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Selected AbstractsRegional Planning in Queensland's Rangelands: Challenges and Prospects for Biodiversity ConservationGEOGRAPHICAL RESEARCH, Issue 1 2007CLIVE A. MCALPINE Abstract In Australia, the Commonwealth and State governments are increasingly devolving natural resource management (NRM) responsibilities to regional bodies. This move has led to the development of regional NRM plans. Native vegetation and biodiversity conservation, along with soil, pasture and water resources, are key components of the regional NRM plans in Queensland's extensive rangelands. This paper outlines and applies a set of criteria for evaluating the native vegetation and biodiversity content of accredited regional NRM plans for Queensland's rangelands. The evaluation showed considerable variation in the comprehensiveness of the information and knowledge base and management action targets among plans, including the poor articulation of impacts of excessive grazing pressure on biodiversity. The NRM plans lacked effective integration of natural resource, native vegetation and biodiversity conservation targets and actions. Several regions had too many biodiversity targets, many of which were poorly integrated. This is symptomatic of a limited understanding of rangelands as ecological systems and the lack of an integrated planning framework. We conclude regional NRM planning is not a ,silver bullet' for biodiversity conservation in the rangelands, but rather, it is the beginning of a long road to address complex, multi-scale problems at a regional level. [source] Spectroscopic characterization of the conformational states of the bis(trifluoromethanesulfonyl)imide anion (TFSI,)JOURNAL OF RAMAN SPECTROSCOPY, Issue 8 2005M. Herstedt Abstract Ab initio calculations were combined with infrared and Raman studies to distinguish spectroscopically the two conformers of the bis(trifluoromethanesulfonyl)imide anion, (TFSI,). Spectra of crystalline LiTFSI complexes with organic ligands, where the anion adopts a known conformational state, are presented to confirm the calculated spectra. Several regions are identified where either the infrared or the Raman spectra contain separate bands for the two conformers. The conformational equilibrium between the transoid and cisoid rotamers is then illustrated from the infrared spectra of solutions of LiTFSI in aprotic solvents. The transoid form is found to be more stable than the cisoid form by about 2.2 kJ mol,1, in good agreement with the present and earlier theoretical predictions. It is also shown that the IR and Raman spectral changes coming from conformational isomerism have to be carefully distinguished from those due to ionic interactions. Copyright © 2005 John Wiley & Sons, Ltd. [source] Existence of a genetic risk factor on chromosome 5q in Italian Coeliac Disease familiesANNALS OF HUMAN GENETICS, Issue 1 2001L. GRECO Coeliac disease (CD) is a malabsorptive disorder of the small intestine resulting from ingestion of gluten. The HLA risk factors involved in CD are well known but do not explain the whole genetic susceptibility. Several regions of potential linkage on chromosomes 3q, 5q, 10q, 11q, 15q and 19q have already been reported in the literature. These six regions were analyzed with the Maximum Lod Score method on a dense set of markers. A new sample of 89 Italian sibpairs was available for study. There was no evidence for linkage for any of the regions tested, except for chromosome 5q. For this region, our data, as well as a sample of 93 sibpairs from our first genome screen (Greco et al. 1998), are compatible with the presence of a risk factor for CD with a moderate effect. [source] Regional heterogeneity in the developing palate: morphological and molecular evidence for normal and abnormal palatogenesisCONGENITAL ANOMALIES, Issue 2 2006Junko Okano ABSTRACT Development of the mammalian secondary palate involves the growth, elevation, medial elongation and midline fusion of palatal shelves. Recent morphological and molecular studies on palatogenesis suggest that the developing palate is not a homogeneous organ but each part may behave differently during organogenesis. Especially, some key molecules involved in palate development have been shown to exhibit heterogeneous patterns of expression in the palatal tissue. Therefore it seems necessary to recognize the regional heterogeneity of the developing palate along the dorsoventral and anteroposterior axes when analyzing the mechanisms of normal and abnormal morphogenesis. Based on recent studies, we discuss the issue of the regional heterogeneity in the fetal palate and propose a principle that divides the fetal palate into several regions from the morphological and molecular standpoint. [source] Bog Iron Ores and their Potential Role in Arsenic Dynamics: An Overview and a "Paleo Example"ENGINEERING IN LIFE SCIENCES (ELECTRONIC), Issue 6 2008A. Banning Abstract Bog iron ores (BIOs), i.e. terrestrial accumulations of iron (Fe) minerals forming within the zone of groundwater oscillation, have been described in several regions in Germany and other countries. Since BIOs are composed of a variety of Fe minerals, primarily amorphous Fe hydroxides, they are likely to have an influence on the arsenic (As) dynamics of an area, as these minerals represent important natural As sources and sinks. In this study, mineralogical research results (XRD, microscopy) of altered BIOs of Tertiary age ("paleo" BIOs or PBIOs), occurring within Cretaceous sands in an area of North Rhine-Westphalia, are briefly presented. Genesis and mineralogical evolution of the categorized five different types of PBIOs, along with hydrogeochemical data from the literature, are discussed and compared to studies describing Holocene BIOs from other areas. In doing so, striking similarities (depositional environment, substratum, Fe source and its transport, geochemical evolution, and mineralogy) became evident. Differences in mineralogical and chemical composition can be attributed to the longer period of oxidation that the PBIOs have undergone (Fe hydroxide "aging"). This process is still ongoing (most of the groundwaters in the area plot in the goethite stability field) and leads to a higher stability of the Fe phases and thus, a stronger As retention. The known impact of the PBIOs on the As budget of the study area (they represent the source for elevated As concentrations in soils) can be transferred to more recent environments fostering BIO formation. These are likely to be even more important As sinks , and sources , as they contain higher Fe concentrations, higher shares of potentially mobile As and highly variable redox conditions which might lead to an As output from the BIOs into groundwater, soils and plants. Therefore, BIOs and their potential role in As behaviour are not only of scientific, but also of public interest. [source] Genome sequence of Desulfobacterium autotrophicum HRM2, a marine sulfate reducer oxidizing organic carbon completely to carbon dioxideENVIRONMENTAL MICROBIOLOGY, Issue 5 2009Axel W. Strittmatter Summary Sulfate-reducing bacteria (SRB) belonging to the metabolically versatile Desulfobacteriaceae are abundant in marine sediments and contribute to the global carbon cycle by complete oxidation of organic compounds. Desulfobacterium autotrophicum HRM2 is the first member of this ecophysiologically important group with a now available genome sequence. With 5.6 megabasepairs (Mbp) the genome of Db. autotrophicum HRM2 is about 2 Mbp larger than the sequenced genomes of other sulfate reducers (SRB). A high number of genome plasticity elements (> 100 transposon-related genes), several regions of GC discontinuity and a high number of repetitive elements (132 paralogous genes Mbp,1) point to a different genome evolution when comparing with Desulfovibrio spp. The metabolic versatility of Db. autotrophicum HRM2 is reflected in the presence of genes for the degradation of a variety of organic compounds including long-chain fatty acids and for the Wood,Ljungdahl pathway, which enables the organism to completely oxidize acetyl-CoA to CO2 but also to grow chemolithoautotrophically. The presence of more than 250 proteins of the sensory/regulatory protein families should enable Db. autotrophicum HRM2 to efficiently adapt to changing environmental conditions. Genes encoding periplasmic or cytoplasmic hydrogenases and formate dehydrogenases have been detected as well as genes for the transmembrane TpII- c3, Hme and Rnf complexes. Genes for subunits A, B, C and D as well as for the proposed novel subunits L and F of the heterodisulfide reductases are present. This enzyme is involved in energy conservation in methanoarchaea and it is speculated that it exhibits a similar function in the process of dissimilatory sulfate reduction in Db. autotrophicum HRM2. [source] Do neurons have a reserve of sodium channels for the generation of action potentials?EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 1 2000A study on acutely isolated CA1 neurons from the guinea-pig hippocampus Abstract The density of voltage-gated sodium channels is high in several regions of the neuronal membrane. It is unclear if this density of channels represents a reserve for the neuron, or if it fulfils a special role in action potential firing. This problem was addressed by studying sodium currents and action potentials in acutely isolated hippocampal CA1 neurons whose number of active sodium channels was acutely changed by applying the sodium channel blocker tetrodotoxin (TTX) at different concentrations. The results show that more than a third of the sodium channels can fail without affecting the single action potential. Thus, the neurons have a remarkable surplus of sodium channels. The surplus, however, is necessary for repetitive action potential firing, as every decrease in the fraction of sodium channels reduces the maximal frequency of action potentials that can be generated by the neuron. [source] Comparative genome analysis of a Saccharomyces cerevisiae wine strainFEMS YEAST RESEARCH, Issue 7 2008Anthony R. Borneman Abstract Many industrial strains of Saccharomyces cerevisiae have been selected primarily for their ability to convert sugars into ethanol efficiently despite exposure to a variety of stresses. To begin investigation of the genetic basis of phenotypic variation in industrial strains of S. cerevisiae, we have sequenced the genome of a wine yeast, AWRI1631, and have compared this sequence with both the laboratory strain S288c and the human pathogenic isolate YJM789. AWRI1631 was found to be substantially different from S288c and YJM789, especially at the level of single-nucleotide polymorphisms, which were present, on average, every 150 bp between all three strains. In addition, there were major differences in the arrangement and number of Ty elements between the strains, as well as several regions of DNA that were specific to AWRI1631 and that were predicted to encode proteins that are unique to this industrial strain. [source] A metapopulation perspective for salmon and other anadromous fishFISH AND FISHERIES, Issue 4 2007Nicolas Schtickzelle Abstract Salmonids are an important component of biodiversity, culture and economy in several regions, particularly the North Pacific Rim. Given this importance, they have been intensively studied for about a century, and the pioneering scientists recognized the critical link between population structure and conservation. Spatial structure is indeed of prime importance for salmon conservation and management. At first glance, the essence of the metapopulation concept, i.e. a population of populations, widely used on other organisms like butterflies, seems to be particularly relevant to salmon, and more generally to anadromous fish. Nevertheless, the concept is rarely used, and barely tested. Here, we present a metapopulation perspective for anadromous fish, assessing in terms of processes rather than of patterns the set of necessary conditions for metapopulation dynamics to exist. Salmon, and particularly sockeye salmon in Alaska, are used as an illustrative case study. A review of life history traits indicates that the three basic conditions are likely to be fulfilled by anadromous salmon: (i) the spawning habitat is discrete and populations are spatially separated by unsuitable habitat; (ii) some asynchrony is present in the dynamics of more or less distant populations and (iii) dispersal links populations because some salmon stray from their natal population. The implications of some peculiarities of salmon life history traits, unusual in classical metapopulations, are also discussed. Deeper understanding of the population structure of anadromous fish will be advanced by future studies on specific topics: (i) criteria must be defined for the delineation of suitable habitats that are based on features of the biotope and not on the presence of fish; (ii) the collection of long-term data and the development of improved methods to determine age structure are essential for correctly estimating levels of asynchrony between populations and (iii) several key aspects of dispersal are still poorly understood and need to be examined in detail: the spatial and temporal scales of dispersal movements, the origin and destination populations instead of simple straying rates, and the relative reproductive success of immigrants and residents. [source] MRI-based evaluation of locus and extent of neurotoxic lesions in monkeys ,HIPPOCAMPUS, Issue 4 2001e Málková Abstract To minimize the variability in the extent of lesions made by injections of the excitotoxin ibotenic acid in rhesus monkeys, we developed and validated an MRI-based method to determine the efficacy of the injections soon after surgery. T2-weighted MR images were obtained 6,11 days after surgery from 17 brain hemispheres of monkeys that had received bilateral lesions of either the hippocampal formation (HF), perirhinal cortex, or parahippocampal cortex. The extent of lesion estimated from the hypersignal that appeared in and outside of the targeted area on these MR images was compared with the extent of damage assessed histologically after survival periods ranging from 120,370 days. Highly significant correlations (r values between 0.85,0.99) were found between these two measures for several regions in the medial temporal lobe. Based on this finding, lack of hypersignal in the targeted area of some Ss was followed by successful reinjection of the neurotoxin to create more complete cell loss prior to the postoperative phase of the study. We also assessed the relationship between a postoperative reduction in HF volume, measured from T1-weighted MR images, and the extent of damage determined histologically in 14 hemispheres of monkeys with bilateral excitotoxic HF lesions. The HF volume decreases sharply after surgery until 40,50 days postoperatively, after which there is only a minor further decrease. Based on this finding, we obtained T1-weighted MR images at least 44 days but in most cases close to 1 year after surgery. A highly significant positive correlation (r = 0.95, P < 0.001) was found between neuronal damage and volume reduction, with nearly complete neuronal damage (96,99%) corresponding to a volume reduction of 68,79%. These MRI-based methods thus provide an accurate in vivo evaluation of the locus and extent of neurotoxic lesions. Application of these methods can ensure that each animal in the experiment is used effectively. Hippocampus 2001;11:361,370. Published 2001 Wiley-Liss, Inc. [source] Auditory orienting and inhibition of return in mild traumatic brain injury: A FMRI studyHUMAN BRAIN MAPPING, Issue 12 2009Andrew R. Mayer Abstract The semiacute phase of mild traumatic brain injury (mTBI) is associated with deficits in the cognitive domains of attention, memory, and executive function, which previous work suggests may be related to a specific deficit in disengaging attentional focus. However, to date, there have only been a few studies that have employed dynamic imaging techniques to investigate the potential neurological basis of these cognitive deficits during the semiacute stage of injury. Therefore, event-related functional magnetic resonance imaging was used to investigate the neurological correlates of attentional dysfunction in a clinically homogeneous sample of 16 patients with mTBI during the semiacute phase of injury (<3 weeks). Behaviorally, patients with mTBI exhibited deficits in disengaging and reorienting auditory attention following invalid cues as well as a failure to inhibit attentional allocation to a cued spatial location compared to a group of matched controls. Accordingly, patients with mTBI also exhibited hypoactivation within thalamus, striatum, midbrain nuclei, and cerebellum across all trials as well as hypoactivation in the right posterior parietal cortex, presupplementary motor area, bilateral frontal eye fields, and right ventrolateral prefrontal cortex during attentional disengagement. Finally, the hemodynamic response within several regions of the attentional network predicted response times better for controls than for patients with mTBI. These objective neurological findings represent a potential biomarker for the behavioral deficits in spatial attention that characterize the initial recovery phase of mTBI. Hum Brain Mapp, 2009. © 2009 Wiley-Liss, Inc. [source] fMRI changes in relapsing-remitting multiple sclerosis patients complaining of fatigue after IFN,-1a injectionHUMAN BRAIN MAPPING, Issue 5 2007Maria A. Rocca Abstract If fatigue in multiple sclerosis (MS) is related to an abnormal activation of the sensorimotor brain network, the activity of such a network should vary with varying fatigue. We studied 22 patients treated with interferon beta 1a (IFN,-1a; Avonex, Biogen, Cambridge, MA) with no fatigue (10) and with reversible fatigue (12). fMRI examinations were performed: 1) the same day of IFN,-1a injection (no fatigue; entry), 2) the day after IFN,-1a injection (fatigue; time 1), and 3) 4 days after IFN,-1a injection (no fatigue; time 2). Patients performed a simple motor task with the right, clinically unaffected hand. At time 1, compared with entry and time 2, MS patients with reversible fatigue showed an increased activation of the thalamus bilaterally. In MS patients without fatigue thalamus was more activated at entry than at time 1. In both groups at entry the primary SMC and the SMA were more activated than at times 1 and 2. At entry and time 1, when compared to patients with reversible fatigue, those without showed increased activations of the SII. Conversely, patients with reversible fatigue had increased activations of the thalamus and of several regions of the frontal lobes. An abnormal recruitment of the fronto-thalamic circuitry is associated with IFN,-1a-induced fatigue in MS patients. Hum Brain Mapp, 2007. © 2006 Wiley-Liss, Inc. [source] Causal factors for spatial variation in long-term phenological trends in Ginkgo biloba L. in JapanINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 9 2010Kazuho Matsumoto Abstract Distinct plant phenological changes caused by increasing temperature have been reported in several regions. However, spatial patterns in long-term phenological trends and their causal factors have not been fully examined. Attempts were made to address these issues using a long-term (1961,2000) phenological dataset (budding and leaf fall dates) for Ginkgo biloba L. from 60 meteorological stations in Japan. Although many stations indicated earlier budding and delayed leaf fall, there were large differences among stations. First, the author tried to understand the spatial variation patterns of the long-term phenological trends relative to geography. However, there was no significant relationship between phenological trends and geographical variables: latitude, longitude, and altitude, with the exception of a negative relationship between the trend of leaf fall date and latitude. Second, relationships between phenological trends, long-term trends in air temperature, and phenological sensitivity of Ginkgo to variations in air temperature were investigated as direct causal factors for spatial variations in phenological trends. With respect to the air temperature trend, a negative relationship was found with the budding trend, but there was no obvious relationship with the leaf fall trend. On the other hand, the spatial variability of the phenological sensitivity to temperature was relatively large and displayed a significant linear relationship with trends in budding and leaf fall. Where trees had higher sensitivity to temperature, they showed earlier budding and delayed leaf fall. The results obtained from multiple linear regressions indicated that the spatial variations in phenological trends were dependent more on phenological sensitivity to air temperature than temperature trends. Copyright © 2009 Royal Meteorological Society [source] Winter snow depth variability over northern Eurasia in relation to recent atmospheric circulation changesINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 13 2007V. Popova Abstract Mean snow depth time-series for February (1936,2001) over northern Eurasia (incl. Norway, Finland and the former USSR), interpolated into 5 × 5° grid points, are studied using empirical orthogonal function (EOF) analysis. First, five statistically significant rotated PCs are correlated to Northern Hemisphere (NH) teleconnection patterns at the 700 hPa height: North Atlantic Oscillation (NAO), Polar-Eurasia (Pol), Pacific-North American (PNA), West Pacific (WP), and Scandinavia (Scand). The impact of the NH circulation modes on snow depth variations is evaluated using the multiple stepwise backward regression (MSBR). Analyses of the snow depth PCs indicate that within the northern Eurasia territory, there are several regions with snow accumulation, respondent to certain circulation modes. PC1 describes low-frequency snow depth variation to the north from 55 to 60°N between the White Sea and the Lena river basin, and is positively correlated with NAO and negatively,with Scand. MSBR shows that in 1951,1974 the leading role in snow depth variability belongs to Scand. After 1975, Scand has passed over the leading role to NAO. Scand and NAO are also responsible for the surface air temperature changes over the northern Eurasia. Snow depth PC1 and wintertime temperature are closely related to each other. PC2 describes quasi-decadal snow depth variability over eastern Europe and is negatively correlated with NAO. For the Baltic and White Sea coasts, Fennoscandia, and the center of the East European plain, decrease of snow accumulation, related to a positive NAO phase, seems to be caused by mild winters. For the southwestern and central regions of eastern Europe, negative snow depth anomalies could also be caused by decrease of precipitation associated with the eastward shift of cyclone tracks related to the positive NAO phase. Two regions, where snow depth variations are described by PC1 and PC2, respectively, reveal the border between the opposite recent tendencies of snow accumulation. Copyright © 2007 Royal Meteorological Society [source] Impact of Water Stress on Maize Grown Off-Season in a Subtropical EnvironmentJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 4 2007C. M. T. Soler Abstract During the last decade, the production of off-season maize has increased in several regions of Brazil. Growing maize during this season, with sowing from January through April, imposes several climatic risks that can impact crop yield. This is mainly caused by the high variability of precipitation and the probability of frost during the reproduction phases. High production risks are also partially due to the use of cultivars that are not adapted to the local environmental conditions. The goal of this study was to evaluate crop growth and development and associated yield, yield components and water use efficiency (WUE) for maize hybrids with different maturity ratings grown off-season in a subtropical environment under both rainfed and irrigated conditions. Three experiments were conducted in 2001 and 2002 in Piracicaba, state of São Paulo, Brazil with four hybrids of different maturity duration, AG9010 (very short season), DAS CO32 and Exceler (short season) and DKB 333B (normal season). Leaf area index (LAI), plant height and dry matter were measured approximately every 18 days. Under rainfed conditions, the soil water content in the deeper layers was reduced, suggesting that the extension of the roots into these layers was a response to soil water limitations. On average, WUE varied from 1.45 kg m,3 under rainfed conditions to 1.69 kg m,3 under irrigated conditions during 2001. The average yield varied from 4209 kg ha,1 for the hybrids grown under rainfed conditions to 5594 kg ha,1 under irrigated conditions during 2001. Yield reductions under rainfed conditions were affected by the genotype. For the hybrid DKB 333B with a normal maturity, yield was reduced by 25.6 % while the short maturity hybrid Exceler was the least impacted by soil water limitations with a yield reduction of only 8.4 %. To decrease the risk of yield loss, the application of supplemental irrigation should be considered by local farmers, provided that this practice is not restricted by either economic considerations or the availability of sufficient water resources. [source] The anatomy of language: contributions from functional neuroimagingJOURNAL OF ANATOMY, Issue 3 2000CATHY J. PRICE This article illustrates how functional neuroimaging can be used to test the validity of neurological and cognitive models of language. Three models of language are described: the 19th Century neurological model which describes both the anatomy and cognitive components of auditory and visual word processing, and 2 20th Century cognitive models that are not constrained by anatomy but emphasise 2 different routes to reading that are not present in the neurological model. A series of functional imaging studies are then presented which show that, as predicted by the 19th Century neurologists, auditory and visual word repetition engage the left posterior superior temporal and posterior inferior frontal cortices. More specifically, the roles Wernicke and Broca assigned to these regions lie respectively in the posterior superior temporal sulcus and the anterior insula. In addition, a region in the left posterior inferior temporal cortex is activated for word retrieval, thereby providing a second route to reading, as predicted by the 20th Century cognitive models. This region and its function may have been missed by the 19th Century neurologists because selective damage is rare. The angular gyrus, previously linked to the visual word form system, is shown to be part of a distributed semantic system that can be accessed by objects and faces as well as speech. Other components of the semantic system include several regions in the inferior and middle temporal lobes. From these functional imaging results, a new anatomically constrained model of word processing is proposed which reconciles the anatomical ambitions of the 19th Century neurologists and the cognitive finesse of the 20th Century cognitive models. The review focuses on single word processing and does not attempt to discuss how words are combined to generate sentences or how several languages are learned and interchanged. Progress in unravelling these and other related issues will depend on the integration of behavioural, computational and neurophysiological approaches, including neuroimaging. [source] The effects of plant structure on the spatial and microspatial distribution of a bromeliad-living jumping spider (Salticidae)JOURNAL OF ANIMAL ECOLOGY, Issue 1 2005GUSTAVO Q. ROMERO Summary 1In several regions of South America, the neotropical jumping spider Psecas chapoda inhabits and reproduces strictly on the bromeliad Bromelia balansae. Previous studies reported that this spider is more frequent on bromeliads in grasslands than on those growing in forests, and on larger plants, but only when the bromeliads are without inflorescence. Upon blooming, B. balansae fold their leaves back, thereby changing the plant architecture from a tri-dimensional to a bi-dimensional flattened shape, and our hypothesis is that this alteration affects the spider's habitat-selection decisions. 2In the present study, we examined experimentally the effects of inflorescence, plant size and blockade of the axil of the leaves (spider shelters) of forest bromeliads on the colonization of a bromeliad by P. chapoda. By using sticky traps, we also compared prey availability in grassland and forest. 3Plants with simulated inflorescence were colonized at a lower frequency than those without inflorescence simulation. Grassland bromeliads in which the rosettes were blocked with dry leaves were colonized less frequently than open bromeliads, whereas forest bromeliads from which dry leaves had been removed were not colonized. Spiders generally abandoned bromeliads in which three-quarters of the length of the leaves had been removed, although females with eggsacs remained on these plants. Prey availability (biomass and number) was up to 18 fold higher in the grassland than in the forest. These results suggest that microhabitat structure and prey availability shape the spatial distribution of P. chapoda populations. 4Our findings suggest that Psecas chapoda can evaluate, in fine detail, the physical state of its microhabitat, and this unusual spider,plant association is readily destabilized by changes in the microhabitat (i.e., it is strictly dependent on the size and morphology of the host plant). This study is one of the few to report a strict association between a spider species and its host plant, and also one of the few to examine the effects of habitat and microhabitat structure on the spatial distribution of active hunters on plants. [source] Evaluating the power of monitoring plot designs for detecting long-term trends in the numbers of common guillemotsJOURNAL OF APPLIED ECOLOGY, Issue 3 2006MICHELLE SIMS Summary 1In recent years concerns have been raised regarding the status of the common guillemot Uria aalge in the UK. Numbers have declined in several regions, highlighting the need for continued monitoring of this internationally important population. However, the extent to which the current monitoring scheme is capable of detecting declines and options for improving efficiency has received little attention. 2We investigated the power of different monitoring design options for detecting long-term trends in abundance at a colony of guillemots. The ability to detect trends in abundance was reduced by the large temporal and spatial variability in colony attendance. Taking a linear mixed model approach, we obtained details on the sources and sizes of the variance components using count data collected from monitoring plots on the Isle of May, Scotland, and assessed how best to allocate sampling effort in the light of the count variability structure. 3Our results indicated that trend detection will be improved by counting birds in more plots rather than by increasing the number of counts at existing plots. 4The revisit pattern of counts at the monitoring plots during the seasonal counting period had little effect on trend detection power. However, given the practical issues associated with counting guillemots, alternative revisit patterns to the current approach are preferred. 5For a fixed number of visits per plot, power is strongly influenced by the choice of revisit design if the day-to-day variation in colony attendance is increased. 6Synthesis and applications. Aspects of the UK seabird monitoring scheme can be improved. Changes to the allocation of sampling effort and the plot-revisit pattern will improve both the statistical power to detect long-term trends and the efficiency of conducting the survey. We stress the importance of considering the structure and magnitude of the count variation in a power analysis because judicious design decisions depend on the relative magnitude of these variance components. [source] Ecological biogeography of North American mammals: species density and ecological structure in relation to environmental gradientsJOURNAL OF BIOGEOGRAPHY, Issue 6 2000Catherine Badgley Abstract Aim, To evaluate the relationship of climate and physiography to species density and ecological diversity of North American mammals. Location, North America, including Mexico and Central America. Methods, Species density, size structure and trophic structure of mammalian faunas and nine environmental variables were documented for quadrats covering the entire continent. Spatial autocorrelation of species density and the environmental variables illustrated differences in their spatial structure at the continental scale. We used principal component analysis to reduce the dimensionality of the climatic variables, linear multiple regression to determine which environmental variables best predict species density for the continent and several regions of the continent, and canonical ordination to evaluate how well the environmental variables predict ecological structure of mammalian faunas over North America. Results, In the best regression model, five environmental variables, representing seasonal extremes of temperature, annual energy and moisture, and elevation, predicted 88% of the variation in species density for the whole continent. Among different regions of North America, the environmental variables that predicted species density vary. Changes in the size and trophic structure of mammalian faunas accompany changes in species density. Redundancy analysis demonstrated that environmental variables representing winter temperature, frostfree period, potential and actual evapotranspiration, and elevation account for 77% of the variation in ecological structure. Main conclusions, The latitudinal gradient in mammalian species density is strong, but most of it is explained by variation in the environmental variables. Each ecological category peaks in species richness under particular environmental conditions. The changes of greatest magnitude involve the smallest size categories (< 10 g, 11,100 g), aerial insectivores and frugivores. Species in these categories, mostly bats, increase along a gradient of decreasing winter temperature and increasing annual moisture and frostfree period, trends correlated with latitude. At the opposite end of this gradient, species in the largest size category (101,1000 kg) increase in frequency. Species in size categories 3 (101,1000 g), 5 (11,100 kg) and 6 (101,1000 kg), herbivores, and granivores increase along a longitudinal gradient of increasing annual potential evapotranspiration and elevation. Much of the spatial pattern is consistent with ecological sorting of species ranges along environmental gradients, but differential rates of speciation and extinction also may have shaped the ecological diversity of extant North American mammals. [source] Mid-Holocene and glacial-maximum vegetation geography of the northern continents and AfricaJOURNAL OF BIOGEOGRAPHY, Issue 3 2000I. Colin Prentice Abstract BIOME 6000 is an international project to map vegetation globally at mid-Holocene (6000 14C yr bp) and last glacial maximum (LGM, 18,000 14C yr bp), with a view to evaluating coupled climate-biosphere model results. Primary palaeoecological data are assigned to biomes using an explicit algorithm based on plant functional types. This paper introduces the second Special Feature on BIOME 6000. Site-based global biome maps are shown with data from North America, Eurasia (except South and Southeast Asia) and Africa at both time periods. A map based on surface samples shows the method's skill in reconstructing present-day biomes. Cold and dry conditions at LGM favoured extensive tundra and steppe. These biomes intergraded in northern Eurasia. Northern hemisphere forest biomes were displaced southward. Boreal evergreen forests (taiga) and temperate deciduous forests were fragmented, while European and East Asian steppes were greatly extended. Tropical moist forests (i.e. tropical rain forest and tropical seasonal forest) in Africa were reduced. In south-western North America, desert and steppe were replaced by open conifer woodland, opposite to the general arid trend but consistent with modelled southward displacement of the jet stream. The Arctic forest limit was shifted slighly north at 6000 14C yr bp in some sectors, but not in all. Northern temperate forest zones were generally shifted greater distances north. Warmer winters as well as summers in several regions are required to explain these shifts. Temperate deciduous forests in Europe were greatly extended, into the Mediterranean region as well as to the north. Steppe encroached on forest biomes in interior North America, but not in central Asia. Enhanced monsoons extended forest biomes in China inland and Sahelian vegetation into the Sahara while the African tropical rain forest was also reduced, consistent with a modelled northward shift of the ITCZ and a more seasonal climate in the equatorial zone. Palaeobiome maps show the outcome of separate, independent migrations of plant taxa in response to climate change. The average composition of biomes at LGM was often markedly different from today. Refugia for the temperate deciduous and tropical rain forest biomes may have existed offshore at LGM, but their characteristic taxa also persisted as components of other biomes. Examples include temperate deciduous trees that survived in cool mixed forest in eastern Europe, and tropical evergreen trees that survived in tropical seasonal forest in Africa. The sequence of biome shifts during a glacial-interglacial cycle may help account for some disjunct distributions of plant taxa. For example, the now-arid Saharan mountains may have linked Mediterranean and African tropical montane floras during enhanced monsoon regimes. Major changes in physical land-surface conditions, shown by the palaeobiome data, have implications for the global climate. The data can be used directly to evaluate the output of coupled atmosphere-biosphere models. The data could also be objectively generalized to yield realistic gridded land-surface maps, for use in sensitivity experiments with atmospheric models. Recent analyses of vegetation-climate feedbacks have focused on the hypothesized positive feedback effects of climate-induced vegetation changes in the Sahara/Sahel region and the Arctic during the mid-Holocene. However, a far wider spectrum of interactions potentially exists and could be investigated, using these data, both for 6000 14C yr bp and for the LGM. [source] Bone Mineral Response to a 7-Month Randomized Controlled, School-Based Jumping Intervention in 121 Prepubertal Boys: Associations With Ethnicity and Body Mass Index,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 5 2002K. J. Mackelvie Abstract We examined the effects of a 7-month jumping intervention (10 minutes, 3 times per week) on bone mineral gain in prepubertal Asian and white boys (10.3 ± 0.6 years, 36.0 ± 9.2 kg) at 14 schools randomized to control (n = 60) and intervention (n = 61) groups. Intervention and control groups had similar mean baseline and change in height, weight, lean mass and fat mass, baseline areal bone mineral density (aBMD; g/cm2), bone mineral content (BMC; g; dual-energy X-ray absorptiometry [DXA], QDR 4500W), and similar average physical activity and calcium intakes. Over 7 months, the intervention group gained more total body (TB) BMC (1.6%, p < 0.01) and proximal femur (PF) aBMD (1%, p < 0.05) than the control group after adjusting for age, baseline weight, change in height, and loaded physical activity. We also investigated the 41 Asian and 50 white boys (10.2 ± 0.6 years and 31.9 ± 4.4 kg) who were below the 75th percentile (19.4 kg/m2) of the cohort mean for baseline body mass index (BMI). Boys in the intervention group gained significantly more TB and lumbar spine (LS) BMC, PF aBMD, and trochanteric (TR) aBMD (+ ,2%) than boys in the control group (adjusted for baseline weight, final Tanner stage, change in height, and loaded physical activity). Bone changes were similar between Asians and whites. Finally, we compared the boys in the control group (n = 16) and the boys in the intervention group (n = 14) whose baseline BMI fell in the highest quartile (10.5 ± 0.6 years and 49.1 ± 8.2 kg). Seven-month bone changes (adjusted as aforementioned) were similar in the control and intervention groups. In summary, jumping exercise augmented bone mineral accrual at several regions equally in prepubertal Asian and white boys of average or low BMI, and intervention effects on bone mineral were undetectable in high BMI prepubertal boys. [source] Structural and Expressional Variations of the Mitochondrial Genome Conferring the Wild Abortive Type of Cytoplasmic Male Sterility in RiceJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 6 2007Zhen-Lan Liu Abstract The so-called "wild abortive" (WA) type of cytoplasmic male sterility (CMS) derived from a wild rice species Oryza rufipogon has been extensively used for hybrid rice breeding. However, extensive analysis of the structure of the related mitochondrial genome has not been reported, and the CMS-associated gene(s) remain unknown. In this study, we exploited a mitochondrial genome-wide strategy to examine the structural and expressional variations in the mitochondrial genome conferring the CMS. The entire mitochondrial genomes of a CMS-WA line and two normal fertile rice lines were amplified by Long-polymerase chain reaction into tilling fragments of up to 15.2 kb. Restriction and DNA blotting analyses of these fragments revealed that structural variations occurred in several regions in the WA mitochondrial genome, as compared to those of the fertile lines. All of the amplified fragments covering the entire mitochondrial genome were used as RNA blot probes to examine the mitochondrial expression profile among the CMS-WA and fertile lines. As a result, only two mRNAs were found to be differentially expressed between the CMS-WA and the fertile lines, which were detected by a probe containing the nad5 and orf153 genes and the other having the ribosomal protein gene rpl5, respectively. These mRNAs are proposed to be the candidates for further identification and functional studies of the CMS gene. [source] Embryonic gene expression and pro-protein processing of proSAAS during rodent developmentJOURNAL OF NEUROCHEMISTRY, Issue 6 2005Daniel J. Morgan Abstract In vitro assays have demonstrated that peptides derived from the recently,identified proSAAS precursor inhibit prohormone convertase 1 (PC1) suggesting that this novel peptide may function as an endogenous inhibitor of PC1. To further understand the role of proSAAS in vivo, we have investigated the expression of proSAAS mRNA and processing of proSAAS during pre- and early postnatal rodent development. In situ hybridization showed that, by embryonic day 12.5 (e12.5) in the rat, proSAAS mRNA was present in essentially all differentiating neurons in the mantle layer of the myelencephalon, metencephalon, diencephalon, spinal cord and several sympathetic ganglia. During later stages of prenatal development, widespread proSAAS expression continues in post-mitotic neurons of both the CNS and PNS and begins in endocrine cells of the anterior and intermediate pituitary. Although proSAAS expression overlaps with PC1 in several regions, its overall expression pattern is significantly more extensive, suggesting that proSAAS may be multifunctional during development. Processed forms of proSAAS are present by at least mid-gestation with marked accumulation of two C-terminal forms, comprising the PC1 inhibitory fragment of proSAAS. [source] Neuromedin U and Neuromedin U receptor-2 expression in the mouse and rat hypothalamus: effects of nutritional statusJOURNAL OF NEUROCHEMISTRY, Issue 5 2003E. S. Graham Abstract Neuromedin U (NMU) has been associated with the regulation of food-intake and energy balance in rats. The objective of this study was to identify the sites of gene expression for NMU and the NMU receptor-2 (NMU2R) in the mouse and rat hypothalamus and ascertain the effects of nutritional status on the expression of these genes. In situ hybridization studies revealed that NMU is expressed in several regions of the mouse hypothalamus associated with the regulation of energy balance. Analysis of NMU expression in the obese ob/ob mouse revealed that NMU mRNA levels were elevated in the dorsomedial hypothalamic (DMH) nucleus of obese ob/ob mice compared to lean litter-mates. In addition, NMU mRNA levels were elevated in the DMH of mice fasted for 24 h relative to ad libitum fed controls. The pattern of expression of NMU and NMU2R were more widespread in the hypothalamus of mice than rats. These data provide the first detailed anatomical analysis of the NMU and NMU2R expression in the mouse and advance our knowledge of expression in the rat. The data from the obese rodent models supports the hypothesis that NMU is involved in the regulation of nutritional status. [source] LOWER SILURIAN "HOT SHALES" IN JORDAN: A NEW DEPOSITIONAL MODELJOURNAL OF PETROLEUM GEOLOGY, Issue 3 2009D. K. Loydell Data are presented from the Batra Formation (also known as the Mudawwara Shale Formation) of a core from well BG-14 in the Batna el Ghoul area, southern Jordan, which enable a new depositional model to be proposed for the middle Rhuddanian (lower Llandovery, Silurian) "hot shale" which may be applicable to other Arabian and North African "hot shales" of similar stratigraphical age. This "hot shale" probably results from rapid early burial of organic carbon associated with a minor regression during which anoxic bottom conditions were maintained for most, but not all, of the time. Evidence for regression comes from (1) increased sediment grain size within the "hot shale" by comparison with underlying shales; (2) palynological changes including a decrease in acritarch species diversity; an increase in the relative abundance of sphaeromorphs, veryhachiids with three processes and acritarchs with short, simple processes; and a decrease in the relative abundance of acanthomorphs; (3) a positive ,13Corg excursion (other Late Ordovician and Silurian positive ,13Corg excursions occur during regressions); and (4) very brief intervals of oxygenation (associated with sediment influx) reflected in the preservation of graptolites as three-dimensional pyrite internal moulds, rather than as flattened periderm. The minor regression reflects a eustatic sea-level fall, evidence for which has recently been presented from several regions, including Arctic Canada, Bohemia and Scotland. The BG-14 "hot shale" is shown to be thicker than estimated in previous studies. Previous TOC measurements from the upper part of the "hot shale" were affected by the weathering of overlying strata in the BG-14 core. ICP-MS measurements show that uranium content is high in these weathered levels, extending the stratigraphical extent of the "hot shale" interval into the middle Rhuddanian. Depositional models such as that presented here rely on a robust biostratigraphical framework; in the Ordovician and Silurian of Arabia and North Africa, this can be provided by graptolites and chitinozoans. [source] Identification of Susceptibility Loci for Alcohol-Related Traits in the Irish Affected Sib Pair Study of Alcohol DependenceALCOHOLISM, Issue 11 2006Po-Hsiu Kuo Background: Alcoholism is a phenotypically and probably genetically heterogeneous condition. Thus, one strategy for finding genes influencing liability to alcoholism is to study the components of alcoholism, which may be more directly related to the underlying pathophysiology than is clinical diagnosis. The goal of this study was to identify genomic regions containing susceptibility loci for alcohol-related traits. Methods: A 4-cM dense whole-genome linkage study was conducted in the Irish Affected Sib Pair Study of Alcohol Dependence. Probands, affected siblings, and parents were evaluated by structured interview. Variance component linkage analysis was applied to data from 485 families for 5 measures: initial sensitivity and tolerance (based on scales from the self-report of the effects of ethanol; maximum drinks within 24 hours, an empirically derived factor score based on withdrawal symptoms, and age at onset of alcohol dependence. Results: Evidence for linkage (p<0.005) was found on 9 chromosomes. For age at onset, 2 regions were found on chromosome 9 (highest Lod=2.3, p=0.0005). For initial level of response to alcohol, suggestive regions were on chromosomes 1 and 11 (highest Lod=2.9, p=0.0001 on chromosome 11), while those for tolerance signals were on chromosomes 1, 6, and 22. Maximum drinking was associated with regions on chromosomes 12 and 18. For withdrawal symptoms, the highest peak was on chromosome 2 (Lod=2.2, p=0.0007). Conclusions: Using quantitative measures of components of alcohol dependence, we identified several regions of the genome that may contain susceptibility loci for specific alcohol-related traits and merit additional study. [source] Clumpy shocks and the clump mass functionMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 4 2006Paul C. Clark ABSTRACT One possible mechanism for the formation of molecular clouds is large-scale colliding flows. In this paper, we examine whether clumpy, colliding, flows could be responsible for the clump mass functions that have been observed in several regions of embedded star formation, which have been shown to be described by a Salpeter-type slope. The flows presented here, which comprise a population of initially identical clumps, are modelled using smoothed particle hydrodynamics (SPH) and calculations are performed with and without the inclusion of self-gravity. When the shock region is at its densest, we find that the clump mass spectrum is always well modelled by a Salpeter-type slope. This is true regardless of whether the self-gravity is included in the simulations or not, and for our choice of filling factors for the clumpy flows (10, 20 and 40 per cent), and Mach number (5, 10 and 20). In the non-self-gravitating simulations, this slope is retained at lower Mach numbers as the simulations progress past the densest phase. In the simulations which include self-gravity, we find that low Mach number runs yield a flatter mass function after the densest phase. This is simply a result of increased coagulation due to gravitational collapse of the flows. In the high Mach number runs the Salpeter slope is always lost. The self-gravitating calculations also show that the subgroup of gravitationally bound clumps in which star formation occurs, always contain the most massive clumps in the population. Typically these clumps have a mass of order of the Jeans mass of the initial clumps. The mass function of these bound star-forming clumps is not at all similar to the Salpeter-type mass function observed for stars in the field. We conclude that the clump mass function may not only have nothing to do with gravity, but also nothing to do with the star formation process and the resulting mass distribution of stars. This raises doubt over the claims that the clump mass function is the origin of the stellar initial mass function (IMF), for regions such as , Oph, Serpens and the Orion B cloud. [source] Contexts of Monumentalism: regional diversity at the Neolithic transition in north-west FranceOXFORD JOURNAL OF ARCHAEOLOGY, Issue 1 2002Chris Scarre The origins of funerary monumentalism in north-west France remain inextricably linked to questions surrounding the Neolithic transition in that region. Debate continues over the relative importance of influences from earlier Neolithic communities in north-east or southern France on the Mesolithic communities of western France. An alternative interpretation places these influences within the context of broad processes of change affecting indigenous communities throughout northern and western France during the fifth millennium BC. The evidence from several regions of northern and western France is reviewed in this perspective, with emphasis on the regional character of monument traditions. Though at one level these regional narratives must have been interrelated, the regional diversity of the process must also be underlined. The argument moves us away from simplistic notions of extraneous influences to a more nuanced understanding of change within the context of individual communities at the Mesolithic/Neolithic transition. [source] A one-sided MEWMA chart for health surveillanceQUALITY AND RELIABILITY ENGINEERING INTERNATIONAL, Issue 5 2008Michael D. Joner Jr Abstract It is often important to rapidly detect an increase in the incidence rate of a given disease or other medical condition. It has been shown that when disease counts are sequentially available from a single region, a univariate control chart designed to detect rate increases, such as a one-sided cumulative sum chart, is very effective. When disease counts are available from several regions at corresponding times, the most efficient monitoring method is not readily apparent. Multivariate monitoring methods have been suggested for dealing with this detection problem. Some of these approaches have shortcomings that have been recently demonstrated in the quality control literature. We discuss these limitations and suggest an alternative multivariate exponentially weighted moving average chart. We compare the average run-length performance of this chart with that of competing methods. We also evaluate the statistical performance of these charts when the actual increase in the disease count rate is different from the one that the chart was optimized to detect quickly. Copyright © 2008 John Wiley & Sons, Ltd. [source] Generation of a flanking sequence-tag database for activation-tagging lines in japonica riceTHE PLANT JOURNAL, Issue 1 2006Dong-Hoon Jeong Summary We have generated 47 932 T-DNA tag lines in japonica rice using activation-tagging vectors that contain tetramerized 35S enhancer sequences. To facilitate use of those lines, we isolated the genomic sequences flanking the inserted T-DNA via inverse polymerase chain reaction. For most of the lines, we performed four sets of amplifications using two different restriction enzymes toward both directions. In analyzing 41 234 lines, we obtained 27 621 flanking sequence tags (FSTs), among which 12 505 were integrated into genic regions and 15 116 into intergenic regions. Mapping of the FSTs on chromosomes revealed that T-DNA integration frequency was generally proportional to chromosome size. However, T-DNA insertions were non-uniformly distributed on each chromosome: higher at the distal ends and lower in regions close to the centromeres. In addition, several regions showed extreme peaks and valleys of insertion frequency, suggesting hot and cold spots for T-DNA integration. The density of insertion events was somewhat correlated with expressed, rather than predicted, gene density along each chromosome. Analyses of expression patterns near the inserted enhancer showed that at least half the test lines displayed greater expression of the tagged genes. Whereas in most of the increased lines expression patterns after activation were similar to those in the wild type, thereby maintaining the endogenous patterns, the remaining lines showed changes in expression in the activation tagged lines. In this case, ectopic expression was most frequently observed in mature leaves. Currently, the database can be searched with the gene locus number or location on the chromosome at http://www.postech.ac.kr/life/pfg/risd. On request, seeds of the T1 or T2 plants will be provided to the scientific community. [source] | |||||||||||||||||||||||||||||||||||||