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Selected AbstractsSmaller amphipod mothers show stronger trade-offs between offspring size and numberECOLOGY LETTERS, Issue 2 2000Douglas S. Glazier Trade-offs between embryo mass and number were studied in 10 populations of the freshwater amphipod Gammarus minus. Trade-offs were stronger in populations with small brooding females than in those with larger brooding females. Relationships between embryo mass and maternal body mass were also stronger in populations dominated by small versus large brooding females. These patterns are likely the result of morphological constraints, at least in part. Embryo size is more affected by brood size and maternal size in small mothers, probably because of offspring-packaging constraints associated with small brood pouches. Energy constraints appear to be less important. These results suggest that body size may not only affect the magnitude of individual life-history traits, as is well known, but also the covariance between traits. [source] Comment on: Tattooing of skin results in transportation and light-induced decomposition of tattoo pigmentsEXPERIMENTAL DERMATOLOGY, Issue 1 2010Gregor B. E. Jemec Abstract:, Decorative tattoos have become a common feature of many societies. Their popularity appears mainly driven by fashion, and scant attention has been paid to any associated risk. The risks can be associated either with the tattooees' proclivity for risk taking in general, or with the substances used in the tattoos. It is well established that tattoo pigments wander widely in the body after they have been injected, and research now suggests that azo pigments may become mutagenic after exposure to either natural light or laser light. This may not only affect the risk profile of tattoos themselves, but also tattoo removal using lasers. [source] Market Implications of the Audit Quality and Auditor Switches: Evidence from ChinaJOURNAL OF INTERNATIONAL FINANCIAL MANAGEMENT & ACCOUNTING, Issue 1 2009Z. Jun Lin Independent audits enhance the credibility of corporate financial reports and assist investors to make rational decisions in the capital market. Nonetheless, the utility of the auditing function depends upon the quality of audits, which is determined by the independence and expertise of auditors. Hence, auditor choice and switch will not only affect an audit's quality, but will also influence decisions made by investors and other market participants. The purpose of this paper is to investigate how investors respond to the quality of audits and auditor switches in the Chinese context. Empirical results show that the quality of an audit and switching to a larger auditor have a positive (negative) impact on earnings response coefficients (ERCs) for firms with positive (negative) abnormal earnings. In contrast, switching to a smaller auditor has a negative (positive) impact on ERCs for firms with positive (negative) abnormal earnings. These results suggest that large auditing firms (Top 10) in China are perceived as more effective for curbing income-increased earnings management, which leads to higher (lower) ERCs for clients with positive (negative) abnormal earnings. Firms' switching to a larger auditor may signal high-quality earnings. Therefore, investors more often increase stock prices when firms have positive abnormal earnings and less often depreciate prices for negative abnormal earnings. Similarly, switching to a smaller auditor may signal lower earning quality, resulting in opposite market responses. In general, the empirical evidence suggests that audit information is valued by the capital market in China. Large auditing firms have been able to product-differentiate themselves within the Chinese stock market. [source] Ginsenoside Re and Notoginsenoside R1: Immunologic Adjuvants with Low Haemolytic EffectCHEMISTRY & BIODIVERSITY, Issue 7 2006Hong-Xiang Sun Abstract The further purification of the total saponins from the roots of Panax notoginseng (Burk.) F.,H. Chen by ordinary and reversed-phase silica-gel, as well as Sephadex LH-20 chromatography afforded two adjuvant active dammarane-type saponins, ginsenoside Re (1) and notoginsenoside R1 (2). These two saponins were evaluated for haemolytic activities and adjuvant potentials on the cellular and humoral immune responses of ICR mice against ovalbumin (OVA). The concentrations inducing 50% of the maximum haemolysis (HD50), using 0.5% red blood cell suspensions, were 469.6±16.9 and 420.4±22.9 ,g/ml for 1 and 2, respectively. Compounds 1 and 2 significantly increased the concanavalin A (Con A)-, lipopolysaccharide (LPS)-, and OVA-induced splenocyte proliferation in the OVA-immunized mice (P<0.05, P<0.01, or P<0.001). The OVA-specific IgG, IgG1, and IgG2b antibody titres in serum were also significantly enhanced by 1 and 2 compared with OVA control group (P<0.05, P<0.01, or P<0.001). The results indicate that 1 and 2 showed a slight haemolytic activity and significant adjuvant effect on specific antibody and cellular immune response against OVA in mice, and that the type of the terminal sugar of the sugar chain at C(6) of protopanaxatriol could not only affect their haemolytic activities and adjuvant potentials, but have significant effects on the nature of the immune responses. The information about this structurefunction relationship might be useful for developing semisynthetic dammarane-type saponin derivatives with immunological adjuvant activity. [source] Genetics of Type 2 diabetesDIABETIC MEDICINE, Issue 5 2005I. Barroso Abstract Type 2 diabetes (T2D) has become a health-care problem worldwide, with the rise in disease prevalence being all the more worrying as it not only affects the developed world but also developing nations with fewer resources to cope with yet another major disease burden. Furthermore, the problem is no longer restricted to the ageing population, as young adults and children are also being diagnosed with T2D. In recent years, there has been a surge in the number of genetic studies of T2D in attempts to identify some of the underlying risk factors. In this review, I highlight the main genes known to cause uncommon monogenic forms of diabetes (e.g. maturity-onset diabetes of the young,MODY,and insulin resistance syndromes), as well as describe some of the main approaches used to identify genes involved in the more common forms of T2D that result from the interaction between environmental risk factors and predisposing genotypes. Linkage and candidate gene studies have been highly successful in the identification of genes that cause the monogenic variants of diabetes and, although progress in the more common forms of T2D has been slow, a number of genes have now been reproducibly associated with T2D risk in multiple studies. These are discussed, as well as the main implications that the diabetes gene discoveries will have in diabetes treatment and prevention. [source] Rapid evolution in introduced species, ,invasive traits' and recipient communities: challenges for predicting invasive potentialDIVERSITY AND DISTRIBUTIONS, Issue 4 2008Kenneth D. Whitney ABSTRACT The damaging effects of invasive organisms have triggered the development of Invasive Species Predictive Schemes (ISPS). These schemes evaluate biological and historical characteristics of species and prioritize those that should be the focus of exclusion, quarantine, and/or control. However, it is not clear how commonly these schemes take microevolutionary considerations into account. We review the recent literature and find that rapid evolutionary changes are common during invasions. These evolutionary changes include rapid adaptation of invaders to new environments, effects of hybridization, and evolution in recipient communities. Strikingly, we document 38 species in which the specific traits commonly associated with invasive potential (e.g. growth rate, dispersal ability, generation time) have themselves undergone evolutionary change following introduction, in some cases over very short (, 10 year) timescales. In contrast, our review of 29 ISPS spanning plant, animal, and microbial taxa shows that the majority (76%) envision invading species and recipient communities as static entities. Those that incorporate evolutionary considerations do so in a limited way. Evolutionary change not only affects the predictive power of these schemes, but also complicates their evaluation. We argue that including the evolutionary potential of species and communities in ISPS is overdue, present several metrics related to evolutionary potential that could be incorporated in ISPS, and provide suggestions for further research on these metrics and their performance. Finally, we argue that the fact of evolutionary change during invasions begs for added caution during risk assessment. [source] Expression of the aspartate/glutamate mitochondrial carriers aralar1 and citrin during development and in adult rat tissuesFEBS JOURNAL, Issue 13 2002Araceli Del Arco Aralar1 and citrin are members of the subfamily of calcium-binding mitochondrial carriers and correspond to two isoforms of the mitochondrial aspartate/glutamate carrier (AGC). These proteins are activated by Ca2+ acting on the external side of the inner mitochondrial membrane. Although it is known that aralar1 is expressed mainly in skeletal muscle, heart and brain, whereas citrin is present in liver, kidney and heart, the precise tissue distribution of the two proteins in embryonic and adult tissues is largely unknown. We investigated the pattern of expression of aralar1 and citrin in murine embryonic and adult tissues at the mRNA and protein levels. In situ hybridization analysis indicates that both isoforms are expressed strongly in the branchial arches, dermomyotome, limb and tail buds at early embryonic stages. However, citrin was more abundant in the ectodermal components of these structures whereas aralarl had a predominantly mesenchymal localization. The strong expression of citrin in the liver was acquired postnatally, whereas the characteristic expression of aralar1 in skeletal muscle was detected at E18 and that in the heart began early in development (E11) and was preferentially localized to auricular myocardium in late embryonic stages. Aralar1 was also expressed in bone marrow, T-lymphocytes and macrophages, including Kupffer cells in the liver, indicating that this is the major AGC isoform present in the hematopoietic system. Both aralar1 and citrin were expressed in fetal gut and adult stomach, ovary, testis, and pancreas, but only aralar1 is enriched in lung and insulin-secreting ,,cells. These results show that aralar1 is expressed in many more tissues than originally believed and is absent from hepatocytes, where citrin is the only AGC isoform present. This explains why citrin deficiency in humans (type II citrullinemia) only affects the liver and suggests that aralar1 may compensate for the lack of citrin in other tissues. [source] Total Factor Productivity and Monetary Policy: Evidence from Conditional Volatility,INTERNATIONAL FINANCE, Issue 2 2007Nicholas Apergis This paper empirically assesses whether monetary policy and its volatility affect real economic activity through their effect on the aggregate supply side of the macroeconomy. Analysts typically argue that monetary policy either does not affect the real economy (the classical dichotomy) or only affects the real economy in the short run through aggregate demand (new Keynesian or new classical theories). Real business cycle theorists try to explain the business cycle with supply-side productivity shocks. We provide some preliminary evidence about how monetary policy and its volatility affect the aggregate supply side of the macroeconomy through their effect on total factor productivity and its volatility. Total factor productivity provides an important measure of supply-side performance. The results show that monetary policy and its volatility exert a positive and statistically significant effect on the supply side of the macroeconomy. Moreover, the findings buttress the importance of reducing short-run swings in monetary policy variables as well as support the adoption of an optimal money supply rule. Our results also prove consistent with the effective role of monetary policy during the so-called ,Great Moderation' in US gross domestic product volatility beginning in the early 1980s. [source] A comprehensive techno-economic analysis method for power generation systems with CO2 captureINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 4 2010Gang Xu Abstract A new comprehensive techno-economic analysis method for power generation systems with CO2 capture is proposed in this paper. The correlative relationship between the efficiency penalty, investment increment, and CO2 avoidance cost is established. Through theoretical derivation, typical system analysis, and variation trends investigation, the mutual influence between technical and economic factors and their impacts on the CO2 avoidance cost are studied. At the same time, the important role that system integration plays in CO2 avoidance is investigated based on the analysis of a novel partial gasification CO2 recovery system. The results reveal that for the power generation systems with CO2 capture, the efficiency penalty not only affects the costs on fuel, but the incremental investment cost for CO2 capture (U.S.$,kW,1) as well. Consequently, it will have a decisive impact on the CO2 avoidance cost. Therefore, the added attention should be paid to improve the technical performance in order to reduce the efficiency penalty in energy system with CO2 capture and storage. Additionally, the system integration may not only decrease the efficiency penalty, but also simplify the system structure and keep the investment increment at a low level, and thereby it reduces the CO2 avoidance cost significantly. For example, for the novel partial gasification CO2 recovery system, owing to system integration, its efficiency can reach 42.2%, with 70% of CO2 capture, and its investment cost is only 87$,kW,1 higher than that of the reference IGCC system, thereby the CO2 avoidance cost is only 6.23$,t,1 CO2. The obtained results provide a comprehensive technical,economical analysis method for energy systems with CO2 capture useful for reducing the avoidance costs. Copyright © 2009 John Wiley & Sons, Ltd. [source] SLE, atherosclerosis and cardiovascular diseaseJOURNAL OF INTERNAL MEDICINE, Issue 6 2005J. FROSTEGÅRD Abstract. Atherosclerosis is an inflammatory disease and the major cause of cardiovascular disease (CVD) in general. Atherosclerotic plaques are characterized by the presence of activated immune competent cells, but antigens and underlying mechanisms causing this immune activation are not well defined. During recent years and with improved treatment of acute disease manifestations, it has become clear that the risk of CVD is very high in a prototypic autoimmune disease, systemic lupus erythematosus (SLE). SLE-related CVD and atherosclerosis are important clinical problems but may in addition also shed light on how immune reactions are related to premature atherosclerosis and atherothrombosis. A combination of traditional and nontraditional risk factors, including dyslipidaemia (and to a varying degree hypertension, diabetes and smoking), inflammation, antiphospholipid antibodies (aPL) and lipid oxidation are related to CVD in SLE. Premature atherosclerosis in some form leading to atherothrombosis is likely to be a major underlying mechanism, though distinctive features if any, of SLE-related atherosclerosis when compared with ,normal' atherosclerosis are not clear. One interesting possibility is that factors such as inflammation or aPL make atherosclerotic lesions in autoimmune disease more prone to rupture than in ,normal' atherosclerosis. Whether premature atherosclerosis is a general feature of SLE or only affects a subgroup of patients remains to be demonstrated. Treatment of SLE patients should also include a close monitoring of traditional risk factors for CVD. In addition, attention should also be paid to nontraditional risk factors such as inflammation and SLE-related factors such as aPL. Hopefully novel therapeutic principles will be developed that target the causes of the inflammation and immune reactions present in atherosclerotic lesions. [source] Combined hematopoietic and lentiviral gene-transfer therapies in newborn Twitcher mice reveal contemporaneous neurodegeneration and demyelination in Krabbe diseaseJOURNAL OF NEUROSCIENCE RESEARCH, Issue 8 2009F. Galbiati Abstract This study characterized the therapeutic benefits of combining hematogenous cell replacement with lentiviral-mediated gene transfer of galactosylceramidase (GALC) in Twitcher mice, a bona fide model for Krabbe disease. Bone marrow cells and GALC-lentiviral vectors were administered intravenously without any preconditioning to newborn Twitcher pups before postnatal day 2. Treated Twitchers survived up to 4 months of age. GALC activity remained less than 5% of normal values in the nervous system for the first 2 months after treatment and reached ,30% in long-term-surviving mice. Long-term reconstitution of GALC activity in the nervous system was provided primarily by infiltrating macrophages and to a lesser extent by direct lentiviral transduction of neural cells. Treated Twitchers had significant preservation of myelin, with a G-ratio (ratio of the axon diameter to the diameter of the myelinated fiber) in sciatic nerve myelin of 0.75 ± 0.08 compared with 0.85 ± 0.10 in untreated mutants. Although treated mutants had improved locomotor activities during their long-term survival, they died with symptoms of progressive neurological degeneration, indistinguishable from those seen in untreated Twitchers. Examination of long-lived Twitchers showed that treated mutants were not protected from developing degeneration of axons throughout the neuroaxis. These results suggest that GALC deficiency not only affects myelinating glia but also leads to neuronal dysfunction. The contemporaneous neuropathology might help to explain the limited efficacy of current gene and cell therapies. © 2009 Wiley-Liss, Inc. [source] Prediction of solvent effect on the reaction rate and endo/exo selectivity of a Diels,Alder reaction using molecular surface electrostatic potentialJOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 7 2003M. R. Gholami Abstract Molecular surface electrostatic potential was used to predict the solvent effect on the reaction rate, endo/exo selectivity and diastereomeric excess of a Diels,Alder reaction. It is shown that these quantities can be expressed in terms of molecular surface electrostatic potentials of solvents which are obtained computationally by the HF/6,31++G* procedure. Regression analyses and an experimental database are used to obtain analytical representation of rate constant, endo/exo selectivity and diastereomeric excess. The models obtained show that the hydrogen bond donor ability of solvents on the above mentioned properties is substantial, whereas solvophobicity only affects the reaction rate and endo/exo selectivity of the reaction. Copyright © 2003 John Wiley & Sons, Ltd. [source] An NB-LRR protein required for HR signalling mediated by both extra- and intracellular resistance proteinsTHE PLANT JOURNAL, Issue 1 2007Suzan H.E.J. Gabriëls Summary Tomato (Solanum lycopersicum) Cf resistance genes confer hypersensitive response (HR)-associated resistance to strains of the pathogenic fungus Cladosporium fulvum that express the matching avirulence (Avr) gene. Previously, we identified an Avr4 - responsive tomato (ART) gene that is required for Cf-4/Avr4 -induced HR in Nicotiana benthamiana as demonstrated by virus-induced gene silencing (VIGS). The gene encodes a CC-NB-LRR type resistance (R) protein analogue that we have designated NRC1 (NB-LRR protein required for HR-associated cell death 1). Here we describe that knock-down of NRC1 in tomato not only affects the Cf-4/Avr4 -induced HR but also compromises Cf-4- mediated resistance to C. fulvum. In addition, VIGS using NRC1 in N. benthamiana revealed that this protein is also required for the HR induced by the R proteins Cf-9, LeEix, Pto, Rx and Mi. Transient expression of NRC1D481V, which encodes a constitutively active NRC1 mutant protein, triggers an elicitor-independent HR. Subsequently, we transiently expressed this auto-activating protein in N. benthamiana silenced for genes known to be involved in HR signalling, thereby allowing NRC1 to be positioned in an HR signalling pathway. We found that NRC1 requires RAR1 and SGT1 to be functional, whereas it does not require NDR1 and EDS1. As the Cf-4 protein requires EDS1 for its function, we hypothesize that NRC1 functions downstream of EDS1. We also found that NRC1 acts upstream of a MAP kinase pathway. We conclude that Cf -mediated resistance signalling requires a downstream NB-LRR protein that also functions in cell death signalling pathways triggered by other R proteins. [source] FK506 is neuroprotective in a model of antiretroviral toxic neuropathyANNALS OF NEUROLOGY, Issue 1 2003MRCP, Sanjay C. Keswani MBBS Antiretroviral toxic neuropathy is the most common neurological complication of human immunodeficiency virus infection. This painful neuropathy not only affects the quality of life of human immunodeficiency virus,infected patients but also severely limits viral suppression strategies. We have developed an in vitro model of this toxic neuropathy to better understand the mechanism of neurotoxicity and to test potential neuroprotective compounds. We show that among the dideoxynucleosides, ddC appears to be the most neurotoxic, followed by ddI and then d4T. This reflects their potency in causing neuropathy. AZT, which does not cause a peripheral neuropathy in patients, does not cause significant neurotoxicity in our model. Furthermore, in this model, we show that the immunophilin ligand FK506 but not cyclosporin A prevents the development of neurotoxicity by ddC, as judged by amelioration of ddC-induced "neuritic pruning," neuronal mitochondrial depolarization, and neuronal necrotic death. This finding suggests a calcineurin-independent mechanism of neuroprotection. As calcineurin inhibition underlies the immunosuppressive properties of these clinically used immunophilin ligands, this holds promise for the neuroprotective efficacy of nonimmunosuppressive analogs of FK506 in the prevention or treatment of antiretroviral toxic neuropathy. Ann Neurol 2003;53:000,000 [source] Controllable Synthesis of Nickel Hydroxide and Porous Nickel Oxide Nanostructures with Different MorphologiesCHEMISTRY - A EUROPEAN JOURNAL, Issue 16 2008Lihong Dong Dr. Abstract ,-Ni(OH)2 nanobelts, nanowires, short nanowires, and ,-Ni(OH)2 nanoplates have been successfully prepared in high yields and purities by a convenient hydrothermal method under mild conditions from very simple systems composed only of NaOH, NiSO4, and water. It has been found that the ratio of NaOH to NiSO4 not only affects the morphology of the Ni(OH)2 nanostructures, but also determines whether the product is of the ,- or ,-crystal phase. A notable finding is that porous NiO nanobelts were produced after exposure of the Ni(OH)2 products to an electron beam for several minutes during transmission electron microscopy (TEM) observations. Another unusual feature is that rectangular nanoplates with many gaps were obtained. Furthermore, porous NiO nanobelts, nanowires, and nanoplates could also be obtained by annealing the as-prepared Ni(OH)2 products. A sequence of dissolution, recrystallization, and oriented attachment-assisted self-assembly of nanowires into nanobelts is proposed as a plausible mechanistic interpretation for the formation of the observed structures. The method presented here possesses several advantages, including high yields, high purities, low cost, and environmental benignity. It might feasibly be scaled-up for industrial mass production. [source] | |||||||||||||||||||