bluuebunny/crossref_metadata_2025_split huggingface dataset:
Menstrual cycle symptoms are associated with changes in low‐grade inflammation
Authors: Puder J. J. , Blum C. A. , Mueller B. , De Geyter Ch. , Dye L. , Keller U. 
Published: December 2005

AbstractBackground  A close link between mood, low‐grade inflammation and obesity has been demonstrated even in healthy subjects. We investigated the relationship between changes in physical and psychological symptoms and inflammatory markers during the menstrual cycle both in normal weight and in overweight women.Materials and methods  Eight healthy normal weight (body mass index 21·6 ± 1·9 kg m−2) and seven overweight (body mass index 30 ± 2·4 kg m−2) young women with normal ovarian function and with no premenstrual syndrome were assessed 15 times throughout their menstrual cycle. At each time point fasting blood was drawn and symptoms were recorded using the Freeman Daily Symptom Record.Results  Independent of weight status, the serum concentrations of highly sensitive C‐reactive protein (hs‐CRP) and the total scores, in addition to the individual four factors (mood, behaviour, pain and physical symptoms), of the Daily Symptom Record varied significantly during the menstrual cycle (all P ≤ 0·04) and paralleled each other. During the menstrual cycle, repeated hs‐CRP serum concentrations correlated to the corresponding total symptom score and the factors mood, behaviour and physical symptoms, independent of both weight status and changes in circulating gonadal steroids (all P ≤ 0·04). These associations were not observed for tumour necrosis factor‐α serum levels. The mean hs‐CRP concentrations were associated with the mean total symptom score, independent of weight status (r = 0·56, P = 0·04).Conclusion  Healthy young women showed psychological and physical symptoms during the menstrual cycle which changed in association with alterations in low‐grade inflammation and which were independent of body weight or plasma levels of gonadal steroids.
The effect of temperature on photoperiodically regulated gonadal maturation, regression and moult in starlings – potential consequences of climate change
Authors: DAWSON A. 
Published: December 2005

Summary

Birds use increasing photoperiod during spring as the major cue to time gonadal maturation and breeding so that nestlings are growing during peak food (normally invertebrate) abundance. Climate warming will advance invertebrate abundance, so birds relying entirely on photoperiod will breed too late. Can temperature modulate responses to photoperiod?
Common Starlings, Sturnus vulgaris, were kept in two indoor aviaries, in which photoperiod tracked natural changes, but temperature was held at either 20 °C or 5 °C (year 1), or at 18 °C or 8 °C (year 2).
Despite the large differences in temperature (15 °C and 10 °C), this had no effect on the rate or timing of testicular maturation.
However, unexpectedly, testicular regression occurred significantly earlier at the higher temperatures. Post‐nuptial moult also started significantly earlier in both males and females.
Therefore, the degree to which birds can advance the timing of egg‐laying in response to increasing spring temperature may be constrained. At the same time, increasing spring temperature will advance the end of the breeding season (fewer breeding attempts). The reported advances in median egg‐laying dates may, in part, be a consequence of this rather than an indication of successful adaptation. Adaptation to climate change may require evolutionary changes in the physiological responses to photoperiod.
Effect of pretreatments and freezing rate on the firmness of potato tissue after a freeze–thaw cycle
Authors: Carbonell Sergio , Oliveira Jorge C. , Kelly Alan L. 
Published: December 2005

SummaryThe texture of potato tissue after a freeze–thaw process using different freezing rates and different pretreatments was analysed, in order to select the best strategy for optimum preservation of the textural characteristics of pre‐frozen potato. Ten blanching conditions were tested and a two‐step blanching process with calcium chloride (0.07 g mL−1) proved the most effective in protecting the tissue after a freeze–thaw process (maximum load force around 10–55% of the raw tissue, depending on potato batch, for air‐blast freezing and 20–60% for immersion freezing). Vacuum impregnation at 100 and 400 mbar, even when followed by different pre‐drying treatments to remove excess water, was very detrimental to resistance to a freeze–thaw process (maximum load force below 10% of the raw tissue for air‐blast freezing and below 20% for immersion freezing). Microstructure analysis confirmed better tissue integrity retention with ethyleneglycol immersion freezing instead of air‐freezing. Differences were found between batches with a 6‐month difference in storage time, indicating that the fresher batch was more suitable for freezing.
Climate and spatio‐temporal variation in the population dynamics of a long distance migrant, the white stork
Authors: SÆTHER BERNT‐ERIK , GRØTAN VIDAR , TRYJANOWSKI PIOTR , BARBRAUD CHRISTOPHE , ENGEN STEINAR , FULIN MIROSLAV 
Published: December 2005

SummaryA central question in ecology is to separate the relative contribution of density dependence and stochastic influences to annual fluctuations in population size. Here we estimate the deterministic and stochastic components of the dynamics of different European populations of white storkCiconia ciconia. We then examined whether annual changes in population size was related to the climate during the breeding period (the ‘tap hypothesis’sensuSæther, Sutherland & Engen (2004,Advances in Ecological Research,35, 185–209) or during the nonbreeding period, especially in the winter areas in Africa (the ‘tube hypothesis’).A general characteristic of the population dynamics of this long‐distance migrant is small environmental stochasticity and strong density regulation around the carrying capacity with short return times to equilibrium.Annual changes in the size of the eastern European populations were correlated by rainfall in the wintering areas in Africa as well as local weather in the breeding areas just before arrival and in the later part of the breeding season and regional climate variation (North Atlantic Oscillation). This indicates that weather influences the population fluctuations of white storks through losses of sexually mature individuals as well as through an effect on the number of individuals that manages to establish themselves in the breeding population. Thus, both the tap and tube hypothesis explains climate influences on white stork population dynamics.The spatial scale of environmental noise after accounting for the local dynamics was 67 km, suggesting that the strong density dependence reduces the synchronizing effects of climate variation on the population dynamics of white stork.Several climate variables reduced the synchrony of the residual variation in population size after accounting for density dependence and demographic stochasticity, indicating that these climate variables had a synchronizing effect on the population fluctuations. In contrast, other climatic variables acted as desynchronizing agents.Our results illustrate that evaluating the effects of common environmental variables on the spatio‐temporal variation in population dynamics require estimates and modelling of their influence on the local dynamics.
Effects of neighbourhood structure and tussock dynamics on genet demography of Festuca rubra in a mountain meadow
Authors: SUZUKI JUN‐ICHIROU , HERBEN TOMÁŠ , KRAHULEC FRANTIŠEK , ŠTORCHOVÁ HELENA , HARA TOSHIHIKO 
Published: December 2005

Summary

We examined whether genet demography in the clonal grass Festuca rubra in a mountain grassland in the Krkonoše Mountains (Czech Republic) changes in response to local environment. The data were also used to compare genet recruitment with estimates of genet mortality.
We sampled F. rubra from four permanent plots in which ramet densities of all species have been recorded at a fine scale for a decade. Identities of 224 ramets were assessed by means of RAPD, yielding 145 different genets, of which most (68%) were found only once. The genet with the highest number of sampled ramets was recorded nine times.
By assuming that the probability that two ramets are genetically identical is a function of distance between ramets, we estimated that successful seedling recruitment rates were between 0.15 and 16 genets m−2 yr−1 depending on the plot. Genet mortality was estimated from ramet mortality using the assumption that ramet mortality was uncorrelated over space. In three of the four plots, genet mortalities fell into the same range as the genet recruitment rates.
The total number of genets per unit area must be known to enable determination of per capita recruitment and mortality rates. We developed an estimation technique involving simulation of the sampling process, which yielded values of 231–968 genets m−2. Genet turnover was therefore low (0.1–1% annually) and the high genet diversity is maintained by a very low recruitment.
Spatial analysis showed that two ramets were more likely to be genetically identical when they came from a microhabitat where Festuca ramet density had recently increased; patches in which Festuca ramet density had decreased were more likely to contain ramets from several genets. Expanding tussocks are thus more likely to be composed of ramets of one genet only. Density and biomass of other species in the neighbourhood showed little correlation with the genet structure of Festuca rubra.
Although ramets of Festuca rubra intermingle with other species at a fine scale, the population biology of its genets is driven mainly by the dynamics of its own ramets. Interactions with other species and response to local environments have little effect on genet structure.
Beta diversity and the scale‐dependence of the productivity‐diversity relationship: a test in the Californian serpentine flora
Authors: HARRISON SUSAN , DAVIES KENDI F. , SAFFORD HUGH D. , VIERS JOSHUA H. 
Published: December 2005

Summary

The relationship of productivity to species diversity is usually positive at regional scales, but is often neutral, unimodal or negative at local spatial scales. Recent studies have pointed out that beta diversity, or among‐locality and within‐region variation in species composition, must therefore tend to increase with productivity.
We tested for a positive relationship of productivity to beta diversity in herbaceous plants at 105 widely distributed sites on serpentine soil in California. We also asked whether any such pattern could be explained, as previously proposed, by increased environmental heterogeneity at higher levels of productivity.
We found that one measure of beta diversity (the species dissimilarity between paired 500 m2 plots on adjacent north and south slopes) was positively related to productivity (as measured by the normalized difference vegetation index, a remotely sensed index). However, this effect was not strong enough to transform the neutral relationship of productivity with alpha (1 m2) diversity to a positive relationship of productivity with gamma (1000 m2) diversity.
The positive effect of productivity on beta diversity was not related to increasing heterogeneity in coarse measures of vegetation structure (percentage cover of shade, litter, rocks, moss, bare soil, animal disturbance). We speculate that the effect may instead have a ‘top‐down’ explanation: higher beta diversity may be caused by the positive influence of productivity on the size of the regional species pool.
Our study illustrates the principle of a ‘scale transition’, in which an ecological pattern is qualitatively different at different spatial scales. Careful attention to scale‐dependence may help narrow the search for mechanisms for such long‐studied ecological puzzles as the latitudinal diversity gradient.
Predictors of asphyxiation risk in adults with intellectual disabilities and dysphagia
Authors: Samuels R. , Chadwick D. D. 
Published: December 2005

AbstractBackground Adults with learning disabilities referred for assessment of their eating and drinking are frequently reported to cough and choke when eating and drinking. The research literature investigating dysphagia has often overlooked asphyxiation risk, highlighting coughing and choking as indicators of aspiration only. This is a notable oversight due to the prevalence of asphyxia as a cause of mortality in this population.Aim This study aims to identify the physiological and environmental factors that predict asphyxiation risk in adults with intellectual disabilities and dysphagia.Method Data were collected from dysphagia‐trained speech and language therapists (SLTs) working with the participant adults with intellectual disabilities and dysphagia. The SLTs used case notes, clinical assessment and videofluoroscopic assessment reports to gather the data.Results Speed of eating, cramming food and premature loss of the bolus into the pharynx were identified as significant predictors of asphyxiation risk in this population.Conclusions The findings highlight the importance of maladaptive eating strategies in exacerbating the risk of asphyxiation and choking. These factors should be considered in the assessment of asphyxiation and choking risk and management. Finally, the need for joint assessment and management with other members of the multidisciplinary team is advocated.
Practical modelling of porous media from second‐order statistics: the phase‐retrieval problem and the interpretation of the covariance
Authors: ANGUY YANNICK , LE TRONG EMMANUEL , EHRLICH ROBERT 
Published: December 2005

SummaryIn many disciplines, binary numerical porous media are commonly generated as realizations of a random process characterized by a limited set of morphological measurements, e.g. the conditioning and truncated Gaussian random field (GRF) model or the Monte Carlo simulated annealing (SA) reconstruction. Whether the output microstructures of a model are quantitative or qualitative depends largely on the information carried by the constraints that are implemented. We focus on the standard two‐point correlation function, also referred to as the covariance. The isotropic situation has been previously extensively studied. Here, we concentrate on a vector distance‐dependent covariance. Relying on practical solutions to the phase‐retrieval problem (retrieving an object from its Fourier modulus) encountered in general imaging, we show empirically that a finite binary two‐ or three‐dimensional actual sample can be recovered systematically to within a pixel from its correlation integral (the volume average covariance to within a scale factor). In random modelling, this characteristic, describing uniquely a single sample of finite size, must be simplified, i.e. reduced to its statistical content, prior to be fitted in a random model (GRF, SA) as the characteristic of a series of realizations of a porous medium. We consider a common simplification, i.e. truncation, in which that part of the covariance relating to the small‐scale features of the observed sample is preserved only. This arbitrary simplification is empirically supported by numerous published numerical experiments showing that the small‐scale content of a volume‐averaged covariance can be fairly well reproduced in realizations of various random models: its statistical nature is thus illustrated with the GRF model. The unique solution to the phase‐retrieval problem confers an important sense to this numerical agreement: the correlation integral being the most complete descriptor, the actual sample and the model outputs are considered as true analogues over scales smaller or equal to the cutoff length attached to the truncation. Thus, awareness of the phase‐retrieval problem supports on an empirical basis the generation of synthetic binary objects from a direct measurement on an available sample.
Studies on depth‐of‐field effects in microscopy supported by numerical simulations
Authors: OVERBY DARRYL R. , JOHNSON MARK 
Published: December 2005

SummaryMicrographs are two‐dimensional (2D) representations of three‐dimensional (3D) objects. When the depth‐of‐field of a micrograph is comparable with or larger than the characteristic dimension of objects within the micrograph, measured 2D parameters (e.g. particle number density, surface area of particles, fraction of open space) require stereological correction to determine the correct 3D values. Here, we develop a stereological theory using a differential approach to relate the 3D volume fraction and specific surface area to the 2D projected area and perimeter fractions, accounting for the influence of depth‐of‐field. The stereological theory is appropriate for random isotropic arrangements of non‐interpenetrating particles and is valid for convex geometries (e.g. spheres, spheroids, cylinders). These geometrical assumptions allow the stereological formulae to be expressed as a set of algebraic equations incorporating a single parameter to describe particle shape that is tightly bounded between 1.5π and 2π. The stereological theory may also be applied to arrangements of interpenetrating convex particles, and for this case, the resulting stereological formulae become identical to the formulae previously presented by Miles. To test the accuracy of the stereological theory, random computational arrangements of non‐interpenetrating and interpenetrating spheres or cylinders are analysed, and the projected area and perimeter fractions are numerically determined as a function of depth‐of‐field. The computational results show very good agreement with the theoretical predictions over a broad range of depth‐of‐field, volume fraction and particle geometry for both non‐interpenetrating and interpenetrating particles, demonstrating the overall accuracy of the stereological theory. Applications of the stereological theory towards analysis of biological tissues and extracellular matrix are discussed.
Tracking quasi‐stationary flow of weak fluorescent signals by adaptive multi‐frame correlation
Authors: JI L. , DANUSER G. 
Published: December 2005

SummaryWe have developed a novel cross‐correlation technique to probe quasi‐stationary flow of fluorescent signals in live cells at a spatial resolution that is close to single particle tracking. By correlating image blocks between pairs of consecutive frames and integrating their correlation scores over multiple frame pairs, uncertainty in identifying a globally significant maximum in the correlation score function has been greatly reduced as compared with conventional correlation‐based tracking using the signal of only two consecutive frames. This approach proves robust and very effective in analysing images with a weak, noise‐perturbed signal contrast where texture characteristics cannot be matched between only a pair of frames. It can also be applied to images that lack prominent features that could be utilized for particle tracking or feature‐based template matching. Furthermore, owing to the integration of correlation scores over multiple frames, the method can handle signals with substantial frame‐to‐frame intensity variation where conventional correlation‐based tracking fails. We tested the performance of the method by tracking polymer flow in actin and microtubule cytoskeleton structures labelled at various fluorophore densities providing imagery with a broad range of signal modulation and noise. In applications to fluorescent speckle microscopy (FSM), where the fluorophore density is sufficiently low to reveal patterns of discrete fluorescent marks referred to as speckles, we combined the multi‐frame correlation approach proposed above with particle tracking. This hybrid approach allowed us to follow single speckles robustly in areas of high speckle density and fast flow, where previously published FSM analysis methods were unsuccessful. Thus, we can now probe cytoskeleton polymer dynamics in living cells at an entirely new level of complexity and with unprecedented detail.
Dissociation of basal dislocations in hexagonal barium titanate
Authors: WU Y. C. , HO N. J. , LU H. Y. 
Published: December 2005

SummaryDislocation substructure in hot‐pressed hexagonal BaTiO3 ceramics was analysed by transmission electron microscopy. Two dislocation networks each consisting of dissociated half‐partials were determined for the Burgers vectors (b) using the g · b = 0 effective invisibility criteria, and the true directions (u) by trace analysis. Each of the networks contains three partial nodes that are in the form: 1/3[010]+1/3[100]+1/3[100]+1/3[100] = 0, where four partials meet at a point and the Burgers vectors are conserved, as analysed by the weak‐beam dark field technique. Basal dislocation with bb = 1/3<110> is dissociated into two prism plane half‐partials with bhp = 1/3<100> by: 1/3<110> → 1/3<010> + 1/3<100>. Dissociation of basal dislocation by a glide mechanism creates a stacking fault when shear occurs along <100> in the c‐layer of (000l), where l = 1, 3, 4 and 6, of the (chc)1(chc)2 (or (CBC)(ABA)) stacking sequence. The slip system of 1/3<110>(0001) in hexagonal BaTiO3 has been activated at 1300 °C by hot‐pressing under ∼25.8 MPa. Plastic flow contributing to the densification of hexagonal BaTiO3 ceramics occurs through glide of half‐partials in the basal plane by a glide‐controlled dislocation glide mechanism. Dislocation motion governed by the Peierls mechanism, where velocity is determined by both correlated and uncorrelated double‐kink nucleation on two half‐partials, is discussed.
Gene lineages and eastern North American palaeodrainage basins: phylogeography and speciation in salamanders of the Eurycea bislineata species complex
Authors: KOZAK KENNETH H. , BLAINE RUSSELL A. , LARSON ALLAN 
Published: December 2005

sAbstractContemporary North American drainage basins are composites of formerly isolated drainages, suggesting that fragmentation and fusion of palaeodrainage systems may have been an important factor generating current patterns of genetic and species diversity in stream‐associated organisms. Here, we combine traditional molecular‐phylogenetic, multiple‐regression, nested clade, and molecular‐demographic analyses to investigate the relationship between phylogeographic variation and the hydrogeological history of eastern North American drainage basins in semiaquatic plethodontid salamanders of the Eurycea bislineata species complex. Four hundred forty‐two sequences representing 1108 aligned bases from the mitochondrial genome are reported for the five formally recognized species of the E. bislineata complex and three outgroup taxa. Within the ingroup, 270 haplotypes are recovered from 144 sampling locations. Geographic patterns of mtDNA‐haplotype coalescence identify 13 putatively independent population‐level lineages, suggesting that the current taxonomy of the group underestimates species‐level diversity. Spatial and temporal patterns of phylogeographic divergence are strongly associated with historical rather than modern drainage connections, indicating that shifts in major drainage patterns played a pivotal role in the allopatric fragmentation of populations and build‐up of lineage diversity in these stream‐associated salamanders. More generally, our molecular genetic results corroborate geological and faunistic evidence suggesting that palaeodrainage connections altered by glacial advances and headwater erosion occurring between the mid‐Miocene and Pleistocene epochs explain regional patterns of biodiversity in eastern North American streams.