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Selected AbstractsA comparison of cross-hole electrical and seismic data in fractured rockGEOPHYSICAL PROSPECTING, Issue 2 2004J.V. Herwanger ABSTRACT Cross-hole anisotropic electrical and seismic tomograms of fractured metamorphic rock have been obtained at a test site where extensive hydrological data were available. A strong correlation between electrical resistivity anisotropy and seismic compressional-wave velocity anisotropy has been observed. Analysis of core samples from the site reveal that the shale-rich rocks have fabric-related average velocity anisotropy of between 10% and 30%. The cross-hole seismic data are consistent with these values, indicating that observed anisotropy might be principally due to the inherent rock fabric rather than to the aligned sets of open fractures. One region with velocity anisotropy greater than 30% has been modelled as aligned open fractures within an anisotropic rock matrix and this model is consistent with available fracture density and hydraulic transmissivity data from the boreholes and the cross-hole resistivity tomography data. However, in general the study highlights the uncertainties that can arise, due to the relative influence of rock fabric and fluid-filled fractures, when using geophysical techniques for hydrological investigations. [source] Optimal environmental and industrial policies and imperfect agglomeration effectsREGIONAL SCIENCE POLICY AND PRACTICE, Issue 2 2009Daisuke Ikazaki Agglomeration; technology; environment Abstract This paper examines a simple general equilibrium model that considers problems related to agglomeration, technology, and the environment. First, it is shown that the manufactured goods sector converts from classical technology with constant returns to scale to modern technology with increasing returns to scale as the regional population increases. The optimal pollution level might be an inverted-U shape with respect to population if optimal environmental policy is adopted. Second, the optimal population level of conversion is not attained in the market economy. The labour that is devoted to the manufactured goods sector in the market economy is too small. So, we derive the optimal subsidy rates to the manufactured goods sector to make resource allocation optimum. Third, we consider migration using the two-region model. One region becomes a large city and the other region becomes a rural area if the total population is large. The industrial policy tends to extend the population difference between city and rural areas. On the other hand, if the total population is small, a symmetric point will be stable equilibrium. [source] Comparative genomic and expression analysis of group B1 sox genes in zebrafish indicates their diversification during vertebrate evolutionDEVELOPMENTAL DYNAMICS, Issue 3 2006Yuich Okuda Abstract Group B1 Sox genes encode HMG domain transcription factors that play major roles in neural development. We have identified six zebrafish B1 sox genes, which include pan-vertebrate sox1a/b, sox2, and sox3, and also fish-specific sox19a/b. SOX19A/B proteins show a transcriptional activation potential that is similar to other B1 SOX proteins. The expression of sox19a and sox3 begins at approximately the 1,000-cell stage during embryogenesis and becomes confined to the future ectoderm by the shield stage. This is reminiscent of the epiblastic expression of Sox2 and/or Sox3 in amniotes. As development progresses, these six B1 sox genes display unique expression patterns that overlap distinctly from one region to another. sox19a expression is widespread in the early neuroectoderm, resembling pan-neural Sox2 expression in amniotes, whereas zebrafish sox2 shows anterior-restricted expression. Comparative genomics suggests that sox19a/b and mammalian Sox15 (group G) have an orthologous relationship and that the B1/G Sox genes arose from a common ancestral gene through two rounds of genome duplication. It seems likely, therefore, that each B1/G Sox gene has gained a distinct expression profile and function during vertebrate evolution. Developmental Dynamics 235:811,825, 2006. © 2006 Wiley-Liss, Inc. [source] The transferability of distribution models across regions: an amphibian case studyDIVERSITY AND DISTRIBUTIONS, Issue 3 2009Flavio Zanini ABSTRACT Aim, Predicting species distribution is of fundamental importance for ecology and conservation. However, distribution models are usually established for only one region and it is unknown whether they can be transferred to other geographical regions. We studied the distribution of six amphibian species in five regions to address the question of whether the effect of landscape variables varied among regions. We analysed the effect of 10 variables extracted in six concentric buffers (from 100 m to 3 km) describing landscape composition around breeding ponds at different spatial scales. We used data on the occurrence of amphibian species in a total of 655 breeding ponds. We accounted for proximity to neighbouring populations by including a connectivity index to our models. We used logistic regression and information-theoretic model selection to evaluate candidate models for each species. Location, Switzerland. Results, The explained deviance of each species' best models varied between 5% and 32%. Models that included interactions between a region and a landscape variable were always included in the most parsimonious models. For all species, models including region-by-landscape interactions had similar support (Akaike weights) as models that did not include interaction terms. The spatial scale at which landscape variables affected species distribution varied from 100 m to 1000 m, which was in agreement with several recent studies suggesting that land use far away from the ponds can affect pond occupancy. Main conclusions, Different species are affected by different landscape variables at different spatial scales and these effects may vary geographically, resulting in a generally low transferability of distribution models across regions. We also found that connectivity seems generally more important than landscape variables. This suggests that metapopulation processes may play a more important role in species distribution than habitat characteristics. [source] Regional differences in kelp-associated algal assemblages on temperate limestone reefs in south-western AustraliaDIVERSITY AND DISTRIBUTIONS, Issue 6 2003Thomas Wernberg Abstract.,Ecklonia radiata (C. Agardh) J. Agardh kelp beds , a characteristic feature of the nearshore environment along the south-west Australian coastline , contribute significantly to the coastal biodiversity in temperate Australia, yet, little is known about the organization of these macroalgal assemblages. By compiling existing and new data sets from habitat surveys, we have characterized and compared the structure of kelp-associated macroalgal assemblages in three regions (Marmion Lagoon, Hamelin Bay and the marine environment neighbouring the Fitzgerald River National Park) across more than 1000 kilometres of the south-west Australian coastline. 152 macroalgal taxa had been recognized within the three regions and this is in the range of species richness reported from other Australian and African kelp beds. The kelp-associated algal assemblages were regionally distinct, 66% of all taxa were only found in one region and only 17 taxa were found in all three regions. Adjacent regions shared an additional 13,15 taxa. The regional shifts in assemblage structure were evident in species composition of both canopy and understorey. The organization of assemblages followed a spatial hierarchy where differences in assemblage structure were larger among regions (hundreds of kilometres apart) than among sites within regions (kilometres apart) and differences among sites within region were larger than differences among quadrats within sites (metres apart). Despite this hierarchy each level of nesting contributed approximately the same to total variation in assemblage structure and these spatial patterns were stronger than temporal differences from seasons to 2,3 years. Our results suggest that local and small-scale processes contribute considerably to heterogeneity in macroalgal assemblages throughout south-western Australia, and, in particular, our results are consistent with E. radiata exerting a strong influence on macroalgal assemblage structure. Further, our study contradicts the existence of a general south-west Australian kelp assemblage, although a few species may form the core of E. radiata associations across regions. [source] Unemployment clusters across Europe's regions and countriesECONOMIC POLICY, Issue 34 2002Henry G. Overman Summary High unemployment and regional inequalities are major concerns for European policy-makers, but so far connections between policies dealing with unemployment and regional inequalities have been few and weak. We think that this should change. This paper documents a regional and transnational dimension to unemployment , i.e., geographical unemployment clusters that do not respect national boundaries. Since the mid 1980s, regions with high or low initial unemployment rates saw little change, while regions with intermediate unemployment moved towards extreme values. During this polarization, nearby regions tended to share similar outcomes due, we argue, to spatially related changes in labour demand. These spatially correlated demand shifts were due in part to initial clustering of low-skilled regions and badly performing industries, but a significant neighbour effect remains even after controlling for these, and the effect is as strong within as it is between nations. We believe this reflects agglomeration effects of economic integration. The new economic geography literature shows how integration fosters employment clusters that need not respect national borders. If regional labour forces do not adjust, regional unemployment polarization with neighbour effects can result. To account for these ,neighbour effects' a cross-regional and transnational dimension should be added to national anti-unemployment policies. Nations should consider policies that encourage regional wage setting, and short distance mobility, and the EU should consider including transnational considerations in its regional policy, since neighbour effects on unemployment mean that an anti-unemployment policy paid for by one region will benefit neighbouring regions. Since local politicians gain no votes or tax revenues from these ,spillovers', they are likely to underestimate the true benefit of the policy and thus tend to undertake too little of it. [source] Consistent Localization of Interictal Epileptiform Activity on EEGs of Patients with Tuberous Sclerosis ComplexEPILEPSIA, Issue 3 2005Floor E. Jansen Summary:,Purpose: We addressed consistent localization of focal interictal epileptiform activity on EEGs of patients with tuberous sclerosis complex (TSC) and epilepsy. Methods: Twenty-one patients with TSC with a 10-year history of epilepsy and interictal epileptiform activity in three or more EEG recordings were included. None of the patients had undergone epilepsy surgery. Local maxima of interictal epileptiform activity were measured from 76 EEG traces and 33 EEG reports. Information about the patients' clinical course was extracted from their medical records. Magnetic resonance imaging (MRI) and neuropsychological examinations were performed. Statistical analysis was performed with the Mann,Whitney U test. Results: In eight patients, interictal epileptiform activity was consistently detected in one or two regions (group 1), and in 13 patients, epileptiform activity was detected in three or more regions (group 2). The number of foci increased throughout the disease course in both groups. Age at seizure onset and IQ were significantly higher in group 1. Complex partial seizures occurred more often in the patients of group 1. In 19 of the 21 patients, the most consistent epileptiform activity was localized in the frontotemporal region. Conclusions: Ninety percent of patients with TSC showed at least one region of consistent interictal epileptiform activity. Patients with one or two regions of epileptiform activity were older at seizure onset, often experienced complex partial seizures, and had mild or no mental deficits. These patients may be candidates for epilepsy surgery. [source] Identification of the principal viruses infecting tomato crops in TunisiaEPPO BULLETIN, Issue 2 2000A. Ben Moussa Serological tests have been used to detect viruses associated with tomato in 257 samples collected in different regions in Tunisia, Cap-Bon, Sahel and South during successive seasons. The viruses detected were cucumber mosaic cucumovirus (CMV) and tomato aspermy cucumovirus (TAV), potato Y potyvirus (PVY), tobacco etch potyvirus (TEV) and pepper veinal mottle potyvirus (PVMV), tomato mosaic tobamovirus (ToMV) and tobacco mosaic tobamovirus (TMV), tobacco rattle tobravirus (TRV), alfalfa mosaic alfamovirus (AMV), tomato spotted wilt tospovirus (TSWV), tomato ringspot nepovirus (TomRSV) and potato X potexvirus (PVX). Some were detected in all three regions surveyed, at variable frequencies: TMV, CMV, TEV, PVY, ToMV, AMV, TAV, TSWV and TRV. Others were only detected in two regions (PVMV in Cap-Bon and Sahel and PVX in Sahel and in the south) or one region (TomRSV in Cap-Bon). Movement of individual viruses from one region to another may be due to movement of specific vectors, as in the case of the thrips-transmitted TSWV moving from the south to the north. Some of these viruses were found for the first time in Tunisia. [source] Wavelet analysis of the scale- and location-dependent correlation of modelled and measured nitrous oxide emissions from soilEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 1 2005A. E. Milne Summary We used the wavelet transform to quantify the performance of models that predict the rate of emission of nitrous oxide (N2O) from soil. Emissions of N2O and other soil variables that influence emissions were measured on soil cores collected at 256 locations across arable land in Bedfordshire, England. Rate-limiting models of N2O emissions were constructed and fitted to the data by functional analysis. These models were then evaluated by wavelet variance and wavelet correlations, estimated from coefficients of the adapted maximal overlap discrete wavelet transform (AMODWT), of the fitted and measured emission rates. We estimated wavelet variances to assess whether the partition of the variance of modelled rates of N2O emission between scales reflected that of the data. Where the relative distribution of variance in the model is more skewed to coarser scales than is the case for the observation, for example, this indicates that the model predictions are too smooth spatially, and fail adequately to represent some of the variation at finer scales. Scale-dependent wavelet correlations between model and data were used to quantify the model performance at each scale, and in several cases to determine the scale at which the model description of the data broke down. We detected significant changes in correlation between modelled and predicted emissions at each spatial scale, showing that, at some scales, model performance was not uniform in space. This suggested that the influence of a soil variable on N2O emissions, important in one region but not in another, had been omitted from the model or modelled poorly. Change points usually occurred at field boundaries or where soil textural class changed. We show that wavelet analysis can be used to quantify aspects of model performance that other methods cannot. By evaluating model behaviour at several scales and positions wavelet analysis helps us to determine whether a model is suitable for a particular purpose. [source] Simultaneous localization of two linked disease susceptibility genesGENETIC EPIDEMIOLOGY, Issue 1 2005Joanna M. Biernacka Abstract For diseases with complex genetic etiology, more than one susceptibility gene may exist in a single chromosomal region. Extending the work of Liang et al. ([2001] Hum. Hered. 51:64,78), we developed a method for simultaneous localization of two susceptibility genes in one region. We derived an expression for expected allele sharing of an affected sib pair (ASP) at each point across a chromosomal segment containing two susceptibility genes. Using generalized estimating equations (GEE), we developed an algorithm that uses marker identical-by-descent (IBD) sharing in affected sib pairs to simultaneously estimate the locations of the two genes and the mean IBD sharing in ASPs at these two disease loci. Confidence intervals for gene locations can be constructed based on large sample approximations. Application of the described methods to data from a genome scan for type 1 diabetes (Mein et al. [1998] Nat. Genet. 19:297,300) yielded estimates of two putative disease gene locations on chromosome 6, approximately 20 cM apart. Properties of the estimators, including bias, precision, and confidence interval coverage, were studied by simulation for a range of genetic models. The simulations demonstrated that the proposed method can improve disease gene localization and aid in resolving large peaks when two disease genes are present in one chromosomal region. Joint localization of two disease genes improves with increased excess allele sharing at the disease gene loci, increased distance between the disease genes, and increased number of affected sib pairs in the sample. Genet. Epidemiol. © 2004 Wiley-Liss, Inc. [source] Is hospital admission a sufficiently sensitive outcome measure for evaluating medication review services?INTERNATIONAL JOURNAL OF PHARMACY PRACTICE, Issue 2 2007A descriptive analysis of admissions within a randomised controlled trial Objective The aims of the study were: to describe and assess hospital admissions occurring during a randomised controlled trial (RCT) of a pharmacist-led medication review service; to describe the admissions in terms of emergency status and main cause; to estimate the potential contribution of pharmaceutical care issues (PCIs) to admission; and to assess the proportion of admissions that could be influenced by a pharmacist intervention. Setting Within the context of a RCT of pharmacists providing medication review for 332 elderly patients living at home, taking at least four repeat medicines, carried out in one region of Scotland. Method Hospital data were obtained for all admissions occurring during the 9-month period studied, summarised and evaluated by two independent medical reviewers for the contribution of PCIs to admission. Two pharmacists assessed the extent to which PCIs were preventable by pharmacist intervention. Key findings Approximately two-thirds of the 77 admissions were unplanned, and two-thirds were to medical wards. Only 17 (22%) of all admissions were considered to be related to PCIs and 10 (13%) possibly preventable by pharmacist intervention. Although the majority of surgical admissions were considered to be unrelated to PCIs (26/29), both unplanned and planned medical admissions were related to PCIs. One of these occurred as a direct result of the pharmacist's recommendation. Conclusion The overall numbers of hospital admissions, medical admissions and unplanned admissions may not be sufficiently sensitive outcome measures for evaluating the impact of pharmacist interventions. Consideration could be given to developing categories of admission that are related to medicines or are likely to be preventable as more relevant measures. Including more details of hospital admissions in future studies may be useful. [source] Musculoskeletal Pain and Risk for Falls in Older Disabled Women Living in the CommunityJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 4 2002Suzanne G. Leveille PhD OBJECTIVES: To determine whether musculoskeletal pain increased risk for falls in older women with disabilities. DESIGN: Prospective population-based cohort study. SETTING: The city and county of the eastern area of Baltimore. PARTICIPANTS: One thousand two women aged 65 and older, participants in the Women's Health and Aging Study, representing the one-third of older women who were living at home with disabilities, followed semiannually for 3 years beginning in 1991. MEASUREMENTS: Pain was categorized into four groups according to severity and location. Widespread pain was defined as pain in the upper and lower extremities and in the axial skeletal region, with moderate to severe pain in at least one region (, 4 on a 10-point numeric rating scale, 10 = excruciating pain). Moderate to severe lower extremity pain that did not meet criteria for widespread pain was the next category. The reference category was no pain or mild pain in one site. The additional category of "other pain" was pain that did not fit into the other three groups. The occurrence of falls and fall-related injuries were assessed at each interview. RESULTS: Of the 940 women who participated in at least one follow-up examination, 39% fell in first year; of the survivors, 36% fell in Year 2, and 39% in Year 3. After adjusting for several major risk factors for falls, women with widespread pain had an increased likelihood of falling during follow-up (adjusted odds ratio (AOR) = 1.66, 95% confidence interval (CI) = 1.25,2.21) compared with those with no or mild pain in only one musculoskeletal site. Women who had other musculoskeletal pain but not widespread pain or lower extremity pain also had an increased risk of falls (AOR = 1.36, 95% CI = 1.02,1.82). Among women with musculoskeletal pain, risk for falls was lower in those who used daily analgesic medication. Risk for recurrent falls and self-reported fractures due to falls was also elevated in women with musculoskeletal pain, most consistently in women with widespread pain. CONCLUSIONS: Musculoskeletal pain, particularly widespread pain, is a substantial risk factor for falls in older women with disabilities. These findings add an important dimension to our understanding of the multifactorial processes leading to falls in older persons. J Am Geriatr Soc 50:671,678, 2002. [source] Stable genetic polymorphism in heterogeneous environments: balance between asymmetrical dispersal and selection in the acorn barnacleJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 2 2006D. VÉLIZ Abstract Elucidating the processes responsible for maintaining polymorphism at ecologically relevant genes is intimately related to understanding the interplay between selection imposed by habitat heterogeneity and a species' capacity for dispersal in the face of environmental constraints. In this paper, we used a model-based approach to solve equilibria of balanced polymorphism, given values of fitness and larval dispersal among different habitats in the acorn barnacle Semibalanus balanoides from the Gulf of St Lawrence. Our results showed that allele frequencies observed at both MPI* and GPI* loci represented stable equilibria, given empirical estimates of fitness values, and that considerably more larvae dispersed from one region (north) to the other (south) than vice versa. Dispersal conditions were predicted to be similar for the maintenance of polymorphism at both loci. Moreover, the values of asymmetrical dispersal required by the model to reach stable equilibria were compatible with empirical estimates of larval dispersal and oceanic circulation documented in this system. Overall, this study illustrated the usefulness of a modified and computable version of Bulmer's model (1972) in order to test hypotheses of balanced polymorphism resulting from interactions between spatial selection and asymmetrical dispersal. [source] U.S. Sourcing from Low-Cost Countries: A Comparative Analysis of Supplier PerformanceJOURNAL OF SUPPLY CHAIN MANAGEMENT, Issue 4 2007Kusumal Ruamsook SUMMARY Given the increase in sourcing from low-cost countries (LCCs), it is important to assess relative supplier performance across these regions. This work investigates the comparative performance of LCC suppliers on 14 operational indicators of international sourcing and supply chain performance. Using survey methods, the study addresses these two questions: (1) How do the LCC regions of Asia, the Western Hemisphere and Europe compare in terms of the 14 operational indicators?; and (2) How do LCC nations within these three regions compare with regard to the 14 operational indicators? Perceived differences exist among the regions of Asia, the Western Hemisphere and Europe, as well as among the LCC nations of these three regions. However, no one region outperforms the others, and no one nation outperforms the others, on all 14 operational indicators investigated. Accordingly, this study also identifies the key areas of comparative advantage and disadvantage that each LCC region and each LCC nation presents in its relationship with U.S. buying firms. [source] Enhancement of waveguide model for propagation-loss prediction in tunnelsMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 1 2001Y. P. Zhang Abstract For microcellular system design, we have enhanced a well-known waveguide model for propagation-loss prediction along an LOS propagation path in a tunnel. It is reported in this letter. The enhancement involves a more accurate calculation of the tilt loss, the distinction of the two propagation regions, and the suggestion of using the free-space model for one region and the waveguide model for the other. The enhancement is demonstrated with examples. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 30: 10,12, 2001. [source] Ongoing ecological divergence in an emerging genomic modelMOLECULAR ECOLOGY, Issue 14 2009MATTHEW E. ARNEGARD Much of Earth's biodiversity has arisen through adaptive radiation. Important avenues of phenotypic divergence during this process include the evolution of body size and life history (Schluter 2000). Extensive adaptive radiations of cichlid fishes have occurred in the Great Lakes of Africa, giving rise to behaviours that are remarkably sophisticated and diverse across species. In Tanganyikan shell-brooding cichlids of the tribe Lamprologini, tremendous intraspecific variation in body size accompanies complex breeding systems and use of empty snail shells to hide from predators and rear offspring. A study by Takahashi et al. (2009) in this issue of Molecular Ecology reveals the first case of genetic divergence between dwarf and normal-sized morphs of the same nominal lamprologine species, Telmatochromis temporalis. Patterns of population structure suggest that the dwarf, shell-dwelling morph of T. temporalis might have arisen from the normal, rock-dwelling morph independently in more than one region of the lake, and that pairs of morphs at different sites may represent different stages early in the process of ecological speciation. The findings of Takahashi et al. are important first steps towards understanding the evolution of these intriguing morphs, yet many questions remain unanswered about the mating system, gene flow, plasticity and selection. Despite these limitations, descriptive work like theirs takes on much significance in African cichlids due to forthcoming resources for comparative genomics. [source] Phylogeography and population structure of an ecotonal marsupial, Bettongia tropica, determined using mtDNA and microsatellitesMOLECULAR ECOLOGY, Issue 12 2000L. C. Pope Abstract The northern bettong, Bettongia tropica, is an endangered species of Potoroidae with a restricted distribution in the wet tropics of north Queensland, Australia. The species is only found within a thin strip of sclerophyll forest along the western margin of rainforest. This tight association with rainforest boundaries is predicted to have resulted in population isolation as rainforest contracted during the Pleistocene, though some have proposed that the northern bettong was not present in the wet tropics until the late Pleistocene. The dispersal ability of the species, and of the family, is not known. This study examined gene flow among populations within areas of continuous habitat complemented by a broader analysis of phylogeography. Individuals trapped at each of the four known regions (one region was subsampled at three different sites), were sequenced for 547 base pairs of the mitochondrial DNA (mtDNA) control region and typed for seven microsatellite loci. The mtDNA phylogeny showed congruence with a biogeographical hypothesis, a relatively deep split suggesting historical isolation in separate northern and southern refugia. The two divergent clades were both present within the Lamb Range, indicating an expansion from these refuges and subsequent admixture at one site. mtDNA allele frequencies indicated relatively limited gene flow within the Lamb Range over distances as short as nine km. Tests of population divergence using microsatellites (FST and assignment tests) strongly supported this result. A molecular signal indicative of a recent bottleneck was unexpectedly detected in one of the Lamb Range subpopulations. This lead us to examine the behaviour of the statistics used in this bottleneck test under a linear stepping-stone model with varying migration rates. We found that it may be more difficult to detect molecular signatures for recent bottlenecks under conditions of very low migration rates than for isolated populations and, conversely, that ,false' bottleneck signatures may be observed at higher migration rates. The Lamb Range FST estimate clearly fell within the category of potentially ,false' bottleneck signals. Despite relatively limited gene flow, evidence for asymmetric dispersal suggests more complicated population dynamics than a simple linear stepping-stone model. [source] Reliability bounds for the NBUE distributionsNAVAL RESEARCH LOGISTICS: AN INTERNATIONAL JOURNAL, Issue 8 2002Kan Cheng Abstract In this paper, we study upper and lower bounds on the reliability in new better than used in expectation (NBUE) life distribution class with fixed first two moments. By a constructive proof, we determine the upper bounds on the reliability analytically in different regions and show that these bounds are sharp. For the lower bounds, similar results are obtained except in one region. For that region, a conjecture is given for further study. © 2002 Wiley Periodicals, Inc. Naval Research Logistics 49: 781,797, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/nav.10035 [source] Standard and Swedish variant types of the hybrid alder Phytophthora attacking alder in Hungary,PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 4 2003Zoltán Á Nagy Abstract A new Phytophthora disease of common alder (Alnus glutinosa) similar to that previously reported in several countries in Europe has been observed in Hungary. Based on these earlier studies, the alder Phytophthora was considered likely to be a hybrid between P cambivora and a P fragariae -like species: across Europe a range of new alder Phytophthora is spreading that comprise a range of heteroploid hybrids including a ,standard' hybrid type and several other hybrid types termed ,variants'. Phenotypic and molecular features of the pathogen in Hungary were characterised and compared with isolates from elsewhere. The morphologies of five isolates from one region (Hévíz) resembled the common, ,standard' type, whereas the three isolates from another region (Hanság) exhibited traits similar to those of one of the ,variant' types, ie the Swedish ,variant'. Molecular markers of these two groups of Hungarian isolates also represented a good fit to those of the standard type and the Swedish variant, respectively. Isozyme patterns and profiles of restriction fragments of the entire internal transcribed spacer (ITS) region or mitochondrial DNAs and of RAPD-PCR products did not differ within a group, but distinct polymorphisms were exhibited between the two groups of isolates. Southern analysis of random amplified polymorphic DNA (RAPD) revealed the homologous nature of co-migrating bands of P cambivora and the isolates of alder Phytophthora. Furthermore, restriction fragment profiles of the ITS region of ribosomal DNAs and the mtDNAs were consistent with reported biparental origin of alder Phytophthora. The hybrid status of these continuously evolving pathogens raises many issues and challenges concerning efficient control measures. © 2003 Society of Chemical Industry [source] Prenatal RHD gene determination and dosage analysis by PCR: clinical evaluationPRENATAL DIAGNOSIS, Issue 4 2001F.-Y. Chan Abstract Background , Use of the polymerase chain reaction (PCR) for detection of the RHD gene can measure the RHD gene status for unborn babies at risk for hemolytic disease of the newborn (HDN). The occurrence of D gene variants has led to errors in prenatal typing. Previous reports have highlighted the danger of assigning a positive fetus as negative, resulting in intrauterine fetal deaths. Objective , To evaluate the effectiveness of a testing strategy whereby PCR was not only performed to determine the presence/absence of the RHD gene, but also used to assess the D gene copy number (zero, one or two RHD genes) in family studies for at risk pregnancies. Methods , Samples comprising maternal (57) and paternal (42) peripheral blood samples, amniotic fluid (64), and matching cord blood (64) were collected. Rhesus (Rh) serotyping was performed on all blood samples. For RHD genotyping, DNA was extracted from all samples except for 28 cord samples, where only serotyping was performed (total 199 DNA genotyping). RHD gene PCR amplified exon 4 and exon 7 regions of the RHD gene. The dosage of RHD gene was determined by comparing the intensity of the RHD gene to that of the RHCE gene. Results , A total of 197/199 samples showed concordance between exon 4 and exon 7 PCR results. Two discrepant results occurred in one family: the father carried one normal D gene and one D gene variant where PCR was tested to be positive using exon 4 but negative using exon 7. One of a pair of dizygotic twins inherited this abnormal D gene and was mildly affected by HDN. This was correctly identified antenatally and the pregnancy successfully managed. The concordance rate between serotypes and genotypes for 135 blood samples was 100%. Amongst the family groups, 8/14 heterozygous fathers transmitted the D gene and 26/26 homozygous fathers transmitted the D gene to the babies. The concordance rate between RHD genotypes from amniotic fluid and Rh D serotypes from cord blood was also 100%. Conclusion , The present study demonstrates the effectiveness of using PCR in a clinical setting. It verifies the importance of testing more than one region of the gene, and also the need for a testing strategy where both maternal and paternal testing for RHD gene dosages are performed. Copyright © 2001 John Wiley & Sons, Ltd. [source] Genetic and environmental contributions to variation in baboon cranial morphologyAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 1 2010Charles C. Roseman Abstract The development, function, and integration of morphological characteristics are all hypothesized to influence the utility of traits for phylogenetic reconstruction by affecting the way in which morphological characteristics evolve. We use a baboon model to test the hypotheses about phenotypic and quantitative genetic variation of traits in the cranium that bear on a phenotype's propensity to evolve. We test the hypotheses that: 1) individual traits in different functionally and developmentally defined regions of the cranium are differentially environmentally, genetically, and phenotypically variable; 2) genetic covariance with other traits constrains traits in one region of the cranium more than those in others; 3) and regions of the cranium subject to different levels of mechanical strain differ in the magnitude of variation in individual traits. We find that the levels of environmental and genetic variation in individual traits are randomly distributed across regions of the cranium rather than being structured by developmental origin or degree of exposure to strain. Individual traits in the cranial vault tend to be more constrained by covariance with other traits than those in other regions. Traits in regions subject to high degrees of strain during mastication are not any more variable at any level than other traits. If these results are generalizable to other populations, they indicate that there is no reason to suppose that individual traits from any one part of the cranium are intrinsically less useful for reconstructing patterns of evolution than those from any other part. Am J Phys Anthropol 143:1,12, 2010. © 2010 Wiley-Liss, Inc. [source] The role of collegial interaction in continuing professional developmentTHE JOURNAL OF CONTINUING EDUCATION IN THE HEALTH PROFESSIONS, Issue 4 2007Anna R. Gagliardi MLS Abstract Introduction: Many physicians seek information from colleagues over other sources, highlighting the important role of interaction in continuing professional development (CPD). To guide the development of CPD opportunities, this study explored the nature of cancer-related questions faced by general surgeons, and how interaction with colleagues addressed those questions. Methods: This study involved thematic analysis of field notes collected through observation and transcripts of telephone interviews with 20 surgeons, two pathologists, one medical oncologist, and one radiation oncologist affiliated with six community hospitals participating in multidisciplinary cancer conferences by videoconference in one region of Ontario, Canada. Results: Six multidisciplinary cancer conferences (MCCs) were observed between April and September 2006, and 11 interviews were conducted between December 2006 and January 2007. Sharing of clinical experience made possible collective decision making for complex cancer cases. Physicians thought that collegial interaction improved awareness of current evidence, patient satisfaction with treatment plans, appropriate care delivery, and continuity. By comparing proposed treatment with that of the group and gaining exposure to decision making for more cases than they would see in their own practices, physicians developed clinical expertise that could be applied to future cases. Little collegial interaction occurred outside these organized sessions. Discussion: These findings highlight the role of formally coordinated collegial interaction as an important means of CPD for general surgeons. Investment may be required for infrastructure to support such efforts and for release of health professional time for participation. Further research is required to examine direct and indirect outcomes of collegial interaction. [source] FGFR3 protein expression and its relationship to mutation status and prognostic variables in bladder cancer,THE JOURNAL OF PATHOLOGY, Issue 1 2007DC Tomlinson Abstract FGFR3 is frequently activated by mutation in urothelial carcinoma (UC) and represents a potential target for therapy. In multiple myeloma, both over-expression and mutation of FGFR3 contribute to tumour development. To define the population of UC patients who may benefit from FGFR-targeted therapy, we assessed both mutation and receptor over-expression in primary UCs from a population of new patients. Manual or laser capture microdissection was used to isolate pure tumour cell populations. Where present, non-invasive and invasive components in the same section were microdissected. A screen of the region of the highest tumour stage in each sample yielded a mutation frequency of 42%. Mutations comprised 61 single and five double mutations, all in hotspot codons previously identified in UC. There was a significant association of mutation with low tumour grade and stage. Subsequently, non-invasive areas from the 43 tumours with both non-invasive and invasive components were analysed separately; 18 of these had mutation in at least one region, including nine with mutation in all regions examined, eight with mutation in only the non-invasive component and one with different mutations in different regions. Of the eight with mutation in only the non-invasive component, six were predicted to represent a single tumour and two showed morphological dissimilarity of fragments within the block, indicating the possible presence of distinct tumour clones. Immunohistochemistry showed over-expression of FGFR3 protein in many tumours compared to normal bladder and ureteric controls. Increased expression was associated with mutation (85% of mutant tumours showed high-level expression). Overall, 42% of tumours with no detectable mutation showed over-expression, including many muscle-invasive tumours. This may represent a non-mutant subset of tumours in which FGFR3 signalling contributes to the transformed phenotype and which may benefit from FGFR-targeted therapies. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source] Research and Development, Regional Spillovers and the Location of Economic ActivitiesTHE MANCHESTER SCHOOL, Issue 4 2004Alberto Franco Pozzolo I present an endogenous growth model that studies the effects of local inter-industry and intra-industry knowledge spillovers in R&D on the allocation of economic activities between two regions. The equilibrium is the result of a tension between a centripetal force, the cost of transporting goods from one region to the other, and a centrifugal force, the cost increase associated with life in a more crowded area. The presence of local knowledge spillovers, which determines the concentration of the R&D activities within one region, also introduces a further centripetal force that makes a symmetric allocation of the economic activities impossible. The concentration of R&D fosters the equilibrium rate of growth of the economy with respect to the case of no-integration, by increasing the positive effect of local knowledge spillovers. Contrary to the findings of the majority of models in the new economic geography literature, within this framework a reduction in transport costs may be associated with a more even geographical distribution of economic activities. [source] AtMap1: a DNA microarray for genomic deletion mapping in Arabidopsis thalianaTHE PLANT JOURNAL, Issue 6 2008Atsushi J. Nagano Summary We have designed a novel tiling array, AtMap1, for genomic deletion mapping. AtMap1 is a 60-mer oligonucleotide microarray consisting of 42 497 data probes designed from the genomic sequence of Arabidopsis thaliana Col-0. The average probe interval is 2.8 kb. The performance of the AtMap1 array was assessed using the deletion mutants mag2-2, rot3-1 and zig-2. Eight of the probes showed threefold lower signals in mag2-2 than Col-0. Seven of these probes were located in one region on chromosome 3. We considered these adjacent probes to represent one deletion. This deletion was consistent with a reported deleted region. The other probe was located near the end of chromosome 4. A newly identified deletion around the probe was confirmed by PCR. We also detected the responsible deletions for rot3-1 and zig-2. Thus we concluded that the AtMap1 array was sufficiently sensitive to identify a deletion without any a priori knowledge of the deletion. An analysis of the result of hybridization of Ler and previously reported polymorphism data revealed that the signal decrease tended to depend on the overlap size of sequence polymorphisms. Mutation mapping is time-consuming, laborious and costly. The AtMap1 array removes these limitations. [source] A retrospective study of anaesthetic caseload of Specialist Registrars following the introduction of new working patterns in the Wessex region,ANAESTHESIA, Issue 3 2009S. Al-Rawi Summary The impact of implementing the European Working Time Directive (EWTD) and the consequent reduction in hours of work has led to concerns about training. This retrospective study compared total caseload, obstetric caseload, out-of-hours caseload and supervision levels of trainee anaesthetists in one region of the UK (Wessex) before and after the implementation of EWTD compliant rotas. Anaesthetic trainee logbooks submitted at the annual Record of In-Training Assessment were compared between the years 1999 and 2006. The logbook data was divided into two groups, group A (13-h shift) and group B (24-h on-call rota). There was no difference in total caseload, obstetric caseload or supervision. Out-of-hours caseload was greater in group A (p < 0.01). [source] Identification of a novel susceptibility locus for juvenile idiopathic arthritis by genome-wide association analysisARTHRITIS & RHEUMATISM, Issue 1 2009Anne Hinks Objective Juvenile idiopathic arthritis (JIA) is a chronic rheumatic disease of childhood. Two well-established genetic factors known to contribute to JIA susceptibility, HLA and PTPN22, account for less than half of the genetic susceptibility to disease; therefore, additional genetic factors have yet to be identified. The purpose of this study was to perform a systematic search of the genome to identify novel susceptibility loci for JIA. Methods A genome-wide association study using Affymetrix GeneChip 100K arrays was performed in a discovery cohort (279 cases and 184 controls). Single-nucleotide polymorphisms (SNPs) showing the most significant differences between cases and controls were then genotyped in a validation sample of cases (n = 321) and controls, combined with control data from the 1958 UK birth cohort (n = 2,024). In one region in which association was confirmed, fine-mapping was performed (654 cases and 1,847 controls). Results Of the 112 SNPs that were significantly associated with JIA in the discovery cohort, 6 SNPs were associated with JIA in the independent validation cohort. The most strongly associated SNP mapped to the HLA region, while the second strongest association was with a SNP within the VTCN1 gene. Fine-mapping of that gene was performed, and 10 SNPs were found to be associated with JIA. Conclusion This study is the first to successfully apply a SNP-based genome-wide association approach to the investigation of JIA. The replicated association with markers in the VTCN1 gene defined an additional susceptibility locus for JIA and implicates a novel pathway in the pathogenesis of this chronic disease of childhood. [source] The Cnidarian and the Canon: the role of Wnt/,-catenin signaling in the evolution of metazoan embryosBIOESSAYS, Issue 5 2004Alex Primus In a recent publication, Wikramanayake and colleagues have implicated the canonical Wnt/,-catenin signaling pathway as a mediator of axial polarity and germ-layer specification in embryos of the cnidarian Nematostella.1 In this anthozoan, ,-catenin is localized in nuclei of blastomeres in one region of the 16- to 32-cell embryo whose descendants subsequently form the entoderm of the embryo. They claim that the pattern of nuclear localization is significant for two reasons: (1) when nuclear localization of ,-catenin was inhibited, gastrulation does not occur, and (2) when localization of ,-catenin took place in all cells of the pregastrula embryo, the number of entodermal cells increases. Since the Wnt/,-catenin signaling pathway also plays a role in establishing axial polarity and specifying endoderm and mesoderm in a number of bilaterians,2,6 Wikramanayake et al. imply that this developmental mechanism is an evolutionary inheritance from a radially symmetrical ancestor. Some of the gaps in the current evidence, which must be filled to evaluate their interpretation, are discussed. BioEssays 26:474,478, 2004. © 2004 Wiley Periodicals, Inc. [source] An in ovo chicken model to study the systemic and localized teratogenic effects of valproic acidBIRTH DEFECTS RESEARCH, Issue 4 2002Amy I. Whitsel Background The antiepileptic valproic acid (VPA) is a teratogen whose embryopathic mechanism(s) remain uncertain. Elucidating potential cellular and molecular effects of VPA is complicated by systemic application paradigms. We developed an in ovo model to reproduce the teratogenic effects of VPA and a localized VPA application procedure to determine whether VPA can selectively effect abnormal development in one region of the embryo. Methods VPA was applied topically to chicken embryos in ovo at different embryonic stages. Embryos were later evaluated for gross and skeletal anomalies. Pax-2 and Pax-6 protein expression in the developing eye was also evaluated because VPA-induced eye anomalies are similar to those seen by the disruption of Pax-2 and Pax-6. For localized application, a thin sheet of the synthetic polymer Elvax was impregnated with VPA. A small piece of the VPA-impregnated polymer was applied directly to the presumptive wing bud region in Stage 10,17 embryos. Embryos were examined for gross and skeletal anomalies. Sham controls were employed for all experiments. Results Chicken embryos exposed to VPA in ovo demonstrated increased mortality, growth delay and anomalies similar to ones previously seen in humans: neural tube, cardiovascular, craniofacial, limb and skeletal. Pax-2 and Pax-6 protein expression was qualitatively diminished in the eye. Localized wing bud VPA exposure caused structural abnormalities in the developing wing in the absence of other anomalies in the embryos. These wing defects were similar to those observed after topical whole-embryo VPA application. Conclusions These results indicate that at least one mechanism for the teratogenicity of VPA involves a direct effect on developing tissue. The nature of the abnormalities observed implies that this effect may be mediated by disruption of genes that regulate pattern formation. Teratology 66:153,163, 2002. © 2002 Wiley-Liss, Inc. [source] Radial secondary growth and formation of successive cambia and their products in Ipomoea hederifolia L. (Convolvulaceae)BOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2008KISHORE S. RAJPUT Ipomoea hederifolia stems increase in thickness using a combination of different types of cambial variant, such as the discontinuous concentric rings of cambia, the development of included phloem, the reverse orientation of discontinuous cambial segments, the internal phloem, the formation of secondary xylem and phloem from the internal cambium, and differentiation of cork in the pith. After primary growth, the first ring of cambium arises between the external primary phloem and primary xylem, producing secondary phloem centrifugally and secondary xylem centripetally. The stem becomes lobed, flat, undulating, or irregular in shape as a result of the formation of both discontinuous and continuous concentric rings of cambia. As the formation of secondary xylem is greater in one region than in another, this results in the formation of a grooved stem. Successive cambia formed after the first ring are of two distinct functional types: (1) functionally normal successive cambia that divide to form secondary xylem centripetally and secondary phloem centrifugally, like other dicotyledons that show successive rings, and (2) abnormal cambia with reverse orientation. The former type of successive rings originates from the parenchyma cells located outside the phloem produced by previous cambium. The latter type of cambium develops from the conjunctive tissue located at the base of the secondary xylem formed by functionally normal cambia. This cambium is functionally inverted, producing secondary xylem centrifugally and secondary phloem centripetally. In later secondary growth, xylem parenchyma situated deep inside the secondary xylem undergoes de-differentiation, and re-differentiates into included phloem islands in secondary xylem. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158, 30,40. [source] | ||||||||||||||||||||||||||||||||||