bluuebunny/crossref_metadata_2025 huggingface dataset:
Linear relationship between Gaeumannomyces graminis var. tritici (Ggt) genotypic frequencies and disease severity on wheat roots in the field
Authors: Lebreton Lionel , Gosme Marie , Lucas Philippe , Guillerm‐Erckelboudt Anne‐Yvonne , Sarniguet Alain
Published: November 2006

In order to investigate potential links existing between Gaeumannomyces graminis var. tritici (Ggt) population structure and disease development during polyetic take‐all epidemics in sequences of Ggt host cereals, seven epidemics in fields with different cropping histories were monitored during the seasons 2001/2002 (two fields), 2002/2003 (two fields) and 2003/2004 (three fields). Take‐all incidence and severity were measured at stem elongation and Ggt populations were characterized. The 73 isolates collected in the two fields in 2001/2002 were distributed into two multilocus genotypes, G1 and G2 according to amplified fragment length polymorphism analysis. A monolocus molecular marker amplified by F‐12 random amplification polymorphism DNA primer sizing between 1.9 and 2.0 kb that gave strictly the same distinction between the two multilocus genotypes was further applied to measure G1/G2 frequencies among Ggt populations in all fields (266 isolates). The ratios of G1 to G2 differed between fields with different cropping histories. A linear relationship between G2 frequency among Ggt populations and disease severity at stem elongation was measured during the three cropping seasons. When take‐all decline was observed, G2 frequencies were low in first wheat crops, highest in short‐term sequences and intermediate in longer sequences of consecutive crops of Ggt host cereals. This pattern could be the result of population selection by environmental conditions, in particular by microbial antagonism during the parasitic phase of the fungus. In order to better understand take‐all epidemic dynamics, the distinction between these two genotypes could be a basis to develop models that link approaches of quantitative epidemiology and advances in population genetics of Ggt.
On Semiparametric EV Models with Serially Correlated Errors in Both Regression Models and Mismeasured Covariates
Authors: YOU JINHONG , ZHOU HAIBO
Published: November 2006

Abstract. We consider inference for a semiparametric regression model where some covariates are measured with errors, and the errors in both the regression model and the mismeasured covariates are serially correlated. We propose a weighted estimating equations‐based estimator (WEEBE) for the regression coefficients. We show that the WEEBE is asymptotically more efficient than the estimators that neglect the serial correlations. This is an interesting new finding since earlier results in the statistical literature have shown that the weighted estimation is not as efficient as the unweighted estimation when the measurement errors and serially correlated errors of the regression models exist simultaneously (Biometrics, 49, 1993, 1262; Technometrics, 42, 2000, 137). The proposed WEEBE does not require undersmoothing the regressor functions in order to make it attain the root‐nconsistency. Simulation studies show that the proposed estimator has nice finite sample properties. A real data set is used to illustrate the proposed method.
Choosing between Alternative Classification Criteria to Measure the Labour Force State
Authors: Battistin Erich , Rettore Enrico , Trivellato Ugo
Published: November 2006

Labour force counting relies on general guidelines that are set by the International Labour Office to classify individuals into three labour force states: employment, unemployment and inactivity. However, the resulting statistics are known to be sensitive to slight variations in operational definitions which are prima facie consistent with the general guidelines. We consider two interpretations of the general guidelines, operationalized by the criterion that is currently followed by Eurostat and a criterion that was followed by the Italian Statistical Office up to 1992. After showing that the labour force statistics resulting from the two criteria differ considerably, we compare individuals whose classification depends on the criterion that is adopted with individuals whose classification is common between criteria to study the boundary between unemployment and inactivity. An application of our strategy is presented using data from the Italian Labour Force Survey, painting a picture neatly against the criterion that is currently followed by Eurostat.
Holistic Trajectories: a Study of Combined Employment, Housing and Family Careers by using Multiple-Sequence Analysis
Authors: Pollock Gary
Published: November 2006

Social science applications of sequence analysis have thus far involved the development of a typology on the basis of an analysis of one or two variables which have had a relatively low number of different states. There is a yet unexplored potential for sequence analysis to be applied to a greater number of variables and thereby a much larger state space. The development of a typology of employment experiences, for example, without reference to data on changes in housing, marital and family status is arguably inadequate. The paper demonstrates the use of sequence analysis in the examination of multivariable combinations of status as they change over time and shows that this method can provide insights that are difficult to achieve through other analytic methods. The data that are examined here provide support to intuitive understandings of clusters of common experiences which are both life course specific and related to socio-economic factors. Housing tenure is found to be of key importance in understanding the holistic trajectories that are examined. This suggests that life course trajectories are sharply differentiated by experience of social housing.
Are Football Referees Really Biased and Inconsistent?: Evidence on the Incidence of Disciplinary Sanction in the English Premier League
Authors: Dawson Peter , Dobson Stephen , Goddard John , Wilson John
Published: November 2006

The paper presents a statistical analysis of patterns in the incidence of disciplinary sanction (yellow and red cards) that were taken against players in the English Premier League over the period 1996–2003. Several questions concerning sources of inconsistency and bias in refereeing standards are examined. Evidence is found to support a time consistency hypothesis, that the average incidence of disciplinary sanction is predominantly stable over time. However, a refereeing consistency hypothesis, that the incidence of disciplinary sanction does not vary between referees, is rejected. The tendency for away teams to incur more disciplinary points than home teams cannot be attributed to the home advantage effect on match results and appears to be due to a refereeing bias favouring the home team.
Conditional Gaussian Mixture Modelling for Dietary Pattern Analysis
Authors: Fahey Michael T. , Thane Christopher W. , Bramwell Gemma D. , Coward W. Andy
Published: November 2006

Free-living individuals have multifaceted diets and consume foods in numerous combinations. In epidemiological studies it is desirable to characterize individual diets not only in terms of the quantity of individual dietary components but also in terms of dietary patterns. We describe the conditional Gaussian mixture model for dietary pattern analysis and show how it can be adapted to take account of important characteristics of self-reported dietary data. We illustrate this approach with an analysis of the 2000–2001 National Diet and Nutrition Survey of adults. The results strongly favoured a mixture model solution allowing clusters to vary in shape and size, over the standard approach that has been used previously to find dietary patterns.
The Impact of Education on the Diagnostic Accuracy of Tension-Type Headache and Migraine: A Prospective Study
Authors: Karli N , Zarifoglu M , Erer S , Pala K , Akis N
Published: November 2006

General practitioners (GPs) diagnose and treat headache in primary care settings. The objective of this study was to investigate the effect of a 2-day headache education programme for GPs primarily on diagnostic accuracy. The education programme included theoretical lectures and face-to-face patient evaluation with headache specialists. Three GPs evaluated headache patients before and after the programme. Each GP was planned to interview a total of 60 patients (30 before, 30 after the programme). All patients were evaluated by headache specialists following evaluation by the GPs. A total of 189 patients were included in this study. Diagnostic accuracy increased from 56.3% to 81.0% after the headache education programme ( P < 0.001), which also significantly improved the choice of proper treatment ( P = 0.043). The headache education programme for GPs significantly improved diagnostic accuracy in patients with tension-type headache and the choice of proper treatment. Such education programmes can be standardized and given to GPs working in the primary care setting. These programmes can be arranged locally by the universities and might have a favourable impact on the diagnosis and treatment of headache.
Neck Mobility and Forward Head Posture are not Related to Headache Parameters in Chronic Tension-Type Headache
Authors: Fernández-de-las-Peñas C , Alonso-Blanco C , Cuadrado ML , Pareja JA
Published: November 2006

The relationship between the changes in forward head posture (FHP), neck mobility and headache parameters was analysed in 25 patients with chronic tension-type headache (CTTH) undergoing a physical therapy programme. Side-view pictures were taken to measure the cranio-vertebral angle in the sitting and standing positions. A cervical goniometer was employed to measure the range of all cervical motions. A headache diary was kept to assess headache intensity, frequency and duration. All patients received six sessions of physical therapy over 3 weeks. Outcomes were assessed at baseline, after treatment and 1 month later. Neck mobility and headache parameters showed a significant improvement after the intervention, whereas posture changes did not reach statistical significance. No correlations were found between FHP, neck mobility and headache parameters at any stage. Changes in these outcomes throughout the study were not correlated either. FHP and neck mobility appear not to be related to headache intensity, duration or frequency in patients suffering from CTTH. Although patients showed a reduction in the range of motion in the neck, it is uncertain whether this is consistent with TTH.
Does avian species richness in natural patch mosaics follow the forest fragmentation paradigm?
Authors: Pavlacky D. C. , Anderson S. H.
Published: November 2006

As one approaches the north‐eastern limit of pinyon (Pinus spp.) juniper (Juniperus spp.) vegetation on the Colorado Plateau, USA, woodland patches become increasingly disjunct, grading into sagebrush (Artemisia spp.)‐dominated landscapes. Patterns of avian species richness in naturally heterogeneous forests may or may not respond to patch discontinuity in the same manner as bird assemblages in fragmented agricultural systems. We used observational data from naturally patchy woodlands and predictions derived from studies of human‐modified agricultural forests to estimate the effects of patch area, shape, isolation and distance to contiguous woodland on avian species richness. We predicted that patterns of species richness in naturally patchy juniper woodlands would differ from those observed in fragmented agricultural systems. Our objectives were to (1) estimate the effect of naturally occurring patch structure on avian species richness with respect to habitat affinity and migratory strategy and (2) assess the concordance of the effects to predictions from agricultural forest systems. We used the analogy between populations and communities to estimate species richness, where species are treated as individuals in the application of traditional capture–recapture theory. Information‐theoretic model selection showed that overall species richness was explained primarily by the species area relationship. There was some support for a model with greater complexity than the equilibrium theory of island biogeography where the isolation of large patches resulted in greater species richness. Species richness of woodland‐dwelling birds was best explained by the equilibrium hypothesis with partial landscape complementation by open‐country species in isolated patches. Species richness within specific migratory strategies showed concomitant increases and no shifts in species composition along the patch area gradient. Our results indicate that many patterns of species richness considered to be fragmentation effects may be general consequences of patch discontinuity and are ubiquitous in naturally heterogeneous systems. There was no evidence for the effects of patch shape and distance to contiguous woodland in juniper woodland, suggesting edge effects and dependence upon regional species pools are characteristics of fragmented agricultural systems. Natural patch mosaics may provide benchmarks for evaluating fragmentation effects and managing forests by mimicking natural landscape patterns.
Patch‐ and landscape‐scale effects on howler monkey distribution and abundance in rainforest fragments
Authors: Anzures‐Dadda A. , Manson R. H.
Published: November 2006

Variation at both the patch and landscape scale is known to influence the distribution and abundance of arboreal monkeys in rainforest fragments. However, few studies have examined the factors associated with these different scales of focus simultaneously. Using stepwise logistic‐regression and generalized linear models (GLMs), howler monkey Alouatta palliata distribution and abundance were examined as a function of patch quality (fragment area, shape, tree DBH and canopy height) and landscape connectivity (isolation, total forest area, fragment and road abundance, corridor abundance and length) in 119 rainforest fragments in northern Chiapas, Mexico. The positive correlation observed between monkey distribution (presence/absence) and both fragment area and abundance may be explained by increased resources within larger fragments and those whose proximity allows greater exploration by monkeys. In contrast, GLM analysis indicated that monkey abundance in inhabited fragments was positively correlated with corridor abundance, canopy height and fragment area. These relationships could be explained by greater reproductive investments by monkeys in forest fragments whose size, degree of perturbation and degree of connectivity with other fragments suggest greater overall resource availability. Future studies should explicitly include a multi‐scale approach to understanding the factors affecting patterns of monkey distribution and abundance, particularly as this relates to measures of and interactions between patch connectivity and resource availability.
Alarm responses are maintained during captive rearing in chicks of endangered kaki
Authors: Galbraith J. A. , Sancha S. E. , Maloney R. F. , Hauber M. E.
Published: November 2006

The maintenance of species‐specific behavioural repertoires and traditions is an important but often implicit goal of conservation efforts. When captive rearing is used as a conservation practice, it becomes critical to address its possible implications for the social and behavioural traits of developing individuals. In particular, animals must retain or acquire many of their behavioural abilities to increase the likelihood of survival upon release into the wild. This study investigated the behavioural development of critically endangered kaki (black stilt:Himantopus novaezelandiae) chicks reared without live adult conspecifics. The captive rearing programme included playbacks of adult kaki alarm calls during cleaning and handling of precocial chicks housed as groups. We used videotaped observations and playback experiments to address the following questions: do kaki chicks respond differentially to (1) familiar versus unfamiliar adult kaki alarm calls and (2) conspecific alarm versus heterospecific control vocalizations. Adult‐naïve kaki chicks exhibited a varied behavioural repertoire over their early development. In multivariate analyses, when age was statistically controlled, chicks showed responses to familiar and unfamiliar alarm calls that were similar in magnitude. In contrast, following conspecific alarm calls chicks had longer average latencies to resume pre‐playback activities than following heterospecific vocalizations. Although the generality of these conclusions is limited by experimental constraints stemming from working with an endangered species, the findings suggest that current management techniques produce captive‐reared kaki for release into the wild that possess many of the behavioural and auditory recognition skills that are required for survival.
Deconstructing myths on large gulls and their impact on threatened sympatric waterbirds
Authors: Oro D. , Martínez‐Abraín A.
Published: November 2006

Owing to increasing population trends and facultative predatory habits, large gulls have been identified as significant agents of change in the alteration of many ecological communities. Often, they are perceived as negatively impacting the population trends of most sympatric waterbirds. Consequently, culling programs have been implemented to remove adults, chicks and eggs intensively. Here, we review the interactions recorded in the literature between the yellow‐legged gullLarus michahellisand 10 sympatric waterbirds in the Mediterranean region, all threatened and classified as species of conservation concern. We also used 177 long‐term population trends derived from previous studies to study the population dynamics of these species and the culling effort performed. We show that gulls negatively affected survival, fecundity, foraging ecology and nesting habitat availability for many species. However, the annual population growth rates of most sympatric waterbirds showed positive values, even at sites where culling has yet to be initiated and local yellow‐legged gull populations are large and increasing. Our results suggest clearly that population increase has not been exclusive of yellow‐legged gulls, especially at the regional level. Yet, growth rates of both yellow‐legged gulls and sympatric waterbirds were positively associated. Strikingly, the population extinction rate was similar between colonies of yellow‐legged gulls and those of sympatric species. Thus, evidence exists to state that the success of gull control programs is relatively low in the long term. We recommend that conservation agencies heed several basic principles of population and community ecology before initiating control, for instance that (1) yellow‐legged gulls have bred historically with other bird species and have likely developed defensive mechanisms against this predator and (2) populations of large gulls are regulated by density‐dependent mechanisms in both space and time. Incoming European environmental policies on fishing discards and rubbish management should control more naturally and efficiently the density of large gulls and the composition of seabird communities in the long term.
A Novel Genetic Study of Chinese Families with Autosomal Recessive Retinitis Pigmentosa
Authors: Abd El‐Aziz M. M. , El‐Ashry M. F. , Chan W. M. , Chong K. L. , Barragan I. , Antiñolo G. , Pang C. P. , Bhattacharya S. S.
Published: November 2006

Autosomal recessive retinitis pigmentosa (arRP) is the commonest form of RP worldwide. To date 22 loci have been implicated in the pathogenesis of this disease; however none of these loci independently account for a significant proportion of recessive RP. Linkage studies of arRP in consanguineous families have been mainly based on homozygosity mapping, but this strategy cannot be applied in the case of non‐consanguineous families. Therefore, we implemented a systematic approach for identifying the disease locus in three non‐consanguineous Chinese families with arRP. Initially, linkage analysis using SNPs/microsatellite markers or mutation screening of known arRP genes excluded all loci/genes except RP25 on chromosome 6. Subsequently a whole genome scan for the three families using the 10K GeneChip Mapping Array was performed, in order to identify the possible disease locus. To the best of our knowledge this is the first report on the utilisation of the 10K GeneChip to study linkage in non‐consanguineous Chinese arRP. This analysis indicates that the studied families are probably linked to the RP25 locus, a well defined arRP locus in other populations. The identification of another ethnic group linked to RP25 is highly suggestive that this represents a major locus for arRP.
Neurotrophin and Trk neurotrophin receptors in the inner ear of Salmo salar and Salmo trutta
Authors: Catania S. , Germanà A. , Cabo R. , Ochoa‐Erena F. J. , Guerrera M. C. , Hannestad J. , Represa J. , Vega J. A.
Published: November 2006

Neurotrophins (NTs) and their signal transducing Trk receptors play a critical role in the development and maintenance of specific neuronal populations in the nervous system of higher vertebrates. They are responsible for the innervation of the inner ear cochlear and vestibular sensory epithelia. Neurotrophins and Trks are also present in teleosts but their distribution in the inner ear is unknown. Thus, in the present study, we used Western‐blot analysis and immunohistochemistry to investigate the expression and cell localization of both NTs and Trk receptors in the inner ear of alevins of Salmo salar and Salmo trutta. Western‐blot analysis revealed the occurrence of brain‐derived neurotrophic factor (BDNF) and neurotrophin‐3 (NT‐3), but not nerve growth factor (NGF), as well as all three Trk receptors, i.e. TrkA, TrkB and TrkC, the estimated molecular weights of which were similar to those expected for mammals. Specific immunoreactivity for neurotrophins was detected mainly in the sensory epithelia. In particular, BDNF immunoreactivity was found in the maculae of the utricle and saccule, whereas NT‐3 immunoreactivity was present in the sensory epithelium of the cristae ampullaris. As a rule the sensory epithelia of the inner ear lacked immunoreactivity for Trks, thus excluding possible mechanisms of autocrinia and/or paracrinia. By contrast, overlapping subpopulations of neurons in the statoacoustic ganglion expressed TrkA (about 15%), TrkB (about 65%) and TrkC (about 45%). The present results demonstrate that, as in mammals and birds, the inner ear of teleosts expresses the components of the neurotrophin–Trk system, but their roles remain to be elucidated.
Recent geography determines the distribution of some flying Hymenoptera in the Tuscan Archipelago
Authors: Dapporto L. , Wolf H. , Strumia F.
Published: November 2006

The aim of this paper is to examine whether current and/or Pleistocene geography affects the pattern of species richness and composition in two families of flying Hymenoptera in the Tuscan Archipelago (Italy). Faunistic data were obtained from the literature and from our own surveys. We used the Spearman rank correlation test to assess the influence on the richness of present‐day and Pleistocene island area and isolation. Moreover, we searched for patterns of similarity among the six examined islands of Tuscan Archipelago, with the adjacent Tuscan mainland and Sardinia and Corsica islands by cluster analysis (UPGMA) and by parsimony analysis of endemicity (PAE). Moreover, we verified whether the percentage of typical species of Tuscany and Sardo‐Corsican area is related to the recent and/or palaeogeographical distances of the islands from the two main fauna source pools. Isolation is the best predictor for species richness while Pleistocene area and Pleistocene isolation do not show any significant correlation. Cluster analysis and PAE show a biogeographic pattern where generally Capraia and Montecristo group together with Corsica, while Elba, Giglio, and Pianosa group with Tuscan mainland. Recent geography seems to also affect fauna compositions. Indeed the incidence of Tuscan and Sardo‐Corsican species is related to the present‐day island distance to Tuscany and Corsica. In conclusion, we strongly suggest that colonization of these islands acted by dispersal from Tuscany and Corsica, using Elba island as a stepping stone.
Foraging modes as suites of coadapted movement traits
Authors: Cooper W. E.
Published: November 2006

The nature and evolutionary bases of foraging modes remain uncertain despite intensive study. Whether species can be assigned to one of two foraging modes, ambush and active foraging, or to multiple modes, and whether modes exist or are extremes on continua of movements variables have been highly controversial. Bimodality of avian movements per minute (MPM) was claimed to support discreteness of modes, but lizards exhibit extensive unimodal variation. I present data for 58 lizard species on average speed (AS), speed while moving (MS), MPM and per cent time moving. Correlated evolution has occurred between the frequency, duration and speed of foraging movements, suggesting that these traits represent a coadapted suite of foraging movements. Cluster analysis using AS, MPM and per cent time moving assigned species to clusters isomorphic with traditional ambush and active foraging. Large empty regions in foraging space suggest that foraging modes represent adaptive peaks of suites of coevolved traits. All variables differed across clades and modes. Variation within taxa and modes suggests that historical and ecological factors determine modes. When MS replaces AS, four species change from ambush to the active cluster. Foraging modes are not fixed, discrete traits because substantial quantitative variation occurs within modes. All single movement variables are lognormally distributed, indicating that bimodality of single variables is not required for the existence of distinct foraging modes. As data on new taxa accumulate, gaps between clusters may be reduced and/or new modes identified. Currently, the two‐mode paradigm remains appealing due to its broad explanatory power and simplicity.
Niche overlap and resource partitioning between two sympatric fox species in southern Brazil
Authors: Vieira E. M. , Port D.
Published: November 2006

Mechanisms that favour the co‐occurrence of morphologically and ecologically similar species in South America are potentially relevant, because two or more species often occur in sympatry. In the present study, we investigated possible mechanisms of resource partitioning between two sympatric species of foxes, the crab‐eating foxCerdocyon thousand the pampas foxPseudalopex gymnocercus, in the National Park of Aparados da Serra in southern Brazil (29°10′S, 50°05′W). We considered three main niche dimensions – habitat, diet and time – and evaluated the overlap between the two species in these dimensions. We conducted the study from June 2000 to October 2001 in an area composed of open grasslands andAraucariaforests. We studied the foxes by using a combination of scat analysis and direct observation. A comparison of their diet indicated that it was very similar for both species in all seasons (Pianka's indexes ranging from 0.920 to 0.957). The most common food item for both species of foxes was rodents, followed by coleopterans, birds and plant remains (seeds and fruits). As expected by the niche‐complementarity hypothesis, we detected differences along other niche axes.Pseudalopex gymnocercusseemed to occur only in open areas, including grasslands and dirt roads, whereasC. thouswas more generalist in habitat use, occurring both inside and at the edge of forests. However, both fox species were common in grassland habitats, where they might compete for resources. The differences were more marked for activity time, with the crab‐eating fox being significantly more nocturnal (circular mean of time of sighting=23:39 h,se=56 min) than the pampas fox (circular mean=19:56 h,se=64 min; Watson'sF=6.06,P=0.02). We suggest that the largerC.thouscould be limiting the activity ofP.gymnocercusby interference competition.
Demography and environmental stochasticity: empirical estimates of survival in three grassland rodents
Authors: Reed A. W. , Slade N. A.
Published: November 2006

Environmental stochasticity in vital rates influences the dynamics of structured populations. Stochastic models of population dynamics often assume that vital rates vary independently, an assumption that may be violated in many populations. We estimated the survival of three species of grassland rodents – deer mouse Peromyscus maniculatus, white‐footed mouse Peromyscus leucopus and western harvest mouse Reithrodontomys megalotis– using a long‐term dataset. We used these data to assess the level of cross correlation and autocorrelation in stage‐specific survival rates and the correlation between survival and selected environmental variables. We found little evidence of correlation among survival estimates in any species or correlation between survival and environmental variables. In contrast to other species in the region, our analyses suggest that survival rates in deer mice, white‐footed mice and western harvest mice vary independently throughout the year.
Reproduction in the short‐nosed fruit bat in relation to environmental factors
Authors: Bumrungsri S. , Bumrungsri W. , Racey P. A.
Published: November 2006

The reproductive pattern of the short‐nosed fruit bat Cynopterus brachyotis in a tropical dry evergreen rainforest in Thailand (13°N) is characterized by seasonal bimodal polyoestry with postpartum oestrus. The first lactation period occurred in March–April, but the timing of the second varied between years: September–October in 1998 and July–August in 1999. Females may experience reproductive delays after the second parturition. Females attained sexual maturity at 6–7 months of age and gave birth for the first time at about 11–12 months, and are able to produce two young a year. Females born in April gave birth as early as March the following year. Those born in August–September first gave birth in July–August the following year. Males attained sexual maturity when they were a year old. Testis size was significantly positively correlated with photoperiod. The body weight of mature males varied cyclically, was higher during breeding periods and was significantly correlated with testis size. The first parturition coincided with the onset of the annual rains and the second occurred in the middle of the rainy season. Both lactation and weaning periods correspond with high food availability. A significantly higher percentage of reproductive females, earlier parturition, greater synchrony of lactation, higher body mass of lactating females, more abundant, larger and heavier juveniles, and heavier mature males were recorded in 1999 compared with 1998. The El Niño Southern Oscillation resulted in a prolonged and severe drought early in 1998, and induced mast fruiting in 1999 that led to higher reproductive success. Photoperiod may regulate the reproductive rhythm in male C. brachyotis, although experimental studies are required to verify this.
An ecomorphological analysis of extant small carnivorans
Authors: Friscia A. R. , Van Valkenburgh B. , Biknevicius A. R.
Published: November 2006

An ecomorphological study of extant small carnivorans demonstrates that dietary groups can be distinguished using quantitative morphological characters. Small (<10 kg) modern carnivorans were divided into three dietary classes: carnivores, insectivores and omnivores/hard‐object feeders. Statistical analyses revealed differences between these classes including longer carnassial blades in carnivorans, as opposed to larger molar grinding areas, larger post‐canine dentitions, and wider fourth premolars in omnivores/hard‐object feeders. Insectivores are not consistently distinguished from other dietary types, although they do tend to have weaker dentaries and shorter temporalis muscle moment arms. These trends can be used to help interpret morphologies of taxa of uncertain ecologies, including fossil taxa.
Recovery of a rodent community in an agro‐ecosystem after flooding
Authors: Zhang M. , Wang K. , Wang Y. , Guo C. , Li B. , Huang H.
Published: November 2006

The Dongting Lake region is one of the areas prone to flood disaster in China. Despite the frequent occurrence of flooding in this area, few studies have analysed its effects on rodent communities, especially their recovery after withdrawal of floodwaters. We carried out a study of rodent recovery after flooding of the Dongting Lake region in 1998. Rodent population monitoring in the flooded countryside of the Dongting Lake region was conducted during 1998–2001. The census was conducted in Anzao polder of Anxian County in Hunan Province, where the dike burst in 1998 and thousands of hectares of farmland were flooded from July to October. The results indicate that flood disaster could provide important changes in rodent community structure. Firstly, species abundance in the post‐flood area became less than in the normal area. Striped field mice Apodemus agrarius colonized the flooded area in farmland until March 2000, and Norway rats Rattus norvegicus and house mice Mus musculus occurred in July and December 2000, respectively. The degree of the effect on the rodent community in residential premises is less than that in farmland. However, the rodent community in the flooded area could recover and become similar to the normal community. The recovery of rodent species composition was faster in residential premises than in farmland after flooding. Secondly, there was a similar tendency of the dominant concentration indices between post‐flood and normal areas. Thirdly, inundation for a long period could reduce the species diversity of the rodent community in farmland. The significant difference in abundance was continued to 2000 in post‐flooded farmland; however, the influence on the rodent community in residential premises was less and their diversity indices did not differ in 1999. Similarity indices indicated that variation between post‐flood and normal areas had been gradually becoming low from 1999 to 2001. Finally, the monitoring data showed that rodent populations in the flooded area were less than those in the normal area in the first step after withdrawal of floodwaters. However, the rodent population increased rapidly in the flooded area, and became greater than that in the unflooded area in half a year. The population in the flooded area also increased faster than that in unflooded neighbouring area after the application of rodenticide. Another phenomenon was that the population density of rodents could reach levels greater than the normal area, and may continue for more than 2 years. Flood disasters could reduce population densities and species abundance, species diversity and evenness, while increasing dominant concentration indices of the rodent community. However, after 3 years, the rodent community structure became similar to that in the non‐flooded area, except for high density. The recovery of rodent communities in residential premises was faster than that in farmland for a lesser degree of flooding.
Oral administration of a potent and selective non‐peptidic BACE‐1 inhibitor decreases β‐cleavage of amyloid precursor protein and amyloid‐β production in vivo
Authors: Hussain Ishrut , Hawkins Julie , Harrison David , Hille Christopher , Wayne Gareth , Cutler Leanne , Buck Tania , Walter Daryl , Demont Emmanuel , Howes Colin , Naylor Alan , Jeffrey Philip , Gonzalez Maria I. , Dingwall Colin , Michel Anton , Redshaw Sally , Davis John B.
Published: November 2006

Generation and deposition of the amyloid β (Aβ) peptide following proteolytic processing of the amyloid precursor protein (APP) by BACE‐1 and γ‐secretase is central to the aetiology of Alzheimer's disease. Consequently, inhibition of BACE‐1, a rate‐limiting enzyme in the production of Aβ, is an attractive therapeutic approach for the treatment of Alzheimer's disease. We have designed a selective non‐peptidic BACE‐1 inhibitor, GSK188909, that potently inhibits β‐cleavage of APP and reduces levels of secreted and intracellular Aβ in SHSY5Y cells expressing APP. In addition, we demonstrate that this compound can effectively lower brain Aβin vivo. In APP transgenic mice, acute oral administration of GSK188909 in the presence of a p‐glycoprotein inhibitor to markedly enhance the exposure of GSK188909 in the brain decreases β‐cleavage of APP and results in a significant reduction in the level of Aβ40 and Aβ42 in the brain. Encouragingly, subchronic dosing of GSK188909 in the absence of a p‐glycoprotein inhibitor also lowers brain Aβ. This pivotal first report of central Aβ lowering, following oral administration of a BACE‐1 inhibitor, supports the development of BACE‐1 inhibitors for the treatment of Alzheimer's disease.
cAMP/protein kinase A signalling pathway protects against neuronal apoptosis and is associated with modulation of Kv2.1 in cerebellar granule cells
Authors: Jiao Song , Liu Zheng , Ren Wen‐Hua , Ding Yu , Zhang Yu‐Qiu , Zhang Zhi‐Hong , Mei Yan‐Ai
Published: November 2006

Previously, we have reported that apoptosis of cerebellar granular neurons induced by incubation in 5 mm K+ and serum‐free medium (LK‐S) was associated with an increase in the delayed rectifier K+ current (IK). Here, we show that IK associated with apoptotic neurons is mainly encoded by a Kv2.1 subunit. Silencing Kv2.1 expression by small interfering RNA reduces IK and increases neuron viability. Forskolin is able to decrease the IK amplitude recording from neurons of both the LK‐S and control group, and prevents apoptosis of granule cells that are induced by LK‐S. Dibutyryl cAMP mimicks the effect of forskolin on the modulation of IK and, accordingly, the inhibitor of protein kinase A, H‐89, aborts the neuron‐protective effect induced by forskolin. Whereas the expression of Kv2.1 was silenced by Kv2.1 small interfering RNA, the inhibition of forskolin on the current amplitude was significantly reduced. Quantitative RT‐PCR and whole‐cell recording revealed that the expression of Kv2.1 was elevated in the apoptotic neurons, and forskolin significantly depressed the expression of Kv2.1. We conclude that the protection against apoptosis via the protein kinase A pathway is associated with a double modulation on IK channel properties and its expression of α‐subunit that is mainly encoded by the Kv2.1 gene.
Green tea polyphenol (–)‐epigallocatechin‐3‐gallate promotes the rapid protein kinase C‐ and proteasome‐mediated degradation of Bad: implications for neuroprotection
Authors: Kalfon Limor , Youdim Moussa B. H. , Mandel Silvia A.
Published: November 2006

The aim of the present study was to gain a deeper insight into the cell signaling pathways involved in the neuroprotection/neurorescue activity of the major green tea polyphenol (–)‐epigallocatechin‐3‐gallate (EGCG). EGCG (1 μm) caused an immediate (30 min) down‐regulation (∼40%) of Bad protein levels, and a more pronounced reduction after 24 h (55%) in the human neuroblastoma cell line SH‐SY5Y. Co‐treatment with EGCG and the protein synthesis inhibitor cycloheximide prominently shortened Bad half‐life, with as little as 30% of the Bad protein content remaining after 2 h, suggesting an effect of EGCG on Bad protein degradation. Accordingly, the proteasome inhibitors MG‐132 and lactacystin damped Bad down‐regulation by EGCG. The general protein kinase C (PKC) inhibitor GF109203X, or the down‐regulation of conventional and novel PKC isoforms, abolished EGCG‐induced Bad decline. However, no inhibition was seen with the cell‐permeable myristoylated pseudosubstrate inhibitor of the atypical PKCζ isoform. The enforced expression of Bad for up to 72 h rendered the cells more susceptible to serum deprivation‐induced cell death, whereas EGCG treatment significantly improved cell viability (up to 1.6‐fold). The present study reveals a novel pathway in the neuroprotective mechanism of the action of EGCG, which involves a rapid PKC‐mediated degradation of Bad by the proteasome.
Isolation and characterization of microsatellite markers in pangolins (Mammalia, Pholidota, Manis spp.)
Authors: LUO SHU‐JIN , CAI QING‐XIU , DAVID VICTOR A. , ZHANG LI , MARTELLI PAOLO , LIM NORMAN T‐L. , FERRAND NUNO , CHIN SHIH‐CHIEN , GAUBERT PHILIPPE , RAMOS MARIA JOÃO , O’BRIEN STEPHEN J. , ANTUNES AGOSTINHO , JOHNSON WARREN E.
Published: November 2006

Thirty‐four polymorphic dinucleotide microsatellite loci were developed in the Malayan pangolin Manis javanica. Of the 34 markers, 32 and 18 were also amplified, respectively, in the Chinese pangolin (Manis pentadactyla) and the African tree pangolin (Manis tricuspis). Analysis of 24 Malayan, 12 Chinese and 2 African tree pangolins showed high levels of variability (heterozygosity ranging from 0.321 to 0.708). These are the first available microsatellite markers in Pholidota and will be an invaluable tool for evolutionary and conservation genetic studies in pangolins.
Characterization of simple sequence repeat markers derived in silico from Brassica rapa bacterial artificial chromosome sequences and their application in Brassica napus
Authors: LING ALISON E. , KAUR JATINDER , BURGESS BENJAMIN , HAND MELANIE , HOPKINS CLARE J. , LI XI , LOVE CHRISTOPHER G. , VARDY MEGAN , WALKIEWICZ MARZENA , SPANGENBERG GERMAN , EDWARDS DAVID , BATLEY JACQUELINE
Published: November 2006

A collaborative Brassica rapa genome sequencing project is currently in progress to aid the identification of agronomically important traits in Brassica species. As an initial stage, the ends of over 110 000 bacterial artificial chromosome clones were sequenced and mined for simple sequence repeats (SSRs). We present the characterization of 40 of these SSRs and their application in Brassica napus. The markers were screened against six Brassica species and Arabidopsis, and demonstrated reliable amplification, genome specificity, cross‐amplification and significant polymorphism. These SSRs will be useful for genetic analysis of Brassica germplasm.
A panel of microsatellite markers to detect and monitor demographic bottlenecks in the riverine dragonfly Orthetrum coerulescens F.
Authors: HADRYS HEIKE , WARGEL ANTONIA , GIERE SANDRA , KRAUS BERND , STREIT BRUNO
Published: November 2006

Odonates (dragonflies and damselflies) are important indicators for monitoring anthropogenic impacts on freshwater ecosystems. We developed a panel of microsatellite loci for the keeled skimmer Orthetrum coerulescens, a libellulid dragonfly inhabiting small streams. By using two different isolation techniques, nine microsatellite loci have been isolated. Screening of 209 individuals resulted in an overall number of 88 alleles, ranging from three to 19 alleles per locus. The observed heterozygosity ranged from 0.37 to 0.83. One locus showed significant deviation from Hardy–Weinberg equilibrium.
A set of polymorphic microsatellite loci for the bay scallop, Argopecten irradians
Authors: LI HONGJUN , LIU XIAO , HU JINGJIE , BAO ZHENMIN , ZHANG GUOFAN
Published: November 2006

The method of creating enriched microsatellite libraries can supply an abundant source of microsatellite sequences at a considerably reduced cost. Here we report the development of 15 polymorphic microsatellite loci from the bay scallop, Argopecten irradians, using enrichment protocol. Polymorphism was assessed in a sample of hatchery population (n = 38) revealing three to seven alleles per locus. The expected and observed heterozygosities ranged from 0.198 to 0.813 and from 0.083 to 0.833, respectively. These markers will be useful for genetic variation monitoring and parentage analysis.
Isolation and characterization of six microsatellites in the Mexican beaded lizard Heloderma horridum
Authors: FELTOON ANGELA R. , GUERRA TRINA , LEHN CATHI , FORSTNER MICHAEL R. J.
Published: November 2006

Six polymorphic microsatellite loci were isolated and characterized in the threatened Mexican beaded lizard, Heloderma horridum. The number of alleles per locus ranged from three to 12, with observed heterozygosity estimates ranging from 0.00 to 0.77, and expected heterozygosity estimates ranging from 0.00 to 0.73. These microsatellites will provide a valuable tool for the investigation of the genetic variation and structure of both wild and captive H. horridum populations.
Microsatellite markers for the June sucker (Chasmistes liorus mictus), Utah sucker (Catostomus ardens), and five other catostomid fishes of western North America
Authors: CARDALL B. L. , BJERREGAARD L. S. , MOCK K. E.
Published: November 2006

We developed and optimized five new microsatellite markers for the genetic management of the endangered June sucker. We report the cross‐amplification of these markers, and seven microsatellites previously developed for Klamath Basin suckers, in seven catostomid species of western North America. No linkage disequilibrium was detected between pairs of loci. Since most of these loci exhibited conserved priming sites, they may be useful for landscape‐scale studies of speciation and patterns of gene flow among multiple sucker lineages.
Identification of microsatellite loci from Epimedium koreanum and cross‐species amplification in four species of Epimedium (Berberidaceae)
Authors: ZHOU JIANFENG , XU YANQIN , HUANG HONGWEN , WANG YING
Published: November 2006

Nineteen polymorphic microsatellite markers were isolated and characterized from a trinucleotide enriched partial genomic library of Epimedium koreanum. The average allele number of these microsatellites was 5.9 per locus, ranging from two to 11. The observed heterozygosity (HO) and expected heterozygosity (HE) at the population level were 0.00–0.90 and 0.12–0.90, respectively. In addition, the results of cross‐species amplification of this set of microsatellite markers in four closely related Epimedium species, E. brevicornum, E. sagittatum, E. pubescens and E. wushanense, revealed that these microsatellite markers were useful for population genetic structure evaluation and genotype analysis of major Epimedium species that have been used as traditional Chinese medicines.
Characterization of microsatellite DNA markers for the alligator snapping turtle, Macrochelys temminckii
Authors: HACKLER JOSEPH C. , VAN DEN BUSSCHE RONALD A. , LESLIE DAVID M.
Published: November 2006

Two trinucleotide and seven tetranucleotide microsatellite loci were isolated from an alligator snapping turtle Macrochelys temminckii. To assess the degree of variability in these nine microsatellite loci, we genotyped 174 individuals collected from eight river drainage basins in the southeastern USA. These markers revealed a moderate degree of allelic diversity (six to 16 alleles per locus) and observed heterozygosity (0.166–0.686). These polymorphic microsatellite loci provide powerful tools for population genetic studies for a species that is afforded some level of conservation protection in every state in which it occurs.
Isolation and characterization of microsatellite loci in the flat‐headed bat (Tylonycteris pachypus)
Authors: HUA P. Y. , CHEN J. P. , ZHANG L. B. , LIANG B. , ROSSITER S. J. , ZHANG S. Y.
Published: November 2006

Microsatellite loci were developed in the flat‐headed bat (Tylonycteris pachypus) from genomic DNA using an enriched library method. Nine loci were tested on 48 individuals sampled from Guangxi Province, China. The mean number of observed alleles per locus was 6.4 (range 4–12). Observed and expected heterozygosity values ranged from 0.24 to 0.83 and from 0.30 to 0.89, respectively. One locus revealed significant departure from Hardy–Weinberg equilibrium and no significant linkage disequilibrium was detected between loci pairs. These markers will be used to examine genetic structure and parentage analysis in this species.