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Selected AbstractsSpatial distribution and environmental correlates of Australian snubfin and Indo-Pacific humpback dolphinsECOGRAPHY, Issue 3 2006Guido J. Parra We present data on the spatial distribution of Australian snubfin and humpback dolphins using boat-based line transect surveys in three adjacent bays located in the Far Northern Section of the Great Barrier Reef Marine Park, northeast Queensland. We used Geographic Information Systems (GIS), and both randomization and Mantel tests to examine the relationship between the spatial distribution of the dolphins and three simple, readily quantified, environmental variables: distance to land, distance to river mouth, and water depth. Mantel tests allowed us to make clear inferences about the correlation of the species' distributions with environmental variables, while taking into account spatial autocorrelation and intercorrelation among variables. Randomization tests indicated snubfin and humpback dolphins occur closer to land than would be expected at random. Two-sample randomization tests indicated snubfin dolphins were found closer to river mouths than were humpback dolphins. Taking spatial autocorrelation into account, Mantel tests indicated all environmental variables were correlated with the spatial distribution of snubfin and humpback dolphins. Interspecific differences in spatial distribution appeared to be related to proximity to river mouths. Preference by snubfin and humpback dolphins for nearshore, estuarine waters is likely related to the productivity of these tropical coastal areas. This spatial analysis suggests that existing protected areas in this region may not include the most critical habitats for snubfin and humpback dolphins. The techniques used here shown relationships between the spatial distribution of the dolphins and environmental features that should facilitate their management and conservation. [source] The wealth of species: ecological communities, complex systems and the legacy of Frank PrestonECOLOGY LETTERS, Issue 3 2007Jeffrey C. Nekola Abstract General statistical patterns in community ecology have attracted considerable recent debate. Difficulties in discriminating among mathematical models and the ecological mechanisms underlying them are likely related to a phenomenon first described by Frank Preston. He noted that the frequency distribution of abundances among species was uncannily similar to the Boltzmann distribution of kinetic energies among gas molecules and the Pareto distribution of incomes among wage earners. We provide additional examples to show that four different ,distributions of wealth' (species abundance distributions, species,area and species,time relations, and distance decay of compositional similarity) are not unique to ecology, but have analogues in other physical, geological, economic and cultural systems. Because these appear to be general statistical patterns characteristic of many complex dynamical systems they are likely not generated by uniquely ecological mechanistic processes. [source] Anatomy of employment growthECONOMIC POLICY, Issue 34 2002Pietro Garibaldi Summary This paper studies net employment growth across 21 OECD economies since 1980, focusing on the wide range of experiences within the European Union. The initial composition of employment across sectors is relevant in a few countries, but can only partially account for cross-country differences in net employment growth. Institutions play a more important role. A policy package including low dismissal costs and low taxation is significantly associated with high net employment growth and can account for a substantial share of cross-country differences. While the Netherlands' employment miracle is largely accounted for by an increase in part-time jobs for women aged 25,49 in the services sector, we find that in the whole sample part-time jobs largely replace full-time jobs, and temporary jobs replace permanent jobs, with small net effects on hours worked. Continental Europe did not increase employment as much as other OECD countries until the mid-1990s, but later appears to be staging a resurgence of employment growth. We argue that this resurgence is not merely cyclical, is likely related to reforms, and may well be there to stay. [source] Inorganic arsenic induces necrosis of human CD34-positive haematopoietic stem cellsENVIRONMENTAL TOXICOLOGY, Issue 2 2008Laurent Vernhet Abstract Inorganic arsenic is a major environmental contaminant known to exert immunosuppressive effects. In this study, we report toxicity of As2O3, a trivalent inorganic form, toward isolated human hematopoietic CD34+ progenitor cells. Our results demonstrate that low concentrations of As2O3 (0.1,5 ,M) inhibit in vitro proliferation of CD34+ cells and their differentiation into various hematological cell lineages. These effects were associated with the induction of a necrotic process independent of caspases and likely related to mitochondrial damage. We conclude that As2O3 can impair in vitro human hematopoiesis by decreasing survival of CD34+ progenitor cells. © 2008 Wiley Periodicals, Inc. Environ Toxicol, 2008. [source] Study of cord blood natural killer cell suppressor activityEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 4 2001S. El Marsafy Abstract: We tested the immunosuppressive effect of cord blood (CB) natural killer (NK) cells using highly purified CB NK cells in mixed lymphocyte cultures (MLC) containing autologous CB T cells as responders. Control cultures were done without NK cells. Our findings revealed that CB NK cells induced a dose-dependent inhibition of T lymphocyte proliferation as evidenced by decreased 3H-thymidine incorporation in MLC. The T cell alloproliferation was significantly decreased in the presence of an NK cell to responder cell ratio of 0.1, 0.2 or 0.4 compared with control cultures done without NK cells (p=0.02, 0.003 and 0.0002, respectively). T lymphocyte inhibition was also achieved using irradiated CB NK cells and still demonstrable on addition of disparate CB NK and T cells to the MLC. In agreement with previous reports, adult blood NK cells inhibited the alloreactive T cells in the MLC using adult T lymphocytes as responders. Compared to control cultures done without NK cells, statistically significant inhibition of 3H-thymidine incorporation in MLC was observed at a ratio of NK cells to responder cells ratio of 0.2 or 0.4 (p=0.02). To investigate the mechanism whereby CB NK cells can interfere with the development of alloreactive T cells in MLC, we measured the tumour necrosis factor-, (TNF-,) concentrations in MLC supernatants using NK cell-depleted or unseparated CB mononuclear cells (MNC) as responders. The results revealed significantly high levels of TNF-, in the absence of NK cells (p=0.007). We conclude that CB NK cells suppress alloreactive T lymphocytes as do their counterparts in adult blood. However, the high NK to T cell ratio in CB could contribute to a more marked suppressive potential compared to that in adult blood. The mechanism of NK-mediated inhibition is likely related to disruption of the TNF-, pathway of T-lymphocyte activation. [source] Differences in endozoochorous dispersal between aquatic plant species, with reference to plant population persistence in riversFRESHWATER BIOLOGY, Issue 2 2005B. J. A. POLLUX Summary 1. In river ecosystems, populations are continuously subjected to unidirectional downstream currents resulting in a downstream movement of populations. To ensure long-term population persistence in rivers, organisms must have a mechanism for upstream dispersal, which allows them to re-colonise upstream areas. 2. In this study we assessed differences in the potential for endozoochorous seed dispersal of Sparganium emersum and Sagittaria sagittifolia, two aquatic plant species with different seed morphologies, by mallard (Anas platyrhynchos) and teal (Anas crecca), two duck species with different body weights. 3. We found no significant differences in seed retrieval (the proportion of ingested seeds retrieved after gut passage) and seed retention time (time between seed ingestion and retrieval), between mallard and teal, despite the difference in body weights. We did find a significantly higher germination (%) over retention time of S. emersum seeds retrieved from teal compared with mallard, most likely related to a more efficient removal of the seed coat during passage through the gut of teal. 4. There were large differences between S. emersum versus S. sagittifolia in: (i) seed retrieval (22.65 ± 20.8% versus 1.60 ± 2.4%, respectively); (ii) seed retention time in duck gut, with a maximum of 60 h versus 12 h; (iii) the effect of gut passage on seed germination, with an increase of approximately 35% versus a decrease of 25%; and (iv) the effect of gut passage on seed germination rate, with an acceleration of 10 days versus a delay of 3 days on average. The results show that S. emersum has a higher potential for endozoochorous dispersal by ducks and postdispersal establishment than S. sagittifolia. 5. We propose that, in rivers, bird-mediated seed dispersal may promote re-colonisation of upstream areas, enabling long-term plant population persistence. [source] Paleoindian environmental change and landscape response in Barger Gulch, Middle Park, ColoradoGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 6 2005James H. Mayer Middle Park, a high-altitude basin in the Southern Rocky Mountains of north-central Colorado, contains at least 59 known Paleoindian localities. At Barger Gulch Locality B, an extensive Folsom assemblage (,10,500 14C yr B.P.) occurs within a buried soil. Radiocarbon ages of charcoal and soil organic matter, as well as stratigraphic positions of artifacts, indicate the soil is a composite of a truncated, latest-Pleistocene soil and a younger mollic epipedon formed between ,6000 and 5200 14C yr B.P. and partially welded onto the older soil following erosion and truncation. Radiocarbon ages from an alluvial terrace adjacent to the excavation area indicate that erosion followed by aggradation occurred between ,10,200 and 9700 14C yr B.P., and that the erosion is likely related to truncation of the latest-Pleistocene soil. Erosion along the main axis of Barger Gulch occurring between ,10,000 and 9700 14C yr B.P. was followed by rapid aggradation between ,9700 and 9550 14C yr B.P., which, along with the erosion at Locality B, coincides with the abrupt onset of monsoonal precipitation following cooling in the region ,11,000,10,000 14C yr B.P. during the Younger Dryas oscillation. Buried soils dated between ,9500 and 8000 14C yr B.P. indicate relative landscape stability and soil formation throughout Middle Park. Morphological characteristics displayed by early Holocene soils suggest pedogenesis under parkland vegetation in areas currently characterized by sagebrush steppe. The expansion of forest cover into lower elevations during the early Holocene may have resulted in lower productivity in regards to mammalian fauna, and may partly explain the abundance of early Paleoindian sites (,11,000,10,000 14C yr B.P., 76%) relative to late Paleoindian sites (,10,000,8000 14C yr B.P., 24%) documented in Middle Park. © 2005 Wiley Periodicals, Inc. [source] Diagenesis of the Amposta offshore oil reservoir (Amposta Marino C2 well, Lower Cretaceous, Valencia Trough, Spain)GEOFLUIDS (ELECTRONIC), Issue 3 2010E. PLAYÀ Abstract Samples from the Amposta Marino C2 well (Amposta oil field) have been investigated in order to understand the origin of fractures and porosity and to reconstruct the fluid flow history of the basin prior, during and after oil migration. Three main types of fracture systems and four types of calcite cements have been identified. Fracture types A and B are totally filled by calcite cement 1 (CC1) and 2 (CC2), respectively; fracture type A corresponds to pre-Alpine structures, while type B is attributed to fractures developed during the Alpine compression (late Eocene-early Oligocene). The oxygen, carbon and strontium isotope compositions of CC2 are close to those of the host-rock, suggesting a high degree of fluid-rock interaction, and therefore a relatively closed palaeohydrogeological system. Fracture type C, developed during the Neogene extension and enlarged by subaerial exposure, tend to be filled with reddish (CS3r) and greenish (CS3g) microspar calcite sediment and blocky calcite cement type 4 (CC4), and postdated by kaolinite, pyrite, barite and oil. The CS3 generation records lower oxygen and carbon isotopic compositions and higher 87Sr/86Sr ratios than the host-limestones. These CS3 karstic infillings recrystallized early within evolved-meteoric waters having very little interaction with the host-rock. Blocky calcite cement type 4 (CC4 generation) has the lowest oxygen isotope ratio and the most radiogenic 87Sr/86Sr values, indicating low fluid-rock interaction. The increasingly open palaeohydrogeological system was dominated by migration of hot brines with elevated oxygen isotope ratios into the buried karstic system. The main oil emplacement in the Amposta reservoir occurred after the CC4 event, closely related to the Neogene extensional fractures. Corrosion of CC4 (blocky calcite cement type 4) occurred prior to (or during) petroleum charge, possibly related to kaolinite precipitation from relatively acidic fluids. Barite and pyrite precipitation occurred after this corrosion. The sulphur source associated with the late precipitation of pyrite was likely related to isotopically light sulphur expelled, e.g. as sulphide, from the petroleum source rock (Ascla Fm). Geofluids (2010) 10, 314,333 [source] Contrasting responses of migration strategies in two European thrushes to climate changeGLOBAL CHANGE BIOLOGY, Issue 1 2007PHILIPPE RIVALAN Abstract Migration is a widespread strategy that enables animals to escape harsh winter conditions. It has been well documented that migration phenology in birds is changing in response to recent climate warming in the northern hemisphere. Despite the existence of large temporal and geographical scale ringing data on birds in Europe, changes in migration strategies in relation to climate warming have not been well studied, mainly because of a lack of appropriate statistical methods. In this paper, we develop a method that enables us to investigate temporal changes in migration strategies from recoveries of dead ringed birds. We estimated migration probability as the ratio between recovery probabilities of conspecific birds originating from different countries but potentially wintering in the same country. We applied this method to two European thrushes: the entirely migrant redwing Turdus iliacus, and the partially migrant blackbird T. merula. We tested for an immediate and a 1-year lagged relationship between our migration probability and climatic covariates (i.e. mean winter temperature in France and the North Atlantic Oscillation). Using ringing-recovery data collected in Finland, Germany, Switzerland and France from 1970 to 1999, we detected contrasting responses in these two species, likely related to their different migratory behaviours. Both species showed a decline in the probability for northern and eastern birds to winter in France. The entirely migratory redwing exhibited a year-to-year plastic response to climate, whereas the decline in the partially migrant blackbird was smooth, suggesting underlying genetic processes. The proposed method, thus, allows us to identify useful indicators of climatic impacts on migration strategies, as well as highlighting differences between closely related species. [source] North American Brant: effects of changes in habitat and climate on population dynamicsGLOBAL CHANGE BIOLOGY, Issue 6 2005David H. Ward Abstract We describe the importance of key habitats used by four nesting populations of nearctic brant (Branta bernicla) and discuss the potential relationship between changes in these habitats and population dynamics of brant. Nearctic brant, in contrast to most geese, rely on marine habitats and native intertidal plants during the non-breeding season, particularly the seagrass, Zostera, and the macroalgae, Ulva. Atlantic and Eastern High Arctic brant have experienced the greatest degradation of their winter habitats (northeastern United States and Ireland, respectively) and have also shown the most plasticity in feeding behavior. Black and Western High Arctic brant of the Pacific Flyway are the most dependent on Zostera, and are undergoing a shift in winter distribution that is likely related to climate change and its associated effects on Zostera dynamics. Variation in breeding propensity of Black Brant associated with winter location and climate strongly suggests that food abundance on the wintering grounds directly affects reproductive performance in these geese. In summer, salt marshes, especially those containing Carex and Puccinellia, are key habitats for raising young, while lake shorelines with fine freshwater grasses and sedges are important for molting birds. Availability and abundance of salt marshes has a direct effect on growth and recruitment of goslings and ultimately, plays an important role in regulating size of local brant populations. [source] Regional-scale measurements of CH4 exchange from a tall tower over a mixed temperate/boreal lowland and wetland forestGLOBAL CHANGE BIOLOGY, Issue 9 2003Cindy Werner The biosphere,atmosphere exchange of methane (CH4) was estimated for a temperate/boreal lowland and wetland forest ecosystem in northern Wisconsin for 1997,1999 using the modified Bowen ratio (MBR) method. Gradients of CH4 and CO2 and CO2 flux were measured on the 447-m WLEF-TV tower as part of the Chequamegon Ecosystem,Atmosphere Study (ChEAS). No systematic diurnal variability was observed in regional CH4 fluxes measured using the MBR method. In all 3 years, regional CH4 emissions reached maximum values during June,August (24±14.4 mg m,2 day,1), coinciding with periods of maximum soil temperatures. In 1997 and 1998, the onset in CH4 emission was coincident with increases in ground temperatures following the melting of the snow cover. The onset of emission in 1999 lagged 100 days behind the 1997 and 1998 onsets, and was likely related to postdrought recovery of the regional water table to typical levels. The net regional emissions were 3.0, 3.1, and 2.1 g CH4 m,2 for 1997, 1998, and 1999, respectively. Annual emissions for wetland regions within the source area (28% of the land area) were 13.2, 13.8, and 10.3 g CH4 m,2 assuming moderate rates of oxidation of CH4 in upland regions in 1997, 1998, and 1999, respectively. Scaling these measurements to the Chequamegon Ecosystem (CNNF) and comparing with average wetland emissions between 40°N and 50°N suggests that wetlands in the CNNF emit approximately 40% less than average wetlands at this latitude. Differences in mean monthly air temperatures did not affect the magnitude of CH4 emissions; however, reduced precipitation and water table levels suppressed CH4 emission during 1999, suggesting that long-term climatic changes that reduce the water table will likely transform this landscape to a reduced source or possibly a sink for atmospheric CH4. [source] Fatal central venous catheter-related infection in haemophiliaHAEMOPHILIA, Issue 2 2006S. E. CRARY Summary., Central venous catheters (CVC) are frequently used in children with haemophilia to deliver factor infusions for the treatment or prophylaxis of bleeding. Complications of CVCs in patients with haemophilia include thrombosis and infection. We report a young boy with severe haemophilia A and an inhibitor who developed disseminated Staphylococcus aureus infection most likely related to a CVC. To our knowledge, this is the first reported case of fatal sepsis secondary to a CVC in a patient with haemophilia. [source] Factors affecting outcome in liver resectionHPB, Issue 3 2005CEDRIC S. F. LORENZO Abstract Background. Studies demonstrate an inverse relationship between institution/surgeon procedural volumes and patient outcomes. Similar studies exist for liver resections, which recommend referral of patients for liver resections to ,high-volume' centers. These studies did not elucidate the factors that underlie such outcomes. We believe there exists a complex interaction of patient-related and perioperative factors that determine patient outcomes after liver resection. We sought to delineate these factors. Methods. Retrospective review of 114 liver resections by a single surgeon from 1993,2003: Records were reviewed for demographics; diagnosis; type/year of surgery; American Society of Anesthesiologists (ASA) score; preoperative albumin, creatinine, and bilirubin; operative time; intraoperative blood transfusions; epidural use; and intraoperative hypotension. Main outcome measurements were postoperative morbidities, mortalities and length of stay (LOS). Data were analyzed using a multivariate linear regression model (SPSS v10.1 statistical analysis program). Results. Primary indications for resections were hepatocellular carcinoma (HCC) (N=57), metastatic colorectal cancer (N=25), and benign disease (N=18). There were no intraoperative mortalities and 4 perioperative (30-day) mortalities (3.5%). Mortality occurred in patients with malignancies who were older than 50 years. Morbidity was higher in malignant (15.6%) versus benign (5.5%) disease. Complications included bile leak/stricture (N=6), liver insufficiency (N=3), postoperative bleeding (N=2), myocardial infarction (N=2), aspiration pneumonia (N=1), renal insufficiency (N=1), and cancer implantation into the wound (N=1). Average LOS for all resections was 8.6 days. Longer operative time (p=0.04), lower albumin (p<0.001), higher ASA score (p<0.001), no epidural use (p=0.04), and higher creatinine (p<0.001) all correlated positively with longer LOS. ASA score and creatinine were the strongest predictors of LOS. LOS was not affected by patient age, sex, diagnosis, presence of malignancy, intraoperative transfusion requirements, intraoperative hypotension, preoperative bilirubin, case volume per year or year of surgery. Conclusions. Liver resections can be performed with low mortality/morbidity and with acceptable LOS by an experienced liver surgeon. Outcome as measured by LOS is most influenced by patient comorbidities entering into surgery. Annual case volume did not influence LOS and had no impact on patient safety. Length of stay may not reflect surgeon/institution performance, as LOS is multifactorial and likely related to patient population, patient selection and increased high-risk cases with a surgeon's experience. [source] Changes in hydrology and erosion over a transition from grassland to shrublandHYDROLOGICAL PROCESSES, Issue 4 2010Laura Turnbull Abstract The degradation of grasslands is a common problem across semi-arid areas worldwide. Over the last 150 years, much of the south-western United States has experienced significant land degradation, with desert grasslands becoming dominated by shrubs and concurrent changes in runoff and erosion which are thought to propagate further the process of degradation. Plot-based experiments to determine how spatio-temporal characteristics of soil moisture, runoff and erosion change over a transition from grassland to shrubland were carried out at four sites over a transition from black grama (Bouteloua eriopoda) grassland to creosotebush (Larrea tridentata) shrubland at the Sevilleta NWR LTER site in New Mexico. Each site consisted of a 10 × 30 m bounded runoff plot and adjacent characterization plots with nested sampling points where soil moisture content was measured. Results show distinct spatio-temporal variations in soil moisture content, which are due to the net effect of processes operating at multiple spatial and temporal scales, such as plant uptake of water at local scales versus the redistribution of water during runoff events at the hillslope scale. There is an overall increase in runoff and erosion over the transition from grassland to shrubland, which is likely to be associated with an increase in connectivity of bare, runoff-generating areas, although these increases do not appear to follow a linear trajectory. Erosion rates increased over the transition from grassland to shrubland, likely related in part to changes in runoff characteristics and the increased capacity of the runoff to detach, entrain and transport sediment. Over all plots, fine material was preferentially eroded which has potential implications for nutrient cycling since nutrients tend to be associated with fine sediment. Copyright © 2009 John Wiley & Sons, Ltd. [source] Simultaneous analyses and applications of multiple fluorobenzoate and halide tracers in hydrologic studiesHYDROLOGICAL PROCESSES, Issue 14 2005Qinhong Hu Abstract An analytical method that employs ion chromatography has been developed to exploit the use of fluorobenzoic acids (FBAs) and halides more fully as hydrologic tracers. In a single run, this reliable, sensitive, and robust method can simultaneously separate and quantify halides (fluoride, chloride, bromide, and iodide) and up to seven FBAs from other common groundwater constituents (e.g. nitrate and sulphate). The usefulness of this analytical method is demonstrated in both field and laboratory tracer experiments. The field study examines the hydrologic response of fractures and the matrix to different flow rates and the contribution of matrix diffusion in chemical transport. Laboratory tracer experiments with eight geologic media from across the USA,mostly from Department of Energy facilities where groundwater contamination is prevalent and where subsurface characterization employing tracers has been ongoing or is in need,reveal several insights about tracer transport behaviour: (1) bromide and FBAs are not always transported conservatively; (2) the delayed transport of these anionic tracers is likely related to geologic media characteristics, such as organic matter, pH, iron oxide content, and clay mineralogy; (3) use of iodine as a hydrologic tracer should take into account the different sorption behaviours of iodide and iodate and the possible conversion of iodine's initial chemical form; (4) the transport behaviour of potential FBA and halide tracers under relevant geochemical conditions should be evaluated before beginning ambitious, large-scale field tracer experiments. Copyright © 2005 John Wiley & Sons, Ltd. [source] Sarcoidosis presenting with granulomatous uveitis induced by pegylated interferon and ribavirin therapy for hepatitis CINTERNAL MEDICINE JOURNAL, Issue 3 2008K. K. L. Yan Abstract Sarcoidosis is a systemic granulomatous disease that is triggered by an autoimmune process, and is now a well recognized but uncommon complication of antiviral therapy for Hepatitis C virus (HCV) infection, likely related to its immunomodulatory effects. The clinical presentation of HCV related sarcoidosis is as varied as systemic sarcoidosis, but ocular presentation alone has not been reported previously. We present a 23 year-old female who developed visual disturbances due to ocular sarcoidosis during the course of antiviral therapy for chronic HCV infection. Our case presentation is then followed by a review of the literature on the topic. We aim to stress the importance of screening for eye problems in following HCV patients undergoing antiviral therapy, and raise clinicians' awareness of sarcoidosis as a possible cause for eye problems even in the absence of respiratory complaints. [source] Global atmospheric energetics from NCEP,Reanalysis 2 and ECMWF,ERA40 ReanalysisINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 2 2009Carlos A. F. Marques Abstract The global atmospheric energy cycle is estimated on an annual basis using Reanalysis 2 data from the National Centers for Environmental Prediction and National Center for Atmospheric Research (NCEP/NCAR), and ERA 40 Reanalyses from the European Centre for Medium-Range Weather Forecasts (ECMWF) for the period 1979,2001. A formalism to avoid belowground data on pressure levels intercepted by topography is adopted. No appreciable differences were found between the two datasets from the energetics point of view. The so-called ,, and v·grad z formulations were both used for the conversions from zonal available potential energy into zonal kinetic energy (CZ) and from eddy available potential energy into eddy kinetic energy (CE). Results with both formulations are comparable only when using the formalism preventing belowground data to enter into the computations. Atmospheric energetics are also computed using ECMWF Reanalyses for the period 1958,1978. A significant increase was found in the eddy kinetic and eddy available potential energies from the early period to the later period, likely related to the assimilation in the reanalyses of satellite data after 1979. The conversion rate, CZ, was found to change its sign throughout the years. The atmospheric energy cycle using the ECMWF Reanalyses data is compared with five previous estimates. Differences in the direction of the conversion rate, CZ, between the various estimates may be explained by the different time periods chosen for averaging. Owing to the omission of belowground data, the conversion from zonal available potential energy into eddy available potential energy (CA) was somewhat smaller in ECMWF Reanalyses than in the previous estimates. Despite those differences, an overall agreement may be found between the various estimates for the atmospheric energy cycle. Copyright © 2008 Royal Meteorological Society [source] Evaluating cognition in an elderly cohort via telephone assessmentINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 5 2010Effie M. Mitsis Abstract Objective Longitudinal neuropsychological assessment provides the opportunity to observe the earliest transition to cognitive impairment in healthy, elderly individuals. We examined the feasibility, and its comparability to in-person assessment, of a telephone administered battery of established neuropsychological measures of cognitive functioning in healthy, elderly women. Methods Fifty-four women (age,=,79,±,7.7; education,=,15.4,±,3.3) who were in self-reported good health were recruited from senior centers and other community sources. A two-way cross-over design was used in which participants were randomly assigned to receive either (1) in-person neuropsychological assessment followed by telephone assessment and (2) telephone assessment followed by in-person assessment, separated by approximately 4 weeks. Linear regression models were used to determine whether there were performance differences by method (in-person vs. telephone), and equivalence testing assessed comparability of the two methods. Results There were no statistically significant differences in performance between in-person and telephone assessments on most neuropsychological tests, with the exception of digit span backward, Oral Trail Making Test Part A, and delayed recall on the SRT, the latter likely related to non-comparable exposure (6-trials in-person vs. 3-trials telephone). Equivalence testing differences fell in the pre-specified clinical equivalence zones, providing evidence of comparability of the two methods. Conclusions These pilot data support telephone administration of a neuropsychological battery that yields comparable performance to in-person assessment with respect to most instruments. Significant differences in scores on some measures suggest care should be taken in selecting specific measures used in a neuropsychological battery administered by telephone. Copyright © 2009 John Wiley & Sons, Ltd. [source] Zircon U,Pb ages and tectonic implications of ,Early Paleozoic' granitoids at Yanbian, Jilin Province, northeast ChinaISLAND ARC, Issue 4 2004Yanbin Zhang Abstract The Yanbian area is located in the eastern part of the Central Asian Orogenic Belt (CAOB) of China and is characterized by widespread Phanerozoic granitic intrusions. It was previously thought that the Yanbian granitoids were mainly emplaced in the Early Paleozoic (so-called ,Caledonian' granitoids), extending east,west along the northern margin of the North China craton. However, few of them have been precisely dated; therefore, five typical ,Caledonian' granitic intrusions (the Huangniling, Dakai, Mengshan, Gaoling and Bailiping batholiths) were selected for U,Pb zircon isotopic study. New-age data show that emplacement of these granitoids extended from the Late Paleozoic to Late Mesozoic (285,116 Ma). This indicates that no ,Caledonian' granitic belt exists along the northern margin of the North China craton. The granitoids can be subdivided into four episodes based on our new data: Early Permian (285 ± 9 Ma), Early Triassic (249,245 Ma), Jurassic (192,168 Ma) and Cretaceous (119,116 Ma). The 285 ± 9 Ma tonalite was most likely related to subduction of the Paleo-Asian Oceanic Plate beneath the North China craton, followed by Triassic (249,245 Ma) syn-collisional monzogranites, representing the collision of the CAOB orogenic collage with the North China craton and final closure of the Paleo-Asian Ocean. The Jurassic granitoids resulted from subduction of the Paleo-Pacific plate and subsequent collision of the Jiamusi,Khanka Massif with the existing continent, assembled in the Triassic. The Early Cretaceous granitoids formed in an extensional setting along the eastern Asian continental margin. [source] Patterns of mortality for each life-history stage in a population of the endangered New Zealand stitchbirdJOURNAL OF ANIMAL ECOLOGY, Issue 4 2009Matthew Low Summary 1Using data from 396 breeding attempts over an 8-year period, we investigated age- and stage-specific survival rates and their modifying factors in a closed island population of the New Zealand stitchbird (or hihi, Notiomystis cincta Du Bus). 2Survival probability generally increased over time; however, at each life-history transition, survival in the new stage started lower than at the end of the previous stage, creating a ,saw-tooth' function of age-related survival. 3The probability of an egg hatching was low (0·73 ± 0·01): most likely a consequence of genetic bottlenecks previously endured by this population. There was strong support for a positive relationship between hatching rate and the subsequent survival of the female parent, and hatching success declining for females > 4 years old. 4Nestling survival probability increased as a function of brood size and days since hatching, and decreased relative to daily maximum ambient temperature and hatching date. Support for models including ambient temperature was greater than for other covariates, with the majority of this temperature-mediated survival effect being restricted to the early nestling stage. 5Fledglings had low survival rates in the first two weeks after leaving the nest, with post-fledging survival related to the fledgling's mass. Two months after fledging, juvenile survival probability plateaued and remained relatively constant for the following autumn, winter and spring/summer breeding season. There was no effect of sex or season on adult survival probability. However, there was strong support for age-specific variation in adult survival, with survival likelihood increasing during the first four years before showing evidence of a senescence decline. 6Within-stage survival increases were likely related to stage-specific selection pressures initially weeding out individuals of poorer phenotypes for the environment specific to each life-history stage. Such a mechanism explains the initial high mortality at life-history transitions; a well-adapted phenotype for one stage may not necessarily be so well adapted for subsequent stages. These patterns are not only valuable for examining life-history theory, but also for understanding the regulation of vital rates in an endangered species and providing a basis from which better population management models and harvesting regimes can be derived. [source] An Evaluation of Determination of Handedness Using Standard Osteological Measurements,JOURNAL OF FORENSIC SCIENCES, Issue 4 2008Marie Elaine Danforth Ph.D. Abstract:, Numerous studies have assessed side dominance assuming arm bones on the side of handedness will be larger, but concerns over sample size or replicability of measurements usually emerged. Attempting to improve upon these limitations, this investigation analyzes patterns of side difference for standard length and transverse dimensions of the scapula, clavicle, humerus, ulna, and radius for 137 individuals of known handedness. The results showed that with few exceptions, the right side of the skeleton was consistently larger in most individuals regardless of side dominance. Combinations of other measurements previously suggested to be indicative of handedness as well as the use of discriminant analysis also failed to provide reliable estimators. These findings are likely related to the fact that activities of modern individuals are generally not sufficiently unilateral in their stresses to cause asymmetrical development in the arm bones. Therefore, it is recommended that other means be developed to assess side dominance. [source] Relics of the Mozambique Ocean in the central East African Orogen: evidence from the Vohibory Block of southern MadagascarJOURNAL OF METAMORPHIC GEOLOGY, Issue 1 2008N. JÖNS Abstract The Vohibory Block of south-western Madagascar is part of the East African Orogen, the formation of which is related to the assembly of the Gondwana supercontinent. It is dominated by metabasic rocks, which have chemical compositions similar to those of recent basalts from a mid-ocean ridge, back-arc setting and island-arc setting. The age of formation of protolith basalts has been dated at 850,700 Ma by U,Pb SHRIMP analysis of magmatic cores in zircon, pointing to an origin related to the Neoproterozoic Mozambique Ocean. The metabasic rocks are interpreted as representing components of an island arc with an associated back-arc basin. In the early stage of the Pan-African orogeny, these rocks experienced high-pressure amphibolite to granulite facies metamorphism (9,12 kbar, 750,880 °C), dated at 612 ± 5 Ma from metamorphic rims in zircon. The metamorphism was most likely related to accretion of the arc terrane to the margin of the Azania microcontinent (Proto-Madagascar) and closure of the back-arc basin. The main metamorphism is significantly older than high-temperature metamorphism in other tectonic units of southern Madagascar, indicating a distinct tectono-metamorphic history. [source] A counter-clockwise P,T path for the Voltri Massif eclogites (Ligurian Alps, Italy)JOURNAL OF METAMORPHIC GEOLOGY, Issue 7 2005G. VIGNAROLI Abstract Integrated petrological and structural investigations of eclogites from the eclogite zone of the Voltri Massif (Ligurian Alps) have been used to reconstruct a complete Alpine P,T deformation path from burial by subduction to subsequent exhumation. The early metamorphic evolution of the eclogites has been unravelled by correlating garnet zonation trends with the chemical variations in inclusions found in the different garnet domains. Garnet in massive eclogites displays typical growth zoning, whereas garnet in foliated eclogites shows rim-ward resorption, likely related to re-equilibration during retrogressive evolution. Garnet inclusions are distinctly different from core to rim, consisting primarily of Ca-, Na/Ca-amphibole, epidote, paragonite and talc in garnet cores and of clinopyroxene ± talc in the outer garnet domains. Quantitative thermobarometry on the inclusion assemblages in the garnet cores defines an initial greenschist-to-amphibolite facies metamorphic stage (M1 stage) at c. 450,500 °C and 5,8 kbar. Coexistence of omphacite + talc + katophorite inclusion assemblage in the outer garnet domains indicate c. 550 °C and 20 kbar, conditions which were considered as minimum P,T estimates for the M2 eclogitic stage. The early phase of retrograde reactions is polyphase and equilibrated under epidote,blueschist facies (M3 stage), characterized by the development of composite reaction textures (garnet necklaces and fluid-assisted Na-amphibole-bearing symplectites) produced at the expense of the primary M2 garnet-clinopyroxene assemblage. The blueschist retrogression is contemporaneous with the development of a penetrative deformation (D3) that resulted in a non-coaxial fabric, with dominant top-to-the-N sense of shear during rock exhumation. All of that is overprinted by a texturally late amphibolite/greenschist facies assemblages (M4 & M5 stages), which are not associated with a penetrative structural fabric. The combined P,T deformation data are consistent with an overall counter-clockwise path, from the greenschist/amphibolite, through the eclogite, the blueschist to the greenschist facies. These new results provide insights into the dynamic evolution of the Tertiary oceanic subduction processes leading to the building up of the Alpine orogen and the mechanisms involved in the exhumation of its high-pressure roots. [source] ,-cyclodextrin reduces bioavailability of orally administered [3H]benzo[a]pyrene in the ratJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 1 2005Goran Westerberg Abstract The excretion and plasma kinetics of total radioactivity were studied following single oral administration of [3H]benzo[a]pyrene after multiple oral administration of ,-cyclodextrin at 0, 5, 50, or 500 mg/kg/day. The AUC and Cmax values in male and female rats following administration of [3H]benzo[a]pyrene in combination with 5 to 500 mg/kg ,-cyclodextrin were considerably lower than that in rats administered [3H]benzo[a]pyrene alone. At all dose levels of ,-cyclodextrin, the excretion of total radioactivity was almost entirely via feces, with <2% recovered in urine, demonstrating either that absorption of the orally administered dose was low or that, for any absorbed material, biliary excretion was the main route of excretion. However, following administration of vehicle, up to 5% of the administered radioactivity was recovered in the urine, suggesting that absorption may have been reduced by the presence of ,-cyclodextrin in the intestine. At all dose levels of ,-cyclodextrin, there was minimal retention of radioactivity in the carcase at the end of the collection period. ,-Cyclodextrin did not affect the apparent terminal half-life of radioactivity. Therefore, the reduced systemic exposure of rats to radioactivity in the presence of ,-cyclodextrin is likely related to a reduced oral bioavailability. © 2004 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 94:114,119, 2005 [source] Alcohol Up-Regulates TLR2 Through a NO/cGMP Dependent PathwayALCOHOLISM, Issue 1 2010Kristina L Bailey Background:, Heavy alcohol consumption is associated with severe bronchitis. This is likely related to increased inflammation in the airways of alcohol abusers. Toll-like receptor 2 (TLR2) is an important mediator of inflammation in the airway epithelium. TLR2 initiates an inflammatory cascade in response to gram-positive bacteria. We have previously shown that alcohol up-regulates TLR2 in the airway epithelium. However, the mechanism of alcohol-mediated up-regulation of TLR2 has not been identified. Methods:, A human airway epithelial cell line, 16HBE14o,, was exposed to biologically relevant concentrations of alcohol (100 mM) in the presence and absence of N, -Nitro- l -arginine methyl ester hydrochloride, a nitric oxide (NO) synthase inhibitor; and Rp-8-Br-cGMP-S, an antagonist analogue of cGMP. TLR2 was measured using real-time PCR and Western blots. In addition, 16HBE14o, cells were incubated with sodium nitroprusside (SNP), an NO donor, and 8-Br-cGMP, a cGMP analogue. TLR2 was measured using real-time PCR. Results:,N, -Nitro- l -arginine methyl ester hydrochloride blocked the alcohol-mediated up-regulation of TLR2. This indicates that NO plays a key role in alcohol's up-regulation of TLR2. SNP, a NO donor, up-regulated TLR2. Rp-8-Br-CGMP-S attenuated alcohol's up-regulation of TLR2, suggesting that NO was working through cGMP/PKG. 8-Br-cGMP up-regulated TLR2, also demonstrating the importance of cGMP/PKG. Conclusions:, Alcohol up-regulates TLR2 through a NO/cGMP/PKG dependent pathway in the airway epithelium. This is an important observation in the understanding how alcohol modulates airway inflammation. In addition, this is the first time that cyclic nucleotides have been shown to play a role in the regulation of TLR2. [source] Structural Analysis on Planar Defects Formed in WC Platelets in Ti-Doped WC,CoJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 10 2006Sabine Lay Platelet-reinforced WC,Co alloys are processed by liquid-phase sintering from very fine-grained WC powders in the presence of small amounts of TiC. Large and flat WC grains develop in the material. The microstructure of these platelets is investigated by high-resolution electron microscopy in order to obtain information on their formation mechanism. Inside the grains, an extended defect parallel to the basal plane is observed. It can be described by a pair of stacking faults with a shear vector equal to 1/3 ,0-110, occurring in two successive (0001) planes. At the level of the faults, the plane spacing is slightly reduced. The defect area is similar to a thin cubic layer about 0.5 nm thick at the interior of the platelet. The enhanced grain growth of the platelets is likely related to the presence of the defect area. [source] Head structures of Karoophasma sp. (Hexapoda, Mantophasmatodea) with phylogenetic implicationsJOURNAL OF ZOOLOGICAL SYSTEMATICS AND EVOLUTIONARY RESEARCH, Issue 2 2007E. Baum Abstract External and internal head structures of adults of Karoophasma sp. were examined and described. The results are compared with conditions found in other representatives of Mantophasmatodea and members of other lower neopteran groups. The X-shaped apodeme of the frons, the unpigmented oval area enclosed by apical branches of the anterior tentorial arms, the oval sclerotisation at the base of the labrum, the sclerotized rounded apical part of the galea, and the loss of M. labroepipharyngalis are probably autapomorphic for Mantophasmatodea. Plesiomorphic features (groundplan of Neoptera) are the orthognathous condition, the absence of parietal ridges, the absence of a gula, the absence of a ,perforation of the corpotentorium', the multisegmented antennae inserted between the compound eyes, the general arrangement of the mouthparts, the shape and composition of the maxillae and labium, and the nearly complete set of muscles. The presence of a transverse muscle connecting the antennal ampullae is a potential synapomorphy of Orthoptera, Phasmatodea and Dictyoptera. Character states suggesting affinities with Grylloblattodea are the absence of ocelli, the elongation of the corpotentorium, and the very similar mandibles with widely separated bases and completely reduced molae. Whether predacious habits are a synapomorphic feature of Mantophasmatodea and Grylloblattodea is uncertain. The retained orthognathous condition in Mantophasmatodea and Mantodea is likely related with different specialized preying techniques in both groups, i.e. rapid forward pushes of the head,prothorax complex, and the use of raptorial legs, respectively. Zusammenfassung Äußere und innere Kopfstrukturen von Imagines von Karoophasma sp. wurden untersucht und beschrieben. Die Ergebnisse wurden mit Befunden bei anderen Vetretern der Mantophasmatodea und bei potentiell nah verwandten Gruppen verglichen. Das x-förmige Frontalapodem, die unpigmentierten, von apikalen Ausläufern der vorderen Tentorialarme abgegrenzten ovalen Felder, die ovale Sklerotisation an der Basis des Labrum, der sklerotisierte, abgerundete Apikalteil der Galea und der Verlust von M. labroepipharyngalis sind wahrscheinlich Autapomorphien der Mantophasmatodea. Plesiomorphe Merkmale (Grundplan der Neoptera) sind die Orthognathie, das Fehlen von Parietalleisten, einer Gula und einer ,Perforation des Corpotentorium', die zwischen den Komplexaugen inserierenden vielgliedrigen Antennen, die Anordnung der Mundwerkzeuge, die Form und Zusammensetzung der Maxillen und des Labiums, und der nahezu vollständige Satz von Kopfmuskeln. Das Vorhandensein eines transversalen Muskels, der die Antennenampullen verbindet, ist eine potentielle Synapomorphie der Orthoptera, Phasmatodea und Dictyoptera. Er fehlt bei den Mantophasmatodea. Apomorphe Merkmale, die ein Schwestergruppenverhältnis mit den Grylloblattodea nahelegen, sind das Fehlen von Ocellen, die Verlängerung des Corpotentorium und die sehr ähnlichen, an der Basis weit voneinander getrennten Mandibeln ohne Mola. Ob die räuberische Lebensweise der Mantophasmatodea und Grylloblattodea eine Synapomorphie darstellt, ist unklar. Die bei den Mantophasmatodea und Mantodea beibehaltene Orthognathie ist wahrscheinlich bei beiden Gruppen mit unterschiedlichen, spezialisierten Jagdtechniken korreliert, mit schnellen Vorstößen des Kopf,Prothorax,Komplexes einerseits, und mit dem Einsatz von spezialisierten Fangbeinen andererseits. [source] Non-impact origin of the crater-like structures in the Gilf Kebir area (Egypt): Implications for the geology of eastern SaharaMETEORITICS & PLANETARY SCIENCE, Issue 10 2008Letizia ORTI It has been previously suggested that they could be the result of meteoritic impacts. Here we outline the results of our geological and geophysical survey in the area. The proposed impact origin for these structures is not supported by our observations and analyses, and we suggest an alternative interpretation. The crater-like structures in Gilf Kebir area are likely related to endogenic processes typical of hydrothermal vent complexes in volcanic areas which may reflect the emplacement of subvolcanic intrusives. [source] Elevation of XPA protein level in testis tumor cells without increasing resistance to cisplatin or UV radiationMOLECULAR CARCINOGENESIS, Issue 8 2008Beate Köberle Abstract Most testicular germ cell tumors are curable using cisplatin-based chemotherapy, and cell lines from these tumors are unusually sensitive to cisplatin and other DNA-damaging agents. It has been suggested that this might be caused by a lower-than normal nucleotide excision repair (NER) activity. Previous studies found that cell lines from testicular germ cell tumors have on average about one-third the level of the NER protein XPA in comparison to cell lines from other tumors. We asked whether over-expression of XPA protein would alleviate the cellular sensitivity and increase the DNA repair capacity of a testis tumor cell line. Increasing XPA levels in 833K cells by 10-fold did not increase resistance to UV irradiation. XPA was localized to the cell nucleus in all cell lines, before and after exposure to UV-radiation. 833K cells were proficient in removing UV radiation-induced photoproducts from the genome and increased XPA did not enhance the rate of removal. Further, over-expressing functional XPA protein did not correlate with increased resistance of 833K testis tumor cells to cisplatin. Thus, although the amount of XPA in this testis tumor cell line is lower than normal, it is sufficient for NER in vivo. The relative sensitivity of testis tumor cells to cisplatin, UV radiation, and other DNA damaging agents is likely related not to NER capacity, but to other factors such as the integrity of the p53 pathway in these cells. © 2008 Wiley-Liss, Inc. [source] Lineage diversification and historical demography of a sky island salamander, Plethodon ouachitae, from the Interior HighlandsMOLECULAR ECOLOGY, Issue 24 2008DONALD B. SHEPARD Abstract Sky islands provide ideal opportunities for understanding how climatic changes associated with Pleistocene glacial cycles influenced species distributions, genetic diversification, and demography. The salamander Plethodon ouachitae is largely restricted to high-elevation, mesic forest on six major mountains in the Ouachita Mountains. Because these mountains are separated by more xeric, low-elevation valleys, the salamanders appear to be isolated on sky islands where gene flow among populations on different mountains may be restricted. We used DNA sequence data along with ecological niche modelling and coalescent simulations to test several hypotheses related to diversifications in sky island habitats. Our results revealed that P. ouachitae is composed of seven well-supported lineages structured across six major mountains. The species originated during the Late Pliocene, and lineage diversification occurred during the Middle Pleistocene in a stepping stone fashion with a cyclical pattern of dispersal to a new mountain followed by isolation and divergence. Diversification occurred primarily on an east,west axis, which is likely related to the east,west orientation of the Ouachita Mountains and the more favourable cooler and wetter environmental conditions on north slopes compared to south-facing slopes and valleys. All non-genealogical coalescent methods failed to detect significant population expansion in any lineages. Bayesian skyline plots showed relatively stable population sizes over time, but indicated a slight to moderate amount of population growth in all lineages starting approximately 10 000,12 000 years ago. Our results provide new insight into sky island diversifications from a previously unstudied region, and further demonstrate that climatic changes during the Pleistocene had profound effects on lineage diversification and demography, especially in species from environmentally sensitive habitats in montane regions. [source] | |||||||||||||||||||||||||