bluuebunny/crossref_metadata_2025 huggingface dataset:
Trophic eggs compensate for poor offspring feeding capacity in a subsocial burrower bug
Authors: Baba Narumi , Hironaka Mantaro , Hosokawa Takahiro , Mukai Hiromi , Nomakuchi Shintaro , Ueno Takatoshi
Published: September 2010

Various animals produce inviable eggs or egg-like structures called trophic eggs, which are presumed to be an extended maternal investment for the offspring. However, there is little knowledge about the ecological or physiological constraints associated with their evolutionary origin. Trophic eggs of the seminivorous subsocial burrower bug (Canthophorus niveimarginatus) have some unique characteristics. Trophic eggs are obligate for nymphal survival, and first-instar nymphs die without them. To identify the cause of nymphal death, we hypothesized that first-instar nymphs starve to death because they cannot feed on anything but trophic eggs. Although first-instar nymphs fed on artificially exposed endosperm did survive, nymphs that were provided with intact seed were not able to penetrate the seed vessel and starved to death. Another hypothesis that trophic eggs play a role in transferring the midgut symbiont, essential for survival in heteropteran bugs, from mother to offspring was rejected because almost all nymphs had retained the symbiont without feeding on trophic eggs. These results suggest that poor feeding capacity of the offspring is the cause of nymphal death, and the important constraint that promotes the evolution of the curious trophic egg system inC. niveimarginatus.
Antimicrobial strength increases with group size: implications for social evolution
Authors: Turnbull Christine , Hoggard Stephen , Gillings Michael , Palmer Chris , Stow Adam , Beattie Doug , Briscoe David , Smith Shannon , Wilson Peter , Beattie Andrew
Published: September 2010

We hypothesize that aggregations of animals are likely to attract pathogenic micro-organisms and that this is especially the case for semisocial and eusocial insects where selection ultimately led to group sizes in the thousands or even millions, attracting the epithet ‘superorganism’. Here, we analyse antimicrobial strength, per individual, in eight thrips species (Insecta: Thysanoptera) that present increasing innate group sizes and show that species with the largest group size (100–700) had the strongest antimicrobials, those with smaller groups (10–80) had lower antimicrobial activity, while solitary species showed none. Species with large innate group sizes showed strong antimicrobial activity while the semisocial species showed no activity until group size increased sufficiently to make activity detectable. The eusocial species behaved in a similar way, with detectable activity appearing once group size exceeded 120. These analyses show that antimicrobial strength is determined by innate group size. This suggests that the evolution of sociality that, by definition, increases group size, may have had particular requirements for defences against microbial pathogens. Thus, increase in group size, accompanied by increased antibiotic strength, may have been a critical factor determining the ‘point of no return’, early in the evolution of social insects, beyond which the evolution of social anatomical and morphological traits was irreversible. Our data suggest that traits that increase group size in general are accompanied by increased antimicrobial strength and that this was critical for transitions from solitary to social and eusocial organization.
Light enough to travel: migratory bats have smaller brains, but not larger hippocampi, than sedentary species
Authors: McGuire Liam P. , Ratcliffe John M.
Published: September 2010

Migratory bird species have smaller brains than non-migratory species. The behavioural flexibility/migratory precursor hypothesis suggests that sedentary birds have larger brains to allow the behavioural flexibility required in a seasonally variable habitat. The energy trade-off hypothesis proposes that brains are heavy, energetically expensive and therefore, incompatible with migration. Here, we compared relative brain, neocortex and hippocampus volume between migratory and sedentary bats at the species-level and using phylogenetically independent contrasts. We found that migratory bats had relatively smaller brains and neocortices than sedentary species. Our results support the energy trade-off hypothesis because bats do not exhibit the same degree of flexibility in diet selection as sedentary birds. Our results also suggest that bat brain size differences are subtler than those found in birds, perhaps owing to bats' shorter migration distances. Conversely, we found no difference in relative hippocampus volume between migratory and sedentary species, underscoring our limited understanding of the role of the hippocampus in bats.
Plant signalling: the opportunities and dangers of chemical communication
Authors: Adler Frederick R.
Published: September 2010

The notion of chemical communication between plants and other organisms has gone from being viewed as a fringe idea to an accepted ecological phenomenon only recently. An Organized Oral Session at the August 2010 Ecological Society of America meeting in Pittsburgh examined the role of plant signalling both within and between plants, with speakers addressing the remarkably wide array of effects that plant signals have on plant physiology, species interactions and entire communities. In addition to the familiar way that plants communicate with mutualists like pollinators and fruit dispersers through both chemical and visual cues, speakers at this session described how plants communicate with themselves, with each other, with herbivores and with predators of those herbivores. These plant signals create a complex odour web superimposed upon the more classical food web itself, with its own dynamics in the face of exotic species and rapid community assembly and disassembly.
Tumorigenicity of pluripotent stem cells: biological insights from molecular imaging
Authors: Kooreman Nigel G. , Wu Joseph C.
Published: September 2010

Embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) have the ability (i) to duplicate indefinitely while maintaining pluripotency and (ii) to differentiate into cell types of all three embryonic germ layers. These two properties of ESCs and iPSCs make them potentially suitable for tissue engineering and cell replacement therapy for many different diseases, including Parkinson's disease, diabetes and heart disease. However, one critical obstacle in the clinical application of ESCs or iPSCs is the risk of teratoma formation. The emerging field of molecular imaging is allowing researchers to track transplanted ESCs or iPSCs
in vivo
, enabling early detection of teratomas.
Nano-Ag-loaded hydroxyapatite coatings on titanium surfaces by electrochemical deposition
Authors: Lu Xiong , Zhang Bailin , Wang Yingbo , Zhou Xianli , Weng Jie , Qu Shuxin , Feng Bo , Watari Fumio , Ding Yonghui , Leng Yang
Published: September 2010

Hydroxyapatite (HA) coatings on titanium (Ti) substrates have attracted much attention owing to the combination of good mechanical properties of Ti and superior biocompatibility of HA. Incorporating silver (Ag) into HA coatings is an effective method to impart the coatings with antibacterial properties. However, the uniform distribution of Ag is still a challenge and Ag particles in the coatings are easy to agglomerate, which in turn affects the applications of the coatings. In this study, we employed pulsed electrochemical deposition to co-deposit HA and Ag simultaneously, which realized the uniform distribution of Ag particles in the coatings. This method was based on the use of a well-designed electrolyte containing Ag ions, calcium ions and
l
-cysteine, in which cysteine acted as the coordination agent to stabilize Ag ions. The antibacterial and cell culture tests were used to evaluate the antibacterial properties and biocompatibility of HA/Ag composite coatings, respectively. The results indicated the as-prepared coatings had good antibacterial properties and biocompatibility. However, an appropriate silver content should be chosen to balance the biocompatibility and antibacterial properties. Heat treatments promoted the adhesive strength and enhanced the biocompatibility without sacrificing the antibacterial properties of the HA/Ag coatings. In summary, this study provided an alternative method to prepare bioactive surfaces with bactericidal ability for biomedical devices.
A simple expression for fluid inertia force acting on micro-plates undergoing squeeze film damping
Authors: Huang Shujuan , Borca-Tasciuc Diana-Andra , Tichy John A.
Published: September 2010

Squeeze film damping in systems employing micro-plates parallel to a substrate and undergoing small normal vibrations is theoretically investigated. In high-density fluids, inertia forces may play a significant role affecting the dynamic response of such systems. Previous models of squeeze film damping taking inertia into account do not clearly isolate this effect from viscous damping. Therefore, currently, there is no simple way to distinguish between these two hydrodynamic effects. This paper presents a simple solution for the hydrodynamic force acting on a plate vibrating in an incompressible fluid, with distinctive terms describing inertia and viscous damping. Similar to the damping constant describing viscous losses, an inertia constant, given by
ρL
3
W
/
h
(where
ρ
is fluid density,
L
and
W
are plate length and width, respectively, and
h
is separation distance), may be used to accurately calculate fluid inertia for small oscillation Reynolds numbers. In contrast with viscous forces that suppress the amplitude of the oscillation, it is found that fluid inertia acts as an added mass, shifting the natural frequency of the system to a lower range while having little effect on the amplitude. Dimensionless parameters describing the relative importance of viscous and inertia effects also emerge from the analysis.
Effects of weather and climate on the dynamics of animal population time series
Authors: Knape Jonas , de Valpine Perry
Published: September 2010

Weather is one of the most basic factors impacting animal populations, but the typical strength of such impacts on population dynamics is unknown. We incorporate weather and climate index data into analysis of 492 time series of mammals, birds and insects from the global population dynamics database. A conundrum is that a multitude of weather data may
a priori
be considered potentially important and hence present a risk of statistical over-fitting. We find that model selection or averaging alone could spuriously indicate that weather provides strong improvements to short-term population prediction accuracy. However, a block randomization test reveals that most improvements result from over-fitting. Weather and climate variables do, in general, improve predictions, but improvements were barely detectable despite the large number of datasets considered. Climate indices such as North Atlantic Oscillation are not better predictors of population change than local weather variables. Insect time series are typically less predictable than bird or mammal time series, although all taxonomic classes display low predictability. Our results are in line with the view that population dynamics is often too complex to allow resolving mechanisms from time series, but we argue that time series analysis can still be useful for estimating net environmental effects.
Optimal antiviral treatment strategies and the effects of resistance
Authors: Hansen Elsa , Day Troy
Published: September 2010

Recent pandemic planning has highlighted the importance of understanding the effect that widespread antiviral use will have on the emergence and spread of resistance. A number of recent studies have determined that if resistance to antiviral medication can evolve, then deploying treatment at a less than maximum rate often minimizes the outbreak size. This finding, however, involves the assumption that treatment levels remain constant during the entire outbreak. Using optimal control theory, we address the question of optimal antiviral use by considering a large class of time-varying treatment strategies. We prove that, contrary to previous results, it is always optimal to treat at the maximum rate provided that this treatment occurs at the right time. In general the optimal strategy is to wait some fixed amount of time and then to deploy treatment at the maximum rate for the remainder of the outbreak. We derive analytical conditions that characterize this optimal amount of delay. Our results show that it is optimal to start treatment immediately when one of the following conditions holds: (i) immediate treatment can prevent an outbreak, (ii) the initial pool of susceptibles is small, or (iii) when the maximum possible rate of treatment is low, such that there is little de novo emergence of resistant strains. Finally, we use numerical simulations to verify that the results also hold under more general conditions.
Internal incubation and early hatching in brood parasitic birds
Authors: Birkhead T. R. , Hemmings N. , Spottiswoode C. N. , Mikulica O. , Moskát C. , Bán M. , Schulze-Hagen K.
Published: September 2010

The offspring of brood parasitic birds benefit from hatching earlier than host young. A proposed but little-known strategy to achieve this is ‘internal incubation’, by retaining the egg in the oviduct for an additional 24 h. To test this, we quantified the stage of embryo development at laying in four brood parasitic birds (European cuckoo,Cuculus canorus; African cuckoo,Cuculus gularis; greater honeyguide,Indicator indicator; and the cuckoo finch,Anomalospiza imberbis). For the two cuckoos and the honeyguide, all of which lay at 48 h intervals, embryos were at a relatively advanced stage at laying; but for the cuckoo finch (laying interval: 24 h) embryo stage was similar to all other passerines laying at 24 h intervals. The stage of embryo development in the two cuckoos and honeyguide was similar to that of a non-parasitic species that lay at an interval of 44–46 h, but also to the eggs of the zebra finchTaeniopygia guttataincubated artificially at body temperature immediately after laying, for a further 24 h. Comparison with the zebra finch shows that internal incubation in the two cuckoos and honeyguide advances hatching by 31 h, a figure consistent with the difference between the expected and the observed duration of incubation in the European cuckoo predicted from egg mass. Rather than being a specific adaptation to brood parasitism, internal incubation is a direct consequence of a protracted interval between ovulation (and fertilization) and laying, but because it results in early hatching may have predisposed certain species to become brood parasitic.
Remarkable morphological stasis in an extant vertebrate despite tens of millions of years of divergence
Authors: Lavoué Sébastien , Miya Masaki , Arnegard Matthew E. , McIntyre Peter B. , Mamonekene Victor , Nishida Mutsumi
Published: September 2010

The relationship between genotypic and phenotypic divergence over evolutionary time varies widely, and cases of rapid phenotypic differentiation despite genetic similarity have attracted much attention. Here, we report an extreme case of the reverse pattern—morphological stasis in a tropical fish despite massive genetic divergence. We studied the enigmatic African freshwater butterfly fish (
Pantodon buchholzi
), whose distinctive morphology earns it recognition as a monotypic family. We sequenced the mitochondrial genome of
Pantodon
from the Congo basin and nine other osteoglossomorph taxa for comparison with previous mitogenomic profiles of
Pantodon
from the Niger basin and other related taxa.
Pantodon
populations form a monophyletic group, yet their mitochondrial coding sequences differ by 15.2 per cent between the Niger and Congo basins. The mitogenomic divergence time between these populations is estimated to be greater than 50 Myr, and deep genetic divergence was confirmed by nuclear sequence data. Among six sister-group comparisons of osteoglossomorphs,
Pantodon
exhibits the slowest rate of morphological divergence despite a level of genetic differentiation comparable to both species-rich (e.g. Mormyridae) and species-poor (e.g. Osteoglossidae) families. Morphological stasis in these two allopatric lineages of
Pantodon
offers a living vertebrate model for investigating phenotypic stability over millions of generations in the face of profound fluctuations in environmental conditions.
Modelling the ecological niche from functional traits
Authors: Kearney Michael , Simpson Stephen J. , Raubenheimer David , Helmuth Brian
Published: September 2010

The niche concept is central to ecology but is often depicted descriptively through observing associations between organisms and habitats. Here, we argue for the importance of mechanistically modelling niches based on functional traits of organisms and explore the possibilities for achieving this through the integration of three theoretical frameworks: biophysical ecology (BE), the geometric framework for nutrition (GF) and dynamic energy budget (DEB) models. These three frameworks are fundamentally based on the conservation laws of thermodynamics, describing energy and mass balance at the level of the individual and capturing the prodigious predictive power of the concepts of ‘homeostasis’ and ‘evolutionary fitness’. BE and the GF provide mechanistic multi-dimensional depictions of climatic and nutritional niches, respectively, providing a foundation for linking organismal traits (morphology, physiology, behaviour) with habitat characteristics. In turn, they provide driving inputs and cost functions for mass/energy allocation within the individual as determined by DEB models. We show how integration of the three frameworks permits calculation of activity constraints, vital rates (survival, development, growth, reproduction) and ultimately population growth rates and species distributions. When integrated with contemporary niche theory, functional trait niche models hold great promise for tackling major questions in ecology and evolutionary biology.
Extrapolating toxic effects on individuals to the population level: the role of dynamic energy budgets
Authors: Jager Tjalling , Klok Chris
Published: September 2010

The interest of environmental management is in the long-term health of populations and ecosystems. However, toxicity is usually assessed in short-term experiments with individuals. Modelling based on dynamic energy budget (DEB) theory aids the extraction of mechanistic information from the data, which in turn supports educated extrapolation to the population level. To illustrate the use of DEB models in this extrapolation, we analyse a dataset for life cycle toxicity of copper in the earthwormDendrobaena octaedra. We compare four approaches for the analysis of the toxicity data: no model, a simple DEB model without reserves and maturation (the Kooijman–Metz formulation), a more complex one with static reserves and simplified maturation (as used in the DEBtox software) and a full-scale DEB model (DEB3) with explicit calculation of reserves and maturation. For the population prediction, we compare two simple demographic approaches (discrete time matrix model and continuous time Euler–Lotka equation). In our case, the difference between DEB approaches and population models turned out to be small. However, differences between DEB models increased when extrapolating to more field-relevant conditions. The DEB3 model allows for a completely consistent assessment of toxic effects and therefore greater confidence in extrapolating, but poses greater demands on the available data.
How far details are important in ecosystem modelling: the case of multi-limiting nutrients in phytoplankton–zooplankton interactions
Authors: Poggiale J.-C. , Baklouti M. , Queguiner B. , Kooijman S. A. L. M.
Published: September 2010

We try to answer the question of to what extent details in nutrient uptake and phytoplankton physiology matter for population and community dynamics. To this end, we study how two nutrients interact in limiting phytoplankton growth. A popular formulation uses a product-rule for nutrient uptake, which we compare with that on the basis of synthesizing units. We first fit different nutrient uptake models to a dataset and conclude that the quantitative differences between the models are small. Then we study the sensitivity of phytoplankton growth and zooplankton–phytoplankton interactions (ZPi) models to uptake formulations. Two population models are compared; they are based on different assumptions on the relation between nutrient uptake and phytoplankton growth. We find that the population and community models are sensitive to uptake formulations. According to the uptake formulation used in the ZPi models, qualitative differences can be observed. Indeed, although two models based on functions with similar shapes have close equilibria, these can differ in stability properties. Since stability involves the derivatives of formulas, even if two formulas provide close values, large numerical differences in the stability criterion may occur after derivation. We conclude that mechanistic details can be of importance for community modelling.
Dynamic energy budget theory and population ecology: lessons from
Daphnia
Authors: Nisbet Roger M. , McCauley Edward , Johnson Leah R.
Published: September 2010

Dynamic energy budget (DEB) theory offers a perspective on population ecology whose starting point is energy utilization by, and homeostasis within, individual organisms. It is natural to ask what it adds to the existing large body of individual-based ecological theory. We approach this question pragmatically—through detailed study of the individual physiology and population dynamics of the zooplankter
Daphnia
and its algal food. Standard DEB theory uses several state variables to characterize the state of an individual organism, thereby making the transition to population dynamics technically challenging, while ecologists demand maximally simple models that can be used in multi-scale modelling. We demonstrate that simpler representations of individual bioenergetics with a single state variable (size), and two life stages (juveniles and adults), contain sufficient detail on mass and energy budgets to yield good fits to data on growth, maturation and reproduction of individual
Daphnia
in response to food availability. The same simple representations of bioenergetics describe some features of
Daphnia
mortality, including enhanced mortality at low food that is not explicitly incorporated in the standard DEB model. Size-structured, population models incorporating this additional mortality component resolve some long-standing questions on stability and population cycles in
Daphnia
. We conclude that a bioenergetic model serving solely as a ‘regression’ connecting organismal performance to the history of its environment can rest on simpler representations than those of standard DEB. But there are associated costs with such pragmatism, notably loss of connection to theory describing interspecific variation in physiological rates. The latter is an important issue, as the type of detailed study reported here can only be performed for a handful of species.
Instrumental developments for anomalous small-angle X-ray scattering from soft matter systems
Authors: Sztucki Michael , Di Cola Emanuela , Narayanan Theyencheri
Published: September 2010

An optimized instrument for anomalous small-angle X-ray scattering from charged soft matter is described. The experimental setup takes special care for single-photon detection sensitivity, high energy resolution of the monochromator,in situcalibration of intensity and energy, and the avoidance of radiation damage. Measured intensities are normalized to an absolute scale online, which can be further decomposed to resonant and non-resonant contributions. The performance of the instrument is demonstrated by an example involving cationic surfactant micelles with bromide counter-ions. The counter-ion profile around the micelle is deduced from the analysis of anomalous scattering near theK-absorption edge of bromine. Two different approaches yield similar results for the radial profile of the counter-ions, showing strong condensation of the counter-ions on the micellar surface, in agreement with the inference from electrochemical methods.
Estimation of errors in diffraction data measured by CCD area detectors
Authors: Waterman David , Evans Gwyndaf
Published: September 2010

Current methods for diffraction-spot integration from CCD area detectors typically underestimate the errors in the measured intensities. In an attempt to understand fully and identify correctly the sources of all contributions to these errors, a simulation of a CCD-based area-detector module has been produced to address the problem of correct handling of data from such detectors. Using this simulation, it has been shown how, and by how much, measurement errors are underestimated. A model of the detector statistics is presented and an adapted summation integration routine that takes this into account is shown to result in more realistic error estimates. In addition, the effect of correlations between pixels on two-dimensional profile fitting is demonstrated and the problems surrounding improvements to profile-fitting algorithms are discussed. In practice, this requires knowledge of the expected correlation between pixels in the image.
Observation of unusual temperature-dependent stripes in LiTaO3and LiTaxNb1−xO3crystals with near-zero birefringence
Authors: Glazer A. M. , Zhang Nan , Bartasyte Ausrine , Keeble D. S. , Huband S. , Thomas P. A.
Published: September 2010

A birefringence imaging microscopy study of LiTaO3and some mixed LiTaxNb1−xO3crystals is reported. The initially congruent LiTaO3crystals have been subject to vapour transport equilibration in order to increase the Li content and at the same time to reduce the optical birefringence close to zero at room temperature. In both types of crystal, the presence of unusual periodic self-organized stripes, existing over large distances, has been observed, which correlate with the well documented cleavage and twin planes in this material. Furthermore, the stripes become narrower as the temperature is changed away from the zero-birefringence temperature, but become temperature-independent above the ferroelectric–paraelectric phase-transition temperature.
Personal, family and social functioning among older couples concordant and discordant for high‐risk alcohol consumption
Authors: Moos Rudolf H. , Schutte Kathleen K. , Brennan Penny L. , Moos Bernice S.
Published: September 2010

Aims  This study compares the personal, family and social functioning of older husbands and wives concordant or discordant for high‐risk alcohol consumption and identifies predictors of changes in concordance and high‐risk consumption.

Design, Participants, Measurements  Three groups of couples were identified at baseline and followed 10 years later: (i) concordant couples in which husbands and wives engaged in low‐risk alcohol consumption (n = 54); (ii) concordant couples in which husbands and wives engaged in high‐risk alcohol consumption (n = 38); and (iii) discordant couples in which one partner engaged in high‐risk alcohol consumption and the other partner did not (n = 75). At each follow‐up, husbands and wives completed an inventory that assessed their personal, family and social functioning.

Findings  Compared to the low‐risk concordant group, husbands and wives in the high‐risk concordant group were more likely to rely on tension‐reduction coping, reported more friend approval of drinking, and were less involved in religious activities; however, they did not differ in the quality of the spousal relationship. The frequency of alcohol consumption declined among husbands in discordant couples, but not among husbands in concordant couples. Predictors of high‐risk drinking included tension‐reduction coping, friend approval of drinking and, for husbands, their wives' level of drinking.

Conclusions  High‐risk and discordant alcohol consumption do not seem to be linked to decrements in family functioning among older couples in long‐term stable marriages. The predictors of heavy alcohol consumption among older husbands and wives identify points of intervention that may help to reduce their high‐risk drinking.
White international transracial adoptive mothers' reflections on race
Authors: Crolley‐Simic Josie , Vonk M. Elizabeth
Published: September 2010

Through the use of qualitative data analysis of in‐depth interviews with eight white international transracial adoptive mothers, four properties emerged that describe these mothers' racial views. These properties varied in the degree that they integrated perspectives different from the white dominant culture. The mothers did not experience significant changes in their perspective on race subsequent to adoption. This paper includes a discussion of white racial identity and implications for social work practice with transracially adoptive parents.
Toxic levels of metals in Ferralsols under natural vegetation and crops in New Caledonia
Authors: Becquer T. , Quantin C. , Boudot J. P.
Published: September 2010

The chemistry of soil solutions and the potential toxicity of trace metals (Co, Cr, Cu, Ni and Mn) were investigated on soils formed on ultramafic rocks. Soil solutions were collected along a soil toposequence under natural vegetation and under a cropped field. In the latter, metal speciation and species activity were computed with the WHAM 6 model. Total element concentrations varied with the soil topographic position. Upslope, in well‐drained soils, they were relatively small with mean concentrations of <0.2 µmol l−1 for Co and Cr and <2 µmol l−1 for Ni and Mn. Downslope, in temporarily waterlogged soils, concentrations reached 37 (Mn), 5.6 (Ni), 1.9 (Co) and 0.1 (Cr) µmol l−1. Under crops, Ni, Mn and Co concentrations were similar to those under natural vegetation, but Cr concentration averaged 5 µmol l−1. Cu concentration was close to 1 µmol l−1. Free‐ion species amounted to 53–71% of all species for Co, Ni and Mn but only 5% for Cu. Cr was almost entirely in the Cr(VI) form (CrO, HCrO. The free‐metal‐ion activities were in the range 26–81% of the corresponding free‐metal‐ion concentration. Comparing our data with levels that are toxic to crops, Ni and Cr are potentially toxic in the well‐drained and the poorly‐drained soils. In the latter, Co and Mn are also potentially toxic. Both the large concentration of metals and the chemical species in which they occur in solution could limit the use of the land for agricultural purpose.
Dynamics of long‐lived foundation species: the history ofQuercusin southern Scandinavia
Authors: Lindbladh Matts , Foster David R.
Published: September 2010

1. The long‐term history ofQuercusin southern Scandinavia has received little attention despite its important role in modern conservation. In this study the 4000‐year dynamics ofQuercus, its habitat and other important taxa were analysed with pollen data from 25 small hollows and 6 regional sites across southern Scandinavia. The aim was to provide a context for understanding the species’ current status and managing its future dynamics.

2. The results indicate thatQuercusis much less abundant today than at any time during the previous 4000 years and corroborate the rapid decline reported in 18th‐ and 19th‐century historical records. Modern pollen percentages are 45–60% of 17th‐century values and only 20–35% of the maximum values reached in the 3rd century.

3. A strong positive correlation exists between the abundance ofQuercusand the abundance ofTilia, CorylusandAlnus, which also experienced a steady decline across the region in the last two millennia. Climate change is the broad‐scale driver of the observed dynamics, but human activity introduced considerable variation in the regional and temporal details of these changes. In the hemiboreal northern part of the study area the decline ofQuercusappears to be controlled largely by competition with other tree species (especiallyPinusandPicea), mediated by harvesting. In the temperate south partQuercusforests decreased through deforestation for agriculture.

4. Multivariate analyses indicate that although substantial phytogeographical variation has existed through past millennia the regional vegetation is more homogeneous today than in earlier periods.

5. Synthesis. The long‐term decline and recent rapid reductions inQuercuspopulations throughout southern Scandinavia are striking and indisputable. From the perspective of both the populations ofQuercusand its associated species of insects and epiphytes, the recent rate of decline is extremely rapid. Given the former abundance, longevity and capacity for persistence ofQuercus, current populations ofQuercusand its associated species appear to represent biological legacies in the midst of protracted decline. Based on these results, a reasonable conservation goal is to restore the abundance and distribution ofQuercusto levels that preceded the drastic decline in the 18th and 19th centuries.
Adaptation of redband trout in desert and montane environments
Authors: NARUM SHAWN R. , CAMPBELL NATHAN R. , KOZFKAY CHRISTINE C. , MEYER KEVIN A.
Published: September 2010

Natural populations that evolve under extreme climates are likely to diverge because of selection in local environments. To explore whether local adaptation has occurred in redband trout (Oncorhynchus mykiss gairdneri) occupying differing climate regimes, we used a limited genome scan approach to test for candidate markers under selection in populations occurring in desert and montane streams. An environmental approach to identifying outlier loci, spatial analysis method and linear regression of minor allele frequency with environmental variables revealed six candidate markers (P < 0.01). Putatively neutral markers identified high genetic differentiation among desert populations relative to montane sites, likely due to intermittent flows in desert streams. Additionally, populations exhibited a highly significant pattern of isolation by temperature (P < 0.0001) and those adapted to the same environment had similar allele frequencies across candidate markers, indicating selection for differing climates. These results imply that many genes are involved in the adaptation of redband trout to differing environments, and selection acts to reinforce localization. The potential to predict genetic adaptability of individuals and populations to changing environmental conditions may have profound implications for species that face extensive anthropogenic disturbances.
Extremely low genetic variability and highly structured local populations of Arabidopsis thaliana at higher latitudes
Authors: LEWANDOWSKA‐SABAT A. M. , FJELLHEIM S. , ROGNLI O. A.
Published: September 2010

The genetic diversity and population structure of Arabidopsis thaliana populations from Norway were studied and compared to a worldwide sample of A. thaliana to investigate the demographic history and elucidate possible colonization routes of populations at the northernmost species limit. We genotyped 282 individuals from 31 local populations using 149 single nucleotide polymorphism markers. A high level of population subdivision (FST = 0.85 ± 0.007) was found indicating that A. thaliana is highly structured at the regional level. Significant relationships between genetic and geographical distances were found, suggesting an isolation by distance mode of evolution. Genetic diversity was much lower, and the level of linkage disequilibrium was higher in populations from the north (65–68°N) compared to populations from the south (59–62°N); this is consistent with a northward expansion pattern. A neighbour‐joining tree showed that populations from northern Norway form a separate cluster, while the remaining populations are distributed over a few minor clusters. Minimal gene flow seems to have occurred between populations in different regions, especially between the geographically distant northern and southern populations. Our data suggest that northern populations represent a homogenous group that may have been established from a few founders during northward expansions, while populations in the central part of Norway constitute an admixed group established by founders of different origins, most probably as a result of human‐mediated gene flow. Moreover, Norwegian populations appeared to be homogenous and isolated compared to a worldwide sample of A. thaliana, but they are still grouped with Swedish populations, which may indicate common colonization histories.
Increased gene sampling yields robust support for higher‐level clades within Bombycoidea (Lepidoptera)
Authors: ZWICK ANDREAS , REGIER JEROME C. , MITTER CHARLES , CUMMINGS MICHAEL P.
Published: September 2010

This study has as its primary aim the robust resolution of higher‐level relationships within the lepidopteran superfamily Bombycoidea. Our study builds on an earlier analysis of five genes (∼6.6 kbp) sequenced for 50 taxa from Bombycoidea and its sister group Lasiocampidae, plus representatives of other macrolepidoteran superfamilies. The earlier study failed to yield strong support for the monophyly of and basal splits within Bombycoidea, among others. Therefore, in an effort to increase support specifically for higher‐level nodes, we generated 11.7 kbp of additional data from 20 genes for 24 of 50 bombycoid and lasiocampid taxa. The data from the genes are all derived from protein‐coding nuclear genes previously used to resolve other lepidopteran relationships. With these additional data, all but a few higher‐level nodes are strongly supported. Given our decision to minimize project costs by augmenting genes for only 24 of the 50 taxa, we explored whether the resulting pattern of missing data in the combined‐gene matrix introduced a nonphylogenetic bias, a possibility reported by others. This was achieved by comparing node support values (i.e. nonparametric bootstrap values) based on likelihood and parsimony analyses of three datasets that differ in their number of taxa and level of missing data: 50 taxa/5 genes (dataset A), 50 taxa/25 genes (dataset B) and 24 taxa/25 genes (dataset C). Whereas datasets B and C provided similar results for common nodes, both frequently yielded higher node support relative to dataset A, arguing that: (i) more data yield increased node support and (ii) partial gene augmentation does not introduce an obvious nonphylogenetic bias. A comparison of single‐gene bootstrap analyses identified four nodes for which one or two of the 25 genes provided modest to strong support for a grouping not recovered by the combined‐gene result. As a summary proposal, two of these four groupings (one each within Bombycoidea and Lasiocampidae) were deemed sufficiently problematic to regard them as unresolved trichotomies. Since the alternative groupings were always highly localized on the tree, we did not judge a combined‐gene analysis to present a problem outside those regions. Based on our robustly resolved results, we have revised the classification of Bombycoidea: the family Bombycidae is restricted to its nominate subfamily, and its tribe Epiini is elevated to subfamily rank (Epiinae stat.rev.), whereas the bombycid subfamily Phiditiinae is reinstated as a separate family (Phiditiidae stat.rev.). The bombycid subfamilies Oberthueriinae Kuznetzov & Stekolnikov, 1985, syn.nov. and Prismostictinae Forbes, 1955, syn.nov., and the family Mirinidae Kozlov, 1985, syn.nov. are established as subjective junior synonyms of Endromidae Boisduval, 1828. The family Anthelidae (Lasiocampoidea) is reincluded in the superfamily Bombycoidea.
Suppressive effects of intravenous immunoglobulin (IVIG) on human umbilical cord blood immune cells
Authors: Qian Jihong , Zhu Jianxing , Wang Meihong , Wu Shengmei , Chen Tongxin
Published: September 2010

To cite this article: Qian J, Zhu J, Wang M, Wu S, Chen T. Suppressive effects of intravenous immunoglobulin (IVIG) on human umbilical cord blood immune cells. Pediatr Allergy Immunol 2011; 22: 211–220.

We investigated in vitro immunomodulatory effects of intravenous immunoglobulin (IVIG) on cord blood mononuclear cells (CBMNC), macrophages, dendritic cells and CD3+ T cells were isolated from umbilical venous blood. Cell proliferation used 3H‐TdR incorporation, culture supernatants were assayed for cytokines using ELISA, and surface marker expressions were determined by flow cytometry. IVIG suppressed CBMNCs and CD3+T‐cells proliferation, secretions of IL‐10, INF‐γ and TGF‐β1, but not IL‐4, and PHA‐induced expressions of surface molecules (CD25, CD45RA and CD45RO), with more pronounced effects for CBMNCs. IVIG decreased cord blood (CB) macrophage phagocytosis and CD14, HLA‐DR and CD86 expressions. IVIG increased CD14 expression and decreased MCH II expression for differentiation‐stage CB dendritic cells (DCs) and increased CD14 expression and decreased CD80 and CD83 expressions of mature DCs, suggesting that IVIG intervention inhibited DC differentiation and maturation. In addition to T cells, IVIG immunomodulatory effects on CBMNCs involve a variety of cells and molecules. CB macrophages and CBMNC‐DCs are targets of IVIG.
Problematic severe asthma: A proposed approach to identifying children who are severely resistant to therapy
Authors: Konradsen Jon R. , Nordlund Björn , Lidegran Marika , Pedroletti Christophe , Grönlund Hans , van Hage Marianne , Dahlen Barbro , Hedlin Gunilla ,   In Cooperation with the Swedish network of Pediatric Allergists, Severe Asthma Network
Published: September 2010

To cite this article: Konradsen JR, Nordlund B, Lidegran M, Pedroletti C, Gro¨nlund H, van Hage M, Dahlen B, Hedlin G and In Cooperation with the Swedish network of Pediatric Allergists, Severe Asthma Network. Problematic severe asthma: A proposed approach to identifying children who are severely resistant to therapy. Pediatric Allergy Immunology 2011: 22: 9–18.

Children with problematic severe asthma (PA) are either difficult to treat because of the presence of aggravating factors or else severely resistant to therapy. We investigated a cohort of school‐aged children with PA and compared these children to age‐matched peers with controlled persistent asthma (CA). The aims were to characterize features of children suffering from PA and identify children who were severely resistant to therapy. In this cross‐sectional, multicenter comparison of children with different manifestations of persistent asthma, PA was defined as insufficient asthma control despite level 4 treatment, according to GINA. The protocol included questionnaires, spirometry, methacholine provocation, measurement of fraction of nitric oxide in exhaled (FENO) and nasal air, blood sampling for inflammatory biomarkers and atopy, and computerized tomography of sinuses and lungs (in the PA group only). Of the 54 children with PA, 61% had therapy‐resistant asthma, with the remaining being difficult to treat because of identified aggravating factors. Children with PA more often had parents with asthma (p = 0.003), came from families with a lower socioeconomic status (p = 0.01), were less physically active (p = 0.04), and had more comorbidity with rhinoconjunctivitis (p = 0.01) than did the 39 children with CA. The former also exhibited lower FEV1 values (p = 0.02) and increased bronchial hyper‐responsiveness (p = 0.01), but there were no differences in atopy (p = 0.81) or FENO (p = 0.16). A non‐invasive protocol, involving a standardized and detailed clinical characterization, revealed distinguishing features of children with PA and enabled the identification of children with therapy‐resistant asthma.
Preparing for transition? The allocation of oral medication regimen tasks in adolescents with renal transplants
Authors: Pai Ahna L. H. , Ingerski Lisa M. , Perazzo Lauren , Ramey Christina , Bonner Margaret , Goebel Jens
Published: September 2010

Pai ALH, Ingerski LM, Perazzo L, Ramey C, Bonner M, Goebel J. Preparing for transition? The allocation of oral medication regimen tasks in adolescents with renal transplants. Pediatr Transplantation 2011: 15:9–16. © 2010 John Wiley & Sons A/S.

Abstract: A mixed‐methods design was utilized to examine strategies that families use to manage the post‐transplant oral medication regimen of adolescents with renal transplants. Seventeen adolescents and their caregivers were administered structured interviews assessing the tasks that families identified as comprising the oral medication regimen, how tasks were allocated across family members and how the dyad decided on the allocation of tasks. Adherence was assessed via electronic pill bottles and calculated by dividing the number of doses taken by those prescribed. Patients and their caregivers identified the following tasks as part of the oral medication regimen: filling the pillbox (71%), calling for refills (65%) and verifying that the pillbox is filled correctly (47%). Adult caregivers were primarily responsible for managing the medication regimen for the majority of adolescents (70%). Secondary analyses revealed that the number of oral medication regimen tasks identified by the dyad was significantly associated with patient adherence. Our findings highlight the need to bolster efforts to develop methods to quantitatively assess and promote self‐management skills among adolescents with renal transplants.
Is endoscopic surveillance for non‐dysplastic Barrett's esophagus cost‐effective? Review of economic evaluations
Authors: Hirst Nicholas G , Gordon Louisa G , Whiteman David C , Watson David I , Barendregt Jan J
Published: September 2010

Background and Aim: Several health economic evaluations have explored the cost‐effectiveness of endoscopic surveillance for patients with non‐dysplastic Barrett's esophagus, with conflicting results. By comparing results across studies and highlighting key methodological and data limitations a platform for future, more rigorous analyses, can be developed.

Methods: A systematic literature review was undertaken of studies evaluating cost‐effectiveness of surveillance for non‐dysplastic Barrett's esophagus. Articles were included if they assessed both cost and health outcomes for surveillance versus no surveillance. A descriptive review was undertaken and the quality of the studies appraised against best‐practice recommendations for economic evaluations and modeling studies.

Results: Seven publications met the inclusion criteria. All used decision‐analytic Markov models. Half of the evaluations found surveillance was not cost‐effective. At best, surveillance produced improved outcomes at a cost of US$16 640 per quality‐adjusted life‐year, and at worst it did more harm than good and at a greater cost. The quality of the evaluations and generalizability to the Asia‐Pacific region was diminished as a result of inadequate or inconsistent evidence supporting parameter estimates, such as quality of life, endoscopic sensitivity and specificity and cancer recurrence rates.

Conclusions: Unless newly emerging technologies improve the quality‐adjusted survival benefit conferred by endoscopic surveillance, this strategy is unlikely to be cost‐effective. Obsolete assumptions and incomplete analyses reduce the quality of published evaluations. For these reasons new evaluations are required that encompass the growing evidence base for new technologies, such as new endoscopic therapies for high‐grade dysplasia and intramucosal cancer.