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Average Condition (average + condition)
Selected AbstractsComparative Cognitive Effects of Carbamazepine and Gabapentin in Healthy Senior AdultsEPILEPSIA, Issue 6 2001Roy Martin Summary: ,Purpose: This study compared the cognitive effects of carbamazepine (CBZ) and gabapentin (GBP) in healthy senior adults by using a randomized, double-blind crossover design. Methods: Thirty-four senior adults were randomized to receive one of the two drugs followed by a 5-week treatment period. A 4-week washout phase preceded initiation of the second drug. Antiepileptic drugs (AEDs) were titrated to target doses of either CBZ (800 mg/day) or GBP (2,400 mg/day). Primary outcome measures were standardized neuropsychological tests of attention/vigilance, psychomotor speed, motor speed, verbal and visual memory, and the Profile of Mood State (POMS), yielding a total of 17 variables. Each subject received cognitive testing at predrug baseline, end of first drug phase, end of second drug phase, and 4 weeks after completion of the second drug phase. Results: Fifteen senior adults (mean age, 66.5 years; range, 59,76 years) completed the study. Seniors completing the study did not differ significantly from noncompleting seniors in terms of demographic features or baseline cognitive performances. Fifteen of the 19 seniors not completing the study dropped out while receiving CBZ. Adverse events were frequently reported for both AEDs, although they were more common for CBZ. Mean serum levels for the completers were within midrange clinical doses (CBZ, 6.8 ,g/ml; GBP, 7.1 ,g/ml). Significant differences between CBZ and GBP were found for only one of 11 cognitive variables, with better attention/vigilance for GBP, although the effect was modest. Performances on the nondrug average were significantly better on 45% of cognitive variables compared with CBZ and 36% compared with GBP. The overall pattern of means favored GBP over CBZ on 15 of 17 (p < 0.001), nondrug over CBZ on 17 of 17 (p < 0.0000), and nondrug over GBP on eight of 17 (NS). Conclusions: Mild cognitive effects were found for both AEDs compared with the nondrug average condition. The magnitude of difference between the two AEDs across the cognitive variables was modest. Self-reported mood was not significantly affected by either AED. However, overall tolerability and side-effect profile of CBZ were poorer than those of GBP in senior adults at doses and titration rates reported in this study. [source] The carotenoid-based plumage coloration of adult Blue Tits Cyanistes caeruleus correlates with the health status of their broodIBIS, Issue 4 2006SERGIO HIDALGO-GARCIA The Blue Tit Cyanistes caeruleus is a passerine bird in which both sexes provide substantial care to the offspring and display conspicuous carotenoid-based plumage coloration. It has been shown that carotenoid-based coloration in birds reflects both individual quality and foraging ability. Because the body condition of nestlings usually depends on the capacity of their parents to feed them, I predicted that, independent of sex, those individuals with the most exaggerated carotenoid-based plumage coloration should raise offspring in better health. I found that although, in my study population, the smallest females were paired with the largest males, the brightest females were paired with the brightest and most intensely coloured males. I used body condition and T-cell-mediated immune response of nestlings as measures of their health status. Generalized mixed models showed that brighter and more-yellow adults reared offspring in better than average condition and immune response. Older males and smaller females were also able to raise offspring with better immune response. All these results suggest that the carotenoid-based plumage coloration of parents is somehow linked with individual quality, as it presents a significant and positive correlation with the health status of their growing chicks. Thus, the brightest and more intensely coloured individuals raised the healthiest offspring. [source] A reliability-based network design problemJOURNAL OF ADVANCED TRANSPORTATION, Issue 3 2005Piya Chootinan Abstract This paper presents a reliability-based network design problem. A network reliability concept is embedded into the continuous network design problem in which travelers' route choice behavior follows the stochastic user equilibrium assumption. A new capacity-reliability index is introduced to measure the probability that all of the network links are operated below their capacities when serving different traffic patterns deviating from the average condition. The reliability-based network design problem is formulated as a bi-level program in which the lower level sub-program is the probit-based stochastic user equilibrium problem and the upper level sub-program is the maximization of the new capacity reliability index. The lower level sub-program is solved by a variant of the method of successive averages using the exponential average to represent the learning process of network users on a daily basis that results in the daily variation of traffic-flow pattern, and Monte Carlo stochastic loading. The upper level sub-program is tackled by means of genetic algorithms. A numerical example is used to demonstrate the concept of the proposed framework. [source] Fluctuating asymmetry as a bio-indicator in isolated populations of the Taita thrush: a Bayesian perspectiveJOURNAL OF BIOGEOGRAPHY, Issue 5-6 2002Luc Lens Aim We examined whether developmental instability can be used as a bio-monitoring tool in the endangered Taita thrush (Turdus helleri L.) through the measurement of individual levels of fluctuating asymmetry in tarsus length. Because estimates of the association between developmental instability, stress and fitness derived from traditional regression are biased, we compared parameter estimates obtained from likelihood based analysis with those obtained from a Bayesian latent variable model. Location Taita thrushes were captured and measured in three isolated cloud forest fragments located in the Taita Hills of south-east Kenya. Methods We applied mixed-effects regression with Restricted Maximum Likelihood parameter estimation (performed with SAS version 8.0) and Bayesian latent variable modelling (performed with WINBUGS version 1.3 and CODA version 0.4) to estimate unbiased levels of developmental instability and to model relationships between developmental instability and body condition in 312 Taita thrushes. Results Likelihood and Bayesian analyses yielded highly comparable results. Individual levels of developmental instability were strongly inversely related to body condition in the subpopulation with the lowest average condition. In contrast, both variables were unrelated in two other subpopulations with higher average condition. Such heterogeneity in association was in the direction expected by developmental theory, given that higher condition suggests more benign ambient conditions. The estimated levels of body condition in the three subpopulations did not support their presumed ranking in relation to environmental stress. Developmental instability and body condition are therefore believed to reflect different aspects of individual fitness. Main conclusions Variation in developmental homeostasis, either modelled as observable variable (fluctuating asymmetry) or latent variable (developmental instability), appears a useful indicator of stress effects in the Taita thrush. Because relationships between environmental stress and developmental instability may depend on the extent to which stress-mediated changes in other components of phenotypic variation are correlated, the study of trait asymmetry should preferably be combined with that of other measures of trait variability, such as trait size or organismal condition. [source] Effect of abiotic factors on reproduction in the centre and periphery of breeding ranges: a comparative analysis in sympatric harriersECOGRAPHY, Issue 4 2001J. T. García Variables such as weather or other abiotic factors should have a higher influence on demographic rates in border areas than in central areas, given that climatic adaptation might be important in determining range borders. Similarly, for a given area, the relationship between weather and reproduction should be dissimilar for species which are in the centre of their breeding range and those that are near the edge. We tested this hypothesis on two sympatric ground-nesting raptors, the hen harrier Circus cyaneus and the Montagu's harrier Circus pygargus in Madrid, central Spain, where the hen harrier is at the southern edge of its breeding range in the western Palearctic and the Montagu's harrier is central in its distribution. We examined the reproductive success of both species during an 8-yr period, and looked at the influence of the most stressful abiotic factors in the study area (between-year variation in rainfall and within-year variation in temperature) on reproductive parameters. In the hen harrier, low levels of rainfall during the breeding season had a negative influence on annual fledging success and thus on population fledgling production. The relationship between rainfall and reproduction was probably mediated through food abundance, which in Mediterranean habitat depends directly on rainfall levels. In the Montagu's harrier, no negative effect of dry seasons on productivity was found. Additionally, in the hen harrier, the proportion of eggs that did not hatch in each clutch increased with higher temperatures during the incubation period. No such relationship was found in the Montagu's harrier. We interpret these between-species differences in terms of differences of breeding range and adaptations to the average conditions existing there. Hen harriers, commonest at northern latitudes, are probably best adapted to the most typical conditions at those latitudes, and have probably not developed thermoregulatory or behavioural mechanisms to cope with drought and high temperatures in Mediterranean habitats, in contrast to Montagu's harrier. Thus hen harrier distribution might be constrained by these variables, due to lower reproductive success or higher reproductive costs. Accordingly, a logistic regression analysis of the presence or absence of both species in 289 random points throughout the western Palearctic showed that the distribution of both species was related to temperature, but the relationship was in opposite directions for the two species: hen harriers had lower probability of breeding in areas with higher temperature (as expected in a species with a more northerly distribution). [source] The effect of past changes in inter-annual temperature variability on tree distribution limitsJOURNAL OF BIOGEOGRAPHY, Issue 7 2010Thomas Giesecke Abstract Aim, The northern limits of temperate broadleaved species in Fennoscanndia are controlled by their requirements for summer warmth for successful regeneration and growth as well as by the detrimental effects of winter cold on plant tissue. However, occurrences of meteorological conditions with detrimental effects on individual species are rare events rather than a reflection of average conditions. We explore the effect of changes in inter-annual temperature variability on the abundances of the tree species Tilia cordata, Quercus robur and Ulmus glabra near their distribution limits using a process-based model of ecosystem dynamics. Location, A site in central Sweden and a site in southern Finland were used as examples for the ecotone between boreal and temperate forests in Fennoscandia. The Finnish site was selected because of the availability of varve-thickness data. Methods, The dynamic vegetation model LPJ-GUESS was run with four scenarios of inter-annual temperature forcing for the last 10,000 years. In one scenario the variability in the thickness of summer and winter varves from the annually laminated lake in Finland was used as a proxy for past inter-annual temperature variability. Two scenarios were devised to explore systematically the effect of stepwise changes in the variance and shape parameter of a probability distribution. All variability scenarios were run both with and without the long-term trend in Holocene temperature change predicted by an atmospheric general circulation model. Results, Directional changes in inter-annual temperature variability have significant effects on simulated tree distribution limits through time. Variations in inter-annual temperature variability alone are shown to alter vegetation composition by magnitudes similar to the magnitude of changes driven by variation in mean temperatures. Main conclusions, The varve data indicate that inter-annual climate variability has changed in the past. The model results show that past changes in species abundance can be explained by changes in the inter-annual variability of climate parameters as well as by mean climate. Because inter-annual climatic variability is predicted to change in the future, this component of climate change should be taken into account both when making projections of future plant distributions and when interpreting vegetation history. [source] Luminous red galaxy clustering at z, 0.7 , first results using AAOmegaMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 3 2008Nicholas P. Ross ABSTRACT We report on the AAT-AAOmega LRG Pilot observing run to establish the feasibility of a large spectroscopic survey using the new AAOmega instrument. We have selected luminous red galaxies (LRGs) using single epoch SDSS riz -photometry to i < 20.5 and z < 20.2. We have observed in three fields including the COSMOS field and the COMBO-17 S11 field, obtaining a sample of ,600 redshift z, 0.5 LRGs. Exposure times varied from 1,4 h to determine the minimum exposure for AAOmega to make an essentially complete LRG redshift survey in average conditions. We show that LRG redshifts to i < 20.5 can be measured in ,1.5 h exposures and present comparisons with 2SLAQ and COMBO-17 (photo)redshifts. Crucially, the riz selection coupled with the three to four times improved AAOmega throughput is shown to extend the LRG mean redshift from z= 0.55 for 2SLAQ to z= 0.681 ± 0.005 for riz -selected LRGs. This extended range is vital for maximizing the signal-to-noise ratio for the detection of the baryon acoustic oscillations (BAOs). Furthermore, we show that the amplitude of LRG clustering is s0= 9.9 ± 0.7h,1 Mpc, as high as that seen in the 2SLAQ LRG Survey. Consistent results for this clustering amplitude are found from the projected and semi-projected correlation functions. This high amplitude is consistent with a long-lived population whose bias evolves as predicted by a simple ,high-peak' model. We conclude that a redshift survey of 360 000 LRGs over 3000 deg2, with an effective volume some four times bigger than previously used to detect BAO with LRGs, is possible with AAOmega in 170 nights. [source] Convective Available Potential Energy (CAPE) in mixed phase cloud conditionsTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 624 2007B. Früh Abstract An approximate but pragmatic approach is presented to define Convective Available Potential Energy (CAPE) in mixed phase cloud conditions. The underlying process calls for mixed (i.e. liquid and ice) phase parcels and assumes the liquid fraction to be a unique function of temperature. The approach is meant to represent average conditions. Differences between this and more traditional approaches are quantified and discussed for mean tropical conditions. Generally freezing increases parcel temperature and, hence, buoyancy. If freezing occurs isobarically (as was often assumed in the past), all water changes phase at a single level resulting in a discontinuity in buoyancy at that level. By contrast, the mixed phase parcel process implies a continuous phase transition in a finite range of temperatures Tfs , T , Tfe, leading to a gradual change of buoyancy with altitude and preventing any temperature inversion. The details of this gradual change depend on the choice of the specified temperature range [Tfs, Tfe]. High in the troposphere, where all water is frozen irrespective of the details, the differences between the buoyancy profiles are small (but finite). CAPE is very sensitive to the treatment of the freezing process. Isobaric freezing at a relatively high temperature (e.g. , 5 °C) in a reversible process may increase CAPE by a factor of 2 to 3, and this increase is similar in magnitude to the difference between the pseudo-adiabatic and the reversible processes for pure water parcels. Both of these processes are considered less realistic than the reversible mixed phase process with continuous freezing over a broad temperature range [Tfs, Tfe] = [,5 °C, , 40 °C]; the corresponding CAPE lies about half way between the reversible and irreversible pure water processes. For clouds with finite precipitation efficiency the effect of freezing is less pronounced than for reversible conditions. Copyright © 2007 Royal Meteorological Society [source] The importance of experimental design in detecting the effects of protection measures on fish in Mediterranean MPAsAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 6 2002P. Guidetti Abstract 1.Marine Protected Areas (MPAs) are currently proliferating in the Mediterranean Sea. The assessment of their role in the protection and recovery of overexploited fish populations, however, is not yet completely supported by an adequate body of scientific evidence. This is in part because the number of studies that unambiguously assess changes induced by protection is limited. 2.Sampling to detect and measure the expected effects of protection on commercial fish (e.g. increase in mean abundance and size) is made difficult by intrinsic natural spatial and temporal variability. Ideally, temporal replication before and after the establishment of MPAs is necessary for estimating the average conditions in time. Spatial replication of control locations, on the other hand, is essential to prevent confusion in interpreting a difference between protected and unprotected locations. Until now, the basic requirements for appropriate experimental designs in MPAs were seldom satisfied, especially in the Mediterranean region. 3.In the present paper, an ideal experimental design aimed at overcoming many of the confounding influences that could result in misinterpretations of the results is considered, with a discussion of implications of applying less and less appropriate designs because of pragmatic constraints. Experimental design should thus be adapted to each individual MPA under study on the basis of the specific constraints that researchers face (e.g. ,before' (i.e. pre-designation) data are lacking; there is a single or more than one protected locations). 4.The issues related to MPAs, chiefly in the Mediterranean region, need to be considered to enable the identification of unambiguous hypotheses prior to sampling, based on clear logical structures. The importance of appropriate sampling and the subsequent interpretation of data would progressively reduce the degree of uncertainty of environmental analyses about the effects of MPAs on fish, with important implications for their management and further proliferation. Copyright © 2002 John Wiley & Sons, Ltd. [source] | ||||||||||