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Sample records for accumulating evidence implicating

  1. Sequential biases in accumulating evidence

    PubMed Central

    Huggins, Richard; Dogo, Samson Henry

    2015-01-01

    Whilst it is common in clinical trials to use the results of tests at one phase to decide whether to continue to the next phase and to subsequently design the next phase, we show that this can lead to biased results in evidence synthesis. Two new kinds of bias associated with accumulating evidence, termed ‘sequential decision bias’ and ‘sequential design bias’, are identified. Both kinds of bias are the result of making decisions on the usefulness of a new study, or its design, based on the previous studies. Sequential decision bias is determined by the correlation between the value of the current estimated effect and the probability of conducting an additional study. Sequential design bias arises from using the estimated value instead of the clinically relevant value of an effect in sample size calculations. We considered both the fixed‐effect and the random‐effects models of meta‐analysis and demonstrated analytically and by simulations that in both settings the problems due to sequential biases are apparent. According to our simulations, the sequential biases increase with increased heterogeneity. Minimisation of sequential biases arises as a new and important research area necessary for successful evidence‐based approaches to the development of science. © 2015 The Authors. Research Synthesis Methods Published by John Wiley & Sons Ltd. PMID:26626562

  2. Evidence of self organization in great Sumatra earthquake recurrence times: Implications for coupling of tidal forcing and tectonic stress accumulation

    NASA Astrophysics Data System (ADS)

    Tiwari, R. K.; Puli, K.

    2012-12-01

    We analyzed inter- event time series of earthquake activities (M≥ 5) of Sumatra region spanning over 1973 to 2009 using techniques of nonlinear dynamics. The earthquake data were taken from the USGS catalogue centered on latitude 3.240N and longitude 95.825E. As a first step, in our analyses we computed the rank order statistics which revealed mixed response of earthquake dynamics indicating distinct breaks in slope of the rank order. This suggests that earthquake dynamics in this region is partly unstable and partly "self-organized" with a random tail. Comparison of return maps of the earthquakes inter- event time series with those representing random, stochastic and chaotic processes shows a quasi-deterministic behavior of earthquake genesis in the region. We further assessed the dimensionality of earthquake-generating mechanisms using a nonlinear predictor technique on two dimensional phase portrait constructed by recurrence time series. The nonlinear forecasting analysis suggests that the earthquake processes in the Sumatra region evolve on a non-random low-dimensional chaotic plane. Further, "K2" Entropy revealed a coherent structure indicating the deterministic dynamical pattern. This analysis is consistent with "self-organized" processes which could be explained invoking earth's internal dynamics, where, impulsively derived interdependencies cascades through the stress generated by tectonic plate movement. Our results, however, do not preclude the role of coupling of the above self-organized system with tidal forcing. Evidence for such a coupling in this region exists as 'triggering force". Keywords: Sumatra Earthquakes, Quasi-deterministic, Stochastic, Chaotic, Self-organized, K2 entropy, Phase portrait.

  3. Evidence Accumulation in the Magnitude System

    PubMed Central

    Lambrechts, Anna; Walsh, Vincent; van Wassenhove, Virginie

    2013-01-01

    Perceptual interferences in the estimation of quantities (time, space and numbers) have been interpreted as evidence for a common magnitude system. However, if duration estimation has appears sensitive to spatial and numerical interferences, space and number estimation tend to be resilient to temporal manipulations. These observations question the relative contribution of each quantity in the elaboration of a representation in a common mental metric. Here, we elaborated a task in which perceptual evidence accumulated over time for all tested quantities (space, time and number) in order to match the natural requirement for building a duration percept. For this, we used a bisection task. Experimental trials consisted of dynamic dots of different sizes appearing progressively on the screen. Participants were asked to judge the duration, the cumulative surface or the number of dots in the display while the two non-target dimensions varied independently. In a prospective experiment, participants were informed before the trial which dimension was the target; in a retrospective experiment, participants had to attend to all dimensions and were informed only after a given trial which dimension was the target. Surprisingly, we found that duration was resilient to spatial and numerical interferences whereas space and number estimation were affected by time. Specifically, and counter-intuitively, results revealed that longer durations lead to smaller number and space estimates whether participants knew before (prospectively) or after (retrospectively) a given trial which quantity they had to estimate. Altogether, our results support a magnitude system in which perceptual evidence for time, space and numbers integrate following Bayesian cue-combination rules. PMID:24339998

  4. Evidence of aluminium accumulation in aluminium welders.

    PubMed Central

    Elinder, C G; Ahrengart, L; Lidums, V; Pettersson, E; Sjögren, B

    1991-01-01

    Using atomic absorption spectrometry the aluminium concentrations in blood and urine and in two iliac bone biopsies obtained from welders with long term exposure to fumes containing aluminium were measured. The urinary excretion of two workers who had welded for 20 and 21 years varied between 107 and 351 micrograms Al/l, more than 10 times the concentration found in persons without occupational exposure. Urinary aluminium excretion remained high many years after stopping exposure. Blood and bone aluminium concentrations (4-53 micrograms Al/l and 18-29 micrograms Al/g respectively) were also raised but not to the same extent as urine excretion. It is concluded that long term exposure to aluminium by inhalation gives rise to accumulation of aluminium in the body and skeleton of health persons, and that the elimination of retained aluminium is very slow, in the order of several years. PMID:1954151

  5. Distinct relationships of parietal and prefrontal cortices to evidence accumulation

    PubMed Central

    Hanks, Timothy; Kopec, Charles D.; Brunton, Bingni W.; Duan, Chunyu A.; Erlich, Jeffrey C.; Brody, Carlos D.

    2014-01-01

    Gradual accumulation of evidence is thought to be fundamental for decision-making, and its neural correlates have been found in multiple brain regions1–8. Here we develop a generalizable method to measure tuning curves that specify the relationship between neural responses and mentally-accumulated evidence, and apply it to distinguish the encoding of decision variables in posterior parietal cortex (PPC) and prefrontal cortex (frontal orienting fields, FOF). We recorded the firing rates of neurons in PPC and FOF from rats performing a perceptual decision-making task. Classical analyses uncovered correlates of accumulating evidence, similar to previous observations in primates and also similar across the two regions. However, tuning curve assays revealed that while the PPC encodes a graded value of the accumulating evidence, the FOF has a more categorical encoding that indicates, throughout the trial, the decision provisionally favored by the evidence accumulated so far. Contrary to current views3,5,7–9, this suggests that premotor activity in frontal cortex does not play a role in the accumulation process, but instead has a more categorical function, such as transforming accumulated evidence into a discrete choice. To causally probe the role of FOF activity, we optogenetically silenced it during different timepoints of the trial. Consistent with a role in committing to a categorical choice at the end of the evidence accumulation process, but not consistent with a role during the accumulation itself, a behavioral effect was observed only when FOF silencing occurred at the end of the perceptual stimulus. Our results place important constraints on the circuit logic of brain regions involved in decision-making. PMID:25600270

  6. Evidence accumulation as a model for lexical selection.

    PubMed

    Anders, R; Riès, S; van Maanen, L; Alario, F X

    2015-11-01

    We propose and demonstrate evidence accumulation as a plausible theoretical and/or empirical model for the lexical selection process of lexical retrieval. A number of current psycholinguistic theories consider lexical selection as a process related to selecting a lexical target from a number of alternatives, which each have varying activations (or signal supports), that are largely resultant of an initial stimulus recognition. We thoroughly present a case for how such a process may be theoretically explained by the evidence accumulation paradigm, and we demonstrate how this paradigm can be directly related or combined with conventional psycholinguistic theory and their simulatory instantiations (generally, neural network models). Then with a demonstrative application on a large new real data set, we establish how the empirical evidence accumulation approach is able to provide parameter results that are informative to leading psycholinguistic theory, and that motivate future theoretical development. PMID:26375509

  7. Neural evidence accumulation persists after choice to inform metacognitive judgments

    PubMed Central

    Murphy, Peter R; Robertson, Ian H; Harty, Siobhán; O'Connell, Redmond G

    2015-01-01

    The ability to revise one’s certainty or confidence in a preceding choice is a critical feature of adaptive decision-making but the neural mechanisms underpinning this metacognitive process have yet to be characterized. In the present study, we demonstrate that the same build-to-threshold decision variable signal that triggers an initial choice continues to evolve after commitment, and determines the timing and accuracy of self-initiated error detection reports by selectively representing accumulated evidence that the preceding choice was incorrect. We also show that a peri-choice signal generated in medial frontal cortex provides a source of input to this post-decision accumulation process, indicating that metacognitive judgments are not solely based on the accumulation of feedforward sensory evidence. These findings impart novel insights into the generative mechanisms of metacognition. DOI: http://dx.doi.org/10.7554/eLife.11946.001 PMID:26687008

  8. Interference effects of choice on confidence: Quantum characteristics of evidence accumulation.

    PubMed

    Kvam, Peter D; Pleskac, Timothy J; Yu, Shuli; Busemeyer, Jerome R

    2015-08-25

    Decision-making relies on a process of evidence accumulation which generates support for possible hypotheses. Models of this process derived from classical stochastic theories assume that information accumulates by moving across definite levels of evidence, carving out a single trajectory across these levels over time. In contrast, quantum decision models assume that evidence develops over time in a superposition state analogous to a wavelike pattern and that judgments and decisions are constructed by a measurement process by which a definite state of evidence is created from this indefinite state. This constructive process implies that interference effects should arise when multiple responses (measurements) are elicited over time. We report such an interference effect during a motion direction discrimination task. Decisions during the task interfered with subsequent confidence judgments, resulting in less extreme and more accurate judgments than when no decision was elicited. These results provide qualitative and quantitative support for a quantum random walk model of evidence accumulation over the popular Markov random walk model. We discuss the cognitive and neural implications of modeling evidence accumulation as a quantum dynamic system. PMID:26261322

  9. Conscious and Nonconscious Processes:Distinct Forms of Evidence Accumulation?

    NASA Astrophysics Data System (ADS)

    Dehaene, Stanislas

    Among the many brain events evoked by a visual stimulus, which ones are associated specifically with conscious perception, and which merely reflect nonconscious processing? Understanding the neuronal mechanisms of consciousness is a major challenge for cognitive neuroscience. Recently, progress has been achieved by contrasting behavior and brain activation in minimally different experimental conditions, one of which leads to conscious perception whereas the other does not. This chapter reviews briefly this line of research and speculates on its theoretical interpretation. I propose to draw links between evidence accumulation models, which are highly successful in capturing elementary psychophysical decisions, and the conscious/nonconscious dichotomy. In this framework, conscious access would correspond to the crossing of a threshold in evidence accumulation within a distributed global workspace, a set of recurrently connected neurons with long axons that is able to integrate and broadcast back evidence from multiple brain processors. During nonconscious processing, evidence would be accumulated locally within specialized subcircuits, but would fail to reach the threshold needed for global ignition and, therefore, conscious reportability.

  10. Accumulation of trace elements by Pistia stratiotes: implications for phytoremediation.

    PubMed

    Odjegba, V J; Fasidi, I O

    2004-10-01

    The toxicity of eight potentially toxic trace elements (Ag, Cd, Cr, Cu, Hg, Ni, Pb and Zn) to Pistia stratiotes was examined to determine if this plant showed sufficient tolerance and metal accumulation to be used to phytoremediate waste water and/or natural water bodies polluted with these heavy metals. Young plants of equal size were grown hydroponically and amended with 0, 0.1, 0.3, 0.5, 1.0, 3.0 and 5.0 mM of each heavy metal individually for 21 days. Root elongation as well as emergence of new roots decreased significantly with increase in metal concentrations. The plant had the lowest and the highest tolerance indices for Hg and Zn respectively. The study indicated reduction in the rate of leaf expansion relative to metal type, their concentrations and the duration of exposure. A significant reduction in biomass production was observed in metal treated plants compared with the control plants. The relative growth rate of P. stratiotes was retarded by heavy metals under study. All trace elements accumulated to higher concentrations in root tissue rather than in shoot. Trace element accumulation in tissues and the bioconcentration factors were proportional to the initial concentration of individual metals in the growth medium and the duration of exposure. In terms of trace element removal, P. stratiotes presented differential accumulation and tolerance levels for different metals at similar treatment conditions. The implications of these results for phytoremediation are discussed. PMID:15673213

  11. Sorbitol accumulation in heart: Implication for diabetic cardiomyopathy

    SciTech Connect

    Nakada, Tustomu; Kwee, I.L. )

    1989-01-01

    Sorbitol levels in heart were determined in streptozotocin-induced diabetic rats. Significantly higher levels were found in hearts of diabetic rats compared to normal rats. The findings are compatible with either significantly higher de novo synthesis of sorbitol in heart than is generally believed or uptake of circulating sorbitol by heart as previously indicated by nuclear magnetic resonance (NMR) in vivo metabolic imaging. Sorbitol accumulation in heart tissue may play a role in the pathogenesis of diabetic cardiomyopathy as has been implicated in cataract formation.

  12. Auditory Streaming as an Online Classification Process with Evidence Accumulation

    PubMed Central

    Barniv, Dana; Nelken, Israel

    2015-01-01

    When human subjects hear a sequence of two alternating pure tones, they often perceive it in one of two ways: as one integrated sequence (a single "stream" consisting of the two tones), or as two segregated sequences, one sequence of low tones perceived separately from another sequence of high tones (two "streams"). Perception of this stimulus is thus bistable. Moreover, subjects report on-going switching between the two percepts: unless the frequency separation is large, initial perception tends to be of integration, followed by toggling between integration and segregation phases. The process of stream formation is loosely named “auditory streaming”. Auditory streaming is believed to be a manifestation of human ability to analyze an auditory scene, i.e. to attribute portions of the incoming sound sequence to distinct sound generating entities. Previous studies suggested that the durations of the successive integration and segregation phases are statistically independent. This independence plays an important role in current models of bistability. Contrary to this, we show here, by analyzing a large set of data, that subsequent phase durations are positively correlated. To account together for bistability and positive correlation between subsequent durations, we suggest that streaming is a consequence of an evidence accumulation process. Evidence for segregation is accumulated during the integration phase and vice versa; a switch to the opposite percept occurs stochastically based on this evidence. During a long phase, a large amount of evidence for the opposite percept is accumulated, resulting in a long subsequent phase. In contrast, a short phase is followed by another short phase. We implement these concepts using a probabilistic model that shows both bistability and correlations similar to those observed experimentally. PMID:26671774

  13. Auditory Streaming as an Online Classification Process with Evidence Accumulation.

    PubMed

    Barniv, Dana; Nelken, Israel

    2015-01-01

    When human subjects hear a sequence of two alternating pure tones, they often perceive it in one of two ways: as one integrated sequence (a single "stream" consisting of the two tones), or as two segregated sequences, one sequence of low tones perceived separately from another sequence of high tones (two "streams"). Perception of this stimulus is thus bistable. Moreover, subjects report on-going switching between the two percepts: unless the frequency separation is large, initial perception tends to be of integration, followed by toggling between integration and segregation phases. The process of stream formation is loosely named "auditory streaming". Auditory streaming is believed to be a manifestation of human ability to analyze an auditory scene, i.e. to attribute portions of the incoming sound sequence to distinct sound generating entities. Previous studies suggested that the durations of the successive integration and segregation phases are statistically independent. This independence plays an important role in current models of bistability. Contrary to this, we show here, by analyzing a large set of data, that subsequent phase durations are positively correlated. To account together for bistability and positive correlation between subsequent durations, we suggest that streaming is a consequence of an evidence accumulation process. Evidence for segregation is accumulated during the integration phase and vice versa; a switch to the opposite percept occurs stochastically based on this evidence. During a long phase, a large amount of evidence for the opposite percept is accumulated, resulting in a long subsequent phase. In contrast, a short phase is followed by another short phase. We implement these concepts using a probabilistic model that shows both bistability and correlations similar to those observed experimentally.

  14. Ultrastructural evidence for iron accumulation within the tube of Vestimentiferan Ridgeia piscesae.

    PubMed

    Peng, Xiaotong; Zhou, Huaiyang; Yao, Huiqiang; Li, Jiangtao; Wu, Zijun

    2009-10-01

    This study reports on the accumulation of iron within the tube wall of the deep sea vent macro invertebrate Vestimentiferan Ridgeia piscesae collected from Juan de Fuca ridge. Combining an array of approaches including environmental scanning electron microscope (ESEM), electron probe micro-analysis (EPMA), X-ray microanalysis (EDS) and transmission electron microscope (TEM), we provide evidences for the influence of prokaryotic organisms on the accumulation of metals on and within the tube wall. Two types of iron-rich minerals such as iron oxides and framboidal pyrites are identified within or on the tube wall. Our results reveal the presence of prokaryotic organism is apparently responsible for the early accumulation of iron-rich minerals in the tube wall. The implications of the biomineralisation of iron in tube wall at hydrothermal vents are discussed. PMID:19199091

  15. Ultrastructural evidence for iron accumulation within the tube of Vestimentiferan Ridgeia piscesae.

    PubMed

    Peng, Xiaotong; Zhou, Huaiyang; Yao, Huiqiang; Li, Jiangtao; Wu, Zijun

    2009-10-01

    This study reports on the accumulation of iron within the tube wall of the deep sea vent macro invertebrate Vestimentiferan Ridgeia piscesae collected from Juan de Fuca ridge. Combining an array of approaches including environmental scanning electron microscope (ESEM), electron probe micro-analysis (EPMA), X-ray microanalysis (EDS) and transmission electron microscope (TEM), we provide evidences for the influence of prokaryotic organisms on the accumulation of metals on and within the tube wall. Two types of iron-rich minerals such as iron oxides and framboidal pyrites are identified within or on the tube wall. Our results reveal the presence of prokaryotic organism is apparently responsible for the early accumulation of iron-rich minerals in the tube wall. The implications of the biomineralisation of iron in tube wall at hydrothermal vents are discussed.

  16. Is There Neural Evidence for an Evidence Accumulation Process in Memory Decisions?

    PubMed Central

    van Vugt, Marieke K.; Beulen, Marijke A.; Taatgen, Niels A.

    2016-01-01

    Models of evidence accumulation have been very successful at describing human decision making behavior. Recent years have also seen the first reports of neural correlates of this accumulation process. However, these studies have mostly focused on perceptual decision making tasks, ignoring the role of additional cognitive processes like memory retrieval that are crucial in real-world decisions. In this study, we tried to find a neural signature of evidence accumulation during a recognition memory task. To do this, we applied a method we have successfully used to localize evidence accumulation in scalp EEG during a perceptual decision making task. This time, however, we applied it to intracranial EEG recordings, which provide a much higher spatial resolution. We identified several brain areas where activity ramps up over time, but these neural patterns do not appear to be modulated by behavioral variables such as the amount of available evidence or response time. This casts doubt on the idea of evidence accumulation as a general decision-making mechanism underlying different types of decisions. PMID:27014024

  17. What is value—accumulated reward or evidence?

    PubMed Central

    Friston, Karl; Adams, Rick; Montague, Read

    2012-01-01

    Why are you reading this abstract? In some sense, your answer will cast the exercise as valuable—but what is value? In what follows, we suggest that value is evidence or, more exactly, log Bayesian evidence. This implies that a sufficient explanation for valuable behavior is the accumulation of evidence for internal models of our world. This contrasts with normative models of optimal control and reinforcement learning, which assume the existence of a value function that explains behavior, where (somewhat tautologically) behavior maximizes value. In this paper, we consider an alternative formulation—active inference—that replaces policies in normative models with prior beliefs about the (future) states agents should occupy. This enables optimal behavior to be cast purely in terms of inference: where agents sample their sensorium to maximize the evidence for their generative model of hidden states in the world, and minimize their uncertainty about those states. Crucially, this formulation resolves the tautology inherent in normative models and allows one to consider how prior beliefs are themselves optimized in a hierarchical setting. We illustrate these points by showing that any optimal policy can be specified with prior beliefs in the context of Bayesian inference. We then show how these prior beliefs are themselves prescribed by an imperative to minimize uncertainty. This formulation explains the saccadic eye movements required to read this text and defines the value of the visual sensations you are soliciting. PMID:23133414

  18. What is value-accumulated reward or evidence?

    PubMed

    Friston, Karl; Adams, Rick; Montague, Read

    2012-01-01

    Why are you reading this abstract? In some sense, your answer will cast the exercise as valuable-but what is value? In what follows, we suggest that value is evidence or, more exactly, log Bayesian evidence. This implies that a sufficient explanation for valuable behavior is the accumulation of evidence for internal models of our world. This contrasts with normative models of optimal control and reinforcement learning, which assume the existence of a value function that explains behavior, where (somewhat tautologically) behavior maximizes value. In this paper, we consider an alternative formulation-active inference-that replaces policies in normative models with prior beliefs about the (future) states agents should occupy. This enables optimal behavior to be cast purely in terms of inference: where agents sample their sensorium to maximize the evidence for their generative model of hidden states in the world, and minimize their uncertainty about those states. Crucially, this formulation resolves the tautology inherent in normative models and allows one to consider how prior beliefs are themselves optimized in a hierarchical setting. We illustrate these points by showing that any optimal policy can be specified with prior beliefs in the context of Bayesian inference. We then show how these prior beliefs are themselves prescribed by an imperative to minimize uncertainty. This formulation explains the saccadic eye movements required to read this text and defines the value of the visual sensations you are soliciting.

  19. Action Planning and the Timescale of Evidence Accumulation.

    PubMed

    Tsetsos, Konstantinos; Pfeffer, Thomas; Jentgens, Pia; Donner, Tobias H

    2015-01-01

    Perceptual decisions are based on the temporal integration of sensory evidence for different states of the outside world. The timescale of this integration process varies widely across behavioral contexts and individuals, and it is diagnostic for the underlying neural mechanisms. In many situations, the decision-maker knows the required mapping between perceptual evidence and motor response (henceforth termed "sensory-motor contingency") before decision formation. Here, the integrated evidence can be directly translated into a motor plan and, indeed, neural signatures of the integration process are evident as build-up activity in premotor brain regions. In other situations, however, the sensory-motor contingencies are unknown at the time of decision formation. We used behavioral psychophysics and computational modeling to test if knowledge about sensory-motor contingencies affects the timescale of perceptual evidence integration. We asked human observers to perform the same motion discrimination task, with or without trial-to-trial variations of the mapping between perceptual choice and motor response. When the mapping varied, it was either instructed before or after the stimulus presentation. We quantified the timescale of evidence integration under these different sensory-motor mapping conditions by means of two approaches. First, we analyzed subjects' discrimination threshold as a function of stimulus duration. Second, we fitted a dynamical decision-making model to subjects' choice behavior. The results from both approaches indicated that observers (i) integrated motion information for several hundred ms, (ii) used a shorter than optimal integration timescale, and (iii) used the same integration timescale under all sensory-motor mappings. We conclude that the mechanisms limiting the timescale of perceptual decisions are largely independent from long-term learning (under fixed mapping) or rapid acquisition (under variable mapping) of sensory-motor contingencies

  20. Loess is the accumulation of dust, not evidence for aridity

    NASA Astrophysics Data System (ADS)

    Zech, Roland

    2013-04-01

    Loess-paleosol sequences (LPS) are valuable terrestrial archives for Quaternary climate and environmental changes. The famous sections on the Chinese Loess Plateau, for example, document the alternation of warm and humid interglacials (paleosols) and cold and more arid glacials (loess). This, at least partly, reflects the weakening of the monsoonal circulation during glacials and has led to the notion that loess in general documents more arid conditions. Paleosols, on the other hand, are often interpreted to document more humid conditions. We studied the LPS Crvenka in the Carpathian Basin, southeast Europe, which spans the full last glacial cycle, and obtained results that do not fit the above concept: (i) The analysis of plant-derived long-chain n-alkanes indicates the presence of deciduous trees and shrubs during glacials, i.e. sufficient precipitation for tree growth, whereas tree-less grass steppes seem to have prevailed during the Eemian, the last interglacial. (ii) Compound-specific deuterium analyses on the alkanes show only little changes on glacial-interglacial timescale. When compared with the isotopic enrichment of the Mediterranean Sea during the last glacial, this likely documents a combination of increased rainfall, reduced evapo-transpiration and reduced temperatures. (iii) Novel lipid biomarkers derived from soil bacteria (GDGTs, glycerol dialkyl glycerol tetraethers) also indicate humid glacials (BIT index close to 1) and more arid interglacials (BIT<0.8). Our results are in good agreement with modelling studies suggesting a southward shift of the westerlies during glacials, and aridization in the Mediterranean area in response to man-made global warming. More importantly, they remind us of an important fact: Loess is the accumulation of dust, but not (necessarily) evidence for aridity. Pedogenesis may simply not have been able to keep pace with high glacial dust accumulation rates related to intense glacial, periglacial and fluvial activity

  1. Childhood adversities and psychosis: evidence, challenges, implications

    PubMed Central

    Morgan, Craig; Gayer‐Anderson, Charlotte

    2016-01-01

    There is a substantial body of research reporting evidence of associations between various forms of childhood adversity and psychosis, across the spectrum from experiences to disorder. This has been extended, more recently, to include studies of cumulative effects, of interactions with other factors, of specific effects, and of putative biological and psychological mechanisms. In this paper we evaluate this research and highlight the remaining methodological issues and gaps that temper, but do not dismiss, conclusions about the causal role of childhood adversity. We also consider the emerging work on cumulative, synergistic, and specific effects and on mechanisms; and discuss the broader implications of this line of research for our understanding of psychosis. We conclude that the current balance of evidence is that childhood adversities – particularly exposure to multiple adversities involving hostility and threat – do, in some people, contribute to the onset of psychotic experiences and psychotic disorders. PMID:27265690

  2. Evidence Accumulation and Choice Maintenance Are Dissociated in Human Perceptual Decision Making.

    PubMed

    Pedersen, Mads Lund; Endestad, Tor; Biele, Guido

    2015-01-01

    Perceptual decision making in monkeys relies on decision neurons, which accumulate evidence and maintain choices until a response is given. In humans, several brain regions have been proposed to accumulate evidence, but it is unknown if these regions also maintain choices. To test if accumulator regions in humans also maintain decisions we compared delayed and self-paced responses during a face/house discrimination decision making task. Computational modeling and fMRI results revealed dissociated processes of evidence accumulation and decision maintenance, with potential accumulator activations found in the dorsomedial prefrontal cortex, right inferior frontal gyrus and bilateral insula. Potential maintenance activation spanned the frontal pole, temporal gyri, precuneus and the lateral occipital and frontal orbital cortices. Results of a quantitative reverse inference meta-analysis performed to differentiate the functions associated with the identified regions did not narrow down potential accumulation regions, but suggested that response-maintenance might rely on a verbalization of the response. PMID:26510176

  3. Evidence Accumulation and Choice Maintenance Are Dissociated in Human Perceptual Decision Making.

    PubMed

    Pedersen, Mads Lund; Endestad, Tor; Biele, Guido

    2015-01-01

    Perceptual decision making in monkeys relies on decision neurons, which accumulate evidence and maintain choices until a response is given. In humans, several brain regions have been proposed to accumulate evidence, but it is unknown if these regions also maintain choices. To test if accumulator regions in humans also maintain decisions we compared delayed and self-paced responses during a face/house discrimination decision making task. Computational modeling and fMRI results revealed dissociated processes of evidence accumulation and decision maintenance, with potential accumulator activations found in the dorsomedial prefrontal cortex, right inferior frontal gyrus and bilateral insula. Potential maintenance activation spanned the frontal pole, temporal gyri, precuneus and the lateral occipital and frontal orbital cortices. Results of a quantitative reverse inference meta-analysis performed to differentiate the functions associated with the identified regions did not narrow down potential accumulation regions, but suggested that response-maintenance might rely on a verbalization of the response.

  4. The accumulated evidence on lung cancer and environmental tobacco smoke.

    PubMed Central

    Hackshaw, A. K.; Law, M. R.; Wald, N. J.

    1997-01-01

    OBJECTIVE: To estimate the risk of lung cancer in lifelong non-smokers exposed to environmental tobacco smoke. DESIGN: Analysis of 37 published epidemiological studies of the risk of lung cancer (4626 cases) in non-smokers who did and did not live with a smoker. The risk estimate was compared with that from linear extrapolation of the risk in smokers using seven studies of biochemical markers of tobacco smoke intake. MAIN OUTCOME MEASURE: Relative risk of lung cancer in lifelong non-smokers according to whether the spouse currently smoked or had never smoked. RESULTS: The excess risk of lung cancer was 24% (95% confidence interval 13% to 36%) in non-smokers who lived with a smoker (P < 0.001). Adjustment for the effects of bias (positive and negative) and dietary confounding had little overall effect; the adjusted excess risk was 26% (7% to 47%). The dose-response relation of the risk of lung cancer with both the number of cigarettes smoked by the spouse and the duration of exposure was significant. The excess risk derived by linear extrapolation from that in smokers was 19%, similar to the direct estimate of 26%. CONCLUSION: The epidemiological and biochemical evidence on exposure to environmental tobacco smoke, with the supporting evidence of tobacco specific carcinogens in the blood and urine of non-smokers exposed to environmental tobacco smoke, provides compelling confirmation that breathing other people's tobacco smoke is a cause of lung cancer. PMID:9365295

  5. Perception as Evidence Accumulation and Bayesian Inference: Insights from Masked Priming

    ERIC Educational Resources Information Center

    Norris, Dennis; Kinoshita, Sachiko

    2008-01-01

    The authors argue that perception is Bayesian inference based on accumulation of noisy evidence and that, in masked priming, the perceptual system is tricked into treating the prime and the target as a single object. Of the 2 algorithms considered for formalizing how the evidence sampled from a prime and target is combined, only 1 was shown to be…

  6. Rhythmic fluctuations in evidence accumulation during decision making in the human brain

    PubMed Central

    Wyart, Valentin; de Gardelle, Vincent; Scholl, Jacqueline; Summerfield, Christopher

    2014-01-01

    Summary Categorical choices are preceded by the accumulation of sensory evidence in favour of one action or another. Current models describe evidence accumulation as a continuous process occurring at a constant rate, but this view is inconsistent with accounts of a psychological refractory period during sequential information processing. During multi-sample perceptual categorisation, we found that the neural encoding of momentary evidence in human electrical brain signals and its subsequent impact on choice fluctuated rhythmically according to the phase of ongoing parietal delta oscillations (1-3 Hz). By contrast, lateralised beta-band power (10-30 Hz) overlying human motor cortex encoded the integrated evidence as a response preparation signal. These findings draw a clear distinction between central and motor stages of perceptual decision making, with successive samples of sensory evidence competing to pass through a serial processing bottleneck before being mapped onto action. PMID:23177968

  7. Coverage with evidence development: ethical issues and policy implications.

    PubMed

    Miller, Franklin G; Pearson, Steven D

    2008-07-01

    Coverage with evidence development (CED) is an evolving method of providing provisional access to novel medical interventions while generating the evidence needed to determine whether unconditional coverage is warranted. In this article we review the policy rationale for CED and present a normative analysis that addresses ethical concerns and policy implications.

  8. Mobility of water ice on Callisto - Evidence and implications

    NASA Technical Reports Server (NTRS)

    Spencer, J. R.; Maloney, P. R.

    1984-01-01

    Voyager images of Callisto reveal evidence for the accumulation of a bright volatile, presumably water ice, on north-facing slopes in the north polar region. The geometry of these accumulations suggests that ice migration in Callistoan high latitudes is dominated by thermal sublimation, controlled by insolation-dependent surface temperature contrasts. Such sublimation-dominated migration may result in the cold-trapping of most of the surface ice in discrete high-albedo regions.

  9. Error awareness as evidence accumulation: effects of speed-accuracy trade-off on error signaling

    PubMed Central

    Steinhauser, Marco; Yeung, Nick

    2012-01-01

    Errors in choice tasks have been shown to elicit a cascade of characteristic components in the human event-related potential (ERPs)—the error-related negativity (Ne/ERN) and the error positivity (Pe). Despite the large number of studies concerned with these components, it is still unclear how they relate to error awareness as measured by overt error signaling responses. In the present study, we considered error awareness as a decision process in which evidence for an error is accumulated until a decision criterion is reached, and hypothesized that the Pe is a correlate of the accumulated decision evidence. To test the prediction that the amplitude of the Pe varies as a function of the strength and latency of the accumulated evidence for an error, we manipulated the speed-accuracy trade-off (SAT) in a brightness discrimination task while participants signaled the occurrence of errors. Based on a previous modeling study, we predicted that lower speed pressure should be associated with weaker evidence for an error and, thus, with smaller Pe amplitudes. As predicted, average Pe amplitude was decreased and error signaling was impaired in a low speed pressure condition compared to a high speed pressure condition. In further analyses, we derived single-trial Pe amplitudes using a logistic regression approach. Single-trial amplitudes robustly predicted the occurrence of signaling responses on a trial-by-trial basis. These results confirm the predictions of the evidence accumulation account, supporting the notion that the Pe reflects accumulated evidence for an error and that this evidence drives the emergence of error awareness. PMID:22905027

  10. Hypertension: empirical evidence and implications in 2014.

    PubMed

    Makridakis, Spyros; DiNicolantonio, James J

    2014-01-01

    High blood pressure (HBP) or hypertension (HTN) is one of the leading causes of cardiovascular (CV) morbidity and mortality throughout the world. Despite this fact, there is widespread agreement that the treatment of HBP, over the last half century, has been a great achievement. However, after the release of the new Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure-8 (JNC-8) guidelines, there have been heated debates with regard to what are the most evidence-based blood pressure goals. While JNC-8 claims that the goal blood pressure for otherwise healthy patients with mild hypertension (systolic blood pressure ≥140-159 mm Hg and diastolic blood pressure ≥90-99 mm Hg) should be <140/90 mm Hg; a recent Cochrane meta-analysis is in direct conflict with these recommendations. Indeed, a 2012 Cochrane meta-analysis indicated that there is no evidence that treating otherwise healthy mild hypertension patients with antihypertensive therapy will reduce CV events or mortality. Additionally, the Cochrane meta-analysis showed that antihypertensive therapy was associated with a significant increase in withdrawal due to adverse events. Thus, the current evidence in the literature does not support the goals set by the JNC-8 guidelines. In this review we discussed the strengths and limitations of both lines of evidence and why it takes an evidence-based medication to reduce CV events/mortality (eg, how a goal blood pressure is achieved is more important than getting to the goal). As medications inherently cause side effects and come at a cost to the patient, the practice of evidence-based medicine becomes exceedingly important. Although the majority of HTN studies claim great advantages by lowering HBP, this review finds severe conflicts in the findings among the various HTN studies, as well as serious epistemological, methodological and statistical problems that cast doubt to such claims. PMID:25332797

  11. Evidence Based Research: Implications for Counselor Educators.

    ERIC Educational Resources Information Center

    Bartley, Amy E.; Biles, Kathy E.; Low, Lori L.; Nakazawa-Hewitt, M.; Windish, Bonnie L.

    For the past decade, the practice of evidence based research (EBR) in treatment decisions has been a standard in the medical field, and is quickly becoming a standard of practice in other human service fields. Counselor educators are faced with the necessity to begin to implement EBR into their teaching and scholarship, but have limited knowledge…

  12. Evidence accumulation in a complex task: Making choices about concurrent multiattribute stimuli under time pressure.

    PubMed

    Palada, Hector; Neal, Andrew; Vuckovic, Anita; Martin, Russell; Samuels, Kate; Heathcote, Andrew

    2016-03-01

    Evidence accumulation models transform observed choices and associated response times into psychologically meaningful constructs such as the strength of evidence and the degree of caution. Standard versions of these models were developed for rapid (∼1 s) choices about simple stimuli, and have recently been elaborated to some degree to address more complex stimuli and response methods. However, these elaborations can be difficult to use with designs and measurements typically encountered in complex applied settings. We test the applicability of 2 standard accumulation models-the diffusion (Ratcliff & McKoon, 2008) and the linear ballistic accumulation (LBA) (Brown & Heathcote, 2008)-to data from a task representative of many applied situations: the detection of heterogeneous multiattribute targets in a simulated unmanned aerial vehicle (UAV) operator task. Despite responses taking more than 2 s and complications added by realistic features, such as a complex target classification rule, interruptions from a simultaneous UAV navigation task, and time pressured choices about several concurrently present potential targets, these models performed well descriptively. They also provided a coherent psychological explanation of the effects of decision uncertainty and workload manipulations. Our results support the wider application of standard evidence accumulation models to applied decision-making settings. PMID:26844369

  13. Evidence accumulation in a complex task: Making choices about concurrent multiattribute stimuli under time pressure.

    PubMed

    Palada, Hector; Neal, Andrew; Vuckovic, Anita; Martin, Russell; Samuels, Kate; Heathcote, Andrew

    2016-03-01

    Evidence accumulation models transform observed choices and associated response times into psychologically meaningful constructs such as the strength of evidence and the degree of caution. Standard versions of these models were developed for rapid (∼1 s) choices about simple stimuli, and have recently been elaborated to some degree to address more complex stimuli and response methods. However, these elaborations can be difficult to use with designs and measurements typically encountered in complex applied settings. We test the applicability of 2 standard accumulation models-the diffusion (Ratcliff & McKoon, 2008) and the linear ballistic accumulation (LBA) (Brown & Heathcote, 2008)-to data from a task representative of many applied situations: the detection of heterogeneous multiattribute targets in a simulated unmanned aerial vehicle (UAV) operator task. Despite responses taking more than 2 s and complications added by realistic features, such as a complex target classification rule, interruptions from a simultaneous UAV navigation task, and time pressured choices about several concurrently present potential targets, these models performed well descriptively. They also provided a coherent psychological explanation of the effects of decision uncertainty and workload manipulations. Our results support the wider application of standard evidence accumulation models to applied decision-making settings.

  14. Evaluation of zinc accumulation, allocation, and tolerance in Zea mays L. seedlings: implication for zinc phytoextraction.

    PubMed

    Bashmakov, Dmitry I; Lukatkin, Alexander S; Anjum, Naser A; Ahmad, Iqbal; Pereira, Eduarda

    2015-10-01

    This work investigated the accumulation, allocation, and impact of zinc (Zn; 1.0 μM-10 mM) in maize (Zea mays L.) seedlings under simulated laboratory conditions. Z. mays exhibited no significant change in its habitus (the physical characteristics of plants) up to 10-1000 μM of Zn (vs 5-10 mM Zn). Zn tolerance evaluation, based on the root test, indicated a high tolerance of Z. mays to both low and intermediate (or relatively high) concentrations of Zn, whereas this plant failed to tolerate 10 mM Zn and exhibited a 5-fold decrease in its Zn tolerance. Contingent to Zn treatment levels, Zn hampered the growth of axial organs and brought decreases in the leaf area, water regime, and biomass accumulation. Nevertheless, at elevated levels of Zn (10 mM), Zn(2+) was stored in the root cytoplasm and inhibited both axial organ growth and water regime. However, accumulation and allocation of Zn in Z. mays roots, studied herein employing X-ray fluorimeter and histochemical methods, were close to Zn accumulator plants. Overall, the study outcomes revealed Zn tolerance of Z. mays, and also implicate its potential role in Zn phytoextraction.

  15. Incorporation of radiometric tracers in peat and implications for estimating accumulation rates.

    PubMed

    Hansson, Sophia V; Kaste, James M; Olid, Carolina; Bindler, Richard

    2014-09-15

    Accurate dating of peat accumulation is essential for quantitatively reconstructing past changes in atmospheric metal deposition and carbon burial. By analyzing fallout radionuclides (210)Pb, (137)Cs, (241)Am, and (7)Be, and total Pb and Hg in 5 cores from two Swedish peatlands we addressed the consequence of estimating accumulation rates due to downwashing of atmospherically supplied elements within peat. The detection of (7)Be down to 18-20 cm for some cores, and the broad vertical distribution of (241)Am without a well-defined peak, suggest some downward transport by percolating rainwater and smearing of atmospherically deposited elements in the uppermost peat layers. Application of the CRS age-depth model leads to unrealistic peat mass accumulation rates (400-600 g m(-2) yr(-1)), and inaccurate estimates of past Pb and Hg deposition rates and trends, based on comparisons to deposition monitoring data (forest moss biomonitoring and wet deposition). After applying a newly proposed IP-CRS model that assumes a potential downward transport of (210)Pb through the uppermost peat layers, recent peat accumulation rates (200-300 g m(-2) yr(-1)) comparable to published values were obtained. Furthermore, the rates and temporal trends in Pb and Hg accumulation correspond more closely to monitoring data, although some off-set is still evident. We suggest that downwashing can be successfully traced using (7)Be, and if this information is incorporated into age-depth models, better calibration of peat records with monitoring data and better quantitative estimates of peat accumulation and past deposition are possible, although more work is needed to characterize how downwashing may vary between seasons or years.

  16. Sources of noise during accumulation of evidence in unrestrained and voluntarily head-restrained rats

    PubMed Central

    Scott, Benjamin B; Constantinople, Christine M; Erlich, Jeffrey C; Tank, David W; Brody, Carlos D

    2015-01-01

    Decision-making behavior is often characterized by substantial variability, but its source remains unclear. We developed a visual accumulation of evidence task designed to quantify sources of noise and to be performed during voluntary head restraint, enabling cellular resolution imaging in future studies. Rats accumulated discrete numbers of flashes presented to the left and right visual hemifields and indicated the side that had the greater number of flashes. Using a signal-detection theory-based model, we found that the standard deviation in their internal estimate of flash number scaled linearly with the number of flashes. This indicates a major source of noise that, surprisingly, is not consistent with the widely used 'drift-diffusion modeling' (DDM) approach but is instead closely related to proposed models of numerical cognition and counting. We speculate that this form of noise could be important in accumulation of evidence tasks generally. DOI: http://dx.doi.org/10.7554/eLife.11308.001 PMID:26673896

  17. The nitrogen legacy: emerging evidence of nitrogen accumulation in anthropogenic landscapes

    NASA Astrophysics Data System (ADS)

    Van Meter, K. J.; Basu, N. B.; Veenstra, J. J.; Burras, C. L.

    2016-03-01

    Watershed and global-scale nitrogen (N) budgets indicate that the majority of the N surplus in anthropogenic landscapes does not reach the coastal oceans. While there is general consensus that this ‘missing’ N either exits the landscape via denitrification or is retained within watersheds as nitrate or organic N, the relative magnitudes of these pools and fluxes are subject to considerable uncertainty. Our study, for the first time, provides direct, large-scale evidence of N accumulation in the root zones of agricultural soils that may account for much of the ‘missing N’ identified in mass balance studies. We analyzed long-term soil data (1957-2010) from 2069 sites throughout the Mississippi River Basin (MRB) to reveal N accumulation in cropland of 25-70 kg ha-1 yr-1, a total of 3.8 ± 1.8 Mt yr-1 at the watershed scale. We then developed a simple modeling framework to capture N depletion and accumulation dynamics under intensive agriculture. Using the model, we show that the observed accumulation of soil organic N (SON) in the MRB over a 30 year period (142 Tg N) would lead to a biogeochemical lag time of 35 years for 99% of legacy SON, even with complete cessation of fertilizer application. By demonstrating that agricultural soils can act as a net N sink, the present work makes a critical contribution towards the closing of watershed N budgets.

  18. Implication of eolian delivery and accumulation of highly reactive iron to the Atlantic Ocean

    NASA Astrophysics Data System (ADS)

    Lee, B. K.; Owens, J. D.; Lyons, T. W.

    2014-12-01

    Iron, although abundant in the Earth's crust, is present at low concentrations in sea water and is a limiting nutrient for phytoplankton. Eolian dust (loess) is a major source of this micronutrient, and its deposition has important implications for the global CO2 budget. In this study, we explore distributions of potentially bioreactive Fe, the soluble fraction required by phytoplankton for photosynthesis and nitrogen assimilation, in deep-sea sediments in the North and South Atlantic Oceans. We used a state-of-the-art Fe speciation technique to characterize Fe inputs from different source regions, specifically North Africa and Patagonia to address the patterns and implications across glacial-interglacial time scales. In many open-ocean regions the input of new iron to the surface waters is dominated by the atmospheric deposition of soluble iron in eolian dusts. Multiple records have shown dust accumulation is correlated with glacial-interglacial cycles - glacial periods are substantially dustier. Furthermore, the delivery of eolian dust to the North and South Atlantic Oceans are from two very different source regions and soil types. We analyzed IODP cores from these two regions and our preliminary data shows similar pattern of iron distribution from both the North and South Atlantic Oceans. To date we have found no simple global pattern of bioavailable iron distribution during glacial and interglacial periods. We have analyzed a range of size distributions to isolate the dust-dominated fraction and the data shows no size effects in bioavailable form of iron distribution. We will explore the role of deep-water dust dissolution and sedimentary redox implications and its role on the bioreactive Fe record in marine cores.

  19. Cognitive contributions to gait and falls: evidence and implications.

    PubMed

    Amboni, Marianna; Barone, Paolo; Hausdorff, Jeffrey M

    2013-09-15

    Dementia and gait impairments often coexist in older adults and patients with neurodegenerative disease. Both conditions represent independent risk factors for falls. The relationship between cognitive function and gait has recently received increasing attention. Gait is no longer considered merely automated motor activity but rather an activity that requires executive function and attention as well as judgment of external and internal cues. In this review, we intend to: (1) summarize and synthesize the experimental, neuropsychological, and neuroimaging evidence that supports the role played by cognition in the control of gait; and (2) briefly discuss the implications deriving from the interplay between cognition and gait. In recent years, the dual task paradigm has been widely used as an experimental method to explore the interplay between gait and cognition. Several neuropsychological investigations have also demonstrated that walking relies on the use of several cognitive domains, including executive-attentional function, visuospatial abilities, and even memory resources. A number of morphological and functional neuroimaging studies have offered additional evidence supporting the relationship between gait and cognitive resources. Based on the findings from 3 lines of studies, it appears that a growing body of evidence indicates a pivotal role of cognition in gait control and fall prevention. The interplay between higher-order neural function and gait has a number of clinical implications, ranging from integrated assessment tools to possible innovative lines of interventions, including cognitive therapy for falls prevention on one hand and walking program for reducing dementia risk on the other.

  20. Demystifying "free will": the role of contextual information and evidence accumulation for predictive brain activity.

    PubMed

    Bode, Stefan; Murawski, Carsten; Soon, Chun Siong; Bode, Philipp; Stahl, Jutta; Smith, Philip L

    2014-11-01

    Novel multivariate pattern classification analyses have enabled the prediction of decision outcomes from brain activity prior to decision-makers' reported awareness. These findings are often discussed in relation to the philosophical concept of "free will". We argue that these studies demonstrate the role of unconscious processes in simple free choices, but they do not inform the philosophical debate. Moreover, these findings are difficult to relate to cognitive decision-making models, due to misleading assumptions about random choices. We review evidence suggesting that sequential-sampling models, which assume accumulation of evidence towards a decision threshold, can also be applied to free decisions. If external evidence is eliminated by the task instructions, decision-makers might use alternative, subtle contextual information as evidence, such as their choice history, that is not consciously monitored and usually concealed by the experimental design. We conclude that the investigation of neural activity patterns associated with free decisions should aim to investigate how decisions are jointly a function of internal and external contexts, rather than to resolve the philosophical "free will" debate.

  1. Distinct effects of prefrontal and parietal cortex inactivations on an accumulation of evidence task in the rat

    PubMed Central

    Erlich, Jeffrey C; Brunton, Bingni W; Duan, Chunyu A; Hanks, Timothy D; Brody, Carlos D

    2015-01-01

    Numerous brain regions have been shown to have neural correlates of gradually accumulating evidence for decision-making, but the causal roles of these regions in decisions driven by accumulation of evidence have yet to be determined. Here, in rats performing an auditory evidence accumulation task, we inactivated the frontal orienting fields (FOF) and posterior parietal cortex (PPC), two rat cortical regions that have neural correlates of accumulating evidence and that have been proposed as central to decision-making. We used a detailed model of the decision process to analyze the effect of inactivations. Inactivation of the FOF induced substantial performance impairments that were quantitatively best described as an impairment in the output pathway of an evidence accumulator with a long integration time constant (>240 ms). In contrast, we found a minimal role for PPC in decisions guided by accumulating auditory evidence, even while finding a strong role for PPC in internally-guided decisions. DOI: http://dx.doi.org/10.7554/eLife.05457.001 PMID:25869470

  2. Chronic obstructive pulmonary disease exacerbations: latest evidence and clinical implications

    PubMed Central

    Qureshi, Hammad; Sharafkhaneh, Amir

    2014-01-01

    Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality worldwide and results in an economic and social burden that is both substantial and increasing. The natural history of COPD is punctuated by exacerbations which have major short- and long-term implications on the patient and healthcare system. Evidence-based guidelines stipulate that early detection and prompt treatment of exacerbations are essential to ensure optimal outcomes and to reduce the burden of COPD. Several factors can identify populations at risk of exacerbations. Implementing prevention measures in patients at risk is a major goal in the management of COPD. PMID:25177479

  3. Comparative functional characterization of eugenol synthase from four different Ocimum species: Implications on eugenol accumulation.

    PubMed

    Anand, Atul; Jayaramaiah, Ramesha H; Beedkar, Supriya D; Singh, Priyanka A; Joshi, Rakesh S; Mulani, Fayaj A; Dholakia, Bhushan B; Punekar, Sachin A; Gade, Wasudeo N; Thulasiram, Hirekodathakallu V; Giri, Ashok P

    2016-11-01

    Isoprenoids and phenylpropanoids are the major secondary metabolite constituents in Ocimum genus. Though enzymes from phenylpropanoid pathway have been characterized from few plants, limited information exists on how they modulate levels of secondary metabolites. Here, we performed phenylpropanoid profiling in different tissues from five Ocimum species, which revealed significant variations in secondary metabolites including eugenol, eugenol methyl ether, estragole and methyl cinnamate levels. Expression analysis of eugenol synthase (EGS) gene showed higher transcript levels especially in young leaves and inflorescence; and were positively correlated with eugenol contents. Additionally, transcript levels of coniferyl alcohol acyl transferase, a key enzyme diverting pool of substrate to phenylpropanoids, were in accordance with their abundance in respective species. In particular, eugenol methyl transferase expression positively correlated with higher levels of eugenol methyl ether in Ocimum tenuiflorum. Further, EGSs were functionally characterized from four Ocimum species varying in their eugenol contents. Kinetic and expression analyses indicated, higher enzyme turnover and transcripts levels, in species accumulating more eugenol. Moreover, biochemical and bioinformatics studies demonstrated that coniferyl acetate was the preferred substrate over coumaryl acetate when used, individually or together, in the enzyme assay. Overall, this study revealed the preliminary evidence for varied accumulation of eugenol and its abundance over chavicol in these Ocimum species. Current findings could potentially provide novel insights for metabolic modulations in medicinal and aromatic plants. PMID:27519164

  4. Comparative functional characterization of eugenol synthase from four different Ocimum species: Implications on eugenol accumulation.

    PubMed

    Anand, Atul; Jayaramaiah, Ramesha H; Beedkar, Supriya D; Singh, Priyanka A; Joshi, Rakesh S; Mulani, Fayaj A; Dholakia, Bhushan B; Punekar, Sachin A; Gade, Wasudeo N; Thulasiram, Hirekodathakallu V; Giri, Ashok P

    2016-11-01

    Isoprenoids and phenylpropanoids are the major secondary metabolite constituents in Ocimum genus. Though enzymes from phenylpropanoid pathway have been characterized from few plants, limited information exists on how they modulate levels of secondary metabolites. Here, we performed phenylpropanoid profiling in different tissues from five Ocimum species, which revealed significant variations in secondary metabolites including eugenol, eugenol methyl ether, estragole and methyl cinnamate levels. Expression analysis of eugenol synthase (EGS) gene showed higher transcript levels especially in young leaves and inflorescence; and were positively correlated with eugenol contents. Additionally, transcript levels of coniferyl alcohol acyl transferase, a key enzyme diverting pool of substrate to phenylpropanoids, were in accordance with their abundance in respective species. In particular, eugenol methyl transferase expression positively correlated with higher levels of eugenol methyl ether in Ocimum tenuiflorum. Further, EGSs were functionally characterized from four Ocimum species varying in their eugenol contents. Kinetic and expression analyses indicated, higher enzyme turnover and transcripts levels, in species accumulating more eugenol. Moreover, biochemical and bioinformatics studies demonstrated that coniferyl acetate was the preferred substrate over coumaryl acetate when used, individually or together, in the enzyme assay. Overall, this study revealed the preliminary evidence for varied accumulation of eugenol and its abundance over chavicol in these Ocimum species. Current findings could potentially provide novel insights for metabolic modulations in medicinal and aromatic plants.

  5. First evidence of accumulation in cyanobacteria of guanidinoacetate, a precursor of the toxin cylindrospermopsin.

    PubMed

    Barón-Sola, Ángel; Sanz-Alférez, Soledad; del Campo, Francisca F

    2015-01-01

    Guanidinoacetate (GAA) is one of the most extensively studied toxic guanidine compounds. Changes in GAA can affect the nervous system and induce hyperhomocysteinemia, representing a risk factor for cardiovascular diseases. In cyanobacteria, GAA is thought to be an intermediate in the synthesis of the toxin cylindrospermopsin (CYN), one of the most common known cyanotoxins that affects multiple organs and functions in animals and plants. In spite of the evidence supporting GAA toxicity and its role in CYN synthesis, no data have been reported on the accumulation of GAA in any cyanobacterium. We have analyzed and compared the content of GAA in cultures of diverse cyanobacteria types, both cylindrospermopsin producing (CYN(+)) and not producing (CYN(-)). The results obtained show that GAA accumulates in the majority of the strains tested, although the highest content was found in one of the CYN(+) strain, Aphanizomenon ovalisporum UAM-MAO. In this strain, both GAA and CYN can be located within and out the cells. In conclusion, GAA appears to be a general cyanobacterial metabolite that due to its proven toxic should be considered when studying and managing cyanobacteria toxicity.

  6. Evidence accumulation in decision making: unifying the "take the best" and the "rational" models.

    PubMed

    Lee, Michael D; Cummins, Tarrant D R

    2004-04-01

    An evidence accumulation model of forced-choice decision making is proposed to unify the fast and frugal take the best (TTB) model and the alternative rational (RAT) model with which it is usually contrasted. The basic idea is to treat the TTB model as a sequential-sampling process that terminates as soon as any evidence in favor of a decision is found and the rational approach as a sequential-sampling process that terminates only when all available information has been assessed. The unified TTB and RAT models were tested in an experiment in which participants learned to make correct judgments for a set of real-world stimuli on the basis of feedback, and were then asked to make additional judgments without feedback for cases in which the TTB and the rational models made different predictions. The results show that, in both experiments, there was strong intraparticipant consistency in the use of either the TTB or the rational model but large interparticipant differences in which model was used. The unified model is shown to be able to capture the differences in decision making across participants in an interpretable way and is preferred by the minimum description length model selection criterion.

  7. ART-EMAP: A neural network architecture for object recognition by evidence accumulation.

    PubMed

    Carpenter, G A; Ross, W D

    1995-01-01

    A new neural network architecture is introduced for the recognition of pattern classes after supervised and unsupervised learning. Applications include spatio-temporal image understanding and prediction and 3D object recognition from a series of ambiguous 2D views. The architecture, called ART-EMAP, achieves a synthesis of adaptive resonance theory (ART) and spatial and temporal evidence integration for dynamic predictive mapping (EMAP). ART-EMAP extends the capabilities of fuzzy ARTMAP in four incremental stages. Stage 1 introduces distributed pattern representation at a view category field. Stage 2 adds a decision criterion to the mapping between view and object categories, delaying identification of ambiguous objects when faced with a low confidence prediction. Stage 3 augments the system with a field where evidence accumulates in medium-term memory. Stage 4 adds an unsupervised learning process to fine-tune performance after the limited initial period of supervised network training. Each ART-EMAP stage is illustrated with a benchmark simulation example, using both noisy and noise-free data. PMID:18263371

  8. Mononuclear phagocyte accumulation in visceral tissue in HIV encephalitis: evidence for increased monocyte/macrophage trafficking and altered differentiation.

    PubMed

    Fischer, Tracy; Wyatt, Christina M; D'Agati, Vivette D; Croul, Sidney; McCourt, Laura; Morgello, Susan; Rappaport, Jay

    2014-01-01

    The invasion of circulating monocytes/macrophages (MΦ)s from the peripheral blood into the central nervous system (CNS) appears to play an important role in the pathogenesis of HIV dementia (HIV-D), the most severe form of HIV-associated neurocognitive disorders (HAND), often confirmed histologically as HIV encephalitis (HIVE). In order to determine if trafficking of monocytes/MΦs is exclusive to the CNS or if it also occurs in organs outside of the brain, we have focused our investigation on visceral tissues of patients with HIVE. Liver, lymph node, spleen, and kidney autopsy tissues from the same HIVE cases investigated in earlier studies were examined by immunohistochemistry for the presence of CD14, CD16, CD68, Ki-67, and HIV-1 p24 expression. Here, we report a statistically significant increase in accumulation of MΦs in kidney, spleen, and lymph node tissues in specimens from patients with HIVE. In liver, we did not observe a significant increase in parenchymal macrophage accumulation, although perivascular macrophage accumulation was consistently observed with nodular lesions in 4 of 5 HIVE cases. We also observed an absence of CD14 expression on splenic MΦs in HIVE cases, which may implicate the spleen as a potential source of increased plasma soluble CD14 in HIV infection. HIV-1 p24 expression was observed in liver, lymph node and spleen but not kidney. Interestingly, renal pathology suggestive of chronic tubulointerstitial nephritis (possibly due to chronic pyelonephritis), including tubulointerstitial scarring, chronic interstitial inflammation and focal global glomerulosclerosis, without evidence of HIV-associated nephropathy (HIVAN), was seen in four of eight HIVE cases. Focal segmental and global glomerulosclerosis with tubular dilatation and prominent interstitial inflammation, consistent with HIVAN, was observed in two of the eight cases. Abundant cells expressing monocyte/MΦ cell surface markers, CD14 and CD68, were also CD16(+) and found

  9. Organochlorine accumulation on a highly consumed bivalve (Scrobicularia plana) and its main implications for human health.

    PubMed

    Grilo, T F; Cardoso, P G; Pato, P; Duarte, A C; Pardal, M A

    2013-09-01

    Contamination by polychlorinated biphenyls (PCBs) and hexachlorobenzene (HCB) was investigated along a spatial gradient in water, sediments and in commercially important bivalve species Scrobicularia plana, from Ria de Aveiro (Portugal). Organochlorines dissolved in water were below detection limit and concerning suspended particulate matter, only PCBs were quantified, ranging from 3.8 to 5.8 ng∙g(-1) DW (Σ13PCBs). There was a distinct spatial gradient regarding PCB accumulation in sediments. The highest concentrations were found in deeper layers and closest to the pollution source, decreasing gradually along a 3 km area. Contamination in sediments exceeded the Canadian and Norwegian sediment quality guidelines, inducing potential toxic effects in related biota. PCBs tended to bioaccumulate throughout S. plana lifespan but with different annual rates along the spatial gradient. The maximum values were found in older individuals up to 3+ years old, reaching 19.4 ng∙g(-1) DW. HCB concentrations were residual and no bioaccumulation pattern was evident. Congeners 138, 153 and 180 were the most accumulated due to their abundance and long-term persistence in the environment. In the inner area of the Laranjo Bay (0.6 km(2)), the species was able to remove up to 0.4 g of PCBs annually from sediments into their own tissues, which is consequently free for trophic transfer (biomagnification). Concerning human health, and despite the high concentrations found in sediments, PCB levels in bivalves do not exceed the limit established by the European Union for fishery products and are largely below tolerable daily intake. Although PCBs in Scrobicularia plana are present at low levels, their impact to human health after consumption over many years might be harmful and should be monitored in future studies.

  10. Evidence for gas accumulation associated with diapirism and gas hydrates at the head of the Cape Fear Slide

    USGS Publications Warehouse

    Schmuck, E.A.; Paull, C.K.

    1993-01-01

    Single-channel seismic reflection profiles show evidence for areas of significant gas accumulation at the head of the Cape Fear Slide on the continental rise off North Carolina. Gas accumulation appears to occur beneath a gas hydrate seal in landward-dipping strata and in domed strata associated with diapirism. In addition, gas venting may have occurred near diapirs located at the head of the slide. ?? 1993 Springer-Verlag.

  11. E-cadherin inhibits nuclear accumulation of Nrf2: implications for chemoresistance of cancer cells.

    PubMed

    Kim, Won Dong; Kim, Young Woo; Cho, Il Je; Lee, Chang Ho; Kim, Sang Geon

    2012-03-01

    Nrf2 has an anti-carcinogenic effect. However, an increase in Nrf2 activity is also implicated in cancer chemoresistance. A switch from E-cadherin to N-cadherin affects the transdifferentiation and metastasis of cancer cells. In view of the key role of this switch in cancer malignancy, we investigated the regulatory effect of E-cadherin on Nrf2. In HEK293 cells, overexpression of E-cadherin inhibited the nuclear accumulation of Nrf2, and prevented Nrf2-dependent gene induction. GST pull-down and immunocytochemical assays verified the interaction between E-cadherin and Nrf2: E-cadherin bound the C-terminus of Nrf2, but not its N-terminus, which comprises the Neh2 domain responsible for phosphorylation of Ser40. Our finding that the mutation of Ser40 to alanine in Nrf2 did not affect the ability of E-cadherin to bind Nrf2 and repress target gene transactivation suggests that E-cadherin might not disturb the phosphorylation. Studies using mutant constructs of E-cadherin suggested that the β-catenin-binding domain contributes to the inhibitory effect of E-cadherin on Nrf2. Consistently, knockdown of β-catenin attenuated not only the effect of E-cadherin binding to Nrf2, but also Keap1-dependent ubiquitylation of Nrf2, and thereby increased Nrf2 activity, supporting the involvement of β-catenin in the interactions. Collectively, E-cadherin recruits Nrf2 through β-catenin, and assists the function of Keap1 for the inhibition of nuclear localization and transcriptional activity of Nrf2. In HepG2 cells, the loss of E-cadherin by either siRNA knockdown or treatment with TGFβ1 enhanced the constitutive or inducible activity of Nrf2, implying that chemoresistance of cancer cells upon the loss of E-cadherin might be associated with Nrf2. PMID:22302998

  12. Implications of neuropsychological evidence for theories of normal memory.

    PubMed

    Baddeley, A D

    1982-06-25

    The relation between neuropsychology and the study of normal cognitive function is discussed in the context of recent research on human memory. It is suggested that neuropsychological evidence has clear implications for the fractionation of human memory into subsystems. The distinction between long-term and short-term memory, between semantic and episodic memory, and the further fractionation of short-term or working memory all offer examples of concepts that have been successfully applied within the neuropsychological domain, and where the neuropsychological evidence has led to a modification and development of the original concept. Attempts to offer a cognitive interpretation of the amnesic syndrome are discussed. While none of these is entirely satisfactory, such work has led to a potentially important distinction between autobiographical memory or recollection, which is defective in amnesic patients, and a more perceptual or procedural learning process, which appears to be intact in such patients. Recent research on normal subjects is beginning to reveal a similar distinction. It is concluded that the relation between neuropsychology and the study of normal cognitive function continues to be an extremely fruitful one.

  13. Precision and neuronal dynamics in the human posterior parietal cortex during evidence accumulation

    PubMed Central

    FitzGerald, Thomas H.B.; Moran, Rosalyn J.; Friston, Karl J.; Dolan, Raymond J.

    2015-01-01

    Primate studies show slow ramping activity in posterior parietal cortex (PPC) neurons during perceptual decision-making. These findings have inspired a rich theoretical literature to account for this activity. These accounts are largely unrelated to Bayesian theories of perception and predictive coding, a related formulation of perceptual inference in the cortical hierarchy. Here, we tested a key prediction of such hierarchical inference, namely that the estimated precision (reliability) of information ascending the cortical hierarchy plays a key role in determining both the speed of decision-making and the rate of increase of PPC activity. Using dynamic causal modelling of magnetoencephalographic (MEG) evoked responses, recorded during a simple perceptual decision-making task, we recover ramping-activity from an anatomically and functionally plausible network of regions, including early visual cortex, the middle temporal area (MT) and PPC. Precision, as reflected by the gain on pyramidal cell activity, was strongly correlated with both the speed of decision making and the slope of PPC ramping activity. Our findings indicate that the dynamics of neuronal activity in the human PPC during perceptual decision-making recapitulate those observed in the macaque, and in so doing we link observations from primate electrophysiology and human choice behaviour. Moreover, the synaptic gain control modulating these dynamics is consistent with predictive coding formulations of evidence accumulation. PMID:25512038

  14. Silica uptake by Spartina—evidence of multiple modes of accumulation from salt marshes around the world

    PubMed Central

    Carey, Joanna C.; Fulweiler, Robinson W.

    2014-01-01

    Silicon (Si) plays a critical role in plant functional ecology, protecting plants from multiple environmental stressors. While all terrestrial plants contain some Si, wetland grasses are frequently found to have the highest concentrations, although the mechanisms driving Si accumulation in wetland grasses remain in large part uncertain. For example, active Si accumulation is often assumed to be responsible for elevated Si concentrations found in wetland grasses. However, life stage and differences in Si availability in the surrounding environment also appear to be important variables controlling the Si concentrations of wetland grasses. Here we used original data from five North American salt marshes, as well as all known published literature values, to examine the primary drivers of Si accumulation in Spartina, a genus of prolific salt marsh grasses found worldwide. We found evidence of multiple modes of Si accumulation in Spartina, with passive accumulation observed in non-degraded marshes where Spartina was native, while rejective accumulation was found in regions where Spartina was invasive. Evidence of active accumulation was found in only one marsh where Spartina was native, but was also subjected to nutrient over-enrichment. We developed a conceptual model which hypothesizes that the mode of Si uptake by Spartina is dependent on local environmental factors and genetic origin, supporting the idea that plant species should be placed along a spectrum of Si accumulation. We hypothesize that Spartina exhibits previously unrecognized phenotypic plasticity with regard to Si accumulation, allowing these plants to respond to changes in marsh condition. These results provide new insight regarding how salt marsh ecosystems regulate Si exchange at the land-sea interface. PMID:24904599

  15. Variation in copper and zinc tolerance and accumulation in 12 willow clones: implications for phytoextraction*

    PubMed Central

    Yang, Wei-dong; Wang, Yu-yan; Zhao, Feng-liang; Ding, Zhe-li; Zhang, Xin-cheng; Zhu, Zhi-qiang; Yang, Xiao-e

    2014-01-01

    Willows (Salix spp.) have shown high potential for the phytoextraction of heavy metals. This study compares variations in copper (Cu) and zinc (Zn) tolerance and accumulation potential among 12 willow clones grown in a nutrient solution treated with 50 μmol/L of Cu or Zn, respectively. The results showed differences in the tolerance and accumulation of Cu and Zn with respect to different species/clones. The biomass variation among clones in response to Cu or Zn exposure ranged from the stimulation of growth to inhibition, and all of the clones tested showed higher tolerance to Cu than to Zn. The clones exhibited less variation in Cu accumulation but larger variation in Zn accumulation. Based on translocation factors, it was found that most of the Cu was retained in the roots and that Zn was more mobile than Cu for all clones. It is concluded that most willow clones are good accumulators of Zn and Cu. PMID:25183033

  16. Variation in copper and zinc tolerance and accumulation in 12 willow clones: implications for phytoextraction.

    PubMed

    Yang, Wei-dong; Wang, Yu-yan; Zhao, Feng-liang; Ding, Zhe-li; Zhang, Xin-cheng; Zhu, Zhi-qiang; Yang, Xiao-e

    2014-09-01

    Willows (Salix spp.) have shown high potential for the phytoextraction of heavy metals. This study compares variations in copper (Cu) and zinc (Zn) tolerance and accumulation potential among 12 willow clones grown in a nutrient solution treated with 50 μmol/L of Cu or Zn, respectively. The results showed differences in the tolerance and accumulation of Cu and Zn with respect to different species/clones. The biomass variation among clones in response to Cu or Zn exposure ranged from the stimulation of growth to inhibition, and all of the clones tested showed higher tolerance to Cu than to Zn. The clones exhibited less variation in Cu accumulation but larger variation in Zn accumulation. Based on translocation factors, it was found that most of the Cu was retained in the roots and that Zn was more mobile than Cu for all clones. It is concluded that most willow clones are good accumulators of Zn and Cu. PMID:25183033

  17. Social capital: theory, evidence, and implications for oral health.

    PubMed

    Rouxel, Patrick L; Heilmann, Anja; Aida, Jun; Tsakos, Georgios; Watt, Richard G

    2015-04-01

    In the last two decades, there has been increasing application of the concept of social capital in various fields of public health, including oral health. However, social capital is a contested concept with debates on its definition, measurement, and application. This study provides an overview of the concept of social capital, highlights the various pathways linking social capital to health, and discusses the potential implication of this concept for health policy. An extensive and diverse international literature has examined the relationship between social capital and a range of general health outcomes across the life course. A more limited but expanding literature has also demonstrated the potential influence of social capital on oral health. Much of the evidence in relation to oral health is limited by methodological shortcomings mainly related to the measurement of social capital, cross-sectional study designs, and inadequate controls for confounding factors. Further research using stronger methodological designs should explore the role of social capital in oral health and assess its potential application in the development of oral health improvement interventions.

  18. Ice core evidence for a recent increase in snow accumulation in coastal Dronning Maud Land, Antarctica

    NASA Astrophysics Data System (ADS)

    Philippe, Morgane; Tison, Jean-Louis; Fjøsne, Karen; Hubbard, Bryn; Kjær, Helle Astrid; Lenaerts, Jan; Sheldon, Simon Geoffrey; De Bondt, Kevin; Claeys, Philippe; Pattyn, Frank

    2016-04-01

    Ice cores provide temporal records of snow accumulation, a crucial component of Antarctic mass balance. Coastal areas are particularly under-represented in such records, despite their relatively high and sensitive accumulation rates. Here we present records from a 120 m ice core drilled on Derwael Ice Rise, coastal Dronning Maud Land (DML), East Antarctica in 2012. We date the ice core bottom back to 1745 ± 2 AD. δ18O and δD stratigraphy is supplemented by discontinuous major ion profiles, and verified independently by electrical conductivity measurements (ECM) to detect volcanic horizons. The resulting annual layer history is combined with the core density profile to calculate accumulation history, corrected for the influence of ice deformation. The mean long-term accumulation is 0.425 ± 0.035 m water equivalent (w.e.) a-1 (average corrected value). Reconstructed annual accumulation rates show an increase from 1955 onward to a mean value of 0.61 ± 0.02 m w.e. a-1 between 1955 and 2012. This trend is compared to other reported accumulation data in Antarctica, generally showing a high spatial variability. Applying the Community Earth System Model demonstrated that sea ice and atmosphere patterns largely explain the accumulation variability. This is the first and longest record from a coastal ice core in East Antarctica showing a steady increase during the 20th and 21st centuries, thereby confirming modelling predictions.

  19. Experimental models of microcystin accumulation in Daphnia magna grazing on Planktothrix rubescens: implications for water management.

    PubMed

    Shams, Shiva; Cerasino, Leonardo; Salmaso, Nico; Dietrich, Daniel R

    2014-03-01

    In this study, we investigated the kinetic aspects of the microcystin (MC) transfer from Planktothrix rubescens to Daphnia magna by carrying out exposure experiments in small simple mesocosms. We hypothesized that higher fractions of toxic cyanobacteria in the diet of grazers would shift the balance towards a greater than linear, i.e. non-linear accumulation of MC in D. magna. This hypothesis was tested by exposing D. magna to varying initial densities of MC-producing P. rubescens. The evolving models of MC accumulation differed largely as a result of the duration of exposure and initial MC concentrations used. Within the first 24h of exposure, MC accumulation in D. magna was linear, irrespective of the initial densities of toxic P. rubescens and thus MC concentrations. After 48 h of exposure, MC accumulation in D. magna showed an exponential pattern, possibly due to a delayed digestion of P. rubescens and/or decreased MC detoxification capabilities when compared with higher ambient concentrations of MC. After 72 h toxin concentrations in Daphnia drop in all experiments as a consequence of the reduced cyanobacterial cells in the medium and the detoxification of MC within Daphnia. The results obtained suggest that in lakes with higher MC content and longer cyanobacterial bloom period MC accumulation in D. magna should be more pronounced than in mesotrophic lakes with lower MC content. The latter interpretation, however, should be verified investigating accumulation of MC both in larger mesocosms and in situ, in lakes of different trophic status.

  20. Carbon accumulation in Bay of Fundy salt marshes: Implications for restoration of reclaimed marshes

    NASA Astrophysics Data System (ADS)

    Connor, Richard F.; Chmura, Gail L.; Beecher, C. Beth

    2001-12-01

    Transformation of agricultural land to natural terrestrial vegetation has been suggested as a means to increase soil carbon storage. However, the capacity for carbon storage in terrestrial soils is limited as compared to soils of tidal salt marshes, the original vegetation of many coastal agricultural lands. In a number of countries, tidal salt marshes have been "reclaimed," that is drained and diked to prevent tidal flooding and create suitable conditions for dry land agriculture. In this study we examine spatial and temporal patterns of carbon accumulation in tidal salt marshes of the Bay of Fundy and estimate the carbon storage potential of the bay's extensive area of reclaimed marsh. Rates of carbon accumulation vary from the upper to the outer Bay, over which there is a gradient of decreasing tidal range and suspended sediment supply. In the outer bay, high-marsh densities are highest (0.042 ± 0.009 g C cm-3), but carbon accumulation rates over the past 30 years are lowest (76 g C m-2 yr-1). The reverse pattern occurs in the upper bay where carbon densities in the high-marsh environment are lowest (0.036 ± 0.002 g C cm-3), but carbon accumulation rates over the past 30 years may be as high (184 g C m-2 yr-1). Compared to other ecosystems, the rates of carbon accumulation presented in this study were similar over timescales of years to centuries. Increases in relative sea level (over time) and suspended sediment supply (across the bay) positively affect the marsh soil accumulation rate and the rate of carbon sequestration. Parameters such as %C are not useful predictors of a marsh's potential for carbon sequestration. Soil carbon densities of functioning marshes and reclaimed marsh soils are similar, but marsh soils have a storage capacity that increases with rising sea level, while agricultural soils, such as those in reclaimed marshes, have a fixed (or possibly decreasing in reclaimed marshes) volume over time.

  1. Experimental evidence for the accumulation of egg pigment in the brain cavities of Xenopus tadpoles.

    PubMed

    Kordylewski, L

    1983-07-01

    The origin and fate of darkly pigmented clusters of cells that float freely in the brain cavities of the tadpoles of Xenopus laevis have been experimentally investigated. The results point to the conclusion that the clusters are the sites of egg pigment accumulation, which remain within the brain cavities or at its walls until metamorphosis.

  2. Cd and Ni transport and accumulation in the halophyte Sesuvium portulacastrum: implication of organic acids in these processes

    PubMed Central

    Mnasri, Mejda; Ghabriche, Rim; Fourati, Emna; Zaier, Hanen; Sabally, Kebba; Barrington, Suzelle; Lutts, Stanley; Abdelly, Chedly; Ghnaya, Tahar

    2015-01-01

    The implication of organic acids in Cd and Ni translocation was studied in the halophyte species Sesuvium portulacastrum. Citric, fumaric, malic, and ascorbic acids were separated and quantified by HPLC technique in shoots, roots and xylem saps of plants grown on nutrient solutions added with 50 μM Cd, 100 μM Ni and the combination of 50 μM Cd + 100 μM Ni. Results showed that Cd had no significant impact on biomass production while Ni and the combination of both metals drastically affected plant development. Cadmium and Ni concentrations in tissues and xylem sap were higher in plants subjected to individual metal application than those subjected to the combined effect of Cd and Ni suggesting a possible competition between these metals for absorption. Both metals applied separately or in combination induced an increase in citrate concentration in shoots and xylem sap but a decrease of this concentration in the roots. However, a minor relationship was observed between metal application and fumaric, malic, and ascorbic acids. Both observations suggest the implication of citric acid in Cd, Ni translocation and shoot accumulation in S. portulacastrum. The relatively high accumulation of citric acid in xylem sap and shoot of S. portulacastrum could be involved in metal chelation and thus contributes to heavy metal tolerance in this species. PMID:25821455

  3. Trends and drivers of debris accumulation on Maui shorelines: Implications for local mitigation strategies.

    PubMed

    Blickley, Lauren C; Currie, Jens J; Kaufman, Gregory D

    2016-04-15

    Marine debris, particularly plastic, is an identified concern for coastal areas and is known to accumulate in large quantities in the North Pacific. Here we present results from the first study to quantify and compare the types and amounts of marine debris on Maui shorelines. Surveys were conducted monthly between May 2013 and December 2014, with additional daily surveys conducted on Maui's north shore during January 2015. Debris accumulation rates, loads, and sources varied between sites, with plastics being the most prevalent type of debris at all sites. Large debris loads on windward shores were attributed to the influence of the North Pacific Subtropical Gyre and northerly trade winds. Daily surveys resulted in a significantly higher rate of debris deposition than monthly surveys. The efficacy of local policy in debris mitigation showed promise, but was dependent upon the level of enforcement and consumer responsibility. PMID:26926778

  4. Trends and drivers of debris accumulation on Maui shorelines: Implications for local mitigation strategies.

    PubMed

    Blickley, Lauren C; Currie, Jens J; Kaufman, Gregory D

    2016-04-15

    Marine debris, particularly plastic, is an identified concern for coastal areas and is known to accumulate in large quantities in the North Pacific. Here we present results from the first study to quantify and compare the types and amounts of marine debris on Maui shorelines. Surveys were conducted monthly between May 2013 and December 2014, with additional daily surveys conducted on Maui's north shore during January 2015. Debris accumulation rates, loads, and sources varied between sites, with plastics being the most prevalent type of debris at all sites. Large debris loads on windward shores were attributed to the influence of the North Pacific Subtropical Gyre and northerly trade winds. Daily surveys resulted in a significantly higher rate of debris deposition than monthly surveys. The efficacy of local policy in debris mitigation showed promise, but was dependent upon the level of enforcement and consumer responsibility.

  5. The Mediterranean non-indigenous ascidian Polyandrocarpa zorritensis: Microbiological accumulation capability and environmental implications.

    PubMed

    Stabili, Loredana; Licciano, Margherita; Longo, Caterina; Lezzi, Marco; Giangrande, Adriana

    2015-12-15

    We investigated the bacterial accumulation and digestion capability of Polyandrocarpa zorritensis, a non-indigenous colonial ascidian originally described in Peru and later found in the Mediterranean. Microbiological analyses were carried out on homogenates from "unstarved" and "starved" ascidians and seawater from the same sampling site (Adriatic Sea, Italy). Culturable heterotrophic bacteria (22 °C), total culturable bacteria (37 °C) and vibrios abundances were determined on Marine Agar 2216, Plate Count Agar and TCBS Agar, respectively. Microbial pollution indicators were measured by the most probable number method. All the examined microbiological groups were accumulated by ascidians but differently digested. An interesting outcome is the capability of P. zorritensis to digest allochthonous microorganisms such as coliforms as well as culturable bacteria at 37 °C, counteracting the effects of microbial pollution. Thus, the potential exploitation of these filter feeders to restore polluted seawater should be taken into consideration in the management of this alien species. PMID:26561443

  6. GCM Simulations of Tropical Ice Accumulations: Implications for Cold-based Glaciers

    NASA Technical Reports Server (NTRS)

    Haberle, R. M.; Montmessin, F.; Forget, F.; Levrard, B.; Head, J. W., III; Laskar, J.

    2004-01-01

    Each of the three Tharsis Montes shield volcanoes on Mars has fan-shaped deposits on their flanks. A detailed analysis of the multiple facies of the Arsia Mons deposits, coupled with field observations of polar glaciers in Antarctica, shows that they are consistent with deposition from cold-based mountain glaciers. Key features of these glaciers are: (1) they formed only on the western flank of each volcano, (2) enough ice accumulated to cause them to flow but without basal melting, (3) there were multiple advances and retreats, (4) the last major glaciation was more than several million years ago, (5) the areal extent of the deposits they left behind decreases northward, (6) together the deposits range in elevation from a low of 1.5 to a high of 8.5 km, and (7) there are no signs that significant accumulation is occurring today.

  7. Crustal strain accumulation on Southern Basin and Range Province faults modulated by distant plate boundary earthquakes? Evidence from geodesy, seismic imaging, and paleoseismology

    NASA Astrophysics Data System (ADS)

    Bennett, R. A.; Shirzaei, M.; Broermann, J.; Spinler, J. C.; Holland, A. A.; Pearthree, P.

    2014-12-01

    GPS in Arizona reveals a change in the pattern of crustal strain accumulation in 2010 and based on viscoelastic modeling appears to be associated with the distant M7.2 El Mayor-Cucapah (EMC) earthquake in Baja California, Mexico. GPS data collected between 1999 and 2009 near the Santa Rita normal fault in SE Arizona reveal a narrow zone of crustal deformation coincident with the fault trace, delineated by W-NW facing Pleistocene fault scarps of heights 1 to 7 m. The apparent deformation zone is also seen in a preliminary InSAR interferogram. Total motion across the zone inferred using an elastic block model constrained by the pre-2010 GPS measurements is ~1 mm/yr in a sense consistent with normal fault motion. However, continuous GPS measurements throughout Arizona reveal pronounced changes in crustal velocity following the EMC earthquake, such that the relative motion across the Santa Rita fault post-2010 is negligible. Paleoseismic evidence indicates that mapped Santa Rita fault scarps were formed by two or more large magnitude (M6.7 to M7.6) surface rupturing normal-faulting earthquakes 60 to 100 kyrs ago. Seismic refraction and reflection data constrained by deep (~800 m) well log data provide evidence of progressive, possibly intermittent, displacement on the fault through time. The rate of strain accumulation observed geodetically prior to 2010, if constant over the past 60 to 100 kyrs, would imply an untenable minimum slip rate deficit of 60 to 100 m since the most recent earthquake. One explanation for the available geodetic, seismic, and paleoseismic evidence is that strain accumulation is modulated by viscoelastic relaxation associated with frequent large magnitude earthquakes in the Salton Trough region, episodically inhibiting the accumulation of elastic strain required to generate large earthquakes on the Santa Rita and possibly other faults in the Southern Basin and Range. An important question is thus for how long the postseismic velocity changes

  8. Carbon accumulation rate of peatland in the High Arctic, Svalbard: Implications for carbon sequestration

    NASA Astrophysics Data System (ADS)

    Nakatsubo, Takayuki; Uchida, Masaki; Sasaki, Akiko; Kondo, Miyuki; Yoshitake, Shinpei; Kanda, Hiroshi

    2015-06-01

    Moss tundra that accumulates a thick peat layer is one of the most important ecosystems in the High Arctic, Svalbard. The importance of this ecosystem for carbon sequestration was estimated from the apparent rates of carbon accumulation based on the 14C age and amount of peat in the active layer. The study site at Stuphallet, Brøgger Peninsula, northwestern Svalbard was covered with a thick peat layer dominated by moss species such as Calliergon richardsonii, Paludella squarrosa, Tomenthypnum nitens, and Warnstorfia exannulata. The average thickness of the active layer (brown moss and peat) was approximately 28 cm in 1 August 2011. The calibrated (cal) age of peat from the bottom of the active layer (20-30 cm below the peatland surface) ranged from 81 to 701 cal yr BP (median value of 2σ range). Based on the total carbon (4.5-9.2 kg C m-2), the apparent rate of carbon accumulation in the active layer was 9.0-19.2 (g C m-2 yr-1), which is similar to or greater than the net ecosystem production or net primary production reported for other vegetation types in this area. Our data suggest that moss tundra plays an important role in carbon sequestration in this area.

  9. Meteorite infall as a function of mass - Implications for the accumulation of meteorites on Antarctic ice

    NASA Technical Reports Server (NTRS)

    Huss, Gary R.

    1990-01-01

    Antarctic meteorites are considerably smaller, on average, than those recovered elsewhere in the world, and seem to represent a different portion of the mass distribution of infalling meteorites. When an infall rate appropriate to the size of Antarctic meteorites is used (1000 meteorites 10 grams or larger/sq km/1 million years), it is found that direct infall can produce the meteorite accumulations found on eight ice fields in the Allan Hills region in times ranging from a few thousand to nearly 200,000 years, with all but the Allan Hills Main and Near Western ice fields requiring less than 30,000 years. Meteorites incorporated into the ice over time are concentrated on the surface when the ice flows into a local area of rapid ablation. The calculated accumulation times, which can be considered the average age of the exposed ice, agree well with terrestrial ages for the meteorites and measured ages of exposed ice. Since vertical concentration of meteorites through removal of ice by ablation is sufficient to explain the observed meteorite accumulations, there is no need to invoke mechanisms to bring meteorites from large areas to the relatively small blue-ice patches where they are found. Once a meteorite is on a bare ice surface, freeze-thaw cycling and wind break down the meteorite and remove it from the ice. The weathering lifetime of a 100-gram meteorite on Antarctic ice is on the order of 10,000 + or - 5,000 years.

  10. Catastrophic ecosystem shifts in dry tropical forest: evidence, mechanisms and implications for climate change

    NASA Astrophysics Data System (ADS)

    Lawrence, D.; D'Odorico, P.; Runyan, C.; Diekmann, L.; DeLonge, M. S.; Das, R.; Eaton, J.; Vandecar, K.; Schmook, B.

    2015-12-01

    Tropical dry forests have long been used by humans. Has it been sustainable? Not in the southern Yucatan. Biomass accumulation declines with each cycle of shifting cultivation with implications for both internal recycling of nutrients and external inputs of nutrients. We detail the evidence for a decline in P inputs from biomass burning (aboveground biomass, litter, and coarse woody debris), an increase in leaching losses from deep soils, and a decline in atmospheric inputs of new P from Saharan dust following the transition from mature to secondary forest. Canopy trapping of dust is critical to maintaining P balance in this system. Effective trapping is diminished by changes in the structure of secondary forest--loss of height, leaf area and basal area. Experimental studies show that it is atmospheric transport of dust, not microbial shedding or leaching from live tissues, that explains the difference between throughfall P and P in bulk deposition. Because of net losses in P, uptake of carbon during regrowth is slower with each cycle of shifting cultivation. As much of the tropics has moved beyond a mature forest frontier, the decline in carbon sequestration is likely widespread over both dry and wet forests. The terrestrial carbon sink in the tropics may be declining. The capacity to sequester carbon through afforestation, reforestation and restoration has certainly diminished over time, limiting the effectiveness of such efforts to help mitigate climate change.

  11. Analysis of storage lipid accumulation in Alcanivorax borkumensis: Evidence for alternative triacylglycerol biosynthesis routes in bacteria.

    PubMed

    Kalscheuer, Rainer; Stöveken, Tim; Malkus, Ursula; Reichelt, Rudolf; Golyshin, Peter N; Sabirova, Julia S; Ferrer, Manuel; Timmis, Kenneth N; Steinbüchel, Alexander

    2007-02-01

    Marine hydrocarbonoclastic bacteria, like Alcanivorax borkumensis, play a globally important role in bioremediation of petroleum oil contamination in marine ecosystems. Accumulation of storage lipids, serving as endogenous carbon and energy sources during starvation periods, might be a potential adaptation mechanism for coping with nutrient limitation, which is a frequent stress factor challenging those bacteria in their natural marine habitats. Here we report on the analysis of storage lipid biosynthesis in A. borkumensis strain SK2. Triacylglycerols (TAGs) and wax esters (WEs), but not poly(hydroxyalkanoic acids), are the principal storage lipids present in this and other hydrocarbonoclastic bacterial species. Although so far assumed to be a characteristic restricted to gram-positive actinomycetes, substantial accumulation of TAGs corresponding to a fatty acid content of more than 23% of the cellular dry weight is the first characteristic of large-scale de novo TAG biosynthesis in a gram-negative bacterium. The acyltransferase AtfA1 (ABO_2742) exhibiting wax ester synthase/acyl-coenzyme A:diacylglycerol acyltransferase (WS/DGAT) activity plays a key role in both TAG and WE biosynthesis, whereas AtfA2 (ABO_1804) was dispensable for storage lipid formation. However, reduced but still substantial residual TAG levels in atfA1 and atfA2 knockout mutants compellingly indicate the existence of a yet unknown WS/DGAT-independent alternative TAG biosynthesis route. Storage lipids of A. borkumensis were enriched in saturated fatty acids and accumulated as insoluble intracytoplasmic inclusions exhibiting great structural variety. Storage lipid accumulation provided only a slight growth advantage during short-term starvation periods but was not required for maintaining viability and long-term persistence during extended starvation phases. PMID:17122340

  12. Characteristics of nonylphenol and bisphenol A accumulation by fish and implications for ecological and human health.

    PubMed

    Lee, Ching-Chang; Jiang, Ling-Ying; Kuo, Yi-Ling; Chen, Chung-Yu; Hsieh, Chia-Yi; Hung, Chung-Feng; Tien, Chien-Jung

    2015-01-01

    Fish populations constitute an important part of aquatic ecosystems. Thus, their accumulation of nonylphenol (NP) and bisphenol A (BPA) may pose risks to ecosystems and human health. This study analyzed the concentrations of NP and BPA in four types of fishes (i.e., wild/farmed freshwater fishes and wild/farmed marine fishes). Wild freshwater fishes contained higher concentrations of NP and BPA than the other three types of fishes. The concentrations of NP in the wild freshwater fishes ranged from 1.01 to 277 μg/kg ww, with bioconcentration factors (BCFs) and biota-sediment accumulation factors (BSAFs) ranging from 74.0 to 2.60 × 10(4)L/kg and from 0.003 to 18.3, respectively. The wild freshwater fishes contained relatively low amounts of BPA, varying from ND to 25.2 μg/kg ww, with the BCFs and BSAFs ranging from 1.00 to 274L/kg and from 0.003 to 3.40, respectively. Five fish species particularly showed high BCFs and BSAFs, indicating that they could be an important source of NP for higher trophic levels, most likely resulting in ecological risks. The demersal fishes showed a greater ability to accumulate NP than the pelagic ones. The fact that the 95th percentile values of the risk quotient (RQ) for NP and BPA were higher than the acceptable threshold indicated that these two compounds would have adverse effects on aquatic organisms in Taiwanese rivers. The consumption of wild marine fishes had the highest 95th percentile values of hazard quotient (HQ) for NP and BPA among the four types of fishes, particularly for the population aged 0-3 years. However, the 95th percentile values of HQ for NP and BPA were all less than 1, suggesting that exposure to NP and BPA through fish consumption posed no remarkable risk to human health in Taiwan.

  13. Modeling magmatic accumulations in the upper crust: Metamorphic implications for the country rock

    NASA Astrophysics Data System (ADS)

    Douglas, Madison M.; Geyer, Adelina; Álvarez-Valero, Antonio M.; Martí, Joan

    2016-06-01

    Field exposures of magma chambers tend to reveal contact metamorphic aureoles in the surrounding crust, which width varies from few centimeters to kilometers. The igneous accumulation not only increases the temperature around it, but also weakens its surrounding country rock beyond the brittle-ductile transition temperature. The formation of a ductile halo around the magmatic reservoir may significantly impact into the stability and growth of the magma chamber, as well as into potential dyke injections and processes of ground deformation. In this paper, we examine how a magmatic accumulation affects the country rock through the combination of petrologic and thermal perspectives. For this, we numerically modeled (i) the conductive cooling of an instantaneously emplaced magma chamber within compositionally representative pelitic and carbonate upper crusts, and (ii) the corresponding changes in the viscosity of the host rock potentially leading to ductile regimes. We consider basaltic to rhyolitic magma chambers at different depths with oblate, prolate and spherical geometries. The resulting temperature field distribution at different time steps is integrated with crustal metamorphic effects through phase diagram modeling. Our results indicate that the geometry of the magma accumulations plays a dominant role in controlling the local metamorphic and thermal effects on the country rocks. They conclude that (i) the combination of relatively simple geothermal models with petrologic datasets can generate first order predictions for the maximum metamorphic grade and geometry of magma chamber aureoles; (ii) the possible changes in the mechanical properties of the country rock are not necessarily linked to the petrological changes in contact aureoles; and (iii) the present rheologic outcomes may be used in further studies of magma chamber stability and integrity, which may favor the understanding of the melt transfer throughout the crust.

  14. HMGB1 and RAGE in skeletal muscle inflammation: Implications for protein accumulation in inclusion body myositis.

    PubMed

    Muth, Ingrid E; Zschüntzsch, Jana; Kleinschnitz, Konstanze; Wrede, Arne; Gerhardt, Ellen; Balcarek, Peter; Schreiber-Katz, Olivia; Zierz, Stephan; Dalakas, Marinos C; Voll, Reinhard E; Schmidt, Jens

    2015-09-01

    Inflammation is associated with protein accumulation in IBM, but precise mechanisms are elusive. The "alarmin" HMGB1 is upregulated in muscle inflammation. Its receptor RAGE is crucial for β-amyloid-associated neurodegeneration. Relevant signaling via HMGB1/RAGE is expected in IBM pathology. By real-time-PCR, mRNA-expression levels of HMGB1 and RAGE were upregulated in muscle biopsies of patients with IBM and PM, but not in muscular dystrophy or non-myopathic controls. By immunohistochemistry, both molecules displayed the highest signal in IBM, where they distinctly co-localized to intra-fiber accumulations of β-amyloid and neurofilament/tau. In these fibers, identification of phosphorylated Erk suggested that relevant downstream activation is present upon HMGB1 signaling via RAGE. Protein expressions of HMGB1, RAGE, Erk and phosphorylated Erk were confirmed by Western blot. In a well established cell-culture model for pro-inflammatory cell-stress, exposure of human muscle-cells to IL-1β+IFN-γ induced cytoplasmic translocation of HMGB1 and subsequent release as evidenced by ELISA. Upregulation of RAGE on the cell surface was demonstrated by immunocytochemistry and flow-cytometry. Recombinant HMGB1 was equally potent as IL-1β+IFN-γ in causing amyloid-accumulation and cell-death, and both were abrogated by the HMGB1-blocker BoxA. The findings strengthen the concept of unique interactions between degenerative and inflammatory mechanisms and suggest that HMGB1/RAGE signaling is a critical pathway in IBM pathology.

  15. Accumulation of mercury by aufwuchs in Wisconsin seepage lakes: Implications for monitoring

    USGS Publications Warehouse

    Cope, W. Gregory; Rada, Ronald G.

    1992-01-01

    We examined temporal variation in the total Hg content of aufwuchs (attached algae) collected from artificial substrates in 11 seepage lakes in north-central Wisconsin and its relation to the Hg content of resident yellow perch Perca flavescens from the lakes. Dry weight concentrations of Hg in aufwuchs varied temporally, as follows: summer/fall 1985 > summer 1985 > spring/summer 1986. Areal concentrations of Hg during the 1985 sampling periods were greater than concentrations during the spring/summer 1986 period, but did not differ from each other. The analyses of aufwuchs do not indicate potential accumulation of Hg in fish in these lakes.

  16. Focus Group Evidence: Implications for Design and Analysis

    ERIC Educational Resources Information Center

    Ryan, Katherine E.; Gandha, Tysza; Culbertson, Michael J.; Carlson, Crystal

    2014-01-01

    In evaluation and applied social research, focus groups may be used to gather different kinds of evidence (e.g., opinion, tacit knowledge). In this article, we argue that making focus group design choices explicitly in relation to the type of evidence required would enhance the empirical value and rigor associated with focus group utilization. We…

  17. Toxic Takifugu pardalis eggs found in Takifugu niphobles gut: Implications for TTX accumulation in the pufferfish.

    PubMed

    Itoi, Shiro; Kozaki, Ao; Komori, Keitaro; Tsunashima, Tadasuke; Noguchi, Shunsuke; Kawane, Mitsuo; Sugita, Haruo

    2015-12-15

    Pufferfish (Takifugu spp.) possess a potent neurotoxin, tetrodotoxin (TTX). TTX has been detected in various organisms including food animals of pufferfish, and TTX-producing bacteria have been isolated from these animals. TTX in marine pufferfish accumulates in the pufferfish via the food web starting with marine bacteria. However, such accumulation is unlikely to account for the amount of TTX in the pufferfish body because of the minute amounts of TTX produced by marine bacteria. Therefore, the toxification process in pufferfish still remains unclear. In this article we report the presence of numerous Takifugu pardalis eggs in the intestinal contents of another pufferfish, Takifugu niphobles. The identity of T. pardalis being determined by direct sequencing for mitochondrial DNA. LC-MS/MS analysis revealed that the peak detected in the egg samples corresponded to TTX. Toxification experiments in recirculating aquaria demonstrated that cultured Takifugu rubripes quickly became toxic upon being fed toxic (TTX-containing) T. rubripes eggs. These results suggest that T. niphobles ingested the toxic eggs of another pufferfish T. pardalis to toxify themselves more efficiently via a TTX loop consisting of TTX-bearing organisms at a higher trophic level in the food web.

  18. Lions as Bone Accumulators? Paleontological and Ecological Implications of a Modern Bone Assemblage from Olduvai Gorge

    PubMed Central

    Arriaza, Mari Carmen; Domínguez-Rodrigo, Manuel; Yravedra, José; Baquedano, Enrique

    2016-01-01

    Analytic models have been developed to reconstruct early hominin behaviour, especially their subsistence patterns, revealed mainly through taphonomic analyses of archaeofaunal assemblages. Taphonomic research is used to discern which agents (carnivores, humans or both) generate the bone assemblages recovered at archaeological sites. Taphonomic frameworks developed during the last decades show that the only large-sized carnivores in African biomes able to create bone assemblages are leopards and hyenas. A carnivore-made bone assemblage located in the short-grassland ecological unit of the Serengeti (within Olduvai Gorge) was studied. Taphonomic analyses of this assemblage including skeletal part representation, bone density, breakage patterns and anatomical distribution of tooth marks, along with an ecological approach to the prey selection made by large carnivores of the Serengeti, were carried out. The results show that this bone assemblage may be the first lion-accumulated assemblage documented, although other carnivores (namely spotted hyenas) may have also intervened through postdepositional ravaging. This first faunal assemblage potentially created by lions constitutes a new framework for neotaphonomic studies. Since lions may accumulate carcasses under exceptional circumstances, such as those documented at the site reported here, this finding may have important consequences for interpretations of early archaeological and paleontological sites, which provide key information about human evolution. PMID:27144649

  19. Lions as Bone Accumulators? Paleontological and Ecological Implications of a Modern Bone Assemblage from Olduvai Gorge.

    PubMed

    Arriaza, Mari Carmen; Domínguez-Rodrigo, Manuel; Yravedra, José; Baquedano, Enrique

    2016-01-01

    Analytic models have been developed to reconstruct early hominin behaviour, especially their subsistence patterns, revealed mainly through taphonomic analyses of archaeofaunal assemblages. Taphonomic research is used to discern which agents (carnivores, humans or both) generate the bone assemblages recovered at archaeological sites. Taphonomic frameworks developed during the last decades show that the only large-sized carnivores in African biomes able to create bone assemblages are leopards and hyenas. A carnivore-made bone assemblage located in the short-grassland ecological unit of the Serengeti (within Olduvai Gorge) was studied. Taphonomic analyses of this assemblage including skeletal part representation, bone density, breakage patterns and anatomical distribution of tooth marks, along with an ecological approach to the prey selection made by large carnivores of the Serengeti, were carried out. The results show that this bone assemblage may be the first lion-accumulated assemblage documented, although other carnivores (namely spotted hyenas) may have also intervened through postdepositional ravaging. This first faunal assemblage potentially created by lions constitutes a new framework for neotaphonomic studies. Since lions may accumulate carcasses under exceptional circumstances, such as those documented at the site reported here, this finding may have important consequences for interpretations of early archaeological and paleontological sites, which provide key information about human evolution. PMID:27144649

  20. Toxic Takifugu pardalis eggs found in Takifugu niphobles gut: Implications for TTX accumulation in the pufferfish.

    PubMed

    Itoi, Shiro; Kozaki, Ao; Komori, Keitaro; Tsunashima, Tadasuke; Noguchi, Shunsuke; Kawane, Mitsuo; Sugita, Haruo

    2015-12-15

    Pufferfish (Takifugu spp.) possess a potent neurotoxin, tetrodotoxin (TTX). TTX has been detected in various organisms including food animals of pufferfish, and TTX-producing bacteria have been isolated from these animals. TTX in marine pufferfish accumulates in the pufferfish via the food web starting with marine bacteria. However, such accumulation is unlikely to account for the amount of TTX in the pufferfish body because of the minute amounts of TTX produced by marine bacteria. Therefore, the toxification process in pufferfish still remains unclear. In this article we report the presence of numerous Takifugu pardalis eggs in the intestinal contents of another pufferfish, Takifugu niphobles. The identity of T. pardalis being determined by direct sequencing for mitochondrial DNA. LC-MS/MS analysis revealed that the peak detected in the egg samples corresponded to TTX. Toxification experiments in recirculating aquaria demonstrated that cultured Takifugu rubripes quickly became toxic upon being fed toxic (TTX-containing) T. rubripes eggs. These results suggest that T. niphobles ingested the toxic eggs of another pufferfish T. pardalis to toxify themselves more efficiently via a TTX loop consisting of TTX-bearing organisms at a higher trophic level in the food web. PMID:26485535

  1. The Nitrogen Legacy: Evidence of Soil Nitrogen Accumulation in Anthropogenic Landscapes

    NASA Astrophysics Data System (ADS)

    Van Meter, K. J.; Basu, N. B.

    2013-12-01

    Human modification of the nitrogen (N) cycle has resulted in increased flows of reactive N, with some suggesting that planetary boundaries for maintaining human and ecosystem health have been exceeded. Persistence of large hypoxic zones in inland and coastal waters created by elevated concentrations of nitrate is one of the most significant impacts of such increased flows. While the need to manage these flows and their associated ecological impacts is recognized, best management practices to reduce stream N concentrations have had only limited success. Some have attributed this lack of success to an accumulation of legacy N stores from decades of fertilizer application. Nitrogen mass balance studies seem to suggest an ongoing retention of N within anthropogenic landscapes, but the exact form and location of this legacy N and the associated retention rates are subject to question. Here we introduce an unprecedented analysis of long-term soil data from the Mississippi River Basin (MRB) revealing significant increases in total N (TN) content. We show that TN accumulation for the MRB accounts for 49% of net anthropogenic N inputs (NANI), which complements previous work indicating that approximately 25% of net inputs are lost as riverine output. These findings significantly reduce the uncertainty associated with basin-level N retention. Further, our results demonstrate that, despite conventional wisdom of intensive agriculture leading to a depletion of TN, an accumulation of N is occurring in the deeper subsurface (25 - 100 cm) that compensates for depletion in the plow layer (0-25 cm). These legacy N stores may lead to time lags between changes in management practices and decreasing N concentrations in stream waters, thus resulting in multidecadal effects on water quality in agricultural watersheds.

  2. Cenozoic tectonic jumping and implications for hydrocarbon accumulation in basins in the East Asia Continental Margin

    NASA Astrophysics Data System (ADS)

    Suo, Yanhui; Li, Sanzhong; Yu, Shan; Somerville, Ian D.; Liu, Xin; Zhao, Shujuan; Dai, Liming

    2014-07-01

    Tectonic migration is a common geological process of basin formation and evolution. However, little is known about tectonic migration in the western Pacific margins. This paper focuses on the representative Cenozoic basins of East China and its surrounding seas in the western Pacific domain to discuss the phenomenon of tectonic jumping in Cenozoic basins, based on structural data from the Bohai Bay Basin, the South Yellow Sea Basin, the East China Sea Shelf Basin, and the South China Sea Continental Shelf Basin. The western Pacific active continental margin is the eastern margin of a global convergent system involving the Eurasian Plate, the Pacific Plate, and the Indian Plate. Under the combined effects of the India-Eurasia collision and retrogressive or roll-back subduction of the Pacific Plate, the western Pacific active continental margin had a wide basin-arc-trench system which migrated or ‘jumped’ eastward and further oceanward. This migration and jumping is characterized by progressive eastward younging of faulting, sedimentation, and subsidence within the basins. Owing to the tectonic migration, the geological conditions associated with hydrocarbon and gashydrate accumulation in the Cenozoic basins of East China and its adjacent seas also become progressively younger from west to east, showing eastward younging in the generation time of reservoirs, seals, traps, accumulations and preservation of hydrocarbon and gashydrate. Such a spatio-temporal distribution of Cenozoic hydrocarbon and gashydrate is significant for the oil, gas and gashydrate exploration in the East Asian Continental Margin. Finally, this study discusses the mechanism of Cenozoic intrabasinal and interbasinal tectonic migration in terms of interplate, intraplate and underplating processes. The migration or jumping regimes of three separate or interrelated events: (1) tectonism-magmatism, (2) basin formation, and (3) hydrocarbon-gashydrate accumulation are the combined effects of the

  3. Effect of cadmium accumulation on mineral nutrient levels in vegetable crops: potential implications for human health.

    PubMed

    Yang, Danping; Guo, Zhiqiang; Green, Iain D; Xie, Deti

    2016-10-01

    Consumption of vegetables is often the predominant route whereby humans are exposed to the toxic metal Cd. Health impacts arising from Cd consumption may be influenced by changes in the mineral nutrient content of vegetables, which may occur when plants are exposed to Cd. Here, we subjected model root (carrot) and leaf (lettuce) vegetables to soil Cd concentrations of 0.3, 1.5, 3.3, and 9.6 μg g(-1) for 10 weeks to investigate the effect of Cd exposure on Cd accumulation, growth performance, and mineral nutrient homeostasis. The findings demonstrated that Cd accumulation in lettuce (20.1-71.5 μg g(-1)) was higher than that in carrot (3.2-27.5 μg g(-1)), and accumulation exceeded the maximum permissible Cd concentration in vegetables when soil contained more than 3.3 μg g(-1) of Cd. There was a marked hormetic effect on carrot growth at a soil Cd concentration of 3.3 μg g(-1), but increasing the Cd concentration to 9.6 μg g(-1) caused decreased growth in both crops. Additionally, in most cases, there was a positive correlation between Cd and the mineral nutrient content of vegetables, which was due to physiological changes in the plants causing increased uptake and/or translocation. This may suggest a general mechanism whereby the plant compensated for disrupted mineral nutrient metabolism by increasing nutrient supply to its tissues. Increased nutrient levels could potentially offset some risks posed to humans by increased Cd levels in crops, and we therefore suggest that changes in mineral nutrient levels should be included more widely in the risk assessment of potentially toxic metal contamination. Graphical abstract The Cd concentration (μg g-1 in dry matter) in the root, shoot and translocation factor (TF) of Cd from root to shoot in the carrot and lettuce, and the percentage of root Cd to the gross Cd contents (%) in carrot (C) and lettuce (D) exposed to soil Cd (0 (control), 1, 3, and 9 μg g-1) for 70 days. Values are means ± SD (n = 5

  4. Effect of cadmium accumulation on mineral nutrient levels in vegetable crops: potential implications for human health.

    PubMed

    Yang, Danping; Guo, Zhiqiang; Green, Iain D; Xie, Deti

    2016-10-01

    Consumption of vegetables is often the predominant route whereby humans are exposed to the toxic metal Cd. Health impacts arising from Cd consumption may be influenced by changes in the mineral nutrient content of vegetables, which may occur when plants are exposed to Cd. Here, we subjected model root (carrot) and leaf (lettuce) vegetables to soil Cd concentrations of 0.3, 1.5, 3.3, and 9.6 μg g(-1) for 10 weeks to investigate the effect of Cd exposure on Cd accumulation, growth performance, and mineral nutrient homeostasis. The findings demonstrated that Cd accumulation in lettuce (20.1-71.5 μg g(-1)) was higher than that in carrot (3.2-27.5 μg g(-1)), and accumulation exceeded the maximum permissible Cd concentration in vegetables when soil contained more than 3.3 μg g(-1) of Cd. There was a marked hormetic effect on carrot growth at a soil Cd concentration of 3.3 μg g(-1), but increasing the Cd concentration to 9.6 μg g(-1) caused decreased growth in both crops. Additionally, in most cases, there was a positive correlation between Cd and the mineral nutrient content of vegetables, which was due to physiological changes in the plants causing increased uptake and/or translocation. This may suggest a general mechanism whereby the plant compensated for disrupted mineral nutrient metabolism by increasing nutrient supply to its tissues. Increased nutrient levels could potentially offset some risks posed to humans by increased Cd levels in crops, and we therefore suggest that changes in mineral nutrient levels should be included more widely in the risk assessment of potentially toxic metal contamination. Graphical abstract The Cd concentration (μg g-1 in dry matter) in the root, shoot and translocation factor (TF) of Cd from root to shoot in the carrot and lettuce, and the percentage of root Cd to the gross Cd contents (%) in carrot (C) and lettuce (D) exposed to soil Cd (0 (control), 1, 3, and 9 μg g-1) for 70 days. Values are means ± SD (n = 5).

  5. Teaching evidence-based practice: implications for psychology.

    PubMed

    Collins, Frank L; Leffingwell, Thad R; Belar, Cynthia D

    2007-07-01

    A movement advocating the use of evidence-based practice (EBP) is increasingly influencing health care and the practice of psychology. Thus, teaching evidence-based practice in psychology (EBPP) is critical to the preparation of future health service psychologists. In this article, the authors address common myths associated with EBP, propose core components involved in teaching EBPP, and describe an example of how such training can be incorporated into a professional psychology education and training curriculum.

  6. Lifespan mercury accumulation pattern in Liza aurata : Evidence from two southern European estuaries

    NASA Astrophysics Data System (ADS)

    Tavares, S.; Oliveira, H.; Coelho, J. P.; Pereira, M. E.; Duarte, A. C.; Pardal, M. A.

    2011-10-01

    Mercury accumulation throughout the lifespan of Liza aurata (Risso, 1810) was analysed in four tissues (muscle, gills, liver and brain) in two southern European coastal ecosystems with distinct mercury contamination. Specimens from four to five age classes were captured in two sampling sites in the Ria de Aveiro (Laranjo bay and Mira), a system historically contaminated by industrial mercury, and in one site in the Mondego estuary, assumed as a mercury-free ecosystem. Mercury concentration in all tissues was found to be significantly higher in the Ria de Aveiro (Laranjo bay) compared to the Mondego, in accordance with the environmental contamination (water, sediments and suspended particulate matter). Significant differences inside the Ria de Aveiro (between the Mira and Laranjo bay) were only detected in the liver. This tissue registered the highest levels of mercury (ranging from 0.11 to 4.2 μg g -1 ) in all sampling sites, followed by muscle, brain, and gills. In all sampling sites and tissues was denoted a mercury dilution pattern along the lifecycle (except in liver at the Mondego, the reference area where the concentrations are always very low). An exponential trend was found in the metal age variation patterns in Laranjo (the most contaminated area) and a linear trend in the Mira and the Mondego (the least contaminated areas). Organic mercury concentration in muscle generally accounted for over 95% of total mercury concentration, and followed the same accumulation pattern of total mercury. This fish species is of lesser importance in mercury transfer to adjacent coastal areas and although the consumption of fish from Laranjo may present some risk for the humans, this risk decreases with fish age/size.

  7. EXTERNAL MASS ACCUMULATION ONTO CORE POTENTIALS: IMPLICATIONS FOR STAR CLUSTERS, GALAXIES, AND GALAXY CLUSTERS

    SciTech Connect

    Naiman, J. P.; Ramirez-Ruiz, E.; Lin, D. N. C.

    2011-07-01

    Accretion studies have been focused on the flow around bodies with point mass gravitational potentials, but few general results are available for non-point mass distributions. Here, we study the accretion flow onto non-divergent, core potentials moving through a background medium. We use Plummer and Hernquist potentials as examples to study gas accretion onto star clusters, dwarf and large galaxy halos, and galaxy clusters in a variety of astrophysical environments. The general conditions required for a core potential to collectively accrete large quantities of gas from the external medium are derived using both simulations and analytic results. The consequences of large mass accumulation in galaxy nuclei, dwarf galaxies, and star clusters are twofold. First, if the gas cools effectively star formation can be triggered, generating new stellar members in the system. Second, if the collective potential of the system is able to alter the ambient gas properties before the gas is accreted onto the individual core members, the augmented mass supply rates could significantly alter the state of the various accreting stellar populations and result in an enhanced central black hole accretion luminosity.

  8. Nonlinear Learning Underpinning Pedagogy: Evidence, Challenges, and Implications

    ERIC Educational Resources Information Center

    Chow, Jia Yi

    2013-01-01

    This article provides a brief overview of the framework of nonlinear pedagogy and evidence emanating from motor learning literature that underpins a nonlinear pedagogical approach. In addition, challenges for nonlinear pedagogy and a discussion on how nonlinear pedagogy support the work of physical education (PE) teachers will be shared. Evidence…

  9. First evidence of accumulation of mega boulders on the Mediterranean rocky coast of Provence (southern France)

    NASA Astrophysics Data System (ADS)

    Vella, C.; Demory, F.; Canut, V.; Dussouillez, P.; Fleury, T. J.

    2011-03-01

    An accumulation of boulders was recently discovered along the rocky coast of the Gulf of Fos located in Provence, in an area exposed to a south-westerly wave regime. The coast around this locality forms the western extremity of the calcareous Nerthe range between Marseille and the Rhône Delta. Several mega blocks are scattered to a distance of 30 m behind the coast line. The largest block (33.5 tonnes) has been transported about 39 m inland, up to about 2 m a.s.l. On the Mediterranean coast, the origin of such blocks is often attributed to tsunami-generated waves, but in the case examined here, although the origin is unclear, the differences in surface state between boulders indicates several events generated by south-westerly storms. Radiocarbon dating on several different shells collected from seven different boulders yields a wide dispersion of ages ranging from 4000 BP to the Modern Period. The differences in surface appearance, as well as the differences of fauna conservation and surface coloration, in some cases in a very fresh state, along with the dispersion of radiocarbon ages, suggest that historic storm events have affected these megablocks.

  10. No Evidence of Elevated Germline Mutation Accumulation Under Oxidative Stress in Caenorhabditis elegans

    PubMed Central

    Joyner-Matos, Joanna; Bean, Laura C.; Richardson, Heidi L.; Sammeli, Tammy; Baer, Charles F.

    2011-01-01

    Variation in rates of molecular evolution has been attributed to numerous, interrelated causes, including metabolic rate, body size, and generation time. Speculation concerning the influence of metabolic rate on rates of evolution often invokes the putative mutagenic effects of oxidative stress. To isolate the effects of oxidative stress on the germline from the effects of metabolic rate, generation time, and other factors, we allowed mutations to accumulate under relaxed selection for 125 generations in two strains of the nematode Caenorhabditis elegans, the canonical wild-type strain (N2) and a mutant strain with elevated steady-state oxidative stress (mev-1). Contrary to our expectation, the mutational decline in fitness did not differ between N2 and mev-1. This result suggests that the mutagenic effects of oxidative stress in C. elegans are minor relative to the effects of other types of mutations, such as errors during DNA replication. However, mev-1 MA lines did go extinct more frequently than wild-type lines; some possible explanations for the difference in extinction rate are discussed. PMID:21979932

  11. Eye-hand coordination during a double-step task: evidence for a common stochastic accumulator.

    PubMed

    Gopal, Atul; Murthy, Aditya

    2015-09-01

    Many studies of reaching and pointing have shown significant spatial and temporal correlations between eye and hand movements. Nevertheless, it remains unclear whether these correlations are incidental, arising from common inputs (independent model); whether these correlations represent an interaction between otherwise independent eye and hand systems (interactive model); or whether these correlations arise from a single dedicated eye-hand system (common command model). Subjects were instructed to redirect gaze and pointing movements in a double-step task in an attempt to decouple eye-hand movements and causally distinguish between the three architectures. We used a drift-diffusion framework in the context of a race model, which has been previously used to explain redirect behavior for eye and hand movements separately, to predict the pattern of eye-hand decoupling. We found that the common command architecture could best explain the observed frequency of different eye and hand response patterns to the target step. A common stochastic accumulator for eye-hand coordination also predicts comparable variances, despite significant difference in the means of the eye and hand reaction time (RT) distributions, which we tested. Consistent with this prediction, we observed that the variances of the eye and hand RTs were similar, despite much larger hand RTs (∼90 ms). Moreover, changes in mean eye RTs, which also increased eye RT variance, produced a similar increase in mean and variance of the associated hand RT. Taken together, these data suggest that a dedicated circuit underlies coordinated eye-hand planning.

  12. Mercury (Hg) accumulation in terrestrial carbon (C) reservoirs: magnitude, spatial patterns, fate upon C losses, and implications of global change

    NASA Astrophysics Data System (ADS)

    Obrist, D.; Johnson, D. W.; Lindberg, S. E.; Luo, Y.

    2012-04-01

    that at a global scale as much as 4.5 x 106 Mg of Hg is sequestered in soil organic C pools, and propose that climate-induced changes in terrestrial C have direct implications on terrestrial Hg reservoirs. Using organic C as a matrix to quantify surface reservoir accumulation of atmospheric pollutants may also be applicable to other compounds with strong affinities to organic C, including polychlorinated biphenyls (PCB), polycyclic aromatic hydrocarbons (PAHs), and polybrominated diphenyl ethers (PBDEs).

  13. Psoriasis and Metabolic Syndrome – scientific evidence and therapeutic implications

    PubMed Central

    Voiculescu, VM; Lupu, M; Papagheorghe, L; Giurcaneanu, C; Micu, E

    2014-01-01

    Psoriasis is a chronic inflammatory disease, predominantly affecting the skin, being included in the group of Immune Mediated Inflammatory Diseases. Growing evidence from the last 10 years suggests that several systemic conditions like metabolic syndrome, cardiovascular disease, diabetes, psychological disorders or inflammatory bowel disease are prevalent in psoriasis patients. The linker might be the chronic secretion of pro-inflammatory cytokines. In this current review, the scientific evidence that explains the relationship between psoriasis and the metabolic syndrome in particular will be addressed, as the metabolic syndrome comprises a group of risk factors for cardiovascular disease, thus offering an overall picture of the systemic involvement in psoriasis. An integrated approach, with an early detection and treatment of the components of the metabolic syndrome, are important steps in psoriasis management. Attention should be paid on influence of psoriasis treatment upon comorbidities and vice-versa. PMID:25713604

  14. Psoriasis and Metabolic Syndrome--scientific evidence and therapeutic implications.

    PubMed

    Voiculescu, V M; Lupu, M; Papagheorghe, L; Giurcaneanu, C; Micu, E

    2014-01-01

    Psoriasis is a chronic inflammatory disease, predominantly affecting the skin, being included in the group of Immune Mediated Inflammatory Diseases. Growing evidence from the last 10 years suggests that several systemic conditions like metabolic syndrome, cardiovascular disease, diabetes, psychological disorders or inflammatory bowel disease are prevalent in psoriasis patients. The linker might be the chronic secretion of pro-inflammatory cytokines. In this current review, the scientific evidence that explains the relationship between psoriasis and the metabolic syndrome in particular will be addressed, as the metabolic syndrome comprises a group of risk factors for cardiovascular disease, thus offering an overall picture of the systemic involvement in psoriasis. An integrated approach, with an early detection and treatment of the components of the metabolic syndrome, are important steps in psoriasis management. Attention should be paid on influence of psoriasis treatment upon comorbidities and vice-versa.

  15. Assessment of cadmium accumulation, toxicity, and tolerance in Brassicaceae and Fabaceae plants--implications for phytoremediation.

    PubMed

    Anjum, Naser A; Umar, Shahid; Iqbal, Muhammad

    2014-09-01

    This study, based on a greenhouse pot culture experiment conducted with 15-day-old rapeseed (Brassica campestris L. cv. Pusa Gold; family Brassicaceae) and moong bean (Vigna radiata L. Wilczek cv. Pusa Ratna; family Fabaceae) plants treated with cadmium (Cd) concentrations (0, 50, and 100 mg kg(-1) soil), investigates their potential for Cd accumulation and tolerance, and dissects the underlying basic physiological/biochemical mechanisms. In both species, plant dry mass decreased, while Cd concentration of both root and shoot increased with increase in soil Cd. Roots harbored a higher amount of Cd (vs. shoot) in B. campestris, while the reverse applied to V. radiata. By comparison, root Cd concentration was higher in B. campestris than in V. radiata. The high Cd concentrations in B. campestris roots and V. radiata shoots led to significant elevation in oxidative indices, as measured in terms of electrolyte leakage, H2O2 content, and lipid peroxidation. Both plants displayed differential adaptation strategies to counteract the Cd burden-caused anomalies in their roots and shoots. In B. campestris, increasing Cd burden led to a significantly decreased reduced glutathione (GSH) content but a significant increase in activities of GSH reductase (GR), GSH peroxidase (GPX), and GSH sulfotransferase (GST). However, in V. radiata, increasing Cd burden caused significant increase in GSH content and GR activity, but a significant decline in activities of GPX and GST. Cross talks on Cd burden of tissues and the adapted Cd tolerance strategies against Cd burden-accrued toxicity indicated that B. campestris and V. radiata are good Cd stabilizer and Cd extractor, respectively, wherein a fine tuning among the major components (GR, GPX, GST, GSH) of the GSH redox system helped the plants to counteract differentially the Cd load-induced anomalies in tissues. On the whole, the physiological/biochemical characterization of the B. campestris and V. radiata responses to varying Cd

  16. Assessment of cadmium accumulation, toxicity, and tolerance in Brassicaceae and Fabaceae plants--implications for phytoremediation.

    PubMed

    Anjum, Naser A; Umar, Shahid; Iqbal, Muhammad

    2014-09-01

    This study, based on a greenhouse pot culture experiment conducted with 15-day-old rapeseed (Brassica campestris L. cv. Pusa Gold; family Brassicaceae) and moong bean (Vigna radiata L. Wilczek cv. Pusa Ratna; family Fabaceae) plants treated with cadmium (Cd) concentrations (0, 50, and 100 mg kg(-1) soil), investigates their potential for Cd accumulation and tolerance, and dissects the underlying basic physiological/biochemical mechanisms. In both species, plant dry mass decreased, while Cd concentration of both root and shoot increased with increase in soil Cd. Roots harbored a higher amount of Cd (vs. shoot) in B. campestris, while the reverse applied to V. radiata. By comparison, root Cd concentration was higher in B. campestris than in V. radiata. The high Cd concentrations in B. campestris roots and V. radiata shoots led to significant elevation in oxidative indices, as measured in terms of electrolyte leakage, H2O2 content, and lipid peroxidation. Both plants displayed differential adaptation strategies to counteract the Cd burden-caused anomalies in their roots and shoots. In B. campestris, increasing Cd burden led to a significantly decreased reduced glutathione (GSH) content but a significant increase in activities of GSH reductase (GR), GSH peroxidase (GPX), and GSH sulfotransferase (GST). However, in V. radiata, increasing Cd burden caused significant increase in GSH content and GR activity, but a significant decline in activities of GPX and GST. Cross talks on Cd burden of tissues and the adapted Cd tolerance strategies against Cd burden-accrued toxicity indicated that B. campestris and V. radiata are good Cd stabilizer and Cd extractor, respectively, wherein a fine tuning among the major components (GR, GPX, GST, GSH) of the GSH redox system helped the plants to counteract differentially the Cd load-induced anomalies in tissues. On the whole, the physiological/biochemical characterization of the B. campestris and V. radiata responses to varying Cd

  17. Evidence of salt accumulation in beach intertidal zone due to evaporation

    NASA Astrophysics Data System (ADS)

    Geng, Xiaolong; Boufadel, Michel C.; Jackson, Nancy L.

    2016-08-01

    In coastal environments, evaporation is an important driver of subsurface salinity gradients in marsh systems. However, it has not been addressed in the intertidal zone of sandy beaches. Here, we used field data on an estuarine beach foreshore with numerical simulations to show that evaporation causes upper intertidal zone pore-water salinity to be double that of seawater. We found the increase in pore-water salinity mainly depends on air temperature and relative humidity, and tide and wave actions dilute a fraction of the high salinity plume, resulting in a complex process. This is in contrast to previous studies that consider seawater as the most saline source to a coastal aquifer system, thereby concluding that seawater infiltration always increases pore-water salinity by seawater-groundwater mixing dynamics. Our results demonstrate the combined effects of evaporation and tide and waves on subsurface salinity distribution on a beach face. We anticipate our quantitative investigation will shed light on the studies of salt-affected biological activities in the intertidal zone. It also impacts our understanding of the impact of global warming; in particular, the increase in temperature does not only shift the saltwater landward, but creates a different salinity distribution that would have implications on intertidal biological zonation.

  18. Evidence of salt accumulation in beach intertidal zone due to evaporation

    PubMed Central

    Geng, Xiaolong; Boufadel, Michel C.; Jackson, Nancy L.

    2016-01-01

    In coastal environments, evaporation is an important driver of subsurface salinity gradients in marsh systems. However, it has not been addressed in the intertidal zone of sandy beaches. Here, we used field data on an estuarine beach foreshore with numerical simulations to show that evaporation causes upper intertidal zone pore-water salinity to be double that of seawater. We found the increase in pore-water salinity mainly depends on air temperature and relative humidity, and tide and wave actions dilute a fraction of the high salinity plume, resulting in a complex process. This is in contrast to previous studies that consider seawater as the most saline source to a coastal aquifer system, thereby concluding that seawater infiltration always increases pore-water salinity by seawater-groundwater mixing dynamics. Our results demonstrate the combined effects of evaporation and tide and waves on subsurface salinity distribution on a beach face. We anticipate our quantitative investigation will shed light on the studies of salt-affected biological activities in the intertidal zone. It also impacts our understanding of the impact of global warming; in particular, the increase in temperature does not only shift the saltwater landward, but creates a different salinity distribution that would have implications on intertidal biological zonation. PMID:27511713

  19. Evidence of salt accumulation in beach intertidal zone due to evaporation.

    PubMed

    Geng, Xiaolong; Boufadel, Michel C; Jackson, Nancy L

    2016-01-01

    In coastal environments, evaporation is an important driver of subsurface salinity gradients in marsh systems. However, it has not been addressed in the intertidal zone of sandy beaches. Here, we used field data on an estuarine beach foreshore with numerical simulations to show that evaporation causes upper intertidal zone pore-water salinity to be double that of seawater. We found the increase in pore-water salinity mainly depends on air temperature and relative humidity, and tide and wave actions dilute a fraction of the high salinity plume, resulting in a complex process. This is in contrast to previous studies that consider seawater as the most saline source to a coastal aquifer system, thereby concluding that seawater infiltration always increases pore-water salinity by seawater-groundwater mixing dynamics. Our results demonstrate the combined effects of evaporation and tide and waves on subsurface salinity distribution on a beach face. We anticipate our quantitative investigation will shed light on the studies of salt-affected biological activities in the intertidal zone. It also impacts our understanding of the impact of global warming; in particular, the increase in temperature does not only shift the saltwater landward, but creates a different salinity distribution that would have implications on intertidal biological zonation. PMID:27511713

  20. Evidence of salt accumulation in beach intertidal zone due to evaporation.

    PubMed

    Geng, Xiaolong; Boufadel, Michel C; Jackson, Nancy L

    2016-08-11

    In coastal environments, evaporation is an important driver of subsurface salinity gradients in marsh systems. However, it has not been addressed in the intertidal zone of sandy beaches. Here, we used field data on an estuarine beach foreshore with numerical simulations to show that evaporation causes upper intertidal zone pore-water salinity to be double that of seawater. We found the increase in pore-water salinity mainly depends on air temperature and relative humidity, and tide and wave actions dilute a fraction of the high salinity plume, resulting in a complex process. This is in contrast to previous studies that consider seawater as the most saline source to a coastal aquifer system, thereby concluding that seawater infiltration always increases pore-water salinity by seawater-groundwater mixing dynamics. Our results demonstrate the combined effects of evaporation and tide and waves on subsurface salinity distribution on a beach face. We anticipate our quantitative investigation will shed light on the studies of salt-affected biological activities in the intertidal zone. It also impacts our understanding of the impact of global warming; in particular, the increase in temperature does not only shift the saltwater landward, but creates a different salinity distribution that would have implications on intertidal biological zonation.

  1. Error awareness revisited: accumulation of multimodal evidence from central and autonomic nervous systems.

    PubMed

    Wessel, Jan R; Danielmeier, Claudia; Ullsperger, Markus

    2011-10-01

    The differences between erroneous actions that are consciously perceived as errors and those that go unnoticed have recently become an issue in the field of performance monitoring. In EEG studies, error awareness has been suggested to influence the error positivity (Pe) of the response-locked event-related brain potential, a positive voltage deflection prominent approximately 300 msec after error commission, whereas the preceding error-related negativity (ERN) seemed to be unaffected by error awareness. Erroneous actions, in general, have been shown to promote several changes in ongoing autonomic nervous system (ANS) activity, yet such investigations have only rarely taken into account the question of subjective error awareness. In the first part of this study, heart rate, pupillometry, and EEG were recorded during an antisaccade task to measure autonomic arousal and activity of the CNS separately for perceived and unperceived errors. Contrary to our expectations, we observed differences in both Pe and ERN with respect to subjective error awareness. This was replicated in a second experiment, using a modified version of the same task. In line with our predictions, only perceived errors provoke the previously established post-error heart rate deceleration. Also, pupil size yields a more prominent dilatory effect after an erroneous saccade, which is also significantly larger for perceived than unperceived errors. On the basis of the ERP and ANS results as well as brain-behavior correlations, we suggest a novel interpretation of the implementation and emergence of error awareness in the brain. In our framework, several systems generate input signals (e.g., ERN, sensory input, proprioception) that influence the emergence of error awareness, which is then accumulated and presumably reflected in later potentials, such as the Pe.

  2. Using Time-Varying Evidence to Test Models of Decision Dynamics: Bounded Diffusion vs. the Leaky Competing Accumulator Model.

    PubMed

    Tsetsos, Konstantinos; Gao, Juan; McClelland, James L; Usher, Marius

    2012-01-01

    When people make decisions, do they give equal weight to evidence arriving at different times? A recent study (Kiani et al., 2008) using brief motion pulses (superimposed on a random moving dot display) reported a primacy effect: pulses presented early in a motion observation period had a stronger impact than pulses presented later. This observation was interpreted as supporting the bounded diffusion (BD) model and ruling out models in which evidence accumulation is subject to leakage or decay of early-arriving information. We use motion pulses and other manipulations of the timing of the perceptual evidence in new experiments and simulations that support the leaky competing accumulator (LCA) model as an alternative to the BD model. While the LCA does include leakage, we show that it can exhibit primacy as a result of competition between alternatives (implemented via mutual inhibition), when the inhibition is strong relative to the leak. Our experiments replicate the primacy effect when participants must be prepared to respond quickly at the end of a motion observation period. With less time pressure, however, the primacy effect is much weaker. For 2 (out of 10) participants, a primacy bias observed in trials where the motion observation period is short becomes weaker or reverses (becoming a recency effect) as the observation period lengthens. Our simulation studies show that primacy is equally consistent with the LCA or with BD. The transition from primacy-to-recency can also be captured by the LCA but not by BD. Individual differences and relations between the LCA and other models are discussed.

  3. Accumulation of impact markers in desert wetlands and implications for the Younger Dryas impact hypothesis

    PubMed Central

    Pigati, Jeffrey S.; Latorre, Claudio; Rech, Jason A.; Betancourt, Julio L.; Martínez, Katherine E.; Budahn, James R.

    2012-01-01

    The Younger Dryas impact hypothesis contends that an extraterrestrial object exploded over North America at 12.9 ka, initiating the Younger Dryas cold event, the extinction of many North American megafauna, and the demise of the Clovis archeological culture. Although the exact nature and location of the proposed impact or explosion remain unclear, alleged evidence for the fallout comes from multiple sites across North America and a site in Belgium. At 6 of the 10 original sites (excluding the Carolina Bays), elevated concentrations of various “impact markers” were found in association with black mats that date to the onset of the Younger Dryas. Black mats are common features in paleowetland deposits and typically represent shallow marsh environments. In this study, we investigated black mats ranging in age from approximately 6 to more than 40 ka in the southwestern United States and the Atacama Desert of northern Chile. At 10 of 13 sites, we found elevated concentrations of iridium in bulk and magnetic sediments, magnetic spherules, and/or titanomagnetite grains within or at the base of black mats, regardless of their age or location, suggesting that elevated concentrations of these markers arise from processes common to wetland systems, and not a catastrophic extraterrestrial impact event. PMID:22529347

  4. Gamma-Ray bursts: accumulating afterglow implications, progenitor clues, and prospects.

    PubMed

    Mészáros, P

    2001-01-01

    Gamma-ray bursts (GRBs) are sudden, intense flashes of gamma rays that, for a few blinding seconds, light up in an otherwise fairly dark gamma-ray sky. They are detected at the rate of about once a day, and while they are on, they outshine every other gamma-ray source in the sky, including the sun. Major advances have been made in the last 3 or 4 years, including the discovery of slowly fading x-ray, optical, and radio afterglows of GRBs, the identification of host galaxies at cosmological distances, and evidence showing that many GRBs are associated with star-forming regions and possibly supernovae. Progress has been made in understanding how the GRB and afterglow radiation arises in terms of a relativistic fireball shock model. These advances have opened new vistas and questions on the nature of the central engine, the identity of their progenitors, the effects of the environment, and their possible gravitational wave, cosmic ray, and neutrino luminosity. The debates on these issues indicate that GRBs remain among the most mysterious puzzles in astrophysics. PMID:11141551

  5. Accumulation of impact markers in desert wetlands and implications for the Younger Dryas impact hypothesis.

    PubMed

    Pigati, Jeffrey S; Latorre, Claudio; Rech, Jason A; Betancourt, Julio L; Martínez, Katherine E; Budahn, James R

    2012-05-01

    The Younger Dryas impact hypothesis contends that an extraterrestrial object exploded over North America at 12.9 ka, initiating the Younger Dryas cold event, the extinction of many North American megafauna, and the demise of the Clovis archeological culture. Although the exact nature and location of the proposed impact or explosion remain unclear, alleged evidence for the fallout comes from multiple sites across North America and a site in Belgium. At 6 of the 10 original sites (excluding the Carolina Bays), elevated concentrations of various "impact markers" were found in association with black mats that date to the onset of the Younger Dryas. Black mats are common features in paleowetland deposits and typically represent shallow marsh environments. In this study, we investigated black mats ranging in age from approximately 6 to more than 40 ka in the southwestern United States and the Atacama Desert of northern Chile. At 10 of 13 sites, we found elevated concentrations of iridium in bulk and magnetic sediments, magnetic spherules, and/or titanomagnetite grains within or at the base of black mats, regardless of their age or location, suggesting that elevated concentrations of these markers arise from processes common to wetland systems, and not a catastrophic extraterrestrial impact event.

  6. Gamma-Ray bursts: accumulating afterglow implications, progenitor clues, and prospects.

    PubMed

    Mészáros, P

    2001-01-01

    Gamma-ray bursts (GRBs) are sudden, intense flashes of gamma rays that, for a few blinding seconds, light up in an otherwise fairly dark gamma-ray sky. They are detected at the rate of about once a day, and while they are on, they outshine every other gamma-ray source in the sky, including the sun. Major advances have been made in the last 3 or 4 years, including the discovery of slowly fading x-ray, optical, and radio afterglows of GRBs, the identification of host galaxies at cosmological distances, and evidence showing that many GRBs are associated with star-forming regions and possibly supernovae. Progress has been made in understanding how the GRB and afterglow radiation arises in terms of a relativistic fireball shock model. These advances have opened new vistas and questions on the nature of the central engine, the identity of their progenitors, the effects of the environment, and their possible gravitational wave, cosmic ray, and neutrino luminosity. The debates on these issues indicate that GRBs remain among the most mysterious puzzles in astrophysics.

  7. Accumulation of impact markers in desert wetlands and implications for the Younger Dryas impact hypothesis

    USGS Publications Warehouse

    Pigati, Jeffrey S.; Latorre, Claudio; Rech, Jason A.; Betancourt, Julio L.; Martinez, Katherine E.; Budahn, James R.

    2012-01-01

    The Younger Dryas impact hypothesis contends that an extraterrestrial object exploded over North America at 12.9 ka, initiating the Younger Dryas cold event, the extinction of many North American megafauna, and the demise of the Clovis archeological culture. Although the exact nature and location of the proposed impact or explosion remain unclear, alleged evidence for the fallout comes from multiple sites across North America and a site in Belgium. At 6 of the 10 original sites (excluding the Carolina Bays), elevated concentrations of various "impact markers" were found in association with black mats that date to the onset of the Younger Dryas. Black mats are common features in paleowetland deposits and typically represent shallow marsh environments. In this study, we investigated black mats ranging in age from approximately 6 to more than 40 ka in the southwestern United States and the Atacama Desert of northern Chile. At 10 of 13 sites, we found elevated concentrations of iridium in bulk and magnetic sediments, magnetic spherules, and/or titanomagnetite grains within or at the base of black mats, regardless of their age or location, suggesting that elevated concentrations of these markers arise from processes common to wetland systems, and not a catastrophic extraterrestrial impact event.

  8. Accumulation of impact markers in desert wetlands and implications for the Younger Dryas impact hypothesis.

    PubMed

    Pigati, Jeffrey S; Latorre, Claudio; Rech, Jason A; Betancourt, Julio L; Martínez, Katherine E; Budahn, James R

    2012-05-01

    The Younger Dryas impact hypothesis contends that an extraterrestrial object exploded over North America at 12.9 ka, initiating the Younger Dryas cold event, the extinction of many North American megafauna, and the demise of the Clovis archeological culture. Although the exact nature and location of the proposed impact or explosion remain unclear, alleged evidence for the fallout comes from multiple sites across North America and a site in Belgium. At 6 of the 10 original sites (excluding the Carolina Bays), elevated concentrations of various "impact markers" were found in association with black mats that date to the onset of the Younger Dryas. Black mats are common features in paleowetland deposits and typically represent shallow marsh environments. In this study, we investigated black mats ranging in age from approximately 6 to more than 40 ka in the southwestern United States and the Atacama Desert of northern Chile. At 10 of 13 sites, we found elevated concentrations of iridium in bulk and magnetic sediments, magnetic spherules, and/or titanomagnetite grains within or at the base of black mats, regardless of their age or location, suggesting that elevated concentrations of these markers arise from processes common to wetland systems, and not a catastrophic extraterrestrial impact event. PMID:22529347

  9. Evidence and biogeochemical implications for glacially-derived sediments in an active margin cold seep

    USGS Publications Warehouse

    Pohlman, John W.; Riedel, Michael; Novosel, Ivana; Bauer, James E.; Canuel, Elizabeth A.; Paull, Charles K.; Coffin, Richard B.; Grabowski, Kenneth S.; Knies, David L.; Hyndman, Roy D.; Spence, George D.

    2011-01-01

    Delineating sediment organic matter origins and sediment accumulation rates at gas hydratebearing and hydrocarbon seeps is complicated by the microbial transfer of 13C-depleted and 14Cdepleted methane carbon into sedimentary pools. Sediment 13C and 14C measurements from four cores recovered at Bullseye vent on the northern Cascadia margin are used to identify methane carbon assimilation into different carbon pools. While the total organic carbon (TOC) is mostly unaltered and primarily terrigenous in origin, planktonic foraminifera and the bulk carbonate display evidence of methane overprinting. Mass balance models are applied to determine the extent to which methane overprinting increased the radiocarbon ages of the biogenic foraminifera. The corrected and calibrated foraminifera ages between sediment depths of 70 and 573 cm are from 14.9 to 15.9 ka BP, which coincides with the retreat of the late Quaternary Cordilleran Ice Sheet from Vancouver Island. Uniform TOC _13C values of -24.5 ± 0.5‰ from the upper 8 meters of sediment at Bullseye vent suggest all cored material is Pleistocene-derived glacimarine material deposited as the ice edge retreated landward. Bullseye vent is located within an uplifted sediment block isolated from turbidite deposition and has been a site of non-deposition since the ice sheet retreated from the shelf. Biogeochemical implications of seep sediments being dominated by aged, organic-poor (<0.4 wt% TOC) material are that methane is the primary energy source, and microbes directly and indirectly associated with the anaerobic oxidation of methane (AOM) will dominate the seep microbial community.

  10. Evidence and implications of shock metamorphism in lunar samples.

    PubMed

    Short, N M

    1970-01-30

    Lunar microbreccias and loose regolith materials contain abundant evidence of shock metamorphism related to crater-forming meteorite impacts. Diagnostic shock effects include (i) planar features in a silica phase and feldspars, and lamellae in clinopyroxene, (ii) thetomorphic feldspar glass, (iii) heterogeneous glasses of rock and mineral composition, (iv) distinctive recrystallization textures, and (v) characteristic changes in crystal structure as indicated by x-ray diffraction analysis and measurements of refractive index. The microbreccias are produced from regolith materials (ejected fromz craters) by shock lithification. Some feldsparrich fragments may represent ejecta introduced from nonlocal sources, such as the lunar highlands.

  11. Geochemical evidence for modern sediment accumulation on the continental shelf off southern New England

    USGS Publications Warehouse

    Bothner, Michael H.; Spiker, E. C.; Johnson, P. P.; Rendigs, R. R.; Aruscavage, P. J.

    1981-01-01

    An area of fine-grained sediment approximately 170 km x 74 km in size, located in water depths between 60 m and 150 m, south of Martha's Vineyard, Mass., is a site of modern sediment deposition. The 14C ages systematically increase with sediment depth from about 1,300 years B.P. at the surface to 8,000-10,000 years B.P. at the depth of maximum core penetration. The old age for the surface sediments probably results from a combination of deposition of old carbon and faunal mixing. In the finest sediments, the sedimentation rates were approximately 130 cm/1,000 yrs when deposition began and have decreased to about 25 cm/1,000 yrs. The decreasing sedimentation rate reflects a diminishing source of fine sediments, which presumably came from the Georges Bank and Nantucket Shoals area. Inventories of excess 210Pb in undisturbed cores average 70 dpm/cm2 (disintegrations per minute per square centimeter), more than two times higher than the flux of 210Pb from the atmosphere and from 226Ra decay in the overlying water. This additional influx of 210Pb either must be with new fine-grained sediment material or from solutions that are stripped of their 210Pb by particulates in the bottom nepheloid layer. Stable Pb concentrations in surface sediments are about 28 ppm, as much as two times higher than concentrations at depth. The high accumulation rates, 210Pb inventories, and trace-metal profiles imply that this area is a modern sink for fine-grained sediments and for pollutants associated with particulate matter in the water column. To our knowledge, this is the only site of present-day natural deposition on the Continental Shelf off the eastern United States, exclusive of the Gulf of Maine. Because the net currents on the outer half of this Continental Shelf flow from northeast to southwest, this fine-grained deposit may receive its sediments and possible contaminants from the Nantucket Shoals and Georges Bank regions.

  12. Dead zones in colloidal quantum dot photovoltaics: evidence and implications.

    PubMed

    Barkhouse, D Aaron R; Kramer, Illan J; Wang, Xihua; Sargent, Edward H

    2010-09-13

    In order to fabricate photovoltaic (PV) cells incorporating light-trapping electrodes, flexible foil substrates, or more than one junction, illumination through the top-contact (i.e.: non-substrate) side of a photovoltaic device is desirable. We investigate the relative collection efficiency for illumination through the top vs. bottom of PbS colloidal quantum dot (CQD) PV devices. The external quantum efficiency spectra of FTO/TiO₂/PbS CQD/ITO PV devices with various PbS layer thicknesses were measured for illumination through either the top (ITO) or bottom (FTO) contacts. By comparing the relative shapes and intensities of these spectra with those calculated from an estimation of the carrier generation profile and the internal quantum efficiency as a function of distance from the TiO₂ interface in the devices, a substantial dead zone, where carrier extraction is dramatically reduced, is identified near the ITO top contact. The implications for device design, and possible means of avoiding the formation of such a dead zone, are discussed.

  13. Target blood pressure in diabetes patients with hypertension--what is the accumulated evidence in 2011?

    PubMed

    Nilsson, Peter M

    2011-08-01

    There is overwhelming evidence that hypertension is an important risk factor for both macrovascular and microvascular complications in patients with diabetes, but the problem remains to identify appropriate goals for preventive therapies. A number of guidelines (the European Society of Cardiology (ESC)/European Association for the Study of Diabetes (EASD) 2007, the Joint National Committee (JNC)-VII 2003, the American Diabetes Association (ADA) 2011) have for example advocated a blood pressure goal of less than 130/80 mmHg, but this suggestion has been challenged by findings in recent trials and meta-analyses (2011). The European Society of Hypertension (ESH) therefore recommends a systolic blood pressure goal of "well below" 140 mmHg. Based on evidence from both randomized controlled trials (hypertension optimal treatment (HOT), action in diabetes and vascular disease: preterax and diamicron MR controlled evaluation (ADVANCE), action to control cardiovascular risk in diabetes (ACCORD)) and observational studies (ongoing telmisartan alone and in combination with ramipril global endpoint trial (ONTARGET), international verapamil-trandolapril study (INVEST), treat to new targets (TNT), and the National Diabetes Register (NDR)), it has been shown that the benefit for stroke reduction remains even at lower achieved blood pressure levels, but the risk of coronary events may be uninfluenced or even increased at lower systolic blood pressure levels. In a recent meta-analysis, it was therefore concluded that the new recommended goal should be 130-135 mmHg systolic blood pressure for most patients with type 2 diabetes. Other risk factors should also be controlled with a more ambitious strategy applied in the younger patients with shorter diabetes duration, but a more cautious approach in the elderly and frail patients with a number of vascular or non-vascular co-morbidities. In patients from East Asia, such as China, the stroke risk is relatively higher than the risk of

  14. Accumulating evidence supports a taste component for free fatty acids in humans.

    PubMed

    Mattes, Richard D

    2011-09-26

    The requisite criteria for what constitutes a taste primary have not been established. Recent advances in understanding of the mechanisms and functions of taste have prompted suggestions for an expanded list of unique taste sensations, including fat, or more specifically, free fatty acids (FFA). A set of criteria are proposed here and the data related to FFA are reviewed on each point. It is concluded that the data are moderate to strong that there are: A) adaptive advantages to FFA detection in the oral cavity; B) adequate concentrations of FFA to serve as taste stimuli; C) multiple complimentary putative FFA receptors on taste cells; D) signals generated by FFA that are conveyed by gustatory nerves; E) sensations generated by FFA that can be detected and scaled by psychophysical methods in humans when non-gustatory cues are masked; and F) physiological responses to oral fat/FFA exposure. On no point is there strong evidence challenging these observations. The reviewed findings are suggestive, albeit not definitive, that there is a taste component for FFA.

  15. Accumulating Evidence Supports a Taste Component for Free Fatty Acids in Humans

    PubMed Central

    Mattes, Richard D.

    2011-01-01

    The requisite criteria for what constitutes a taste primary have not been established. Recent advances in understanding of the mechanisms and functions of taste have prompted suggestions for an expanded list of unique taste sensations, including fat, or more specifically, free fatty acids (FFA). A set of criteria are proposed here and the data related to FFA are reviewed on each point. It is concluded that the data are moderate to strong that there are: A) adaptive advantages to FFA detection in the oral cavity; B) adequate concentrations of FFA to serve as taste stimuli; C) multiple complimentary putative FFA receptors on taste cells; D) signals generated by FFA that are conveyed by gustatory nerves; E) sensations generated by FFA that can be detected and scaled by psychophysical methods in humans when non-gustatory cues are masked; and F) physiological responses to oral fat/FFA exposure. On no point is there strong evidence challenging these observations. The reviewed findings are suggestive, albeit not definitive, that there is a taste component for FFA. PMID:21557960

  16. Quercetin Alleviates High-Fat Diet-Induced Oxidized Low-Density Lipoprotein Accumulation in the Liver: Implication for Autophagy Regulation.

    PubMed

    Liu, Liang; Gao, Chao; Yao, Ping; Gong, Zhiyong

    2015-01-01

    A growing body of evidence has indicated that high-fat diet-induced nonalcoholic fatty liver disease is usually accompanied by oxidized low-density lipoprotein (ox-LDL) deposited in the liver. The current study aimed to investigate the effect of quercetin on high-fat diet-induced ox-LDL accumulation in the liver and to explore the potential underlying mechanisms. The results demonstrate that quercetin supplementation for 24 weeks significantly alleviated high-fat diet-induced liver damage and reduced hepatic cholesterol and ox-LDL level. Quercetin notably inhibited both mRNA and protein expression of CD36 (reduced by 53% and 71%, resp.) and MSR1 (reduced by 25% and 45%, resp.), which were upregulated by high-fat diet. The expression of LC3II was upregulated by 2.4 times whereas that of p62 and mTOR was downregulated by 57% and 63% by quercetin treatment. Therefore, the significantly improved autophagy lysosomal degradation capacity for ox-LDL may be implicated in the hepatoprotective effect of quercetin; scavenger receptors mediated ox-LDL uptake might also be involved.

  17. Quercetin Alleviates High-Fat Diet-Induced Oxidized Low-Density Lipoprotein Accumulation in the Liver: Implication for Autophagy Regulation

    PubMed Central

    Liu, Liang; Gao, Chao; Yao, Ping; Gong, Zhiyong

    2015-01-01

    A growing body of evidence has indicated that high-fat diet-induced nonalcoholic fatty liver disease is usually accompanied by oxidized low-density lipoprotein (ox-LDL) deposited in the liver. The current study aimed to investigate the effect of quercetin on high-fat diet-induced ox-LDL accumulation in the liver and to explore the potential underlying mechanisms. The results demonstrate that quercetin supplementation for 24 weeks significantly alleviated high-fat diet-induced liver damage and reduced hepatic cholesterol and ox-LDL level. Quercetin notably inhibited both mRNA and protein expression of CD36 (reduced by 53% and 71%, resp.) and MSR1 (reduced by 25% and 45%, resp.), which were upregulated by high-fat diet. The expression of LC3II was upregulated by 2.4 times whereas that of p62 and mTOR was downregulated by 57% and 63% by quercetin treatment. Therefore, the significantly improved autophagy lysosomal degradation capacity for ox-LDL may be implicated in the hepatoprotective effect of quercetin; scavenger receptors mediated ox-LDL uptake might also be involved. PMID:26697490

  18. Disease-related malnutrition in systemic sclerosis: evidences and implications.

    PubMed

    Codullo, Veronica; Cereda, Emanuele; Crepaldi, Gloria; Cappello, Silvia; Montecucco, Carlomaurizio; Caccialanza, Riccardo; Caporali, Roberto

    2015-01-01

    The present review summarises evidences and provides recommendations for the screening and management of malnutrition in systemic sclerosis (SSc). This complication is frequently under-estimated when assessing patients and this may lead to an impaired estimation of prognosis. The presence of malnutrition is indicated by anthropometric and biohumoral changes reflecting protein stores (low serum prealbumin) and influenced by organ involvement in SSc (skin and the gastrointestinal tract). Patients at high risk of malnutrition or with low prealbumin levels have shown increased mortality risk and, therefore, a nutritional assessment is mandatory in every SSc patient. This screening is especially important as malnutrition represents a potentially modifiable risk factor with nutritional interventions. The pillars of nutritional treatment are also discussed.

  19. Paleozoic diamictites in the Peruvian Altiplano: evidence and tectonic implications

    NASA Astrophysics Data System (ADS)

    Díaz-Martínez, Enrique; Acosta, Harmuth; Cardenas, José; Carlotto, Víctor; Rodríguez, Rildo

    2001-11-01

    Striated and faceted clasts found within the diamictites of the San Gabán Formation immediately north of Ayaviri (southeast Peru) are interpreted as evidence for the late Ashgill-Llandovery glaciations in the Peruvian Altiplano, an area where this unit was previously considered not to be deposited. The Lower Paleozoic stratigraphic sequence cropping out in the area includes the Sandia, San Gabán, and Ananea Formations, and thus belongs to the Eastern Cordillera tectonostratigraphic domain, but within the Altiplano morphotectonic region. The marked difference between the Lower Paleozoic sequences of the Altiplano and Eastern Cordillera tectonostratigraphic domains suggests important tectonic shortening along the boundary fault zone during Andean Cenozoic deformation.

  20. Limitations of observational evidence: implications for evidence-based dietary recommendations.

    PubMed

    Maki, Kevin C; Slavin, Joanne L; Rains, Tia M; Kris-Etherton, Penny M

    2014-01-01

    Data from randomized controlled trials (RCTs) provide the strongest evidence for establishing relations between exposures, including dietary exposures, and health outcomes. However, not all diet and health outcome relations can be practically or ethically evaluated by using RCTs; therefore, many dietary recommendations are supported by evidence primarily from observational data, particularly those from prospective cohort studies. Although such evidence is of critical importance, limitations are often underappreciated by nutrition scientists and policymakers. This editorial review is intended to 1) highlight some of these limitations of observational evidence for diet-disease relations, including imprecise exposure quantification, collinearity among dietary exposures, displacement/substitution effects, healthy/unhealthy consumer bias, residual confounding, and effect modification; and 2) advocate for greater caution in the communication of dietary recommendations for which RCT evidence of clinical event reduction after dietary intervention is not available.

  1. Gas retention and accumulation in stellar clusters and galaxies: Implications for star formation and black hole accretion

    NASA Astrophysics Data System (ADS)

    Naiman, Jill

    Star formation cannot proceed without the existence of an extensive gas reservoir. In particular, the supply of gas to form stars in dwarf galaxies and star clusters requires overcoming a variety of difficulties - namely, the effectiveness of different feedback mechanisms in removing gas from these shallow gravitational potentials. In addition, the supply of external gas to these systems is determined by the large scale galactic structure in which they reside. This thesis employs computational hydrodynamics coupled with physically realistic subgrid feedback prescriptions to resolve the interplay between the small scale feedback mechanisms and larger scale gas flows to determine the amount of gas a shallow potential can accumulate. First, we consider the flow of gas external to dwarf galaxies and star clusters into their cores as a generalized accretion process. Second, we explore the enhancement of gas accretion rates onto the compact members of young star clusters when the flow of external gas into the cluster cores is large. Third, we discuss how external gas flows initiated by the presence of a massive nuclear star cluster can enhance central massive black hole accretion rates during galaxy mergers. Fourth, we change our focus to exploring internal stellar wind retention in proto-globular clusters as a mechanism to supply gas for multiple episodes of star formation. Finally, the implications of stellar wind retention on the current gas reservoir in globular clusters is discussed.

  2. [Etiologic implication of foods in atopic dermatitis: evidence in favor].

    PubMed

    Fernández-Benítez, M

    2002-01-01

    Some of the immunopathologic mechanisms involved in IgE responses are currently being identified; Th2 lymphocytes are known to be activated in patients with atopic dermatitis with subsequent production of the cytokines interleukin (IL)-4 and IL-5, which are responsible for IgE production and eosinophil recruitment. Nevertheless, T cell activation in this disease takes place in two phases. In the first phase, Th2 cells are activated and IL-4, IL-5 and IL-13 are produced; this first stage is produced with the initial activation induced by the antigen. In the second phase there are chronic lesions, Th1 lymphocytes are activated and IFg is produced. This chronic phase is associated with the presence of eosinophils and macrophages that produce IL-12.Numerous articles have demonstrated food sensitization to be an etiopathogenic factor in atopic dermatitis. The prevalence of sensitization varies, depending on the patient's age and the severity of the disease. Children with moderate-to-severe atopic dermatitis have been observed to have a positive skin test and high IgE concentrations to various foods. Nevertheless, a positive skin test to foods in such children does not always implicate these foods as the cause of the clinical manifestations; moreover, in children showing subsequent tolerance to these foods, skin tests can sometimes remain positive and high levels of specific IgE can persist. It is now known that IgE not only participate in the degranulation of mastocyte cells but also in reactions mediated by T cells and other antigen-presenting cells (dendritic cells) which have high-affinity receptors for IgE.The immediate IgE response is well known but it is also known that in addition to the immediate response, a delayed response is also involved, evidenced by the presence of antigen-specific T cells to foods or other allergens such as inhalant allergens. After a strict exclusion diet, children with atopic dermatitis and sensitivity to foods such as milk, egg, flour

  3. Anticholinergic medication use and dementia: latest evidence and clinical implications

    PubMed Central

    Gray, Shelly L.; Hanlon, Joseph T.

    2016-01-01

    Use of medications with anticholinergic activity is widespread in older adults. Several studies have highlighted that anticholinergic use may be associated with an increased risk of dementia. The objective of this narrative review is to describe and evaluate studies of anticholinergic medication use and dementia and provide practical suggestions for avoiding use of these medications in older adults. A comprehensive review of the literature, citations from recent reviews and the author’s personal files was conducted. Four studies were found that evaluated anticholinergic use and dementia as the primary outcome. Three studies focused on overall anticholinergic medication use and reported a statistically significantly increased risk of Alzheimer’s disease or dementia. In one study, dementia risk was primarily found with higher cumulative doses; people using anticholinergic medications at the minimum effective dose recommended for older adults for at least 3 years were at highest risk. In contrast, a study conducted in nursing-home residents with depression did not find that paroxetine [a highly anticholinergic selective serotonin reuptake inhibitor antidepressant, (SSRI)] increased risk for dementia compared with other SSRIs (without anticholinergic activity). Further study is needed to understand the mechanism by which anticholinergic medications may increase risk. In conclusion, there is evidence from three observational studies suggesting that anticholinergic medications may increase dementia risk. Given this potential risk and the myriad of other well-known adverse effects (i.e. constipation, blurred vision, urinary retention, and delirium) associated with anticholinergic medications, it is prudent for prescribers and older adults to minimize use of these medications and consider alternatives when possible. PMID:27695623

  4. Fetal Implications of Diagnostic Radiation Exposure During Pregnancy: Evidence-based Recommendations.

    PubMed

    Rimawi, Bassam H; Green, Victoria; Lindsay, Michael

    2016-06-01

    The purpose of this article is to review the fetal and long-term implications of diagnostic radiation exposure during pregnancy. Evidence-based recommendations for radiologic imaging modalities utilizing exposure of diagnostic radiation during pregnancy, including conventional screen-film mammography, digital mammography, tomosynthesis, and contrast-enhanced mammography are described. PMID:26982251

  5. Keeping agricultural soil out of rivers: evidence of sediment and nutrient accumulation within field wetlands in the UK.

    PubMed

    Ockenden, Mary C; Deasy, Clare; Quinton, John N; Surridge, Ben; Stoate, Chris

    2014-03-15

    Intensification of agriculture has resulted in increased soil degradation and erosion, with associated pollution of surface waters. Small field wetlands, constructed along runoff pathways, offer one option for slowing down and storing runoff in order to allow more time for sedimentation and for nutrients to be taken up by plants or micro-organisms. This paper describes research to provide quantitative evidence for the effectiveness of small field wetlands in the UK landscape. Ten wetlands were built on four farms in Cumbria and Leicestershire, UK. Annual surveys of sediment and nutrient accumulation in 2010, 2011 and 2012 indicated that most sediment was trapped at a sandy site (70 tonnes over 3 years), compared to a silty site (40 tonnes over 3 years) and a clay site (2 tonnes over 3 years). The timing of rainfall was more important than total annual rainfall for sediment accumulation, with most sediment transported in a few intense rainfall events, especially when these coincided with bare soil or poor crop cover. Nutrient concentration within sediments was inversely related to median particle size, but the total mass of nutrients trapped was dependent on the total mass of sediment trapped. Ratios of nutrient elements in the wetland sediments were consistent between sites, despite different catchment characteristics across the individual wetlands. The nutrient value of sediment collected from the wetlands was similar to that of soil in the surrounding fields; dredged sediment was considered to have value as soil replacement but not as fertiliser. Overall, small field wetlands can make a valuable contribution to keeping soil out of rivers.

  6. Keeping agricultural soil out of rivers: evidence of sediment and nutrient accumulation within field wetlands in the UK.

    PubMed

    Ockenden, Mary C; Deasy, Clare; Quinton, John N; Surridge, Ben; Stoate, Chris

    2014-03-15

    Intensification of agriculture has resulted in increased soil degradation and erosion, with associated pollution of surface waters. Small field wetlands, constructed along runoff pathways, offer one option for slowing down and storing runoff in order to allow more time for sedimentation and for nutrients to be taken up by plants or micro-organisms. This paper describes research to provide quantitative evidence for the effectiveness of small field wetlands in the UK landscape. Ten wetlands were built on four farms in Cumbria and Leicestershire, UK. Annual surveys of sediment and nutrient accumulation in 2010, 2011 and 2012 indicated that most sediment was trapped at a sandy site (70 tonnes over 3 years), compared to a silty site (40 tonnes over 3 years) and a clay site (2 tonnes over 3 years). The timing of rainfall was more important than total annual rainfall for sediment accumulation, with most sediment transported in a few intense rainfall events, especially when these coincided with bare soil or poor crop cover. Nutrient concentration within sediments was inversely related to median particle size, but the total mass of nutrients trapped was dependent on the total mass of sediment trapped. Ratios of nutrient elements in the wetland sediments were consistent between sites, despite different catchment characteristics across the individual wetlands. The nutrient value of sediment collected from the wetlands was similar to that of soil in the surrounding fields; dredged sediment was considered to have value as soil replacement but not as fertiliser. Overall, small field wetlands can make a valuable contribution to keeping soil out of rivers. PMID:24509365

  7. Brain iron accumulation affects myelin-related molecular systems implicated in a rare neurogenetic disease family with neuropsychiatric features

    PubMed Central

    Heidari, M; Johnstone, D M; Bassett, B; Graham, R M; Chua, A C G; House, M J; Collingwood, J F; Bettencourt, C; Houlden, H; Ryten, M; Olynyk, J K; Trinder, D; Milward, E A

    2016-01-01

    The ‘neurodegeneration with brain iron accumulation' (NBIA) disease family entails movement or cognitive impairment, often with psychiatric features. To understand how iron loading affects the brain, we studied mice with disruption of two iron regulatory genes, hemochromatosis (Hfe) and transferrin receptor 2 (Tfr2). Inductively coupled plasma atomic emission spectroscopy demonstrated increased iron in the Hfe−/− × Tfr2mut brain (P=0.002, n ≥5/group), primarily localized by Perls' staining to myelinated structures. Western immunoblotting showed increases of the iron storage protein ferritin light polypeptide and microarray and real-time reverse transcription-PCR revealed decreased transcript levels (P<0.04, n ≥5/group) for five other NBIA genes, phospholipase A2 group VI, fatty acid 2-hydroxylase, ceruloplasmin, chromosome 19 open reading frame 12 and ATPase type 13A2. Apart from the ferroxidase ceruloplasmin, all are involved in myelin homeostasis; 16 other myelin-related genes also showed reduced expression (P<0.05), although gross myelin structure and integrity appear unaffected (P>0.05). Overlap (P<0.0001) of differentially expressed genes in Hfe−/− × Tfr2mut brain with human gene co-expression networks suggests iron loading influences expression of NBIA-related and myelin-related genes co-expressed in normal human basal ganglia. There was overlap (P<0.0001) of genes differentially expressed in Hfe−/− × Tfr2mut brain and post-mortem NBIA basal ganglia. Hfe−/− × Tfr2mut mice were hyperactive (P<0.0112) without apparent cognitive impairment by IntelliCage testing (P>0.05). These results implicate myelin-related systems involved in NBIA neuropathogenesis in early responses to iron loading. This may contribute to behavioral symptoms in NBIA and hemochromatosis and is relevant to patients with abnormal iron status and psychiatric disorders involving myelin abnormalities or resistant to conventional treatments. PMID:26728570

  8. The Physics of Decision Making:. Stochastic Differential Equations as Models for Neural Dynamics and Evidence Accumulation in Cortical Circuits

    NASA Astrophysics Data System (ADS)

    Holmes, Philip; Eckhoff, Philip; Wong-Lin, K. F.; Bogacz, Rafal; Zacksenhouse, Miriam; Cohen, Jonathan D.

    2010-03-01

    We describe how drift-diffusion (DD) processes - systems familiar in physics - can be used to model evidence accumulation and decision-making in two-alternative, forced choice tasks. We sketch the derivation of these stochastic differential equations from biophysically-detailed models of spiking neurons. DD processes are also continuum limits of the sequential probability ratio test and are therefore optimal in the sense that they deliver decisions of specified accuracy in the shortest possible time. This leaves open the critical balance of accuracy and speed. Using the DD model, we derive a speed-accuracy tradeoff that optimizes reward rate for a simple perceptual decision task, compare human performance with this benchmark, and discuss possible reasons for prevalent sub-optimality, focussing on the question of uncertain estimates of key parameters. We present an alternative theory of robust decisions that allows for uncertainty, and show that its predictions provide better fits to experimental data than a more prevalent account that emphasises a commitment to accuracy. The article illustrates how mathematical models can illuminate the neural basis of cognitive processes.

  9. Activity in Inferior Parietal and Medial Prefrontal Cortex Signals the Accumulation of Evidence in a Probability Learning Task

    PubMed Central

    d'Acremont, Mathieu; Fornari, Eleonora; Bossaerts, Peter

    2013-01-01

    In an uncertain environment, probabilities are key to predicting future events and making adaptive choices. However, little is known about how humans learn such probabilities and where and how they are encoded in the brain, especially when they concern more than two outcomes. During functional magnetic resonance imaging (fMRI), young adults learned the probabilities of uncertain stimuli through repetitive sampling. Stimuli represented payoffs and participants had to predict their occurrence to maximize their earnings. Choices indicated loss and risk aversion but unbiased estimation of probabilities. BOLD response in medial prefrontal cortex and angular gyri increased linearly with the probability of the currently observed stimulus, untainted by its value. Connectivity analyses during rest and task revealed that these regions belonged to the default mode network. The activation of past outcomes in memory is evoked as a possible mechanism to explain the engagement of the default mode network in probability learning. A BOLD response relating to value was detected only at decision time, mainly in striatum. It is concluded that activity in inferior parietal and medial prefrontal cortex reflects the amount of evidence accumulated in favor of competing and uncertain outcomes. PMID:23401673

  10. Road Salt Accumulation and Wash-out in Stormwater Detention Basins: Patterns and Implications for Biogeochemical Cycling

    NASA Astrophysics Data System (ADS)

    McPhillips, L. E.; Walter, M. T.

    2014-12-01

    There is increasing evidence that salt application to roads and parking lots in winter is driving a rise in chloride concentrations in streams in the northeastern United States. Our research focuses specifically on salt dynamics in stormwater detention basins, which receive runoff directly from parking lots and detain it before it reaches the stream. The four study basins are located on the Cornell University campus in Ithaca, NY USA. Between summer 2012 and 2014, soil electrical conductivity was continuously monitored inside and outside the basins using Decagon 5TE sensors and dataloggers. In two basins which drain stormwater quickly, conductivity levels changed minimally over the year. However, in the other two basins which drain much slower and often are saturated, conductivity increased through the winter, peaking at 8-10 mS/cm, and then took several months to decrease to baseline levels; thus the basins served as a source of salt to outflowing water even into the summer. This annual variation in soil salinity has implications for plant and microbial communities living in these basins. Research by colleagues has indicated that changing salinity can alter microbial communities and impact biogeochemical processes that play a role in water quality remediation. Thus we are also investigating the impact of salinity on denitrification rates in these basins. All of this information will help us understand what role stormwater detention basins are playing in controlling fluxes of road salt in watersheds, as well as how changing salinity influences the ecosystem services provided by these basins.

  11. Synchrotron FTIR shows evidence of DNA damage and lipid accumulation in prostate adenocarcinoma PC-3 cells following proton irradiation

    NASA Astrophysics Data System (ADS)

    Lipiec, Ewelina; Bambery, Keith R.; Heraud, Phil; Hirschmugl, Carol; Lekki, Janusz; Kwiatek, Wojciech M.; Tobin, Mark J.; Vogel, Christian; Whelan, Donna; Wood, Bayden R.

    2014-09-01

    Synchrotron Radiation Fourier Transform Infrared (SR-FTIR) spectra of single human prostate adenocarcinoma PC-3 cells, irradiated with a defined number of 2 MeV protons generated by a proton microbeam along with non-irradiated control cells, were analysed using multivariate methods. A number of different Principal Component Analysis (PCA) models were tested and the spectral ranges associated with nucleic acids, proteins and lipids were analysed separately. The results show a dose dependent shift of the Osbnd Psbnd O asymmetric stretching mode from 1234 cm-1 to 1237 cm-1, consistent with local disorder in the B-DNA conformation along with a change in intensity of the Osbnd Psbnd O symmetric stretching band at 1083 cm-1 indicative of chromatin fragmentation - the natural consequence of a high number of DNA Double Strand Breaks (DSBs). 2D mapping of characteristic functional groups at the diffraction limit shows evidence of lipid deposition and chromatin condensation in cells exposed to protons indicative of cell apoptosis following irradiation. These studies lay the foundation for understanding the macromolecular changes that occur to cells in response to radiation therapy, which has important implications in the treatment of tumours.

  12. The relation between Acid Volatile Sulfides (AVS) and metal accumulation in aquatic invertebrates: implications of feeding behavior and ecology.

    PubMed

    De Jonge, Maarten; Blust, Ronny; Bervoets, Lieven

    2010-05-01

    The present study evaluates the relationship between Acid Volatile Sulfides (AVS) and metal accumulation in invertebrates with different feeding behavior and ecological preferences. Natural sediments, pore water and surface water, together with benthic and epibenthic invertebrates were sampled at 28 Flemish lowland rivers. Different metals as well as metal binding sediment characteristics including AVS were measured and multiple regression was used to study their relationship with accumulated metals in the invertebrates taxa. Bioaccumulation in the benthic taxa was primarily influenced by total metal concentrations in the sediment. Regarding the epibenthic taxa metal accumulation was mostly explained by the more bioavailable metal fractions in both the sediment and the water. AVS concentrations were generally better correlated with metal accumulation in the epibenthic invertebrates, rather than with the benthic taxa. Our results indicated that the relation between AVS and metal accumulation in aquatic invertebrates is highly dependent on feeding behavior and ecology.

  13. A record of Late Pleistocene and Holocene carbon accumulation and climate change from an equatorial peat bog (Kalimantan, Indonesia): implications for past, present and future carbon dynamics

    NASA Astrophysics Data System (ADS)

    Page, S. E.; Wst, R. A. J.; Weiss, D.; Rieley, J. O.; Shotyk, W.; Limin, S. H.

    2004-10-01

    A 9.5 m core from an inland peatland in Kalimantan, Indonesia, reveals organic matter accumulation started around 26 000 cal. yr BP, providing the oldest reported initiation date for lowland ombrotrophic peat formation in SE Asia. The core shows clear evidence for differential rates of peat formation and carbon storage. A short period of initial accumulation is followed by a slow rate during the LGM, with fastest accumulation during the Holocene. Between 13 000 and 8000 cal. yr BP, > 450 cm of peat were deposited, with highest rates of peat (> 2 mm yr-1) and carbon (> 90 g C m-2yr-1) accumulation between 9530 and 8590cal.yrBP. These data suggest that Kalimantan peatlands acted as a large sink of atmospheric CO2 at this time. Slower rates of peat (0.15-0.38mmyr-1) and carbon (7.4-24.0gCm-2yr-1) accumulation between 8000 and 500cal.yrBP coincide with rapid peat formation in coastal locations elsewhere in SE Asia. The average LORCA (long-term apparent carbon accumulation rate) for the 9.5m core is 56gCm-2yr-1. These data suggest that studies of global carbon sources, sinks and their dynamics need to include information on the past and present sizeable peat deposits of the tropics. Copyright

  14. Implications of Bishop Tuff zircon U-Pb ages for rates of zircon growth and magma accumulation

    NASA Astrophysics Data System (ADS)

    Reid, M. R.; Schmitt, A. K.

    2012-12-01

    Rates of geologic processes obtained from natural studies rely on accurate geochronologic information. An important benchmark in geochronology as well as a valuable source of insights into the evolution of voluminous explosive eruptions is the >600 km3 Bishop Tuff (BT). A recently determined weighted mean 206Pb/238U date of 767.1±0.9 ka for a BT zircon population [1] is indistinguishable from the recalibrated 40Ar/39Ar sanidine date of 767.4±2.2 ka [2], potentially providing a key intercalibration point between astronomical and radio-isotopic dating approaches. Consequences of these results are linear zircon growth rates of >1×10-14 cm/sec and magma accumulation rates of >200 km3/ka. In contrast, spatially selective SIMS U-Pb dating of BT zircons yielded mean pre-eruption ages of 850 ka [3], a difference that raises questions about the validity of intercalibration between U-Pb and K-Ar dating methods and the history of magma accumulation. We obtained new SIMS analyses of the BT zircons using more spatially and analytically sensitive methods and verifying our accuracy against the TIMS dated Quaternary zircon 61.308A (2.488±0.002 Ma). Analyses were performed on zircon rims and on oriented cross-sections exposed during optical interferometry-calibrated serial sectioning removing the outermost ~31 μm. Sputtering by a 100 nA ion beam versus the normally employed 10-12 nA beam resulted in enhanced radiogenic Pb yields and analytical uncertainties for Quaternary zircon approaching the U-Pb age reproducibility of the primary zircon standard (~1-2 % for AS3). Ages obtained at ~31 μm depth (representing <5% of crystal growth in most cases) average 892±26ka (MSWD=0.29), corroborating previous evidence for residence times of several tens of ka. Rim ages average 781±22 ka (MSWD=0.61), overlapping Ar/Ar determinations of eruption age and corroborating the importance of near-eruption aged zircon growth. Our results confirm the presence of BT zircon domains that predate

  15. Intraspecific variation in cadmium tolerance and accumulation of a high-biomass tropical tree Averrhoa carambola L.: implication for phytoextraction.

    PubMed

    Dai, Zi-yun; Shu, Wen-sheng; Liao, Bin; Wan, Cai-yun; Li, Jin-tian

    2011-06-01

    Averrhoa carambola L., a high-biomass tropical tree, has recently been shown to be a strong accumulator of cadmium (Cd) and has great potential for Cd phytoextraction. In the present study, field studies and a controlled-environment experiment were combined to establish the extent of variation in Cd tolerance and accumulation at the cultivar level using 14 to 19 cultivars of A. carambola. The results indicated that all cultivars tested could accumulate Cd at high but different levels, and that Cd tolerance also varied greatly between these cultivars. It is confirmed that the high Cd tolerance and accumulation capacity are species-level and constitutional traits in A. carambola. However, no correlation was detected between tolerance index and accumulation of Cd in different cultivars, suggesting that the two traits are independent in this woody Cd accumulator. More importantly, cultivar Wuchuan Sweet (WCT) was shown to have the highest Cd-extraction potential; it yielded a high shoot biomass of 30 t ha(-1) in 230 d, and extracted 330 g ha(-1) Cd in the aerial tissues grown in Cd-contaminated field soil, which accounted for 12.8% of the total soil Cd in the top 20 cm of the soil profile.

  16. A survey of mangiferin and hydroxycinnamic acid ester accumulation in coffee (Coffea) leaves: biological implications and uses

    PubMed Central

    Campa, Claudine; Mondolot, Laurence; Rakotondravao, Arsene; Bidel, Luc P. R.; Gargadennec, Annick; Couturon, Emmanuel; La Fisca, Philippe; Rakotomalala, Jean-Jacques; Jay-Allemand, Christian; Davis, Aaron P.

    2012-01-01

    Background and Aims The phenolic composition of Coffea leaves has barely been studied, and therefore this study conducts the first detailed survey, focusing on mangiferin and hydroxycinnamic acid esters (HCEs). Methods Using HPLC, including a new technique allowing quantification of feruloylquinic acid together with mangiferin, and histochemical methods, mangiferin content and tissue localization were compared in leaves and fruits of C. pseudozanguebariae, C. arabica and C. canephora. The HCE and mangiferin content of leaves was evaluated for 23 species native to Africa or Madagascar. Using various statistical methods, data were assessed in relation to distribution, ecology, phylogeny and use. Key Results Seven of the 23 species accumulated mangiferin in their leaves. Mangiferin leaf-accumulating species also contain mangiferin in the fruits, but only in the outer (sporophytic) parts. In both leaves and fruit, mangiferin accumulation decreases with ageing. A relationship between mangiferin accumulation and UV levels is posited, owing to localization with photosynthetic tissues, and systematic distribution in high altitude clades and species with high altitude representatives. Analyses of mangiferin and HCE content showed that there are significant differences between species, and that samples can be grouped into species, with few exceptions. These data also provide independent support for various Coffea lineages, as proposed by molecular phylogenetic analyses. Sampling of the hybrids C. arabica and C. heterocalyx cf. indicates that mangiferin and HCE accumulation may be under independent parental influence. Conclusions This survey of the phenolic composition in Coffea leaves shows that mangiferin and HCE accumulation corresponds to lineage recognition and species delimitation, respectively. Knowledge of the spectrum of phenolic accumulation within species and populations could be of considerable significance for adaptation to specific environments. The potential

  17. The Case for Conscientiousness: Evidence and Implications for a Personality Trait Marker of Health and Longevity

    PubMed Central

    Bogg, Tim; Roberts, Brent W.

    2012-01-01

    Purpose Recent initiatives by major funding agencies have emphasized translational and personalized approaches (e.g., genetic testing) to health research and health management. While such directives are appropriate, and will likely produce tangible health benefits, we seek to highlight a confluence of several lines of research showing relations between the personality dimension of conscientiousness and a variety of health-related outcomes. Methods Using a modified health process model, we review the compelling evidence linking conscientiousness to health and disease processes, including longevity, diseases, morbidity-related risk factors, health-related psycho-physiological mechanisms, health-related behaviors, and social environmental factors related to health. Conclusion We argue the accumulated evidence supports greater integration of conscientiousness into public health, epidemiological, and medical research, with the ultimate aim of understanding how facilitating more optimal trait standing might foster better health. PMID:23225322

  18. Molecular chaperone accumulation as a function of stress evidences adaptation to high hydrostatic pressure in the piezophilic archaeon Thermococcus barophilus

    PubMed Central

    Cario, Anaïs; Jebbar, Mohamed; Thiel, Axel; Kervarec, Nelly; Oger, Phil M.

    2016-01-01

    The accumulation of mannosyl-glycerate (MG), the salinity stress response osmolyte of Thermococcales, was investigated as a function of hydrostatic pressure in Thermococcus barophilus strain MP, a hyperthermophilic, piezophilic archaeon isolated from the Snake Pit site (MAR), which grows optimally at 40 MPa. Strain MP accumulated MG primarily in response to salinity stress, but in contrast to other Thermococcales, MG was also accumulated in response to thermal stress. MG accumulation peaked for combined stresses. The accumulation of MG was drastically increased under sub-optimal hydrostatic pressure conditions, demonstrating that low pressure is perceived as a stress in this piezophile, and that the proteome of T. barophilus is low-pressure sensitive. MG accumulation was strongly reduced under supra-optimal pressure conditions clearly demonstrating the structural adaptation of this proteome to high hydrostatic pressure. The lack of MG synthesis only slightly altered the growth characteristics of two different MG synthesis deletion mutants. No shift to other osmolytes was observed. Altogether our observations suggest that the salinity stress response in T. barophilus is not essential and may be under negative selective pressure, similarly to what has been observed for its thermal stress response. PMID:27378270

  19. Implication of citrate, malate and histidine in the accumulation and transport of nickel in Mesembryanthemum crystallinum and Brassica juncea.

    PubMed

    Amari, Taoufik; Lutts, Stanley; Taamali, Manel; Lucchini, Giorgio; Sacchi, Gian Attilio; Abdelly, Chedly; Ghnaya, Tahar

    2016-04-01

    Citrate, malate and histidine have been involved in many processes including metal tolerance and accumulation in plants. These molecules have been frequently reported to be the potential nickel chelators, which most likely facilitate metal transport through xylem. In this context, we assess here, the relationship between organics acids and histidine content and nickel accumulation in Mesembryanthemum crystallinum and Brassica juncea grown in hydroponic media added with 25, 50 and 100 µM NiCl2. Results showed that M. crystallinum is relatively more tolerant to Ni toxicity than B. juncea. For both species, xylem transport rate of Ni increased with increasing Ni supply. A positive correlation was established between nickel and citrate concentrations in the xylem sap. In the shoot of B. juncea, citric and malic acids concentrations were significantly higher than in the shoot of M. crystallinum. Also, the shoots and roots of B. juncea accumulated much more histidine. In contrast, a higher root citrate concentration was observed in M. crystallinum. These findings suggest a specific involvement of malic and citric acid in Ni translocation and accumulation in M. crystallinum and B. juncea. The high citrate and histidine accumulation especially at 100µM NiCl2, in the roots of M. crystallinum might be among the important factors associated with the tolerance of this halophyte to toxic Ni levels.

  20. Implication of citrate, malate and histidine in the accumulation and transport of nickel in Mesembryanthemum crystallinum and Brassica juncea.

    PubMed

    Amari, Taoufik; Lutts, Stanley; Taamali, Manel; Lucchini, Giorgio; Sacchi, Gian Attilio; Abdelly, Chedly; Ghnaya, Tahar

    2016-04-01

    Citrate, malate and histidine have been involved in many processes including metal tolerance and accumulation in plants. These molecules have been frequently reported to be the potential nickel chelators, which most likely facilitate metal transport through xylem. In this context, we assess here, the relationship between organics acids and histidine content and nickel accumulation in Mesembryanthemum crystallinum and Brassica juncea grown in hydroponic media added with 25, 50 and 100 µM NiCl2. Results showed that M. crystallinum is relatively more tolerant to Ni toxicity than B. juncea. For both species, xylem transport rate of Ni increased with increasing Ni supply. A positive correlation was established between nickel and citrate concentrations in the xylem sap. In the shoot of B. juncea, citric and malic acids concentrations were significantly higher than in the shoot of M. crystallinum. Also, the shoots and roots of B. juncea accumulated much more histidine. In contrast, a higher root citrate concentration was observed in M. crystallinum. These findings suggest a specific involvement of malic and citric acid in Ni translocation and accumulation in M. crystallinum and B. juncea. The high citrate and histidine accumulation especially at 100µM NiCl2, in the roots of M. crystallinum might be among the important factors associated with the tolerance of this halophyte to toxic Ni levels. PMID:26745003

  1. An Interdependent Model of Central/Peripheral Chemoreception: Evidence and Implications for Ventilatory Control

    PubMed Central

    Smith, Curtis A.; Forster, Hubert V.; Blain, Grégory M.; Dempsey, Jerome A.

    2010-01-01

    In this review we discuss the implications for ventilatory control of newer evidence suggesting that central and peripheral chemoreceptors are not functionally separate but rather that they are dependent upon one another such that the sensitivity of the medullary chemoreceptors is critically determined by input from the carotid body chemoreceptors and vice versa i.e., they are interdependent. We examine potential interactions of the interdependent central and carotid body (CB) chemoreceptors with other ventilatory-related inputs such as central hypoxia, lung stretch, and exercise. The limitations of current approaches addressing this question are discussed and future studies are suggested. PMID:20206717

  2. Taphonomic and zooarchaeological implications of spotted hyena (crocuta crocuta) bone accumulations in kenya: A modern behavioral ecological approach

    USGS Publications Warehouse

    Lansing, S.W.; Cooper, S.M.; Boydston, E.E.; Holekamp, K.E.

    2009-01-01

    The significant impact of extant carnivores, particularly spotted hyenas, on the depo-sitional history and physical characteristics of archaeofaunal and paleontological assemblages is well recognized. We focus on the behavioral ecology of extant spotted hyenas (Crocuta crocuta) in relation to bone accumulations produced by one East African clan at communal dens. Limbs and skulls of prey animals more frequently appear at dens than do other carcass portions. These items reflect the relative abundance of prey species near dens; carnivore remains are poorly represented. Comparative analysis reveals that bones are deposited far more slowly (<7 carcass portions per month) and accumulations tend to be smaller at Crocuta dens than at dens of either brown (Para-hyaena brunnea) or striped (Hyaena hyaena) hyenas. We propose that extant Crocuta bone accumu-lation rates and sizes are likely affected by prey species abundance, clan size, social interactions within the clan, and the type and availability of den sites. We also suggest that the potential for intraspecific behavioral variability in bone accumulation patterns is important when comparisons are made among spotted hyena populations and across hyena species. For example, accumulation patterns may be dramatically influenced by the temporal span, potentially ranging from days to hundreds or thousands of years, in which bones are collected, depending on the species-specific history of occupation at a given site. Understanding the behavioral and ecological variability likely to influence bone accumulation patterns at dens used by different hyaenids will allow taphonomists and zooarchaeologists to refine their knowledge of mechanisms underlying site formation pro-cesses and potential causes of variability in deeper-time den assemblages. ?? 2009 The Paleontological Society.

  3. A Childbirth Educator's Commentary on Hormonal Physiology of Childbearing: Evidence and Implications for Women, Babies, and Maternity Care.

    PubMed

    Amis, Debby

    2015-01-01

    Sarah Buckley's game-changing report, Hormonal Physiology of Childbearing: Evidence and Implications for Women, Babies, and Maternity Care, provides the evidence that supporting, promoting, and protecting the normal physiology of childbirth produces the best outcomes for mothers and babies. In this article, a childbirth educator recommends key points from Buckley's report that should be included in Lamaze childbirth education classes. PMID:26834436

  4. Evidence for accumulation of Synechococcus elongatus (Cyanobacteria: Cyanophyceae) in the tissues of the oyster Crassostrea gigas (Mollusca: Bivalvia).

    PubMed

    Avila-Poveda, Omar Hernando; Torres-Ariño, Alejandra; Girón-Cruz, Diego Ademir; Cuevas-Aguirre, Angel

    2014-10-01

    Cyanobacteria appear to have direct relations with mollusks in several aspects. This is the first time, distinguishing Gram-negative cyanoprokaryotic Synechococcus elongatus as bright yellow-gold autofluorescence by Lillie's and Hiss' staining methods on paraffin-embedded tissues of Crassostrea gigas. Three diets: cyanoprokaryotes, cyanoprokaryotes with microalgae, and only microalgae were evaluated. Cyanoprokaryotes were intact, densely bundled, and immersed in the cytosol of the digestive gland, connective tissue, mantle, and gonad of C. gigas, revealing an accumulation systemic without tissue damage observed by histology. Unexpectedly, cyanoprokaryotes were slightly most accumulated with microalgae diet by each of the tissues of the C. gigas than with any other diets. Cyanoprokaryotes tend to be in mean slightly higher in the digestive gland than in any other tissues respectively for each diet, although these values are closely similar to connective tissue. A possible order of exposure of the oyster tissues to accumulation of cyanoprokaryotes was digestive gland, connective tissue, mantle, and gonad. Thereby, the digestive gland could be the major target tissue for the accumulation. Our observations provide a valuable insight regarding the ability of cyanoprokaryotes to penetrate, spread, and remain inside the oyster tissues, suggesting for S. elongatus: (1) a pre-accumulation in oyster tissues from the natural environment, (2) a phagocytosis and/or endocytosis process rather than ingestion and extracellular digestion, (3) an apparent cellular division in the cytosol of oyster tissues, (4) an apparent inter-tissue movement, and (5) a possible endosymbiosis between C. gigas and S. elongatus. Hereby, it is possible that S. elongatus have a well-developed host-endobiont relationship with oysters, and thereby support future work toward a description of the escape and spreading mechanisms of S. elongatus inside the tissues of mollusks, and put forward questions as

  5. Evidence for accumulation of Synechococcus elongatus (Cyanobacteria: Cyanophyceae) in the tissues of the oyster Crassostrea gigas (Mollusca: Bivalvia).

    PubMed

    Avila-Poveda, Omar Hernando; Torres-Ariño, Alejandra; Girón-Cruz, Diego Ademir; Cuevas-Aguirre, Angel

    2014-10-01

    Cyanobacteria appear to have direct relations with mollusks in several aspects. This is the first time, distinguishing Gram-negative cyanoprokaryotic Synechococcus elongatus as bright yellow-gold autofluorescence by Lillie's and Hiss' staining methods on paraffin-embedded tissues of Crassostrea gigas. Three diets: cyanoprokaryotes, cyanoprokaryotes with microalgae, and only microalgae were evaluated. Cyanoprokaryotes were intact, densely bundled, and immersed in the cytosol of the digestive gland, connective tissue, mantle, and gonad of C. gigas, revealing an accumulation systemic without tissue damage observed by histology. Unexpectedly, cyanoprokaryotes were slightly most accumulated with microalgae diet by each of the tissues of the C. gigas than with any other diets. Cyanoprokaryotes tend to be in mean slightly higher in the digestive gland than in any other tissues respectively for each diet, although these values are closely similar to connective tissue. A possible order of exposure of the oyster tissues to accumulation of cyanoprokaryotes was digestive gland, connective tissue, mantle, and gonad. Thereby, the digestive gland could be the major target tissue for the accumulation. Our observations provide a valuable insight regarding the ability of cyanoprokaryotes to penetrate, spread, and remain inside the oyster tissues, suggesting for S. elongatus: (1) a pre-accumulation in oyster tissues from the natural environment, (2) a phagocytosis and/or endocytosis process rather than ingestion and extracellular digestion, (3) an apparent cellular division in the cytosol of oyster tissues, (4) an apparent inter-tissue movement, and (5) a possible endosymbiosis between C. gigas and S. elongatus. Hereby, it is possible that S. elongatus have a well-developed host-endobiont relationship with oysters, and thereby support future work toward a description of the escape and spreading mechanisms of S. elongatus inside the tissues of mollusks, and put forward questions as

  6. Accumulate repeat accumulate codes

    NASA Technical Reports Server (NTRS)

    Abbasfar, Aliazam; Divsalar, Dariush; Yao, Kung

    2004-01-01

    In this paper we propose an innovative channel coding scheme called 'Accumulate Repeat Accumulate codes' (ARA). This class of codes can be viewed as serial turbo-like codes, or as a subclass of Low Density Parity Check (LDPC) codes, thus belief propagation can be used for iterative decoding of ARA codes on a graph. The structure of encoder for this class can be viewed as precoded Repeat Accumulate (RA) code or as precoded Irregular Repeat Accumulate (IRA) code, where simply an accumulator is chosen as a precoder. Thus ARA codes have simple, and very fast encoder structure when they representing LDPC codes. Based on density evolution for LDPC codes through some examples for ARA codes, we show that for maximum variable node degree 5 a minimum bit SNR as low as 0.08 dB from channel capacity for rate 1/2 can be achieved as the block size goes to infinity. Thus based on fixed low maximum variable node degree, its threshold outperforms not only the RA and IRA codes but also the best known LDPC codes with the dame maximum node degree. Furthermore by puncturing the accumulators any desired high rate codes close to code rate 1 can be obtained with thresholds that stay close to the channel capacity thresholds uniformly. Iterative decoding simulation results are provided. The ARA codes also have projected graph or protograph representation that allows for high speed decoder implementation.

  7. Genetic Factors Involved in Fumonisin Accumulation in Maize Kernels and Their Implications in Maize Agronomic Management and Breeding.

    PubMed

    Santiago, Rogelio; Cao, Ana; Butrón, Ana

    2015-08-20

    Contamination of maize with fumonisins depends on the environmental conditions; the maize resistance to contamination and the interaction between both factors. Although the effect of environmental factors is a determinant for establishing the risk of kernel contamination in a region, there is sufficient genetic variability among maize to develop resistance to fumonisin contamination and to breed varieties with contamination at safe levels. In addition, ascertaining which environmental factors are the most important in a region will allow the implementation of risk monitoring programs and suitable cultural practices to reduce the impact of such environmental variables. The current paper reviews all works done to address the influence of environmental variables on fumonisin accumulation, the genetics of maize resistance to fumonisin accumulation, and the search for the biochemical and/or structural mechanisms of the maize plant that could be involved in resistance to fumonisin contamination. We also explore the outcomes of breeding programs and risk monitoring of undertaken projects.

  8. Genetic Factors Involved in Fumonisin Accumulation in Maize Kernels and Their Implications in Maize Agronomic Management and Breeding.

    PubMed

    Santiago, Rogelio; Cao, Ana; Butrón, Ana

    2015-08-01

    Contamination of maize with fumonisins depends on the environmental conditions; the maize resistance to contamination and the interaction between both factors. Although the effect of environmental factors is a determinant for establishing the risk of kernel contamination in a region, there is sufficient genetic variability among maize to develop resistance to fumonisin contamination and to breed varieties with contamination at safe levels. In addition, ascertaining which environmental factors are the most important in a region will allow the implementation of risk monitoring programs and suitable cultural practices to reduce the impact of such environmental variables. The current paper reviews all works done to address the influence of environmental variables on fumonisin accumulation, the genetics of maize resistance to fumonisin accumulation, and the search for the biochemical and/or structural mechanisms of the maize plant that could be involved in resistance to fumonisin contamination. We also explore the outcomes of breeding programs and risk monitoring of undertaken projects. PMID:26308050

  9. Genetic Factors Involved in Fumonisin Accumulation in Maize Kernels and Their Implications in Maize Agronomic Management and Breeding

    PubMed Central

    Santiago, Rogelio; Cao, Ana; Butrón, Ana

    2015-01-01

    Contamination of maize with fumonisins depends on the environmental conditions; the maize resistance to contamination and the interaction between both factors. Although the effect of environmental factors is a determinant for establishing the risk of kernel contamination in a region, there is sufficient genetic variability among maize to develop resistance to fumonisin contamination and to breed varieties with contamination at safe levels. In addition, ascertaining which environmental factors are the most important in a region will allow the implementation of risk monitoring programs and suitable cultural practices to reduce the impact of such environmental variables. The current paper reviews all works done to address the influence of environmental variables on fumonisin accumulation, the genetics of maize resistance to fumonisin accumulation, and the search for the biochemical and/or structural mechanisms of the maize plant that could be involved in resistance to fumonisin contamination. We also explore the outcomes of breeding programs and risk monitoring of undertaken projects. PMID:26308050

  10. Effect of temperature on dopamine transporter function and intracellular accumulation of methamphetamine: implications for methamphetamine-induced dopaminergic neurotoxicity.

    PubMed

    Xie, T; McCann, U D; Kim, S; Yuan, J; Ricaurte, G A

    2000-10-15

    Hyperthermia exacerbates and hypothermia attenuates methamphetamine (METH)-induced dopamine (DA) neurotoxicity. The mechanisms underlying these temperature effects are unknown. Given the essential role of the DA transporter (DAT) in the expression of METH-induced DA neurotoxicity, we hypothesized that the effect of temperature on METH-induced DA neurotoxicity is mediated, at least in part, at the level of the DAT. To test this hypothesis, the effects of small, physiologically relevant temperature changes on DAT function were evaluated in two types of cultured neuronal cells: (1) a neuroblastoma cell line stably transfected with human DAT cDNA and (2) rat embryonic mesencephalic primary cells that naturally express the DAT. Temperatures for studies of DAT function were selected based on core temperature measurements in animals exposed to METH under usual ambient (22 degrees C) and hypothermic (6 degrees C) temperature conditions, where METH neurotoxicity was fully expressed and blocked, respectively. DAT function, determined by measuring accumulation of radiolabeled DA and 1-methyl-4-phenylpyridinium (MPP(+)), was found to directly correlate with temperature, with higher levels of substrate uptake at 40 degrees C, intermediate levels at 37 degrees C, and lower levels at 34 degrees C. DAT-mediated accumulation of METH also directly correlated with temperature, with greater accumulation at higher temperatures. These findings indicate that relatively small, physiologically relevant changes in temperature significantly alter DAT function and intracellular METH accumulation, and suggest that the effect of temperature on METH-induced DA neurotoxicity is mediated, at least in part, at the level of the DAT.

  11. Glucose oxidation and low-density lipoprotein-induced macrophage ceroid accumulation: possible implications for diabetic atherosclerosis.

    PubMed Central

    Hunt, J V; Bottoms, M A; Clare, K; Skamarauskas, J T; Mitchinson, M J

    1994-01-01

    The exposure of proteins to high concentrations of glucose in vitro is widely considered a relevant model of the functional degeneration of tissue occurring in diabetes mellitus. In particular, the enhanced atherosclerosis in diabetes is often discussed in terms of glycation of low-density lipoprotein (LDL), the non-enzymic attachment of glucose to apolipoprotein amino groups. However, glucose can undergo transition-metal-catalysed oxidation under near-physiological conditions in vitro, producing oxidants that possess a reactivity similar to the hydroxyl radical. These oxidants can fragment protein, hydroxylate benzoic acid and induce lipid peroxidation in human LDL. In this study, glycation of LDL in vitro is accompanied by such oxidative processes. However, the oxidation of LDL varies with glucose concentration in a manner which does not parallel changes in protein glycation. Glycation increases in proportion to glucose concentration, whereas in our studies maximal oxidation occurs at a glucose concentration of approx. 25 mM. The modification of LDL resulting from exposure to glucose alters macrophage ceroid accumulation, a process which occurs in the human atherosclerotic plaque. The accumulation of ceroid in macrophages is shown to be related to LDL oxidation rather than LDL glycation, per se, as it too occurs at a maximum of approx. 25 mM. Oxidative sequelae of protein glycation appear to be a major factor in LDL-macrophage interactions, at least with respect to ceroid accumulation. Our observations are discussed in the context of the observed increase in the severity of atherosclerosis in diabetes. PMID:8198540

  12. Accumulation dynamics and acute toxicity of silver nanoparticles to Daphnia magna and Lumbriculus variegatus: implications for metal modeling approaches.

    PubMed

    Khan, Farhan R; Paul, Kai B; Dybowska, Agnieszka D; Valsami-Jones, Eugenia; Lead, Jamie R; Stone, Vicki; Fernandes, Teresa F

    2015-04-01

    Frameworks commonly used in trace metal ecotoxicology (e.g., biotic ligand model (BLM) and tissue residue approach (TRA)) are based on the established link between uptake, accumulation and toxicity, but similar relationships remain unverified for metal-containing nanoparticles (NPs). The present study aimed to (i) characterize the bioaccumulation dynamics of PVP-, PEG-, and citrate-AgNPs, in comparison to dissolved Ag, in Daphnia magna and Lumbriculus variegatus; and (ii) investigate whether parameters of bioavailability and accumulation predict acute toxicity. In both species, uptake rate constants for AgNPs were ∼ 2-10 times less than for dissolved Ag and showed significant rank order concordance with acute toxicity. Ag elimination by L. variegatus fitted a 1-compartment loss model, whereas elimination in D. magna was biphasic. The latter showed consistency with studies that reported daphnids ingesting NPs, whereas L. variegatus biodynamic parameters indicated that uptake and efflux were primarily determined by the bioavailability of dissolved Ag released by the AgNPs. Thus, principles of BLM and TRA frameworks are confounded by the feeding behavior of D. magna where the ingestion of AgNPs perturbs the relationship between tissue concentrations and acute toxicity, but such approaches are applicable when accumulation and acute toxicity are linked to dissolved concentrations. The uptake rate constant, as a parameter of bioavailability inclusive of all available pathways, could be a successful predictor of acute toxicity.

  13. Role of extracellular Hydrogen peroxide in regulation of iron homeostasis genes in neuronal cells: Implication in iron accumulation.

    PubMed

    Dev, Som; Kumari, Sanju; Singh, Neena; Kumar Bal, Saswat; Seth, Pankaj; Mukhopadhyay, Chinmay K

    2015-09-01

    Iron accumulation and oxidative stress are associated with neurodegenerative disease. Labile iron is known to catalyze free radical generation and subsequent neuronal damage, whereas the role of oxidative stress in neuronal iron accumulation is less well understood. Here, we examined the effect of hydrogen peroxide (H2O2) treatment on cellular iron-uptake, -storage, and -release proteins in the neuroblastoma cell line SH-SY5Y. We found no detectable change in the iron-uptake proteins transferrin receptor-1 and divalent metal ion transporter. In contrast, H2O2 treatment resulted in significant degradation of the iron-exporter ferroportin (Fpn). A decrease in Fpn is expected to increase the labile iron pool (LIP), reducing the iron-regulatory protein (IRP)-iron-responsive element interaction and increasing the expression of ferritin-H (Ft-H) for iron storage. Instead, we detected IRP1 activation, presumably due to oxidative stress, and a decrease in Ft-H translation. A reduction in Ft-H mRNA was also observed, probably dependent on an antioxidant-response element present in the Ft-H enhancer. The decrease in Fpn and Ft-H upon H2O2 treatment led to a time-dependent increase in the cellular LIP. Our study reveals a complex regulation of neuronal iron-release and iron-storage components in response to H2O2 that may explain iron accumulation detected in neurodegenerative diseases associated with oxidative stress.

  14. Excess 210Po in 2010 Eyjafjallajökull tephra (Iceland): Evidence for pre-eruptive gas accumulation

    NASA Astrophysics Data System (ADS)

    Sigmarsson, Olgeir; Condomines, Michel; Gauthier, Pierre-Jean

    2015-10-01

    Excess gas phase in magmas erupting explosively is well known worldwide. However, the origin of this gas phase, in excess of what can be dissolved in the erupting magma at depth, and the rate of gas accumulation is less well defined. The 2010 mildly explosive eruption at Eyjafjallajökull, Iceland, produced mingled tephra of benmoreitic and trachytic composition whereas alkali basalt was emitted during preceding flank eruption. Tephra of the first explosive phase are composed of three glass types, alkaline rhyolite, mixed benmoreite, and basalt, which suggests that the basaltic magma intruded a pre-existing rhyolitic magma chamber, and ultimately triggered the eruption. The mixed benmoreitic tephra (erupted on 15 and 17 April 2010) had large 210Po in excess of 210Pb [(210Po /210Pb) 0 = 1.88 ] at the time of eruption, and possibly a small 210Pb excess over its parent 226Ra. In contrast, the preceding flank eruption produced basalt with (210Po) 0 = 0, upon eruption, and the final trachyte had lost most of its 210Po during open-system degassing. The 210Po excess in the first erupted benmoreites is interpreted to result from 210Po degassing of basaltic magma and the accumulation of 210Po-enriched gas, either in the upper part of the basaltic intrusion, below the rhyolite-basalt interface, or in the pre-existing residual rhyolitic magma chamber. From a simple model of radon and polonium accumulation in the rhyolitic reservoir, the ratio of the mass of basalt magma degassing over the mass of magma accumulating the excess gas decreased from 20 to 15 over 2 days, implying zoned magma reservoir, with the uppermost and gas-richest part erupting first. The duration of pre-eruptive gas accumulation in this model is approximately one year. This corresponds closely to the initiation of a seismic swarm beneath Eyjafjallajökull, early June 2009, which was the first pre-eruptive signal detected. The coincidence between initiation of gas accumulation at relatively shallow depth and

  15. Character, paleoenvironment, rate of accumulation, and evidence for seismic triggering of Holocene turbidites, Canada Abyssal Plain, Arctic Ocean

    USGS Publications Warehouse

    Grantz, A.; Phillips, R.L.; Mullen, M.W.; Starratt, S.W.; Jones, Glenn A.; Naidu, A.S.; Finney, B.P.

    1996-01-01

    Four box cores and one piston core show that Holocene sedimentation on the southern Canada Abyssal Plain for the last 8010??120 yr has consisted of a continuing rain of pelagic organic and ice-rafted elastic sediment with a net accumulation rate during the late Holocene of ???10 mm/1000 yr, and episodically emplaced turbidites 1-5 m thick deposited at intervals of 830 to 3450 yr (average 2000 yr). The average net accumulation rate of the mixed sequence of turbidites and thin pelagite interbeds in the cores is about 1.2 m/1000 yr. Physiography suggests that the turbidites originated on the Mackenzie Delta or its clinoform, and ??13C values of -27 to - 25??? in the turbidites are compatible with a provenance on a delta. Extant displaced neritic and lower slope to basin plain calcareous benthic foraminifers coexist in the turbidite units. Their joint occurence indicates that the turbidites originated on the modern continental shelf and entrained sediment from the slope and rise enroute to their final resting place on the Canada Abyssal Plain. The presence of Middle Pleistocene diatoms in the turbidites suggests, in addition, that the turbidites may have originated in shallow submarine slides beneath the upper slope or outer shelf. Small but consistent differences in organic carbon content and ??13C values between the turbidite units suggest that they did not share an identical provenance, which is at least compatible with an origin in slope failures. The primary provenance of the ice-rafted component of the pelagic beds was the glaciated terrane of northwestern Canada; and the provenance of the turbidite units was Pleistocene and Holocene sedimentary deposits on the outer continental shelf and upper slope of the Mackenzie Delta. Largely local derivation of the sediment of the Canada Abyssal Plain indicates that sediment accumulation rates in the Arctic Ocean are valid only for regions with similar depositional sources and processes, and that these rates cannot be

  16. Demise of reef-flat carbonate accumulation with late Holocene sea-level fall: Evidence from Molokai, Hawaii

    USGS Publications Warehouse

    Engels, M.S.; Fletcher, C.H.; Field, M.; Conger, C.L.; Bochicchio, C.

    2008-01-01

    Twelve cores from the protected reef-flat of Molokai revealed that carbonate sediment accumulation, ranging from 3 mm year-1 to less than 1 mm year-1, ended on average 2,500 years ago. Modern sediment is present as a mobile surface veneer but is not trapped within the reef framework. This finding is consistent with the arrest of deposition at the end of the mid-Holocene highstand, known locally as the "Kapapa Stand of the Sea," ???2 m above the present datum ca. 3,500 years ago in the main Hawaiian Islands. Subsequent erosion, non-deposition, and/or a lack of rigid binding were probable factors leading to the lack of reef-flat accumulation during the late Holocene sea-level fall. Given anticipated climate changes, increased sedimentation of reef-flat environments is to be expected as a consequence of higher sea level. ?? 2008 Springer-Verlag.

  17. Riboflavin status, MTHFR genotype and blood pressure: current evidence and implications for personalised nutrition.

    PubMed

    McAuley, E; McNulty, H; Hughes, C; Strain, J J; Ward, M

    2016-08-01

    Clinical deficiency of the B-vitamin riboflavin (vitamin B2) is largely confined to developing countries; however accumulating evidence indicates that suboptimal riboflavin status is a widespread problem across the developed world. Few international data are available on riboflavin status as measured by the functional biomarker, erythrocyte glutathione reductase activation coefficient, considered to be the gold standard index. One important role of riboflavin in the form of flavin dinucleotide is as a co-factor for the folate-metabolising enzyme methylenetetrahydrofolate reductase (MTHFR). Homozygosity for the common C677T polymorphism in MTHFR, affecting over 10 % of the UK and Irish populations and up to 32 % of other populations worldwide, has been associated with an increased risk of CVD, and more recently with hypertension. This review will explore available studies reporting riboflavin status worldwide, the interaction of riboflavin with the MTHFR C677T polymorphism and the potential role of riboflavin in personalised nutrition. Evidence is accumulating for a novel role of riboflavin as an important modulator of blood pressure (BP) specifically in individuals with the MTHFR 677TT genotype, with results from a number of recent randomised controlled trials demonstrating that riboflavin supplementation can significantly reduce systolic BP by 5-13 mmHg in these genetically at risk adults. Studies are however required to investigate the BP-lowering effect of riboflavin in different populations and in response to doses higher than 1·6 mg/d. Furthermore, work focusing on the translation of this research to health professionals and patients is also required.

  18. Riboflavin status, MTHFR genotype and blood pressure: current evidence and implications for personalised nutrition.

    PubMed

    McAuley, E; McNulty, H; Hughes, C; Strain, J J; Ward, M

    2016-08-01

    Clinical deficiency of the B-vitamin riboflavin (vitamin B2) is largely confined to developing countries; however accumulating evidence indicates that suboptimal riboflavin status is a widespread problem across the developed world. Few international data are available on riboflavin status as measured by the functional biomarker, erythrocyte glutathione reductase activation coefficient, considered to be the gold standard index. One important role of riboflavin in the form of flavin dinucleotide is as a co-factor for the folate-metabolising enzyme methylenetetrahydrofolate reductase (MTHFR). Homozygosity for the common C677T polymorphism in MTHFR, affecting over 10 % of the UK and Irish populations and up to 32 % of other populations worldwide, has been associated with an increased risk of CVD, and more recently with hypertension. This review will explore available studies reporting riboflavin status worldwide, the interaction of riboflavin with the MTHFR C677T polymorphism and the potential role of riboflavin in personalised nutrition. Evidence is accumulating for a novel role of riboflavin as an important modulator of blood pressure (BP) specifically in individuals with the MTHFR 677TT genotype, with results from a number of recent randomised controlled trials demonstrating that riboflavin supplementation can significantly reduce systolic BP by 5-13 mmHg in these genetically at risk adults. Studies are however required to investigate the BP-lowering effect of riboflavin in different populations and in response to doses higher than 1·6 mg/d. Furthermore, work focusing on the translation of this research to health professionals and patients is also required. PMID:27170501

  19. Evidence for functional redundancy in arbuscular mycorrhizal fungi and implications for agroecosystem management.

    PubMed

    Gosling, Paul; Jones, Julie; Bending, Gary D

    2016-01-01

    Arbuscular mycorrhizal (AM) fungi provide benefits to host plants and show functional diversity, with evidence of functional trait conservation at the family level. Diverse communities of AM fungi ought therefore to provide increased benefits to the host, with implications for the management of sustainable agroecosystems. However, this is often not evident in the literature, with diversity saturation at low species number. Growth and nutrient uptake were measured in onions in the glasshouse on AM-free phosphorus (P)-poor soil, inoculated with between one and seven species of AM fungi in all possible combinations. Inoculation with AM fungi increased shoot dry weight as well as P and copper concentrations in shoots but reduced the concentration of potassium and sulphur. There was little evidence of increased benefit from high AM fungal diversity, and increasing diversity beyond three species did not result in significantly higher shoot weight or P or Cu concentrations. Species of Glomeraceae had the greatest impact on growth and nutrient uptake, while species of Acaulospora and Racocetra did not have a significant impact. Failure to show a benefit from high AM fungal diversity in this and other studies may be the result of experimental conditions, with the benefits of AM fungal diversity only becoming apparent when the host plant is faced with multiple stress factors. Replicating the complex interactions between AM fungi, the host plant and their environment in the laboratory in order to fully understand these interactions is a major challenge to AM research.

  20. Variation in Patterns of Metal Accumulation in Thallus Parts of Lessonia trabeculata (Laminariales; Phaeophyceae): Implications for Biomonitoring

    PubMed Central

    Sáez, Claudio A.; Lobos, M. Gabriela; Macaya, Erasmo C.; Oliva, Doris; Quiroz, Waldo; Brown, Murray T.

    2012-01-01

    Seaweeds are well known to concentrate metals from seawater and have been employed as monitors of metal pollution in coastal waters and estuaries. However, research showing that various intrinsic and extrinsic factors can influence metal accumulation, raises doubts about the basis for using seaweeds in biomonitoring programmes. The thallus of brown seaweeds of the order Laminariales (kelps) is morphologically complex but there is limited information about the variation in metal accumulation between the different parts, which might result in erroneous conclusions being drawn if not accounted for in the biomonitoring protocol. To assess patterns of individual metals in the differentiated parts of the thallus (blade, stipe, holdfast), concentrations of a wide range of essential and non-essential metals (Fe, Cr, Cu, Zn, Mn, Pb, Cd, Ni and Al) were measured in the kelp Lessonia trabeculata. Seaweeds were collected from three sampling stations located at 5, 30 and 60 m from an illegal sewage outfall close to Ventanas, Chile and from a pristine location at Faro Curaumilla. For the majority of metals the highest concentrations in bottom sediment and seaweed samples were found at the site closest to the outfall, with concentrations decreasing with distance from the outfall and at control stations; the exception was Cd, concentrations of which were higher at control stations. The patterns of metal concentrations in different thallus parts were metal specific and independent of sampling station. These results and the available literature suggest that biomonitoring of metals using seaweeds must take account of differences in the accumulation of metals in thallus parts of complex seaweeds. PMID:23166836

  1. Variation in patterns of metal accumulation in thallus parts of Lessonia trabeculata (Laminariales; Phaeophyceae): implications for biomonitoring.

    PubMed

    Sáez, Claudio A; Lobos, M Gabriela; Macaya, Erasmo C; Oliva, Doris; Quiroz, Waldo; Brown, Murray T

    2012-01-01

    Seaweeds are well known to concentrate metals from seawater and have been employed as monitors of metal pollution in coastal waters and estuaries. However, research showing that various intrinsic and extrinsic factors can influence metal accumulation, raises doubts about the basis for using seaweeds in biomonitoring programmes. The thallus of brown seaweeds of the order Laminariales (kelps) is morphologically complex but there is limited information about the variation in metal accumulation between the different parts, which might result in erroneous conclusions being drawn if not accounted for in the biomonitoring protocol. To assess patterns of individual metals in the differentiated parts of the thallus (blade, stipe, holdfast), concentrations of a wide range of essential and non-essential metals (Fe, Cr, Cu, Zn, Mn, Pb, Cd, Ni and Al) were measured in the kelp Lessonia trabeculata. Seaweeds were collected from three sampling stations located at 5, 30 and 60 m from an illegal sewage outfall close to Ventanas, Chile and from a pristine location at Faro Curaumilla. For the majority of metals the highest concentrations in bottom sediment and seaweed samples were found at the site closest to the outfall, with concentrations decreasing with distance from the outfall and at control stations; the exception was Cd, concentrations of which were higher at control stations. The patterns of metal concentrations in different thallus parts were metal specific and independent of sampling station. These results and the available literature suggest that biomonitoring of metals using seaweeds must take account of differences in the accumulation of metals in thallus parts of complex seaweeds.

  2. Element accumulation patterns of deciduous and evergreen tree seedlings on acid soils: implications for sensitivity to manganese toxicity.

    PubMed

    St Clair, Samuel B; Lynch, Jonathan P

    2005-01-01

    Foliar nutrient imbalances, including the hyperaccumulation of manganese (Mn), are correlated with symptoms of declining health in sensitive tree species growing on acidic forest soils. The objectives of this study were to: (1) compare foliar nutrient accumulation patterns of six deciduous (sugar maple (Acer saccharum Marsh.), red maple (Acer rubrum L.), red oak (Quercus rubra L.), white oak (Quercus alba L.), black cherry (Prunus serotina Ehrh.) and white ash (Fraxinus americana L.)) and three evergreen (eastern hemlock (Tsuga canadensis L.), white pine (Pinus strobus L.) and white spruce (Picea glauca (Moench) Voss.)) tree species growing on acidic forest soils; and (2) examine how leaf phenology and other traits that distinguish evergreen and deciduous tree species influence foliar Mn accumulation rates and sensitivity to excess Mn. For the first objective, leaf samples of seedlings from five acidic, non-glaciated field sites on Pennsylvania's Allegheny Plateau were collected and analyzed for leaf element concentrations. In a second study, we examined growth and photosynthetic responses of seedlings exposed to excess Mn in sand culture. In field samples, Mn in deciduous foliage hyperaccumulated to concentrations more than twice as high as those found in evergreen needles. Among species, sugar maple was the most sensitive to excess Mn based on growth and photosynthetic measurements. Photosynthesis in red maple and red oak was also sensitive to excess Mn, whereas white oak, black cherry, white ash and the three evergreen species were tolerant of excess Mn. Among the nine species, relative rates of photosynthesis were negatively correlated with foliar Mn concentrations, suggesting that photosynthetic sensitivity to Mn is a function of its rate of accumulation in seedling foliage. PMID:15519989

  3. Element accumulation patterns of deciduous and evergreen tree seedlings on acid soils: implications for sensitivity to manganese toxicity.

    PubMed

    St Clair, Samuel B; Lynch, Jonathan P

    2005-01-01

    Foliar nutrient imbalances, including the hyperaccumulation of manganese (Mn), are correlated with symptoms of declining health in sensitive tree species growing on acidic forest soils. The objectives of this study were to: (1) compare foliar nutrient accumulation patterns of six deciduous (sugar maple (Acer saccharum Marsh.), red maple (Acer rubrum L.), red oak (Quercus rubra L.), white oak (Quercus alba L.), black cherry (Prunus serotina Ehrh.) and white ash (Fraxinus americana L.)) and three evergreen (eastern hemlock (Tsuga canadensis L.), white pine (Pinus strobus L.) and white spruce (Picea glauca (Moench) Voss.)) tree species growing on acidic forest soils; and (2) examine how leaf phenology and other traits that distinguish evergreen and deciduous tree species influence foliar Mn accumulation rates and sensitivity to excess Mn. For the first objective, leaf samples of seedlings from five acidic, non-glaciated field sites on Pennsylvania's Allegheny Plateau were collected and analyzed for leaf element concentrations. In a second study, we examined growth and photosynthetic responses of seedlings exposed to excess Mn in sand culture. In field samples, Mn in deciduous foliage hyperaccumulated to concentrations more than twice as high as those found in evergreen needles. Among species, sugar maple was the most sensitive to excess Mn based on growth and photosynthetic measurements. Photosynthesis in red maple and red oak was also sensitive to excess Mn, whereas white oak, black cherry, white ash and the three evergreen species were tolerant of excess Mn. Among the nine species, relative rates of photosynthesis were negatively correlated with foliar Mn concentrations, suggesting that photosynthetic sensitivity to Mn is a function of its rate of accumulation in seedling foliage.

  4. Rates of plant succession, carbon and nitrogen accumulation in small-scale tundra chronosequences; an implication for climate change

    NASA Astrophysics Data System (ADS)

    Kobayashi, M.; Klaminder, J.

    2011-12-01

    The rate in which plants are able to colonize and build up soil organic carbon (SOC) and nitrogen (N) in soil are crucial in understanding the effect of environmental changes on high latitude ecosystems via plant community. In this presentation we present high-spatial-resolution data of plant colonization and SOC and N accumulation rates occurring on frost boils that are common in many periglacial landscapes. The diameters of each frost boil ranges from 1 to 3 meters. The distribution of plant community across a frost boil can be identified as a gradient of ongoing primary succession. The primary succession is initiated in the centre of the frost boil every time up-frozen soil is deposited on top of the surface. A subsequent lateral mass-movement of newly deposited soil from the centre of the frost boil towards the rim over time causes the surface soil and plant community to become progressively "older" from the centre towards the rim of the frost boil. In the presented work we constrain the age of the soil surface as a function of distance from the centre of the frost boil towards the rim by using lichenometry dating. With this investigation, we achieve soil age gradients (chronosequences) ranging from approximately from 0 to 300 years for meters-scale. We present data from northern Sweden where we have utilized this small-scale variation in soil age to understand how the accumulation rate of SOC and N varies over time in the upper 10 cm of the arctic soil and how the accumulation rates is affected by other ecosystem properties such as temperature, plant diversity, dominant plant functional groups and litter quality. Our key conclusions is that reduced soil frost actions, which is likely to accompany the predicted warming of the Scandinavian arctic, are likely to accelerate the colonization rate of vegetation that will enhance the accumulation of SOC and N. However, one likely side effect of this colonization into previously frost-disturbed system is the decline

  5. A fractal model for nuclear organization: current evidence and biological implications

    PubMed Central

    Bancaud, Aurélien; Lavelle, Christophe; Huet, Sébastien; Ellenberg, Jan

    2012-01-01

    Chromatin is a multiscale structure on which transcription, replication, recombination and repair of the genome occur. To fully understand any of these processes at the molecular level under physiological conditions, a clear picture of the polymorphic and dynamic organization of chromatin in the eukaryotic nucleus is required. Recent studies indicate that a fractal model of chromatin architecture is consistent with both the reaction-diffusion properties of chromatin interacting proteins and with structural data on chromatin interminglement. In this study, we provide a critical overview of the experimental evidence that support a fractal organization of chromatin. On this basis, we discuss the functional implications of a fractal chromatin model for biological processes and propose future experiments to probe chromatin organization further that should allow to strongly support or invalidate the fractal hypothesis. PMID:22790985

  6. Extent of Low-accumulation 'Wind Glaze' Areas on the East Antarctic Plateau: Implications for Continental Ice Mass Balance

    NASA Technical Reports Server (NTRS)

    Scambos, Theodore A.; Frezzotti, Massimo; Haran, T.; Bohlander, J.; Lenaerts, J. T. M.; Van Den Broeke, M. R.; Jezek, K.; Long, D.; Urbini, S.; Farness, K.; Neumann, T.; Albert, M.; Winther, J.-G.

    2012-01-01

    Persistent katabatic winds form widely distributed localized areas of near-zero net surface accumulation on the East Antarctic ice sheet (EAIS) plateau. These areas have been called 'glaze' surfaces due to their polished appearance. They are typically 2-200 square kilometers in area and are found on leeward slopes of ice-sheet undulations and megadunes. Adjacent, leeward high-accumulation regions (isolated dunes) are generally smaller and do not compensate for the local low in surface mass balance (SMB). We use a combination of satellite remote sensing and field-gathered datasets to map the extent of wind glaze in the EAIS above 1500m elevation. Mapping criteria are derived from distinctive surface and subsurface characteristics of glaze areas resulting from many years of intense annual temperature cycling without significant burial. Our results show that 11.2 plus or minus 1.7%, or 950 plus or minus 143 x 10(exp 3) square kilometers, of the EAIS above 1500m is wind glaze. Studies of SMB interpolate values across glaze regions, leading to overestimates of net mass input. Using our derived wind-glaze extent, we estimate this excess in three recent models of Antarctic SMB at 46-82 Gt. The lowest-input model appears to best match the mean in regions of extensive wind glaze.

  7. Evidence that specific mtDNA point mutations may not accumulate in skeletal muscle during normal human aging.

    PubMed Central

    Pallotti, F.; Chen, X.; Bonilla, E.; Schon, E. A.

    1996-01-01

    It is unclear at present whether specific mtDNA point mutations accumulate during normal human aging. In order to address this question, we used quantitative PCR of total DNA isolated from skeletal muscle from normal individuals of various ages to search for the presence and amount of spontaneous mtDNA point mutations in two small regions of the human mitochondrial genome. We observed low levels of somatic mutations above background in both regions, but there was no correlation between the amount of mutation detected and the age of the subject. These results contrasted with our finding of an age-related increase in the amount of the mtDNA "common deletion" in these very samples. Thus, it appears that both somatic mtDNA point mutations and mtDNA deletions can arise at low frequency in normal individuals but that, unlike deletions, there is no preferential amplification or accumulation of specific point mutations in skeletal muscle over the course of the normal human life span. Images Figure 2 Figure 3 Figure 4 Figure 5 PMID:8751860

  8. Microcystin accumulation in cladocerans: first evidence of MC uptake from aqueous extracts of a natural bloom sample.

    PubMed

    Ferrão-Filho, Aloysio S; Herrera, Natalia A; Echeverri, Luis Fernando

    2014-09-01

    Bioaccumulation of microcystins (MC) in zooplankton has been shown in several studies, mainly in field samples. A few studies, however, have demonstrated MC bioaccumulation in laboratory experiments. Although ingestion of cell-bound MC is considered the main route of MC accumulation, another important source is the MC from the dissolved fraction (DMC). This study reports the accumulation of DMC from aqueous extracts of natural bloom samples in three cladoceran species: Moina micrura, Daphnia laevis and Daphnia similis. Animals were exposed for 96 h to aqueous extracts of lyophilized matter from two bloom samples from Colombian reservoirs in different concentrations (25-1000 mg DW L(-1)). Analysis by HPLC-MS detected MC-LR in these samples at concentrations of 434-538 μg g(-1). For the analysis of MC in animal tissues the samples were homogenized and sonicated in methanol:water (75%) and analyzed by ELISA. Results showed that the animals uptake of MC increased with increasing exposure concentrations of aqueous extracts, with M. micrura and D. laevis clones presenting the highest MC concentrations in their tissues (up to 1170-1260 μg g(-1)) while D. similis the lowest (184 μg g(-1)). This study shows, for the first time, that MC uptake from dissolved fraction by zooplankton is possible, not only from the ingestion of seston or cell-bound MC as previously demonstrated. PMID:24880137

  9. Chloride Accumulators NKCC1 and AE2 in Mouse GnRH Neurons: Implications for GABAA Mediated Excitation.

    PubMed

    Taylor-Burds, Carol; Cheng, Paul; Wray, Susan

    2015-01-01

    A developmental "switch" in chloride transporters occurs in most neurons resulting in GABAA mediated hyperpolarization in the adult. However, several neuronal cell subtypes maintain primarily depolarizing responses to GABAA receptor activation. Among this group are gonadotropin-releasing hormone-1 (GnRH) neurons, which control puberty and reproduction. NKCC1 is the primary chloride accumulator in neurons, expressed at high levels early in development and contributes to depolarization after GABAA receptor activation. In contrast, KCC2 is the primary chloride extruder in neurons, expressed at high levels in the adult and contributes to hyperpolarization after GABAA receptor activation. Anion exchangers (AEs) are also potential modulators of responses to GABAA activation since they accumulate chloride and extrude bicarbonate. To evaluate the mechanism(s) underlying GABAA mediated depolarization, GnRH neurons were analyzed for 1) expression of chloride transporters and AEs in embryonic, pre-pubertal, and adult mice 2) responses to GABAA receptor activation in NKCC1-/- mice and 3) function of AEs in these responses. At all ages, GnRH neurons were immunopositive for NKCC1 and AE2 but not KCC2 or AE3. Using explants, calcium imaging and gramicidin perforated patch clamp techniques we found that GnRH neurons from NKCC1-/- mice retained relatively normal responses to the GABAA agonist muscimol. However, acute pharmacological inhibition of NKCC1 with bumetanide eliminated the depolarization/calcium response to muscimol in 40% of GnRH neurons from WT mice. In the remaining GnRH neurons, HCO3- mediated mechanisms accounted for the remaining calcium responses to muscimol. Collectively these data reveal mechanisms responsible for maintaining depolarizing GABAA mediated transmission in GnRH neurons. PMID:26110920

  10. Genome-wide scans provide evidence for positive selection of genes implicated in Lassa fever

    PubMed Central

    Andersen, Kristian G.; Shylakhter, Ilya; Tabrizi, Shervin; Grossman, Sharon R.; Happi, Christian T.; Sabeti, Pardis C.

    2012-01-01

    Rapidly evolving viruses and other pathogens can have an immense impact on human evolution as natural selection acts to increase the prevalence of genetic variants providing resistance to disease. With the emergence of large datasets of human genetic variation, we can search for signatures of natural selection in the human genome driven by such disease-causing microorganisms. Based on this approach, we have previously hypothesized that Lassa virus (LASV) may have been a driver of natural selection in West African populations where Lassa haemorrhagic fever is endemic. In this study, we provide further evidence for this notion. By applying tests for selection to genome-wide data from the International Haplotype Map Consortium and the 1000 Genomes Consortium, we demonstrate evidence for positive selection in LARGE and interleukin 21 (IL21), two genes implicated in LASV infectivity and immunity. We further localized the signals of selection, using the recently developed composite of multiple signals method, to introns and putative regulatory regions of those genes. Our results suggest that natural selection may have targeted variants giving rise to alternative splicing or differential gene expression of LARGE and IL21. Overall, our study supports the hypothesis that selective pressures imposed by LASV may have led to the emergence of particular alleles conferring resistance to Lassa fever, and opens up new avenues of research pursuit. PMID:22312054

  11. Evolutionary Evaluation: implications for evaluators, researchers, practitioners, funders and the evidence-based program mandate.

    PubMed

    Urban, Jennifer Brown; Hargraves, Monica; Trochim, William M

    2014-08-01

    Evolutionary theory, developmental systems theory, and evolutionary epistemology provide deep theoretical foundations for understanding programs, their development over time, and the role of evaluation. This paper relates core concepts from these powerful bodies of theory to program evaluation. Evolutionary Evaluation is operationalized in terms of program and evaluation evolutionary phases, which are in turn aligned with multiple types of validity. The model of Evolutionary Evaluation incorporates Chen's conceptualization of bottom-up versus top-down program development. The resulting framework has important implications for many program management and evaluation issues. The paper illustrates how an Evolutionary Evaluation perspective can illuminate important controversies in evaluation using the example of the appropriate role of randomized controlled trials that encourages a rethinking of "evidence-based programs". From an Evolutionary Evaluation perspective, prevailing interpretations of rigor and mandates for evidence-based programs pose significant challenges to program evolution. This perspective also illuminates the consequences of misalignment between program and evaluation phases; the importance of supporting both researcher-derived and practitioner-derived programs; and the need for variation and evolutionary phase diversity within portfolios of programs.

  12. The deep accumulation of 10Be at Utsira, southwestern Norway: Implications for cosmogenic nuclide exposure dating in peripheral ice sheet landscapes

    NASA Astrophysics Data System (ADS)

    Briner, Jason P.; Goehring, Brent M.; Mangerud, Jan; Svendsen, John Inge

    2016-09-01

    Cosmogenic nuclide exposure dating is a widely used method for constraining past ice sheet histories. We scrutinize a recently published data set of cosmogenic 10Be data from erratic boulders in Norway used to constrain the deglaciation of the western Scandinavian Ice Sheet to 20 ka. Our model of the 10Be inventory in glacial surfaces leads us to conclude that the chronology may be afflicted by the deep subsurface accumulation of 10Be during long-lasting ice-free periods that resulted in 10Be ages >10% too old. We suggest that the majority of the dated erratic boulders contain a uniform level of inherited muon-produced 10Be and were derived from bedrock depths >2.5 m and most likely ~4 m. The implication of our finding is that for landscapes that experience long ice-free periods between brief maximum glacial phases, glacial erosion of >5 m is required to remove detectable traces of inherited 10Be.

  13. Influence of Vegetation on Sediment Accumulation in Restored Tidal Saltmarshes: Field Evidence from the Blackwater Estuary, Essex, UK

    NASA Astrophysics Data System (ADS)

    Price, D.; French, J.; Burningham, H.

    2013-12-01

    Tidal saltmarshes in the UK, and especially in the estuaries of southeast England, have been subject to degradation and erosion over the last few decades, primarily caused by sea-level rise and coastal squeeze due to fixed coastal defences. This is of great concern to a range of coastal stakeholders due to the corresponding loss of functions and services associated with these systems. The coastal defence role that saltmarshes play is well established, and the importance of saltmarsh ecosystems as habitats for birds, fish, and other species is evidenced in the fact that a large proportion of saltmarsh in the southeast England is designated for its scientific and conservation significance. Sediment accumulation is critical for the maintenance of marsh elevation within the tidal frame and for delivery of the aforementioned functions and services. Although many studies have examined accumulation processes, key questions have yet to be fully tested through intensive field observations. One such question relates to the role of vegetation in mediating the retention of newly introduced sediment, as recent research has called into doubt the traditional view of halophytes significantly enhancing rates of sedimentation through wave dissipation. This study presents early results from a project designed to advance our understanding of the processes controlling sediment accumulation. The research focuses on the UK's first large-scale experimental managed flood defence realignment at Tollesbury, Blackwater estuary, Essex. The seawall protecting 21ha of reclaimed agricultural land was artificially breached in 1995 and saltmarsh has progressively developed as tidal exchange has introduced fine sediment into the site. Results from a 12 month monitoring campaign involving hierarchical two-week sediment trap deployments indicates that the role of vegetation in marsh development is less clear cut that previously thought. Gross sedimentation rates were generally higher in non

  14. Genetic evidence that culling increases badger movement: implications for the spread of bovine tuberculosis.

    PubMed

    Pope, Lisa C; Butlin, Roger K; Wilson, Gavin J; Woodroffe, Rosie; Erven, Kristien; Conyers, Chris M; Franklin, Tanya; Delahay, Richard J; Cheeseman, Chris L; Burke, Terry

    2007-12-01

    The Eurasian badger (Meles meles) has been implicated in the transmission of bovine tuberculosis (TB, caused by Mycobacterium bovis) to cattle. However, evidence suggests that attempts to reduce the spread of TB among cattle in Britain by culling badgers have mixed effects. A large-scale field experiment (the randomized badger culling trial, RBCT) showed that widespread proactive badger culling reduced the incidence of TB in cattle within culled areas but that TB incidence increased in adjoining areas. Additionally, localized reactive badger culling increased the incidence of TB in cattle. It has been suggested that culling-induced perturbation of badger social structure may increase individual movements and elevate the risk of disease transmission between badgers and cattle. Field studies support this hypothesis, by demonstrating increases in badger group ranges and the prevalence of TB infection in badgers following culling. However, more evidence on the effect of culling on badger movements is needed in order to predict the epidemiological consequences of this control strategy. Here, analysis of the genetic signatures of badger populations in the RBCT revealed increased dispersal following culling. While standard tests provided evidence for greater dispersal after culling, a novel method indicated that this was due to medium- and long-distance dispersal, in addition to previously reported increases in home-range size. Our results also indicated that, on average, badgers infected with M. bovis moved significantly farther than did uninfected badgers. A disease control strategy that included culling would need to take account of the potentially negative epidemiological consequences of increased badger dispersal. PMID:17944854

  15. A Childbirth Educator’s Commentary on Hormonal Physiology of Childbearing: Evidence and Implications for Women, Babies, and Maternity Care

    PubMed Central

    Amis, Debby

    2015-01-01

    ABSTRACT Sarah Buckley’s game-changing report, Hormonal Physiology of Childbearing: Evidence and Implications for Women, Babies, and Maternity Care, provides the evidence that supporting, promoting, and protecting the normal physiology of childbirth produces the best outcomes for mothers and babies. In this article, a childbirth educator recommends key points from Buckley’s report that should be included in Lamaze childbirth education classes. PMID:26834436

  16. Crystal accumulation and compositional trends in a calc-alkaline batholith: implications for correlation of plutonic and volcanic rocks

    NASA Astrophysics Data System (ADS)

    Barnes, C. G.; Coint, N.

    2013-12-01

    The Wooley Creek batholith is a tilted, calc-alkaline intrusive complex in the Klamath Mountain province, California, that can be divided into two main zones: lower (~159.2 × 0.2 Ma) and upper (~158.2 × 0.3 Ma), separated by a central transition zone. The lower zone consists of multiple intrusive units of gabbro through tonalite, with minor mafic synplutonic dikes and intrusive melagabbro and pyroxenite. Major and trace element data plot in two groups: a mafic group that encompasses pyroxenite to diorite, and a tonalitic group. For each group, Mg/Fe in augite was used to determine the approximate composition of equilibrium melt and then major element mass balance was used to calculate proportions of cumulate phases and melt. For the mafic group, no single parental magma can be identified, which is consistent with assembly via many magma batches. However, the most mafic rocks were derived from basaltic andesite magmas and represent 30 to 100% cumulate augite + opx × plagioclase × olivine. Interstitial melt in the tonalitic group was dacitic, and mass balance indicates from 30 to 80% cumulate pyroxenes + plagioclase × accessory apatite and Fe-Ti oxides. The parental magma was probably silicic andesite. The upper zone varies gradationally from structurally low quartz diorite to uppermost granite. Upper zone magmas ';leaked' to form dacitic to rhyodacitic ';roof dikes'. Previous work (Coint et al., Geosphere, in press) showed that the upper zone formed from an approximately homogeneous magma body and that compositional variation was related to upward percolation of melt. Mass balance supports this interpretation and indicates that (1) the parental magmas were andesitic, (2) structurally low rocks are 15 to 65 % cumulate hornblende + plagioclase × pyroxene, and (3) high-level granite and granodiorite are the fractionated products of this accumulation. These results show that the upper zone is a good example of fractional crystallization within a moderate

  17. Differences in carotenoid accumulation among three feeder-cricket species: implications for carotenoid delivery to captive insectivores.

    PubMed

    Ogilvy, Victoria; Fidgett, Andrea L; Preziosi, Richard F

    2012-01-01

    There are a limited number of feeder-invertebrates available to feed captive insectivores, and many are deficient in certain nutrients. Gut-loading is used to increase the diversity of nutrients present in the captive insectivore diet; however, little is known about delivery of carotenoids via gut-loading. Carotenoids may influence health and reproduction due to their roles in immune and antioxidant systems. We assessed interspecific variation in carotenoid accumulation and retention in three feeder-cricket species (Gryllus bimaculatus, Gryllodes sigillatus and Acheta domesticus) fed one of three diets (wheat-bran, fish-food based formulated diet, and fresh fruit and vegetables). Out of the three species of feeder-cricket in the fish-food-based dietary treatment group, G. bimaculatus had the greatest total carotenoid concentration. All cricket species fed the wheat-bran diet had very low carotenoid concentrations. Species on the fish-food-based diet had intermediate carotenoid concentrations, and those on the fruit and vegetable diet had the highest concentrations. Carotenoid retention was poor across all species. Overall, this study shows that, by providing captive insectivores with G. bimaculatus crickets recently fed a carotenoid-rich diet, the quantity of carotenoids in the diet can be increased.

  18. EXPOSURE TO INTERMITTENT AIR POLLUTION AND CHANGES IN SEMEN QUALITY: EVIDENCE FOR AN ASSOCIATION AND IMPLICATIONS FOR REPRODUCTIVE RISK ASSESSMENT

    EPA Science Inventory

    Exposure to Intermittent Air Pollution and Changes in Semen Quality:
    Evidence for an Association and Implications for Reproductive Risk Assessment.

    S. D. Perreault1, S.G. Selevan2, J. Rubes3, D. Zudova3, and D.P. Evenson4
    1US EPA, ORD/NHEERL, Research Triangle Pa...

  19. Quaternary Sediment Accumulation in the Aleutian Trench: Implications for Dehydration Reaction Progress and Pore Pressure Development Offshore Alaska

    NASA Astrophysics Data System (ADS)

    Meridth, L. N.; Screaton, E.; Jaeger, J. M.; James, S. R.; Villaseñor, T. G.

    2015-12-01

    Sediment inputs to subduction zones impart a significant control on diagenetic reaction progress, fluid production and pore pressure development and thus affect hydrologic and tectonic behavior during subduction. Intensified glaciation following the mid-Pleistocene transition increased sediment flux to the Gulf of Alaska. Rapid sediment accumulation (>1 km/my) in the Aleutian Trench increases overburden and should accelerate dehydration of hydrous sedimentary components by elevating temperatures in the incoming sediment column. These processes have the potential to generate fluid overpressures in the mud-dominated, low permeability sediments deposited on the incoming plate, offshore SE Alaska. Mineralogical analyses on incoming sediments from Deep Sea Drilling Project Leg 18 and Integrated Ocean Drilling Program Expedition 341 show that both smectite and Opal-A are present as hydrous mineral phases. A 1-D numerical model was developed to track dehydration reaction progress and pore pressures in the incoming sediment column from the abyssal plain to the Aleutian Trench. Simulated temperatures in the incoming column increase due to the insulating effect of trench sediments. As a result, trench sedimentation causes smectite dehydration to begin and Opal-A dehydration to nearly reach completion at the deformation front. Simulated excess pore pressures in the proto-decollement zone increase from nearly hydrostatic to almost half of lithostatic due to the rapid deposition of trench sediments. The 1-D modeling results were incorporated into a 2-D model that follows the underthrust column at the deformation front into the subduction zone. Simulated results of the 2-D flow model illustrate the effects of lateral flow on pore pressure distribution following subduction.

  20. An Extraordinary Accumulation of (-)-Pinoresinol in Cell-Free Extracts of Forsythia intermedia: Evidence for Enantiospecific Reduction of (+)-Pinoresinol

    NASA Technical Reports Server (NTRS)

    Katayama, Takeshi; Davin, Laurence B.; Lewis, Norman G.

    1992-01-01

    Stereoselective and enantiospecific transformation mechanisms in lignan biogenesis are only now yielding to scientific inquiry: it has been shown that soluble cell-free preparations from Forsythia intermedia catalysis the formation of the enantiomerically pure lignan, (-)-secoisolariciresinol, when incubated with coniferyl alcohol in the presence of NAD(P)H and H2O2. Surprisingly, (-)-pinoresinol also accumulates in this soluble cell-free assay mixture in greater than 96% enantiomeric excess, even though it is not the naturally occurring antipode present in Forsythia sp. But these soluble cell-free preparations do not engender stereoselective coupling; instead, racemic pinoresinols are first formed, catalysed by an H2O2-dependent peroxidase reaction. An enantiospecific NAD(P)H reductase then converts (+)- pinoresinol, and not the (-)-antipode, into (-)-secoisolariciresinol. Stereoselective syntheis of(+)-pinoresinol from E-coniferyl alcohol is, however, catalysed by an insoluble enzyme preparation in F. suspensa, obtained following removal of readily soluble and ionically bound enzymes; no exogenously supplied cofactors were required other than oxygen, although the reaction was stimulated by NAD-malate addition. Thus, the overall biochemical pathway to enantiomerically pure (-)-secoisolariciresinol has been delineated.

  1. An extraordinary accumulation of (-)-pinoresinol in cell-free extracts of Forsythia intermedia: evidence for enantiospecific reduction of (+)-pinoresinol.

    PubMed

    Katayama, T; Davin, L B; Lewis, N G

    1992-11-01

    Stereoselective and enantiospecific transformation mechanisms in lignan biogenesis are only now yielding to scientific inquiry: it has been shown that soluble cell-free preparations from Forsythia intermedia catalyse the formation of the enantiomerically pure lignan, (-)-secoisolariciresinol, when incubated with coniferyl alcohol in the presence of NAD(P)H and H2O2. Surprisingly, (-)-pinoresinol also accumulates in this soluble cell-free assay mixture in > 96% enantiomeric excess, even though it is not the naturally occurring antipode present in Forsythia sp. But these soluble cell-free preparations do not engender stereoselective coupling; instead, racemic pinoresinols are first formed, catalysed by an H2O2-dependent peroxidase reaction. An enantiospecific NAD(P)H reductase then converts (+)-pinoresinol, and not the (-)-antipode, into (-)-secoisolariciresinol. Stereoselective synthesis [correction of syntheis] of (+)-pinoresinol from E-coniferyl alcohol is, however, catalysed by an insoluble enzyme preparation in F. suspensa, obtained following removal of readily soluble and ionically bound enzymes; no exogenously supplied cofactors were required other than oxygen, although the reaction was stimulated by NAD-malate addition. Thus, the overall biochemical pathway to enantiomerically pure (-)-secoisolariciresinol has been delineated.

  2. [New model of accumulation and agro-business: the ecological and epidemiological implications of the Ecuadorian cut flower production].

    PubMed

    Breilh, Jaime

    2007-01-01

    The article refers to the results of an integrative research project that aim to analyze ecosystem and human health's impacts of cut flower production in Cuencas del Rio Grande region (Cayambe and Tabacundo zones). In order to assess the complex object of study and its multiple dimensions, an interdisciplinary approach has been constructed, based on the following components: a) pesticides dynamics analysis; b) pesticides distribution and commercialization processes in the region; c) economic and anthropological transformation determinate by the flower production; d) epidemiological process of human health impacts; e) and the design of participatory, multicultural and integrative information. The research consolidated an important geo-codified data base on the impacts of cut flower production to workers, communities, aquatic systems and soils, offering evidences of the actual flower production system severe impacts and leading to a reflection about the sustainability of the productive systems and the future of the ecosystems.

  3. Temporal characterization of mercury accumulation at different trophic levels and implications for metal biomagnification along a coastal food web.

    PubMed

    Cardoso, P G; Pereira, E; Duarte, A C; Azeiteiro, U M

    2014-10-15

    The main goal of this study was to assess temporal mercury variations along an estuarine food web to evaluate the mercury contamination level of the system and the risks that humans are exposed to, due to mercury biomagnification. The highest mercury concentrations in the sediments and primary producers (macrophytes) were observed during winter sampling. Instead, the highest mercury concentrations in the water, suspended particulate matter as well as in the zooplanktonic and suprabenthic communities were observed during summer sampling. Evidences of mercury biomagnification along the food web were corroborated by the positive biomagnification factors, particularly for omnivorous macrobenthic species. Comparing the mercury levels at distinct components with several environmental quality criteria it suggests that sediments, water and edible species (e.g., bivalve Scrobicularia plana and the crustacean Carcinus maenas) presented higher mercury levels than the values accepted by legislation which represent a matter of concern for the environment and human health. PMID:25172612

  4. Rapid and frequent turbidite accumulation in the bottom of Izu-Ogasawara Trench: Chemical and radiochemical evidence

    NASA Astrophysics Data System (ADS)

    Nozaki, Yoshiyuki; Ohta, Yoichi

    1993-12-01

    Two sediment cores (pilot gravity and piston) were obtained from the bottom of the Izu-Ogasawara Trench at 9750 m and analyzed for various elements and radioisotopes. The results showed a history of complex and frequent turbidite deposition: In the gravity core, eight layers rich in manganese were observed, of which five are enriched in Cu and Co as well. The other three are also enriched in Mo but no other heavy metals, suggesting the presence of at least two mechanisms of formation. Trapping of iron manganese micronodules can account for the enrichment of Mn, Cu and Co. The other three layers rich in Mn and Mo appear to be formed by a post-depositional diagenetic process of Mn mobilization and redeposition in the sediment column. A strong correlation between Ra-226 and Cu in the gravity core suggests that the Ra-226 was also carried into the bottom of the trench in turbidites in association with Mn micronodules. Little excess of Pb-210 over Ra-226 was found at the top but the excess was significant at mid-depths from 30 to 70 cm, indicating that those sediments were deposited within the last 200 y. In the piston core there is a sharp discontinuity of chemical and radiochemical composition around a depth of 250 cm. Below that depth the sediments appear to be dominated by materials derived from terrestrial sources, as compared with those in the upper layer which are of contemporary marine origin. Ra-226 is deficient relative to Th-230 throughout the sediment column down to about 6 m. This finding is consistent with the finding that the average rate of sediment accumulation is 1-2 orders of magnitude faster than that in the western North Pacific abyssal plain, suggesting the convergence of materials into the bottom of the trench.

  5. The free-radical damage theory: Accumulating evidence against a simple link of oxidative stress to ageing and lifespan.

    PubMed

    Speakman, John R; Selman, Colin

    2011-04-01

    Recent work on a small European cave salamander (Proteus anguinus) has revealed that it has exceptional longevity, yet it appears to have unexceptional defences against oxidative damage. This paper comes at the end of a string of other studies that are calling into question the free-radical damage theory of ageing. This theory rose to prominence in the 1990s as the dominant theory for why we age and die. Despite substantial correlative evidence to support it, studies in the last five years have raised doubts over its importance. In particular, these include studies of mice with the major antioxidant genes knocked out (both singly and in combination), which show the expected elevation in oxidative damage but no impact on lifespan. Combined, these findings raise fundamental questions over whether the free-radical damage theory remains useful for understanding the ageing process, and variation in lifespan and life histories.

  6. Micro and nano-size pores of clay minerals in shale reservoirs: Implication for the accumulation of shale gas

    NASA Astrophysics Data System (ADS)

    Chen, Shangbin; Han, Yufu; Fu, Changqin; Zhang, han; Zhu, Yanming; Zuo, Zhaoxi

    2016-08-01

    A pore is an essential component of shale gas reservoirs. Clay minerals are the adsorption carrier second only to organic matter. This paper uses the organic maturity test, Field-Emission Scanning Electron Microscopy (FE-SEM), and X-ray Diffraction (XRD) to study the structure and effect of clay minerals on storing gas in shales. Results show the depositional environment and organic maturity influence the content and types of clay minerals as well as their structure in the three types of sedimentary facies in China. Clay minerals develop multi-size pores which shrink to micro- and nano-size by close compaction during diagenesis. Micro- and nano-pores can be divided into six types: 1) interlayer, 2) intergranular, 3) pore and fracture in contact with organic matter, 4) pore and fracture in contact with other types of minerals, 5) dissolved and, 6) micro-cracks. The contribution of clay minerals to the presence of pores in shale is evident and the clay plane porosity can even reach 16%, close to the contribution of organic matter. The amount of clay minerals and pores displays a positive correlation. Clay minerals possess a strong adsorption which is affected by moisture and reservoir maturity. Different pore levels of clay minerals are mutually arranged, thus essentially producing distinct reservoir adsorption effects. Understanding the structural characteristics of micro- and nano-pores in clay minerals can provide a tool for the exploration and development of shale gas reservoirs.

  7. A Bidirectional Relationship between Executive Function and Health Behavior: Evidence, Implications, and Future Directions

    PubMed Central

    Allan, Julia L.; McMinn, David; Daly, Michael

    2016-01-01

    Physically active lifestyles and other health-enhancing behaviors play an important role in preserving executive function into old age. Conversely, emerging research suggests that executive functions facilitate participation in a broad range of healthy behaviors including physical activity and reduced fatty food, tobacco, and alcohol consumption. They do this by supporting the volition, planning, performance monitoring, and inhibition necessary to enact intentions and override urges to engage in health damaging behavior. Here, we focus firstly on evidence suggesting that health-enhancing behaviors can induce improvements in executive function. We then switch our focus to findings linking executive function to the consistent performance of health-promoting behaviors and the avoidance of health risk behaviors. We suggest that executive function, health behavior, and disease processes are interdependent. In particular, we argue that a positive feedback loop may exist whereby health behavior-induced changes in executive function foster subsequent health-enhancing behaviors, which in turn help sustain efficient executive functions and good health. We conclude by outlining the implications of this reciprocal relationship for intervention strategies, the design of research studies, and the study of healthy aging. PMID:27601977

  8. A Bidirectional Relationship between Executive Function and Health Behavior: Evidence, Implications, and Future Directions

    PubMed Central

    Allan, Julia L.; McMinn, David; Daly, Michael

    2016-01-01

    Physically active lifestyles and other health-enhancing behaviors play an important role in preserving executive function into old age. Conversely, emerging research suggests that executive functions facilitate participation in a broad range of healthy behaviors including physical activity and reduced fatty food, tobacco, and alcohol consumption. They do this by supporting the volition, planning, performance monitoring, and inhibition necessary to enact intentions and override urges to engage in health damaging behavior. Here, we focus firstly on evidence suggesting that health-enhancing behaviors can induce improvements in executive function. We then switch our focus to findings linking executive function to the consistent performance of health-promoting behaviors and the avoidance of health risk behaviors. We suggest that executive function, health behavior, and disease processes are interdependent. In particular, we argue that a positive feedback loop may exist whereby health behavior-induced changes in executive function foster subsequent health-enhancing behaviors, which in turn help sustain efficient executive functions and good health. We conclude by outlining the implications of this reciprocal relationship for intervention strategies, the design of research studies, and the study of healthy aging.

  9. The Implication of Using NVivo Software in Qualitative Data Analysis: Evidence-Based Reflections.

    PubMed

    Zamawe, F C

    2015-03-01

    For a long time, electronic data analysis has been associated with quantitative methods. However, Computer Assisted Qualitative Data Analysis Software (CAQDAS) are increasingly being developed. Although the CAQDAS has been there for decades, very few qualitative health researchers report using it. This may be due to the difficulties that one has to go through to master the software and the misconceptions that are associated with using CAQDAS. While the issue of mastering CAQDAS has received ample attention, little has been done to address the misconceptions associated with CAQDAS. In this paper, the author reflects on his experience of interacting with one of the popular CAQDAS (NVivo) in order to provide evidence-based implications of using the software. The key message is that unlike statistical software, the main function of CAQDAS is not to analyse data but rather to aid the analysis process, which the researcher must always remain in control of. In other words, researchers must equally know that no software can analyse qualitative data. CAQDAS are basically data management packages, which support the researcher during analysis.

  10. Generic statements require little evidence for acceptance but have powerful implications

    PubMed Central

    Cimpian, Andrei; Brandone, Amanda C.; Gelman, Susan A.

    2010-01-01

    Generic statements (e.g., “Birds lay eggs”) express generalizations about categories. In this paper, we hypothesized that there is a paradoxical asymmetry at the core of generic meaning, such that these sentences have extremely strong implications but require little evidence to be judged true. Four experiments confirmed the hypothesized asymmetry: Participants interpreted novel generics such as “Lorches have purple feathers” as referring to nearly all lorches, but they judged the same novel generics to be true given a wide range of prevalence levels (e.g., even when only 10% or 30% of lorches had purple feathers). A second hypothesis, also confirmed by the results, was that novel generic sentences about dangerous or distinctive properties would be more acceptable than generic sentences that were similar but did not have these connotations. In addition to clarifying important aspects of generics’ meaning, these findings are applicable to a range of real-world processes such as stereotyping and political discourse. PMID:21116475

  11. The Implication of Using NVivo Software in Qualitative Data Analysis: Evidence-Based Reflections.

    PubMed

    Zamawe, F C

    2015-03-01

    For a long time, electronic data analysis has been associated with quantitative methods. However, Computer Assisted Qualitative Data Analysis Software (CAQDAS) are increasingly being developed. Although the CAQDAS has been there for decades, very few qualitative health researchers report using it. This may be due to the difficulties that one has to go through to master the software and the misconceptions that are associated with using CAQDAS. While the issue of mastering CAQDAS has received ample attention, little has been done to address the misconceptions associated with CAQDAS. In this paper, the author reflects on his experience of interacting with one of the popular CAQDAS (NVivo) in order to provide evidence-based implications of using the software. The key message is that unlike statistical software, the main function of CAQDAS is not to analyse data but rather to aid the analysis process, which the researcher must always remain in control of. In other words, researchers must equally know that no software can analyse qualitative data. CAQDAS are basically data management packages, which support the researcher during analysis. PMID:26137192

  12. A Bidirectional Relationship between Executive Function and Health Behavior: Evidence, Implications, and Future Directions.

    PubMed

    Allan, Julia L; McMinn, David; Daly, Michael

    2016-01-01

    Physically active lifestyles and other health-enhancing behaviors play an important role in preserving executive function into old age. Conversely, emerging research suggests that executive functions facilitate participation in a broad range of healthy behaviors including physical activity and reduced fatty food, tobacco, and alcohol consumption. They do this by supporting the volition, planning, performance monitoring, and inhibition necessary to enact intentions and override urges to engage in health damaging behavior. Here, we focus firstly on evidence suggesting that health-enhancing behaviors can induce improvements in executive function. We then switch our focus to findings linking executive function to the consistent performance of health-promoting behaviors and the avoidance of health risk behaviors. We suggest that executive function, health behavior, and disease processes are interdependent. In particular, we argue that a positive feedback loop may exist whereby health behavior-induced changes in executive function foster subsequent health-enhancing behaviors, which in turn help sustain efficient executive functions and good health. We conclude by outlining the implications of this reciprocal relationship for intervention strategies, the design of research studies, and the study of healthy aging. PMID:27601977

  13. Populations of High-Luminosity Density-Bounded HII Regions in Spiral Galaxies? Evidence and Implications

    NASA Technical Reports Server (NTRS)

    Beckman, J. E.; Rozas, M.; Zurita, A.; Watson, R. A.; Knapen, J. H.

    2000-01-01

    In this paper we present evidence that the H II regions of high luminosity in disk galaxies may be density bounded, so that a significant fraction of the ionizing photons emitted by their exciting OB stars escape from the regions. The key piece of evidence is the presence, in the Ha luminosity functions (LFs) of the populations of H iI regions, of glitches, local sharp peaks at an apparently invariant luminosity, defined as the Stromgren luminosity Lstr), LH(sub alpha) = Lstr = 10(sup 38.6) (+/- 10(sup 0.1)) erg/ s (no other peaks are found in any of the LFs) accompanying a steepening of slope for LH(sub alpha) greater than Lstr This behavior is readily explicable via a physical model whose basic premises are: (a) the transition at LH(sub alpha) = Lstr marks a change from essentially ionization bounding at low luminosities to density bounding at higher values, (b) for this to occur the law relating stellar mass in massive star-forming clouds to the mass of the placental cloud must be such that the ionizing photon flux produced within the cloud is a function which rises more steeply than the mass of the cloud. Supporting evidence for the hypothesis of this transition is also presented: measurements of the central surface brightnesses of H II regions for LH(sub alpha) less than Lstr are proportional to L(sup 1/3, sub H(sub alpha)), expected for ionization bounding, but show a sharp trend to a steeper dependence for LH(sub alpha) greater than Lstr, and the observed relation between the internal turbulence velocity parameter, sigma, and the luminosity, L, at high luminosities, can be well explained if these regions are density bounded. If confirmed, the density-bounding hypothesis would have a number of interesting implications. It would imply that the density-bounded regions were the main sources of the photons which ionize the diffuse gas in disk galaxies. Our estimates, based on the hypothesis, indicate that these regions emit sufficient Lyman continuum not only to

  14. Evidence of liquid phase during laser-induced periodic surface structures formation induced by accumulative ultraviolet picosecond laser beam

    SciTech Connect

    Huynh, T. T. D.; Petit, A.; Semmar, N.

    2015-11-09

    Laser-induced periodic surface structures (LIPSS) were formed on Cu/Si or Cu/glass thin films using Nd:YAG laser beam (40 ps, 10 Hz, and 30 mJ/cm{sup 2}). The study of ablation threshold is always achieved over melting when the variation of the number of pulses increases from 1 to 1000. But the incubation effect is leading to reduce the threshold of melting as increasing the number of laser pulse. Also, real time reflectivity signals exhibit typical behavior to stress the formation of a liquid phase during the laser-processing regime and helps to determine the threshold of soft ablation. Atomic Force Microscopy (AFM) analyses have shown the topology of the micro-crater containing regular spikes with different height. Transmission Electron Microscopy (TEM) allows finally to show three distinguished zones in the close region of isolated protrusions. The central zone is a typical crystallized area of few nanometers surrounded by a mixed poly-crystalline and amorphous area. Finally, in the region far from the protrusion zone, Cu film shows an amorphous structure. The real time reflectivity, AFM, and HR-TEM analyses evidence the formation of a liquid phase during the LIPSS formation in the picosecond regime.

  15. Slip-rates along the Chaman fault: Implication for transient strain accumulation and strain partitioning along the western Indian plate margin

    NASA Astrophysics Data System (ADS)

    Ul-Hadi, Shams; Khan, Shuhab D.; Owen, Lewis A.; Khan, Abdul S.; Hedrick, Kathryn A.; Caffee, Marc W.

    2013-11-01

    The Chaman fault in Western Pakistan marks the western collision boundary between the Indian and Eurasian plates and connects the Makran subduction zone to the Himalayan convergence zone. Geomorphic-scale slip-rates along an active strand of the Chaman fault are added to the sporadic data set of this poorly investigated transform system. Field investigations coupled with high-resolution GeoEye-1 satellite data of an alluvial fan surface (Bostankaul alluvial fan) show ~ 1150 m left-lateral offset by the fault since the formation of the alluvial fan surface. A weighted mean 10Be exposure age of 34.8 ± 3 kyr for the Bostankaul alluvial surface yields a slip-rate of 33.3 ± 3.0 mm/yr. This rate agrees with the geologically defined slip-rates along the Chaman fault, but is approximately twice as large as that inferred from the decade-long global positioning system measurements of 18 ± 1 mm/yr. The contrast in geomorphic and geodetic slip-rates along the Chaman fault, like other major intra-continental strike-slip faults, has two major implications: 1) the geodetic rates might represent a period of reduced displacement as compared to the averaged Late Pleistocene rate because of transient variations in rates of elastic strain accumulation; or 2) strain partitioning within the plate boundary zone. While strain partitioning could be the reason of slip-rate variations within the western Indian plate boundary zone, transient strain accumulation could explain contrasting slip-rates along the Chaman fault at this stage in its poorly understood seismic cycle.

  16. Water and Brines on Mars: Current Evidence and Implications for MSL

    NASA Astrophysics Data System (ADS)

    Martínez, G. M.; Renno, N. O.

    2013-06-01

    Liquid water is a basic ingredient for life as we know it. Therefore, in order to understand the habitability of other planets we must first understand the behavior of water on them. Mars is the most Earth-like planet in the solar system and it has large reservoirs of H2O. Here, we review the current evidence for pure liquid water and brines on Mars, and discuss their implications for future and current missions such as the Mars Science Laboratory. Neither liquid water nor liquid brines are currently stable on the surface of Mars, but they could be present temporarily in a few areas of the planet. Pure liquid water is unlikely to be present, even temporarily, on the surface of Mars because evaporation into the extremely dry atmosphere would inhibit the formation of the liquid phase, where the temperature and pressure are high enough so that water would neither freeze nor boil. The exception to this is that monolayers of liquid water, referred to as undercooled liquid interfacial water, could exist on most of the Martian surface. In a few places liquid brines could exist temporarily on the surface because they could form at cryogenic temperatures, near ice or frost deposits where sublimation could be inhibited by the presence of nearly saturated air. Both liquid water and liquid brines might exist in the shallow subsurface because even a thin layer of soil forms an effective barrier against sublimation allowing pure liquid water to form sporadically in a few places, or liquid brines to form over longer periods of time in large portions of the planet. At greater depths, ice deposits could melt where the soil conductivity is low enough to blanket the deeper subsurface effectively. This could cause the formation of aquifers if the deeper soil is sufficiently permeable and an impermeable layer exists below the source of water. The fact that liquid brines and groundwater are likely to exist on Mars has important implications for geochemistry, glaciology, mineralogy

  17. Nitrogen starvation-induced accumulation of triacylglycerol in the green algae: evidence for a role for ROC40, a transcription factor involved in circadian rhythm.

    PubMed

    Goncalves, Elton C; Koh, Jin; Zhu, Ning; Yoo, Mi-Jeong; Chen, Sixue; Matsuo, Takuya; Johnson, Jodie V; Rathinasabapathi, Bala

    2016-03-01

    Microalgal triacylglycerol (TAG), a promising source of biofuel, is induced upon nitrogen starvation (-N), but the proteins and genes involved in this process are poorly known. We performed isobaric tagging for relative and absolute quantification (iTRAQ)-based quantitative proteomics to identify Chlorella proteins with modulated expression under short-term -N. Out of 1736 soluble proteins and 2187 membrane-associated proteins identified, 288 and 56, respectively, were differentially expressed under -N. Gene expression analysis on select genes confirmed the same direction of mRNA modulation for most proteins. The MYB-related transcription factor ROC40 was the most induced protein, with a 9.6-fold increase upon -N. In a previously generated Chlamydomonas mutant, gravimetric measurements of crude total lipids revealed that roc40 was impaired in its ability to increase the accumulation of TAG upon -N, and this phenotype was complemented when wild-type Roc40 was expressed. Results from radiotracer experiments were consistent with the roc40 mutant being comparable to the wild type in recycling membrane lipids to TAG but being impaired in additional de novo synthesis of TAG during -N stress. In this study we provide evidence to support the hypothesis that transcription factor ROC40 has a role in -N-induced lipid accumulation, and uncover multiple previously unknown proteins modulated by short-term -N in green algae. PMID:26920093

  18. Analysis of the accumulation of Pea enation mosaic virus genomes in seed tissues and lack of evidence for seed transmission in pea (Pisum sativum).

    PubMed

    Timmerman-Vaughan, Gail; Larsen, Richard; Murray, Sarah; McPhee, Kevin; Coyne, Clarice

    2009-11-01

    Pea enation mosaic virus (PEMV) is an important virus disease of pea. International movement of commercial pea cultivars and germplasm can be problematic due to uncertainty about seed transmission of the viruses responsible for the disease. Whether PEMV is seedborne was assessed by collecting developing seed from infected plants and determining the relative concentrations of the PEMV-1 and PEMV-2 viral genomes using quantitative real-time reverse-transcription polymerase chain reaction. The relative accumulation of PEMV-1 and PEMV-2 was approximately 1,240 and 13,000 times higher, respectively, in leaf than in embryo tissues. Accumulation of PEMV-1 and PEMV-2 RNA was also significantly higher in pod walls and seed coats than in cotyledons or embryo axes. No evidence was obtained for seed transmission of PEMV in pea. Although PEMV-1 and PEMV-2 genomic RNAs were found in developing seed, no PEMV symptoms were observed in the field on more than 50,000 plants from seed derived from PEMV-infected source plants. These data demonstrate that PEMV is seedborne in pea but do not support a previous report that PEMV is seed transmitted. Absence of seed transmission may result from the low abundance of PEMV viral genomes in embryo tissue.

  19. Project Hotspot: Linear accumulation rates of late Cenozoic basalt at Kimama, Idaho, and implications for crustal strain and subsidence rates of the central Snake River Plain

    NASA Astrophysics Data System (ADS)

    Rodgers, D. W.; Potter, K. E.; Shervais, J. W.; Champion, D. E.; Duncan, R. A.

    2013-12-01

    Project Hotspot's Kimama drill hole on the Snake River Plain, Idaho recovered a 1912 m thick section of basalt core that ranges in age from ~700 ka to at least 6.14 Ma, based on five 40Ar/39Ar analyses and twenty paleomagnetic age assignments. Fifty-four flow groups comprising 510 individual flows were defined, yielding an average recurrence interval of ~11,400 years between flows. Age-depth analysis indicate that, over thicknesses >150 m and age spans >500 k.y., accumulation rates were constant at 30 m/100 k.y. The existence and persistence of this linear accumulation rate for greater than 5 m.y. documents an external tectonic control on eruption dynamics. One conceptual model relates accumulation rates to horizontal crustal strain, such that far-field extension rate controls the periodicity of dikes that feed basalt flows. In this model, each of the 54 flow groups would have a deep-seated, relatively wide (1-10m) dike that branches upward into a network of narrow (10-100 cm) dikes feeding individual lava flows. Assuming an east-west lateral lava flow extent of up to 50 km, the Kimama data record a steady-state crustal strain rate of 10-9 to 10-10 y-1. This rate is comparable to modern, decadal strain rates measured with GPS in the adjacent Basin & Range province, but exceeds decadal strain rates of zero measured in the eastern Snake River Plain. Linear accumulation rates also provide insight into basalt subsidence history. In this model, the middle-upper crust subsides due to the added weight of lava flows, the added weight of mid-crustal sills/dikes, and thermal contraction in the wake of the Yellowstone hot spot. Isostatic compensation would occur in the (nearly) molten lower crust. Assuming constant surface elevation and a basalt density of 2.6 g/cm3, the lava flow weight would account for 87% of the burial through time, yielding a steady-state "tectonic" subsidence rate of 4 m/100 k.y. attributed to the driving forces of mid-crustal injection and/or thermal

  20. Accumulate-Repeat-Accumulate-Accumulate-Codes

    NASA Technical Reports Server (NTRS)

    Divsalar, Dariush; Dolinar, Sam; Thorpe, Jeremy

    2004-01-01

    Inspired by recently proposed Accumulate-Repeat-Accumulate (ARA) codes [15], in this paper we propose a channel coding scheme called Accumulate-Repeat-Accumulate-Accumulate (ARAA) codes. These codes can be seen as serial turbo-like codes or as a subclass of Low Density Parity Check (LDPC) codes, and they have a projected graph or protograph representation; this allows for a high-speed iterative decoder implementation using belief propagation. An ARAA code can be viewed as a precoded Repeat-and-Accumulate (RA) code with puncturing in concatenation with another accumulator, where simply an accumulator is chosen as the precoder; thus ARAA codes have a very fast encoder structure. Using density evolution on their associated protographs, we find examples of rate-lJ2 ARAA codes with maximum variable node degree 4 for which a minimum bit-SNR as low as 0.21 dB from the channel capacity limit can be achieved as the block size goes to infinity. Such a low threshold cannot be achieved by RA or Irregular RA (IRA) or unstructured irregular LDPC codes with the same constraint on the maximum variable node degree. Furthermore by puncturing the accumulators we can construct families of higher rate ARAA codes with thresholds that stay close to their respective channel capacity thresholds uniformly. Iterative decoding simulation results show comparable performance with the best-known LDPC codes but with very low error floor even at moderate block sizes.

  1. The recovery of pollen evidence from documents and its forensic implications.

    PubMed

    Morgan, R M; Davies, G; Balestri, F; Bull, P A

    2013-12-01

    Three experiments were undertaken to establish the potential for forensic palynological analysis in cases of suspected document fraud. The first study tested 6 different types of paper and 9 different types of ink (n=54) and it was established that the best retainer of particulates (in this case a proxy was used in the form of UV powder) was medium biro ink and Wove and Connoisseur paper. It was found that for the different paper types 42-52% of the particulates collected were found in the ink and thus both the paper and the ink are potentially valuable sources of trace evidence in a forensic investigation. The second study sought to address the differences in the spatial distribution of particulates on documents when writing took place before or after the paper was treated with UV particulates. Ninety-six observations were made for each piece of paper tested and it was found that when the writing took place after the particulates were applied to the paper; more particulates were retained on the paper in contrast to when the writing took place before the particulate treatment. The spatial distribution of particulates was also affected, with particulates being retained in the folds of the paper when the writing took place before particulate treatment in contrast to a more erratic pattern that emerged due to the pressure of the hand of the writer when the writing took place after the particulate treatment. The third study utilised lily (Lilium) pollen grains and the findings broadly concurred with the second study. The main difference identified was when the writing took place before the particulates were applied; when UV powder was used the particulates were retained in the folds of the paper whereas this pattern was not seen to the same degree when pollen grains were used due to their 'stickier' nature. Envelopes and the pen nibs were also found to be rich sources of pollen grains after the experiments were undertaken. These studies have implications for the

  2. The recovery of pollen evidence from documents and its forensic implications.

    PubMed

    Morgan, R M; Davies, G; Balestri, F; Bull, P A

    2013-12-01

    Three experiments were undertaken to establish the potential for forensic palynological analysis in cases of suspected document fraud. The first study tested 6 different types of paper and 9 different types of ink (n=54) and it was established that the best retainer of particulates (in this case a proxy was used in the form of UV powder) was medium biro ink and Wove and Connoisseur paper. It was found that for the different paper types 42-52% of the particulates collected were found in the ink and thus both the paper and the ink are potentially valuable sources of trace evidence in a forensic investigation. The second study sought to address the differences in the spatial distribution of particulates on documents when writing took place before or after the paper was treated with UV particulates. Ninety-six observations were made for each piece of paper tested and it was found that when the writing took place after the particulates were applied to the paper; more particulates were retained on the paper in contrast to when the writing took place before the particulate treatment. The spatial distribution of particulates was also affected, with particulates being retained in the folds of the paper when the writing took place before particulate treatment in contrast to a more erratic pattern that emerged due to the pressure of the hand of the writer when the writing took place after the particulate treatment. The third study utilised lily (Lilium) pollen grains and the findings broadly concurred with the second study. The main difference identified was when the writing took place before the particulates were applied; when UV powder was used the particulates were retained in the folds of the paper whereas this pattern was not seen to the same degree when pollen grains were used due to their 'stickier' nature. Envelopes and the pen nibs were also found to be rich sources of pollen grains after the experiments were undertaken. These studies have implications for the

  3. Lipid-lowering therapies, glucose control and incident diabetes: evidence, mechanisms and clinical implications.

    PubMed

    Zafrir, Barak; Jain, Mohit

    2014-08-01

    Lipid-lowering therapies constitute an essential part in the treatment and prevention of cardiovascular diseases and are consistently shown to reduce adverse cardiovascular outcomes in wide-scale populations. Recently, there is increased awareness of the possibility that lipid-lowering drugs may affect glucose control and insulin resistance. This phenomenon is reported in all classes of lipid-modifying agents, with differential effects of distinct drugs. Since the prevalence of metabolic syndrome and diabetes is rising, and lipid-modifying therapies are widely used to reduce the cardiovascular burden in these populations, it is of importance to examine the relationship between lipid-lowering drugs, glycemic control and incident diabetes. In the current review we discuss the evidence, ranging from experimental studies to randomized controlled clinical trials and meta-analyses, of how lipid-modifying therapies affect glycemic control and insulin sensitivity. Cumulative data suggest that both statins and niacin are associated with increased risk of impaired glucose control and development of new-onset diabetes, as opposed to bile-acid sequestrants which display concomitant moderate lipid and glucose lowering effects, and fibrates (particularly the pan-PPAR agonist bezafibrate) which may produce beneficial effects on glucose metabolism and insulin sensitivity. Ezetimibe is implied to ameliorate metabolic markers such as hepatic steatosis and insulin resistance, with yet little support from clinical trials, while fish oils which in experimental studies produce favorable effects on insulin sensitivity, although studied extensively, continue to show inconclusive effects on glucose homeostasis in patients with diabetes. Suggested mechanisms of how lipid-modifying agents affect glucose control and their clinical implications in this context, are summarized. PMID:24952127

  4. The impact of work environment on mood disorders and suicide: Evidence and implications

    PubMed Central

    Woo, Jong-Min; Postolache, Teodor T

    2008-01-01

    The purpose of this paper is to review the evidence estimating an impact of occupational factors on mood disorders and suicide, and the efficacy of interventions. This review is based on literature searches using Medline and Psych INFO from 1966 to 2007 (keywords: work stress, job insecurity, job strain, shift work, violence, occupational health, mood disorders, depression, and suicide). To establish the relationship between occupational variables and mood disorders, we focused on clinically significant disorders rather than depressive symptoms. During the last decade, prospective epidemiological studies have suggested a predictive association between the work environment and mood disorders. Recently, increasing numbers of clinical trials have shown favorable effect size of intervention and suggested preferable return-on-investment results. However, low awareness and social stigma still decrease workers access to treatment. Mental health professionals in conjunction with employers have to devise a creative system to make the quality care being offered more accessible to employees. In addition, further outcome data is needed to evaluate the benefit of managing mood disorders in the workplace, and to foster awareness of positive implications for employees, employers, their families, and the society at large. In addition, the work environment, with its chemical (e.g. chemosensory factors, pollutants), physical (e.g. lighting, noise, temperature, outdoor views and activities), biological (e.g., chronobiological factors, allergens, infectious agents), psychological (e.g. demand-control, effort-reward balance), social (e.g. cohesiveness, support), and organizational (e.g. leadership styles) component should meet minimal standards, and may improve with striving towards the optimum. PMID:18836547

  5. Evidence for a fundamental stellar upper mass limit from clustered star formation, and some implications therof

    NASA Astrophysics Data System (ADS)

    Kroupa, Pavel; Weidner, Carsten

    Theoretical considerations lead to the expectation that stars should not have masses larger than about m_{max*}=60-120M_⊙, while the observational evidence has been ambiguous. Only very recently has a physical stellar mass limit near 150M_⊙ emerged thanks to modern high-resolution observations of local star-burst clusters. But this limit does not appear to depend on metallicity, in contradiction to theory. Important uncertainties remain though. It is now also emerging that star-clusters limit the masses of their constituent stars, such that a well-defined relation between the mass of the most massive star in a cluster and the cluster mass, m_{max}=F(M_{ecl}) ≤ m_{max*}≈ 150M_⊙, exists. One rather startling finding is that the observational data strongly favour clusters being built-up by consecutively forming more-massive stars until the most massive stars terminate further star-formation. The relation also implies that composite populations, which consist of many star clusters, most of which may be dissolved, must have steeper composite IMFs than simple stellar populations such as are found in individual clusters. Thus, for example, 10^5 Taurus-Auriga star-forming groups, each with 20 stars, will ever only sample the IMF below about 1M_⊙. This IMF will therefore not be identical to the IMF of one cluster with 2×, 10^6 stars. The implication is that the star-formation history of a galaxy critically determines its integrated galaxial IMF and thus the total number of supernovae per star and its chemical enrichment history. Galaxy formation and evolution models that rely on an invariant IMF would be wrong.

  6. Accumulate-Repeat-Accumulate-Accumulate Codes

    NASA Technical Reports Server (NTRS)

    Divsalar, Dariush; Dolinar, Samuel; Thorpe, Jeremy

    2007-01-01

    Accumulate-repeat-accumulate-accumulate (ARAA) codes have been proposed, inspired by the recently proposed accumulate-repeat-accumulate (ARA) codes. These are error-correcting codes suitable for use in a variety of wireless data-communication systems that include noisy channels. ARAA codes can be regarded as serial turbolike codes or as a subclass of low-density parity-check (LDPC) codes, and, like ARA codes they have projected graph or protograph representations; these characteristics make it possible to design high-speed iterative decoders that utilize belief-propagation algorithms. The objective in proposing ARAA codes as a subclass of ARA codes was to enhance the error-floor performance of ARA codes while maintaining simple encoding structures and low maximum variable node degree.

  7. Evidence for gas accumulation beneath the surface crust driving cyclic rise and fall of the lava surface at Halema`uma`u, Kilauea Volcano

    NASA Astrophysics Data System (ADS)

    Patrick, M. R.; Orr, T. R.; Wilson, D.; Sutton, A. J.; Elias, T.; Fee, D.; Nadeau, P. A.

    2010-12-01

    The ongoing eruption in Halema`uma`u crater, at the summit of Kilauea Volcano, has surpassed the two-year mark and is characterized by lava lake activity in the vent. As of August 2010, the lava lake is about 70 m in diameter and 180 m below the rim of a narrow vent cavity. Although the explosive events that typified the first year of activity have abated, episodic rise and fall of the lava surface remains common. Cycles of rise and fall range from several minutes to eight hours in duration and are characterized by a quiescent rise phase and violent, gas-charged fall, spanning a height change of 20-30 m. Several models have been proposed to explain the cyclic rise and fall of lava surfaces at basaltic volcanoes, which in some cases is referred to as “gas pistoning”. In one model, episodic rise and fall is driven by the ascent of gas slugs from depth. In another, the cyclic behavior is driven by gas accumulation beneath the surface crust, with each cycle terminated by an abrupt failure of the crust, resulting in gas release. Seismic and infrasound data, as well as gas and webcam monitoring, at Halema`uma`u over the past two years strongly support the gas accumulation model, based on several lines of evidence. First, gas emission rates drop significantly below background levels during the rise phase, and increase dramatically during the fall phase, suggesting a process of gas buildup and release as opposed to slug flow. Second, the rise phases can last several hours, which is longer than reasonable slug ascent times. Third, the rise rate decreases over time, and in many cases plateaus, as the lava reaches its high stand, which is contrary to the exponential increase expected for gas slugs. Fourth, webcam video has captured numerous instances where rockfalls piercing the surface crust initiate gas release and lava level drop, suggestive of gas accumulation at shallow levels. Lastly, FTIR (Fourier Transform Infrared Spectroscopy) data reveal changes in gas

  8. [Marxism as a theoretical and methodological framework in collective health: implications for systematic review and synthesis of evidence].

    PubMed

    Soares, Cassia Baldini; Campos, Celia Maria Sivalli; Yonekura, Tatiana

    2013-12-01

    In this study, we discuss the integration in systematic reviews of research developed from a Marxist perspective of knowledge production and their results as evidence in healthcare. The study objectives are to review the assumptions of dialectical and historical materialism (DHM) and discuss the implications of dialectics for a literature review and the synthesis of evidence. DHM is a powerful framework for knowledge generation and transformation of policies and practices in healthcare. It assumes that social contradictions underlie the health-disease process, the fundamental theoretical construction in the field of collective health. Currently, we observe a considerable influence of the critical paradigm, of Marxist origin, in the construction of knowledge in health. Studies based on this critical paradigm incorporate complex methods, which are inherent to the guidelines of dialect, to identify the object and arrive at results that constitute evidence in healthcare. Systematic reviews should address the methodological difficulties associated with entirely integrating these results to healthcare.

  9. [Marxism as a theoretical and methodological framework in collective health: implications for systematic review and synthesis of evidence].

    PubMed

    Soares, Cassia Baldini; Campos, Celia Maria Sivalli; Yonekura, Tatiana

    2013-12-01

    In this study, we discuss the integration in systematic reviews of research developed from a Marxist perspective of knowledge production and their results as evidence in healthcare. The study objectives are to review the assumptions of dialectical and historical materialism (DHM) and discuss the implications of dialectics for a literature review and the synthesis of evidence. DHM is a powerful framework for knowledge generation and transformation of policies and practices in healthcare. It assumes that social contradictions underlie the health-disease process, the fundamental theoretical construction in the field of collective health. Currently, we observe a considerable influence of the critical paradigm, of Marxist origin, in the construction of knowledge in health. Studies based on this critical paradigm incorporate complex methods, which are inherent to the guidelines of dialect, to identify the object and arrive at results that constitute evidence in healthcare. Systematic reviews should address the methodological difficulties associated with entirely integrating these results to healthcare. PMID:24626368

  10. Does Missing Classes Decelerate Student Exam Performance Progress? Empirical Evidence and Policy Implications

    ERIC Educational Resources Information Center

    Lin, Tin-Chun

    2014-01-01

    A total of 389 business students in undergraduate introductory microeconomics classes in spring 2007, 2009, and 2011, and fall 2012 participated in an exam performance progress study. Empirical evidence suggested that missing classes decelerates and hampers high-performing students' exam performance progress. Nevertheless, the evidence does…

  11. Evidence of Second-Order Factor Structure in a Diagnostic Problem Space: Implications for Medical Education.

    ERIC Educational Resources Information Center

    Papa, Frank J.; And Others

    1997-01-01

    Chest pain was identified as a specific medical problem space, and disease classes were modeled to define it. Results from a test taken by 628 medical residents indicate a second-order factor structure that suggests that chest pain is a multidimensional problem space. Implications for medical education are discussed. (SLD)

  12. Hierarchical Structure and General Factor Saturation of the Anxiety Sensitivity Index: Evidence and Implications.

    ERIC Educational Resources Information Center

    Zinbarg, Richard E.; Barlow, David H.; Brown, Timothy A.

    1997-01-01

    A hierarchical factor model of the Anxiety Sensitivity Index (ASI) (S. Reiss and others, 1986) was evaluated with 432 psychiatric outpatients and 32 people with no mental disorder. Results support a hierarchical factor structure of three lower order factors and one higher order factor. Implications for the assessment of anxiety sensitivity are…

  13. Sound Foundations: A Review of the Research Evidence on Quality of Early Childhood Education and Care for Children under Three. Implications for Policy and Practice

    ERIC Educational Resources Information Center

    Mathers, Sandra; Eisenstadt, Naomi; Sylva, Kathy; Soukakou, Elena; Ereky-Stevens, Katharina

    2014-01-01

    This report provides a literature review of the evidence on the quality of early childhood education and care for children under three. It considers the implications for policy and practice, particularly for the Government's programme of free early years provision for disadvantaged two year-olds. The review of the research evidence identified four…

  14. COMPARING RATING PARADIGMS FOR EVIDENCE-BASED PROGRAM REGISTERS IN BEHAVIORAL HEALTH: EVIDENTIARY CRITERIA AND IMPLICATIONS FOR ASSESSING PROGRAMS

    PubMed Central

    Means, Stephanie N.; Magura, Stephen; Burkhardt, Jason T.; Schröter, Daniela C.; Coryn, Chris L.S.

    2014-01-01

    Decision makers need timely and credible information about the effectiveness of behavioral health interventions. Online evidence-based program registers (EBPRs) have been developed to address this need. However, the methods by which these registers determine programs and practices as being “evidence-based” has not been investigated in detail. This paper examines the evidentiary criteria EBPRs use to rate programs and the implications for how different registers rate the same programs. Although the registers tend to employ a standard Campbellian hierarchy of evidence to assess evaluation results, there is also considerable disagreement among the registers about what constitutes an adequate research design and sufficient data for designating a program as evidence-based. Additionally, differences exist in how registers report findings of “no effect,” which may deprive users of important information. Of all programs on the 15 registers that rate individual programs, 79% appear on only one register. Among a random sample of 100 programs rated by more than one register, 42% were inconsistently rated by the multiple registers to some degree. PMID:25450778

  15. Comparing rating paradigms for evidence-based program registers in behavioral health: evidentiary criteria and implications for assessing programs.

    PubMed

    Means, Stephanie N; Magura, Stephen; Burkhardt, Jason T; Schröter, Daniela C; Coryn, Chris L S

    2015-02-01

    Decision makers need timely and credible information about the effectiveness of behavioral health interventions. Online evidence-based program registers (EBPRs) have been developed to address this need. However, the methods by which these registers determine programs and practices as being “evidence-based” has not been investigated in detail. This paper examines the evidentiary criteria EBPRs use to rate programs and the implications for how different registers rate the same programs. Although the registers tend to employ a standard Campbellian hierarchy of evidence to assess evaluation results, there is also considerable disagreement among the registers about what constitutes an adequate research design and sufficient data for designating a program as evidence-based. Additionally, differences exist in how registers report findings of “no effect,” which may deprive users of important information. Of all programs on the 15 registers that rate individual programs, 79% appear on only one register. Among a random sample of 100 programs rated by more than one register, 42% were inconsistently rated by the multiple registers to some degree.

  16. Physician Perspectives on Comparative Effectiveness Research: Implications for Practice-based Evidence.

    PubMed

    Pierce, Beverly A; Chesney, Margaret A; Witt, Claudia M; Berman, Brian M

    2012-09-01

    Comparative effectiveness research (CER) is defined by the Institute of Medicine as "the generation and synthesis of evidence that compares the benefits and harms of alternative methods to prevent, diagnose, treat, and monitor a clinical condition or to improve the delivery of care." The goal of CER is to provide timely, useful evidence to healthcare decision makers including physicians, patients, policymakers, and payers. A prime focus for the use of CER evidence is the interaction between physician and patient. Physicians in primary practice are critical to the success of the CER enterprise. A 2009 survey suggests, however, that physician attitudes toward CER may be mixed-somewhat positive toward the potential for patient care improvement, yet negative toward potential restriction on physician freedom of practice. CER methods and goals closely parallel those of practice-based research, an important movement in family medicine in the United States since the 1970s. This article addresses apparent physician ambivalence toward CER and makes a case for family medicine engagement in CER to produce useful practice-based evidence. Such an effort has potential to expand care options through personalized medicine, individualized guidelines, focus on patient preferences and patient-reported outcomes, and study of complex therapeutic interventions, such as integrative care. Academic medical researchers will need to collaborate with experienced family physicians to identify significant practice-based research questions and design meaningful studies. Such collaborations would shape CER to produce high-quality practice-based evidence to inform family and community medicine.

  17. The many meanings of evidence: implications for the translational science agenda in healthcare.

    PubMed

    Harvey, Gill

    2013-09-01

    Health systems across the world are concerned with the quality and safety of patient care. This includes investing in research and development to progress advances in the treatment and management of individuals and healthcare organisations. The concept of evidence- based healthcare has gained increasing currency over the last two decades; yet questions persist about the time it takes for new research evidence to find its way into day to day healthcare decision-making. This paper explores the reasons for this apparent gap between research and healthcare practice, management and policy-making. In particular, the paper argues that different meanings attached to the word 'evidence' fundamentally influence the way in which the research-practice gap is conceptualised and subsequent strategies that are implemented to increase the uptake of research.

  18. Thunderstorm asthma: an overview of the evidence base and implications for public health advice.

    PubMed

    Dabrera, G; Murray, V; Emberlin, J; Ayres, J G; Collier, C; Clewlow, Y; Sachon, P

    2013-03-01

    Thunderstorm asthma is a term used to describe an observed increase in acute bronchospasm cases following the occurrence of thunderstorms in the local vicinity. The roles of accompanying meteorological features and aeroallergens, such as pollen grains and fungal spores, have been studied in an effort to explain why thunderstorm asthma does not accompany all thunderstorms. Despite published evidence being limited and highly variable in quality due to thunderstorm asthma being a rare event, this article reviews this evidence in relation to the role of aeroallergens, meteorological features and the impact of thunderstorm asthma on health services. This review has found that several thunderstorm asthma events have had significant impacts on individuals' health and health services with a range of different aeroallergens identified. This review also makes recommendations for future public health advice relating to thunderstorm asthma on the basis of this identified evidence. PMID:23275386

  19. Thunderstorm asthma: an overview of the evidence base and implications for public health advice.

    PubMed

    Dabrera, G; Murray, V; Emberlin, J; Ayres, J G; Collier, C; Clewlow, Y; Sachon, P

    2013-03-01

    Thunderstorm asthma is a term used to describe an observed increase in acute bronchospasm cases following the occurrence of thunderstorms in the local vicinity. The roles of accompanying meteorological features and aeroallergens, such as pollen grains and fungal spores, have been studied in an effort to explain why thunderstorm asthma does not accompany all thunderstorms. Despite published evidence being limited and highly variable in quality due to thunderstorm asthma being a rare event, this article reviews this evidence in relation to the role of aeroallergens, meteorological features and the impact of thunderstorm asthma on health services. This review has found that several thunderstorm asthma events have had significant impacts on individuals' health and health services with a range of different aeroallergens identified. This review also makes recommendations for future public health advice relating to thunderstorm asthma on the basis of this identified evidence.

  20. Evidence Based Surgery: How Difficult is the Implication in Routine Practice?

    PubMed Central

    Maheshwari, Gaurav; Maheshwari, Namrata

    2012-01-01

    Surgery as a discipline has perhaps been slower than other specialties to embrace evidence based principles. Today, surgeons all over Asia are prepared to challenge the dogma of yesterday. Surgical science which rests on a strong foundation of laboratory and clinical research can now be broadened to include the armamentarium of evidence based practice to advance surgical knowledge. The sheer volume of easily accessed information creates a new challenge. This article discusses keeping up with new information and finding the best available answers to specific questions amidst all the other information. PMID:22359733

  1. Legal and Technical Implications of Collecting Wireless Data as an Evidence Source

    NASA Astrophysics Data System (ADS)

    Turnbull, Benjamin; Osborne, Grant; Simon, Matthew

    The collection of digital devices for forensic analysis is an area that requires constant revision. New technologies and connectivity options change what devices are able to hold electronic evidence and also the methods needed to secure it. This work focuses on the development of an 802.11-based wireless networking (Wi-Fi) forensic analysis tool that can aid in the identification and collection of evidence by identifying the presence of wireless networks and the devices to which they are attached. Specifically, this paper seeks to discuss the potential legal and technical challenges faced in the development of a wireless forensic tool.

  2. Palynological indications for elevated microbial primary productivity during the Early Toarcian Anoxic Event: Implications for organic-carbon accumulation and the interpretation of δ13C-trends

    NASA Astrophysics Data System (ADS)

    Houben, A. J. P.; Goldberg, T.; Janssen, N. M. M.; Nelskamp, S.; Verreussel, R.

    2015-12-01

    The Early Toarcian Oceanic Anoxic Event (T-OAE, ~182 Ma ago) represents an episode of organic-rich deposition that was accompanied by a substantial (up to 7‰) negative carbon-isotope excursion (CIE), suggesting a perturbation in the carbon cycle likely driven by the addition of "light" carbon to the ocean-atmosphere system. Paired δ13Corg-ratios and hydrogen-indices provide evidence for major changes in organic-matter sourcing which quantitatively affect CIE-magnitude. Underpinning the relationship between this carbon-cycle perturbation, ocean anoxia and primary productivity feedbacks thus remains a major challenge. We here present palynological- and organic-matter analysis data from outcrop sections in Yorkshire (UK) and three drill-cores from the Netherlands. In addition, elemental ratios and iron speciation data aid to constrain bottom-water oxygenation and euxinia. Stratigraphic calibrations were achieved with high-resolution δ13Corg-data. The iron-speciation and trace-element data indicate that persistent euxinic bottom-water conditions incept at the base of- and remarkably persist after the T-OAE. By employing extremely careful palynological preparation and UV-fluorescence microscopy, we assessed changes in phytoplankton communities and organic-matter types. At the base of the T-OAE a major increase in abundance of prasinophycean vegetative cysts indicates chemocline shoaling into the photic zone. During the T-OAE, all localities are characterized by organic-matter associations dominated by dense Structureless Organic Matter (SOM) that contain abundant characteristic sphaerical palynomorphs.These results confirm changes in organic-carbon sourcing, which exaggerate the magnitude of the CIE. The palynological and organic-matter data indicate that primary productivity did not collapse and that TOC-accumulations were not merely an effect of inhibited remineralization duirng anoxia. In contrast, we present a scenario in which cyanobacterial anoxygenic

  3. Evidence-Based Fitness Promotion in an Afterschool Setting: Implementation Fidelity and Its Policy Implications

    ERIC Educational Resources Information Center

    Thaw, Jean M.; Villa, Manuela; Reitman, David; DeLucia, Christian; Gonzalez, Vanessa; Hanson, K. Lori

    2014-01-01

    Little is known about how the adoption of evidence-based physical activity (PA) curricula by out-of-school time (OST) programs affects children's physical fitness, and there are no clear guidelines of what constitutes reasonable gains given the types of PA instruction currently offered in these programs. Using a three-wave,…

  4. Senescence in natural populations of animals: widespread evidence and its implications for bio-gerontology.

    PubMed

    Nussey, Daniel H; Froy, Hannah; Lemaitre, Jean-François; Gaillard, Jean-Michel; Austad, Steve N

    2013-01-01

    That senescence is rarely, if ever, observed in natural populations is an oft-quoted fallacy within bio-gerontology. We identify the roots of this fallacy in the otherwise seminal works of Medawar and Comfort, and explain that under antagonistic pleiotropy or disposable soma explanations for the evolution of senescence there is no reason why senescence cannot evolve to be manifest within the life expectancies of wild organisms. The recent emergence of long-term field studies presents irrefutable evidence that senescence is commonly detected in nature. We found such evidence in 175 different animal species from 340 separate studies. Although the bulk of this evidence comes from birds and mammals, we also found evidence for senescence in other vertebrates and insects. We describe how high-quality longitudinal field data allow us to test evolutionary explanations for differences in senescence between the sexes and among traits and individuals. Recent studies indicate that genes, prior environment and investment in growth and reproduction influence aging rates in the wild. We argue that - with the fallacy that wild animals do not senesce finally dead and buried - collaborations between bio-gerontologists and field biologists can begin to test the ecological generality of purportedly 'public' mechanisms regulating aging in laboratory models.

  5. The role of intact family childhood on women's earnings capacity: implications for evidence-based practices.

    PubMed

    Caputo, Richard K; Mason, Susan E

    2009-07-01

    This article examines the complexities of working with an evidence-based model to design intervention strategies benefiting individuals and families. It addresses the question, to what extent should the evidence of economic advantage for female children raised in two-parent families influence social work support for practices and policies that encourage marriage? The article reviews current research findings indicating benefits of two-parent families on children's well-being and contemporary policy prescriptions promoting marriage. It presents findings of the authors' study which considers the effects of being raised in an intact family on the economic future of young women. The evidence presented in the literature and found in our own study suggests that promotion of marriage may be a sound intervention strategy for parents interested in the economic advantages for their children later in life. For others, it may be the wrong choice based on women's personal circumstances. The association between early family structure and future well-being is further complicated by large gaps in the data on cultural and family diversity. Suggestions for social work practice are based on the synthesis of the evidence-based model and the values of the profession. PMID:20183676

  6. Senescence in natural populations of animals: Widespread evidence and its implications for bio-gerontology

    PubMed Central

    Nussey, Daniel H.; Froy, Hannah; Lemaitre, Jean-François; Gaillard, Jean-Michel; Austad, Steve N.

    2014-01-01

    That senescence is rarely, if ever, observed in natural populations is an oft-quoted fallacy within bio-gerontology. We identify the roots of this fallacy in the otherwise seminal works of Medawar and Comfort, and explain that under antagonistic pleiotropy or disposable soma explanations for the evolution of senescence there is no reason why senescence cannot evolve to be manifest within the life expectancies of wild organisms. The recent emergence of long-term field studies presents irrefutable evidence that senescence is commonly detected in nature. We found such evidence in 175 different animal species from 340 separate studies. Although the bulk of this evidence comes from birds and mammals, we also found evidence for senescence in other vertebrates and insects. We describe how high-quality longitudinal field data allow us to test evolutionary explanations for differences in senescence between the sexes and among traits and individuals. Recent studies indicate that genes, prior environment and investment in growth and reproduction influence aging rates in the wild. We argue that – with the fallacy that wild animals do not senesce finally dead and buried – collaborations between bio-gerontologists and field biologists can begin to test the ecological generality of purportedly ‘public’ mechanisms regulating aging in laboratory models. PMID:22884974

  7. Implications of Neuroscientific Evidence for the Cognitive Models of Post-Traumatic Stress Disorder

    ERIC Educational Resources Information Center

    Cruwys, Tegan; O'Kearney, Richard

    2008-01-01

    Brewin's dual representation theory, Ehlers and Clark's cognitive appraisal model, and Dalgleish's schematic, propositional, analogue and associative representational systems model are considered in the light of recent evidence on the neural substrates of post-traumatic stress disorder (PTSD). The models' proposals about the cognitive mechanism of…

  8. Evidence-Based Counseling Interventions with Children of Divorce: Implications for Elementary School Counselors

    ERIC Educational Resources Information Center

    Connolly, Marianne E.; Green, Eric J.

    2009-01-01

    Parental divorce has become increasingly common for large numbers of families in schools (Lamden, King, & Goldman, 2002). This article addresses the effects of divorce on children and protective factors supporting their adjustment. Evidence-based interventions for children of divorce in elementary school counseling programs are discussed.…

  9. Weighing the Evidence for Psychotherapy Equivalence: Implications for Research and Practice

    ERIC Educational Resources Information Center

    Westmacott, Robin; Hunsley, John

    2007-01-01

    In the past two decades, numerous meta-analyses have been published that examine the question of psychotherapy equivalence. Hunsley and Di Giulio (2002) critically reviewed this literature and concluded that there was abundant evidence that the Dodo bird verdict of equivalence across psychotherapies is false. In this article, we summarize and…

  10. Etiology of impaired selective motor control: emerging evidence and its implications for research and treatment in cerebral palsy.

    PubMed

    Cahill-Rowley, Katelyn; Rose, Jessica

    2014-06-01

    Selective motor control (SMC) impairment involves movement patterns dominated by flexor or extensor synergies that interfere with functional movements in children with cerebral palsy (CP). Emerging evidence on neural correlates of impaired SMC has important implications for etiology and for the treatment for children with CP. Early evidence on the microstructure of brain white matter assessed with diffusion tensor imaging in adult patients after stroke suggests that the rubrospinal tract may compensate for injury to the corticospinal tract. Furthermore, the observed changes on diffusion tensor imaging corresponded to the degree of SMC impairment. The rubrospinal tract may provide imperfect compensation in response to corticospinal tract injury, resulting in diminished SMC. Cortical mapping evidence in stroke patients indicates that loss of SMC is also associated with increased overlap of joint representation in the sensorimotor cortices. The severity of SMC impairment can be assessed with the recently developed Selective Control Assessment of the Lower Extremity, a validated observation-based measure designed for children with spastic CP. Recent advances in neuroimaging and assessment of SMC provide an opportunity to better understand the etiology and impact of impaired SMC, which may ultimately guide strategic treatment for children with CP.

  11. Evidence for scripts in semantic dementia: Implications for theories of semantic memory.

    PubMed

    Funnell, E

    2001-06-01

    This paper presents evidence that the breakdown of semantic memory in semantic dementia reveals the influence of two properties of script theory (Schank, 1982; Schank & Abelson, 1977). First, the physical and personal context of specific scripts supports meaning for words, objects, and locations that are involved in the script. Second, meaning is updated or transformed by a dynamic memory system that learns continuously from personal experience. In severe cases, semantic dementia exposes the basic level of this learning system from which all knowledge normally develops. It will be argued that the evidence supports a theory of semantic memory that represents meaning in a continuum of levels of meaning from the most specific and context-bound to the most generalisable and context-free. This contrasts with current theories of semantic memory that represent meaning as a collection of abstracted properties entirely removed from the context of events and activities. PMID:20945219

  12. Impact of organizational change on organizational culture: implications for introducing evidence-based practice.

    PubMed

    Austin, Michael J; Claassen, Jennette

    2008-01-01

    Evidence-based practice (EBP) seeks to integrate the expertise of individual practitioners with the best available evidence within the context of the values and expectations of clients. Prior to implementing EBP, it is important to understand the significance that organizational change and organizational culture play. This article seeks to explore the literature associated with both organizational change and organizational culture. The analysis of organizational culture and change draw upon findings from both the private, for-profit sector, and the public, non-profit field. It is divided into four sections: organizational change and innovation, organizational culture, managing organizational culture and change, and finally, applying the findings to the implementation of EBP. While the audience for this analysis is managers in public and nonprofit human service organizations who are considering implementing EBP into their work environment, it is not intended to provide a "how to" guide, but rather a framework for critical thinking.

  13. Impact of organizational change on organizational culture: implications for introducing evidence-based practice.

    PubMed

    Austin, Michael J; Claassen, Jennette

    2008-01-01

    Evidence-based practice (EBP) seeks to integrate the expertise of individual practitioners with the best available evidence within the context of the values and expectations of clients. Prior to implementing EBP, it is important to understand the significance that organizational change and organizational culture play. This article seeks to explore the literature associated with both organizational change and organizational culture. The analysis of organizational culture and change draw upon findings from both the private, for-profit sector, and the public, non-profit field. It is divided into four sections: organizational change and innovation, organizational culture, managing organizational culture and change, and finally, applying the findings to the implementation of EBP. While the audience for this analysis is managers in public and nonprofit human service organizations who are considering implementing EBP into their work environment, it is not intended to provide a "how to" guide, but rather a framework for critical thinking. PMID:19064453

  14. Comparative clinical trials and the changing marketplace for oral care: innovation, evidence and implications.

    PubMed

    Gerlach, Robert W; Biesbrock, Aaron R

    2002-09-01

    The development of a trayless bleaching system (Crest Whitestrips) and a novel battery-powered toothbrush (Crest SpinBrush) has fueled growth in the bleaching and power toothbrush markets. Beyond offering convenient, low-cost options for patients, the effectiveness of each product is supported by a robust clinical program. New comparative research involving these products expands evidence on the clinical meaningfulness of the benefits of this whitening system and powered toothbrush for patient care. PMID:12512984

  15. Patients’ expectations of acute low back pain management: implications for evidence uptake

    PubMed Central

    2013-01-01

    Background In many countries, general practitioner (GP) care of acute low back pain often does not adhere to evidence-based clinical guidelines. There has been little exploration of this deviation from evidence-based care from the patients’ perspective, particularly in relation to patients’ care expectations. The aim of this study was to explore the care expectations in patients who present to their GP with acute low back pain, influences on expectation development, and congruence of these expectations with clinical guideline recommendations. Methods Qualitative study in an inner urban general practice in Brisbane, Australia. Semi-structured interviews were conducted with 11 patients who presented to their GP with acute low back pain. Results Patients had a biomechanical understanding of back pain, how it should be tested and treated, and a poor understanding of its natural history. Most expected x-rays, believing they were necessary to identify the “cause of the pain” without belief of any downsides to x-rays. Patients’ expectations were primarily influenced by the experiences of family and friends, their own previous experiences of low back pain care, and comments from other health professionals they were consulting. The GP-patient relationship was important in influencing patient satisfaction of care provided. Most patient expectations, and some of the care that they reported receiving, were incongruent with guideline recommendations. Conclusions A biomechanical approach to management rather than an awareness of empirical evidence was evident in patients’ expectations. Communication and education by the GP that includes specifically enquiring about patients’ expectations, provides an opportunity to correct misperceptions, explain acute low back pain natural history, and the rationale for test and treatment recommendations. PMID:23297840

  16. Short sleep duration and dietary intake: epidemiologic evidence, mechanisms, and health implications.

    PubMed

    Dashti, Hassan S; Scheer, Frank Ajl; Jacques, Paul F; Lamon-Fava, Stefania; Ordovás, José M

    2015-11-01

    Links between short sleep duration and obesity, type 2 diabetes, hypertension, and cardiovascular disease may be mediated through changes in dietary intake. This review provides an overview of recent epidemiologic studies on the relations between habitual short sleep duration and dietary intake in adults from 16 cross-sectional studies. The studies have observed consistent associations between short sleep duration and higher total energy intake and higher total fat intake, and limited evidence for lower fruit intake, and lower quality diets. Evidence also suggests that short sleepers may have irregular eating behavior deviating from the traditional 3 meals/d to fewer main meals and more frequent, smaller, energy-dense, and highly palatable snacks at night. Although the impact of short sleep duration on dietary intake tends to be small, if chronic, it may contribute to an increased risk of obesity and related chronic disease. Mechanisms mediating the associations between sleep duration and dietary intake are likely to be multifactorial and include differences in the appetite-related hormones leptin and ghrelin, hedonic pathways, extended hours for intake, and altered time of intake. Taking into account these epidemiologic relations and the evidence for causal relations between sleep loss and metabolism and cardiovascular function, health promotion strategies should emphasize improved sleep as an additional factor in health and weight management. Moreover, future sleep interventions in controlled studies and sleep extension trials in chronic short sleepers are imperative for establishing whether there is a causal relation between short sleep duration and changes in dietary intake.

  17. Short sleep duration and dietary intake: epidemiologic evidence, mechanisms, and health implications.

    PubMed

    Dashti, Hassan S; Scheer, Frank Ajl; Jacques, Paul F; Lamon-Fava, Stefania; Ordovás, José M

    2015-11-01

    Links between short sleep duration and obesity, type 2 diabetes, hypertension, and cardiovascular disease may be mediated through changes in dietary intake. This review provides an overview of recent epidemiologic studies on the relations between habitual short sleep duration and dietary intake in adults from 16 cross-sectional studies. The studies have observed consistent associations between short sleep duration and higher total energy intake and higher total fat intake, and limited evidence for lower fruit intake, and lower quality diets. Evidence also suggests that short sleepers may have irregular eating behavior deviating from the traditional 3 meals/d to fewer main meals and more frequent, smaller, energy-dense, and highly palatable snacks at night. Although the impact of short sleep duration on dietary intake tends to be small, if chronic, it may contribute to an increased risk of obesity and related chronic disease. Mechanisms mediating the associations between sleep duration and dietary intake are likely to be multifactorial and include differences in the appetite-related hormones leptin and ghrelin, hedonic pathways, extended hours for intake, and altered time of intake. Taking into account these epidemiologic relations and the evidence for causal relations between sleep loss and metabolism and cardiovascular function, health promotion strategies should emphasize improved sleep as an additional factor in health and weight management. Moreover, future sleep interventions in controlled studies and sleep extension trials in chronic short sleepers are imperative for establishing whether there is a causal relation between short sleep duration and changes in dietary intake. PMID:26567190

  18. Health Consequences of Uninsurance among Adults in the United States: Recent Evidence and Implications

    PubMed Central

    McWilliams, J Michael

    2009-01-01

    Context: Uninsured adults have less access to recommended care, receive poorer quality of care, and experience worse health outcomes than insured adults do. The potential health benefits of expanding insurance coverage for these adults may provide a strong rationale for reform. However, evidence of the adverse health effects of uninsurance has been largely based on observational studies with designs that do not support causal conclusions. Although recent research using more rigorous methods may offer a better understanding of this important subject, it has not been comprehensively reviewed. Methods: The clinical and economic literature since 2002 was systematically searched. New research contributions were reviewed and evaluated based on their methodological strength. Because the effectiveness of medical care varies considerably by clinical risk and across conditions, the consistency of study findings with clinical expectations was considered in their interpretation. Updated conclusions were formulated from the current body of research. Findings: The quality of research has improved significantly, as investigators have employed quasi-experimental designs with increasing frequency to address limitations of earlier research. Recent studies have found consistently positive and often significant effects of health insurance coverage on health across a range of outcomes. In particular, significant benefits of coverage have now been robustly demonstrated for adults with acute or chronic conditions for which there are effective treatments. Conclusions: Based on the evidence to date, the health consequences of uninsurance are real, vary in magnitude in a clinically consistent manner, strengthen the argument for universal coverage in the United States, and underscore the importance of evidence-based determinations in providing health care to a diverse population of adults. PMID:19523125

  19. Can universal pre-kindergarten programs improve population health and longevity? Mechanisms, evidence, and policy implications.

    PubMed

    Muennig, Peter

    2015-02-01

    Recent research has found that children who attended pre-kindergarten programs in childhood were more likely to be healthy as adults. One intuitive way of improving population health and longevity may therefore be to invest in pre-kindergarten programs. However, much of the research linking pre-kindergarten programs to health is very recent and has not been synthesized. In this paper, I review the mechanisms linking pre-kindergarten programs in childhood to adult longevity, and the experimental evidence backing up these linkages. I conclude with a critical exploration of whether investments in pre-kindergarten programs could also serve as investments in public health.

  20. Population ageing and its implications on aggregate health care demand: empirical evidence from 22 OECD countries.

    PubMed

    Palangkaraya, Alfons; Yong, Jongsay

    2009-12-01

    Recent evidence indicates that the relationship between age and health care expenditure is not as straightforward as it appears. In fact, micro-level studies find that time to death, rather than ageing, is possibly the main driver of the escalating health care costs in developed countries. Unfortunately, the evidence at the macro level is less clear and often depends on the specification of the empirical model used. We use an aggregate demand framework to assess whether health expenditure is more likely to be driven by ageing per se or proximity to death. Using panel data from 22 OECD countries from the first half of the 1990s, we find population ageing to be negatively correlated with health expenditure once proximity to death is accounted for. This suggests that the effects of ageing on health expenditure growth might be overstated while the effects of the high costs of medical care at the end of life are potentially underestimated. With respect to the latter, our finding highlights the importance of long-term and hospice care management. An expanded long-term care program may not only improve patient welfare, but also reduce costs of care by reducing the duration of hospital care for terminally ill patients. If expensive medical treatment for patients near the end of life can be controlled for, health expenditure growth resulting from population ageing is unlikely to present a most serious problem.

  1. Executive Summary of Hormonal Physiology of Childbearing: Evidence and Implications for Women, Babies, and Maternity Care.

    PubMed

    Buckley, Sarah J

    2015-01-01

    This report synthesizes evidence about innate hormonally mediated physiologic processes in women and fetuses/newborns during childbearing, and possible impacts of common maternity care practices and interventions on these processes, focusing on four hormone systems that are consequential for childbearing. Core hormonal physiology principles reveal profound interconnections between mothers and babies, among hormone systems, and from pregnancy through to the postpartum and newborn periods. Overall, consistent and coherent evidence from physiologic understandings and human and animal studies finds that the innate hormonal physiology of childbearing has significant benefits for mothers and babies. Such hormonally-mediated benefits may extend into the future through optimization of breastfeeding and maternal-infant attachment. A growing body of research finds that common maternity care interventions may disturb hormonal processes, reduce their benefits, and create new challenges. Developmental and epigenetic effects are biologically plausible but poorly studied. The perspective of hormonal physiology adds new considerations for benefit-harm assessments in maternity care, and suggests new research priorities, including consistently measuring crucial hormonally mediated outcomes that are frequently overlooked. Current understanding suggests that safely avoiding unneeded maternity care interventions would be wise, as supported by the Precautionary Principle. Promoting, supporting, and protecting physiologic childbearing, as far as safely possible in each situation, is a low-technology health and wellness approach to the care of childbearing women and their fetuses/newborns that is applicable in almost all maternity care settings. PMID:26834435

  2. Executive Summary of Hormonal Physiology of Childbearing: Evidence and Implications for Women, Babies, and Maternity Care

    PubMed Central

    Buckley, Sarah J.

    2015-01-01

    ABSTRACT This report synthesizes evidence about innate hormonally mediated physiologic processes in women and fetuses/newborns during childbearing, and possible impacts of common maternity care practices and interventions on these processes, focusing on four hormone systems that are consequential for childbearing. Core hormonal physiology principles reveal profound interconnections between mothers and babies, among hormone systems, and from pregnancy through to the postpartum and newborn periods. Overall, consistent and coherent evidence from physiologic understandings and human and animal studies finds that the innate hormonal physiology of childbearing has significant benefits for mothers and babies. Such hormonally-mediated benefits may extend into the future through optimization of breastfeeding and maternal-infant attachment. A growing body of research finds that common maternity care interventions may disturb hormonal processes, reduce their benefits, and create new challenges. Developmental and epigenetic effects are biologically plausible but poorly studied. The perspective of hormonal physiology adds new considerations for benefit-harm assessments in maternity care, and suggests new research priorities, including consistently measuring crucial hormonally mediated outcomes that are frequently overlooked. Current understanding suggests that safely avoiding unneeded maternity care interventions would be wise, as supported by the Precautionary Principle. Promoting, supporting, and protecting physiologic childbearing, as far as safely possible in each situation, is a low-technology health and wellness approach to the care of childbearing women and their fetuses/newborns that is applicable in almost all maternity care settings. PMID:26834435

  3. The multifocality of bronchioloalveolar lung carcinoma: evidence and implications of a multiclonal origin.

    PubMed

    Barsky, S H; Grossman, D A; Ho, J; Holmes, E C

    1994-08-01

    Bronchioloalveolar lung carcinoma (BAC) is a unique type of lung cancer with distinguishing pathologic, biologic, epidemiologic, and perhaps etiologic features that set it apart from all other forms of lung cancer, including general adenocarcinoma, into which it is traditionally grouped. Recent studies at our institution have demonstrated a near exponential increase in BAC cases with 25% showing evidence of multifocality. Although some theories suggest that this multifocality is caused by intrapulmonary aerosol/aspiration or lymphatic spread, this study provides evidence for multiclonality as the basis for some cases of multifocal BAC by exploiting a novel strategy for clonality determinations that involves polymerase chain reaction amplification of a 511-base pair region located within the first intron of the human hypoxanthine phosphoribosyltransferase gene, a site that contains inactive X chromosomal obligately methylated HpaII/MspI sites and single-base allelic polymorphisms in 5 to 10% of females. BAC cells, obtained by enzymatic dissociation of different fresh/paraffin-embedded tumoral foci from polymorphic individuals with multilobar or bilateral BAC, were sorted to homogeneity with a fluorescein-conjugated anticarcinoembryonic antigen and then subjected to genomic DNA extraction and HpaII digestion before polymerase chain reaction amplification and subsequent analysis of the product on denaturing gradient gel electrophoresis. The differing migrations of the single homoduplexes generated were indicative of BAC clonal nonidentity or multiclonality in three separate cases. The demonstration of multiclonality in some cases of BAC provides an alternate explanation for multifocality. PMID:7527541

  4. Geological and geophysical evidences for mud diapirism in south-eastern Sicily (Italy) and geodynamic implications

    NASA Astrophysics Data System (ADS)

    Barreca, Giovanni

    2014-12-01

    A recent investigation on the northern margin of the Hyblean Plateau in south-eastern Sicily highlights the occurrence of a clayey diapiric intrusion into the foreland carbonate series. The piercing body, exposed along a ∼270 long and ∼30 m deep NE-SW elongated quarry, consists of serpentinite-bearing clayey material. As suggested by the internal contractional features and by its geometric relations with the adjacent rocks, the clayey body intruded in the foreland series producing on its flanks a set of domino-arranged normal faults which nucleated as a result of gravitative collapse. Taking into account previous petrological studies, which provided information about the origin of the mud, a deep geodynamic model for the northern part of the Hyblean Plateau is here presented. The mud diapirs originated from the uprising of pre-existing serpentinite bodies and others products of alteration probably developed along an ancient ridge-transform intersection where a hydrothermally altered mantle wedge occurred. This interpretation is supported by seismic, magnetic and gravimetric anomalies beneath the analyzed area and has implications on its geodynamic evolution.

  5. Density-dependent habitat selection of spawning Chinook salmon: broad-scale evidence and implications.

    PubMed

    Falcy, Matthew R

    2015-03-01

    An extensive body of theory suggests that density-dependent habitat selection drives many fundamental ecological processes. The ideal free distribution and the ideal despotic distribution make contrasting predictions about the effect of total population size on relative abundances among habitats. Empirical assessment of these habitat selection models is uncommon because data must be collected over large temporal and spatial scales. I ask whether fluctuation in Chinook salmon (Oncorhynchus tshawytscha) spawner population size through time leads to different relative densities over space. Twenty-six years of monitoring data on spawning Chinook salmon across the entire coast of Oregon, USA, were used to evaluate models that make contrasting statements about the interactions of a latent population abundance parameter with physical habitat characteristics. There is strong information-theoretic support for models that include terms that allow the spatial variation in density to change as population size changes through time. Analysis of the best model reveals nonlinear isodars, which suggests a 'despotic' or 'preemptive' distribution of individuals across habitats, indicating that dominant or early-arriving individuals exclude others from breeding sites. This finding has implications for genetic dynamics, population dynamics and conservation metrics of these highly valued fish. The novel application of modelling techniques used here to assess mechanisms of habitat selection from observational data can be used in the emerging field of eco-evolutionary dynamics. PMID:25283166

  6. Identity as a Moderator and Mediator of Communication Effects: Evidence and Implications for Message Design.

    PubMed

    Comello, Maria Leonora G; Farman, Lisa

    2016-10-01

    Advertisements, movies, and other forms of media content have potential to change behaviors and antecedent psychological states by appealing to identity. However, the mechanisms that are responsible for persuasive effects of such content have not been adequately specified. A recently proposed model of communication effects (the prism model) advances the study of mechanisms and argues that identity can serve as both a moderator and mediator of communication effects on behavior-relevant outcomes. These intervening roles are made possible by the complex nature of identity (including multiple self-concepts and sensitivity to cues) and messages that cue the importance of and activate particular self-concepts. This article builds on development of the model by presenting empirical support based on re-analysis of an experiment in which participants viewed either a more-stigmatizing or less-stigmatizing portrayal of a recovering drug addict. In line with the model's propositions, exposure to the less-stigmatizing condition led to increases in perspective taking which then led to more acceptance (mediation by identity), while level of perspective taking also changed the effect of condition on acceptance (moderation by identity). These results provide support for the model's proposition of simultaneous intervening roles. The authors discuss implications for strategic communication research and practice. PMID:27351683

  7. Evidence that avian reovirus σNS is an RNA chaperone: implications for genome segment assortment.

    PubMed

    Borodavka, Alexander; Ault, James; Stockley, Peter G; Tuma, Roman

    2015-08-18

    Reoviruses are important human, animal and plant pathogens having 10-12 segments of double-stranded genomic RNA. The mechanisms controlling the assortment and packaging of genomic segments in these viruses, remain poorly understood. RNA-protein and RNA-RNA interactions between viral genomic segment precursors have been implicated in the process. While non-structural viral RNA-binding proteins, such as avian reovirus σNS, are essential for virus replication, the mechanism by which they assist packaging is unclear. Here we demonstrate that σNS assembles into stable elongated hexamers in vitro, which bind single-stranded nucleic acids with high affinity, but little sequence specificity. Using ensemble and single molecule fluorescence spectroscopy, we show that σNS also binds to a partially double-stranded RNA, resulting in gradual helix unwinding. The hexamer can bind multiple RNA molecules and exhibits strand-annealing activity, thus mediating conversion of metastable, intramolecular stem-loops into more stable heteroduplexes. We demonstrate that the ARV σNS acts as an RNA chaperone facilitating specific RNA-RNA interactions between genomic precursors during segment assortment and packaging.

  8. Gene–environment correlations: a review of the evidence and implications for prevention of mental illness

    PubMed Central

    Jaffee, SR; Price, TS

    2013-01-01

    Family studies have demonstrated genetic influences on environmental exposure: the phenomenon of gene–environment correlation (rGE). A few molecular genetic studies have confirmed the results, but the identification of rGE in studies that measure genes and environments faces several challenges. Using examples from studies in psychology and psychiatry, we integrate the behavioral and molecular genetic literatures on rGE, describe challenges in identifying rGE and discuss the implications of molecular genetic findings of rGE for future research on gene–environment interplay and for attempts to prevent disease by reducing environmental risk exposure. Genes affect environments indirectly, via behavior and personality characteristics. Associations between individual genetic variants and behaviors are typically small in magnitude, and downstream effects on environmental risk are further attenuated by behavioral mediation. Genotype–environment associations are most likely to be detected when the environment is behaviorally modifiable and highly specified and a plausible mechanism links gene and behavior. rGEs play an important causal role in psychiatric illness. Although research efforts should concentrate on elucidating the genetic underpinnings of behavior rather than the environment itself, the identification of rGE may suggest targets for environmental intervention even in highly heritable disease. Prevention efforts must address the possibility of confounding between rGE and gene–environment interaction (G × E). PMID:17453060

  9. Evidence that avian reovirus σNS is an RNA chaperone: implications for genome segment assortment

    PubMed Central

    Borodavka, Alexander; Ault, James; Stockley, Peter G.; Tuma, Roman

    2015-01-01

    Reoviruses are important human, animal and plant pathogens having 10–12 segments of double-stranded genomic RNA. The mechanisms controlling the assortment and packaging of genomic segments in these viruses, remain poorly understood. RNA–protein and RNA–RNA interactions between viral genomic segment precursors have been implicated in the process. While non-structural viral RNA-binding proteins, such as avian reovirus σNS, are essential for virus replication, the mechanism by which they assist packaging is unclear. Here we demonstrate that σNS assembles into stable elongated hexamers in vitro, which bind single-stranded nucleic acids with high affinity, but little sequence specificity. Using ensemble and single molecule fluorescence spectroscopy, we show that σNS also binds to a partially double-stranded RNA, resulting in gradual helix unwinding. The hexamer can bind multiple RNA molecules and exhibits strand-annealing activity, thus mediating conversion of metastable, intramolecular stem-loops into more stable heteroduplexes. We demonstrate that the ARV σNS acts as an RNA chaperone facilitating specific RNA–RNA interactions between genomic precursors during segment assortment and packaging. PMID:26109354

  10. Identity as a Moderator and Mediator of Communication Effects: Evidence and Implications for Message Design.

    PubMed

    Comello, Maria Leonora G; Farman, Lisa

    2016-10-01

    Advertisements, movies, and other forms of media content have potential to change behaviors and antecedent psychological states by appealing to identity. However, the mechanisms that are responsible for persuasive effects of such content have not been adequately specified. A recently proposed model of communication effects (the prism model) advances the study of mechanisms and argues that identity can serve as both a moderator and mediator of communication effects on behavior-relevant outcomes. These intervening roles are made possible by the complex nature of identity (including multiple self-concepts and sensitivity to cues) and messages that cue the importance of and activate particular self-concepts. This article builds on development of the model by presenting empirical support based on re-analysis of an experiment in which participants viewed either a more-stigmatizing or less-stigmatizing portrayal of a recovering drug addict. In line with the model's propositions, exposure to the less-stigmatizing condition led to increases in perspective taking which then led to more acceptance (mediation by identity), while level of perspective taking also changed the effect of condition on acceptance (moderation by identity). These results provide support for the model's proposition of simultaneous intervening roles. The authors discuss implications for strategic communication research and practice.

  11. GPS Evidence for Northward Motion of the Sinai Block: Implications for E. Mediterranean Tectonics

    NASA Astrophysics Data System (ADS)

    Mahmoud, S.; Reilinger, R. E.; McClusky, S.; Vernant, P.; Tealeb, A.

    2004-12-01

    We present GPS yearly survey-mode observations for the period 1997 to 2003 at 12 sites within and adjacent to the Sinai Peninsula to constrain motion of the Sinai Block. Sites in the Sinai Peninsula show northerly motion relative to Africa (Nubian plate) at an average rate of 1.5 +/- 1 mm/yr north and -0.8 +/- 1 mm/yr west (1 sigma). While there is some variability, 11 of 12 sites show northerly motion strongly suggesting that the Sinai as a whole is moving northward relative to Nubia. Continuous IGS GPS sites in Israel, west of the Dead Sea fault (greater than 45 km from the fault trace and outside the main zone of elastic strain accumulation) show a similar northerly sense of motion relative to Africa (~ 2.7 +/- 1mm/yr north and -0.9 +/- 1 mm/yr west), suggesting that the entire Sinai Block south of Lebanon is characterized by northward translation relative to Africa. Using an elastic block model we estimate slip rates for the Gulf of Aqaba - southern Dead Sea fault system of 5.1 +/- 0.7 mm/yr, left lateral, and along the Gulf of Suez of 3.0 +/- 0.5 mm/yr left lateral. Present-day opening of the Gulf of Suez is less than 1 mm/yr. This block model provides a quantitative, kinematic explanation for the first order, present-day tectonic character of the easternmost Mediterranean, including the Dead Sea fault system, the Gulf of Suez, and the Cyprus Arc.

  12. ACCUMULATION OF POLY-B-HYDROXYBUTYRATE IN A METHANE- ENRICHED, HALOGENATED, HYDROCARBON-DEGRADING SOIL COLUMN: IMPLICATIONS FOR MICROBIAL COMMUNITY STRUCTURE AND NUTRITIONAL STATUS

    EPA Science Inventory

    The prokarotic, endogenous storage polymer poly--hydroxybutyrate (PHB) accumulated in soil from a methane-enriched, halogenated hydrocarbon-degrading soil column. Based on phospholipid ester-linked fatty acid (PLFA) profiles, this mocrocosm has been previously reported to be sign...

  13. Cadmium, copper, and lead accumulation and bioconcentration in the vegetative and reproductive organs of Raphanus sativus: implications for plant performance and pollination.

    PubMed

    Hladun, Kristen R; Parker, David R; Trumble, John T

    2015-04-01

    Several studies have found high levels of cadmium (Cd), copper (Cu), and lead (Pb) in honey bee hives located near urbanized or industrial areas. Insect herbivores and pollinators may come in contact with environmental contaminants in the leaves and flowers they forage upon in these areas. Our study quantified which of these metals are accumulated in the tissues of a common weedy plant that can serve as a route of exposure for insects. We grew Raphanus sativus (crop radish) in semi-hydroponic sand culture in the greenhouse. Plants were irrigated with nutrient solutions containing Cd, Cu, or Pb at four concentrations (control, low, medium, high). Plant performance, floral traits, and metal accumulation were measured in various vegetative and reproductive plant organs. Floral traits and flower number were unaffected by all metal treatments. Copper accumulated at the highest concentrations in flowers compared to the other two metals. Copper and Cd had the highest translocation indices, as well as higher bioconcentration factors compared to Pb, which was mostly immobile in the plant. Copper posed the highest risk due to its high mobility within the plant. In particular, accumulation of metals in leaves and flowers suggests that herbivores and pollinators visiting and foraging on these tissues may be exposed to these potentially toxic compounds.

  14. Cadmium, copper, and lead accumulation and bioconcentration in the vegetative and reproductive organs of Raphanus sativus: implications for plant performance and pollination.

    PubMed

    Hladun, Kristen R; Parker, David R; Trumble, John T

    2015-04-01

    Several studies have found high levels of cadmium (Cd), copper (Cu), and lead (Pb) in honey bee hives located near urbanized or industrial areas. Insect herbivores and pollinators may come in contact with environmental contaminants in the leaves and flowers they forage upon in these areas. Our study quantified which of these metals are accumulated in the tissues of a common weedy plant that can serve as a route of exposure for insects. We grew Raphanus sativus (crop radish) in semi-hydroponic sand culture in the greenhouse. Plants were irrigated with nutrient solutions containing Cd, Cu, or Pb at four concentrations (control, low, medium, high). Plant performance, floral traits, and metal accumulation were measured in various vegetative and reproductive plant organs. Floral traits and flower number were unaffected by all metal treatments. Copper accumulated at the highest concentrations in flowers compared to the other two metals. Copper and Cd had the highest translocation indices, as well as higher bioconcentration factors compared to Pb, which was mostly immobile in the plant. Copper posed the highest risk due to its high mobility within the plant. In particular, accumulation of metals in leaves and flowers suggests that herbivores and pollinators visiting and foraging on these tissues may be exposed to these potentially toxic compounds. PMID:25845355

  15. Accumulate Repeat Accumulate Coded Modulation

    NASA Technical Reports Server (NTRS)

    Abbasfar, Aliazam; Divsalar, Dariush; Yao, Kung

    2004-01-01

    In this paper we propose an innovative coded modulation scheme called 'Accumulate Repeat Accumulate Coded Modulation' (ARA coded modulation). This class of codes can be viewed as serial turbo-like codes, or as a subclass of Low Density Parity Check (LDPC) codes that are combined with high level modulation. Thus at the decoder belief propagation can be used for iterative decoding of ARA coded modulation on a graph, provided a demapper transforms the received in-phase and quadrature samples to reliability of the bits.

  16. Airborne laser scan measurements of winter snow accumulation in high alpine catchments - hydrological implications and verification by ground penetrating radar at glacier surface

    NASA Astrophysics Data System (ADS)

    Helfricht, K.; Keuschnig, M.; Heilig, A.; Mayer, C.; Kuhn, M.

    2012-04-01

    The snow cover as storage of winter precipitation is a substantial source for runoff generation in high mountain catchments. Redistribution of solid precipitation, caused by wind and gravity, leads to a characteristic spatial distribution of snow accumulation which differs from simple model assumption of a homogenous snowpack increasing with altitude. Both, the distinct distribution of snow accumulation and the total amount of SWE stored in the snow cover, affect the magnitude and seasonality of melt water runoff. Complex relations exist between the spatial pattern of snow accumulation and the presence of glaciers and vice versa. For proper hydrological modeling in high mountain catchments, knowledge about snow cover distribution is an important requirement. To date, to evaluate modeling results, spatially insufficient point data on snow depths and SWE are usually available. On catchment scale, optical space-borne remote sensing techniques deliver areal extent of snow cover, but no snow depths and hence no volume of snow cover. Multi-temporal airborne laser scanning (ALS) is an active remote sensing method to obtain elevation changes extensively even in inaccessible alpine terrain. Before the start and at the end of accumulation season of winter 2010/2011, two airborne laser scan acquisitions were performed in the Ötztal Alps (Tirol, Austria). Differences of the respective digital elevation models were interpreted as snow depths and converted into SWE using a simple regression method between snow depths and snow density. Preferred snow accumulation areas were determined, e.g. wind sheltered depressions, the base of steep mountain walls and flat glacier surfaces. At catchment scale, solid precipitation is obviously redistributed from wind exposed mountain ridges to lower elevations, inducing characteristic elevations of maximum snow accumulation. Overall, catchment precipitation derived from snow accumulation is a valuable reference for precipitation approaches in

  17. Empirical Evidence for Self-Organized Patterns in California Wildfire Sizes: Implications for Landscape Resilience

    NASA Astrophysics Data System (ADS)

    Povak, N. A.; Hessburg, P. F.

    2009-05-01

    Wildfires are an important disturbance in many western US ecosystems and are integral in shaping spatial and temporal vegetation patterns. Ecological resilience has been described as the amount of disturbance that an ecosystem could withstand without changing self-organized processes and structures. Inherent in resilient systems are observable self-organized patterns in vegetation and processes on the landscape. It is theorized that self-organized systems are capable of withstanding a large range of disturbance sizes and intensities without significantly changing the resultant distribution of vegetation patch sizes over time. Past research has used power-law statistics to describe self-organization in wildfire behavior, and we extend this research using several different methods to identify evidence for landscape resilience over a large geographic area. We used a catalogue of California wildfires (>1ha; 1950-2007) grouped at multiple levels within Bailey's hierarchy of ecoregions to (1) identify self-organized patterns in wildfire size distributions across the state, (2) identify lower and upper limits on self-organized behavior, and (3) find links between these patterns and top-down and bottom-up processes. Within most ecoregions we found reliable evidence for self-organized behavior in wildfire size distributions. Evidence included good fits of: (1) 2-3 parameter statistical distributions within the Pareto and Generalized Beta II (P/GB2) family of distributions over the entire range of fire event sizes; these distributions all have in common a power-law tail, (2) the Pareto I (power-law) distribution to the right-tail of the fire-size distributions, and (3) broken-stick regression models to the inverse cumulative distribution functions for fire sizes. For most ecoregions, self-organized properties were generally limited to fires within 100 to 10000 ha, indicating that meso-scale processes controlling fire sizes likely are acting at this scale. Scaling parameters

  18. Local root abscisic acid (ABA) accumulation depends on the spatial distribution of soil moisture in potato: implications for ABA signalling under heterogeneous soil drying.

    PubMed

    Puértolas, Jaime; Conesa, María R; Ballester, Carlos; Dodd, Ian C

    2015-04-01

    Patterns of root abscisic acid (ABA) accumulation ([ABA]root), root water potential (Ψroot), and root water uptake (RWU), and their impact on xylem sap ABA concentration ([X-ABA]) were measured under vertical partial root-zone drying (VPRD, upper compartment dry, lower compartment wet) and horizontal partial root-zone drying (HPRD, two lateral compartments: one dry, the other wet) of potato (Solanum tuberosum L.). When water was withheld from the dry compartment for 0-10 d, RWU and Ψroot were similarly lower in the dry compartment when soil volumetric water content dropped below 0.22cm(3) cm(-3) for both spatial distributions of soil moisture. However, [ABA]root increased in response to decreasing Ψroot in the dry compartment only for HPRD, resulting in much higher ABA accumulation than in VPRD. The position of the sampled roots (~4cm closer to the surface in the dry compartment of VPRD than in HPRD) might account for this difference, since older (upper) roots may accumulate less ABA in response to decreased Ψroot than younger (deeper) roots. This would explain differences in root ABA accumulation patterns under vertical and horizontal soil moisture gradients reported in the literature. In our experiment, these differences in root ABA accumulation did not influence [X-ABA], since the RWU fraction (and thus ABA export to shoots) from the dry compartment dramatically decreased simultaneously with any increase in [ABA]root. Thus, HPRD might better trigger a long-distance ABA signal than VPRD under conditions allowing simultaneous high [ABA]root and relatively high RWU fraction. PMID:25547916

  19. Smooth Muscle Cell Foam Cell Formation, Apolipoproteins, and ABCA1 in Intracranial Aneurysms: Implications for Lipid Accumulation as a Promoter of Aneurysm Wall Rupture.

    PubMed

    Ollikainen, Eliisa; Tulamo, Riikka; Lehti, Satu; Lee-Rueckert, Miriam; Hernesniemi, Juha; Niemelä, Mika; Ylä-Herttuala, Seppo; Kovanen, Petri T; Frösen, Juhana

    2016-07-01

    Saccular intracranial aneurysm (sIA) aneurysm causes intracranial hemorrhages that are associated with high mortality. Lipid accumulation and chronic inflammation occur in the sIA wall. A major mechanism for lipid clearance from arteries is adenosine triphosphate-binding cassette A1 (ABCA1)-mediated lipid efflux from foam cells to apolipoprotein A-I (apoA-I). We investigated the association of wall degeneration, inflammation, and lipid-related parameters in tissue samples of 16 unruptured and 20 ruptured sIAs using histology and immunohistochemistry. Intracellular lipid accumulation was associated with wall remodeling (p = 0.005) and rupture (p = 0.020). Foam cell formation was observed in smooth muscle cells, in addition to CD68- and CD163-positive macrophages. Macrophage infiltration correlated with intracellular lipid accumulation and apolipoproteins, including apoA-I. ApoA-I correlated with markers of lipid accumulation and wall degeneration (p = 0.01). ApoA-I-positive staining colocalized with ABCA1-positive cells particularly in sIAs with high number of smooth muscle cells (p = 0.003); absence of such colocalization was associated with wall degeneration (p = 0.017). Known clinical risk factors for sIA rupture correlated inversely with apoA-I. We conclude that lipid accumulation associates with sIA wall degeneration and risk of rupture, possibly via formation of foam cells and subsequent loss of mural cells. Reduced removal of lipids from the sIA wall via ABCA1-apoA-I pathway may contribute to this process.

  20. Local root abscisic acid (ABA) accumulation depends on the spatial distribution of soil moisture in potato: implications for ABA signalling under heterogeneous soil drying

    PubMed Central

    Puértolas, Jaime; Conesa, María R.; Ballester, Carlos; Dodd, Ian C.

    2015-01-01

    Patterns of root abscisic acid (ABA) accumulation ([ABA]root), root water potential (Ψroot), and root water uptake (RWU), and their impact on xylem sap ABA concentration ([X-ABA]) were measured under vertical partial root-zone drying (VPRD, upper compartment dry, lower compartment wet) and horizontal partial root-zone drying (HPRD, two lateral compartments: one dry, the other wet) of potato (Solanum tuberosum L.). When water was withheld from the dry compartment for 0–10 d, RWU and Ψroot were similarly lower in the dry compartment when soil volumetric water content dropped below 0.22cm3 cm–3 for both spatial distributions of soil moisture. However, [ABA]root increased in response to decreasing Ψroot in the dry compartment only for HPRD, resulting in much higher ABA accumulation than in VPRD. The position of the sampled roots (~4cm closer to the surface in the dry compartment of VPRD than in HPRD) might account for this difference, since older (upper) roots may accumulate less ABA in response to decreased Ψroot than younger (deeper) roots. This would explain differences in root ABA accumulation patterns under vertical and horizontal soil moisture gradients reported in the literature. In our experiment, these differences in root ABA accumulation did not influence [X-ABA], since the RWU fraction (and thus ABA export to shoots) from the dry compartment dramatically decreased simultaneously with any increase in [ABA]root. Thus, HPRD might better trigger a long-distance ABA signal than VPRD under conditions allowing simultaneous high [ABA]root and relatively high RWU fraction. PMID:25547916

  1. Local root abscisic acid (ABA) accumulation depends on the spatial distribution of soil moisture in potato: implications for ABA signalling under heterogeneous soil drying.

    PubMed

    Puértolas, Jaime; Conesa, María R; Ballester, Carlos; Dodd, Ian C

    2015-04-01

    Patterns of root abscisic acid (ABA) accumulation ([ABA]root), root water potential (Ψroot), and root water uptake (RWU), and their impact on xylem sap ABA concentration ([X-ABA]) were measured under vertical partial root-zone drying (VPRD, upper compartment dry, lower compartment wet) and horizontal partial root-zone drying (HPRD, two lateral compartments: one dry, the other wet) of potato (Solanum tuberosum L.). When water was withheld from the dry compartment for 0-10 d, RWU and Ψroot were similarly lower in the dry compartment when soil volumetric water content dropped below 0.22cm(3) cm(-3) for both spatial distributions of soil moisture. However, [ABA]root increased in response to decreasing Ψroot in the dry compartment only for HPRD, resulting in much higher ABA accumulation than in VPRD. The position of the sampled roots (~4cm closer to the surface in the dry compartment of VPRD than in HPRD) might account for this difference, since older (upper) roots may accumulate less ABA in response to decreased Ψroot than younger (deeper) roots. This would explain differences in root ABA accumulation patterns under vertical and horizontal soil moisture gradients reported in the literature. In our experiment, these differences in root ABA accumulation did not influence [X-ABA], since the RWU fraction (and thus ABA export to shoots) from the dry compartment dramatically decreased simultaneously with any increase in [ABA]root. Thus, HPRD might better trigger a long-distance ABA signal than VPRD under conditions allowing simultaneous high [ABA]root and relatively high RWU fraction.

  2. Smooth Muscle Cell Foam Cell Formation, Apolipoproteins, and ABCA1 in Intracranial Aneurysms: Implications for Lipid Accumulation as a Promoter of Aneurysm Wall Rupture.

    PubMed

    Ollikainen, Eliisa; Tulamo, Riikka; Lehti, Satu; Lee-Rueckert, Miriam; Hernesniemi, Juha; Niemelä, Mika; Ylä-Herttuala, Seppo; Kovanen, Petri T; Frösen, Juhana

    2016-07-01

    Saccular intracranial aneurysm (sIA) aneurysm causes intracranial hemorrhages that are associated with high mortality. Lipid accumulation and chronic inflammation occur in the sIA wall. A major mechanism for lipid clearance from arteries is adenosine triphosphate-binding cassette A1 (ABCA1)-mediated lipid efflux from foam cells to apolipoprotein A-I (apoA-I). We investigated the association of wall degeneration, inflammation, and lipid-related parameters in tissue samples of 16 unruptured and 20 ruptured sIAs using histology and immunohistochemistry. Intracellular lipid accumulation was associated with wall remodeling (p = 0.005) and rupture (p = 0.020). Foam cell formation was observed in smooth muscle cells, in addition to CD68- and CD163-positive macrophages. Macrophage infiltration correlated with intracellular lipid accumulation and apolipoproteins, including apoA-I. ApoA-I correlated with markers of lipid accumulation and wall degeneration (p = 0.01). ApoA-I-positive staining colocalized with ABCA1-positive cells particularly in sIAs with high number of smooth muscle cells (p = 0.003); absence of such colocalization was associated with wall degeneration (p = 0.017). Known clinical risk factors for sIA rupture correlated inversely with apoA-I. We conclude that lipid accumulation associates with sIA wall degeneration and risk of rupture, possibly via formation of foam cells and subsequent loss of mural cells. Reduced removal of lipids from the sIA wall via ABCA1-apoA-I pathway may contribute to this process. PMID:27283327

  3. Persistence of Ebola virus in various body fluids during convalescence: evidence and implications for disease transmission and control.

    PubMed

    Chughtai, A A; Barnes, M; Macintyre, C R

    2016-06-01

    The aim of this study was to review the current evidence regarding the persistence of Ebola virus (EBOV) in various body fluids during convalescence and discuss its implication on disease transmission and control. We conducted a systematic review and searched articles from Medline and EMBASE using key words. We included studies that examined the persistence of EBOV in various body fluids during the convalescent phase. Twelve studies examined the persistence of EBOV in body fluids, with around 800 specimens tested in total. Available evidence suggests that EBOV can persist in some body fluids after clinical recovery and clearance of virus from the blood. EBOV has been isolated from semen, aqueous humor, urine and breast milk 82, 63, 26 and 15 days after onset of illness, respectively. Viral RNA has been detectable in semen (day 272), aqueous humor (day 63), sweat (day 40), urine (day 30), vaginal secretions (day 33), conjunctival fluid (day 22), faeces (day 19) and breast milk (day 17). Given high case fatality and uncertainties around the transmission characteristics, patients should be considered potentially infectious for a period of time after immediate clinical recovery. Patients and their immediate contacts should be informed about these risks. Convalescent patients may need to abstain from sex for at least 9 months or should use condoms until their semen tests are negative. Breastfeeding should be avoided during the convalescent phase. There is a need for more research on persistence, and a uniform approach to infection control guidelines in convalescence. PMID:26808232

  4. Persistence of Ebola virus in various body fluids during convalescence: evidence and implications for disease transmission and control.

    PubMed

    Chughtai, A A; Barnes, M; Macintyre, C R

    2016-06-01

    The aim of this study was to review the current evidence regarding the persistence of Ebola virus (EBOV) in various body fluids during convalescence and discuss its implication on disease transmission and control. We conducted a systematic review and searched articles from Medline and EMBASE using key words. We included studies that examined the persistence of EBOV in various body fluids during the convalescent phase. Twelve studies examined the persistence of EBOV in body fluids, with around 800 specimens tested in total. Available evidence suggests that EBOV can persist in some body fluids after clinical recovery and clearance of virus from the blood. EBOV has been isolated from semen, aqueous humor, urine and breast milk 82, 63, 26 and 15 days after onset of illness, respectively. Viral RNA has been detectable in semen (day 272), aqueous humor (day 63), sweat (day 40), urine (day 30), vaginal secretions (day 33), conjunctival fluid (day 22), faeces (day 19) and breast milk (day 17). Given high case fatality and uncertainties around the transmission characteristics, patients should be considered potentially infectious for a period of time after immediate clinical recovery. Patients and their immediate contacts should be informed about these risks. Convalescent patients may need to abstain from sex for at least 9 months or should use condoms until their semen tests are negative. Breastfeeding should be avoided during the convalescent phase. There is a need for more research on persistence, and a uniform approach to infection control guidelines in convalescence.

  5. Acceleration of large active earthflows triggered by massive snow accumulation events: evidences from monitoring the Corvara landslide in early 2014 (Dolomites, Italy)

    NASA Astrophysics Data System (ADS)

    Corsini, Alessandro; Mulas, Marco; Marcato, Gianluca; Chinellato, Giulia; Mair, Volkmar

    2015-04-01

    In the Dolomites of Italy, snowfall during winter 2013/2014 was exceptionally abundant. Major snowfall events occurred from late December 2013 to mid-March 2014. Snow accumulation in Badia Valley peaked in early February: from 2 to 4 meters with a positive gradient respect to altimetry and accordingly to wind accumulation zones. Below 2000 m asl, due to the mild temperatures recorded before the onset of snowfall, the relatively dry snow cover was mostly deposited on top of unfrozen soils. The Corvara landslide is a large active earthflow located close to Corvara in Badia, at an elevation from 2000 to 1600 m. It's displacement rate before, during and after the exceptional snowfall period was monitored at high temporal frequency. Surface displacement was measured bi-weekly by differential GPS in several benchmarks in the source, track and accumulation zone. Deep displacement was monitored semi-continuously by two in-place inclinometers at 48 m depth in the accumulation zone, across the main deep-seated sliding surface. Results show an acceleration of movements, both at surface and at depth, soon after the massive snow accumulation event of 31st January to 2nd February 2014, which suddenly increased snow thickness from 1 to more than 2 metres. Short time lags between the onset of the acceleration of movements in the source, the track and the accumulation zones were also recorded. The landslide then maintained a relatively constant velocity during the high snow cover period extended to earlyApril and underwent a progressive deceleration during the snowmelt period that lasted until mid-June. The fact that the acceleration of the Corvara earthflow was triggered by a massive and rapid snow accumulation event, provides a quite different perspective from the generally adopted one that considers the destabilizing effect of snow only in relation to the increase of groundwater level during rapid snowmelt. A full explanation of the processes associated to the dynamics observed

  6. Mind-body therapies: evidence and implications in advanced oncology practice.

    PubMed

    Mayden, Kelley D

    2012-11-01

    The idea that thoughts and emotions influence health outcomes is an ancient concept that was initially abandoned by Western medicine researchers. Today, researchers are showing a renewed interest in the interactions of the mind and body and the role these interactions play in disease formation and recovery. Complementary and alternative interventions, such as mind-body therapies, are increasingly being used by cancer survivors for disease prevention, immune system enhancement, and symptom control. Traditional training has not been structured to provide advanced practitioners with an in-depth knowledge of the clinical applications of mind-body therapies. The aim of this article is to acquaint the reader with common mind-body modalities (meditation/mindfulness-based stress reduction, relaxation therapy, cognitive-behavioral therapy, hypnosis, biofeedback, music therapy, art therapy, support groups, and aromatherapy) and to examine important evidence in support of or against their clinical application.

  7. The health implications of financial crisis: A review of the evidence

    PubMed Central

    Stuckler, David; Basu, Sanjay; Suhrcke, Marc; McKee, Martin

    2009-01-01

    What will the current economic crisis mean for the health of the people of Northern Ireland? We review the experience of three major economic crises in the 20th century: the Great Depression (1929), the Post-communist Depression (early 1990s) and the East Asian financial crisis (late 1990s). Available evidence suggests that health is at risk in times of rapid economic change, in both booms and busts. However the impact on mortality is exacerbated where people have easy access to the means to harm themselves and is ameliorated by the presence of strong social cohesion and social protection systems. On this basis, Northern Ireland may escape relatively unscathed in the short term but as every crisis also provides an opportunity, this is an appropriate time for the Northern Ireland Executive to reflect on whether they are making a sufficient investment in the long term health of their population. PMID:19907678

  8. D0 Evidence for CP Violation and Implication for CPT Violation in B-Meson Mixing

    SciTech Connect

    Kooten, R.Van; /Indiana U.

    2010-08-01

    A D0 analysis measuring the charge asymmetry A{sub sl}{sup b} of like-sign dimuon events due to semileptonic b-hadron decays at the Fermilab Tevatron Collider is described. It differs by 3.2 standard deviations from the Standard Model prediction to provide first evidence of CPT-invariant anomalous CP violation in the mixing of neutral B mesons, and is compared to the CP-violating phase obtained from a D0 analysis of the time-dependent decay angles in B{sub s}{sup 0} {yields} J/{psi}{phi}. If CPT violation is allowed, the dimuon asymmetry also yields the first sensitivity to CPT violation in the B{sub s}{sup 0} system.

  9. Caffeine Use Disorder: A Review of the Evidence and Future Implications.

    PubMed

    Addicott, Merideth A

    2014-09-01

    The latest edition of the Diagnostic and Statistical Manual (DSM-5) has introduced new provisions for caffeine-related disorders. Caffeine Withdrawal is now an officially recognized diagnosis, and criteria for caffeine use disorder have been proposed for additional study. caffeine use disorder is intended to be characterized by cognitive, behavioral, and physiological symptoms indicative of caffeine use despite significant caffeine-related problems, similar to other Substance Use Disorders. However, since nonproblematic caffeine use is so common and widespread, it may be difficult for some health professionals to accept that caffeine use can result in the same types of pathological behaviors caused by alcohol, cocaine, opiates, or other drugs of abuse. Yet there is evidence that some individuals are psychologically and physiologically dependent on caffeine, although the prevalence and severity of these problems is unknown. This article reviews the recent changes to the DSM, the concerns regarding these changes, and some potential impacts these changes could have on caffeine consumers. PMID:25089257

  10. Bilingual Children with Primary Language Impairment: Issues, Evidence and Implications for Clinical Actions

    PubMed Central

    Kohnert, Kathryn

    2010-01-01

    A clear understanding of how to best provide clinical serves to bilingual children with suspected or confirmed primary language impairment (PLI) is predicated on understanding typical development in dual-language learners as well as the PLI profile. This article reviews general characteristics of children learning two languages, including three that challenge the diagnosis and treatment of PLI; uneven distribution of abilities in the child's two languages, cross-linguistic associations within bilingual learners, and individual variation in response to similar social circumstances. The diagnostic category of PLI (also referred to in the literature as specific language impairment or SLI) is described with attention to how language impairment, in the face of otherwise typical development, manifests in children learning two languages. Empirical evidence related to differential diagnosis of PLI in bilingual children is then reviewed and issues related to the generalization of treatment gains in dual-language learners with PLI are introduced. PMID:20371080

  11. Atypical femoral fractures and bisphosphonate use: current evidence and clinical implications

    PubMed Central

    Saita, Yoshitomo; Kaneko, Kazuo

    2015-01-01

    Osteoporosis is a disease characterized by a low bone volume and deterioration of the bone quality, which increases the risk of low-energy fractures. Bisphosphonate (BP) treatment increases the bone mass and reduces the risk of fractures in patients with osteoporosis by suppressing bone resorption. In spite of its clinical benefits, the long-term use of BPs has been linked to the occurrence of atypical femoral fractures (AFFs). Although the evidence had been controversial regarding the association between the occurrence of AFFs and BP use, more recent studies with radiographic adjudication have indicated the significant associations between them. However, the pathogenesis of AFFs is not completely understood. The most popular hypothesis has suggested that the suppression of bone turnover by BPs is responsible; however, some recent reports have implied the involvement of pathophysiological alterations of the bone quality and fracture repair process. In this review, we summarize and discuss the epidemiology, risk factors and pathology of AFFs. PMID:26137208

  12. Mind-Body Therapies: Evidence and Implications in Advanced Oncology Practice

    PubMed Central

    Mayden,, Kelley D.

    2012-01-01

    The idea that thoughts and emotions influence health outcomes is an ancient concept that was initially abandoned by Western medicine researchers. Today, researchers are showing a renewed interest in the interactions of the mind and body and the role these interactions play in disease formation and recovery. Complementary and alternative interventions, such as mind-body therapies, are increasingly being used by cancer survivors for disease prevention, immune system enhancement, and symptom control. Traditional training has not been structured to provide advanced practitioners with an in-depth knowledge of the clinical applications of mind-body therapies. The aim of this article is to acquaint the reader with common mind-body modalities (meditation/mindfulness-based stress reduction, relaxation therapy, cognitive-behavioral therapy, hypnosis, biofeedback, music therapy, art therapy, support groups, and aromatherapy) and to examine important evidence in support of or against their clinical application. PMID:25031967

  13. DNA evidence in rape cases and the Debbie Smith Act: forensic practice and criminal justice implications.

    PubMed

    Telsavaara, Terhi V T; Arrigo, Bruce A

    2006-10-01

    The Debbie Smith or "Justice for All" Act was passed on November 1, 2004. The act addresses the problem of collecting and analyzing DNA evidence from backlogged rape kits sitting in crime laboratories around the country. Presently, no empirical data exist by which to assess the soundness of the legislation. However, the act clearly affects discrete operations within the forensic and criminal justice systems. This article explores the relative merits of the Debbie Smith law, highlighting changes in Sexual Assault Nurse Examiner (SANE) programs, law enforcement, court administration, correctional treatment, and juvenile justice practices. Concerns linked to the likely impact of the "Justice for All" Act raise significant questions about its overall programmatic utility and treatment efficacy.

  14. Field-based evidence for devolatilization in subduction zones: implications for arc magmatism.

    PubMed

    Bebout, G E

    1991-01-25

    Metamorphic rocks on Santa Catalina Island, California, afford examination of fluid-related processes at depths of 15 to 45 kilometers in an Early Cretaceous subduction zone. A combination of field, stable isotope, and volatile content data for the Catalina Schist indicates kilometer-scale transport of large amounts of water-rich fluid with uniform oxygen and hydrogen isotope compositions. The fluids were liberated in devolatilizing, relatively low-temperature (400 degrees to 600 degrees C) parts of the subduction zone, primarily by chlorite-breakdown reactions. An evaluation of pertinent phase equilibria indicates that chlorite in mafic and sedimentary rocks and melange may stabilize a large volatile component to great depths (perhaps >100 kilometers), depending on the thermal structure of the subduction zone. This evidence for deep volatile subduction and large-scale flow of slab-derived, water-rich fluids lends credence to models that invoke fluid addition to sites of arc magma genesis.

  15. Evidence for Cambrian deformation in the Ellsworth-Whitmore Mountains terrane, Antarctica: Stratigraphic and tectonic implications

    NASA Astrophysics Data System (ADS)

    Duebendorfer, Ernest M.; Rees, Margaret N.

    1998-01-01

    The Ellsworth-Whitmore Mountains terrane is a large geologically and geophysically defined crustal block that lies between the Transantarctic Mountains and West Antarctica. The Cambrian position of the terrane is controversial, with many workers placing it between East Antarctica and southern Africa and distant from Cambrian orogenic belts. We present structural and stratigraphic evidence for Cambrian deformation in the Heritage Range, Ellsworth Mountains. From our revised stratigraphy and structural history of the Heritage Range, we propose that the Ellsworth-Whitmore Mountains block was located within the belt of Pan-African deformation, within the Late Cambrian continental arc, and was part of a collage of allochthonous terranes that included the Queen Maud terrane and probably the Bowers terrane of Antarctica. These terranes were situated outboard of Coats Land in the Cambrian and were subsequently translated and accreted to East Antarctica, probably during early Paleozoic time.

  16. Gas Evidence and Seepage: Implications and Subsidence in the Elkhorn Slough, CA

    NASA Astrophysics Data System (ADS)

    Garcia-Garcia, A.; King, N.; Sims, H.; Lopez, M.; Levey, M. D.; Shipton, G.; Watson, E. B.; Eby, R.

    2013-12-01

    The presence of gas pockets underneath the sediments of the Elkhorn Slough, a 10-km long, 1200-hectare tidal estuary located in Monterey Bay, has been imaged for the first time. Seismic surveys were run in 2011-2012 with an EdgeTech SB-424 full-spectrum sub-bottom CHIRP profiler, used with a default pulse which generates a sweep frequency of 4 kHz - 24 kHz for 10 ms, and a vertical resolution of 0.4 m. This system performed ideally in this shallow environment. Preliminary interpretation of the data shows multiple and widespread evidence of gas as acoustic blanking, acoustic turbidity, and acoustic plumes. The interpreted gas affects the sedimentary column from 5 m below the present channel all the way up to the surface. The gas front of these pockets is buried under the last two seismic units below the channel floor, and in some cases, reaches the surface of the sedimentary column. There are also indications of seepage from these pockets towards the water column, suggesting the seal is no longer effective. Multiples cores were taken between 2008 and 2011 and they confirm the presence of methane (as well as gas cracking evidence in XRays). The areas with unstable methane gas affect this delicate environment, which is currently under a watch for subsidence and strong erosion. The gas seepage can be triggering further collapse of sediments and enhancing the subsidence. In the present work we discuss these factors as well as aim to quantify how much gas the Slough sediments hold and how much is escaping at present. Acknowledgments: CSUMB (chirp), ESNEER staff for their support. The ';Dr. Douglas Garrison Fund' for Educational Excellence (MPC) and ONR supported this research. Figure 1. Chirp examples showing interpreted gas seepage (above) and gas pockets within the sediments (below).

  17. Dementia in western Europe: epidemiological evidence and implications for policy making.

    PubMed

    Wu, Yu-Tzu; Fratiglioni, Laura; Matthews, Fiona E; Lobo, Antonio; Breteler, Monique M B; Skoog, Ingmar; Brayne, Carol

    2016-01-01

    Dementia is receiving increasing attention from governments and politicians. Epidemiological research based on western European populations done 20 years ago provided key initial evidence for dementia policy making, but these estimates are now out of date because of changes in life expectancy, living conditions, and health profiles. To assess whether dementia occurrence has changed during the past 20-30 years, investigators of five different studies done in western Europe (Sweden [Stockholm and Gothenburg], the Netherlands [Rotterdam], the UK [England], and Spain [Zaragoza]) have compared dementia occurrence using consistent research methods between two timepoints in well-defined geographical areas. Findings from four of the five studies showed non-significant changes in overall dementia occurrence. The only significant reduction in overall prevalence was found in the study done in the UK, powered and designed explicitly from its outset to detect change across generations (decrease in prevalence of 22%; p=0.003). Findings from the study done in Zaragoza (Spain) showed a significant reduction in dementia prevalence in men (43%; p=0.0002). The studies estimating incidence done in Stockholm and Rotterdam reported non-significant reductions. Such reductions could be the outcomes from earlier population-level investments such as improved education and living conditions, and better prevention and treatment of vascular and chronic conditions. This evidence suggests that attention to optimum health early in life might benefit cognitive health late in life. Policy planning and future research should be balanced across primary (policies reducing risk and increasing cognitive reserve), secondary (early detection and screening), and tertiary (once dementia is present) prevention. Each has their place, but upstream primary prevention has the largest effect on reduction of later dementia occurrence and disability.

  18. PET evidence for a role for striatal dopamine in the attentional blink: functional implications.

    PubMed

    Slagter, Heleen A; Tomer, Rachel; Christian, Bradley T; Fox, Andrew S; Colzato, Lorenza S; King, Carlye R; Murali, Dhanabalan; Davidson, Richard J

    2012-09-01

    Our outside world changes continuously, for example, when driving through traffic. An important question is how our brain deals with this constant barrage of rapidly changing sensory input and flexibly selects only newly goal-relevant information for further capacity-limited processing in working memory. The challenge our brain faces is experimentally captured by the attentional blink (AB): an impairment in detecting the second of two target stimuli presented in close temporal proximity among distracters. Many theories have been proposed to explain this deficit in processing goal-relevant information, with some attributing the AB to capacity limitations related to encoding of the first target and others assigning a critical role to on-line selection mechanisms that control access to working memory. The current study examined the role of striatal dopamine in the AB, given its known role in regulating the contents of working memory. Specifically, participants performed an AB task and their basal level of dopamine D2-like receptor binding was measured using PET and [F-18]fallypride. As predicted, individual differences analyses showed that greater D2-like receptor binding in the striatum was associated with a larger AB, implicating striatal dopamine and mechanisms that control access to working memory in the AB. Specifically, we propose that striatal dopamine may determine the AB by regulating the threshold for working memory updating, providing a testable physiological basis for this deficit in gating rapidly changing visual information. A challenge for current models of the AB lies in connecting more directly to these neurobiological data. PMID:22663253

  19. Experimental evidence for friction-enhancing integumentary modifications of chameleons and associated functional and evolutionary implications.

    PubMed

    Khannoon, Eraqi R; Endlein, Thomas; Russell, Anthony P; Autumn, Kellar

    2014-01-22

    The striking morphological convergence of hair-like integumentary derivatives of lizards and arthropods (spiders and insects) demonstrates the importance of such features for enhancing purchase on the locomotor substrate. These pilose structures are responsible for the unique tractive abilities of these groups of animals, enabling them to move with seeming ease on overhanging and inverted surfaces, and to traverse inclined smooth substrates. Three groups of lizards are well known for bearing adhesion-promoting setae on their digits: geckos, anoles and skinks. Similar features are also found on the ventral subdigital and distal caudal skin of chameleons. These have only recently been described in any detail, and structurally and functionally are much less well understood than are the setae of geckos and anoles. The seta-like structures of chameleons are not branched (a characteristic of many geckos), nor do they terminate in spatulate tips (which is characteristic of geckos, anoles and skinks). They are densely packed and have attenuated blunt, globose tips or broad, blade-like shafts that are flattened for much of their length. Using a force transducer, we tested the hypothesis that these structures enhance friction and demonstrate that the pilose skin has a greater frictional coefficient than does the smooth skin of these animals. Our results are consistent with friction being generated as a result of side contact of the integumentary filaments. We discuss the evolutionary and functional implications of these seta-like structures in comparison with those typical of other lizard groups and with the properties of seta-mimicking synthetic structures.

  20. Do Child Development Accounts Promote Account Holding, Saving, and Asset Accumulation for Children's Future? Evidence from a Statewide Randomized Experiment

    ERIC Educational Resources Information Center

    Nam, Yunju; Kim, Youngmi; Clancy, Margaret; Zager, Robert; Sherraden, Michael

    2013-01-01

    This study examines the impacts of Child Development Accounts (CDAs) on account holding, saving, and asset accumulation for children, using data from the SEED for Oklahoma Kids experiment (SEED OK). SEED OK, a policy test of universal and progressive CDAs, provides a 529 college savings plan account to every infant in the treatment group with…

  1. Evidence for cross-reactivity of JAM-C antibodies: implications for cellular localization studies

    PubMed Central

    Betanzos, Abigail; Schnoor, Michael; Severson, Eric A.; Liang, Tony W.; Parkos, Charles A.

    2010-01-01

    Background information JAM-C (junctional adhesion molecule C) has been implicated in the regulation of leukocyte migration, cell polarity, spermatogenesis, angiogenesis and nerve conduction. JAM-C has been also reported to concentrate at TJs (tight junctions) and desmosomes, although detailed localization studies remain incomplete. Results Monoclonal (LUCA14, MAB1189, Gi11, and PACA4) and polyclonal (40–9000) antibodies were employed to evaluate JAM-C expression/localization in various epithelial cell lines. However, RT–PCR (reverse transcription– PCR) assays revealed no JAM-C mRNA in SK-CO15, HeLa and HPAF-II cells, whereas abundant mRNA was detected in platelets, Caco-2 and ARPE cells. Interestingly, immunofluorescence localization in all cells revealed strong intercellular junctional staining with all of the above antibodies, except PACA4. Given the positive staining results in cells lacking JAM-C mRNA, immunoblot analyses were performed. Western blots revealed a prominent protein band at 52 kDa in all cells tested with all antibodies except PACA4. However, the correct size of JAM-C (37 kDa) was only detected in cells containing JAM-C mRNA. Immunofluorescence staining of JAM-C mRNA-expressing Caco-2 cells using mAb PACA4 revealed co-localization with occludin and ZO-1 (zonula occludens 1) at TJs. Analyses by MS identified the cross-reactive 52 kDa protein band as K8 (keratin 8). Furthermore, siRNA (small interfering RNA)-mediated downregulation of K8 in JAM-C mRNA-negative cells resulted in diminished junctional staining along with a reduction in the intensity of the 52 kDa protein band. Using an antibody specific for K8 phosphorylated at Ser73, the 52 kDa protein was identified as this phosphorylated form of K8. Conclusions The results from the present study demonstrate that a majority of available anti-human JAM-C antibodies cross-react with phosphorylated K8 and suggest that cellular localization studies using these reagents should be interpreted with

  2. Evidence and implications of recent and projected climate change in Alaska's forest ecosystems

    USGS Publications Warehouse

    Wolken, Jane M.; Hollingsworth, Teresa N.; Rupp, T. Scott; Chapin, Stuart III; Trainor, Sarah F.; Barrett, Tara M.; Sullivan, Patrick F.; McGuire, A. David; Euskirchen, Eugénie S.; Hennon, Paul E.; Beever, Erik A.; Conn, Jeff S.; Crone, Lisa K.; D'Amore, David V.; Fresco, Nancy; Hanley, Thomas A.; Kielland, Knut; Kruse, James J.; Patterson, Trista; Schuur, Edward A.G.; Verbyla, David L.; Yarie, John

    2011-01-01

    The structure and function of Alaska's forests have changed significantly in response to a changing climate, including alterations in species composition and climate feedbacks (e.g., carbon, radiation budgets) that have important regional societal consequences and human feedbacks to forest ecosystems. In this paper we present the first comprehensive synthesis of climate-change impacts on all forested ecosystems of Alaska, highlighting changes in the most critical biophysical factors of each region. We developed a conceptual framework describing climate drivers, biophysical factors and types of change to illustrate how the biophysical and social subsystems of Alaskan forests interact and respond directly and indirectly to a changing climate. We then identify the regional and global implications to the climate system and associated socio-economic impacts, as presented in the current literature. Projections of temperature and precipitation suggest wildfire will continue to be the dominant biophysical factor in the Interior-boreal forest, leading to shifts from conifer- to deciduous-dominated forests. Based on existing research, projected increases in temperature in the Southcentral- and Kenai-boreal forests will likely increase the frequency and severity of insect outbreaks and associated wildfires, and increase the probability of establishment by invasive plant species. In the Coastal-temperate forest region snow and ice is regarded as the dominant biophysical factor. With continued warming, hydrologic changes related to more rapidly melting glaciers and rising elevation of the winter snowline will alter discharge in many rivers, which will have important consequences for terrestrial and marine ecosystem productivity. These climate-related changes will affect plant species distribution and wildlife habitat, which have regional societal consequences, and trace-gas emissions and radiation budgets, which are globally important. Our conceptual framework facilitates

  3. Evidence and implications of recent climate change in Northern Alaska and other Arctic regions

    USGS Publications Warehouse

    Hinzman, L.D.; Bettez, N.D.; Bolton, W.R.; Chapin, F.S.; Dyurgerov, M.B.; Fastie, C.L.; Griffith, B.; Hollister, R.D.; Hope, A.; Huntington, H.P.; Jensen, A.M.; Jia, G.J.; Jorgenson, T.; Kane, D.L.; Klein, D.R.; Kofinas, G.; Lynch, A.H.; Lloyd, A.H.; McGuire, A.D.; Nelson, F.E.; Oechel, W.C.; Osterkamp, T.E.; Racine, C.H.; Romanovsky, V.E.; Stone, R.S.; Stow, D.A.; Sturm, M.; Tweedie, C.E.; Vourlitis, G.L.; Walker, M.D.; Walker, D. A.; Webber, P. J.; Welker, J.M.; Winker, K.S.; Yoshikawa, K.

    2005-01-01

    The Arctic climate is changing. Permafrost is warming, hydrological processes are changing and biological and social systems are also evolving in response to these changing conditions. Knowing how the structure and function of arctic terrestrial ecosystems are responding to recent and persistent climate change is paramount to understanding the future state of the Earth system and how humans will need to adapt. Our holistic review presents a broad array of evidence that illustrates convincingly; the Arctic is undergoing a system-wide response to an altered climatic state. New extreme and seasonal surface climatic conditions are being experienced, a range of biophysical states and processes influenced by the threshold and phase change of freezing point are being altered, hydrological and biogeochemical cycles are shifting, and more regularly human sub-systems are being affected. Importantly, the patterns, magnitude and mechanisms of change have sometimes been unpredictable or difficult to isolate due to compounding factors. In almost every discipline represented, we show how the biocomplexity of the Arctic system has highlighted and challenged a paucity of integrated scientific knowledge, the lack of sustained observational and experimental time series, and the technical and logistic constraints of researching the Arctic environment. This study supports ongoing efforts to strengthen the interdisciplinarity of arctic system science and improve the coupling of large scale experimental manipulation with sustained time series observations by incorporating and integrating novel technologies, remote sensing and modeling. ?? Springer 2005.

  4. Evidence for and implications of an Early Archean terrestrial impact record

    NASA Technical Reports Server (NTRS)

    Lowe, Donald R.; Byerly, Gary R.

    1988-01-01

    Early Archean, 3.5 to 3.2 Ga, greenstone sequences in South Africa and Western Australia contain a well-preserved record of early terrestrial meteorite impacts. The main impact-produced deposits are layers, 10 cm to over 1 m thick, composed largely of sand-sized spherules, 0.1 to 4 mm in diameter. The beds studied to date show an assemblage of features indicating formation by the fall of debris from impact-generated ejecta clouds. Some presented data effectively rule out normal magmatic or sedimentary processes in the origin of these units and provide substantial support for an origin by large impacts on the early earth. The presence of at least four, remarkably thick, nearly pure spherule layers suggests that smaller-scale impact deposits may be even more abundant in these sequences. The existence of a well-preserved Archean terrestrial impact record suggests that a direct source of evidence is available regarding a number of important aspects of early earth history.

  5. Evidence and Implications of Recent Climate Change in Northern Alaska and Other Arctic Regions

    NASA Astrophysics Data System (ADS)

    Hinzman, L. D.; Bettez, N.; Bolton, W. R.; Chapin, F. S.; Dyurgerov, M. B.; Fastie, C. L.; Griffith, B.; Hollister, R. D.; Hope, A.; Huntington, H. P.; Jensen, A. M.; Jia, G. J.; Jorgenson, T.; Kane, D. L.; Klein, D. R.; Kofinas, G.; Lynch, A. H.; Lloyd, A. H.; McGuire, A. D.; Nelson, F. E.; Nolan, M.; Oechel, W. C.; Osterkamp, T. E.; Racine, C. H.; Romanovsky, V. E.; Stone, R. S.; Stow, D. A.; Sturm, M.; Tweedie, C. E.; Vourlitis, G. L.; Walker, M. D.; Walker, D. A.; Webber, P. J.; Welker, J.; Winker, K. S.; Yoshikawa, K.

    2004-12-01

    The Arctic climate is changing. Permafrost is warming, hydrological processes are changing and biological and social systems are also evolving in response to these changing conditions. Knowing how the structure and function of arctic terrestrial ecosystems are responding to recent and persistent climate change is paramount to understanding the future state of the Earth system and how humans will need to adapt. Our holistic review presents a broad array of evidence that illustrates convincingly; the Arctic is undergoing a system-wide response to an altered climatic state. New extreme and seasonal surface climatic conditions are being experienced, a range of biophysical states and processes influenced by the threshold and phase change of freezing point are being altered, hydrological and biogeochemical cycles are shifting, and more regularly human sub-systems are being affected. Importantly, the patterns, magnitude and mechanisms of change have sometimes been unpredictable or difficult to isolate due to compounding factors. In almost every discipline represented, we show how the biocomplexity of the Arctic system has highlighted and challenged a paucity of integrated scientific knowledge, the lack of sustained observational and experimental time series, and the technical and logistic constraints of researching the Arctic environment. This study supports ongoing efforts to strengthen the interdisciplinarity of arctic system science and improve the coupling of large scale experimental manipulation with sustained time series observations by incorporating and integrating novel technologies, remote sensing and modeling.

  6. Trace fossil evidence of coral-inhabiting crabs (Cryptochiridae) and its implications for growth and paleobiogeography.

    PubMed

    Klompmaker, Adiël A; Portell, Roger W; van der Meij, Sancia E T

    2016-01-01

    Members of the Cryptochiridae are small, fragile, symbiotic crabs that live in domiciles in modern corals. Despite their worldwide occurrence with over 50 species known today, their fossil record is unknown. We provide the first unambiguous evidence of cryptochirids in the fossil record through their crescentic pits, typical for certain cryptochirids, in Western Atlantic fossil corals, while the Eocene genus Montemagrechirus is excluded from the Cryptochiridae and referred to Montemagrechiridae fam. nov. Nine Pleistocene corals with crescentic pits originate from Florida (USA), and single specimens with pits come from the late Pleistocene of Cuba and the late Pliocene of Florida, all of which are measured for growth analyses. These pits represent trace fossils named Galacticus duerri igen. nov., isp. nov. A study of modern cryptochirid domicile shape (crescentic pit, circular-oval pit, or a true gall) shows that species within crab genera tend to inhabit the same pit shape. Crescentic pits in corals occur not only in the Western Atlantic today, but also in the Indo-West Pacific and in the Eastern Pacific. Thus, examination of Cenozoic fossil coral collections from these regions should yield further examples of cryptochirid pits, which would help to constrain the antiquity of this cryptic crab family. PMID:27009806

  7. Implication of the immune system in Alzheimer's disease: evidence from genome-wide pathway analysis.

    PubMed

    Lambert, Jean-Charles; Grenier-Boley, Benjamin; Chouraki, Vincent; Heath, Simon; Zelenika, Diana; Fievet, Nathalie; Hannequin, Didier; Pasquier, Florence; Hanon, Olivier; Brice, Alexis; Epelbaum, Jacques; Berr, Claudine; Dartigues, Jean-Francois; Tzourio, Christophe; Campion, Dominique; Lathrop, Mark; Amouyel, Philippe

    2010-01-01

    The results of several genome-wide association studies (GWASs) in the field of Alzheimer's disease (AD) have recently been published. Although these studies reported in detail on single-nucleotide polymorphisms (SNPs) and the neighboring genes with the strongest evidence of association with AD, little attention was paid to the rest of the genome. However, complementary statistical and bio-informatics approaches now enable the extraction of pertinent information from other SNPs and/or genes which are only nominally associated with the disease risk. Two different tools (the ALIGATOR and GenGen/KEGG software packages) were used to analyze a large GWAS dataset containing 2,032 AD cases and 5,328 controls. Convergent outputs from the two gene set enrichment approaches suggested an immune system dysfunction in AD. Furthermore, although these statistical approaches did not adopt a priori hypotheses concerning a biological function's putative role in the disease process, genes associated with AD risk were overrepresented in the "Alzheimer's disease" KEGG pathway. In conclusion, a systematic search for biological pathways using GWAS data set seems to comfort the primary causes already suspected but may specifically highlight the importance of the immune system in AD.

  8. Evidence for paleolakes in Erythraea Fossa, Mars: Implications for an ancient hydrological cycle

    NASA Astrophysics Data System (ADS)

    Buhler, Peter B.; Fassett, Caleb I.; Head, James W.; Lamb, Michael P.

    2011-05-01

    There is now widespread agreement that the surface of Mars underwent some degree of fluvial modification, but there is not yet full understanding of its surface hydrological cycle and the nature of standing bodies of water, rivers, and precipitation that affected its surface. In this paper we explore Erythraea Fossa (31.5 W, 27.3 S), a graben adjacent to Holden crater, which exhibits strong evidence that it once housed a chain of three lakes, had overland water flow, and was subject to precipitation. The inlet valley, outlet valley, and fan morphologies in the paleolakes are used to qualitatively discern the hydrologic history of the paleolakes; based on topography constraints, the three basins combined once held 56 km 3 of water. Depositional features within the basins that change with drainage area and nearby valleys that start near drainage divides indicate that the paleolakes may have been fed by precipitation driven runoff. This suggests the presence of an atmosphere, at least locally, that was capable of supporting a hydrological cycle.

  9. The implications of groundwater velocity variations on microbial transport and wellhead protection - review of field evidence.

    PubMed

    Taylor, Richard; Cronin, Aidan; Pedley, Steve; Barker, John; Atkinson, Tim

    2004-07-01

    Current strategies to protect groundwater sources from microbial contamination (e.g., wellhead protection areas) rely upon natural attenuation of microorganisms between wells or springs and potential sources of contamination and are determined using average (macroscopic) groundwater flow velocities defined by Darcy's Law. However, field studies of sewage contamination and microbial transport using deliberately applied tracers provide evidence of groundwater flow paths that permit the transport of microorganisms by rapid, statistically extreme velocities. These paths can be detected because of (i) the high concentrations of bacteria and viruses that enter near-surface environments in sewage or are deliberately applied as tracers (e.g., bacteriophage); and (ii) low detection limits of these microorganisms in water. Such paths must comprise linked microscopic pathways (sub-paths) that are biased toward high groundwater velocities. In media where microorganisms may be excluded from the matrix (pores and fissures), the disparity between the average linear velocity of groundwater flow and flow velocities transporting released or applied microorganisms is intensified. It is critical to recognise the limited protection afforded by source protection measures that disregard rapid, statistically extreme groundwater velocities transporting pathogenic microorganisms, particularly in areas dependent upon untreated groundwater supplies.

  10. Can water, sanitation and hygiene help eliminate stunting? Current evidence and policy implications.

    PubMed

    Cumming, Oliver; Cairncross, Sandy

    2016-05-01

    Stunting is a complex and enduring challenge with far-reaching consequences for those affected and society as a whole. To accelerate progress in eliminating stunting, broader efforts are needed that reach beyond the nutrition sector to tackle the underlying determinants of undernutrition. There is growing interest in how water, sanitation and hygiene (WASH) interventions might support strategies to reduce stunting in high-burden settings, such as South Asia and sub-Saharan Africa. This review article considers two broad questions: (1) can WASH interventions make a significant contribution to reducing the global prevalence of childhood stunting, and (2) how can WASH interventions be delivered to optimize their effect on stunting and accelerate progress? The evidence reviewed suggests that poor WASH conditions have a significant detrimental effect on child growth and development resulting from sustained exposure to enteric pathogens but also due to wider social and economic mechanisms. Realizing the potential of WASH to reduce stunting requires a redoubling of efforts to achieve universal access to these services as envisaged under the Sustainable Development Goals. It may also require new or modified WASH strategies that go beyond the scope of traditional interventions to specifically address exposure pathways in the first 2 years of life when the process of stunting is concentrated. PMID:27187910

  11. Trace fossil evidence of coral-inhabiting crabs (Cryptochiridae) and its implications for growth and paleobiogeography

    PubMed Central

    Klompmaker, Adiël A.; Portell, Roger W.; van der Meij, Sancia E.T.

    2016-01-01

    Members of the Cryptochiridae are small, fragile, symbiotic crabs that live in domiciles in modern corals. Despite their worldwide occurrence with over 50 species known today, their fossil record is unknown. We provide the first unambiguous evidence of cryptochirids in the fossil record through their crescentic pits, typical for certain cryptochirids, in Western Atlantic fossil corals, while the Eocene genus Montemagrechirus is excluded from the Cryptochiridae and referred to Montemagrechiridae fam. nov. Nine Pleistocene corals with crescentic pits originate from Florida (USA), and single specimens with pits come from the late Pleistocene of Cuba and the late Pliocene of Florida, all of which are measured for growth analyses. These pits represent trace fossils named Galacticus duerri igen. nov., isp. nov. A study of modern cryptochirid domicile shape (crescentic pit, circular-oval pit, or a true gall) shows that species within crab genera tend to inhabit the same pit shape. Crescentic pits in corals occur not only in the Western Atlantic today, but also in the Indo-West Pacific and in the Eastern Pacific. Thus, examination of Cenozoic fossil coral collections from these regions should yield further examples of cryptochirid pits, which would help to constrain the antiquity of this cryptic crab family. PMID:27009806

  12. Preclinical evidence implicating corticotropin-releasing factor signaling in ethanol consumption and neuroadaptation

    PubMed Central

    Phillips, T. J.; Reed, C.; Pastor, R.

    2016-01-01

    The results of many studies support the influence of the corticotropin-releasing factor (CRF) system on ethanol (EtOH) consumption and EtOH-induced neuroadaptations that are critical in the addiction process. This review summarizes the preclinical data in this area after first providing an overview of the components of the CRF system. This complex system involves hypothalamic and extra-hypothalamic mechanisms that play a role in the central and peripheral consequences of stressors, including EtOH and other drugs of abuse. In addition, several endogenous ligands and targets make up this system and show differences in their involvement in EtOH drinking and in the effects of chronic or repeated EtOH treatment. In general, genetic and pharmacological approaches paint a consistent picture of the importance of CRF signaling via type 1 CRF receptors (CRF1) in EtOH-induced neuroadaptations that result in higher levels of intake, encourage alcohol seeking during abstinence and alter EtOH sensitivity. Furthermore, genetic findings in rodents, non-human primates and humans have provided some evidence of associations of genetic polymorphisms in CRF-related genes with EtOH drinking, although additional data are needed. These results suggest that CRF1 antagonists have potential as pharmacotherapeutics for alcohol use disorders. However, given the broad and important role of these receptors in adaptation to environmental and other challenges, full antagonist effects may be too profound and consideration should be given to treatments with modulatory effects. PMID:25565358

  13. The effect of fire and permafrost interactions on soil carbon accumulation in an upland black spruce ecosystem of interior Alaska: Implications for post-thaw carbon loss

    USGS Publications Warehouse

    O'Donnell, J. A.; Harden, J.W.; McGuire, A.D.; Kanevskiy, M.Z.; Jorgenson, M.T.; Xu, X.

    2011-01-01

    High-latitude regions store large amounts of organic carbon (OC) in active-layer soils and permafrost, accounting for nearly half of the global belowground OC pool. In the boreal region, recent warming has promoted changes in the fire regime, which may exacerbate rates of permafrost thaw and alter soil OC dynamics in both organic and mineral soil. We examined how interactions between fire and permafrost govern rates of soil OC accumulation in organic horizons, mineral soil of the active layer, and near-surface permafrost in a black spruce ecosystem of interior Alaska. To estimate OC accumulation rates, we used chronosequence, radiocarbon, and modeling approaches. We also developed a simple model to track long-term changes in soil OC stocks over past fire cycles and to evaluate the response of OC stocks to future changes in the fire regime. Our chronosequence and radiocarbon data indicate that OC turnover varies with soil depth, with fastest turnover occurring in shallow organic horizons (~60 years) and slowest turnover in near-surface permafrost (>3000 years). Modeling analysis indicates that OC accumulation in organic horizons was strongly governed by carbon losses via combustion and burial of charred remains in deep organic horizons. OC accumulation in mineral soil was influenced by active layer depth, which determined the proportion of mineral OC in a thawed or frozen state and thus, determined loss rates via decomposition. Our model results suggest that future changes in fire regime will result in substantial reductions in OC stocks, largely from the deep organic horizon. Additional OC losses will result from fire-induced thawing of near-surface permafrost. From these findings, we conclude that the vulnerability of deep OC stocks to future warming is closely linked to the sensitivity of permafrost to wildfire disturbance. ?? 2010 Blackwell Publishing Ltd.

  14. Spatial gene expression analysis in tomato hypocotyls suggests cysteine as key precursor of vascular sulfur accumulation implicated in Verticillium dahliae defense.

    PubMed

    Klug, Katharina; Hogekamp, Claudia; Specht, André; Myint, San Shwe; Blöink, Dominik; Küster, Helge; Horst, Walter J

    2015-02-01

    Verticillium dahliae is a prominent generator of plant vascular wilting disease and sulfur (S)-enhanced defense (SED) mechanisms contribute to its in-planta elimination. The accumulation of S-containing defense compounds (SDCs) including elemental S (S(0) ) has been described based on the comparison of two near-isogenic tomato (Solanum lycopersicum) lines differing in fungal susceptibility. To better understand the effect of S nutrition on V. dahliae resistance both lines were supplied with low, optimal or supraoptimal sulfate-S. An absolute quantification demonstrated a most effective fungal elimination due to luxury plant S nutrition. High-pressure liquid chromatography (HPLC) showed a strong regulation of Cys levels and an S-responsive GSH pool rise in the bulk hypocotyl. High-frequency S peak accumulations were detected in vascular bundles of resistant tomato plants after fungal colonization by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). Global transcriptomic analysis suggested that early steps of the primary S metabolism did not promote the SDCs synthesis in the whole hypocotyl as gene expression was downregulated after infection. Enhanced S fertilization mostly alleviated the repressive fungal effect but did not reverse it. Upregulation of glutathione (GSH)-associated genes in bulk hypocotyls but not in vascular bundles indicated a global antioxidative role of GSH. To finally assign the contribution of S metabolism-associated genes to high S(0) accumulations exclusively found in the resistant tomato line, a spatial gene expression approach was applied. Laser microdissection of infected vascular bundles revealed a switch toward transcription of genes connected with cysteine (Cys) synthesis. The upregulation of LeOASTLp1 suggests a role for Cys as key precursor for local S accumulations (possibly S(0) ) in the vascular bundles of the V. dahliae-resistant tomato line.

  15. Simulating soil carbon accumulation in an upland black spruce ecosystem of interior Alaska: implications for permafrost carbon dynamics to climate change

    NASA Astrophysics Data System (ADS)

    Wang, X.; Yokozawa, M.; Toda, M.; Kushida, K.

    2015-12-01

    Boreal terrestrial ecosystems act as a huge reservoir of organic carbon, most of which is mainly stored in both active-layer soils and permafrost. Recently, many observational studies have revealed that ongoing climate warming has promoted changes in fire regime, which stimulates the permafrost thaw in the boreal area. Consequently, the decomposition rate of the organic and mineral soils will increase and a large amount of CO2 will be released into the atmosphere. The sustained CO2­ release from the soils may create a positive feedback in relation to carbon cycling between the atmosphere and boreal terrestrial ecosystems. However, there still remains substantial uncertainty for evaluating the mechanisms of the carbon cycle feedbacks over centuries. In the present study, we examined the effect of warming and fire episodes on soil carbon dynamics in an upland black spruce ecosystem in interior Alaska, by using a Physical and Biogeochemical Soil Dynamics Model (PB-SDM) which can simulate the feedback cycle of soil organic carbon accumulation with soil thermal and hydrological dynamics. The result indicates that soil carbon accumulation in the organic layer was strongly dominated by increased temperature. In addition, fire events by which a great number of soil layers burned contributed to decrease in soil carbon accumulation largely in the organic layer. On the other hand, remarkably increased temperature conditions (around 9.6℃ by 3000) controlled soil carbon accumulation in the mineral layer and changes in soil decomposition rate accompanying with the shift from frozen to thawed conditions with warming accelerated soil carbon decomposition. It is suggested that future climate warming would result in drastic decrease in the soil carbon stock, largely from the organic layer, whereas the vulnerability of deeper soil carbon to future warming is closely connected to permafrost degradation due to wildfire disturbance.

  16. Amyloidosis in Alzheimer's Disease: The Toxicity of Amyloid Beta (Aβ), Mechanisms of Its Accumulation and Implications of Medicinal Plants for Therapy

    PubMed Central

    2013-01-01

    Alzheimer's disease (AD) is a progressive neurodegenerative disorder that leads to memory deficits and death. While the number of individuals with AD is rising each year due to the longer life expectancy worldwide, current therapy can only somewhat relieve the symptoms of AD. There is no proven medication to cure or prevent the disease, possibly due to a lack of knowledge regarding the molecular mechanisms underlying disease pathogenesis. Most previous studies have accepted the “amyloid hypothesis,” in which the neuropathogenesis of AD is believed to be triggered by the accumulation of the toxic amyloid beta (Aβ) protein in the central nervous system (CNS). Lately, knowledge that may be critical to unraveling the hidden pathogenic pathway of AD has been revealed. This review concentrates on the toxicity of Aβ and the mechanism of accumulation of this toxic protein in the brain of individuals with AD and also summarizes recent advances in the study of these accumulation mechanisms together with the role of herbal medicines that could facilitate the development of more effective therapeutic and preventive strategies. PMID:23762130

  17. The Plasma Depletion Layer Beyond the Heliopause: Evidence, Implications, and Predictions for Voyager 2

    NASA Astrophysics Data System (ADS)

    Cairns, I. H.; Fuselier, S. A.

    2015-12-01

    A plasma depletion layer (PDL) is predicted beyond the heliopause, analogous to the PDLs observed sunwards of the magnetopauses of Earth, Mercury, Jupiter, and Saturn. The physics is that draping of interstellar (ISM) magnetic field lines over the heliopause should increase the magnetic field strength (and so the perpendicular ion temperature), cause density depletions by allowing plasma ions (and electrons) with large parallel temperatures to escape along the field, and increase the perpendicular to parallel temperature anisotropy until limited by wave instabilities. It is argued that published Voyager 1 magnetometer and plasma wave data beyond the heliopause provide strong evidence for the magnetic field amplification (by ≈ 30%) and density depletion (by ≈ 50%) expected for the PDL. The predicted reduction in parallel temperature is ≈ 50%. Using the ISM magnetic field direction obtained from the centroid of the IBEX Ribbon, the orientation of the PDL and the associated locations on the heliopause of the points of maximum magnetic field draping and maximum total pressure are predicted. It is observed that the IBEX Ribbon overlies the former while the latter lies within the ridge of maximum non-Ribbon ENA flux. The PDL should be strongest along the ISM field line passing through these points and the nominal Sun-ISM velocity vector. It is predicted that Voyager 2 lies within 5 degrees (≈ 10 AU) of the strong PDL region while Voyager 1 is over 15 degrees (≈ 35 AU) away. Thus Voyager 2 should observe a much stronger PDL (stronger magnetic field amplification, density depletions, and reductions in parallel temperature) than Voyager 1. Finally, the reduced cosmic ray fluxes observed near 90 degree pitchangle by Voyager 1 beyond the heliopause may be explained qualitatively in terms of magnetic focusing as cosmic rays propagate away from the stronger field regions of the PDL and magnetic draping region on the heliopause, assuming isotropic cosmic rays at the

  18. EVIDENCE OF LIGHT-BENDING EFFECTS AND ITS IMPLICATION FOR SPECTRAL STATE TRANSITIONS

    SciTech Connect

    Reis, R. C.; Miller, J. M.; Reynolds, M. T.; Fabian, A. C.; Walton, D. J.; Steiner, J. F.; Cackett, E.

    2013-01-20

    It has long been speculated that the nature of the hard X-ray corona may be an important second driver of black hole state transitions, in addition to the mass accretion rate through the disk. However, a clear physical picture of coronal changes has not yet emerged. We present results from a systematic analysis of Rossi X-Ray Timing Explorer observations of the stellar-mass black hole binary XTE J1650-500. All spectra with significant hard X-ray detections were fit using a self-consistent, relativistically blurred disk reflection model suited to high ionization regimes. Importantly, we find evidence that both the spectral and timing properties of black hole states may be partially driven by the height of the X-ray corona above the disk, and related changes in how gravitational light bending affects the corona-disk interaction. Specifically, the evolution of the power-law, thermal disk, and relativistically convolved reflection components in our spectral analysis indicates that: (1) the disk inner radius remains constant at r {sub in} =1.65 {+-} 0.08 GM/c {sup 2} (consistent with values found for the ISCO of XTE J1650-500 in other works) throughout the transition from the brighter phases of the low-hard state to the intermediate states (both the hard-intermediate and soft-intermediate), through to the soft state and back; (2) the ratio between the observed reflected X-ray flux and power-law continuum (the 'reflection fraction', R) increases sharply at the transition between the hard-intermediate and soft-intermediate states ('ballistic' jets are sometimes launched at this transition); (3) both the frequency and coherence of the high-frequency quasi-periodic oscillations observed in XTE J1650-500 increase with R. We discuss our results in terms of black hole states and the nature of black hole accretion flows across the mass scale.

  19. Treatment of anabolic-androgenic steroid dependence: Emerging evidence and its implications.

    PubMed

    Kanayama, Gen; Brower, Kirk J; Wood, Ruth I; Hudson, James I; Pope, Harrison G

    2010-06-01

    Currently, few users of anabolic-androgenic steroids (AAS) seek substance abuse treatment. But this picture may soon change substantially, because illicit AAS use did not become widespread until the 1980s, and consequently the older members of this AAS-using population - those who initiated AAS as youths in the 1980s - are only now reaching middle age. Members of this group, especially those who have developed AAS dependence, may therefore be entering the age of risk for cardiac and psychoneuroendocrine complications sufficient to motivate them for substance abuse treatment. We suggest that this treatment should address at least three etiologic mechanisms by which AAS dependence might develop. First, individuals with body image disorders such as "muscle dysmorphia" may become dependent on AAS for their anabolic effects; these body image disorders may respond to psychological therapies or pharmacological treatments. Second, AAS suppress the male hypothalamic-pituitary-gonadal axis via their androgenic effects, potentially causing hypogonadism during AAS withdrawal. Men experiencing prolonged dysphoric effects or frank major depression from hypogonadism may desire to resume AAS, thus contributing to AAS dependence. AAS-induced hypogonadism may require treatment with human chorionic gonadotropin or clomiphene to reactivate neuroendocrine function, and may necessitate antidepressant treatments in cases of depression inadequately responsive to endocrine therapies alone. Third, human and animal evidence indicates that AAS also possess hedonic effects, which likely promote dependence via mechanisms shared with classical addictive drugs, especially opioids. Indeed, the opioid antagonist naltrexone blocks AAS dependence in animals. By inference, pharmacological and psychosocial treatments for human opioid dependence might also benefit AAS-dependent individuals.

  20. Experimental evidence for limited vocal recognition in a wild primate: implications for the social complexity hypothesis

    PubMed Central

    Bergman, Thore J.

    2010-01-01

    Although monitoring social information is a key aspect of the social complexity hypothesis, surprisingly little work has compared social knowledge across different species of wild animals. In the present study, I use playback experiments to test for individual recognition in wild male geladas (Theropithecus gelada) to compare with published accounts of social knowledge in chacma baboons (Papio ursinus). Geladas and baboons are closely related primates living in socially complex groups that differ dramatically in group size—geladas routinely associate with more than 10 times the number of conspecifics than do baboons. Using grunts from non-rival males to simulate approaches, I examined the strength of a subject male's response when the ‘approach’ was from the direction of (i) non-rival males (control), or (ii) rival males (a more salient stimulus if playback grunts are not recognized by the subject). I compared responses separately based on the degree of social overlap between the caller and the subject. Responses indicate that male geladas, unlike baboons, do not use vocalizations to recognize all of the individuals they regularly encounter. This represents, to my knowledge, the first documented evidence of ‘missing’ social knowledge in a natural primate population. The sharp distinction between baboons and geladas suggests that geladas are either unable or unmotivated to keep track of the individual identity of other males in their multi-level society—even males with whom they have a large degree of social overlap. Thus, these results are consistent with the central assumption of the social complexity hypothesis that social cognition is costly. PMID:20462901

  1. Evidence for a Grooming Claw in a North American Adapiform Primate: Implications for Anthropoid Origins

    PubMed Central

    Maiolino, Stephanie; Boyer, Doug M.; Bloch, Jonathan I.; Gilbert, Christopher C.; Groenke, Joseph

    2012-01-01

    Among fossil primates, the Eocene adapiforms have been suggested as the closest relatives of living anthropoids (monkeys, apes, and humans). Central to this argument is the form of the second pedal digit. Extant strepsirrhines and tarsiers possess a grooming claw on this digit, while most anthropoids have a nail. While controversial, the possible presence of a nail in certain European adapiforms has been considered evidence for anthropoid affinities. Skeletons preserved well enough to test this idea have been lacking for North American adapiforms. Here, we document and quantitatively analyze, for the first time, a dentally associated skeleton of Notharctus tenebrosus from the early Eocene of Wyoming that preserves the complete bones of digit II in semi-articulation. Utilizing twelve shape variables, we compare the distal phalanges of Notharctus tenebrosus to those of extant primates that bear nails (n = 21), tegulae (n = 4), and grooming claws (n = 10), and those of non-primates that bear claws (n = 7). Quantitative analyses demonstrate that Notharctus tenebrosus possessed a grooming claw with a surprisingly well-developed apical tuft on its second pedal digit. The presence of a wide apical tuft on the pedal digit II of Notharctus tenebrosus may reflect intermediate morphology between a typical grooming claw and a nail, which is consistent with the recent hypothesis that loss of a grooming claw occurred in a clade containing adapiforms (e.g. Darwinius masillae) and anthropoids. However, a cladistic analysis including newly documented morphologies and thorough representation of characters acknowledged to have states constituting strepsirrhine, haplorhine, and anthropoid synapomorphies groups Notharctus tenebrosus and Darwinius masillae with extant strepsirrhines rather than haplorhines suggesting that the form of pedal digit II reflects substantial homoplasy during the course of early primate evolution. PMID:22253707

  2. Evidence for a composite organic-inorganic fabric of belemnite rostra: Implications for palaeoceanography and palaeoecology

    NASA Astrophysics Data System (ADS)

    Hoffmann, R.; Richter, D. K.; Neuser, R. D.; Jöns, N.; Linzmeier, B. J.; Lemanis, R. E.; Fusseis, F.; Xiao, X.; Immenhauser, A.

    2016-07-01

    Carbonate skeletons of fossil marine organisms are widely used to reconstruct palaeoceanographic parameters. Specifically, the geochemistry of Jurassic and Cretaceous belemnite rostra is traditionally interpreted to represent near sea-surface seawater properties. More recently, an increasing number of workers, have reported significant scatter in geochemical data (e.g., δ18O, δ13C, element/Ca ratio) when comparing rostra from the same stratigraphic level or within a single belemnite rostrum. This scatter is not explained by differential diagenetic overprint alone. Here we report petrographic evidence on the primary ultrastructure of rostra of Megateuthis (Middle Jurassic) and Belemnitella and Gonioteuthis (Late Cretaceous). The biogenic ultrastructure consists of a filigree framework of triaxial branches and tetrahedrons of variable size forming a honeycomb-like network. Data presented here suggest that these rostra yielded as much as 50 to 90% primary pore space. On the level of a working hypothesis - and in analogy with modern cephalopods - we propose that the pore space was formerly filled with body fluid and/or organic compounds during the life time of these organisms. Intra-rostral porosity was post mortem occluded by earliest diagenetic isopachous calcite cements of a non-biogenic origin. These may have been precipitated due to increased alkalinity related to the decay of organic matter. If this holds true, then the resulting fabric represents a composite biogenic/abiogenic structure. In order to optically separate the two calcite phases forming a single calcite fibre, we employed a wide range of state-of-the-art analytical tools to thin sections and ultra-thin sections of well-preserved specimens. Pending a verification of these well-supported ultrastructural data by means of high-resolution geochemical analyses from biogenic and abiogenic phases, we suggest that these findings have significance for those using belemnite rostra as archives of their

  3. Further evidence implicating prostaglandin E sub 2 in the genesis of pyrogen fever

    SciTech Connect

    Coceani, F.; Lees, J.; Bishai, I. )

    1988-03-01

    Conscious cats were used to study the effects of endotoxin and interleukin 1 (IL 1) on levels of prostaglandin (PG) E{sub 2} and thromboxane (TX) B{sub 2} (the stable TXA{sub 2} byproduct) in cerebrospinal fluid (CSF) from the third ventricle. Pyrogens were given intravenously or intraventricularly and prostanoids were measured by radioimmunoassay. PGE{sub 2} was normally less abundant than TXB{sub 2}, and its level increased severalfold during the sustained fever following intravenous endotoxin (bolus) or IL 1 (bolus plus infusion). PGE{sub 2} elevation preceded the fever and was maintained thereafter. Likewise, intraventricular pyrogens promoted PGE{sub 2} formation, and their effect was also manifest during the latent period of the fever. The PGE{sub 2} metabolite, 13,14-dihydro-15-keto-PGE{sub 2}, was not measurable in CSF from either afebrile or febrile animals. Basal content of PGE{sub 2}, on the other hand, was higher in animals pretreated with probenecid, confirming the importance of transport processes in removing prostanoids from brain. Unlike PGE{sub 2}, TXB{sub 2} levels did not change during the fever to intravenous endotoxin. TXB{sub 2} rose instead in response to intraventricular endotoxin, although the elevation did not extend beyond fever uprise. Furthermore, a TXA{sub 2} analog had inconsistent effects on body temperature, while a TXA{sub 2} antagonist did not interfere with endotoxin fever. These findings strongly support a causative role for PGE{sub 2} in the onset and progression of pyrogen fever. No evidence of a similar role was obtained for TXA{sub 2}.

  4. Evidence for a grooming claw in a North American adapiform primate: implications for anthropoid origins.

    PubMed

    Maiolino, Stephanie; Boyer, Doug M; Bloch, Jonathan I; Gilbert, Christopher C; Groenke, Joseph

    2012-01-01

    Among fossil primates, the Eocene adapiforms have been suggested as the closest relatives of living anthropoids (monkeys, apes, and humans). Central to this argument is the form of the second pedal digit. Extant strepsirrhines and tarsiers possess a grooming claw on this digit, while most anthropoids have a nail. While controversial, the possible presence of a nail in certain European adapiforms has been considered evidence for anthropoid affinities. Skeletons preserved well enough to test this idea have been lacking for North American adapiforms. Here, we document and quantitatively analyze, for the first time, a dentally associated skeleton of Notharctus tenebrosus from the early Eocene of Wyoming that preserves the complete bones of digit II in semi-articulation. Utilizing twelve shape variables, we compare the distal phalanges of Notharctus tenebrosus to those of extant primates that bear nails (n = 21), tegulae (n = 4), and grooming claws (n = 10), and those of non-primates that bear claws (n = 7). Quantitative analyses demonstrate that Notharctus tenebrosus possessed a grooming claw with a surprisingly well-developed apical tuft on its second pedal digit. The presence of a wide apical tuft on the pedal digit II of Notharctus tenebrosus may reflect intermediate morphology between a typical grooming claw and a nail, which is consistent with the recent hypothesis that loss of a grooming claw occurred in a clade containing adapiforms (e.g. Darwinius masillae) and anthropoids. However, a cladistic analysis including newly documented morphologies and thorough representation of characters acknowledged to have states constituting strepsirrhine, haplorhine, and anthropoid synapomorphies groups Notharctus tenebrosus and Darwinius masillae with extant strepsirrhines rather than haplorhines suggesting that the form of pedal digit II reflects substantial homoplasy during the course of early primate evolution.

  5. Chagas disease in Texas: recognizing the significance and implications of evidence in the literature.

    PubMed

    Hanford, Elaine Jennifer; Zhan, F Benjamin; Lu, Yongmei; Giordano, Alberto

    2007-07-01

    Chagas disease is endemic and is recognized as a major health problem in many Latin American countries. Despite the parallels between socio-economic and environmental conditions in Texas and much of Latin America, Chagas disease is not a notifiable human disease in Texas. Based on extensive review of related literature, this paper seeks to recognize the evidence that Chagas Disease is endemic to Texas but the epidemiological, parasitological and entomological patterns of Chagas disease in Texas are both different from and parallel to other endemic regions. We find that with a growing immigrant human reservoir, the epidemiological differences may be reduced and result in increasing incidence of the disease. Chagas disease should be recognized as an emerging disease among both immigrant and indigenous populations. Without proper actions, Chagas disease will place increasing burden on the health care system. Current medical treatments consist of chemotherapies that carry the risk of serious side effects; curing the potentially fatal disease remains equivocal. Therefore, as shown in South America, prevention is paramount and can be successfully achieved through intervention and education. We conclude that biogeographical research is needed to (1) distinguish the dynamic evolution of the agent-vector-host system, (2) document locations with greater risk and identify mechanisms responsible for observed changes in risk, and (3) assist in developing a model for Triatomid vector-borne disease in states like Texas where the disease is both endemic and may be carried by a sizeable immigrant population. Tracking of Chagas disease and planning for appropriate health care services would also be aided by including Chagas disease on the list of reportable diseases for humans.

  6. Topical calcineurin inhibitors and lymphoma risk: evidence update with implications for daily practice.

    PubMed

    Siegfried, Elaine C; Jaworski, Jennifer C; Hebert, Adelaide A

    2013-06-01

    Topical calcineurin inhibitors (TCIs), commercially available since 2000-2001, are the first and only topical medications approved for chronic treatment of atopic dermatitis (AD) in pediatric patients and remain a welcomed alternative to topical corticosteroids. In January 2006, the US Food and Drug Administration (FDA) issued a boxed warning requirement based on a theoretical risk of malignancy (including lymphoma) with TCI use. However, in the years since, analyses of epidemiologic and clinical data have failed to demonstrate a causal relationship between TCI use and malignancy or lymphoma risk, especially for pimecrolimus cream. In fact, the observed number of malignancies and lymphomas observed both in post-marketing surveillance and reported to the FDA using its adverse events reporting system is much lower among TCI-exposed patients than the expected number for the general population. Furthermore, among children enrolled in post-marketing pediatric registry studies for both tacrolimus and pimecrolimus followed for up to 5.5 years [10,724 patient-years (PY)] or 6.5 years (16,219 PY), respectively, the observed number of malignancies and lymphomas is very low and similar to the number expected for a sample of similar size in the general population. In addition to reporting these comparative malignancy and lymphoma data, this article provides a historical overview of the boxed warning requirement and critically evaluates the preclinical, clinical, and epidemiological evidence that has thus far failed to substantiate a relationship between TCI use and malignancy. The authors also provide practical clinical advice for optimizing AD management and patient care in the context of the boxed warning. PMID:23703374

  7. Substance abuse interventions for parents involved in the child welfare system: evidence and implications.

    PubMed

    Osterling, Kathy Lemon; Austin, Michael J

    2008-01-01

    As child welfare systems across the country face the problem of parental substance abuse, there is an increasing need to understand the types of treatment approaches that are most effective for substance-abusing parents in the child welfare system-the majority of whom are mothers. This structured review of the literature focuses on evidence related to two areas: (1) individual-level interventions designed to assist mothers and women in addressing their substance abuse problems, and (2) system-level interventions designed to improve collaboration and coordination between the child welfare system and the alcohol and other drug system. Overall, research suggests the following program components may be effective with substance-abusing women with children: (1) Women-centered treatment that involves children, (2) Specialized health and mental health services, (3) Home visitation services, (4) Concrete assistance, (5) Short-term targeted interventions, and (6) Comprehensive programs that integrate many of these components. Research also suggests that promising collaborative models between the child welfare system (CWS) and the alcohol and other drug (AOD) system typically include the following core elements: (1) Out-stationing AOD workers in child welfare offices, (2) Joint case planning, (3) Using official committees to guide collaborative efforts, (4) Training and cross-training, (5) Using protocols for sharing confidential information, and (6) Using dependency drug courts. Although more rigorous research is needed on both individual-level and system-level substance abuse interventions for parents involved in the child welfare system, the integration of individual-level interventions and system-level approaches is a potentially useful practice approach with this vulnerable population.

  8. Evidence for a Hadean to Paleoarchean geodynamo: Implications for the survivability of planetary hydrospheres

    NASA Astrophysics Data System (ADS)

    Tarduno, J. A.; Cottrell, R. D.; Bono, R. K.; Dare, M. S.

    2015-12-01

    Knowledge of when the geodynamo started is important for understanding the evolution of the atmosphere and life on Earth. Full vector paleointensity measurements of Archean to Hadean zircons bearing magnetic inclusions from the Jack Hills conglomerate (Western Australia) allow a for reconstruction of the early history of the geodynamo (Tarduno et al., 2015). Data from zircons between 3.3 and 4.2 billion-years-old record magnetic fields varying between 1.0 and 0.12 times recent equatorial field strengths. These magnetizations can only be read using highly sensitive cryogenic magnetometers such as the ultra-high resolution 3-component DC SQUID small bore magnetometer at the University of Rochester. The direct measurement of each component of magnetization separates this class of magnetometer from one-axis instruments that have an inherent limitation due to non-uniqueness. Only a few laboratories have instrumentation/procedures with the resolution to accurately record directions and paleointensities (see presentations by Dare et al., 2015, and Cottrell et al., 2015). For example, data from Weiss et al. (2015) are too noisy to examine Paleoarchean to Hadean magnetic fields. In contrast, our high-resolution paleointensity and age data suggest the presence of a terrestrial core dynamo more than 750 million years earlier than prior estimates. This early start for the geodynamo is similar to that suggested for the early Martian magnetic field. However, the subsequent collapse of the Martian dynamo probably facilitated atmospheric stripping. In contrast, the early start and persistence of atmospheric shielding associated with the long-lived geodynamo was likely a key factor in the development of Earth as a habitable planet. Paleomagnetic evidence for these ancient magnetic fields will be discussed as will the role of planetary magnetic shielding.

  9. Treatment of anabolic-androgenic steroid dependence: Emerging evidence and its implications.

    PubMed

    Kanayama, Gen; Brower, Kirk J; Wood, Ruth I; Hudson, James I; Pope, Harrison G

    2010-06-01

    Currently, few users of anabolic-androgenic steroids (AAS) seek substance abuse treatment. But this picture may soon change substantially, because illicit AAS use did not become widespread until the 1980s, and consequently the older members of this AAS-using population - those who initiated AAS as youths in the 1980s - are only now reaching middle age. Members of this group, especially those who have developed AAS dependence, may therefore be entering the age of risk for cardiac and psychoneuroendocrine complications sufficient to motivate them for substance abuse treatment. We suggest that this treatment should address at least three etiologic mechanisms by which AAS dependence might develop. First, individuals with body image disorders such as "muscle dysmorphia" may become dependent on AAS for their anabolic effects; these body image disorders may respond to psychological therapies or pharmacological treatments. Second, AAS suppress the male hypothalamic-pituitary-gonadal axis via their androgenic effects, potentially causing hypogonadism during AAS withdrawal. Men experiencing prolonged dysphoric effects or frank major depression from hypogonadism may desire to resume AAS, thus contributing to AAS dependence. AAS-induced hypogonadism may require treatment with human chorionic gonadotropin or clomiphene to reactivate neuroendocrine function, and may necessitate antidepressant treatments in cases of depression inadequately responsive to endocrine therapies alone. Third, human and animal evidence indicates that AAS also possess hedonic effects, which likely promote dependence via mechanisms shared with classical addictive drugs, especially opioids. Indeed, the opioid antagonist naltrexone blocks AAS dependence in animals. By inference, pharmacological and psychosocial treatments for human opioid dependence might also benefit AAS-dependent individuals. PMID:20188494

  10. Geophysical evidence for melt in the deep lunar interior and implications for lunar evolution

    NASA Astrophysics Data System (ADS)

    Khan, A.; Connolly, J. A. D.; Pommier, A.; Noir, J.

    2014-10-01

    Analysis of lunar laser ranging and seismic data has yielded evidence that has been interpreted to indicate a molten zone in the lowermost mantle overlying a fluid core. Such a zone provides strong constraints on models of lunar thermal evolution. Here we determine thermochemical and physical structure of the deep Moon by inverting lunar geophysical data (mean mass and moment of inertia, tidal Love number, and electromagnetic sounding data) in combination with phase-equilibrium computations. Specifically, we assess whether a molten layer is required by the geophysical data. The main conclusion drawn from this study is that a region with high dissipation located deep within the Moon is required to explain the geophysical data. This region is located within the mantle where the solidus is crossed at a depth of ˜1200 km (≥1600°C). Inverted compositions for the partially molten layer (150-200 km thick) are enriched in FeO and TiO2 relative to the surrounding mantle. The melt phase is neutrally buoyant at pressures of ˜4.5-4.6 GPa but contains less TiO2 (<15 wt %) than the Ti-rich (˜16 wt %) melts that produced a set of high-density primitive lunar magmas (density of 3.4 g/cm3). Melt densities computed here range from 3.25 to 3.45 g/cm3 bracketing the density of lunar magmas with moderate-to-high TiO2 contents. Our results are consistent with a model of lunar evolution in which the cumulate pile formed from crystallization of the magma ocean as it overturned, trapping heat-producing elements in the lower mantle.

  11. The search for early markers of plague: evidence for accumulation of soluble Yersinia pestis LcrV in bubonic and pneumonic mouse models of disease.

    PubMed

    Flashner, Yehuda; Fisher, Morly; Tidhar, Avital; Mechaly, Adva; Gur, David; Halperin, Gideon; Zahavy, Eran; Mamroud, Emanuelle; Cohen, Sara

    2010-07-01

    Markers of the early stages of plague, a rapidly progressing deadly disease, are crucial for enabling the onset of an effective treatment. Here, we show that V-antigen protein (LcrV) is accumulated in the serum of Yersinia pestis-infected mice before bacterial colonization of the spleen and dissemination to blood, in a model of bubonic plague. LcrV accumulation is detected earlier than that of F1 capsular antigen, an established marker of disease. In a mouse model of pneumonic plague, LcrV can be determined in the bronchoalveolar lavage fluid somewhat later than F1, but before dissemination of Y. pestis to the blood. Thus, determination of soluble LcrV is suggested as a potential useful tool for monitoring disease progression in both bubonic and pneumonic plague. Moreover, it may be of particular advantage in cases of infections with F1 nonproducing strains.

  12. Regulation of myofibrillar accumulation in chick muscle cultures - Evidence for the involvement of calcium and lysosomes in non-uniform turnover of contractile proteins

    NASA Technical Reports Server (NTRS)

    Silver, Geri; Etlinger, Joseph D.

    1985-01-01

    The effects of calcium on the synthesis and the degradation of individual myofibrillar proteins were investigated using primary chick-leg skeletal muscle cultures labeled with S-35-methionine (for protein accumulation experiments) or Ca(2+)-45 (for calcium efflux experiments). It was found that the turnover of individual contractile proteins is regulated nonuniformly by a calcium-dependent mechanism involving lysosomes. The results also indicate that contractile proteins are released from the myofibril before their breakdown to amino acids.

  13. Evidence for and implications of self-healing pulses of slip in earthquake rupture

    USGS Publications Warehouse

    Heaton, T.H.

    1990-01-01

    Dislocation time histories of models derived from waveforms of seven earthquakes are discussed. In each model, dislocation rise times (the duration of slip for a given point on the fault) are found to be short compared to the overall duration of the earthquake (??? 10%). However, in many crack-like numerical models of dynamic rupture, the slip duration at a given point is comparable to the overall duration of the rupture; i.e. slip at a given point continues until information is received that the rupture has stopped propagating. Alternative explanations for the discrepancy between the short slip durations used to model waveforms and the long slip durations inferred from dynamic crack models are: (1) the dislocation models are unable to resolve the relatively slow parts of earthquake slip and have seriously underestimated the dislocations for these earthquakes; (2) earthquakes are composed of a sequence of small-dimension (short duration) events that are separated by locked regions (barriers); (3) rupture occurs in a narrow self-healing pulse of slip that travels along the fault surface. Evidence is discussed that suggests that slip durations are indeed short and that the self-healing slip-pulse model is the most appropriate explanation. A qualitative model is presented that produces self-healing slip pulses. The key feature of the model is the assumption that friction on the fault surface is inversely related to the local slip velocity. The model has the following features: high static strength of materials (kilobar range), low static stress drops (in the range of tens of bars), and relatively low frictional stress during slip (less than several hundreds of bars). It is suggested that the reason that the average dislocation scales with fault length is because large-amplitude slip pulses are difficult to stop and hence tend to propagate large distances. This model may explain why seismicity and ambient stress are low along fault segments that have experienced large

  14. Migration of the Antarctic Polar Front through the mid-Pleistocene transition: evidence and climatic implications

    NASA Astrophysics Data System (ADS)

    Kemp, A. E. S.; Grigorov, I.; Pearce, R. B.; Naveira Garabato, A. C.

    2010-08-01

    The Antarctic Polar Front is an important biogeochemical divider in the Southern Ocean. Laminated diatom mat deposits record episodes of massive flux of the diatom Thalassiothrix antarctica beneath the Antarctic Polar Front and provide a marker for tracking the migration of the Front through time. Ocean Drilling Program Sites 1091, 1093 and 1094 are the only deep piston cored record hitherto sampled from the sediments of the circumpolar biogenic opal belt. Mapping of diatom mat deposits between these sites indicates a glacial-interglacial front migration of up to 6 degrees of latitude in the early/mid Pleistocene. The mid-Pleistocene transition marks a stepwise minimum 7° northward migration of the locus of the Polar Front sustained for about 450 kyr until an abrupt southward return to a locus similar to its modern position and further south than any mid-Pleistocene locus. This interval from a "900 ka event" that saw major cooling of the oceans and a δ 13C minimum through to the 424 ka Mid-Brunhes Event at Termination V is also seemingly characterised by 1) sustained decreased carbonate in the sub-tropical south Atlantic, 2) reduced strength of Antarctic deep meridional circulation, 3) lower interglacial temperatures and lower interglacial atmospheric CO 2 levels (by some 30 per mil) than those of the last 400 kyr, evidencing less complete deglaciation. This evidence is consistent with a prolonged period lasting 450 kyr of only partial ventilation of the deep ocean during interglacials and suggests that the mechanisms highlighted by recent hypotheses linking mid-latitude atmospheric conditions to the extent of deep ocean ventilation and carbon sequestration over glacial-interglacial cycles are likely in operation during the longer time scale characteristic of the mid-Pleistocene transition. The cooling that initiated the "900 ka event" may have been driven by minima in insolation amplitude related to eccentricity modulation of precession that also affected low

  15. Heat accumulator

    SciTech Connect

    Bracht, A.

    1981-09-29

    A heat accumulator comprises a thermally-insulated reservoir full of paraffin wax mixture or other flowable or meltable heat storage mass, heat-exchangers immersed in the mass, a heat-trap connected to one of the heat-exchangers, and a heat user connected to the other heat-exchanger. Pumps circulate fluids through the heat-trap and the heat-using means and the respective heat-exchangers, and a stirrer agitates and circulates the mass, and the pumps and the stirrer and electric motors driving these devices are all immersed in the mass.

  16. Chimpanzee accumulative stone throwing.

    PubMed

    Kühl, Hjalmar S; Kalan, Ammie K; Arandjelovic, Mimi; Aubert, Floris; D'Auvergne, Lucy; Goedmakers, Annemarie; Jones, Sorrel; Kehoe, Laura; Regnaut, Sebastien; Tickle, Alexander; Ton, Els; van Schijndel, Joost; Abwe, Ekwoge E; Angedakin, Samuel; Agbor, Anthony; Ayimisin, Emmanuel Ayuk; Bailey, Emma; Bessone, Mattia; Bonnet, Matthieu; Brazolla, Gregory; Buh, Valentine Ebua; Chancellor, Rebecca; Cipoletta, Chloe; Cohen, Heather; Corogenes, Katherine; Coupland, Charlotte; Curran, Bryan; Deschner, Tobias; Dierks, Karsten; Dieguez, Paula; Dilambaka, Emmanuel; Diotoh, Orume; Dowd, Dervla; Dunn, Andrew; Eshuis, Henk; Fernandez, Rumen; Ginath, Yisa; Hart, John; Hedwig, Daniela; Ter Heegde, Martijn; Hicks, Thurston Cleveland; Imong, Inaoyom; Jeffery, Kathryn J; Junker, Jessica; Kadam, Parag; Kambi, Mohamed; Kienast, Ivonne; Kujirakwinja, Deo; Langergraber, Kevin; Lapeyre, Vincent; Lapuente, Juan; Lee, Kevin; Leinert, Vera; Meier, Amelia; Maretti, Giovanna; Marrocoli, Sergio; Mbi, Tanyi Julius; Mihindou, Vianet; Moebius, Yasmin; Morgan, David; Morgan, Bethan; Mulindahabi, Felix; Murai, Mizuki; Niyigabae, Protais; Normand, Emma; Ntare, Nicolas; Ormsby, Lucy Jayne; Piel, Alex; Pruetz, Jill; Rundus, Aaron; Sanz, Crickette; Sommer, Volker; Stewart, Fiona; Tagg, Nikki; Vanleeuwe, Hilde; Vergnes, Virginie; Willie, Jacob; Wittig, Roman M; Zuberbuehler, Klaus; Boesch, Christophe

    2016-01-01

    The study of the archaeological remains of fossil hominins must rely on reconstructions to elucidate the behaviour that may have resulted in particular stone tools and their accumulation. Comparatively, stone tool use among living primates has illuminated behaviours that are also amenable to archaeological examination, permitting direct observations of the behaviour leading to artefacts and their assemblages to be incorporated. Here, we describe newly discovered stone tool-use behaviour and stone accumulation sites in wild chimpanzees reminiscent of human cairns. In addition to data from 17 mid- to long-term chimpanzee research sites, we sampled a further 34 Pan troglodytes communities. We found four populations in West Africa where chimpanzees habitually bang and throw rocks against trees, or toss them into tree cavities, resulting in conspicuous stone accumulations at these sites. This represents the first record of repeated observations of individual chimpanzees exhibiting stone tool use for a purpose other than extractive foraging at what appear to be targeted trees. The ritualized behavioural display and collection of artefacts at particular locations observed in chimpanzee accumulative stone throwing may have implications for the inferences that can be drawn from archaeological stone assemblages and the origins of ritual sites.

  17. Chimpanzee accumulative stone throwing

    PubMed Central

    Kühl, Hjalmar S.; Kalan, Ammie K.; Arandjelovic, Mimi; Aubert, Floris; D’Auvergne, Lucy; Goedmakers, Annemarie; Jones, Sorrel; Kehoe, Laura; Regnaut, Sebastien; Tickle, Alexander; Ton, Els; van Schijndel, Joost; Abwe, Ekwoge E.; Angedakin, Samuel; Agbor, Anthony; Ayimisin, Emmanuel Ayuk; Bailey, Emma; Bessone, Mattia; Bonnet, Matthieu; Brazolla, Gregory; Buh, Valentine Ebua; Chancellor, Rebecca; Cipoletta, Chloe; Cohen, Heather; Corogenes, Katherine; Coupland, Charlotte; Curran, Bryan; Deschner, Tobias; Dierks, Karsten; Dieguez, Paula; Dilambaka, Emmanuel; Diotoh, Orume; Dowd, Dervla; Dunn, Andrew; Eshuis, Henk; Fernandez, Rumen; Ginath, Yisa; Hart, John; Hedwig, Daniela; Ter Heegde, Martijn; Hicks, Thurston Cleveland; Imong, Inaoyom; Jeffery, Kathryn J.; Junker, Jessica; Kadam, Parag; Kambi, Mohamed; Kienast, Ivonne; Kujirakwinja, Deo; Langergraber, Kevin; Lapeyre, Vincent; Lapuente, Juan; Lee, Kevin; Leinert, Vera; Meier, Amelia; Maretti, Giovanna; Marrocoli, Sergio; Mbi, Tanyi Julius; Mihindou, Vianet; Moebius, Yasmin; Morgan, David; Morgan, Bethan; Mulindahabi, Felix; Murai, Mizuki; Niyigabae, Protais; Normand, Emma; Ntare, Nicolas; Ormsby, Lucy Jayne; Piel, Alex; Pruetz, Jill; Rundus, Aaron; Sanz, Crickette; Sommer, Volker; Stewart, Fiona; Tagg, Nikki; Vanleeuwe, Hilde; Vergnes, Virginie; Willie, Jacob; Wittig, Roman M.; Zuberbuehler, Klaus; Boesch, Christophe

    2016-01-01

    The study of the archaeological remains of fossil hominins must rely on reconstructions to elucidate the behaviour that may have resulted in particular stone tools and their accumulation. Comparatively, stone tool use among living primates has illuminated behaviours that are also amenable to archaeological examination, permitting direct observations of the behaviour leading to artefacts and their assemblages to be incorporated. Here, we describe newly discovered stone tool-use behaviour and stone accumulation sites in wild chimpanzees reminiscent of human cairns. In addition to data from 17 mid- to long-term chimpanzee research sites, we sampled a further 34 Pan troglodytes communities. We found four populations in West Africa where chimpanzees habitually bang and throw rocks against trees, or toss them into tree cavities, resulting in conspicuous stone accumulations at these sites. This represents the first record of repeated observations of individual chimpanzees exhibiting stone tool use for a purpose other than extractive foraging at what appear to be targeted trees. The ritualized behavioural display and collection of artefacts at particular locations observed in chimpanzee accumulative stone throwing may have implications for the inferences that can be drawn from archaeological stone assemblages and the origins of ritual sites. PMID:26923684

  18. Chimpanzee accumulative stone throwing.

    PubMed

    Kühl, Hjalmar S; Kalan, Ammie K; Arandjelovic, Mimi; Aubert, Floris; D'Auvergne, Lucy; Goedmakers, Annemarie; Jones, Sorrel; Kehoe, Laura; Regnaut, Sebastien; Tickle, Alexander; Ton, Els; van Schijndel, Joost; Abwe, Ekwoge E; Angedakin, Samuel; Agbor, Anthony; Ayimisin, Emmanuel Ayuk; Bailey, Emma; Bessone, Mattia; Bonnet, Matthieu; Brazolla, Gregory; Buh, Valentine Ebua; Chancellor, Rebecca; Cipoletta, Chloe; Cohen, Heather; Corogenes, Katherine; Coupland, Charlotte; Curran, Bryan; Deschner, Tobias; Dierks, Karsten; Dieguez, Paula; Dilambaka, Emmanuel; Diotoh, Orume; Dowd, Dervla; Dunn, Andrew; Eshuis, Henk; Fernandez, Rumen; Ginath, Yisa; Hart, John; Hedwig, Daniela; Ter Heegde, Martijn; Hicks, Thurston Cleveland; Imong, Inaoyom; Jeffery, Kathryn J; Junker, Jessica; Kadam, Parag; Kambi, Mohamed; Kienast, Ivonne; Kujirakwinja, Deo; Langergraber, Kevin; Lapeyre, Vincent; Lapuente, Juan; Lee, Kevin; Leinert, Vera; Meier, Amelia; Maretti, Giovanna; Marrocoli, Sergio; Mbi, Tanyi Julius; Mihindou, Vianet; Moebius, Yasmin; Morgan, David; Morgan, Bethan; Mulindahabi, Felix; Murai, Mizuki; Niyigabae, Protais; Normand, Emma; Ntare, Nicolas; Ormsby, Lucy Jayne; Piel, Alex; Pruetz, Jill; Rundus, Aaron; Sanz, Crickette; Sommer, Volker; Stewart, Fiona; Tagg, Nikki; Vanleeuwe, Hilde; Vergnes, Virginie; Willie, Jacob; Wittig, Roman M; Zuberbuehler, Klaus; Boesch, Christophe

    2016-01-01

    The study of the archaeological remains of fossil hominins must rely on reconstructions to elucidate the behaviour that may have resulted in particular stone tools and their accumulation. Comparatively, stone tool use among living primates has illuminated behaviours that are also amenable to archaeological examination, permitting direct observations of the behaviour leading to artefacts and their assemblages to be incorporated. Here, we describe newly discovered stone tool-use behaviour and stone accumulation sites in wild chimpanzees reminiscent of human cairns. In addition to data from 17 mid- to long-term chimpanzee research sites, we sampled a further 34 Pan troglodytes communities. We found four populations in West Africa where chimpanzees habitually bang and throw rocks against trees, or toss them into tree cavities, resulting in conspicuous stone accumulations at these sites. This represents the first record of repeated observations of individual chimpanzees exhibiting stone tool use for a purpose other than extractive foraging at what appear to be targeted trees. The ritualized behavioural display and collection of artefacts at particular locations observed in chimpanzee accumulative stone throwing may have implications for the inferences that can be drawn from archaeological stone assemblages and the origins of ritual sites. PMID:26923684

  19. Vitamin D and Physical Activity in Patients With Colorectal Cancer: Epidemiological Evidence and Therapeutic Implications.

    PubMed

    Morales-Oyarvide, Vicente; Meyerhardt, Jeffrey A; Ng, Kimmie

    2016-01-01

    Colorectal cancer (CRC) is a leading cause of cancer incidence and mortality in the United States. Notwithstanding major improvements in the early detection and treatment of CRC, an important proportion of patients who received a diagnosis of localized disease ultimately have a recurrence and die, underscoring the need of new therapeutic approaches. Vitamin D and physical activity (PA) have emerged as 2 potential interventions for both prevention and treatment of CRC. Plausible biological mechanisms have been described for the antineoplastic effects of vitamin D and PA, and a wealth of epidemiological evidence indicates that 25(OH)D (the main circulating form of vitamin D) and PA levels are inversely associated with CRC risk. Recent efforts have now focused on the role of vitamin D and PA as adjunct treatments after a CRC diagnosis. Observational studies evaluating prediagnosis and postdiagnosis circulating 25(OH)D levels among patients with CRC of all stages have found that subjects with levels in the highest quantiles have improved overall and CRC-specific survival compared with those with levels in the lowest quantiles. Similarly, prospective studies of PA have found that higher levels of postdiagnosis PA are associated with lower overall and CRC-specific mortality in patients with nonmetastatic CRC. Meta-analyses of the observational studies of 25(OH)D and postdiagnosis PA have confirmed significant protective associations against overall and CRC-specific mortality, as well as significant dose-response relationships. No randomized controlled trial of vitamin D or PA using survival outcomes as endpoints has been completed to date. Two randomized, placebo-controlled trials of vitamin D in patients with metastatic CRC assessing patient survival as an endpoint are underway: the first is a phase II trial comparing high-dose vitamin D3 (8000 IU/d for 2 weeks followed by 4000 IU/d) versus standard dose (400 IU/d), and the second is a phase I-II trial comparing

  20. Differentially expressed galactinol synthase(s) in chickpea are implicated in seed vigor and longevity by limiting the age induced ROS accumulation

    PubMed Central

    Salvi, Prafull; Saxena, Saurabh Chandra; Petla, Bhanu Prakash; Kamble, Nitin Uttam; Kaur, Harmeet; Verma, Pooja; Rao, Venkateswara; Ghosh, Shraboni; Majee, Manoj

    2016-01-01

    Galactinol synthase (GolS) catalyzes the first and rate limiting step of Raffinose Family Oligosaccharide (RFO) biosynthetic pathway, which is a highly specialized metabolic event in plants. Increased accumulation of galactinol and RFOs in seeds have been reported in few plant species, however their precise role in seed vigor and longevity remain elusive. In present study, we have shown that galactinol synthase activity as well as galactinol and raffinose content progressively increase as seed development proceeds and become highly abundant in pod and mature dry seeds, which gradually decline as seed germination progresses in chickpea (Cicer arietinum). Furthermore, artificial aging also stimulates galactinol synthase activity and consequent galactinol and raffinose accumulation in seed. Molecular analysis revealed that GolS in chickpea are encoded by two divergent genes (CaGolS1 and CaGolS2) which potentially encode five CaGolS isoforms through alternative splicing. Biochemical analysis showed that only two isoforms (CaGolS1 and CaGolS2) are biochemically active with similar yet distinct biochemical properties. CaGolS1 and CaGolS2 are differentially regulated in different organs, during seed development and germination however exhibit similar subcellular localization. Furthermore, seed-specific overexpression of CaGolS1 and CaGolS2 in Arabidopsis results improved seed vigor and longevity through limiting the age induced excess ROS and consequent lipid peroxidation. PMID:27725707

  1. Increased growth and root Cu accumulation of Sorghum sudanense by endophytic Enterobacter sp. K3-2: Implications for Sorghum sudanense biomass production and phytostabilization.

    PubMed

    Li, Ya; Wang, Qi; Wang, Lu; He, Lin-Yan; Sheng, Xia-Fang

    2016-02-01

    Endophytic bacterial strain K3-2 was isolated from the roots of Sorghum sudanense (an bioenergy plant) grown in a Cu mine wasteland soils and characterized. Strain K3-2 was identified as Enterobacter sp. based on 16S rRNA gene sequence analysis. Strain K3-2 exhibited Cu resistance and produced 1-aminocyclopropane-1-carboxylate (ACC) deaminase, indole-3-acetic acid (IAA), siderophores, and arginine decarboxylase. Pot experiments showed that strain K3-2 significantly increased the dry weight and root Cu accumulation of Sorghum sudanense grown in the Cu mine wasteland soils. Furthermore, increase in total Cu uptake (ranging from 49% to 95%) of the bacterial inoculated-Sorghum sudanense was observed compared to the control. Notably, most of Cu (83-86%) was accumulated in the roots of Sorghum sudanense. Furthermore, inoculation with strain K3-2 was found to significantly increase Cu bioconcentration factors and the proportions of IAA- and siderophore-producing bacteria in the root interiors and rhizosphere soils of Sorghum sudanense compared with the control. Significant decrease in the available Cu content was also observed in the rhizosphere soils of the bacterial-inoculated Sorghum sudanense. The results suggest that the endophytic bacterial strain K3-2 may be exploited for promoting Sorghum sudanense biomass production and Cu phytostabilization in the Cu mining wasteland soils.

  2. Subsurface Analysis of the Mesaverde Group on and near the Jicarilla Apache Indian Reservation, New Mexico-its implication on Sites of Oil and Gas Accumulation

    SciTech Connect

    Ridgley, Jennie

    2001-08-21

    The purpose of the phase 2 Mesaverde study part of the Department of Energy funded project ''Analysis of oil-bearing Cretaceous Sandstone Hydrocarbon Reservoirs, exclusive of the Dakota Sandstone, on the Jicarilla Apache Indian Reservation, New Mexico'' was to define the facies of the oil-producing units within the subsurface units of the Mesaverde Group and integrate these results with outcrop studies that defined the depositional environments of these facies within a sequence stratigraphic context. The focus of this report will center on (1) integration of subsurface correlations with outcrop correlations of components of the Mesaverde, (2) application of the sequence stratigraphic model determined in the phase one study to these correlations, (3) determination of the facies distribution of the Mesaverde Group and their relationship to sites of oil and gas accumulation, (4) evaluation of the thermal maturity and potential source rocks for oil and gas in the Mesaverde Group, and (5) evaluation of the structural features on the Reservation as they may control sites of oil accumulation.

  3. Stability of children's insurance coverage and implications for access to care: evidence from the Survey of Income and Program Participation.

    PubMed

    Buchmueller, Thomas; Orzol, Sean M; Shore-Sheppard, Lara

    2014-06-01

    Even as the number of children with health insurance has increased, coverage transitions--movement into and out of coverage and between public and private insurance--have become more common. Using data from 1996 to 2005, we examine whether insurance instability has implications for access to primary care. Because unobserved factors related to parental behavior and child health may affect both the stability of coverage and utilization, we estimate the relationship between insurance and the probability that a child has at least one physician visit per year using a model that includes child fixed effects to account for unobserved heterogeneity. Although we find that unobserved heterogeneity is an important factor influencing cross-sectional correlations, conditioning on child fixed effects we find a statistically and economically significant relationship between insurance coverage stability and access to care. Children who have part-year public or private insurance are more likely to have at least one doctor's visit than children who are uninsured for a full year, but less likely than children with full-year coverage. We find comparable effects for public and private insurance. Although cross-sectional analyses suggest that transitions directly between public and private insurance are associated with lower rates of utilization, the evidence of such an effect is much weaker when we condition on child fixed effects.

  4. Concise Review: When Colonies Are Not Clones: Evidence and Implications of Intracolony Heterogeneity in Mesenchymal Stem Cells.

    PubMed

    Rennerfeldt, Deena A; Van Vliet, Krystyn J

    2016-05-01

    The emergence of heterogeneity in putative mesenchymal stem cell (MSC) populations during in vitro expansion is not appreciated fully by the various communities who study, engineer, and use such stem cells. However, this functional diversity holds direct implications for basic research and therapeutic applications of MSCs that require predictable phenotypic function and efficacy. Despite numerous clinical trials pursuing MSC therapies, the in vitro expansion of homogeneous populations to therapeutically relevant quantities remains an elusive goal. Variation in MSC cultures has been noted not only among donors and within populations expanded from the same donor, but also debatably within single-cell-derived colonies. The potential for even intracolony heterogeneity suggests that any purified subpopulation will inevitably become heterogeneous upon further expansion under current culture conditions. Here, we review the noted or retrospective evidence of intracolony MSC heterogeneity, to facilitate discussion of its possible causes and potential solutions to its mitigation. This analysis suggests that functional diversity within an MSC colony must be considered in design of experiments and trials for even nonclonal stem cell populations, and can be mitigated or even exploited when the mechanisms of onset are better understood. Stem Cells 2016;34:1135-1141.

  5. A Review of the Evidence that Ochratoxin A Is an Nrf2 Inhibitor: Implications for Nephrotoxicity and Renal Carcinogenicity

    PubMed Central

    Limonciel, Alice; Jennings, Paul

    2014-01-01

    Several studies have demonstrated that ochratoxin A (OTA) inhibits the nuclear factor, erythroid 2-like 2 (Nrf2) oxidative stress response pathway. At the cellular level this would attenuate (i) glutathione synthesis; (ii) recycling of oxidised glutathione; (iii) activity of oxidoreductases; and (iv) phase II metabolism inducibility. The effects combined would render the cell and tissue more vulnerable to oxidative stress. Indeed, Nrf2 knock out animals exhibit increased susceptibility to various types of chemical-induced injury. Several studies have shown that OTA exposure can inhibit Nrf2 responses. Such an action would initially lead to increased susceptibility to both physiological and chemical-induced cell stress. However, chronic exposure to OTA may also act as a selective pressure for somatic mutations in Nrf2 or its inhibitor Keap-1, leading to constitutive Nrf2 activation. Nrf2 overexpression confers a survival advantage and is often associated with cancer cell survival. Here we review the evidence for OTA’s role as an Nrf2 inhibitor and discuss the implications of this mechanism in nephrotoxicity and carcinogenicity. PMID:24448208

  6. Periodontal Systemic Connections-Novel Associations-A Review of the Evidence with Implications for Medical Practitioners.

    PubMed

    Kalakonda, Butchibabu; Koppolu, Pradeep; Baroudi, Kusai; Mishra, Ashank

    2016-04-01

    Periodontal diseases, considered as inflammatory diseases have proved to have a spectrum of systemic implications. Earliest research has associated periodontal disease with common systemic aliments such as hypertension, diabetes, osteoporosis, rheumatoid arthritis to name a few. The evolution of advanced diagnostic aids let researchers make vast inroads in linking periodontal diseases to systemic diseases like Alzheimer's disease (AD) and even Schizophrenia. Our aim was to review and critically evaluate comprehensive literature and provide knowledge to medical practitioners on these associations so as to pave way for closer interactions between medical and dental practitioners in implementing better health care. Electronic databases such as PubMed, Google Scholar and Cochrane databases were used as source of the data for relevant studies published from 2005 up to 2015 with the following keywords, "'Periodontal disease", "systemic conditions", "periodontal disease and Alzheimer's", "Periodontal disease and Schizophrenia", "Periodontal disease and Psoriasis" and "Periodontal disease and erectile dysfunction". The evidence presented ascertains that a reasonable and modest association does exist between Periodontal disease and Alzheimer's, Schizophrenia, Erectile dysfunction, as well as Psoriasis and thus establishes periodontal disease as a potential risk factor. PMID:27103910

  7. Mercury accumulation in sediment cores from three Washington state lakes: evidence for local deposition from a coal-fired power plant.

    PubMed

    Furl, Chad V; Meredith, Callie A

    2011-01-01

    Mercury accumulation rates measured in age-dated sediment cores were compared at three Washington state lakes. Offutt Lake and Lake St. Clair are located immediately downwind (18 and 28 km, respectively) of a coal-fired power plant and Lake Sammamish is located outside of the immediate area of the plant (110 km). The sites immediately downwind of the power plant were expected to receive increased mercury deposition from particulate and reactive mercury not deposited at Lake Sammamish. Mercury accumulation in cores was corrected for variable sedimentation, background, and sediment focusing to estimate the anthropogenic contribution (Hg(A,F)). Results indicated lakes immediately downwind of the power plant contained elevated Hg(A,F) levels with respect to the reference lake. Estimated fluxes to Lake Sammamish were compared to measured values from a nearby mercury wet deposition collector to gauge the efficacy of the core deconstruction techniques. Total deposition calculated through the sediment core (20.7 μg/m²/year) fell just outside of the upper estimate (18.9 μg/m²/year) of total deposition approximated from the wet deposition collector. PMID:20437040

  8. Evidence of various mechanisms of Cd sequestration in the hyperaccumulator Arabidopsis halleri, the non-accumulator Arabidopsis lyrata, and their progenies by combined synchrotron-based techniques.

    PubMed

    Isaure, Marie-Pierre; Huguet, Stéphanie; Meyer, Claire-Lise; Castillo-Michel, Hiram; Testemale, Denis; Vantelon, Delphine; Saumitou-Laprade, Pierre; Verbruggen, Nathalie; Sarret, Géraldine

    2015-06-01

    Arabidopsis halleri is a model plant for Zn and Cd hyperaccumulation. The objective of this study was to determine the relationship between the chemical forms of Cd, its distribution in leaves, and Cd accumulation and tolerance. An interspecific cross was carried out between A. halleri and the non-tolerant and non-hyperaccumulating relative A. lyrata providing progenies segregating for Cd tolerance and accumulation. Cd speciation and distribution were investigated using X-ray absorption spectroscopy and microfocused X-ray fluorescence. In A. lyrata and non-tolerant progenies, Cd was coordinated by S atoms only or with a small contribution of O groups. Interestingly, the proportion of O ligands increased in A. halleri and tolerant progenies, and they were predominant in most of them, while S ligands were still present. Therefore, the binding of Cd with O ligands was associated with Cd tolerance. In A. halleri, Cd was mainly located in the xylem, phloem, and mesophyll tissue, suggesting a reallocation process for Cd within the plant. The distribution of the metal at the cell level was further discussed. In A. lyrata, the vascular bundles were also Cd enriched, but the epidermis was richer in Cd as compared with the mesophyll. Cd was identified in trichomes of both species. This work demonstrated that both Cd speciation and localization were related to the tolerance character of the plant. PMID:25873676

  9. Neurochemical evidence that the metabolites accumulating in 3-methylcrotonyl-CoA carboxylase deficiency induce oxidative damage in cerebral cortex of young rats.

    PubMed

    Zanatta, Ângela; Moura, Alana Pimentel; Tonin, Anelise Miotti; Knebel, Lisiane Aurélio; Grings, Mateus; Lobato, Vannessa Araújo; Ribeiro, César Augusto João; Dutra-Filho, Carlos Severo; Leipnitz, Guilhian; Wajner, Moacir

    2013-01-01

    Isolated 3-methylcrotonyl-CoA carboxylase deficiency (3MCCD) is an autosomal recessive disorder of leucine metabolism biochemically characterized by accumulation of 3-methylcrotonylglycine (3MCG), 3-methylcrotonic acid (3MCA) and 3-hydroxyisovaleric acid. A considerable number of affected individuals present neurological symptoms with or without precedent crises of metabolic decompensation and brain abnormalities whose pathogenesis is poorly known. We investigated the in vitro effects of 3MCG and 3MCA on important parameters of oxidative stress in cerebral cortex of young rats. 3MCG and 3MCA significantly increased TBA-RS and carbonyl formation, indicating that these compounds provoke lipid and protein oxidation, respectively. In contrast, nitric oxide production was not affected by 3MCG and 3MCA. Furthermore, 3MCG- and 3MCA-induced elevation of TBA-RS values was fully prevented by melatonin, trolox and reduced glutathione, but not by the nitric oxide inhibitor N(ω)-nitro-L-arginine methyl ester or the combination of catalase plus superoxide dismutase, indicating that reactive oxygen species were involved in the oxidative damage caused by these compounds. We also found that the activity of the antioxidant enzymes glutathione peroxidase, catalase, superoxide dismutase and glutathione reductase were not altered in vitro by 3MCG and 3MCA. It is therefore presumed that alterations of the cellular redox homeostasis caused by the major metabolites accumulating in 3MCCD may potentially be involved in the pathophysiology of the neurological dysfunction and structural brain alterations found in patients affected by this disorder.

  10. Ratjadone C-mediated nuclear accumulation of HDAC4: implications on Runx2-induced osteoblast differentiation of C3H10T1/2 mesenchymal stem cells.

    PubMed

    Mu, Ping; Deepak, Vishwa; Kang, Liheng; Jiang, Qing; Liu, Rong; Meng, Lingyi; Zhang, Zhongli; Zeng, Xianlu; Liu, Wenguang

    2014-01-01

    Histone deacetylases (HDACs) are a group of enzymes that deacetylate ε-N-acetyl lysine residues of histone and non-histone proteins and play an important role in gene regulation. HDAC4, a class-IIa HDAC, has been reported to shuttle between nucleus and cytoplasm in response to various cellular stimuli. The nucleo-cytoplasmic shuttling of HDAC4 is critical, and an anomalous nuclear localization might affect the cellular differentiation program. While the subcellular localization of HDAC4 has been reported to be vital for myoblast differentiation and chondrocyte hypertrophy, nuclear accumulation of HDAC4 during Runx2-induced osteoblast differentiation of stem cells has not been characterized. Ratjadone C is a natural compound that inhibits the nuclear export of proteins. Here, we show that Runx2 is a more potent transcription factor than Osterix in inducing osteoblast differentiation. Under the influence of ratjadone C, HDAC4 is retained in the nucleus and co-localizes with Runx2. However, forced nuclear accumulation of HDAC4 by ratjadone C or overexpression of the nuclear resident form of HDAC4 does not inhibit osteoblast differentiation, suggesting that the Runx2- induced osteogenic program of C3H10T1/2 cells is not affected by HDAC4. Even though phosphorylation of HDAC4 affects its compartmentalization and the stemness of progenitor cells, we found that total HDAC4 and phosphorylated HDAC4 remain cytoplasmic under both osteogenic and nonosteogenic conditions. Collectively, this work demonstrates that, regardless of the nucleo-cytoplasmic presence of HDAC4, the Runx2-induced osteoblast differentiation program of C3H10T1/2 cells remains unaffected. Additionally, the ratjadone C-mediated nuclear retention assay can potentially be used as a screening tool to identify novel regulatory mechanisms of HDAC4 and its functional partners in various pathophysiological conditions.

  11. Knocking Out ACR2 Does Not Affect Arsenic Redox Status in Arabidopsis thaliana: Implications for As Detoxification and Accumulation in Plants

    PubMed Central

    Liu, Wenju; Schat, Henk; Bliek, Mathijs; Chen, Yi; McGrath, Steve P.; George, Graham; Salt, David E.; Zhao, Fang-Jie

    2012-01-01

    Many plant species are able to reduce arsenate to arsenite efficiently, which is an important step allowing detoxification of As through either efflux of arsenite or complexation with thiol compounds. It has been suggested that this reduction is catalyzed by ACR2, a plant homologue of the yeast arsenate reductase ScACR2. Silencing of AtACR2 was reported to result in As hyperaccumulation in the shoots of Arabidopsis thaliana. However, no information of the in vivo As speciation has been reported. Here, we investigated the effect of AtACR2 knockout or overexpression on As speciation, arsenite efflux from roots and As accumulation in shoots. T-DNA insertion lines, overexpression lines and wild-type (WT) plants were exposed to different concentrations of arsenate for different periods, and As speciation in plants and arsenite efflux were determined using HPLC-ICP-MS. There were no significant differences in As speciation between different lines, with arsenite accounting for >90% of the total extractable As in both roots and shoots. Arsenite efflux to the external medium represented on average 77% of the arsenate taken up during 6 h exposure, but there were no significant differences between WT and mutants or overexpression lines. Accumulation of As in the shoots was also unaffected by AtACR2 knockout or overexpression. Additionally, after exposure to arsenate, the yeast (Saccharomyces cerevisiae) strain with ScACR2 deleted showed similar As speciation as the WT with arsenite-thiol complexes being the predominant species. Our results suggest the existence of multiple pathways of arsenate reduction in plants and yeast. PMID:22879969

  12. Direct evidence of "damage accumulation" in cement mantles surrounding femoral hip stems retrieved at autopsy: cement damage correlates with duration of use and BMI.

    PubMed

    Race, A; Miller, M A; Izant, T H; Mann, K A

    2011-09-01

    The "damage accumulation" phenomenon has not been quantitatively demonstrated in clinical cement mantles surrounding femoral hip stems. We stained transverse sections of 11 postmortem retrieved femoral hip components fixed with cement using fluorescent dye-penetrant and quantified cement damage, voids, and cement-bone interface gaps in epifluorescence and white light micrographs. Crack density (Cr.Dn), crack length-density (Cr.Ln.Dn), porosity, and cement-bone interface gap fraction (c/b-gap%) were calculated, normalized by mantle area. Multiple regression tests showed that cement damage (Cr.Ln.Dn. & Cr.Dn.) was significantly positively correlated (r(2)=0.98, p<0.001) with "duration of use" and body mass index ("BMI") but not cement mantle "porosity". There were significant interactions: "duration of use"*"BMI" was strongly predictive (p<0.005) of Cr.Dn.; and "duration of use"*"porosity" was predictive (p=0.04) of Cr.Ln.Dn. Stem related cracks accounted for approximately one fifth of Cr.Dn and one third of Cr.Ln.Dn. The mean c/b-gap% was 13.8% but it did not correlate (r(2)=0.01, p=0.8) with duration of use. We concluded that duration-dependent fatigue damage accumulation occurred during in vivo use. BMI strongly influenced cement crack length and the rate of new crack formation over time. Voids did not increase the rate of crack initiation but appeared to have promoted crack growth over time. Although not progressive, substantial bone resorption at the cement-bone interface appeared to be common.

  13. Influence of soil properties on trace element availability and plant accumulation in a Mediterranean salt marsh polluted by mining wastes: implications for phytomanagement.

    PubMed

    Conesa, H M; María-Cervantes, A; Alvarez-Rogel, J; González-Alcaraz, M N

    2011-09-15

    The aims of this study were to determine the factors which control metal and As phytoavailability in the different microenvironments (Sand Dunes, Salt Flat, Dry River and Shrubs) present at a Mediterranean salt marsh polluted by mining wastes. We performed a field study following a plot sampling survey. The analyses of soil parameters (pH, electrical conductivity (EC), organic carbon contents, etc.), total metal and As concentrations and their phytoavailability assessed with EDTA were related to each microenvironment and the corresponding plant species uptake. The averages of pH and EC were slightly alkaline (pH ≈ 7.5) and saline (≈ 2.2 to 17.1 dS m(-1)) respectively. The soil samples from the Salt Flat subzone showed the highest metal concentrations (e.g. 51 mg kg(-1) Cd, 11,600 mg kg(-1) Pb) while for As, the highest concentrations occurred in the Dry River (380 mg kg(-1) As). The total metal and EDTA-extractable concentrations occurred as it follows: Salt Flat>Dry River>Degraded Dunes>Shrubs. In relation to plant metal and As accumulation, the highest root concentrations were obtained in the species from the Salt Flat subzone: ~17 mg kg(-1) As, ~620 mg kg(-1) Pb, for both, Juncus maritimus and Arthrocnemum macrostachyum. However the highest metal and As shoot concentrations occurred in species from the Sand Dunes: ~23 mg kg(-1) As ~270 mg kg(-1) Pb for Dittrichia viscosa; ~23 mg kg(-1) As, ~390 mg kg(-1) Zn for Crucianella maritima. The occurrence of edaphic gradients including salinity and texture determined the vegetation distribution. However, it cannot be concluded that there was a disturbance due to metal(loid)s soil concentrations in terms of vegetation composition except in the Degraded Dunes and Dry River. The higher EDTA-extractable concentrations were coincidental with the most saline soils but this did not result in higher metal(loid)s plant accumulation.

  14. Effect of major cations (Ca2+, Mg2+, Na+, K+) and anions (SO4(2-), Cl- , NO3-) on Ni accumulation and toxicity in aquatic plant (Lemna minor L.): implications For Ni risk assessment.

    PubMed

    Gopalapillai, Yamini; Hale, Beverley; Vigneault, Bernard

    2013-04-01

    The effect of major cation activity (Ca(2+) , Mg(2+) , Na(+) , K(+) ) on Ni toxicity, with dose expressed as exposure (total dissolved Ni concentration NiTot ) or free Ni ion activity (in solution Ni(2+) ), or as tissue residue (Ni concentration in plant tissue NiTiss ) to the aquatic plant Lemna minor L. was examined. In addition, Ni accumulation kinetics was explored to provide mechanistic insight into current approaches of toxicity modeling, such as the tissue residue approach and the biotic ligand model (BLM), and the implications for plant Ni risk assessment. Major cations did not inhibit Ni accumulation via competitive inhibition as expected by the BLM framework. For example, Ca(2+) and Mg(2+) (sulfate as counter-anion) had an anticompetitive effect on Ni accumulation, suggesting that Ca or Mg forms a ternary complex with Ni-biotic ligand. The counter-anion of the added Ca (sulfate, chloride, or nitrate) affected plant response (percentage of root growth inhibition) to Ni. Generally, sulfate and chloride influenced plant response while nitrate did not, even when compared within the same range of Ca(2+) , which suggests that the anion dominated the observed plant response. Overall, although an effect of major cations on Ni toxicity to L. minor L. was observed at a physiological level, Ni(2+) or NiTot alone modeled plant response, generally within a span of twofold, over a wide range of water chemistry. Thus, consideration of major cation competition for improving Ni toxicity predictions in risk assessment for aquatic plants may not be necessary.

  15. Killing of VRE Enterococcus faecalis by commensal strains: Evidence for evolution and accumulation of mobile elements in the absence of competition.

    PubMed

    Gaca, Anthony O; Gilmore, Michael S

    2016-01-01

    Enterococci are members of the gastrointestinal tract of humans and most animals that, over the past 3 decades, have emerged as leading causes of multidrug resistant hospital acquired infection (HAI). In addition to their general hardiness, many traits have entered enterococcal lineages through horizontal gene transfer, which has led to the evolution of pathogenic hospital-associated lineages uniquely adapted for survival and proliferation in the antibiotic perturbed ecology of the gastrointestinal tract. We recently observed that the accretion of mobile genetic elements in the prototype vancomycin resistant E. faecalis, clinical isolate V583, renders it unable to co-exist with native enterococci in healthy human fecal flora. In this addendum, we discuss how these findings inform our understanding of how multidrug resistant enterococci evolve, and the implications for the development of treatments that limit colonization and spread of highly antibiotic refractory microbes of this type. PMID:26939857

  16. Accumulation of heptaprenyl diphosphate sensitizes Bacillus subtilis to bacitracin: Implications for the mechanism of resistance mediated by the BceAB transporter

    PubMed Central

    Kingston, Anthony W.; Zhao, Heng; Cook, Gregory M.; Helmann, John D.

    2014-01-01

    Heptaprenyl diphosphate (C35-PP) is an isoprenoid intermediate in the synthesis of both menaquinone and the sesquarterpenoids. We demonstrate that inactivation of ytpB, encoding a C35-PP utilizing enzyme required for sesquarterpenoid synthesis, leads to an increased sensitivity to bacitracin, an antibiotic that binds undecaprenyl pyrophosphate (C55-PP), a key intermediate in cell wall synthesis. Genetic studies indicate that bacitracin sensitivity is due to accumulation of C35-PP, rather than the absence of sesquarterpenoids. Sensitivity is accentuated in a ytpB menA double mutant, lacking both known C35-PP consuming enzymes, and in a ytpB strain overexpressing the HepST enzyme that synthesizes C35-PP. Conversely, sensitivity in the ytpB background is suppressed by mutation of hepST or by supplementation with 1,4-dihydroxy-2-naphthoate, a co-substrate with C35-PP for MenA. Bacitracin sensitivity results from impairment of the BceAB and BcrC resistance mechanisms by C35-PP: in a bceAB bcrC double mutant disruption of ytpB no longer increases bacitracin sensitivity. These results suggest that C35-PP inhibits both BcrC (a C55-PP phosphatase) and BceAB (an ABC transporter that confers bacitracin resistance). These findings lead to a model in which BceAB protects against bacitracin by transfer of the target, C55-PP, rather than the antibiotic across the membrane. PMID:24806199

  17. Physical characterization, magnetic measurements, REE geochemistry and biomonitoring of dust load accumulated during a protracted winter fog period and their implications.

    PubMed

    Chakarvorty, Munmun; Pati, Jayanta Kumar; Patil, Shiva Kumar; Shukla, Swati; Niyogi, Ambalika; Saraf, Arun Kumar

    2014-05-01

    The winter fog in India is a recurrent phenomenon for more than a decade now affecting the entire Himalayan and sub-Himalayan regions covering an area of nearly 500,000 km(2). Every winter (December-January), the air and surface transports in cities of northern India (Amritsar, New Delhi, Agra, Gwalior, Kanpur, Lucknow, and Allahabad) are severely disrupted with visibility reduced to <50 m at times. Since dust particles are known to act as nuclei for the fog formation, this study is aimed to carry out physicochemical characterization of the dust particulates accumulated during a protracted fog period from one of the severely fog affected cities of north India (Allahabad; 25°27'33.40″N-81°52'45.47″E). The dust-loaded tree leaves belonging to Ficus bengalensis and Ficus religiosa from 50 different locations between January 24 and 31, 2010 are sampled and characterized. The mass of dust, color, grain shape, size, phase constituents, and mineral magnetic parameters, such as magnetic susceptibility, SIRM, χ fd%, and S-ratio, show minor variation and the regional influence outweighs local anthropogenic contributions. The dust compositions show fractionated rare earth element pattern with a pronounced negative Eu anomaly similar to upper continental crust and further suggesting their derivation from sources located in parts of north and central India.

  18. Sex differences in the accumulation of chlorinated dioxins in the cormorant (Phalacrocorax carbo): implication of hepatic sequestration in the maternal transfer.

    PubMed

    Kubota, Akira; Yoneda, Kumiko; Tanabe, Shinsuke; Iwata, Hisato

    2013-07-01

    This study focuses on gender-specific accumulation features of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/DFs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in common (great) cormorants (Phalacrocorax carbo) collected from Lake Biwa, Japan. Male cormorants showed a tendency to have higher levels of PCDD/DFs and DL-PCBs than did females. For PCDDs, the male-to-female concentration ratio (M/F ratio) for each congener significantly decreased with the liver-to-muscle concentration ratio (Li/Mu ratio). For PCDFs, there also was a weak negative relationship between Li/Mu ratio and M/F ratio. In contrast, for DL-PCBs, M/F ratios showed no correlation with Li/Mu ratios, but increased with an increase in lipophilicity. These results, together with observations from prior studies, suggest that congener-specific hepatic sequestration may be a factor limiting the maternal transfer of PCDDs and, to a lesser extent, PCDFs. Maternal transfer of DL-PCBs seems to favor more lipophilic congeners in the cormorants. PMID:23597727

  19. Fluids in the Palaeogene Formation of Gaoyou Sag in the Southern Part of North Jiangsu Basin, China: Evidence for Hydrocarbon Migration and Accumulation

    NASA Astrophysics Data System (ADS)

    LI, M.; Lou, Z.; Zhu, R.; Jin, A.

    2013-12-01

    Gaoyou Sag, lying in the middle of the Dongtai Depression in the North Jiangsu basin, China, has a well developed fault system and is characterised by structurally complicated oil and gas fields. Its oil-water relationship is very complicated. In the present study, we present the distribution of formation water chemistry, crude oil density, formation pressures and fluid potential in the Palaeogene formation of the Gaoyou Sag . The purpose of this article is to: (1) analyse the cause of hydrochemical diversity; (2) identify the flow pattern and evolution; and (3) understand the interplay between the flow of formation water and hydrocarbon migration and accumulation. The results showed that large variances in formation water chemistry occur in different oilfields of the Gaoyou Sag (Figure 1) due to dilution by meteoric water recharge, concentration by membrane filtration and complexity of geological structure. The low salinity (mean values from 8.53 g/L to 9.67 g/L) of the formation water and heavy crude oil density (up to 0.94g/cm3) in the Xuchuang oilfield indicate influence from meteoric water infiltration; the deep depression areas are mainly of connate origin. Geofluids in the Xuchuang, Zhenwu and Yang'an oilfields mainly flow vertically through the Zhenwu and Hanliu faults, while geofluids in the Shanian oilfield mainly migrate laterally through the reservoirs and are adjusted vertically along some cutting faults. Palaeo-hydrodynamic evolution had an affinity with the generation, migration, accumulation and preservation of hydrocarbons. In the depositional stages of the Dainan and Sanduo formations, formation water was expelled outward and upward from lacustrine mudstones of the deep depression into shallow sands of nearby oilfields, driven by compaction and overpressure. Hydrocarbon migrated with formation water and gathered in appropriate traps, forming primary reservoirs. During the Zhenwu and Sanduo movements, there were tectonic uplifts and the strata

  20. Considering Shame and Its Implications for Student Learning

    ERIC Educational Resources Information Center

    Johnson, Diane Elizabeth

    2012-01-01

    Research evidence is accumulating to suggest that shame can be implicated in important ways in student adjustment to the learning environment. Student survey data spring-fall 2010 suggest that shame is associated with variables thought to be closely related to student learning--sense of community, burnout and achievement goals--and underline the…

  1. Width of late Quaternary deformation of the Enriquillo-Plantain Garden strike-slip fault zone in Haiti and the Jamaica Passage and implications for accumulated stress

    NASA Astrophysics Data System (ADS)

    Mann, P.; Bachhuber, J. L.

    2010-12-01

    The devastating Haiti earthquake of January 12, 2010, is now known to have occurred on multiple rupture planes with most of the seismic energy release along a north-dipping thrust fault located from 0.5 to 15 km north of the main late Quaternary trace of the EPGFZ. Two alternative views of this rupture are that this north-dipping thrust is unrelated to the main trace of the fault - which showed no rupture during the event - or this north-dipping thrust is part of its larger, subsurface “flower zone” of deformation poorly understood because we have no seismic reflection images crossing the EGPFZ in epicentral area of the 2010 earthquake. The significance of distinguishing these two views of fault behavior relates to whether centuries of accumulated stress were not released on the main trace of the EPGFZ (first model) or whether some accumulated stress was released on the low-angle thrust as part of a broad and linked “flower zone” of deformation parallel to the EPGFZ (second model). In this talk we review observations on the width of the EPGFZ deformation to support the latter view that the EPGFZ is in fact a broad zone of deformation commensurate with its tectonic role as a major, active plate boundary fault. Three areas of broad late Quaternary tectonic deformation varying from transpressional to transtensional in structural style are examined using DEM, imagery, surface geologic maps, and aftershock locations. The Cul-de-Sac basin of Haiti is the xx-km-wide, fault bounded alluvial plain upon which the city of Port-au-Prince was constructed in the early 18th century. Merged DEM and geologic map data from the Cul-de-Sac plain show that an en echelon array of large, open folds deforming uplifted and deeply dissected Plio-Pleistocene fans can be traced 3 to 7 km north of the main trace of the EPGFZ. Map studies show that west-northwest-striking, sub-parallel reverse-oblique/strike-slip faults can be mapped transecting the folds at distances of 3 to 5 km north

  2. Three climatic cycles recorded in a loess-palaeosol sequence at Semlac (Romania) - implications for dust accumulation in the Carpathian Basin and the northern Hemisphere

    NASA Astrophysics Data System (ADS)

    Zeeden, Christian; Hambach, Ulrich; Kels, Holger; Schulte, Philipp; Eckmeier, Eileen; Marković, Slobodan; Klasen, Nicole; Lehmkuhl, Frank

    2016-04-01

    Recent investigations of the Semlac loess section in the Southeastern Carpathian Basin, which is situated at the Mureş River in its lower reaches (Banat region, western Romanian), are presented. Dating back to marine isotope stage (MIS) 10, the more than 10 m thick loess sequence includes four fossil sol-complexes developed in homogenous relatively fine silty loess. Because good preservation and sedimentation of fine silt Semlac is regarded as a key section for the Carpathian Basin, which offers possibilities to a) improve the understanding of the type and composition of the lowland loess sequences in the Carpathian Basin also beyond the last interglacial palaeosol complex, b) to reconstruct the temporal evolution of the local loess-palaeosol successions and c) to compare the loess of the region to loess-sequences in adjacent and dust proxy data in the northern hemisphere. A strikingly sinusoidal course of physical property data with depth/time point to relatively homogenous, quasi-continuous background sedimentation of dust, interpreted as long-range transport (LRT). An integrated age model based on correlation to reference records and luminescence dating is compiled. Applying this age model we compare climate proxy data from Semlac to both global data and to data from the very southeast of the Carpathian Basin (Vojvodina, Serbia). The obtained results provide new insight into the dust accumulation regime in the Carpathian Basin and offer new palaeoenvironmental information for the region and are an important step towards establishing a catena from the thin loess-like sediments of the Banat foothills in the East towards the thicker and seemingly more complete loess sections of the southeastern and central Carpathian Basin. Disentangling grain size data from soil formation proxies gives quantitative estimates for the contribution of original sediment and weathering (through soil formation) to the present clay fraction. Patterns of clay from direct sedimentation

  3. Implications of various phosphoenolpyruvate-carbohydrate phosphotransferase system mutations on glycerol utilization and poly(3-hydroxybutyrate) accumulation in Ralstonia eutropha H16

    PubMed Central

    2011-01-01

    The enhanced global biodiesel production is also yielding increased quantities of glycerol as main coproduct. An effective application of glycerol, for example, as low-cost substrate for microbial growth in industrial fermentation processes to specific products will reduce the production costs for biodiesel. Our study focuses on the utilization of glycerol as a cheap carbon source during cultivation of the thermoplastic producing bacterium Ralstonia eutropha H16, and on the investigation of carbohydrate transport proteins involved herein. Seven open reading frames were identified in the genome of strain H16 to encode for putative proteins of the phosphoenolpyruvate-carbohydrate phosphotransferase system (PEP-PTS). Although the core components of PEP-PTS, enzyme I (ptsI) and histidine phosphocarrier protein (ptsH), are available in strain H16, a complete PTS-mediated carbohydrate transport is lacking. Growth experiments employing several PEP-PTS mutants indicate that the putative ptsMHI operon, comprising ptsM (a fructose-specific EIIA component of PTS), ptsH, and ptsI, is responsible for limited cell growth and reduced PHB accumulation (53%, w/w, less PHB than the wild type) of this strain in media containing glycerol as a sole carbon source. Otherwise, the deletion of gene H16_A0384 (ptsN, nitrogen regulatory EIIA component of PTS) seemed to largely compensate the effect of the deleted ptsMHI operon (49%, w/w, PHB). The involvement of the PTS homologous proteins on the utilization of the non-PTS sugar alcohol glycerol and its effect on cell growth as well as PHB and carbon metabolism of R. eutropha will be discussed. PMID:21906371

  4. Strain accumulation and fluid-rock interaction in a naturally deformed diamictite, Willard thrust system, Utah (USA): Implications for crustal rheology and strain softening

    NASA Astrophysics Data System (ADS)

    Yonkee, W. Adolph; Czeck, Dyanna M.; Nachbor, Amelia C.; Barszewski, Christine; Pantone, Spenser; Balgord, Elizabeth A.; Johnson, Kimberly R.

    2013-05-01

    Structural and geochemical patterns of heterogeneously deformed diamictite in northern Utah (USA) record interrelations between strain accumulation, fluid-rock interaction, and softening processes across a major fault (Willard thrust). Different clast types in the diamictite have varying shape fabrics related to competence contrasts with estimated effective viscosity ratios relative to micaceous matrix of: ˜6 and 8 for large quartzite clasts respectively in the Willard hanging wall and footwall; ˜5 and 2 for less altered and more altered granitic clasts respectively in the hanging wall and footwall; and ˜1 for micaceous clasts that approximate matrix strain. Within the footwall, matrix X-Z strain ratios increase from ˜2 to 8 westward along a distinct deformation gradient. Microstructures record widespread mass transfer, alteration of feldspar to mica, and dislocation creep of quartz within matrix and clasts. Fluid influx along microcracks and mesoscopic vein networks increased westward and led to reaction softening and hydrolytic weakening, in conjunction with textural softening from alignment of muscovite aggregates. Consistent Si, Al, and Ti concentrations between matrix, granitic clasts, and protoliths indicate limited volume change. Mg gain and Na loss reflect alteration of feldspar to phengitic muscovite. Within the hanging wall, strain is overall lower with matrix X-Z strain ratios of ˜2 to 4. Microstructures record mass transfer and dislocation creep concentrated in the matrix. Greater Al and Ti concentrations and lower Si concentrations in matrix indicate volume loss by quartz dissolution. Na gain in granitic clasts reflects albitization. Large granitic clasts have less mica alteration and greater competence compared to smaller clasts. Differences in strain and alteration patterns across the Willard thrust fault suggest overall downward (up-temperature) fluid flow in the hanging wall and upward (down-temperature) fluid flow in the footwall.

  5. Agonist-induced production of 1,2-diacylglycerol and phosphatidic acid in intact resistance arteries. Evidence that accumulation of diacylglycerol is not a prerequisite for contraction.

    PubMed

    Ohanian, J; Ollerenshaw, J; Collins, P; Heagerty, A

    1990-05-25

    The production of total amounts of 1,2-diacylglycerol as well as those specifically derived from inositol lipid hydrolysis was studied in intact rat resistance arteries stimulated with either noradrenaline, vasopressin, or angiotensin II at 20 s when the onset of contraction would be nearing its maximum, and at 5 min during the sustained phase of contraction. Total amounts of 1,2-diacylglycerol were not altered by any agonist at 20 s, or at 5 min. However, arachidonate-containing species of 1,2-diacylglycerol were differentially influenced being increased at 5 min by noradrenaline, and decreased at 20 s and 5 min by vasopressin. Only angiotensin II produced substantial increases in this class of 1,2-diacylglycerol at both time points. In order to investigate the fate of this second messenger total and inositol lipid derived phosphatidic acids were then measured at both 20 s and 5 min. Noradrenaline induced a rise in both total and arachidonate-containing phosphatidic acid at both times as did vasopressin. Only small increases were induced by angiotensin II at 20 s. These data demonstrate that the accumulation of 1,2-diacylglycerol generated from inositol lipid breakdown is only observed with activation by angiotensin II. Other agonists produced phosphatidic acids with time and the rate of generation of these lipids is agonist-specific. Thus phosphatidic acid may play a more prominent role during the sustained phase of contraction than previously anticipated.

  6. Argon, oxygen, and boron isotopic evidence documenting 40ArE accumulation in phengite during water-rich high-pressure subduction metasomatism of continental crust

    NASA Astrophysics Data System (ADS)

    Menold, Carrie A.; Grove, Marty; Sievers, Natalie E.; Manning, Craig E.; Yin, An; Young, Edward D.; Ziegler, Karen

    2016-07-01

    were even older, exceeding the time of eclogite formation by a factor of 1.7. In contrast, lower pressure retrograde muscovite present within the host gneiss and in discrete shear zones cutting the selvage yield 40Ar/39Ar ages that were younger than the time of HP metamorphism and consistent with regional cooling age patterns. Our observation of high 40ArE concentrations in phengite from schistose rocks infiltrated by regionally extensive fluids at HP conditions runs contrary to widely held expectations. Conventional wisdom dictates that low phengite/fluid partition coefficients for argon (Dphg/fluid Ar =10-3to10-5) coupled with the dry, closed systems conditions that are widely reported to characterize HP metamorphism of continental crust explains why high concentrations of 40ArE partitions are able to accumulate within phengite. We alternatively propose that phengite/fluid partition coefficients for argon increase linearly with pressure to values as high as 10-2 to allow phengites to accumulate large amounts of 40ArE from aqueous fluids under HP to UHP conditions.

  7. Evidence for early intracellular accumulation of volatile compounds during spadix development in Arum italicum L. and preliminary data on some tropical Aroids

    NASA Astrophysics Data System (ADS)

    Leguet, Aurélia; Gibernau, Marc; Shintu, Laetitia; Caldarelli, Stefano; Moja, Sandrine; Baudino, Sylvie; Caissard, Jean-Claude

    2014-08-01

    Staining and histochemistry of volatile organic compounds (VOCs) were performed at different inflorescence developmental stages on nine aroid species; one temperate, Arum italicum and eight tropical from the genera Caladium, Dieffenbachia and Philodendron. Moreover, a qualitative and quantitative analysis of VOCs constituting the scent of A. italicum, depending on the stage of development of inflorescences was also conducted. In all nine species, vesicles were observed in the conical cells of either the appendix or the stamens (thecae) and the staminodes. VOCs were localised in intracellular vesicles from the early stages of inflorescence development until their release during receptivity of gynoecium. This localisation was observed by the increase of both number and diameter of the vesicles during 1 week before receptivity. Afterwards, vesicles were fewer and smaller but rarely absent. In A. italicum, staining and gas chromatography analyses confirmed that the vesicles contained terpenes. The quantitatively most important ones were the sesquiterpenes, but monoterpenes were not negligible. Indeed, the quantities of terpenes matched the vesicles' size evolution during 1 week. Furthermore, VOCs from different biosynthetic pathways (sesquiterpenes and alkanes) were at their maximum quantity 2 days before gynoecium receptivity (sesquiterpenes and alkanes) or during receptivity (isobutylamine, monoterpenes, skatole and p-cresol). VOCs seemed to be emitted during gynoecium receptivity and/or during thermogenesis, and FADs are accumulated after thermogenesis in the spadix. These complex dynamics of the different VOCs could indicate specialisation of some VOCs and cell machinery to attract pollinators on the one hand and to repulse/protect against phytophagous organisms and pathogens after pollination on the other hand.

  8. Evidence for early intracellular accumulation of volatile compounds during spadix development in Arum italicum L. and preliminary data on some tropical Aroids.

    PubMed

    Leguet, Aurélia; Gibernau, Marc; Shintu, Laetitia; Caldarelli, Stefano; Moja, Sandrine; Baudino, Sylvie; Caissard, Jean-Claude

    2014-08-01

    Staining and histochemistry of volatile organic compounds (VOCs) were performed at different inflorescence developmental stages on nine aroid species; one temperate, Arum italicum and eight tropical from the genera Caladium, Dieffenbachia and Philodendron. Moreover, a qualitative and quantitative analysis of VOCs constituting the scent of A. italicum, depending on the stage of development of inflorescences was also conducted. In all nine species, vesicles were observed in the conical cells of either the appendix or the stamens (thecae) and the staminodes. VOCs were localised in intracellular vesicles from the early stages of inflorescence development until their release during receptivity of gynoecium. This localisation was observed by the increase of both number and diameter of the vesicles during 1 week before receptivity. Afterwards, vesicles were fewer and smaller but rarely absent. In A. italicum, staining and gas chromatography analyses confirmed that the vesicles contained terpenes. The quantitatively most important ones were the sesquiterpenes, but monoterpenes were not negligible. Indeed, the quantities of terpenes matched the vesicles' size evolution during 1 week. Furthermore, VOCs from different biosynthetic pathways (sesquiterpenes and alkanes) were at their maximum quantity 2 days before gynoecium receptivity (sesquiterpenes and alkanes) or during receptivity (isobutylamine, monoterpenes, skatole and p-cresol). VOCs seemed to be emitted during gynoecium receptivity and/or during thermogenesis, and FADs are accumulated after thermogenesis in the spadix. These complex dynamics of the different VOCs could indicate specialisation of some VOCs and cell machinery to attract pollinators on the one hand and to repulse/protect against phytophagous organisms and pathogens after pollination on the other hand. PMID:24925357

  9. A geochemical study of the Riddle Peaks Gabbro, North Cascades: Implications for amphibole accumulation in magmatic differentiation processes in the mid crust of an arc

    NASA Astrophysics Data System (ADS)

    Cota, A. C.; DeBari, S. M.

    2012-12-01

    The Riddle Peaks Pluton (~77 Ma) is an amphibole-rich layered gabbro situated within the Cretaceous and Paleogene North Cascades Crystalline Core (NCCC), emplaced at mid-crustal pressures (6 kbar). This pluton provides an opportunity to constrain the geochemical signature produced during amphibole fractionation in the mid-crust of an ancient arc. Amphibole fractionation is hypothesized to produce a distinctive geochemical signature in arc magmas and continental crust (e.g..high Mg- #s, low Dy/Yb and Nb/Ta ratios). Geochemical characterization of the Riddle Peaks cumulates supports these hypotheses. The Riddle Peaks Gabbro has 40.7-47.2 wt.% SiO2 and Mg-# (100xMg/Mg+Fe) 33-67. These low Mg#s contrast with commonly described primitive pyroxene cumulates, which have Mg# > 85. Fractionation of these low-Mg# amphibole cumulates may be responsible for producing high-Mg residual magmas - which have been noted in the NCCC and average continental crust. Garnet fractionation is commonly thought to produce high-Mg magmas, but crystallization of amphibole cumulates may also generate these magmas. Plots of whole rock chondrite-normalized Rare Earth Element (REE) abundances show patterns consistent with amphibole accumulation, with relative enrichment of moderately heavy REE to either light or heavy REE. REE patterns of cumulate amphibole crystals show similar patterns but have higher abundances. REE concentrations of modeled liquids produced by crystallization of these gabbros closely resemble estimates for average continental crust and arc compositions. REE concentrations in calculated liquids were also compared to compositions from the dominantly tonalitic Cardinal Peak Pluton (72 Ma), which intrudes the Riddle Peaks on its Eastern side, and the tonalitic Ten Peak pluton, chosen to represent an average NCCC pluton. A range of compositions representing mafic and felsic end-members are found in each pluton. Calculated liquids match REE concentrations of the mafic diorites and

  10. Diversity of the ectoines biosynthesis genes in the salt tolerant Streptomyces and evidence for inductive effect of ectoines on their accumulation.

    PubMed

    Sadeghi, Akram; Soltani, Bahram M; Nekouei, Mojtaba Khayam; Jouzani, Gholamreza Salehi; Mirzaei, Hossein Hadavand; Sadeghizadeh, Majid

    2014-01-01

    Streptomyces commonly produce ectoines as compatible solutes to prevent osmotic stresses. Fine structure of the genes producing ectoine (ectC) and hydroxyectoine (ectD) enzymes in Streptomyces rimosus C-2012 as a slightly halophilic bacterium is reported in this study. Deduced amino acid sequences of ectC and ectD genes from strain C-2012 and some other related species were compared and 72-90% and 13-81% identities were detected for ectC and ectD, respectively. High similarity of ectC between closely or distantly related Streptomyces to the strain C-2012 may indicate horizontal transfer of this gene. However, phylogenetic relationships of ectD were correlated with phylogenetic affiliation of the strains. It suggests that the ability of Streptomyces to produce hydroxyectoine has been the result of a vertical transfer event. HPLC analysis showed that strain C-2012 was able to produce ectoine and hydroxyectoine both in the presence and absence of external salinity (up to 0.45 M NaCl). Accordingly, reverse transcription quantitative PCR (RT-qPCR) showed that ectABCD operon in this strain is positively affected by salt. Also, inductive effect of the salt was increased when it was applied with 1 mM of ectoines. Transcription level of ectC was increased 2.7- and 2.9-fold in the medium supplied with salt and ectoine and salt and hydroxyectoine, respectively. The effect of salinity with or without ectoines was more on ectD transcription level than that of ectC. In S. rimosus under salt stress, ectoine and hydroxyectoine biosynthesis primarily depends on the stimulation of ectABCD operon transcription. However, drastic accumulation of ectoine and hydroxyectoine without increase in ectC and ectD transcripts was observed in the medium supplied with salt and ectoines and that suggest there might be additional posttranscriptional level of control. Increases in ratio of some intracellular free amino acids in salt stressed to unstressed conditions were observed in cells grown with

  11. Trace-Element Evidence for an Aqueous Atmospheric Origin of Desert Varnish: implications for the aqueous atmospheric input flux into the ocean

    NASA Astrophysics Data System (ADS)

    Thiagarajan, N.; Lee, C.

    2003-12-01

    Desert varnish is a slow-growing dark patina commonly found on rock surfaces in arid environments. Varnishes consist of about 30% Mn and Fe oxides accompanied by oxides of Si, Al, Mg, K and Ca, which occur primarily in the form of clays. Although it is generally agreed that varnishes have an atmospheric origin, their exact formation mechanism remains highly debated. Two endmember hypotheses are gradual accumulation of wind-blown dust followed by diagenesis, and direct chemical precipitation of dissolved elements from atmospheric aerosols. To rule out one of these hypotheses, we investigated the trace-element systematics of varnishes, in particular, focusing on those elements that have contrasting solubilities in aqueous environments. If our trace element analyses are consistent with the varnishes being derived from dissolved atmospheric constituents then the data can be used to quantify the paleofluxes of the soluble fraction of atmospheric aerosols to various depositional environments. For example, this will have implications for the transport of metals to the ocean that are immediately biologically available. We collected varnishes deposited on smooth basaltic lava flow surfaces in the Cima Volcanic Field (Mojave Desert) and in Death Valley, California. The chosen lava flows retain original flow surface structure and are topographical highs; the effects of erosion are hence minimal. Varnishes were scraped off with a quartz rod to minimize trace element contamination and the trace element compositions were then determined by ICP-MS using an external synthetic standard for calibration. Our analyses show that the rare-earth elements (REEs), Co, Ni, and Pb are enriched 1.5 to 10 times relative to the upper continental crust (UCC) and that Nb, Ti, Ta, Hf, Th, Rb and Cs are depleted to varying degrees relative to UCC and the REEs. These fractionations can be explained by their differing chemical behaviors in aqueous environments. The extreme depletion in Rb and Cs

  12. Evidence of martian perchlorate, chlorate, and nitrate in Mars meteorite EETA79001: Implications for oxidants and organics

    NASA Astrophysics Data System (ADS)

    Kounaves, Samuel P.; Carrier, Brandi L.; O'Neil, Glen D.; Stroble, Shannon T.; Claire, Mark W.

    2014-02-01

    The results from the Viking mission in the mid 1970s provided evidence that the martian surface contained oxidants responsible for destroying organic compounds. In 2008 the Phoenix Wet Chemistry Lab (WCL) found perchlorate (ClO4-) in three soil samples at concentrations from 0.5 to 0.7 wt%. The detection of chloromethane (CH3Cl) and dichloromethane (CH2Cl2) by the Viking pyrolysis gas chromatograph-mass spectrometer (GC-MS) may have been a result of ClO4- at that site oxidizing either terrestrial organic contaminates or, if present, indigenous organics. Recently, the Sample Analysis at Mars (SAM) instrument on the Mars Science Laboratory (MSL) Curiosity directly measured the presence of CH3Cl, CH2Cl2 and, along with measurements of HCl and oxygen, indirectly indicate the presence of ClO4-. However, except for Phoenix, no other direct measurement of the ClO4- anion in martian soil or rock has been made. We report here ion chromatographic (IC) and isotopic analyses of a unique sawdust portion of the martian meteorite EETA79001 that show the presence by mass of 0.6 ± 0.1 ppm ClO4-, 1.4 ± 0.1 ppm ClO3-, and 16 ± 0.2 ppm NO3- at a quantity and location within the meteorite that is difficult to reconcile with terrestrial contamination. The sawdust sample consists of basaltic material with a minor salt-rich inclusion in a mass ratio of ∼300:1, thus the salts may be 300 times more concentrated within the inclusion than the whole sample. The molar ratios of NO3-:ClO4- and Cl:ClO4-, are very different for EETA79001 at ∼40:1 and 15:1, respectively, than the Antarctic soils and ice near where the meteorite was recovered at ∼10,000:1 and 5000:1, respectively. In addition, the isotope ratios for EETA79001 with δ15N = -10.48 ± 0.32‰ and δ18O = +51.61 ± 0.74‰ are significantly different from that of the nearby Miller Range blue ice with δ15N = +102.80 ± 0.14‰ and δ18O = +43.11 ± 0.64‰. This difference is notable, because if the meteorite had been

  13. Internet-Based Self-Help Career Assessments and Interventions: Challenges and Implications for Evidence-Based Career Counseling

    ERIC Educational Resources Information Center

    Gati, Itamar; Asulin-Peretz, Lisa

    2011-01-01

    A major characteristic of the 21st century with significant implications on career decision making is the growing prevalence of Information and Communication Technologies (ICTs). Challenges involving ICT-based self-assessment and self-help interventions aimed at facilitating career decision making are discussed. Specifically, this article focuses…

  14. Martian Chlorine Chemistry: A Study of Perchlorate on the Martian Surface, Evidence of an Ongoing Formation Mechanism and Implications of a Complex Chlorine Cycle

    NASA Astrophysics Data System (ADS)

    Carrier, Brandi L.

    2015-10-01

    The research presented herein addresses the detection of perchlorate on Mars, evidence of perchlorate in Mars meteorite EETA 79001, determination of the perchlorate parent salts at the Phoenix landing site, and the ongoing formation of perchlorate from chloride minerals as well as from other oxychlorine species. The detection of perchlorate in three samples by the Phoenix Wet Chemistry Laboratory and the implication of these results are discussed. The further detection of perchlorate in Mars meteorite EETA 79001 by ion chromatography and the determination of the parent salts of the perchlorate detected at the Phoenix landing site by electrochemical analyses and ion chromatography are detailed and the implications of the identity of the parent salts are discussed. The possible formation pathways for martian perchlorate are then explored and a possible mechanism for ongoing perchlorate formation on the martian surface is detailed. Perchlorate is shown to be formed upon exposure of chloride minerals, as well as of chlorite and chlorate salts, to current Mars relevant conditions including temperature, pressure, ultraviolet radiation and atmospheric composition. The implications of this ongoing perchlorate formation for the survival and detection of organics, the oxidizing nature of the soil, formation of liquid brines and recurring slope lineae are discussed. Further preliminary experiments have been conducted to investigate the effects of perchlorate formation on the survival and degradation of organic compounds.

  15. Partnering to Promote Evidence-Based Practice in a Community Hospital: Implications for Nursing Professional Development Specialists.

    PubMed

    Highfield, Martha E F; Collier, Andrea; Collins, Mara; Crowley, Melanie

    2016-01-01

    Nursing professional development specialists working in community hospitals face significant barriers to evidence-based practice that academic medical centers do not. This article describes 7 years of a multifaceted, service academic partnership in a large, urban, community hospital. The partnership has strengthened the nursing professional development role in promoting evidence-based practice across the scope of practice and serves as a model for others. PMID:27187827

  16. A Comparison of Evidence-Based Practice and the ACRL Information Literacy Standards: Implications for Information Literacy Practice

    ERIC Educational Resources Information Center

    Adams, Nancy E.

    2014-01-01

    Evidence-based practice (EBP), like information literacy, is concerned with an individual's knowledge, skills, and attitudes relating to using information. EBP is now a professional competency in fields as diverse as social work, nursing and allied health fields, and public policy. A comparison of the Association of College and Research Libraries'…

  17. Learning from Experience? Evidence on the Impact and Distribution of Teacher Experience and the Implications for Teacher Policy

    ERIC Educational Resources Information Center

    Rice, Jennifer King

    2013-01-01

    Teacher experience has long been a central pillar of teacher workforce policies in U.S. school systems. The underlying assumption behind many of these policies is that experience promotes effectiveness, but is this really the case? What does existing evidence tell us about how, why, and for whom teacher experience matters? This policy brief…

  18. The Quality of Life Implications of Health Practices among Older Adults: Evidence from the 1991 Canadian General Social Survey.

    ERIC Educational Resources Information Center

    Gillis, Kelly J.; Hirdes, John P.

    1996-01-01

    A survey of permanent residents of Canada over 50 years of age (n=5,102) regarding the effect of smoking, alcohol consumption, obesity, and physical activity found the following: (1) smoking is associated with negative outcomes; (2) there is little evidence of adverse effects for alcohol consumption; (3) physical activity is positive; and (4) body…

  19. TTX accumulation in pufferfish.

    PubMed

    Noguchi, Tamao; Arakawa, Osamu; Takatani, Tomohiro

    2006-03-01

    Tetrodotoxin (TTX) has been detected in a variety of animals. The finding of TTX in the trumpet shell Charonia sauliae strongly suggested that its origin was its food, a TTX-bearing starfish Astropecten polyacanthus. Since then, the food chain has been consistently implicated as the principal means of TTX intoxication. To identify the primary producer of TTX, intestinal bacteria isolated from several TTX-bearers were investigated for their TTX production. The results demonstrated that some of them could produce TTX. Thus the primary TTX producers in the sea are concluded to be marine bacteria. Subsequently, detritus feeders and zooplankton can be intoxicated with TTX through the food chain, or in conjunction with parasitism or symbiosis. The process followed by small carnivores, omnivores or scavengers, and by organisms higher up the food chain would result in the accumulation of higher concentrations of TTX. Finally, pufferfish at the top of the food chain are intoxicated with TTX. This hypothesis is supported by the fact that net cage and land cultures produce non-toxic pufferfish that can be made toxic by feeding with a TTX-containing diet.

  20. GPS estimates of microplate motions, northern Caribbean: evidence for a Hispaniola microplate and implications for earthquake hazard

    NASA Astrophysics Data System (ADS)

    Benford, B.; DeMets, C.; Calais, E.

    2012-09-01

    We use elastic block modelling of 126 GPS site velocities from Jamaica, Hispaniola, Puerto Rico and other islands in the northern Caribbean to test for the existence of a Hispaniola microplate and estimate angular velocities for the Gônave, Hispaniola, Puerto Rico-Virgin Islands and two smaller microplates relative to each other and the Caribbean and North America plates. A model in which the Gônave microplate spans the whole plate boundary between the Cayman spreading centre and Mona Passage west of Puerto Rico is rejected at a high confidence level. The data instead require an independently moving Hispaniola microplate between the Mona Passage and a likely diffuse boundary within or offshore from western Hispaniola. Our updated angular velocities predict 6.8 ± 1.0 mm yr-1 of left-lateral slip along the seismically hazardous Enriquillo-Plantain Garden fault zone of southwest Hispaniola, 9.8 ± 2.0 mm yr-1 of slip along the Septentrional fault of northern Hispaniola and ˜14-15 mm yr-1 of left-lateral slip along the Oriente fault south of Cuba. They also predict 5.7 ± 1 mm yr-1 of fault-normal motion in the vicinity of the Enriquillo-Plantain Garden fault zone, faster than previously estimated and possibly accommodated by folds and faults in the Enriquillo-Plantain Garden fault zone borderlands. Our new and a previous estimate of Gônave-Caribbean plate motion suggest that enough elastic strain accumulates to generate one to two Mw˜ 7 earthquakes per century along the Enriquillo-Plantain Garden and nearby faults of southwest Hispaniola. That the 2010 M= 7.0 Haiti earthquake ended a 240-yr-long period of seismic quiescence in this region raises concerns that it could mark the onset of a new earthquake sequence that will relieve elastic strain that has accumulated since the late 18th century.

  1. A case for modular design: Implications for implementing evidence-based interventions with culturally-diverse youth

    PubMed Central

    Lyon, Aaron R.; Lau, Anna S.; McCauley, Elizabeth; Stoep, Ann Vander; Chorpita, Bruce F.

    2013-01-01

    Community-based therapists are frequently faced with the complex task of applying existing research knowledge to clients who may differ markedly from those enrolled in controlled outcome studies. The current paper examines the utility of modular psychotherapy design as one method of facilitating the flexible delivery of evidence-based mental health services to ethnically and culturally diverse children and families. Modularity complements existing approaches to the provision of culturally-sensitive, empirically-informed treatment through its ability to balance the prioritization of research evidence and local practitioner cultural knowledge. Specific applications of modular principles to clinical work with diverse youth are highlighted. Special considerations and limitations relevant to modular psychotherapy and the overall mental health services research literature are discussed, as well as the continued importance of individual clinicians’ cultural competence and use of treatment progress monitoring, both of which should be combined with identified treatment modules to support the delivery of high-quality care. PMID:25328279

  2. Seismic reflection evidence for a northeast-dipping Hayward fault near Fremont, California: Implications for seismic hazard

    USGS Publications Warehouse

    Williams, R.A.; Simpson, R.W.; Jachens, R.C.; Stephenson, W.J.; Odum, J.K.; Ponce, D.A.

    2005-01-01

    A 1.6-km-long seismic reflection profile across the creeping trace of the southern Hayward fault near Fremont, California, images the fault to a depth of 650 m. Reflector truncations define a fault dip of about 70 degrees east in the 100 to 650 m depth range that projects upward to the creeping surface trace, and is inconsistent with a nearly vertical fault in this vicinity as previously believed. This fault projects to the Mission seismicity trend located at 4-10 km depth about 2 km east of the surface trace and suggests that the southern end of the fault is as seismically active as the part north of San Leandro. The seismic hazard implication is that the Hayward fault may have a more direct connection at depth with the Calaveras fault, affecting estimates of potential event magnitudes that could occur on the combined fault surfaces, thus affecting hazard assessments for the south San Francisco Bay region.

  3. An assessment of maternal, newborn and child health implementation studies in Nigeria: implications for evidence informed policymaking and practice

    PubMed Central

    Uneke, Chigozie Jesse; Sombie, Issiaka; Keita, Namoudou; Lokossou, Virgil; Johnson, Ermel; Ongolo-Zogo, Pierre

    2016-01-01

    Background: The introduction of implementation science into maternal, newborn and child health (MNCH) research has facilitated better methods to improve uptake of research findings into practices. With increase in implementation research related to MNCH world-wide, stronger scientific evidence are now available and have improved MNCH policies in many countries including Nigeria. The purpose of this study was to review MNCH implementation studies undertaken in Nigeria in order to understand the extent the evidence generated informed better policy. Methods: This study was a systematic review. A MEDLINE Entrez PubMed search was performed in August 2015 and implementation studies that investigated MNCH in Nigeria from 1966 to 2015 in relation to health policy were sought. Search key words included Nigeria, health policy, maternal, newborn, and child health. Only policy relevant studies that were implementation or intervention research which generated evidence to improve MNCH in Nigeria were eligible and were selected. Results: A total of 18 relevant studies that fulfilled the study inclusion criteria were identified out of 471 studies found. These studies generated high quality policy relevance evidence relating to task shifting, breastfeeding practices, maternal nutrition, childhood immunization, kangaroo mother care (KMC), prevention of maternal to child transmission of HIV, etc. These indicated significant improvements in maternal health outcomes in localities and health facilities where the studies were undertaken. Conclusion: There is a dire need for more implementation research related to MNCH in low income settings because the priority for improved MNCH outcome is not so much the development of new technologies but solving implementation issues, such as how to scale up and evaluate interventions within complex health systems. PMID:27579255

  4. Phosphorus limitation and starvation effects on cell growth and lipid accumulation in Isochrysis galbana U4 for biodiesel production.

    PubMed

    Roopnarain, A; Gray, V M; Sym, S D

    2014-03-01

    The effect of varying levels of phosphorus (P) on Isochrysis galbana U4 growth, pigmentation and lipid accumulation were investigated. A reduction in the P content to 25% of the recommended level for f/2 medium did not lead to declines in cell growth rates or lipid accumulation levels relative to the cultures maintained on medium supplemented with the normal P dose. Evidence suggesting that the recommended P supply in f/2 exceeds the requirements for maximal algal growth has obvious economic implications for the mass production of I. galbana for biodiesel production. When P supply was in excess this species was also found to accumulate intracellular levels of P that exceeded by up to 6 times its P requirements for growth and cell division. The reduction in P concentration to levels below 25% resulted in P starvation stimulated chlorophyll reductions and carotenoid and lipid accumulation in this species.

  5. Evidence for biological activity in mineralization of secondary sulphate deposits in a basaltic environment: implications for the search for life in the Martian subsurface

    SciTech Connect

    C. Doc Richardson; Nancy W. Hinman; Jill R. Scott

    2013-10-01

    Evidence of microbial activity associated with mineralization of secondary Na-sulphate minerals (thenardite, mirabilite) in the basaltic subsurface of Craters of the Moon National Monument (COM), Idaho were examined by scanning electron microscopy, X-ray diffraction, laser desorption Fourier transform ion cyclotron resonance mass spectrometry (LD-FTICR-MS), Fourier transform infrared spectroscopy (FTIR) and isotope ratio mass spectrometry. Peaks suggestive of bio/organic compounds were observed in the secondary Na-sulphate deposits by LD-FTICR-MS. FTIR provided additional evidence for the presence of bio/organic compounds. Sulphur fractionation was explored to assist in determining if microbes may play a role in oxidizing sulphur. The presence of bio/organic compounds associated with Na-sulphate deposits, along with the necessity of oxidizing reduced sulphur to sulphate, suggests that biological activity may be involved in the formation of these secondary minerals. The secondary Na-sulphate minerals probably form from the overlying basalt through leached sodium ions and sulphate ions produced by bio-oxidation of Fe-sulphide minerals. Since the COM basalts are one of the most comparable terrestrial analogues for their Martian counterparts, the occurrence of biological activity in the formation of sulphate minerals at COM has direct implications for the search for life on Mars. In addition, the presence of caves on Mars suggests the importance of these environments as possible locations for growth and preservation of microbial activity. Therefore, understanding the physiochemical pathways of abiotic and biotic mineralization in the COM subsurface and similar basaltic settings has direct implications for the search for extinct or extant life on Mars.

  6. Evidence of recent climate change within the historic range of Rio Grande cutthroat trout: implications for management and future persistence

    USGS Publications Warehouse

    Zeigler, Matthew P.; Todd, Andrew S.; Caldwell, Colleen A.

    2012-01-01

    Evidence of anthropogenically influenced climate change has motivated natural resource managers to incorporate adaptive measures to minimize risks to sensitive and threatened species. Detecting trends in climate variables (i.e., air temperature and hydrology) can serve as a valuable management tool for protecting vulnerable species by increasing our understanding of localized conditions and trends. The Rio Grande cutthroat trout Oncorhynchus clarkii virginalis has suffered a severe decline in its historical distribution, with the majority of current populations persisting in isolated headwater streams. To evaluate recent climate change within the subspecies' historical range, we examined trends in average air temperatures, biologically important hydrological variables (timing of snowmelt and seasonal flows), and the April 1 snow water equivalent over the last 45 years (1963–2007). While rates of change in all three metrics were variable across sites, rangewide patterns were evident. Across the subspecies' historical range, average annual air temperatures increased (0.29°C per decade) and the timing of snowmelt shifted 10.6 d earlier in the year (2.3 d/decade). Flows increased during biologically important periods, including winter (January 1–March 31; 6.6% increase per decade), prespawning (April 1–May 14; 6.9% increase per decade), and spawning (May 15–June 15; 4.2% increase per decade) and decreased in summer (June 16–September 15; 1.9% decrease per decade). Evidence of decreasing April 1 snow water equivalent (5.3% per decade) was also observed. While the impacts of these changes at the population level are equivocal, it is likely that negative effects would influence the subspecies by altering its distribution, decreasing available habitat, and altering the timing of important life history components. Continued monitoring and proactive management will be required to increase the resiliency of remaining populations to ensure long-term persistence and

  7. Declarative memory and skill-related knowledge: Evidence from a case study of amnesia and implications for theories of memory.

    PubMed

    Gregory, Emma; McCloskey, Michael; Ovans, Zoe; Landau, Barbara

    2016-01-01

    Theoretical and empirical studies of memory have long been framed by a distinction between declarative and non-declarative memory. We question the sharpness of the distinction by reporting evidence from amnesic L.S.J., who despite retrograde memory losses in declarative knowledge domains, shows sparing of declarative knowledge related to premorbid skill (e.g., playing an instrument). We previously showed that L.S.J. had severe losses of retrograde declarative knowledge across areas of premorbid expertise (e.g., artists of famous works) and everyday knowledge (e.g., company names for logos). Here we present evidence that L.S.J. has sparing of what we call skill-related declarative knowledge, in four domains in which she had premorbid skill (art, music, aviation, driving). L.S.J.'s pattern of loss and sparing raises questions about the strict separation between classically-defined memory types and aligns with a recent proposal by Stanley and Krakauer [2013. Motor skill depends on knowledge of facts. Frontiers in Human Neuroscience, 7,1-11].

  8. Evidence for ciliary pigment localization in colored ciliates and implications for their photosensory transduction chain: a confocal microscopy study.

    PubMed

    Colombetti, Giuliano; Checcucci, Giovanni; Lucia, Sabina; Usai, Cesare; Ramoino, Paola; Bianchini, Paolo; Pesce, Mattia; Vicidomini, Giuseppe; Diaspro, Alberto

    2007-12-01

    In this study we report for the first time the localization of a photoreceptor pigment in the cilia of the colored heterotrich ciliates Blepharisma japonicum red and blue form, Fabrea salina, and Stentor coeruleus, as result of a confocal microscopy investigation. Optical sectioning confocal microscopy has been used for studying the spatial distribution of the pigment in the cell body, surprisingly showing that, besides its expected presence in the cortical region immediately below the cell membrane, it is located in the cilia too. In order to ascertain possible differences in the pigment fluorescence properties along the cell body, we have measured emission spectra from different parts of it (anterior, posterior, and cilia). Our results clearly indicate that in all cases the spectra are the same, within experimental errors. Finally, we have evaluated the pigment relative fluorescence efficiency of these ciliates. In an ordered scale from lower to greater efficiency, we have S. coeruleus, B. japonicum blue, B. japonicum red, and F. salina. The possible implications of our findings for the process of photosensory transduction are discussed. PMID:17661390

  9. Isotopic inhomogeneity of leaf water: Evidence and implications for the use of isotopic signals transduced by plants

    NASA Astrophysics Data System (ADS)

    Yakir, Dan; DeNiro, Michael J.; Rundel, Philip W.

    1989-10-01

    Variations as large as 11%. in δ18O values and 50%. in δD values were observed among different fractions of water in leaves of ivy (Hedera helix) and sunflower (Helianthus annuus). This observation contradicts previous experimental approaches to leaf water as an isotopically uniform pool. Using ion analysis of the water fractions to identify sources within the leaf, we conclude that the isotopic composition of the water within cells, which is involved in biosynthesis and therefore recorded in the plant organic matter, differs substantially from that of total leaf water. This conclusion must be taken into account in studies in which isotope ratios of fossil plant cellulose are interpreted in paleoclimatic terms. In addition, our results have implications for attempts to explain the Dole effect and to account for the variations of 18O/16O ratios in atmospheric carbon dioxide, since the isotopic composition of cell water, not of total leaf water, influences theδ18O values of O2 and CO2 released from plants into the atmosphere.

  10. Sexual selection and maintenance of sex: evidence from comparisons of rates of genomic accumulation of mutations and divergence of sex-related genes in sexual and hermaphroditic species of Caenorhabditis.

    PubMed

    Artieri, Carlo G; Haerty, Wilfried; Gupta, Bhagwati P; Singh, Rama S

    2008-05-01

    Several hypotheses have been proposed to explain the persistence of dioecy despite the reproductive advantages conferred to hermaphrodites, including greater efficiency at purging deleterious mutations in the former. Dioecy can benefit from both mutation purging and accelerated evolution by bringing together beneficial mutations in the same individual via recombination and shuffling of genotypes. In addition, mathematical treatment has shown that sexual selection is also capable of mitigating the cost of maintaining separate sexes by increasing the overall fitness of sexual populations, and genomic comparisons have shown that sexual selection can lead to accelerated evolution. Here, we examine the advantages of dioecy versus hermaphroditism by comparing the rate of evolution in sex-related genes and the rate of accumulation of deleterious mutations using a large number of orthologs (11,493) in the dioecious Caenorhabditis remanei and the hermaphroditic Caenorhabditis briggsae. We have used this data set to estimate the deleterious mutation rate per generation, U, in both species and find that although it is significantly higher in hermaphrodites, both species are at least 2 orders of magnitude lower than the value required to explain the persistence of sex by efficiency at purging deleterious mutations alone. We also find that genes expressed in sperm are evolving rapidly in both species; however, they show a greater increase in their rate of evolution relative to genes expressed in other tissues in C. remanei, suggesting stronger sexual selection pressure acting on these genes in dioecious species. Interestingly, the persistence of a signal of rapid evolution of sperm genes in C. briggsae suggests a recent evolutionary origin of hermaphrodism in this lineage. Our results provide empirical evidence of increased sexual selection pressure in dioecious animals, supporting the possibility that sexual selection may play an important role in the maintenance of sexual

  11. A Conspicuous Clay Ovoid in Nakhla: Evidence for Subsurface Hydrothermal Alteration on Mars with Implications for Astrobiology

    PubMed Central

    Haigh, Sarah; Lyon, Ian

    2014-01-01

    Abstract A conspicuous biomorphic ovoid structure has been discovered in the Nakhla martian meteorite, made of nanocrystalline iron-rich saponitic clay and amorphous material. The ovoid is indigenous to Nakhla and occurs within a late-formed amorphous mesostasis region of rhyolitic composition that is interstitial to two clinopyroxene grains with Al-rich rims, and contains acicular apatite crystals, olivine, sulfides, Ti-rich magnetite, and a new mineral of the rhoenite group. To infer the origin of the ovoid, a large set of analytical tools was employed, including scanning electron microscopy and backscattered electron imaging, wavelength-dispersive X-ray analysis, X-ray mapping, Raman spectroscopy, time-of-flight secondary ion mass spectrometry analysis, high-resolution transmission electron microscope imaging, and atomic force microscope topographic mapping. The concentric wall of the ovoid surrounds an originally hollow volume and exhibits internal layering of contrasting nanotextures but uniform chemical composition, and likely inherited its overall shape from a preexisting vesicle in the mesostasis glass. A final fibrous layer of Fe-rich phases blankets the interior surfaces of the ovoid wall structure. There is evidence that the parent rock of Nakhla has undergone a shock event from a nearby bolide impact that melted the rims of pyroxene and the interstitial matter and initiated an igneous hydrothermal system of rapidly cooling fluids, which were progressively mixed with fluids from the melted permafrost. Sharp temperature gradients were responsible for the crystallization of Al-rich clinopyroxene rims, rhoenite, acicular apatites, and the quenching of the mesostasis glass and the vesicle. During the formation of the ovoid structure, episodic fluid infiltration events resulted in the precipitation of saponite rinds around the vesicle walls, altered pyrrhotite to marcasite, and then isolated the ovoid wall structure from the rest of the system by depositing a

  12. A conspicuous clay ovoid in Nakhla: evidence for subsurface hydrothermal alteration on Mars with implications for astrobiology.

    PubMed

    Chatzitheodoridis, Elias; Haigh, Sarah; Lyon, Ian

    2014-08-01

    Abstract A conspicuous biomorphic ovoid structure has been discovered in the Nakhla martian meteorite, made of nanocrystalline iron-rich saponitic clay and amorphous material. The ovoid is indigenous to Nakhla and occurs within a late-formed amorphous mesostasis region of rhyolitic composition that is interstitial to two clinopyroxene grains with Al-rich rims, and contains acicular apatite crystals, olivine, sulfides, Ti-rich magnetite, and a new mineral of the rhoenite group. To infer the origin of the ovoid, a large set of analytical tools was employed, including scanning electron microscopy and backscattered electron imaging, wavelength-dispersive X-ray analysis, X-ray mapping, Raman spectroscopy, time-of-flight secondary ion mass spectrometry analysis, high-resolution transmission electron microscope imaging, and atomic force microscope topographic mapping. The concentric wall of the ovoid surrounds an originally hollow volume and exhibits internal layering of contrasting nanotextures but uniform chemical composition, and likely inherited its overall shape from a preexisting vesicle in the mesostasis glass. A final fibrous layer of Fe-rich phases blankets the interior surfaces of the ovoid wall structure. There is evidence that the parent rock of Nakhla has undergone a shock event from a nearby bolide impact that melted the rims of pyroxene and the interstitial matter and initiated an igneous hydrothermal system of rapidly cooling fluids, which were progressively mixed with fluids from the melted permafrost. Sharp temperature gradients were responsible for the crystallization of Al-rich clinopyroxene rims, rhoenite, acicular apatites, and the quenching of the mesostasis glass and the vesicle. During the formation of the ovoid structure, episodic fluid infiltration events resulted in the precipitation of saponite rinds around the vesicle walls, altered pyrrhotite to marcasite, and then isolated the ovoid wall structure from the rest of the system by depositing a

  13. Evidence for gill slits and a pharynx in Cambrian vetulicolians: implications for the early evolution of deuterostomes

    PubMed Central

    2012-01-01

    Background Vetulicolians are a group of Cambrian metazoans whose distinctive bodyplan continues to present a major phylogenetic challenge. Thus, we see vetulicolians assigned to groups as disparate as deuterostomes and ecdysozoans. This divergence of opinions revolves around a strikingly arthropod-like body, but one that also bears complex lateral structures on its anterior section interpreted as pharyngeal openings. Establishing the homology of these structures is central to resolving where vetulicolians sit in metazoan phylogeny. Results New material from the Chengjiang Lagerstätte helps to resolve this issue. Here, we demonstrate that these controversial structures comprise grooves with a series of openings. The latter are oval in shape and associated with a complex anatomy consistent with control of their opening and closure. Remains of what we interpret to be a musculature, combined with the capacity for the grooves to contract, indicate vetulicolians possessed a pumping mechanism that could process considerable volumes of seawater. Our observations suggest that food captured in the anterior cavity was transported to dorsal and ventral gutters, which then channeled material to the intestine. This arrangement appears to find no counterpart in any known fossil or extant arthropod (or any other ecdysozoan). Anterior lateral perforations, however, are diagnostic of deuterostomes. Conclusions If the evidence is against vetulicolians belonging to one or other group of ecdysozoan, then two phylogenetic options seem to remain. The first is that such features as vetulicolians possess are indicative of either a position among the bilaterians or deuterostomes but apart from the observation that they themselves form a distinctive and recognizable clade current evidence can permit no greater precision as to their phylogenetic placement. We argue that this is too pessimistic a view, and conclude that evidence points towards vetulicolians being members of the stem

  14. A conspicuous clay ovoid in Nakhla: evidence for subsurface hydrothermal alteration on Mars with implications for astrobiology.

    PubMed

    Chatzitheodoridis, Elias; Haigh, Sarah; Lyon, Ian

    2014-08-01

    Abstract A conspicuous biomorphic ovoid structure has been discovered in the Nakhla martian meteorite, made of nanocrystalline iron-rich saponitic clay and amorphous material. The ovoid is indigenous to Nakhla and occurs within a late-formed amorphous mesostasis region of rhyolitic composition that is interstitial to two clinopyroxene grains with Al-rich rims, and contains acicular apatite crystals, olivine, sulfides, Ti-rich magnetite, and a new mineral of the rhoenite group. To infer the origin of the ovoid, a large set of analytical tools was employed, including scanning electron microscopy and backscattered electron imaging, wavelength-dispersive X-ray analysis, X-ray mapping, Raman spectroscopy, time-of-flight secondary ion mass spectrometry analysis, high-resolution transmission electron microscope imaging, and atomic force microscope topographic mapping. The concentric wall of the ovoid surrounds an originally hollow volume and exhibits internal layering of contrasting nanotextures but uniform chemical composition, and likely inherited its overall shape from a preexisting vesicle in the mesostasis glass. A final fibrous layer of Fe-rich phases blankets the interior surfaces of the ovoid wall structure. There is evidence that the parent rock of Nakhla has undergone a shock event from a nearby bolide impact that melted the rims of pyroxene and the interstitial matter and initiated an igneous hydrothermal system of rapidly cooling fluids, which were progressively mixed with fluids from the melted permafrost. Sharp temperature gradients were responsible for the crystallization of Al-rich clinopyroxene rims, rhoenite, acicular apatites, and the quenching of the mesostasis glass and the vesicle. During the formation of the ovoid structure, episodic fluid infiltration events resulted in the precipitation of saponite rinds around the vesicle walls, altered pyrrhotite to marcasite, and then isolated the ovoid wall structure from the rest of the system by depositing a

  15. Evident and latent plasticity across the rice diterpene synthase family with potential implications for the evolution of diterpenoid metabolism in the cereals

    PubMed Central

    Morrone, Dana; Hillwig, Matthew L.; Mead, Matthew E.; Lowry, Luke; Fulton, D. Bruce; Peters, Reuben J.

    2013-01-01

    SYNOPSIS The evolution of natural products biosynthetic pathways can be envisioned to occur via a number of mechanisms. Here we provide evidence that latent plasticity plays a role in such metabolic evolution. In particular, rice (Oryza sativa) produces both ent- and syn-copalyl diphosphate (CPP), which are substrates for downstream diterpene synthases. Here we report that several members of this enzymatic family exhibit dual reactivity with some pairing of ent-, syn-, or normal CPP stereochemistry. Evident plasticity was observed, as a previously reported ent-sandaracopimaradiene synthase also converts syn-CPP to syn-labda-8(17),12E,14-triene, which can be found in planta. Notably, normal CPP is not naturally found in rice. Thus, the presence of diterpene synthases that react with this non-native metabolite reveals latent enzymatic/metabolic plasticity, providing biochemical capacity for utilization of such a novel substrate (i.e., normal CPP) that may arise during evolution, the implications of which are discussed. PMID:21323642

  16. Evident and latent plasticity across the rice diterpene synthase family with potential implications for the evolution of diterpenoid metabolism in the cereals.

    PubMed

    Morrone, Dana; Hillwig, Matthew L; Mead, Matthew E; Lowry, Luke; Fulton, D Bruce; Peters, Reuben J

    2011-05-01

    The evolution of natural product biosynthetic pathways can be envisioned to occur via a number of mechanisms. In the present study we provide evidence that latent plasticity plays a role in such metabolic evolution. In particular, rice (Oryza sativa) produces both ent- and syn-CPP (copalyl diphosphate), which are substrates for downstream diterpene synthases. In the present paper we report that several members of this enzymatic family exhibit dual reactivity with some pairing of ent-, syn- or normal CPP stereochemistry. Evident plasticity was observed, as a previously reported ent-sandaracopimaradiene synthase also converts syn-CPP into syn-labda-8(17),12E,14-triene, which can be found in planta. Notably, normal CPP is not naturally found in rice. Thus the presence of diterpene synthases that react with this non-native metabolite reveals latent enzymatic/metabolic plasticity, providing biochemical capacity for utilization of such a novel substrate (i.e. normal CPP) which may arise during evolution, the implications of which are discussed.

  17. Evidence of two genetic clusters of manatees with low genetic diversity in Mexico and implications for their conservation.

    PubMed

    Nourisson, Coralie; Morales-Vela, Benjamín; Padilla-Saldívar, Janneth; Tucker, Kimberly Pause; Clark, Annmarie; Olivera-Gómez, Leon David; Bonde, Robert; McGuire, Peter

    2011-07-01

    The Antillean manatee (Trichechus manatus manatus) occupies the tropical coastal waters of the Greater Antilles and Caribbean, extending from Mexico along Central and South America to Brazil. Historically, manatees were abundant in Mexico, but hunting during the pre-Columbian period, the Spanish colonization and throughout the history of Mexico, has resulted in the significantly reduced population occupying Mexico today. The genetic structure, using microsatellites, shows the presence of two populations in Mexico: the Gulf of Mexico (GMx) and Chetumal Bay (ChB) on the Caribbean coast, with a zone of admixture in between. Both populations show low genetic diversity (GMx: N(A) = 2.69; H(E) = 0.41 and ChB: N(A) = 3.0; H(E) = 0.46). The lower genetic diversity found in the GMx, the largest manatee population in Mexico, is probably due to a combination of a founder effect, as this is the northern range of the sub-species of T. m. manatus, and a bottleneck event. The greater genetic diversity observed along the Caribbean coast, which also has the smallest estimated number of individuals, is possibly due to manatees that come from the GMx and Belize. There is evidence to support limited or unidirectional gene flow between these two important areas. The analyses presented here also suggest minimal evidence of a handful of individual migrants possibly between Florida and Mexico. To address management issues we suggest considering two distinct genetic populations in Mexico, one along the Caribbean coast and one in the riverine systems connected to the GMx.

  18. Older American Indians’ Perspectives on Health, Arthritis, and Physical Activity: Implications for Adapting Evidence-Based Interventions, Oregon, 2013

    PubMed Central

    Schure, Marc B.; Goins, R. Turner

    2016-01-01

    Introduction Despite the high prevalence of arthritis and physical disability among older American Indians, few evidence-based interventions that improve arthritis self-management via physical activity have been adapted for use in this population. The purpose of this study was to identify beliefs about health, arthritis, and physical activity among older American Indians living in a rural area in Oregon to help select and adapt an arthritis self-management program. Methods In partnership with a tribal health program, we conducted surveys, a focus group, and individual interviews with older American Indians with arthritis. Our sample comprised 6 focus group participants and 18 interviewees. The 24 participants were aged 48 to 82 years, of whom 67% were women. Forms B and C of the Multidimensional Health Locus of Control (MHLC) instrument, modified for arthritis, measured MHLC. Results The concepts of health, arthritis, and physical activity overlapped in that health was a holistic concept informed by cultural teachings that included living a healthy lifestyle, socializing, and being functionally independent. Arthritis inhibited health and healthy behaviors. Participants identified barriers such as unreliable transportation and recruiting challenges that would make existing interventions challenging to implement in this setting. The Doctor subscale had the highest MHLC (mean = 4.4 [standard deviation (SD), 1.0]), followed by the Internal subscale (3.9 [SD, 1.4]) and the Other People subscale (2.8 [SD, 1.1]). Conclusions Existing evidence-based programs for arthritis should be adapted to address implementation factors, such as access to transportation, and incorporate cultural values that emphasize holistic wellness and social interconnectedness. Culturally sensitive programs that build on indigenous values and practices to promote active coping strategies for older American Indians with arthritis are needed. PMID:27337558

  19. Evidence of two genetic clusters of manatees with low genetic diversity in Mexico and implications for their conservation.

    PubMed

    Nourisson, Coralie; Morales-Vela, Benjamín; Padilla-Saldívar, Janneth; Tucker, Kimberly Pause; Clark, Annmarie; Olivera-Gómez, Leon David; Bonde, Robert; McGuire, Peter

    2011-07-01

    The Antillean manatee (Trichechus manatus manatus) occupies the tropical coastal waters of the Greater Antilles and Caribbean, extending from Mexico along Central and South America to Brazil. Historically, manatees were abundant in Mexico, but hunting during the pre-Columbian period, the Spanish colonization and throughout the history of Mexico, has resulted in the significantly reduced population occupying Mexico today. The genetic structure, using microsatellites, shows the presence of two populations in Mexico: the Gulf of Mexico (GMx) and Chetumal Bay (ChB) on the Caribbean coast, with a zone of admixture in between. Both populations show low genetic diversity (GMx: N(A) = 2.69; H(E) = 0.41 and ChB: N(A) = 3.0; H(E) = 0.46). The lower genetic diversity found in the GMx, the largest manatee population in Mexico, is probably due to a combination of a founder effect, as this is the northern range of the sub-species of T. m. manatus, and a bottleneck event. The greater genetic diversity observed along the Caribbean coast, which also has the smallest estimated number of individuals, is possibly due to manatees that come from the GMx and Belize. There is evidence to support limited or unidirectional gene flow between these two important areas. The analyses presented here also suggest minimal evidence of a handful of individual migrants possibly between Florida and Mexico. To address management issues we suggest considering two distinct genetic populations in Mexico, one along the Caribbean coast and one in the riverine systems connected to the GMx. PMID:21681472

  20. Evidence of a Large-Magnitude Recent Prehistoric Earthquake on the Bear River Fault, Wyoming and Utah: Implications for Recurrence

    NASA Astrophysics Data System (ADS)

    Hecker, S.; Schwartz, D. P.

    2015-12-01

    Trenching across the antithetic strand of the Bear River normal fault in Utah has exposed evidence of a very young surface rupture. AMS radiocarbon analysis of three samples comprising pine-cone scales and needles from a 5-cm-thick faulted layer of organic detritus indicates the earthquake occurred post-320 CAL yr. BP (after A.D. 1630). The dated layer is buried beneath topsoil and a 15-cm-high scarp on the forest floor. Prior to this study, the entire surface-rupturing history of this nascent normal fault was thought to consist of two large events in the late Holocene (West, 1994; Schwartz et al., 2012). The discovery of a third, barely pre-historic, event led us to take a fresh look at geomorphically youthful depressions on the floodplain of the Bear River that we had interpreted as possible evidence of liquefaction. The appearance of these features is remarkably similar to sand-blow craters formed in the near-field of the M6.9 1983 Borah Peak earthquake. We have also identified steep scarps (<2 m high) and a still-forming coarse colluvial wedge near the north end of the fault in Wyoming, indicating that the most recent event ruptured most or all of the 40-km length of the fault. Since first rupturing to the surface about 4500 years ago, the Bear River fault has generated large-magnitude earthquakes at intervals of about 2000 years, more frequently than most active faults in the region. The sudden initiation of normal faulting in an area of no prior late Cenozoic extension provides a basis for seismic hazard estimates of the maximum-magnitude background earthquake (earthquake not associated with a known fault) for normal faults in the Intermountain West.

  1. Evidence of two genetic clusters of manatees with low genetic diversity in Mexico and implications for their conservation

    USGS Publications Warehouse

    Nourisson, Coralie; Morales-Vela, Benjamin; Padilla-Saldivar, Janneth; Tucker, Kimberly Pause; Clark, Ann Marie; Olivera-Gomez, Leon David; Bonde, Robert; McGuire, Peter

    2011-01-01

    The Antillean manatee (Trichechus manatus manatus) occupies the tropical coastal waters of the Greater Antilles and Caribbean, extending from Mexico along Central and South America to Brazil. Historically, manatees were abundant in Mexico, but hunting during the pre-Columbian period, the Spanish colonization and throughout the history of Mexico, has resulted in the significantly reduced population occupying Mexico today. The genetic structure, using microsatellites, shows the presence of two populations in Mexico: the Gulf of Mexico (GMx) and Chetumal Bay (ChB) on the Caribbean coast, with a zone of admixture in between. Both populations show low genetic diversity (GMx: NA = 2.69; HE = 0.41 and ChB: NA = 3.0; HE = 0.46). The lower genetic diversity found in the GMx, the largest manatee population in Mexico, is probably due to a combination of a founder effect, as this is the northern range of the sub-species of T. m. manatus, and a bottleneck event. The greater genetic diversity observed along the Caribbean coast, which also has the smallest estimated number of individuals, is possibly due to manatees that come from the GMx and Belize. There is evidence to support limited or unidirectional gene flow between these two important areas. The analyses presented here also suggest minimal evidence of a handful of individual migrants possibly between Florida and Mexico. To address management issues we suggest considering two distinct genetic populations in Mexico, one along the Caribbean coast and one in the riverine systems connected to the GMx.

  2. Evidence of two genetic clusters of manatees with low genetic diversity in Mexico and implications for their conservation

    USGS Publications Warehouse

    Nourisson, C.; Morales-Vela, B.; Padilla-Saldivar, J.; Tucker, K.P.; Clark, A.; Olivera-Gomez, L. D.; Bonde, R.; McGuire, P.

    2011-01-01

    The Antillean manatee (Trichechus manatus manatus) occupies the tropical coastal waters of the Greater Antilles and Caribbean, extending from Mexico along Central and South America to Brazil. Historically, manatees were abundant in Mexico, but hunting during the pre-Columbian period, the Spanish colonization and throughout the history of Mexico, has resulted in the significantly reduced population occupying Mexico today. The genetic structure, using microsatellites, shows the presence of two populations in Mexico: the Gulf of Mexico (GMx) and Chetumal Bay (ChB) on the Caribbean coast, with a zone of admixture in between. Both populations show low genetic diversity (GMx: NA=2.69; HE=0.41 and ChB: NA=3.0; HE=0.46). The lower genetic diversity found in the GMx, the largest manatee population in Mexico, is probably due to a combination of a founder effect, as this is the northern range of the sub-species of T. m. manatus, and a bottleneck event. The greater genetic diversity observed along the Caribbean coast, which also has the smallest estimated number of individuals, is possibly due to manatees that come from the GMx and Belize. There is evidence to support limited or unidirectional gene flow between these two important areas. The analyses presented here also suggest minimal evidence of a handful of individual migrants possibly between Florida and Mexico. To address management issues we suggest considering two distinct genetic populations in Mexico, one along the Caribbean coast and one in the riverine systems connected to the GMx. ?? 2011 Springer Science+Business Media B.V.

  3. Olivine in Martian Meteorite Allan Hills 84001: Evidence for a High-Temperature Origin and Implications for Signs of Life

    NASA Technical Reports Server (NTRS)

    Shearer, C. K.; Leshin, L. A.; Adcock, C. T.

    1999-01-01

    Olivine from Martian meteorite Allan Hills (ALH) 84001 occurs as clusters within orthopyroxene adjacent to fractures containing disrupted carbonate globules and feldspathic shock glass. The inclusions are irregular in shape and range in size from approx. 40 microns to submicrometer. Some of the inclusions are elongate and boudinage-like. The olivine grains are in sharp contact with the enclosing orthopyroxene and often contain small inclusions of chromite The olivine exhibits a very limited range of composition from Fo(sub 65) to Fo(sub 66) (n = 25). The delta(sup 18)O values of the olivine and orthopyroxene analyzed by ion microprobe range from +4.3 to +5.3% and are indistinguishable from each other within analytical uncertainty. The mineral chemistries, O-isotopic data, and textural relationships indicate that the olivine inclusions were produced at a temperature greater than 800 C. It is unlikely that the olivines formed during the same event that gave rise to the carbonates in ALH 84001, which have more elevated and variable delta(sup 18)O values, and were probably formed from fluids that were not in isotopic equilibrium with the orthopyroxene or olivine The reactions most likely instrumental in the formation of olivine could be either the dehydration of hydrous silicates that formed during carbonate precipitation or the reduction of orthopyroxene and spinel If the olivine was formed by either reaction during a postcarbonate beating event, the implications are profound with regards to the interpretations of McKay et al. Due to the low diffusion rates in carbonates, this rapid, high-temperature event would have resulted in the preservation of the fine-scale carbonate zoning' while partially devolatilizing select carbonate compositions on a submicrometer scale. This may have resulted in the formation of the minute magnetite grains that McKay et al attributed to biogenic activity.

  4. Meta-analytic evidence for decreased heart rate variability in chronic pain implicating parasympathetic nervous system dysregulation.

    PubMed

    Tracy, Lincoln M; Ioannou, Liane; Baker, Katharine S; Gibson, Stephen J; Georgiou-Karistianis, Nellie; Giummarra, Melita J

    2016-01-01

    Both sympathetic and parasympathetic nervous systems are involved in regulating pain states. The activity of these systems seems to become disturbed in states of chronic pain. This disruption in autonomic balance can be measured through the assessment of heart rate variability (HRV), that is, the variability of the interval between consecutive heart beats. However, there is yet to be a systematic evaluation of the body of literature concerning HRV across several chronic pain conditions. Moreover, modern meta-analytical techniques have never been used to validate and consolidate the extent to which HRV may be decreased in chronic pain. Following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) statement guidelines, this study systematically evaluated and critically appraised the literature concerning HRV in people living with chronic pain. After screening 17,350 sources, 51 studies evaluating HRV in a chronic pain group met the inclusion criteria. Twenty-six moderate-high quality studies were included in quantitative meta-analyses. On average, the quality of studies was moderate. There were 6 frequency-domain and time-domain measures of HRV across a broad range of chronic pain conditions. High heterogeneity aside, pooled results from the meta-analyses reflected a consistent, moderate-to-large effect of decreased high-frequency HRV in chronic pain, implicating a decrease in parasympathetic activation. These effects were heavily influenced by fibromyalgia studies. Future research would benefit from wider use of standardised definitions of measurement, and also investigating the synergistic changes in pain state and HRV throughout the development and implementation of mechanism-based treatments for chronic pain.

  5. Global warming: the balance of evidence and its policy implications. A review of the current state-of-the-controversy.

    PubMed

    Keller, Charles F

    2003-05-05

    Global warming and attendant climate change have been controversial for at least a decade. This is largely because of its societal implications. With the recent publication of the Third Assessment Report of the United Nations' Intergovernmental Panel on Climate Change there has been renewed interest and controversy about how certain the scientific community is of its conclusions: that humans are influencing the climate and that global temperatures will continue to rise rapidly in this century. This review attempts to update what is known and in particular what advances have been made in the past 5 years or so. It does not attempt to be comprehensive. Rather it focuses on the most controversial issues, which are actually few in number. They are: Is the surface temperature record accurate or is it biased by heat from cities, etc.?, Is that record significantly different from past warmings such as the Medieval Warming Period?, Is not the sun's increasing activity the cause of most of the warming?, Can we model climate and predict its future, or is it just too complex and chaotic?, Are there any other changes in climate other than warming, and can they be attributed to the warming? Despite continued uncertainties, the review finds affirmative answers to these questions. Of particular interest are advances that seem to explain why satellites do not see as much warming as surface instruments, how we are getting a good idea of recent paleoclimates, and why the 20th century temperature record was so complex. It makes the point that in each area new information could come to light that would change our thinking on the quantitative magnitude and timing of anthropogenic warming, but it is unlikely to alter the basic conclusions. Finally, there is a very brief discussion of the societal policy response to the scientific message, and the author comments on his 2-year email discussions with many of the world's most outspoken critics of the anthropogenic warming hypothesis.

  6. No evidence that protein truncating variants in BRIP1 are associated with breast cancer risk: implications for gene panel testing

    PubMed Central

    Easton, Douglas F; Lesueur, Fabienne; Decker, Brennan; Michailidou, Kyriaki; Li, Jun; Allen, Jamie; Luccarini, Craig; Pooley, Karen A; Shah, Mitul; Bolla, Manjeet K; Wang, Qin; Dennis, Joe; Ahmad, Jamil; Thompson, Ella R; Damiola, Francesca; Pertesi, Maroulio; Voegele, Catherine; Mebirouk, Noura; Robinot, Nivonirina; Durand, Geoffroy; Forey, Nathalie; Luben, Robert N; Ahmed, Shahana; Aittomäki, Kristiina; Anton-Culver, Hoda; Arndt, Volker; Baynes, Caroline; Beckman, Matthias W; Benitez, Javier; Van Den Berg, David; Blot, William J; Bogdanova, Natalia V; Bojesen, Stig E; Brenner, Hermann; Chang-Claude, Jenny; Chia, Kee Seng; Choi, Ji-Yeob; Conroy, Don M; Cox, Angela; Cross, Simon S; Czene, Kamila; Darabi, Hatef; Devilee, Peter; Eriksson, Mikael; Fasching, Peter A; Figueroa, Jonine; Flyger, Henrik; Fostira, Florentia; García-Closas, Montserrat; Giles, Graham G; Glendon, Gord; González-Neira, Anna; Guénel, Pascal; Haiman, Christopher A; Hall, Per; Hart, Steven N; Hartman, Mikael; Hooning, Maartje J; Hsiung, Chia-Ni; Ito, Hidemi; Jakubowska, Anna; James, Paul A; John, Esther M; Johnson, Nichola; Jones, Michael; Kabisch, Maria; Kang, Daehee; Kosma, Veli-Matti; Kristensen, Vessela; Lambrechts, Diether; Li, Na; Lindblom, Annika; Long, Jirong; Lophatananon, Artitaya; Lubinski, Jan; Mannermaa, Arto; Manoukian, Siranoush; Margolin, Sara; Matsuo, Keitaro; Meindl, Alfons; Mitchell, Gillian; Muir, Kenneth; Nevelsteen, Ines; van den Ouweland, Ans; Peterlongo, Paolo; Phuah, Sze Yee; Pylkäs, Katri; Rowley, Simone M; Sangrajrang, Suleeporn; Schmutzler, Rita K; Shen, Chen-Yang; Shu, Xiao-Ou; Southey, Melissa C; Surowy, Harald; Swerdlow, Anthony; Teo, Soo H; Tollenaar, Rob A E M; Tomlinson, Ian; Torres, Diana; Truong, Thérèse; Vachon, Celine; Verhoef, Senno; Wong-Brown, Michelle; Zheng, Wei; Zheng, Ying; Nevanlinna, Heli; Scott, Rodney J; Andrulis, Irene L; Wu, Anna H; Hopper, John L; Couch, Fergus J; Winqvist, Robert; Burwinkel, Barbara; Sawyer, Elinor J; Schmidt, Marjanka K; Rudolph, Anja; Dörk, Thilo; Brauch, Hiltrud; Hamann, Ute; Neuhausen, Susan L; Milne, Roger L; Fletcher, Olivia; Pharoah, Paul D P; Campbell, Ian G; Dunning, Alison M; Le Calvez-Kelm, Florence; Goldgar, David E; Tavtigian, Sean V; Chenevix-Trench, Georgia

    2016-01-01

    Background BRCA1 interacting protein C-terminal helicase 1 (BRIP1) is one of the Fanconi Anaemia Complementation (FANC) group family of DNA repair proteins. Biallelic mutations in BRIP1 are responsible for FANC group J, and previous studies have also suggested that rare protein truncating variants in BRIP1 are associated with an increased risk of breast cancer. These studies have led to inclusion of BRIP1 on targeted sequencing panels for breast cancer risk prediction. Methods We evaluated a truncating variant, p.Arg798Ter (rs137852986), and 10 missense variants of BRIP1, in 48 144 cases and 43 607 controls of European origin, drawn from 41 studies participating in the Breast Cancer Association Consortium (BCAC). Additionally, we sequenced the coding regions of BRIP1 in 13 213 cases and 5242 controls from the UK, 1313 cases and 1123 controls from three population-based studies as part of the Breast Cancer Family Registry, and 1853 familial cases and 2001 controls from Australia. Results The rare truncating allele of rs137852986 was observed in 23 cases and 18 controls in Europeans in BCAC (OR 1.09, 95% CI 0.58 to 2.03, p=0.79). Truncating variants were found in the sequencing studies in 34 cases (0.21%) and 19 controls (0.23%) (combined OR 0.90, 95% CI 0.48 to 1.70, p=0.75). Conclusions These results suggest that truncating variants in BRIP1, and in particular p.Arg798Ter, are not associated with a substantial increase in breast cancer risk. Such observations have important implications for the reporting of results from breast cancer screening panels. PMID:26921362

  7. Global warming: the balance of evidence and its policy implications. A review of the current state-of-the-controversy.

    PubMed

    Keller, Charles F

    2003-05-01

    Global warming and attendant climate change have been controversial for at least a decade. This is largely because of its societal implications. With the recent publication of the Third Assessment Report of the United Nations' Intergovernmental Panel on Climate Change there has been renewed interest and controversy about how certain the scientific community is of its conclusions: that humans are influencing the climate and that global temperatures will continue to rise rapidly in this century. This review attempts to update what is known and in particular what advances have been made in the past 5 years or so. It does not attempt to be comprehensive. Rather it focuses on the most controversial issues, which are actually few in number. They are: Is the surface temperature record accurate or is it biased by heat from cities, etc.?, Is that record significantly different from past warmings such as the Medieval Warming Period?, Is not the sun's increasing activity the cause of most of the warming?, Can we model climate and predict its future, or is it just too complex and chaotic?, Are there any other changes in climate other than warming, and can they be attributed to the warming? Despite continued uncertainties, the review finds affirmative answers to these questions. Of particular interest are advances that seem to explain why satellites do not see as much warming as surface instruments, how we are getting a good idea of recent paleoclimates, and why the 20th century temperature record was so complex. It makes the point that in each area new information could come to light that would change our thinking on the quantitative magnitude and timing of anthropogenic warming, but it is unlikely to alter the basic conclusions. Finally, there is a very brief discussion of the societal policy response to the scientific message, and the author comments on his 2-year email discussions with many of the world's most outspoken critics of the anthropogenic warming hypothesis. PMID

  8. Evidence for and implications of sedimentary diapirism and mud volcanism in the southern Utopia highland-lowland boundary plain, Mars

    USGS Publications Warehouse

    Skinner, J.A.; Tanaka, K.L.

    2007-01-01

    which detritus would have accumulated thickly in the annular spaces between impact-generated structural rings of Utopia basin. We envision that these materials, and perhaps buried ejecta of Utopia basin, contained volatile-rich, low-density material that could provide the source material for the postulated sedimentary diapirs. Thick, water-rich, low-density sediments buried elsewhere along the HLB and within the lowland plains may account for similar landforms and resurfacing histories. ?? 2006 Elsevier Inc. All rights reserved.

  9. Explaining variations in state foster care maintenance rates and the implications for implementing new evidence-based programs

    PubMed Central

    Goldhaber-Fiebert, Jeremy D.; Babiarz, Kimberly S.; Garfield, Rachel L.; Wulczyn, Fred; Landsverk, John; Horwitz, Sarah M.

    2013-01-01

    Background U.S. Child Welfare systems are involved in the lives of millions of children, and total spending exceeds $26 billion annually. Out-of-home foster care is a critical and expensive Child Welfare service, a major component of which is the maintenance rate paid to support housing and caring for a foster child. Maintenance rates vary widely across states and over time, but reasons for this variation are not well understood. As evidence-based programs are disseminated to state Child Welfare systems, it is important to understand what may be the important drivers in the uptake of these practices including state spending on core system areas. Data and methods We assembled a unique, longitudinal, state-level panel dataset (1990–2008) for all 50 states with annual data on foster care maintenance rates and measures of child population in need, poverty, employment, urbanicity, proportion minority, political party control of the state legislature and governorship, federal funding, and lawsuits involving state foster care systems. All monetary values were expressed in per-capita terms and inflation adjusted to 2008 dollars. We used longitudinal panel regressions with robust standard errors and state and year fixed effects to estimate the relationship between state foster care maintenance rates and the other factors in our dataset, lagging all factors by one year to mitigate the possibility that maintenance rates influenced their predictors. Exploratory analyses related maintenance rates to Child Welfare outcomes. Findings State foster care maintenance rates have increased in nominal terms, but in many states, have not kept pace with inflation, leading to lower real rates in 2008 compared to those in 1991 for 54% of states for 2 year-olds, 58% for 9 year-olds, and 65% for 16 year-olds. In multivariate analyses including socioeconomic, demographic, and political factors, monthly foster care maintenance rates declined $15 for each 1% increase in state unemployment and

  10. A Direct Experimental Evidence For the New Thermodynamic Boundary in the Supercritical State: Implications for Earth and Planetary Sciences.

    NASA Astrophysics Data System (ADS)

    Bolmatov, D.

    2015-12-01

    While scientists have a good theoretical understanding of the heat capacity of both solids and gases, a general theory of the heat capacity of liquids has always remained elusive. Apart from being an awkward hole in our knowledge, heat capacity - the amount of heat needed to change a substance's temperature by a certain amount - is a relevant quantity that it would be nice to be able to predict. I will introduce a phonon-based approach to liquids and supercritical fluids to describe its thermodynamics in terms of sound propagation. I will show that the internal liquid energy has a transverse sound propagation gaps and explain their evolution with temperature variations on the P-T diagram. I will explain how this theoretical framework covers the Debye theory of solids, the phonon theory of liquids, and thermodynamic limits such as the Delong-Petit and the ideal gas thermodynamic limits. As a results, the experimental evidence for the new thermodynamic boundary in the supercritical state (the Frenkel line) on the P-T phase diagram will be demonstrated. Then, I will report on inelastic X-ray scattering experiments combined with the molecular dynamics simulations on deeply supercritical Ar. The presented results unveil the mechanism and regimes of sound propagation in the liquid matter and provide compelling evidence for the adiabatic-to-isothermal longitudinal sound propagation transition. As a result, a universal link will be demonstrated between the positive sound dispersion (PSD) phenomenon and the origin of transverse sound propagation revealing the viscous-to-elastic crossover in compressed liquids. Both can be considered as a universal fingerprint of the dynamic response of a liquid. They can be used then for a signal detection and analysis of a dynamic response in deep water and other fluids which is relevant for describing the thermodynamics of gas giants. The consequences of this finding will be discussed, including a physically justified way to demarcate the

  11. Holocene extreme hydrological events and their climatic implications: evidence from the middle Satluj valley, western Himalaya, India

    NASA Astrophysics Data System (ADS)

    Sharma, Shubhra; Shukla, Anil; Marh, Bhupinder; Bartarya, Sukesh; Juyal, Navin

    2016-04-01

    Extreme hydrological events and associated climatic processes are investigated and inferred through palaeoflood deposits preserved in the middle Satluj valley, India. Satluj River is the largest tributary of the Indus River having third largest catchment area in the Himalaya. Both Indian summer monsoon (ISM) and the mid-latitude westerlies contribute to the hydrological budget of the river. The steep southern orographic front prevents the northward penetration of ISM, while the mid-latitude westerlies bring moisture in form of winter snow to the orogenic interiors. It has been observed that the floods in the Himalaya are intimately associated with the variability in the above climate systems. The optical chronology indicates that floods were clustered around three time domains. The oldest flood phase-1 is dated to ˜14-12 ka which climatically occurred during the initiation of the ISM after the Last Glacial Maximum. The second phase-2 is dated between 8-5 ka and is attributed to the moderate ISM. Whereas, the youngest phase-3 is assigned the Little Ice Age (LIA) and were associated with the variability in the mid-latitude westerlies. Geochemical analyses suggest that floods were generated in higher Himalayan crystalline (HHC) zone, as the extreme precipitation destabilised the precipitous slopes creating Landslide induced Lake Outbursts Floods (LLOFs). Further, the average interval between floods has decreased since 14 ka from 500 years, to 250 years and 100 years during respective flood phases. The southern slopes of Himalaya are influenced by both the monsoon and mid-latitude westerlies and any abrupt changes in the circulation pattern were found to associate with heavy rainfall events in this region. Although an interaction between the westerlies and the monsoon is implicated for extreme floods in the western Himalaya. However, exact mechanism of these interactions is still illusive except for the observational based studies which state that extreme floods

  12. Evidence of cave use by savanna chimpanzees (Pan troglodytes verus) at Fongoli, Senegal: implications for thermoregulatory behavior.

    PubMed

    Pruetz, J D

    2007-10-01

    Much attention has been paid to how humans both adapt and acclimate to heat stress, primarily due to the relevance of these issues to hominid evolution in open Plio-Pleistocene environments. However, little is known about the responses of human's closest living relative, the chimpanzee (Pan troglodytes), to similar environmental stressors. In southeastern Senegal, one of the hottest and driest habitats that chimpanzees (P. t. verus) live in today, apes rely on behavioral mechanisms of dealing with thermal stress. Chimpanzees' use of caves was based primarily on indirect evidence (feeding traces, feces, and hairs) gathered from one cave from January to December 2004, but data from observational records collected from May 2001 through March 2006 supplement these data. The hypothesis that chimpanzees' use of caves is a response to heat was tested by collecting data on temperatures within the largest cave and in different habitats used by chimpanzees, such as gallery forest and woodland. Results indicate that chimpanzees primarily use caves as shelters during the hottest times of year and that caves are consistently and significantly cooler than open habitats. Insight into the way that chimpanzees in Senegal cope with extreme temperatures may help us to better understand the behavior of early hominids in such an environment.

  13. How clinicians make (or avoid) moral judgments of patients: implications of the evidence for relationships and research

    PubMed Central

    2010-01-01

    Physicians, nurses, and other clinicians readily acknowledge being troubled by encounters with patients who trigger moral judgments. For decades social scientists have noted that moral judgment of patients is pervasive, occurring not only in egregious and criminal cases but also in everyday situations in which appraisals of patients' social worth and culpability are routine. There is scant literature, however, on the actual prevalence and dynamics of moral judgment in healthcare. The indirect evidence available suggests that moral appraisals function via a complex calculus that reflects variation in patient characteristics, clinician characteristics, task, and organizational factors. The full impact of moral judgment on healthcare relationships, patient outcomes, and clinicians' own well-being is yet unknown. The paucity of attention to moral judgment, despite its significance for patient-centered care, communication, empathy, professionalism, healthcare education, stereotyping, and outcome disparities, represents a blind spot that merits explanation and repair. New methodologies in social psychology and neuroscience have yielded models for how moral judgment operates in healthcare and how research in this area should proceed. Clinicians, educators, and researchers would do well to recognize both the legitimate and illegitimate moral appraisals that are apt to occur in healthcare settings. PMID:20618947

  14. Changing healthcare capital-to-labor ratios: evidence and implications for bending the cost curve in Canada and beyond.

    PubMed

    Nauenberg, Eric

    2014-12-01

    Healthcare capital-to-labor ratios are examined for the 10 provincial single-payer health care plans across Canada. The data show an increasing trend-particularly during the period 1997-2009 during which the ratio as much as doubled from 3 to 6 %. Multivariate analyses indicate that every percentage point uptick in the rate of increase in this ratio is associated with an uptick in the rate of increase of real per capita provincial government healthcare expenditures by approximately $31 ([Formula: see text] 0.01). While the magnitude of this relationship is not large, it is still substantial enough to warrant notice: every percentage point decrease in the upward trend of the capital-to-labor ratio might be associated with a one percentage point decrease in the upward trend of per capita government healthcare expenditures. An uptick since 1997 in the rate of increase in per capita prescription drug expenditures is also associated with a decline in the trend of increasing per capita healthcare costs. While there has been some recent evidence of a slowing in the rate of health care expenditure increase, it is still unclear whether this reflects just a pause, after which the rate of increase will return to its baseline level, or a long-term shift; therefore, it is important to continue to explore various policy avenues to affect the rate of change going forward. PMID:25129110

  15. The Protective Role of Positive Well-Being in Cardiovascular Disease: Review of Current Evidence, Mechanisms, and Clinical Implications.

    PubMed

    Sin, Nancy L

    2016-11-01

    Positive psychological aspects of well-being-including positive emotions, optimism, and life satisfaction-are increasingly considered to have protective roles for cardiovascular disease (CVD) and longevity. A rapidly-growing body of literature has linked positive well-being with better cardiovascular health, lower incidence of CVD in healthy populations, and reduced risk of adverse outcomes in patients with existing CVD. This review first examines evidence on the associations of positive well-being with CVD and mortality, focusing on recent epidemiological research as well as inconsistent findings. Next, an overview is provided of putative biological, behavioral, and stress-buffering mechanisms that may underlie the relationship between positive well-being and cardiovascular health. Key areas for future inquiry are discussed, in addition to emerging developments that capitalize on technological and methodological advancements. Promising initial results from randomized controlled trials suggest that efforts to target positive well-being may serve as valuable components of broader CVD management programs. PMID:27612475

  16. Evidence for skipped spawning in a potamodromous cyprinid, humpback chub (Gila cypha), with implications for demographic parameter estimates

    USGS Publications Warehouse

    Pearson, Kristen Nicole; Kendall, William; Winkelman, Dana L.; Persons, William R.

    2015-01-01

    Our findings reveal evidence for skipped spawning in a potamodromous cyprinid, humpback chub (HBC; Gila cypha  ). Using closed robust design mark-recapture models, we found, on average, spawning HBC transition to the skipped spawning state () with a probability of 0.45 (95% CRI (i.e. credible interval): 0.10, 0.80) and skipped spawners remain in the skipped spawning state () with a probability of 0.60 (95% CRI: 0.26, 0.83), yielding an average spawning cycle of every 2.12 years, conditional on survival. As a result, migratory skipped spawners are unavailable for detection during annual sampling events. If availability is unaccounted for, survival and detection probability estimates will be biased. Therefore, we estimated annual adult survival probability (S), while accounting for skipped spawning, and found S remained reasonably stable throughout the study period, with an average of 0.75 ((95% CRI: 0.66, 0.82), process varianceσ2 = 0.005), while skipped spawning probability was highly dynamic (σ2 = 0.306). By improving understanding of HBC spawning strategies, conservation decisions can be based on less biased estimates of survival and a more informed population model structure.

  17. Seismic evidence for the North China plate underthrusting beneath northeastern Tibet and its implications for plateau growth

    NASA Astrophysics Data System (ADS)

    Ye, Zhuo; Gao, Rui; Li, Qiusheng; Zhang, Hongshuang; Shen, Xuzhang; Liu, Xuzhou; Gong, Chen

    2015-09-01

    Lithospheric deformation of the Tibetan plateau is caused by subduction of the Indian (northward) and Asian (southward) plates. The effects of this interaction on inner reaches of the Asian continent, between the Tibetan plateau and the North China craton (NCC) for example, remain uncertain due to poor geophysical data coverage in northeastern Tibet (NE Tibet). We provide here detailed knowledge of the lithospheric structure beneath NE Tibet as determined from a dense broadband seismic profile traversing NE Tibet to the westernmost NCC. Receiver function imaging reveals several significant features, including a north-dipping intracrustal converter (NC), Moho offset/overlap beneath major fault zones, and a low velocity layer (LVL) in the middle-lower crust. The lithosphere-asthenosphere boundary (LAB) is clearly defined and appears as a south-dipping interface that runs continuously from the Alxa interior to the Qilian orogen. Interpretation of these observations, combined with other seismic evidence, implies that the NCC lithospheric mantle has been persistently underthrust beneath the Qilian orogen. This process forms the thick-skinned crustal accretionary wedges, which develop above a middle-lower intracrustal decollement. Our results provide further deep-geophysical constraints on the Cenozoic post-collisional evolution of the convergent boundary between NE Tibet and the NCC and help clarify the mechanism of plateau growth in this boundary area.

  18. Changing healthcare capital-to-labor ratios: evidence and implications for bending the cost curve in Canada and beyond.

    PubMed

    Nauenberg, Eric

    2014-12-01

    Healthcare capital-to-labor ratios are examined for the 10 provincial single-payer health care plans across Canada. The data show an increasing trend-particularly during the period 1997-2009 during which the ratio as much as doubled from 3 to 6 %. Multivariate analyses indicate that every percentage point uptick in the rate of increase in this ratio is associated with an uptick in the rate of increase of real per capita provincial government healthcare expenditures by approximately $31 ([Formula: see text] 0.01). While the magnitude of this relationship is not large, it is still substantial enough to warrant notice: every percentage point decrease in the upward trend of the capital-to-labor ratio might be associated with a one percentage point decrease in the upward trend of per capita government healthcare expenditures. An uptick since 1997 in the rate of increase in per capita prescription drug expenditures is also associated with a decline in the trend of increasing per capita healthcare costs. While there has been some recent evidence of a slowing in the rate of health care expenditure increase, it is still unclear whether this reflects just a pause, after which the rate of increase will return to its baseline level, or a long-term shift; therefore, it is important to continue to explore various policy avenues to affect the rate of change going forward.

  19. Airborne radar evidence for tributary flow switching in Institute Ice Stream, West Antarctica: Implications for ice sheet configuration and dynamics

    NASA Astrophysics Data System (ADS)

    Winter, Kate; Woodward, John; Ross, Neil; Dunning, Stuart A.; Bingham, Robert G.; Corr, Hugh F. J.; Siegert, Martin J.

    2015-09-01

    Despite the importance of ice streaming to the evaluation of West Antarctic Ice Sheet (WAIS) stability we know little about mid- to long-term dynamic changes within the Institute Ice Stream (IIS) catchment. Here we use airborne radio echo sounding to investigate the subglacial topography, internal stratigraphy, and Holocene flow regime of the upper IIS catchment near the Ellsworth Mountains. Internal layer buckling within three discrete, topographically confined tributaries, through Ellsworth, Independence, and Horseshoe Valley Troughs, provides evidence for former enhanced ice sheet flow. We suggest that enhanced ice flow through Independence and Ellsworth Troughs, during the mid-Holocene to late Holocene, was the source of ice streaming over the region now occupied by the slow-flowing Bungenstock Ice Rise. Although buckled layers also exist within the slow-flowing ice of Horseshoe Valley Trough, a thicker sequence of surface-conformable layers in the upper ice column suggests slowdown more than ~4000 years ago, so we do not attribute enhanced flow switch-off here, to the late Holocene ice-flow reorganization. Intensely buckled englacial layers within Horseshoe Valley and Independence Troughs cannot be accounted for under present-day flow speeds. The dynamic nature of ice flow in IIS and its tributaries suggests that recent ice stream switching and mass changes in the Siple Coast and Amundsen Sea sectors are not unique to these sectors, that they may have been regular during the Holocene and may characterize the decline of the WAIS.

  20. Tax, price and cigarette smoking: evidence from the tobacco documents and implications for tobacco company marketing strategies

    PubMed Central

    Chaloupka, F; Cummings, K; Morley, C.; Horan, J.

    2002-01-01

    Methods: Data for this study come from tobacco industry documents contained in the Youth and Marketing database created by the Roswell Park Cancer Institute and available through http:// roswell.tobaccodocuments.org, supplemented with documents obtained from http://www.tobaccodocuments.org. Results: Tobacco company documents provide clear evidence on the impact of cigarette prices on cigarette smoking, describing how tax related and other price increases lead to significant reductions in smoking, particularly among young persons. This information was very important in developing the industry's pricing strategies, including the development of lower price branded generics and the pass through of cigarette excise tax increases, and in developing a variety of price related marketing efforts, including multi-pack discounts, couponing, and others. Conclusions: Pricing and price related promotions are among the most important marketing tools employed by tobacco companies. Future tobacco control efforts that aim to raise prices and limit price related marketing efforts are likely to be important in achieving reductions in tobacco use and the public health toll caused by tobacco. PMID:11893816

  1. Characterization of Cd translocation and accumulation in 19 maize cultivars grown on Cd-contaminated soil: implication of maize cultivar selection for minimal risk to human health and for phytoremediation.

    PubMed

    Wang, Aiyun; Wang, Minyan; Liao, Qi; He, Xiquan

    2016-03-01

    Maize (Zea mays) has low Cd accumulation in grains and a high biomass compared to other crops. The capacities for Cd accumulation in different maize cultivars are, however, not fully understood. To reduce human health risk from maize grown in Cd-contaminated soil and to provide promising maize cultivars for the phytoremediation of Cd-polluted soil, a field experiment was conducted to screen low-Cd- and high-Cd-accumulation maize cultivars by evaluating the yield, Cd uptake, translocation, and accumulation differences among 19 maize cultivars. There were differences in straw dry weight (DW), root DW, and yield among the 19 cultivars. The cultivars Yudan19, Zhengda999, and Xianyu508 had a higher production compared to that of the other cultivars. The Cd concentrations in the roots were much higher than those in the straws and grains in all cultivars. The Cd accumulation factors (AFS) decreased in the order of accumulation factors in root (AFrs) > accumulation factors in straw (AFss) > accumulation factors in grain (AFgs). The Cd translocation factors (TFs) from root to straw (TFrs) were significantly (p < 0.05) larger than those from straw to grain (TFsg) among all of the cultivars. The TFs for all of the cultivars was less than 1, and the lowest TFsg (0.23) was found in cultivar Xiangyongdan3. The correlation analysis indicated that Cd concentrations in straws showed a significant (p < 0.01) as well as positive correlation with TFrs while a negative correlation with TFsg (p < 0.01). Moreover, Cd accumulation in different tissues decreased in the order straw > grain > root. Among the 19 maize cultivars, Jixiang2118 and Kangnong18 accumulated the highest Cd amount in the aboveground tissues, and the corresponding values were 7,206.51 and 6,598.68 mg hm(-2), respectively. A hierarchical cluster analysis based on the Cd concentrations in grains and straws classified the 19 maize cultivars into four and two groups for a 0.4 minimum distance between clusters

  2. Structural and thermal development of the Atlantic margin offshore Essaouira (Morocco) - evidence of salt extrusion and implications for hydrocarbon exploration

    NASA Astrophysics Data System (ADS)

    Neumaier, Martin; Littke, Raf; Kleine, Adrian; Schnabel, Michael; Reichert, Christian

    2013-04-01

    Along the east-west regional seismic line BGR11-202 (MIRROR campaign, 2011), several distinct salt diapirs and related structures can be identified close to the present day coast line. The subsalt structure is only very poorly imaged. Further offshore, rotated fault blocks are overlain by Mesozoic and Cenozoic sediments. Towards the west, the evidence for past volcanic activity is increasing (necks, dykes, and sills). The magnetic anomaly S1 is roughly situated west of the most western identifiable salt structure. The aim of our study is to describe and verify possible salt tectonic and related thermal models and the evolution of the petroleum systems. One salt structure in particular shows clear evidence of salt extrusion in the past. We explain the potential scenario of the salt diapir development and extrusion in a series of structurally restored sections: After deposition, probably within the syn-rift Liassic half grabens (not imaged), the salt quickly became instable due to differential loading, assisted by growing density contrast with the overburden. It forced its way up using weak zones—which could have been the active normal faults—while the overburden collapsed into the previously occupied space (salt withdrawal). Even though the salt was constantly rising, it did not reach the surface due to constant burial. Only once the sedimentation rate decreased—during the late Cretaceous and early Paleogene—the salt extruded and crept down the continental slope onto the hiatus unconformity. With the extrusion, the salt partly dissolved in contact with the ocean water, and a cap rock formed. The related paleorelief was buried by the detritical sediments provided by the Atlas orogenesis. At present day, these paleoreliefs still have a bathymetric expression, as they are providing an unstable underground and trigger normal faulting and local resedimentation. Also remobilization of the salt, even though strengthened by the cap rock, might be possible locally

  3. Executive Function Skills of 6 to 8 Year Olds: Brain and Behavioral Evidence and Implications for School Achievement

    PubMed Central

    Molfese, Victoria J.; Molfese, Peter J.; Molfese, Dennis L.; Rudasill, Kathleen M.; Armstrong, Natalie; Starkey, Gillian

    2010-01-01

    Academic and social success in school has been linked to children’s self-regulation. This study investigated the assessment of the executive function (EF) component of self-regulation using a low-cost, easily administered measure to determine whether scores obtained from the behavioral task would agree with those obtained using a laboratory-based neuropsychological measure of EF skills. The sample included 74 children (37 females; M = 86.2 months) who participated in two assessments of working memory and inhibitory control: Knock-Tap (NEPSY: Korkman, Kirk, and Kemp, 1998), and participation in event-related potential (ERP) testing that included the Directional Stroop Test (Davidson, Cruess, Diamond, O’Craven, & Savoy, 1999). Three main findings emerged. First, children grouped as high versus low performing on the NEPSY Knock-Tap Task were found to performed differently on the more difficult conditions of the DST (the Incongruent and Mixed Conditions), suggesting that the Knock-Tap Task as a low-cost and easy to administer assessment of EF skills may be one way for teachers to identify students with poor inhibitory control skills. Second, children’s performance on the DST was strongly related to their ERP responses, adding to evidence that differences in behavioral performance on the DST as a measure of EF skills reflect corresponding differences in brain processing. Finally, differences in brain processing on the DST task also were found when the children were grouped based on Knock-Tap performance. Simple screening procedures can enable teachers to identify children whose distractibility, inattentiveness, or poor attention spans may interfere with classroom learning. PMID:20798857

  4. Evidence for biogenic processes during formation of ferromanganese crusts from the Pacific Ocean: implications of biologically induced mineralization.

    PubMed

    Wang, Xiao-Hong; Schlossmacher, Ute; Natalio, Filipe; Schröder, Heinz C; Wolf, Stephan E; Tremel, Wolfgang; Müller, Werner E G

    2009-01-01

    Ferromanganese [Fe/Mn] crusts formed on basaltic seamounts, gain considerable economic importance due to their high content of Co, Ni, Cu, Zn and Pt. The deposits are predominantly found in the Pacific Ocean in depths of over 1000m. They are formed in the mixing layer between the upper oxygen-minimum zone and the lower oxygen-rich bottom zone. At present an almost exclusive abiogenic origin of crust formation is considered. We present evidence that the upper layers of the crusts from the Magellan Seamount cluster are very rich in coccoliths/coccolithophores (calcareous phytoplankton) belonging to different taxa. Rarely intact skeletons of these unicellular algae are found, while most of them are disintegrated into their composing prisms or crystals. Studies on the chemical composition of crust samples by high resolution SEM combined with an electron probe microanalyzer (EPMA) revealed that they are built of distinct stacked piles of individual compartments. In the center of such piles Mn is the dominant element, while the rims of the piles are rich in Fe (mineralization aspect). The compartments contain coccospheres usually at the basal part. Energy dispersive X-ray spectroscopy (EDX) analyses showed that those coccospheres contain, as expected, CaCO3 but also Mn-oxide. Detailed analysis displayed on the surface of the coccolithophores a high level of CaCO3 while the concentration of Mn-oxide is relatively small. With increasing distance from the coccolithophores the concentration of Mn-oxide increases on the expense of residual CaCO3. We conclude that coccoliths/coccolithophores are crucial for the seed/nucleation phase of crust formation (biomineralization aspect). Subsequently, after the biologically induced mineralization phase Mn-oxide deposition proceeds "auto"catalytically. PMID:19443230

  5. Convergent evidences from human and animal studies implicate angiotensin I-converting enzyme activity in cognitive performance in schizophrenia

    PubMed Central

    Gadelha, A; Vendramini, A M; Yonamine, C M; Nering, M; Berberian, A; Suiama, M A; Oliveira, V; Lima-Landman, M T; Breen, G; Bressan, R A; Abílio, V; Hayashi, M A F

    2015-01-01

    In schizophrenia (SCZ), higher angiotensin I-converting enzyme (ACE) levels have been reported in patient's blood and cerebrospinal fluid (CSF). Hereby, we propose to explore whether the ACE activity levels are associated to cognitive performance in SCZ. Seventy-two patients with SCZ or schizoaffective disorder diagnosis, and 69 healthy controls (HCs) underwent a cognitive battery with parallel collection of peripheral blood samples to measure ACE activity. Significant higher ACE activity levels were confirmed in the plasma of SCZ patients compared with HCs (Student's t=−5.216; P<0.001). ACE activity significantly correlated to Hopkins delayed recall measures (r=−0.247; P=0.004) and Hopkins total (r=−0.214; P=0.012). Subjects grouped as high ACE activity (above average) had worse performance compared with low ACE activity level group for Hopkins delayed recall measure, even after correction for clinical condition, age, gender and years of education (P=0.029). The adjusted R squared for this final model was 0.343. This result was evident only comparing extreme groups for ACE activity, when splitting the sample in three groups with similar number of subjects. To clarify this finding, we performed an evaluation of the cognitive performance of transgenic mice with three copies of ACE gene in novel object recognition (NOR) test, which showed that such animals presented impairment in NOR (P<0.05) compared with two copies of wild-type animals. The results observed in SCZ patients and animal model suggest both the association of ACE to cognitive deficits in SCZ. This finding may support the evaluation of novel treatment protocols and/or of innovative drugs for specific intervention of cognitive deficits in SCZ envisioning concomitant ACE activity and behavior evaluations. PMID:26645626

  6. Evidence for biogenic processes during formation of ferromanganese crusts from the Pacific Ocean: implications of biologically induced mineralization.

    PubMed

    Wang, Xiao-Hong; Schlossmacher, Ute; Natalio, Filipe; Schröder, Heinz C; Wolf, Stephan E; Tremel, Wolfgang; Müller, Werner E G

    2009-01-01

    Ferromanganese [Fe/Mn] crusts formed on basaltic seamounts, gain considerable economic importance due to their high content of Co, Ni, Cu, Zn and Pt. The deposits are predominantly found in the Pacific Ocean in depths of over 1000m. They are formed in the mixing layer between the upper oxygen-minimum zone and the lower oxygen-rich bottom zone. At present an almost exclusive abiogenic origin of crust formation is considered. We present evidence that the upper layers of the crusts from the Magellan Seamount cluster are very rich in coccoliths/coccolithophores (calcareous phytoplankton) belonging to different taxa. Rarely intact skeletons of these unicellular algae are found, while most of them are disintegrated into their composing prisms or crystals. Studies on the chemical composition of crust samples by high resolution SEM combined with an electron probe microanalyzer (EPMA) revealed that they are built of distinct stacked piles of individual compartments. In the center of such piles Mn is the dominant element, while the rims of the piles are rich in Fe (mineralization aspect). The compartments contain coccospheres usually at the basal part. Energy dispersive X-ray spectroscopy (EDX) analyses showed that those coccospheres contain, as expected, CaCO3 but also Mn-oxide. Detailed analysis displayed on the surface of the coccolithophores a high level of CaCO3 while the concentration of Mn-oxide is relatively small. With increasing distance from the coccolithophores the concentration of Mn-oxide increases on the expense of residual CaCO3. We conclude that coccoliths/coccolithophores are crucial for the seed/nucleation phase of crust formation (biomineralization aspect). Subsequently, after the biologically induced mineralization phase Mn-oxide deposition proceeds "auto"catalytically.

  7. Evidence for methane production by marine algae (Emiliana huxleyi) and its implication for the methane paradox in oxic waters

    NASA Astrophysics Data System (ADS)

    Lenhart, K.; Klintzsch, T.; Langer, G.; Nehrke, G.; Bunge, M.; Schnell, S.; Keppler, F.

    2015-12-01

    Methane (CH4), an important greenhouse gas that affects radiation balance and consequently the earth's climate, still has uncertainties in its sinks and sources. The world's oceans are considered to be a source of CH4 to the atmosphere, although the biogeochemical processes involved in its formation are not fully understood. Several recent studies provided strong evidence of CH4 production in oxic marine and freshwaters but its source is still a topic of debate. Studies of CH4 dynamics in surface waters of oceans and large lakes have concluded that pelagic CH4 supersaturation cannot be sustained either by lateral inputs from littoral or benthic inputs alone. However, frequently regional and temporal oversaturation of surface waters occurs. This comprises the observation of a CH4 oversaturating state within the surface mixed layer, sometimes also termed the "oceanic methane paradox". In this study we considered marine algae as a possible direct source of CH4. Therefore, the coccolithophore Emiliania huxleyi was grown under controlled laboratory conditions and supplemented with two 13C-labelled carbon substrates, namely bicarbonate and a position-specific 13C-labelled methionine (R-S-13CH3). The CH4 production was 0.7 μg POC g-1 d-1, or 30 ng g-1 POC h-1. After supplementation of the cultures with the 13C labelled substrate, the isotope label was observed in headspace-CH4. Moreover, the absence of methanogenic archaea within the algal culture and the oxic conditions during CH4 formation suggest that marine algae such as Emiliania huxleyi contribute to the observed spatial and temporal restricted CH4 oversaturation in ocean surface waters.

  8. Seismic evidence for a mantle source for mid-Proterozoic anorthosites and implications for models of crustal growth

    USGS Publications Warehouse

    Musacchio, G.; Mooney, W.D.

    2002-01-01

    Voluminous anorthosite intrusions are common in mid-Proterozoic crust. Historically, two end-member models have been proposed for the origin of these anorthosites. In the first model anorthosites derive from fractionation of a mantle source leaving a residue of metagabbro in the lower crust; in the second model anorthosites are the product of partial melting of the lower crust with residual pyroxene and high-grade minerals (i.e. a pyroxenitic and/or metapelitic lower crust). Although a general consensus has developed that the first model provides the best fit to petrological and geochemical constraints, the sparse evidence for mafic and ultramafic counterparts to the anorthosites leaves the issue still unresolved. We use the absolute P-wave velocity and the ratio between P- and S-wave velocities (VP/VS) to infer the composition of the lower crust beneath the Marcy Anorthosite (New York State, USA). Seismic refraction data reveal a lower crust 20 km thick, where VP and VP/VS range from top to bottom between 7.0 km s-1 and 7.2 ?? 0.1 and 1.84 km s-1 and 1.81 ?? 0.02, respectively. Laboratory measurements on rock samples indicate that these seismic properties are typical of plagioclase-rich rocks. Magmatic underplating of basaltic melts is a mechanism to form plagioclase-rich bulk composition for the Grenville crust. At the bottom of the lower crust, increase of P-wave velocity, slight decrease of VP/VS ratios and the presence of a low-reflective seismic Moho are additional observations supporting crust-mantle interactions related to magmatic underplating. High P-wave velocity (8.6 km s-1) in the upper mantle may indicate that the ultramafic portion (e.g. pyroxenites) of the underplated magma has become eclogite. High average P-wave velocity (6.7 km s-1) and VP/VS (1.81), and the exceptional abundance of anorthosites-norites-troctolites among the rocks exposed at the surface, indicate that the Grenville Proterozoic crust may have a unique plagioclase-rich bulk

  9. In vivo Modeling Implicates APOL1 in Nephropathy: Evidence for Dominant Negative Effects and Epistasis under Anemic Stress.

    PubMed

    Anderson, Blair R; Howell, David N; Soldano, Karen; Garrett, Melanie E; Katsanis, Nicholas; Telen, Marilyn J; Davis, Erica E; Ashley-Koch, Allison E

    2015-07-01

    African Americans have a disproportionate risk for developing nephropathy. This disparity has been attributed to coding variants (G1 and G2) in apolipoprotein L1 (APOL1); however, there is little functional evidence supporting the role of this protein in renal function. Here, we combined genetics and in vivo modeling to examine the role of apol1 in glomerular development and pronephric filtration and to test the pathogenic potential of APOL1 G1 and G2. Translational suppression or CRISPR/Cas9 genome editing of apol1 in zebrafish embryos results in podocyte loss and glomerular filtration defects. Complementation of apol1 morphants with wild-type human APOL1 mRNA rescues these defects. However, the APOL1 G1 risk allele does not ameliorate defects caused by apol1 suppression and the pathogenicity is conferred by the cis effect of both individual variants of the G1 risk haplotype (I384M/S342G). In vivo complementation studies of the G2 risk allele also indicate that the variant is deleterious to protein function. Moreover, APOL1 G2, but not G1, expression alone promotes developmental kidney defects, suggesting a possible dominant-negative effect of the altered protein. In sickle cell disease (SCD) patients, we reported previously a genetic interaction between APOL1 and MYH9. Testing this interaction in vivo by co-suppressing both transcripts yielded no additive effects. However, upon genetic or chemical induction of anemia, we observed a significantly exacerbated nephropathy phenotype. Furthermore, concordant with the genetic interaction observed in SCD patients, APOL1 G2 reduces myh9 expression in vivo, suggesting a possible interaction between the altered APOL1 and myh9. Our data indicate a critical role for APOL1 in renal function that is compromised by nephropathy-risk encoding variants. Moreover, our interaction studies indicate that the MYH9 locus is also relevant to the phenotype in a stressed microenvironment and suggest that consideration of the context

  10. [Current epidemiological evidence regarding the health effects of low-dose ionizing radiation. Implications for radiation protection, public health and forensic medicine].

    PubMed

    Manzoli, Lamberto; Romano, Ferdinando; Schioppa, Francesco; D'Ovidio, Cristian; Lodi, Vittorio; Pirone, Giovanni Maria

    2004-01-01

    The health effects of low-dose ionizing radiation have been widely studied, but remain uncertain. Up-to-date knowledge about epidemiologic evidence for potential human health effects of low dose ionizing radiation is important for revising national radiation protection legislation. This review, conducted by a multidisciplinary research team of the Italian Institute of Social Medicine, evaluates epidemiologic studies published since July 2003. After careful selection, a total of 302 studies were reviewed. Greater emphasis was given to papers that analyzed data using standardized incidence and mortality ratios and to studies regarding occupational exposures in all workers, healthcare workers and aircrew members. Nevertheless, studies regarding A-bomb survivors of Hiroshima/Nagasaki, Chernobyl cleanup workers, patients exposed for medical reasons, and workers in nuclear plants were also included. Given the limitations of epidemiological studies and excluding the cosmic rays context, which requires further research, the authors conclude that harmful effects from exposures to ionizing radiation at doses lower than 100 mSv cannot be ruled out. Nevertheless, if any harmful health effects do exist, they are certainly very small. The implications for radiation protection, public health and forensic medicine are discussed. PMID:15213763

  11. Pheromone Autodetection: Evidence and Implications

    PubMed Central

    Holdcraft, Robert; Rodriguez-Saona, Cesar; Stelinski, Lukasz L.

    2016-01-01

    Olfactory communication research with insects utilizing sex pheromones has focused on the effects of pheromones on signal receivers. Early pheromone detection studies using the silkworm moth, Bombyx mori L., and Saturniids led to the assumption that emitters, especially females, are unable to detect their own pheromone. Pheromone anosmia, i.e., the inability of females to detect their conspecific sex pheromone, was often assumed, and initially little attention was paid to female behaviors that may result from autodetection, i.e., the ability of females to detect their sex pheromone. Detection of conspecific pheromone plumes from nearby females may provide information to improve chances of mating success and progeny survival. Since the first documented example in 1972, numerous occurrences of autodetection have been observed and verified in field and laboratory studies. We summarize here a significant portion of research relating to autodetection. Electrophysiological and behavioral investigations, as well as expression patterns of proteins involved in pheromone autodetection are included. We discuss problems inherent in defining a boundary between sex and aggregation pheromones considering the occurrence of autodetection, and summarize hypothesized selection pressures favoring autodetection. Importance of including autodetection studies in future work is emphasized by complications arising from a lack of knowledge combined with expanding the use of pheromones in agriculture. PMID:27120623

  12. Pheromone Autodetection: Evidence and Implications.

    PubMed

    Holdcraft, Robert; Rodriguez-Saona, Cesar; Stelinski, Lukasz L

    2016-01-01

    Olfactory communication research with insects utilizing sex pheromones has focused on the effects of pheromones on signal receivers. Early pheromone detection studies using the silkworm moth, Bombyx mori L., and Saturniids led to the assumption that emitters, especially females, are unable to detect their own pheromone. Pheromone anosmia, i.e., the inability of females to detect their conspecific sex pheromone, was often assumed, and initially little attention was paid to female behaviors that may result from autodetection, i.e., the ability of females to detect their sex pheromone. Detection of conspecific pheromone plumes from nearby females may provide information to improve chances of mating success and progeny survival. Since the first documented example in 1972, numerous occurrences of autodetection have been observed and verified in field and laboratory studies. We summarize here a significant portion of research relating to autodetection. Electrophysiological and behavioral investigations, as well as expression patterns of proteins involved in pheromone autodetection are included. We discuss problems inherent in defining a boundary between sex and aggregation pheromones considering the occurrence of autodetection, and summarize hypothesized selection pressures favoring autodetection. Importance of including autodetection studies in future work is emphasized by complications arising from a lack of knowledge combined with expanding the use of pheromones in agriculture. PMID:27120623

  13. Evidence that the hexose-to-sucrose ratio does not control the switch to storage product accumulation in oilseeds: analysis of tobacco seed development and effects of overexpressing apoplastic invertase.

    PubMed

    Tomlinson, Kim L; McHugh, Sylvia; Labbe, Helene; Grainger, John L; James, Lisa E; Pomeroy, Keith M; Mullin, John W; Miller, Shea S; Dennis, David T; Miki, Brian L A

    2004-10-01

    Wild-type tobacco (Nicotiana tabacum L.) seed development was characterized with respect to architecture and carbohydrate metabolism. Tobacco seeds accumulate oil and protein in the embryo, cellular endosperm and inner layer of the seed coat. They have high cell wall invertase (INV) and hexoses in early development which is typical of seeds. INV and the ratio of hexose to sucrose decline during development, switching from high hex to high suc, but not until most oil and all protein accumulation has occurred. The oil synthesis which coincides with the switch is mostly within the embryo. INV activity is greater than sucrose synthase activity throughout development, and both activities exceed the demand for carbohydrate for dry matter accumulation. To investigate the role of INV-mediated suc metabolism in oilseeds, genes for yeast INV and/or hexokinase (HK) were expressed under a seed-specific napin promoter, targeting activity to the apoplast and cytosol, respectively. Manipulating the INV pathway in an oilseed could either increase oil accumulation and sink strength, or disrupt carbohydrate metabolism, possibly through sugar-sensing, and decrease the storage function. Neither effect was found: transgenics with INV and/or HK increased 30-fold and 10-fold above wild-type levels had normal seed size and composition. This contrasted with dramatic effects on sugar contents in the INV lines.

  14. Stress-induced accumulation of glycerol in the flesh fly, Sarcophaga bullata: evidence indicating anti-desiccant and cryoprotectant functions of this polyol and a role for the brain in coordinating the response.

    PubMed

    Yoder, Jay A; Benoit, Joshua B; Denlinger, David L; Rivers, David B

    2006-02-01

    Nondiapausing larvae of the flesh fly, Sarcophaga bullata, responded to several forms of short-term environmental stress (low temperature, anoxia and desiccation) by accumulating glycerol. Elevation of this polyol, regardless of the type of stress that induced accumulation, conferred cold resistance: larvae with high glycerol levels were 3-4 times more tolerant of a 2h exposure to -10 degrees C than unstressed larvae. Protection against low temperature injury, as well as dehydration, was also attained by injection of exogenous glycerol into third instar larvae. This artificially induced cold hardiness was only temporary: when glycerol-injected larvae were exposed to -10 degrees C immediately after injection, survival was high, but none survived if they were injected and then held at 25 degrees C for 2 days before the -10 degrees C exposure. Larvae ligated behind the brain immediately after low temperature exposure failed to accumulate glycerol, but glycerol did accumulate in larvae ligated 6-24h after cold treatment, thus implying a critical role for the brain in initiating glycerol production. Interestingly, a much shorter exposure (2h) to low temperature was sufficient to reduce the maximum rate of water loss. Collectively, these observations suggest that multiple pathways may be exploited in response to stress: one pathway is most likely associated with rapid cold hardening (RCH) which generates immediate protection, and a second pathway remains activated for a longer period to enhance the initial protection afforded by glycerol.

  15. Experimental evidence for kinetic effects on B/Ca in synthetic calcite: Implications for potential B(OH)4- and B(OH)3 incorporation

    NASA Astrophysics Data System (ADS)

    Uchikawa, Joji; Penman, Donald E.; Zachos, James C.; Zeebe, Richard E.

    2015-02-01

    The boron to calcium ratio (B/Ca) in biogenic CaCO3 is being increasingly utilized as a proxy for past ocean carbonate chemistry. However, B/Ca of cultured and core-top foraminifers show dependence on multiple physicochemical seawater properties and only a few of those have been inorganically tested for their impacts. Accordingly, our understanding of the controls on foraminiferal B/Ca and thus how to interpret B/Ca in fossil shells is incomplete. To gain a clearer understanding of the B incorporation mechanism, we performed inorganic calcite precipitation experiments using a pH-stat system. As previously reported, we confirm that B/Ca in calcite increases with both fluid pH and total B concentration (denoted as [BT], where [BT] = [B(OH)3] + [B(OH)4-]). We provide the first evidence that B/Ca also increases with the concentration of total dissolved inorganic carbon (DIC) and calcium ion. With the exception of the [BT] experiments, these chemical manipulations were accompanied by an increase in calcite saturation, and accordingly precipitation rate (denoted as R). But when pH and [Ca2+] were jointly varied at a fixed saturation level to maintain relatively constant R at different pH and [Ca2+] combinations, B/Ca was insensitive to both pH and [Ca2+] changes. These experimental results unequivocally suggest kinetic effects related to R on B/Ca. Furthermore, with a suite of chemical manipulations we found that the B/Ca variability is explicable by just R and the [BT]/[DIC] ratio in the parent fluids. This observation was particularly robust for relatively rapidly precipitated samples, whereas for relatively slowly precipitated samples, it was somewhat ambiguous whether the [BT]/[DIC] or [B(OH)4-]/[HCO3-] ratio provides a better fit to the experimental data. Nonetheless, our experimental results can be considered as indirect evidence for incorporation of both B(OH)4- and B(OH)3 into calcite. We propose a simple mathematical expression to describe the mode of B

  16. Psychological and social aspects of infertility in men: an overview of the evidence and implications for psychologically informed clinical care and future research.

    PubMed

    Fisher, Jane R W; Hammarberg, Karin

    2012-01-01

    Research concerning the psychosocial aspects of infertility and infertility treatment focuses more often on women than men. The aim of this review was to synthesize the English-language evidence related to the psychological and social aspects of infertility in men and discuss the implications of these reports for clinical care and future research. A structured search identified 73 studies that reported data concerning the desire for fatherhood and the psychological and social aspects of diagnosis, assisted reproductive technology (ART) treatment and unsuccessful treatment among men with fertility difficulties. The studies are diverse in conceptualisation, design, setting and data collection, but the findings were reasonably consistent. These studies indicated that fertile and infertile childless men of reproductive age have desires to experience parenthood that are similar to those of their female counterparts; in addition, diagnosis and initiation of treatment are associated with elevated infertility-specific anxiety, and unsuccessful treatment can lead to a state of lasting sadness. However, rates of clinically significant mental health problems among this patient population are no higher than in the general population. Infertile men who are socially isolated, have an avoidant coping style and appraise stressful events as overwhelming, are more vulnerable to severe anxiety than men without these characteristics. Men prefer oral to written treatment information and prefer to receive emotional support from infertility clinicians rather than from mental health professionals, self-help support groups or friends. Nevertheless, structured, facilitated psycho-educational groups that are didactic but permit informal sharing of experiences might be beneficial. There are gaps in knowledge about factors governing seeking, persisting with and deciding to cease treatment; experiences of invasive procedures; parenting after assisted conception; adoption and infertility

  17. Psychological and social aspects of infertility in men: an overview of the evidence and implications for psychologically informed clinical care and future research

    PubMed Central

    Fisher, Jane RW; Hammarberg, Karin

    2012-01-01

    Research concerning the psychosocial aspects of infertility and infertility treatment focuses more often on women than men. The aim of this review was to synthesize the English-language evidence related to the psychological and social aspects of infertility in men and discuss the implications of these reports for clinical care and future research. A structured search identified 73 studies that reported data concerning the desire for fatherhood and the psychological and social aspects of diagnosis, assisted reproductive technology (ART) treatment and unsuccessful treatment among men with fertility difficulties. The studies are diverse in conceptualisation, design, setting and data collection, but the findings were reasonably consistent. These studies indicated that fertile and infertile childless men of reproductive age have desires to experience parenthood that are similar to those of their female counterparts; in addition, diagnosis and initiation of treatment are associated with elevated infertility-specific anxiety, and unsuccessful treatment can lead to a state of lasting sadness. However, rates of clinically significant mental health problems among this patient population are no higher than in the general population. Infertile men who are socially isolated, have an avoidant coping style and appraise stressful events as overwhelming, are more vulnerable to severe anxiety than men without these characteristics. Men prefer oral to written treatment information and prefer to receive emotional support from infertility clinicians rather than from mental health professionals, self-help support groups or friends. Nevertheless, structured, facilitated psycho-educational groups that are didactic but permit informal sharing of experiences might be beneficial. There are gaps in knowledge about factors governing seeking, persisting with and deciding to cease treatment; experiences of invasive procedures; parenting after assisted conception; adoption and infertility

  18. Mitochondrial accumulation of a lipophilic cation conjugated to an ionisable group depends on membrane potential, pH gradient and pK(a): implications for the design of mitochondrial probes and therapies.

    PubMed

    Finichiu, Peter G; James, Andrew M; Larsen, Lesley; Smith, Robin A J; Murphy, Michael P

    2013-02-01

    Mitochondria play key roles in a broad range of biomedical situations, consequently there is a need to direct bioactive compounds to mitochondria as both therapies and probes. A successful approach has been to target compounds to mitochondria by conjugation to lipophilic cations, such as triphenylphosphonium (TPP), which utilize the large mitochondrial membrane potential (Δψ(m), negative inside) to drive accumulation. This has proven effective both in vitro and in vivo for a range of bioactive compounds and probes. However so far only neutral appendages have been targeted to mitochondria in this way. Many bioactive functional moieties that we would like to send to mitochondria contain ionisable groups with pK (a) in the range that creates an assortment of charged species under physiological conditions. To see if such ionisable compounds can also be taken up by mitochondria, we determined the general requirements for the accumulation within mitochondria of a TPP cation conjugated to a carboxylic acid or an amine. Both were taken up by energised mitochondria in response to the protonmotive force. A lipophilic TPP cation attached to a carboxylic acid was accumulated to a greater extent than a simple TPP cation due to the interaction of the weakly acidic group with the pH gradient (ΔpH). In contrast, a lipophilic TPP cation attached to an amine was accumulated less than the simple cation due to exclusion of the weakly basic group by the ΔpH. From these data we derived a simple equation that describes the uptake of lipophilic cations containing ionisable groups as a function of Δψ(m), ΔpH and pK(a). These findings may facilitate the rational design of additional mitochondrial targeted probes and therapies.

  19. Copper accumulation in the crayfish (Orconectes rusticus)

    SciTech Connect

    Evans, M.L.

    1980-06-01

    The purpose of this study was to determine whether or not the crayfish, O. rusticus could fulfill Nehring's (1976) criteria for a good biological monitor of heavy metal pollution. Since there is some evidence that the cupric ion is the most toxic form of aqueous copper, crayfish-accumulated copper was compared to both total and cupric copper in the culture water.

  20. Neurodegeneration with Brain Iron Accumulation

    MedlinePlus

    ... Diversity Find People About NINDS NINDS Neurodegeneration with Brain Iron Accumulation Information Page Synonym(s): Hallervorden-Spatz Disease, ... done? Clinical Trials Organizations What is Neurodegeneration with Brain Iron Accumulation? Neurodegeneration with brain iron accumulation (NBIA) ...

  1. Plastids and Carotenoid Accumulation.

    PubMed

    Li, Li; Yuan, Hui; Zeng, Yunliu; Xu, Qiang

    2016-01-01

    Plastids are ubiquitously present in plants and are the organelles for carotenoid biosynthesis and storage. Based on their morphology and function, plastids are classified into various types, i.e. proplastids, etioplasts, chloroplasts, amyloplasts, and chromoplasts. All plastids, except proplastids, can synthesize carotenoids. However, plastid types have a profound effect on carotenoid accumulation and stability. In this chapter, we discuss carotenoid biosynthesis and regulation in various plastids with a focus on carotenoids in chromoplasts. Plastid transition related to carotenoid biosynthesis and the different capacity of various plastids to sequester carotenoids and the associated effect on carotenoid stability are described in light of carotenoid accumulation in plants. PMID:27485226

  2. Plastids and Carotenoid Accumulation.

    PubMed

    Li, Li; Yuan, Hui; Zeng, Yunliu; Xu, Qiang

    2016-01-01

    Plastids are ubiquitously present in plants and are the organelles for carotenoid biosynthesis and storage. Based on their morphology and function, plastids are classified into various types, i.e. proplastids, etioplasts, chloroplasts, amyloplasts, and chromoplasts. All plastids, except proplastids, can synthesize carotenoids. However, plastid types have a profound effect on carotenoid accumulation and stability. In this chapter, we discuss carotenoid biosynthesis and regulation in various plastids with a focus on carotenoids in chromoplasts. Plastid transition related to carotenoid biosynthesis and the different capacity of various plastids to sequester carotenoids and the associated effect on carotenoid stability are described in light of carotenoid accumulation in plants.

  3. Apoptotic Debris Accumulates on Hematopoietic Cells and Promotes Disease in Murine and Human Systemic Lupus Erythematosus.

    PubMed

    Kang, SunAh; Rogers, Jennifer L; Monteith, Andrew J; Jiang, Chuancang; Schmitz, John; Clarke, Stephen H; Tarrant, Teresa K; Truong, Young K; Diaz, Marilyn; Fedoriw, Yuri; Vilen, Barbara J

    2016-05-15

    Apoptotic debris, autoantibody, and IgG-immune complexes (ICs) have long been implicated in the inflammation associated with systemic lupus erythematosus (SLE); however, it remains unclear whether they initiate immune-mediated events that promote disease. In this study, we show that PBMCs from SLE patients experiencing active disease, and hematopoietic cells from lupus-prone MRL/lpr and NZM2410 mice accumulate markedly elevated levels of surface-bound nuclear self-antigens. On dendritic cells (DCs) and macrophages (MFs), the self-antigens are part of IgG-ICs that promote FcγRI-mediated signal transduction. Accumulation of IgG-ICs is evident on ex vivo myeloid cells from MRL/lpr mice by 10 wk of age and steadily increases prior to lupus nephritis. IgG and FcγRI play a critical role in disease pathology. Passive transfer of pathogenic IgG into IgG-deficient MRL/lpr mice promotes the accumulation of IgG-ICs prior to significant B cell expansion, BAFF secretion, and lupus nephritis. In contrast, diminishing the burden IgG-ICs in MRL/lpr mice through deficiency in FcγRI markedly improves these lupus pathologies. Taken together, our findings reveal a previously unappreciated role for the cell surface accumulation of IgG-ICs in human and murine lupus. PMID:27059595

  4. Palaeopangaea in Meso-Neoproterozoic times: The palaeomagnetic evidence and implications to continental integrity, supercontinent form and Eocambrian break-up

    NASA Astrophysics Data System (ADS)

    Piper, J. D. A.

    2010-09-01

    A feature of the developing Precambrian palaeomagnetic record is the recognition that unique configurations appear to apply to large continental shields for protracted periods of time, with quasi-integrity providing a general explanation for the distinctive geological and geochemical signatures of continentality that characterise the Proterozoic Eon of Earth history (2.5-0.542 Ga). This paper evaluates the palaeomagnetic evidence for the Palaeopangaean reconstruction during the latter part of this eon. It uses a comprehensive summary of poles assigned to the interval ˜1.3-0.6 Ga to demonstrate that the records from diverse shields conform to an apparent polar wander path (APWP) comprising tracks of 100-200 Myr duration forming the limbs of tight elongate loops. These comprise the Gardar Track (˜1.3-1.14 Ga), the Keweenawan Track (˜1.14-1.04 Ga), the Grenville-Sveconorwegian Loop (˜1.14-0.85 Ga) and the Franklin-Adelaide Track (˜0.8-0.6 Ga). The latter terminates in a protracted quasi-static interval between ˜0.75 and 0.6 Ga indicating that Plate Tectonics, and an associated input from the Earth's internal heat budget, nearly ceased during the interval embracing widespread glaciation. The subsequent continental break-up was characterised by large scale release of accumulated heat from beneath the continental lid and was expressed by rapid continental movements and major crustal growth at ˜0.6 Ga. The strength of the Palaeopangaean analysis lies in the invariance of the rotational operations over such a long interval of geological history, and the geological and geophysical relevance of the reconstruction. Data from a number of disparate shields indicate that the crust was still integral in the Palaeopangaean configuration by the time of the Marinoan glaciations ˜0.6 Ga ago. After this time the APW paths explicitly scatter in the signature of continental break-up between ˜0.6 and 0.55 Ga and during this latter interval it is not yet possible to define any

  5. Accumulator with preclosing preventer

    SciTech Connect

    Murthy, R.R.; Rice, B.J.

    1981-11-24

    A guided-float accumulator suitable for use with a hydraulic system for an oil well blowout preventer is provided with a wing shut-off valve. Radially inwardly directed outlet parts are aimed at the bottom of the valve wing to generate unbalanced reaction forces which oppose the bernoulli effect forces caused by rapid movement of fluid through the chamber of the shut-off valve, thus preventing premature closing of the valve.

  6. Heat exchanger-accumulator

    DOEpatents

    Ecker, Amir L.

    1980-01-01

    What is disclosed is a heat exchanger-accumulator for vaporizing a refrigerant or the like, characterized by an upright pressure vessel having a top, bottom and side walls; an inlet conduit eccentrically and sealingly penetrating through the top; a tubular overflow chamber disposed within the vessel and sealingly connected with the bottom so as to define an annular outer volumetric chamber for receiving refrigerant; a heat transfer coil disposed in the outer volumetric chamber for vaporizing the liquid refrigerant that accumulates there; the heat transfer coil defining a passageway for circulating an externally supplied heat exchange fluid; transferring heat efficiently from the fluid; and freely allowing vaporized refrigerant to escape upwardly from the liquid refrigerant; and a refrigerant discharge conduit penetrating sealingly through the top and traversing substantially the length of the pressurized vessel downwardly and upwardly such that its inlet is near the top of the pressurized vessel so as to provide a means for transporting refrigerant vapor from the vessel. The refrigerant discharge conduit has metering orifices, or passageways, penetrating laterally through its walls near the bottom, communicating respectively interiorly and exteriorly of the overflow chamber for controllably carrying small amounts of liquid refrigerant and oil to the effluent stream of refrigerant gas.

  7. Neurodegeneration with brain iron accumulation: update on pathogenic mechanisms

    PubMed Central

    Levi, Sonia; Finazzi, Dario

    2014-01-01

    Perturbation of iron distribution is observed in many neurodegenerative disorders, including Alzheimer’s and Parkinson’s disease, but the comprehension of the metal role in the development and progression of such disorders is still very limited. The combination of more powerful brain imaging techniques and faster genomic DNA sequencing procedures has allowed the description of a set of genetic disorders characterized by a constant and often early accumulation of iron in specific brain regions and the identification of the associated genes; these disorders are now collectively included in the category of neurodegeneration with brain iron accumulation (NBIA). So far 10 different genetic forms have been described but this number is likely to increase in short time. Two forms are linked to mutations in genes directly involved in iron metabolism: neuroferritinopathy, associated to mutations in the FTL gene and aceruloplasminemia, where the ceruloplasmin gene product is defective. In the other forms the connection with iron metabolism is not evident at all and the genetic data let infer the involvement of other pathways: Pank2, Pla2G6, C19orf12, COASY, and FA2H genes seem to be related to lipid metabolism and to mitochondria functioning, WDR45 and ATP13A2 genes are implicated in lysosomal and autophagosome activity, while the C2orf37 gene encodes a nucleolar protein of unknown function. There is much hope in the scientific community that the study of the NBIA forms may provide important insight as to the link between brain iron metabolism and neurodegenerative mechanisms and eventually pave the way for new therapeutic avenues also for the more common neurodegenerative disorders. In this work, we will review the most recent findings in the molecular mechanisms underlining the most common forms of NBIA and analyze their possible link with brain iron metabolism. PMID:24847269

  8. Informatics, evidence-based care, and research; implications for national policy: a report of an American Medical Informatics Association health policy conference.

    PubMed

    Bloomrosen, Meryl; Detmer, Don E

    2010-01-01

    There is an increased level of activity in the biomedical and health informatics world (e-prescribing, electronic health records, personal health records) that, in the near future, will yield a wealth of available data that we can exploit meaningfully to strengthen knowledge building and evidence creation, and ultimately improve clinical and preventive care. The American Medical Informatics Association (AMIA) 2008 Health Policy Conference was convened to focus and propel discussions about informatics-enabled evidence-based care, clinical research, and knowledge management. Conference participants explored the potential of informatics tools and technologies to improve the evidence base on which providers and patients can draw to diagnose and treat health problems. The paper presents a model of an evidence continuum that is dynamic, collaborative, and powered by health informatics technologies. The conference's findings are described, and recommendations on terminology harmonization, facilitation of the evidence continuum in a "wired" world, development and dissemination of clinical practice guidelines and other knowledge support strategies, and the role of diverse stakeholders in the generation and adoption of evidence are presented.

  9. Type-1 Collagen differentially alters β-catenin accumulation in primary Dupuytren's Disease cord and adjacent palmar fascia cells

    PubMed Central

    Vi, Linda; Njarlangattil, Anna; Wu, Yan; Gan, Bing Siang; O'Gorman, David B

    2009-01-01

    Background Dupuytren's Disease (DD) is a debilitating contractile fibrosis of the palmar fascia characterised by excess collagen deposition, contractile myofibroblast development, increased Transforming Growth Factor-β levels and β-catenin accumulation. The aim of this study was to determine if a collagen-enriched environment, similar to in vivo conditions, altered β-catenin accumulation by primary DD cells in the presence or absence of Transforming Growth Factor-β. Methods Primary DD and patient matched, phenotypically normal palmar fascia (PF) cells were cultured in the presence or absence of type-1 collagen and Transforming Growth Factor-β1. β-catenin and α-smooth muscle actin levels were assessed by western immunoblotting and immunofluorescence microscopy. Results DD cells display a rapid depletion of cellular β-catenin not evident in patient-matched PF cells. This effect was not evident in either cell type when cultured in the absence of type-1 collagen. Exogenous addition of Transforming Growth Factor-β1 to DD cells in collagen culture negates the loss of β-catenin accumulation. Transforming Growth Factor-β1-induced α-smooth muscle actin, a marker of myofibroblast differentiation, is attenuated by the inclusion of type-1 collagen in cultures of DD and PF cells. Conclusion Our findings implicate type-1 collagen as a previously unrecognized regulator of β-catenin accumulation and a modifier of TGF-β1 signaling specifically in primary DD cells. These data have implications for current treatment modalities as well as the design of in vitro models for research into the molecular mechanisms of DD. PMID:19545383

  10. Solids Accumulation Scouting Studies

    SciTech Connect

    Duignan, M. R.; Steeper, T. J.; Steimke, J. L.

    2012-09-26

    The objective of Solids Accumulation activities was to perform scaled testing to understand the behavior of remaining solids in a Double Shell Tank (DST), specifically AW-105, at Hanford during multiple fill, mix, and transfer operations. It is important to know if fissionable materials can concentrate when waste is transferred from staging tanks prior to feeding waste treatment plants. Specifically, there is a concern that large, dense particles containing plutonium could accumulate in poorly mixed regions of a blend tank heel for tanks that employ mixing jet pumps. At the request of the DOE Hanford Tank Operations Contractor, Washington River Protection Solutions, the Engineering Development Laboratory of the Savannah River National Laboratory performed a scouting study in a 1/22-scale model of a waste staging tank to investigate this concern and to develop measurement techniques that could be applied in a more extensive study at a larger scale. Simulated waste tank solids: Gibbsite, Zirconia, Sand, and Stainless Steel, with stainless steel particles representing the heavier particles, e.g., plutonium, and supernatant were charged to the test tank and rotating liquid jets were used to mix most of the solids while the simulant was pumped out. Subsequently, the volume and shape of the mounds of residual solids and the spatial concentration profiles for the surrogate for heavier particles were measured. Several techniques were developed and equipment designed to accomplish the measurements needed and they included: 1. Magnetic particle separator to remove simulant stainless steel solids. A device was designed and built to capture these solids, which represent the heavier solids during a waste transfer from a staging tank. 2. Photographic equipment to determine the volume of the solids mounds. The mounds were photographed as they were exposed at different tank waste levels to develop a composite of topographical areas. 3. Laser rangefinders to determine the volume of

  11. Calcite-accumulating large sulfur bacteria of the genus Achromatium in Sippewissett Salt Marsh.

    PubMed

    Salman, Verena; Yang, Tingting; Berben, Tom; Klein, Frieder; Angert, Esther; Teske, Andreas

    2015-11-01

    Large sulfur bacteria of the genus Achromatium are exceptional among Bacteria and Archaea as they can accumulate high amounts of internal calcite. Although known for more than 100 years, they remain uncultured, and only freshwater populations have been studied so far. Here we investigate a marine population of calcite-accumulating bacteria that is primarily found at the sediment surface of tide pools in a salt marsh, where high sulfide concentrations meet oversaturated oxygen concentrations during the day. Dynamic sulfur cycling by phototrophic sulfide-oxidizing and heterotrophic sulfate-reducing bacteria co-occurring in these sediments creates a highly sulfidic environment that we propose induces behavioral differences in the Achromatium population compared with reported migration patterns in a low-sulfide environment. Fluctuating intracellular calcium/sulfur ratios at different depths and times of day indicate a biochemical reaction of the salt marsh Achromatium to diurnal changes in sedimentary redox conditions. We correlate this calcite dynamic with new evidence regarding its formation/mobilization and suggest general implications as well as a possible biological function of calcite accumulation in large bacteria in the sediment environment that is governed by gradients. Finally, we propose a new taxonomic classification of the salt marsh Achromatium based on their adaptation to a significantly different habitat than their freshwater relatives, as indicated by their differential behavior as well as phylogenetic distance on 16S ribosomal RNA gene level. In future studies, whole-genome characterization and additional ecophysiological factors could further support the distinctive position of salt marsh Achromatium.

  12. Study of fluxes at low concentrations of l-tri-iodothyronine with rat liver cells and their plasma-membrane vesicles. Evidence for the accumulation of the hormone against a gradient

    PubMed Central

    Rao, Govind S.; Rao, Marie Luise; Thilmann, Astrid; Quednau, Hans D.

    1981-01-01

    1. Influx and efflux of l-tri-[125I]iodothyronine with isolated rat liver parenchymal cells and their plasma-membrane vesicles were studied by a rapid centrifugation technique. 2. At 23°C and in the concentration range that included the concentration of free l-tri-iodothyronine in rat plasma (3–5pm) influx into cells was saturable; an apparent Kt value of 8.6±1.6pm was obtained. 3. At 5pm-l-tri-[125I]iodothyronine in the external medium the ratios of the concentrations inside to outside in cells and plasma-membrane vesicles were 38:1 and 366:1 respectively after 7s of incubation. At equilibrium (60s at 23°C) uptake of l-tri-[125I]iodothyronine by cells was linear with the hormone concentration, whereas that by plasma-membrane vesicles exhibited an apparent saturation with a Kd value of 6.1±1.3pm. 4. Efflux of l-tri-[125I]iodothyronine from cells equilibrated with the hormone (5–123pm) was constant up to 21 s; the amount that flowed out was 17.7±3.8% when cells were equilibrated with 5pm-hormone. When plasma-membrane vesicles were equilibrated with l-tri-[125I]iodothyronine (556–1226pm) 66.8±5.8% flowed out after 21 s. 5. From a consideration of the data on efflux from cells and binding of l-tri-[125I]iodothyronine to the liver homogenate, as studied by the charcoal-adsorption and equilibrium-dialysis methods, it appears that 18–22% of the hormone exists in the free form in the cell. 6. Vinblastine and colchicine diminished the uptake of l-tri-[125I]iodothyronine by cells but not by plasma-membrane vesicles; binding to the cytosol fraction was not affected. Phenylbutazone, 6-n-propyl-2-thiouracil, methimazole and corticosterone diminished the uptake by cells, plasma-membrane vesicles and binding to the cytosol fraction to different extents. 7. These results suggest that at low concentrations of l-tri-[125I]iodothyronine rat liver cells and their plasma-membrane vesicles accumulated the hormone against an apparent gradient by a membrane-mediated process

  13. Role of the Microbiota in Colorectal Cancer: Updates on Microbial Associations and Therapeutic Implications

    PubMed Central

    Coleman, Olivia I.; Nunes, Tiago

    2016-01-01

    Abstract Genetic, environmental, and dietary factors have been found to influence the development and progression of colorectal cancer (CRC). More recently, accumulating evidence associates the intestinal microbiota with the initiation and progression of this disease. While studies have shown that individuals with CRC display alterations in gut bacterial composition, it remains somewhat unclear whether such differences drive cancer development or whether they are a response to tumorigenesis. In this review, the authors assess new evidence linking the community structure or specific bacterial factors of the intestinal microbiota to CRC development and progression, with insights into therapeutic implications. PMID:27790385

  14. A reassessment of the evidence for hydrothermal activity in the Neogene-Quaternary lacustrine environments of the Baza basin (Betic Cordillera, SE Spain) and its paleoecological implications

    NASA Astrophysics Data System (ADS)

    García-Aguilar, José Manuel; Guerra-Merchán, Antonio; Serrano, Francisco; Flores-Moya, Antonio; Delgado-Huertas, Antonio; Espigares, M. Patrocinio; Ros-Montoya, Sergio; Martínez-Navarro, Bienvenido; Palmqvist, Paul

    2015-03-01

    In a recent paper, García-Aguilar et al. (2014) reported on lithological, mineralogical and geochemical evidence of intense, tectonically-induced hydrothermal activity during the continental sedimentary infilling of the Baza basin, a postorogenic, intramontane area developed on the boundary between the Internal and External Zones of the Betic Cordillera, Southeast Spain (Fig. 1). This evidence includes the finding of sulfur contents, magnesium clays, fluorspar and celestine deposits, thermogene stromatolites and travertine growths in the latest Miocene (Turolian) to Middle Pleistocene lacustrine sediments and is particularly concentrated at certain stages and places (e.g. at Calabrian times in the Orce area).

  15. Sugar Accumulation in Sugarcane

    PubMed Central

    Gayler, K. R.; Glasziou, K. T.

    1972-01-01

    The rate-limiting reaction for glucose uptake in storage tissue of sugarcane, Saccharum officinarum L., appears to be the movement of glucose across the boundary between the free space and the metabolic compartments. The mechanism for uptake of glucose across this boundary has been studied using 3-O-methyl glucose, an analogue of glucose which is not metabolized by sugar-cane tissue. This analogue is taken up by sugarcane storage tissue at a similar rate to glucose. Its rate of uptake follows Michaelis-Menten kinetics, Km = 1.9 mm, and it is competitively inhibited by glucose, Ki = 2 to 3 mm. Glucose uptake is similarly inhibited by 3-O-methyl glucose. Uptake of 3-O-methyl glucose is energy-dependent and does not appear to be the result of counterflow of glucose. It is concluded that glucose and 3-O-methyl glucose uptake across the boundary between the free space and the metabolic compartment in this tissue is mediated by an energy-dependent carrier system capable of accumulating the sugars against a concentration gradient. PMID:16658002

  16. Origins of task-specific sensory-independent organization in the visual and auditory brain: neuroscience evidence, open questions and clinical implications.

    PubMed

    Heimler, Benedetta; Striem-Amit, Ella; Amedi, Amir

    2015-12-01

    Evidence of task-specific sensory-independent (TSSI) plasticity from blind and deaf populations has led to a better understanding of brain organization. However, the principles determining the origins of this plasticity remain unclear. We review recent data suggesting that a combination of the connectivity bias and sensitivity to task-distinctive features might account for TSSI plasticity in the sensory cortices as a whole, from the higher-order occipital/temporal cortices to the primary sensory cortices. We discuss current theories and evidence, open questions and related predictions. Finally, given the rapid progress in visual and auditory restoration techniques, we address the crucial need to develop effective rehabilitation approaches for sensory recovery.

  17. Origins of task-specific sensory-independent organization in the visual and auditory brain: neuroscience evidence, open questions and clinical implications.

    PubMed

    Heimler, Benedetta; Striem-Amit, Ella; Amedi, Amir

    2015-12-01

    Evidence of task-specific sensory-independent (TSSI) plasticity from blind and deaf populations has led to a better understanding of brain organization. However, the principles determining the origins of this plasticity remain unclear. We review recent data suggesting that a combination of the connectivity bias and sensitivity to task-distinctive features might account for TSSI plasticity in the sensory cortices as a whole, from the higher-order occipital/temporal cortices to the primary sensory cortices. We discuss current theories and evidence, open questions and related predictions. Finally, given the rapid progress in visual and auditory restoration techniques, we address the crucial need to develop effective rehabilitation approaches for sensory recovery. PMID:26469211

  18. Erratum: Coherent Anti-Stokes Raman Spectroscopy of Highly Compressed Solid Deuterium at 300K: Evidence for a New Phase and Implication for the Band Gap

    SciTech Connect

    Baer, B J; Evans, W J; Yoo, C

    2009-03-02

    In our original Letter, we were inconsistent in our application of the deuterium equation of state (EOS). In this Erratum we recalculated the EOS to the parameters from Hemley et al. [Phys. Rev. B 42, 6458 (1990)]. The consequence of this change is minimal. The scale of the difference is smaller, but the evidence for phase I' remains. The corrected Fig. 3 graphs are provided.

  19. It Ain't the Heat, It's the Humanity: Evidence and Implications of a Knowledge-Based Consensus on Man-Made Global Warming

    NASA Astrophysics Data System (ADS)

    Jacobs, P.; Cook, J.; Nuccitelli, D. A.

    2013-12-01

    One of the most worrisome misconceptions among the general public about climate change is a belief that scientists disagree not only about the cause of the present climate change, but also whether or not the planet is currently warming. Recent surveys have demonstrated that an overwhelming consensus exists, both within the scientific literature and among scientists with climate expertise, that the planet is warming and humans are driving this climatic change. This disconnect, or 'consensus gap', between scientific agreement and public belief has significant consequences for public understanding of the reality and cause of climate change, as well as support for potential solutions. Ensuring that the consensus message is not simply broadcast but is also accepted as legitimate by the public appears to be a primary education and communications opportunity. While the existence of a consensus is not itself evidence of a position's truth, according to Miller (2013) scientific consensus can be taken as evidence that a position is true if it is 'knowledge-based', satisfying the conditions of social calibration, apparent consilience of evidence, and social diversity. We demonstrate that the scientific consensus on anthropogenic climate change is knowledge-based, satisfying Miller's criteria. In so doing, we hope to increase confidence in its use as an education and communications tool, and assure the public of its validity. We show the consensus is socially calibrated, based on common evidential standards, ontological schemes, and shared formalism. We establish that consilience of evidence points overwhelmingly to the reality of anthropogenic climate change by examining the evidence from several perspectives. We identify unique fingerprints expected as a result of increased greenhouse forcing, eliminate potential natural drivers of climate change as the cause of the present change, and demonstrate the consistency of the observed climate response with known changes in natural

  20. Role of taurine accumulation in keratinocyte hydration.

    PubMed

    Janeke, Guido; Siefken, Wilfried; Carstensen, Stefanie; Springmann, Gunja; Bleck, Oliver; Steinhart, Hans; Höger, Peter; Wittern, Klaus-Peter; Wenck, Horst; Stäb, Franz; Sauermann, Gerhard; Schreiner, Volker; Doering, Thomas

    2003-08-01

    Epidermal keratinocytes are exposed to a low water concentration at the stratum corneum-stratum granulosum interface. When epithelial tissues are osmotically perturbed, cellular protection and cell volume regulation is mediated by accumulation of organic osmolytes such as taurine. Previous studies reported the presence of taurine in the epidermis of several animal species. Therefore, we analyzed human skin for the presence of the taurine transporter (TAUT) and studied the accumulation of taurine as one potential mechanism protecting epidermal keratinocytes from dehydration. According to our results, TAUT is expressed as a 69 kDa protein in human epidermis but not in the dermis. For the epidermis a gradient was evident with maximal levels of TAUT in the outermost granular keratinocyte layer and lower levels in the stratum spinosum. No TAUT was found in the basal layer or in the stratum corneum. Keratinocyte accumulation of taurine was induced by experimental induction of skin dryness via application of silica gel to human skin. Cultured human keratinocytes accumulated taurine in a concentration- and osmolarity-dependent manner. TAUT mRNA levels were increased after exposure of human keratinocytes to hyperosmotic culture medium, indicating osmosensitive TAUT mRNA expression as part of the adaptation of keratinocytes to hyperosmotic stress. Keratinocyte uptake of taurine was inhibited by beta-alanine but not by other osmolytes such as betaine, inositol, or sorbitol. Accumulation of taurine protected cultured human keratinocytes from both osmotically induced and ultraviolet-induced apoptosis. Our data indicate that taurine is an important epidermal osmolyte required to maintain keratinocyte hydration in a dry environment. PMID:12880428

  1. In vivo evidence of mitochondrial dysfunction and altered redox homeostasis in a genetic mouse model of propionic acidemia: Implications for the pathophysiology of this disorder.

    PubMed

    Gallego-Villar, L; Rivera-Barahona, A; Cuevas-Martín, C; Guenzel, A; Pérez, B; Barry, M A; Murphy, M P; Logan, A; Gonzalez-Quintana, A; Martín, M A; Medina, S; Gil-Izquierdo, A; Cuezva, J M; Richard, E; Desviat, L R

    2016-07-01

    Accumulation of toxic metabolites has been described to inhibit mitochondrial enzymes, thereby inducing oxidative stress in propionic acidemia (PA), an autosomal recessive metabolic disorder caused by the deficiency of mitochondrial propionyl-CoA carboxylase. PA patients exhibit neurological deficits and multiorgan complications including cardiomyopathy. To investigate the role of mitochondrial dysfunction in the development of these alterations we have used a hypomorphic mouse model of PA that mimics the biochemical and clinical hallmarks of the disease. We have studied the tissue-specific bioenergetic signature by Reverse Phase Protein Microarrays and analysed OXPHOS complex activities, mtDNA copy number, oxidative damage, superoxide anion and hydrogen peroxide levels. The results show decreased levels and/or activity of several OXPHOS complexes in different tissues of PA mice. An increase in mitochondrial mass and OXPHOS complexes was observed in brain, possibly reflecting a compensatory mechanism including metabolic reprogramming. mtDNA depletion was present in most tissues analysed. Antioxidant enzymes were also found altered. Lipid peroxidation was present along with an increase in hydrogen peroxide and superoxide anion production. These data support the hypothesis that oxidative damage may contribute to the pathophysiology of PA, opening new avenues in the identification of therapeutic targets and paving the way for in vivo evaluation of compounds targeting mitochondrial biogenesis or reactive oxygen species production. PMID:27083476

  2. Noise Reduction by Signal Accumulation

    ERIC Educational Resources Information Center

    Kraftmakher, Yaakov

    2006-01-01

    The aim of this paper is to show how the noise reduction by signal accumulation can be accomplished with a data acquisition system. This topic can be used for student projects. In many cases, the noise reduction is an unavoidable part of experimentation. Several techniques are known for this purpose, and among them the signal accumulation is the…

  3. The phenology of Rubus fruticosus in Ireland: herbarium specimens provide evidence for the response of phenophases to temperature, with implications for climate warming

    NASA Astrophysics Data System (ADS)

    Diskin, E.; Proctor, H.; Jebb, M.; Sparks, T.; Donnelly, A.

    2012-11-01

    To date, phenological research has provided evidence that climate warming is impacting both animals and plants, evidenced by the altered timing of phenophases. Much of the evidence supporting these findings has been provided by analysis of historic records and present-day fieldwork; herbaria have been identified recently as an alternative source of phenological data. Here, we used Rubus specimens to evaluate herbaria as potential sources of phenological data for use in climate change research and to develop the methodology for using herbaria specimens in phenological studies. Data relevant to phenology (collection date) were recorded from the information cards of over 600 herbarium specimens at Ireland's National Herbarium in Dublin. Each specimen was assigned a score (0-5) corresponding to its phenophase. Temperature data for the study period (1852 - 2007) were obtained from the University of East Anglia's Climate Research Unit (CRU); relationships between temperature and the dates of first flower, full flower, first fruit and full fruit were assessed using weighted linear regression. Of the five species of Rubus examined in this study, specimens of only one ( R. fruticosus) were sufficiently abundant to yield statistically significant relationships with temperature. The results revealed a trend towards earlier dates of first flower, full flower and first fruit phenophases with increasing temperature. Through its multi-phenophase approach, this research serves to extend the most recent work—which validated the use of herbaria through use of a single phenophase—to confirm herbarium-based research as a robust methodology for use in future phenological studies.

  4. Isotopic evidence bearing on Late Triassic extinction events, Queen Charlotte Islands, British Columbia, and implications for the duration and cause of the Triassic/Jurassic mass extinction

    USGS Publications Warehouse

    Ward, P.D.; Garrison, G.H.; Haggart, J.W.; Kring, D.A.; Beattie, M.J.

    2004-01-01

    Stable isotope analyses of Late Triassic to earliest Jurassic strata from Kennecott Point in the Queen Charlotte Islands, British Columbia, Canada shows the presence of two distinct and different organic carbon isotope anomalies at the Norian/Rhaetian and Rhaetian/Hettangian (=Triassic/Jurassic) stage boundaries. At the older of these boundaries, which is marked by the disappearance of the bivalve Monotis, the isotope record shows a series of short-lived positive excursions toward heavier values. Strata approaching this boundary show evidence of increasing anoxia. At the higher boundary, marked by the disappearance of the last remaining Triassic ammonites and over 50 species of radiolarians, the isotopic pattern consists of a series of short duration negative anomalies. The two events, separated by the duration of the Rhaetian age, comprise the end-Triassic mass extinction. While there is no definitive evidence as to cause, the isotopic record does not appear similar to that of the impact-caused Cretaceous/Tertiary boundary extinction. ?? 2004 Published by Elsevier B.V.

  5. Implications for early hydrothermal environments on Mars through the spectral evidence for carbonation and chloritization reactions in the Nili Fossae region

    NASA Astrophysics Data System (ADS)

    Viviano, Christina E.; Moersch, Jeffrey E.; McSween, Harry Y.

    2013-09-01

    identification of serpentine and magnesium carbonate in the eastern Nili Fossae region of Mars indicates hydrothermal alteration of an olivine-rich protolith. Here we characterize Fe/Mg phyllosilicates associated with these units and present spectral evidence for the presence of a talc component, distinguishable from saponite. Locations with magnesium carbonate are exclusively associated with talc-related phyllosilicates. In the westernmost portions of the Nili Fossae region, where a mafic protolith dominates, Fe/Mg phyllosilicates display spectral evidence for a wide degree of chloritization. We propose that Noachian Fe/Mg smectites were uniformly buried by Hesperian lava flows that initiated hydrothermal alteration in the eastern Nili Fossae region. The chloritization of smectites may have produced silica-rich fluids necessary for the serpentinization of olivine; temperature and depth constraints indicated by their distribution also suggest a hydrothermal system was present. The subsequent carbonation of serpentine and/or olivine in eastern Nili Fossae, while requiring an additional CO2 source, provides an explanation for the limited occurrence of serpentine and the colocation of carbonate and talc-bearing material throughout this area. The consequence of the hypothesized carbonation reaction and the presence of serpentine provides geochemical constraints for the proportion of CO2 present in the fluids that interacted with the protolith. If this carbonation reaction was a widespread phenomenon, it may have been an important process in the ancient Martian carbon cycle and could have provided a sink for CO2 in the past.

  6. Late stage Imbrium volcanism on the Moon: Evidence for two source regions and implications for the thermal history of Mare Imbrium

    NASA Astrophysics Data System (ADS)

    Zhang, F.; Zhu, M.-H.; Zou, Y. L.

    2016-07-01

    Large open fissures or volcanic rifts can form in volcanic terrain and they are also conduits for magma ascending through the lunar crust. On the Moon, we investigated two volcanic source regions within Mare Imbrium by tracking surface morphologic features and compositional information. The Euler source region is situated at the southwest edge of the basin, while the Lambert source region lies off the south margin of the Imbrium mascon. Survey of dike surface manifestations in Euler source site suggest that dikes are the possible source of the local upper basaltic flows and the last lava phases with well developed scarps near the Euler crater, which extend northeast to the basin center. The Euler dike swarm are radial to the basin and reveal possible dike-to-conduit transition mechanism. They reveal radial subsurface fractures which may be tensional cracks preceding to the emplacement of the last stage of the mare fill. Of these, the largest dike has a more than 100 km length. The spatial arrangement of tectonic and volcanic features in Lambert source site is directly or indirectly controlled by the regional compression and extension stresses associated with flexure in response to mascon and basalt loading. In addition, compositional variation trends show a general southwest-to-northeast flooding direction of the exposed high-Ti basalts. This will have important implications for both the Imbrium basin's mare volcanism and for the thermal evolution of Mare Imbrium and the Moon.

  7. WHO indoor air quality guidelines on household fuel combustion: Strategy implications of new evidence on interventions and exposure-risk functions

    NASA Astrophysics Data System (ADS)

    Bruce, Nigel; Pope, Dan; Rehfuess, Eva; Balakrishnan, Kalpana; Adair-Rohani, Heather; Dora, Carlos

    2015-04-01

    Background: 2.8 billion people use solid fuels as their primary cooking fuel; the resulting high levels of household air pollution (HAP) were estimated to cause more than 4 million premature deaths in 2012. The people most affected are among the world's poorest, and past experience has shown that securing adoption and sustained use of effective, low-emission stove technologies and fuels in such populations is not easy. Among the questions raised by these challenges are (i) to what levels does HAP exposure need to be reduced in order to ensure that substantial health benefits are achieved, and (ii) what intervention technologies and fuels can achieve the required levels of HAP in practice? New WHO air quality guidelines are being developed to address these issues. Aims: To address the above questions drawing on evidence from new evidence reviews conducted for the WHO guidelines. Methods: Discussion of key findings from reviews covering (i) systematic reviews of health risks from HAP exposure, (ii) newly developed exposure-response functions which combine combustion pollution risk evidence from ambient air pollution, second-hand smoke, HAP and active smoking, and (iii) a systematic review of the impacts of solid fuel and clean fuel interventions on kitchen levels of, and personal exposure to, PM2.5 and carbon monoxide (CO). Findings: Evidence on health risks from HAP suggest that controlling this exposure could reduce the risk of multiple child and adult health outcomes by 20-50%. The new integrated exposure-response functions (IERs) indicate that in order to secure these benefits, HAP levels require to be reduced to the WHO IT-1 annual average level (35 μg/m3 PM2.5), or below. The second review found that, in practice, solid fuel 'improved stoves' led to large percentage and absolute reductions, but post-intervention kitchen levels were still very high, at several hundreds of μg/m3 of PM2.5, although most solid fuel stove types met the WHO 24-hr average guideline

  8. Flavonoid accumulation patterns of transparent testa mutants of arabidopsis

    NASA Technical Reports Server (NTRS)

    Peer, W. A.; Brown, D. E.; Tague, B. W.; Muday, G. K.; Taiz, L.; Murphy, A. S.

    2001-01-01

    Flavonoids have been implicated in the regulation of auxin movements in Arabidopsis. To understand when and where flavonoids may be acting to control auxin movement, the flavonoid accumulation pattern was examined in young seedlings and mature tissues of wild-type Arabidopsis. Using a variety of biochemical and visualization techniques, flavonoid accumulation in mature plants was localized in cauline leaves, pollen, stigmata, and floral primordia, and in the stems of young, actively growing inflorescences. In young Landsberg erecta seedlings, aglycone flavonols accumulated developmentally in three regions, the cotyledonary node, the hypocotyl-root transition zone, and the root tip. Aglycone flavonols accumulated at the hypocotyl-root transition zone in a developmental and tissue-specific manner with kaempferol in the epidermis and quercetin in the cortex. Quercetin localized subcellularly in the nuclear region, plasma membrane, and endomembrane system, whereas kaempferol localized in the nuclear region and plasma membrane. The flavonoid accumulation pattern was also examined in transparent testa mutants blocked at different steps in the flavonoid biosynthesis pathway. The transparent testa mutants were shown to have precursor accumulation patterns similar to those of end product flavonoids in wild-type Landsberg erecta, suggesting that synthesis and end product accumulation occur in the same cells.

  9. Flavonoid Accumulation Patterns of Transparent Testa Mutants of Arabidopsis1

    PubMed Central

    Peer, Wendy Ann; Brown, Dana E.; Tague, Brian W.; Muday, Gloria K.; Taiz, Lincoln; Murphy, Angus S.

    2001-01-01

    Flavonoids have been implicated in the regulation of auxin movements in Arabidopsis. To understand when and where flavonoids may be acting to control auxin movement, the flavonoid accumulation pattern was examined in young seedlings and mature tissues of wild-type Arabidopsis. Using a variety of biochemical and visualization techniques, flavonoid accumulation in mature plants was localized in cauline leaves, pollen, stigmata, and floral primordia, and in the stems of young, actively growing inflorescences. In young Landsberg erecta seedlings, aglycone flavonols accumulated developmentally in three regions, the cotyledonary node, the hypocotyl-root transition zone, and the root tip. Aglycone flavonols accumulated at the hypocotyl-root transition zone in a developmental and tissue-specific manner with kaempferol in the epidermis and quercetin in the cortex. Quercetin localized subcellularly in the nuclear region, plasma membrane, and endomembrane system, whereas kaempferol localized in the nuclear region and plasma membrane. The flavonoid accumulation pattern was also examined in transparent testa mutants blocked at different steps in the flavonoid biosynthesis pathway. The transparent testa mutants were shown to have precursor accumulation patterns similar to those of end product flavonoids in wild-type Landsberg erecta, suggesting that synthesis and end product accumulation occur in the same cells. PMID:11402185

  10. Evidence implicating the 5' untranslated region of Listeria monocytogenes actA in the regulation of bacterial actin-based motility.

    PubMed

    Wong, Kendy K Y; Bouwer, H G Archie; Freitag, Nancy E

    2004-02-01

    The ActA protein of Listeria monocytogenes is a major virulence factor, essential for the recruitment and polymerization of host actin filaments that lead to intracellular motility and cell-to-cell spread of bacteria within the infected host. The expression of actA is tightly regulated and is strongly induced only when L. monocytogenes is within the host cytosol. Intracellular induction of actA expression is mediated through a single promoter element that directs the expression of a messenger RNA with a long (150 bp) 5' untranslated region (UTR). Deletion of the actA+3 to +130 upstream region was found to result in bacterial mutants that were no longer capable of intracellular actin recruitment or cell-to-cell spread, thus indicating that this region is important for actA expression. L. monocytogenes strains that contained smaller deletions (21-23 bp) within the actA upstream region demonstrated a range of actA expression levels that coincided with the amount of bacterial cell-to-cell spread observed within infected monolayers. A correlation appeared to exist between levels of actA expression and the ability of L. monocytogenes to transition from uniform actin accumulation surrounding individual bacteria (actin clouds) to directional assembly and the formation of actin tails. Bacterial mutants containing deletions that most significantly altered the predicted secondary structure of the actA mRNA 5' UTR had the largest reductions in actA expression. These results suggest that the actA 5' UTR is required for maximal ActA synthesis and that a threshold level of ActA synthesis must be achieved to promote the transition from bacteria-associated actin clouds to directional actin assembly and movement.

  11. Sedimentary record and climatic implications of recurrent deformation in the Tian Shan: Evidence from Mesozoic strata of the north Tarim, south Junggar, and Turpan basins, northwest China

    SciTech Connect

    Hendrix, M.S.; Graham, S.A.; Sobel, E.R.

    1992-01-01

    Detailed stratigraphic, sedimentologic, paleocurrent, and subsidence analyses were conducted on Mesozoic nonmarine sedimentary sections of the south Junggar, north Tarim, and Turpan basins, Xinjang Uygur Autonomous Region, northwest China. These three basins have been foreland basins throughout the Mesozoic and Cenozoic eras, as demonstrated by asymmetrically distributed basinwide sediment accumulations, foreland-style subsidence profiles, and a variety of outcrop and subsurface facies data. Mesozoic paleocurrent indicators measured in the south Junggar and north Tarim basins, as well as Mesozoic sandstone compositions from both basins, indicate that the intervening Tian Shan has existed as a positive physiographic feature partitioning the two basins throughout Mesozoic and Cenozoic time. Paleocurrent, facies, and subsurface isopach data suggest that the Turpan basin was established as a discrete feature by the Early Jurassic period. The timing and style of depositional systems within the north Tarim Mesozoic depocenter, the south Junggar Mesozoic depocenter, and the central Turpan basin are remarkably similar. Upper Triassic strata of each basin consist of alluvial conglomerate and associated braided-fluvial sandstone and siltstone which fine upward into lower through Middle Jurassic, locally organic-rich, meandering-fluvial, and lacustrine strata. Upper Jurassic braided-fluvial red beds in each basin are overlain by a distinct pulse of uppermost Jurassic alluvial conglomerate. Lower Cretaceous exposures consist of fine-grained red beds in north Tarim and Turpan and interbedded red and gray shale with local silty carbonates in south Junggar. Upper Cretaceous strata of the north Tarim and south Junggar basins are composed of alluvial conglomerate with associated braided-fluvial sandstone and siltstone. 94 refs., 17 figs.

  12. Accumulating evidence for nonstandard leptonic decays of Ds mesons.

    PubMed

    Dobrescu, Bogdan A; Kronfeld, Andreas S

    2008-06-20

    The measured rate for D{s}{+}-->l+nu decays, where l is a muon or tau, is larger than the standard model prediction, which relies on lattice QCD, at the 3.8sigma level. We discuss how robust the theoretical prediction is, and we show that the discrepancy with experiment may be explained by a charged Higgs boson or a leptoquark.

  13. Glacial landforms on German Bank, Scotian Shelf: evidence for Late Wisconsinan ice-sheet dynamics and implications for the formation of De Geer moraines

    USGS Publications Warehouse

    Todd, Brian J.; Valentine, Page C.; Longva, Oddvar; Shaw, John

    2007-01-01

    The extent and behaviour of the southeast margin of the Laurentide Ice Sheet in Atlantic Canada is of significance in the study of Late Wisconsinan ice sheet-ocean interactions. Multibeam sonar imagery of subglacial, ice-marginal and glaciomarine landforms on German Bank, Scotian Shelf, provides evidence of the pattern of glacial-dynamic events in the eastern Gulf of Maine. Northwest-southeast trending drumlins and megaflutes dominate northern German Bank. On southern German Bank, megaflutes of thin glacial deposits create a distinct northwest-southeast grain. Lobate regional moraines (>10km long) are concave to the northwest, up-ice direction and strike southwest-northeast, normal to the direction of ice flow. Ubiquitous, overlying De Geer moraines (

  14. Differential implications of the oncogene-tumor suppressor gene complex in the geneses of 19 human neoplasias. Evidence in support of the steroid carcinogenesis hypothesis.

    PubMed

    Kodama, M; Murakami, M; Kodama, T

    1997-01-01

    The cancer risk changes of 19 human neoplasias over time and space, as expressed in terms of the logarithm of age-adjusted incidence rate (log AAIR), were found to hold a linear correlation with each other--a finding suggesting that the distribution pattern of log AAIR data sets of 2 cancers, when plotted on a two dimension diagram, may show a good fitness to the chemical equilibrium model a product of the law of mass action. On the basis of the statistical analysis of the data, we reached the conclusion that the risk changes of a given neoplasia in space represents the function of the centripetal force of an activated oncogene and the centrifugal force of an inactivated tumor suppressor gene, both of which should cooperate with each other to create a thermodynamic equilibrium under the law of mass action. The purpose of this study was to test the contribution of the oncogene-tumor suppressor gene complex to the sex discrimination of cancer risk in 19 human neoplasias. The results obtained are as follows: a) the correlation coefficient r seq of the sequential regression analysis, as applied to 47 log AAIR data sets of one tumor pair, served as a criterion in testing the balance of power between oncogene activation and tumor suppressor gene inactivation. Sole activation of the oncogene should give an r seq value of -1.0, whereas sole inactivation of the tumor suppressor gene should give an r seq value of +1.0. b) Esophageal cancer and laryngeal cancer, two sex-discriminating tumors with distinct male predominance were each associated with differential implications of the oncogene-tumor suppressor gene complex between the male and female populations: in both tumors, the male populations were associated with a complex of activated oncogene and inactivated tumor suppressor gene, whereas the female population was associated with another complex of weakly activated (esophageal cancer) or non-activated (laryngeal cancer) oncogene and inactivated tumor suppressor gene, as

  15. Genetic Evidence of Hybridization between the Endangered Native Species Iguana delicatissima and the Invasive Iguana iguana (Reptilia, Iguanidae) in the Lesser Antilles: Management Implications.

    PubMed

    Vuillaume, Barbara; Valette, Victorien; Lepais, Olivier; Grandjean, Frédéric; Breuil, Michel

    2015-01-01

    observed in recent population history over several islands. These results have profound implications for species management of the endangered I. delicatissima and practical conservation recommendations are being discussed in the light of these findings.

  16. Genetic Evidence of Hybridization between the Endangered Native Species Iguana delicatissima and the Invasive Iguana iguana (Reptilia, Iguanidae) in the Lesser Antilles: Management Implications

    PubMed Central

    Vuillaume, Barbara; Valette, Victorien; Lepais, Olivier; Grandjean, Frédéric; Breuil, Michel

    2015-01-01

    observed in recent population history over several islands. These results have profound implications for species management of the endangered I. delicatissima and practical conservation recommendations are being discussed in the light of these findings. PMID:26046351

  17. The accumulation of nickel in human lungs

    SciTech Connect

    Edelman, D.A.; Roggli, V.L. )

    1989-05-01

    Using data from published studies, lung concentrations of nickel were compare for persons with and without occupational exposure to nickel. As expected, the concentrations were much higher for persons with occupational exposure. To estimate the effects of nickel-containing tobacco smoke and nickel in the ambient air on the amount of nickel accumulated in lungs over time, a model was derived that took into account various variables related to the deposition of nickel in lungs. The model predicted nickel concentrations that were in the range of those of persons without known nickel exposure. Nickel is a suspected carcinogen and has been associated with an increased risk of respiratory tract cancer among nickel workers. However, before the nickel content of cigarettes can be implicated in the etiology of lung cancer, further studies are needed to evaluate the independent effects of smoking and exposure to nickel.

  18. Gypsum accumulation on carbonate stone

    USGS Publications Warehouse

    McGee, E.S.; Mossotti, V.G.

    1992-01-01

    The accumulation of gypsum on carbonate stone has been investigated through exposure of fresh samples of limestone and marble at monitored sites, through examination of alteration crusts from old buildings and through laboratory experiments. Several factors contribute to gypsum accumulation on carbonate stone. Marble or limestone that is sheltered from direct washing by rain in an urban environment with elevated pollution levels is likely to accumulate a gypsum crust. Crust development may be enhanced if the stone is porous or has an irregular surface area. Gypsum crusts are a surficial alteration feature; gypsum crystals form at the pore opening-air interface, where evaporation is greatest.

  19. Anthocyanins facilitate tungsten accumulation in Brassica

    SciTech Connect

    Hale, K.L.

    2002-11-01

    Accumulation of molybdenum in Brassica was recently found to be correlated with anthocyanin content, involving the formation of a blue complex. Here the role of anthocyanins in tungsten sequestration was investigated using three species of Brassica: B. rapa (cv. Fast plants), B. juncea (Indian mustard) and B. oleracea (red cabbage). Seedlings of B. rapa and B. juncea turned blue when supplied with colourless tungstate. The blue compound co-localized with anthocyanins in the peripheral cell layers, and the degree of blueness was correlated with anthocyanin content. The direct involvement of anthocyanins in the blue coloration was evident when purified anthocyanins showed a colour change from pink to blue in vitro upon addition of tungstate, over a wide pH range. Anthocyanin production was upregulated 3-fold by W in B. juncea, possibly reflecting a function for anthocyanins in W tolerance or sequestration. The presence of anthocyanins facilitated W accumulation in B. rapa: anthocyanin-containing seedlings accumulated 3-fold more W than an anthocyaninless mutant. There was no correlation between anthocyanin content and W tolerance under these conditions. The nature of the interaction between anthocyanins and tungstate was investigated. X-ray absorption spectroscopy showed no change in the local chemical environment of Wupon uptake of tungstate by the plant; HPLC analysis of purified anthocyanin with or without tungstate showed no peak shift after metal treatment.

  20. Linear Deterministic Accumulator Models of Simple Choice

    PubMed Central

    Heathcote, Andrew; Love, Jonathon

    2012-01-01

    We examine theories of simple choice as a race among evidence accumulation processes. We focus on the class of deterministic race models, which assume that the effects of fluctuations in the parameters of the accumulation processes between-choice trials (between-choice noise) dominate the effects of fluctuations occurring while making a choice (within-choice noise) in behavioral data (i.e., response times and choices). The latter deterministic approximation, when combined with the assumption that accumulation is linear, leads to a class of models that can be readily applied to simple-choice behavior because they are computationally tractable. We develop a new and mathematically simple exemplar within the class of linear deterministic models, the Lognormal race (LNR). We then examine how the LNR, and another widely applied linear deterministic model, Brown and Heathcote’s (2008) LBA, account for a range of benchmark simple-choice effects in lexical-decision task data reported by Wagenmakers et al. (2008). Our results indicate that the LNR provides an accurate description of this data. Although the LBA model provides a slightly better account, both models support similar psychological conclusions. PMID:22936920

  1. Molecular sources of residual cardiovascular risk, clinical signals, and innovative solutions: relationship with subclinical disease, undertreatment, and poor adherence: implications of new evidence upon optimizing cardiovascular patient outcomes

    PubMed Central

    Kones, Richard

    2013-01-01

    Residual risk, the ongoing appreciable risk of major cardiovascular events (MCVE) in statin-treated patients who have achieved evidence-based lipid goals, remains a concern among cardiologists. Factors that contribute to this continuing risk are atherogenic non-low-density lipoprotein (LDL) particles and atherogenic processes unrelated to LDL cholesterol, including other risk factors, the inherent properties of statin drugs, and patient characteristics, ie, genetics and behaviors. In addition, providers, health care systems, the community, public policies, and the environment play a role. Major statin studies suggest an average 28% reduction in LDL cholesterol and a 31% reduction in relative risk, leaving a residual risk of about 69%. Incomplete reductions in risk, and failure to improve conditions that create risk, may result in ongoing progression of atherosclerosis, with new and recurring lesions in original and distant culprit sites, remodeling, arrhythmias, rehospitalizations, invasive procedures, and terminal disability. As a result, identification of additional agents to reduce residual risk, particularly administered together with statin drugs, has been an ongoing quest. The current model of atherosclerosis involves many steps during which disease may progress independently of guideline-defined elevations in LDL cholesterol. Differences in genetic responsiveness to statin therapy, differences in ability of the endothelium to regenerate and repair, and differences in susceptibility to nonlipid risk factors, such as tobacco smoking, hypertension, and molecular changes associated with obesity and diabetes, may all create residual risk. A large number of inflammatory and metabolic processes may also provide eventual therapeutic targets to lower residual risk. Classically, epidemiologic and other evidence suggested that raising high-density lipoprotein (HDL) cholesterol would be cardioprotective. When LDL cholesterol is aggressively lowered to targets, low HDL

  2. Genetic evidence for hybridisation between Haemonchus contortus and Haemonchus placei in natural field populations and its implications for interspecies transmission of anthelmintic resistance.

    PubMed

    Chaudhry, Umer; Redman, Elizabeth M; Abbas, Muhammad; Muthusamy, Raman; Ashraf, Kamran; Gilleard, John S

    2015-02-01

    introgression of drug resistance loci. We believe this is the first definitive genetic evidence of hybridisation between H. contortus and H. placei in the field and represents the most comprehensive genetic evidence of F1 hybrids between any human or livestock parasitic nematode species to date. Further, it suggests that interspecies transmission of anthelmintic resistance mutations warrants further investigation. PMID:25449043

  3. Evidence for a Non-Genomic Action of Testosterone in Skeletal Muscle Which may Improve Athletic Performance: Implications for the Female Athlete

    PubMed Central

    Dent, Jessica R.; Fletcher, Deborah K.; McGuigan, Michael R.

    2012-01-01

    This review will focus on the proposed second mode of testosterone action (now termed non-genomic) that appears to occur independently of the traditional transcriptional mechanism in mammalian skeletal muscle cells which may enhance skeletal muscle contractile properties. This mechanism of testosterone action differs from the traditional pathway, originating at the cell membrane, having a rapid onset of action, requiring second messengers to execute its effects and is insensitive to inhibitors of traditional androgen receptor action, transcription and protein synthesis. Importantly, unlike the traditional action of testosterone in skeletal muscle, this non-genomic pathway is shown to have a direct acute effect on calcium-dependent components important for the contractile process. The changes within the contractile apparatus may enhance the ability of the muscle to produce explosive power during athletic performance. Rapid increases in Inositol triphosphate mass and calcium release from the sarcoplasmic reticulum have been reported in rodent skeletal muscle cells, and a rapid androgen (dihydrotestosterone)-induced increase in peak force production has been recorded in intact rodent skeletal muscle fibre bundles while showing increases in the activity of the Ras/MAP/ERK mediated pathway. Because the non-genomic action of testosterone is enhanced during increases in exposure to testosterone and is acute in its action, implications for athletic performance are likely greater in females than males due to natural fluctuations in circulating testosterone levels during the female menstrual cycle, reproductive pathology, and changes induced by hormonal contraceptive methods. Research should be undertaken in humans to confirm a pathway for non-genomic testosterone action in human skeletal muscle. Specifically, relationships between testosterone fluctuations and physiological changes within skeletal muscle cells and whole muscle exercise performance need to be examined. Key

  4. Evidence for Late Eocene emplacement of the Malaita Terrane, Solomon Islands: Implications for an even larger Ontong Java Nui oceanic plateau

    NASA Astrophysics Data System (ADS)

    Musgrave, Robert J.

    2013-06-01

    Most tectonic models for the Solomon Islands Arc invoke a Miocene collision with the Ontong Java Plateau (OJP) to halt cessation of Pacific Plate subduction, initiate Australian Plate subduction, and emplace the Malaita Terrane, which shares the characteristic basement age and geochemistry of OJP. Existing paleomagnetic evidence, however, required the Malaita Terrane to have been fixed to the arc from at least the Late Eocene. New sampling has yielded a paleomagnetic pole from Aptian-Albian limestones and mudstones that falls between the apparent polar wander paths for the Australian Plate and OJP, confirming the extended period of residence of the Malaita Terrane on the arc. Arc-derived turbidities within Late Eocene through Miocene limestones on Malaita and Santa Isabel, and related clasts in broadly contemporary sandstones and conglomerates on Santa Isabel, also attest to early emplacement. Modeling the emplacement at 35 Ma satisfies both the paleomagnetic data and the sediment provenance. Continuing the reconstruction to 125 Ma leaves the Malaita Terrane far from OJP at the time of plateau formation. OJP is now understood to have formed as part of a larger Ontong Java Nui, also comprising the Hikurangi and Manihiki plateaus, separated by spreading during the Cretaceous. Restoring the separation of the known elements, and invoking an additional triple junction, unites the (now largely subducted) Malaita Terrane with the rest of Ontong Java Nui. Subduction of substantial areas of the Ontong Java Nui plateau, with little geological signal other than a reduction in arc volcanism, is a corollary.

  5. Life-long Programming Implications of Exposure to Tobacco Smoking and Nicotine Before and Soon After Birth: Evidence for Altered Lung Development

    PubMed Central

    Maritz, Gert S.; Harding, Richard

    2011-01-01

    Tobacco smoking during pregnancy remains common, especially in indigenous communities, and likely contributes to respiratory illness in exposed offspring. It is now well established that components of tobacco smoke, notably nicotine, can affect multiple organs in the fetus and newborn, potentially with life-long consequences. Recent studies have shown that nicotine can permanently affect the developing lung such that its final structure and function are adversely affected; these changes can increase the risk of respiratory illness and accelerate the decline in lung function with age. In this review we discuss the impact of maternal smoking on the lungs and consider the evidence that smoking can have life-long, programming consequences for exposed offspring. Exposure to maternal tobacco smoking and nicotine intake during pregnancy and lactation changes the genetic program that controls the development and aging of the lungs of the offspring. Changes in the conducting airways and alveoli reduce lung function in exposed offspring, rendering the lungs more susceptible to obstructive lung disease and accelerating lung aging. Although it is generally accepted that prevention of maternal smoking during pregnancy and lactation is essential, current knowledge of the effects of nicotine on lung development does not support the use of nicotine replacement therapy in this group. PMID:21556184

  6. 10Be evidence for delayed acquisition of remanent magnetization in marine sediments: Implication for a new age for the Matuyama-Brunhes boundary

    NASA Astrophysics Data System (ADS)

    Suganuma, Yusuke; Yokoyama, Yusuke; Yamazaki, Toshitsugu; Kawamura, Kenji; Horng, Chorng-Shern; Matsuzaki, Hiroyuki

    2010-08-01

    Fluxes of the meteoric cosmogenic radionuclide 10Be vary with changes in the incoming cosmic rays modulated by geomagnetic field intensity variations. The variability in the 10Be flux can be used to synchronize ice cores, as well as marine sediments, by comparison with the relative paleointensity variations of the geomagnetic field. However, lock-in of the paleomagnetic signal at some depth below the sediment-water interface in marine sediments through acquisition of a post-depositional remanent magnetization (PDRM) adds uncertainty to synchronization. Despite the long history of such studies, the magnitude of the PDRM lock-in depth remains controversial. In this article, we present clear evidence for a downward offset of the paleointensity minimum relative to the 10Be flux anomaly at the Matuyama-Brunhes (M-B) geomagnetic polarity boundary, which we interpret to result from a ˜ 15 cm PDRM lock in depth. This lock-in depth indicates that up to several tens of thousands years of age offset probably occurs when a paleomagnetic record is used for dating marine sediments, and the age of the M-B boundary should be revised to ca. 10 kyr younger, which is consistent with a younger ice core derived age of 770 ± 6 ka (2 σ). This cosmogenic age tuning strategy will contribute to refining paleomagnetic-based age models for marine sediments and identifying of lead-lag relationships for global abrupt environmental changes.

  7. Evidence for spreading in the lower Kam Group of the Yellowknife greenstone belt: Implications for Archaean basin evolution in the Slave Province

    NASA Technical Reports Server (NTRS)

    Helmstaedt, H.; Padgham, W. A.

    1986-01-01

    The Yellowknife greenstone belt is the western margin of an Archean turbidite-filled basin bordered on the east by the Cameron River and Beaulieu River volcanic belts (Henderson, 1981; Lambert, 1982). This model implies that rifting was entirely ensialic and did not proceed beyond the graben stage. Volcanism is assumed to have been restricted to the boundary faults, and the basin was floored by a downfaulted granitic basement. On the other hand, the enormous thickness of submarine volcanic rocks and the presence of a spreading complex at the base of the Kam Group suggest that volcanic rocks were much more widespread than indicated by their present distribution. Rather than resembling volcanic sequences in intracratonic graben structures, the Kam Group and its tectonic setting within the Yellowknife greenstone belt have greater affinities to the Rocas Verdes of southern Chile, Mesozoic ophiolites, that were formed in an arc-related marginal basin setting. The similarities of these ophiolites with some Archean volcanic sequences was previously recognized, and served as basis for their marginal-basin model of greenstone belts. The discovery of a multiple and sheeted dike complex in the Kam Group confirms that features typical of Phanerozoic ophiolites are indeed preserved in some greenstone belts and provides further field evidence in support of such a model.

  8. Evidence Supporting a Role for SMAD2/3 in Bovine Early Embryonic Development: Potential Implications for Embryotropic Actions of Follistatin1

    PubMed Central

    Zhang, Kun; Rajput, Sandeep K.; Lee, Kyung-Bon; Wang, Dongliang; Huang, Juncheng; Folger, Joseph K.; Knott, Jason G.; Zhang, Jiuzhen; Smith, George W.

    2015-01-01

    The TGF-beta-SMAD signaling pathway is involved in regulation of various aspects of female reproduction. However, the intrinsic functional role of SMADs in early embryogenesis remains poorly understood. Previously, we demonstrated that treatment with follistatin, an activin (TGF-beta superfamily ligand)-binding protein, is beneficial for bovine early embryogenesis and specific embryotropic actions of follistatin are dependent on SMAD4. Because SMAD4 is a common SMAD that can bind both SMAD2/3 and SMAD1/5, the objective of this study was to further determine the intrinsic role of SMAD2/3 in the control of early embryogenesis and delineate if embryotropic actions of follistatin in early embryos are SMAD2/3 dependent. By using a combination of pharmacological and small interfering RNA-mediated inhibition of SMAD2/3 signaling in the presence or absence of follistatin treatment, our results indicate that SMAD2 and SMAD3 are both required for bovine early embryonic development and stimulatory actions of follistatin on 8- to 16-cell and that blastocyst rates, but not early cleavage, are muted when SMAD2/3 signaling is inhibited. SMAD2 deficiency also results in reduced expression of the bovine trophectoderm cell-specific gene CTGF. In conclusion, the present work provides evidence supporting a functional role of SMAD2/3 in bovine early embryogenesis and that specific stimulatory actions of follistatin are not observed in the absence of SMAD2/3 signaling. PMID:26289443

  9. Evidence of local short-distance spawning migration of tropical freshwater eels, and implications for the evolution of freshwater eel migration

    PubMed Central

    Arai, Takaomi

    2014-01-01

    Freshwater eels have fascinated biologists for centuries due to the spectacular long-distance migrations between the eels’ freshwater habitats and their spawning areas far out in the ocean and the mysteries of their ecology. The spawning areas of Atlantic eels and Japanese eel were located far offshore in the Atlantic Ocean and the Pacific Ocean, respectively, and their reproduction took place thousands of kilometers away from their growth habitats. Phylogenetic studies have revealed that freshwater eels originated in the Indonesian region. However, remarkably little is known about the life histories of tropical freshwater eels despite the fact that tropical eels are key to understanding the nature of primitive forms of catadromous migration. This study found spawning-condition tropical freshwater eels in Lake Poso, central Sulawesi, Indonesia, with considerably high gonadosomatic index values and with histologically fully developed gonads. This study provides the first evidence that under certain conditions, freshwater eels have conditions that are immediately able to spawn even in river downstream. The results suggest that, in contrast to the migrations made by the Atlantic and Japanese eels, freshwater eels originally migrated only short distances of <100 kilometers to local spawning areas adjacent to their freshwater growth habitats. Ancestral eels most likely underwent a catadromous migration from local short-distance movements in tropical coastal waters to the long-distance migrations characteristic of present-day temperate eels, which has been well established as occurring in subtropical gyres in both hemispheres. PMID:25614795