bluuebunny/crossref_metadata_2025_split huggingface dataset:
Endocrine effects of polycyclic musks: do we smell a rat?
Authors: Van Der Burg Bart , Schreurs Richard , Van Der Linden Sander , Seinen Willem , Brouwer Abraham , Sonneveld Edwin 
Published: October 2007

SummarySynthetic polycyclic musks are used extensively as fragrances and are released ubiquitously in our environment, particularly water. We have demonstrated that these compounds display very weak oestrogenic activity in vitro, although no obvious oestrogenic activity was found in young rats or zebrafish. We demonstrated, however, that the oestrogenic effect of these compounds is cell‐ and oestrogen receptor‐type specific, raising the possibility that the in vivo models may have underestimated some effects. In addition, polycyclic musks were found to possess antioestrogenic (ERβ‐selective), antiandrogenic and antiprogestagenic activity. As recent research clearly demonstrates the possibility of endocrine disrupting environmental compounds to act in concert, more research to these combined effects is important. We have developed efficient methods to measure such combined bioactivities in a range of matrices using human cell‐based reporter gene assays. So far, we found agonistic, rather than antagonistic, effects in water samples, suggesting a predominance of agonistic compounds in such samples.
Ecological corridors, connecting science and politics: the case of the Green River in the Netherlands
Authors: Van Der Windt Henny J. , Swart J. A. A. 
Published: October 2007

Summary

During recent decades, the ecological corridor has become a popular concept among ecologists, politicians and nature conservationists. However, it has been criticized from a scientific point of view. In this paper we question why this concept has been accepted so readily in policy and practice.
We present a conceptual framework to analyse the rise of the concept, especially in the Netherlands. We have studied the Dutch literature from the period 1980–2005, including the main ecological journal Landschap (Landscape), policy documents and reports from the leading Dutch policy‐orientated ecology research centre.
Many actors, including politicians, stakeholders and scientists, were involved in the development of the ecological corridor and the related National Ecological Network on the national and regional levels. The involvement of these actors changed the character of the concept into the multifunctional ‘robust corridor’.
The ecological corridor was probably so influential because its vague and flexible character facilitated the coming together of various stakeholders and scientists. It also functions as a metaphor, applicable to well‐known entities such as construction and transport. Finally, scientists from the policy‐orientated research centre were able to link the concept to fundamental science, policy and practice. In some stages of the policy‐defining process, however, conflicts arose between the proponents of scientific soundness and those of social robustness that reduced the role of scientists.
Synthesis and applications. To make ecological concepts both scientifically sound and socially robust, several changes must take place in current interactions between ecology and society. First, during concept development it requires the existence of extensive, largely interactive peer groups with clearly defined relationships between scientists and non‐scientists. Secondly, the concepts should be flexible and relatable to relevant knowledge, insights, values and practices. Thirdly, several feedback loops between science and non‐science should be set up during the various stages of concept development and implementation.
Does forest structure affect reproduction of northern goshawks in ponderosa pine forests?
Authors: Beier Paul , Rogan Erik C , Ingraldi Michael F , Rosenstock Steven S 
Published: October 2007

SummaryMany management prescriptions are based on ecological hypotheses; evaluating empirical support for these hypotheses can improve management. There has been considerable dispute about the potential response of the northern goshawk to three management‐driven forest structures in ponderosa pine forests of the south‐western United States: (i) the structure recommended by US Forest Service's goshawk guidelines, designed to increase the abundance of 14 goshawk prey species and thus benefit goshawks; (ii) preferred foraging habitat as suggested by empirical evidence that goshawks forage selectively in areas with abundant large trees and dense canopy closure, rather than areas of highest prey abundance; and (iii) presettlement (i.e. prior to Euro‐American settlement) structure characterized by clumps of large trees, canopy closure < 40% and dense herbaceous understorey, which could have negative effects on goshawks.To evaluate empirical support for hypotheses that goshawk reproduction is affected by each of these three forest structures, we measured forest structure in a 1215‐ha nest‐centred circular area in each of 13 goshawk breeding areas on the Apache–Sitgreaves National Forest, Arizona. The breeding areas were selected to span the full range of productivity (fledglings per year monitored) over the previous 9‐year period.Forest structure had a moderate effect on goshawk productivity (r2 ≤ 0·46). Contrary to expectation, goshawk productivity decreased with increasing similarity to the goshawk guidelines.Goshawk reproduction was not correlated with resemblance of the breeding area to preferred foraging habitat or resemblance to presettlement forest conditions.Synthesis and applications. Because the goshawk guidelines may not improve goshawk reproduction, the Forest Service should reconsider its decision to apply the guidelines to most forested lands in Arizona and New Mexico. Managers should evaluate empirical support routinely for the major ecological hypotheses that underlie forest prescriptions.
Hybrid origin of Baltic salmon‐specific parasite Gyrodactylus salaris: a model for speciation by host switch for hemiclonal organisms
Authors: KUUSELA JUSSI , ZIĘTARA MAREK S. , LUMME J. 
Published: October 2007

AbstractHost switching explains the high species number of ectoparasitic, viviparous, mainly parthenogenetic but potentially hermaphroditic flatworms of the genus Gyrodactylus. The starlike mitochondrial phylogeny of Gyrodactylus salaris suggested parallel divergence of several clades on grayling (also named as Gyrodactylus thymalli) and an embedded sister clade on Baltic salmon. The hypothesis that the parasite switched from grayling to salmon during the glacial diaspora was tested using a 493‐bp nuclear DNA marker ADNAM1. The parasites on salmon in lakes Onega and Ladoga were heterozygous for divergent ADNAM1 alleles WS1 and BS1, found as nearly fixed in grayling parasites in the White Sea and Baltic Sea basins, respectively. In the Baltic salmon‐specific mtDNA clade, the WS/BS heterozygosity was maintained in 23 out of the 24 local clones. The permanently heterozygous clade was endemic in the Baltic Sea basin, and it had accumulated variation in mtDNA (31 variable sites on 1600 bp) and in the alleles of the nuclear locus (two point mutations and three nucleotide conversions along 493 bp). Mendelian shuffling of the nuclear alleles between the local clones indicated rare sex within the clade, but the WS/BS heterozygosity was lost in only one salmon hatchery clone, which was heterozygous WS1/WS3. The Baltic salmon‐specific G. salaris lineage was monophyletic, descending from a single historical hybridization and consequential host switch, frozen by permanent heterozygosity. A possible time for the hybridization of grayling parasite strains from the White Sea and Baltic Sea basins was during the Eemian interglacial 132 000 years bp. Strains having a separate divergent mtDNA observed on farmed rainbow trout, and on salmon in Russian lake Kuito were suggested to be clones derived from secondary and tertiary recombination events.
Candidate loci reveal genetic differentiation between temporally divergent migratory runs of Chinook salmon (Oncorhynchus tshawytscha)
Authors: O'MALLEY KATHLEEN G. , CAMARA MARK D. , BANKS MICHAEL A. 
Published: October 2007

AbstractLocal adaptation is a dynamic process driven by selection that can vary both in space and time. One important temporal adaptation for migratory animals is the time at which individuals return to breeding sites. Chinook salmon (Oncorhynchus tshawytscha) are excellent subjects for studying the genetic basis of temporal adaptation because their high seasonal homing fidelity promotes reproductive isolation leading to the formation of local populations across diverse environments. We tested for adaptive genetic differentiation between seasonal runs of Chinook salmon using two candidate loci; the circadian rhythm gene,OtsClock1b,andOts515NWFSC, a microsatellite locus showing sequence identity to three salmonid genes central to reproductive development. We found significant evidence for two genetically distinct migratory runs in the Feather River, California (OtsClock1b: FST = 0.042,P = 0.02;Ots515NWFSC: FST = 0.058,P = 0.003). In contrast, the fall and threatened spring runs are genetically homogenous based on neutral microsatellite data (FST = –0.0002). Similarly, two temporally divergent migratory runs of Chinook salmon from New Zealand are genetically differentiated based on polymorphisms in the candidate loci (OtsClock1b: FST = 0.083,P‐value = 0.001;Ots515NWFSC: FST = 0.095,P‐value = 0.000). We used an individual‐based assignment method to confirm that these recently diverged populations originated from a single source in California. Tests for selective neutrality indicate thatOtsClock1bandOts515NWFSCexhibit substantial departures from neutral expectations in both systems. The largeFSTestimates could therefore be the result of directional selection. Evidence presented here suggests thatOtsClock1bandOts515NWFSCmay influence migration and spawning timing of Chinook salmon in these river systems.
Polygynandry, extra‐group paternity and multiple‐paternity litters in European badger (Meles meles) social groups
Authors: DUGDALE HANNAH L. , MACDONALD DAVID W. , POPE LISA C. , BURKE TERRY 
Published: October 2007

AbstractThe costs and benefits of natal philopatry are central to the formation and maintenance of social groups. Badger groups, thought to form passively according to the resource dispersion hypothesis (RDH), are maintained through natal philopatry and delayed dispersal; however, there is minimal evidence for the functional benefits of such grouping. We assigned parentage to 630 badger cubs from a high‐density population in Wytham Woods, Oxford, born between 1988 and 2005. Our methodological approach was different to previous studies; we used 22 microsatellite loci to assign parent pairs, which in combination with sibship inference provided a high parentage assignment rate. We assigned both parents to 331 cubs at ≥ 95% confidence, revealing a polygynandrous mating system with up to five mothers and five fathers within a social group. We estimated that only 27% of adult males and 31% of adult females bred each year, suggesting a cost to group living for both sexes. Any strong motivation or selection to disperse, however, may be reduced because just under half of the paternities were gained by extra‐group males, mainly from neighbouring groups, with males displaying a mixture of paternity strategies. We provide the strongest evidence to date for multiple‐paternity litters, and for the first time show that within‐group and extra‐group males can sire cubs in the same litter. We investigate the factors that may play a role in determining the degree of delayed dispersal and conclude that the ecological constraints hypothesis, benefits of philopatry hypothesis, and life history hypothesis may all play a part, as proposed by the broad constraints hypothesis.
Differential gene flow of mitochondrial and nuclear DNA markers among chromosomal races of Australian morabine grasshoppers (Vandiemenella, viatica species group)
Authors: KAWAKAMI T. , BUTLIN R. K. , ADAMS M. , SAINT K. M. , PAULL D. J. , COOPER S. J. B. 
Published: October 2007

AbstractRecent theoretical developments have led to a renewed interest in the potential role of chromosomal rearrangements in speciation. Australian morabine grasshoppers (genus Vandiemenella, viatica species group) provide an excellent study system to test this potential role of chromosomal rearrangements because they show extensive chromosomal variation and formed the basis of a classic chromosomal speciation model. There are three chromosomal races, viatica19, viatica17, and P24(XY), on Kangaroo Island, South Australia, forming five parapatric populations with four putative contact zones among them. We investigate the extent to which chromosomal variation among these populations may be associated with barriers to gene flow. Population genetic and phylogeographical analyses using 15 variable allozyme loci and the elongation factor‐1α (EF‐1α) gene indicate that the three races represent genetically distinct taxa. In contrast, analyses of the mitochondrial cytochrome c oxidase subunit I (COI) gene show the presence of three distinctive and geographically localized groups that do not correspond with the distribution of the chromosomal races. These discordant population genetic patterns are likely to result from introgressive hybridization between the chromosomal races and range expansions/contractions. Overall, these results suggest that reduction of nuclear gene flow may be associated with chromosomal variation, or underlying genetic variation linked with chromosomal variation, whereas mitochondrial gene flow appears to be independent of this variation in these morabine grasshoppers. The identification of an intact contact zone between P24(XY) and viatica17 offers considerable potential for further investigation of molecular mechanisms that maintain distinct nuclear genomes among the chromosomal races.
FtsK and SpoIIIE: the tale of the conserved tails
Authors: Barre François‐Xavier 
Published: October 2007

SummaryDuring Bacillus subtilis sporulation, the SpoIIIE DNA translocase moves a trapped chromosome across the sporulation septum into the forespore. The preferential assembly of SpoIIIE complexes in the mother cell provided the idea that SpoIIIE functioned as a DNA exporter, which ensured translocation orientation. In this issue of Molecular Microbiology, Becker and Pogliano reinvestigate the molecular mechanisms that orient the activity of SpoIIIE. Their findings indicate that SpoIIIE reads the polarity of DNA like its Escherichia coli homologue, FtsK.
Rhodolith‐bearing limestones as transgressive marker beds: fossil and modern examples from North Island, New Zealand
Authors: NALIN RONALD , NELSON CAMPBELL S. , BASSO DANIELA , MASSARI FRANCESCO 
Published: October 2007

AbstractRhodoliths are nodular structures composed mainly of the superimposed thalli of calcareous red algae. Because their development is controlled by an array of ecological parameters, rhodoliths are a valuable source of palaeoenvironmental information. However, despite their common use in palaeoecological reconstructions, the stratigraphic significance of rhodolith accumulations seldom has been addressed in detail. In a study of Cenozoic rhodolith‐bearing deposits from the North Island of New Zealand, rhodolithic units, usually of limited lateral extent, typically occur above major unconformities at the base of deepening upwards successions. Two types of transgressive rhodolith‐bearing deposits may be distinguished on the basis of texture and rhodolith internal structure: (i) type A deposits are clast‐supported rhodolithic rudstones containing abundant pebbles and cobbles reworked from the substrate, and are characterized by rhodoliths with a compact concentric to columnar internal structure and a high nucleus to algal cover ratio; (ii) type B deposits are rhodolithic floatstones with a matrix usually consisting of bryozoan fragments, benthic foraminifera and echinoid fragments or terrigenous silty fine sand. The rhodoliths of type B units usually have a loose internal framework with irregular to branched crusts. The two contrasting rhodolith‐bearing units are interpreted as characteristic facies of transgressive systems tract deposits, analogous to shell concentrations formed under conditions of low net sedimentation. Type A deposits are correlated with relatively high‐energy settings and/or narrow submerged palaeotopographic lows, whereas type B deposits are interpreted as forming in lower‐energy settings. The association between transgression and development of rhodolithic facies is confirmed by observations of a modern rhodolith production site at Whangaparaoa Peninsula in North Island, where algal nodules grow above a ravinement surface cut during the Holocene sea‐level rise, and also by a review of published fossil examples, many of which show stratigraphic and compositional attributes analogous to those of the New Zealand occurrences. The review indicates that transgressive rhodolith accumulations develop more commonly in, but are not restricted to, non‐tropical settings. It is suggested that a combination of factors, such as low net sedimentary input, nature of the substrate, sea‐level rise and inherited physiography contribute to determine the relationship between rhodolith‐bearing deposits and transgressive settings.
Low temperature behaviour of natural saline fluid inclusions in saddle dolomite (Paleozoic, NW Spain)
Authors: Lapponi Fabio , Bakker Ronald J. , Bechstaedt Thilo 
Published: October 2007

AbstractThe origin of many dolomites is still a matter of debate because of many possible chemical and hydrological conditions of formation. Fluid inclusion studies have been applied in order to improve knowledge about paleofluids responsible for the precipitation of dolomite, and used to define temperatures and salinities. The combination of Raman Spectroscopy and microthermometry is tested here to improve the analytical method to identify the main ion species present in individual inclusions. Natural samples of saddle dolomite from the Cambrian Láncara Fm., Cantabrian Mountains (NW Spain), contain zoned crystals with two‐phase aqueous fluid inclusions (liquid‐rich). The most stable phase assemblage in these inclusions at −150 °C consists of ice, hydrohalite and an unknown salt hydrate. The latter melts between −47 and −41 °C, probably representing a eutectic temperature. Subsequently, ice melts in the range of −32.5 to −29 °C and, finally, hydrohalite melts between −9 and −3.5 °C. Salinities can be calculated in the fluid system H2O–NaCl with addition of another salt, either CaCl2 or MgCl2, and result in 7.5–10.6 eq. mass% NaCl and 17.0–21.0 eq. mass% CaCl2. Dependent on the rate of cooling runs, three different types of metastability may occur, i.e. the absence of hydrohalite, the unknown salt‐hydrate is not formed, and the nucleation of only ice. Salinity calculations from those melting temperatures differ substantially from equilibrium behaviour values. The unknown salt‐hydrate needs to be further specified by comparison to standard solutions. The method gives an opportunity to characterize the major compounds in complex fluid systems active during dolomitization, thus contributing to a better understanding of the ‘dolomite problem’.
Unique deformation processes involving the recrystallization of chrysotile within serpentinite: implications for aseismic slip events within subduction zones
Authors: Hirauchi Ken‐ichi , Yamaguchi Haruka 
Published: October 2007

AbstractSerpentinite bodies within the Franciscan Complex, a Mesozoic accretionary prism located in California, USA, display a unique form of deformation that involves the recrystallization of chrysotile and the formation of a block‐in‐matrix structure. The phacoidal‐shaped blocks have a preferred orientation, and result from the local replacement of serpentine minerals by chrysotile grains that are aligned parallel to ductile shear planes such as S–C foliation; ultimately, some of the rocks evolved into chrysotile schist. The relic blocks are also fragmented into multiple parts, with the spaces between fragments being infilled by recrystallized chrysotile. The low coefficient of friction of chrysotile means that this deformation process acts to suppress the frictional properties of the entire serpentinite body within the forearc mantle. This phenomenon can be attributed to the slip style that occurs in aseismic regions of subduction zones in areas shallower than the stability field of antigorite.
Migration and shortening rates in the northern Apennines, Italy: implications for seismic hazard
Authors: Basili Roberto , Barba Salvatore 
Published: October 2007

AbstractIs compression across the northern Apennine fold‐and‐thrust system (Italy) still active? To address this question, we quantified the long‐term rates of migration and shortening of the system along with the measurement errors. Our approach integrates structural geology, seismicity patterns, and statistical treatment of tectonic activity. On the basis of recently published surface and subsurface data, we found a migration rate of 8.85 ± 0.61 mm yr−1. The inception age of individual fold structures follow closely this average rate, indicating that the system has been migrating at a constant rate for the past 17 Myr. Cumulative shortening of the system also increases linearly through time at 2.93 ± 0.31 mm yr−1. The location of the youngest structures in the easternmost portion of the system coincides with a significant peak of seismic moment released by historical earthquakes. We conclude that not only these easternmost thrusts are still active, but also that they generate earthquakes.
Environmental determinants of atopic eczema phenotypes in relation to asthma and atopic sensitization
Authors: Karadag B. , Ege M. J. , Scheynius A. , Waser M. , Schram‐Bijkerk D. , Van Hage M. , Pershagen G. , Brunekreef B. , Riedler J. , Braun‐Fahrländer C. , Von Mutius E. ,   the PARSIFAL Study team
Published: October 2007

Background:  There is still uncertainty about the determinants of atopic eczema (AE). To explain the heterogeneity of the disease, different phenotypes of AE have been suggested.Methods:  The cross‐sectional PARSIFAL study included 14 893 school‐age children of farmers or children attending Steiner schools and their respective reference groups. A detailed questionnaire was completed, and house dust was collected for the measurement of endotoxin and glucans. Atopic sensitization was defined by allergen‐specific IgE levels in the serum.Results:  In multivariate analyses, helping with haying was the only variable related to a farming environment having a consistent inverse association with both current symptoms and a doctor’s diagnosis of AE [aOR = 0.65 (95% CI: 0.46–0.93) and 0.73 (0.51–1.05)], respectively. Severe lower respiratory tract infections (LRTI) in the first 2 years of life and usage of antibiotics ever were found to be positively related only to asthma‐associated AE, whereas the effect of LRTI on AE without asthma had an opposite effect. Levels of β(1→3)‐glucans in mattress dust were inversely related to a doctor’s diagnosis of asthma‐associated AE [aOR = 0.75 (0.57–0.98)], and endotoxin levels to current symptoms of asthma‐associated AE [aOR = 0.73 (0.57–0.94)].Conclusions:  The analyses of the PARSIFAL study revealed two different phenotypes of AE, depending on the association with asthma and wheezing ever. With regard to the hygiene hypothesis, help with haying, exposure to β(1→3)‐glucans and endotoxin were found to be inversely associated with the AE phenotype associated with asthma and wheezing.