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Kinds of Annual Terms modified by Annual Selected AbstractsQuality of poisoning management advice in the Monthly Index of Medical Specialties AnnualEMERGENCY MEDICINE AUSTRALASIA, Issue 5-6 2005James Mallows Abstract Background:, The Monthly Index of Medical Specialties (MIMS) contains Therapeutic Goods Administration-approved product information supplied by manufacturers. It is widely used by health-care professionals but is not specifically designed as a toxicology reference. Objectives:, To determine how widespread the use of MIMS is as a toxicology reference. To evaluate the quality of poisoning management advice it contains. Methods:, First, a survey of 500 consecutive calls to the NSW Poison Information Centre (PIC) was undertaken asking health-care workers which toxicology references were consulted prior to calling and which references they would use if the PIC were not available. Second, a consensus opinion for poisoning management was obtained, for 25 medications which are either commonly involved in poisoning or potentially life-threatening in overdose, by review of 5 current toxicology references for contraindicated treatments, ineffective treatments and specific recommended treatments and antidotes. MIMS poisoning management advice was then compared with this toxicology consensus opinion. Results:, In total, 276 doctors and 222 nurses were surveyed. Prior to calling the PIC 22.8% of doctors and 6.8% of nurses consulted MIMS. In total, 25.7% of doctors and 39.6% nurses stated they would use the MIMS for poisoning management advice if the PIC were not available. For the 25 drugs assessed, 14 contained inaccurate poisoning management: 1 recommended ineffective treatments and 14 omitted specific treatments or antidotes. Conclusion:, The MIMS is often used as a toxicology reference by physicians prior to calling the PIC. It contains a number of significant inaccuracies pertaining to management of poisonings and should not be used as a primary reference for poisoning advice. [source] Wading birds as bioindicators of mercury contamination in Florida, USA: Annual and geographic variationENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 1 2002Peter C. Frederick Abstract Mercury contamination in wetland biota is often dynamic, difficult to predict, and costly to track. In this paper, we present results from a six-year study of growing feathers of piscivorous birds as monitors of wetland Hg exposure in Florida, USA, wetlands. Between 1994 and 2000, we collected feathers of growing great egret (Ardea alba) nestlings from colonies in the freshwater Everglades of southern Florida, and during 1998, feathers were collected from chicks of both great egrets and white ibises (Eudocimus albus) at a variety of colonies throughout peninsular Florida. Coastal colonies showed significantly lower feather Hg concentrations than did inland sites. Within the Everglades, we found significant effects of both geographic location and year on age-adjusted mean total Hg concentrations in feathers. Over the course of our study, Everglades colonies maintained their Hg concentration rankings relative to one another, but all showed strongly declining Hg concentrations (mean of 73% averaged across colonies, between 1994 and 2000). Using a previously established predictive relationship between Hg consumption in food and feather Hg for great egrets, we estimated that Hg concentrations in the aggregate diet of egrets have been reduced by an average of 67%. We conclude that the Everglades has undergone a biologically significant decline in Hg availability in the wetland food web, possibly because of decreased local inputs. [source] Downslope Displacement Rates of Ploughing Boulders in A Mid-Alpine Environment: Finse, Southern Norway.GEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 3 2001Ivar Berthling Annual and seasonal displacements of ploughing boulders were investigated at Finse, southern Norway, by traditional surveying and differential carrier-phase global positioning system measurements. Annual displacement rates were mainly below 10 mm/year, although one particular season showed rates of 26 mm/year on average. There was a tendency for larger boulders to travel faster. Seasonal displacements were restricted to the annual freeze-thaw cycle. The frost heave seems to have a significant horizontal component, which does not necessarily point in the downslope direction. Thus, the concept of frost creep is not applicable to the investigated ploughing boulders. On the other hand, due to tilting of the boulders, a momentum may be gained during thaw consolidation that could induce downslope displacements. Such a process will work together with gelifluction. [source] Detection of trends in hydrological extremes for Canadian watershedsHYDROLOGICAL PROCESSES, Issue 13 2010Donald H. Burn Abstract The potential impacts of climate change can alter the risk to critical infrastructure resulting from changes to the frequency and magnitude of extreme events. As well, the natural environment is affected by the hydrologic regime, and changes in high flows or low flows can have negative impacts on ecosystems. This article examines the detection of trends in extreme hydrological events, both high and low flow events, for streamflow gauging stations in Canada. The trend analysis involves the application of the Mann,Kendall non-parametric test. A bootstrap resampling process has been used to determine the field significance of the trend results. A total of 68 gauging stations having a nominal record length of at least 50 years are analysed for two analysis periods of 50 and 40 years. The database of Canadian rivers investigated represents a diversity of hydrological conditions encompassing different extreme flow generating processes and reflects a national scale analysis of trends. The results reveal more trends than would be expected to occur by chance for most of the measures of extreme flow characteristics. Annual and spring maximum flows show decreasing trends in flow magnitude and decreasing trends in event timing (earlier events). Low flow magnitudes exhibit both decreasing and increasing trends. Copyright © 2010 John Wiley & Sons, Ltd. [source] Recent accumulation variability and change on the Antarctic Peninsula from the ERA40 reanalysisINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 11 2008Georgina M. Miles Abstract The Antarctic Peninsula has displayed significant climate change over recent decades. Understanding contemporaneous changes in accumulation is made difficult because the region's complex orography means that ice-core data are not necessarily representative of a wider area. In this paper, the patterns of regional spatial accumulation variability across the Antarctic Peninsula region are presented, based on an Empirical Orthogonal Function (EOF) analysis of European Centre for Medium Range Forecasts Reanalysis (ERA40) data over the 23-year period from 1979 through 2001. Annual and seasonal trends in the sign and strength of these patterns are identified, as is their relationship with mean sea level pressure, temperature and indices of large-scale circulation variability. The results reveal that the first pattern of accumulation variability on the Peninsula is primarily related to pressure in the circumpolar trough and the second pattern to temperature: together the two EOFs explain ,45,65% of the annual/seasonal accumulation. The strongest positive trend in an EOF occurs with EOF2 in the austral autumn March-April-May (MAM). This is highly correlated with the Southern Annular Mode (SAM) in this season, suggesting stronger westerly winds have caused an increase in orographic precipitation along the west Antarctic Peninsula. A significant correlation with ENSO occurs only in the winter EOF1, associated with blocking in the Bellingshausen Sea. Inter-annual ERA40 accumulation is shown to compare favourably with an ice core in the south of the Peninsula, but, for a variety of reasons, correlates poorly with accumulation as measured in an ice core from the northern tip. Opposite trends in accumulation at these two sites can be explained by the spatial pattern and trend of EOF2 in MAM and thus by recent changes in the SAM. The results of this study will aid in the understanding of temporal accumulation changes observed in the regional ice-core record. Copyright © 2007 Royal Meteorological Society [source] Climatology of cloud-to-ground lightning in Georgia, USA, 1992,2003INTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 15 2005Mace L. Bentley Abstract A 12-year climatology of lightning cloud-to-ground flash activity for Georgia revealed the existence of three primary regions of high lightning activity: the area surrounding the Atlanta Metropolitan Statistical Area, east-central Georgia along the fall line, and along the Atlantic coast. Over 8.2 million ground flashes were identified during the climatology. July was the most active lightning month and December was the least active. Annual, seasonal, and diurnal distributions of cloud-to-ground flashes were also examined. These patterns illustrated the interacting effects of land cover, topography, and convective instability in enhancing lightning activity throughout Georgia. A synoptic analysis of the ten highest lightning days during the summer and winter revealed the importance of frontal boundaries in organizing convection and high lightning activity during both seasons. The prominence of convective instability during the summer and strong dynamical forcing in the winter was also found to lead to outbreaks of high lightning activity. Copyright © 2005 Royal Meteorological Society. [source] Long-term effects of prescribed early fire, grazing and selective tree cutting on seedling populations in the Sudanian savanna of Burkina FasoAFRICAN JOURNAL OF ECOLOGY, Issue 1 2009Didier Zida Abstract Annual early fire, selective tree cutting and exclusion of grazing are currently used as management tools in the Sudanian savanna of Burkina Faso although their long-term effects on seedling recruitment are poorly documented. A factorial experiment involving fire, grazing and cutting, each with two levels, was established in 1992 to study the effects of these management regimes and their interactions on the regeneration of woody species, and examine whether their effects varied temporally. Species richness, density and the morphology of seedlings were assessed in 1997 and 2002, and their relative changes were determined. The change in species richness of multi-stemmed individuals was significantly higher (P = 0.018) on plots that received fire × cutting treatment than the control plots. Significantly more species with single-stem were found on unburnt than on burnt plots (P < 0.001). Grazing tended to reduce the change in total density while fire (P < 0.001) and grazing (P = 0.029) significantly reduced the change in density of single-stemmed individuals. Selective cutting did not affect the total seedling density, but tended to reduce the change in single-stemmed seedling density. Principal component analysis revealed species-specific responses to treatments, particularly the relatively high abundance of lianas compared with other species. Résumé Les feux annuels précoces, la coupe sélective d'arbres et l'exclusion du pâturage sont des moyens actuellement utilisés dans la gestion de la savane soudanienne du Burkina Faso, mais leurs effets à long terme sur le recrutement de jeunes plants sont encore mal documentés. Une expérience factorielle impliquant le feu, le pâturage et la coupe, chacun à deux niveaux, a été mis en place en 1992 pour étudier les effets de ces régimes de gestion et leurs interactions sur la régénération d'espèces ligneuses et pour voir si ces effets variaient de façon temporelle. La richesse spécifique, la densité et la morphologie des jeunes plants furent évaluées en 1997 et en 2002, et l'on a leurs changements relatifs déterminés. Le changement de la richesse spécifique des individus multicoles était significativement plus important (P = 0.018) dans les parcelles qui avaient subi le traitement feu × coupe que dans les parcelles témoins. On a trouvé significativement plus d'espèces à tige unique dans les parcelles non brûlées que dans les parcelles brûlées (P < 0.001). Le pâturage avait tendance à réduire le changement de densité totale alors que le feu (P < 0.001) et le pâturage (P = 0.029) réduisaient significativement le changement de densité des individus à tige unique. La coupe sélective n'affectait pas la densité totale des jeunes plants mais avait tendance à réduire le changement de la densité des plants à tige unique. L'analyse en composantes principales a révélé que les réponses aux différents traitements étaient spécifiques aux espèces, particulièrement l'abondance de lianes, relativement grande par rapport aux autres espèces. [source] Abundance and habitat segregation in Mediterranean grassland species: the importance of seed weightJOURNAL OF VEGETATION SCIENCE, Issue 2 2002F.M. Azcárate Castroviejo (1986,1999); except taxa yet to be covered which follow Tutin et al. (1964,1980) Abstract. We analysed the relationship between seed traits (weight, shape and dispersal structures) and the abundance and habitat segregation of Mediterranean grassland species. To take into account possible correlations with other plant traits, the study also includes 5 vegetative traits (growth form, plant longevity, clonality, onset of flowering and plant size) of commonly accepted functional importance. Data were recorded for 85 species from dehesa grasslands in central Spain. Species abundance was measured in upper (dry and less productive, high stress) and lower (moist and more productive, low stress) slope zones in the same area. Habitat segregation was estimated using an index based on the relative frequencies of species in upper and lower slope zones. Multiple regression models were fitted using species, as well as phylogenetically independent contrasts, as data points. Annual small-seeded species without specialised dispersal structures are over-represented in dehesa grasslands. Abundance was negatively related to seed weight in upper slope zones. None of the recorded plant traits were related to abundance in the lower slope zones. Habitat segregation was mainly related to seed weight, but also to some vegetative traits. Annual, early flowering and small-seeded species were relatively more abundant in the upper than the lower slope zones. This pattern is independent of phylogeny. Our results suggest that in dry Mediterranean grasslands, abundance of many species is determined by dispersal (production of numerous small seeds) rather than by competitive ability. [source] Seedbank phytosociology of the Strandveld Succulent Karoo, South Africa: a pre-mining benchmark survey for rehabilitationLAND DEGRADATION AND DEVELOPMENT, Issue 2 2001A. J. De Villiers Abstract Prior to the mining of heavy minerals, the seedbank of the Strandveld Succulent Karoo was investigated to serve as a benchmark for the future rehabilitation of the area. Seedbank composition and species' abundance were determined with the seedling emergence method. By using the Braun-Blanquet method, five main vegetation units were identified in concordance with results obtained for the standing vegetation. A total of 108 species were recorded in the seedbank, which represents c. 50 per cent of the species recorded in the standing vegetation of the total study area. Seven annual species (3 per cent) were unique to the soil seedbank. On community level, similarity in species composition between the standing vegetation and the soil seedbank ranged between 39·2 per cent and 48·8 per cent, with a similarity of 54·3 per cent for the total study area. Annual and perennial species' similarity in species composition between the standing vegetation and the seed bank totalled 74·8 per cent and 43·1 per cent respectively. Post-mining topsoil replacement as well as seeding and transplanting of selected local species will be essential to revegetate this area. Copyright © 2001 John Wiley & Sons, Ltd. [source] Influences of study design and location on the relationship between particulate matter air pollution and birthweightPAEDIATRIC & PERINATAL EPIDEMIOLOGY, Issue 3 2008Jennifer D. Parker Summary A large number of studies have identified a relationship between particulate matter air pollution and birthweight. Although reported associations are small and varied, they have been identified in studies from places around the world. Exposure assignment, covariates and study inclusion criteria vary among studies. To examine the effect of these and other study characteristics on associations between particulate matter and birthweight, US birth records for singletons delivered at 40 weeks gestation in 2001,03 during the months of March, June, September and December were linked to quarterly estimates of pollution exposure, both particulate matter exposure and exposure to multiple pollutants, by county of residence and month of birth. Annual, 9-month and trimester-specific exposures were assigned. Among births linked to particulate matter exposure there was a small association between coarse particle exposure and birthweight (beta ,13 g per 10 µg/m3 increase [95% CI ,18.3 g, ,7.6 g]) after controlling for maternal factors; this association was attenuated slightly and remained statistically significant after further adjustment for contextual factors, year of birth, region, or urban,rural status. The associations were slightly weaker among births linked to multiple pollutant exposure than among births linked to just particulate matter exposure. The association varied markedly by region, ranging from a decrement of 43 g per 10 µg/m3[95% CI ,58.6 g, ,27.6 g] in the north-west to a null association in the south-west. Trimester findings were smaller, yet remained significant and varied regionally. The association between fine particle exposure and birthweight varied considerably, with an overall small positive association that became null after control for region. This study found that wide regional differences in association may contribute to the varied published findings. The association between coarse particle exposure and birthweight appeared robust, if small; fine particles had no overall association with birthweight. [source] Increase in aspergillosis and severe mycotic infection in patients with leukemia and MDS: Comparison of the data from the Annual of the Pathological Autopsy Cases in Japan in 1989, 1993 and 1997PATHOLOGY INTERNATIONAL, Issue 11 2003Hikaru Kume To study the relationship between the changes in visceral mycoses rates and recently advanced medical care in hematological settings, data on visceral mycosis cases with leukemia and myelodysplastic syndrome (MDS) that had been reported in the Annual of the Pathological Autopsy Cases in Japan in 1989, 1993 and 1997 were analyzed. The frequency rate of visceral mycoses with leukemia and MDS was 27.9% (435/1557) in 1989, 23.0% (319/1388) in 1993 and 22.3% (246/1105) in 1997. In comparing the rate of mycoses in recipients of organ or bone marrow transplantation with that of non-recipients, that of recipients was approximately 10% higher. The predominant causative agents were Candida and Aspergillus, at approximately the same rate as in 1989. The rate of candidosis decreased to one-half that of aspergillosis by 1993. Furthermore, severe mycotic infections clearly increased from 58.9% in 1989 to 75.6% in 1997. Among a total of 1000 cases with mycotic infection in those 3 years, acute lymphatic leukemia and acute myeloid leukemia were the major diseases (40.6% and 34.8%, respectively), followed by MDS (26.1%). The reasons for increased rates of aspergillosis and of severe mycotic infection can be surmised to be: (i) candidosis had become controllable by prophylaxis and by empiric therapy for mycoses with effective antifungal drugs; (ii) the marketed antifungal drugs were not sufficiently effective against severe infections or Aspergillus infections; and (iii) the number of patients surviving in an immunocompromised state had increased due to developments in chemotherapy and progress in medical care. [source] Short but catching up: Statural growth among native Amazonian Bolivian childrenAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 3 2010Ricardo Godoy The ubiquity and consequences of childhood growth stunting (<,2 SD in height-for-age Z score, HAZ) in rural areas of low-income nations has galvanized research into the reversibility of stunting, but the shortage of panel data has hindered progress. Using panel data from a native Amazonian society of foragers-farmers in Bolivia (Tsimane'), we estimate rates of catch-up growth for stunted children. One hundred forty-six girls and 158 boys 2 , age , 7 were measured annually during 2002,2006. Annual , height in cm and in HAZ were regressed separately against baseline stunting and control variables related to attributes of the child, mother, household, and village. Children stunted at baseline had catch-up growth rates 0.11 SD/year higher than their nonstunted age and sex peers, with a higher rate among children farther from towns. The rate of catch up did not differ by the child's sex. A 10% rise in household income and an additional younger sibling lowered by 0.16 SD/year and 0.53 SD/year the rate of growth. Results were weaker when measuring , height in cm rather than in HAZ. Possible reasons for catch-up growth include (a) omitted variable bias, (b) parental reallocation of resources to redress growth faltering, particularly if parents perceive the benefits of redressing growth faltering for child school achievement, and (c) developmental plasticity during this period when growth rates are most rapid and linear growth trajectories have not yet canalized. Am. J. Hum. Biol., 2010. © 2009 Wiley-Liss, Inc. [source] DISTRIBUTIONAL CONFLICT, POLITICAL CYCLES AND GROWTHTHE MANCHESTER SCHOOL, Issue 4 2005CHRISTIANE CLEMENS This paper discusses the emergence of endogenous redistributive cycles in a stochastic growth model with incomplete asset markets and heterogeneous agents who vote on the degree of progressivity in the tax-transfer scheme. The model draws from Bénabou (in B. S. Bernanke and J. J. Rotemberg (eds), NBER Macroeconomics Annual, Vol. 11, Cambridge, MA, MIT Press, pp. 11,74) and ties the bias in the distribution of political power to the degree of inequality in the society, thereby triggering redistributive cycles which then give rise to a nonlinear, cyclical pattern of savings rates, growth and inequality over time. [source] Assessment of the severe weather environment in North America simulated by a global climate modelATMOSPHERIC SCIENCE LETTERS, Issue 4 2007Patrick T. Marsh Abstract Annual and seasonal cycles of convectively important atmospheric parameters for North America have been computed using the Community Climate System Model version 3 (CCSM3) Global Climate Model using a decade of CCSM3 data. Results for the spatial and temporal distributions of environments conducive to severe convective weather qualitatively agree with observational estimates from NCAR/NCEP global reanalyses, although the model underestimates the frequency of occurrence of severe weather environments. This result demonstrates the possibility for future studies aimed at determining possible changes in the distribution of severe weather environments associated with global climate change. Copyright © 2007 Royal Meteorological Society [source] Violent recidivism among mentally disordered offenders in JapanCRIMINAL BEHAVIOUR AND MENTAL HEALTH, Issue 3 2007Kazuo Yoshikawa Background,A new forensic mental health law was enacted in Japan in 2003, enabling development of specialist services. Before their establishment, it is important to determine the nature, frequency and correlates of the problems they are designed to ameliorate. Aims,To establish rates of violent recidivism among mentally disordered offenders before the new legislation, and examine associated risk factors. Method,Data were extracted from one complete annual (1980) national cohort of people judged by the Court or prosecutor to be without responsibility for a criminal offence, or of sufficiently diminished responsibility for it to be diverted for psychiatric treatment. The outcome measure was violent recidivism after community discharge and before 1991. Results,Fifty-two (10%) of 489 in the cohort were arrested or convicted of further violent offences. Violent recidivism was most strongly associated with a substance-related disorder, but histories of violence, homelessness and short index admissions were independently related. Conclusions,Violent recidivism was so unusual that, on this outcome, it could take many years to show any effect of the new service. Desistance from substance use, compliance with treatment and maintenance of stable housing may be better indicators of success, and their achievement a good preventive strategy. Copyright © 2007 John Wiley & Sons, Ltd. [source] AN INTRODUCTION TO THE CLIMBING DICENTRAS , THE GENUS DACTYLICAPNOS IN CULTIVATIONCURTIS'S BOTANICAL MAGAZINE, Issue 3 2008Nicholas Hind Summary The genus Dactylicapnos Wall. (Papaveraceae: Fumarioideae: Corydaleae) consists of annual and perennial climbers with half-hardy stems, tendrils on the leaves and, in most species, perennating, tuberous rootstocks. A short history of the genus is given here and its status is discussed. At present four species appear to be in cultivation and cultivation notes for these are provided. A description of the genus is given together with a synopsis, or nomenclator, of the species and associated names. [source] Migratory connectivity in a declining bird species: using feather isotopes to inform demographic modellingDIVERSITY AND DISTRIBUTIONS, Issue 4 2010Thomas S. Reichlin Abstract Aim, Conservation programmes for endangered migratory species or populations require locating and evaluating breeding, stopover and wintering areas. We used multiple stable isotopes in two endangered European populations of wrynecks, Jynx torquilla L., to locate wintering regions and assess the degree of migratory connectivity between breeding and wintering populations. Location, Switzerland and Germany. Methods, We analysed stable nitrogen (,15N), carbon (,13C) and hydrogen (,D) isotopes from wing feathers from two populations of wrynecks to infer their wintering origins and to assess the strength of migratory connectivity. We tested whether variation in feather isotopic values within the Swiss population was affected by bird age and collection year and then considered differences in isotopic values between the two breeding populations. We used isotopic values of summer- and winter-grown feathers to estimate seasonal distributions. Finally, we calculated a species-specific ,D discrimination factor between feathers and mean annual ,D values to assign winter-grown feathers to origin. Results, Bird age and collection year caused substantial isotopic variation in winter-grown feathers, which may be because of annually variable weather conditions, movements of birds among wintering sites and/or reflect asynchronous moulting or selection pressure. The large isotopic variance in winter-grown feathers nevertheless suggested low migratory connectivity for each breeding population, with partially overlapping wintering regions for the two populations. Main conclusions, Isotopic variance in winter-grown feathers of two breeding populations of wrynecks and their geographical assignment point to defined, albeit overlapping, wintering areas, suggesting both leapfrog migration and low migratory connectivity. On this basis, integrative demographic models can be built looking at seasonal survival patterns with links to local environmental conditions on both breeding and wintering grounds, which may elucidate causes of declines in migratory bird species. [source] Climate-driven decrease in erosion in extant Mediterranean badlandsEARTH SURFACE PROCESSES AND LANDFORMS, Issue 11 2010Michèle L. Clarke Abstract Badland areas provide some of the highest erosion rates globally. Most studies of erosion have insufficient lengths of record to interrogate the impacts of decadal-scale changes in precipitation on rates of badland erosion in regions such as the Mediterranean, which are known to be sensitive to land degradation and desertification. Erosion measurements, derived from field monitoring using erosion pins, in southern Italy during the period 1974,2004 are used to explore the impacts of changing precipitation patterns on badland erosion. Erosion on badland inter-rill areas is strongly correlated with cumulative rainfall over each monitoring period. Annual precipitation has a substantial dynamic range, but both annual and winter (December, January, February) rainfall amounts in southern Italy show a steady decrease over the period 1970,2000. The persistence of positive values of the winter North Atlantic Oscillation index in the period 1980,2000 is correlated with a reduction in the winter rainfall amounts. Future climate scenarios show a reduction in annual rainfall across the western and central Mediterranean which is likely to result in a further reduction in erosion rates in existing badlands. Copyright © 2010 John Wiley & Sons, Ltd. [source] Climatic influence on the inter-annual variability of late-Holocene minerogenic sediment supply in a boreal forest catchmentEARTH SURFACE PROCESSES AND LANDFORMS, Issue 4 2010Gunilla Petterson Abstract Processes controlling sediment yield vary over a range of timescales, although most process-based observations are extremely short. Lake sediments, however, can be used to extend the observational timescale and are particularly useful when annually laminated (varved) sediment is present. The sediment record at Kassjön (N. Sweden) consists of ,6400 varves, each 0·5,1 mm thick. Image analysis was used to determine grey-scale variation and varve thickness from which annual minerogenic accumulation rate (MinAR) (mg cm,2 year,1) was inferred for the period 4486 BC , AD 1900. MinAR varies on annual to centennial scales and mainly reflects channel bank erosion by the inflow streams. The mineral input reflects the intensity of the spring run-off, which is dependent on the amount of snow accumulated during the winter, and hence MinAR is a long-term record of variability in past winter climate; other factors will be a variable response to catchment uplift, vegetation succession and pedogenesis. A major shift from low to high MinAR occurred ,250 BC, and peaks occurred around AD 250, 600, 1000, 1350 and 1650. Wavelet power spectrum analysis (confirmed by Fourier analyses) indicated significantly different periodicities throughout the period 4000 BC , AD 1700, including 275 years for the period 4000 BC , 2900 BC, 567 years for the period 2901 BC , 1201 BC, and 350 and 725 years for the period 1200 BC , AD 1700. The long-term, centennial scale variability (,350 years) may reflect solar forcing (cf the 385-year peak in tree-ring calibrated 14C activity) but interestingly, there is no obvious link to high frequency forcing, such as the North Atlantic Oscillation. The high resolution component of the record highlights the relevance of varved lake sediment records for understanding erosion dynamics in undisturbed forested catchments and their link to long-term climate dynamics and future climate change. Copyright © 2010 John Wiley & Sons, Ltd. [source] Interpolation processes using multivariate geostatistics for mapping of climatological precipitation mean in the Sannio Mountains (southern Italy)EARTH SURFACE PROCESSES AND LANDFORMS, Issue 3 2005Nazzareno Diodato Abstract The spatial variability of precipitation has often been a topic of research, since accurate modelling of precipitation is a crucial condition for obtaining reliable results in hydrology and geomorphology. In mountainous areas, the sparsity of the measurement networks makes an accurate and reliable spatialization of rainfall amounts at the local scale difficult. The purpose of this paper is to show how the use of a digital elevation model can improve interpolation processes at the subregional scale for mapping the mean annual and monthly precipitation from rainfall observations (40 years) recorded in a region of 1400 km2 in southern Italy. Besides linear regression of precipitation against elevation, two methods of interpolation are applied: inverse squared distance and ordinary cokriging. Cross-validation indicates that the inverse distance interpolation, which ignores the information on elevation, yields the largest prediction errors. Smaller prediction errors are produced by linear regression and ordinary cokriging. However, the results seem to favour the multivariate geostatistical method including auxiliary information (related to elevation). We conclude that ordinary cokriging is a very flexible and robust interpolation method because it can take into account several properties of the landscape; it should therefore be applicable in other mountainous regions, especially where precipitation is an important geomorphological factor. Copyright © 2005 John Wiley & Sons, Ltd. [source] Error estimation of closed-form solution for annual rate of structural collapseEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 15 2008Brendon A. Bradley Abstract With the increasing emphasis of performance-based earthquake engineering in the engineering community, several investigations have been presented outlining simplified approaches suitable for performance-based seismic design (PBSD). Central to most of these PBSD approaches is the use of closed-form analytical solutions to the probabilistic integral equations representing the rate of exceedance of key performance measures. Situations where such closed-form solutions are not appropriate primarily relate to the problem of extrapolation outside of the region in which parameters of the closed-form solution are fit. This study presents a critical review of the closed-form solution for the annual rate of structural collapse. The closed-form solution requires the assumptions of lognormality of the collapse fragility and power model form of the ground motion hazard, of which the latter is more significant regarding the error of the closed-form solution. Via a parametric study, the key variables contributing to the error between the closed-form solution and solution via numerical integration are illustrated. As these key variables cannot be easily measured, it casts doubt on the use of such closed-form solutions in future PBSD, especially considering the simple and efficient nature of using direct numerical integration to obtain the solution. Copyright © 2008 John Wiley & Sons, Ltd. [source] Energy input and zooplankton species richnessECOGRAPHY, Issue 6 2007Dag O. Hessen What are the relative contribution of temperature and solar irradiance as types of energy deliveries for species richness at the ecosystem level? In order to reveal this question in lake ecosystems, we assessed zooplankton species richness in 1891 Norwegian lakes covering a wide range in latitude, altitude, and lake area. Geographical variables could largely be replaced by temperature-related variables, e.g. annual monthly maximum temperature or growth season. Multivariate analysis (PCA) revealed that not only maximum monthly temperature, but also energy input in terms of solar radiation were closely associated with species richness. This was confirmed by stepwise, linear regression analysis in which lake area was also found to be significant. We tested the predictive power of the "metabolic scaling laws" for species richness by regressing Ln of species richness over the inverse of the air temperature (in Kelvin), corrected for the activation energy (eV) as predicted by the Boltzmann constant. A significant, negative slope of 0.78 for ln richness over temperature, given as 1/kT, was found, thus slightly higher than the range of slopes predicted from the scaling law (0.60,0.70). Temperature basically constrained the upper bound of species number, but it was only a modest predictor of actual richness. Both PCA-analysis and linear regression models left a large unexplained variance probably due to lake-specific properties such as catchment influence, lake productivity, food-web structure, immigration constraints or more stochastic effects. [source] A test of the relationship between seasonal rainfall and saguaro cacti branching patternsECOGRAPHY, Issue 4 2003Taly Dawn Drezner Reproductive output, as well as photosynthetically active radiation interception and CO2 uptake, increase as saguaro cacti Carnegiea gigantea (Engelm.) Britt. and Rose branch, and branching increases with increasing moisture. The Sonoran Desert experiences distinct summer and winter precipitation regimes that vary in both geography and scale. Many aspects of saguaro ecology are known to depend on the summer rains, which has resulted in an emphasis on summer rains in the literature. Similarly, branching studies have been limited geographically to areas that receive relatively high amounts of summer rainfall. These studies, therefore, attribute branching patterns to the summer (or possibly annual) rains, and conclusions reflect the summer precipitation bias. Environmental variability in space was explored in the present study to investigate saguaro branching patterns. I collected height and branching data in thirty saguaro populations across their American range. Stepwise regression was used to determine which climate, vegetation and soil variables best predict branching. Contrary to the literature, this study found that winter precipitation, particularly from January to April, was the best predictor of branching, not summer or annual rain. Surprisingly, the relationship between the summer monsoons (July and August precipitation) and branching was negative. This is likely due to the fact that summer and winter rainfall patterns are geographically distinct. Winter precipitation appears to play a key role in branching, and thus in seed production. This suggests that saguaros benefit from moisture during the winter, possibly utilizing cold-season rains for increasing their reproductive output through branching, and challenging the view that the summer rains dominate virtually every aspect of the saguaro life-cycle, and creating a more balanced view of saguaro ecology. [source] Short and long term consequences of increases in exotic species richness on water filtration by marine invertebratesECOLOGY LETTERS, Issue 8 2009Jarrett Byrnes Abstract Although recent research has considered the consequences of global declines in the number of species, less attention has focused on the aggregate effects of regional increases in species richness as a result of human-mediated introductions. Here we examine several potential ecosystem consequences of increasing exotic species diversity of suspension feeding marine invertebrates. First, we experimentally manipulated native and non-native suspension feeder richness and measured its effect on short-term phytoplankton clearance rates. Multispecies communities all performed similarly, regardless of whether they were dominated by natives, exotics, or an even mix of the two. Individual species varied considerably in filtration rates, but non-native species often filtered less than the most similar native. Second, we determined potential changes in integrated function over time by comparing seasonal patterns of recruitment as a proxy for the ability to quickly recover filtration capacity after a disturbance. We found that exotic species have complementary seasonal phenologies both to native species and each other. Our results suggest that the consequences of local increases in species richness due to invasions may be manifest over long (annual to interannual) time scales, even when short term changes in ecosystem function are negligible. [source] Elevated CO2 and herbivory influence trait integration in Arabidopsis thalianaECOLOGY LETTERS, Issue 9 2004M. Gabriela Bidart-Bouzat Abstract We lack information on how elevated CO2, and its interaction with other factors like herbivory, affect levels and patterns of trait integration in plants. We experimentally tested the hypothesis that elevated CO2 disrupts and restructures functional associations among plant traits, in the selfing annual, Arabidopsis thaliana. We tested for these effects both in the presence and absence of herbivory by larvae of the diamondback moth, Plutella xylostella. Elevated CO2, both alone and combined with moth herbivory, modified integrated trait responses. In addition, integration under different environments was genotype-specific. These results imply that global changes in CO2 are likely to cause divergent evolutionary outcomes among populations of plants that differ in the initial structure of their quantitative genetic variation. [source] The importance of drinking frequency in evaluating individuals' drinking patterns: implications for the development of national drinking guidelinesADDICTION, Issue 7 2009Catherine Paradis ABSTRACT Aims This paper examines the relationship between frequency of drinking, usual daily consumption and frequency of binge drinking, taking into consideration possible age and gender differences. Participants and design Subjects were 10 466 current drinkers (5743 women and 4723 men) aged between 18 and 76 years, who participated in the GENACIS Canada (GENder Alcohol and Culture: an International Study) study. Setting Canada. Measurements The independent variable was the annual drinking frequency. The dependent variables were the usual daily quantity consumed, annual, monthly and weekly frequency of binge drinking (five drinks or more on one occasion). Findings Logistic regressions show (i) that those who drink less than once a week are less likely than weekly drinkers to take more than two drinks when they do drink; (ii) that the usual daily quantity consumed by weekly drinkers is not related to their frequency of drinking; but that (iii) the risk and frequency of binge drinking increase with the frequency of drinking. Conclusions Given that risk and frequency of binge drinking among Canadians increases with their frequency of drinking, any public recommendation to drink moderately should be made with great caution. [source] Space,time modeling of 20 years of daily air temperature in the Chicago metropolitan regionENVIRONMETRICS, Issue 5 2009Hae-Kyung Im Abstract We analyze 20 years of daily minimum and maximum air temperature data in the Chicago metropolitan region and propose a parsimonious model that describes their mean function and the space,time covariance structure. The mean function contains a long-term trend, annual and semiannual harmonics, and physical covariates such as latitude, distance to the Lake Michigan, and winds, each interacted with the harmonic terms, thus allowing the effects of physical covariates to vary smoothly over time. The temporal correlation at a given location is described using an ARMA(1,2) model. The residuals (innovations) from this models are treated as independent replications of a spatial process with covariance structure in the Matérn class. The space,time covariance structure parameters are allowed to vary seasonally. Using the estimated covariance structure, we interpolate the temperature to a fine grid in the Chicago metropolitan region. This procedure borrows information from temporally and spatially adjacent data. The methods presented in this paper should be useful to approach other environmental problems where the data are discrete and regular in time but irregular in space. Copyright © 2008 John Wiley & Sons, Ltd. [source] Nonparametric prediction intervals for the future rainfall records,ENVIRONMETRICS, Issue 5 2006Mohammad Z. Raqab Abstract Prediction of records plays an important role in the environmental applications, especially, prediction of rainfall extremes, highest water levels, sea surface, and air record temperatures. In this paper, based on the observed records drawn from a sequence sample of independent and identically random variables, we develop prediction intervals as well as prediction upper and lower bounds for records from another independent sequence. We extend the prediction problem to include prediction regions for joint upper records from a future sequence sample. The Bonferouni's inequality is used to choose appropriate prediction coefficients for the joint prediction. A real data set representing the records of the annual (January 1,December 31) rainfall at Los Angeles Civic Center is addressed to illustrate the proposed prediction procedures in the environmental applications. Copyright © 2005 John Wiley & Sons, Ltd. [source] Temporal and shrub adaptation effect on soil microbial functional diversity in a desert systemEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 6 2009V. Saul-Tcherkas Summary The Negev Desert is characterized by spatial and temporal patterns of resource distribution, in which soil biota are considered to be among the most sensitive biological characteristics, easily influenced by changes related to soil and abiotic factors. Soil water availability and organic matter are among the most important factors, acting as triggers that determine the length of the period of activity. The main source of organic matter in this xeric environment is input from annual and perennial shrubs. In order to persist and propagate in this xeric environment, the plants have developed different ecophysiological adaptations (e.g. the excretion of salt (Reaumuria negevensis) and chemical compounds (Artemisia sieberi) via the leaves). We found that the values of soil moisture obtained for soil samples collected in the vicinity of R. negevensis were larger than for samples collected in the vicinity of Noaea mucronata and A. sieberi and in the open area. The maximum values of CO2 evolution, microbial biomass and Shannon index (H,) were obtained for the samples collected from the vicinity of N. mucronata. Therefore, we assume that the vicinity of N. mucronata afforded the best conditions for the soil bacterial community. In the Negev Desert, we also found that water availability and pulses of rain compared with frequent rainfall influenced CO2 evolution, microbial biomass, qCO2 and the Shannon index (H,). The differences in water amount and availability between the two rainy seasons caused larger values in most of the properties during the first four seasons (December 2005,November 2006) compared with the last four seasons (December 2006,November 2007) for most of the samples. [source] PROMISCUITY DRIVES SEXUAL SELECTION IN A SOCIALLY MONOGAMOUS BIRDEVOLUTION, Issue 9 2007Michael S. Webster Many socially monogamous species paradoxically show signs of strong sexual selection, suggesting cryptic sources of sexual competition among males. Darwin argued that sexual selection could operate in monogamous systems if breeding sex ratios are biased or if some males attract highly fecund females. Alternatively, sexual selection might result from promiscuous copulations outside the pair bond, although several recent studies have cast doubt on this possibility, in particular by showing that variance in apparent male reproductive success (number of social young) differs little from variance in actual male reproductive success (number of young sired). Our results from a long-term study of the socially monogamous splendid fairy-wren (Malurus splendens) demonstrate that such comparisons are misleading and do not adequately assess the effects of extra-pair paternity (EPP). By partitioning the opportunity for selection and calculating Bateman gradients, we show that EPP has a strong effect on male annual and lifetime fitness, whereas other proposed mechanisms of sexual selection do not. Thus, EPP drives sexual selection in this, and possibly other, socially monogamous species. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||