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Terms modified by Weaker Selected AbstractsPerception of sweet taste is important for voluntary alcohol consumption in miceGENES, BRAIN AND BEHAVIOR, Issue 1 2008Y. A. Blednov To directly evaluate the association between taste perception and alcohol intake, we used three different mutant mice, each lacking a gene expressed in taste buds and critical to taste transduction: ,-gustducin (Gnat3), Tas1r3 or Trpm5. Null mutant mice lacking any of these three genes showed lower preference score for alcohol and consumed less alcohol in a two-bottle choice test, as compared with wild-type littermates. These null mice also showed lower preference score for saccharin solutions than did wild-type littermates. In contrast, avoidance of quinine solutions was less in Gnat3 or Trpm5 knockout mice than in wild-type mice, whereas Tas1r3 null mice were not different from wild type in their response to quinine solutions. There were no differences in null vs. wild-type mice in their consumption of sodium chloride solutions. To determine the cause for reduction of ethanol intake, we studied other ethanol-induced behaviors known to be related to alcohol consumption. There were no differences between null and wild-type mice in ethanol-induced loss of righting reflex, severity of acute ethanol withdrawal or conditioned place preference for ethanol. Weaker conditioned taste aversion (CTA) to alcohol in null mice may have been caused by weaker rewarding value of the conditioned stimulus (saccharin). When saccharin was replaced by sodium chloride, no differences in CTA to alcohol between knockout and wild-type mice were seen. Thus, deletion of any one of three different genes involved in detection of sweet taste leads to a substantial reduction of alcohol intake without any changes in pharmacological actions of ethanol. [source] Sensitivity of the southern African circulation to dipole sea-surface temperature patterns in the south Indian OceanINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 4 2002C. J. C. Reason Abstract Previous observational work suggests that when sea-surface temperature (SST) is warm (cool) in the southwest Indian Ocean and cool (warm) in the southeast Indian Ocean, increased (decreased) summer rains may occur over large areas of southeastern Africa. In this study, an atmospheric general circulation model is used to investigate the sensitivity of the regional circulation and rainfall over southern Africa to these dipole SST anomalies in the subtropical south Indian Ocean. When the model is forced with positive SST anomalies in the west and negative SST anomalies in the east, increased rainfall occurs over southeastern Africa as a result of the enhanced convergence of moister than average air over the region. Enhanced evaporation occurs over the warm pole in the southwest Indian Ocean and this moist air is advected towards southeastern Africa as a result of the low-pressure anomaly generated over this pole, which strengthens the onshore flow. Increased and more intense extra-tropical cyclones occur to the southeast of South Africa, favourable for tropical,temperate trough formation. When the SST poles are reversed in sign, decreased precipitation occurs over southeastern Africa as a result of increased low-level divergence of low-level flow and this flow being drier than average. Weaker and fewer extra-tropical cyclones occur southeast of South Africa in this case. The model results are sensitive to the proximity of the southwest Indian Ocean pole to southeastern Africa. There is also sensitivity in the model low-level wind changes and precipitation anomaly over low-latitude southern Africa (but not over South Africa to any significant extent) to the presence or absence of the SST pole over the southeast Indian Ocean. Although the model resolution does not capture the details of the local SST and topographic gradients as well as one would like, the changes in model circulation and precipitation in the experiments with different SST anomalies are consistent with previous observational and theoretical work, hence increasing confidence in the robustness of the results. Copyright © 2002 Royal Meteorological Society [source] A Nationwide Assessment of the Biodiversity Value of Uganda's Important Bird Areas NetworkCONSERVATION BIOLOGY, Issue 1 2006HERBERT TUSHABE AIAs; complementariedad; congruencia trans-taxón; selección de sitios de conservación Abstract:,BirdLife International's Important Bird Areas (IBA) program is the most developed global system for identifying sites of conservation priority. There have been few assessments, however, of the conservation value of IBAs for nonavian taxa. We combined past data with extensive new survey results for Uganda's IBAs in the most comprehensive assessment to date of the wider biodiversity value of a tropical country's IBA network. The combined data set included more than 35,000 site × species records for birds, butterflies, and woody plants at 86 Ugandan sites (23,400 km2), including 29 of the country's 30 IBAs, with data on additional taxa for many sites. Uganda's IBAs contained at least 70% of the country's butterfly and woody plant species, 86% of its dragonflies and 97% of its birds. They also included 21 of Uganda's 22 major vegetation types. For butterflies, dragonflies, and some families of plants assessed, species of high conservation concern were well represented (less so for the latter). The IBAs successfully represented wider biodiversity largely because many have distinctive avifaunas and, as shown by high cross-taxon congruence in complementarity, such sites tended to be distinctive for other groups too. Cross-taxon congruence in overall species richness was weaker and mainly associated with differences in site size. When compared with alternative sets of sites selected using complementarity-based, area-based, or random site-selection algorithms, the IBA network was efficient in terms of the number of sites required to represent species but inefficient in terms of total area. This was mainly because IBA selection considers factors other than area, however, which probably improves both the cost-effectiveness of the network and the persistence of represented species. Resumen:,El programa de Áreas de Importancia para las Aves (AIAs) de Birdlife International es el sistema global más desarrollado para la identificación de sitios de prioridad para la conservación. Sin embargo, ha habido pocas evaluaciones del valor de conservación de las AIAs para taxa no aviares. En la evaluación más integral, hasta la fecha, del valor de la biodiversidad en general de la red de AIAs de un país tropical, combinamos datos antiguos con los resultados de muestreos extensivos recientes de las AIAs de Uganda. El conjunto de datos combinados incluyó más de 35000 registros de sitios x especies de aves, mariposas y plantas leñosas en 86 sitios en Uganda (23400 km2), incluyendo 29 de las 30 AIAs del país, con datos sobre taxa adicionales en muchos sitios. Las AIAs de Uganda contenían por lo menos un 70% de las especies de mariposas y plantas leñosas del país, 86% de sus libélulas y 97% de sus aves. También incluyeron 21 de los 22 principales tipos de vegetación. En las mariposas, libélulas y algunas de las familias de plantas evaluadas, la representación de especies de alto interés para la conservación fue buena (menor en las plantas). Las Áreas de Importancia para las Aves representaron exitosamente a la biodiversidad en general principalmente porque muchas tienen avifaunas distintivas y, como muestra la alta congruencia trans-taxón en complementariedad, tales sitios tendieron a ser distintivos para otros grupos también. La congruencia trans-taxón en la riqueza de especies total fue más débil y se asoció principalmente con diferencias en el tamaño del sitio. Cuando se compara con conjuntos alternativos de sitios seleccionados mediante algoritmos basados en complementariedad, área o selección aleatoria de sitios, la red de AIAs fue eficiente en términos del número de sitios requeridos para representar especies, pero ineficiente en términos del área total. Sin embargo, esto se debió principalmente a que la selección de AIA considera factores distintos al área que probablemente mejoran tanto la efectividad de la red como la persistencia de las especies representadas. [source] P72 Pigmented patch-test substance and laser Doppler perfusion imagingCONTACT DERMATITIS, Issue 3 2004Bolli Bjarnason Objective:, To investigate if pigment of a dark patch-test substance may affect assessment of perfusion with the laser Doppler imaging technique. Materials:, 13 subjects who previously patch-tested positive with 25% balsam of Peru in petrolatum were re-tested with the same test substance and petrolatum controls applied directly by transparent foils and with much weaker and less pigmented serial doses tested with polyester squares. Readings of perfusion were performed through the test substances and the transparent foils at time intervals up to 4 days while tests were applied and for 5 days following detachment of tests. The instrument set-up of the LDPI was the same as we have suggested for non-pigmented patch-test substances tested on white skin. Results:, Results show that pigment remnants following detachment of the dark pigmented and pasty test substance containing the petrolatum vehicle were prone to affect perfusion assessments by masking detection of perfusion of parts of test sites. A real masking effect is supported by a similar effect with readings of the same tests while they were applied and by no such observable effect with the petrolatum controls or the non-pasty and much less pigmented squares. Conclusion:, The results show that pigment of patch-test substances may affect perfusion assessments with the instrument set-up suggested for non-pigmented substances. [source] Discretionary Accounting Accruals, Managers' Incentives, and Audit Fees,CONTEMPORARY ACCOUNTING RESEARCH, Issue 3 2003Ferdinand A. Gul Abstract This paper examines the linkages between discretionary accruals (DAs), managerial share ownership, management compensation, and audit fees. It draws on the theory that managers of firms with high management ownership are likely to use DAs to communicate value-relevant information, while managers of firms with high accounting-based compensation are likely to use DAs opportunistically to manage earnings to improve their compensation. OLS regression results of 648 Australian firms show that (1) there is a positive association between DAs and audit fees; (2) managerial ownership negatively affects the positive relationship between DAs and audit fees; and (3) this negative impact is further found to be weaker for firms with high accounting-based management compensation. [source] The Association Between Web-Based Corporate Performance Disclosure and Financial Analyst Behaviour Under Different Governance RegimesCORPORATE GOVERNANCE, Issue 6 2007Walter Aerts In this study, we assert and test that the determination of corporate performance communication and financial analysts' earnings forecasting work are closely intertwined processes. The resulting endogeneity in capital markets' information dissemination and use is strongly influenced by a country's governance regime. Results from simultaneous equation regressions show significant interrelationships between financial analysts' activities and corporate disclosure transparency for North American firms. Moreover, analyst following underlies corporate disclosure, which ultimately leads to a reduction in the dispersion of analysts' earnings forecasts. In contrast, capital markets' information dynamics for continental European firms are much weaker. [source] AN ACOUSTIC REGISTER, TENACIOUS IMAGES, AND CONGOLESE SCENES OF RAPE AND REPETITIONCULTURAL ANTHROPOLOGY, Issue 2 2008NANCY ROSE HUNT ABSTRACT This article argues for the importance of rewriting the conventional atrocity narrative about violence in King Leopold's Congo Free State in relation to the present, the ongoing war-related humanitarianism and sexual violence in the DRC. The central idea is to push beyond the shock and tenacity of the visual, the ubiquitous mutilation photographs that tend to blot out all else; and instead seek weaker, more fragile acoustic traces in a diverse archive with Congolese words and sounds. This sensory, nonspectral mode of parsing the archive tells us something new about the immediacy of violence, its duration in memory, and the bodily and reproductive effects of sexually torturing women. The sound of twisted laughter convulsed around forms of sexual violence that were constitutive of reproductive ruination during the rubber regime in Leopold's Congo. The work of strategically tethering the past to the present should not be about forging historicist links across time but about locating repetitions and difference, including differences among humanitarian modes and strategies in the early 20th and the early 21st centuries. [source] Contribution of Na+/Ca2+ exchanger to the regulation of myogenic tone in isolated rat small arteriesACTA PHYSIOLOGICA, Issue 2 2001S. Horiguchi The contribution of the Na+/Ca2+ exchanger to the myogenic vascular tone was examined in rat isolated skeletal muscle small arteries (ASK) with pronounced myogenic tone and mesenteric small arteries (AMS) with little myogenic tone. Myogenic tone was assessed by the vascular inner diameter at transmural pressures of 40 and 100 mmHg. To depress the Na+/Ca2+ exchanger, the extracellular Na+ concentration ([Na+]o) was lowered from 143 to 1.2 mM by substituting choline-Cl for NaCl. The ASK developed significant myogenic tone and constricted further in low [Na+]o. Nifedipine (1 ,M) reduced both myogenic tone and low [Na+]o-induced contraction. Because the membrane potential of ASK was not changed by low [Na+]o (,35 ± 2 mV at 143 mM [Na+]o, ,37 ± 3 mV at 1.2 mM [Na+]o), depolarization-induced Ca2+ influx was not a cause of the low [Na+]o-induced contraction. The AMS did not develop significant myogenic tone. Although low [Na+]o also constricted AMS, the magnitude of constriction was significantly weaker than that in ASK (17 ± 4 vs. 47 ± 6%, P < 0.01, at 58 mM Na+). With Bay K 8644, AMS developed myogenic tone, and low [Na+]o-induced constriction was significantly increased. In conclusion, Na+/Ca2+ exchanger may play an important role in regulating myogenic tone, likely via mediating Ca2+ -extrusion. [source] Myotonic dystrophy: muscle involvement in relation to disease type and size of expanded CTG-repeat sequenceDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 7 2005Anna-Karin Kroksmark PT Msc This study aimed to: classify a cohort of children and adolescents with myotonic dystrophy (dystrophia myotonica: DM) into congenital and childhood onset forms; estimate CTG expansion size; and quantify muscle strength, contractures, and motor function in children with DM and compare results with those of controls. Participants were clinically examined, medical records were reviewed, and isometric muscle strength, contractures, and motor function were measured. Participants were: 42 children with DM (18 females, 24 males; mean age 8y 9mo [SD 4y 7mo], range 10mo to 17y) and 42 age- and sex-matched, healthy controls. Children with DM were divided into three groups: severe congenital (n=13), mild congenital (n=15), and childhood (n=14). Children with childhood DM were significantly weaker than controls (wrist and ankle dorsiflexors [p=0.0044, p=0.0044 respectively]; hip abductors and flexors [p=0.0464, p=0.0217]; and knee flexors and extensors: [p=0.0382, p=0.0033]). Children with mild congenital DM were significantly weaker than controls in all assessed muscle groups Contractures and skeletal deformities were more frequent at time of investigation than at birth, suggesting that foot and spine deformities in particular increase over time. Motor function score was significantly lower for children with DM than for controls. Children with severe congenital DM had the lowest motor function, with correlation between motor function and size of CTG repeat (p=-0.743). Children found jumping, heel standing, and head lifting the most difficult items to perform but few had difficulty walking, running, or stair climbing. DM in children is a heterogeneous disorder with a wide spectrum of muscle involvement, and owing to increased risk of contractures and skeletal deformities, regular follow-ups are recommended. [source] Children's working understanding of the knowledge gained from seeing and feelingDEVELOPMENTAL SCIENCE, Issue 2 2008E.J. Robinson In three experiments (N = 48 3- to 4-year olds; 100 3- to 5-year olds; 54 4-year-olds), children who could see or feel a target toy, recognized when they had sufficient information to answer ,Which one is it?' and when they needed additional access. They were weaker at taking the informative modality of access when the choice was between seeing more of a partially visible toy and feeling it; at doing so when the target was completely hidden; and at reporting seeing or feeling as their source of knowledge of the target's identity having experienced both. Working understanding of the knowledge gained from seeing and feeling (identifying the target efficiently) was not necessarily in advance of explicit understanding (reporting the informative source). [source] Plasma lipids and urinary albumin excretion rate in Type 1 diabetes mellitus: the EURODIAB IDDM Complications StudyDIABETIC MEDICINE, Issue 1 2001M. B. Mattock SUMMARY Aims To examine the relationship between increased urinary albumin excretion rate and fasting plasma lipids among male and female respondents to the EURODIAB IDDM Complications Study, and attempt to explain inconsistencies in previous reports. Methods A cross-sectional study of 3250 randomly selected Type 1 diabetic patients from 31 diabetes clinics in 16 European countries was carried out between 1989 and 1990. Plasma lipids and urinary albumin were measured centrally. The present analysis was confined to the subgroup of 2205 patients attending after a 10,12 h overnight fast. Mean age was 33 years (sd 10) and mean duration of Type 1 diabetes mellitus was 15 years (sd 9). Results The prevalence of microalbuminuria (24-h urinary albumin excretion rate 20,200 ,g/min) was 21.7% (95% confidence interval 19.9,23.5) and macroalbuminuria (24-h urinary albumin excretion rate >,200 ,g/min) 7.8% (6.6,9.0). In comparison to patients with normal urinary albumin excretion rate (< 20 ,g/min), and after controlling for age, sex, glycaemic control, duration of diabetes and current smoking, macroalbuminuria was associated with significantly (P < 0.01) increased fasting plasma triglycerides, cholesterol, LDL-cholesterol, cholesterol:HDL-cholesterol ratio and, in women, reduced HDL-cholesterol. In men and women with microalbuminuria, the only significant association was with increased plasma triglycerides. Conclusions These data confirm that there is an association between fasting plasma lipids and increasing urinary albumin excretion rate in European Type 1 diabetic patients. In microalbuminuric patients, however, the association was weaker than previously reported and partly explained by confounding factors. [source] Spatial congruence between ecotones and range-restricted species: implications for conservation biogeography at the sub-continental scaleDIVERSITY AND DISTRIBUTIONS, Issue 3 2009Berndt J. Van Rensburg ABSTRACT Aim, To examine whether at a sub-continental scale range-limited species tend to occur close to areas of transition between vegetation boundaries more often than expected by chance. Location, South Africa and Lesotho. Methods, We examined the relationship between the distance of a grid square to ecological transition areas between vegetation types and both avian and frog range-limited species richness in the quadrat. We used quadrats at a spatial resolution of quarter degree (15, × 15,, 676 km2). Spatial congruence between areas representing range-restricted species and those representing ecological transition zones was assessed using a random draw technique. Results, Species richness and range size rarity are generally negatively correlated with distance to transition areas between vegetation communities when analysed for the whole region for both groups. Although this relationship becomes weaker after controlling for environmental energy and topographical heterogeneity, the explanatory power of distance to transition areas remains significant, and compared to the different biomes examined, accounts for most of the variation in bird richness (20%), frog richness (18%), range-restricted bird species (17%) and range-restricted frog species (16%) in the savanna biome. The random draw technique indicated that areas representing range-restricted species were situated significantly closer in space to those areas representing transition areas between vegetation communities than expected by chance. Main conclusions, We find that at the sub-continental scale, when examined for South Africa, areas of transition between vegetation communities hold concentrations of range-limited species in both birds and frogs. We find that South African endemic/range-limited birds and frogs are located closer to ecological transition zones than endemics and non-endemics combined. This has important implications for ongoing conservation planning in a biogeographical context. [source] Morphometric controls and geomorphic responses on fans in the Southern Alps, New ZealandEARTH SURFACE PROCESSES AND LANDFORMS, Issue 3 2004Fes A. de Scally Abstract Morphometric variables associated with 41 debris-,ow and 18 ,uvial fans and their basins in the Southern Alps of New Zealand are examined. The results show statistically signi,cant differences in the area, maximum elevation, relief and ruggedness (Melton's R) of the basin and the area, gradient, and apex and toe elevations of the fan between debris-,ow and ,uvial sites. Concavity of the fan longitudinal pro,le also differs between the two fan types, although this could not be tested statistically. Most of these morphometric differences re,ect differences in processes and environmental controls on them. Discriminant analysis indicates that basin area and fan gradient best differentiate the two fan types by process. Moderately strong correlations exist, on both debris-,ow and ,uvial fans, between basin area or Melton's R and fan area. Correlations between basin area or Melton's R and fan gradient are generally weaker. The results of this study also indicate that on debris-,ow-prone fans the fan gradient and basin Melton's R have lower thresholds which overlap little with upper thresholds associated with basins where only stream,ow reaches the fan. These thresholds may therefore have value in preliminary morphometric assessments of debris-,ow hazard on fans in the Southern Alps. Copyright © 2004 John Wiley & Sons, Ltd. [source] Comparison of Tissue Doppler Velocities Obtained by Different Types of Echocardiography Systems: Are They Compatible?ECHOCARDIOGRAPHY, Issue 3 2010Mónika Dénes M.D. Background: Both systolic and diastolic tissue Doppler (TD) velocities have an important diagnostic and prognostic role in cardiology. We aimed to compare TD velocities between two different echocardiography systems. Patients: Thirty-one consecutive patients (mean age: 65.2 ± 17.5 years; 12 males) were enrolled. Methods: Systolic (Sa), early (Ea), and late (Aa) diastolic velocities were measured by TD at the lateral mitral annulus by a Sonos 2000 (Hewlett-Packard, Andover, MA, USA) and a Philips iE33 system. The E/Ea ratio was calculated. Results: Ea, Aa, and Sa velocities were higher when measured by the Sonos system (Ea: 13.2 ± 4.1 cm/s vs. 8.3 ± 3.6 cm/s; Aa: 14.8 ± 3.8 cm/s vs. 9.3 ± 2.3 cm/s; Sa: 15.2 ± 3.6 cm/s vs. 8.4 ± 2.0 cm/s; P < 0.0001 all). A significant correlation was found in Ea and in Ea/Aa (r = 0.84 and r = 0.85 resp; P < 0.0001 for both), and a weaker in Aa (r = 0.43; P = 0.02) between the machines. The Bland-Altman analysis showed broad limits of agreement between the measurements for Ea, Aa, and Sa (mean difference: 4.95 cm/s; 5.52 cm/s; 6.73 cm/s, respectively; limits: 0.64,9.25 cm/s; ,1.39,12.39 cm/s; ,0.37,13.83 cm/s, respectively). An E/Ea ratio >5.6 by the Sonos system showed 75% sensitivity and 79% specificity for elevated left ventricular filling pressure, defined as E/Ea >10 by the reference Philips system. Conclusions: Although diastolic TD velocities had excellent correlations between the two machines, there was a systematic overestimation by the Sonos system. Since the limits of agreement do not allow replacing the measurements, we suggest using the same echocardiographic equipment at patient follow-up. (Echocardiography 2010;27:230-235) [source] Community effects of praying mantids: a meta-analysis of the influences of species identity and experimental designECOLOGICAL ENTOMOLOGY, Issue 4 2002William F. Fagan Abstract ,1. Generalist arthropod predators are ubiquitous in terrestrial ecosystems but experimental studies have yielded little agreement as to their effects on prey assemblages. Drawing on results from a suite of experimental field studies, a meta-analysis was conducted of the impact of praying mantids (Mantodea: Mantidae) on arthropod assemblages in order to identify predictable and unpredictable effects of these extremely generalised predators. 2. Results across different experiments were synthesised using the log response ratio framework, with a focus on quantifying net mantid impacts on arthropod density across taxonomic orders and trophic levels of arthropods, paying special attention to the contribution of mantid species identity and experimental design variables, such as the use of cages, length of experiment, and manipulated mantid density. 3. Calculated on a per mantid-day basis, the net impacts of Tenodera sinensis on arthropod density were generally weaker but more predictable than the effects of Mantis religiosa. Mantids in general had weak negative effects on density for most taxa but exhibited strong negative and positive effects on some taxa. Tenodera sinensis tended to have negative effects on Homoptera, Diptera, and Hemiptera and herbivores as a group, however M. religiosa exhibited greater variation in response of different taxa that appeared to be affected more strongly by experimental design. The effects of Stagmomantis carolina tended to be negative or non-significant. 4. Experimental cages had little influence on either the sign or magnitude of net community impacts for T. sinensis, however cage experiments reversed the sign of the mean effect for two of six taxonomic orders when the experimental predator was M. religiosa. Cages also increased the variability of effect size greatly for M. religiosa but not for T. sinensis. 5. It was concluded that it is possible to use log response ratios to determine general, predictable trends in a well-studied system. Similar meta-analyses of generalist predator effects in other systems should produce predictions of how these predators influence food webs, an important step towards defining more clearly the influences of generalist predators on community structure and dynamics. [source] Cascading effects of variation in plant vigour on the relative performance of insect herbivores and their parasitoidsECOLOGICAL ENTOMOLOGY, Issue 1 2002Tiit Teder Abstract 1. Consequences of variation in food plant quality were estimated for a system consisting of two monophagous noctuid herbivores and three ichneumonid parasitoids. 2. In a natural population, pupal weights of the herbivores in this system, Nonagria typhae and Archanara sparganii, were found to be highly variable. Pupal weights increased strongly and consistently with the increase in the vigour of the host plant, Typha latifolia, providing support for the plant vigour hypothesis. Correspondingly, as the moths do not feed as adults, a strong, positive correlation between host vigour and fecundity of the herbivores would be expected. 3. There were strong and positive relationships between adult body sizes of the parasitoids and the sizes of their lepidopteran hosts. Moreover, a direct, positive link between plant quality and parasitoid size was documented. 4. For all three parasitoids, cascading effects of plant quality on body size were weaker than for the herbivores. Differences in the importance of adult feeding and oviposition behaviour suggest that dependence of fitness on body size is also weaker in the parasitoids than in the moths. It is therefore concluded that the numerical response of the herbivore population to a change in plant quality should exceed the corresponding response in the parasitoids. 5. The results of this work imply that variation in plant variables may affect performance of different trophic levels to a different extent. It is suggested that the importance of adult feeding for the reproductive success (capital vs. income breeding strategies) in both herbivores and parasitoids is an essential aspect to consider when predicting responses of such a system to changes in plant quality. [source] Fitness and body size in mature odonatesECOLOGICAL ENTOMOLOGY, Issue 2 2000Natalia Sokolovska Summary The relationship between body size and fitness components in odonates was examined using a meta-analysis of 33 published studies. There was a positive and significant overall effect of body size on mating rate and lifetime mating success among males. There was also a weaker but still significant positive effect of body size on survivorship of males. The relationship between body size, mating rate, longevity, and lifetime mating success differed significantly between males of territorial and nonterritorial species. The effect of body size was significant for all fitness components in territorial species but significant only for longevity and lifetime mating success in nonterritorial species. Effect sizes appeared to be strongest on longevity in both sexes, and on male mating rate in territorial species. Other effect sizes, even when significant, were small. Despite a much smaller data set, female fitness also increased significantly with body size. Both clutch size and longevity showed a significant positive relationship with body size. These results suggest that there is a general fitness benefit to large size in odonates. Nevertheless, significant heterogeneity is apparent in this effect, which can be attributed to sex, mating system, and fitness component. Finally, these analyses point to inadequacies in the current data that need further study before the potentially rich patterns in size effects on fitness can be explored more thoroughly. [source] Operational sex ratio, sexual conflict and the intensity of sexual selectionECOLOGY LETTERS, Issue 5 2008Patrick S. Fitze Abstract Modern sexual selection theory indicates that reproductive costs rather than the operational sex ratio predict the intensity of sexual selection. We investigated sexual selection in the polygynandrous common lizard Lacerta vivipara. This species shows male aggression, causing high mating costs for females when adult sex ratios (ASR) are male-biased. We manipulated ASR in 12 experimental populations and quantified the intensity of sexual selection based on the relationship between reproductive success and body size. In sharp contrast to classical sexual selection theory predictions, positive directional sexual selection on male size was stronger and positive directional selection on female size weaker in female-biased populations than in male-biased populations. Thus, consistent with modern theory, directional sexual selection on male size was weaker in populations with higher female mating costs. This suggests that the costs of breeding, but not the operational sex ratio, correctly predicted the strength of sexual selection. [source] Evidence for the effectiveness of sterile injecting equipment provision in preventing hepatitis C and human immunodeficiency virus transmission among injecting drug users: a review of reviewsADDICTION, Issue 5 2010Norah Palmateer ABSTRACT Aims To review the evidence on the effectiveness of harm reduction interventions involving the provision of sterile injecting equipment in the prevention of hepatitis C virus (HCV) and human immunodeficiency virus (HIV) transmission among injecting drug users (IDUs). The interventions assessed were needle and syringe programmes (NSP), alternative modes of needle/syringe provision (pharmacies, vending machines and outreach) and the provision of injecting equipment other than needles/syringes. Methods Systematic searches of the English language literature to March 2007 were undertaken to identify systematic, narrative or meta-analytical reviews (also known as a review of reviews) of the impact of interventions on HCV transmission, HIV transmission or injecting risk behaviour (IRB). Critical appraisal criteria classified the reviews as either high quality (,core') or supplementary: a framework based on the quality of reviews, the reviewers' conclusions and the designs/findings of the primary studies was used to derive evidence statements. Results Three core and two supplementary reviews of injecting equipment interventions were identified. According to the proposed framework, this study found (a) insufficient evidence to conclude that any of the interventions are effective in preventing HCV transmission; (b) tentative evidence to support the effectiveness of NSP in preventing HIV transmission; (c) sufficient evidence to support the effectiveness of NSP (and tentative evidence of an additional impact of pharmacy NSP) in reducing self-reported IRB; and (d) little to no evidence on vending machines, outreach or providing other injecting equipment in relation to any of the outcomes. Conclusions The evidence is weaker than given credit for in the literature. The lack of evidence for effectiveness of NSP vis-à-vis biological outcomes (HCV and HIV incidence/prevalence) reflects the limitations of studies that have been undertaken to investigate these associations. Particularly for HCV, low levels of IRB may be insufficient to reduce high levels of transmission. New studies are required to identify the intervention coverage necessary to achieve sustained changes in blood-borne virus transmission. [source] THE OPTIMAL PUBLIC EXPENDITURE FINANCING POLICY: DOES THE LEVEL OF ECONOMIC DEVELOPMENT MATTER?ECONOMIC INQUIRY, Issue 3 2007NILOY BOSE This paper explores how the optimal mode of public finance depends on the level of economic development. The theoretical analysis suggests that in the presence of capital market imperfection and liquidity shocks, the detrimental effect of inflation on growth is stronger (weaker) at lower (higher) levels of economic development. Consequently, income taxation (seigniorage) is a relatively less distortionary way of financing public expenditure for low-income (high-income) countries. We provide empirical support for our model's predictions using a panel of 21 Organization for Economic Cooperation and Development countries and 40 developing countries observed over the period 1972,1999. (JEL E44, E6, H6, O42) [source] Alcohol consumption and liver cirrhosis mortality with and without mention of alcohol,the case of CanadaADDICTION, Issue 9 2003Mats Ramstedt ABSTRACT Aims, To analyse post-war variations in per capita alcohol consumption in relation to gender-specific liver cirrhosis mortality in Canadian provinces and to assess the extent to which alcohol bears a different relation to cirrhosis deaths with mention of alcohol (alcoholic cirrhosis) compared to cirrhosis deaths without mention of alcohol (non-alcoholic cirrhosis). Data and method, Annual liver cirrhosis mortality rates by 5-year age groups were converted into gender-specific and age-adjusted mortality rates. Outcome measures included total cirrhosis,the conventional measure of liver cirrhosis,alcoholic cirrhosis and non-alcoholic cirrhosis. Per capita alcohol consumption was measured by alcohol sales and weighted with a 10-year distributed lag model. A graphical analysis was used to examine the regional relationship and the Box,Jenkins technique for time-series analysis was used to estimate the temporal relationship. Findings, Geographical variations in alcohol consumption corresponded to variations in total liver cirrhosis and particularly alcoholic cirrhosis, whereas non-alcoholic cirrhosis rates were not associated geographically with alcohol consumption. In general, for all provinces, time-series analyses revealed positive and statistically significant effects of changes in alcohol consumption on cirrhosis mortality. In Canada at large, a 1-litre increase in per capita consumption was associated with a 17% increase in male total cirrhosis rates and a 13% increase in female total cirrhosis rates. Alcohol consumption had a stronger impact on alcoholic cirrhosis, which increased by fully 30% per litre increase in alcohol per capita for men and women. Although the effect on the non-alcoholic cirrhosis rate was weaker (12% for men and 7% for women) it was nevertheless statistically significant and suggests that a large proportion of these deaths may actually be alcohol-related. Conclusions, Some well-established findings in alcohol research were confirmed by the Canadian experience: per capita alcohol consumption is related closely to death rates from liver cirrhosis and alcohol-related deaths tend to be under-reported in mortality statistics. [source] Performance and Policy of Foundation-owned Firms in GermanyEUROPEAN FINANCIAL MANAGEMENT, Issue 3 2002Markus Herrmann This paper compares performance and policy of foundation-owned firms and of listed corporations in Germany. Foundations have no owners so that there exist no individuals with financial ownership claims on firms which are wholly owned by foundations. This suggests weaker outside control of foundation-owned firms implying lower profitability. The empirical findings show a slightly better performance of foundation-owned firms compared to corporations. Foundation-owned firms display higher labour intensity, lower labour productivity, and lower salary levels. This policy promotes job security without endangering the viability of foundation-owned firms. [source] Peripheral T,cell tolerance occurs early during spontaneous prostate cancer development and can be rescued by dendritic cell immunizationEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 1 2005Elena Degl'Innocenti Abstract In the tumor-prone transgenic adenocarcinoma mouse prostate (TRAMP) mouse model we followed the fate of the immune response against the SV40 large T,antigen (Tag) selectively expressed in the prostate epithelium during the endogenous transformation from normal cells to tumors. Young (5,7-week-old) male TRAMP mice, despite a dim and patchy expression of Tag overlapping foci of mouse prostate intraepithelial neoplasia, displayed a strong Tag-specific cytotoxic T,lymphocyte (CTL) response after an intradermal injection of peptide-pulsed dendritic cells (DC). This response was weaker than the one found in vaccinated wild-type littermates, and was characterized by a reduced frequency and avidity of Tag-specific CTL. Early DC vaccination also subverted the profound state of peripheral tolerance typically found in TRAMP mice older than 9,10,weeks. The DC-induced CTL response indeed was still detectable in TRAMP mice of 16,weeks, and was associated with histology evidence of reduced disease progression. Our findings suggest that tumor antigens are handled as self antigens, and peripheral tolerance is associated with in situ antigen overexpression and cancer progression. Our data also support a relevant role for DC-based vaccines in controlling the induction of peripheral tolerance to tumor antigens. [source] The Role of Functionalisation, Asymmetry and Shape of a New Macrocyclic Compartmental Ligand in the Formation of Mononuclear, Homo- and Heterodinuclear Lanthanide(III) ComplexesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 1 2009Sergio Tamburini Abstract The compartmental [1+1] macrocycle H3L, obtained by self-condensation of the formyl precursor 3,3,-(3,6-dioxaoctane-1,8-diyldioxy)bis(2-hydroxybenzaldehyde) with the amine precursor N,N -bis(2-aminoethyl)-2-hydroxybenzylamine, contains one inner ON3O2 Schiff base and one outer O2O4 crown-like chamber. According to the experimental conditions it forms, by a template process, the stable mononuclear complexes Ln(H3L)(Cl)2(CH3COO)·nS·mHCl or [Ln(L)]·nS (Ln = La, Lu, Y, Yb, Er, Dy, Tb, Gd, Eu, Ce) with the lanthanide(III) ion encapsulated in the crown-ether-like and in the Schiff base site. The mononuclear complexes Ln(H3L)(Cl)2(CH3COO)·nS·mHCl, by further complexation with a different lanthanide(III) ion, give rise to the related heterodinuclear complexes [LnLn,(L)(Cl)2(CH3COO)]·nS while the homodinuclear and the heterodinuclear complexes [Ln2(L)](Cl)3·nH2O and [LnLn,(L)](Cl)3·nS could be prepared by a template reaction using the appropriate molar ratio of reactants. Their properties have been studied by using SEM-EDS microscopy, IR and NMR spectroscopy and their compositions confirmed by thermal and ESI-Mass spectrometric analyses. In the heterodinuclear complexes, the site occupancy of the different lanthanide(III) ions was determined by 1H and 13C NMR spectroscopy in CD3OD or (CD3)2SO , it was found that heterodinuclear complexation occurs in methanol with the smaller lanthanide(III) ion mainly coordinating to the Schiff base site and the larger lanthanide(III) ion to the crown site whereas, in dimethyl sulfoxide, demetalation of the weaker coordinated lanthanide(III) ion into the crown ether chamber occurs with the subsequent formation of mononuclear species in solution. The thermal decomposition of the heterodinuclear complexes forms the related mixed oxides, the stoichiometries and properties of which were determined by SEM-EDS microscopy and X-ray powder diffraction studies (XRD). (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Paucity of enkephalin production in neostriatal striosomal neurons: analysis with preproenkephalin,green fluorescent protein transgenic miceEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 10 2008Yoshinori Koshimizu Abstract Whether or not the striosome compartment of the neostriatum contained preproenkephalin (PPE)-expressing neurons remained unresolved. To address this question by developing a sensitive detection method, we generated transgenic mice expressing enhanced green fluorescent protein (GFP) under the specific transcriptional control of the PPE gene. Eight transgenic lines were established, and three of them showed GFP expression which was distributed in agreement with the reported localization of PPE mRNA in the central nervous system. Furthermore, in the matrix compartment of the neostriatum of the three lines, intense GFP immunoreactivity was densely distributed in the neuronal cell bodies and neuropil, and matrix neurons displayed > 94% co-localization for GFP and PPE immunoreactivities. In sharp contrast, GFP immunoreactivity was very weak in the striosome compartment, which was characterized by intense immunoreactivity for mu-opioid receptors (MOR). Although neostriatal neurons were divided into GFP-immunopositive and -negative groups in both the striosome and matrix compartments, GFP immunoreactivity of cell bodies was much weaker (,1/5) in GFP-positive striosomal neurons than in GFP-positive matrix neurons. A similar reciprocal organization of PPE and MOR expression was also suggested in the ventral striatum, because GFP immunoreactivity was weaker in intensely MOR-immunopositive regions than in the surrounding MOR-negative regions. As PPE-derived peptides are endogenous ligands for MOR in the neostriatum and few axon collaterals of matrix neurons enter the striosome compartment, the present results raised the question of the target of those peptides produced abundantly by matrix neurons. [source] GABA and glycine are protective to mature but toxic to immature rat cortical neurons under hypoxiaEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 2 2005Peng Zhao Abstract Although recent studies suggest that ,-aminobutyric acid (GABA) and glycine may be ,inhibitory' to mature neurons, but ,excitatory' to immature neurons under normoxia, it is unknown whether inhibitory neurotransmitters are differentially involved in neuronal response to hypoxia in immature and mature neurons. In the present study, we exposed rat cortical neurons to hypoxia (1% O2) and examined the effects of three major inhibitory neurotransmitters (GABA, glycine and taurine) on the hypoxic neurons at different neuronal ages [days in vitro (DIV)4,20]. Our data showed that the cortical neurons expressed both GABAA and glycine receptors with differential developmental profiles. GABA (10,2000 µm) was neuroprotective to hypoxic neurons of DIV20, but enhanced hypoxic injury in neurons of <,DIV20. Glycine at low concentrations (10,100 µm) exhibited a similar pattern to GABA. However, higher concentrations of glycine (1000,2000 µm) for long-term exposure (48,72 h) displayed neuroprotection at all ages (DIV4,20). Taurine (10,2000 µm), unlike GABA and glycine, displayed protection only in DIV4 neurons, and was slightly toxic to neurons >,DIV4. In comparison with delta-opioid receptor (DOR)-induced protection in DIV20 neurons exposed to 72 h of hypoxia, glycine-induced protection was weaker than that of DOR but stronger than that of GABA and taurine. These data suggest that the effects of the inhibitory neurotransmitters on hypoxic cortical neurons are age-dependent, with GABA and glycine being neurotoxic to immature neurons and neuroprotective to mature neurons. [source] Contribution of Kir3.1, Kir3.2A and Kir3.2C subunits to native G protein-gated inwardly rectifying potassium currents in cultured hippocampal neuronsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 8 2003Joanne L. Leaney Abstract G protein-gated inwardly rectifying potassium (GIRK) channels are found in neurons, atrial myocytes and neuroendocrine cells. A characteristic feature is their activation by stimulation of Gi/o -coupled receptors. In central neurons, for example, they are activated by adenosine and GABA and, as such, they play an important role in neurotransmitter-mediated regulation of membrane excitability. The channels are tetrameric assemblies of Kir3.x subunits (Kir3.1,3.4 plus splice variants). In this study I have attempted to identify the channel subunits which contribute to the native GIRK current recorded from primary cultured rat hippocampal pyramidal neurons. Reverse transcriptase,polymerase chain reaction revealed the expression of mRNA for Kir3.1, 3.2A, 3.2C and 3.3 subunits and confocal immunofluorescence microscopy was used to investigate their expression patterns. Diffuse staining was observed on both cell somata and dendrites for Kir3.1 and Kir3.2A yet that for Kir3.2C was weaker and punctate. Whole-cell patch clamp recordings were used to record GIRK currents from hippocampal pyramidal neurons which were identified on the basis of inward rectification, dependence of reversal potential on external potassium concentration and sensitivity to tertiapin. The GIRK currents were enhanced by the stimulation of a number of Gi/o -coupled receptors and were inhibited by pertussis toxin. In order to ascertain which Kir3.x subunits were responsible for the native GIRK current I compared the properties with those of the cloned Kir3.1 + 3.2A and Kir3.1 + 3.2C channels heterologously expressed in HEK293 cells. [source] The murine neurokinin NK1 receptor gene contributes to the adult hypoxic facilitation of ventilationEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2002Krzysztof Ptak Abstract Substance P and neurokinin-1 receptors (NK1) modulate the respiratory activity and are expressed early during development. We tested the hypothesis that NK1 receptors are involved in prenatal development of the respiratory network by comparing the resting respiratory activity and the respiratory response to hypoxia of control mice and mutant mice lacking the NK1 receptor (NK1,/,). In vitro and in vivo experiments were conducted on neonatal, young and adult mice from wild-type and NK1,/, strains. In the wild strain, immunohistological, pharmacological and electrophysiological studies showed that NK1 receptors were expressed within medullary respiratory areas prior to birth and that their activation at birth modulated central respiratory activity and the membrane properties of phrenic motoneurons. Both the membrane properties of phrenic motoneurons and the respiratory activity generated in vitro by brainstem-spinal cord preparation from NK1,/, neonate mice were similar to that from the wild strain. In addition, in vivo ventilation recordings by plethysmography did not reveal interstrain differences in resting breathing parameters. The facilitation of ventilation by short-lasting hypoxia was similar in wild and NK1,/, neonates but was significantly weaker in adult NK1,/, mice. Results demonstrate that NK1 receptors do appear to be necessary for a normal respiratory response to short-lasting hypoxia in the adult. However, NK1 receptors are not obligatory for the prenatal development of the respiratory network, for the production of the rhythm, or for the regulation of breathing by short-lasting hypoxia in neonates. [source] Mutation in hotfoot-4J mice results in retention of ,2 glutamate receptors in EREUROPEAN JOURNAL OF NEUROSCIENCE, Issue 8 2002Shinji Matsuda Abstract The orphan glutamate receptor ,2 is selectively expressed in Purkinje cells and plays a critical role in cerebellar function. Recently, the ataxia of hotfoot-4J (ho-4J) mice was shown to be caused by a 170,amino acid deletion in the N-terminal region of ,2 receptors. To understand ,2 receptor function, we characterized these mutant receptors (,2ho) in Purkinje cells. Immunohistochemical staining showed that ,2ho receptors of the ho-4J homozygotes were abundantly expressed but localized to the Purkinje cell soma; in wild-type mice, ,2 receptors were predominantly present at distal dendrites of Purkinje cells. In addition, ,2ho receptors of the ho-4J mice were sensitive to endoglycosidase H, a finding suggesting that ,2ho receptors were not transported beyond the endoplasmic reticulum (ER) or cis -Golgi apparatus. To gain further insights into the mechanisms of this phenomenon, we characterized ,2ho receptors in transfected HEK293 cells. ,2ho receptors expressed in HEK293 cells were also sensitive to endoglycosidase H. Immunohistochemical staining showed that ,2ho receptors colocalized with proteins retained in the ER. Furthermore, ,2ho receptors were not labelled by membrane-impermeable biotinylation reagents. Coimmunoprecipitation assays showed that the intermolecular interaction of ,2ho receptors was significantly weaker than those of wild-type ,2 receptors, a finding suggesting that the ho-4J region is involved in oligomerization of ,2 receptors. Thus, ,2ho receptors were retained in the ER, probably by the quality control mechanism that detects unstable oligomers. We conclude that the absence of ,2 receptors on the cell surface by failed transport from the ER of Purkinje cells causes ataxia. [source] Comparison of the aggregation properties, secondary structure and apoptotic effects of wild-type, Flemish and Dutch N-terminally truncated amyloid , peptidesEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 11 2001N. Demeester Abstract The Dutch (E22Q) and Flemish (A21G) mutations in the ,APP region of the amyloid precursor protein (APP) are associated with familial forms of Alzheimer dementia. However, patients with these mutations express substantially different clinical phenotypes. Therefore, secondary structure and cytotoxic effects of the three A,(12,42) variants [wild-type (WT), Dutch and Flemish] were tested. At a concentration of 5 µm the aggregation of these peptides followed the order: A,(1,42) WT > A,(12,42) WT > A,(12,42) Flemish >,A,(12,42) Dutch. The stability of the secondary structure of these peptides upon decreasing the trifluoroethanol (TFE) concentration in the buffer was followed by circular dichroism measurements. WT peptides progressively lost their ,-helical structure; this change occurred faster for both the Flemish and Dutch peptides, and at higher percentages of TFE in the buffer, and was accompanied by an increase in ,-sheet and random coil content. Apoptosis was induced in neuronal cells by the A,(12,42) WT and Flemish peptides at concentrations as low as 1,5 µm, as evidenced by propidium iodide (PI) staining, DNA laddering and caspase-3 activity measurements. Even when longer incubation times and higher peptide concentrations were applied the N-truncated Dutch peptide did not induce apoptosis. Apoptosis induced by the full length A,(1,42) peptide was weaker than that induced by its N-truncated variant. These data suggest that N-truncation enhanced the cytotoxic effects of A, WT and Flemish peptides, which may play a role in the accelerated progression of dementia. [source] | ||||||||||||||||||||||||||||||||||||||||||||||