opens up for market based solutions in climate change mitigation. A number of companies in Europe, North America and Asia have already practiced carbon dioxide emission trading. Sweden and Swedish companies have a tradition of being proactive in environmental policy and management. However, Swedish companies are acting reactively or even passively when it comes to emission trading. This paper aims to elucidate and explain the Swedish companies' behaviour on this matter. From our study, which focuses primarily on the energy and forestry sectors, it was found that companies are principally in favour of emission trading, but they have not developed initiatives for emission trading in practice. The study indicates that the institutional arrangements in which companies are situated do not encourage emission trading. Ambiguous government policies are claimed to prevent the companies from making long-term strategies on climate change mitigation in general and emission trading in particular. Copyright © 2004 John Wiley & Sons, Ltd and ERP Environment. [source] The role of caveolin-1 in cardiovascular regulationACTA PHYSIOLOGICA, Issue 2 2009A. Rahman Abstract Caveolae are omega-shaped membrane invaginations present in essentially all cell types in the cardiovascular system, and numerous functions have been ascribed to these structures. Caveolae formation depends on caveolins, cholesterol and polymerase I and transcript release factor-Cavin (PTRF-Cavin). The current review summarizes and critically discusses the cardiovascular phenotypes reported in caveolin-1-deficient mice. Major changes in the structure and function of heart, lung and blood vessels have been documented, suggesting that caveolae play a critical role at the interface between blood and surrounding tissue. According to an emerging paradigm, many of these changes are secondary to uncoupling of endothelial nitric oxide synthase. Thus, nitric oxide synthase not only synthesizes more nitric oxide in the absence of caveolin-1, but also more superoxide with potential pathogenic consequences. It is further argued that the vasodilating drive from increased nitric oxide production in caveolin-1-deficient mice is balanced by changes in the vascular media that favour increased dynamic resistance regulation. Harnessing the therapeutic opportunities buried in caveolae, while challenging, could expand the arsenal of treatment options in cancer, lung disease and atherosclerosis. [source] Trials update in walesCYTOPATHOLOGY, Issue 2007A. Fiander Three ongoing studies will be presented and discussed. Prevalence of Human Papillomavirus Infection in a South Wales Screening population Methods: A total of 10 000 consecutive, anonymous liquid based cytology screening samples were collected over a five month period in 2004. Age, cytology result and social deprivation score was provided for each specimen. The methodology was chosen to ensure inclusion of all women attending routine cervical screening, avoiding potential constraints associated with obtaining individual informed consent. The liquid based cytology samples were processed and reported by the receiving cytology laboratory and the residual specimens sent to the HPV Research Laboratory, Wales College of Medicine, where they were processed and stored at -80°C until analysis. High risk and low risk HPV Typing was undertaken using PCR , EIA (Jacobs et al 1997). Full high risk typing was performed on HPV positive specimens. Results: The study population had a mean age of 38 years with 92% negative, 5% borderline and 3% dyskaryotic cytology. The average social deprivation score was 17.4 (based upon the Welsh Index of multiple deprivation). The following results will be presented: HPV prevalence by age. HPV prevalence by cytology result. Type specific HPV prevalence in single and multiple infection. Conclusion: This study represents the largest type specific HPV Prevalence Study in the UK to date. As such it will form a useful base line against which to access performance of marketed HPV tests and evaluating the impact following implementation of HPV vaccination. [Funded by Welsh Office for Research and Development] CRISP , 1 Study (Cervical Randomized Intervention Study Protocol -1) Background: Indole-3-carbinol (I3C) and Diindolylmethane (DIM) are found in cruciferous vegetables and have been identified as compounds that could potentially prevent or halt carcinogenesis. I3C spontaneously forms DIM in vivo during acid digestion. I3C has been shown to prevent the development of cervical cancer in HPV 16 transgenic mice and both I3C and DIM have been shown to promote cell death in cervical cancer cell models. DIM is the major active bi-product of I3C and preliminary data indicate that DIM is active in cervical dysplasia and may be better tolerated than I3C. Aim: To investigate chemoprevention of high grade cervical neoplasia using Diindolylmethane (DIM) supplementation in women with low grade cytological abnormalities on cervical cytology. Objectives: To observe any reduction in the prevalence of histological proven high-grade cervical intraepithelial neoplasia (CIN) after 6 months of supplementation. ,,To observe any reduction in the prevalence of cytological abnormalities. ,,To observe any changes in the clinical appearance of the cervix. To assess acceptability and monitor any side effects of DIM supplementation. ,,To assess whether any benefit is seen in relation to Human Papillomavirus (HPV) status including HPV Type, Viral load and integration. Methods: This is a double blind randomized placebo-controlled trial involving 600,700 women with low grade cytological abnormalities on a cervical smear. Randomization is in the ratio of 2 : 1 in favour of active medication. Women with first mildly dyskaryotic smear or second borderline smear are eligible. They are asked to take two capsules daily for 6 months. At the end of 6 months they undergo repeat cervical cytology, HPV testing and colposcopy. Results: A progress report will be given for this ongoing study. [Funded: - Cancer Research UK] Type Specific HPV Infection in Welsh Cervical Cancers Background: Whilst there have been numerous studies of HPV infection associated with cervical cancer and on prevalence of Human Papillomavirus in diverse populations there have been no studies of these variables in the same population. Against a background of prophylactic HPV vaccination it is important to assess potential protection against cervical cancer within a given population. The most comprehensive analysis of HPV type specific cervical cancer is a meta-analysis published by the IARC in 2003. This however included only three UK based studies, totalling 118 cases, 75 of which were only investigated by HPV type PCR for four high risk types. None of this data was presented with associated population based prevalence data. Therefore, the research objectives for this study in combination with the first study above, are as follows: To determine the frequency of specific HPV types in cervical cancers in Wales. To compare the distribution of specific HPV types amongst cervical cancers with their prevalence in the general population. This will allow accurate delineation of the relationship between prevalence of specific HPV types in the general population and their association with clinically relevant disease. This information is a pre-requisite to assess the potential impact of prophylactic vaccination against HPV infection in Wales. Methods: Welsh Cervical Cancer specimens from 2000,2005 will be identified from pathology departments within Wales. The pathology of each tumour will be reviewed by a single Gynaecological Pathologist. The age of the patient and pathological features of the tumour will be noted. DNA will be extracted from the paraffin sections and HPV typed by PCR-EIA. Results: A progress report will be given for this ongoing study. [Funded by Welsh Office for Research and Development] [source] Peripheral endothelial cells are not reliable in differentiating primary benign and malignant hepatocellular lesions in fine needle aspirates of the liverCYTOPATHOLOGY, Issue 3 2002GORDON H. YU The distinction of hepatocellular carcinoma (HCC) from benign lesions of the liver in fine needle aspiration (FNA) specimens can be problematic. In an attempt to separate well-differentiated HCC from benign hepatocellular lesions, the presence of tissue fragments displaying peripheral endothelial cells (PE) has been proposed in a previous study as a useful feature in favour of malignancy. In this study, we evaluated slides from 59 cases of liver masses undergoing FNA (19 HCC, 40 benign) and evaluated them for the presence of tissue fragments containing PE. We found that 90% of cases of HCC contained tissue fragments in which PE were either focally present or abundant. However, 68% of cases containing only benign hepatocytes also contained tissue fragments in which PE were at least focally present. In addition, it appears that within the group of benign lesions, the presence of PE was related to the overall cellularity of the specimen rather than the specific nature of the lesion. Thus, the presence of PE in tissue fragments does not, in isolation, appear to be a useful morphological feature for the separation of benign and malignant hepatocellular lesions in FNA material. [source] Rushing for Gold: Mobility and Small-Scale Mining in East AfricaDEVELOPMENT AND CHANGE, Issue 2 2009Jesper Bosse Jønsson ABSTRACT African rural dwellers have faced depressed economic prospects for several decades. Now, in a number of mineral-rich countries, multiple discoveries of gold and precious stones have attracted large numbers of prospective small-scale miners. While their ,rush' to, and activities within, mining sites are increasingly being noted, there is little analysis of miners' mobility patterns and material outcomes. In this article, on the basis of a sample survey and interviews at two gold-mining sites in Tanzania, we probe when and why miners leave one site in favour of another. Our findings indicate that movement is often ,rushed' but rarely rash. Whereas movement to the first site may be an adventure, movement to subsequent sites is calculated with knowledge of the many risks entailed. Miners spend considerable time at each site before migrating onwards. Those with the highest site mobility tend to be more affluent than the others, suggesting that movement can be rewarding for those willing to ,try their luck' with the hard work and social networking demands of mining another site. [source] The Distribution of Subsidized Agricultural Credit in Brazil: Do Interest Groups Matter?DEVELOPMENT AND CHANGE, Issue 3 2001Steven M. Helfand This article examines the unequal distribution of credit and credit subsidies in the Brazilian agricultural sector from 1969 to 1990. Total credit subsidies exceeded US$ 40 billion in this period. The distribution across crops is studied econometrically. After controlling for area, the crops that benefited most had superior access to credit institutions, were tradeable, had high prices, and were not perennials. Proxies for collective action by crop were an unimportant determinant of credit policy, while a bias in favour of large producers was evident. Alternative explanations for this bias are discussed, including collective action by farm size and transaction costs in lending. [source] World Income Distribution and Tax Reform: What Tax Systems Do Low-Income Countries Need?DEVELOPMENT POLICY REVIEW, Issue 3 2003J. Ram Pillarisetti This article develops a new method for assessing relative direct tax burdens across all countries, treating the world as a single economic entity and assuming identical preferences across countries. Empirical results show that the new direct tax burden indices are significantly high in low-income countries in comparison with middle- and high-income countries. This article argues in favour of narrowing the base of income and capital gains tax in low-income countries and a long-term convergence of the tax burden levels across countries. Future research into tax reforms in low-income countries should focus simultaneously on economic growth, quality of life and the natural environment. [source] Schizophrenia treatment: content versus deliveryACTA PSYCHIATRICA SCANDINAVICA, Issue 2009J. Van Os Objective:, To review the evidence supporting the importance of ensuring that patients with psychiatric disorders receive an optimal and appropriate level of non-pharmacological treatment, and how Assertive Community Treatment (ACT) may be able to contribute to this aim. Method:, Analysis of data from selected individual published studies on ACT, in addition to reviews from the Cochrane Library, and other study groups. Results:, Treatment management using ACT appears to offer benefits in terms of reduction in hospitalisation, although there is some debate as to whether this is the most representative outcome measure. Preliminary indications using remission as an outcome measure have also shown promising results in favour of ACT. Conclusion:, While further investigation and validation are necessary, current data indicate that ACT may be an appropriate strategy to facilitate the delivery of treatment to patients with psychotic disorders. [source] Assessment of cerebral visual impairment with the L94 visual perceptual battery: clinical value and correlation with MRI findingsDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 3 2009E ORTIBUS MD In this article we describe visual perceptual abilities of a clinical population, referred for visual problems to our multidisciplinary team and assessed with the five computer tasks from the L94 visual perceptual battery. Clinical and neuroimaging findings were correlated with the findings on this task battery. Seventy children (35 males, 35 females) constituted our cohort. Age ranged from 4 to 20 years (mean 7y [SD 3y]). Forty children were born before 37 weeks gestational age. Thirty-six children had cerebral palsy (CP), of whom 24 had spastic diplegia, five had spastic hemiplegia, and four had spastic quadriplegia. Three children had ataxic CP. Perceptual visual impairment (PVI) was established in comparison to the performance age obtained on non-verbal intelligence subtests, instead of chronological age. Our results suggest that children with a history of preterm birth and a clinical CP picture are most at risk for a specific PVI. Correlations among other clinical variables did not define a clinical subgroup more at risk. Children with periventricular leucomalacia were almost equally represented in both PVI and non-PVI groups. Normal magnetic resonance imaging did not exclude the presence of PVI. In these children, however, we found another impairment profile, more in favour of dorsal stream impairment. [source] Treatment of symptomatic diabetic polyneuropathy with the antioxidant ,-lipoic acid: a meta-analysisDIABETIC MEDICINE, Issue 2 2004D. Ziegler Abstract Aims To determine the efficacy and safety of 600 mg of ,-lipoic acid given intravenously over 3 weeks in diabetic patients with symptomatic polyneuropathy. Methods We searched the database of VIATRIS GmbH, Frankfurt, Germany, for clinical trials of ,-lipoic acid according to the following prerequisites: randomized, double-masked, placebo-controlled, parallel-group trial using ,-lipoic acid infusions of 600 mg i.v. per day for 3 weeks, except for weekends, in diabetic patients with positive sensory symptoms of polyneuropathy which were scored by the Total Symptom Score (TSS) in the feet on a daily basis. Four trials (ALADIN I, ALADIN III, SYDNEY, NATHAN II) comprised n = 1258 patients (,-lipoic acid n = 716; placebo n = 542) met these eligibility criteria and were included in a meta-analysis based on the intention-to-treat principle. Primary analysis involved a comparison of the differences in TSS from baseline to the end of i.v. Treatment between the groups treated with ,-lipoic acid or placebo. Secondary analyses included daily changes in TSS, responder rates (, 50% improvement in TSS), individual TSS components, Neuropathy Impairment Score (NIS), NIS of the lower limbs (NIS-LL), individual NIS-LL components, and the rates of adverse events. Results After 3 weeks the relative difference in favour of ,-lipoic acid vs. placebo was 24.1% (13.5, 33.4) (geometric mean with 95% confidence interval) for TSS and 16.0% (5.7, 25.2) for NIS-LL. The responder rates were 52.7% in patients treated with ,-lipoic acid and 36.9% in those on placebo (P < 0.05). On a daily basis there was a continuous increase in the magnitude of TSS improvement in favour of ,-lipoic acid vs. placebo which was noted first after 8 days of treatment. Among the individual components of the TSS, pain, burning, and numbness decreased in favour of ,-lipoic acid compared with placebo, while among the NIS-LL components pin-prick and touch-pressure sensation as well as ankle reflexes were improved in favour of ,-lipoic acid after 3 weeks. The rates of adverse events did not differ between the groups. Conclusions The results of this meta-analysis provide evidence that treatment with ,-lipoic acid (600 mg/day i.v.) over 3 weeks is safe and significantly improves both positive neuropathic symptoms and neuropathic deficits to a clinically meaningful degree in diabetic patients with symptomatic polyneuropathy. Diabet. Med. 21, 114,121 (2004) [source] Comparison between repaglinide and glipizide in Type 2 diabetes mellitus: a 1-year multicentre studyDIABETIC MEDICINE, Issue 5 2001S. Madsbad Abstract Aims To evaluate the long-term effectiveness and safety of repaglinide, a novel prandial glucose regulator, in comparison with glipizide in the treatment of patients with Type 2 diabetes. Methods Diet or tablet-treated patients with Type 2 diabetes (n = 256; age 40,75 years, body mass index (BMI) 20,35 kg/m2, HbA1c 4.2,12.8%), without signs of severe microvascular or macrovascular complications, were included in this double-blind, multicentre, parallel-group comparative trial. Patients were randomized at a 2:1 ratio to repaglinide, 1,4 mg at mealtimes, or glipizide, 5,15 mg daily. Results Changes in fasting blood glucose (FBG) and HbA1c during the 12 months of treatment showed a significant difference in favour of repaglinide. In oral hypoglycaemic agents (OHA)-naive patients, HbA1c decreased in the repaglinide and glipizide groups by 1.5% and 0.3%, respectively (P < 0.05 between groups). Fasting blood glucose decreased in the repaglinide group by 2.4 mmol/l and increased in the glipizide group by 1.0 mmol/l (P < 0.05 between groups). In the study population as a whole, repaglinide was able to maintain glycaemic control (HbA1c level) during the 1-year study period, whereas control deteriorated significantly with glipizide. Change in HbA1c from baseline was significantly better with repaglinide than with glipizide after 12 months (P < 0.05). In addition, FBG deteriorated significantly in the glipizide group compared with the repaglinide group (P < 0.05). No patients in either group experienced a major hypoglycaemic event; the number of patients experiencing minor hypoglycaemia was similar in the repaglinide and glipizide groups (15% and 19%, respectively). Conclusions Repaglinide, given as a prandial glucose regulator, is shown to be an effective and safe treatment of patients with Type 2 diabetes, and is better than glipizide in controlling HbA1c and FBG levels, overall, and in OHA-naive patients. Diabet. Med. 18, 395,401 (2001) [source] Ontological Priority, Fundamentality and MonismDIALECTICA, Issue 3 2009Winner of the 2008 dialectica essay prize In recent work, the interrelated questions of whether there is a fundamental level to reality, whether ontological dependence must have an ultimate ground, and whether the monist thesis should be endorsed that the whole universe is ontologically prior to its parts have been explored with renewed interest. Jonathan Schaffer has provided arguments in favour of ,priority monism' in a series of articles (2003, 2004, 2007a, 2007b, forthcoming). In this paper, these arguments are analysed, and it is claimed that they are not compelling: in particular, the possibility that there is no ultimate level of basic entities that compose everything else is on a par with the possibility of infinite ,upward' complexity. The idea that we must, at any rate, postulate an ontologically fundamental level for methodological reasons (Cameron 2008) is also discussed and found unconvincing: all things considered, there may be good reasons for endorsing ,metaphysical infinitism'. In any event, a higher degree of caution in formulating metaphysical claims than found in the extant literature appears advisable. [source] Particulars, Modes and Universals: An examination of E.J. Lowe's Four-Fold OntologyDIALECTICA, Issue 3 2004Fraser MacBride Is there a particular-universal distinction? Ramsey famously advocated scepticism about this distinction. In "Some Formal Ontological Relations" E.J. Lowe argues against Ramsey that a particular-universal distinction can be made out after all if only we allow ourselves the resources to distinguish between the elements of a four-fold ontology. But in defence of Ramsey I argue that the case remains to be made in favour of either (1) the four-fold ontology Lowe recommends or (2) the articulation of a particular-universal distinction within it. I also argue that the case remains to be made against (3) a spatio-temporal conception of the particular-universal distinction. [source] On the justification for civil commitmentACTA PSYCHIATRICA SCANDINAVICA, Issue 399 2000G. Høyer This paper explores some of the controversies in the debate regarding the justification of civil commitment. The sometimes conflicting values reflected in the mental health legislation, human rights principles, moral philosophy and psychiatric professional standards are discussed. In spite of the often substantial use of civil commitment in many countries, there are almost no scientifically sound studies addressing the outcome of coercive treatment. The paper establishes that the traditional arguments in favour of civil commitment, like lack of insight and competence as well as the effectiveness of civil commitment, are poorly founded. The paper concludes that there seems to be a general agreement that civil commitment of patients who are dangerous to themselves or others should be the responsibility of the mental health care system, while civil commitment for treatment purposes is more controversial and hard to justify. [source] Conifers as invasive aliens: a global survey and predictive frameworkDIVERSITY AND DISTRIBUTIONS, Issue 5-6 2004David M. Richardson ABSTRACT We summarize information on naturalized and invasive conifers (class Pinopsida) worldwide (data from 40 countries, some with remote states/territories), and contrast these findings with patterns for other gymnosperms (classes Cycadopsida, Gnetopsida and Ginkgoopsida) and for woody angiosperms. Eighty conifer taxa (79 species and one hybrid; 13% of species) are known to be naturalized, and 36 species (6%) are ,invasive'. This categorization is based on objective and conservative criteria relating to consistency of reproduction, distance of spread from founders, and degree of reliance on propagules from the founder population for persistence in areas well outside the natural range of species. Twenty-eight of the known invasive conifers belong to one family (Pinaceae) and 21 of these are in one genus (Pinus). The Cupressaceae (including Taxodiaceae) has six known invasive species (4%) in four genera, but the other four conifer families have none. There are also no known invasive species in classes Cycadopsida, Gnetopsida or Ginkgoopsida. No angiosperm family comprising predominantly trees and shrubs has proportionally as many invasive species as the Pinaceae. Besides the marked taxonomic bias in favour of Pinaceae, and Pinus in particular, invasiveness in conifers is associated with a syndrome of life-history traits: small seed mass (< 50 mg), short juvenile period (< 10 year), and short intervals between large seed crops. Cryptomeria japonica, Larix decidua, Picea sitchensis, Pinus contorta, Pinus strobus, and Pseudotsuga menziesii exemplify this syndrome. Many rare and endangered conifer species exhibit opposite characters. These results are consistent with earlier predictions made using a discriminant function derived from attributes of invasive and noninvasive Pinus species. Informative exceptions are species with small seeds (< 4 mg, e.g. Chamaecyparis spp., Pinus banksiana, Tsuga spp. , mostly limited to wet/mineral substrates) or otherwise ,non-invasive' characters (e.g. large seeds, fleshy fruits, e.g. Araucaria araucana, Pinus pinea, Taxus baccata that are dependent on vertebrates for seed dispersal). Most conifers do not require coevolved mutualists for pollination and seed dispersal. Also, many species can persist in small populations but have the genetic and reproductive capacity to colonize and increase population size rapidly. The underlying mechanisms mediating conifer invasions are thus easier to discern than is the case for most angiosperms. Further information is needed to determine the extent to which propagule pressure (widespread dissemination, abundant plantings, long history of cultivation) can compensate for low ,inherent invasiveness'. [source] The origin of higher taxa: macroevolutionary processes, and the case of the mammalsACTA ZOOLOGICA, Issue 1 2007T. S. Kemp Abstract The origin of a new higher taxon is characterized by a long-term phylogenetic trend, involving evolutionary changes in a large number of characters. At this phylogenetic level, the conflict between internal integration of the phenotype and its evolvability can be resolved by the correlated progression model, in which many disparate traits evolve by a sequence of small increments in loose correlation with one another, rather than by the modularity model. The trend leading to the new higher taxon implies the existence of a long ridge in an adaptive landscape. An evolutionary lineage tracking it requires adaptive changes in broad biological characteristics, involving many traits. Species selection is a possible additional driver of the trend. These conclusions are tested against the synapsid fossil record of the origin of mammals. The reconstructed sequence of acquisition of mammalian traits supports the correlated progression model. The adaptive ridge involved is postulated to have been a sequence of overlapping niches requiring increasing ability to remain active in daily and seasonally fluctuating environments by means of increasing internal regulation. An inferred speciation bias in favour of relatively small, relatively more progressive carnivores indicates that species selection was also involved in driving the trend. Palaeoenvironmental evidence indicates that ecological opportunity probably played a role at certain points along the lineage. [source] An evaluation of a visual biofeedback intervention in dyslexic adultsDYSLEXIA, Issue 1 2005Elizabeth Liddle Abstract A prototype of a biofeedback system designed to treat dyslexia by improving heart-rate variability was evaluated in a single blind study of dyslexic adults. Treatment consisted of four 15 minute exposures to a visual display synchronized with either the participant's own cardiac cycle (intervention condition), or of a synthesized cardiac cycle (placebo condition). Repeated measures were made of picture naming speed, single word reading speed and accuracy, copying speed, heart-rate variability and performance on a lateralized visual temporal order judgement task. Small but significant improvements were found in reading and naming speed in the treatment group relative to the placebo group. No significant improvements were found in unspeeded reading measures. Results from heart-rate measures indicated that treatment had effected a shift in the ratio between parameters reflecting the influence of the sympathetic and parasympathetic autonomic nervous systems (ANS), respectively, in favour of the parasympathetic. In the temporal order judgement task, participants who received treatment showed a reduced level of overall improvement relative to that seen in those who received placebo, coupled with evidence of a shift in visual attention from left to right hemifield in their pattern of performance. The results are interpreted as indicating that the treatment induces a shift in autonomic balance in favour of the parasympathetic ANS, and that this shift is also reflected in increased efficiency of left cerebral hemisphere circuits implicated in the perceptual-motor processes required for naming and reading fluency. Conversely, it is also reflected in lower spatial awareness of peripheral visual stimuli, particularly those presented to left hemifield. Copyright © 2004 John Wiley & Sons, Ltd. [source] Estimating the mean speed of laminar overland flow using dye injection-uncertainty on rough surfacesEARTH SURFACE PROCESSES AND LANDFORMS, Issue 4 2001David Dunkerley Abstract A common method for estimating mean flow speeds in studies of surface runoff is to time the travel of a dye cloud across a measured flow path. Motion of the dye front reflects the surface flow speed, and a correction must be employed to derive a value for the profile mean speed, which is always lower. Whilst laminar flow conditions are widespread in the interrill zone, few data are available with which to establish the relationship linking surface and profile mean speeds, and there are virtually none for the flow range 100,<,Re,<,500 (Re,=,Reynolds number) which is studied here. In laboratory experiments on a glued sand board, mean flow speeds were estimated from both dye speeds and the volumetric flow relation v,=,Q/wd with d measured using a computer-controlled needle gauge at 64 points. In order to simulate conditions applicable to many dryland soils, the board was also roughened with plant litter and with ceramic tiles (to simulate surface stone cover). Results demonstrate that in the range 100,<,Re,<,500, there is no consistent relation between surface flow speeds and the profile mean. The mean relationship is v,=,0·56 vsurf, which departs significantly from the theoretical smooth-surface relation v,=,0·67 vsurf, and exhibits a considerable scatter of values that show a dependence on flow depth. Given the inapplicability of any fixed conversion factor, and the dependence on flow depth, it is suggested that the use of dye timing as a method for estimating v be abandoned in favour of precision depth measurement and the use of the relation v,=,Q/wd, at least within the laminar flow range tested. Copyright © 2001 John Wiley & Sons, Ltd. [source] Phorid fly parasitoids of invasive fire ants indirectly improve the competitive ability of a native antECOLOGICAL ENTOMOLOGY, Issue 5 2004Natasha J. Mehdiabadi Abstract., 1.,The red imported fire ant, Solenopsis invicta Buren (Hymenoptera: Formicidae), is an invasive species of south-eastern U.S.A. Since its introduction from South America approximately 70 years ago, this pest has devastated natural biodiversity. 2.,Due to such ecological costs, Pseudacteon phorid fly parasitoids (Diptera: Phoridae) from South America are being introduced into the U.S.A. as a potential biological control agent. Here, the indirect effects of these specialised parasitoids on an interspecific native ant competitor, Forelius mccooki (Hymenoptera: Formicidae), are evaluated. 3.,Over the course of a 50-day laboratory experiment, the results show that the native ant improved aspects of exploitative, but not interference, competition when S. invicta -attacking flies were present compared with when they were absent. 4.,Forelius mccooki colonies from the phorid treatment had approximately twice as many foragers at food baits relative to controls; however, there was no significant difference in interference aspects of competition or native ant colony growth between the two treatments. 5.,These results suggest that the S. invicta -specialised parasitoids help shift the competitive balance more in favour of F. mccooki than if these flies were not present; however, this competitive advantage does not translate into increased colony growth after 50 days. These laboratory findings are interpreted with regard to the more complex interactions in the field. [source] TAXING LAND VALUE IS JUST ANOTHER QUESTIONABLE TAXECONOMIC AFFAIRS, Issue 4 2006Oliver Marc Hartwich There has recently been much public debate about the introduction of a land value tax. To its supporters such a tax promises to achieve several goals simultaneously. On closer inspection, however, the arguments in favour of land value taxation are not convincing. On the contrary, the economic foundations on which proponents of this tax rely are dubious, and there are significant legal, moral and practical problems with land value taxation. [source] Lancashire, India, and shifting competitive advantage in cotton textiles, 1700,1850: the neglected role of factor prices1ECONOMIC HISTORY REVIEW, Issue 2 2009STEPHEN BROADBERRY In the early eighteenth century, wages in Britain were more than four times as high as in India, the world's major exporter of cotton textiles. This induced the adoption of more capital-intensive production methods in Britain and a faster rate of technological progress, so that competitive advantage had begun to shift in Britain's favour by the late eighteenth century. However, the completion of the process was delayed until after the Napoleonic Wars by increasing raw cotton costs, before supply adjusted to the major increase in demand for inputs. [source] The alcohol industry and public interest scienceADDICTION, Issue 2 2010Kerstin Stenius ABSTRACT Aims This report argues that the growing involvement of the alcohol industry in scientific research needs to be acknowledged and addressed. It suggests a set of principles to guide ethical decision-making in the future. Methods We review relevant issues with regard to relationships between the alcohol industry and the international academic community, especially alcohol research scientists. The guiding principles proposed are modelled after expert committee statements, and describe the responsibilities of governmental agencies, the alcohol industry, journal editors and the academic community. These are followed by recommendations designed to inform individuals and institutions about current ,best practices' that are consistent with the principles. Findings and conclusions Growing evidence from the tobacco, pharmaceutical and medical fields suggests that financial interests of researchers may compromise their professional judgement and lead to research results that are biased in favour of commercial interests. It is recommended that the integrity of alcohol science is best served if all financial relationships with the alcoholic beverage industry are avoided. In cases where research funding, consulting, writing assignments and other activities are initiated, institutions, individuals and the alcoholic beverage industry itself are urged to follow appropriate guidelines that will increase the transparency and ethicality of such relationships. [source] Trade Balance and Exchange Rate: Unit Roots, Co-integration and Long Memory in the US and the UKECONOMIC NOTES, Issue 1 2008Luis A. Gil-Alana This paper deals with the relationship between the balance of trade and the exchange rate in the US/UK case. Many authors have studied this issue for many countries, but despite the intensive research, there is still no agreement about the effectiveness of currency devaluation to increase a country's balance of trade. We first analyse the relationship between the two variables using unit roots and co-integration methods, and the results are ambiguous. We try a new approach based on fractional integration. The unit root hypothesis is rejected in case of the trade balance in favour of smaller orders of integration, while this hypothesis is not rejected for the exchange rate. Thus, the two series do not possess the same order of integration. We sort this problem out by taking the exchange rate as an exogenous variable, and including it in a regression model where the residuals might follow a fractionally integrated model. [source] Threshold Dynamics of Short-term Interest Rates: Empirical Evidence and Implications for the Term StructureECONOMIC NOTES, Issue 1 2008Theofanis Archontakis This paper studies a nonlinear one-factor term structure model in discrete time. The short-term interest rate follows a self-exciting threshold autoregressive (SETAR) process that allows for shifts in the intercept and the variance. In comparison with a linear model, we find empirical evidence in favour of the threshold model for Germany and the US. Based on the estimated short-rate dynamics we derive the implied arbitrage-free term structure of interest rates. Since analytical solutions are not feasible, bond prices are computed by means of Monte Carlo integration. The resulting term structure captures stylized facts of the data. In particular, it implies a nonlinear relation between long rates and the short rate. [source] Sterling and the EuroECONOMIC OUTLOOK, Issue 1 2000Erik Britton The question of whether and when sterling should join Economic and Monetary Union is likely to be one of the key battlegrounds in the next election campaign. In this article, Erik Britton and Scott Livermore argue that there is no clear economic case in favour of sterling's entry to EMU. However, if as the government asserts , the political will to join exists, steps could be taken now, adjusting the mix of macroeconomic policy, to ensure that convergence was likely shortly after the next election. [source] The Proposed Privatisation of Queensland MotorwaysECONOMIC PAPERS: A JOURNAL OF APPLIED ECONOMICS AND POLICY, Issue 1 2010Ross Guest L51; R42; R48 This article evaluates the proposed sale of the tolling rights on Queensland Motorways from an economic welfare perspective. Weighing against the sale are arguments about optimal risk allocation and network externalities. In contrast, there is a productive efficiency case in favour of the sale. Privatisation also raises questions about private monopoly power and the delivery of community service obligations, although these could be handled through contract specifications. The sale price is essentially a distributional issue. The back-of-the-envelope financial analysis here suggests that the mooted sale price of $3 billion would undervalue the asset and therefore transfer net worth from Queensland taxpayers to private investors. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||