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Selected AbstractsSurvival rates for a declining population of bottlenose dolphins in Doubtful Sound, New Zealand: an information theoretic approach to assessing the role of human impactsAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 6 2009Rohan J. C. Currey Abstract 1.The bottlenose dolphins of Doubtful Sound, New Zealand are a declining population at the southern limit of the species' range, exposed to impacts from tourism and habitat modification. Patterns in apparent annual survival were analysed from photographic resightings of naturally marked adults (1990 to 2008) and calves within the first year of life (1994 to 2008) using capture-recapture models. 2.The most parsimonious model for adults provided a time-invariant, sex-invariant estimate of survival (,a(1990,2008)=0.9374; 95% CI: 0.9170,0.9530), marginally lower than prior estimates for wild bottlenose dolphins. 3.The most parsimonious model for calves indicated a significant time-variant decline in survival from an estimate similar to other populations (,c(1994,2001)=0.8621; 95% CI: 0.6851,0.9473) to a current estimate that is, to our knowledge, the lowest recorded for free-ranging bottlenose dolphins (,c(2002,2008)=0.3750; 95% CI: 0.2080,0.5782). 4.Information theoretic evidence ratios suggested that observed patterns in calf survival were 22 times more likely to be explained by a decline coincident with the opening of a second tailrace tunnel for a hydroelectric power station than by a decline in any other year or across multiple years. 5.Projections using an age-structured stochastic population model indicated that the current level of calf survival was unsustainable (population decline: 100% of model runs; population extinction: 41.5% of model runs) and was a key factor in the observed population decline in Doubtful Sound. Copyright © 2008 John Wiley & Sons, Ltd. [source] Prediction studies supported by computer on potato late blight in central Anatolia in Turkey,EPPO BULLETIN, Issue 2 2007E. Cakir Prediction of potato late blight epidemics, caused by Phytophthora infestans (Mont) de Bary, was studied in three different villages of Bolu Province having large potato growing areas with the Winstel and Ullrich Schrodter models in the years 2002,05. During these years, a late blight outbreak was observed only in 2005 with the disease being less apparent in the other years. The Ullrich Schrodter model was found to poorly predict potato late blight epidemics in 2005. The Winstel model gave first warnings too early but correctly predicted late infections. Both the A1 and A2 mating types were found in Central Anatolia for the first time, in Bolu province. [source] The sensitivity of annual grassland carbon cycling to the quantity and timing of rainfallGLOBAL CHANGE BIOLOGY, Issue 6 2008WENDY W. CHOU Abstract Global climate models predict significant changes to the rainfall regimes of the grassland biome, where C cycling is particularly sensitive to the amount and timing of precipitation. We explored the effects of both natural interannual rainfall variability and experimental rainfall additions on net C storage and loss in annual grasslands. Soil respiration and net primary productivity (NPP) were measured in treatment and control plots over four growing seasons (water years, or WYs) that varied in wet-season length and the quantity of rainfall. In treatment plots, we increased total rainfall by 50% above ambient levels and simulated one early- and one late-season storm. The early- and late-season rain events significantly increased soil respiration for 2,4 weeks after wetting, while augmentation of wet-season rainfall had no significant effect. Interannual variability in precipitation had large and significant effects on C cycling. We observed a significant positive relationship between annual rainfall and aboveground NPP across the study (P=0.01, r2=0.69). Changes in the seasonal timing of rainfall significantly affected soil respiration. Abundant rainfall late in the wet season in WY 2004, a year with average total rainfall, led to greater net ecosystem C losses due to a ,50% increase in soil respiration relative to other years. Our results suggest that C cycling in annual grasslands will be less sensitive to changes in rainfall quantity and more affected by altered seasonal timing of rainfall, with a longer or later wet season resulting in significant C losses from annual grasslands. [source] Wavelet analysis of inter-annual variability in the runoff regimes of glacial and nival stream catchments, Bow Lake, AlbertaHYDROLOGICAL PROCESSES, Issue 6 2003Melissa Lafreničre Abstract Continuous wavelet analyses of hourly time series of air temperature, stream discharge, and precipitation are used to compare the seasonal and inter-annual variability in hydrological regimes of the two principal streams feeding Bow Lake, Banff National Park, Alberta: the glacial stream draining the Wapta Icefields, and the snowmelt-fed Bow River. The goal is to understand how water sources and flow routing differ between the two catchments. Wavelet spectra and cross-wavelet spectra were determined for air temperature and discharge from the two streams for summers (June,September) 1997,2000, and for rainfall and discharge for the summers of 1999 and 2000. The diurnal signal of the glacial runoff was orders of magnitude higher in 1998 than in other years, indicating that significant ice exposure and the development of channelized glacial drainage occurred as a result of the 1997,98 El Nińo conditions. Early retreat of the snowpack in 1997 and 1998 led to a significant summer-long input of melt runoff from a small area of ice cover in the Bow River catchment; but such inputs were not apparent in 1999 and 2000, when snow cover was more extensive. Rainfall had a stronger influence on runoff and followed quicker flow paths in the Bow River catchment than in the glacial catchment. Snowpack thickness and catchment size were the primary controls on the phase relationship between temperature and discharge at diurnal time scales. Wavelet analysis is a fast and effective means to characterize runoff, temperature, and precipitation regimes and their interrelationships and inter-annual variability. The technique is effective at identifying inter-annual and seasonal changes in the relative contributions of different water sources to runoff, and changes in the time required for routing of diurnal meltwater pulses through a catchment. However, it is less effective at identifying changes/differences in the type of the flow routing (e.g. overland flow versus through flow) between or within catchments. Copyright © 2003 John Wiley & Sons, Ltd. [source] Double-nesting behaviour and sexual differences in breeding success in wild Red-legged Partridges Alectoris rufaIBIS, Issue 4 2009FABIÁN CASAS Double-nesting behaviour, a rare breeding system in which females lay in two nests, one incubated by herself and the other one by her mate, could be considered an intermediate stage in the evolutionary trend from biparental to uniparental care of single clutches. We examined the occurrence and success of double-nesting behaviour in Red-legged Partridges Alectoris rufa in Central Spain. Clutch size and hatching success were recorded, as well as the variation in these between years and between incubating sexes. Participation in incubation was higher for females (94.76%) than males (41.0%), and the proportion of incubating males varied markedly between years, with no incubating males in one dry year and approximately 50% of males incubating in other years. There was significant variation among years and between sexes in laying date, clutch size and hatching success. Clutch size decreased with later laying date in males and females. The probability of clutch loss to predation differed between sexes, being much higher for nests incubated by females. Our results suggest that both rainfall and predation influence the occurrence and success of double-nesting. [source] Chick provisioning rates and growth in Blacklbrowed Albatross Diomedea melanophris and Grey-headed Albatross D. chrysostoma at Bird Island, South GeorgiaIBIS, Issue 4 2000NICOLAS HUIN We compared the parental division of labour and the pattern and rate of parental provisioning by two sympatric species of albatross of similar mass and breeding timetable but differing in diet and in the duration of chick-rearing. Using electronic weighing platforms inside artificial nests, we recorded chick mass of Black-browed Albatross and Grey-headed Albatross at Bird Island, South Georgia every 10 minutes for both species in 1993 and 1994 and for each species in two other years between 1990 and 1996. The chick mass data (nearly one million weighings) were used to calculate meal mass (over 5000 meals) and intervals between meals. Adult birds were fitted with radio-transmitters which allowed each meal to be allocated to the appropriate parent. The combination of meal mass and foraging trip duration were used to calculate provisioning rates for chicks and individual adults. Overall, Black-browed Albatrosses delivered significantly lighter meals (569 g) than Grey-headed Albatrosses (616 g) but more frequently (every 2.07 days and 2.50 days respectively). Thus combining foraging trip data for both parents, Black-browed Albatross chicks received a meal every 1.22 days compared with 1.26 days for Greyheaded Albatross. These rates did not differ significantly. The contribution of each sex of each species in chick provisioning fluctuated between years, being similar in some years or biased towards males in others. Chicks of both species that failed to fledge received smaller, less frequent meals than successful chicks. In 1990 and 1994, Black-browed Albatross chick provisioning rates were lower than in 1992 and 1993. In 1990, both meal mass and trip duration were affected, but only in 1994 was trip duration longer. Greyheaded Albatross chick provisioning rate was lower in 1994 than in other years but trip duration was longer. In each species, significant changes in meal mass and trip duration occurred within the chick-rearing period. Chick provisioning rates invariably declined before chicks attained their peak mass. For both species, chick growth rates and peak and fledging mass, but not fledging age, were affected by differences in provisioning rate. [source] Europe's 2003 heat wave: a satellite view of impacts and land,atmosphere feedbacksINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 6 2006Benjamin F. Zaitchik Abstract A combination of satellite imagery, meteorological station data, and the NCEP/NCAR reanalysis has been used to explore the spatial and temporal evolution of the 2003 heat wave in France, with focus on understanding the impacts and feedbacks at the land surface. Vegetation was severely affected across the study area, especially in a swath across central France that corresponds to the Western European Broadleaf (WEB) Forests ecological zone. The remotely sensed surface temperature anomaly was also greatest in this zone, peaking at +15.4 °C in August. On a finer spatial scale, both the vegetation and surface temperature anomalies were greater for crops and pastures than for forested lands. The heat wave was also associated with an anomalous surface forcing of air temperature. Relative to other years in record, satellite-derived estimates of surface-sensible heat flux indicate an enhancement of 48,61% (24.0,30.5 W m,2) in WEB during the August heat wave maximum. Longwave radiative heating of the planetary boundary layer (PBL) was enhanced by 10.5 W m,2 in WEB for the same period. The magnitude and spatial structure of this local heating is consistent with models of the late twenty-first century climate in France, which predict a transitional climate zone that will become increasingly affected by summertime drought. Models of future climate also suggest that a soil-moisture feedback on the surface energy balance might exacerbate summertime drought, and these proposed feedback mechanisms were tested using satellite-derived heat budgets. Copyright © 2006 Royal Meteorological Society. [source] A revisit on older adults suicides and Severe Acute Respiratory Syndrome (SARS) epidemic in Hong KongINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 12 2008Y. T. Cheung Abstract Background The Severe Acute Respiratory Syndrome (SARS) outbreak in 2003 had an enormous impact on Hong Kong society and the suicide rate was also at its historical high, 18.6 per 100,000. The most significant increase was found among the older adults aged 65 or above. Methods Poisson Regression Models were used to examine impact of the SARS epidemic on older adults suicides in Hong Kong. A complete set of the suicide statistics for the period 1993,2004 from the Coroners' Court were made available for the analysis. Chi-square test was used to compare the profile of the older adult suicide cases in the pre-SARS, peri-SARS and post-SARS periods. Results It showed an excess of older adults suicides in April 2003, when compared to the month of April of the other years. A trough, instead of the usual summer peak, was observed in June, suggesting some of the older adults suicides might have been brought forward. On a year basis, the annual older adult's suicide rates in 2003 and 2004 were significantly higher than that in 2002, suggesting the suicide rate did not return to the level before the SARS epidemic. Based on the Coroners' suicide death records, overall severity of illness, level of dependency and worrying of having sickness among the older adult suicides were found to be significantly different in the pre-SARS, peri-SARS and post-SARS periods. Conclusion The SARS epidemic was associated with an increase in older adults' suicide rate in April 2003 and some suicide deaths in June 2003 might have been brought forward. Moreover, an increase in the annual older adults' suicide rate in 2003 was observed and the rate in 2004 did not return to the level of 2002. Loneliness and disconnectedness among the older adults in the community were likely to be associated with the excess older adults' suicides in 2003. Maintaining and enhancing mental well being of the public over the period of epidemic is as important as curbing the spread of the epidemic. Attention and effort should also be made to enhance the community's ability to manage fear and anxiety, especially in vulnerable groups over the period of epidemic to prevent tragic and unnecessary suicide deaths. Copyright © 2008 John Wiley & Sons, Ltd. [source] Developing a valid and reliable self-efficacy in clinical performance scaleINTERNATIONAL NURSING REVIEW, Issue 2 2009F. Cheraghi phd Aim:, This paper describes the development and testing of the Self-Efficacy in Clinical Performance (SECP) instrument for nursing students. Background:, Accurate measurement of self-efficacy can be used to predict nursing students' clinical performance. The literature review indicated there is no existing self-efficacy in clinical performance instrument for Iranian nursing students. Methods:, To clarify the concept of self-efficacy in clinical performance, 28 semi-structured interviews and three focus groups were conducted. A self-efficacy framework with well-developed theoretical constructs was formed. A review of literature and content analysis of the interview transcripts identified subscales and items to be included in the instrument. Then, a methodological design was used. The SECP was developed into 69 Likert-format items, which were evaluated by 20 nursing experts in the form of content validity index. The scale's validity and reliability were tested in a randomized sample of 207 final year nursing students. Findings:, The final scale consists of four dimensions with 37 items. The overall scale internal reliability had , = 0.96; the dimensions Cronbach's , ranged from 0.90 to 0.92. Test,retest reliability with a 2-week time interval was: r = 0.94. In addition, concurrent validity was obtained (r = 0.73, P = 0.01). Conclusions:, The SECP has demonstrated evidence of content validity, construct validity, concurrent validity, internal consistency reliability and stability. Statistical analysis provided an objective tool for assessing nursing students' self-efficacy in clinical performance. It may have been fruitful to further test the instrument with students from other years of their education. [source] On fumonisin incidence in monoculture maize under no-till, conventional tillage and two nitrogen fertilisation levelsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 7 2008Adriano Marocco Abstract BACKGROUND:Fusarium ear rot and fumonisin contamination are serious problems for maize growers. The lack of maize genotypes highly resistant to fumonisin contamination emphasises the need for management strategies to prevent contamination by this mycotoxin. There are conflicting reports regarding no-till and nitrogen (N) fertilisation practices in relation to the incidence of fumonisins. In this study the effect of no-till compared with conventional tillage and of N fertilisation rates on fumonisin occurrence was investigated over three years in Northern Italy. RESULTS: The average contamination of grain by fumonisins B1 and B2 over the three years was significantly different, with a lower value in 2000 (516 µg kg,1) than in the other years (5846 and 3269 µg kg,1 in 2001 and 2002 respectively). Conventional tillage and no-till treatments had no significant effect on the incidence of fumonisins. This finding suggests that above-ground residues infected by Fusarium would not lead to an increase in fumonisin incidence. However, N fertilisation significantly increased fumonisin levels, by 99 and 70% in 2000 and 2001 respectively. CONCLUSION: Maize monoculture does not show a cumulative effect on the occurrence of fumonisins, while high rates of N fertiliser consistently result in elevated fumonisin levels. Both these effects can be influenced by annual meteorological fluctuations. Copyright © 2008 Society of Chemical Industry [source] Tolerance of barley seed germination to cold- and drought-stress expressed as seed vigourPLANT BREEDING, Issue 3 2003O. Chloupek Abstract In barley, high seed vigour is a precondition for rapid and homogenous field emergence and good malting quality. Seed vigour was defined as germination percentage under stress conditions (10°C, drought stress - 2 Bars) in 7-8 barley varieties grown in 7-8 locations in the Czech Republic over 7 years. Three of the 7 years were not suitable for high seed quality, probably because of unsuitable weather, as average seed vigour reached only 61, 77 and 86%, respectively. In the remaining 4 years, the average vigour exceeded 94%. The impact of variety on seed vigour was higher in the ,bad years' and the impact of location was higher in the other years. Varieties with higher vigour from all locations in the ,bad years' were identified. Lower vigour was related to the high occurrence of fungi (indicated by ergosterol assays) and to lower field emergence rates of seed samples. The results support the possibility of selecting for improvement of barley seed vigour, which is related to tolerance to various conditions during emergence and to homogenous malting. [source] Effects of diseases on the growth and yield of spring linseed (Linum usitatissimum), 1988,1998ANNALS OF APPLIED BIOLOGY, Issue 3 2000S A M PERRYMAN Summary In spring linseed field experiments with fungicides at Rothamsted from 1988 to 1998, substantial yield losses assoeiated with diseases occurred in three years and slight losses could be associated with diseases in other years. These yield losses were related to decreases in yield components (thousand grain weights and number of capsules). Leaf browning was observed each year and percentage leaf area with browning was the disease factor most consistently related to yield losses (in five years). Yield loss relationships for these five years suggested that for each 10% increase in percentage leaf area with browning there was a yield loss of 0.10 to 0.18 t ha,1. Stem browning, lesions on capsules and powdery mildew were associated with yield losses in two years, three years and one year, respectively. Yield losses were greatest in years when the period of flowering and early capsule development in June and July was wetter than average; the predominant disease was grey mould (Botrytis cinerea) in wet years up to 1996, whereas pasmo (Mycosphaerella linicola) was most important in 1997 and 1998. Observed yield losses were small in hot, dry years when powdery mildew (Sphaerotheca lini) and verticillium (Verticillium dahliae) were the predominant diseases. [source] Multiyear ground-based and satellite observations of aerosol properties over a tropical urban area in IndiaATMOSPHERIC SCIENCE LETTERS, Issue 1 2007K. V. S. Badarinath Abstract Aerosol particle size distributions along with their spatial and temporal variability are important for describing both direct and indirect radiative forcing. In this study, the variation of black carbon (BC) aerosols, total aerosol mass loading and aerosol optical depth (AOD) over an urban region of Hyderabad, south India, was analyzed for 3 consecutive years from 2003 to 2005. The AOD was measured using a handheld multichannel sun-photometer at six wavelengths centered on 380, 440, 500, 675, 870 and 1020 nm and aerosol mass,size distribution was made using a quartz crystal microbalance (QCM) cascade impactor. In addition, satellite remote-sensing data from nighttime DMSP-OLS images were analyzed for inferring ancillary sources of aerosols. Results from temporal analysis (2004,2006) suggest that aerosol mass loading and BC mass concentration increased considerably over the 3-year time-period mainly due to increasing vehicular traffic from urban population growth. DMSP-OLS nighttime images for different years suggested higher forest fire occurrences in the year 2004 compared to other years. The annual mean AOD at 550 nm from moderate resolution imaging spectroradiometer (MODIS) showed relatively high values during 2004. Copyright © 2007 Royal Meteorological Society [source] Changes in body condition and body size affect breeding and recruitment in fluctuating house mouse populations in south-eastern AustraliaAUSTRAL ECOLOGY, Issue 3 2009GREGORY J. MUTZE Abstract Changes in body condition and body size in field populations of house mice, Mus domesticus, were examined to investigate why mouse populations do not increase rapidly in some years when favourable environmental and demographic conditions indicate they might. Mice had repeated seasonal patterns each year in breeding, growth rates and body condition that reflected the seasonal availability of food, but mean levels for each parameter varied among years. In most years mice lost body condition during summer, breeding declined and population growth slowed. Rapid population growth occurred when body condition was generally high and was maintained throughout summer. Female mice with large body length were more likely to breed than smaller mice, at all times, but changes in body condition accounted for most of the variability in female breeding activity between years and between habitats, and for the seasonal changes in the importance of body length. During rapid population growth, the recruitment rate of juveniles relative to the number of breeding females was 150,300% higher than in other years but adult survival rates were not higher. The data indicate that the ability of mice to maintain body condition, particularly when subject to moisture stress in summer, affects the proportion of females breeding, the number of juveniles weaned and their body condition at weaning, and is promoted by foraging conditions that favour maintenance of juvenile body condition after weaning. These factors, in turn, greatly affect juvenile recruitment rates and eventual population density of mice. Low juvenile survival is suggested as a reason that numbers of house mice in southern Australian cereal-growing areas do not increase rapidly in some years when other parameters are favourable. Similar processes are likely to play a role in regulating other rodent populations. [source] Structure and Level of Remuneration Across the Top Executive TeamAUSTRALIAN ACCOUNTING REVIEW, Issue 3 2010Michaela Rankin This paper details the level and structure of executive remuneration across the executive team from 2006 to 2009. Results indicate that the level and structure of executive pay varies across the executive team. There is a clear delineation between the level and structure of all components of pay for the CEO and Executive 1, and for other executives. Employees of finance firms receive higher levels of pay and greater proportions of bonus than do employees in other sectors. Pay structure in 2009 is different from other years in the study, indicating that the economic downturn of 2008 and 2009 has led to differences in executive pay. [source] |