Science.gov

Sample records for short-term dissolution response

  1. Impact of iron chelators on short-term dissolution of basaltic glass

    NASA Astrophysics Data System (ADS)

    Perez, Anne; Rossano, Stéphanie; Trcera, Nicolas; Verney-Carron, Aurélie; Huguenot, David; van Hullebusch, Eric D.; Catillon, Gilles; Razafitianamaharavo, Angelina; Guyot, François

    2015-08-01

    Although microorganisms seem to play an important role in the alteration processes of basaltic glasses in solution, the elementary mechanisms involved remain unclear in particular with regard to the role of organic ligands excreted by the cells. Two glasses, one with Fe and one without Fe were synthesized to model basaltic glass compositions. Fe in the glass was mostly Fe(III) for enhancing interaction with siderophores, yet with small but significant amounts of Fe(II) (between 10% and 30% of iron). The prepared samples were submitted to abiotic alteration experiments in buffered (pH 6.4) diluted solutions of metal-specific ligands, namely oxalic acid (OA, 10 mM), desferrioxamine (DFA, 1 mM) or 2,2‧-bipyridyl (BPI, 1 mM). Element release from the glass into the solution after short term alteration (maximum 1 week) was measured by ICP-OES, and normalized mass losses and relative release ratios (with respect to Si) were evaluated for each element in each experimental condition. The presence of organic ligands had a significant effect on the dissolution of both glasses. Trivalent metals chelators (OA, DFA) impacted on the release of Fe3+ and Al3+, and thus on the global dissolution of both glasses, enhancing all release rates and dissolution stoichiometry (release rates were increased up to 7 times for Al or Fe). As expected, the mostly divalent metal chelator BPI interacted preferentially with Ca2+, Mg2+ and Fe2+. This study thus allows to highlight the central roles of iron and aluminium in interaction with some organic ligands in the alteration processes of basaltic glasses. It thus provides a step toward understanding the biological contribution of this fundamental geological process.

  2. Acute psychological stress induces short-term variable immune response.

    PubMed

    Breen, Michael S; Beliakova-Bethell, Nadejda; Mujica-Parodi, Lilianne R; Carlson, Joshua M; Ensign, Wayne Y; Woelk, Christopher H; Rana, Brinda K

    2016-03-01

    In spite of advances in understanding the cross-talk between the peripheral immune system and the brain, the molecular mechanisms underlying the rapid adaptation of the immune system to an acute psychological stressor remain largely unknown. Conventional approaches to classify molecular factors mediating these responses have targeted relatively few biological measurements or explored cross-sectional study designs, and therefore have restricted characterization of stress-immune interactions. This exploratory study analyzed transcriptional profiles and flow cytometric data of peripheral blood leukocytes with physiological (endocrine, autonomic) measurements collected throughout the sequence of events leading up to, during, and after short-term exposure to physical danger in humans. Immediate immunomodulation to acute psychological stress was defined as a short-term selective up-regulation of natural killer (NK) cell-associated cytotoxic and IL-12 mediated signaling genes that correlated with increased cortisol, catecholamines and NK cells into the periphery. In parallel, we observed down-regulation of innate immune toll-like receptor genes and genes of the MyD88-dependent signaling pathway. Correcting gene expression for an influx of NK cells revealed a molecular signature specific to the adrenal cortex. Subsequently, focusing analyses on discrete groups of coordinately expressed genes (modules) throughout the time-series revealed immune stress responses in modules associated to immune/defense response, response to wounding, cytokine production, TCR signaling and NK cell cytotoxicity which differed between males and females. These results offer a spring-board for future research towards improved treatment of stress-related disease including the impact of stress on cardiovascular and autoimmune disorders, and identifies an immune mechanism by which vulnerabilities to these diseases may be gender-specific.

  3. Airway response to ultra short-term exposure to ozone

    SciTech Connect

    Fouke, J.M.; Delemos, R.A.; McFadden, E.R. Jr.

    1988-02-01

    To determine whether acute short-term exposure to oxidant pollutants can cause changes in respiratory mechanics, we gave 0.5 ppm ozone for 5 min to 7 baboons. We measured pulmonary resistance (RL) and obtained dose response curves to methacholine before and after the exposures. This brief insult increased resistance (control RL = 1.53 +/- 0.21 cm H/sub 2/O.L-1 s; post-ozone RL = 3.53 +/- 0.54 cm H/sub 2/O.L-1 s). On a second occasion, 6 of these animals were restudied before and after the administration of cromolyn sodium. Although this drug had no effect on the measurements of mechanics made in the control period, it significantly reduced the ozone-induced changes in mechanics. The increase in RL was 52% of that produced in the first study. The results demonstrated that the ozone injury with its acute and subacute airway sequelae occurs quite rapidly and after very brief exposure. The time course of the change in mechanics and the effects of cromolyn suggest the hypothesis that surface epithelial cells are disrupted, causing subsequent release of bronchoconstricting agents.

  4. Short-term cholinergic desensitization of rat pancreatic secretory response

    SciTech Connect

    Asselin, J.; Larose, L.; Morisset, J.

    1987-03-01

    Dispersed pancreatic acini were first exposed to carbamylcholine (10/sup -7/-10/sup -4/ M) for 60 min, washed, and reexposed to this same agonist (10/sup -8/-10/sup -3/ M) for 15 min. During this second incubation, the functional secretory capacity of these acini was evaluated by measuring amylase release. Acini preexposed to concentrations of carbamylcholine of 10/sup -6/ M or greater showed shifts to the right in the subsequent carbamylcholine dose-response curves of amylase release. A 3-h recovery period (without carbamylcholine) did not restore the altered carbamylcholine dose-response curve. Ca/sup 2 +/ concentrations of 10/sup -7/ M or 2.5 x 10/sup -3/ M instead of 0.5 x 10/sup -3/ M during the 60-min preincubation did not affect the desensitization process. With use of N-(/sup 3/H)methylscopolamine to evaluate muscarinic receptors, the only changes observed after desensitization were a significant decrease in the high-affinity and an equivalent increase in that of the low-affinity receptors. After cholinergic exposure amylase release stimulated by caerulein was only slightly modified, whereas amylase release in response to a phorbol ester 12-O-tetradecanoylphorbol-13-acetate and to the ionophore A23187 was not altered. These data indicate that short-term desensitization with a cholinergic agent is relatively specific to muscarinic agonists, causes changes in the muscarinic receptor high-and low-affinity concentration but does not alter intracellular steps after calcium mobilization or protein kinase C activation known to be involved in the secretion process.

  5. Short-Term Variations in Response Distribution to Cortical Stimulation

    ERIC Educational Resources Information Center

    Lesser, Ronald P.; Lee, Hyang Woon; Webber, W. R. S.; Prince, Barry; Crone, Nathan E.; Miglioretti, Diana L.

    2008-01-01

    Patterns of responses in the cerebral cortex can vary, and are influenced by pre-existing cortical function, but it is not known how rapidly these variations can occur in humans. We investigated how rapidly response patterns to electrical stimulation can vary in intact human brain. We also investigated whether the type of functional change…

  6. Response Feedback and Short-Term Motor Retention

    ERIC Educational Resources Information Center

    Adams, Jack A; And Others

    1972-01-01

    The hypothesis was tested that forgetting could be found on one trial in the absence of interference if the conditions or response-produced feedback were sufficiently reduced. The task was the learning and recall of a linear movement. (Author)

  7. Control group response variability in short-term toxicity tests

    SciTech Connect

    Gast, L.C.; Shimp, C.; Wang, Q.; Shukla, R.; Fulk, F.

    1995-12-31

    The US EPA`s National Reference Toxicant Database (NRTDB) has afforded an excellent opportunity to examine and document variability in responses within control groups (i.e. zero concentration of the toxicant.) The NRTDB has compiled acute and chronic reference toxicant test results for eight species and currently contains results for 32 laboratories and generally eight to ten tests for a species within each laboratory. The Ceriodaphnia dubia Survival and Reproduction test and the Pimephales promelas (fathead minnow) Survival and Growth test are the most frequently represented chronic tests with 331 and 144 sets of test data, respectively. For this presentation, Ceriodaphnia dubia reproduction data, expressed as total numbers of young in the test period, and fathead minnow survival and growth data were analyzed using a variance components model. The information regarding the control population is useful in examining the sources of inter and intralaboratory variability of chronic testing. In addition, this control population response variability information will be valuable for characterizing what can be termed as ``practically equivalent responses`` between a control and an effluent. The preliminary analysis indicates considerable between-test variability; however, this variability is not consistent across laboratories. Results of further exploration on this issue will be presented.

  8. Response of middle atmosphere to short-term solar ultraviolet variations: 1. observations

    SciTech Connect

    Keating, G.M.; Pitts, M.C.; Brasseur, G.; De Rudder, A.

    1987-01-20

    A series of studies were performed concerning the response of low-latitude ozone and temperature in the stratosphere and mesosphere to short-term solar ultraviolet variability associated with the rotation of the sun.

  9. Temporal Prediction Errors Affect Short-Term Memory Scanning Response Time.

    PubMed

    Limongi, Roberto; Silva, Angélica M

    2016-11-01

    The Sternberg short-term memory scanning task has been used to unveil cognitive operations involved in time perception. Participants produce time intervals during the task, and the researcher explores how task performance affects interval production - where time estimation error is the dependent variable of interest. The perspective of predictive behavior regards time estimation error as a temporal prediction error (PE), an independent variable that controls cognition, behavior, and learning. Based on this perspective, we investigated whether temporal PEs affect short-term memory scanning. Participants performed temporal predictions while they maintained information in memory. Model inference revealed that PEs affected memory scanning response time independently of the memory-set size effect. We discuss the results within the context of formal and mechanistic models of short-term memory scanning and predictive coding, a Bayes-based theory of brain function. We state the hypothesis that our finding could be associated with weak frontostriatal connections and weak striatal activity.

  10. Determinants and short-term physiological consequences of PHA immune response in lesser kestrel nestlings.

    PubMed

    Rodríguez, Airam; Broggi, Juli; Alcaide, Miguel; Negro, Juan José; Figuerola, Jordi

    2014-08-01

    Individual immune responses are likely affected by genetic, physiological, and environmental determinants. We studied the determinants and short-term consequences of Phytohaemagglutinin (PHA) induced immune response, a commonly used immune challenge eliciting both innate and acquired immunity, on lesser kestrel (Falco naumanni) nestlings in semi-captivity conditions and with a homogeneous diet composition. We conducted a repeated measures analyses of a set of blood parameters (carotenoids, triglycerides, β-hydroxybutyrate, cholesterol, uric acid, urea, total proteins, and total antioxidant capacity), metabolic (resting metabolic rate), genotypic (MHC class II B heterozygosity), and biometric (body mass) variables. PHA challenge did not affect the studied physiological parameters on a short-term basis (<12 hr), except plasma concentrations of triglycerides and carotenoids, which decreased and increased, respectively. Uric acid was the only physiological parameter correlated with the PHA induced immune response (skin swelling), but the change of body mass, cholesterol, total antioxidant capacity, and triglycerides between sessions (i.e., post-pre treatment) were also positively correlated to PHA response. No relationships were detected between MHC gene heterozygosity or resting metabolic rate and PHA response. Our results indicate that PHA response in lesser kestrel nestlings growing in optimal conditions does not imply a severe energetic cost 12 hr after challenge, but is condition-dependent as a rapid mobilization of carotenoids and decrease of triglycerides is elicited on a short-term basis.

  11. Frequency-selective augmenting responses by short-term synaptic depression in cat neocortex

    PubMed Central

    Houweling, Arthur R; Bazhenov, Maxim; Timofeev, Igor; Grenier, François; Steriade, Mircea; Sejnowski, Terrence J

    2002-01-01

    Thalamic stimulation at frequencies between 5 and 15 Hz elicits incremental or ‘augmenting’ cortical responses. Augmenting responses can also be evoked in cortical slices and isolated cortical slabs in vivo. Here we show that a realistic network model of cortical pyramidal cells and interneurones including short-term plasticity of inhibitory and excitatory synapses replicates the main features of augmenting responses as obtained in isolated slabs in vivo. Repetitive stimulation of synaptic inputs at frequencies around 10 Hz produced postsynaptic potentials that grew in size and carried an increasing number of action potentials resulting from the depression of inhibitory synaptic currents. Frequency selectivity was obtained through the relatively weak depression of inhibitory synapses at low frequencies, and strong depression of excitatory synapses together with activation of a calcium-activated potassium current at high frequencies. This network resonance is a consequence of short-term synaptic plasticity in a network of neurones without intrinsic resonances. These results suggest that short-term plasticity of cortical synapses could shape the dynamics of synchronized oscillations in the brain. PMID:12122156

  12. Responses of Ulva prolifera to short-term nutrient enrichment under light and dark conditions

    NASA Astrophysics Data System (ADS)

    Sun, Kai-Ming; Li, Ruixiang; Li, Yan; Xin, Ming; Xiao, Jie; Wang, Zongling; Tang, Xuexi; Pang, Min

    2015-09-01

    To define responses of short-term nutrient uptake in Ulva prolifera, we measured uptake rates, enzyme activity, and tissue nutrient content in lab experiments where we manipulated nutrient supply and irradiation. Nitrate uptake of U. prolifera was significantly impacted by the external nitrate concentrations, and ammonium uptake was mainly determined by the light availability. The measured nitrogen contents in tissues were higher than the calculated values from the uptake of dissolve inorganic nitrogen, indicating that U. prolifera might use multiple nitrogen sources. High external phosphate concentrations and sufficient light can accelerate the phosphate uptake of U. prolifera, while the measured phosphorus contents in tissues were lower than the calculated values from the uptake of phosphate, suggesting a possibility of internal phosphorus release. The enzymatic activities of nitrate reductase (NR), acid phosphatase (AcP) and alkaline phosphatase (AP) showed little changes, indicating that enzymatic activity might not a direct factor determining the short-term nutrient uptake of U. prolifera.

  13. Root metabolic responses to short term anaerobiosis in the temperate sea grass Zostera marina L

    SciTech Connect

    Smith, R.D.; Pregnall, A.M.; Alberte, R.S.

    1986-04-01

    The submerged angiosperm Z. marina grows in highly reducing marine sediments. The roots experience periods of oxygen deprivation at night when photosynthesis-mediated oxygen transport from the shoot ceases. Despite this apparently inhospitable environment, Z. marina is extremely productive. This study sought to determine root metabolic responses to short term anaerobiosis. Roots were incubated for 4 h in the presence of /sup 14/C-sucrose. Amino acids and Krebs cycle intermediates were then extracted and label was quantified. Ethanol and lactate were the most heavily labeled metabolites following short term anaerobiosis. Despite increased synthesis of ethanol during anaerobiosis, endogenous levels do not increase significantly. Instead over 90% of newly synthesized ethanol is released by roots into the incubation medium. The authors conclude that release of ethanol by roots occurs naturally and prevents excessive accumulation of a potentially toxic product.

  14. Are baseline and short-term corticosterone stress responses in free-living amphibians repeatable?

    PubMed

    Narayan, Edward J; Cockrem, John F; Hero, Jean-Marc

    2013-01-01

    Amphibians respond to environmental stressors by secreting corticosterone, a stress hormone which promotes physiological and behavioral responses. Capture handling can be used to stimulate physiological stress response in amphibians. The use of single blood sampling and presentation of mean data often limits the quantification of within and between individual variation in baseline and short-term corticosterone stress responses in amphibians. It is important for studies of amphibian physiological ecology to determine whether baseline and short-term corticosterone stress responses are consistent or not. We quantified repeatability (r), a statistical measure of consistency, in baseline and short-term corticosterone stress responses to a standard capture and handling stress protocol in free-living adult male cane toads (Rhinella marina). Corticosterone metabolite concentrations were measured entirely non-invasively in male toad urine samples via an enzyme-immunoassay. During the first sampling occasion, urine samples were collected manually from individual male toads (n=20) immediately upon field capture. Toads were handled for 5min then transferred to plastic bags (constituting a mild stressor), and urine samples were collected hourly over 8h in the field. The toads were resampled for baseline (0h) urine corticosterone with hourly urine sampling over 8h (for quantification of the stress induced corticosterone) at 14 day intervals on three consecutive occasions. Within and between sample variations in urinary corticosterone metabolite concentrations were also quantified. All toads expressed a corticosterone stress response over 8h to our standard capture and handling stress protocol. Variations both within and between toads was higher for corrected integrated corticosterone concentrations than corticosterone concentrations at baseline, 3 or 6h. Baseline urinary corticosterone metabolite concentration of the male toads was highly repeatable (r=0.877) together with high

  15. Long- and short-term temperature responses of microbially-mediated boreal soil organic matter transformations

    NASA Astrophysics Data System (ADS)

    Min, K.; Buckeridge, K. M.; Edwards, K. A.; Ziegler, S. E.; Billings, S. A.

    2015-12-01

    Microorganisms use exoenzymes to decay soil organic matter into assimilable substrates, some of which are transformed into CO2. Microbial CO2 efflux contributes up to 60% of soil respiration, a feature that can change with temperature due to altered exoenzyme activities (short-term) and microbial communities producing different exoenzymes (longer-term). Often, however, microbial temperature responses are masked by factors that also change with temperature in soil, making accurate projections of microbial CO2 efflux with warming challenging. Using soils along a natural climate gradient similar in most respects except for temperature regime (Newfoundland Labrador Boreal Ecosystem Latitudinal Transect), we investigated short-vs. long-term temperature responses of microbially-mediated organic matter transformations. While incubating soils at 5, 15, and 25°C for 84 days, we measured exoenzyme activities, CO2 efflux rates and biomass, and extracted DNA at multiple times. We hypothesized that short-term, temperature-induced increases in exoenzyme activities and CO2 losses would be smaller in soils from warmer regions, because microbes presumably adapted to warmer regions should use assimilable substrates more efficiently and thus produce exoenzymes at a lower rate. While incubation temperature generally induced greater exoenzyme activities (p<0.001), exoenzymes' temperature responses depended on enzymes and regions (p<0.001). Rate of CO2 efflux was affected by incubation temperature (P<0.001), but not by region. Microbial biomass and DNA sequencing will reveal how microbial community abundance and composition change with short-vs. longer-term temperature change. Though short-term microbial responses to temperature suggest higher CO2 efflux and thus lower efficiency of resource use with warming, longer-term adaptations of microbial communities to warmer climates remain unknown; this work helps fill that knowledge gap.

  16. Detection of stratospheric HNO3 and NO2 response to short-term solar ultraviolet variability

    NASA Astrophysics Data System (ADS)

    Keating, G. M.; Nicholson, J., III; Brasseur, G.; de Rudder, A.; Schmailzl, U.

    1986-07-01

    It is pointed out that variations in the solar ultraviolet irradiance with a period equal to or approximately one-half of the rotation period of the sun are currently observed by satellite monitoring. Information regarding the response of stratospheric species to solar ultraviolet variability is indispensable for an understanding of the photochemical behavior of the middle atmosphere. Relations are considered between LIMS (limb infrared monitor of the stratosphere) measurements of HNO3 and NO2, and the SBUV (solar backscatter ultraviolet) measurements of short-term variations in 205-nm radiation. It is found that the response of HNO3 is much stronger than, but in the opposite sense to the ozone response, while the NO2 response is in the opposite sense to the HNO3 response. Model calculations predict large variations in HNO3 over the 11-yr solar cycle.

  17. Response to short term ultraviolet stress in the reef-building coral Pocillopora capitata (Anthozoa: Scleractinia).

    PubMed

    Liñán-Cabello, Marco A; Flores-Ramírez, Laura A; Cobo-Díaz, José Francisco; Zenteno-Savin, Tania; Olguín-Monroy, Norma O; Olivos-Ortiz, Aramís; Tintos-Gómez, Adrián

    2010-03-01

    Coral reefs are impacted by a range of environmental variables that affect their growth and survival, the main factors being the high irradiance and temperature fluctuations. Specimens of Pocillopora capitata Verrill 1864 were exposed to photosynthetically active radiation (PAR) and ultraviolet radiation (UVR) for 32 h under laboratory conditions. We examined lipid peroxidation (MDA), antioxidant enzyme activities (SOD, CAT, GPx and GST), chlorophyll a (Chl a), carotenoid pigments (CPs), mycosporine-like amino acids (MAAs), and expulsion of zooxanthellae. Our results revealed that corals exposed to UVR had relatively low levels of carotenoids and antioxidant enzyme activities compared to those exposed to PAR, as well as lower CPs/Chl a ratios. Although MAAs and CPs are rapidly produced as non-enzymatic antioxidants in response to UVR in corals, these were not sufficient, even in the dark phase of the experiment, to mitigate the damage caused by formation of reactive oxygen species (ROS), which caused breakdown of the symbiotic relationship between the zooxanthellae and the host animal to an extent 33 times greater than in the PAR treatment. In this study, it could be possible to distinguish that, parallel to the short-term adjustments, such as the amount of pigment in the algae or the sensitivity of the photosynthetic response reported in other species of coral, P. capitata exhibits at the enzymatic level a series of responses oriented to resist the effects derived from the propagation of ROS and, thus, to adapt to and maintain its reproductive capacity in shallow oceanic environments that commonly exhibit high UVR levels. Nevertheless, as a result of the inappropriate location of the artificial intercommunication structure of the Juluapan Lagoon with respect to the arrecifal area of study and therefore of the tides influence, other variables, such as the changes in short-term in turbidity, sediment inputs, nutrients, temperature and osmolarity, can act in

  18. Eucalyptus urograndis stem proteome is responsive to short-term cold stress.

    PubMed

    Leonardi, Gabriela de Almeida; Carlos, Natália Aparecida; Mazzafera, Paulo; Balbuena, Tiago Santana

    2015-05-01

    Eucalyptus urograndis is a hybrid eucalyptus of major economic importance to the Brazilian pulp and paper industry. Although widely used in forest nurseries around the country, little is known about the biochemical changes imposed by environmental stress in this species. In this study, we evaluated the changes in the stem proteome after short-term stimulation by exposure to low temperature. Using two-dimensional gel electrophoresis coupled to high-resolution mass spectrometry-based protein identification, 12 proteins were found to be differentially regulated and successfully identified after stringent database searches against a protein database from a closely related species (Eucalyptus grandis). The identification of these proteins indicated that the E. urograndis stem proteome responded quickly to low temperature, mostly by down-regulating specific proteins involved in energy metabolism, protein synthesis and signaling. The results of this study represent the first step in understanding the molecular and biochemical responses of E. urograndis to thermal stress.

  19. Maternal separation modulates short-term behavioral and physiological indices of the stress response.

    PubMed

    Litvin, Yoav; Tovote, Philip; Pentkowski, Nathan S; Zeyda, Thomas; King, Lanikea B; Vasconcellos, Amy J; Dunlap, Christopher; Spiess, Joachim; Blanchard, D Caroline; Blanchard, Robert J

    2010-07-01

    Early-life stress produces an anxiogenic profile in adulthood, presumably by activating the otherwise quiescent hypothalamic-pituitary-adrenal (HPA) axis during the vulnerable 'stress hyporesponsive period'. While the long-term effects of such early-life manipulations have been extensively characterized, little is known of the short-term effects. Here, we compared the short-term effects of two durations of maternal separation stress and one unseparated group (US) on behavioral and physiological indices of the stress response in rat pups. Separations included 3h on each of 12days, from postnatal day (PND) 2 to 13 (MS2-13) and 3days of daily, 6-h separation from PND11-13 (MS11-13). On PND14 (Experiment 1), both MS2-13 and MS11-13 produced marked reductions in freezing toward an adult male conspecific along with reduced levels of glucocorticoid type 2 (GR) and CRF type-1 (CRF(1)) receptor mRNA in the hippocampus. Group MS2-13 but not MS11-13 produced deficits in stressor-induced corticosterone secretion, accompanied by reductions in body weight. Our results suggest that GR and/or CRF(1) levels, not solely the magnitude of corticosterone secretion, may be involved in the modulation of freezing. In a second experiment, we aimed to extend these findings by testing male and female separated and unseparated pups' unconditioned defensive behaviors to cat odor on PND26, and subsequent cue+context conditioning and extinction throughout postnatal days 27-32. Our results show that maternal separation produced reductions in unconditioned freezing on PND26, with MS2-13 showing stronger deficits than MS11-13. However, separation did not affect any other defensive behaviors. Furthermore, separated rats failed to show conditioned freezing, although they did avoid the no-odor block conditioned cue. There were no sex differences other than weight. We suggest that maternal separation may have produced these changes by disrupting normal development of hippocampal regions involved in

  20. Response of middle atmosphere to short-term solar ultraviolet variations. I - Observations. II - Theory

    NASA Technical Reports Server (NTRS)

    Keating, G. M.; Pitts, M. C.; Brasseur, G.; De Rudder, A.

    1987-01-01

    The effects of solar UV variability on ozone and temperature are studied using Nimbus 7 stratospheric and mesospheric ozone, temperature, and 205-nm solar UV data, and Solar Mesosphere Explorer 1.27-micron ozone and 121.6-nm solar UV data. Consideration is given to the temperature/UV relation, the O3/UV relation with and without temperature feedback, and the responses of HNO3 and NO2 to solar UV variability. It is observed that the response times of temperature to solar UV variability are 6 days at 2 mbar and 1 day at 0.01 mbar. The stratospheric ozone response (with no correction for temperature effects) increases, while in the mesosphere a decrease is detected. The responses of ozone and temperature to solar variability are examined and calculated using a one-dimensional chemical-radiative time-dependent model. The comparison of the model results with the satellite-observed responses reveals generally good correlation between the data; however, the model predicts a larger time lag of the temperature response and a larger stratospheric HNO3 mixing ratio than the satellite data. It is noted that the relation between short-term variations in the solar UV radiation and stratospheric ozone is affected by the coupling between ozone and temperature.

  1. Transcriptome Profiling of Watermelon Root in Response to Short-Term Osmotic Stress

    PubMed Central

    Yang, Yongchao; Mo, Yanling; Yang, Xiaozheng; Zhang, Haifei; Wang, Yongqi; Li, Hao; Wei, Chunhua; Zhang, Xian

    2016-01-01

    Osmotic stress adversely affects the growth, fruit quality and yield of watermelon (Citrullus lanatus (Thunb.) Matsum. & Nakai). Increasing the tolerance of watermelon to osmotic stress caused by factors such as high salt and water deficit is an effective way to improve crop survival in osmotic stress environments. Roots are important organs in water absorption and are involved in the initial response to osmosis stress; however, few studies have examined the underlying mechanism of tolerance to osmotic stress in watermelon roots. For better understanding of this mechanism, the inbred watermelon accession M08, which exhibits relatively high tolerance to water deficits, was treated with 20% polyethylene glycol (PEG) 6000. The root samples were harvested at 6 h after PEG treatment and untreated samples were used as controls. Transcriptome analyses were carried out by Illumina RNA sequencing. A total of 5246 differentially expressed genes were identified. Gene ontology enrichment and biochemical pathway analyses of these 5246 genes showed that short-term osmotic stress affected osmotic adjustment, signal transduction, hormone responses, cell division, cell cycle and ribosome, and M08 may repress root growth to adapt osmotic stress. The results of this study describe the watermelon root transcriptome under osmotic stress and propose new insight into watermelon root responses to osmotic stress at the transcriptome level. Accordingly, these results allow us to better understand the molecular mechanisms of watermelon in response to drought stress and will facilitate watermelon breeding projects to improve drought tolerance. PMID:27861528

  2. Short-term monocular patching boosts the patched eye’s response in visual cortex

    PubMed Central

    Zhou, Jiawei; Baker, Daniel H.; Simard, Mathieu; Saint-Amour, Dave; Hess, Robert F.

    2015-01-01

    Abstract Purpose: Several recent studies have demonstrated that following short-term monocular deprivation in normal adults, the patched eye, rather than the unpatched eye, becomes stronger in subsequent binocular viewing. However, little is known about the site and nature of the underlying processes. In this study, we examine the underlying mechanisms by measuring steady-state visual evoked potentials (SSVEPs) as an index of the neural contrast response in early visual areas. Methods: The experiment consisted of three consecutive stages: a pre-patching EEG recording (14 minutes), a monocular patching stage (2.5 hours) and a post-patching EEG recording (14 minutes; started immediately after the removal of the patch). During the patching stage, a diffuser (transmits light but not pattern) was placed in front of one randomly selected eye. During the EEG recording stage, contrast response functions for each eye were measured. Results: The neural responses from the patched eye increased after the removal of the patch, whilst the responses from the unpatched eye remained the same. Such phenomena occurred under both monocular and dichoptic viewing conditions. Conclusions: We interpret this eye dominance plasticity in adult human visual cortex as homeostatic intrinsic plasticity regulated by an increase of contrast-gain in the patched eye. PMID:26410580

  3. Response of middle atmosphere to short-term solar ultraviolet variations: 2. Theory

    SciTech Connect

    Brasseur, G.; De Rudder, A.; Keating, G.M.; Pitts, M.C.

    1987-01-20

    Ozone and temperature responses to solar variability, based on satellite data, have been reported in a companion paper (Keating et. al., this issue). The present is intended to present a theoretical interpretation of this analysis with the purpose of better understanding the chemical behavior of the stratosphere and the coupling between temperature and ozone concentration, when a periodic forcing is applied to the solar ultraviolet (UV) flux. The response of the temperature and of the trace species concentrations, including ozone, to short-term variations in the solar UV irradiance is calculated by a one-dimensional chemical-radiative time-dependent model. The applied solar variability is assumed to be sinusoidal with a period of 27 days (in accordance with the rotation period of the sun) of 13.5 days (when two active regions are on opposite sides of the sun). The amplitude varies with wavelength, which is consistent with observations made by the Nimbus 7 solar backscattered ultraviolet (SBUV) experiment. The maximum ozone sensitivity in the stratosphere appears to be located near 3 mbar. The calculated amplitude and phase of the ozone response are significantly modified when the feedback between ozone and temperature is taken into account. The ozone/temperature coupling tends to modify the ozone phase lag such that, in the upper stratosphere and in the mesosphere, the ozone peak occurs a few days before the UV peak.

  4. Metabolic and hormonal response to short term fasting after endurance training in the rat.

    PubMed

    Guezennec, C Y; Serrurier, B; Aymonod, M; Merino, D; Pesquies, P C

    1984-11-01

    The metabolic and hormonal response to short term fasting was studied after endurance exercise training. Rats were kept running on a motor driven rodent treadmill 5 days/wk for periods up to 1 h/day for 6 wk. Trained and untrained rats were then fasted for 24 h and 48 h. Liver and muscle glycogen, blood glucose, lactate, beta OH butyrate, glycerol, plasma insulin, testosterone and corticosterone were measured in fed and fasted trained and untrained rats. 48 h fasted trained rats show a lower level of blood lactate (1.08 +/- 0.05 vs 1.33 +/- 0.08 mmol/l-1 of blood glycerol (1 +/- 0.11 vs 0.84 +/- 0.08 mmol/l-1), and of muscle glycogen. There is a significant increase in plasma corticosterone in 48 h fasted trained rats from fed values. Plasma testosterone decreases during fasting, the values are higher in trained rats. Plasma insulin decreases during fasting without any difference between the two groups. These results show higher lipolysis, and decreased glycogenolysis in trained animals during 48 h fasting. The difference between the groups in steroid hormone response could reduce neoglucogenesis and muscle proteolysis in trained animals.

  5. Short-term responses of unicellular planktonic eukaryotes to increases in temperature and UVB radiation

    PubMed Central

    2012-01-01

    Background Small size eukaryotes play a fundamental role in the functioning of coastal ecosystems, however, the way in which these micro-organisms respond to combined effects of water temperature, UVB radiations (UVBR) and nutrient availability is still poorly investigated. Results We coupled molecular tools (18S rRNA gene sequencing and fingerprinting) with microscope-based identification and counting to experimentally investigate the short-term responses of small eukaryotes (<6 μm; from a coastal Mediterranean lagoon) to a warming treatment (+3°C) and UVB radiation increases (+20%) at two different nutrient levels. Interestingly, the increase in temperature resulted in higher pigmented eukaryotes abundances and in community structure changes clearly illustrated by molecular analyses. For most of the phylogenetic groups, some rearrangements occurred at the OTUs level even when their relative proportion (microscope counting) did not change significantly. Temperature explained almost 20% of the total variance of the small eukaryote community structure (while UVB explained only 8.4%). However, complex cumulative effects were detected. Some antagonistic or non additive effects were detected between temperature and nutrients, especially for Dinophyceae and Cryptophyceae. Conclusions This multifactorial experiment highlights the potential impacts, over short time scales, of changing environmental factors on the structure of various functional groups like small primary producers, parasites and saprotrophs which, in response, can modify energy flow in the planktonic food webs. PMID:22966751

  6. Detection of the response of ozone in the middle atmosphere to short-term solar ultraviolet variations

    NASA Astrophysics Data System (ADS)

    Keating, G. M.; Brasseur, G. P.; de Rudder, A.; Nicholson, J. Y., III

    1985-07-01

    The response of ozone to solar UV variation is determined in the middle atmosphere between the heights of 10 and 0.2 mb. The definitive isolation of the smaller variations associated with short-term solar variability is accomplished only after removal of the larger changes of ozone related to temperature variations. Using this approach the correlation coefficients between detrended ozone (Nimbus 7 LIMS) and short-term 205 nm solar variation (Nimbus 7 SBUV) are found to be much higher (0.9) than achieved in previous studies. The theoretical response time and amplitude of response of ozone in the middle atmosphere to observed short-term solar UV variations is found to be in good agreement with observations, except near 0.2 mb. The corresponding long-term response over the solar cycle is also estimated.

  7. Short Term Soil Respiration Response to Fire in a Semi-arid Ecosystem

    NASA Astrophysics Data System (ADS)

    Rozin, A. G.

    2015-12-01

    In the Intermountain West (USA), fire is an important driver of carbon cycling in the environment. Increasing frequency and severity of fires, either through management actions or wildfires, is expected with changing climates in the Western United States. When burning is used as a management tool, it may be beneficial and control the growth of nuisance vegetation, promote the regeneration of grasses and forage species, and reduce hazardous fuel loads to minimize the risk of future wildfires. However, high intensity wildfires often have a negative effect, resulting in a loss of carbon storage and a shift of vegetation communities. This delays recovery of the ecosystem for years or decades and alters the historic fire regime. A 2000 acre prescribed burn in the Reynolds Creek Critical Zone Observatory provided the opportunity to quantify pre and post-burn soil carbon stores and soil carbon losses by heterotrophic respiration. Pre and post-burn soil samples were collected for physical and biogeochemical characterization to quantify substrate availability and possible limitations for heterotrophic respiration. CO2 fluxes were continuously monitored in situ before and immediately after the fire to understand the short-term response of soil respiration to varying burn severities.

  8. Detecting short-term responses to weekend recreation activity: desert bighorn sheep avoidance of hiking trails

    USGS Publications Warehouse

    Longshore, Kathleen; Lowrey, Chris; Thompson, Daniel B.

    2013-01-01

    To study potential effects of recreation activity on habitat use of desert bighorn sheep (Ovis canadensis nelsoni), we placed Global Positioning System collars on 10 female bighorn sheep within the Wonderland of Rocks–Queen Mountain region of Joshua Tree National Park (JOTR), California, USA, from 2002 to 2004. Recreation use was highest from March to April and during weekends throughout the year. Daily use of recreation trails was highest during midday. By comparing habitat use (slope, ruggedness, distance to water, and distance to recreation trails) of female bighorn sheep on weekdays versus weekends, we were able to detect short-term shifts in behavior in response to recreation. In a logistic regression of bighorn sheep locations versus random locations for March and April, female locations at midday (1200 hours) were significantly more distant from recreation trails on weekends compared with weekdays. Our results indicate that within this region of JOTR, moderate to high levels of human recreation activity may temporarily exclude bighorn females from their preferred habitat. However, the relative proximity of females to recreation trails during the weekdays before and after such habitat shifts indicates that these anthropogenic impacts were short-lived. Our results have implications for management of wildlife on public lands where the co-existence of wildlife and recreational use is a major goal.

  9. Negative BOLD response in the hippocampus during short-term spatial memory retrieval.

    PubMed

    Nilsson, Jonna; Ferrier, I Nicol; Coventry, Kenny; Bester, Andre; Finkelmeyer, Andreas

    2013-08-01

    A parieto-medial temporal pathway is thought to underlie spatial navigation in humans. fMRI was used to assess the role of this pathway, including the hippocampus, in the cognitive processes likely to underlie navigation based on environmental cues. Participants completed a short-term spatial memory task in virtual space, which required no navigation but involved the recognition of a target location from a foil location based on environmental landmarks. The results showed that spatial memory retrieval based on environmental landmarks was indeed associated with increased signal in regions of the parieto-medial temporal pathway, including the superior parietal cortex, the retrosplenial cortex, and the lingual gyrus. However, the hippocampus demonstrated a signal decrease below the fixation baseline during landmark-based retrieval, whereas there was no signal change from baseline during retrieval based on viewer position. In a discussion of the origins of such negative BOLD response in the hippocampus, we consider both a suppression of default activity and an increase in activity without a corresponding boost in CBF as possible mechanisms.

  10. Physiological responses to short-term fasting among herbivorous, omnivorous, and carnivorous fishes.

    PubMed

    Day, Ryan D; Tibbetts, Ian R; Secor, Stephen M

    2014-05-01

    We explored the integrated role of dietary specialization and feeding periodicity on the response of the gastrointestinal tract of teleosts fishes to short-term (7-10 days) fasting and refeeding. Fasted and fed herbivorous grass carp (Ctenopharyngodon idella), omnivorous channel catfish (Ictalurus punctatus), and carnivorous largemouth bass (Micropterus salmoides) were compared for digestive organ masses, intestinal morphology, gastrointestinal pH, and the specific activities and total intestinal capacities of the intestinal hydrolases aminopeptidase (APN) and maltase and intestinal nutrient transporters. All three species experience intestinal hypertrophy with feeding as noted by significant increases in enterocyte dimensions. Of the three, only I. punctatus experienced a postprandial increase in intestinal length, and only C. idella experienced significant modulation of intestinal microvillus length. Feeding resulted in acidification of the stomachs of I. punctatus and M. salmoides. Predicted to exhibit a relatively modest set of postprandial responses because of their more frequent feeding habits, C. idella only experienced increases in APN and maltase activity with feeding and no significant regulation of nutrient uptake. Significant regulation of hydrolase activities and nutrient uptake were exhibited by I. punctatus and M. salmoides, with I. punctatus experiencing the most comprehensive set of responses. As predicted by food habits, there was an interspecific gradient in intestinal length and glucose uptake extending from longer intestines and greater glucose uptake for the herbivorous C. idella, intermediate lengths and glucose uptake for the omnivorous I. punctatus, and shorter intestines and reduced glucose uptake for the carnivorous M. salmoides. Among teleosts fishes, short episodes of fasting lead to significant alterations in intestinal form and function that are rapidly restored with feeding.

  11. Short-term responses of wetland vegetation after liming of an Adirondack watershed

    SciTech Connect

    Mackun, I.R.; Leopold, D.J.; Raynal, D.J. )

    1994-08-01

    Watershed liming has been suggested as a long-term mitigation strategy for lake acidity, particularly in areas subject to high levels of acidic deposition. However, virtually no information has been available on the impacts of liming on wetland vegetation. In 1989, 1100 Mg of limestone (83.5% CaCO[sub 3]) were aerially applied to 48% (100 ha) of the Woods Lake watershed in the west-central Adirondack region of New York as part of the first comprehensive watershed liming study in North America. We inventoried wetland vegetation in 1.0-m[sup 2] plots before liming and during the subsequent 2 yr. Within this period liming influenced the cover, frequency, or importance values of only 6 of 64 wetland taxa. The cover of Sphagnum spp. and of the cespitose sedge Carex interior decreased in control relative to limed plots, and cover of the rhizomatous sedge Cladium mariscoides increased nearly threefold in limed areas. These two sedges, which are relatively tall, are characteristic of more calcareous habitats. Cover of the grass Muhlenbergia uniflora, cover and importance were adversely affected or inhibited by lime. It is unclear whether liming directly inhibited the growth of these three small-statured species, or whether the adverse effects of lime were mediated through shifts in competitive interactions with other species. The limited responses that we observed to liming, along with changes that occurred in control plots over the study period, may indicate that in the short term watershed liming was no more of a perturbation than the environmental factors responsible for natural annual variation in wetland communities.

  12. Regional differences in sweat rate response of steers to short-term heat stress

    NASA Astrophysics Data System (ADS)

    Scharf, B.; Wax, L. E.; Aiken, G. E.; Spiers, D. E.

    2008-11-01

    Six Angus steers (319 ± 8.5 kg) were assigned to one of two groups (hot or cold exposure) of three steers each, and placed into two environmental chambers initially maintained at 16.5-18.8°C air temperature ( T a). Cold chamber T a was lowered to 8.4°C, while T a within the hot chamber was increased to 32.7°C over a 24-h time period. Measurements included respiration rate, and air and body (rectal and skin) temperatures. Skin temperature was measured at shoulder and rump locations, with determination of sweat rate using a calibrated moisture sensor. Rectal temperature did not change in cold or hot chambers. However, respiration rate nearly doubled in the heat ( P < 0.05), increasing when T a was above 24°C. Skin temperatures at the two locations were highly correlated ( P < 0.05) with each other and with T a. In contrast, sweat rate showed differences at rump and shoulder sites. Sweat rate of the rump exhibited only a small increase with T a. However, sweat rate at the shoulder increased more than four-fold with increasing T a. Increased sweat rate in this region is supported by an earlier report of a higher density of sweat glands in the shoulder compared to rump regions. Sweat rate was correlated with several thermal measurements to determine the best predictor. Fourth-order polynomial expressions of short-term rectal and skin temperature responses to hot and cold exposures produced r values of 0.60, 0.84, and 0.98, respectively. These results suggest that thermal inputs other than just rectal or skin temperature drive the sweat response in cattle.

  13. Regional differences in sweat rate response of steers to short-term heat stress.

    PubMed

    Scharf, B; Wax, L E; Aiken, G E; Spiers, D E

    2008-11-01

    Six Angus steers (319 +/- 8.5 kg) were assigned to one of two groups (hot or cold exposure) of three steers each, and placed into two environmental chambers initially maintained at 16.5-18.8 degrees C air temperature (Ta). Cold chamber Ta was lowered to 8.4 degrees C, while Ta within the hot chamber was increased to 32.7 degrees C over a 24-h time period. Measurements included respiration rate, and air and body (rectal and skin) temperatures. Skin temperature was measured at shoulder and rump locations, with determination of sweat rate using a calibrated moisture sensor. Rectal temperature did not change in cold or hot chambers. However, respiration rate nearly doubled in the heat (P < 0.05), increasing when Ta was above 24 degrees C. Skin temperatures at the two locations were highly correlated (P < 0.05) with each other and with Ta. In contrast, sweat rate showed differences at rump and shoulder sites. Sweat rate of the rump exhibited only a small increase with Ta. However, sweat rate at the shoulder increased more than four-fold with increasing Ta. Increased sweat rate in this region is supported by an earlier report of a higher density of sweat glands in the shoulder compared to rump regions. Sweat rate was correlated with several thermal measurements to determine the best predictor. Fourth-order polynomial expressions of short-term rectal and skin temperature responses to hot and cold exposures produced r values of 0.60, 0.84, and 0.98, respectively. These results suggest that thermal inputs other than just rectal or skin temperature drive the sweat response in cattle.

  14. P3 response during short-term memory retrieval revisited by a spatio-temporal analysis.

    PubMed

    Ergen, Mehmet; Yildirim, Erol; Uslu, Atilla; Gürvit, Hakan; Demiralp, Tamer

    2012-05-01

    The most reported event related potential (ERP) parameter during short-term memory retrieval has been P3 wave and the association has been built on the relation between P3 latency and reaction times. The aim of this study is to identify an ERP component that reflects the memory scanning process preceding the decision making stage which has been associated with the P3 peak. A spatiotemporal analysis was applied on the P3 and pre-P3 period of ERP responses obtained during the retrieval phase of the Sternberg paradigm with two memory load conditions (3 and 5 letters in the memory set). In the easy task condition with the fastest reaction times (positive probes of 3 letters condition), a single P3 was observed, whereas P3 was split into two peaks in responses to probe items of more demanding task conditions. The single P3 peak and the later components of the split P3 peaks displayed the typical P3 topography. On the other hand, the topographic mapping of the earlier peak of the split P3 wave and ascending part of the single P3 peak revealed a right parietal topography. The onset time of this earlier right lateralized topography was stable among all conditions but it persisted longer in the high memory load condition. We conclude that the right-lateralized positivity in the pre-P3 period reflects the memory scanning process followed by the P3 peak with midline parietal topography reflecting the decision making process.

  15. Brain tumor vessel response to synchrotron microbeam radiation therapy: a short-term in vivo study

    NASA Astrophysics Data System (ADS)

    Serduc, Raphaël; Christen, Thomas; Laissue, Jean; Farion, Régine; Bouchet, Audrey; van der Sanden, Boudewijn; Segebarth, Christoph; Bräuer-Krisch, Elke; LeDuc, Géraldine; Bravin, Alberto; Rémy, Chantal; Barbier, Emmanuel L.

    2008-07-01

    The aim of this work focuses on the description of the short-term response of a 9L brain tumor model and its vasculature to microbeam radiation therapy (MRT) using magnetic resonance imaging (MRI). Rat 9L gliosarcomas implanted in nude mice brains were irradiated by MRT 13 days after tumor inoculation using two orthogonal arrays of equally spaced 28 planar microbeams (25 µm width, 211 µm spacing and dose 500 Gy). At 1, 7 and 14 days after MRT, apparent diffusion coefficient, blood volume and vessel size index were mapped by MRI. Mean survival time after tumor inoculation increased significantly between MRT-treated and untreated groups (23 and 28 days respectively, log-rank test, p < 0.0001). A significant increase of apparent diffusion coefficient was observed 24 h after MRT in irradiated tumors versus non-irradiated ones. In the untreated group, both tumor size and vessel size index increased significantly (from 7.6 ± 2.2 to 19.2 ± 4.0 mm2 and +23%, respectively) between the 14th and the 21st day after tumor cell inoculation. During the same period, in the MRT-treated group, no difference in tumor size was observed. The vessel size index measured in the MRT-treated group increased significantly (+26%) between 14 and 28 days of tumor growth. We did not observe the significant difference in blood volume between the MRT-treated and untreated groups. MRT slows 9L tumor growth in a mouse brain but MRI results suggest that the increase in survival time after our MRT approach may be rather due to a cytoreduction than to early direct effects of ionizing radiation on tumor vessels. These results suggest that MRT parameters need to be optimized to further damage tumor vessels.

  16. Short term modulation of trunk neuromuscular responses following spinal manipulation: a control group study

    PubMed Central

    2013-01-01

    Background Low back pain (LBP) is one of the most frequent musculoskeletal conditions in industrialized countries and its economic impact is important. Spinal manipulation therapy (SMT) is believed to be a valid approach in the treatment of both acute and chronic LBP. It has also been shown that SMT can modulate the electromyographic (EMG) activity of the paraspinal muscle. The purpose of this study was to investigate, in a group of patients with low back pain, the persistence of changes observed in trunk neuromuscular responses after a spinal manipulation (SMT). Methods Sixty adult participants with LBP performed a block of 5 flexion-extension movements. Participants in the experimental group (n=30) received lumbar SMT whereas participants in the control group (n=30) were positioned similarly for the treatment but did not receive SMT. Blocks of flexion-extension movements were repeated immediately after the manipulation as well as 5 and 30 minutes after SMT (or control position). EMG activity of paraspinal muscles was recorded at L2 and L5 level and kinematic data were collected to evaluate the lumbo-pelvic kinematics. Pain intensity was noted after each block. Normalized EMG, pain intensity and lumbo-pelvic kinematics were compared across experimental conditions. Results Participants from the control group showed a significant increase in EMG activity during the last block (30 min) of flexion-extension trials in both flexion and full-flexion phases at L2. Increase in VAS scores was also observed in the last 2 blocks (5 min and 30 min) in the control group. No significant group x time interaction was seen at L5. No significant difference was observed in the lumbo-pelvic kinematics. Conclusion Changes in trunk neuromuscular control following HVLA spinal manipulation may reduce sensitization or muscle fatigue effects related to repetitive movement. Future studies should investigate short term changes in neuromuscular components, tissue properties and clinical

  17. Responses of pond-breeding amphibians to wildfire: Short-term patterns in occupancy and colonization

    USGS Publications Warehouse

    Hossack, B.R.; Corn, P.S.

    2007-01-01

    Wildland fires are expected to become more frequent and severe in many ecosystems, potentially posing a threat to many sensitive species. We evaluated the effects of a large, stand-replacement wildfire on three species of pond-breeding amphibians by estimating changes in occupancy of breeding sites during the three years before and after the fire burned 42 of 83 previously surveyed wetlands. Annual occupancy and colonization for each species was estimated using recently developed models that incorporate detection probabilities to provide unbiased parameter estimates. We did not find negative effects of the fire on the occupancy or colonization rates of the long-toed salamander (Ambystoma macrodactylum). Instead, its occupancy was higher across the study area after the fire, possibly in response to a large snowpack that may have facilitated colonization of unoccupied wetlands. Naïve data (uncorrected for detection probability) for the Columbia spotted frog (Rana luteiventris) initially led to the conclusion of increased occupancy and colonization in wetlands that burned. After accounting for temporal and spatial variation in detection probabilities, however, it was evident that these parameters were relatively stable in both areas before and after the fire. We found a similar discrepancy between naïve and estimated occupancy of A. macrodactylum that resulted from different detection probabilities in burned and control wetlands. The boreal toad (Bufo boreas) was not found breeding in the area prior to the fire but colonized several wetlands the year after they burned. Occupancy by B. boreas then declined during years 2 and 3 following the fire. Our study suggests that the amphibian populations we studied are resistant to wildfire and that B. boreas may experience short-term benefits from wildfire. Our data also illustrate how naïve presence–non-detection data can provide misleading results.

  18. Attentional Demands Predict Short-Term Memory Load Response in Posterior Parietal Cortex

    ERIC Educational Resources Information Center

    Magen, Hagit; Emmanouil, Tatiana-Aloi; McMains, Stephanie A.; Kastner, Sabine; Treisman, Anne

    2009-01-01

    Limits to the capacity of visual short-term memory (VSTM) indicate a maximum storage of only 3 or 4 items. Recently, it has been suggested that activity in a specific part of the brain, the posterior parietal cortex (PPC), is correlated with behavioral estimates of VSTM capacity and might reflect a capacity-limited store. In three experiments that…

  19. CHARACTERIZATION OF RESPONSES TO THE ANTIANDROGEN FLUTAMIDE IN A SHORT-TERM REPRODUCTION ASSAY WITH THE FATHEAD MINNOW

    EPA Science Inventory

    A short-term reproduction assay with the fathead minnow has been developed to detect chemicals with the potential to disrupt reproductive endocrine functions controlled by estrogen- and androgen-mediated pathways. The objective of this study was to characterize the responses of t...

  20. Characterization of miRNAs in response to short-term waterlogging in three inbred lines of Zea mays

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To characterize the involvement of miRNAs and their targets in response to short-term hypoxia conditions, a quantitative real time PCR (qRT-PCR) assay was used to quantify the expression of the 24 candidate mature miRNA signatures (22 known and 2 novel mature miRNAs, representing 66 miRNA loci) and ...

  1. Determinants of erythropoietin release in response to short-term hypobaric hypoxia

    NASA Technical Reports Server (NTRS)

    Ge, Ri-Li; Witkowski, S.; Zhang, Y.; Alfrey, C.; Sivieri, M.; Karlsen, T.; Resaland, G. K.; Harber, M.; Stray-Gundersen, J.; Levine, B. D.

    2002-01-01

    We measured blood erythropoietin (EPO) concentration, arterial O(2) saturation (Sa(O(2))), and urine PO(2) in 48 subjects (32 men and 16 women) at sea level and after 6 and 24 h at simulated altitudes of 1,780, 2,085, 2,454, and 2,800 m. Renal blood flow (Doppler) and Hb were determined at sea level and after 6 h at each altitude (n = 24) to calculate renal O(2) delivery. EPO increased significantly after 6 h at all altitudes and continued to increase after 24 h at 2,454 and 2,800 m, although not at 1,780 or 2,085 m. The increase in EPO varied markedly among individuals, ranging from -41 to 400% after 24 h at 2,800 m. Similar to EPO, urine PO(2) decreased after 6 h at all altitudes and returned to baseline by 24 h at the two lowest altitudes but remained decreased at the two highest altitudes. Urine PO(2) was closely related to EPO via a curvilinear relationship (r(2) = 0.99), although also with prominent individual variability. Renal blood flow remained unchanged at all altitudes. Sa(O(2)) decreased slightly after 6 h at the lowest altitudes but decreased more prominently at the highest altitudes. There were only modest, albeit statistically significant, relationships between EPO and Sa(O(2)) (r = 0.41, P < 0.05) and no significant relationship with renal O(2) delivery. These data suggest that 1) the altitude-induced increase in EPO is "dose" dependent: altitudes > or =2,100-2,500 m appear to be a threshold for stimulating sustained EPO release in most subjects; 2) short-term acclimatization may restore renal tissue oxygenation and restrain the rise in EPO at the lowest altitudes; and 3) there is marked individual variability in the erythropoietic response to altitude that is only partially explained by "upstream" physiological factors such as those reflecting O(2) delivery to EPO-producing tissues.

  2. Historical peat loss explains limited short-term response of drained blanket bogs to rewetting.

    PubMed

    Williamson, Jennifer; Rowe, Edwin; Reed, David; Ruffino, Lucia; Jones, Peter; Dolan, Rachel; Buckingham, Helen; Norris, David; Astbury, Shaun; Evans, Chris D

    2017-03-01

    This study assessed the short-term impacts of ditch blocking on water table depth and vegetation community structure in a historically drained blanket bog. A chronosequence approach was used to compare vegetation near ditches blocked 5 years, 4 years and 1 year prior to the study with vegetation near unblocked ditches. Plots adjacent to and 3 m away from 70 ditches within an area of blanket bog were assessed for floristic composition, aeration depth using steel bars, and topography using LiDAR data. No changes in aeration depth or vegetation parameters were detected as a function of ditch-blocking, time since blocking, or distance from the ditch, with the exception of non-Sphagnum bryophytes which had lower cover in quadrats adjacent to ditches that had been blocked for 5 years. Analysis of LiDAR data and the observed proximity of the water table to the peat surface led us to conclude that the subdued ecosystem responses to ditch-blocking were the result of historical peat subsidence within a 4-5 m zone either side of each ditch, which had effectively lowered the peat surface to the new, ditch-influenced water table. We estimate that this process led to the loss of around 500,000 m(3) peat within the 38 km(2) study area following drainage, due to a combination of oxidation and compaction. Assuming that 50% of the volume loss was due to oxidation, this amounts to a carbon loss of 11,000 Mg C over this area, i.e. 3 Mg C ha(-1). The apparent 'self-rewetting' of blanket bogs in the decades following drainage has implications for their restoration as it suggests that there may not be large quantities of dry peat left to rewet, and that there is a risk of inundation (potentially leading to high methane emissions) along subsided ditch lines. Many peatland processes are likely to be maintained in drained blanket bog, including support of typical peatland vegetation, but infilling of lost peat and recovery of original C stocks are likely to take longer than is

  3. Short term response of a peatland to warming and drought - climate manipulation experiment in W Poland

    NASA Astrophysics Data System (ADS)

    Juszczak, Radosław; Chojnicki, Bogdan; Urbaniak, Marek; Leśny, Jacek; Silvennoinen, Hanna; Lamentowicz, Mariusz; Basińska, Anna; Gąbka, Maciej; Stróżecki, Marcin; Samson, Mateusz; Łuców, Dominika; Józefczyk, Damian; Hoffmann, Mathias; Olejnik, Janusz

    2016-04-01

    conditions led to increases in NDVI and LAI, whilst the site exposed to only drought exhibited the lowest LAI. Warming shifted the vegetation species composition by promoting vascular plants (mainly Carex rostrata and C. limosa), which result also correlates positively with nutrient (Ptot, Mn, F, Na, Zn) availability in the peat water. Here, we report short-term responses to increased temperature and diminished precipitation, showing that the combination of these to stressors leads to very different scenario than their individual impacts. Our results further emphasize the need for long term records from field manipulation site on peatland response to climate changes. The Research was co-founded by the Polish National Centre for Research and Development within the Polish-Norwegian Research Programme within the WETMAN project (Central European Wetland Ecosystem Feedbacks to Changing Climate - Field Scale Manipulation, Project ID: 203258, contract No. Pol-Nor/203258/31/2013 (www.wetman.pl). References Fenner N., Freeman Ch. (2011). Nature Geoscience, 4, 895-900 Hoffmann M., et al. (2015). Agricultural and Forest Meteorology, 200, 30-45 Kimball BA. (2005). Global Change Biology, 11, 2041-2056

  4. HPA axis response to stress predicts short-term snack intake in obese women.

    PubMed

    Appelhans, Bradley M; Pagoto, Sherry L; Peters, Erica N; Spring, Bonnie J

    2010-02-01

    Prior research has linked heightened cortisol reactivity to stress with increased food consumption. This pilot study tested corollaries of the hypothesis that cortisol stress reactivity promotes obesity. Thirty-four lean and obese women completed an acute stress task and a non-stressful control task in counterbalanced order. Contrary to expectations, higher post-stress cortisol was associated with decreased post-stress snack intake in obese women but was unrelated to snack intake in lean women. Stress also blunted an expected rise in hunger only among obese women. Findings suggest that some obese women may be more sensitive to short-term anorectic effects of HPA axis activation.

  5. Characterization of miRNAs in response to short-term waterlogging in three inbred lines of Zea mays.

    PubMed

    Liu, Zhijie; Kumari, Sunita; Zhang, Lifang; Zheng, Yonglian; Ware, Doreen

    2012-01-01

    Waterlogging of plants leads to low oxygen levels (hypoxia) in the roots and causes a metabolic switch from aerobic respiration to anaerobic fermentation that results in rapid changes in gene transcription and protein synthesis. Our research seeks to characterize the microRNA-mediated gene regulatory networks associated with short-term waterlogging. MicroRNAs (miRNAs) are small non-coding RNAs that regulate many genes involved in growth, development and various biotic and abiotic stress responses. To characterize the involvement of miRNAs and their targets in response to short-term hypoxia conditions, a quantitative real time PCR (qRT-PCR) assay was used to quantify the expression of the 24 candidate mature miRNA signatures (22 known and 2 novel mature miRNAs, representing 66 miRNA loci) and their 92 predicted targets in three inbred Zea mays lines (waterlogging tolerant Hz32, mid-tolerant B73, and sensitive Mo17). Based on our studies, miR159, miR164, miR167, miR393, miR408 and miR528, which are mainly involved in root development and stress responses, were found to be key regulators in the post-transcriptional regulatory mechanisms under short-term waterlogging conditions in three inbred lines. Further, computational approaches were used to predict the stress and development related cis-regulatory elements on the promoters of these miRNAs; and a probable miRNA-mediated gene regulatory network in response to short-term waterlogging stress was constructed. The differential expression patterns of miRNAs and their targets in these three inbred lines suggest that the miRNAs are active participants in the signal transduction at the early stage of hypoxia conditions via a gene regulatory network; and crosstalk occurs between different biochemical pathways.

  6. Modeling the action-potential-sensitive nonlinear-optical response of myelinated nerve fibers and short-term memory

    NASA Astrophysics Data System (ADS)

    Shneider, M. N.; Voronin, A. A.; Zheltikov, A. M.

    2011-11-01

    The Goldman-Albus treatment of the action-potential dynamics is combined with a phenomenological description of molecular hyperpolarizabilities into a closed-form model of the action-potential-sensitive second-harmonic response of myelinated nerve fibers with nodes of Ranvier. This response is shown to be sensitive to nerve demyelination, thus enabling an optical diagnosis of various demyelinating diseases, including multiple sclerosis. The model is applied to examine the nonlinear-optical response of a three-neuron reverberating circuit—the basic element of short-term memory.

  7. Short-term response of Dicamptodon tenebrosus larvae to timber management in southwestern Oregon

    USGS Publications Warehouse

    Leuthold, N.; Adams, M.J.; Hayes, J.P.

    2012-01-01

    In the Pacific Northwest, previous studies have found a negative effect of timber management on the abundance of stream amphibians, but results have been variable and region specific. These studies have generally used survey methods that did not account for differences in capture probability and focused on stands that were harvested under older management practices. We examined the influences of contemporary forest practices on larval Dicamptodon tenebrosus as part of the Hinkle Creek paired watershed study. We used a mark-recapture analysis to estimate D. tenebrosus density at 100 1-m sites spread throughout the basin and used extended linear models that accounted for correlation resulting from the repeated surveys at sites across years. Density was associated with substrate, but we found no evidence of an effect of harvest. While holding other factors constant, the model-averaged estimates indicated; 1) each 10% increase in small cobble or larger substrate increased median density of D. tenebrosus 1.05 times, 2) each 100-ha increase in the upstream area drained decreased median density of D. tenebrosus 0.96 times, and 3) increasing the fish density in the 40 m around a site by 0.01 increased median salamander density 1.01 times. Although this study took place in a single basin, it suggests that timber management in similar third-order basins of the southwestern Oregon Cascade foothills is unlikely to have short-term effects of D. tenebrosus larvae. ?? 2011 The Wildlife Society. Copyright ?? The Wildlife Society, 2011.

  8. Short-term response of (Dicamptodon tenebrosus) larvae to timber management in southwestern Oregon

    USGS Publications Warehouse

    Leuthold, Niels; Adams, Michael J.; Hayes, John P.

    2012-01-01

    In the Pacific Northwest, previous studies have found a negative effect of timber management on the abundance of stream amphibians, but results have been variable and region specific. These studies have generally used survey methods that did not account for differences in capture probability and focused on stands that were harvested under older management practices. We examined the influences of contemporary forest practices on larval Dicamptodon tenebrosus as part of the Hinkle Creek paired watershed study. We used a mark–recapture analysis to estimate D. tenebrosus density at 100 1-m sites spread throughout the basin and used extended linear models that accounted for correlation resulting from the repeated surveys at sites across years. Density was associated with substrate, but we found no evidence of an effect of harvest. While holding other factors constant, the model-averaged estimates indicated; 1) each 10% increase in small cobble or larger substrate increased median density of D. tenebrosus 1.05 times, 2) each 100-ha increase in the upstream area drained decreased median density of D. tenebrosus 0.96 times, and 3) increasing the fish density in the 40 m around a site by 0.01 increased median salamander density 1.01 times. Although this study took place in a single basin, it suggests that timber management in similar third-order basins of the southwestern Oregon Cascade foothills is unlikely to have short-term effects of D. tenebrosus larvae.

  9. Skeletal muscle proteolysis in response to short-term unloading in humans

    PubMed Central

    Tesch, Per A.; von Walden, Ferdinand; Gustafsson, Thomas; Linnehan, Richard M.; Trappe, Todd A.

    2008-01-01

    Skeletal muscle atrophy is evident after muscle disuse, unloading, or spaceflight and results from decreased protein content as a consequence of decreased protein synthesis, increased protein breakdown or both. At this time, there are essentially no human data describing proteolysis in skeletal muscle undergoing atrophy on Earth or in space, primarily due to lack of valid and accurate methodology. This particular study aimed at assessing the effects of short-term unloading on the muscle contractile proteolysis rate. Eight men were subjected to 72-h unilateral lower limb suspension (ULLS) and intramuscular interstitial levels of the naturally occurring proteolytic tracer 3-methylhistidine (3MH) were measured by means of microdialysis before and on completion of this intervention. The 3MH concentration following 72-h ULLS (2.01 ± 0.22 nmol/ml) was 44% higher (P < 0.05) than before ULLS (1.56 ± 0.20 nmol/ml). The present experimental model and the employed method determining 3MH in microdialysates present a promising tool for monitoring skeletal muscle proteolysis or metabolism of specific muscles during conditions resulting in atrophy caused by, e.g., disuse and real or simulated microgravity. This study provides evidence that the atrophic processes are evoked rapidly and within 72 h of unloading and suggests that countermeasures should be employed in the early stages of space missions to offset or prevent muscle loss during the period when the rate of muscle atrophy is the highest. PMID:18535133

  10. Short-term response of Dicamptodon tenebrosus larvae to timber management in southwestern Oregon

    USGS Publications Warehouse

    Leuthold, Niels; Adams, Michael J.; Hayes, John P.

    2012-01-01

    In the Pacific Northwest, previous studies have found a negative effect of timber management on the abundance of stream amphibians, but results have been variable and region specific. These studies have generally used survey methods that did not account for differences in capture probability and focused on stands that were harvested under older management practices. We examined the influences of contemporary forest practices on larval Dicamptodon tenebrosus as part of the Hinkle Creek paired watershed study. We used a mark-recapture analysis to estimate D. tenebrosus density at 100 1-m sites spread throughout the basin and used extended linear models that accounted for correlation resulting from the repeated surveys at sites across years. Density was associated with substrate, but we found no evidence of an effect of harvest. While holding other factors constant, the model-averaged estimates indicated; 1) each 10% increase in small cobble or larger substrate increased median density of D. tenebrosus 1.05 times, 2) each 100-ha increase in the upstream area drained decreased median density of D. tenebrosus 0.96 times, and 3) increasing the fish density in the 40 m around a site by 0.01 increased median salamander density 1.01 times. Although this study took place in a single basin, it suggests that timber management in similar third-order basins of the southwestern Oregon Cascade foothills is unlikely to have short-term effects of D. tenebrosus larvae.

  11. Validation of the HIV Tropism Test TROCAI Using the Virological Response to a Short-Term Maraviroc Monotherapy Exposure

    PubMed Central

    Genebat, M.; De Luna-Romero, M.; Tarancon-Diez, L.; Dominguez-Molina, B.; Pacheco, Y. M.; Muñoz-Fernández, M. A.; Leal, M.

    2016-01-01

    TROCAI is a phenotypic tropism test developed using the virological response to a short-term exposure to maraviroc monotherapy (Maraviroc Clinical Test [MCT]). It was found that with TROCAI, a cutoff of <0.5% of dual/mixed viruses was needed to predict R5 HIV tropism. Here, we have validated TROCAI, using this cutoff, in a new cohort of 42 patients, finding a very high concordance between TROCAI and MCT (98%), and a good concordance (71 to 87%) with other genotypic/phenotypic methods. PMID:27480849

  12. Effect of short-term intralipid infusion on the immune response during low-dose endotoxemia in humans.

    PubMed

    Krogh-Madsen, Rikke; Plomgaard, Peter; Akerstrom, Thorbjorn; Møller, Kirsten; Schmitz, Ole; Pedersen, Bente Klarlund

    2008-02-01

    Novel anti-inflammatory effects of insulin have recently been described, and insulin therapy to maintain euglycemia suppresses the plasma levels of free fatty acids (FFA) and increases the survival of critically ill patients. We aimed to explore the effect of short-term high levels of plasma FFA on the inflammatory response to a low dose of endotoxin. Fourteen healthy male volunteers underwent the following two trials in a randomized crossover design: 1) continuous infusion of 20% Intralipid [0.7 ml.kg(-1).h(-1) (1.54 g/kg)] for 11 h, and 2) infusion of isotonic saline for 11 h (control). In each trial, heparin was given to activate lipoprotein lipase, and an intravenous bolus of endotoxin (0.1 ng/kg) was given after 6 h of Intralipid/saline infusion. Blood samples and muscle and fat biopsies were obtained before the Intralipid/saline infusion and before as well as after infusion of an endotoxin bolus. Plasma levels of FFA, triglycerides, and glycerol were markedly increased during the Intralipid infusion. Endotoxin exposure induced an increase in plasma levels of TNF-alpha, IL-6, and neutrophils and further stimulated gene expression of TNF-alpha and IL-6 in both skeletal muscle and adipose tissue. The systemic inflammatory response to endotoxin was significantly pronounced during Intralipid infusion. Short-term hyperlipidemia enhances the inflammatory response to endotoxin, and skeletal muscle and adipose tissue are capable of producing essential inflammatory mediators after endotoxin stimulation.

  13. Nonverbal communication sets the conditions for the relationship between parental bonding and the short-term treatment response in depression.

    PubMed

    Geerts, Erwin; van Os, Titus; Gerlsma, Coby

    2009-01-30

    The role of parental bonding and nonverbal communication in the short-term treatment response was investigated in 104 depressed outpatients. At baseline patients completed the Parental Bonding Instrument. We registered the nonverbal involvement behaviour of patients and interviewers from video recordings of baseline clinical interviews and calculated the convergence between patient-interviewer behaviour over the interview. The course of depression was assessed with the Beck Depression Inventory. As hypothesized, low maternal care and high paternal overprotection predicted a poor response to an 8-week treatment. Maternal care was positively correlated with nonverbal convergence. Moreover, convergence moderated the relationship between maternal care and the response to treatment: Lack of convergence between patients and interviewers turned out to annul the positive effects of maternal care on the treatment response. The findings link theories on early parenting to interpersonal theories of depression.

  14. Physiological and production responses to feeding schedule in lactating dairy cows exposed to short-term, moderate heat stress.

    PubMed

    Ominski, K H; Kennedy, A D; Wittenberg, K M; Moshtaghi Nia, S A

    2002-04-01

    The objective of this research was to characterize the production responses of lactating dairy cows during and after short-term, moderate heat exposure, and to determine whether evening (p.m.) feeding would alleviate the associated production losses. In a two-period, cross-over design, eight mature lactating cows were fed a total mixed ration at either 0830 or 2030 h. Each 15-d period consisted of a 5-d thermoneutral phase, a 5-d heat stress phase and a 5-d thermoneutral recovery phase. Mean daily vaginal temperature and respiration rate increased by 0.6 +/- 0.04 degrees C and 27 +/- 1.3 breaths/min, respectively, during short-term heat exposure. Daily dry matter intake, milk yield and solids-not-fat were depressed by 1.4 +/- 0.13 kg, 1.7 +/- 0.32 kg and 0.07 +/- 0.023%, respectively, during heat exposure. During the recovery phase, dry matter intake remained depressed, milk protein declined by 0.05 +/- 0.020%, and daily milk yield exhibited a further decline of 1.2 +/- 0.32 kg. Time of feeding had no effect on vaginal temperature, respiration rate, dry matter intake, water intake, milk yield, fat-corrected milk, protein percent, solids-non-fat percent or somatic cell count during heat exposure or during the recovery period that followed. Fat percent was, however, significantly lower in p.m.-fed animals. These data indicate that short-term, moderate heat stress, which occurs during the spring and summer months in Canada and the Northern United States, will significantly decrease production in the lactating cow. Shifting from morning to evening feeding did not alleviate production losses associated with this type of heat stress.

  15. Extending food deprivation reverses the short-term lipolytic response to fasting: role of the triacylglycerol/fatty acid cycle.

    PubMed

    Weber, Jean-Michel; Reidy, Shannon P

    2012-05-01

    The effects of short-term food deprivation on lipid metabolism are well documented, but little is known about prolonged fasting. This study monitored the kinetics of glycerol (rate of appearance, R(a) glycerol) and non-esterified fatty acids (R(a) NEFA) in fasting rabbits. Our goals were to determine whether lipolysis is stimulated beyond values seen for short-term fasting, and to characterize the roles of primary (intracellular) and secondary (with transit through the circulation) triacylglycerol/fatty acid cycling (TAG/FA cycling) in regulating fatty acid allocation to oxidation or re-esterification. R(a) glycerol (9.62±0.72 to 15.29±0.96 μmol kg(-1) min(-1)) and R(a) NEFA (18.05±2.55 to 31.25±1.93 μmol kg(-1) min(-1)) were stimulated during the first 2 days of fasting, but returned to baseline after 4 days. An initial increase in TAG/FA cycling was followed by a reduction below baseline after 6 days without food, with primary and secondary cycling contributing to these responses. We conclude that the classic activation of lipolysis caused by short-term fasting is abolished when food deprivation is prolonged. High rates of re-esterification may become impossible to sustain, and TAG/FA cycling could decrease to reduce its cost to 3% of total energy expenditure. Throughout prolonged fasting, fatty acid metabolism gradually shifts towards increased oxidation and reduced re-esterification. Survival is achieved by pressing fuel selection towards the fatty acid dominance of energy metabolism and by slowing substrate cycles to assist metabolic suppression. However, TAG/FA cycling remains active even after prolonged fasting, suggesting that re-esterification is a crucial mechanism that cannot be stopped without harmful consequences.

  16. Short-term time course of liver metabolic response to acute handling stress in rainbow trout, Oncorhynchus mykiss.

    PubMed

    López-Patiño, Marcos A; Hernández-Pérez, Juan; Gesto, Manuel; Librán-Pérez, Marta; Míguez, Jesús M; Soengas, José L

    2014-02-01

    To elucidate the short-term time-course of liver metabolic response in rainbow trout to acute handling stress we subjected rainbow trout to 5min chasing and obtained samples 0 to 480min post-stress. Levels of cortisol, glucose and lactate were measured in plasma, whereas metabolite levels, enzyme activities, mRNA abundance of parameters related to energy metabolism, and glucocorticoid receptors were assessed in liver. Acute stress affected many parameters related to energy metabolism, with most of them turning back to normal levels after 480min. In general, the present results support the existence of two stages in the short-term time-course of metabolic response to handling stress. A first stage occurring few minutes post-stress (15-45min), was characterized by increased mobilization of liver glycogen resulting in increased production of endogenous glucose, reduced use of exogenous glucose and reduced lipogenic potential. A second stage, occurring 60-120min post-stress onwards was characterized by the recovery of liver glycogen levels, the increased capacity of liver for releasing glucose, and the recovery of lipogenic capacity whereas no changes were noted in gluconeogenic potential, which probably needs longer time periods to become enhanced.

  17. Development of Short Term Immunotoxicological Assays for Prediction of Chronic Toxicological Responses Induced by Environmental Chemicals

    DTIC Science & Technology

    1986-11-25

    dexamethasone, M,~ synthesis , humoral immunity, inmmunotoxicolov,,, mouqe, Lrichloroethvtlene, mixed lymphocytr! reaction, * rye lophosphamide, microsor~al...over the exposure period. Als in this tier was the effect of chemicals on DNA synthesis . For Tier 2, the "lymphocyte response to a T and a B cell...Cell DNA Synthesis ....... .................. 13 Spleen Cell Response to Mitvgens (Tier 2). . . .. ........ 20 Spleen Cell Response to Concanavalin A

  18. Processing Demand and Short-Term Memory: The Response-Prefix Effect

    ERIC Educational Resources Information Center

    Jahnke, John C.; Nowaczyk, Ronald H.

    1977-01-01

    Seven-digit strings were presented for immediate recall. Before recall, subjects either read or retrieved from memory a single item (response prefix). Results were seen in terms of the sharing of the limited capacity of an active memory system by the memory series, the response prefix, and the operations to retrieve and emit the items. (Editor/RK)

  19. Short-Term Forecasting of Inertial Response from a Wind Power Plant: Preprint

    SciTech Connect

    Muljadi, Eduard; Gevorgian, Vahan; Hoke, Andy

    2016-09-01

    The total inertia stored in all rotating masses (synchronous generators, induction motors, etc.) connected to a power system grid is an essential force that keeps the system stable after disturbances. Power systems have been experiencing reduced inertia during the past few decades [1]. This trend will continue as the level of renewable generation (e.g., wind and solar) increases. Wind power plants (WPPs) and other renewable power plants with power electronic interfaces are capable of delivering frequency response (both droop and/or inertial response) by a control action; thus, the reduction in available online inertia can be compensated by designing the plant control to include frequency response. The source of energy to be delivered as inertial response is determined by the type of generation (wind, photovoltaic, concentrating solar power, etc.) and the control strategy chosen. The importance of providing ancillary services to ensure frequency control within a power system is evidenced from many recent publications with different perspectives (manufacturer, system operator, regulator, etc.) [2]-[6]. This paper is intended to provide operators with a method for the real-time assessment of the available inertia of a WPP. This is critical to managing power system stability and the reserve margin. In many states, modern WPPs are required to provide ancillary services (e.g., frequency regulation via governor response and inertial response) to the grid. This paper describes the method of estimating the available inertia and the profile of the forecasted response from a WPP.

  20. Inherent insulin sensitivity is a major determinant of multimeric adiponectin responsiveness to short-term weight loss in extreme obesity.

    PubMed

    Mai, Stefania; Walker, Gillian E; Brunani, Amelia; Guzzaloni, Gabriele; Grossi, Glenda; Oldani, Alberto; Aimaretti, Gianluca; Scacchi, Massimo; Marzullo, Paolo

    2014-07-24

    High molecular weight (HMW-A) adiponectin levels mirror alterations in glucose homeostasis better than medium (MMW-A) and low molecular weight (LMW-A) components. In 25 patients with wide-range extreme obesity (BMI 40-77 kg/m(2)), we aimed to explore if improvements of multimeric adiponectin following 4-wk weight loss reflect baseline OGTT-derived insulin sensitivity (ISIOGTT) and disposition index (DIOGTT). Compared to 40 lean controls, adiponectin oligomers were lower in extreme obesity (p < 0.001) and, within this group, HMW-A levels were higher in insulin-sensitive (p < 0.05) than -resistant patients. In obese patients, short-term weight loss did not change total adiponectin levels and insulin resistance, while the distribution pattern of adiponectin oligomers changed due to significant increment of HMW-A (p < 0.01) and reduction of MMW-A (p < 0.05). By multivariate analysis, final HMW-A levels were significantly related to baseline ISIOGTT and final body weight (adjusted R(2) = 0.41). Our data suggest that HMW adiponectin may reflect baseline insulin sensitivity appropriately in the context of extreme obesity. Especially, we documented that HMW-A is promptly responsive to short-term weight loss prior to changes in insulin resistance, by a magnitude that is proportioned to whole body insulin sensitivity. This may suggest an insulin sensitivity-dependent control operated by HMW-A on metabolic dynamics of patients with extreme obesity.

  1. The plasma cyclic-AMP response to noise in humans and rats—short-term exposure to various noise levels

    NASA Astrophysics Data System (ADS)

    Iwamoto, M.; Dodo, H.; Ishii, F.; Yoneda, J.; Yamazaki, S.; Goto, H.

    1988-12-01

    Rats were exposed to short-term noise which was found to activate the hypothalamohypophyseal-adrenal system and result in a decrease of adrenal ascorbic acid (AAA) and an increase of serum corticosterone (SCS). The threshold limit value lay between 60 and 70 dB(A). To characterize better the effect of noise on the human hypothalamo-hypophyseal-adrenal system, a large group of subjects was exposed to short-term noise at 85 dB(A) and higher, and tested for levels of adrenocortical steroid (cortisol) and anterior pituitary hormones such as ACTH, growth hormone (GH) and prolactin (PRL). Results in humans showed hyperfunction of the hypothalamo-pituitary system. However, as the responses in rats and humans differed, a further experiment was performed using C-AMP, a second messenger mediating many of the effects of a variety of hormones. Plasma C-AMP in humans and rats increased significantly after exposure to noise greater than 70 dB(A). We suggest that plasma C-AMP could be useful as a sensitive index for noise-related stress in the daily living environment of humans and rats.

  2. Phlorotannin and antioxidant responses upon short-term exposure to UV radiation and elevated temperature in three south Pacific kelps.

    PubMed

    Cruces, Edgardo; Huovinen, Pirjo; Gómez, Iván

    2012-01-01

    Rapid adjustments of the photosynthetic machinery and efficient antioxidant mechanisms to scavenge harmful ROS are physiologic adaptions exhibited by intertidal seaweeds to persist in temperate regions. This study examines short-term (3 h) responses of three large kelps from the cold-temperate coast of Chile, normally adapted to water temperatures <16°C, but exposed abruptly to simultaneous high temperatures and UV radiation during low tide in summer. The kelps were exposed in the laboratory to three temperatures (10, 20 and 28°C) with and without UV radiation, and photochemical reactions, concentration of phlorotannins and antioxidant activity were examined. The exposure to elevated temperature (slightly exacerbated by the presence of UV radiation) decreased photochemical processes (measured as fluorescence kinetics) in the three studied species and increased lipid peroxidation in two of them. The concentration of total soluble phlorotannins was variable and correlated with the antioxidant activity in the presence of UV radiation. Insoluble phlorotannins did not change during the exposure. In all, the downregulation of the photochemical machinery, which was expressed as dynamic photoinhibition, and the rapid induction of soluble phlorotannins triggered by UV radiation minimized the effects of oxidative stress and maintained the operation of photochemical processes during short-term thermal stress.

  3. Effects of metomindate hydrochloride and tricaine methanesulfonate on the short term cortisol response in channel catfish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of metomidate hydrochloride and tricaine methanesulfonate (MS-222) on cortisol stress response of channel catfish, Ictalurus punctatus, were examined during 10 minutes of sedation. Channel catfish were assigned to three treatments: 1. Metomidate hydrochloride (12.5 mg/L), 2. MS-222 (100...

  4. Short-term physical training alters cardiovascular autonomic response amplitude and latencies.

    PubMed

    Sharma, Rajesh K; Deepak, K K; Bijlani, R L; Rao, P S

    2004-04-01

    This study reports the results of 15 days of exercise training in 25 adult males on cardiovascular autonomic response amplitude and latencies. A standard battery of autonomic function tests including both activity (tone) and reactivity was used. Parasympathetic activity as evaluated from Heart rate variability (HRV) showed no statistically significant change in both time and frequency domain measures, similarly Sympathetic activity as measured by QT/QS2 ratio showed no statistically significant change, but there was a trend of a decrease in sympathetic activity and an increase in parasympathetic activity. There were no changes in the parameters measuring parasympathetic reactivity. Sympathetic reactivity as evaluated by diastolic blood pressure responses to hand grip test (HGT) and cold pressor test (CPT) showed significant decreases. Time domain assessment of autonomic responses was done by measuring tachycardia and bradycardia latencies during Valsalva maneuver (VM) and lying to standing test (LST). Physical training resulted in a decrease in tachycardia latency during LST and a decrease in bradycardia latency during VM. We conclude from the present study that 15 days of physical training is not enough to alter autonomic activity and PNS reactivity but can result in changes in SNS reactivity and latency parameters. We hypothesize that a decrease in bradycardia latency during VM signifies a faster recovery of heart rate during VM and a decrease in tachycardia latency during LST denotes a delayed activation of the system both of which are favorable cardiovascular responses.

  5. EFFECT OF SHORT TERM DIESEL EXHAUST EXPOSURE ON NASAL RESPONSES TO INFLUENZA IN ALLERGIC RHINITICS.

    EPA Science Inventory

    Introduction: Recently published data suggest that diesel exhaust (DE) has special impact on allergic inflammation, suppressing Th1 and augmenting Th2 responses to allergen via oxidant stress effects on airway cells. Exposures to particulate air pollutants including DE are also a...

  6. Short-term precipitation exclusion alters microbial responses to soil moisture in a wet tropical forest.

    PubMed

    Waring, Bonnie G; Hawkes, Christine V

    2015-05-01

    Many wet tropical forests, which contain a quarter of global terrestrial biomass carbon stocks, will experience changes in precipitation regime over the next century. Soil microbial responses to altered rainfall are likely to be an important feedback on ecosystem carbon cycling, but the ecological mechanisms underpinning these responses are poorly understood. We examined how reduced rainfall affected soil microbial abundance, activity, and community composition using a 6-month precipitation exclusion experiment at La Selva Biological Station, Costa Rica. Thereafter, we addressed the persistent effects of field moisture treatments by exposing soils to a controlled soil moisture gradient in the lab for 4 weeks. In the field, compositional and functional responses to reduced rainfall were dependent on initial conditions, consistent with a large degree of spatial heterogeneity in tropical forests. However, the precipitation manipulation significantly altered microbial functional responses to soil moisture. Communities with prior drought exposure exhibited higher respiration rates per unit microbial biomass under all conditions and respired significantly more CO2 than control soils at low soil moisture. These functional patterns suggest that changes in microbial physiology may drive positive feedbacks to rising atmospheric CO2 concentrations if wet tropical forests experience longer or more intense dry seasons in the future.

  7. Behavioural responses of freshwater planarians after short-term exposure to the insecticide chlorantraniliprole.

    PubMed

    Rodrigues, Andreia C M; Henriques, Jorge F; Domingues, Inês; Golovko, Oksana; Žlábek, Vladimír; Barata, Carlos; Soares, Amadeu M V M; Pestana, João L T

    2016-01-01

    Recent advances in video tracking technologies provide the tools for a sensitive and reproducible analysis of invertebrate activity under stressful conditions nurturing the field of behavioural ecotoxicology. This study aimed to evaluate behavioural responses of the freshwater planarian Dugesia subtentaculata exposed to a model compound, chlorantraniliprole (CAP). This compound is an anthranilic diamide insecticide and due to its neurotoxic action can, at low concentrations, impair behaviour of exposed organisms. Behavioural endpoints measured included feeding and locomotor activities. Feeding responses were based on planarian predatory behaviour using Chironomus riparius larvae as prey. Locomotion was measured by the traditional planarian locomotor velocity (pLMV) assay and additionally using an automated video tracking system using a Zebrabox(®) (Viewpoint, France) device. While feeding and pLMV were significantly impaired at 131.7μg/L CAP, the video tracking system showed that total distance covered by planarians was significantly reduced at concentrations as low as 26.2μg/L CAP. Our results show that more advanced automated video recording systems can be used in the development of sensitive bioassays allowing a reliable, time- and cost-effective quantification of behaviour in aquatic invertebrates. Due to their ecological relevance, behavioural responses should not be disregarded in risk assessment strategies and we advocate the suitability of planarians as suitable organisms for behavioural ecotoxicological studies.

  8. Proteome Dynamics and Physiological Responses to Short-Term Salt Stress in Brassica napus Leaves.

    PubMed

    Jia, Huan; Shao, Mingquan; He, Yongjun; Guan, Rongzhan; Chu, Pu; Jiang, Haidong

    2015-01-01

    Salt stress limits plant growth and crop productivity and is an increasing threat to agriculture worldwide. In this study, proteomic and physiological responses of Brassica napus leaves under salt stress were investigated. Seedlings under salt treatment showed growth inhibition and photosynthesis reduction. A comparative proteomic analysis of seedling leaves exposed to 200 mM NaCl for 24 h, 48 h and 72 h was conducted. Forty-four protein spots were differentially accumulated upon NaCl treatment and 42 of them were identified, including several novel salt-responsive proteins. To determine the functional roles of these proteins in salt adaptation, their dynamic changes in abundance were analyzed. The results suggested that the up-accumulated proteins, which were associated with protein metabolism, damage repair and defense response, might contribute to the alleviation of the deleterious effect of salt stress on chlorophyll biosynthesis, photosynthesis, energy synthesis and respiration in Brassica napus leaves. This study will lead to a better understanding of the molecular basis of salt stress adaptation in Brassica napus and provides a basis for genetic engineering of plants with improved salt tolerance in the future.

  9. Short-term in vitro responses of human peripheral blood monocytes to ferritic stainless steel fiber networks.

    PubMed

    Spear, Rose L; Brooks, Roger A; Markaki, Athina E

    2013-05-01

    Beneficial effects on bone-implant bonding may accrue from ferromagnetic fiber networks on implants which can deform in vivo inducing controlled levels of mechanical strain directly in growing bone. This approach requires ferromagnetic fibers that can be implanted in vivo without stimulating undue inflammatory cell responses or cytotoxicity. This study examines the short-term in vitro responses, including attachment, viability, and inflammatory stimulation, of human peripheral blood monocytes to 444 ferritic stainless steel fiber networks. Two types of 444 networks, differing in fiber cross section and thus surface area, were considered alongside austenitic stainless steel fiber networks, made of 316L, a widely established implant material. Similar high percent seeding efficiencies were measured by CyQuant® on all fiber networks after 48 h of cell culture. Extensive cell attachment was confirmed by fluorescence and scanning electron microscopy, which showed round monocytes attached at various depths into the fiber networks. Medium concentrations of lactate dehydrogenase (LDH) and tumor necrosis factor alpha (TNF-α) were determined as indicators of viability and inflammatory responses, respectively. Percent LDH concentrations were similar for both 444 fiber networks at all time points, whereas significantly lower than those of 316L control networks at 24 h. All networks elicited low-level secretions of TNF-α, which were significantly lower than that of the positive control wells containing zymosan. Collectively, the results indicate that 444 networks produce comparable responses to medical implant grade 316L networks and are able to support human peripheral blood monocytes in short-term in vitro cultures without inducing significant inflammatory or cytotoxic effects.

  10. Visual short-term memory load reduces retinotopic cortex response to contrast.

    PubMed

    Konstantinou, Nikos; Bahrami, Bahador; Rees, Geraint; Lavie, Nilli

    2012-11-01

    Load Theory of attention suggests that high perceptual load in a task leads to reduced sensory visual cortex response to task-unrelated stimuli resulting in "load-induced blindness" [e.g., Lavie, N. Attention, distraction and cognitive control under load. Current Directions in Psychological Science, 19, 143-148, 2010; Lavie, N. Distracted and confused?: Selective attention under load. Trends in Cognitive Sciences, 9, 75-82, 2005]. Consideration of the findings that visual STM (VSTM) involves sensory recruitment [e.g., Pasternak, T., & Greenlee, M. Working memory in primate sensory systems. Nature Reviews Neuroscience, 6, 97-107, 2005] within Load Theory led us to a new hypothesis regarding the effects of VSTM load on visual processing. If VSTM load draws on sensory visual capacity, then similar to perceptual load, high VSTM load should also reduce visual cortex response to incoming stimuli leading to a failure to detect them. We tested this hypothesis with fMRI and behavioral measures of visual detection sensitivity. Participants detected the presence of a contrast increment during the maintenance delay in a VSTM task requiring maintenance of color and position. Increased VSTM load (manipulated by increased set size) led to reduced retinotopic visual cortex (V1-V3) responses to contrast as well as reduced detection sensitivity, as we predicted. Additional visual detection experiments established a clear tradeoff between the amount of information maintained in VSTM and detection sensitivity, while ruling out alternative accounts for the effects of VSTM load in terms of differential spatial allocation strategies or task difficulty. These findings extend Load Theory to demonstrate a new form of competitive interactions between early visual cortex processing and visual representations held in memory under load and provide a novel line of support for the sensory recruitment hypothesis of VSTM.

  11. Short-term physiological responses of wild and hatchery-produced red drum during angling

    USGS Publications Warehouse

    Gallman, E.A.; Isely, J.J.; Tomasso, J.R.; Smith, T.I.J.

    1999-01-01

    Serum cortisol concentrations, plasma glucose concentrations, plasma lactate concentrations, and plasma osmolalities increased in red drum Sciaenops ocellatus (26.0-65.5 cm total length) during angling in estuarine waters (17-33 g/L salinity, 21-31??C). Angling time varied from as fast as possible (10 s) to the point when fish ceased resisting (up to 350 s). The increases in the physiological characteristics were similar in wild and hatchery-produced fish. This study indicates that hatchery-produced red drum may be used in catch-and-release studies to simulate the responses of wild fish.

  12. Changes in the Size of the Active Microbial Pool Explain Short-Term Soil Respiratory Responses to Temperature and Moisture

    PubMed Central

    Salazar-Villegas, Alejandro; Blagodatskaya, Evgenia; Dukes, Jeffrey S.

    2016-01-01

    Heterotrophic respiration contributes a substantial fraction of the carbon flux from soil to atmosphere, and responds strongly to environmental conditions. However, the mechanisms through which short-term changes in environmental conditions affect microbial respiration still remain unclear. Microorganisms cope with adverse environmental conditions by transitioning into and out of dormancy, a state in which they minimize rates of metabolism and respiration. These transitions are poorly characterized in soil and are generally omitted from decomposition models. Most current approaches to model microbial control over soil CO2 production relate responses to total microbial biomass (TMB) and do not differentiate between microorganisms in active and dormant physiological states. Indeed, few data for active microbial biomass (AMB) exist with which to compare model output. Here, we tested the hypothesis that differences in soil microbial respiration rates across various environmental conditions are more closely related to differences in AMB (e.g., due to activation of dormant microorganisms) than in TMB. We measured basal respiration (SBR) of soil incubated for a week at two temperatures (24 and 33°C) and two moisture levels (10 and 20% soil dry weight [SDW]), and then determined TMB, AMB, microbial specific growth rate, and the lag time before microbial growth (tlag) using the Substrate-Induced Growth Response (SIGR) method. As expected, SBR was more strongly correlated with AMB than with TMB. This relationship indicated that each g active biomass C contributed ~0.04 g CO2-C h−1 of SBR. TMB responded very little to short-term changes in temperature and soil moisture and did not explain differences in SBR among the treatments. Maximum specific growth rate did not respond to environmental conditions, suggesting that the dominant microbial populations remained similar. However, warmer temperatures and increased soil moisture both reduced tlag, indicating that favorable

  13. Early and delayed long-term transcriptional changes and short-term transient responses during cold acclimation in olive leaves

    PubMed Central

    Leyva-Pérez, María de la O; Valverde-Corredor, Antonio; Valderrama, Raquel; Jiménez-Ruiz, Jaime; Muñoz-Merida, Antonio; Trelles, Oswaldo; Barroso, Juan Bautista; Mercado-Blanco, Jesús; Luque, Francisco

    2015-01-01

    Low temperature severely affects plant growth and development. To overcome this constraint, several plant species from regions having a cool season have evolved an adaptive response, called cold acclimation. We have studied this response in olive tree (Olea europaea L.) cv. Picual. Biochemical stress markers and cold-stress symptoms were detected after the first 24 h as sagging leaves. After 5 days, the plants were found to have completely recovered. Control and cold-stressed plants were sequenced by Illumina HiSeq 1000 paired-end technique. We also assembled a new olive transcriptome comprising 157,799 unigenes and found 6,309 unigenes differentially expressed in response to cold. Three types of response that led to cold acclimation were found: short-term transient response, early long-term response, and late long-term response. These subsets of unigenes were related to different biological processes. Early responses involved many cold-stress-responsive genes coding for, among many other things, C-repeat binding factor transcription factors, fatty acid desaturases, wax synthesis, and oligosaccharide metabolism. After long-term exposure to cold, a large proportion of gene down-regulation was found, including photosynthesis and plant growth genes. Up-regulated genes after long-term cold exposure were related to organelle fusion, nucleus organization, and DNA integration, including retrotransposons. PMID:25324298

  14. Early and delayed long-term transcriptional changes and short-term transient responses during cold acclimation in olive leaves.

    PubMed

    Leyva-Pérez, María de la O; Valverde-Corredor, Antonio; Valderrama, Raquel; Jiménez-Ruiz, Jaime; Muñoz-Merida, Antonio; Trelles, Oswaldo; Barroso, Juan Bautista; Mercado-Blanco, Jesús; Luque, Francisco

    2015-02-01

    Low temperature severely affects plant growth and development. To overcome this constraint, several plant species from regions having a cool season have evolved an adaptive response, called cold acclimation. We have studied this response in olive tree (Olea europaea L.) cv. Picual. Biochemical stress markers and cold-stress symptoms were detected after the first 24 h as sagging leaves. After 5 days, the plants were found to have completely recovered. Control and cold-stressed plants were sequenced by Illumina HiSeq 1000 paired-end technique. We also assembled a new olive transcriptome comprising 157,799 unigenes and found 6,309 unigenes differentially expressed in response to cold. Three types of response that led to cold acclimation were found: short-term transient response, early long-term response, and late long-term response. These subsets of unigenes were related to different biological processes. Early responses involved many cold-stress-responsive genes coding for, among many other things, C-repeat binding factor transcription factors, fatty acid desaturases, wax synthesis, and oligosaccharide metabolism. After long-term exposure to cold, a large proportion of gene down-regulation was found, including photosynthesis and plant growth genes. Up-regulated genes after long-term cold exposure were related to organelle fusion, nucleus organization, and DNA integration, including retrotransposons.

  15. Factors controlling short-term soil microbial response after laboratory heating. Preliminary results

    NASA Astrophysics Data System (ADS)

    Jiménez-Compán, Elizabeth; Jiménez-Morillo, Nicasio; Jordán, Antonio; Bárcenas-Moreno, Gema

    2015-04-01

    Soil microbial response after fire is controlled by numerous variables which conclude with a mosaic of results depending on organic carbon alterations or pH fire-induced changes. This fact has complicated the studies focused on post-fire microbial response, compiling high variability of opposite result in the bibliography. Soil laboratory heating cannot emulate a real wildfire effect on soil but lead us the possibility to control several variables and it is a valid tool to clarify the relative weight of different factors controlling microbial response after soil heating. In this preliminary study different heated treatments were applied to unaltered forest soil samples, obtaining 4 different heating treatments to simulate a range of fire intensities: unaltered-control (UH), and soil heated at 300, 450 and 500 °C. In order to isolate possible nutrient availability or pH heating-induced changes, different culture media were prepared using soil:water extract from each heating treatments and adding different supplements to obtain the total of 11 different culture media: unheated soil without supplements (UH-N-), unheated soil with nutrient supplement (UH-N+), soil heated at 300 °C without supplements (300-N-), soil heated at 300 °C with nutrient supplement (300-N+), soil heated at 300 °C with nutrient supplement and pH-buffered (300-N+pH); soil heated at 450 °C without supplements (450-N-), soil heated at 450 °C with nutrient supplement (450-N+), soil heated at 450 °C with nutrient supplement and pH-buffered (450-N+); soil heated at 500 °C without supplements (500-N-), soil heated at 500 °C with nutrient supplement (500-N+), soil heated at 500 °C with nutrient supplement and pH-buffered (500-N+). Each media was inoculated with different dilutions of a microbial suspension from the original unaltered soil, and the abundance of viable and cultivable microorganisms were measured by plate count method. In addition, the analysis of heating-induced soil organic

  16. Short-Term Moderately Elevated Intraocular Pressure Is Associated With Elevated Scotopic Electroretinogram Responses

    PubMed Central

    Choh, Vivian; Gurdita, Akshay; Tan, Bingyao; Prasad, Ratna C.; Bizheva, Kostadinka; Joos, Karen M.

    2016-01-01

    Purpose Moderately elevated intraocular pressure (IOP) is a risk factor for open-angle glaucoma. Some patients suffer glaucoma despite clinically measured normal IOPs. Fluctuations in IOP may have a significant role since IOPs are higher during sleep and inversion activities. Controlled transient elevations of IOPs in rats over time lead to optic nerve structural changes that are similar to the early changes observed in constant chronic models of glaucoma. Because early intervention decreases glaucoma progression, this study was done to determine if early physiological changes to the retina could be detected with noninvasive electrophysiological and optical imaging tests during moderately elevated IOP. Methods Intraocular pressures were raised to moderately high levels (35 mm Hg) in one eye of Sprague-Dawley rats while the other (control) eye was untreated. One group of rats underwent scotopic threshold response (STR) and electroretinogram (ERG) testing, while another 3 groups underwent optical coherence tomography (OCT) imaging, Western blot, or histologic evaluation. Results The amplitudes of the STR and ERG responses in eyes with moderately elevated IOPs were enhanced compared to the values before IOP elevation, and compared to untreated contralateral eyes. Structural changes to the optic nerve also occurred during IOP elevation. Conclusions Although ischemic IOP elevations are well-known to globally reduce components of the scotopic ERG, acute elevation in rats to levels often observed in untreated glaucoma patients caused an increase in these parameters. Further exploration of these phenomena may be helpful in better understanding the mechanisms mediating early retinal changes during fluctuating or chronically elevated IOP. PMID:27100161

  17. Laboratory Studies of the Short-term Responses of Freshwater Fish to Electromagnetic Fields

    SciTech Connect

    Bevelhimer, Mark S; Cada, Glenn F; Fortner, Allison M; Schweizer, Peter E; Riemer, Kristina P

    2013-01-01

    Hydrokinetic energy technologies are being proposed as an environmentally preferred means of generating electricity from river and tidal currents. Among the potential issues that must be investigated in order to resolve environmental concerns are the effects on aquatic organisms of electromagnetic fields created by underwater generators and transmission cables. The behavioral responses of common freshwater fishes to static and variable electromagnetic fields (EMF) that may be emitted by hydrokinetic projects were evaluated in laboratory experiments. Various fish species were exposed to either static (DC) EMF fields created by a permanent bar magnet or variable (AC) EMF fields created by a switched electromagnet for 48 h, fish locations were recorded with a digital imaging system, and changes in activity level and distribution relative to the magnet position were quantified at 5-min intervals. Experiments with fathead minnows, redear sunfish, striped bass, lake sturgeon, and channel catfish produced mixed results. Except for fathead minnows there was no effect on activity level. Only redear sunfish and channel catfish exhibited a change in distribution relative to the position of the magnet with an apparent attraction to the EMF source. In separate experiments, rapid behavioral responses of paddlefish and lake sturgeon to onset of the AC field were recorded with high-speed video. Paddlefish did not react to a variable, 60-Hz magnetic field like that which would be emitted by an AC generator or cable, but lake sturgeon consistently responded to the variable, AC-generated magnetic field with a variety of altered swimming behaviors. These results will be useful for determining under what circumstances cables or generators need to be positioned to minimize interactions with sensitive species.

  18. The efficient physiological strategy of a tomato landrace in response to short-term salinity stress.

    PubMed

    Moles, Tommaso Michele; Pompeiano, Antonio; Huarancca Reyes, Thais; Scartazza, Andrea; Guglielminetti, Lorenzo

    2016-12-01

    Landraces represent an important part of the biodiversity well-adapted under limiting environmental conditions. We investigated the response of two Southern Italy tomato landraces, the well-known San Marzano (our commercial standard) and a local accession called "Ciettaicale", to different levels of sodium chloride in water irrigation (from 0 up to 600 mM) for a short-time exposure (one week). The combination of the chlorophyll a fluorescence and gas exchange analyses suggested that Ciettaicale maintained a higher efficiency of photosystem II (PSII) photochemistry and CO2 utilization at high salinity concentrations than San Marzano. Stomatal and non-stomatal limitations occurred in San Marzano according to the reduction of maximum efficiency of PSII photochemistry and the increase of intercellular CO2 concentration. Higher Na(+)/K(+) ratio and higher concentration of total soluble sugars contributed to non-stomatal limitations in San Marzano leaves. These effects were significantly less evident in Ciettaicale. We also observed changes in total antioxidant capacity and leaf pigment content that emphasized the occurrence of modifications in the photosynthetic apparatus according to salt gradient. The more efficient assimilates supply and an integrated root protection system provided by sugars and antioxidants can explain the significantly higher root/shoot ratio in Ciettaicale. Overall, our results suggest that a comprehensive assessment of salinity tolerance in a genotypes comparison could be also obtained evaluating plant response to high salinity levels at early vegetative stage. In addition, further studies will be carried out in order to evaluate the possibility of using Ciettaicale in tomato improvement programs.

  19. Amphibian responses to wildfire in the western united states: Emerging patterns from short-term studies

    USGS Publications Warehouse

    Hossack, B.R.; Pilliod, D.S.

    2011-01-01

    The increased frequency and severity of large wildfires in the western United States is an important ecological and management issue with direct relevance to amphibian conservation. Although the knowledge of fire effects on amphibians in the region is still limited relative to most other vertebrate species, we reviewed the current literature to determine if there are evident patterns that might be informative for conservation or management strategies. Of the seven studies that compared pre- and post-wildfire data on a variety of metrics, ranging from amphibian occupancy to body condition, two reported positive responses and five detected negative responses by at least one species. Another seven studies used a retrospective approach to compare effects of wildfire on populations: two studies reported positive effects, three reported negative effects from wildfire, and two reported no effects. All four studies that included plethodontid salamanders reported negative effects on populations or individuals; these effects were greater in forests where fire had been suppressed and in areas that burned with high severity. Species that breed in streams are also vulnerable to post-wildfire changes in habitat, especially in the Southwest. Wildfire is also important for maintaining suitable habitat for diverse amphibian communities, although those results may not be evident immediately after an area burns. We expect that wildfire will extirpate few healthy amphibian populations, but it is still unclear how populations will respond to wildfire in the context of land management (including pre- and post-fire timber harvest) and fragmentation. Wildfire may also increase the risk of decline or extirpation for small, isolated, or stressed (e.g., from drought or disease) populations. Improved understanding of how these effects vary according to changes in fire frequency and severity are critical to form more effective conservation strategies for amphibians in the western United States.

  20. Soil Microbial Community Responses to Short-term Multiple Experimental Climate Change Drivers

    NASA Astrophysics Data System (ADS)

    Li, Guanlin; Lee, Jongyeol; Lee, Sohye; Roh, Yujin; Son, Yowhan

    2016-04-01

    It is agreed that soil microbial communities are responsible for the cycling of carbon and nutrients in ecosystems; however, the response of these microbial communities to climate change has not been clearly understood. In this study, we measured the direct and interactive effects of climate change drivers on soil bacterial and fungal communities (abundance and composition) in an open-field multifactor climate change experiment. The experimental treatment system was established with two-year-old Pinus densiflora seedlings at Korea University in April 2013, and consisted of six different treatments with three replicates: two levels of air temperature warming (control and +3° C) were crossed with three levels of precipitation manipulation (control, -30% and +30%). After 2.5 years of treatments, in August, 2015, soil samples were collected from the topsoil (0-15cm) of all plots (n=18). High-throughput sequencing technology was used to assess the abundance and composition of soil bacterial and fungal community. Analysis of variance for a blocked split-plot design was used to detect the effects of climate change drivers and their interaction on the abundance and composition of soil bacterial and fungal community. Our results showed that 1) only the significant effect of warming on fungal community abundance was observed (P <0.05); 2) on average, warming decreased both bacterial and fungal community abundance by 20.90% and 32.30%, 6.69% and 45.89%, 14.71% and 19.56% in control, decreased, and increased precipitation plots, respectively; 3) however, warming increased the relative bacterium/fungus ratio on average by 14.03%, 37.03% and 14.31% in control, decreased, and increased precipitation plots, respectively; 4) the phylogenetic distribution of bacterial and fungal groups and their relative abundance varied among treatments; 5) treatments altered the relative abundance of Ascomycota and Basidiomycota, where Ascomycota decreased with a concomitant increase in the

  1. Biological response of zebrafish embryos after short-term exposure to thifluzamide

    NASA Astrophysics Data System (ADS)

    Yang, Yang; Liu, Wenxian; Mu, Xiyan; Qi, Suzhen; Fu, Bin; Wang, Chengju

    2016-12-01

    Thifluzamide is a new amide fungicide, and its extensive application may have toxic effects on zebrafish. To better understand the underlying mechanism, we investigated in detail the potential toxic effects of thifluzamide on zebrafish embryos. In the present study, embryos were exposed to 0, 0.19, 1.90, and 2.85 mg/L thifluzamide for 4 days. Obvious pathological changes were found upon a histological exam, and negative changes in mitochondrial structure were observed under Transmission Electron Microscopy (TEM), which qualitatively noted the toxic effects of thifluzamide on embryos. Moreover, we quantitatively evaluated the enzyme activities [succinate dehydrogenase (SDH), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), caspases], the contents of malonaldehyde (MDA) and interleukin-8 (IL-8) and the expression levels of the related genes. This study suggests that the negative changes in mitochondrial structure and SDH activity might be responsible for oxidative damage, cell apoptosis and inflammation, which would facilitate the action of these factors in cell death and might play a crucial role during toxic events. In addition to providing the first description of the mechanism of the toxic effects of thifluzamide on embryos, this study also represents a step towards using embryos to assess mitochondrial metabolism and disease.

  2. Biological response of zebrafish embryos after short-term exposure to thifluzamide

    PubMed Central

    Yang, Yang; Liu, Wenxian; Mu, Xiyan; Qi, Suzhen; Fu, Bin; Wang, Chengju

    2016-01-01

    Thifluzamide is a new amide fungicide, and its extensive application may have toxic effects on zebrafish. To better understand the underlying mechanism, we investigated in detail the potential toxic effects of thifluzamide on zebrafish embryos. In the present study, embryos were exposed to 0, 0.19, 1.90, and 2.85 mg/L thifluzamide for 4 days. Obvious pathological changes were found upon a histological exam, and negative changes in mitochondrial structure were observed under Transmission Electron Microscopy (TEM), which qualitatively noted the toxic effects of thifluzamide on embryos. Moreover, we quantitatively evaluated the enzyme activities [succinate dehydrogenase (SDH), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), caspases], the contents of malonaldehyde (MDA) and interleukin-8 (IL-8) and the expression levels of the related genes. This study suggests that the negative changes in mitochondrial structure and SDH activity might be responsible for oxidative damage, cell apoptosis and inflammation, which would facilitate the action of these factors in cell death and might play a crucial role during toxic events. In addition to providing the first description of the mechanism of the toxic effects of thifluzamide on embryos, this study also represents a step towards using embryos to assess mitochondrial metabolism and disease. PMID:27924917

  3. Characterizing changes in soil bacterial community structure in response to short-term warming.

    PubMed

    Xiong, Jinbo; Sun, Huaibo; Peng, Fei; Zhang, Huayong; Xue, Xian; Gibbons, Sean M; Gilbert, Jack A; Chu, Haiyan

    2014-08-01

    High altitude alpine meadows are experiencing considerably greater than average increases in soil surface temperature, potentially as a result of ongoing climate change. The effects of warming on plant productivity and soil edaphic variables have been established previously, but the influence of warming on soil microbial community structure has not been well characterized. Here, the impact of 15 months of soil warming (both +1 and +2 °C) on bacterial community structure was examined in a field experiment on a Tibetan plateau alpine meadow using bar-coded pyrosequencing. Warming significantly changed (P < 0.05) the structure of the soil bacterial community, but the alpha diversity was not dramatically affected. Changes in the abundance of the Actinobacteria and Alphaproteobacteria were found to contribute the most to differences between ambient (AT) and artificially warmed conditions. A variance partitioning analysis (VPA) showed that warming directly explained 7.15% variation in bacterial community structure, while warming-induced changes in soil edaphic and plant phenotypic properties indirectly accounted for 28.3% and 20.6% of the community variance, respectively. Interestingly, certain taxa showed an inconsistent response to the two warming treatments, for example Deltaproteobacteria showed a decreased relative abundance at +1 °C, but a return to AT control relative abundance at +2 °C. This suggests complex microbial dynamics that could result from conditional dependencies between bacterial taxa.

  4. Short-term cropland responses to temperature extreme events during late winter

    NASA Astrophysics Data System (ADS)

    De Simon, G.; Alberti, G.; Delle Vedove, G.; Peressotti, A.; Zaldei, A.; Miglietta, F.

    2013-08-01

    In recent years, several studies have focused on terrestrial ecosystem response to extreme events. Most of this research has been conducted in natural ecosystems, but few have considered agroecosystems. In this study, we investigated the impact of a manipulated warmer or cooler late winter/early spring on the carbon budget and final harvest of a soybean crop (Glycine max (L.) Merr.). Soil temperature was altered by manipulating soil albedo by covering the soil surface with a layer of inert silica gravel. We tested three treatments - cooling (Co), warming (W), mix (M) - and control (C). An automated system continuously measured soil heterotrophic respiration (Rh), soil temperature profiles, and soil water content across the entire year in each plot. Phenological phases were periodically assessed and final harvest was measured in each plot. Results showed that treatments had only a transient effect on daily Rh rates, which did not result in a total annual carbon budget significantly different from control, even though cooling showed a significant reduction in final harvest. We also observed anticipation in emergence in both W and M treatments and a delay in emergence for Co. Moreover, plant density and growth increased in W and M and decreased in Co. In conclusion, from the results of our experiment we can assert that an increase in the frequency of both heat and cold waves is unlikely to have large effects on the overall annual carbon balance of irrigated croplands.

  5. Short-term cropland responses to temperature extreme events during late winter

    NASA Astrophysics Data System (ADS)

    De Simon, G.; Alberti, G.; Delle Vedove, G.; Peressotti, A.; Zaldei, A.; Miglietta, F.

    2013-04-01

    In recent years, several studies have focused on terrestrial ecosystem response to extreme events. Most of this research has been conducted in natural ecosystems, but few have considered agro-ecosystems. In this study, we investigated the impact of a manipulated warmer or cooler late winter-early spring on the carbon budget and final harvest of a soybean crop (Glycine max (L.) Merr.). Soil temperature was altered by manipulating soil albedo by covering the soil surface with a layer of inert silica gravel. We tested three treatments: cooling (Co), warming (W), mix (M) and control (C). An automated system continuously measured soil heterotrophic respiration (Rh), soil temperature profiles, and soil water content across the entire year in each plot. Phenological phases were periodically assessed and final harvest was measured in each plot. Results showed that treatments had only a transient effect on daily Rh rates which did not result in a total annual carbon budget significantly different from control, even though cooling showed a significant reduction in final harvest. We also observed anticipation in seed germination in both W and M treatments and a delay in germination for Co. Moreover, plant density and growth increased in W and M and decreased in Co.

  6. Short term response of insulin, glucose, growth hormone and corticosterone to acute vibration in rats.

    NASA Technical Reports Server (NTRS)

    Dolkas, C. B.; Leon, H. A.; Chackerian, M.

    1971-01-01

    Study carried out to obtain some notion of the initial phasing and interactive effects among some hormones known to be responsive to vibration stress. Sprague-Dawley derived rats were exposed to the acute effects of confinement and confinement with lateral (plus or minus G sub y) vibration. The coincident monitoring of glucose, insulin, growth hormone, and corticosterone plasma levels, during and immediately subsequent to exposure to brief low level vibration, exhibits the effects of inhibition of insulin release by epinephrine. The ability of insulin (IRI) to return rapidly to basal levels, from appreciably depressed levels during vibration, in the face of elevated levels of glucose is also shown. Corticosterone responds with almost equal rapidity, but in opposite phase to the IRI. The immuno-assayable growth hormone (IGH) dropped from a basal level of 32 ng/ml to 7.3 ng/ml immediately subsequent to vibration and remained at essentially that level throughout the experiment (60 min). Whether these levels represent a real fall in the rat or whether they merely follow the immuno-logically deficient form is still in question.

  7. Aerobic exercise does not compromise muscle hypertrophy response to short-term resistance training.

    PubMed

    Lundberg, Tommy R; Fernandez-Gonzalo, Rodrigo; Gustafsson, Thomas; Tesch, Per A

    2013-01-01

    This study tested the hypothesis that chronic aerobic and resistance exercise (AE+RE) would elicit greater muscle hypertrophy than resistance exercise only (RE). Ten men (25 ± 4 yr) performed 5 wk unilateral knee extensor AE+RE. The opposing limb was subjected to RE. AE completed 6 hr prior to RE consisted of ~45 min one-legged cycle ergometry. RE comprised 4 × 7 maximal concentric-eccentric knee extensions. Various indexes of in vivo knee extensor function were measured before and after training. Magnetic resonance imaging (MRI) assessed m. quadricep femoris (QF) cross-sectional area (CSA), volume, and signal intensity (SI). Biopsies obtained from m. vastus lateralis determined fiber CSA, enzyme levels, and gene expression of myostatin, atrogin-1, MuRF-1, PGC-1α, and VEGF. Increases (P < 0.05) in isometric strength and peak power, respectively, were comparable in AE+RE (9 and 29%) and RE (11 and 24%). AE+RE showed greater increase (14%; P < 0.05) in QF volume than RE (8%). Muscle fiber CSA increased 17% after AE+RE (P < 0.05) and 9% after RE (P > 0.05). QF SI increased (12%; P < 0.05) after AE+RE, but not RE. Neither AE+RE nor RE showed altered mRNA levels. Citrate synthase activity increased (P < 0.05) after AE+RE. The results suggest that the increased aerobic capacity shown with AE+RE was accompanied by a more robust increase in muscle size compared with RE. Although this response was not carried over to greater improvement in muscle function, it remains that intense AE can be executed prior to RE without compromising performance outcome.

  8. Cellular response to orthodontically-induced short-term hypoxia in dental pulp cells.

    PubMed

    Römer, Piero; Wolf, Michael; Fanghänel, Jochen; Reicheneder, Claudia; Proff, Peter

    2014-01-01

    Orthodontic force application is well known to induce sterile inflammation, which is initially caused by the compression of blood vessels in tooth-supporting apparatus. The reaction of periodontal ligament cells to mechanical loading has been thoroughly investigated, whereas knowledge on tissue reactions of the dental pulp is rather limited. The aim of the present trial is to analyze the effect of orthodontic treatment on the induction and cellular regulation of intra-pulpal hypoxia. To investigate the effect of orthodontic force on dental pulp cells, which results in circulatory disturbances within the dental pulp, we used a rat model for the immunohistochemical analysis of the accumulation of hypoxia-inducible factor-1α in the initial phase of orthodontic tooth movement. To further examine the regulatory role of circulatory disturbances and hypoxic conditions, we analyze isolated dental pulp cells from human teeth with regard to their specific reaction under hypoxic conditions by means of flow cytometry, immunoblot, ELISA and real-time PCR on markers (Hif-1α, VEGF, Cox-2, IL-6, IL-8, ROS, p65). In vivo experiments showed the induction of hypoxia in dental pulp after orthodontic tooth movement. The induction of oxidative stress in human dental pulp cells showed up-regulation of the pro-inflammatory and angiogenic genes Cox-2, VEGF, IL-6 and IL-8. The present data suggest that orthodontic tooth movement affects dental pulp circulation by hypoxia, which leads to an inflammatory response inside treated teeth. Therefore, pulp tissue may be expected to undergo a remodeling process after tooth movement.

  9. Behavioral responses to short-term transport in male and female Greater Rheas (Rhea americana) reared in captivity.

    PubMed

    Della Costa, N S; Lèche, A; Guzmán, D A; Navarro, J L; Marin, R H; Martella, M B

    2013-04-01

    Animal transport is an indispensable practice in species that need to be moved for management or commercial purposes. However, transport may have negative effects on individuals' welfare. The aims of the present work were to determine if the behavioral responses of adult Greater Rheas (Rhea americana) bred in captivity are sensitive to short-term transport and if males and females differ in their posttransport behavioral activity and recovery. Eight males and 8 females were placed in individual pens and allowed 6 d to habituate (d 1 to 6) before transport procedure. On the transport day (d 7), half of the birds (4 males and 4 females) were randomly assigned to a transport group that was captured and handled to be placed into the crates, exposed to a 30-min transport stressor, and immediately returned to their pens. Four transports with 1 different male and female each time were performed. The other half remained undisturbed and were used as controls. Behavior of all individuals was video-recorded during habituation days, after transport on d 7, and on the 2 following days (d 8 and 9) to evaluate pre- and posttransport behavioral activity for 2 h per day. No significant behavioral changes were observed during the last 2 d of the habituation period (d 5 and 6), suggesting that Greater Rheas were adapted to the housing conditions before transport. After transportation, several behaviors were affected: transported males and females showed null resting, transported females also showed reduced preening and increased vigilance (P < 0.05), whereas transported males showed increased drinking (P < 0.05) compared with their respective control groups. The results suggest that behavioral responses of captive-bred Greater Rheas are sensitive to short-term transport (which includes handling) and that males and females differ in their posttransport behavioral activity, recovering their overall basal levels on the third day posttransportation.

  10. Neuromuscular Responses to Short-Term Resistance Training With Traditional and Daily Undulating Periodization in Adolescent Elite Judoka.

    PubMed

    Ullrich, Boris; Pelzer, Thiemo; Oliveira, Sergio; Pfeiffer, Mark

    2016-08-01

    Ullrich, B, Pelzer, T, Oliveira, S, and Pfeiffer, M. Neuromuscular responses to short-term resistance training with traditional and daily undulating periodization in adolescent elite judoka. J Strength Cond Res 30(8): 2083-2099, 2016-The influence of different periodization models on neuromuscular outcomes after short-term strength training periods has not been examined in adolescent athletes. Eleven elite judoka (age: 14.8 ± 0.6 years, height: 163.2 ± 7.5 cm, body mass: 57.3 ± 11.1 kg, 5 boys/6 girls, and strength training experience: 2.7 ± 1.1 years) performed two 4-week strength training mesocycles (each with 12 sessions) with either traditional (TP) or daily undulating (DUP) periodization. Both mesocycles were separated by a 7-week washout period and added to the regular judo training. Strength training was performed as lifting and lowering of weights using squats, knee flexion curl, clean & jerk, snatch, bench press, barbell bench pull, and lat pull-down. The mesocycles were equated for the number of repetitions and different intensity zones (50-90% of 1 repetition maximum [1RM]), addressing the optimization of strength, power, or velocity. Laboratory and 1RM testing was carried out 2 times during the baseline (T1 and T2), after the TP mesocycle (T3), after the washout period (T4), and after the DUP mesocycle (T5). Isometric knee extensor and knee flexor maximum voluntary contractive capacity (MVC), electromyographic-estimated neural drive of the quadriceps femoris, vastus lateralis (VL) muscle architecture, and 1RMs of all training exercises were measured. ANOVA revealed moderate (5.5-13.5%) but significant (p ≤ 0.05) temporal gains in knee extensor MVC, 1RMs, and VL architecture during both the mesocycles. Wilcoxon tests detected no significant differences for the percentage changes of any outcome between the mesocycles. For adolescent judoka, TP and DUP were equally adept in improving neuromuscular outcomes during short-term training periods.

  11. Short-term versus long-term responses to drought stress: coupling manipulation experiments with gradient studies

    NASA Astrophysics Data System (ADS)

    Martin, Nicolas; Misson, Laurent

    2010-05-01

    Water availability is the main factor shaping plants form and function in Mediterranean ecosystems. Understanding the mechanisms that drive plants productivity in drought conditions is crucial in a climate change context. So far, functional relationships between drought stress and leaf physiology has mostly been studied in short term experiments unable to address the potential acclimation in leaf function and the link between short term responses and long term acclimation. Here we hypothesize that the functional relationships between drought and leaf physiology can change under the temporal scale at witch drought is applied. Hence, we measured leaf physiological parameters (gs, gm, Amax, Vcmax Jmax) implicated in the limitation of carbon assimilation on Holm Oak leaves using a design combining 2 contrasting field experiments: (1) a rainfall exclusion experiment simulating a spring extreme drought in order to study short term processes, (2) a natural rainfall gradient (650 mm to 1150 mm) made of 3 plots in order to study long term acclimation. For each experiment we related leaf physiological parameters and their respective limitation to carbon assimilation with predawn leaf water potential as a surrogate of drought stress. Results showed that functional relationships relating gs, Vcmax and Jmax to leaf water potential changed in the total rainfall exclusion, probably because of a strong effect of spring drought on phenology. In addition, trees in the wet plot of the rainfall gradient showed a stronger stomatal conductance decline relative to leaf water potential than trees in the dry plot. We interpret these changes as a result of structural modification at canopy level in the rainfall gradient related to changes in leaf area index (LAI), hydraulic adjustment or fine root/LAI ratio. As a consequence, stomatal limitation of carbon assimilation was stronger in the wet plot than in the dry plot, while total limitation was lower in the dry plot. Water conservation in

  12. Fast response and high sensitivity to microsaccades in a cascading-adaptation neural network with short-term synaptic depression.

    PubMed

    Yuan, Wu-Jie; Zhou, Jian-Fang; Zhou, Changsong

    2016-04-01

    Microsaccades are very small eye movements during fixation. Experimentally, they have been found to play an important role in visual information processing. However, neural responses induced by microsaccades are not yet well understood and are rarely studied theoretically. Here we propose a network model with a cascading adaptation including both retinal adaptation and short-term depression (STD) at thalamocortical synapses. In the neural network model, we compare the microsaccade-induced neural responses in the presence of STD and those without STD. It is found that the cascading with STD can give rise to faster and sharper responses to microsaccades. Moreover, STD can enhance response effectiveness and sensitivity to microsaccadic spatiotemporal changes, suggesting improved detection of small eye movements (or moving visual objects). We also explore the mechanism of the response properties in the model. Our studies strongly indicate that STD plays an important role in neural responses to microsaccades. Our model considers simultaneously retinal adaptation and STD at thalamocortical synapses in the study of microsaccade-induced neural activity, and may be useful for further investigation of the functional roles of microsaccades in visual information processing.

  13. Model predictions of features in microsaccade-related neural responses in a feedforward network with short-term synaptic depression

    NASA Astrophysics Data System (ADS)

    Zhou, Jian-Fang; Yuan, Wu-Jie; Zhou, Zhao; Zhou, Changsong

    2016-02-01

    Recently, the significant microsaccade-induced neural responses have been extensively observed in experiments. To explore the underlying mechanisms of the observed neural responses, a feedforward network model with short-term synaptic depression has been proposed [Yuan, W.-J., Dimigen, O., Sommer, W. and Zhou, C. Front. Comput. Neurosci. 7, 47 (2013)]. The depression model not only gave an explanation for microsaccades in counteracting visual fading, but also successfully reproduced several microsaccade-related features in experimental findings. These results strongly suggest that, the depression model is very useful to investigate microsaccade-related neural responses. In this paper, by using the model, we extensively study and predict the dependance of microsaccade-related neural responses on several key parameters, which could be tuned in experiments. Particularly, we provide a significant prediction that microsaccade-related neural response also complies with the property “sharper is better” observed in many contexts in neuroscience. Importantly, the property exhibits a power-law relationship between the width of input signal and the responsive effectiveness, which is robust against many parameters in the model. By using mean field theory, we analytically investigate the robust power-law property. Our predictions would give theoretical guidance for further experimental investigations of the functional role of microsaccades in visual information processing.

  14. Individual cells of Saccharomyces cerevisiae and Zygosaccharomyces bailii exhibit different short-term intracellular pH responses to acetic acid.

    PubMed

    Arneborg, N; Jespersen, L; Jakobsen, M

    2000-01-01

    The effects of perfusion with 2.7 and 26 mM undissociated acetic acid in the absence or presence of glucose on short-term intracellular pH (pH(i)) changes in individual Saccharormyces cerevisiae and Zygosaccharomyces bailii cells were studied using fluorescence-ratio-imaging microscopy and a perfusion system. In the S. cerevisiae cells, perfusion with acetic acid induced strong short-term pH(i) responses, which were dependent on the undissociated acetic acid concentration and the presence of glucose in the perfusion solutions. In the Z. bailii cells, perfusion with acetic acid induced only very weak short-term pH(i) responses, which were neither dependent on the undissociated acetic acid concentration nor on the presence of glucose in the perfusion solutions. These results clearly show that Z. bailii is more resistant than S. cerevisiae to short-term pH(i) changes caused by acetic acid.

  15. Short-term response of Holcus lanatus L. (Common Velvetgrass) to chemical and manual control at Yosemite National Park, USA

    USGS Publications Warehouse

    Jones, Laura J.; Ostoja, Steven M.; Brooks, Matthew L.; Hutten, Martin

    2015-01-01

    One of the highest priority invasive species at both Yosemite and Sequoia and Kings Canyon national parks is Holcus lanatus L. (common velvetgrass), a perennial bunchgrass that invades mid-elevation montane meadows. Despite velvetgrass being a high priority species, there is little information available on control techniques. The goal of this project was to evaluate the short-term response of a single application of common chemical and manual velvetgrass control techniques. The study was conducted at three montane sites in Yosemite National Park. Glyphosate spot-spray treatments were applied at 0.5, 1.0, 1.5, and 2.0% concentrations, and compared with hand pulling to evaluate effects on cover of common velvetgrass, cover of other plant species, and community species richness. Posttreatment year 1 cover of common velvetgrass was 12.1% ± 1.6 in control plots, 6.3% ± 1.5 averaged over the four chemical treatments (all chemical treatments performed similarly), and 13.6% ± 1.7 for handpulled plots. This represents an approximately 50% reduction in common velvetgrass cover in chemically- treated plots recoded posttreatment year 1 and no statistically significant reduction in hand pulled plots compared with controls. However, there was no treatment effect in posttreatment year 2, and all herbicide application rates performed similarly. In addition, there were no significant treatment effects on nontarget species or species richness. These results suggest that for this level of infestation and habitat type, (1) one year of hand pulling is not an effective control method and (2) glyphosate provides some level of control in the short-term without impact to nontarget plant species, but the effect is temporary as a single year of glyphosate treatment is ineffective over a two-year period.

  16. Dimethylsulfoniopropionate, superoxide dismutase and glutathione as stress response indicators in three corals under short-term hyposalinity stress

    PubMed Central

    Gardner, Stephanie G.; Nielsen, Daniel A.; Laczka, Olivier; Shimmon, Ronald; Beltran, Victor H.; Ralph, Peter J.; Petrou, Katherina

    2016-01-01

    Corals are among the most active producers of dimethylsulfoniopropionate (DMSP), a key molecule in marine sulfur cycling, yet the specific physiological role of DMSP in corals remains elusive. Here, we examine the oxidative stress response of three coral species (Acropora millepora, Stylophora pistillata and Pocillopora damicornis) and explore the antioxidant role of DMSP and its breakdown products under short-term hyposalinity stress. Symbiont photosynthetic activity declined with hyposalinity exposure in all three reef-building corals. This corresponded with the upregulation of superoxide dismutase and glutathione in the animal host of all three species. For the symbiont component, there were differences in antioxidant regulation, demonstrating differential responses to oxidative stress between the Symbiodinium subclades. Of the three coral species investigated, only A. millepora provided any evidence of the role of DMSP in the oxidative stress response. Our study reveals variability in antioxidant regulation in corals and highlights the influence life-history traits, and the subcladal differences can have on coral physiology. Our data expand on the emerging understanding of the role of DMSP in coral stress regulation and emphasizes the importance of exploring both the host and symbiont responses for defining the threshold of the coral holobiont to hyposalinity stress. PMID:26865302

  17. Transcriptomic analysis reveals importance of ROS and phytohormones in response to short-term salinity stress in Populus tomentosa

    PubMed Central

    Zheng, Lingyu; Meng, Yu; Ma, Jing; Zhao, Xiulian; Cheng, Tielong; Ji, Jing; Chang, Ermei; Meng, Chen; Deng, Nan; Chen, Lanzhen; Shi, Shengqing; Jiang, Zeping

    2015-01-01

    Populus tomentosa (Chinese white poplar) is well adapted to various extreme environments, and is considered an important species to study the effects of salinity stress on poplar trees. To decipher the mechanism of poplar's rapid response to short-term salinity stress, we firstly detected the changes in H2O2 and hormone, and then profiled the gene expression pattern of 10-week-old seedling roots treated with 200 mM NaCl for 0, 6, 12, and 24 h (h) by RNA-seq on the Illumina-Solexa platform. Physiological determination showed that the significant increase in H2O2 began at 6 h, while that in hormone ABA was at 24 h, under salt stress. Compared with controls (0 h), 3991, 4603, and 4903 genes were up regulated, and 1408, 2206, and 3461 genes were down regulated (adjusted P ≤ 0.05 and |log2Ratio|≥1) at 6, 12, and 24 h time points, respectively. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway annotation revealed that the differentially expressed genes (DEGs) were highly enriched in hormone- and reactive oxygen species-related biological processes, including “response to oxidative stress or abiotic stimulus,” “peroxidase activity,” “regulation of transcription,” “hormone synthetic and metabolic process,” “hormone signal transduction,” “antioxidant activity,” and “transcription factor activity.” Moreover, K-means clustering demonstrated that DEGs (total RPKM value>12 from four time points) could be categorized into four kinds of expression trends: quick up/down over 6 or 12 h, and slow up/down over 24 h. Of these, DEGs involved in H2O2- and hormone- producing and signal-related genes were further enriched in this analysis, which indicated that the two kinds of small molecules, hormones and H2O2, play pivotal roles in the short-term salt stress response in poplar. This study provides a basis for future studies of the molecular adaptation of poplar and other tree species to salinity stress. PMID:26442002

  18. Hsp70 expression and metabolite composition in response to short-term thermal changes in Folsomia candida (Collembola).

    PubMed

    Waagner, Dorthe; Heckmann, Lars-Henrik; Malmendal, Anders; Nielsen, Niels Chr; Holmstrup, Martin; Bayley, Mark

    2010-10-01

    In the present study the joint transcriptomic and metabolomic responses in Folsomia candida (Collembola) to temperature changes on a short-term scale were studied. Change in heat tolerance was examined as survival after a 35 degrees C heat shock (2h) in the course of either a fluctuating temperature regime (8 to 32 degrees C; pre-treated) or a constant temperature (20 degrees C; control) over a period of 24h. Exposure to a temperature increase from 20 to 32 degrees C (2.4 degrees C min(-)(1)) induced a significantly increased heat tolerance which continued throughout the experiment. Expression of the gene encoding heat shock protein Hsp70 was assessed at the mRNA level using real time quantitative polymerase chain reaction (QPCR). Hsp70 was rapidly induced and significantly increased by the temperature increase. The relative concentrations of low molecular weight metabolites were analysed in F. candida using nuclear magnetic resonance spectroscopy ((1)H NMR). A significant metabolomic divergence between pre-treated and control collembolans was evident; partly due to a significantly reduced relative concentration of five free amino acids (arginine, leucine, lysine, phenylalanine and tyrosine) in pre-treated collembolans. These results, obtained from ecological transcriptomics and metabolomics jointly generated insight on various levels into the combined responses to a changing environment.

  19. The Effect of Short-Term Dietary Fructose Supplementation on Gastric Emptying Rate and Gastrointestinal Hormone Responses in Healthy Men

    PubMed Central

    Yau, Adora M. W.; McLaughlin, John; Maughan, Ronald J.; Gilmore, William; Evans, Gethin H.

    2017-01-01

    This study aimed to examine gastric emptying rate and gastrointestinal hormone responses to fructose and glucose ingestion following 3 days of dietary fructose supplementation. Using the 13C-breath test method, gastric emptying rates of equicaloric fructose and glucose solutions were measured in 10 healthy men with prior fructose supplementation (fructose supplement, FS; glucose supplement, GS) and without prior fructose supplementation (fructose control, FC; glucose control, GC). In addition, circulating concentrations of acylated ghrelin (GHR), glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP), and insulin were determined, as well as leptin, lactate, and triglycerides. Increased dietary fructose ingestion resulted in accelerated gastric emptying rate of a fructose solution but not a glucose solution. No differences in GIP, GLP-1, or insulin incremental area under curve (iAUC) were found between control and supplement trials for either fructose or glucose ingestion. However, a trend for lower ghrelin iAUC was observed for FS compared to FC. In addition, a trend of lower GHR concentration was observed at 45 min for FS compared to FC and GHR concentration for GS was greater than GC at 10 min. The accelerated gastric emptying rate of fructose following short-term supplementation with fructose may be partially explained by subtle changes in delayed postprandial ghrelin suppression. PMID:28287413

  20. Progesterone Exacerbates Short-Term Effects of Traumatic Brain Injury on Supragranular Responses in Sensory Cortex and Over-Excites Infragranular Responses in the Long Term.

    PubMed

    Allitt, Benjamin J; Johnstone, Victoria P A; Richards, Katrina; Yan, Edwin B; Rajan, Ramesh

    2016-02-15

    Progesterone (P4) has been suggested as a neuroprotective agent for traumatic brain injury (TBI) because it ameliorates many post-TBI sequelae. We examined the effects of P4 treatment on the short-term (4 days post-TBI) and long-term (8 weeks post-TBI) aftermath on neuronal processing in the rodent sensory cortex of impact acceleration-induced diffuse TBI. We have previously reported that in sensory cortex, diffuse TBI induces a short-term hypoexcitation that is greatest in the supragranular layers and decreases with depth, but a long-term hyperexcitation that is exclusive to the supragranular layers. Now, adult male TBI-treated rats administered P4 showed, in the short term, even greater suppression in neural responses in supragranular layers but a reversal of the TBI-induced suppression in granular and infragranular layers. In long-term TBI there were only inconsistent effects of P4 on the TBI-induced hyperexcitation in supragranular responses but infragranular responses, which were not affected by TBI alone, were elevated by P4 treatment. Intriguingly, the effects in the injured brain were almost identical to P4 effects in the normal brain, as seen in sham control animals treated with P4: in the short term, P4 effects in the normal brain were identical to those exercised in the injured brain and in the long term, P4 effects in the normal brain were rather similar to what was seen in the TBI brain. Overall, these results provide no support for any protective effects of P4 treatment on neuronal encoding in diffuse TBI, and this was reflected in sensorimotor and other behavior tasks also tested here. Additionally, the effects suggest that mechanisms used for P4 effects in the normal brain are also intact in the injured brain.

  1. Short-term alpha-tocopherol treatment during neonatal period modulates pro-inflammatory response to endotoxin (LPS) challenge in the same calves several months later

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vitamin E, a major natural antioxidant, has been previously shown to attenuate pro-inflammatory response to immune challenge in cattle. Our objective was to evaluate the effect of short-term treatment with alpha-tocopherol in newborn calves on selected elements of the pro-inflamatory response to LPS...

  2. Interactions of Grazing History, Cattle Removal and Time since Rain Drive Divergent Short-Term Responses by Desert Biota

    PubMed Central

    Frank, Anke S. K.; Dickman, Chris R.; Wardle, Glenda M.; Greenville, Aaron C.

    2013-01-01

    Arid grasslands are used worldwide for grazing by domestic livestock, generating debate about how this pastoral enterprise may influence native desert biota. One approach to resolving this question is to experimentally reduce livestock numbers and measure the effects. However, a key challenge in doing this is that historical grazing impacts are likely to be cumulative and may therefore confound comparisons of the short-term responses of desert biota to changes in stocking levels. Arid areas are also subject to infrequent flooding rainfalls that drive productivity and dramatically alter abundances of flora and fauna. We took advantage of an opportunity to study the recent effects of a property-scale cattle removal on two properties with similarly varied grazing histories in central Australia. Following the removal of cattle in 2006 and before and after a significant rainfall event at the beginning of 2007, we sampled vegetation and small vertebrates on eight occasions until October 2008. Our results revealed significant interactions of time of survey with both grazing history and grazing removal for vascular plants, small mammals and reptiles. The mammals exhibited a three-way interaction of time, grazing history and grazing removal, thus highlighting the importance of careful sampling designs and timing for future monitoring. The strongest response to the cessation of grazing after two years was depressed reproductive output of plants in areas where cattle continued to graze. Our results confirm that neither vegetation nor small vertebrates necessarily respond immediately to the removal of livestock, but that rainfall events and cumulative grazing history are key determinants of floral and faunal performance in grassland landscapes with low and variable rainfall. We suggest that improved assessments could be made of the health of arid grazing environments if long-term monitoring were implemented to track the complex interactions that influence how native biota

  3. Defense Responses to Short-term Hypoxia and Seawater Acidification in the Thick Shell Mussel Mytilus coruscus.

    PubMed

    Sui, Yanming; Liu, Yimeng; Zhao, Xin; Dupont, Sam; Hu, Menghong; Wu, Fangli; Huang, Xizhi; Li, Jiale; Lu, Weiqun; Wang, Youji

    2017-01-01

    The rising anthropogenic atmospheric CO2 results in the reduction of seawater pH, namely ocean acidification (OA). In East China Sea, the largest coastal hypoxic zone was observed in the world. This region is also strongly impacted by ocean acidification as receiving much nutrient from Changjiang and Qiantangjiang, and organisms can experience great short-term natural variability of DO and pH in this area. In order to evaluate the defense responses of marine mussels under this scenario, the thick shell mussel Mytilus coruscus were exposed to three pH/pCO2 levels (7.3/2800 μatm, 7.7/1020 μatm, 8.1/376 μatm) at two dissolved oxygen concentrations (DO, 2.0, 6.0 mg L(-1)) for 72 h. Results showed that byssus thread parameters, such as the number, diameter, attachment strength and plaque area were reduced by low DO, and shell-closing strength was significantly weaker under both hypoxia and low pH conditions. Expression patterns of genes related to mussel byssus protein (MBP) were affected by hypoxia. Generally, hypoxia reduced MBP1 and MBP7 expressions, but increased MBP13 expression. In conclusion, both hypoxia and low pH induced negative effects on mussel defense responses, with hypoxia being the main driver of change. In addition, significant interactive effects between pH and DO were observed on shell-closing strength. Therefore, the adverse effects induced by hypoxia on the defense of mussels may be aggravated by low pH in the natural environments.

  4. Defense Responses to Short-term Hypoxia and Seawater Acidification in the Thick Shell Mussel Mytilus coruscus

    PubMed Central

    Sui, Yanming; Liu, Yimeng; Zhao, Xin; Dupont, Sam; Hu, Menghong; Wu, Fangli; Huang, Xizhi; Li, Jiale; Lu, Weiqun; Wang, Youji

    2017-01-01

    The rising anthropogenic atmospheric CO2 results in the reduction of seawater pH, namely ocean acidification (OA). In East China Sea, the largest coastal hypoxic zone was observed in the world. This region is also strongly impacted by ocean acidification as receiving much nutrient from Changjiang and Qiantangjiang, and organisms can experience great short-term natural variability of DO and pH in this area. In order to evaluate the defense responses of marine mussels under this scenario, the thick shell mussel Mytilus coruscus were exposed to three pH/pCO2 levels (7.3/2800 μatm, 7.7/1020 μatm, 8.1/376 μatm) at two dissolved oxygen concentrations (DO, 2.0, 6.0 mg L−1) for 72 h. Results showed that byssus thread parameters, such as the number, diameter, attachment strength and plaque area were reduced by low DO, and shell-closing strength was significantly weaker under both hypoxia and low pH conditions. Expression patterns of genes related to mussel byssus protein (MBP) were affected by hypoxia. Generally, hypoxia reduced MBP1 and MBP7 expressions, but increased MBP13 expression. In conclusion, both hypoxia and low pH induced negative effects on mussel defense responses, with hypoxia being the main driver of change. In addition, significant interactive effects between pH and DO were observed on shell-closing strength. Therefore, the adverse effects induced by hypoxia on the defense of mussels may be aggravated by low pH in the natural environments. PMID:28337153

  5. Short-term carbon cycling responses of a mature eucalypt woodland to gradual stepwise enrichment of atmospheric CO2 concentration.

    PubMed

    Drake, John E; Macdonald, Catriona A; Tjoelker, Mark G; Crous, Kristine Y; Gimeno, Teresa E; Singh, Brajesh K; Reich, Peter B; Anderson, Ian C; Ellsworth, David S

    2016-01-01

    Projections of future climate are highly sensitive to uncertainties regarding carbon (C) uptake and storage by terrestrial ecosystems. The Eucalyptus Free-Air CO2 Enrichment (EucFACE) experiment was established to study the effects of elevated atmospheric CO2 concentrations (eCO2 ) on a native mature eucalypt woodland with low fertility soils in southeast Australia. In contrast to other FACE experiments, the concentration of CO2 at EucFACE was increased gradually in steps above ambient (+0, 30, 60, 90, 120, and 150 ppm CO2 above ambient of ~400 ppm), with each step lasting approximately 5 weeks. This provided a unique opportunity to study the short-term (weeks to months) response of C cycle flux components to eCO2 across a range of CO2 concentrations in an intact ecosystem. Soil CO2 efflux (i.e., soil respiration or Rsoil ) increased in response to initial enrichment (e.g., +30 and +60 ppm CO2 ) but did not continue to increase as the CO2 enrichment was stepped up to higher concentrations. Light-saturated photosynthesis of canopy leaves (Asat ) also showed similar stimulation by elevated CO2 at +60 ppm as at +150 ppm CO2 . The lack of significant effects of eCO2 on soil moisture, microbial biomass, or activity suggests that the increase in Rsoil likely reflected increased root and rhizosphere respiration rather than increased microbial decomposition of soil organic matter. This rapid increase in Rsoil suggests that under eCO2, additional photosynthate was produced, transported belowground, and respired. The consequences of this increased belowground activity and whether it is sustained through time in mature ecosystems under eCO2 are a priority for future research.

  6. Microbial dynamics in upflow anaerobic sludge blanket (UASB) bioreactor granules in response to short-term changes in substrate feed

    SciTech Connect

    Kovacik, William P.; Scholten, Johannes C.; Culley, David E.; Hickey, Robert; Zhang, Weiwen; Brockman, Fred J.

    2010-08-01

    The complexity and diversity of the microbial communities in biogranules from an upflow anaerobic sludge blanket (UASB) bioreactor were determined in response to short-term changes in substrate feeds. The reactor was fed simulated brewery wastewater (SBWW) (70% ethanol, 15% acetate, 15% propionate) for 1.5 months (phase 1), acetate / sulfate for 2 months (phase 2), acetate-alone for 3 months (phase 3), and then a return to SBWW for 2 months (phase 4). Performance of the reactor remained relatively stable throughout the experiment as shown by COD removal and gas production. 16S rDNA, methanogen-associated mcrA and sulfate reducer-associated dsrAB genes were PCR amplified, then cloned and sequenced. Sequence analysis of 16S clone libraries showed a relatively simple community composed mainly of the methanogenic Archaea (Methanobacterium and Methanosaeta), members of the Green Non-Sulfur (Chloroflexi) group of Bacteria, followed by fewer numbers of Syntrophobacter, Spirochaeta, Acidobacteria and Cytophaga-related Bacterial sequences. Methanogen-related mcrA clone libraries were dominated throughout by Methanobacter and Methanospirillum related sequences. Although not numerous enough to be detected in our 16S rDNA libraries, sulfate reducers were detected in dsrAB clone libraries, with sequences related to Desulfovibrio and Desulfomonile. Community diversity levels (Shannon-Weiner index) generally decreased for all libraries in response to a change from SBWW to acetate-alone feed. But there was a large transitory increase noted in 16S diversity at the two-month sampling on acetate-alone, entirely related to an increase in Bacterial diversity. Upon return to SBWW conditions in phase 4, all diversity measures returned to near phase 1 levels.

  7. Interactions of grazing history, cattle removal and time since rain drive divergent short-term responses by desert biota.

    PubMed

    Frank, Anke S K; Dickman, Chris R; Wardle, Glenda M; Greenville, Aaron C

    2013-01-01

    Arid grasslands are used worldwide for grazing by domestic livestock, generating debate about how this pastoral enterprise may influence native desert biota. One approach to resolving this question is to experimentally reduce livestock numbers and measure the effects. However, a key challenge in doing this is that historical grazing impacts are likely to be cumulative and may therefore confound comparisons of the short-term responses of desert biota to changes in stocking levels. Arid areas are also subject to infrequent flooding rainfalls that drive productivity and dramatically alter abundances of flora and fauna. We took advantage of an opportunity to study the recent effects of a property-scale cattle removal on two properties with similarly varied grazing histories in central Australia. Following the removal of cattle in 2006 and before and after a significant rainfall event at the beginning of 2007, we sampled vegetation and small vertebrates on eight occasions until October 2008. Our results revealed significant interactions of time of survey with both grazing history and grazing removal for vascular plants, small mammals and reptiles. The mammals exhibited a three-way interaction of time, grazing history and grazing removal, thus highlighting the importance of careful sampling designs and timing for future monitoring. The strongest response to the cessation of grazing after two years was depressed reproductive output of plants in areas where cattle continued to graze. Our results confirm that neither vegetation nor small vertebrates necessarily respond immediately to the removal of livestock, but that rainfall events and cumulative grazing history are key determinants of floral and faunal performance in grassland landscapes with low and variable rainfall. We suggest that improved assessments could be made of the health of arid grazing environments if long-term monitoring were implemented to track the complex interactions that influence how native biota

  8. Responses of soil microeukaryotic communities to short-term fumigation-incubation revealed by MiSeq amplicon sequencing

    PubMed Central

    Chen, Lin; Xu, Jianming; Feng, Youzhi; Wang, Juntao; Yu, Yongjie; Brookes, Philip C.

    2015-01-01

    In soil microbiology, there is a “paradox” of soil organic carbon (SOC) mineralization, which is that even though chloroform fumigation destroys majority of the soil microbial biomass, SOC mineralization continues at the same rate as in the non-fumigated soil during the incubation period. Soil microeukaryotes as important SOC decomposers, however, their community-level responses to chloroform fumigation are not well understood. Using the 18S rRNA gene amplicon sequencing, we analyzed the composition, diversity, and C-metabolic functions of a grassland soil and an arable soil microeukaryotic community in response to fumigation followed by a 30-day incubation. The grassland and arable soil microeukaryotic communities were dominated by the fungal Ascomycota (80.5–93.1% of the fungal sequences), followed by the protistan Cercozoa and Apicomplexa. In the arable soil fungal community, the predominance of the class Sordariomycetes was replaced by the class Eurotiomycetes after fumigation at days 7 and 30 of the incubation. Fumigation changed the microeukaryotic α-diversity in the grassland soil at days 0 and 7, and β-diversity in the arable soil at days 7 and 30. Network analysis indicated that after fumigation fungi were important groups closely related to other taxa. Most phylotypes (especially Sordariomycetes, Dothideomycetes, Coccidia, and uncultured Chytridiomycota) were inhibited, and only a few were positively stimulated by fumigation. Despite the inhibited Sordariomycetes, the fumigated communities mainly consisted of Eurotiomycetes and Sordariomycetes (21.9 and 36.5% relative frequency, respectively), which are able to produce hydrolytic enzymes associated with SOC mineralization. Our study suggests that fumigation not only decreases biomass size, but modulates the composition and diversity of the soil microeukaryotic communities, which are capable of driving SOC mineralization by release of hydrolytic enzymes during short-term fumigation-incubation. PMID

  9. A synopsis of short-term response to alternative restoration treatments in sagebrush-steppe: the SageSTEP project

    USGS Publications Warehouse

    McIver, James; Brunson, Mark; Bunting, Steve; Chambers, Jeanne; Doescher, Paul; Grace, James; Hulet, April; Johnson, Dale; Knick, Steven T.; Miller, Richard; Pellant, Mike; Pierson, Fred; Pyke, David; Rau, Benjamin; Rollins, Kim; Roundy, Bruce; Schupp, Eugene; Tausch, Robin; Williams, Jason

    2014-01-01

    The Sagebrush Steppe Treatment Evaluation Project (SageSTEP) is an integrated long-term study that evaluates ecological effects of alternative treatments designed to reduce woody fuels and to stimulate the herbaceous understory of sagebrush steppe communities of the Intermountain West. This synopsis summarizes results through 3 yr posttreatment. Woody vegetation reduction by prescribed fire, mechanical treatments, or herbicides initiated a cascade of effects, beginning with increased availability of nitrogen and soil water, followed by increased growth of herbaceous vegetation. Response of butterflies and magnitudes of runoff and erosion closely followed herbaceous vegetation recovery. Effects on shrubs, biological soil crust, tree cover, surface woody fuel loads, and sagebrush-obligate bird communities will take longer to be fully expressed. In the short term, cool wet sites were more resilient than warm dry sites, and resistance was mostly dependent on pretreatment herbaceous cover. At least 10 yr of posttreatment time will likely be necessary to determine outcomes for most sites. Mechanical treatments did not serve as surrogates for prescribed fire in how each influenced the fuel bed, the soil, erosion, and sage-obligate bird communities. Woody vegetation reduction by any means resulted in increased availability of soil water, higher herbaceous cover, and greater butterfly numbers. We identified several trade-offs (desirable outcomes for some variables, undesirable for others), involving most components of the study system. Trade-offs are inevitable when managing complex natural systems, and they underline the importance of asking questions about the whole system when developing management objectives. Substantial spatial and temporal heterogeneity in sagebrush steppe ecosystems emphasizes the point that there will rarely be a “recipe” for choosing management actions on any specific area. Use of a consistent evaluation process linked to monitoring may be the

  10. Responses of soil CO2 fluxes to short-term experimental warming in alpine steppe ecosystem, Northern Tibet.

    PubMed

    Lu, Xuyang; Fan, Jihui; Yan, Yan; Wang, Xiaodan

    2013-01-01

    Soil carbon dioxide (CO2) emission is one of the largest fluxes in the global carbon cycle. Therefore small changes in the size of this flux can have a large effect on atmospheric CO2 concentrations and potentially constitute a powerful positive feedback to the climate system. Soil CO2 fluxes in the alpine steppe ecosystem of Northern Tibet and their responses to short-term experimental warming were investigated during the growing season in 2011. The results showed that the total soil CO2 emission fluxes during the entire growing season were 55.82 and 104.31 g C m(-2) for the control and warming plots, respectively. Thus, the soil CO2 emission fluxes increased 86.86% with the air temperature increasing 3.74°C. Moreover, the temperature sensitivity coefficient (Q 10) of the control and warming plots were 2.10 and 1.41, respectively. The soil temperature and soil moisture could partially explain the temporal variations of soil CO2 fluxes. The relationship between the temporal variation of soil CO2 fluxes and the soil temperature can be described by exponential equation. These results suggest that warming significantly promoted soil CO2 emission in the alpine steppe ecosystem of Northern Tibet and indicate that this alpine ecosystem is very vulnerable to climate change. In addition, soil temperature and soil moisture are the key factors that controls soil organic matter decomposition and soil CO2 emission, but temperature sensitivity significantly decreases due to the rise in temperature.

  11. Mutagenic and physiological responses in the juveniles of African catfish, Clarias gariepinus (Burchell 1822) following short term exposure to praziquantel.

    PubMed

    Nwani, Christopher Dididgwu; Nnaji, Macniel Chijioke; Oluah, Stanley Ndubuisi; Echi, Paul Chinedu; Nwamba, Helen Ogochukwu; Ikwuagwu, Ogbonnaya Egbe; Ajima, Malachy Nwigwe Okechukwu

    2014-08-01

    Praziquantel (PZQ) is an acylated quinoline-pyrazine originally developed for veterinary application but now one of the most used anti-helminthic drugs for treatment of certain trematodes and cestodes in both human and other animals. The present study investigated the mutagenic and physiological responses in the juveniles of African catfish, Clarias gariepinus following short term exposure to praziquantel. Based on the 53.52 mg/l 96 h LC50 of PZQ obtained, two sublethal concentrations of 5.35 and 10.70 mg/l of the drug were selected and fish were exposed to these concentrations and control for 15 days. Micronuclei induction in the peripheral blood of PZQ-exposed fish was highest on day 10 but the fish morphological parameters were not affected. The packed cell volume (PCV) was significantly reduced (p<0.05) from day 5 while red blood cells (RBC) and hemoglobin (Hb) significantly declined (p<0.05) on day 15. Macrocytic anemia was observed on day 1 of study and thereafter microcytic anemia developed on day 5 of study. The white blood cell (WBC) was significantly (p<0.05) elevated from day 10 of exposure while values of mean cellular volume (MCV), mean cellular hemoglobin (MCH) and mean cellular hemoglobin concentration (MCHC) were not significantly different (p>0.05) from the control. Alanine aminotransferase (ALT), aspartate aminotransferase (AST) and glucose levels significantly increased while protein reduced (p<0.05) throughout the exposure period but a mixed trend was observed in the leukocyte differentials. PZQ should be used with caution as sublethal exposure elicited micronucleus induction and alterations of hematological and biochemical parameters in the fish.

  12. Responses of Soil CO2 Fluxes to Short-Term Experimental Warming in Alpine Steppe Ecosystem, Northern Tibet

    PubMed Central

    Lu, Xuyang; Fan, Jihui; Yan, Yan; Wang, Xiaodan

    2013-01-01

    Soil carbon dioxide (CO2) emission is one of the largest fluxes in the global carbon cycle. Therefore small changes in the size of this flux can have a large effect on atmospheric CO2 concentrations and potentially constitute a powerful positive feedback to the climate system. Soil CO2 fluxes in the alpine steppe ecosystem of Northern Tibet and their responses to short-term experimental warming were investigated during the growing season in 2011. The results showed that the total soil CO2 emission fluxes during the entire growing season were 55.82 and 104.31 g C m-2 for the control and warming plots, respectively. Thus, the soil CO2 emission fluxes increased 86.86% with the air temperature increasing 3.74°C. Moreover, the temperature sensitivity coefficient (Q10) of the control and warming plots were 2.10 and 1.41, respectively. The soil temperature and soil moisture could partially explain the temporal variations of soil CO2 fluxes. The relationship between the temporal variation of soil CO2 fluxes and the soil temperature can be described by exponential equation. These results suggest that warming significantly promoted soil CO2 emission in the alpine steppe ecosystem of Northern Tibet and indicate that this alpine ecosystem is very vulnerable to climate change. In addition, soil temperature and soil moisture are the key factors that controls soil organic matter decomposition and soil CO2 emission, but temperature sensitivity significantly decreases due to the rise in temperature. PMID:23536854

  13. Short-Term Exposure of Paddy Soil Microbial Communities to Salt Stress Triggers Different Transcriptional Responses of Key Taxonomic Groups.

    PubMed

    Peng, Jingjing; Wegner, Carl-Eric; Liesack, Werner

    2017-01-01

    Soil salinization due to seawater intrusion along coastal areas is an increasing threat to rice cultivation worldwide. While the detrimental impact on rice growth and yield has been thoroughly studied, little is known about how severe salinity affects structure and function of paddy soil microbial communities. Here, we examined their short-term responses to half- and full-strength seawater salinity in controlled laboratory experiments. Slurry microcosms were incubated under anoxic conditions, with rice straw added as carbon source. Stress exposure time was for 2 days after a pre-incubation period of 7 days. Relative to the control, moderate (300 mM NaCl) and high (600 mM NaCl) salt stress suppressed both net consumption of acetate and methane production by 50% and 70%, respectively. Correspondingly, community-wide mRNA expression decreased by 50-65%, with significant changes in relative transcript abundance of family-level groups. mRNA turnover was clearly more responsive to salt stress than rRNA dynamics. Among bacteria, Clostridiaceae were most abundant and the only group whose transcriptional activity was strongly stimulated at 600 mM NaCl. In particular, clostridial mRNA involved in transcription/translation, fermentation, uptake and biosynthesis of compatible solutes, and flagellar motility was significantly enriched in response salt stress. None of the other bacterial groups were able to compete at 600 mM NaCl. Their responses to 300 mM NaCl were more diverse. Lachnospiraceae increased, Ruminococcaceae maintained, and Peptococcaceae, Veillonellaceae, and Syntrophomonadaceae decreased in relative mRNA abundance. Among methanogens, Methanosarcinaceae were most dominant. Relative to other family-level groups, salt stress induced a significant enrichment of transcripts related to the CO dehydrogenase/acetyl-coenzyme A synthase complex, methanogenesis, heat shock, ammonium uptake, and thermosomes, but the absolute abundance of methanosarcinal mRNA decreased. Most

  14. Short-Term Exposure of Paddy Soil Microbial Communities to Salt Stress Triggers Different Transcriptional Responses of Key Taxonomic Groups

    PubMed Central

    Peng, Jingjing; Wegner, Carl-Eric; Liesack, Werner

    2017-01-01

    Soil salinization due to seawater intrusion along coastal areas is an increasing threat to rice cultivation worldwide. While the detrimental impact on rice growth and yield has been thoroughly studied, little is known about how severe salinity affects structure and function of paddy soil microbial communities. Here, we examined their short-term responses to half- and full-strength seawater salinity in controlled laboratory experiments. Slurry microcosms were incubated under anoxic conditions, with rice straw added as carbon source. Stress exposure time was for 2 days after a pre-incubation period of 7 days. Relative to the control, moderate (300 mM NaCl) and high (600 mM NaCl) salt stress suppressed both net consumption of acetate and methane production by 50% and 70%, respectively. Correspondingly, community-wide mRNA expression decreased by 50–65%, with significant changes in relative transcript abundance of family-level groups. mRNA turnover was clearly more responsive to salt stress than rRNA dynamics. Among bacteria, Clostridiaceae were most abundant and the only group whose transcriptional activity was strongly stimulated at 600 mM NaCl. In particular, clostridial mRNA involved in transcription/translation, fermentation, uptake and biosynthesis of compatible solutes, and flagellar motility was significantly enriched in response salt stress. None of the other bacterial groups were able to compete at 600 mM NaCl. Their responses to 300 mM NaCl were more diverse. Lachnospiraceae increased, Ruminococcaceae maintained, and Peptococcaceae, Veillonellaceae, and Syntrophomonadaceae decreased in relative mRNA abundance. Among methanogens, Methanosarcinaceae were most dominant. Relative to other family-level groups, salt stress induced a significant enrichment of transcripts related to the CO dehydrogenase/acetyl-coenzyme A synthase complex, methanogenesis, heat shock, ammonium uptake, and thermosomes, but the absolute abundance of methanosarcinal mRNA decreased

  15. Short-term vegetation response following mechanical control of saltcedar (Tamarix spp.) on the Virgin River, Nevada, USA

    USGS Publications Warehouse

    Ostoja, Steven M.; Brooks, Matthew L.; Dudley, Tom; Lee, Steven R.

    2014-01-01

    and species diversity were very low, suggesting that targets of restoring vegetation to pre-invasion conditions were not met. Longer evaluation periods are needed to adequately evaluate how short-term post-treatment patterns translate to long-term patterns of plant community dynamics.

  16. Eelgrass indicator deployment system (EIDS): A low tech tool for short-term evaluation of eelgrass response to water quality

    EPA Science Inventory

    Eelgrass is often considered a sentinel species that can be used as an indicator of water clarity and quality. I used the Eelgrass Indicator Deployment System (EIDS) in a series of short term experiments to evaluate eelgrass growth and survival at a decline and a control site in...

  17. Responses of Emergent Behaviour in Headwater Catchments to Long-term and Short-term Environmental Change

    NASA Astrophysics Data System (ADS)

    Tetzlaff, D.; Soulsby, C.; Malcolm, I. A.; Brewer, M. J.

    2007-12-01

    Emergent behaviour of hydrological processes at the catchment scale often results in relatively simple and predictable functional characteristics which are underpinned by heterogeneous, complex processes at the small scale. It is unclear how such small-scale processes are affected by long- and short-term perturbations in forcing factors affected by various environmental changes. This leads to uncertainty in how emergent behaviour will change and how hydrology and hydrochemistry will respond at the catchment scale. A powerful resource in improving predictions of such responses is applying advanced statistical analysis to long-term data sets of conservative tracers, particularly in gauged catchments that are subject to marked environmental change. Changes in tracer behaviour can provide an integrated insight into the emergent response of system functioning and its non-linear characteristics. In this paper, we present the analysis of long-term tracer data collected since 1982 in 2 small (ca. 1km2) experimental catchments in the Scottish highlands. These have been affected by marked change and variability in driving variables of climate, land cover and rainfall chemistry: Annual rainfall ranged between 1490 and 2500mm and an average 1°C increase in air temperatures was observed over the monitoring period. In addition, forestry operations resulted in 70% of each catchment being clear felled. Finally, air pollution legislation targeting acid emissions has improved the quality of precipitation, resulting in a marked reduction in acid deposition. Long-term (20 year, weekly) time-series analyses of two tracers are used to assess changes in emergent catchment behaviour. Chloride input-output time series are analysed using a range of residence time models which highlighted non-stationarity in the catchment mean residence times (which ranged between 2-11 months for individual years) and corresponding residence time distributions. At the catchments scale these were driven

  18. Effect of short-term stainless steel welding fume inhalation exposure on lung inflammation, injury, and defense responses in rats

    SciTech Connect

    Antonini, James M. Stone, Sam; Roberts, Jenny R.; Chen, Bean; Schwegler-Berry, Diane; Afshari, Aliakbar A.; Frazer, David G.

    2007-09-15

    Many welders have experienced bronchitis, metal fume fever, lung function changes, and an increase in the incidence of lung infection. Questions remain regarding the possible mechanisms associated with the potential pulmonary effects of welding fume exposure. The objective was to assess the early effects of stainless steel (SS) welding fume inhalation on lung injury, inflammation, and defense responses. Male Sprague-Dawley rats were exposed to gas metal arc-SS welding fume at a concentration of 15 or 40 mg/m{sup 3} x 3 h/day for 1, 3, or 10 days. The control group was exposed to filtered air. To assess lung defense responses, some animals were intratracheally inoculated with 5 x 10{sup 4}Listeria monocytogenes 1 day after the last exposure. Welding particles were collected during exposure, and elemental composition and particle size were determined. At 1, 4, 6, 11, 14, and 30 days after the final exposure, parameters of lung injury (lactate dehydrogenase and albumin) and inflammation (PMN influx) were measured in the bronchoalveolar lavage fluid. In addition, particle-induced effects on pulmonary clearance of bacteria and macrophage function were assessed. SS particles were composed of Fe, Cr, Mn, and Ni. Particle size distribution analysis indicated the mass median aerodynamic diameter of the generated fume to be 0.255 {mu}m. Parameters of lung injury were significantly elevated at all time points post-exposure compared to controls except for 30 days. Interestingly, no significant difference in lung PMNs was observed between the SS and control groups at 1, 4, and 6 days post-exposure. After 6 days post-exposure, a dramatic increase in lung PMNs was observed in the SS group compared to air controls. Lung bacteria clearance and macrophage function were reduced and immune and inflammatory cytokines were altered in the SS group. In summary, short-term exposure of rats to SS welding fume caused significant lung damage and suppressed lung defense responses to bacterial

  19. Short-term sensory and cutaneous vascular responses to therapeutic ultrasound in the forearms of healthy volunteers

    PubMed Central

    2014-01-01

    Background Therapeutic ultrasound (US) is used for a variety of clinical pathologies and is thought to accelerate tissue repair and help with pain reduction via its thermal and nonthermal effects. The evidence on physiological effects of US on both sensory and vascular functions in humans is incomplete. Hence, the purpose of this study was to determine the short-term impact of two doses of US (3 MHz, 1:4, 0.25 W/cm2, 5 min; 1 MHz, continuous, 0.8 W/cm2, 3 min), on sensory and vascular responses in the healthy forearms. Methods Twenty healthy subjects were recruited (mean age, 29.6 ± 8.8 years) for the study. Superficial blood flow (SBF) in the distal forearms was determined using the tissue viability imaging system. Sensory perception thresholds (SPT) were determined from ring finger (C7, C8) to assess A-beta (at 2,000 Hz) and C fiber function (at 5 Hz), using a Neurometer CPT/C device. Subject’s two hands were randomly allocated to group order (AB/BA). Scores were obtained before and immediately after the application of US and control. Differences in these were analyzed using repeated measures. Results Both 3 MHz pulsed US and 1 MHz continuous US showed small to moderate (effect size = 0.12 to 0.68), statistically significant reductions in SBF (3 MHz, mean change = 2.8 AU and 1 MHz, mean change = 3.9 AU, p < 0.05 respectively), skin temperature (2.5°C and 1.1°C, p < 0.05), and SPT at 5 Hz (1.3 and 1 mA, p < 0.05) across time. SPT at 2,000 Hz remained unaltered by all three conditions (p > 0.05). Age and gender also had no effect on all outcome measures (p > 0.05). Conclusion This study demonstrated minor reductions in skin blood flow, skin temperatures, and C fiber perception thresholds immediately after 3 MHz, and 1 MHz US. The responses observed may have been due to a thermo-cooling effect of the gel or due to the direct effect of US on C fibers of median and ulnar nerves. US had a negligible effect on A-beta fibres. This would suggest that future

  20. Short-term response to waterlogging in Quercus petraea and Quercus robur: A study of the root hydraulic responses and the transcriptional pattern of aquaporins.

    PubMed

    Rasheed-Depardieu, Claire; Parelle, Julien; Tatin-Froux, Fabienne; Parent, Claire; Capelli, Nicolas

    2015-12-01

    We characterized the short-term response to waterlogging in Quercus petraea (Matt.) Liebl. and Quercus robur L. as the initial response towards their known long-term differences in tolerance to waterlogging. One-month old seedlings were subjected to hypoxic stress and leaf gas exchange, shoot water potential (Ψs) and root hydraulic conductivity (Lpr) were measured. In parallel, the expression of nine aquaporins (AQPs) along the primary root was analysed by quantitative RT-PCR. Results showed a similar reduction in net assimilation (A) and stomatal conductance (gs) for the two species. Notably, the response of Lpr differed temporally between the two species. Q. robur seedlings exhibited a significant early decline of Lpr within the first 5 h that returned to control levels after 48 h, whereas Q. petraea seedlings showed a delayed response with a significant decrease of Lpr exhibited only after 48 h. Transcriptional profiling revealed that three genes (PIP1;3, TIP2;1 and TIP2;2) were differentially regulated under stress conditions in the two oak species. Taken together, these results suggested species-specific responses to short-term waterlogging in terms of root water transport.

  1. Assessing colloid-bound metal export in response to short term changes in runoff from a forested catchment

    NASA Astrophysics Data System (ADS)

    Neubauer, E.; Kammer, F. v. d.; Knorr, K.-H.; Pfeiffer, S.; Reichert, M.; Hofmann, T.

    2012-04-01

    Soils can act as a source of metals and natural organic matter (NOM) in runoff from catchments. Amounts and intensity of rainfall may influence NOM export from catchments. The presence of NOM and other colloids in water may not only enhance metal export, but also significantly change metal speciation. In this study, we investigated the response of metal-colloid associations to short-term discharge variations in the runoff from a small forested catchment (Lehstenbach, Bavaria, Germany). Here, the discharge from the catchment outlet responds within hours to rain events. Near-surface flow in organic-rich layers and peat soils has been identified to increase dissolved organic carbon (DOC) concentrations during stormwater runoff. Flow Field-Flow Fractionation coupled to ICP-MS (FlowFFF-ICPMS) is a high-resolution size separation technique which was used for the detection and quantification of colloids and associated metals. Colloid-associated metals, dissolved metals and metals associated with low-molecular weight organic ligands were also separated by filtration (0.2 µm) and ultrafiltration (1000 g/mol MWCO). During baseflow DOC concentration was <6 mg/L and the pH ranged between 4.6 and 5.0. The DOC concentration exported at a given discharge was subject to strong seasonal variation and depended on the water level before the discharge event. DOC concentrations were up to 8 fold higher during stormwater runoff compared to baseflow. The export of aluminum, arsenic, rare earth elements (REE) and uranium from the catchment increased during stormwater runoff showing a strong correlation with NOM concentrations. This result was supported by FlowFFF-ICPMS data revealing that NOM was the only colloid type available for metal complexation during all hydrological conditions. A clear temporal pattern in the association with the NOM was observed for most of the metals under study: During baseflow, 70-100% (Fe), 90% (Al), 60-100% (REE) and 80-85% (U) were associated with the NOM

  2. Brain responses to symptom provocation and trauma-related short-term memory recall in coal mining accident survivors with acute severe PTSD.

    PubMed

    Hou, Cailan; Liu, Jun; Wang, Kun; Li, Lingjiang; Liang, Meng; He, Zhong; Liu, Yong; Zhang, Yan; Li, Weihui; Jiang, Tianzi

    2007-05-04

    Functional neuroimaging studies have largely been performed in patients with longstanding chronic posttraumatic stress disorder (PTSD). Additionally, memory function of PTSD patients has been proved to be impaired. We sought to characterize the brain responses of patients with acute PTSD and implemented a trauma-related short-term memory recall paradigm. Individuals with acute severe PTSD (n=10) resulting from a mining accident and 7 men exposed to the mining accident without PTSD underwent functional magnetic resonance imaging (fMRI) while performing the symptom provocation and trauma-related short-term memory recall paradigms. During symptom provocation paradigm, PTSD subjects showed diminished responses in right anterior cingulate gyrus, left inferior frontal gyrus and bilateral middle frontal gyrus and enhanced left parahippocampal gyrus response compared with controls. During the short-term memory recall paradigm, PTSD group showed diminished responses in right inferior frontal gyrus, right middle frontal and left middle occipital gyrus in comparison with controls. PTSD group exhibited diminished right parahippocampal gyrus response during the memory recall task as compared to the symptom provocation task. Our findings suggest that neurophysiological alterations and memory performance deficit have developed in acute severe PTSD.

  3. Endocrine, luteal and follicular responses after the use of the short-term protocol to synchronize ovulation in goats.

    PubMed

    Menchaca, A; Miller, V; Salveraglio, V; Rubianes, E

    2007-11-01

    The effect of the so-called Short-Term Protocol (5-day progesterone treatment+PGF(2)alpha) on ovarian activity and LH surge was studied in goats. The goats received 250IU eCG at the time of device withdrawal (eCG group; n=7), or 200microg of EB (estradiol benzoate) 24h after device withdrawal (EB group; n=8), or received neither eCG nor EB (control group; n=8). The Short-Term Protocol induced greater (4.1+/-1.1ng/ml) progesterone serum concentrations at 24h after start of the treatment, that declined to 0.2+/-0.1ng/ml at 12h after device withdrawal. In all of the groups, the maximum concentration of estradiol-17beta was reached at about 36h after device withdrawal. Maximum concentration was greater in the EB group (76.9+/-24.6pmol/l) than in the control group (41.8+/-9.0pmol/l; P<0.01), with the eCG group showing intermediate concentration (70.3+/-32.5pmol/l; P=NS). The LH peak occurred earlier in the eCG group (38.4+/-2.0h after device withdrawal) and in the EB group (41.0+/-4.1h), than in the control group (46.3+/-5.1h; P<0.05). Ovulation occurred earlier in the eCG group (5/7) and in the EB group (8/8) (58.8+/-2.7h and 63.0+/-5.6h, respectively), than in the control group (7/8) (70.2+/-8.3h; P<0.05). In summary, the Short-Term Protocol induced similar concentrations of progesterone among treated goats. In addition, eCG or EB resulted in a similar increase in estradiol-17beta and a similar LH surge, which induced ovulation in most females (86.7%) in a consistent interval (about 60h) after the end of progesterone exposure.

  4. Heart rate and blood pressure response to short-term head-down bed rest: a nonlinear approach.

    PubMed

    Balocchi, R; Di Garbo, A; Michelassi, C; Chillemi, S; Varanini, M; Barbi, M; Legramante, J M; Raimondi, G; Zbilut, J P

    2000-06-01

    Although it is well-known that prolonged exposure to microgravity environment such as in space travel results in derangements of orthostasis, recent evidence suggests that even short-term exposure may have similar effects and parallels such common examples as prolonged bed rest. Whereas spectral analysis of heart rate and systolic blood pressure have been unable to detect changes, we hypothesized that nonlinear indexes may be better able to uncover such perturbations. Eighteen healthy subjects were exposed to 4-hour head-down tilt, and of these, 4 exhibited fainting. Two nonlinear indexes, mutual information and recurrence quantification were used to analyze the data. Only recurrence quantification was able to detect a "decoupling" of heart rate and systolic blood pressure at rest using discriminant analysis (p < 0.05). These results suggest that orthostatic intolerance may be due to a decoupling of heart rate from systolic blood pressure reflexive activity occurring at rest.

  5. Transcriptomic and Physiological Responses of the Green Microalga Chlamydomonas reinhardtii during Short-Term Exposure to Subnanomolar Methylmercury Concentrations.

    PubMed

    Beauvais-Flück, Rebecca; Slaveykova, Vera I; Cosio, Claudia

    2016-07-05

    The effects of short-term exposure to subnanomolar methyl-mercury (MeHg) concentrations, representative of contaminated environments, on the microalga Chlamydomonas reinhardtii were assessed using both physiological end points and gene expression analysis. MeHg bioaccumulated and induced significant increase of the photosynthesis efficiency, while the algal growth, oxidative stress, and chlorophyll fluorescence were unaffected. At the molecular level, MeHg significantly dysregulated the expression of genes involved in motility, energy metabolism, lipid metabolism, metal transport, and antioxidant enzymes. Data suggest that the cells were able to cope with subnanomolar MeHg exposure, but this tolerance resulted in a significant cost to the cell energy and reserve metabolism as well as ample changes in the nutrition and motility of C. reinhardtii. The present results allowed gaining new insights on the effects and uptake mechanisms of MeHg at subnanomolar concentrations in aquatic primary producers.

  6. Deferred feeding and body weight responses to short-term interruption of fuel acquisition: impact of estradiol.

    PubMed

    Ibrahim, B A; Briski, K P

    2015-07-01

    Short-term abstinence from food intake, planned or unplanned, is unavoidable in modern life, but negatively correlated with appetite control and obesity. This study investigated the role of estradiol in feeding and body weight (BW) reactions to short-span cessation of feeding. During acute 1-6-h re-feeding, 12-h food-deprived (FD), estradiol benzoate (EB)-implanted ovariectomized rats ate less food and gained less weight than FD animals implanted with oil (O). Full fed (FF)- and FD-EB consumed equal amounts of food over 24 h, but weight gain was greater in the latter; 24-h food intake and BW gain in FD-O exceeded FD-EB. Caudal fourth ventricular administration of the AMPK activator AICAR increased dorsal vagal complex AMPK activity in FD-EB and FD-O, but elicited dissimilar adjustments in hypothalamic metabolic neuropeptide transmitter expression, while respectively enhancing or reducing acute re-feeding in these animals and reversing FD-O weight gain. Drug-treated FD-EB and FD-O exhibited respective feeding and weight gain increases between 6-24 h. AICAR enhanced 24-h consumption in FD-EB vs. FF-EB, but cumulative intake and BW gain were greater in AICAR-treated FD-O vs. FD-EB. Results show that estradiol limits acute re-feeding after short-term feeding suspension, but augments acute re-feeding when energy depletion coincides with suspended feeding. This compound metabolic stress exerts steroid-dependent effects during later resumption of circadian-induced feeding, for example, increased consumption vs. weight gain in the presence vs. absence of estradiol. These studies provide novel evidence that estrogen mitigates acute and post-acute adverse effects of disrupted fuel acquisition on energy balance.

  7. The effects of creatine supplementation on muscular performance and body composition responses to short-term resistance training overreaching.

    PubMed

    Volek, Jeff S; Ratamess, Nicholas A; Rubin, Martyn R; Gómez, Ana L; French, Duncan N; McGuigan, Michael M; Scheett, Timothy P; Sharman, Matthew J; Häkkinen, Keijo; Kraemer, William J

    2004-05-01

    To determine the effects of creatine supplementation during short-term resistance training overreaching on performance, body composition, and resting hormone concentrations, 17 men were randomly assigned to supplement with 0.3 g/kg per day of creatine monohydrate (CrM: n=9) or placebo (P: n=8) while performing resistance exercise (5 days/week for 4 weeks) followed by a 2-week taper phase. Maximal squat and bench press and explosive power in the bench press were reduced during the initial weeks of training in P but not CrM. Explosive power in the bench press, body mass, and lean body mass (LBM) in the legs were augmented to a greater extent in CrM ( Pshort-term resistance training overreaching with creatine supplementation and these changes are not related to changes in circulating hormone concentrations obtained in the resting, postabsorptive state. In addition, creatine supplementation appears to be effective for maintaining muscular performance during the initial phase of high-volume resistance training overreaching that otherwise results in small performance decrements.

  8. Short-term variations of phytoplankton communities in response to anthropogenic stressors in a highly altered temperate estuary

    NASA Astrophysics Data System (ADS)

    Sin, Yongsik; Jeong, Byungkwan

    2015-04-01

    Data for phytoplankton size classes, taxonomy, and water properties were collected through an episodic freshwater discharge event (4 days) in the temperate Youngsan River estuary, which is highly disturbed by manually regulated inputs of freshwater from a sea dike, to investigate the effects of an acute change in anthropogenic stressors on the short-term dynamics of phytoplankton and their surrounding environments. The salinity of the well-mixed saline water (33.2-33.5) decreased to as low as 4.0 and water temperature increased to 24.0 °C during the freshwater discharge, resulting in a stratified water column in the upper region of the estuary. During the discharge, chlorophyll a (chl a) concentrations increased to as much as 15.66 μg L-1 with micro-sized phytoplankton being dominant due to the presence of micro-sized freshwater phytoplankton, mostly Aulacoseira ambigua (98% in cell abundance), transported from the reservoir. Primary production decreased to as little as 87.9 mg C m-2 d-1, although nutrients such as NO2- + NO3- were supplied by the freshwater inputs of the discharge. Following the discharge, dinoflagellate blooms, dominated by Heterocapsa sp. (>88%), a nano-sized red tide species, developed in the upper regions of the estuary with peaks in chl a concentrations reaching as high as 30.33 μg L-1. Another red tide species, Prorocentrum micans, was also dominant in the estuary, suggesting that harmful algal blooms (HABs) are associated with anthropogenic stressors related to the freshwater inputs. The Shannon diversity index decreased to 0.18 while the Simpson dominance index increased to 0.94 during the discharge, but the diversity increased again following the discharge. The phytoplankton communities and diversity changed along the salinity gradient, corresponding to an "ecocline" pattern. The results of multivariate statistical analysis suggested that phytoplankton species and size structure were controlled mainly by salinity, water temperature

  9. Short-term response of sleep-potentiated spiking to high-dose diazepam in electric status epilepticus during sleep.

    PubMed

    Sánchez Fernández, Iván; Hadjiloizou, Stavros; Eksioglu, Yaman; Peters, Jurriaan M; Takeoka, Masanori; Tas, Emir; Abdelmoumen, Imane; Rotenberg, Alexander; Kothare, Sanjeev V; Riviello, James J; Loddenkemper, Tobias

    2012-05-01

    We describe the short-term effects of high-dose oral diazepam on sleep-potentiated epileptiform activity in patients with electric status epilepticus during sleep. We enrolled patients treated with high-dose oral bedtime diazepam from 2001-2009. We defined spike percentage as the percentage of 1-second bins containing at least one spike, and calculated it during three randomly selected 5-minute samples of wakefulness throughout the day and during the first 5 minutes of every hour of non-rapid eye movement sleep at night. In this study, patients were considered to demonstrate sleep-potentiated epileptiform activity when their spike percentage during sleep was increased by ≥50% compared with wakefulness. Twenty-nine children (18 boys) were included (median age, 7.4 years). Twenty-four hours after receiving high-dose diazepam, epileptiform activity was significantly reduced (76.7% at baseline vs 40.8% 24 hours after high-dose diazepam; Wilcoxon signed ranks test, Z = -4.287, P < 0.0001). Seven patients (24.1%) manifested mild, reversible side effects during the first 48 hours after diazepam administration. High-dose oral diazepam effectively and safely reduced epileptiform activity in patients with electric status epilepticus during sleep.

  10. Short-term changes of fructans in ryegrass (Lolium multiflorum 'Lema') in response to urban air pollutants and meteorological conditions.

    PubMed

    Sandrin, Carla Zuliani; Figueiredo-Ribeiro, Rita de Cássia Leone; Delitti, Welington Braz Carvalho; Domingos, Marisa

    2013-10-01

    We investigated whether the fructan content, a storage carbohydrate, of Lolium multiflorum 'Lema' plants grown in a subtropical urban environment characterized by typical diurnal profiles of air pollutants and meteorological conditions changed over the course of a day during different seasons. Plants were collected every 2h on the last day of each two-month seasonal field experiment and separated into shoot (stubble or stubble+leaf blades) and roots for carbohydrate analyses and biomass determination. Diurnal contents of total fructose in the stubbles increased with high temperatures. In the roots, fructose accumulation showed a positive relation with hourly variations of both temperature and particulate matter and a negative relation with irradiance and SO2. Seasonal variation in shoot and root biomasses coincided with the seasonal variation of total fructose and were negatively affected by relative humidity and SO2, respectively. We concluded that hourly changes of fructans over the course of a day may increase the ability of L. multiflorum to tolerate short-term oscillations in weather and air pollution commonly observed in the subtropical urban environment, increasing its efficiency in monitoring air quality.

  11. Does the stress response predict the ability of wild birds to adjust to short-term captivity? A study of the rock pigeon (Columbia livia)

    PubMed Central

    Parenteau, Charline; Trouvé, Colette; Angelier, Nicole

    2016-01-01

    Although the transfer of wild animals to captivity is crucial for conservation purposes, this process is often challenging because some species or individuals do not adjust well to captive conditions. Chronic stress has been identified as a major concern for animals held on long-term captivity. Surprisingly, the first hours or days of captivity have been relatively overlooked. However, they are certainly very stressful, because individuals are being transferred to a totally novel and confined environment. To ensure the success of conservation programmes, it appears crucial to better understand the proximate causes of interspecific and interindividual variability in the sensitivity to these first hours of captivity. In that respect, the study of stress hormones is relevant, because the hormonal stress response may help to assess whether specific individuals or species adjust, or not, to such captive conditions (‘the stress response-adjustment to captivity hypothesis’). We tested this hypothesis in rock pigeons by measuring their corticosterone stress response and their ability to adjust to short-term captivity (body mass loss and circulating corticosterone levels after a day of captivity). We showed that an increased corticosterone stress response is associated with a lower ability to adjust to short-term captivity (i.e. higher body mass loss and circulating corticosterone levels). Our study suggests, therefore, that a low physiological sensitivity to stress may be beneficial for adjusting to captivity. Future studies should now explore whether the stress response can be useful to predict the ability of individuals from different populations or species to not only adjust to short-term but also long-term captivity. PMID:28083117

  12. Does the stress response predict the ability of wild birds to adjust to short-term captivity? A study of the rock pigeon (Columbia livia).

    PubMed

    Angelier, Frédéric; Parenteau, Charline; Trouvé, Colette; Angelier, Nicole

    2016-12-01

    Although the transfer of wild animals to captivity is crucial for conservation purposes, this process is often challenging because some species or individuals do not adjust well to captive conditions. Chronic stress has been identified as a major concern for animals held on long-term captivity. Surprisingly, the first hours or days of captivity have been relatively overlooked. However, they are certainly very stressful, because individuals are being transferred to a totally novel and confined environment. To ensure the success of conservation programmes, it appears crucial to better understand the proximate causes of interspecific and interindividual variability in the sensitivity to these first hours of captivity. In that respect, the study of stress hormones is relevant, because the hormonal stress response may help to assess whether specific individuals or species adjust, or not, to such captive conditions ('the stress response-adjustment to captivity hypothesis'). We tested this hypothesis in rock pigeons by measuring their corticosterone stress response and their ability to adjust to short-term captivity (body mass loss and circulating corticosterone levels after a day of captivity). We showed that an increased corticosterone stress response is associated with a lower ability to adjust to short-term captivity (i.e. higher body mass loss and circulating corticosterone levels). Our study suggests, therefore, that a low physiological sensitivity to stress may be beneficial for adjusting to captivity. Future studies should now explore whether the stress response can be useful to predict the ability of individuals from different populations or species to not only adjust to short-term but also long-term captivity.

  13. Short-term high-intensity interval exercise training attenuates oxidative stress responses and improves antioxidant status in healthy humans.

    PubMed

    Bogdanis, G C; Stavrinou, P; Fatouros, I G; Philippou, A; Chatzinikolaou, A; Draganidis, D; Ermidis, G; Maridaki, M

    2013-11-01

    This study investigated the changes in oxidative stress biomarkers and antioxidant status indices caused by a 3-week high-intensity interval training (HIT) regimen. Eight physically active males performed three HIT sessions/week over 3 weeks. Each session included four to six 30-s bouts of high-intensity cycling separated by 4 min of recovery. Before training, acute exercise elevated protein carbonyls (PC), thiobarbituric acid reactive substances (TBARS), glutathione peroxidase (GPX) activity, total antioxidant capacity (TAC) and creatine kinase (CK), which peaked 24h post-exercise (252 ± 30%, 135 ± 17%, 10 ± 2%, 85 ± 14% and 36 ± 13%, above baseline, respectively; p<0.01), while catalase activity (CAT) peaked 30 min post-exercise (56 ± 18% above baseline; p<0.01). Training attenuated the exercise-induced increase in oxidative stress markers (PC by 13.3 ± 3.7%; TBARS by 7.2 ± 2.7%, p<0.01) and CK activity, despite the fact that total work done was 10.9 ± 3.6% greater in the post- compared with the pre-training exercise test. Training also induced a marked elevation of antioxidant status indices (TAC by 38.4 ± 7.2%; CAT by 26.2 ± 10.1%; GPX by 3.0 ± 0.6%, p<0.01). Short-term HIT attenuates oxidative stress and up-regulates antioxidant activity after only nine training sessions totaling 22 min of high intensity exercise, further supporting its positive effect not only on physical conditioning but also on health promotion.

  14. Short-term response of hip mobilizations and exercise in individuals with chronic low back pain: a case series

    PubMed Central

    Burns, Scott A; Mintken, Paul E; Austin, Gary P; Cleland, Joshua

    2011-01-01

    Study design A case series of consecutive patients with chronic low back pain. Background and purpose In patients with chronic low back pain (CLBP), the importance of impairments at the hip joints is unclear. However, it has been postulated that impairments at the hip joints may contribute to CLBP. The purpose of this case series was to investigate the short-term outcomes in patients with CLBP managed with impairment-based manual therapy and exercise directed at the hip joints. Methods Eight consecutive patients (mean age: 43·9 years) with a primary report of CLBP (>6 months) without radiculopathy were treated with a standardized approach of manual physical therapy and exercise directed at bilateral hip impairments for a total of three sessions over approximately 1 week. At initial examination, all patients completed a numeric rating pain scale (NPRS), Oswestry disability index (ODI), fear-avoidance beliefs questionnaire (FABQ), and patient-specific functional scale (PSFS). At the second and third treatment sessions, each patient completed all outcome measures as well as the Global Rating of Change (GROC). Results Five of the eight (62·5%) patients reported ‘moderately better’ or higher (>+4) on the GROC at the third session, indicating a moderate improvement in self-reported symptoms. These five individuals also experienced a 24·4% reduction in ODI scores. Discussion This case series suggests that an impairment-based approach directed at the hip joints may lead to improvements in pain, function, and disability in patients with CLBP. A neurophysiologic mechanism may be a plausible explanation regarding the clinical outcomes of this study. A larger, well-controlled trial is needed to determine the potential effectiveness of this approach with patients with CLBP. PMID:22547920

  15. Short-term metabolic and growth responses of the cold-water coral Lophelia pertusa to ocean acidification

    NASA Astrophysics Data System (ADS)

    Hennige, S. J.; Wicks, L. C.; Kamenos, N. A.; Bakker, D. C. E.; Findlay, H. S.; Dumousseaud, C.; Roberts, J. M.

    2014-01-01

    Cold-water corals are associated with high local biodiversity, but despite their importance as ecosystem engineers, little is known about how these organisms will respond to projected ocean acidification. Since preindustrial times, average ocean pH has decreased from 8.2 to ~8.1, and predicted CO2 emissions will decrease by up to another 0.3 pH units by the end of the century. This decrease in pH may have a wide range of impacts upon marine life, and in particular upon calcifiers such as cold-water corals. Lophelia pertusa is the most widespread cold-water coral (CWC) species, frequently found in the North Atlantic. Here, we present the first short-term (21 days) data on the effects of increased CO2 (750 ppm) upon the metabolism of freshly collected L. pertusa from Mingulay Reef Complex, Scotland, for comparison with net calcification. Over 21 days, corals exposed to increased CO2 conditions had significantly lower respiration rates (11.4±1.39 SE, μmol O2 g-1 tissue dry weight h-1) than corals in control conditions (28.6±7.30 SE μmol O2 g-1 tissue dry weight h-1). There was no corresponding change in calcification rates between treatments, measured using the alkalinity anomaly technique and 14C uptake. The decrease in respiration rate and maintenance of calcification rate indicates an energetic imbalance, likely facilitated by utilisation of lipid reserves. These data from freshly collected L. pertusa from the Mingulay Reef Complex will help define the impact of ocean acidification upon the growth, physiology and structural integrity of this key reef framework forming species.

  16. Evaluation of the deposition, translocation and pathological response of brake dust with and without added chrysotile in comparison to crocidolite asbestos following short-term inhalation: interim results.

    PubMed

    Bernstein, David M; Rogers, Rick; Sepulveda, Rosalina; Kunzendorf, Peter; Bellmann, Bernd; Ernst, Heinrich; Phillips, James I

    2014-04-01

    Chrysotile has been frequently used in the past in manufacturing brakes and continues to be used in brakes in many countries. This study was designed to provide an understanding of the biokinetics and potential toxicology following inhalation of brake dust following short term exposure in rats. The deposition, translocation and pathological response of brake dust derived from brake pads manufactured with chrysotile were evaluated in comparison to the amphibole, crocidolite asbestos. Rats were exposed by inhalation 6 h/day for 5 days to either brake dust obtained by sanding of brake-drums manufactured with chrysotile, a mixture of chrysotile and the brake dust or crocidolite asbestos. No significant pathological response was observed at any time point in either the brake dust or chrysotile/brake dust exposure groups. The long chrysotile fibers (>20 μm) cleared quickly with T(½) estimated as 30 and 33 days, respectively in the brake dust and the chrysotile/brake dust exposure groups. In contrast, the long crocidolite fibers had a T(½)>1000 days and initiated a rapid inflammatory response in the lung following exposure resulting in a 5-fold increase in fibrotic response within 91 days. These results provide support that brake dust derived from chrysotile containing brake drums would not initiate a pathological response in the lung following short term inhalation.

  17. BWRSAR (Boiling Water Reactor Severe Accident Response) calculations of reactor vessel debris pours for Peach Bottom short-term station blackout

    SciTech Connect

    Hodge, S.A.; Ott, L.J.

    1988-01-01

    This paper describes recent analyses performed by the BWR Severe Accident Technology (BWRSAT) Program at Oak Ridge National Laboratory to estimate the release of debris from the reactor vessel for the unmitigated short-term station blackout accident sequence. Calculations were performed with the BWR Severe Accident Response (BWRSAR) code and are based upon consideration of the Peach Bottom Atomic Power Station. The modeling strategies employed within BWRSAR for debris relocation within the reactor vessel are briefly discussed and the calculated events of the accident sequence, including details of the calculated debris pours, are presented. 4 refs., 13 figs., 3 tabs.

  18. Applications of NASA and NOAA Satellite Observations by NASA's Short-term Prediction Research and Transition (SPoRT) Center in Response to Natural Disasters

    NASA Technical Reports Server (NTRS)

    Molthan, Andrew L.; Burks, Jason E.; McGrath, Kevin M.; Jedlovec, Gary J.

    2012-01-01

    NASA s Short-term Prediction Research and Transition (SPoRT) Center supports the transition of unique NASA and NOAA research activities to the operational weather forecasting community. SPoRT emphasizes real-time analysis and prediction out to 48 hours. SPoRT partners with NOAA s National Weather Service (NWS) Weather Forecast Offices (WFOs) and National Centers to improve current products, demonstrate future satellite capabilities and explore new data assimilation techniques. Recently, the SPoRT Center has been involved in several activities related to disaster response, in collaboration with NOAA s National Weather Service, NASA s Applied Sciences Disasters Program, and other partners.

  19. Virological Response after Short-Term CCR5 Antagonist Exposure in HIV-Infected Patients: Frequency of Subjects with Virological Response and Associated Factors▿

    PubMed Central

    Ruiz-Mateos, Ezequiel; González-Serna, Alejandro; Genebat, Miguel; Machmach, Kawthar; Vidal, Francesc; Muñoz-Fernández, Ángeles; Ferrando-Martinez, Sara; Leal, Manuel

    2011-01-01

    The virological response after an 8-day maraviroc monotherapy has been proposed to be an alternative method to determine whether an CCR5 antagonist should be prescribed to HIV-infected patients. The frequency of patients eligible for a combined antiretroviral therapy which includes maraviroc on the basis of the result of this clinical test is not well-known at the moment. In the same way, clinical and immunovirological factors associated with the virological response after antagonist exposure need to be determined. Ninety consecutive HIV-infected patients were exposed to an 8-day maraviroc monotherapy. The virological response was considered positive if either a reduction of ≥1-log10 HIV RNA copies/ml or an undetectable viral load (<40 HIV RNA copies/ml) was achieved. CXCR4- and CCR5-tropic virus levels were determined by using patients' viral isolates and multiple rounds of infection of indicator cell lines (U87-CXCR4 and U87-CCR5). The frequency of patients with a positive virological response was 72.2% (94.7% and 66.2% for treatment-naïve and pretreated patients, respectively). The positive response rates dramatically decreased in patients with lower CD4+ T-cell counts. The CXCR4-tropic virus level was the only variable independently associated with the virological response after short-term maraviroc exposure. Lower CD4+ T-cell strata were associated with higher CXCR4-tropic virus levels. These results support the suggestion that CCR5 antagonists should be an early treatment option before the expansion of CXCR4-tropic strains. PMID:21807977

  20. Short term response is predictive of long term response to acetylcholinesterase inhibitors in Alzheimer’s disease: A starting point to explore Bayesian approximation in clinical practice

    PubMed Central

    Rota, Eugenia; Ferrero, Patrizia; Ursone, Rita; Migliaretti, Giuseppe

    2007-01-01

    This study was aimed at identifying, in 203 patients with Alzheimer's disease followed during long-term treatment with Acetylcholinesterase inhibitors (ChEIs), the predictive factors of the clinical response among cognition (MMSE), functioning (BADL and IADL) measures and age and gender at the baseline (T0). The ANCOVA test showed a significant association between MMSE scores at time T0 and T3, and the variation T9 to T0, T15 to T0 and T21 to T0 of the MMSE scores, using also gender, age and drug as covariates. The significance was higher for the patients affected by mild dementia. Regarding functional activities, a significant relationship was detected, by the ANCOVA test, only between the scores at T3 and the variation T15 to T0 for BADL, and the variation T9 to T0, T15 to T0 for IADL, respectively. Our results confirm, in a real world setting, that ChEIs provide long-term cognitive benefit, which is correlated to, and predictable by, the short-term response (within the third month) as well as the cognitive status (evaluated by means of the MMSE) at the beginning of the treatment. These factors should be the basis of any cost/effectiveness algorithm in health economic decision models. PMID:18188418

  1. Late Paleocene early Eocene Tethyan carbonate platform evolution — A response to long- and short-term paleoclimatic change

    NASA Astrophysics Data System (ADS)

    Scheibner, C.; Speijer, R. P.

    2008-11-01

    /Eocene Thermal Maximum. The causes for the change from coral-dominated platforms to larger foraminifera-dominated platforms are multilayered. The decline of coralgal reefs in low latitudes during platform stage II is related to overall warming, leading to sea-surface temperatures in the tropics beyond the maximum temperature range of corals. The overall low occurrence of coral reefs in the Paleogene might be related to the presence of a calcite sea. At the same time larger foraminifera started to flourish after their near extinction at the Cretaceous/Paleogene boundary. The demise of coralgal reefs at all studied paleolatitudes in platform stage III can be founded on the effects of the PETM, resulting in short-term warming, eutrophic conditions on the shelves and acidification of the oceans, hampering the growth of aragonitic corals, while calcitic larger foraminifera flourished. In the absence of other successful carbonate-producing organisms, larger foraminifera were able to take over the role as the dominant carbonate platform inhabitant, leading to a stepwise Tethyan platform stage evolution around the Paleocene/Eocene boundary. This szenario might be also effective for threatened coral reef sites.

  2. Down-Regulation of FcεRI-Mediated CD63 Basophil Response during Short-Term VIT Determined Venom-Nonspecific Desensitization

    PubMed Central

    Čelesnik Smodiš, Nina; Šilar, Mira; Eržen, Renato; Rijavec, Matija; Košnik, Mitja; Korošec, Peter

    2014-01-01

    Background We recently showed a desensitization of FcεRI-mediated basophil response after short-term VIT. Our aim was to evaluate the allergen specificity of this desensitization. Methods In 11 Hymenoptera-venom double positive subjects, basophil threshold sensitivity (CD-sens) to anti-FcεRI, honeybee, and Vespula venom was assessed at the beginning and just before the first maintenance dose (MD) of single ultra-rush VIT. In some patients we also monitored CD-sens to rApi m 1 and/or rVes v 5 or other co-sensitizations (i.e., grass pollen). In additional 7 patients, basophils were stripped and sensitized with house dust mite (HDM) IgEs at the same time points. Results We demonstrated a marked reduction of CD-sens to anti-FcεRI and VIT-specific venom before the first MD in all 18 subjects included. Furthermore, in 10 out of 11 double positive subjects, a significant and comparable decrease before the first MD was also evident for non-VIT venom; this nonspecific decrease was further supported by the opposite recombinant species-specific major allergen. In one subject with additional grass pollen allergy, a decrease of CD-sens to grass allergen was also demonstrated. Similarly, in 7 cases of patients with passively HDM-sensitized basophils, a significant reduction of CD-sens was also evident to de novo sensitized HDM allergen. Conclusions Short-term VIT induced basophil desensitization to VIT-specific as well as to VIT-nonspecific venom. As opposed to long-term VIT, which induces venom-specific changes, the effect of short-term VIT seems to be venom-nonspecific. PMID:24733549

  3. The effects of short-term and long-term learning on the responses of lateral intraparietal neurons to visually presented objects.

    PubMed

    Sigurdardottir, Heida M; Sheinberg, David L

    2015-07-01

    The lateral intraparietal area (LIP) is thought to play an important role in the guidance of where to look and pay attention. LIP can also respond selectively to differently shaped objects. We sought to understand to what extent short-term and long-term experience with visual orienting determines the responses of LIP to objects of different shapes. We taught monkeys to arbitrarily associate centrally presented objects of various shapes with orienting either toward or away from a preferred spatial location of a neuron. The training could last for less than a single day or for several months. We found that neural responses to objects are affected by such experience, but that the length of the learning period determines how this neural plasticity manifests. Short-term learning affects neural responses to objects, but these effects are only seen relatively late after visual onset; at this time, the responses to newly learned objects resemble those of familiar objects that share their meaning or arbitrary association. Long-term learning affects the earliest bottom-up responses to visual objects. These responses tend to be greater for objects that have been associated with looking toward, rather than away from, LIP neurons' preferred spatial locations. Responses to objects can nonetheless be distinct, although they have been similarly acted on in the past and will lead to the same orienting behavior in the future. Our results therefore indicate that a complete experience-driven override of LIP object responses may be difficult or impossible. We relate these results to behavioral work on visual attention.

  4. Evaluation of the deposition, translocation and pathological response of brake dust with and without added chrysotile in comparison to crocidolite asbestos following short-term inhalation: Interim results

    SciTech Connect

    Bernstein, David M.; Rogers, Rick; Sepulveda, Rosalina; Kunzendorf, Peter; Bellmann, Bernd; Ernst, Heinrich; Phillips, James I.

    2014-04-01

    Chrysotile has been frequently used in the past in manufacturing brakes and continues to be used in brakes in many countries. This study was designed to provide an understanding of the biokinetics and potential toxicology following inhalation of brake dust following short term exposure in rats. The deposition, translocation and pathological response of brake dust derived from brake pads manufactured with chrysotile were evaluated in comparison to the amphibole, crocidolite asbestos. Rats were exposed by inhalation 6 h/day for 5 days to either brake dust obtained by sanding of brake-drums manufactured with chrysotile, a mixture of chrysotile and the brake dust or crocidolite asbestos. No significant pathological response was observed at any time point in either the brake dust or chrysotile/brake dust exposure groups. The long chrysotile fibers (> 20 μm) cleared quickly with T{sub 1/2} estimated as 30 and 33 days, respectively in the brake dust and the chrysotile/brake dust exposure groups. In contrast, the long crocidolite fibers had a T{sub 1/2} > 1000 days and initiated a rapid inflammatory response in the lung following exposure resulting in a 5-fold increase in fibrotic response within 91 days. These results provide support that brake dust derived from chrysotile containing brake drums would not initiate a pathological response in the lung following short term inhalation. - Highlights: • We evaluated brake dust w/wo added chrysotile in comparison to crocidolite asbestos. • Persistence, translocation, pathological response in the lung and pleural cavity. • Chrysotile cleared rapidly from the lung while the crocidolite asbestos persisted. • No significant pathology observed at any time point in the brake-dust groups. • Crocidolite produced pathological response - Wagner 4 interstitial fibrosis by 32d.

  5. Effect of short-term weight loss on mental stress-induced cardiovascular and pro-inflammatory responses in women.

    PubMed

    Endrighi, Romano; Hamer, Mark; Hackett, Ruth A; Carvalho, Livia A; Jackson, Sarah E; Wardle, Jane; Steptoe, Andrew

    2015-01-01

    Epidemiologic evidence links psychosocial stress with obesity but experimental studies examining the mechanisms that mediates the effect of stress on adiposity are scarce. The aim of this study was to investigate whether changes in adiposity following minimal weight loss affect heightened stress responses in women, and examine the role of the adipokine leptin in driving inflammatory responses. Twenty-three overweight or obese, but otherwise healthy, women (M age = 30.41 ± 8.0 years; BMI = 31.9 ± 4.1 kg/m(2)) completed standardized acute mental stress before and after a 9-week calorie restriction program designed to modify adiposity levels. Cardiovascular (blood pressure and heart rate) and inflammatory cytokines (leptin and interleukin-6; IL-6) responses to mental stress were assessed several times between baseline and a 45-min post-stress recovery period. There were modest changes in adiposity measures while the adipokine leptin was markedly reduced (-27%) after the intervention. Blood pressure reactivity was attenuated (-3.38 ± 1.39 mmHg) and heart rate recovery was improved (2.07 ± 0.96 Bpm) after weight loss. Blood pressure responses were inversely associated with changes in waist to hip ratio post intervention. Decreased levels of circulating leptin following weight loss were inversely associated with the IL-6 inflammatory response to stress (r = -0.47). We offered preliminary evidence suggesting that modest changes in adiposity following a brief caloric restriction program may yield beneficial effect on cardiovascular stress responses. In addition, reductions in basal leptin activity might be important in blunting pro-inflammatory responses. Large randomized trials of the effect of adiposity on autonomic responses are thus warranted.

  6. Induction Chemotherapy with Cisplatin and 5-Fluorouracil in Advanced Head and Neck Cancers: A Short Term Response Evaluation

    PubMed Central

    Rao, Raghavendra; Shenoy, Vijendra; Hegde, Mahesh Chandra; Prasad, Vishnu; Prasad, Krishna

    2015-01-01

    Background Considering the uprising number of Head and neck cancer in the state with limited options of medical and surgical treatment, the focus of this study involved on chemotherapy in advanced Head and neck cancers. The aim of this study was to evaluate the efficacy and toxicity of combination of Cisplatin and 5-Fluorouracil (PF) as induction chemotherapy in patients in locally advanced squamous cell cancer of head and neck. Materials and Methods Forty four patients with previously untreated stage III -IV advanced and inoperable cases were included in this prospective study. Induction chemotherapy consisted of 3 cycles of Cisplatin 100mg/mt2 as infusion on day 1, 5-Fluorouracil of 750mg/mt2 on day 2, 5-Fluorouracil of 1000mg/mt2 as infusion on day 3 in an inpatient basis. Cycles were repeated with an interval of 21 days. Patients were evaluated within a period of 3 weeks at the end of completion of third cycle of chemotherapy. Post chemotherapy local therapy was individualized based on the response, site and stage of the tumour. Results Out of 44 eligible and evaluable patients, major dominance was noted in male group constituting 68%. After induction chemotherapy 58.8% of stage III experienced stable response, & 44% had partial response. In stage IV, 44% showed a stable response and 33.3% had partial response. But in comparison to primary tumour response and nodal response, which had a significant clinical response, the overall response of malignancy with respect to stage and site specificity was clinically insignificant. Moderate adverse reaction was noted in 47.6% and 42.1% had mild reactions. Majority of patients experienced grade 3 adverse events, of which anaemia in females and leucopenia in males pre-dominated. Conclusion With the use of cisplatin and 5-FU as induction chemotherapy agents in advanced and inoperable squamous cell carcinoma of head and neck, a distinct benefit was seen in stabilizing the tumour from progression. But achieving a significant

  7. Global empirical model of TEC response to geomagnetic activity: Short-term (24 hours ahead) prediction model

    NASA Astrophysics Data System (ADS)

    Andonov, Borislav

    2013-04-01

    A global empirical model of the rTEC=(TECobs-TECmed)/TECmed depending on the geomagnetic activity (described by the Kp-index) and at a given moment is built by using global TEC data for full 13 years between 1999 and 2011.The data are downloaded from the CODE (Center for Orbit Determination in Europe) database in the Astronomical Institute, University of Bern. By using a 2D cross-correlation analysis it is found that the ionospheric response to the geomagnetic activity revealed both positive and negative phases of the response. The both phases of the ionospheric response have different duration and time delay with respect to the geomagnetic storm. It was found that these two parameters of the ionospheric response depend on the season, geographical/geomagnetic coordinates and local time. The rTEC response is represented by 2D (longitude-time) sine waves with different zonal wavenumbers and periods being harmonics of the diurnal period. The input data for the current and predicted geomagnetic activity are obtained from the MAK model developed in NIGGG-BAS, which uses the solar wind measurements from the ACE satellite. The background condition is defined by the recent CODE TEC maps. For each current hour the model provides predicted global TEC maps in geographic frame for the next 24 hours.

  8. A model study of the response of mesospheric ozone to short-term solar ultraviolet flux variations

    NASA Technical Reports Server (NTRS)

    Summers, M. E.; Bevilacqua, R. M.; Strobel, D. F.; Zhu, Xun; Deland, M. T.; Allen, M.; Keating, G. M.

    1990-01-01

    An investigation is conducted in order to determine the relative importance of several modeled processes in controlling the magnitude and phase of the mesospheric ozone response. A detailed one-dimensional modeling study of the mesospheric ozone response to solar UV flux variations is conducted to remove some of the deficiencies in previous studies. This study is also used to examine specifically the importance of solar zenith angle, self-consistent calculation of water vapor abundance, and temperature feedback with a nonlocal thermodynamic equilibrium radiation model. The photochemical model is described, and the assumptions made for the purpose of comparing model results with the observed ozone response obtained from a statistical analysis of Solar Mesosphere Explorer data (Keating et al., 1987) are discussed. The numerical results for the theoretical ozone response are presented. The results of selected time-dependent calculations are considered to illustrate the degree to which a relatively simple model of the mesosphere is able to capture the major characteristics of the observed response.

  9. Response of Soil C and N, Dissolved Organic C and N, and Inorganic N to Short-Term Experimental Warming in an Alpine Meadow on the Tibetan Plateau

    PubMed Central

    Yu, Cheng-Qun; Shen, Zhen-Xi; Zhang, Xian-Zhou; Sun, Wei; Fu, Gang

    2014-01-01

    Although alpine meadows of Tibet are expected to be strongly affected by climatic warming, it remains unclear how soil organic C (SOC), total N (TN), ammonium N (NH4+-N) , nitrate N (NO3+-N), and dissolved organic C (DOC) and N (DON) respond to warming. This study aims to investigate the responses of these C and N pools to short-term experimental warming in an alpine meadow of Tibet. A warming experiment using open top chambers was conducted in an alpine meadow at three elevations (i.e., a low (4313 m), mid-(4513 m), and high (4693 m) elevation) in May 2010. Topsoil (0–20 cm depth) samples were collected in July–September 2011. Experimental warming increased soil temperature by ~1–1.4°C but decreased soil moisture by ~0.04 m3 m−3. Experimental warming had little effects on SOC, TN, DOC, and DON, which may be related to lower warming magnitude, the short period of warming treatment, and experimental warming-induced soil drying by decreasing soil microbial activity. Experimental warming decreased significantly inorganic N at the two lower elevations,but had negligible effect at the high elevation. Our findings suggested that the effects of short-term experimental warming on SOC, TN and dissolved organic matter were insignificant, only affecting inorganic forms. PMID:24977179

  10. Response of soil C and N, dissolved organic C and N, and inorganic N to short-term experimental warming in an Alpine meadow on the Tibetan Plateau.

    PubMed

    Yu, Cheng-Qun; Shen, Zhen-Xi; Zhang, Xian-Zhou; Sun, Wei; Fu, Gang

    2014-01-01

    Although alpine meadows of Tibet are expected to be strongly affected by climatic warming, it remains unclear how soil organic C (SOC), total N (TN), ammonium N (NH4 (+)-N) , nitrate N (NO3 (+)-N), and dissolved organic C (DOC) and N (DON) respond to warming. This study aims to investigate the responses of these C and N pools to short-term experimental warming in an alpine meadow of Tibet. A warming experiment using open top chambers was conducted in an alpine meadow at three elevations (i.e., a low (4313 m), mid-(4513 m), and high (4693 m) elevation) in May 2010. Topsoil (0-20 cm depth) samples were collected in July-September 2011. Experimental warming increased soil temperature by ~1-1.4°C but decreased soil moisture by ~0.04 m(3) m(-3). Experimental warming had little effects on SOC, TN, DOC, and DON, which may be related to lower warming magnitude, the short period of warming treatment, and experimental warming-induced soil drying by decreasing soil microbial activity. Experimental warming decreased significantly inorganic N at the two lower elevations,but had negligible effect at the high elevation. Our findings suggested that the effects of short-term experimental warming on SOC, TN and dissolved organic matter were insignificant, only affecting inorganic forms.

  11. [Short-term response of soil CH4 flux to simulated precipitation in a winter wheat field on the Loess Plateau, Northwest China].

    PubMed

    Liu, Quan-quan; Wang, Jun; Chen, Rong-rong; Liu, Wen-zhao; Sainju, Upendra M

    2015-01-01

    To understand the short-term response of soil CH4 flux to different precipitation events in a winter wheat field on the Loess Plateau, we conducted precipitation simulation experiments during winter wheat jointing stage and summer fallow period to measure the soil CH4 flux in 0 to 72 h after precipitation simulation of 1 to 32 mm. Results showed that CH4 flux during 0 to 72 h fluctuated at 1 to 8 mm of precipitation application and peaked at 16 and 32 mm. Cumulative CH4 flux after 72 h of precipitation (CH4-C) increased linearly with the precipitation amount (P) (wheat jointing stage: CH-C=2.45P-6.09, R2=0.92, P<0.01; summer fallow: CH-C=2.43P-4.73, R2 = 0.91, P<0.01). Statistical analysis showed that CH4 flux was also correlated with soil water content and microbial biomass carbon but not with soil temperature. In the long run, small precipitation events (1-8 mm) could enhance the intensity of soil CH4 sink and such promoting effect would be weakened with further increase in precipitation amount. However, large precipitation events (≥16 mm) could change the soil function from CH4 sink to source by stimulating the activity of soil methanogens during short-term periods.

  12. Correlation of the Virological Response to Short-Term Maraviroc Monotherapy with Standard and Deep-Sequencing-Based Genotypic Tropism Prediction Methods

    PubMed Central

    Gonzalez-Serna, A.; McGovern, R. A.; Harrigan, P. R.; Vidal, F.; Poon, A. F. Y.; Ferrando-Martinez, S.; Abad, M. A.; Genebat, M.; Leal, M.

    2012-01-01

    Genotypic tropism testing methods are emerging as the first step before prescription of the CCR5 antagonist maraviroc (MVC) to HIV-infected patients in Europe. Studies validating genotypic tests have included other active drugs that could have potentially convoluted the effects of MVC. The maraviroc clinical test (MCT) is an in vivo drug sensitivity test based on the virological response to a short-term exposure to MVC monotherapy. Thus, our aim was to compare the results of genotypic tropism testing methods with the short-term virological response to MVC monotherapy. A virological response in the MCT was defined as a ≥1-log10 decrease in HIV RNA or undetectability after 8 days of drug exposure. Seventy-three patients undergoing the MCT were included in this study. We used both standard genotypic methods (n = 73) and deep sequencing (n = 27) on MCT samples at baseline. For the standard methods, the most widely used genotypic algorithms for analyzing the V3 loop sequence, geno2pheno and PSSM, were used. For deep sequencing, the geno2pheno algorithm was used with a false-positive rate cutoff of 3.5. The discordance rates between the standard genotypic methods and the virological response were approximately 20% (including mostly patients without a virological response). Interestingly, these discordance rates were similar to that obtained from deep sequencing (18.5%). The discordance rates between the genotypic methods (tropism assays predictive of the use of the CCR5 coreceptor) and the MCT (in vivo MVC sensitivity assay) indicate that the algorithms used by genotypic methods are still not sufficiently optimized. PMID:22143533

  13. Short-term soil responses to late-seeded cover crops in a semi-arid environment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cover crops can expand ecosystem services, though sound management recommendations for their use within semi-arid cropping systems is currently constrained by a lack of information. This study was conducted to determine agroecosystem responses to late-summer seeded cover crops under no-till managem...

  14. Efficacy of metomidate and tricaine methanesulfonate to modulate the short-term cortisol stress response in channel catfish Ictalurus punctatus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ability of the anesthetics metomidate and tricaine methanesulfonate to mitigate the cortisol stress response of channel catfish Ictalurus punctatus was evaluated during a 10 min confinement stress. Channel catfish (11.9 ± 0.5 g; mean ± SE) were transferred from holding tanks to confinement buck...

  15. Short term supplementation of dietary antioxidants selectively regulates the inflammatory responses during early cutaneous wound healing in diabetic mice

    PubMed Central

    2011-01-01

    Background Diabetic foot ulcers are serious complications for diabetic patients, yet the precise mechanism that underlines the treatment of these diabetic complications remains unclear. We hypothesized that dietary antioxidant supplementation with vitamin C, combined either with vitamin E or with vitamin E and NAC, improves delayed wound healing through modulation of blood glucose levels, oxidative stress, and inflammatory response. Methods Diabetes was induced by administration of alloxan monohydrate. Mice were divided into 4 groups; CON (non-diabetic control mice fed AIN 93 G purified rodent diet), DM (diabetic mice fed AIN 93 G purified rodent diet), VCE (diabetic mice fed 0.5% vitamin C and 0.5% vitamin E supplemented diet), and Comb (diabetic mice fed 0.5% vitamin C, 0.5% vitamin E, and 2.5% NAC supplemented diet). After 10 days of dietary antioxidant supplementation, cutaneous full-thickness excisional wounds were performed, and the rate of wound closure was examined. TBARS as lipid peroxidation products and vitamin E levels were measured in the liver. Expression levels of oxidative stress and inflammatory response related proteins were measured in the cutaneous wound site. Results Dietary antioxidant supplementation improved blood glucose levels and wound closure rate and increased liver vitamin E, but not liver TBARS levels in the diabetic mice as compared to those of the CON. In addition, dietary antioxidant supplementation modulated the expression levels of pIκBα, HO-1, CuZnSOD, iNOS and COX-2 proteins in the diabetic mice. Conclusions These findings demonstrated that delayed wound healing is associated with an inflammatory response induced by hyperglycaemia, and suggests that dietary antioxidant supplementation may have beneficial effects on wound healing through selective modulation of blood glucose levels, oxidative stress, and inflammatory response. PMID:22088091

  16. Aerobic fitness and sympatho-adrenal response to short-term psycho-emotional stress under field conditions.

    PubMed

    Wittels, P; Rosenmayr, G; Bischof, B; Hartter, E; Haber, P

    1994-01-01

    A possible relationship between aerobic fitness (AF), measured by maximal cycle ergometry (CE) and sympatho-adrenal response to acute, short lasting psycho-emotional stress was investigated by monitoring heart rate (fc) and excretion of catecholamines. The activation of the sympatho-adrenal system was characterised by the noradrenaline: adrenaline ratio. A group of 11 healthy men [22.8 (SD 2.52) years] lived under identical environmental conditions; their mean maximal oxygen uptake (VO2max) was 47.1 (SD 3.9) ml.min-1.kg-1. After the physiological and psychological laboratory tests had been completed the fc of the subjects was monitored continuously during the "guerilla slide" and "parachute jump by night", two emotionally stressful military tasks. Maximal fc (fc, max) attained during these events was 84.5% and 83% of fc, max during CE (fc, max, CE), respectively. A significant relationship (r = -0.92, P < 0.0002) between fc, max reached during the stressful tasks and VO2max was found only for the guerilla slide, which was preceded by physical strain, sleep deprivation and energy deficit. One subject with some prior experience in parachuting showed the lowest fc response and the lowest sympatho-adrenal activation in both events, independent of the degree of AF. In conclusion, AF was found to influence the sympatho-adrenal and fc response to acute, short-lasting emotional stress when the stressful event was aggravated by preceding physical strain, the magnitude of the stress response depending largely on individual experience and effective mechanisms for coping with specific stimuli.

  17. Short-term response of songbirds to experimental thinning of young Douglas-fir forests in the Oregon Cascades

    USGS Publications Warehouse

    Hagar, Joan C.; Howlin, Shay; Ganio, L.

    2004-01-01

    Commercial thinning has the potential to increase structural diversity in managed conifer stands and redirect development of young stands towards structure characteristic of late-seral habitats. Thinning to increase diversity, however, is likely to require different strategies than thinning to maximize timber production. To prescribe thinning regimes that will promote diversity, managers need more information on response of wildlife to a range of thinning intensities and patterns. We studied the response of forest songbirds to three different intensities and patterns of thinning in 40-year-old stands dominated by Douglas-fir (Pseudotsuga menziesii) in the Oregon Cascades. We estimated densities of songbirds for 2 years before and 4 years after experimental thinning with standard point count methodology. We compared changes in density before and after thinning between each thinning treatment and the control with repeated measures analysis of variance. Thinning increased species richness and the density of 10 species. Furthermore, the frequency of detection of four additional species increased in thinned stands. Thinning decreased the density of five species, but no species was excluded by thinning. Our results were largely consistent with those from other studies of bird response to thinning from different regions of the Pacific Northwest. We conclude that commercial thinning rapidly promotes diversity of breeding songbirds in young, conifer-dominated stands. However, we suggest using a variety of thinning intensities and patterns, ranging from no thinning to very widely spaced residual trees, in order to maximize avian diversity at the landscape scale and structural diversity both within and among stands.

  18. Time-series integrated "omic" analyses to elucidate short-term stress-induced responses in plant liquid cultures.

    PubMed

    Dutta, Bhaskar; Kanani, Harin; Quackenbush, John; Klapa, Maria I

    2009-01-01

    The research that aims at furthering our understanding of plant primary metabolism has intensified during the last decade. The presented study validated a systems biology methodological framework for the analysis of stress-induced molecular interaction networks in the context of plant primary metabolism, as these are expressed during the first hours of the stress treatment. The framework involves the application of time-series integrated full-genome transcriptomic and polar metabolomic analyses on plant liquid cultures. The latter were selected as the model system for this type of analysis, because they provide a well-controlled growth environment, ensuring that the observed plant response is due only to the applied perturbation. An enhanced gas chromatography-mass spectrometry (GC-MS) metabolomic data correction strategy and a new algorithm for the significance analysis of time-series "omic" data are used to extract information about the plant's transcriptional and metabolic response to the applied stress from the acquired datasets; in this article, it is the first time that these are applied for the analysis of a large biological dataset from a complex eukaryotic system. The case-study involved Arabidopsis thaliana liquid cultures subjected for 30 h to elevated (1%) CO2 stress. The advantages and validity of the methodological framework are discussed in the context of the known A. thaliana or plant, in general, physiology under the particular stress. Of note, the ability of the methodology to capture dynamic aspects of the observed molecular response allowed for 9 and 24 h of treatment to be indicated as corresponding to shifts in both the transcriptional and metabolic activity; analysis of the pathways through which these activity changes are manifested provides insight to regulatory processes.

  19. Effects of biochar addition on greenhouse gas emissions and microbial responses in a short-term laboratory experiment.

    PubMed

    Yoo, Gayoung; Kang, Hojeong

    2012-01-01

    Biochar application to soil has drawn much attention as a strategy to sequester atmospheric carbon in soil ecosystems. The applicability of this strategy as a climate change mitigation option is limited by our understanding of the mechanisms responsible for the observed changes in greenhouse gas emissions from soils, microbial responses, and soil fertility changes. We conducted an 8-wk laboratory incubation using soils from PASTURE (silt loam) and RICE PADDY (silt loam) sites with and without two types of biochar (biochar from swine manure [CHAR-M] and from barley stover [CHAR-B]). Responses to addition of the different biochars varied with the soil source. Addition of CHAR-B did not change CO and CH evolution from the PASTURE or the RICE PADDY soils, but there was a decrease in NO emissions from the PASTURE soil. The effects of CHAR-M addition on greenhouse gas emissions were different for the soils. The most substantial change was an increase in NO emissions from the RICE PADDY soil. This result was attributed to a combination of abundant denitrifiers in this soil and increased net nitrogen mineralization. Soil phosphatase and N-acetylglucosaminidase activity in the CHAR-B-treated soils was enhanced compared with the controls for both soils. Fungal biomass was higher in the CHAR-B-treated RICE PADDY soil. From our results, we suggest CHAR-B to be an appropriate amendment for the PASTURE and RICE PADDY soils because it provides increased nitrogen availability and microbial activity with no net increase in greenhouse gas emissions. Application of CHAR-M to RICE PADDY soils could result in excess nitrogen availability, which may increase NO emissions and possible NO leaching problems. Thus, this study confirms that the ability of environmentally sound biochar additions to sequester carbon in soils depends on the characteristics of the receiving soil as well as the nature of the biochar.

  20. Value of intravoxel incoherent motion and dynamic contrast-enhanced MRI for predicting the early and short-term responses to chemoradiotherapy in nasopharyngeal carcinoma

    PubMed Central

    Hou, Jing; Yu, Xiaoping; Hu, Yin; Li, Feiping; Xiang, Wang; Wang, Lanlan; Wang, Hui; Lu, Qiang; Zhang, Zhongping; Zeng, Wenbin

    2016-01-01

    Abstract The aim of the study was to investigate the value of intravoxel incoherent motion diffusion-weighted magnetic resonance imaging (IVIM-DWI) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in predicting the early and short-term responses to chemoradiotherapy (CRT) in patients with nasopharyngeal carcinoma (NPC). Forty-three NPC patients underwent IVIM-DWI and DCE-MRI at baseline (pretreatment) and after the first cycle of induction chemotherapy (posttreatment). Based on whether locoregional lesions were identified, patients were divided into the residual and nonresidual groups at the end of CRT and into the good-responder and poor-responder groups 6 months after the end of CRT. The pretreatment and posttreatment IVIM-DWI parameters (ADC, D, D∗, and f) and DCE-MRI parameters (Ktrans, Kep, and Ve) values and their percentage changes (Δ%) were compared between the residual and nonresidual groups and between the good-responder and poor-responder groups. None of perfusion-related parametric values derived from either DCE-MRI or IVIM-DWI showed significant differences either between the residual and nonresidual groups or between the good-responder and poor-responder groups. The nonresidual group exhibited lower pre-ADC, lower pre-D, and higher Δ%D values than did the residual group (all P <0.05). The good-responder group had lower pre-D and pre-ADC values than did the poor-responder group (both P <0.05). Based on receiver operating characteristic (ROC) curve analysis, pre-D had the highest area under the curve in predicting both the early and short-term responses to CRT for NPC patients (0.817 and 0.854, respectively). IVIM-DWI is more valuable than DCE-MRI in predicting the early and short-term response to CRT for NPC, and furthermore diffusion-related IVIM-DWI parameters (pre-ADC, pre-D, and Δ%D) are more powerful than perfusion-related parameters derived from both IVIM-DWI and DCE-MRI. PMID:27583847

  1. Photosynthetic Response to Long- and Short-Term Changes in Carbon Dioxide in Sweetpotatoes Grown Hydroponically with Enhanced Mineral Nutrition

    NASA Technical Reports Server (NTRS)

    Hamilton, Casey; Terse, Anita; Hileman, Douglas R.; Mortley, Desmond G.; Hill, Jill

    1998-01-01

    Sweetpotato [Ipomoea batatas L.(Lam.)] has been selected by NASA as a potential food for long-term space missions. In previous experiments, sweetpotato plants grown hydroponically under elevated levels of CO2 depleted the nitrogen in the nutrient solution between the hi-weekly solution replacements. In this experiment, the effect of enhanced nutrient replenishment on photosynthetic rates of sweetpotato was determined. CO2 response curves were determined for "TU-82-155" and "Georgia-Jet" sweetpotatoes grown hydroponically in growth chambers at three different CO2 concentrations (400, 750, and 1000 micro-mol/mol CO2). Gas exchange measurements were made using infrared gas analysis, an open-flow gas exchange system, and a controlled-climate cuvette. Photosynthetic measurements were made at CO2 concentrations from 50-1000 micro-mol/mol CO2. Net photosynthetic rates showed an increase with increasing measurement CO2 in all nutrient regimes, but the response of photosynthetic rates to the growth CO2 conditions varied among the experiments and between the two varieties. Enhanced mineral nutrition led to increased net photosynthetic rates in "Georgia Jet" plants, but not in "TU-82-155" plants. The results of this study will help to determine the CO2 requirements for growth of sweetpotato on proposed space missions.

  2. Comparison of the short-term oxidative stress response in National League basketball and soccer adolescent athletes.

    PubMed

    Perrea, Anastasia; Vlachos, Ioannis S; Korou, Laskarina-Maria; Doulamis, Ilias P; Exarhopoulou, Konstantina; Kypraios, George; Kalofoutis, Anastasios; Perrea, Despina N

    2014-08-01

    Physical exercise is considered protective against oxidative stress-related disorders. However, there is increasing evidence that strenuous activity may induce increased oxidative stress response. This study investigated the impact of vigorous physical activity on serum oxidative stress markers in 36 soccer and 12 basketball National League adolescent athletes 40 minutes before and 15 minutes after a National League game. Serum total peroxide, fibrinogen, polymorphonuclear (PMN) elastase, and myeloperoxidase levels were determined. No significant differences in any of the measured parameters were observed before the match. Soccer players exhibited significantly lower total peroxide (P < .05) and higher PMN elastase concentrations (P < .05) than that of the basketball athletes after the game. A number of important differences between these 2 sports, such as duration or total aerobic and anaerobic demands, may affect oxidative status. These parameters need to be further examined in order to elucidate the different effects of these 2 sports on postexercise oxidative status.

  3. Short-term variation in labelling index as a predictor of radiotherapy response in human oral cavity carcinoma

    SciTech Connect

    Silvestrini, R.; Molinari, R.; Costa, A.; Volterrani, F.; Gardani, G.

    1984-07-01

    In vitro determination of (/sup 3/H)thymidine labeling index (LI) was carried out on squamous cell carcinomas of the oral cavity from 52 patients before and during radiotherapy. Pretreatment LI values ranged from 0.01% to 50%. After administration of the first 10 Gy in five consecutive daily fractions, a decrease in LI was observed in 39 cases and an enhancement in 13 cases, with an overall median 70% decrease in the initial value. The type of variation induced by radiotherapy was not related to pretreatment LI except for tumors with a very low proliferative activity, which all showed a marked increase in LI. Pretreatment LI was not indicative of short- or long-term response to radiotherapy, whereas the variation induced on LI after 10 Gy was related to the clinical outcome.

  4. Short-term blackcurrant extract consumption modulates exercise-induced oxidative stress and lipopolysaccharide-stimulated inflammatory responses.

    PubMed

    Lyall, K A; Hurst, S M; Cooney, J; Jensen, D; Lo, K; Hurst, R D; Stevenson, L M

    2009-07-01

    Exercise-induced oxidative stress is instrumental in achieving the health benefits from regular exercise. Therefore, inappropriate use of fruit-derived products (commonly applied as prophalytic antioxidants) may counteract the positive effects of exercise. Using human exercise and cellular models we found that 1) blackcurrant supplementation suppressed exercise-induced oxidative stress, e.g., plasma carbonyls (0.9 +/- 0.1 vs. 0.6 +/- 0.1 nmol/mg protein, placebo vs. blackcurrant), and 2) preincubation of THP-1 cells with an anthocyanin-rich blackcurrant extract inhibited LPS-stimulated cytokine secretion [TNF-alpha (16,453 +/- 322 vs. 10,941 +/- 82 pg/ml, control vs. extract, P < 0.05) and IL-6 (476 +/- 14 vs. 326 +/- 32 pg/ml, control vs. extract, P < 0.05)] and NF-kappaB activation. In addition to its antioxidant and anti-inflammatory properties, we found that postexercise plasma collected after blackcurrant supplementation enhanced the differential temporal LPS-stimulated inflammatory response in THP-1 cells, resulting in an early suppression of TNF-alpha (1,741 +/- 32 vs. 1,312 +/- 42 pg/ml, placebo vs. blackcurrant, P < 0.05) and IL-6 (44 +/- 5 vs. 36 +/- 3 pg/ml, placebo vs. blackcurrant, P < 0.05) secretion after 24 h. Furthermore, by using an oxidative stress cell model, we found that preincubation of THP-1 cells with hydrogen peroxide (H(2)O(2)) prior to extract exposure caused a greater suppression of LPS-stimulated cytokine secretion after 24 h, which was not evident when cells were simultaneously incubated with H(2)O(2) and the extract. In summary, our findings support the concept that consumption of blackcurrant anthocyanins alleviate oxidative stress, and may, if given at the appropriate amount and time, complement the ability of exercise to enhance immune responsiveness to potential pathogens.

  5. Proteomic analysis of salt-responsive proteins in the leaves of mangrove Kandelia candel during short-term stress.

    PubMed

    Wang, Lingxia; Liu, Xiao; Liang, Meng; Tan, Fanglin; Liang, Wenyu; Chen, Yiyong; Lin, Yongxiang; Huang, Li; Xing, Jianhong; Chen, Wei

    2014-01-01

    Salt stress is a major abiotic stress that limits crop productivity in many regions of the world. A comparative proteomic approach to identify salt stress-responsive proteins and to understand the molecular mechanisms was carried out in the woody halophyte Kandelia candel. Four-leaf-old K. candel seedlings were exposed to 150 (control), 300, 450, and 600 mM NaCl for 3 days. Proteins extracted from the leaves of K. candel seedlings were separated by two-dimensional gel electrophoresis (2-DE). More than 900 protein spots were detected on each gel, and 53 differentially expressed protein spots were located with at least two-fold differences in abundance on 2-DE maps, of which 48 were identified by matrix-assisted laser desorption ionization time-of-flight/time-of-flight mass spectrometry (MALDI-TOF-TOF/MS). The results showed that K. candel could withstand up to 450 mM NaCl stress by up-regulating proteins that are mainly involved in photosynthesis, respiration and energy metabolism, Na(+) compartmentalization, protein folding and assembly, and signal transduction. Physiological data, including superoxide dismutase (SOD) and dehydroascorbate reductase (DHAR) activities, hydrogen peroxide (H2O2) and superoxide anion radicals (O2(-)) contents, as well as Na(+) content and K(+)/Na(+) ratios all correlated well with our proteomic results. This study provides new global insights into woody halophyte salt stress responses. Identification of differentially expressed proteins promotes better understanding of the molecular basis for salt stress reduction in K. candel.

  6. Proteomic Analysis of Salt-Responsive Proteins in the Leaves of Mangrove Kandelia candel during Short-Term Stress

    PubMed Central

    Liang, Meng; Tan, Fanglin; Liang, Wenyu; Chen, Yiyong; Lin, Yongxiang; Huang, Li; Xing, Jianhong; Chen, Wei

    2014-01-01

    Salt stress is a major abiotic stress that limits crop productivity in many regions of the world. A comparative proteomic approach to identify salt stress-responsive proteins and to understand the molecular mechanisms was carried out in the woody halophyte Kandelia candel. Four-leaf-old K. candel seedlings were exposed to 150 (control), 300, 450, and 600 mM NaCl for 3 days. Proteins extracted from the leaves of K. candel seedlings were separated by two-dimensional gel electrophoresis (2-DE). More than 900 protein spots were detected on each gel, and 53 differentially expressed protein spots were located with at least two-fold differences in abundance on 2-DE maps, of which 48 were identified by matrix-assisted laser desorption ionization time-of-flight/time-of-flight mass spectrometry (MALDI-TOF-TOF/MS). The results showed that K. candel could withstand up to 450 mM NaCl stress by up-regulating proteins that are mainly involved in photosynthesis, respiration and energy metabolism, Na+ compartmentalization, protein folding and assembly, and signal transduction. Physiological data, including superoxide dismutase (SOD) and dehydroascorbate reductase (DHAR) activities, hydrogen peroxide (H2O2) and superoxide anion radicals (O2−) contents, as well as Na+ content and K+/Na+ ratios all correlated well with our proteomic results. This study provides new global insights into woody halophyte salt stress responses. Identification of differentially expressed proteins promotes better understanding of the molecular basis for salt stress reduction in K. candel. PMID:24416157

  7. Impact of short-term heat stress on physiological responses and expression profile of HSPs in Barbari goats

    NASA Astrophysics Data System (ADS)

    Dangi, Satyaveer Singh; Gupta, Mahesh; Nagar, Vimla; Yadav, Vijay Pratap; Dangi, Saroj K.; Shankar, Om; Chouhan, Vikrant Singh; Kumar, Puneet; Singh, Gyanendra; Sarkar, Mihir

    2014-12-01

    Six, nonpregnant, Barbari goats aged 4-5 years were selected for the study. For the first 6 days, the animals were kept in psychrometric chamber at thermoneutral temperature for 6 h each day to make them acclimated to climatic chamber. On the 7th day, the animals were exposed to 41 °C temperature for 3 h and then to 45 °C for the next 3 h. Cardinal physiological responses were measured, and blood samples (3 ml) were collected at 1-h interval during the heat exposure period and then once after 6 h of the heat exposure. The rectal temperature (RT) and respiratory rate (RR) increased significantly ( P < 0.05) during the heat exposure compared to pre- and postexposure. The relative messenger RNA (mRNA) expression of heat shock protein (HSP)60, HSP70, and HSP90 increased significantly ( P < 0.05) within 1 h after exposure to heat stress at 41 and 45 °C and decreased significantly ( P < 0.05) in next 2 h but remain significantly ( P < 0.05) elevated from preexposure. HSP105/110 relative mRNA expression level remained unchanged during the first 4 h, and thereafter, it increased significantly ( P < 0.05) and reached the peak at 6 h. Relative protein expression pattern of HSPs during exposure to heat stress showed similar trend as observed for the relative mRNA expression. Given the response sensitivity and intensity of HSP genes to environmental stresses, HSP70 was found to be the most sensitive to temperature fluctuation, and it could be used as an important molecular biomarker to heat stress in animals.

  8. A short term response of the ecogeomorphological system under hydric stress situations along a mediterranean pluviometric gradient.

    NASA Astrophysics Data System (ADS)

    Ruiz Sinoga, J. D.; Ferre Bueno, E.; Martinez Murillo, J. F.; Gabarron Galeote, M. A.

    2009-04-01

    Many studies have shown the variable response of the ecomorphological system along a pluviometric gradient, which from a functional point of view, may be summed up as an impoverishment of the relationship soil-water-plant. In the present study, taking such a spatial variability change as our starting point, have been analysed the adaptation of the different integral parameters of the ecogeomorphological system to a hydric stress situation. The area under study is southern Spain, where have been established a pluviometric gradient on 3 experimental hillslopes, Colmenar (668 mm/y-1), Almogía (514 mm/y-1) y Berja (308 mm/y-1). On each of the hillslopes were established an experimental plot open from top to bottom 5 metres wide, which was monitored for four years (September 2002 to September 2006): the rainfall with a totalizator rain gauge, the water content of the soil in fixed sampling points situated every 10 m. from top to bottom by means of TDR probes, (Tektronix 1502C) both on the surface and at a depth of 15cm., the physico-chemical soil properties by analysing disturbed and undisturbed samples at the same measuring points for soil moisture, vegetation cover and the number of plants by photographing them at a height of 5 m. using a high resolution digital camera. By carrying out our observation during a period of drought 2004-2006 were able to analyse its effect on the parameters which make up the ecogeomorphological system of each of the hillslopes. The objectives of the present study were: i) to determine the inter-annual variability of the soil water content and the available water for vegetation, and ii) to analyse the response, the adaptation and the degree of vulnerability of the remaining elements in the ecogeomorphological system, vegetation and soil, to a situation of hydric stress, as happened between 2004-2006 in southern Spain. The results obtained showed that: i) as is characteristic of Mediterranean environments the soil moisture is very variable

  9. Ghrelin response to hedonic eating in underweight and short-term weight restored patients with anorexia nervosa.

    PubMed

    Maria Monteleone, Alessio; Monteleone, Palmiero; Dalle Grave, Riccardo; Nigro, Massimiliano; El Ghoch, Marwan; Calugi, Simona; Cimino, Monica; Maj, Mario

    2016-01-30

    Recently, anorexia nervosa (AN) has been conceptualized as a reward-related disorder, and alterations in brain reward processes have been documented in both acute and recovered AN patients. However, the role of endogenous biochemical mediators, such as ghrelin, in the modulation of reward processes has been poorly investigated in this eating disorder. Hedonic eating, that is the consumption of food exclusively for pleasure and not to maintain energy homeostasis, is a useful paradigm to investigate the physiology of food-related reward. Therefore, we assessed the response of peripheral ghrelin to hedonic eating in 7 underweight and 7 recently weight-restored AN patients and compared it to that of previously studied healthy controls. We found that in satiated underweight patients with AN plasma ghrelin levels progressively decreased after the exposure and the consumption of both the favorite and unfavorite food whereas in satiated weight-restored AN patients and satiated healthy controls plasma ghrelin concentrations significantly increased after the exposure to the favorite food and after eating it, but decreased after the unfavorite food. These results suggest a derangement in the ghrelin modulation of food-related pleasurable and rewarding feelings, which might sustain the reduced motivation toward food intake of acute AN patients.

  10. Assessment of DNA damage and molecular responses in Labeo rohita (Hamilton, 1822) following short-term exposure to silver nanoparticles.

    PubMed

    Sharma, Niti; Rather, Mohd Ashraf; Ajima, Malachy N O; Gireesh-Babu, P; Kumar, Kundan; Sharma, Rupam

    2016-10-01

    The increasing application of silver nanoparticles (Ag-NPs) both in industries and in agricultural fields has led to its accumulation in the aquatic ecosystem through water run-off. In the present study, the effects of Ag-NPs in the liver of Labeo rohita, were investigated at genomic and cellular level for seven days at the concentrations of 100, 200, 400 and 800 μg l(-1) by using 18 and 29 nm sizes of Ag-NPs. The Ag-NPs sizes of 18 and 29 nm were synthesized by a chemical method using atomic force microscopy with the zeta potential of -55 mV and-31.4 mV respectively. They were found to be spherical with smooth surfaces. Assessment of genotoxic effects of the particles in the fish using single-cell gel electrophoresis showed DNA damage on exposure to concentrations of 400 and 800 μg l(-1). Histopathological examination of the liver revealed vacuolar degeneration, hepatocytes have undergone total degeneration and high accumulation of Ag-NPs that depicted both time and dose-dependent relationships. Furthermore, the expression study of stress-related genes showed down-regulation, due to the production of free radicals and reactive oxygen species. Ag-NPs can cause both DNA damage and affect the cellular responses of L. rohita.

  11. Short-term soil loss by eolian erosion in response to different rain-fed agricultural practices

    NASA Astrophysics Data System (ADS)

    Tanner, Smadar; Katra, Itzhak; Zaady, Eli

    2016-04-01

    Eolian (wind) erosion is a widespread process and a major form of soil degradation in arid and semi-arid regions. The present study examined changes in soil properties and eolian soil loss at a field scale in response to different soil treatments in two rain-fed agricultural practices. Field experiments with a boundary-layer wind tunnel and soil analysis were used to obtain the data. Two practices with different soil treatments (after harvest), mechanical tillage and stubble grazing intensities, were applied in the fallow phase of the rotation (dry season). The mechanical tillage and the stubble grazing had an immediate and direct effects on soil aggregation but not on the soil texture, and the contents of soil water, organic matter, and CaCO3. Higher erosion rates, that was measured as fluxes of total eolian sediment and particulate matter <10 μm (PM10), were recorded under mechanical tillage and grazing intensities compared with the undisturbed topsoil of the control plots. The erosion rates were higher in grazing plots than in tillage plots. The calculated soil fluxes in this study indicate potentially rapid soil degradation due to loss of fine particles by wind. The finding may have implications for long-term management of agricultural soils in semi-arid areas.

  12. A snap shot of the short-term response of crustaceans to macrophyte detritus in the deep Oslofjord

    NASA Astrophysics Data System (ADS)

    Ramirez-Llodra, Eva; Rinde, Eli; Gundersen, Hege; Christie, Hartvig; Fagerli, Camilla With; Fredriksen, Stein; Gitmark, Janne Kim; Norling, Karl; Walday, Mats Gunnar; Norderhaug, Kjell Magnus

    2016-03-01

    A test deployment of a time-lapse camera lander in the deep Oslofjord (431 m) was used to obtain initial information on the response of benthic fauna to macroalgal debris. Three macroalgal species were used on the lander baited plate: Fucus serratus, Saccharina latissima and Laminaria hyperborea and observed during 41.5 hours. The deep-water shrimp Pandalus borealis were attracted to the macroalgae rapidly (3 min after the lander reached the seafloor), followed by amphipods. Shrimp abundances were significantly higher in areas covered by macroalgae compared to the adjacent seafloor and the number of shrimp visiting the macroalgae increased with time. Amphipods arrived 13 hours later and were observed mainly on decaying L. hyperborea. The abundance of amphipods on L. hyperborea increased rapidly, reaching a peak at 31 h after deployment. These initial observations suggest that debris from kelp forests and other macroalgal beds may play an important role in fuelling deep benthic communities in the outer Oslofjord and, potentially, enhance secondary production of commercial species such as P. borealis.

  13. Effects of short-term hypoxia and seawater acidification on hemocyte responses of the mussel Mytilus coruscus.

    PubMed

    Sui, Yanming; Kong, Hui; Shang, Yueyong; Huang, Xizhi; Wu, FangLi; Hu, Menghong; Lin, Daohui; Lu, Weiqun; Wang, Youji

    2016-07-15

    Hypoxia often intensifies with rising dissolved CO2, but the concurrent effects of hypoxia and acidification on bivalves are largely unknown. In this study, immune responses of hemocytes in the mussel Mytilus coruscus were examined under six combinations of pH (7.3, 7.7 and 8.1) and dissolved oxygen (DO) concentrations (2mgL(-1), 6mgL(-1)) for 72h. Generally, total hemocyte account, phagocytosis, esterase and lysosomal content were reduced under low DO and pH conditions, whereas hemocyte mortality and reactive oxygen species production increased under low DO and pH. Both hypoxia and low pH have negative effects on mussels, but the effects of pH are not as strong as DO. Moreover, significant interactions between DO and pH occurred. However, acidification generally doesn't aggravate the effects induced by hypoxia. Acidification and hypoxia may increase disease risk and impact the aquaculture of this species.

  14. A snap shot of the short-term response of crustaceans to macrophyte detritus in the deep Oslofjord

    PubMed Central

    Ramirez-Llodra, Eva; Rinde, Eli; Gundersen, Hege; Christie, Hartvig; Fagerli, Camilla With; Fredriksen, Stein; Gitmark, Janne Kim; Norling, Karl; Walday, Mats Gunnar; Norderhaug, Kjell Magnus

    2016-01-01

    A test deployment of a time-lapse camera lander in the deep Oslofjord (431 m) was used to obtain initial information on the response of benthic fauna to macroalgal debris. Three macroalgal species were used on the lander baited plate: Fucus serratus, Saccharina latissima and Laminaria hyperborea and observed during 41.5 hours. The deep-water shrimp Pandalus borealis were attracted to the macroalgae rapidly (3 min after the lander reached the seafloor), followed by amphipods. Shrimp abundances were significantly higher in areas covered by macroalgae compared to the adjacent seafloor and the number of shrimp visiting the macroalgae increased with time. Amphipods arrived 13 hours later and were observed mainly on decaying L. hyperborea. The abundance of amphipods on L. hyperborea increased rapidly, reaching a peak at 31 h after deployment. These initial observations suggest that debris from kelp forests and other macroalgal beds may play an important role in fuelling deep benthic communities in the outer Oslofjord and, potentially, enhance secondary production of commercial species such as P. borealis. PMID:27025314

  15. Organ specific antioxidant responses in golden grey mullet (Liza aurata) following a short-term exposure to phenanthrene.

    PubMed

    Oliveira, M; Pacheco, M; Santos, M A

    2008-06-15

    Phenanthrene (Phe) is among the most abundant and ubiquitous polycyclic aromatic hydrocarbons (PAHs) in the aquatic environment as a result of human activities. Even so, the knowledge about its impact on fish health is still limited. In this study, the teleost Liza aurata was exposed to 0.1, 0.3, 0.9 and 2.7 microM Phe concentrations during 16 h. Enzymatic antioxidants such as selenium dependent glutathione peroxidase (GPx), glutathione S-transferase (GST), glutathione reductase (GR) and catalase (CAT), as well as a non-enzymatic antioxidant (glutathione - GSH) were quantified in three target organs - gill, kidney and liver. The lipid peroxidation (LPO) was also assessed as a marker of oxidative damage. GPx activity was decreased in gill (0.1 and 0.9 microM), whereas in the liver it was increased (0.3-2.7 microM). GST activity was decreased in kidney (0.3-2.7 microM) and CAT activity was increased in gill after 0.9 microM exposure. GSH content was significantly increased in gill by the lowest concentration and in liver by all Phe concentrations. Despite the antioxidant defense responses, LPO increased in gill (0.3-2.7 microM), kidney (0.1 microM) and liver (0.1 and 2.7 microM). These results revealed organ specific antioxidant defenses depending on the Phe concentration. Liver demonstrated a higher adaptive competence expressed as antioxidant defenses activation, namely GSH and GPX. The lower vulnerability of the kidney to oxidative damage (compared to gill and liver) seems to be related to its higher antioxidant basal levels. Globally, current data highlight the Phe potential to induce oxidative stress and, consequently, to affect the well-being of fish.

  16. Long-term power generation expansion planning with short-term demand response: Model, algorithms, implementation, and electricity policies

    NASA Astrophysics Data System (ADS)

    Lohmann, Timo

    Electric sector models are powerful tools that guide policy makers and stakeholders. Long-term power generation expansion planning models are a prominent example and determine a capacity expansion for an existing power system over a long planning horizon. With the changes in the power industry away from monopolies and regulation, the focus of these models has shifted to competing electric companies maximizing their profit in a deregulated electricity market. In recent years, consumers have started to participate in demand response programs, actively influencing electricity load and price in the power system. We introduce a model that features investment and retirement decisions over a long planning horizon of more than 20 years, as well as an hourly representation of day-ahead electricity markets in which sellers of electricity face buyers. This combination makes our model both unique and challenging to solve. Decomposition algorithms, and especially Benders decomposition, can exploit the model structure. We present a novel method that can be seen as an alternative to generalized Benders decomposition and relies on dynamic linear overestimation. We prove its finite convergence and present computational results, demonstrating its superiority over traditional approaches. In certain special cases of our model, all necessary solution values in the decomposition algorithms can be directly calculated and solving mathematical programming problems becomes entirely obsolete. This leads to highly efficient algorithms that drastically outperform their programming problem-based counterparts. Furthermore, we discuss the implementation of all tailored algorithms and the challenges from a modeling software developer's standpoint, providing an insider's look into the modeling language GAMS. Finally, we apply our model to the Texas power system and design two electricity policies motivated by the U.S. Environment Protection Agency's recently proposed CO2 emissions targets for the

  17. Short-term changes in the composition of active marine bacterial assemblages in response to diesel oil pollution.

    PubMed

    Lanfranconi, Mariana P; Bosch, Rafael; Nogales, Balbina

    2010-09-01

    The changes caused by diesel oil pollution in the metabolically active bacterioplankton from an oligotrophic coastal location were analysed in laboratory microcosms (44 l) using 16S ribosomal RNA (16S rRNA) as molecular marker. The aim was to simulate typical hydrocarbon pollution events in a coastal area exploited for seasonal touristic activities. The experiment consisted in addition of low amounts of diesel oil without nutrients to seawater collected at different times (winter and summer). Bacterial diversity was analysed by terminal-restriction fragment length polymorphism (T-RFLP) profiling of 16S rRNAs after reverse transcription polymerase chain reaction (RT-PCR), and by generation of 16S rRNA clone libraries in control and diesel-polluted microcosms. Diesel addition caused a twofold increase in prokaryotic numbers in comparison with controls at the end of the experiment, both in winter and summer microcosms. Bacterioplankton composition, determined by 16S rRNA T-RFLP data, changed rapidly (within 17 h) in response to treatment. The resulting communities were different in microcosms with water collected in summer and winter. A reduction in diversity (Shannon index, calculated on the basis of T-RFLP data) was observed only in summer microcosms. This was due to the rapid increase of phylotypes affiliated to the Oceanospirillaceae, not observed in winter microcosms. After diesel treatment there was a reduction in the number of phylotypes related to SAR11, SAR86 and picocyanobacteria, while phylotypes of the Roseobacter clade, and the OMG group seemed to be favoured. Our results show that diesel pollution alone caused profound effects on the bacterioplankton of oligotrophic seawater, and explained many of the differences in diversity reported previously in pristine and polluted sites in this coastal area.

  18. Generating short-term kinetic responses of primary metabolism of Penicillium chrysogenum through glucose perturbation in the bioscope mini reactor.

    PubMed

    Nasution, U; van Gulik, W M; Proell, A; van Winden, W A; Heijnen, J J

    2006-09-01

    A first study of the in vivo kinetic properties of primary metabolism of Penicillium chrysogenum is presented. Dynamic metabolite data have been generated by rapidly increasing the extracellular glucose concentration of cells cultivated under well-defined conditions in an aerobic glucose-limited chemostat followed by measurement of the fast dynamic response of the primary metabolite levels (glucose pulse experiment). These experiments were carried out directly in the chemostat as well as in a mini plug flow reactor (BioScope) outside the chemostat. The results of the glucose pulse experiments carried out in the chemostat and the Bioscope were highly similar. During the 90 s time window of the pulse experiment, the glucose consumption rate increased to a value twice as high as in the steady state, a much lower increase than observed for the fermenting yeast Saccharomyces cerevisiae under similar conditions. Although the observed metabolite patterns in P. chrysogenum were comparable to S. cerevisiae large differences in the magnitude of the dynamic behavior were observed between both organisms. During the pulse experiment the level of glycolytic and TCA cycle intermediates, and adenine nucleotides changed between two- and five-fold. Furthermore, a highly similar five-fold increase in the cytocolic NADH/NAD ratio could be calculated from two independent equilibrium assumptions (fructose 1,6 bis-phosphate to the pool of 2 and 3PG and oxaloacetate to fumarate with glutamate transaminase). It was also found that the C4 pool (aspartate, fumarate, and malate) became much more reduced due to this increase in NADH/NAD ratio. Equilibrium conditions were confirmed to exist in the hexose-P pool, the glycolysis between F16bP and 2+3PG and in the C4 pool of the TCA cycle (fumarate, malate, oxaloacetate and aspartate).

  19. Short-Term Unilateral Resistance Training Results in Cross Education of Strength Without Changes in Muscle Size, Activation, or Endocrine Response.

    PubMed

    Beyer, Kyle S; Fukuda, David H; Boone, Carleigh H; Wells, Adam J; Townsend, Jeremy R; Jajtner, Adam R; Gonzalez, Adam M; Fragala, Maren S; Hoffman, Jay R; Stout, Jeffrey R

    2016-05-01

    Short-term unilateral resistance training results in cross education of strength without changes in muscle size, activation, or endocrine response. J Strength Cond Res 30(5): 1213-1223, 2016-The purpose of this study was to assess the cross education of strength and changes in the underlying mechanisms (muscle size, activation, and hormonal response) after a 4-week unilateral resistance training (URT) program. A group of 9 untrained men completed a 4-week URT program on the dominant leg (DOM), whereas cross education was measured in the nondominant leg (NON); and were compared with a control group (n = 8, CON). Unilateral isometric force (PKF), leg press (LP) and leg extension (LE) strength, muscle size (by ultrasonography) and activation (by electromyography) of the rectus femoris and vastus lateralis, and the hormonal response (testosterone, growth hormone, insulin, and insulin-like growth factor-1) were tested pretraining and posttraining. Group × time interactions were present for PKF, LP, LE, and muscle size in DOM and for LP in NON. In all interactions, the URT group improved significantly better than CON. There was a significant acute hormonal response to URT, but no chronic adaptation after the 4-week training program. Four weeks of URT resulted in an increase in strength and size of the trained musculature, and cross education of strength in the untrained musculature, which may occur without detectable changes in muscle size, activation, or the acute hormonal response.

  20. Root spatial metabolite profiling of two genotypes of barley (Hordeum vulgare L.) reveals differences in response to short-term salt stress

    PubMed Central

    Shelden, Megan C.; Dias, Daniel A.; Jayasinghe, Nirupama S.; Bacic, Antony; Roessner, Ute

    2016-01-01

    Barley (Hordeum vulgare L.) is the most salt-tolerant cereal crop and has excellent genetic and genomic resources. It is therefore a good model to study salt-tolerance mechanisms in cereals. We aimed to determine metabolic differences between a cultivated barley, Clipper (tolerant), and a North African landrace, Sahara (susceptible), previously shown to have contrasting root growth phenotypes in response to the early phase of salinity stress. GC-MS was used to determine spatial changes in primary metabolites in barley roots in response to salt stress, by profiling three different regions of the root: root cap/cell division zone (R1), elongation zone (R2), and maturation zone (R3). We identified 76 known metabolites, including 29 amino acids and amines, 20 organic acids and fatty acids, and 19 sugars and sugar phosphates. The maintenance of cell division and root elongation in Clipper in response to short-term salt stress was associated with the synthesis and accumulation of amino acids (i.e. proline), sugars (maltose, sucrose, xylose), and organic acids (gluconate, shikimate), indicating a potential role for these metabolic pathways in salt tolerance and the maintenance of root elongation. The processes involved in root growth adaptation and the underlying coordination of metabolic pathways appear to be controlled in a region-specific manner. This study highlights the importance of utilizing spatial profiling and will provide us with a better understanding of abiotic stress response(s) in plants at the tissue and cellular level. PMID:26946124

  1. Industrial-age changes in atmospheric [CO2] and temperature differentially alter responses of faster- and slower-growing Eucalyptus seedlings to short-term drought.

    PubMed

    Lewis, James D; Smith, Renee A; Ghannoum, Oula; Logan, Barry A; Phillips, Nathan G; Tissue, David T

    2013-05-01

    Climate change may alter forest composition by differentially affecting the responses of faster- and slower-growing tree species to drought. However, the combined effects of rising atmospheric CO2 concentration ([CO2]) and temperature on drought responses of trees are poorly understood. Here, we examined interactive effects of temperature (ambient, ambient + °C) and [CO2] (290, 400 and 650mu;l l(-1)) on drought responses of Eucalyptus saligna Sm. (faster-growing) and E. sideroxylon A. Cunn. ex Woolls (slower-growing) seedlings. Drought was imposed via a controlled reduction in soil water over 1-2 weeks, re-watering seedlings when leaves visibly wilted. In ambient temperature, the effect of drought on the light-saturated net photosynthetic rate (Asat) in E. saligna decreased as [CO2] increased from pre-industrial to future concentrations, but rising [CO2] did not affect the response in Eucalyptus sideroxylon. In contrast, elevated temperature exacerbated the effect of drought in reducing Asat in both species. The drought response of Asat reflected changes in stomatal conductance (gs) associated with species and treatment differences in (i) utilization of soil moisture and (ii) leaf area ratio (leaf area per unit plant dry mass). Across [CO2] and temperature treatments, E. saligna wilted at higher soil water potentials compared with E. sideroxylon. Photosynthetic recovery from drought was 90% complete 2 days following re-watering across all species and treatments. Our results suggest that E. saligna (faster-growing) seedlings are more susceptible to drought than E. sideroxylon (slower-growing) seedlings. The greater susceptibility to drought of E. saligna reflected faster drawdown of soil moisture, associated with more leaf area and leaf area ratio, and the ability of E. sideroxylon to maintain higher gs at a given soil moisture. Inclusion of a pre-industrial [CO2] treatment allowed us to conclude that susceptibility of these species to short-term drought

  2. Short-term emergency response planning and risk assessment via an integrated modeling system for nuclear power plants in complex terrain

    NASA Astrophysics Data System (ADS)

    Chang, Ni-Bin; Weng, Yu-Chi

    2013-03-01

    Short-term predictions of potential impacts from accidental release of various radionuclides at nuclear power plants are acutely needed, especially after the Fukushima accident in Japan. An integrated modeling system that provides expert services to assess the consequences of accidental or intentional releases of radioactive materials to the atmosphere has received wide attention. These scenarios can be initiated either by accident due to human, software, or mechanical failures, or from intentional acts such as sabotage and radiological dispersal devices. Stringent action might be required just minutes after the occurrence of accidental or intentional release. To fulfill the basic functions of emergency preparedness and response systems, previous studies seldom consider the suitability of air pollutant dispersion models or the connectivity between source term, dispersion, and exposure assessment models in a holistic context for decision support. Therefore, the Gaussian plume and puff models, which are only suitable for illustrating neutral air pollutants in flat terrain conditional to limited meteorological situations, are frequently used to predict the impact from accidental release of industrial sources. In situations with complex terrain or special meteorological conditions, the proposing emergency response actions might be questionable and even intractable to decisionmakers responsible for maintaining public health and environmental quality. This study is a preliminary effort to integrate the source term, dispersion, and exposure assessment models into a Spatial Decision Support System (SDSS) to tackle the complex issues for short-term emergency response planning and risk assessment at nuclear power plants. Through a series model screening procedures, we found that the diagnostic (objective) wind field model with the aid of sufficient on-site meteorological monitoring data was the most applicable model to promptly address the trend of local wind field patterns

  3. Short-term heat shock affects the course of immune response in Galleria mellonella naturally infected with the entomopathogenic fungus Beauveria bassiana.

    PubMed

    Vertyporokh, Lidiia; Taszłow, Paulina; Samorek-Pieróg, Małgorzata; Wojda, Iwona

    2015-09-01

    We aimed to investigate how exposition of infected insects to short-term heat shock affects the biochemical and molecular aspects of their immune response. Galleria mellonella larvae were exposed to 43°C for 15min, at the seventy second hour after natural infection with entomopathogenic fungus Beauveria bassiana. As a result, both qualitative and quantitative changes in hemolymph protein profiles, and among them infection-induced changes in the amount of apolipophorin III (apoLp-III), were observed. Heat shock differently affects the expression of the tested immune-related genes. It transiently inhibits expression of antifungal peptides gallerimycin and galiomicin in both the fat body and hemocytes of infected larvae. The same, although to a lesser extent, concerned apoLp-III gene expression and was observed directly after heat shock. Nevertheless, in larvae that had recovered from heat shock, apoLp-III expression was higher in comparison to unshocked larvae in the fat body but not in hemocytes, which was consistent with the higher amount of this protein detected in the hemolymph of the infected, shocked larvae. Furthermore, lysozyme-type activity was higher directly after heat shock, while antifungal activity was significantly higher also in larvae that had recovered from heat shock, in comparison to the respective values in their non-shocked, infected counterparts. These results show how changes in the external temperature modulate the immune response of G. mellonella suffering from infection with its natural pathogen B. bassiana.

  4. Cytochrome P4501A, genotoxic and stress responses in golden grey mullet (Liza aurata) following short-term exposure to phenanthrene.

    PubMed

    Oliveira, M; Pacheco, M; Santos, M A

    2007-01-01

    This study represents a first approach to short-term effects of phenanthrene (Phe) in fish. The teleost Liza aurata was exposed to 0.1-2.7microM Phe during 16h. CYP1A induction was assessed as liver ethoxyresorufin-O-deethylase (EROD) activity. Genotoxicity was evaluated in gill and liver as DNA integrity (by alkaline unwinding), whereas in blood the erythrocytic nuclear abnormalities (ENA) frequency was determined. Stress responses were determined as cortisol, glucose and lactate plasma levels. Liver EROD activity was significantly increased by Phe 0.3-2.7microM. Phe genotoxicity in gill was not found, whereas liver DNA integrity significantly decreased after exposure to Phe 0.1 and 0.9microM demonstrating its genotoxicity which did not correlate with liver CYP1A induction. Phe genotoxicity in blood was demonstrated by a significant ENA increase from 0.1 up to 2.7microM. In terms of stress responses, plasma cortisol was significantly increased by Phe 0.3-2.7microM, though plasma glucose was only significantly increased by Phe 0.9 and 2.7microM. The Phe observed effects on L. aurata detected at different levels demonstrate a physiological unbalance and a probable ecological risk to ichthyofauna.

  5. Short-Term Response of Sasa Dwarf Bamboo to a Change of Soil Nitrogen Fertility in a Forest Ecosystem in Northern Hokkaido, Japan.

    PubMed

    Watanabe, Tsunehiro; Fukuzawa, Karibu; Shibata, Hideaki

    2016-04-14

    In forest ecosystems, a change of soil nitrogen (N) cycling after disturbance is regulated by various factors. Sasa dwarf bamboo (hereafter referred to as Sasa) is an understory plant that grows thickly on the forest floor in northern Hokkaido, Japan. However, the ecosystem function of Sasa after disturbances in the soil N cycling is not fully understood. The purpose of this study was to determine the short-term response of Sasa to a change of soil N fertility. Biomass, litterfall, litter decomposition, soil N pool, and N leaching from soil were measured in control, and low- (5 g N m(-2) year(-1)) and high-N (15 g N m(-2) year(-1)) addition plots. Sasa immobilized much N as the soil N fertility increased. However, the leaf N concentration in aboveground biomass did not increase, suggesting that the N in leaves was maintained because of the increase of leaf biomass. As a result, the decomposition and mineralization rates of the produced litter before and after N addition were comparable among plots, even though the soil inorganic N fertility increased greatly. These results suggest that immediate response of Sasa to an increase of soil inorganic N mitigates the excess N leaching from soil.

  6. Changes in hydraulic conductance cause the difference in growth response to short-term salt stress between salt-tolerant and -sensitive black gram (Vigna mungo) varieties.

    PubMed

    Win, Khin Thuzar; Oo, Aung Zaw; Ookawa, Taiichiro; Kanekatsu, Motoki; Hirasawa, Tadashii

    2016-04-01

    Black gram (Vigna mungo) is an important crop in Asia, However, most black gram varieties are salt-sensitive. The causes of varietal differences in salt-induced growth reduction between two black gram varieties, 'U-Taung-2' (salt-tolerant; BT) and 'Mut Pe Khaing To' (salt-sensitive; BS), were examined the potential for the first step toward the genetic improvement of salt tolerance. Seedlings grown in vermiculite irrigated with full-strength Hoagland solution were treated with 0mM NaCl (control) or 225 mM NaCl for up to 10 days. In the 225 mM NaCl treatment, plant growth rate, net assimilation rate, mean leaf area, leaf water potential, and leaf photosynthesis were reduced more in BS than in BT plants. Leaf water potential was closely related to leaf photosynthesis, net assimilation rate, and increase in leaf area. In response to salinity stress, hydraulic conductance of the root, stem, and petiole decreased more strongly in BS than in BT plants. The reduction in stem and petiole hydraulic conductance was caused by cavitation, whereas the reduction in root hydraulic conductance in BS plants was caused by a reduction in root surface area and hydraulic conductivity. We conclude that the different reduction in hydraulic conductance is a cause of the differences in the growth response between the two black gram varieties under short-term salt stress.

  7. Whole-body protein turnover response to short-term high-protein diets during weight loss: a randomized controlled trial.

    PubMed

    Pasiakos, S M; Margolis, L M; McClung, J P; Cao, J J; Whigham, L D; Combs, G F; Young, A J

    2014-07-01

    To determine whole-body protein turnover responses to high-protein diets during weight loss, 39 adults (age, 21±1 years; VO2peak, 48±1 ml kg(-1) min(-1); body mass index, 25±1 kg m(2)) were randomized to diets providing protein at the recommend dietary allowance (RDA), 2 × -RDA or 3 × -RDA. A 10-day weight maintenance period preceded a 21-day, 40% energy deficit. Postabsorptive (FASTED) and postprandial (FED) whole-body protein turnover was determined during weight maintenance (day 10) and energy deficit (day 31) using [1-(13)C]leucine. FASTED flux, synthesis and breakdown were lower (P<0.05) for energy deficit than weight maintenance. Protein flux and synthesis were higher (P<0.05) for FED than FASTED. Feeding attenuated (P<0.05) breakdown during weight maintenance but not energy deficit. Oxidation increased (P<0.05) between dietary protein levels and feeding stimulated oxidation, although oxidative responses to feeding were higher (P<0.05) for energy deficit than weight maintenance. FASTED net balance decreased between dietary protein levels, but in the FED state, net balance was lower for 3 × -RDA as compared with RDA and 2 × -RDA (diet-by-state, P<0.05). Consuming dietary protein at levels above the RDA, particularly 3 × -RDA, during short-term weight loss increases protein oxidation with concomitant reductions in net protein balance.

  8. Use of the Integrated Biomarker Response to Measure the Effect of Short-term Exposure to Dibenz[a,h]anthracene in Common carp (Cyprinus carpio).

    PubMed

    Kim, Ja-Hyun; Kim, Woo-Keun

    2016-04-01

    Dibenz[a,h]anthracene (DbA) is a polycyclic aromatic hydrocarbon that is released into the environment through incomplete combustion of gasoline, cigarettes, and coal tar. The effects of short-term (10 days) exposure of common carp (Cyprinus carpio) to DbA (0-50 µg L(-1)) were evaluated using the following four biomarkers: DNA damage, 7-ethoxyresorufin-O-deethylase (EROD) activity, acetylcholinesterase (AChE) activity, and vitellogenin (VTG) levels. An integrated biomarker response (IBR) was calculated for exposure to DbA, and the results were compared with those in our previous study of two other PAHs, benzo[k]fluoranthene (BkF) and benzo[a]pyrene (BaP). DbA exposure resulted in a significant (p < 0.05) increase in DNA damage, EROD activity, and VTG levels relative to the control. By contrast, DbA did not affect AChE activity. The IBR increased as the concentration of DbA increased. Based on the IBR values, the order of toxicity for the PAHs was BkF > BaP > DbA. Our results suggest that the IBR can be used as a quantitative tool for evaluating the responses of multiple biomarkers to PAH exposure.

  9. Short-term response to a booster dose of hepatitis B vaccine in anti-HBs negative adolescents who had received primary vaccination 16 years ago.

    PubMed

    Wang, Li-Yu; Lin, Hans Hsienhong

    2007-10-10

    We conducted a revaccination study to investigate the short-term response to booster hepatitis B (HB) vaccination in seronegative adolescents who had received primary infantile HB vaccination. A booster dose of recombinant HB vaccine was administered to 395 adolescents 15-18 years of age whose serum titers of antibody against hepatitis B surface antigen (HBsAg) (anti-HBs) were <10 mIU/mL. Seventy-seven percent of the booster recipients converted to anti-HBs seropositivity (postbooster titers> or =10 mIU/mL). As compared with adolescents who had undetectable prebooster anti-HBs titers (<0.1 mIU/mL), the seropositive rates and geometric mean titers (GMTs) of 2-month and 1-year postbooster were significantly higher for those of prebooster titers of 0.1-0.9 and 1.0-9.9 mIU/mL (all p<0.0001). Postbooster titers declined significantly more rapidly for those with undetectable prebooster anti-HBs titers than for those with prebooster titers of 0.1-0.9 and 1.0-9.9 mIU/mL. Our observations indicate that a booster dose of HB vaccine maybe unable to induce sufficient immunological response in adolescents who had undetectable residual anti-HBs titers.

  10. Short-Term Response of Sasa Dwarf Bamboo to a Change of Soil Nitrogen Fertility in a Forest Ecosystem in Northern Hokkaido, Japan

    PubMed Central

    Watanabe, Tsunehiro; Fukuzawa, Karibu; Shibata, Hideaki

    2016-01-01

    In forest ecosystems, a change of soil nitrogen (N) cycling after disturbance is regulated by various factors. Sasa dwarf bamboo (hereafter referred to as Sasa) is an understory plant that grows thickly on the forest floor in northern Hokkaido, Japan. However, the ecosystem function of Sasa after disturbances in the soil N cycling is not fully understood. The purpose of this study was to determine the short-term response of Sasa to a change of soil N fertility. Biomass, litterfall, litter decomposition, soil N pool, and N leaching from soil were measured in control, and low- (5 g N m−2 year−1) and high-N (15 g N m−2 year−1) addition plots. Sasa immobilized much N as the soil N fertility increased. However, the leaf N concentration in aboveground biomass did not increase, suggesting that the N in leaves was maintained because of the increase of leaf biomass. As a result, the decomposition and mineralization rates of the produced litter before and after N addition were comparable among plots, even though the soil inorganic N fertility increased greatly. These results suggest that immediate response of Sasa to an increase of soil inorganic N mitigates the excess N leaching from soil. PMID:27135238

  11. Tree ring isotopes of beech and spruce in response to short-term climate variability across Central European sites: Common and contrasting physiological mechanisms

    NASA Astrophysics Data System (ADS)

    Weigt, Rosemarie; Klesse, Stefan; Treydte, Kerstin; Frank, David; Saurer, Matthias; Siegwolf, Rolf T. W.

    2016-04-01

    The combined study of tree-ring width and stable C and O isotopes provides insight in the coherences between carbon allocation during stem growth and the preceding conditions of gas exchange and formation of photosynthates as all influenced by environmental variation. In this large-scale study comprising 10 sites across a range of climate gradients (temperature, precipitation) throughout Central Europe, we investigated tree-rings in European beech (Fagus sylvatica) and Norway spruce (Picea abies) trees. The sampling design included larger and smaller trees. The short-term, i.e. year-to-year, variability in the isotope time series over 100 yrs was analyzed in relation to tree-ring growth and climate variation. The generally strong correlation between the year-to-year differences in δ13C (corrected for the atmospheric shift due to 13C-depleted CO2 from fossil combustion) and δ18O across most sites emphasized the role of stomatal conductance in controlling leaf gas exchange. However, the correlation between both isotopes decreased during some periods. At several sites this reduction in correlation was particularly pronounced during recent decades. This suggests a decoupling between stomatal and photosynthetic responses to environmental conditions on the one hand, and carbon allocation to stem tissue on the other hand. Variability in the isotopic ratio largely responded to summer climate, but was weakly correlated to annual stem growth. In contrast, climate sensitivity of radial growth in both species was rather site-dependent, and was strongest at the driest (in terms of soil water capacity) site. We will also present results of isotope responses with respect to extreme climate events. Understanding the underlying physiological mechanisms controlling the short-term variation in tree-ring signals will help to assess and more precisely constrain the possible range of growth performance of these ecologically and economically important tree species under future climate

  12. Repeatability of baseline corticosterone and short-term corticosterone stress responses, and their correlation with testosterone and body condition in a terrestrial breeding anuran (Platymantis vitiana).

    PubMed

    Narayan, Edward J; Cockrem, John F; Hero, Jean-Marc

    2013-06-01

    Repeatability of physiological response variables, such as the stress hormone corticosterone, across numerous sampling occasions is an important assumption for their use as predictors of behaviour, reproduction and fitness in animals. Very few studies have actually tested this assumption in free-living animals under uncontrolled natural conditions. Non-invasive urine sampling and standard capture handling protocol have enabled the rapid quantification of baseline corticosterone and short-term corticosterone stress responses in anuran amphibians. In this study, established non-invasive methods were used to monitor physiological stress and urinary testosterone levels in male individuals of the terrestrial breeding Fijian ground frog (Platymantis vitiana). Adult male frogs (n = 20) were sampled at nighttime on three repeated occasions at intervals of 14 days during their annual breeding season on Viwa Island, Fiji. All frogs expressed urinary corticosterone metabolite responses to the capture and handling stressor, with some frogs showing consistently higher urinary corticosterone responses than others. Ranks of corticosterone values at 0, 4 and 8 h, and the corrected rank were highly significant (r = 0.75-0.99) between the three repeated sampling occasions. Statistical repeatabilities were high for baseline corticosterone (r = 0.973) and for corticosterone values at 2 h (r = 0.862), 4 h (r = 0.861), 6 h (r = 0.820) and 8 h (r = 0.926), and also for the total (inclusive of baseline corticosterone values) and the corrected integrated responses (index of the acute response) [r = 0.867 and r = 0.870]. Urinary testosterone levels also showed high statistical repeatability (r = 0.78). Furthermore, variation in baseline and short-term corticosterone stress responses was greater between individuals than within individuals. Baseline urinary corticosterone was significantly negatively correlated with the corrected integrated corticosterone response (r = -0.3, p < 0.001) but

  13. Theoretical models of synaptic short term plasticity

    PubMed Central

    Hennig, Matthias H.

    2013-01-01

    Short term plasticity is a highly abundant form of rapid, activity-dependent modulation of synaptic efficacy. A shared set of mechanisms can cause both depression and enhancement of the postsynaptic response at different synapses, with important consequences for information processing. Mathematical models have been extensively used to study the mechanisms and roles of short term plasticity. This review provides an overview of existing models and their biological basis, and of their main properties. Special attention will be given to slow processes such as calcium channel inactivation and the effect of activation of presynaptic autoreceptors. PMID:23626536

  14. Low residual proliferation after short-term letrozole therapy is an early predictive marker of response in high proliferative ER-positive breast cancer.

    PubMed

    Bedard, Philippe L; Singhal, Sandeep K; Ignatiadis, Michail; Bradbury, Ian; Haibe-Kains, Benjamin; Desmedt, Christine; Loi, Sherene; Evans, Dean B; Michiels, Stefan; Dixon, J Michael; Miller, William R; Piccart, Martine J; Sotiriou, Christos

    2011-12-01

    The gene expression grade index (GGI) is a 97-gene algorithm that measures proliferation and divides intermediate histological grade tumors into two distinct groups. We investigated the association between early changes in GGI and clinical response to neoadjuvant letrozole and compared this to Ki67 values. The paired gene expression data at the beginning and after 10-14 days of neoadjuvant letrozole treatment were available for 52 post-menopausal patients with estrogen receptor (ER)-positive breast cancer. Baseline values and changes in GGI, Ki67, and RNA expression modules representing oncogenic signaling pathways were compared to sonographic tumor volume changes after 3 months of treatment in the subsets of patients defined by high and low baseline GGI. The clinical response was observed in 80% genomic low-grade (24/30) and 59% genomic high-grade (13/22) tumors (P=0.10). Low residual proliferation after 10-14 days of neoadjuvant letrozole therapy, measured by either GGI or Ki67, was associated with sonographic response in genomic high-grade (GGI, P=0.003; Ki67, P=0.017) but not genomic low-grade (GGI, P=0.25; Ki67, P=1.0) tumors. The analysis of expression modules suggested that sonographic response to letrozole in genomic high-grade tumors was associated with an early reduction in IGF1 signaling (unadjusted P=0.018). The major conclusion of this study is that the early assessment of proliferation after short-term endocrine therapy may be useful to evaluate endocrine responsiveness, particularly in genomic high-grade ER-positive breast cancer.

  15. Short-term inhibition of TERT induces telomere length-independent cell cycle arrest and apoptotic response in EBV-immortalized and transformed B cells

    PubMed Central

    Celeghin, Andrea; Giunco, Silvia; Freguja, Riccardo; Zangrossi, Manuela; Nalio, Silvia; Dolcetti, Riccardo; De Rossi, Anita

    2016-01-01

    Besides its canonical role in stabilizing telomeres, telomerase reverse transcriptase (TERT) may promote tumorigenesis through extra-telomeric functions. The possible therapeutic effects of BIBR1532 (BIBR), a powerful TERT inhibitor, have been evaluated in different cellular backgrounds, but no data are currently available regarding Epstein–Barr virus (EBV)-driven B-cell malignancies. Our aim was to characterize the biological effects of TERT inhibition by BIBR on EBV-immortalized lymphoblastoid cell lines (LCLs) and fully transformed Burkitt's lymphoma (BL) cell lines. We found that BIBR selectively inhibits telomerase activity in TERT-positive 4134/Late and 4134/TERT+ LCLs and EBV-negative BL41 and EBV-positive BL41/B95.8 BL cell lines. TERT inhibition led to decreased cell proliferation, accumulation of cells in the S-phase and ultimately to increased apoptosis, compared with mock-treated control cells. All these effects occurred within 72 h and were not observed in BIBR-treated TERT-negative 4134/TERT- and U2OS cells. The cell cycle arrest and apoptosis, consequent upon short-term TERT inhibition, were associated with and likely dependent on the activation of the DNA damage response (DDR), highlighted by the increased levels of γH2AX and activation of ATM and ATR pathways. Analyses of the mean and range of telomere lengths and telomere dysfunction-induced foci indicated that DDR after short-term TERT inhibition was not related to telomere dysfunction, thus suggesting that TERT, besides stabilizing telomere, may protect DNA via telomere-independent mechanisms. Notably, TERT-positive LCLs treated with BIBR in combination with fludarabine or cyclophosphamide showed a significant increase in the number of apoptotic cells with respect to those treated with chemotherapeutic agents alone. In conclusion, TERT inhibition impairs cell cycle progression and enhances the pro-apoptotic effects of chemotherapeutic agents in TERT-positive cells. These results support new

  16. Measuring the short-term substrate utilization response to high-carbohydrate and high-fat meals in the whole-body indirect calorimeter.

    PubMed

    Gribok, Andrei; Leger, Jayme L; Stevens, Michelle; Hoyt, Reed; Buller, Mark; Rumpler, William

    2016-06-01

    The paper demonstrates that minute-to-minute metabolic response to meals with different macronutrient content can be measured and discerned in the whole-body indirect calorimeter. The ability to discriminate between high-carbohydrate and high-fat meals is achieved by applying a modified regularization technique with additional constraints imposed on oxygen consumption rate. These additional constraints reduce the differences in accuracy between the oxygen and carbon dioxide analyzers. The modified technique was applied to 63 calorimeter sessions that were each 24 h long. The data were collected from 16 healthy volunteers (eight males, eight females, aged 22-35 years). Each volunteer performed four 24-h long calorimeter sessions. At each session, they received one of four treatment combinations involving exercise (high or low intensity) and diet (a high-fat or high-carbohydrate shake for lunch). One volunteer did not complete all four assignments, which brought the total number of sessions to 63 instead of 64. During the 24-h stay in the calorimeter, subjects wore a continuous glucose monitoring system, which was used as a benchmark for subject's postprandial glycemic response. The minute-by-minute respiratory exchange ratio (RER) data showed excellent agreement with concurrent subcutaneous glucose concentrations in postprandial state. The averaged minute-to-minute RER response to the high-carbohydrate shake was significantly different from the response to high-fat shake. Also, postprandial RER slopes were significantly different for two dietary treatments. The results show that whole-body respiration calorimeters can be utilized as tools to study short-term kinetics of substrate oxidation in humans.

  17. Male poplars have a stronger ability to balance growth and carbohydrate accumulation than do females in response to a short-term potassium deficiency.

    PubMed

    Yang, Yanni; Jiang, Hao; Wang, Maolin; Korpelainen, Helena; Li, Chunyang

    2015-12-01

    Potassium (K) deficiency influences plant performance, such as ion uptake and carbohydrate transport. However, little is known about differences between males and females in response to K deficiency. In this study, dry matter accumulation, photosynthetic capacity, allocation patterns of K(+) , Na(+) and carbohydrates, and ultrastructural changes in males and females of Populus cathayana exposed to K deficiency were investigated. The results indicated that males maintained a significantly higher K(+) content and K(+) /Na(+) ratio in leaves and stems than did females under K deficiency. Moreover, K deficiency significantly increased the sucrose content of females, whereas no significant effect on males was detected. In addition, a comparative analysis showed that males allocated more resources to roots, while females allocated more to leaves, which resulted in sexually different root/shoot (R/S) ratios. Transmission electron microscopic (TEM) observations showed that males suffered fewer injuries than did females. These results suggested that males have a better ability to cope with K deficiency. In addition, the combined effects of salinity and K deficiency on poplars were studied. The results indicated that salt stress aggravates the negative effects caused by K deficiency. Taken together, our study provided evidence for gender-specific strategies in ion and carbohydrate allocation in poplars exposed to a short-term K deficiency. In leaves and stems, the lower K(+) accumulation inhibited sucrose translocation and resulted in a decreased R/S ratio, which may contribute to males having a stronger ability to balance growth and carbohydrate accumulation when compared with females.

  18. Using a suppression subtractive library-based approach to identify tobacco genes regulated in response to short-term sulphur deficit.

    PubMed

    Wawrzyńska, Anna; Lewandowska, Małgorzata; Hawkesford, Malcolm J; Sirko, Agnieszka

    2005-06-01

    Monitoring expression at the transcriptional level is an essential first step for the functional analysis of plant genes. Genes encoding proteins directly involved in sulphur metabolism constitute only a small fraction of all the genes affected by sulphur deficiency stress. Transcriptional responses to various periods of sulphur deprivation have been extensively studied in Arabidopsis thaliana; however, no corresponding data are available for Solanaceae sp. To address this problem, a subtractive library-based approach to search for tobacco genes regulated by a short-term sulphur starvation has been adopted. In this work, 38 genes were identified, of which 22 were regulated positively and 16 were regulated negatively. The transcript levels of the representative genes were monitored in four parts of the plants (mature and immature leaves, stems, and roots), which exhibited differential sulphur deficiency. Interestingly, some genes exhibit different regulation of expression in different parts of the plants. Database analysis allowed assignment of the potential function for many of the identified genes; however, the functions of a small number of genes strongly regulated by sulphur starvation remain unknown. The genes were grouped into nine functional categories, each including both up- and down-regulated genes. The possible links between the identified regulated genes and sulphur metabolism are considered, and compared where possible with expression patterns in Arabidopsis thaliana. Although no obvious regulatory genes were identified, the genes encoding proteins of unknown function remain as potential components of the regulatory processes.

  19. Rapid response of arbuscular mycorrhizal fungal communities to short-term fertilization in an alpine grassland on the Qinghai-Tibet Plateau

    PubMed Central

    Xiang, Xingjia; Gibbons, Sean M.; He, Jin-Sheng; Wang, Chao; He, Dan; Li, Qian; Ni, Yingying

    2016-01-01

    Background: The Qinghai-Tibet Plateau (QTP) is home to the vast grassland in China. The QTP grassland ecosystem has been seriously degraded by human land use practices and climate change. Fertilization is used in this region to increase vegetation yields for grazers. The impact of long-term fertilization on plant and microbial communities has been studied extensively. However, the influence of short-term fertilization on arbuscular mycorrhizal fungal (AMF) communities in the QTP is largely unknown, despite their important functional role in grassland ecosystems. Methods: We investigated AMF community responses to three years of N and/or P addition at an experimental field site on the QTP, using the Illumina MiSeq platform (PE 300). Results: Fertilization resulted in a dramatic shift in AMF community composition and NP addition significantly increased AMF species richness and phylogenetic diversity. Aboveground biomass, available phosphorus, and NO3− were significantly correlated with changes in AMF community structure. Changes in these factors were driven by fertilization treatments. Thus, fertilization had a large impact on AMF communities, mediated by changes in aboveground productivity and soil chemistry. Discussion: Prior work has shown how plants often lower their reliance on AMF symbioses following fertilization, leading to decrease AMF abundance and diversity. However, our study reports a rise in AMF diversity with fertilization treatment. Because AMF can provide stress tolerance to their hosts, we suggest that extreme weather on the QTP may help drive a positive relationship between fertilizer amendment and AMF diversity. PMID:27478711

  20. Induction of a Specific Strong Polyantigenic Cellular Immune Response after Short-Term Chemotherapy Controls Bacillary Reactivation in Murine and Guinea Pig Experimental Models of Tuberculosis▿

    PubMed Central

    Guirado, Evelyn; Gil, Olga; Cáceres, Neus; Singh, Mahavir; Vilaplana, Cristina; Cardona, Pere-Joan

    2008-01-01

    RUTI is a therapeutic vaccine that is generated from detoxified and liposomed Mycobacterium tuberculosis cell fragments that has demonstrated its efficacy in the control of bacillus reactivation after short-term chemotherapy. The aim of this study was to characterize the cellular immune response generated after the therapeutic administration of RUTI and to corroborate the lack of toxicity of the vaccine. Mouse and guinea pig experimental models were infected with a low-dose M. tuberculosis aerosol. RUTI-treated animals showed the lowest bacillary load in both experimental models. RUTI also decreased the percentage of pulmonary granulomatous infiltration in the mouse and guinea pig models. This was not the case after Mycobacterium bovis BCG treatment. Cellular immunity was studied through the characterization of the intracellular gamma interferon (IFN-γ)-producing cells after the splenocytes' stimulation with M. tuberculosis-specific structural and growth-related antigens. Our data show that the difference between the therapeutic administration of BCG and RUTI resides mainly in the stronger activation of IFN-γ+ CD4+ cells and CD8+ cells against tuberculin purified protein derivative, ESAT-6, and Ag85B that RUTI generates. Both vaccines also triggered a specific immune response against the M. tuberculosis structural antigens Ag16kDa and Ag38kDa and a marked mRNA expression of IFN-γ, tumor necrosis factor, interleukin-12, inducible nitric oxide synthase, and RANTES in the lung. The results show that RUTI's therapeutic effect is linked not only to the induction of a Th1 response but also to the stimulation of a quicker and stronger specific immunity against structural and growth-related antigens that reduces both the bacillary load and the pulmonary pathology. PMID:18524883

  1. Short-term dietary concentrate supplementation during estrus synchronization treatment in beef cows increased IGF-I serum concentration but did not affect the reproductive response.

    PubMed

    Rosales-Torres, A M; López-Cedillo, Z B; Hernández-Coronado, C G; Rosete-Fernández, J V; Mendoza, G D; Guzmán, A

    2017-01-01

    The objective of this study was to evaluate if short-term dietary concentrate supplementation increased IGF-I serum concentration and resulted in a reproductive response during estrus synchronization treatment in non-lactating beef cows. Thirty non-lactating beef cows (Bos indicus × Bos taurus) were allocated to the same pastureland and fed native tropical grasses as a basal diet. Cows were synchronized using a 7-day CO-Synch plus controlled internal drug release (CIDR) protocol and received fixed time artificial insemination (FTAI). Cows were divided into two groups; the control group (n = 16) received 0.5 kg of concentrate/cow/day, whereas the supplemented group (n = 14) received 4.0 kg of concentrate/cow/day. The period of supplementation was 10 days from the day of CIDR insert to FTAI. The concentration of IGF-I increased (P < 0.05) in the supplemented group, while no significant changes were observed in the control group. Moreover, at the time of insemination, IGF-I serum concentrations were higher in supplemented cows compared with control cows (P < 0.05). Notably, metabolite and insulin concentrations did not differ (P > 0.05) between treatment groups or sampling day. The response to estrus induction, measured as estrus presentation, ovulation rate, and pregnancy rate, was similar between experimental groups (P > 0.05). In conclusion, our results indicated that supplementation with dietary concentrate for 10 days in non-lactating beef cows changed the endocrine milieu, specifically increasing IGF-I serum concentration. However, these endocrine changes did not affect response to estrous induction treatment.

  2. Short-term energy outlook

    SciTech Connect

    Not Available

    1990-11-07

    The Energy Information Administration (EIA) presents future scenarios of quarterly short-term energy supply, demand, and prices for publication in February, May, August, and November in the Short-Term Energy Outlook (Outlook). An annual supplement analyzes previous estimate errors, compares recent scenarios with those of other forecasting services, and discusses current topics of the short-term energy markets. (See Short-Term Energy Outlook: Annual Supplement, DOE/EIA-0202.) The principal users of the Outlook are managers and energy analysts in private industry and government. The scenario period for this issue of the Outlook extends from the fourth quarter of 1990 through the fourth quarter of 1991. Some data for the third quarter of 1990 are preliminary EIA estimates of actual data (for example, some petroleum estimates are based on statistics from the Weekly Petroleum Status Report) or are derived from internal model simulations using the latest exogenous information available (for example, some electricity demand estimates are based on recent weather data). 11 figs., 13 tabs.

  3. Acute sodium ingestion has no effect on short-term food and water intake, subjective appetite, thirst, or glycemic response in healthy young men.

    PubMed

    Nunez, Maria Fernanda; Mollard, Rebecca C; Luhovyy, Bohdan L; Wong, Christina L; Anderson, G Harvey

    2013-07-01

    The high intake of dietary sodium (Na(+)) has been associated with obesity and insulin resistance, sparking the hypothesis that the consumption of salty foods affects food intake (FI) and postprandial blood glucose (BG) response. Therefore, we conducted 2 randomized repeated-measures experiments to examine the acute effects of the Na(+) content of solid food and beverage on FI, water intake (WI), subjective appetite, thirst, and BG. FI and WI were measured at ad libitum pizza test meals; appetite, thirst, and BG were measured at baseline and at regular intervals before and after meals. In the first experiment, 16 males (mean body mass index (BMI), 22.2 kg·m(-2)) consumed a low-Na(+) (71 mg) bean preload (300 kcal) with or without 740 mg or 1480 mg of added Na(+) 120 min prior to the pizza meal. Participants ate 116 kcal more at the test meal after consuming beans with 740 mg of added Na(+) than after beans with 1480 mg of added Na(+). In the second experiment, 19 males (mean BMI, 23.2 kg·m(-2)) consumed a low-Na(+) (62 mg) tomato beverage (73 kcal) with or without 500, 1000, 1500, or 2000 mg of added Na(+) 30 min prior to a pizza meal. The beverage with 2000 mg of added Na(+) led to higher WI during the pizza meal than the beverage with 500 mg of added Na(+). However, compared with the control conditions (no added Na(+)), added Na(+) treatments had no effect on dependent measures in either experiment. In conclusion, the acute intake of Na(+), in a solid or liquid form, did not affect short-term subjective ratings of appetite or thirst, ad libitum FI or WI, or BG in healthy young men.

  4. Short-term population-based and spatiotemporal nonlinear concentration-response associations between fine particulate matter and children's respiratory clinic visits

    NASA Astrophysics Data System (ADS)

    Yu, Hwa-Lung; Chien, Lung-Chang

    2014-05-01

    Advert health impacts associated with the PM2.5 exposure have been confirmed in mortality and cardiovascular diseases; however, findings of the influence of PM2.5 on respiratory diseases investigated among previous studies are still inconsistent. We investigated the short-term population-based associations between the respiratory clinic visits of children population and the PM2.5 exposure levels with considering both the spatiotemporal distributions of the ambient pollution and clinic visit data. We applied a spatiotemporal structured additive regression model to examine the concentration-response (C-R) association between daily children's respiratory clinic visits and PM2.5 concentrations. The analysis was performed separately on the four selected respiratory disease categories of the population-based dataset, obtained from Taiwan National Health Insurance database, covering the 41 districts in Taipei area during the period of 2005 to 2007. This study reveals a strong nonlinear C-R pattern that the PM2.5 increment can significantly affect respiratory health at PM2.5 concentration ≤ 18.17µg/m3 for both preschool children and schoolchildren. The elevated risks are especially present in the category of acute respiratory infections. PM2.5 increase is mostly non-significant to the more severe respiratory diseases, e.g., COPD and pneumonia, over the ranges of 8.85-92.45µg/m3. The significantly higher relative rate of respiratory clinic visit most likely concentrated at populated areas. We highlight the nonlinearity of the respiratory health impacts of PM2.5 on children's populations from the first study, to our knowledge, to investigate this population-based association. The strong nonlinearity can possibly cause the inconsistency of PM2.5 health impact assessments with linear assumptions.

  5. Reproductive response of fat-tailed Barbarine ewes subjected to short-term nutritional treatments including spineless cactus (Opuntia ficus-indica f. inermis) cladodes.

    PubMed

    Sakly, C; Rekik, M; Ben Salem, I; Lassoued, N; Gonzalez-Bulnes, A; Ben Salem, H

    2014-02-01

    Reproductive outputs in fat-tailed Barbarine sheep in central Tunisia are often low because of feed shortage and the low nutritive value of diets. Supplementation with conventional concentrates is economically unsuitable in central Tunisia, so more cost-effective and sustainable alternative feeding strategies need to be developed. We tested effects of short-term nutritional treatments including cactus cladodes during the induction of 'male effect' on fertility and prolificacy parameters (follicular growth, ovulatory response and early embryo losses). One hundred and twenty ewes were distributed in 4 equal groups balanced for live weight grazed natural pastures and were supplemented for 21 days, starting day 10 after introduction of rams, with cactus cladodes (CA), cactus cladodes and soybean meal (CAS), concentrate (CC) or only soybean meal (S). Nutritional treatment did not affect live weight in this experiment. Ewes receiving cactus had higher number of large pre-ovulatory follicles (≥6 mm; 1.08 ± 0.05), between days 14 and 19 after introduction of rams, than females in the CC and S ewes (0.64 ± 0.06; p < 0.05). However, there were no differences in the onset of oestrous behaviour in response to 'male effect' or in the number of corpora lutea. Average ovulation rates were 1.42 ± 0.16 for CC, 1.47 ± 0.13 for CAS, 1.31 ± 0.15 for CA and 1.31 ± 0.13 for S groups respectively. Finally, reproductive wastages at day 35 after mating were not different between groups being 0.33 ± 0.19 for CC, 0.60 ± 0.17 for CAS, 0.43 ± 0.16 for CA and 0.31 ± 0.15 for S groups respectively. It is concluded that Barbarine ewes fed nutritional treatments including cactus performed similarly to those receiving diets including conventional concentrate feeds.

  6. Short-term population-based non-linear concentration-response associations between fine particulate matter and respiratory diseases in Taipei (Taiwan): a spatiotemporal analysis.

    PubMed

    Yu, Hwa-Lung; Chien, Lung-Chang

    2016-01-01

    Fine particulate matter <2.5 μm (PM2.5) has been associated with human health issues; however, findings regarding the influence of PM2.5 on respiratory disease remain inconsistent. The short-term, population-based association between the respiratory clinic visits of children and PM2.5 exposure levels were investigated by considering both the spatiotemporal distributions of ambient pollution and clinic visit data. We applied a spatiotemporal structured additive regression model to examine the concentration-response (C-R) association between children's respiratory clinic visits and PM2.5 concentrations. This analysis was separately performed on three respiratory disease categories that were selected from the Taiwanese National Health Insurance database, which includes 41 districts in the Taipei area of Taiwan from 2005 to 2007. The findings reveal a non-linear C-R pattern of PM2.5, particularly in acute respiratory infections. However, a PM2.5 increase at relatively lower levels can elevate the same-day respiratory health risks of both preschool children (<6 years old) and schoolchildren (6-14 years old). In preschool children, same-day health risks rise when concentrations increase from 0.76 to 7.44 μg/m(3), and in schoolchildren, same-day health risks rise when concentrations increase from 0.76 to 7.52 μg/m(3). Changes in PM2.5 levels generally exhibited no significant association with same-day respiratory risks, except in instances where PM2.5 levels are extremely high, and these occurrences do exhibit a significant positive influence on respiratory health that is especially notable in schoolchildren. A significant high relative rate of respiratory clinic visits are concentrated in highly populated areas. We highlight the non-linearity of the respiratory health effects of PM2.5 on children to investigate this population-based association. The C-R relationship in this study can provide a highly valuable alternative for assessing the effects of ambient air

  7. Short-term response in milk production, dry matter intake, and grazing behavior of dairy cows to changes in postgrazing sward height.

    PubMed

    Ganche, E; Delaby, L; O'Donovan, M; Boland, T M; Kennedy, E

    2014-05-01

    Postgrazing sward height (PGSH) can be altered to adjust the allowance of grass in the dairy cow's diet. This study aimed to investigate the short-term dairy cow response to a change in postgrazing height in early lactation. Ninety Holstein Friesian spring-calving cows were randomly assigned across 3 postgrazing height treatments (n=30): 2.7 cm (severe), 3.5 cm (low), and 4.2 cm (moderate) from February 14 to April 24, 2011. From April 25, animals were rerandomized within each treatment to graze across 2 postgrazing heights: 3.5 cm (low) or 4.5 cm (high). Animal production measurements were taken from April 4 to 24 (measurement period 1; M1) and from April 25 to May 15 (measurement period 2; M2). The 6 treatments (n=15) of M2 were severe-low, severe-high, low-low, low-high, moderate-low, and moderate-high. During M1, increasing postgrazing height from severe to low to moderate linearly increased daily milk yield (21.5, 24.6 and 25.8 kg/cow per day) and grass dry matter intake (GDMI; 13.2, 14.9, and 15.8 kg of DM/cow per day). Milk solids yield was reduced in the severe (-1,518 g/cow per day) treatment when compared with the low and moderate cows (1,866 g/cow per day, on average). The milk yield (MY) response to change in PGSH between M1 and M2 (VM1-M2) was established using VM1-M2 MY=-1.27-1.89 × PGSHM1 + 1.51 × PGSHM2 (R(2)=0.64). The MY response associated with each treatment between M1 and M2 (3 wk) were -1.03 kg/cow for severe-low, 0.68 kg/cow for severe-high, -2.56 kg/cow for low-low, -1.11 kg/cow for low-high, -4.17 kg/cow for moderate-low, and -2.39 kg/cow for moderate-high. The large increase in energy intake in severe-high between M1 and M2 was achieved through higher GDMI per minute and GDMI per bite, which supported the positive change in MY. Treatments low-high, moderate-low, and moderate-high recorded the highest overall cumulative milk yield (74 kg of milk solids/cow) over the 6-wk period, whereas severe-low and severe-high had the lowest (65 kg of

  8. Electricity generation and microbial community in response to short-term changes in stack connection of self-stacked submersible microbial fuel cell powered by glycerol.

    PubMed

    Zhao, Nannan; Angelidaki, Irini; Zhang, Yifeng

    2017-02-01

    Stack connection (i.e., in series or parallel) of microbial fuel cell (MFC) is an efficient way to boost the power output for practical application. However, there is little information available on short-term changes in stack connection and its effect on the electricity generation and microbial community. In this study, a self-stacked submersible microbial fuel cell (SSMFC) powered by glycerol was tested to elucidate this important issue. In series connection, the maximum voltage output reached to 1.15 V, while maximum current density was 5.73 mA in parallel. In both connections, the maximum power density increased with the initial glycerol concentration. However, the glycerol degradation was even faster in parallel connection. When the SSMFC was shifted from series to parallel connection, the reactor reached to a stable power output without any lag phase. Meanwhile, the anodic microbial community compositions were nearly stable. Comparatively, after changing parallel to series connection, there was a lag period for the system to get stable again and the microbial community compositions became greatly different. This study is the first attempt to elucidate the influence of short-term changes in connection on the performance of MFC stack, and could provide insight to the practical utilization of MFC.

  9. Linking gene expression to productivity to unravel long- and short-term responses of seagrasses exposed to CO2 in volcanic vents

    PubMed Central

    Olivé, Irene; Silva, João; Lauritano, Chiara; Costa, Monya M.; Ruocco, Miriam; Procaccini, Gabriele; Santos, Rui

    2017-01-01

    Ocean acidification is a major threat for marine life but seagrasses are expected to benefit from high CO2. In situ (long-term) and transplanted (short-term) plant incubations of the seagrass Cymodocea nodosa were performed near and away the influence of volcanic CO2 vents at Vulcano Island to test the hypothesis of beneficial effects of CO2 on plant productivity. We relate, for the first time, the expression of photosynthetic, antioxidant and metal detoxification-related genes to net plant productivity (NPP). Results revealed a consistent pattern between gene expression and productivity indicating water origin as the main source of variability. However, the hypothesised beneficial effect of high CO2 around vents was not supported. We observed a consistent long- and short-term pattern of gene down-regulation and 2.5-fold NPP decrease in plants incubated in water from the vents and a generalized up-regulation and NPP increase in plants from the vent site incubated with water from the Reference site. Contrastingly, NPP of specimens experimentally exposed to a CO2 range significantly correlated with CO2 availability. The down-regulation of metal-related genes in C. nodosa leaves exposed to water from the venting site suggests that other factors than heavy metals, may be at play at Vulcano confounding the CO2 effects. PMID:28205566

  10. Linking gene expression to productivity to unravel long- and short-term responses of seagrasses exposed to CO2 in volcanic vents

    NASA Astrophysics Data System (ADS)

    Olivé, Irene; Silva, João; Lauritano, Chiara; Costa, Monya M.; Ruocco, Miriam; Procaccini, Gabriele; Santos, Rui

    2017-02-01

    Ocean acidification is a major threat for marine life but seagrasses are expected to benefit from high CO2. In situ (long-term) and transplanted (short-term) plant incubations of the seagrass Cymodocea nodosa were performed near and away the influence of volcanic CO2 vents at Vulcano Island to test the hypothesis of beneficial effects of CO2 on plant productivity. We relate, for the first time, the expression of photosynthetic, antioxidant and metal detoxification-related genes to net plant productivity (NPP). Results revealed a consistent pattern between gene expression and productivity indicating water origin as the main source of variability. However, the hypothesised beneficial effect of high CO2 around vents was not supported. We observed a consistent long- and short-term pattern of gene down-regulation and 2.5-fold NPP decrease in plants incubated in water from the vents and a generalized up-regulation and NPP increase in plants from the vent site incubated with water from the Reference site. Contrastingly, NPP of specimens experimentally exposed to a CO2 range significantly correlated with CO2 availability. The down-regulation of metal-related genes in C. nodosa leaves exposed to water from the venting site suggests that other factors than heavy metals, may be at play at Vulcano confounding the CO2 effects.

  11. Effect of short-term exercise-heat acclimation on ventilatory and cerebral blood flow responses to passive heating at rest in humans.

    PubMed

    Fujii, Naoto; Tsuji, Bun; Honda, Yasushi; Kondo, Narihiko; Nishiyasu, Takeshi

    2015-09-01

    Hyperthermia induces hyperventilation and cerebral hypoperfusion in resting humans. We tested the hypothesis that short-term exercise-heat acclimation would alleviate those effects. Twenty healthy male subjects were divided into two groups that performed exercise training in the heat (TR-HEAT, n = 10) or cold (TR-COLD, n = 10). Before and after the training, the subjects in both groups participated in passive-heat tests at rest. Training was performed at 37°C (TR-HEAT) or 10°C (TR-COLD) and entailed four 20-min bouts of cycling at 50% peak oxygen uptake separated by 10-min recoveries daily for 6 consecutive days. After TR-HEAT, esophageal temperature was lowered when measured before and during passive heating, as was the esophageal temperature threshold for cutaneous active vasodilation, whereas plasma volume was increased (all P < 0.05). These traditional indices of successful heat acclimation were not all induced by TR-COLD (all P > 0.05). TR-HEAT had no significant effect on passive heating-induced increases in minute ventilation, even when evaluated as the esophageal temperature threshold for increases in minute ventilation and the slope relating minute ventilation to esophageal temperature (all P > 0.05). By contrast, TR-HEAT attenuated the passive heating-induced reduction in the cerebral vascular conductance index (middle cerebral artery mean blood velocity/mean arterial pressure) (all P < 0.05). TR-COLD did not attenuate the increase in minute ventilation or the decrease in the cerebral vascular conductance index observed during passive heating (all P > 0.05). These data suggest that in resting heated humans, short-term heat acclimation achieved through moderate-intensity exercise training (i.e., 50% peak oxygen uptake) in the heat does not influence hyperthermia-induced hyperventilation, but it does potentially attenuate cerebral hypoperfusion.

  12. Differential responses of short-term soil respiration dynamics to the experimental addition of nitrogen and water in the temperate semi-arid steppe of Inner Mongolia, China.

    PubMed

    Qi, Yuchun; Liu, Xinchao; Dong, Yunshe; Peng, Qin; He, Yating; Sun, Liangjie; Jia, Junqiang; Cao, Congcong

    2014-04-01

    We examined the effects of simulated rainfall and increasing N supply of different levels on CO2 pulse emission from typical Inner Mongolian steppe soil using the static opaque chamber technique, respectively in a dry June and a rainy August. The treatments included NH4NO3 additions at rates of 0, 5, 10, and 20 g N/(m(2)·year) with or without water. Immediately after the experimental simulated rainfall events, the CO2 effluxes in the watering plots without N addition (WCK) increased greatly and reached the maximum value at 2 hr. However, the efflux level reverted to the background level within 48 hr. The cumulative CO2 effluxes in the soil rang ed from 5.60 to 6.49 g C/m(2) over 48 hr after a single water application, thus showing an increase of approximately 148.64% and 48.36% in the effluxes during both observation periods. By contrast, the addition of different N levels without water addition did not result in a significant change in soil respiration in the short term. Two-way ANOVA showed that the effects of the interaction between water and N addition were insignificant in short-term soil CO2 effluxes in the soil. The cumulative soil CO2 fluxes of different treatments over 48 hr accounted for approximately 5.34% to 6.91% and 2.36% to 2.93% of annual C emission in both experimental periods. These results stress the need for improving the sampling frequency after rainfall in future studies to ensure more accurate evaluation of the grassland C emission contribution.

  13. Onboard Short Term Plan Viewer

    NASA Technical Reports Server (NTRS)

    Hall, Tim; LeBlanc, Troy; Ulman, Brian; McDonald, Aaron; Gramm, Paul; Chang, Li-Min; Keerthi, Suman; Kivlovitz, Dov; Hadlock, Jason

    2011-01-01

    Onboard Short Term Plan Viewer (OSTPV) is a computer program for electronic display of mission plans and timelines, both aboard the International Space Station (ISS) and in ISS ground control stations located in several countries. OSTPV was specifically designed both (1) for use within the limited ISS computing environment and (2) to be compatible with computers used in ground control stations. OSTPV supplants a prior system in which, aboard the ISS, timelines were printed on paper and incorporated into files that also contained other paper documents. Hence, the introduction of OSTPV has both reduced the consumption of resources and saved time in updating plans and timelines. OSTPV accepts, as input, the mission timeline output of a legacy, print-oriented, UNIX-based program called "Consolidated Planning System" and converts the timeline information for display in an interactive, dynamic, Windows Web-based graphical user interface that is used by both the ISS crew and ground control teams in real time. OSTPV enables the ISS crew to electronically indicate execution of timeline steps, launch electronic procedures, and efficiently report to ground control teams on the statuses of ISS activities, all by use of laptop computers aboard the ISS.

  14. Response to Dr Stevens' letter ref. Visitisen et al: "Short-term effects of night shift work on breast cancer risk: a cohort study of payroll data".

    PubMed

    Kolstad, Henrik A; Garde, Anne Helene; Hansen, Åse Marie; Frydenberg, Morten; Christiansen, Peer; Vistisen, Helene Tilma; Bonde, Jens Peter E

    2017-01-01

    selection bias, but we observed similar risk estimates as for the total study population. Taken together, we find that our study provides rather robust evidence of no short-term breast cancer risk following recent night shift work. It must, however, be stressed that data did not allow assessment of a possible long-term risk. Reference 1. Stevens R. Letter ref. Vitisen et al: "Short-term effects of night shift work on breast cancer risk: a cohort study of payroll data". Scand J Work Environ Health. 2017;43(1):95. http://dx.doi.org/10.5271/sjweh.3607 2. Vistisen HT, Garde AH, Frydenberg M, Christiansen P, Hansen AM, Hansen J, Bonde JP, Kolstad HA. Short-term effects of night shift work on breast cancer risk: A cohort study of payroll data. Scand J Work Environ Health. 2017;43(1):59-67. http://dx.doi.org/10.5271/sjweh.3603. 3. Ijaz S, Verbeek J, Seidler A, Lindbohm ML, Ojajarvi A, Orsini N, Costa G, Neuvonen K. Night-shift work and breast cancer--a systematic review and meta-analysis. Scand J Work Environ Health. 2013 Sep 1;39(5):431-47. http://dx.doi.org/10.5271/sjweh.3371.

  15. Late Holocene dune mobilizations in the northwestern Negev dunefield, Israel: A response to combined anthropogenic activity and short-term intensified windiness

    NASA Astrophysics Data System (ADS)

    Roskin, Joel; Katra, Itzhak; Blumberg, Dan G.

    2013-04-01

    The study of the effects of past climates on ancient cultures is usually based on geologic records pertaining to rainfall and temperature fluctuations and shifts. This study proposes a paradigm of anthropogenic activity and windiness fluctuations to explain aeolian sedimentation and dune mobilization in the northwestern (NW) Negev Desert dunefield (Israel). The proposed paradigm contributes a different approach to estimating the effect of climate changes on the unprecedented agricultural and urban settlement expansion during the late Roman to Early Islamic period in the northern and central Negev Desert. This study builds upon the late Holocene cluster of luminescence ages of Roskin et al. (Age, origin and climatic controls on vegetated linear dunes in the northwestern Negev Desert (Israel), Quaternary Science Reviews 30 (2011), 1649-1674) coupled with analysis of archaeological finds and historical texts. We suggest that whereas the NW Negev dunefield was generally stable during the Holocene, intermittent dune mobilization during the late Holocene, at ~1.8 ka and mostly 1.4-1.1 ka (~600-900 CE), are linked to periods of human occupation. The idea that the last glacial dune encroachments alone that formed the NW Negev dunefield is connected to cold-event windy climates that may have intensified East Mediterranean cyclonic winter storms, cannot explain the late Holocene dune mobilizations. We conceptually model a connection between late Holocene dune mobilization, widespread anthropogenic occupation and activity, and windiness. We maintain that historic grazing and uprooting shrubs for fuel in the past by nomads and sedentary populations led to decimation of dune stabilizers, biogenic soil crusts and vegetation, causing dune erodibility and low-grade activity. Short-term events of amplified wind power in conjunction with periods of augmented anthropogenic activity that triggered major events of dune mobilization (elongation) and accretion have been preserved in the

  16. Short-term or long-term treatments with a phosphodiesterase-4 (PDE4) inhibitor result in opposing agonist-induced Ca2+ responses in endothelial cells

    PubMed Central

    Campos-Toimil, M; Keravis, T; Orallo, F; Takeda, K; Lugnier, C

    2008-01-01

    Background and purpose: We previously reported that agonist-induced rises in cytoplasmic Ca2+ concentration ([Ca2+]i) in human umbilical vein endothelial cells (HUVEC) were inhibited after a short-term (2 min) pre-treatment with cAMP-elevating agents. The aim of this work was to study the effects of longer term (8 h) pre-treatment with dibutyryl-cAMP (db-cAMP) or rolipram, a specific inhibitor of phosphodiesterase-4 (PDE4), on [Ca2+]i, cAMP levels and PDE activity and expression in HUVEC. Experimental approach: [Ca2+]i changes were measured in isolated HUVEC by Fura-2 imaging. Intracellular cAMP levels and PDE4 activity were assessed by enzyme-immunoassay and radio-enzymatic assay, respectively. PDE expression was measured by northern and western blot analysis. Key results: Long-term pre-treatment of HUVEC with rolipram or db-cAMP significantly increased ATP-, histamine- and thrombin-induced [Ca2+]i rises. Short-term pre-treatment with rolipram was associated with an increase in cAMP, whereas long-term pre-treatment was associated with a decrease in cAMP. Long-term pre-treatment with rolipram or db-cAMP induced a significant increase in PDE4 activity and the expression of 74 kDa-PDE4A and 73 kDa-PDE4B was specifically enhanced. All these effects were suppressed by cycloheximide. Conclusions and implications: Our data suggest that sustained inhibition of PDE4 by rolipram induced an increase in PDE4 activity, possibly as a compensatory mechanism to accelerate cAMP degradation and that PDE4A and PDE4B were implicated in the regulation of [Ca2+]i. Thus, isozyme-specific PDE4 inhibitors might be useful as therapeutic agents in diseases where [Ca2+]i handling is altered, such as atherosclerosis, hypertension and tolerance to β-adrenoceptor agonists. PMID:18311187

  17. [Response of reactive oxygen metabolism in melon chloroplasts to short-term salinity-alkalinity stress regulated by exogenous γ-aminobutyric acid].

    PubMed

    Xiang, Li-xia; Hu, Li-pan; Hu, Xiao-hui; Pan, Xiong-bo; Ren, Wen-qi

    2015-12-01

    The regulatory effect of exogenous γ-aminobutyric acid (GABA) on metabolism of reactive oxygen species (ROS) in melon chloroplasts under short-term salinity-alkalinity stress were investigated in melon variety 'Jinhui No. 1', which was cultured with deep flow hydroponics. The result showed that under salinity-alkalinity stress, the photosynthetic pigment content, MDA content, superoxide anion (O₂·) production rate and hydrogen peroxide (H₂O₂) content in chloroplast increased significantly, the contents of antioxidants ascorbic acid (AsA) and glutathione (GSH) increased, and the activities of H⁺-ATPase and H⁺-PPiase were inhibited obviously. With exogenous GABA application, the accumulations of O₂·, MDA and H₂O₂ induced by salinity-alkalinity stress were inhibited. Exogenous GABA alleviated the increase of photosynthetic pigment content, improved the activity of SOD, enzymes of AsA-GSH cycle, total AsA and total GSH while decreased the AsA/DHA ratio and GSH/GSSH ratio. Foliar GABA could enhance the H⁺-ATPase and H⁺-PPiase activities. Our results suggested that the exogenous GABA could accelerate the ROS metabolism in chloroplast, promote the recycle of AsA-GSH, and maintain the permeability of cell membrane to improve the ability of melon chloroplast against salinity-alkalinity stress.

  18. Surface coal mine land reclamation using a dry flue gas desulfurization product: Short-term and long-term water responses.

    PubMed

    Chen, Liming; Stehouwer, Richard; Tong, Xiaogang; Kost, Dave; Bigham, Jerry M; Dick, Warren A

    2015-09-01

    Abandoned coal-mined lands are a worldwide concern due to their potential negative environmental impacts, including erosion and development of acid mine drainage. A field study investigated the use of a dry flue gas desulfurization product for reclamation of abandoned coal mined land in USA. Treatments included flue gas desulfurization product at a rate of 280 Mg ha(-1) (FGD), FGD at the same rate plus 112 Mg ha(-1) yard waste compost (FGD/C), and conventional reclamation that included 20 cm of re-soil material plus 157 Mg ha(-1) of agricultural limestone (SOIL). A grass-legume sward was planted after treatment applications. Chemical properties of surface runoff and tile water (collected from a depth of 1.2m below the ground surface) were measured over both short-term (1-4 yr) and long-term (14-20 yr) periods following reclamation. The pH of surface runoff water was increased from approximately 3, and then sustained at 7 or higher by all treatments for up to 20 yr, and the pH of tile flow water was also increased and sustained above 5 for 20 yr. Compared with SOIL, concentrations of Ca, S and B in surface runoff and tile flow water were generally increased by the treatments with FGD product in both short- and long-term measurements and concentrations of the trace elements were generally not statistically increased in surface runoff and tile flow water over the 20-yr period. However, concentrations of As, Ba, Cr and Hg were occasionally elevated. These results suggest the use of FGD product for remediating acidic surface coal mined sites can provide effective, long-term reclamation.

  19. European eel (Anguilla anguilla) genotoxic and pro-oxidant responses following short-term exposure to Roundup--a glyphosate-based herbicide.

    PubMed

    Guilherme, S; Gaivão, I; Santos, M A; Pacheco, M

    2010-09-01

    The glyphosate-based herbicide, Roundup, is among the most used pesticides worldwide. Due to its extensive use, it has been widely detected in aquatic ecosystems representing a potential threat to non-target organisms, including fish. Despite the negative impact of this commercial formulation in fish, as described in literature, the scarcity of studies assessing its genotoxicity and underlying mechanisms is evident. Therefore, as a novel approach, this study evaluated the genotoxic potential of Roundup to blood cells of the European eel (Anguilla anguilla) following short-term (1 and 3 days) exposure to environmentally realistic concentrations (58 and 116 microg/l), addressing also the possible association with oxidative stress. Thus, comet and erythrocytic nuclear abnormalities (ENAs) assays were adopted, as genotoxic end points, reflecting different types of genetic damage. The pro-oxidant state was assessed through enzymatic (catalase, glutathione-S-transferase, glutathione peroxidase and glutathione reductase) and non-enzymatic (total glutathione content) antioxidants, as well as by lipid peroxidation (LPO) measurements. The Roundup potential to induce DNA strand breaks for both concentrations was demonstrated by the comet assay. The induction of chromosome breakage and/or segregational abnormalities was also demonstrated through the ENA assay, though only after 3-day exposure to both tested concentrations. In addition, the two genotoxic indicators were positively correlated. Antioxidant defences were unresponsive to Roundup. LPO levels increased only for the high concentration after the first day of exposure, indicating that oxidative stress caused by this agrochemical in blood was not severe. Overall results suggested that both DNA damaging effects induced by Roundup are not directly related with an increased pro-oxidant state. Moreover, it was demonstrated that environmentally relevant concentrations of Roundup can pose a health risk for fish populations.

  20. Hydrological responses in water loss due to thinning of forested watersheds in Japan using the short-term water balance method

    NASA Astrophysics Data System (ADS)

    Sano, K.; Gomi, T.; Hiraoka, M.; Sato, T.; Onda, Y.

    2015-12-01

    We examined the changes in seasonal patterns of catchment-scale evapotranspiration (i.e., water loss) using Short-Term Water Balance Model (STWBM) developed. STWBM is applied to estimate the value of water loss based on precipitation minus discharge volume during short-periods(8 to 80 days). This method can be applicable for examining seasonal characteristics of water loss that relets to ET. We applied STWBM for investigating the effects of 50% thinning in nested headwater catchments draining Japanese cypress (Cryptomeria japonica) and cedar (Chamaecyparis obtusa) forests. Study areas is located to 70 km north of Tokyo with 1250 mm annual precipitation and 14℃ mean annual temperature. 50% of the stems (46% of timber volume) were removed by strip thinning in 17 ha treatment catchment, 9 ha catchment remained untreated as a control. We installed 4 nested gauging stations in treated and control catchments with 3 to 10 ha of drainage areas. Runoff in each nested gauging station was measured in the pre- (from April, 2010 to June 2011) and the post-thinning periods (from January 2012 to December 2012). Total runoff coefficient in treated and control catchment was 54% and 26%, respectively. , . Estimated annual water loss by STWBM was 585 mm in treated and 969 mm in control catchments. Because annual evapotranspiration of Japanese cypress and cedar was about ranging from 400 to 800 mm in this catchment, our estimated water loss mostly associated with ET and partially by water loss by deep bedrock percolation. Estimated water loss after thinning in growth season (May to October) decreased 45 to 60 (in 2012) % and 51 to 60 (in 2013) % for all nested gauging station, while estimated water loss in control catchment was consistent. This result suggested that 50% of thinning decreased water loss by ET but changes can be varied among nested gauging station.

  1. Short-term effect of a high-protein/low-carbohydrate diet on aminopeptidase in adult rat jejunoileum. Site of aminopeptidase response.

    PubMed

    Raul, F; Goda, T; Gossé, F; Koldovský, O

    1987-10-15

    The short-term effects of high-protein/low-carbohydrate diet on aminopeptidase N activity were studied in the brush-border membranes of proximal jejunum and proximal ileum of adult rats. The animals were starved overnight and re-fed for 15 h either with a standard diet (20% protein, 55% carbohydrate, in terms of energy content) or with a high-protein/low-carbohydrate diet of equal energy content (70% protein, 5% carbohydrate). All rats consumed similar amounts of diet, and measurements were made 15 h after initiation of re-feeding. In the proximal jejunum a slight increase in aminopeptidase activity was observed after the high-protein intake. In contrast, considerable stimulation (52%) of the enzyme specific activity was obtained in the proximal ileum. This increase in ileal aminopeptidase activity was more prominent in the mature cells of the upper villus. To determine if the increase of aminopeptidase activity was due to an increased amount of enzyme protein, rocket immunoelectrophoresis was performed with detergent-solubilized brush-border protein from ileum on agarose gels containing anti-(rat brush-border) antiserum. When the same amount of enzyme activity was loaded on the gels, the peaks of immunoprecipitate for aminopeptidase were similar for animals fed on a standard or a high-protein diet. When the same amount of protein was loaded, the peak of immunoprecipitate for aminopeptidase was higher (81%) after a high-protein diet. These results showed that the high protein intake evoked an increase in aminopeptidase activity, with a concomitant increase in the amount of immunoreactive protein.

  2. Physiological and productive responses of multiparous lactating Holstein cows exposed to short-term cooling during severe summer conditions in an arid region of Mexico

    NASA Astrophysics Data System (ADS)

    Avendaño-Reyes, L.; Hernández-Rivera, J. A.; Álvarez-Valenzuela, F. D.; Macías-Cruz, U.; Díaz-Molina, R.; Correa-Calderón, A.; Robinson, P. H.; Fadel, J. G.

    2012-11-01

    Heat stress generates a significant economic impact for the dairy industry in arid and semi-arid regions of the world, so that heat abatement is an important issue for dairy producers. The objective of this study was to evaluate effects of two short-term cooling periods on physiological and productive status of lactating Holstein cows during hot ambient temperatures. Thirty-nine multiparous cows were blocked by milk yield and assigned to one of three treatments including: control group (C), cows cooled before milking time (0500 and 1700 h daily, 1 h cooling); AM group, cows cooled at 1000 h and before milking (2 h cooling); and AM + PM group, cows cooled at 1100, 1500 and 2200 h, as well as before milking (4 h cooling). The cooling system was placed in the holding pen which the cows were moved through for cooling. Respiratory rate, and temperatures of thurl and right flank, were lower ( P < 0.05) in cows from the AM + PM group than AM and C cows during the morning and afternoon. However, udder temperature was higher in the AM + PM group compared to AM and C groups during the afternoon, although lower than the AM group during the morning. Rectal temperature was similar in all groups. Thyroxin concentrations tended ( P < 0.10) to be lower in AM + PM relative to the AM and C groups. The AM + PM group had higher ( P < 0.05) milk production than C (18.70 vs. 17.43 kg, respectively), and AM + PM cows had a trend ( P < 0.10) to increased milk energy output vs. the C and AM groups (13.75 vs. 13.18 and 13.15 Mcal, respectively). Protein and fat in milk, body condition score, glucose, cholesterol, triglycerides and triiodothyronine were similar among the groups. Four hours of cooling with spray and fans during severe summer temperatures only modestly improved milk yield of lactating Holstein cows.

  3. One-Time Addition of Nano-TiO2 Triggers Short-Term Responses in Benthic Bacterial Communities in Artificial Streams.

    PubMed

    Ozaki, Alexandra; Adams, Erin; Binh, Chu Thi Thanh; Tong, Tiezheng; Gaillard, Jean-François; Gray, Kimberly A; Kelly, John J

    2016-02-01

    Nano-TiO2 is an engineered nanomaterial whose production and use are increasing rapidly. Hence, aquatic habitats are at risk for nano-TiO2 contamination due to potential inputs from urban and suburban runoff and domestic wastewater. Nano-TiO2 has been shown to be toxic to a wide range of aquatic organisms, but little is known about the effects of nano-TiO2 on benthic microbial communities. This study used artificial stream mesocosms to assess the effects of a single addition of nano-TiO2 (P25 at a final concentration of 1 mg l(-1)) on the abundance, activity, and community composition of sediment-associated bacterial communities. The addition of nano-TiO2 resulted in a rapid (within 1 day) decrease in bacterial abundance in artificial stream sediments, but bacterial abundance returned to control levels within 3 weeks. Pyrosequencing of partial 16S rRNA genes did not indicate any significant changes in the relative abundance of any bacterial taxa with nano-TiO2 treatment, indicating that nano-TiO2 was toxic to a broad range of bacterial taxa and that recovery of the bacterial communities was not driven by changes in community composition. Addition of nano-TiO2 also resulted in short-term increases in respiration rates and denitrification enzyme activity, with both returning to control levels within 3 weeks. The results of this study demonstrate that single-pulse additions of nano-TiO2 to aquatic habitats have the potential to significantly affect the abundance and activity of benthic microbial communities and suggest that interactions of TiO2 nanoparticles with environmental matrices may limit the duration of their toxicity.

  4. Use of the short-term inflammatory response in the mouse peritoneal cavity to assess the biological activity of leached vitreous fibers.

    PubMed Central

    Donaldson, K; Addison, J; Miller, B G; Cullen, R T; Davis, J M

    1994-01-01

    We used a special-purpose glass microfiber sample, Johns-Manville Code 100/475, to study the effects of various acid and alkali treatments on biological activity as assessed by inflammation in the mouse peritoneal cavity, the leaching of Si, and the phase contrast optical microscopy (PCOM) fiber number. We used mild and medium treatments with oxalic acid and Tris buffer and harsh treatment with concentrated HCl and NaOH. Mild oxalic acid and Tris treatment for 2 weeks had no effect on any of the end-points, but prolonging the mild oxalic acid treatment time to 2 months reduced the biological activity and the fiber number. Medium oxalic acid treatment reduced the biological activity and the fiber number and caused a loss of Si. Medium Tris alkali treatment reduced the PCOM-countable fibers and the biological activity but did not cause a substantial loss of Si. Harsh treatment with strong HCl did not affect the fiber number or cause leaching but the biological activity was reduced; strong NaOH reduced the fiber number and biological activity, and caused marked leaching of Si. The medium oxalic acid conditions (pH 1.4) were more acid than those found in lung cells but produced the same effects (reduction in fiber number and biological activity) as the more physiological mild treatment (pH 4.0), when prolonged. This study suggests that medium oxalic acid treatment can be used as a short-term assay to compare loss of Si, reduction in fiber number, and change in biological activity of vitreous fibers.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7882922

  5. Evaluation of the fate and pathological response in the lung and pleura of brake dust alone and in combination with added chrysotile compared to crocidolite asbestos following short-term inhalation exposure.

    PubMed

    Bernstein, D M; Rogers, R A; Sepulveda, R; Kunzendorf, P; Bellmann, B; Ernst, H; Creutzenberg, O; Phillips, J I

    2015-02-15

    This study was designed to provide an understanding of the biokinetics and potential toxicology in the lung and pleura following inhalation of brake dust following short term exposure in rats. The deposition, translocation and pathological response of brake-dust derived from brake pads manufactured with chrysotile were evaluated in comparison to the amphibole, crocidolite asbestos. Rats were exposed by inhalation 6h/day for 5 days to either brake-dust obtained by sanding of brake-drums manufactured with chrysotile, a mixture of chrysotile and the brake-dust or crocidolite asbestos. The chrysotile fibers were relatively biosoluble whereas the crocidolite asbestos fibers persisted through the life-time of the animal. This was reflected in the lung and the pleura where no significant pathological response was observed at any time point in the brake dust or chrysotile/brake dust exposure groups through 365 days post exposure. In contrast, crocidolite asbestos produced a rapid inflammatory response in the lung parenchyma and the pleura, inducing a significant increase in fibrotic response in both of these compartments. Crocidolite fibers were observed embedded in the diaphragm with activated mesothelial cells immediately after cessation of exposure. While no chrysotile fibers were found in the mediastinal lymph nodes, crocidolite fibers of up to 35 μm were observed. These results provide support that brake-dust derived from chrysotile containing brake drums would not initiate a pathological response in the lung or the pleural cavity following short term inhalation.

  6. Physiological and productive responses of multiparous lactating Holstein cows exposed to short-term cooling during severe summer conditions in an arid region of Mexico.

    PubMed

    Avendaño-Reyes, L; Hernández-Rivera, J A; Alvarez-Valenzuela, F D; Macías-Cruz, U; Díaz-Molina, R; Correa-Calderón, A; Robinson, P H; Fadel, J G

    2012-11-01

    Heat stress generates a significant economic impact for the dairy industry in arid and semi-arid regions of the world, so that heat abatement is an important issue for dairy producers. The objective of this study was to evaluate effects of two short-term cooling periods on physiological and productive status of lactating Holstein cows during hot ambient temperatures. Thirty-nine multiparous cows were blocked by milk yield and assigned to one of three treatments including: control group (C), cows cooled before milking time (0500 and 1700 h daily, 1 h cooling); AM group, cows cooled at 1000 h and before milking (2 h cooling); and AM + PM group, cows cooled at 1100, 1500 and 2200 h, as well as before milking (4 h cooling). The cooling system was placed in the holding pen which the cows were moved through for cooling. Respiratory rate, and temperatures of thurl and right flank, were lower (P < 0.05) in cows from the AM + PM group than AM and C cows during the morning and afternoon. However, udder temperature was higher in the AM + PM group compared to AM and C groups during the afternoon, although lower than the AM group during the morning. Rectal temperature was similar in all groups. Thyroxin concentrations tended (P < 0.10) to be lower in AM + PM relative to the AM and C groups. The AM + PM group had higher (P < 0.05) milk production than C (18.70 vs. 17.43 kg, respectively), and AM + PM cows had a trend (P < 0.10) to increased milk energy output vs. the C and AM groups (13.75 vs. 13.18 and 13.15 Mcal, respectively). Protein and fat in milk, body condition score, glucose, cholesterol, triglycerides and triiodothyronine were similar among the groups. Four hours of cooling with spray and fans during severe summer temperatures only modestly improved milk yield of lactating Holstein cows.

  7. Two emerging concepts for elite athletes: the short-term effects of testosterone and cortisol on the neuromuscular system and the dose-response training role of these endogenous hormones.

    PubMed

    Crewther, Blair T; Cook, Christian; Cardinale, Marco; Weatherby, Robert P; Lowe, Tim

    2011-02-01

    The aim of this review is to highlight two emerging concepts for the elite athlete using the resistance-training model: (i) the short-term effects of testosterone (T) and cortisol (C) on the neuromuscular system; and (ii) the dose-response training role of these endogenous hormones. Exogenous evidence confirms that T and C can regulate long-term changes in muscle growth and performance, especially with resistance training. This evidence also confirms that changes in T or C concentrations can moderate or support neuromuscular performance through various short-term mechanisms (e.g. second messengers, lipid/protein pathways, neuronal activity, behaviour, cognition, motor-system function, muscle properties and energy metabolism). The possibility of dual T and C effects on the neuromuscular system offers a new paradigm for understanding resistance-training performance and adaptations. Endogenous evidence supports the short-term T and C effects on human performance. Several factors (e.g. workout design, nutrition, genetics, training status and type) can acutely modify T and/or C concentrations and thereby potentially influence resistance-training performance and the adaptive outcomes. This novel short-term pathway appears to be more prominent in athletes (vs non-athletes), possibly due to the training of the neuromuscular and endocrine systems. However, the exact contribution of these endogenous hormones to the training process is still unclear. Research also confirms a dose-response training role for basal changes in endogenous T and C, again, especially for elite athletes. Although full proof within the physiological range is lacking, this athlete model reconciles a proposed permissive role for endogenous hormones in untrained individuals. It is also clear that the steroid receptors (cell bound) mediate target tissue effects by adapting to exercise and training, but the response patterns of the membrane-bound receptors remain highly speculative. This information

  8. Evaluation of the fate and pathological response in the lung and pleura of brake dust alone and in combination with added chrysotile compared to crocidolite asbestos following short-term inhalation exposure

    SciTech Connect

    Bernstein, D.M.; Rogers, R.A.; Sepulveda, R.; Kunzendorf, P.; Bellmann, B.; Ernst, H.; Creutzenberg, O.; Phillips, J.I.

    2015-02-15

    This study was designed to provide an understanding of the biokinetics and potential toxicology in the lung and pleura following inhalation of brake dust following short term exposure in rats. The deposition, translocation and pathological response of brake-dust derived from brake pads manufactured with chrysotile were evaluated in comparison to the amphibole, crocidolite asbestos. Rats were exposed by inhalation 6 h/day for 5 days to either brake-dust obtained by sanding of brake-drums manufactured with chrysotile, a mixture of chrysotile and the brake-dust or crocidolite asbestos. The chrysotile fibers were relatively biosoluble whereas the crocidolite asbestos fibers persisted through the life-time of the animal. This was reflected in the lung and the pleura where no significant pathological response was observed at any time point in the brake dust or chrysotile/brake dust exposure groups through 365 days post exposure. In contrast, crocidolite asbestos produced a rapid inflammatory response in the lung parenchyma and the pleura, inducing a significant increase in fibrotic response in both of these compartments. Crocidolite fibers were observed embedded in the diaphragm with activated mesothelial cells immediately after cessation of exposure. While no chrysotile fibers were found in the mediastinal lymph nodes, crocidolite fibers of up to 35 μm were observed. These results provide support that brake-dust derived from chrysotile containing brake drums would not initiate a pathological response in the lung or the pleural cavity following short term inhalation. - Highlights: • Evaluated brake dust w/wo added chrysotile in comparison to crocidolite asbestos. • Persistence, translocation, pathological response in the lung and pleural cavity. • Chrysotile cleared rapidly from the lung while the crocidolite asbestos persisted. • No significant pathology in lung or pleural cavity observed at any time point in the brake-dust groups. • Crocidolite quickly

  9. Coupled stratospheric ozone and temperature responses to short-term changes in solar ultraviolet flux - An analysis of Nimbus 7 SBUV and SAMS data. [stratosphere and mesosphere sounder

    NASA Technical Reports Server (NTRS)

    Hood, L. L.

    1986-01-01

    Earlier studies of solar-induced variations in stratospheric parameters have been mainly concerned with observed ozone responses. In the present investigation, attention is given to temperature responses as well as ozone responses at low latitudes, taking into account 22 months of Nimbus 7 solar backscattered ultraviolet (SBUV) ozone and stratospheric and mesospheric sounder temperature data. A data description is provided, and cross-correlation and regression analyses are conducted. An extension is considered of an analytic model, which was derived by Frederick (1981) for the coupled behavior of ozone and temperature perturbations in the upper stratosphere and lower mesosphere. The extended model is applied to the results of the analyses. The obtained data provide statistical evidence for ozone and temperature responses to changes in solar ultraviolet flux on the time scale of the solar rotation period.

  10. Short-Term Responses in Maximum Quantum Yield of PSII (Fv/Fm) to ex situ Temperature Treatment of Populations of Bryophytes Originating from Different Sites in Hokkaido, Northern Japan

    PubMed Central

    Jägerbrand, Annika K.; Kudo, Gaku

    2016-01-01

    There is limited knowledge available on the thermal acclimation processes for bryophytes, especially when considering variation between populations or sites. This study investigated whether short-term ex situ thermal acclimation of different populations showed patterns of site dependency and whether the maximum quantum yield of PSII (Fv/Fm) could be used as an indicator of adaptation or temperature stress in two bryophyte species: Pleurozium schreberi (Willd. ex Brid.) Mitt. and Racomitrium lanuginosum (Hedw.) Brid. We sought to test the hypothesis that differences in the ability to acclimate to short-term temperature treatment would be revealed as differences in photosystem II maximum yield (Fv/Fm). Thermal treatments were applied to samples from 12 and 11 populations during 12 or 13 days in growth chambers and comprised: (1) 10/5 °C; (2) 20/10 °C; (3) 25/15 °C; (4) 30/20 °C (12 hours day/night temperature). In Pleurozium schreberi, there were no significant site-dependent differences before or after the experiment, while site dependencies were clearly shown in Racomitrium lanuginosum throughout the study. Fv/Fm in Pleurozium schreberi decreased at the highest and lowest temperature treatments, which can be interpreted as a stress response, but no similar trends were shown by Racomitrium lanuginosum. PMID:27135242

  11. Variation in short-term and long-term responses of photosynthesis and isoprenoid-mediated photoprotection to soil water availability in four Douglas-fir provenances.

    PubMed

    Junker, Laura Verena; Kleiber, Anita; Jansen, Kirstin; Wildhagen, Henning; Hess, Moritz; Kayler, Zachary; Kammerer, Bernd; Schnitzler, Jörg-Peter; Kreuzwieser, Jürgen; Gessler, Arthur; Ensminger, Ingo

    2017-01-10

    For long-lived forest tree species, the understanding of intraspecific variation among populations and their response to water availability can reveal their ability to cope with and adapt to climate change. Dissipation of excess excitation energy, mediated by photoprotective isoprenoids, is an important defense mechanism against drought and high light when photosynthesis is hampered. We used 50-year-old Douglas-fir trees of four provenances at two common garden experiments to characterize provenance-specific variation in photosynthesis and photoprotective mechanisms mediated by essential and non-essential isoprenoids in response to soil water availability and solar radiation. All provenances revealed uniform photoprotective responses to high solar radiation, including increased de-epoxidation of photoprotective xanthophyll cycle pigments and enhanced emission of volatile monoterpenes. In contrast, we observed differences between provenances in response to drought, where provenances sustaining higher CO2 assimilation rates also revealed increased water-use efficiency, carotenoid-chlorophyll ratios, pools of xanthophyll cycle pigments, β-carotene and stored monoterpenes. Our results demonstrate that local adaptation to contrasting habitats affected chlorophyll-carotenoid ratios, pool sizes of photoprotective xanthophylls, β-carotene, and stored volatile isoprenoids. We conclude that intraspecific variation in isoprenoid-mediated photoprotective mechanisms contributes to the adaptive potential of Douglas-fir provenances to climate change.

  12. Variation in short-term and long-term responses of photosynthesis and isoprenoid-mediated photoprotection to soil water availability in four Douglas-fir provenances

    PubMed Central

    Junker, Laura Verena; Kleiber, Anita; Jansen, Kirstin; Wildhagen, Henning; Hess, Moritz; Kayler, Zachary; Kammerer, Bernd; Schnitzler, Jörg-Peter; Kreuzwieser, Jürgen; Gessler, Arthur; Ensminger, Ingo

    2017-01-01

    For long-lived forest tree species, the understanding of intraspecific variation among populations and their response to water availability can reveal their ability to cope with and adapt to climate change. Dissipation of excess excitation energy, mediated by photoprotective isoprenoids, is an important defense mechanism against drought and high light when photosynthesis is hampered. We used 50-year-old Douglas-fir trees of four provenances at two common garden experiments to characterize provenance-specific variation in photosynthesis and photoprotective mechanisms mediated by essential and non-essential isoprenoids in response to soil water availability and solar radiation. All provenances revealed uniform photoprotective responses to high solar radiation, including increased de-epoxidation of photoprotective xanthophyll cycle pigments and enhanced emission of volatile monoterpenes. In contrast, we observed differences between provenances in response to drought, where provenances sustaining higher CO2 assimilation rates also revealed increased water-use efficiency, carotenoid-chlorophyll ratios, pools of xanthophyll cycle pigments, β-carotene and stored monoterpenes. Our results demonstrate that local adaptation to contrasting habitats affected chlorophyll-carotenoid ratios, pool sizes of photoprotective xanthophylls, β-carotene, and stored volatile isoprenoids. We conclude that intraspecific variation in isoprenoid-mediated photoprotective mechanisms contributes to the adaptive potential of Douglas-fir provenances to climate change. PMID:28071755

  13. Short-term effects of endocrine-disrupting chemicals on the expression of estrogen-responsive genes in male medaka (Oryzias latipes).

    PubMed

    Yamaguchi, Akemi; Ishibashi, Hiroshi; Kohra, Shinya; Arizono, Koji; Tominaga, Nobuaki

    2005-04-30

    To evaluate the estrogenic activities of selected estrogenic compounds such as estradiol-17beta (E2), nonylphenol (NP), 4-(1-adamantyl)phenol (AdP), bisphenol A (BPA), BPA metabolite 4-methyl-2,4-bis(4-hydroxyphenyl)pent-1-ene (MBP) and 4,4'-dihydroxy-alpha-methylstilbene (DHMS) in the shortest possible time, we investigated the expression of estrogen-responsive genes such as vitellogenin I, vitellogenin II and alpha-type estrogen receptor genes in the liver of male medaka (Oryzias latipes) using reverse transcription-polymerase chain reaction (RT-PCR) techniques. These estrogen-responsive genes responded rapidly to selected estrogenic compounds after 8 h exposure, and the expression of hepatic vitellogenin II and estrogen receptor alpha mRNA was found to be more responsive than that of vitellogenin I mRNA. As a result, the relative estrogenic potencies of tested chemicals descended in the order of E2 (100)>MBP (0.38)>AdP (0.25)>DHMS (0.05)>NP (0.02)>BPA (0.001). Moreover, this preliminary study indicates that AdP and DHMS should be considered as candidate estrogenic compounds with the potential to induce hepatic estrogen-responsive genes in male medaka. These results suggest that vitellogenin I, vitellogenin II and estrogen receptor alpha gene expression patterns alter in male medaka treated with selected estrogenic compounds, and that these genes may be useful molecular biomarkers for screening estrogenic endocrine-disrupting chemicals in the shortest possible time.

  14. Short-term inhalation exposure to mild steel welding fume had no effect on lung inflammation and injury but did alter defense responses to bacteria in rats.

    PubMed

    Antonini, James M; Roberts, Jenny R; Stone, Sam; Chen, Bean T; Schwegler-Berry, Diane; Frazer, David G

    2009-02-01

    Many workers worldwide are continually exposed to complex aerosols generated from welding processes. The objective was to assess the effect of inhalation exposure to mild steel (MS) welding fume on lung injury, inflammation, and defense responses. Male Sprague-Dawley rats were exposed to MS fume at a concentration of 40 mg/m(3) x 3 h/day x 3 or 10 days using a robotic welding fume generator. Controls were exposed to filtered air. To assess lung defense responses, a group of animals were intratracheally inoculated with 5 x 10(4) Listeria monocytogenes 1 day after the last daily exposure. Welding particles were collected during exposure, and chemical composition and particle size were determined. After exposure, lung injury, inflammation, and host defense (bacterial clearance) were measured. The particles were composed of iron (80.6 %) and manganese (14.7 %) with a mass median aerodynamic diameter of 0.31 microm. No significant difference was observed in lung injury or inflammation after MS fume inhalation at 1, 4, and 11 days after the last exposure. However, there were significantly more bacteria at 3 days after infection in the lungs of the animals exposed to MS fume compared to air controls. Acute exposure of rats to MS fume had no effect on injury and inflammation, but suppressed lung defense responses after infection. More chronic inhalation studies are needed to further examine the immune effects and to elucidate the possible mechanisms of the suppressed lung defense response to infection associated with the inhalation of MS welding fume.

  15. Short-term response of different Saccharomyces cerevisiae strains to hyperosmotic stress caused by inoculation in grape must: RT-qPCR study and metabolite analysis.

    PubMed

    Noti, Olta; Vaudano, Enrico; Pessione, Enrica; Garcia-Moruno, Emilia

    2015-12-01

    During the winemaking process, glycerol synthesis represents the first adaption response of Saccharomyces cerevisiae to osmotic stress after inoculation in grape must. We have implemented an RT-qPCR (Reverse Transcription-quantitative PCR) methodology with a preventive evaluation of candidate reference genes, to study six target genes related to glycerol synthesis (GPD1, GPD2, GPP2 and GPP1) and flux (STL1 and FPS1), and three ALD genes coding for aldehyde dehydrogenase involved in redox equilibrium via acetate production. The mRNA level in three strains, characterized by different metabolite production, was monitored in the first 120 min from inoculation into natural grape must. Expression analysis shows a transient response of genes GPD1, GPD2, GPP2, GPP1 and STL1 with differences among strains in term of mRNA abundance, while FPS1 was expressed constitutively. The transient response and different expression intensity among strains, in relation to the intracellular glycerol accumulation pattern, prove the negative feedback control via the HOG (High Osmolarity Glycerol) signalling pathway in S. cerevisiae wine strains under winery conditions. Among the ALD genes, only ALD6 was moderately induced in the hyperosmotic environment but not in all strains tested, while ALD3 and ALD4 were drastically glucose repressed. The intensity of transcription of ALD6 and ALD3 seems to be related to different acetate production found among the strains.

  16. Effects of Short-Term Exposure to Particulate Air Pollutants on the Inflammatory Response and Respiratory Symptoms: A Panel Study in Schoolchildren from Rural Areas of Japan.

    PubMed

    Watanabe, Masanari; Noma, Hisashi; Kurai, Jun; Sano, Hiroyuki; Hantan, Degejirihu; Ueki, Masaru; Kitano, Hiroya; Shimizu, Eiji

    2016-09-30

    The relationship between particulate air pollutants and respiratory symptoms in children has not been consistent among studies, potentially owing to differences in the inflammatory response to different particulate air pollutants. This study aimed to investigate the effect of particulate air pollutants on respiratory symptoms and the inflammatory response in schoolchildren. Three hundred-and-sixty children were included in the study. The children recorded daily respiratory symptom scores for October 2015. In addition, the daily amount of interleukin (IL)-6, IL-8, and tumor necrosis factor (TNF)-α production was assessed in THP1 cells stimulated with suspended particulate matter (SPM), which was collected every day during the study period. Generalized estimating equation logistic regression analyses were used to estimate the associations among respiratory symptoms and the daily levels of SPM, IL-6, IL-8, and TNF-α. Daily SPM levels were not associated with respiratory symptoms or the daily IL-6, IL-8, and TNF-α levels. Conversely, there was a significant association between respiratory symptoms and the daily IL-6, IL-8, and TNF-α levels. These results suggested that the effects of particulate air pollutants on respiratory symptoms in schoolchildren might depend more on the pro-inflammatory response to them than on their mass concentration.

  17. Effects of Short-Term Exposure to Particulate Air Pollutants on the Inflammatory Response and Respiratory Symptoms: A Panel Study in Schoolchildren from Rural Areas of Japan

    PubMed Central

    Watanabe, Masanari; Noma, Hisashi; Kurai, Jun; Sano, Hiroyuki; Hantan, Degejirihu; Ueki, Masaru; Kitano, Hiroya; Shimizu, Eiji

    2016-01-01

    The relationship between particulate air pollutants and respiratory symptoms in children has not been consistent among studies, potentially owing to differences in the inflammatory response to different particulate air pollutants. This study aimed to investigate the effect of particulate air pollutants on respiratory symptoms and the inflammatory response in schoolchildren. Three hundred-and-sixty children were included in the study. The children recorded daily respiratory symptom scores for October 2015. In addition, the daily amount of interleukin (IL)-6, IL-8, and tumor necrosis factor (TNF)-α production was assessed in THP1 cells stimulated with suspended particulate matter (SPM), which was collected every day during the study period. Generalized estimating equation logistic regression analyses were used to estimate the associations among respiratory symptoms and the daily levels of SPM, IL-6, IL-8, and TNF-α. Daily SPM levels were not associated with respiratory symptoms or the daily IL-6, IL-8, and TNF-α levels. Conversely, there was a significant association between respiratory symptoms and the daily IL-6, IL-8, and TNF-α levels. These results suggested that the effects of particulate air pollutants on respiratory symptoms in schoolchildren might depend more on the pro-inflammatory response to them than on their mass concentration. PMID:27706066

  18. Short-Term Responses of Ground-Dwelling Beetles to Ice Storm-Induced Treefall Gaps in a Subtropical Broad-Leaved Forest in Southeastern China.

    PubMed

    Yu, Xiao-Dong; Liu, Chong-Ling; Lü, Liang; Luo, Tian-Hong; Zhou, Hong-Zhang

    2016-02-01

    Periodic natural disturbances shape the mosaic character of many landscapes and influence the distribution and abundance of organisms. In this study, we tested the effect of ice storm-induced treefall gaps on ground-dwelling beetle assemblages in different-aged successional stands of subtropical broad-leaved forest in southeastern China. We evaluated the relative importance of gap-phase microhabitat type (within gap, gap edge, and interior shaded) within different stand ages (regenerating stands and mature stands) as determinants of changes in beetle diversity and community structure. At 18 replicate sites sampled during 2009-2010, no significant differences were found in species richness and the abundances of the most common beetle species captured in pitfall traps among the three gap-phase microhabitat types, but the abundances of total beetles, as well as fungivorous and phytophagous species groups, were significantly lower in gap microhabitats than in interior shaded microhabitats in mature stands. Beetle assemblage composition showed no significant differences among the three microhabitat types, and only the fauna of gap plots slightly diverged from those of edge and shaded plots in mature stands. Cover of shrubs and stand age significantly affected beetle assemblage structure. Our results suggest that beetle responses to gap-phase dynamics in early successional forests are generally weak, and that effects are more discernible in the mature stands, perhaps due to the abundance responses of forest-specialist species.

  19. The effects of graded levels of calorie restriction: VI. Impact of short-term graded calorie restriction on transcriptomic responses of the hypothalamic hunger and circadian signaling pathways

    PubMed Central

    Green, Cara L.; Chen, Luonan; Han, Jing‐Dong J.; Wang, Yingchun; Promislow, Daniel E.L.; Lusseau, David; Speakman, John R.; Douglas, Alex

    2016-01-01

    Food intake and circadian rhythms are regulated by hypothalamic neuropeptides and circulating hormones, which could mediate the anti‐ageing effect of calorie restriction (CR). We tested whether these two signaling pathways mediate CR by quantifying hypothalamic transcripts of male C57BL/6 mice exposed to graded levels of CR (10 % to 40 %) for 3 months. We found that the graded CR manipulation resulted in upregulation of core circadian rhythm genes, which correlated negatively with circulating levels of leptin, insulin‐like growth factor 1 (IGF‐1), insulin, and tumor necrosis factor alpha (TNF‐α). In addition, key components in the hunger signaling pathway were expressed in a manner reflecting elevated hunger at greater levels of restriction, and which also correlated negatively with circulating levels of insulin, TNF‐α, leptin and IGF‐1. Lastly, phenotypes, such as food anticipatory activity and body temperature, were associated with expression levels of both hunger genes and core clock genes. Our results suggest modulation of the hunger and circadian signaling pathways in response to altered levels of circulating hormones, that are themselves downstream of morphological changes resulting from CR treatment, may be important elements in the response to CR, driving some of the key phenotypic outcomes. PMID:26945906

  20. The effects of graded levels of calorie restriction: VI. Impact of short-term graded calorie restriction on transcriptomic responses of the hypothalamic hunger and circadian signaling pathways.

    PubMed

    Derous, Davina; Mitchell, Sharon E; Green, Cara L; Chen, Luonan; Han, Jing-Dong J; Wang, Yingchun; Promislow, Daniel E L; Lusseau, David; Speakman, John R; Douglas, Alex

    2016-04-01

    Food intake and circadian rhythms are regulated by hypothalamic neuropeptides and circulating hormones, which could mediate the anti-ageing effect of calorie restriction (CR). We tested whether these two signaling pathways mediate CR by quantifying hypothalamic transcripts of male C57BL/6 mice exposed to graded levels of CR (10 % to 40 %) for 3 months. We found that the graded CR manipulation resulted in upregulation of core circadian rhythm genes, which correlated negatively with circulating levels of leptin, insulin-like growth factor 1 (IGF-1), insulin, and tumor necrosis factor alpha (TNF-α). In addition, key components in the hunger signaling pathway were expressed in a manner reflecting elevated hunger at greater levels of restriction, and which also correlated negatively with circulating levels of insulin, TNF-α, leptin and IGF-1. Lastly, phenotypes, such as food anticipatory activity and body temperature, were associated with expression levels of both hunger genes and core clock genes. Our results suggest modulation of the hunger and circadian signaling pathways in response to altered levels of circulating hormones, that are themselves downstream of morphological changes resulting from CR treatment, may be important elements in the response to CR, driving some of the key phenotypic outcomes.

  1. Physical and biological characterization of ferromagnetic fiber networks: effect of fibrin deposition on short-term in vitro responses of human osteoblasts.

    PubMed

    Spear, Rose L; Srigengan, Brajith; Neelakantan, Suresh; Bosbach, Wolfram; Brooks, Roger A; Markaki, Athina E

    2015-02-01

    Ferromagnetic fiber networks have the potential to deform in vivo imparting therapeutic levels of strain on in-growing periprosthetic bone tissue. 444 Ferritic stainless steel provides a suitable material for this application due to its ability to support cultures of human osteoblasts (HObs) without eliciting undue inflammatory responses from monocytes in vitro. In the present article, a 444 fiber network, containing 17 vol% fibers, has been investigated. The network architecture was obtained by applying a skeletonization algorithm to three-dimensional tomographic reconstructions of the fiber networks. Elastic properties were measured using low-frequency vibration testing, providing globally averaged properties as opposed to mechanical methods that yield only local properties. The optimal region for transduction of strain to cells lies between the ferromagnetic fibers. However, cell attachment, at early time points, occurs primarily on fiber surfaces. Deposition of fibrin, a fibrous protein involved in acute inflammatory responses, can facilitate cell attachment within this optimal region at early time points. The current work compared physiological (3 and 5 g·L(-1)) and supraphysiological fibrinogen concentrations (10 g·L(-1)), using static in vitro seeding of HObs, to determine the effect of fibrin deposition on cell responses during the first week of cell culture. Early cell attachment within the interfiber spaces was observed in all fibrin-containing samples, supported by fibrin nanofibers. Fibrin deposition influenced the seeding, metabolic activity, and early stage differentiation of HObs cultured in the fibrin-containing fiber networks in a concentration-dependant manner. While initial cell attachment for networks with fibrin deposited from low physiological concentrations was similar to control samples without fibrin deposition, significantly higher HObs attached onto high physiological and supraphysiological concentrations. Despite higher cell

  2. Physical and Biological Characterization of Ferromagnetic Fiber Networks: Effect of Fibrin Deposition on Short-Term In Vitro Responses of Human Osteoblasts

    PubMed Central

    Spear, Rose L.; Srigengan, Brajith; Neelakantan, Suresh; Bosbach, Wolfram; Brooks, Roger A.

    2015-01-01

    Ferromagnetic fiber networks have the potential to deform in vivo imparting therapeutic levels of strain on in-growing periprosthetic bone tissue. 444 Ferritic stainless steel provides a suitable material for this application due to its ability to support cultures of human osteoblasts (HObs) without eliciting undue inflammatory responses from monocytes in vitro. In the present article, a 444 fiber network, containing 17 vol% fibers, has been investigated. The network architecture was obtained by applying a skeletonization algorithm to three-dimensional tomographic reconstructions of the fiber networks. Elastic properties were measured using low-frequency vibration testing, providing globally averaged properties as opposed to mechanical methods that yield only local properties. The optimal region for transduction of strain to cells lies between the ferromagnetic fibers. However, cell attachment, at early time points, occurs primarily on fiber surfaces. Deposition of fibrin, a fibrous protein involved in acute inflammatory responses, can facilitate cell attachment within this optimal region at early time points. The current work compared physiological (3 and 5 g·L−1) and supraphysiological fibrinogen concentrations (10 g·L−1), using static in vitro seeding of HObs, to determine the effect of fibrin deposition on cell responses during the first week of cell culture. Early cell attachment within the interfiber spaces was observed in all fibrin-containing samples, supported by fibrin nanofibers. Fibrin deposition influenced the seeding, metabolic activity, and early stage differentiation of HObs cultured in the fibrin-containing fiber networks in a concentration-dependant manner. While initial cell attachment for networks with fibrin deposited from low physiological concentrations was similar to control samples without fibrin deposition, significantly higher HObs attached onto high physiological and supraphysiological concentrations. Despite higher cell

  3. Success of short-term, higher-dose imatinib mesylate to induce clinical response in FIP1L1-PDGFRalpha-negative hypereosinophilic syndrome.

    PubMed

    Butterfield, Joseph H

    2009-08-01

    Presence of the oncogenic mutation FIP1L1-PDGFRalpha in hypereosinophilic patients is predictive of hematologic response to imatinib mesylate. However, most patients with hypereosinophilic syndrome (HES) do not have this mutation and have not responded to imatinib doses traditionally successful in patients who test positive for FIP1L1-PDGFRalpha. A patient with FIP1L1-PDGFRalpha-negative HES who had intolerance of interferon alpha-2b and hydroxyurea was treated with escalating doses of imatinib. At 800 mg of imatinib daily, eosinophilia was controlled, allowing prednisone tapering and control of clinical and laboratory-detected abnormalities. HES patients who test negative for FIP1L1-PDGFRalpha may benefit from a trial of higher-dose imatinib.

  4. Unique genetic responses revealed in RNA-seq of the spleen of chickens stimulated with lipopolysaccharide and short-term heat

    PubMed Central

    Van Goor, Angelica; Ashwell, Chris M.; Persia, Michael E.; Rothschild, Max F.; Schmidt, Carl J.

    2017-01-01

    Climate change and disease have large negative impacts on poultry production, but little is known about the interactions of responses to these stressors in chickens. Fayoumi (heat and disease resistant) and broiler (heat and disease susceptible) chicken lines were stimulated at 22 days of age, using a 2x2x2 factorial design including: breed (Fayoumi or broiler), inflammatory stimulus (lipopolysaccharide (LPS) or saline), and temperature (35°C or 25°C). Transcriptional changes in spleens were analyzed using RNA-sequencing on the Illumina HiSeq 2500. Thirty-two individual cDNA libraries were sequenced (four per treatment) and an average of 22 million reads were generated per library. Stimulation with LPS induced more differentially expressed genes (DEG, log2 fold change ≥ 2 and FDR ≤ 0.05) in the broiler (N = 283) than the Fayoumi (N = 85), whereas heat treatment resulted in fewer DEG in broiler (N = 22) compared to Fayoumi (N = 107). The double stimulus of LPS+heat induced the largest numbers of changes in gene expression, for which broiler had 567 DEG and Fayoumi had 1471 DEG of which 399 were shared between breeds. Further analysis of DEG revealed pathways impacted by these stressors such as Remodelling of Epithelial Adherens Junctions due to heat stress, Granulocyte Adhesion and Diapedesis due to LPS, and Hepatic Fibrosis/Hepatic Stellate Cell Activation due to LPS+heat. The genes and pathways identified provide deeper understanding of the response to the applied stressors and may serve as biomarkers for genetic selection for heat and disease tolerant chickens. PMID:28166270

  5. Abdominal Pain (Stomach Pain), Short-Term

    MedlinePlus

    ... myhealthfinder Immunization Schedules Nutrient Shortfall Questionnaire Abdominal Pain (Stomach Pain), Short-termJust about everyone has had a " ... time or another. But sudden severe abdominal pain (stomach pain), also called acute pain, shouldn't be ...

  6. Rapid anthropogenic response to short-term aeolian-fluvial palaeoenvironmental changes during the Late Pleistocene-Holocene transition in the northern Negev Desert, Israel

    NASA Astrophysics Data System (ADS)

    Roskin, Joel; Katra, Itzhak; Agha, Nuha; Goring-Morris, A. Nigel; Porat, Naomi; Barzilai, Omry

    2014-09-01

    Archaeological investigations along Nahal Sekher on the eastern edge of Israel's northwestern Negev Desert dunefield revealed concentrations of Epipalaeolithic campsites associated respectively with ancient water bodies. This study, aimed at better understanding the connections between these camps and the water bodies, is concerned with a cluster of Natufian sites. A comprehensive geomorphological study integrating field mapping, stratigraphic sections, sedimentological analysis and optically stimulated luminescence (OSL) ages was conducted in the vicinity of a recently excavated Natufian campsite of Nahal Sekher VI whose artifacts directly overlay aeolian sand dated by OSL to 12.4 ± 0.7 and 11.7 ± 0.5 ka. Residual sequences of diagnostic silty sediments, defined here as low-energy fluvial fine-grained deposits (LFFDs), were identified within the drainage system of central Nahal Sekher around the Nahal Sekher VI site. LFFD sections were found to represent both shoreline and mid-water deposits. The thicker mid-water LFFD deposits (15.7 ± 0.7-10.7 ± 0.5 ka) date within the range of the Epipalaeolithic campsites, while the upper and shoreline LFFD units that thin out into the sands adjacent to the Nahal Sekher VI site display slightly younger ages (10.8 ± 0.4 ka-7.6 ± 0.4 ka). LFFD sedimentation by low-energy concentrated flow and standing-water developed as a result of proximal downstream dune-damming. These water bodies developed as a result of encroaching sand that initially crossed central Nahal Sekher by 15.7 ± 0.7 ka and probably intermittently blocked the course of the wadi. LFFD deposition was therefore a response to a unique combination of regional sand supply due to frequent powerful winds and does not represent climate change in the form of increased precipitation or temperature change. The chronostratigraphies affiliate the Natufian sites to the adjacent ancient water bodies. These relations reflect a rapid, but temporary anthropogenic response to a

  7. Short-term metallothionein inductions in the edible cockle Cerastoderma edule after cadmium or mercury exposure: discrepancy between mRNA and protein responses.

    PubMed

    Paul-Pont, Ika; Gonzalez, Patrice; Baudrimont, Magalie; Nili, Hanane; de Montaudouin, Xavier

    2010-05-05

    Metallothioneins (MT) are essential metal binding proteins involved in metal homeostasis and detoxification in living organisms. Numerous studies have focused on MT response to metal exposure and showed an important variability according to species, metal, concentration and time of exposure. In this study, the expression of one isoform of MT gene (Cemt1) and associated MT protein synthesis were determined after 1, 3, 9, 24, 72 and 168h of cadmium (Cd) or mercury (Hg) exposures in gills of the cockle Cerastoderma edule. This experiment, carried out in laboratory conditions, revealed that in Cd-exposed cockles, induction of Cemt1 is time-dependent following a "pulse-scheme" with significant upregulation at 24h and 168h intersected by time point (72h) with significant downregulation. MT protein concentration increases with time in gills of exposed cockles in relation with the progressive accumulation of Cd in soluble fraction. On contrary, Hg exposure does not lead to any induction of Cemt1 mRNA expression or MT protein synthesis compared to control, despite a higher accumulation of this metal in gills of cockles compared to Cd. The localization of Hg (85-90%) is in insoluble fraction, whereas MT was located in the cytoplasm of cells. This gives us a first clue to understand the inability of Hg to activate MT synthesis. However, other biochemical processes probably occur in gills of C. edule since the remaining soluble fraction of Hg exceeds MT sequestration ability. Finally, since one of the first main targets of metal toxicity in cells was the mitochondria, some genes involved in mitochondria metabolism were also analyzed in order to assess potential differences in cellular damages between two metal exposures. Indeed, until T(168), no impact on mitochondrial genes was shown following Hg exposure, despite the complete lack of MT response. This result indicated the presence of other effective cellular ligands which sequester the cytosolic fraction of this metal and

  8. Response of Lemna minor L. to short-term cobalt exposure: The effect on photosynthetic electron transport chain and induction of oxidative damage.

    PubMed

    Begović, Lidija; Mlinarić, Selma; Antunović Dunić, Jasenka; Katanić, Zorana; Lončarić, Zdenko; Lepeduš, Hrvoje; Cesar, Vera

    2016-06-01

    The effect of two concentrations of cobalt (Co(2+)) on photosynthetic activity and antioxidative response in Lemna minor L. were assessed 24, 48 and 72h after the start of the exposure. Higher concentration of cobalt (1mM) induced growth inhibition while lower concentration (0.01mM) increased photosynthetic pigments content. Analysis of chlorophyll a fluorescence transients revealed high sensitivity of photosystem II primary photochemistry to excess of Co(2+) especially at the higher concentration where decreased electron transport beyond primary quinone acceptor QA(-) and impaired function of oxygen evolving complex (OEC) was observed. Due to impairment of OEC, oxygen production was decreased at higher Co(2+) concentration. Activity of superoxide dismutase was mainly inhibited while lipid peroxidation increased, at both concentrations, indicating that cobalt-induced oxidative damage after short exposure and moreover, susceptibility of the membranes in the cell to cobalt toxicity. Results obtained in this study suggest possible application of used parameters as tools in assessment of early damage caused by metals.

  9. Short-term emissions of CO2 and N2O in response to periodic flood irrigation with waste water in the Mezquital Valley of Mexico

    NASA Astrophysics Data System (ADS)

    González-Méndez, B.; Webster, R.; Fiedler, S.; Loza-Reyes, E.; Hernández, J. M.; Ruíz-Suárez, L. G.; Siebe, C.

    2015-01-01

    Irrigation with waste water adds labile carbon and nitrogen compounds to the soil, and when applied by flooding it rapidly changes the soil's atmosphere and redox potential. In the Mezquital Valley more than 90 000 ha is irrigated with waste water from Mexico City, and enhanced emissions of CO2 and N2O follow each flooding. We measured the emissions of these two gases from a field irrigated periodically with waste water and under three crops, namely alfalfa, rye-grass and maize, using static chambers for 21 months. We also measured emissions from a field growing rain-fed maize before and shortly after two rain events. The data from repeated measurements from the same chambers are correlated in time, and so we modelled the ante-dependence and fitted the models by residual maximum likelihood (REML). The emissions of both CO2 and N2O increased rapidly in response to flood irrigation with peaks up to 448 mg C m-2 hour-1 for CO2 and 2.98 mg N m-2 hour-1 for N2O under maize. Emissions peaked in particular irrigation events either as the infiltrating water replaced the gas from air-filled pores or several days after irrigation as excess nitrogen and fresh sources of carbon were mineralized. Processes operating during the few days during and immediately after irrigation seem to determine the dynamics of gaseous production in this agricultural ecosystem.

  10. Responses of ecosystem CO 2 fluxes to short-term experimental warming and nitrogen enrichment in an Alpine meadow, northern Tibet Plateau.

    PubMed

    Zong, Ning; Shi, Peili; Jiang, Jing; Song, Minghua; Xiong, Dingpeng; Ma, Weiling; Fu, Gang; Zhang, Xianzhou; Shen, Zhenxi

    2013-01-01

    Over the past decades, the Tibetan Plateau has experienced pronounced warming, yet the extent to which warming will affect alpine ecosystems depends on how warming interacts with other influential global change factors, such as nitrogen (N) deposition. A long-term warming and N manipulation experiment was established to investigate the interactive effects of warming and N deposition on alpine meadow. Open-top chambers were used to simulate warming. N addition, warming, N addition × warming, and a control were set up. In OTCs, daytime air and soil temperature were warmed by 2.0°C and 1.6°C above ambient conditions, but soil moisture was decreased by 4.95 m(3) m(-3). N addition enhanced ecosystem respiration (Reco); nevertheless, warming significantly decreased Reco. The decline of Reco resulting from warming was cancelled out by N addition in late growing season. Our results suggested that N addition enhanced Reco by increasing soil N availability and plant production, whereas warming decreased Reco through lowering soil moisture, soil N supply potential, and suppression of plant activity. Furthermore, season-specific responses of Reco indicated that warming and N deposition caused by future global change may have complicated influence on carbon cycles in alpine ecosystems.

  11. Immediate List Recall as a Measure of Short-Term Episodic Memory: Insights from the Serial Position Effect and Item Response Theory

    PubMed Central

    Gavett, Brandon E.; Horwitz, Julie E.

    2012-01-01

    The serial position effect shows that two interrelated cognitive processes underlie immediate recall of a supraspan word list. The current study used item response theory (IRT) methods to determine whether the serial position effect poses a threat to the construct validity of immediate list recall as a measure of verbal episodic memory. Archival data were obtained from a national sample of 4,212 volunteers aged 28–84 in the Midlife Development in the United States study. Telephone assessment yielded item-level data for a single immediate recall trial of the Rey Auditory Verbal Learning Test (RAVLT). Two parameter logistic IRT procedures were used to estimate item parameters and the Q1 statistic was used to evaluate item fit. A two-dimensional model better fit the data than a unidimensional model, supporting the notion that list recall is influenced by two underlying cognitive processes. IRT analyses revealed that 4 of the 15 RAVLT items (1, 12, 14, and 15) were misfit (p < .05). Item characteristic curves for items 14 and 15 decreased monotonically, implying an inverse relationship between the ability level and the probability of recall. Elimination of the four misfit items provided better fit to the data and met necessary IRT assumptions. Performance on a supraspan list learning test is influenced by multiple cognitive abilities; failure to account for the serial position of words decreases the construct validity of the test as a measure of episodic memory and may provide misleading results. IRT methods can ameliorate these problems and improve construct validity. PMID:22138320

  12. Multiple biomarker responses in Prochilodus lineatus subjected to short-term in situ exposure to streams from agricultural areas in Southern Brazil.

    PubMed

    Vieira, Carlos Eduardo Delfino; Costa, Patrícia Gomes; Lunardelli, Bruna; de Oliveira, Luciana Fernandes; Cabrera, Liziara da Costa; Risso, Wagner Ezequiel; Primel, Ednei Gilberto; Meletti, Paulo César; Fillmann, Gilberto; Martinez, Claudia Bueno dos Reis

    2016-01-15

    In order to assess the quality of streams susceptible to contamination by pesticides we apply biochemical and genotoxic biomarkers in the Neotropical fish Prochilodus lineatus submitted to in situ tests. Fish were caged, for 96 h, in two streams located in areas with intensive use of pesticides, the Apertados (AP) and the Jacutinga (JC), and in a small stream (Godoy stream — GD) found inside a forest fragment adjacent to a State Park. Biochemical parameters, such as biotransformation enzymes 7-ethoxyresorufin-O-deethylase (EROD) and glutathione-S-transferase (GST), non-protein thiols (NPSH), lipoperoxidation (LPO), protein carbonylation (PCO) and acetylcholinesterase (AChE) were evaluated in various fish organs, as well as genotoxic biomarkers (damage to DNA and occurrence of micronuclei and erythrocyte nuclear abnormalities). Samples of water and sediment were collected for analysis of metals (Cu, Cr, Pb, Ni, Mn, Cd and Zn), organochloride pesticides, and triazine and glyphosate herbicides. We observed an increase in liver GST activity in fish at AP and gill GST activity in fish at JC. An increase in liver LPO was also observed in fish exposed to AP and JC. The same animals also exhibited increased DNA damage and erythrocyte nuclear abnormalities (ENAs) compared to the fish kept in GD. A number of compounds showed concentrations higher than the permitted levels, in particular, dichlorodiphenyltrichloroethane (DDT), its metabolites dichlorodiphenyldichloroethylene (DDE) and dichlorodiphenyldichloroethane (DDD), hexachlorocyclohexanes (HCH), heptachloride, diclofluanid and aldrins. These pesticides were detected at higher concentrations in water and sediment samples from AP, followed by JC and GD. The Integrated Biomarker Response Index (IBR) indicated that AP and JC (AP: 21.7 > JC: 18.5 > GD: 12.6) have the worst environmental quality. Integrated biomarker analysis revealed that the alterations observed related well with the levels of environmental contaminants

  13. Short-Term Responses of Soil Respiration and C-Cycle Enzyme Activities to Additions of Biochar and Urea in a Calcareous Soil

    PubMed Central

    Song, Dali; Xi, Xiangyin; Huang, Shaomin; Liang, Guoqing; Sun, Jingwen; Zhou, Wei; Wang, Xiubin

    2016-01-01

    Biochar (BC) addition to soil is a proposed strategy to enhance soil fertility and crop productivity. However, there is limited knowledge regarding responses of soil respiration and C-cycle enzyme activities to BC and nitrogen (N) additions in a calcareous soil. A 56-day incubation experiment was conducted to investigate the combined effects of BC addition rates (0, 0.5, 1.0, 2.5 and 5.0% by mass) and urea (U) application on soil nutrients, soil respiration and C-cycle enzyme activities in a calcareous soil in the North China Plain. Our results showed soil pH values in both U-only and U plus BC treatments significantly decreased within the first 14 days and then stabilized, and CO2emission rate in all U plus BC soils decreased exponentially, while there was no significant difference in the contents of soil total organic carbon (TOC), dissolved organic carbon (DOC), total nitrogen (TN), and C/N ratio in each treatment over time. At each incubation time, soil pH, electrical conductivity (EC), TOC, TN, C/N ratio, DOC and cumulative CO2 emission significantly increased with increasing BC addition rate, while soil potential activities of the four hydrolytic enzymes increased first and then decreased with increasing BC addition rate, with the largest values in the U + 1.0%BC treatment. However, phenol oxidase activity in all U plus BC soils showed a decreasing trend with the increase of BC addition rate. Our results suggest that U plus BC application at a rate of 1% promotes increases in hydrolytic enzymes, does not highly increase C/N and C mineralization, and can improve in soil fertility. PMID:27589265

  14. Responses of fine roots and soil N availability to short-term nitrogen fertilization in a broad-leaved Korean pine mixed forest in northeastern China.

    PubMed

    Wang, Cunguo; Han, Shijie; Zhou, Yumei; Yan, Caifeng; Cheng, Xubing; Zheng, Xingbo; Li, Mai-He

    2012-01-01

    Knowledge of the responses of soil nitrogen (N) availability, fine root mass, production and turnover rates to atmospheric N deposition is crucial for understanding fine root dynamics and functioning in forest ecosystems. Fine root biomass and necromass, production and turnover rates, and soil nitrate-N and ammonium-N in relation to N fertilization (50 kg N ha(-1) year(-1)) were investigated in a temperate forest over the growing season of 2010, using sequential soil cores and ingrowth cores methods. N fertilization increased soil nitrate-N by 16% (P<0.001) and ammonium-N by 6% (P<0.01) compared to control plots. Fine root biomass and necromass in 0-20 cm soil were 13% (4.61 vs. 5.23 Mg ha(-1), P<0.001) and 34% (1.39 vs. 1.86 Mg ha(-1), P<0.001) less in N fertilization plots than those in control plots. The fine root mass was significantly negatively correlated with soil N availability and nitrate-N contents, especially in 0-10 cm soil layer. Both fine root production and turnover rates increased with N fertilization, indicating a rapid underground carbon cycling in environment with high nitrogen levels. Although high N supply has been widely recognized to promote aboveground growth rates, the present study suggests that high levels of nitrogen supply may reduce the pool size of the underground carbon. Hence, we conclude that high levels of atmospheric N deposition will stimulate the belowground carbon cycling, leading to changes in the carbon balance between aboveground and underground storage. The implications of the present study suggest that carbon model and prediction need to take the effects of nitrogen deposition on underground system into account.

  15. Short-Term Behavioural Responses of the Great Scallop Pecten maximus Exposed to the Toxic Alga Alexandrium minutum Measured by Accelerometry and Passive Acoustics

    PubMed Central

    Coquereau, Laura; Jolivet, Aurélie; Hégaret, Hélène; Chauvaud, Laurent

    2016-01-01

    Harmful algal blooms produced by toxic dinoflagellates have increased worldwide, impacting human health, the environment, and fisheries. Due to their potential sensitivity (e.g., environmental changes), bivalves through their valve movements can be monitored to detect harmful algal blooms. Methods that measure valve activity require bivalve-attached sensors and usually connected cables to data transfers, leading to stress animals and limit the use to sessile species. As a non-intrusive and continuously deployable tool, passive acoustics could be an effective approach to detecting harmful algal blooms in real time based on animal sound production. This study aimed to detect reaction changes in the valve movements of adult Pecten maximus exposed to the toxic dinoflagellate Alexandrium minutum using both accelerometry and passive acoustic methods. Scallops were experimentally exposed to three ecologically relevant concentrations of A. minutum for 2 hours. The number of each type of valve movement and their sound intensity, opening duration, and valve-opening amplitude were measured. Four behaviours were identified: closures, expulsion, displacement, and swimming. The response of P. maximus to A. minutum occurred rapidly at a high concentration. The valve activity of P. maximus was different when exposed to high concentrations (500 000 cells L-1) of A. minutum compared to the non-toxic dinoflagellate Heterocapsa triquetra; the number of valve movements increased, especially closure and expulsion, which were detected acoustically. Thus, this study demonstrates the potential for acoustics and sound production changes in the detection of harmful algal blooms. However, field trials and longer duration experiments are required to provide further evidence for the use of acoustics as a monitoring tool in the natural environment where several factors may interfere with valve behaviours. PMID:27508498

  16. Effect of timing of challenge following short-term natural exposure to bovine viral diarrhea virus type 1b on animal performance and immune response in beef steers.

    PubMed

    Carlos-Valdez, L; Wilson, B K; Burciaga-Robles, L O; Step, D L; Holland, B P; Richards, C J; Montelongo, M A; Confer, A W; Fulton, R W; Krehbiel, C R

    2016-11-01

    response associated with BRD. As typical beef cattle marketing channels allow for variation in the timing of respiratory pathogen exposure, understanding the physiological changes in morbid cattle will lead to improved management of BRD.

  17. Impaired short-term memory for pitch in congenital amusia.

    PubMed

    Tillmann, Barbara; Lévêque, Yohana; Fornoni, Lesly; Albouy, Philippe; Caclin, Anne

    2016-06-01

    Congenital amusia is a neuro-developmental disorder of music perception and production. The hypothesis is that the musical deficits arise from altered pitch processing, with impairments in pitch discrimination (i.e., pitch change detection, pitch direction discrimination and identification) and short-term memory. The present review article focuses on the deficit of short-term memory for pitch. Overall, the data discussed here suggest impairments at each level of processing in short-term memory tasks; starting with the encoding of the pitch information and the creation of the adequate memory trace, the retention of the pitch traces over time as well as the recollection and comparison of the stored information with newly incoming information. These impairments have been related to altered brain responses in a distributed fronto-temporal network, associated with decreased connectivity between these structures, as well as in abnormalities in the connectivity between the two auditory cortices. In contrast, amusic participants׳ short-term memory abilities for verbal material are preserved. These findings show that short-term memory deficits in congenital amusia are specific to pitch, suggesting a pitch-memory system that is, at least partly, separated from verbal memory. This article is part of a Special Issue entitled SI: Auditory working memory.

  18. Skeletal response to short-term weightlessness

    NASA Technical Reports Server (NTRS)

    Wronski, T. J.; Morey-Holton, E. R.

    1986-01-01

    Male Sprague Dawley rats were placed in orbit for 7 days aboard the space shuttle. Bone histomorphometry was performed in the long bones and lumbar vertebrae of flight rats and compared to data derived from ground based control rats. Trabecular bone mass was not altered during the first week of weightlessness. Strong trends were observed in flight rats for decreased periosteal bone formation in the tibial diaphysis, reduced osteoblast size in the proximal tibia, and decreased osteoblast surface and number in the lumbar vertebra. Histologic indices of bone resorption was relatively normal in flight rats. The results indicate that 7 day of weightlessness are not of sufficient duration to induce histologicaly detectable loss of trabecular bone in rats. However, cortical and trabecular bone formation appear to be diminished during the first week of space flight.

  19. Mutations of Cytochrome b559 and PsbJ on and near the QC Site in Photosystem II Influence the Regulation of Short-Term Light Response and Photosynthetic Growth of the Cyanobacterium Synechocystis sp. PCC 6803.

    PubMed

    Huang, Jine-Yung; Chiu, Yi-Fang; Ortega, José M; Wang, Hsing-Ting; Tseng, Tien-Sheng; Ke, Shyue-Chu; Roncel, Mercedes; Chu, Hsiu-An

    2016-04-19

    The characteristic features of two types of short-term light adaptations of the photosynthetic apparatus of the cyanobacterium Synechocystis sp. PCC 6803, state transition and blue-green light-induced fluorescence quenching, were compared in wild-type and cytochrome b559 and PsbJ mutant cells with mutations on and near the QC site in photosystem II (PSII). All mutant cells grew photoautotrophically and assembled stable PSII. Thermoluminescence emission experiments showed a decrease in the stability of the S3QB(-)/S2QB(-) charge pairs in the A16FJ, S28Aβ, and V32Fβ mutant cells. When dark-adapted wild-type and mutant cells were illuminated by medium-intensity blue light, the increase in the PSII fluorescence yield (indicating a transition to state 1) was more prominent in mutant than wild-type cells. Strong blue-light conditions induced a quenching of fluorescence corresponding to nonphotochemical fluorescence quenching (NPQ). The extension of NPQ decreased significantly in the mutants, and the kinetics appeared to be affected. When similar measures were repeated on an orange carotenoid protein (OCP)-deficient background, little or no quenching was observed, which confirms that the decrease in fluorescence under strong blue light corresponded to the OCP-dependent NPQ. Immunoblot results showed that the attenuated effect of blue light-induced NPQ in mutant cells was not due to a lack of OCP. Photosynthetic growth and biomass production were greater for A16FJ, S28Aβ, and V32Fβ mutant cells than for wild-type cells under normal growth conditions. Our results suggest that mutations of cytochrome b559 and PsbJ on and near the QC site of PSII may modulate the short-term light response in cyanobacteria.

  20. Short-term memory across eye blinks.

    PubMed

    Irwin, David E

    2014-01-01

    The effect of eye blinks on short-term memory was examined in two experiments. On each trial, participants viewed an initial display of coloured, oriented lines, then after a retention interval they viewed a test display that was either identical or different by one feature. Participants kept their eyes open throughout the retention interval on some blocks of trials, whereas on others they made a single eye blink. Accuracy was measured as a function of the number of items in the display to determine the capacity of short-term memory on blink and no-blink trials. In separate blocks of trials participants were instructed to remember colour only, orientation only, or both colour and orientation. Eye blinks reduced short-term memory capacity by approximately 0.6-0.8 items for both feature and conjunction stimuli. A third, control, experiment showed that a button press during the retention interval had no effect on short-term memory capacity, indicating that the effect of an eye blink was not due to general motoric dual-task interference. Eye blinks might instead reduce short-term memory capacity by interfering with attention-based rehearsal processes.

  1. Short-term energy outlook: Methodology

    NASA Astrophysics Data System (ADS)

    Cornett, C.; Paxson, D.; Reznek, A. P.; Chu, C.; Sitzer, S.; Gamson, N.; Childress, J. P.; Paul, S.; Weigel, H.; Sutton, S.

    1981-05-01

    Detailed discussions of forecasting methodology and analytical topics concerning short-term energy markets are presented. Major assumptions necessary to make the energy forecasts are also discussed. Supplementary analyses of topics related to short-term energy forecasting are also given. The discussions relate to the forecasts prepared using the short term integrated forecasting system. This set of computer models uses data from various sources to develop energy supply and demand balances. Econmetric models used to predict the demand for petroleum products, natural gas, coal, and electricity are discussed. Price prediction models are also discussed. The role of oil inventories in world oil markets is reviewed. Various relationship between weather patterns and energy consumption are discussed.

  2. Metropolitan French: Familiarization & Short-Term Training.

    ERIC Educational Resources Information Center

    Iszkowski, Marie-Charlotte

    The U.S. Department of State's Foreign Service Institute French Familiarization and Short-Term (FAST) course for personnel working and living in France consists of 10 weeks of French language instruction combined with practical and cultural information. An introductory section outlines FAST course objectives and sample teaching techniques in…

  3. Spanish: Familiarization and Short-Term Training.

    ERIC Educational Resources Information Center

    Arbelaez, Vicente; And Others

    The State Department's Foreign Service Institute short-term, intensive course in Spanish language and culture for government employees going to work in Spanish-speaking countries contains an introductory section and 38 lessons and 10 related audio cassettes intended as the basis for a ten-week program with an instructor. The lessons cover these…

  4. Short-Term Play Therapy for Children.

    ERIC Educational Resources Information Center

    Kaduson, Heidi Gerard, Ed.; Schaefer, Charles E., Ed.

    Play therapy offers a powerful means of helping children resolve a wide range of psychological difficulties, and many play approaches are ideally suited to short-term work. This book brings together leading play therapists to share their expertise on facilitating children's healing in a shorter time frame. The book provides knowledge and skills…

  5. The pattern of LH secretion and the ovarian response to the 'ram effect' in the anoestrous ewe is influenced by body condition but not by short-term nutritional supplementation.

    PubMed

    Scaramuzzi, R J; Oujagir, L; Menassol, J-B; Freret, S; Piezel, A; Brown, H M; Cognié, J; Fabre Nys, C

    2014-10-01

    In sheep, the 'ram effect' induces out-of-season fertility and good nutrition increases prolificacy. This experiment determined if fatness or short-term nutritional supplementation modified the response to the 'ram effect'. A group of 48 Île-de-France ewes were fed diets that produced groups with body-condition scores (BCS) of >3.0 and <2.0. Within each BCS group animals were supplemented daily with 500g of lupins from Day -5 to Day 0 (ram introduction) resulting in four groups: low BCS, supplemented (n=7) and non-supplemented (n=8) and high BCS, supplemented (n=12) and non-supplemented (n=11). The blood concentrations of glucose and insulin and the LH response to gonadotrophin-releasing hormone (GnRH) were determined. After the 'ram effect' the pattern of LH pulsatility, the LH surge and ovarian responses were analysed. Low BCS ewes had lower glucose and insulin (P<0.001) and supplementation increased both (P≤0.001). The increase in LH induced by GnRH was reduced in low BCS ewes (P=0.015) but it was not affected by supplementation. Similarly, LH pulsatility was reduced in low BCS ewes (P<0.05). The LH surge and ovarian cyclicity were not affected but the follow-up cycle was delayed (P=0.034) and progesterone was reduced (P=0.029) in low BCS ewes. There was an effect of BCS on ovulation rate (P<0.05). These results show that the BCS can modify the response to the 'ram effect' and that supplementation has little effect on this response.

  6. Response of Chloroplast NAD(P)H Dehydrogenase-Mediated Cyclic Electron Flow to a Shortage or Lack in Ferredoxin-Quinone Oxidoreductase-Dependent Pathway in Rice Following Short-Term Heat Stress

    PubMed Central

    Essemine, Jemaa; Qu, Mingnan; Mi, Hualing; Zhu, Xin-Guang

    2016-01-01

    Cyclic electron flow (CEF) around photosystem I (PSI) can protect photosynthetic electron carriers under conditions of stromal over-reduction. The goal of the research reported in this paper was to investigate the responses of both PSI and photosystem II (PSII) to a short-term heat stress in two rice lines with different capacities of cyclic electron transfer, i.e., Q4149 with a high capacity (hcef) and C4023 with a low capacity (lcef). The absorbance change at 820 nm (ΔA820) was used here to assess the charge separation in the PSI reaction center (P700). The results obtained show that short-term heat stress abolishes the ferredoxin-quinone oxidoreductase (FQR)-dependent CEF in rice and accelerates the initial rate of P700+ re-reduction. The P700+ amplitude was slightly increased at a moderate heat-stress (35°C) because of a partial restriction of FQR but it was decreased following high heat-stress (42°C). Assessment of PSI and PSII activities shows that PSI is more susceptible to heat stress than PSII. Under high temperature, FQR-dependent CEF was completely removed and NDH-dependent CEF was up-regulated and strengthened to a higher extent in C4023 than in Q4149. Specifically, under normal growth temperature, hcef (Q4149) was characterized by higher FQR- and chloroplast NAD(P)H dehydrogenase (NDH)-dependent CEF rates than lcef (C4023). Following thermal stress, the activation of NDH-pathway was 130 and 10% for C4023 and Q4149, respectively. Thus, the NDH-dependent CEF may constitute the second layer of plant protection and defense against heat stress after the main route, i.e., FQR-dependent CEF, reaches its capacity. We discuss the possibility that under high heat stress, the NDH pathway serves as a safety valve to dissipate excess energy by cyclic photophosphorylation and overcome the stroma over-reduction following inhibition of CO2 assimilation and any shortage or lack in the FQR pathway. The potential role of the NDH-dependent pathway during the evolution

  7. Short-term, high-fat overfeeding impairs glycaemic control but does not alter gut hormone responses to a mixed meal tolerance test in healthy, normal-weight individuals.

    PubMed

    Parry, Siôn A; Smith, Jennifer R; Corbett, Talitha R B; Woods, Rachel M; Hulston, Carl J

    2017-01-01

    Obesity is undoubtedly caused by a chronic positive energy balance. However, the early metabolic and hormonal responses to overeating are poorly described. This study determined glycaemic control and selected gut hormone responses to nutrient intake before and after 7 d of high-fat overfeeding. Nine healthy individuals (five males, four females) performed a mixed meal tolerance test (MTT) before and after consuming a high-fat (65 %), high-energy (+50 %) diet for 7 d. Measurements of plasma glucose, NEFA, acylated ghrelin, glucagon-like peptide-1 (GLP-1), gastric inhibitory polypeptide (GIP) and serum insulin were taken before (fasting) and at 30-min intervals throughout the 180-min MTT (postprandial). Body mass increased by 0·79 (sem 0·14) kg after high-fat overfeeding (P<0·0001), and BMI increased by 0·27 (sem 0·05) kg/m2 (P=0·002). High-fat overfeeding also resulted in an 11·6 % increase in postprandial glucose AUC (P=0·007) and a 25·9 % increase in postprandial insulin AUC (P=0·005). Acylated ghrelin, GLP-1 and GIP responses to the MTT were all unaffected by the high-fat, high-energy diet. These findings demonstrate that even brief periods of overeating are sufficient to disrupt glycaemic control. However, as the postprandial orexigenic (ghrelin) and anorexigenic/insulintropic (GLP-1 and GIP) hormone responses were unaffected by the diet intervention, it appears that these hormones are resistant to short-term changes in energy balance, and that they do not play a role in the rapid reduction in glycaemic control.

  8. A Short-Term Incubation with High Glucose Impairs VASP Phosphorylation at Serine 239 in response to the Nitric Oxide/cGMP Pathway in Vascular Smooth Muscle Cells: Role of Oxidative Stress

    PubMed Central

    Russo, Isabella; Viretto, Michela; Doronzo, Gabriella; Barale, Cristina; Mattiello, Luigi; Anfossi, Giovanni; Trovati, Mariella

    2014-01-01

    A reduction of the nitric oxide (NO) action in vascular smooth muscle cells (VSMC) could play a role in the vascular damage induced by the glycaemic excursions occurring in diabetic patients; in this study, we aimed to clarify whether a short-term incubation of cultured VSMC with high glucose reduces the NO ability to increase cGMP and the cGMP ability to phosphorylate VASP at Ser-239. We observed that a 180 min incubation of rat VSMC with 25 mmol/L glucose does not impair the NO-induced cGMP increase but reduces VASP phosphorylation in response to both NO and cGMP with a mechanism blunted by antioxidants. We further demonstrated that high glucose increases radical oxygen species (ROS) production and that this phenomenon is prevented by the PKC inhibitor chelerythrine and the NADPH oxidase inhibitor apocynin. The following sequence of events is supported by these results: (i) in VSMC high glucose activates PKC; (ii) PKC activates NADPH oxidase; (iii) NADPH oxidase induces oxidative stress; (iv) ROS impair the signalling of cGMP, which is involved in the antiatherogenic actions of NO. Thus, high glucose, via oxidative stress, can reduce the cardiovascular protection conferred by the NO/cGMP pathway via phosphorylation of the cytoskeleton protein VASP in VSMC. PMID:24779009

  9. The economics of short-term leasing.

    PubMed

    Flath, D

    1980-04-01

    Short-term leasing is an everyday occurrence. Tax savings cannot account for the ubiquity of leasing by temporary users. Monopoly explanations are inconsistent with concurrent leasing and selling markets for perfect substitutes. Leasing economizes upon the costs of detecting, assuring, and maintaining quality, costs of search, and costs of risk-bearing. This view is based on standard economic reasoning and has numerous specific implications.

  10. Short-term changes in beach morphology on Louisiana coast

    SciTech Connect

    Nakashima, L.D.

    1988-09-01

    A study of the short-term response of seven shoreline segments between the Sabine River and Sandy Point is based on data from a three-year coastal erosion monitoring project. Seventy-eight beach-profile transects were surveyed quarterly between December 1985 and March 1988 to determine their patterns and rates of shoreline change. Efforts were made to characterize straight and curved shorelines as well as those that have been artificially stabilized.

  11. Item repetition in short-term memory: Ranschburg repeated.

    PubMed

    Henson, R N

    1998-09-01

    In serial recall from short-term memory, repeated items are recalled well when close together (repetition facilitation), but not when far apart (repetition inhibition; the Ranschburg effect). These effects were re-examined with a new scoring scheme that addresses the possibility that repetitions are distinct tokens in memory. Repetition facilitation and repetition inhibition proved robust, and were shown to interact with the temporal grouping of items (Experiment 1), which affected the probability of detecting repetition (Experiments 2A and 2B). It is argued that detection of a repetition is necessary for repetition facilitation, attributable to the tagging of immediate repetition, whereas the failure to detect or remember a repetition results in repetition inhibition, attributable to an automatic suppression of previous responses and a bias against guessing repeated items (Experiment 3). The findings are discussed in relation to models of short-term memory and the phenomenon of repetition blindness.

  12. Short-Term Volunteer Teachers in Rural China: Challenges and Needs

    ERIC Educational Resources Information Center

    Zhou, Huiquan; Shang, Xinyuan

    2011-01-01

    The brain-drain caused by imbalanced economic development has produced a lack of qualified teachers in rural China. Short-term volunteer teaching has emerged as a response. Despite the popularity of such programs, little systematic data have been gathered regarding their strengths and weaknesses. A short-term volunteer teaching program was…

  13. Short-term energy outlook, January 1999

    SciTech Connect

    1999-01-01

    The Energy Information Administration (EIA) prepares the Short-Term Energy Outlook (energy supply, demand, and price projections) monthly. The forecast period for this issue of the Outlook extends from January 1999 through December 2000. Data values for the fourth quarter 1998, however, are preliminary EIA estimates (for example, some monthly values for petroleum supply and disposition are derived in part from weekly data reported in EIA`s Weekly Petroleum Status Report) or are calculated from model simulations that use the latest exogenous information available (for example, electricity sales and generation are simulated by using actual weather data). The historical energy data, compiled in the January 1999 version of the Short-Term Integrated Forecasting System (STIFS) database, are mostly EIA data regularly published in the Monthly Energy Review, Petroleum Supply Monthly, and other EIA publications. Minor discrepancies between the data in these publications and the historical data in this Outlook are due to independent rounding. The STIFS model is driven principally by three sets of assumptions or inputs: estimates of key macroeconomic variables, world oil price assumptions, and assumptions about the severity of weather. Macroeconomic estimates are produced by DRI/McGraw-Hill but are adjusted by EIA to reflect EIA assumptions about the world price of crude oil, energy product prices, and other assumptions which may affect the macroeconomic outlook. By varying the assumptions, alternative cases are produced by using the STIFS model. 28 figs., 19 tabs.

  14. Short-term energy outlook, July 1998

    SciTech Connect

    1998-07-01

    The Energy Information Administration (EIA) prepares The Short-Term Energy Outlook (energy supply, demand, and price projections) monthly for distribution on the internet at: www.eia.doe.gov/emeu/steo/pub/contents.html. In addition, printed versions of the report are available to subscribers in January, April, July and October. The forecast period for this issue of the Outlook extends from July 1998 through December 1999. Values for second quarter of 1998 data, however, are preliminary EIA estimates (for example, some monthly values for petroleum supply and disposition are derived in part from weekly data reported in EIA`s Weekly Petroleum Status Report) or are calculated from model simulations that use the latest exogenous information available (for example, electricity sales and generation are simulated by using actual weather data). The historical energy data, compiled in the July 1998 version of the Short-Term Integrated Forecasting System (STIFS) database, are mostly EIA data regularly published in the Monthly Energy Review, Petroleum Supply Monthly, and other EIA publications. Minor discrepancies between the data in these publications and the historical data in this Outlook are due to independent rounding. 28 figs., 19 tabs.

  15. Short-term memory in zebrafish (Danio rerio).

    PubMed

    Jia, Jason; Fernandes, Yohaan; Gerlai, Robert

    2014-08-15

    Learning and memory represent perhaps the most complex behavioral phenomena. Although their underlying mechanisms have been extensively analyzed, only a fraction of the potential molecular components have been identified. The zebrafish has been proposed as a screening tool with which mechanisms of complex brain functions may be systematically uncovered. However, as a relative newcomer in behavioral neuroscience, the zebrafish has not been well characterized for its cognitive and mnemonic features, thus learning and/or memory screens with adults have not been feasible. Here we study short-term memory of adult zebrafish. We show animated images of conspecifics (the stimulus) to the experimental subject during 1 min intervals on ten occasions separated by different (2, 4, 8 or 16 min long) inter-stimulus intervals (ISI), a between subject experimental design. We quantify the distance of the subject from the image presentation screen during each stimulus presentation interval, during each of the 1-min post-stimulus intervals immediately following the stimulus presentations and during each of the 1-min intervals furthest away from the last stimulus presentation interval and just before the next interval (pre-stimulus interval), respectively. Our results demonstrate significant retention of short-term memory even in the longest ISI group but suggest no acquisition of reference memory. Because in the employed paradigm both stimulus presentation and behavioral response quantification is computer automated, we argue that high-throughput screening for drugs or mutations that alter short-term memory performance of adult zebrafish is now becoming feasible.

  16. Does tonality boost short-term memory in congenital amusia?

    PubMed

    Albouy, Philippe; Schulze, Katrin; Caclin, Anne; Tillmann, Barbara

    2013-11-06

    Congenital amusia is a neuro-developmental disorder of music perception and production. Recent findings have demonstrated that this deficit is linked to an impaired short-term memory for tone sequences. As it has been shown before that non-musicians' implicit knowledge of musical regularities can improve short-term memory for tone information, the present study investigated if this type of implicit knowledge could also influence amusics' short-term memory performance. Congenital amusics and their matched controls, who were non-musicians, had to indicate whether sequences of five tones, presented in pairs, were the same or different; half of the pairs respected musical regularities (tonal sequences) and the other half did not (atonal sequences). As previously reported for non-musician participants, the control participants showed better performance (as measured with d') for tonal sequences than for atonal ones. While this improvement was not observed in amusics, both control and amusic participants showed faster response times for tonal sequences than for atonal sequences. These findings suggest that some implicit processing of tonal structures is potentially preserved in congenital amusia. This observation is encouraging as it strengthens the perspective to exploit implicit knowledge to help reducing pitch perception and memory deficits in amusia.

  17. Comparison on Response and Dissolution Rates Between Ursodeoxycholic Acid Alone or in Combination With Chenodeoxycholic Acid for Gallstone Dissolution According to Stone Density on CT Scan

    PubMed Central

    Lee, Jae Min; Hyun, Jong Jin; Choi, In Young; Yeom, Suk Keu; Kim, Seung Young; Jung, Sung Woo; Jung, Young Kul; Koo, Ja Seol; Yim, Hyung Joon; Lee, Hong Sik; Lee, Sang Woo; Kim, Chang Duck

    2015-01-01

    Abstract Medical dissolution of gallstone is usually performed on radiolucent gallstones in a functioning gallbladder. However, absence of visible gallstone on plain abdominal x-ray does not always preclude calcification. This study aims to compare the response and dissolution rates between ursodeoxycholic acid (UDCA) alone or in combination with chenodeoxycholic acid (CDCA) according to stone density on computed tomography (CT) scan. A total of 126 patients underwent dissolution therapy with either UDCA alone or combination of CDCA and UDCA (CNU) from December 2010 to March 2014 at Korea University Ansan Hospital. In the end, 81 patients (CNU group = 44, UDCA group = 37) completed dissolution therapy for 6 months. Dissolution rate (percentage reduction in the gallstone volume) and response to therapy (complete dissolution or partial dissolution defined as reduction in stone volume of >50%) were compared between the 2 groups. Dissolution and response rates of sludge was also compared between the 2 groups. The overall response rate was 50.6% (CNU group 43.2% vs UDCA group 59.5%, P = 0.14), and the overall dissolution rate was 48.34% (CNU group 41.5% vs UDCA group 56.5%, P = 0.13). When analyzed according to stone density, response rate was 33.3%, 87.1%, 30.0%, and 6.2% for hypodense, isodense, hyperdense, and calcified stones, respectively. Response rate (85.7% vs 88.2%, P = 0.83) and dissolution rate (81.01% vs 85.38%, P = 0.17) of isodense stones were similar between CNU and UDCA group. When only sludge was considered, the overall response rate was 87.5% (CNU group 71.4% vs UDCA group 94.1%, P = 0.19), and the overall dissolution rate was 85.42% (CNU group 67.9% vs UDCA group 92.7%, P = 0.23). Patients with isodense gallstones and sludge showed much better response to dissolution therapy with CNU and UDCA showing comparable efficacy. Therefore, CT scan should be performed before medication therapy if stone dissolution is intended

  18. Vitreon, a short-term vitreoretinal tamponade.

    PubMed Central

    Blinder, K J; Peyman, G A; Desai, U R; Nelson, N C; Alturki, W; Paris, C L

    1992-01-01

    This investigation of the liquid perfluorocarbon, perfluorophenanthrene (Vitreon), establishes its safety and efficacy as a short-term vitreoretinal tamponade. We utilised Vitreon as an intraoperative tool and postoperative vitreoretinal tamponade in 16 patients. Proliferative vitreoretinopathy (PVR) (six), giant retinal tear (four), rhegmatogenous retinal detachment (three), retinal detachment with keratoprosthesis (two), and submacular and vitreous haemorrhage (one) were successfully repaired. Vitreon was left in the eye and removed 5 days to 4 weeks postoperatively. Complications encountered included proliferative PVR (five), limited peripheral retinal detachment (three), macular pucker (two) cataract (three), hypotony (two), excessive fibrin reaction (one), and elevated intraocular pressure (one). At the latest evaluation, all retinas are attached with a follow-up of 1.25 to 12 months (mean 6.8 months). PMID:1420054

  19. Economics of solar energy: Short term costing

    NASA Astrophysics Data System (ADS)

    Klee, H.

    The solar economics based on life cycle costs are refuted as both imaginary and irrelevant. It is argued that predicting rates of inflation and fuel escalation, expected life, maintenance costs, and legislation over the next ten to twenty years is pure guesswork. Furthermore, given the high mobility level of the U.S. population, the average consumer is skeptical of long run arguments which will pay returns only to the next owners. In the short term cost analysis, the house is sold prior to the end of the expected life of the system. The cash flow of the seller and buyer are considered. All the relevant factors, including the federal tax credit and the added value of the house because of the solar system are included.

  20. Marathon Running May Cause Short-Term Kidney Injury

    MedlinePlus

    ... page: https://medlineplus.gov/news/fullstory_164324.html Marathon Running May Cause Short-Term Kidney Injury But ... of endurance are also tough on the kidneys. "Marathon runners demonstrate transient or reverse short-term kidney ...

  1. 75 FR 24497 - Short-Term, Small Amount Loans

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-05

    ... ADMINISTRATION 12 CFR Part 701 RIN 3133-AD71 Short-Term, Small Amount Loans AGENCY: National Credit Union... federal credit unions (FCUs) to offer short-term, small amount loans (STS loans) as a viable alternative... regcomments@ncua.gov . Include ``[Your name] Comments on Notice of Proposed Rulemaking (Short-term,...

  2. Short-term energy outlook quarterly projections. First quarter 1994

    SciTech Connect

    Not Available

    1994-02-07

    The Energy Information Administration (EIA) prepares quarterly, short- term energy supply, demand, and price projections for publication in February, May, August, and November in the Short-Term Energy Outlook (Outlook). An annual supplement analyzes the performance of previous forecasts, compares recent cases with those of other forecasting services, and discusses current topics related to the short-term energy markets.

  3. In Search of Decay in Verbal Short-Term Memory

    ERIC Educational Resources Information Center

    Berman, Marc G.; Jonides, John; Lewis, Richard L.

    2009-01-01

    Is forgetting in the short term due to decay with the mere passage of time, interference from other memoranda, or both? Past research on short-term memory has revealed some evidence for decay and a plethora of evidence showing that short-term memory is worsened by interference. However, none of these studies has directly contrasted decay and…

  4. Short-term energy outlook, April 1999

    SciTech Connect

    1999-04-01

    The forecast period for this issue of the Outlook extends from April 1999 through December 2000. Data values for the first quarter 1999, however, are preliminary EIA estimates (for example, some monthly values for petroleum supply and disposition are derived in part from weekly data reported in EIA`s Weekly Petroleum Status Report) or are calculated from model simulations that use the latest exogenous information available (for example, electricity sales and generation are simulated by using actual weather data). The historical energy data, compiled in the April 1999 version of the Short-Term Integrated forecasting system (STIFS) database, are mostly EIA data regularly published in the Monthly Energy Review, Petroleum Supply Monthly, and other EIA publications. Minor discrepancies between the data in these publications and the historical data in this Outlook are due to independent rounding. The STIFS model is driven principally by three sets of assumptions or inputs: estimates of key macroeconomic variables, world oil price assumptions, and assumptions about the severity of weather. Macroeconomic estimates are produced by DRI/McGraw-Hill but are adjusted by EIA to reflect EIA assumptions about the world price of crude oil, energy product prices, and other assumptions which may affect the macroeconomic outlook. By varying the assumptions, alternative cases are produced by using the STIFS model. 25 figs., 19 tabs.

  5. Short-term GNSS satellite clock stability

    NASA Astrophysics Data System (ADS)

    Griggs, E.; Kursinski, E. R.; Akos, D.

    2015-08-01

    Global Navigation Satellite System (GNSS) clock stability is characterized via the modified Allan deviation using active hydrogen masers as the receiver frequency reference. The high stability of the maser reference allows the GNSS clock contribution to the GNSS carrier phase variance to be determined quite accurately. Satellite clock stability for four different GNSS constellations are presented, highlighting the similarities and differences between the constellations as well as satellite blocks and clock types. Impact on high-rate applications, such as GNSS radio occultation (RO), is assessed through the calculation of the maximum carrier phase error due to clock instability. White phase noise appears to dominate at subsecond time scales. However, while we derived the theoretical contribution of white phase modulation to the modified Allan deviation, our analysis of the GNSS satellite clocks was limited to 1-200 s time scales because of inconsistencies between the subsecond results from the commercial and software-defined receivers. The rubidium frequency standards on board the Global Positioning System (GPS) Block IIF, BeiDou, and Galileo satellites show improved stability results in comparison to previous GPS blocks for time scales relevant to RO. The Globalnaya Navigatsionnaya Sputnikovaya Sistema (GLONASS) satellites are the least stable of the GNSS constellations in the short term and will need high-rate corrections to produce RO results comparable to those from the other GNSS constellations.

  6. Continuity of Landsat observations: Short term considerations

    USGS Publications Warehouse

    Wulder, Michael A.; White, Joanne C.; Masek, Jeffery G.; Dwyer, John L.; Roy, David P.

    2011-01-01

    As of writing in mid-2010, both Landsat-5 and -7 continue to function, with sufficient fuel to enable data collection until the launch of the Landsat Data Continuity Mission (LDCM) scheduled for December of 2012. Failure of one or both of Landsat-5 or -7 may result in a lack of Landsat data for a period of time until the 2012 launch. Although the potential risk of a component failure increases the longer the sensor's design life is exceeded, the possible gap in Landsat data acquisition is reduced with each passing day and the risk of Landsat imagery being unavailable diminishes for all except a handful of applications that are particularly data demanding. Advances in Landsat data compositing and fusion are providing opportunities to address issues associated with Landsat-7 SLC-off imagery and to mitigate a potential acquisition gap through the integration of imagery from different sensors. The latter will likely also provide short-term, regional solutions to application-specific needs for the continuity of Landsat-like observations. Our goal in this communication is not to minimize the community's concerns regarding a gap in Landsat observations, but rather to clarify how the current situation has evolved and provide an up-to-date understanding of the circumstances, implications, and mitigation options related to a potential gap in the Landsat data record.

  7. Gaze direction affects visuo-spatial short-term memory.

    PubMed

    Carlei, Christophe; Kerzel, Dirk

    2014-10-01

    Hemispheric asymmetries were investigated by changing the horizontal position of stimuli that had to be remembered in a visuo-spatial short-term memory task. Observers looked at matrices containing a variable number of filled squares on the left or right side of the screen center. At stimulus offset, participants reproduced the positions of the filled squares in an empty response matrix. Stimulus and response matrices were presented in the same quadrant. We observed that memory performance was better when the matrices were shown on the left side of the screen. We distinguished between recall strategies that relied on visual or non-visual (verbal) cues and found that the effect of gaze position occurred more reliably in participants using visual recall strategies. Overall, the results show that there is a solid enhancement of visuo-spatial short-term memory when observers look to the left. In contrast, vertical position had no influence on performance. We suggest that unilateral gaze to the left activates centers in the right hemisphere contributing to visuo-spatial memory.

  8. Short-term energy outlook. Quarterly projections, Third quarter 1994

    SciTech Connect

    Not Available

    1994-08-02

    The Energy Information Administration (EIA) prepares quarterly, short-term energy supply, demand, and price projections for publication in February, May, August, and November in the Short-Term Energy Outlook (Outlook). An annual supplement analyzes the performance of previous forecasts, compares recent cases with those of other forecasting services, and discusses current topics related to the short-term energy markets. (See Short-Term Energy Outlook Annual Supplement, DOE/EIA-0202). The feature article for this issue is Demand, Supply and Price Outlook for Reformulated Gasoline, 1995.

  9. Short-Term Memory and Aphasia: From Theory to Treatment.

    PubMed

    Minkina, Irene; Rosenberg, Samantha; Kalinyak-Fliszar, Michelene; Martin, Nadine

    2017-02-01

    This article reviews existing research on the interactions between verbal short-term memory and language processing impairments in aphasia. Theoretical models of short-term memory are reviewed, starting with a model assuming a separation between short-term memory and language, and progressing to models that view verbal short-term memory as a cognitive requirement of language processing. The review highlights a verbal short-term memory model derived from an interactive activation model of word retrieval. This model holds that verbal short-term memory encompasses the temporary activation of linguistic knowledge (e.g., semantic, lexical, and phonological features) during language production and comprehension tasks. Empirical evidence supporting this model, which views short-term memory in the context of the processes it subserves, is outlined. Studies that use a classic measure of verbal short-term memory (i.e., number of words/digits correctly recalled in immediate serial recall) as well as those that use more intricate measures (e.g., serial position effects in immediate serial recall) are discussed. Treatment research that uses verbal short-term memory tasks in an attempt to improve language processing is then summarized, with a particular focus on word retrieval. A discussion of the limitations of current research and possible future directions concludes the review.

  10. Biochemical and hematologic changes after short-term space flight

    NASA Technical Reports Server (NTRS)

    Leach, Carolyn S.

    1991-01-01

    Clinical laboratory data from blood samples obtained from astronauts before and after 28 flights (average duration = 6 days) of the Space Shuttle were analyzed by the paired t-test and the Wilcoxon signed-rank test and compared with data from the Skylab flights (duration = 28, 56, and 84 days). Angiotensin I and aldosterone were elevated immediately after short-term space flights, but the response of angiotensin I was delayed after Skylab flights. Serum calcium was not elevated after Shuttle flights, but magnesium and uric acid decreased after both Shuttle and Skylab. Creatine phosphokinase in serum was reduced after Shuttle but not Skylab flights, probably because exercises to prevent deconditioning were not performed on the Shuttle. Total cholesterol was unchanged after Shuttle flights, but low density lipoprotein cholesterol increased and high density lipoprotein cholesterol decreased. The concentration of red blood cells was elevated after Shuttle flights and reduced after Skylab flights.

  11. 75 FR 58285 - Short-Term, Small Amount Loans

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-24

    ... Part 701 RIN 3133-AD71 Short-Term, Small Amount Loans Agency: National Credit Union Administration... unions (FCUs) to offer short-term, small amount loans (STS loans) as a viable alternative to predatory... permitted under the general lending rule, but imposes limitations on the permissible term, amount, and...

  12. 77 FR 21057 - Short-Term Investment Funds

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-09

    ... limiting the STIF's investments to shorter-term assets and generally requiring those assets to be held to... to invest the STIF's fiduciary assets in a diversified portfolio of short- term, high quality debt... Office of the Comptroller of the Currency 12 CFR Part 9 RIN 1557-AD37 Short-Term Investment Funds...

  13. Short-term energy outlook, annual supplement 1994

    SciTech Connect

    Not Available

    1994-08-01

    The Short-Term Energy Outlook Annual Supplement (Supplement) is published once a year as a complement to the Short-Term Energy Outlook (Outlook), Quarterly Projections. The purpose of the Supplement is to review the accuracy of the forecasts published in the Outlook, make comparisons with other independent energy forecasts, and examine current energy topics that affect the forecasts.

  14. Short-Term Reciprocity in Late Parent-Child Relationships

    ERIC Educational Resources Information Center

    Leopold, Thomas; Raab, Marcel

    2011-01-01

    Long-term concepts of parent-child reciprocity assume that the amount of support given and received is only balanced in a generalized fashion over the life course. We argue that reciprocity in parent-child relationships also operates in the short term. Our analysis of short-term reciprocity focuses on concurrent exchange in its main upward and…

  15. A Short-Term Delivery Model for Counseling Services.

    ERIC Educational Resources Information Center

    Knott, J. Eugene

    The author discusses a short-term delivery model which forms the essential mode of operation at the counseling center at Rhode Island College. He prefaces his discription of the model by indicating that not all clients, problems or counselors are amenable to this short-term approach. There are three steps or elements in the delivery model: 1)…

  16. Short-Term Training--Where the Action Is!

    ERIC Educational Resources Information Center

    Moore, George R.

    In order to address major permanent changes in the economic structure and workforce of its community, Chemeketa Community College (CCC) in Oregon has made a commitment to initiate as many short-term training programs as its resources permit. Short-term training, which takes less time than regular one-year certificate or two-year associate degree…

  17. Double Dissociations in Visual and Spatial Short-Term Memory

    ERIC Educational Resources Information Center

    Klauer, Karl Christoph; Zhao, Zengmei

    2004-01-01

    A visual short-term memory task was more strongly disrupted by visual than spatial interference, and a spatial memory task was simultaneously more strongly disrupted by spatial than visual interference. This double dissociation supports a fractionation of visuospatial short-term memory into separate visual and spatial components. In 6 experiments,…

  18. Auditory short-term memory in the primate auditory cortex.

    PubMed

    Scott, Brian H; Mishkin, Mortimer

    2016-06-01

    Sounds are fleeting, and assembling the sequence of inputs at the ear into a coherent percept requires auditory memory across various time scales. Auditory short-term memory comprises at least two components: an active ׳working memory' bolstered by rehearsal, and a sensory trace that may be passively retained. Working memory relies on representations recalled from long-term memory, and their rehearsal may require phonological mechanisms unique to humans. The sensory component, passive short-term memory (pSTM), is tractable to study in nonhuman primates, whose brain architecture and behavioral repertoire are comparable to our own. This review discusses recent advances in the behavioral and neurophysiological study of auditory memory with a focus on single-unit recordings from macaque monkeys performing delayed-match-to-sample (DMS) tasks. Monkeys appear to employ pSTM to solve these tasks, as evidenced by the impact of interfering stimuli on memory performance. In several regards, pSTM in monkeys resembles pitch memory in humans, and may engage similar neural mechanisms. Neural correlates of DMS performance have been observed throughout the auditory and prefrontal cortex, defining a network of areas supporting auditory STM with parallels to that supporting visual STM. These correlates include persistent neural firing, or a suppression of firing, during the delay period of the memory task, as well as suppression or (less commonly) enhancement of sensory responses when a sound is repeated as a ׳match' stimulus. Auditory STM is supported by a distributed temporo-frontal network in which sensitivity to stimulus history is an intrinsic feature of auditory processing. This article is part of a Special Issue entitled SI: Auditory working memory.

  19. Verbal Short-Term Memory Span in Speech-Disordered Children: Implications for Articulatory Coding in Short-Term Memory.

    ERIC Educational Resources Information Center

    Raine, Adrian; And Others

    1991-01-01

    Children with speech disorders had lower short-term memory capacity and smaller word length effect than control children. Children with speech disorders also had reduced speech-motor activity during rehearsal. Results suggest that speech rate may be a causal determinant of verbal short-term memory capacity. (BC)

  20. Analog VLSI Circuits for Short-Term Dynamic Synapses

    NASA Astrophysics Data System (ADS)

    Liu, Shih-Chii

    2003-12-01

    Short-term dynamical synapses increase the computational power of neuronal networks. These synapses act as additional filters to the inputs of a neuron before the subsequent integration of these signals at its cell body. In this work, we describe a model of depressing and facilitating synapses derived from a hardware circuit implementation. This model is equivalent to theoretical models of short-term synaptic dynamics in network simulations. These circuits have been added to a network of leaky integrate-and-fire neurons. A cortical model of direction-selectivity that uses short-term dynamic synapses has been implemented with this network.

  1. Short-term energy outlook. Quarterly projections, Third quarter 1995

    SciTech Connect

    1995-08-02

    The Energy Information Administration (EIA) prepares quarterly, short-term energy supply, demand, and price projections for publication in February, May, August, and November in the Short-Term Energy Outlook (Outlook). An annual supplement analyzes the performance of previous forecasts, compares recent projections with those of other forecasting services, and discusses current topics related to the short-term energy markets. The forecast period for this issue of the Outlook extends from the third quarter of 1995 through the fourth quarter of 1996. Values for the second quarter of 1995, however, are preliminary EIA estimates.

  2. Therapist Interventions in Short-Term Dynamic Psychotherapy: Six Expert Treatments

    ERIC Educational Resources Information Center

    Town, Joel Michael; McCullough, Leigh; Hardy, Gillian E.

    2012-01-01

    This paper describes the profile of verbal response modes utilised in the expert application of Short-Term Dynamic Psychotherapy (STDP). One hundred and fifteen randomly selected segments from six treatments of STDP were analysed. Trained raters used a verbal response mode coding system to examine the individual speaking turns of an expert…

  3. Speech generating devices and modality of short-term word storage.

    PubMed

    Dukhovny, Elena; Soto, Gloria

    2013-09-01

    Persons with severe speech impairments frequently communicate via non-speech means, such as speech-generating devices (SGDs). In studies of people without disabilities, use of non-speech responses has activated non-phonological modalities for short-term word storage. In the current study, short-term word storage was evaluated in 23 pre-trained adult speakers without disabilities and in four individuals who use SGDs for communication. Results indicated that participants without disabilities stored lists of words phonologically when using SGDs. Individuals who used SGDs were most successful in recall of high- frequency words, with preliminary evidence of phonological encoding for short-term storage in preparation for non-speech responses. Further research is needed to describe possible concurrent storage modalities.

  4. A Postsynaptic Role for Short-Term Neuronal Facilitation in Dendritic Spines

    PubMed Central

    Yang, Sunggu; Santos, Mariton D.; Tang, Cha-Min; Kim, Jae Geun; Yang, Sungchil

    2016-01-01

    Synaptic plasticity is a fundamental component of information processing in the brain. Presynaptic facilitation in response to repetitive stimuli, often referred to as paired-pulse facilitation (PPF), is a dominant form of short-term synaptic plasticity. Recently, an additional cellular mechanism for short-term facilitation, short-term postsynaptic plasticity (STPP), has been proposed. While a dendritic mechanism was described in hippocampus, its expression has not yet been demonstrated at the levels of the spine. Furthermore, it is unknown whether the mechanism can be expressed in other brain regions, such as sensory cortex. Here, we demonstrated that a postsynaptic response can be facilitated by prior spine excitation in both hippocampal and cortical neurons, using 3D digital holography and two-photon calcium imaging. The coordinated action of pre- and post-synaptic plasticity may provide a more thorough account of information processing in the brain. PMID:27746721

  5. Retrieval-Induced Inhibition in Short-Term Memory.

    PubMed

    Kang, Min-Suk; Choi, Joongrul

    2015-07-01

    We used a visual illusion called motion repulsion as a model system for investigating competition between two mental representations. Subjects were asked to remember two random-dot-motion displays presented in sequence and then to report the motion directions for each. Remembered motion directions were shifted away from the actual motion directions, an effect similar to the motion repulsion observed during perception. More important, the item retrieved second showed greater repulsion than the item retrieved first. This suggests that earlier retrieval exerted greater inhibition on the other item being held in short-term memory. This retrieval-induced motion repulsion could be explained neither by reduced cognitive resources for maintaining short-term memory nor by continued inhibition between short-term memory representations. These results indicate that retrieval of memory representations inhibits other representations in short-term memory. We discuss mechanisms of retrieval-induced inhibition and their implications for the structure of memory.

  6. 22 CFR 62.21 - Short-term scholars.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Program Provisions § 62.21 Short-term scholars. (a) Introduction. These regulations govern scholars coming... programs, confer on common problems and projects, and promote professional relationships and communications... lecturing, observing, consulting, training, or demonstrating special skills at research...

  7. Regional Short-Term Energy Model (RSTEM) Overview

    EIA Publications

    2009-01-01

    The Regional Short-Term Energy Model (RSTEM) utilizes estimated econometric relationships for demand, inventories and prices to forecast energy market outcomes across key sectors and selected regions throughout the United States.

  8. Encephalopathy and vestibulopathy following short-term hydrocarbon exposure

    SciTech Connect

    Hodgson, M.J.; Furman, J.; Ryan, C.; Durrant, J.; Kern, E.

    1989-01-01

    Dizziness, headaches, and weakness occurred among three men after short-term hydrocarbon exposure during improper welding procedures in a closed container. Symptoms were related to objective evidence of vestibular and cognitive dysfunction. Symptoms and abnormal test results persisted for 6 to 18 months. Simulation of the accident failed to demonstrate likely exposures except aliphatic hydrocarbons, well within the permissible exposure levels. Short-term exposures to neurotoxins may lead to long-term central nervous system abnormalities.

  9. In Search of Decay in Verbal Short-Term Memory

    PubMed Central

    Berman, Marc G.; Jonides, John; Lewis, Richard L.

    2014-01-01

    Is forgetting in the short term due to decay with the mere passage of time, interference from other memoranda, or both? Past research on short-term memory has revealed some evidence for decay and a plethora of evidence showing that short-term memory is worsened by interference. However, none of these studies has directly contrasted decay and interference in short-term memory in a task that rules out the use of rehearsal processes. In this article the authors present a series of studies using a novel paradigm to address this problem directly, by interrogating the operation of decay and interference in short-term memory without rehearsal confounds. The results of these studies indicate that short-term memories are subject to very small decay effects with the mere passage of time but that interference plays a much larger role in their degradation. The authors discuss the implications of these results for existing models of memory decay and interference. PMID:19271849

  10. Short-term memory and dual task performance

    NASA Technical Reports Server (NTRS)

    Regan, J. E.

    1982-01-01

    Two hypotheses concerning the way in which short-term memory interacts with another task in a dual task situation are considered. It is noted that when two tasks are combined, the activity of controlling and organizing performance on both tasks simultaneously may compete with either task for a resource; this resource may be space in a central mechanism or general processing capacity or it may be some task-specific resource. If a special relationship exists between short-term memory and control, especially if there is an identity relationship between short-term and a central controlling mechanism, then short-term memory performance should show a decrement in a dual task situation. Even if short-term memory does not have any particular identity with a controlling mechanism, but both tasks draw on some common resource or resources, then a tradeoff between the two tasks in allocating resources is possible and could be reflected in performance. The persistent concurrence cost in memory performance in these experiments suggests that short-term memory may have a unique status in the information processing system.

  11. Effect of Macronutrient Composition on Short-Term Food Intake and Weight Loss12

    PubMed Central

    Bellissimo, Nick; Akhavan, Tina

    2015-01-01

    The purpose of this review is to describe the role of macronutrient composition on the suppression of short-term food intake (FI) and weight loss. The effects of macronutrient composition on short-term FI will be reviewed first, followed by a brief examination of longer-term clinical trials that vary in effects of dietary macronutrient composition on weight loss. The objectives were: 1) to examine the effect of macronutrient composition on the suppression of short-term FI, 2) to determine whether some macronutrient sources suppress FI beyond their provision of energy, 3) to assess the combined effects of macronutrients on FI and glycemic response, and 4) to determine whether knowledge of the effect of macronutrients on short-term FI has led to greater success in spontaneous weight loss, adherence to energy-restricted diets, and better weight maintenance after weight loss. Although knowledge of macronutrient composition on short-term FI regulation has advanced our understanding of the role of diet composition on energy balance, it has yet to lead to greater success in long-term weight loss and weight maintenance. It is clear from this review that many approaches based on manipulating dietary macronutrient composition can help people lose weight as long as they follow the diets. However, only by evaluating the interaction between the physiologic systems that govern FI and body weight may the benefits of dietary macronutrient composition be fully realized. PMID:25979503

  12. Quantification of the pathological response and fate in the lung and pleura of chrysotile in combination with fine particles compared to amosite-asbestos following short-term inhalation exposure.

    PubMed

    Bernstein, D M; Rogers, R A; Sepulveda, R; Donaldson, K; Schuler, D; Gaering, S; Kunzendorf, P; Chevalier, J; Holm, S E

    2011-06-01

    The marked difference in biopersistence and pathological response between chrysotile and amphibole asbestos has been well documented. This study is unique in that it has examined a commercial chrysotile product that was used as a joint compound. The pathological response was quantified in the lung and translocation of fibers to and pathological response in the pleural cavity determined. This paper presents the final results from the study. Rats were exposed by inhalation 6 h/day for 5 days to a well-defined fiber aerosol. Subgroups were examined through 1 year. The translocation to and pathological response in the pleura was examined by scanning electron microscopy and confocal microscopy (CM) using noninvasive methods. The number and size of fibers was quantified using transmission electron microscopy and CM. This is the first study to use such techniques to characterize fiber translocation to and the response of the pleural cavity. Amosite fibers were found to remain partly or fully imbedded in the interstitial space through 1 year and quickly produced granulomas (0 days) and interstitial fibrosis (28 days). Amosite fibers were observed penetrating the visceral pleural wall and were found on the parietal pleural within 7 days postexposure with a concomitant inflammatory response seen by 14 days. Pleural fibrin deposition, fibrosis, and adhesions were observed, similar to that reported in humans in response to amphibole asbestos. No cellular or inflammatory response was observed in the lung or the pleural cavity in response to the chrysotile and sanded particles (CSP) exposure. These results provide confirmation of the important differences between CSP and amphibole asbestos.

  13. Quantification of the pathological response and fate in the lung and pleura of chrysotile in combination with fine particles compared to amosite-asbestos following short-term inhalation exposure

    PubMed Central

    Bernstein, DM; Rogers, RA; Sepulveda, R; Donaldson, K; Schuler, D; Gaering, S; Kunzendorf, P; Chevalier, J; Holm, SE

    2011-01-01

    The marked difference in biopersistence and pathological response between chrysotile and amphibole asbestos has been well documented. This study is unique in that it has examined a commercial chrysotile product that was used as a joint compound. The pathological response was quantified in the lung and translocation of fibers to and pathological response in the pleural cavity determined. This paper presents the final results from the study. Rats were exposed by inhalation 6 h/day for 5 days to a well-defined fiber aerosol. Subgroups were examined through 1 year. The translocation to and pathological response in the pleura was examined by scanning electron microscopy and confocal microscopy (CM) using noninvasive methods.The number and size of fibers was quantified using transmission electron microscopy and CM. This is the first study to use such techniques to characterize fiber translocation to and the response of the pleural cavity. Amosite fibers were found to remain partly or fully imbedded in the interstitial space through 1 year and quickly produced granulomas (0 days) and interstitial fibrosis (28 days). Amosite fibers were observed penetrating the visceral pleural wall and were found on the parietal pleural within 7 days postexposure with a concomitant inflammatory response seen by 14 days. Pleural fibrin deposition, fibrosis, and adhesions were observed, similar to that reported in humans in response to amphibole asbestos. No cellular or inflammatory response was observed in the lung or the pleural cavity in response to the chrysotile and sanded particles (CSP) exposure. These results provide confirmation of the important differences between CSP and amphibole asbestos. PMID:21639706

  14. Short-term memory predictions across the lifespan: monitoring span before and after conducting a task.

    PubMed

    Bertrand, Julie Marilyne; Moulin, Chris John Anthony; Souchay, Céline

    2016-06-17

    Our objective was to explore metamemory in short-term memory across the lifespan. Five age groups participated in this study: 3 groups of children (4-13 years old), and younger and older adults. We used a three-phase task: prediction-span-postdiction. For prediction and postdiction phases, participants reported with a Yes/No response if they could recall in order a series of images. For the span task, they had to actually recall such series. From 4 years old, children have some ability to monitor their short-term memory and are able to adjust their prediction after experiencing the task. However, accuracy still improves significantly until adolescence. Although the older adults had a lower span, they were as accurate as young adults in their evaluation, suggesting that metamemory is unimpaired for short-term memory tasks in older adults.

  15. Do nonlinearities play a significant role in short term, beat-to-beat variability?

    NASA Technical Reports Server (NTRS)

    Choi, H. G.; Mukkamala, R.; Moody, G. B.; Mark, R. G.

    2001-01-01

    Numerous studies of short-term beat-to-beat variability in cardiovascular signals have not resolved the debate about the completeness of linear analysis techniques. This aim of this paper is to evaluate further the role of nonlinearities in short-term, beat-to-beat variability. We compared linear autoregressive moving average (ARMA) and nonlinear neural network (NN) models for predicting instantaneous heart rate (HR) and mean arterial blood pressure (BP) from past HR and BP. To evaluate these models, we used HR and BP time series from the MIMIC database. Experimental results indicate that NN-based nonlinearities do not play a significant role and suggest that ARMA linear analysis techniques provide adequate characterization of the system dynamics responsible for generating short-term, beat-to-beat variability.

  16. Biochemical and hematologic changes after short-term space flight

    NASA Technical Reports Server (NTRS)

    Leach, C. S.

    1992-01-01

    Clinical laboratory data from blood samples obtained from astronauts before and after 28 flights (average duration = 6 days) of the Space Shuttle were analyzed by the paired t-test and the Wilcoxon signed-rank test and compared with data from the Skylab flights (duration approximately 28, 59, and 84 days). Angiotensin I and aldosterone were elevated immediately after short-term space flights, but the response of angiotensin I was delayed after Skylab flights. Serum calcium was not elevated after Shuttle flights, but magnesium and uric acid decreased after both Shuttle and Skylab. Creatine phosphokinase in serum was reduced after Shuttle but not Skylab flights, probably because exercises to prevent deconditioning were not performed on the Shuttle. Total cholesterol was unchanged after Shuttle flights, but low density lipoprotein cholesterol increased and high density lipoprotein cholesterol decreased. The concentration of red blood cells was elevated after Shuttle flights and reduced after Skylab flights. Reticulocyte count was decreased after both short- and long-term flights, indicating that a reduction in red blood cell mass is probably more closely related to suppression of red cell production than to an increase in destruction of erythrocytes. Serum ferritin and number of platelets were also elevated after Shuttle flights. In determining the reasons for postflight differences between the shorter and longer flights, it is important to consider not only duration but also countermeasures, differences between spacecraft, and procedures for landing and egress.

  17. Periodization of Carbohydrate Intake: Short-Term Effect on Performance

    PubMed Central

    Marquet, Laurie-Anne; Hausswirth, Christophe; Molle, Odeline; Hawley, John A.; Burke, Louise M.; Tiollier, Eve; Brisswalter, Jeanick

    2016-01-01

    Background: “Sleep-low” consists of a sequential periodization of carbohydrate (CHO) availability—low glycogen recovery after “train high” glycogen-depleting interval training, followed by an overnight-fast and light intensity training (“train low”) the following day. This strategy leads to an upregulation of several exercise-responsive signaling proteins, but the chronic effect on performance has received less attention. We investigated the effects of short-term exposure to this strategy on endurance performance. Methods: Following training familiarization, 11 trained cyclists were divided into two groups for a one-week intervention—one group implemented three cycles of periodized CHO intake to achieve the sleep-low strategy over six training sessions (SL, CHO intake: 6 g·kg−1·day−1), whereas the control group consumed an even distribution of CHO over the day (CON). Tests were a 2 h submaximal ride and a 20 km time trial. Results: SL improved their performance (mean: +3.2%; p < 0.05) compared to CON. The improvement was associated with a change in pacing strategy with higher power output during the second part of the test. No change in substrate utilization was observed after the training period for either group. Conclusion: Implementing the “sleep-low” strategy for one week improved performance by the same magnitude previously seen in a three-week intervention, without any significant changes in selected markers of metabolism. PMID:27897989

  18. Short-term fasting induces profound neuronal autophagy

    PubMed Central

    Flynn, Claudia T.; Wood, Malcolm R.; Kiosses, William B.

    2010-01-01

    Disruption of autophagy—a key homeostatic process in which cytosolic components are degraded and recycled through lysosomes—can cause neurodegeneration in tissue culture and in vivo. Upregulation of this pathway may be neuroprotective, and much effort is being invested in developing drugs that cross the blood brain barrier and increase neuronal autophagy. One well-recognized way of inducing autophagy is by food restriction, which upregulates autophagy in many organs including the liver; but current dogma holds that the brain escapes this effect, perhaps because it is a metabolically privileged site. Here, we have re-evaluated this tenet using a novel approach that allows us to detect, enumerate and characterize autophagosomes in vivo. We first validate the approach by showing that it allows the identification and characterization of autophagosomes in the livers of food-restricted mice. We use the method to identify constitutive autophagosomes in cortical neurons and Purkinje cells, and we show that short-term fasting leads to a dramatic upregulation in neuronal autophagy. The increased neuronal autophagy is revealed by changes in autophagosome abundance and characteristics, and by diminished neuronal mTOR activity in vivo, demonstrated by a reduction in levels of phosphorylated S6 ribosomal protein in Purkinje cells. The increased abundance of autophagosomes in Purkinje cells was confirmed using transmission electron microscopy. Our data lead us to speculate that sporadic fasting might represent a simple, safe and inexpensive means to promote this potentially therapeutic neuronal response. PMID:20534972

  19. Diverse thalamocortical short-term plasticity elicited by ongoing stimulation.

    PubMed

    Díaz-Quesada, Marta; Martini, Francisco J; Ferrati, Giovanni; Bureau, Ingrid; Maravall, Miguel

    2014-01-08

    To produce sensation, neuronal pathways must transmit and process stimulus patterns that unfold over time. This behavior is determined by short-term synaptic plasticity (STP), which shapes the temporal filtering properties of synapses in a pathway. We explored STP variability across thalamocortical (TC) synapses, measuring whole-cell responses to stimulation of TC fibers in layer 4 neurons of mouse barrel cortex in vitro. As expected, STP during stimulation from rest was dominated by depression. However, STP during ongoing stimulation was strikingly diverse across TC connections. Diversity took the form of variable tuning to the latest interstimulus interval: some connections responded weakly to shorter intervals, while other connections were facilitated. These behaviors did not cluster into categories but formed a continuum. Diverse tuning did not require disynaptic inhibition. Hence, monosynaptic excitatory lemniscal TC connections onto layer 4 do not behave uniformly during ongoing stimulation. Each connection responds differentially to particular stimulation intervals, enriching the ability of the pathway to convey complex, temporally fluctuating information.

  20. Leukocyte subsets and neutrophil function after short-term spaceflight

    NASA Technical Reports Server (NTRS)

    Stowe, R. P.; Sams, C. F.; Mehta, S. K.; Kaur, I.; Jones, M. L.; Feeback, D. L.; Pierson, D. L.

    1999-01-01

    Changes in leukocyte subpopulations and function after spaceflight have been observed but the mechanisms underlying these changes are not well defined. This study investigated the effects of short-term spaceflight (8-15 days) on circulating leukocyte subsets, stress hormones, immunoglobulin levels, and neutrophil function. At landing, a 1.5-fold increase in neutrophils was observed compared with preflight values; lymphocytes were slightly decreased, whereas the results were variable for monocytes. No significant changes were observed in plasma levels of immunoglobulins, cortisol, or adrenocorticotropic hormone. In contrast, urinary epinephrine, norepinephrine, and cortisol were significantly elevated at landing. Band neutrophils were observed in 9 of 16 astronauts. Neutrophil chemotactic assays showed a 10-fold decrease in the optimal dose response after landing. Neutrophil adhesion to endothelial cells was increased both before and after spaceflight. At landing, the expression of MAC-1 was significantly decreased while L-selectin was significantly increased. These functional alterations may be of clinical significance on long-duration space missions.

  1. The pathological response and fate in the lung and pleura of chrysotile in combination with fine particles compared to amosite asbestos following short-term inhalation exposure: interim results.

    PubMed

    Bernstein, D M; Rogers, R A; Sepulveda, R; Donaldson, K; Schuler, D; Gaering, S; Kunzendorf, P; Chevalier, J; Holm, S E

    2010-09-01

    The pathological response and translocation of a commercial chrysotile product similar to that which was used through the mid-1970s in a joint compound intended for sealing the interface between adjacent wall boards was evaluated in comparison to amosite asbestos. This study was unique in that it presents a combined real-world exposure and was the first study to investigate whether there were differences between chrysotile and amosite asbestos fibers in time course, size distribution, and pathological response in the pleural cavity. Rats were exposed by inhalation 6 h/day for 5 days to either sanded joint compound consisting of both chrysotile fibers and sanded joint compound particles (CSP) or amosite asbestos. Subgroups were examined through 1-year postexposure. No pathological response was observed at any time point in the CSP-exposure group. The long chrysotile fibers (L > 20 microm) cleared rapidly (T(1/2) of 4.5 days) and were not observed in the pleural cavity. In contrast, a rapid inflammatory response occurred in the lung following exposure to amosite resulting in Wagner grade 4 interstitial fibrosis within 28 days. Long amosite fibers had a T(1/2) > 1000 days and were observed in the pleural cavity within 7 days postexposure. By 90 days the long amosite fibers were associated with a marked inflammatory response on the parietal pleural. This study provides support that CSP following inhalation would not initiate an inflammatory response in the lung, and that the chrysotile fibers present do not migrate to, or cause an inflammatory response in the pleural cavity, the site of mesothelioma formation.

  2. Assessment of the short-term toxicity of TiO2 nanofiber in Sprague Dawley rats.

    PubMed

    Gato, Worlanyo E; Hunter, Daniel A; Byrd, Ian C; Mays, Christopher A; Yau, Wilson; Wu, Ji

    2017-02-09

    Synthetic nanomaterials have many unique chemical and physical properties, mainly due to their high specific surface area and quantum confinement effect. Specifically, titanium dioxide (TiO2 ) nanomaterial has high stability, anticorrosive, and photocatalytic properties. However, there are concerns over adverse biological effects resulting from bioeffects. This study was to investigate adverse effects associated with acute ingestion of TiO2 nanofiber (TDNF). TDNF was fabricated via electrospinning method, followed by dissolution in water. Six- to seven-week-old male Sprague Dawley rats were exposed to a total of 0, 40, and 60 ppm of TDNF for 2 weeks via oral gavage. Serum total protein and weight gain during the course of this study displayed marginal concentration-dependent alterations. These findings were followed by a global gene expression analysis to identify which transcripts might be responsive to TNDF toxicity. Differentially expressed mRNA levels were dose-dependently higher in animals exposed to TNDF. The majority of the affected genes were biochemically involved in immune response and inflammation. We believe this is due to the fact that TNDF is unable to penetrate the cell and forms phagocytosis sites that trigger inflammatory and immune response. All results taken together, short-term ingestion of TNDF produced marginal effects indicative of inflammation. Finally, the broad gene expression data were validated through quantification of immunoglobulin heavy chain alpha (Igha). Igha gene was upregulated in treated groups, showing similar expression patterns to the global gene expression data.

  3. Nordic Experiences: Participants' Expectations and Experiences of Short-Term Study Abroad Programs

    ERIC Educational Resources Information Center

    Rahikainen, Katariina; Hakkarainen, Kai

    2013-01-01

    The purpose of this study was to investigate Finnish high school students' and teachers' perceptions of the effects of short-term Nordic study abroad programs in which they had participated. The data presented were based on a "mixed-methods strategy." The data set consisted of responses from 158 students and 92 teachers to a specifically…

  4. Language repetition and short-term memory: an integrative framework

    PubMed Central

    Majerus, Steve

    2013-01-01

    Short-term maintenance of verbal information is a core factor of language repetition, especially when reproducing multiple or unfamiliar stimuli. Many models of language processing locate the verbal short-term maintenance function in the left posterior superior temporo-parietal area and its connections with the inferior frontal gyrus. However, research in the field of short-term memory has implicated bilateral fronto-parietal networks, involved in attention and serial order processing, as being critical for the maintenance and reproduction of verbal sequences. We present here an integrative framework aimed at bridging research in the language processing and short-term memory fields. This framework considers verbal short-term maintenance as an emergent function resulting from synchronized and integrated activation in dorsal and ventral language processing networks as well as fronto-parietal attention and serial order processing networks. To-be-maintained item representations are temporarily activated in the dorsal and ventral language processing networks, novel phoneme and word serial order information is proposed to be maintained via a right fronto-parietal serial order processing network, and activation in these different networks is proposed to be coordinated and maintained via a left fronto-parietal attention processing network. This framework provides new perspectives for our understanding of information maintenance at the non-word-, word- and sentence-level as well as of verbal maintenance deficits in case of brain injury. PMID:23874280

  5. Short-term energy outlook: Quarterly projections. Second quarter 1995

    SciTech Connect

    1995-05-02

    The Energy Information Administration (EIA) prepares quarterly, short-term energy supply, demand, and price projections for publication in February, May, August, and November in the Short-Term Energy Outlook (Outlook). An annual supplement analyzes the performance of previous forecasts, compares recent projections with those of other forecasting services, and discusses current topics related to the short-term energy markets. (See Short-Term Energy Outlook Annual Supplement, DOE/EIA-0202.) The forecast period for this issue of the Outlook extends from the second quarter of 1995 through the fourth quarter of 1996. Values for the first quarter of 1995, however, are preliminary EIA estimates (for example, some monthly values for petroleum supply and disposition are derived in part from weekly data reported in the Weekly Petroleum Status Report) or are calculated from model simulations using the latest exogenous information available (for example, electricity sales and generation are simulated using actual weather data). The historical energy data, compiled into the second quarter 1995 version of the Short-Term Integrated Forecasting System (STIFS) database, are mostly EIA data regularly published in the Monthly Energy Review, Petroleum Supply Monthly, and other EIA publications. Minor discrepancies between the data in these publications and the historical data in this Outlook are due to independent rounding. The STIFS database is archived quarterly and is available from the National Technical Information Service.

  6. Asymmetric features of short-term blood pressure variability.

    PubMed

    Guzik, Przemyslaw; Piskorski, Jaroslaw; Krauze, Tomasz; Narkiewicz, Krzysztof; Wykretowicz, Andrzej; Wysocki, Henryk

    2010-11-01

    Prolongations of cardiac cycles have a significantly larger contribution to short-term heart rate variability than shortenings--this is called heart rate asymmetry. Our aim is to establish the existence of blood pressure asymmetry phenomenon, which has not been done so far. We used 30-min resting continuous recordings of finger pressure waveforms from 227 healthy young volunteers (19-31 years old; 97 female), and performed Poincaré plot analysis of systolic blood pressure (SBP) to quantify the effect. Median contribution of SBP increases (C(i)) to short-term blood pressure variability was 52.8% (inter-quartile range: 50.9-55.1%) and median number of SBP increases (N(i)) was 48.8% (inter-quartile range: 47.2-50.1%). The C(i)>50% was found in 82% (P<0.0001; binomial test) and N(i)<50% in 75% (P<0.0001) of the subjects. Although SBP increases are significantly less abundant than reductions, their contribution to short-term blood pressure variability is significantly larger, which means that short-term blood pressure variability is asymmetric. SBP increases and reductions have unequal contribution to short-term blood pressure variability at supine rest in young healthy people. As this asymmetric behavior of blood pressure variability is present in most of the healthy studied people at rest, it can be concluded that blood pressure asymmetry is a physiological phenomenon.

  7. A Kinetic Model Unifying Presynaptic Short-Term Facilitation and Depression

    PubMed Central

    Lee, Chuang-Chung J.; Anton, Mihai; Poon, Chi-Sang; McRae, Gregory J.

    2009-01-01

    Short-term facilitation and depression refer to the increase and decrease of synaptic strength under repetitive stimuli within a timescale of milliseconds to seconds. This phenomenon has been attributed to primarily presynaptic mechanisms such as calcium-dependent transmitter release and presynaptic vesicle depletion. Previous modeling studies that aimed to integrate the complex short-term facilitation and short-term depression data derived from varying synapses have relied on computer simulation or abstract mathematical approaches. Here, we propose a unified theory of synaptic short-term plasticity based on realistic yet tractable and testable model descriptions of the underlying intracellular biochemical processes. Analysis of the model equations leads to a closed-form solution of the resonance frequency, a function of several critical biophysical parameters, as the single key indicator of the propensity for synaptic facilitation or depression under repetitive stimuli. This integrative model is supported by a broad range of transient and frequency response experimental data including those from facilitating, depressing or mixed-mode synapses. Specifically, the theory predicts that high calcium initial concentration and large gain of calcium action result in low resonance frequency and hence depressing behavior. In contrast, for synapses that are less sensitive to calcium or have higher recovery rate, resonance frequency becomes higher and thus facilitation prevails. The notion of resonance frequency therefore allows valuable quantitative parametric assessment of the contributions of various presynaptic mechanisms to the directionality of synaptic short-term plasticity. Thus, the model provides the reasons behind the switching behavior between facilitation and depression observed in experiments. New experiments are also suggested to control the short-term synaptic signal processing through adjusting the resonance frequency and bandwidth. PMID:19093195

  8. False memory for face in short-term memory and neural activity in human amygdala.

    PubMed

    Iidaka, Tetsuya; Harada, Tokiko; Sadato, Norihiro

    2014-12-03

    Human memory is often inaccurate. Similar to words and figures, new faces are often recognized as seen or studied items in long- and short-term memory tests; however, the neural mechanisms underlying this false memory remain elusive. In a previous fMRI study using morphed faces and a standard false memory paradigm, we found that there was a U-shaped response curve of the amygdala to old, new, and lure items. This indicates that the amygdala is more active in response to items that are salient (hit and correct rejection) compared to items that are less salient (false alarm), in terms of memory retrieval. In the present fMRI study, we determined whether the false memory for faces occurs within the short-term memory range (a few seconds), and assessed which neural correlates are involved in veridical and illusory memories. Nineteen healthy participants were scanned by 3T MRI during a short-term memory task using morphed faces. The behavioral results indicated that the occurrence of false memories was within the short-term range. We found that the amygdala displayed a U-shaped response curve to memory items, similar to those observed in our previous study. These results suggest that the amygdala plays a common role in both long- and short-term false memory for faces. We made the following conclusions: First, the amygdala is involved in detecting the saliency of items, in addition to fear, and supports goal-oriented behavior by modulating memory. Second, amygdala activity and response time might be related with a subject's response criterion for similar faces.

  9. Model documentation report: Short-Term Hydroelectric Generation Model

    SciTech Connect

    Not Available

    1993-08-01

    The purpose of this report is to define the objectives of the Short- Term Hydroelectric Generation Model (STHGM), describe its basic approach, and to provide details on the model structure. This report is intended as a reference document for model analysts, users, and the general public. Documentation of the model is in accordance with the Energy Information Administration`s (AYE) legal obligation to provide adequate documentation in support of its models (Public Law 94-385, Section 57.b.2). The STHGM performs a short-term (18 to 27- month) forecast of hydroelectric generation in the United States using an autoregressive integrated moving average (UREMIA) time series model with precipitation as an explanatory variable. The model results are used as input for the short-term Energy Outlook.

  10. Short-Termed Integrated Forecasting System: 1993 Model documentation report

    SciTech Connect

    Not Available

    1993-05-01

    The purpose of this report is to define the Short-Term Integrated Forecasting System (STIFS) and describe its basic properties. The Energy Information Administration (EIA) of the US Energy Department (DOE) developed the STIFS model to generate short-term (up to 8 quarters), monthly forecasts of US supplies, demands, imports exports, stocks, and prices of various forms of energy. The models that constitute STIFS generate forecasts for a wide range of possible scenarios, including the following ones done routinely on a quarterly basis: A base (mid) world oil price and medium economic growth. A low world oil price and high economic growth. A high world oil price and low economic growth. This report is written for persons who want to know how short-term energy markets forecasts are produced by EIA. The report is intended as a reference document for model analysts, users, and the public.

  11. Predicting short-term stock fluctuations by using processing fluency

    PubMed Central

    Alter, Adam L.; Oppenheimer, Daniel M.

    2006-01-01

    Three studies investigated the impact of the psychological principle of fluency (that people tend to prefer easily processed information) on short-term share price movements. In both a laboratory study and two analyses of naturalistic real-world stock market data, fluently named stocks robustly outperformed stocks with disfluent names in the short term. For example, in one study, an initial investment of $1,000 yielded a profit of $112 more after 1 day of trading for a basket of fluently named shares than for a basket of disfluently named shares. These results imply that simple, cognitive approaches to modeling human behavior sometimes outperform more typical, complex alternatives. PMID:16754871

  12. Short-term effect of antibiotics on human gut microbiota.

    PubMed

    Panda, Suchita; El khader, Ismail; Casellas, Francesc; López Vivancos, Josefa; García Cors, Montserrat; Santiago, Alba; Cuenca, Silvia; Guarner, Francisco; Manichanh, Chaysavanh

    2014-01-01

    From birth onwards, the human gut microbiota rapidly increases in diversity and reaches an adult-like stage at three years of age. After this age, the composition may fluctuate in response to external factors such as antibiotics. Previous studies have shown that resilience is not complete months after cessation of the antibiotic intake. However, little is known about the short-term effects of antibiotic intake on the gut microbial community. Here we examined the load and composition of the fecal microbiota immediately after treatment in 21 patients, who received broad-spectrum antibiotics such as fluoroquinolones and β-lactams. A fecal sample was collected from all participants before treatment and one week after for microbial load and community composition analyses by quantitative PCR and pyrosequencing of the 16S rRNA gene, respectively. Fluoroquinolones and β-lactams significantly decreased microbial diversity by 25% and reduced the core phylogenetic microbiota from 29 to 12 taxa. However, at the phylum level, these antibiotics increased the Bacteroidetes/Firmicutes ratio (p = 0.0007, FDR = 0.002). At the species level, our findings unexpectedly revealed that both antibiotic types increased the proportion of several unknown taxa belonging to the Bacteroides genus, a Gram-negative group of bacteria (p = 0.0003, FDR<0.016). Furthermore, the average microbial load was affected by the treatment. Indeed, the β-lactams increased it significantly by two-fold (p = 0.04). The maintenance of or possible increase detected in microbial load and the selection of Gram-negative over Gram-positive bacteria breaks the idea generally held about the effect of broad-spectrum antibiotics on gut microbiota.

  13. Improving creativity performance by short-term meditation

    PubMed Central

    2014-01-01

    Background One form of meditation intervention, the integrative body-mind training (IBMT) has been shown to improve attention, reduce stress and change self-reports of mood. In this paper we examine whether short-term IBMT can improve performance related to creativity and determine the role that mood may play in such improvement. Methods Forty Chinese undergraduates were randomly assigned to short-term IBMT group or a relaxation training (RT) control group. Mood and creativity performance were assessed by the Positive and Negative Affect Schedule (PANAS) and Torrance Tests of Creative Thinking (TTCT) questionnaire respectively. Results As predicted, the results indicated that short-term (30 min per day for 7 days) IBMT improved creativity performance on the divergent thinking task, and yielded better emotional regulation than RT. In addition, cross-lagged analysis indicated that both positive and negative affect may influence creativity in IBMT group (not RT group). Conclusions Our results suggested that emotion-related creativity-promoting mechanism may be attributed to short-term meditation. PMID:24645871

  14. The Precategorical Nature of Visual Short-Term Memory

    ERIC Educational Resources Information Center

    Quinlan, Philip T.; Cohen, Dale J.

    2016-01-01

    We conducted a series of recognition experiments that assessed whether visual short-term memory (VSTM) is sensitive to shared category membership of to-be-remembered (tbr) images of common objects. In Experiment 1 some of the tbr items shared the same basic level category (e.g., hand axe): Such items were no better retained than others. In the…

  15. Short-Term Effects of Televised Aggression on Children's Behavior.

    ERIC Educational Resources Information Center

    Liebert, Robert M.; Baron, Robert A.

    Recently collected data appear to warrant advancing some tentative conslusions concerning the short-term effects of violence in television on children: 1) children are exposed to a substantial amount of violent content on television, and they can remember and learn from such exposure; 2) correlational studies have disclosed a regular association…

  16. Validation of a Fish Short-term Reproduction Assay

    EPA Science Inventory

    The Fish Short-term Reproduction Assay is an in vivo assay conducted with fathead minnows and is designed to detect changes in spawning, gross morphology, histopathology, and specific biochemical endpoints that reflect disturbances in the hypothalamic-pituitary-gonadal (HPG) axis...

  17. 47 CFR 74.24 - Short-term operation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... in subparts D, E, F and H of this part, except wireless video assist devices, may be operated on a... notification provision shall not apply where an unanticipated need for immediate short-term mobile station... guidelines, which will be provided by Cornell University. In addition, the applicant shall indicate in...

  18. End Anchoring in Short-Term Order Memory

    ERIC Educational Resources Information Center

    Farrell, Simon; Lelievre, Anna

    2009-01-01

    Temporally grouping lists has systematic effects on immediate serial recall accuracy, order errors, and recall latencies, and is generally taken to reflect the use of multiple dimensions of ordering in short-term memory. It has been argued that these representations are fully relative, in that all sequence positions are anchored to both the start…

  19. Climax spent fuel dosimetry. Short term exposure, 8 March 1983

    SciTech Connect

    Quam, W.; DeVore, T.

    1984-06-01

    The second short-term exposure (performed 8 March 1983) in Hole CFH3 at the Climax Spent Fuel Test site is described. These short-term (1 hour long) exposures are intended to provide an independent measurement of the exposure rate at the wall and the 0.51-m and 0.66-m locations. Only CaF{sub 2} TLD`s were used in the second short-term exposure. Harshaw chips were cut to 0.32 x 0.18 x 0.09 cm size and aged by several exposure/readout/bakeout cycles until all odd chips were weeded out and the remaining chips exhibited stable sensitivities. Exposure at Climax was done by removing the existing long-term dosimetry strings and inserting identical strings using the CaF{sub 2} TLD`s in the stainless steel holders. The first short-term exposure produced absorbed doses as high as {similar_to}000 rads-LiF. The linearity corrections determined for the CaF{sub 2} TLD`s at these exposure levels were {similar_to}2%. The present post-exposure calibration method used calibration doses very close to those encountered in the field.

  20. Short-Term Memory, Executive Control, and Children's Route Learning

    ERIC Educational Resources Information Center

    Purser, Harry R. M.; Farran, Emily K.; Courbois, Yannick; Lemahieu, Axelle; Mellier, Daniel; Sockeel, Pascal; Blades, Mark

    2012-01-01

    The aim of this study was to investigate route-learning ability in 67 children aged 5 to 11 years and to relate route-learning performance to the components of Baddeley's model of working memory. Children carried out tasks that included measures of verbal and visuospatial short-term memory and executive control and also measures of verbal and…

  1. Short-term storage of Atlantic sturgeon spermatozoa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There is significant interest to restore the Atlantic sturgeon, a species of concern. Biologists are interested in both the short-term storage and cryopreservation of semen to maximize availability of viable spermatozoa whenever a rare ripe female is found and available for spawning. We conducted sh...

  2. The Role of Short-Term Memory in Operator Workload

    DTIC Science & Technology

    1988-04-01

    Baddeley, 1966; 1984), simultaneous digit processing ( Klapp and Philipoff, 1983), simultaneous, irrelevant articulation (articulatory suppression...Verbal Learning and Verbal Behavior, 1, 153-161. Klapp , S.T. and Philipoff, A., 1983, Short term memory limits in performance. Turning the tide of

  3. Regularization in Short-Term Memory for Serial Order

    ERIC Educational Resources Information Center

    Botvinick, Matthew; Bylsma, Lauren M.

    2005-01-01

    Previous research has shown that short-term memory for serial order can be influenced by background knowledge concerning regularities of sequential structure. Specifically, it has been shown that recall is superior for sequences that fit well with familiar sequencing constraints. The authors report a corresponding effect pertaining to serial…

  4. Assurance of Learning in Short-Term, Study Abroad Programs

    ERIC Educational Resources Information Center

    Tucker, Mary L.; Gullekson, Nicole L.; McCambridge, Jim

    2011-01-01

    Business students are increasingly seeking international experience in short-term, study abroad programs to enhance their intercultural knowledge, intercultural communication skills, and global perspectives to be more competitive in the global arena. Intuitively, universities initiating these programs and the students sojourning abroad believe in…

  5. Relation between Intelligence and Short-Term Memory

    ERIC Educational Resources Information Center

    Cohen, Ronald L.; Sandberg, Tor

    1977-01-01

    Intelligence and short-term memory correlations in children were measured using probed serial recall of supraspan digit lists. Results showed the predictive power of intelligence to range from a maximum in the case of recall for recency items to practically zero in the case of primacy items. (Author/MV)

  6. Short-Term International Experiences and Teacher Language Awareness

    ERIC Educational Resources Information Center

    Harbon, Lesley

    2007-01-01

    This research study had as its focus the impact of a short-term international experience on teacher language awareness (TLA). In-country intensive immersion experiences were considered beneficial for language teacher professional development. This project examined the Australian teachers' perceptions of their teaching and home-stay experiences…

  7. Short-term storage options for fresh-market onions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sweet onions have proven to be an excellent spring specialty crop in southeastern Oklahoma. Growers are interested in fuel-efficient methods of short term storage (up to 6 months) to lengthen market windows and enhance returns. Onions were seeded in high tunnels in November of 2005, transplanted to...

  8. Short-term energy outlook. Quarterly projections, second quarter 1996

    SciTech Connect

    1996-04-01

    The Energy Information Administration prepares quarterly, short-term energy supply, demand, and price projections. The forecasts in this issue cover the second quarter of 1996 through the fourth quarter of 1997. Changes to macroeconomic measures by the Bureau of Economic Analysis have been incorporated into the STIFS model used.

  9. Short-term energy outlook, Quarterly projections. Third quarter 1993

    SciTech Connect

    1993-08-04

    The Energy Information Administration (EIA) prepares quarterly, short-term energy supply, demand, and price projections for publication in February, May, August, and November in the Short-Term Energy Outlook (Outlook). An annual supplement analyzes the performance of previous forecasts, compares recent cases with those of other forecasting services, and discusses current topics related to the short-term energy markets. (See Short-Term Energy Outlook Annual Supplement, DOE/EIA-0202.) The forecast period for this issue of the Outlook extends from the third quarter of 1993 through the fourth quarter of 1994. Values for the second quarter of 1993, however, are preliminary EIA estimates (for example, some monthly values for petroleum supply and disposition are derived in part from weekly data reported in the Weekly Petroleum Status Report) or are calculated from model simulations using the latest exogenous information available (for example, electricity sales and generation are simulated using actual weather data). The historical energy data are EIA data published in the Monthly Energy Review, Petroleum Supply Monthly, and other EIA publications. Minor discrepancies between the data in these publications and the historical data in this Outlook are due to independent rounding.

  10. SHORT-TERM MEMORY IS INDEPENDENT OF BRAIN PROTEIN SYNTHESIS

    SciTech Connect

    Davis, Hasker P.; Rosenzweig, Mark R.; Jones, Oliver W.

    1980-09-01

    Male Swiss albino CD-1 mice given a single injection of a cerebral protein synthesis inhibitor, anisomycin (ANI) (1 mg/animal), 20 min prior to single trial passive avoidance training demonstrated impaired retention at tests given 3 hr, 6 hr, 1 day, and 7 days after training. Retention was not significantly different from saline controls when tests were given 0.5 or 1.5 hr after training. Prolonging inhibition of brain protein synthesis by giving either 1 or 2 additional injections of ANI 2 or 2 and 4 hr after training did not prolong short-term retention performance. The temporal development of impaired retention in ANI treated mice could not be accounted for by drug dosage, duration of protein synthesis inhibition, or nonspecific sickness at test. In contrast to the suggestion that protein synthesis inhibition prolongs short-term memory (Quinton, 1978), the results of this experiment indicate that short-term memory is not prolonged by antibiotic drugs that inhibit cerebral protein synthesis. All evidence seems consistent with the hypothesis that short-term memory is protein synthesis independent and that the establishment of long-term memory depends upon protein synthesis during or shortly after training. Evidence for a role of protein synthesis in memory maintenance is discussed.

  11. A DAPHNIA MAGNA SHORT-TERM SURVIVAL AND GROWTH TEST

    EPA Science Inventory

    With the change in acceptable test temperatures for invertebrate toxicity tests from <20oC to 25oC, it is now possible to use Daphnia magna for short-term chronic testing. When cultured at 25oC the dry weight of <24 hr old D. magna ranges from 7 to 15 g depending upon nutrition,...

  12. Selenium deficiency, reversible cardiomyopathy and short-term intravenous feeding.

    PubMed Central

    Levy, J. B.; Jones, H. W.; Gordon, A. C.

    1994-01-01

    We report the case of a patient with Crohn's disease receiving short-term postoperative parenteral nutrition supplemented with trace elements who nevertheless became selenium deficient with evidence of a cardiomyopathy. This was fully reversible with oral selenium supplementation. Current parenteral feeding regimes may not contain enough selenium for malnourished patients. PMID:8183763

  13. Exogenous Attention Influences Visual Short-Term Memory in Infants

    ERIC Educational Resources Information Center

    Ross-Sheehy, Shannon; Oakes, Lisa M.; Luck, Steven J.

    2011-01-01

    Two experiments examined the hypothesis that developing visual attentional mechanisms influence infants' Visual Short-Term Memory (VSTM) in the context of multiple items. Five- and 10-month-old infants (N = 76) received a change detection task in which arrays of three differently colored squares appeared and disappeared. On each trial one square…

  14. Short-Term Therapy: A Shift in Thinking.

    ERIC Educational Resources Information Center

    Fuhriman, Addie

    1992-01-01

    Responds to previous article by Steenbarger on science-practice integration in brief counseling and therapy. Considers three dimensions that emerge from the integrated analysis presented in Steenbarger's article: catalysis, involvement, and time. Discusses each of these three characteristics as they are related specifically to a short-term format.…

  15. Pigeon visual short-term memory directly compared to primates.

    PubMed

    Wright, Anthony A; Elmore, L Caitlin

    2016-02-01

    Three pigeons were trained to remember arrays of 2-6 colored squares and detect which of two squares had changed color to test their visual short-term memory. Procedures (e.g., stimuli, displays, viewing times, delays) were similar to those used to test monkeys and humans. Following extensive training, pigeons performed slightly better than similarly trained monkeys, but both animal species were considerably less accurate than humans with the same array sizes (2, 4 and 6 items). Pigeons and monkeys showed calculated memory capacities of one item or less, whereas humans showed a memory capacity of 2.5 items. Despite the differences in calculated memory capacities, the pigeons' memory results, like those from monkeys and humans, were all well characterized by an inverse power-law function fit to d' values for the five display sizes. This characterization provides a simple, straightforward summary of the fundamental processing of visual short-term memory (how visual short-term memory declines with memory load) that emphasizes species similarities based upon similar functional relationships. By closely matching pigeon testing parameters to those of monkeys and humans, these similar functional relationships suggest similar underlying processes of visual short-term memory in pigeons, monkeys and humans.

  16. Writing Better Goals and Short-Term Objectives or Benchmarks.

    ERIC Educational Resources Information Center

    Lignugaris/Kraft, Benjamin; Marchand-Martella, Nancy; Martella, Ronald C.

    2001-01-01

    This article provides strategies for writing precise goals and short-term objectives or benchmarks as part of individualized education programs (IEPs). Guidelines and examples address: definitions, reasons for clarity and precision, individual parts of goals and objectives, inclusion of time factors in objectives and benchmarks, number of…

  17. Visual Short-Term Memory During Smooth Pursuit Eye Movements

    ERIC Educational Resources Information Center

    Kerzel, Dirk; Ziegler, Nathalie E.

    2005-01-01

    Visual short-term memory (VSTM) was probed while observers performed smooth pursuit eye movements. Smooth pursuit keeps a moving object stabilized in the fovea. VSTM capacity for position was reduced during smooth pursuit compared with a condition with eye fixation. There was no difference between a condition in which the items were approximately…

  18. 77 FR 61229 - Short-Term Investment Funds

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-09

    ... resilience of STIFs to credit and liquidity events while not unduly restricting a bank's ability to invest... liquidity or valuation stress. \\29\\ See Interagency Policy on Banks/Thrifts Providing Financial Support to... revises the requirements imposed on national banks pursuant to the OCC's short-term investment fund...

  19. CONTROLLED, SHORT-TERM DERMAL AND INHALATION EXPOSURE TO CHLOROFORM

    EPA Science Inventory

    Studies were conducted to determine the uptake by humans of chloroform as a result of controlled short-term dermal and inhalation exposures. The approach used continuous real-time breath analysis to determine exhaled-breath profiles and evaluate chloroform kinetics in the huma...

  20. A SHORT-TERM TERMINAL COURSE FOR POTENTIAL DROPOUTS.

    ERIC Educational Resources Information Center

    CANGEMI, JOSEPH P.

    STUDENTS IDENTIFIED AS "HARD-CORE" FUTURE DROPOUTS BY COUNSELORS, TEACHERS, AND SCHOOL ADMINISTRATORS SHOULD BE GROUPED TOGETHER FOR A COMPREHENSIVE, SHORT-TERM COURSE. SOME OF THE REALISTIC OBJECTIVES OF A TERMINAL PROGRAM FOR POTENTIAL DROPOUTS ARE--TO PREPARE STUDENTS WHO ARE DROPPING OUT OF SCHOOL FOR IMMEDIATE EMPLOYMENT, TO…

  1. Interference-Based Forgetting in Verbal Short-Term Memory

    ERIC Educational Resources Information Center

    Lewandowsky, Stephan; Geiger, Sonja M.; Oberauer, Klaus

    2008-01-01

    This article presents four experiments that tested predictions of SOB (Serial Order in a Box), an interference-based theory of short-term memory. Central to SOB is the concept of novelty-sensitive encoding, which holds that items are encoded to the extent that they differ from already-encoded information. On the additional assumption that…

  2. Emotive-reconstruction psychotherapy: a short-term cognitive approach.

    PubMed

    Morrison, J K; Cometa, M S

    1977-04-01

    Emotive-Reconstructive Therapy, a recently developed therapeutic modality deriving from cognitive theory, may be a promising short-term approach to psychopathology. Combining the use of imagery with selective hyperventilation, a therapist induces patients to reexperience past events, and subsequently to radically reconstrue themselves and significant others in a personally satisfying direction.

  3. Enhanced Visual Short-Term Memory for Angry Faces

    ERIC Educational Resources Information Center

    Jackson, Margaret C.; Wu, Chia-Yun; Linden, David E. J.; Raymond, Jane E.

    2009-01-01

    Although some views of face perception posit independent processing of face identity and expression, recent studies suggest interactive processing of these 2 domains. The authors examined expression-identity interactions in visual short-term memory (VSTM) by assessing recognition performance in a VSTM task in which face identity was relevant and…

  4. Short-Term Effects of Playing Computer Games on Attention

    ERIC Educational Resources Information Center

    Tahiroglu, Aysegul Yolga; Celik, Gonca Gul; Avci, Ayse; Seydaoglu, Gulsah; Uzel, Mehtap; Altunbas, Handan

    2010-01-01

    Objective: The main aim of the present study is to investigate the short-term cognitive effects of computer games in children with different psychiatric disorders and normal controls. Method: One hundred one children are recruited for the study (aged between 9 and 12 years). All participants played a motor-racing game on the computer for 1 hour.…

  5. Presynaptic learning and memory with a persistent firing neuron and a habituating synapse: a model of short term persistent habituation.

    PubMed

    Ramanathan, Kiruthika; Ning, Ning; Dhanasekar, Dhiviya; Li, Guoqi; Shi, Luping; Vadakkepat, Prahlad

    2012-08-01

    Our paper explores the interaction of persistent firing axonal and presynaptic processes in the generation of short term memory for habituation. We first propose a model of a sensory neuron whose axon is able to switch between passive conduction and persistent firing states, thereby triggering short term retention to the stimulus. Then we propose a model of a habituating synapse and explore all nine of the behavioral characteristics of short term habituation in a two neuron circuit. We couple the persistent firing neuron to the habituation synapse and investigate the behavior of short term retention of habituating response. Simulations show that, depending on the amount of synaptic resources, persistent firing either results in continued habituation or maintains the response, both leading to longer recovery times. The effectiveness of the model as an element in a bio-inspired memory system is discussed.

  6. Visual short-term memory deficits in REM sleep behaviour disorder mirror those in Parkinson's disease.

    PubMed

    Rolinski, Michal; Zokaei, Nahid; Baig, Fahd; Giehl, Kathrin; Quinnell, Timothy; Zaiwalla, Zenobia; Mackay, Clare E; Husain, Masud; Hu, Michele T M

    2016-01-01

    Individuals with REM sleep behaviour disorder are at significantly higher risk of developing Parkinson's disease. Here we examined visual short-term memory deficits--long associated with Parkinson's disease--in patients with REM sleep behaviour disorder without Parkinson's disease using a novel task that measures recall precision. Visual short-term memory for sequentially presented coloured bars of different orientation was assessed in 21 patients with polysomnography-proven idiopathic REM sleep behaviour disorder, 26 cases with early Parkinson's disease and 26 healthy controls. Three tasks using the same stimuli controlled for attentional filtering ability, sensorimotor and temporal decay factors. Both patients with REM sleep behaviour disorder and Parkinson's disease demonstrated a deficit in visual short-term memory, with recall precision significantly worse than in healthy controls with no deficit observed in any of the control tasks. Importantly, the pattern of memory deficit in both patient groups was specifically explained by an increase in random responses. These results demonstrate that it is possible to detect the signature of memory impairment associated with Parkinson's disease in individuals with REM sleep behaviour disorder, a condition associated with a high risk of developing Parkinson's disease. The pattern of visual short-term memory deficit potentially provides a cognitive marker of 'prodromal' Parkinson's disease that might be useful in tracking disease progression and for disease-modifying intervention trials.

  7. Neural mechanisms of short-term plasticity in the human visual system.

    PubMed

    Parks, Nathan A; Corballis, Paul M

    2012-12-01

    Following circumscribed retinal damage, extensive reorganization of topographically organized visual cortical areas has been demonstrated in several species of mammals (including humans). Although reorganization is often studied over extended time scales, neural response properties change within seconds of retinal deafferentation. Understanding the mechanisms underlying these short-term effects is essential for developing a complete picture of representational plasticity. One approach to the study of short-term plasticity has been to use an artificial scotoma, a stimulus-induced analog of a retinal scotoma, as a model. Here, we use event-related potentials in an artificial scotoma paradigm to examine 2 aspects of short-term plasticity in the human visual system. First, we investigated the changes within visual representations temporarily deprived of patterned visual input by probing the inner boundaries of an artificial scotoma. We found an enhanced early sensory P1, consistent with a reduction in inhibition (disinhibition), a proposed mechanism of short-term visual plasticity. Second, we investigated mechanisms through which representations of surrounding space invade a visually deprived area by probing the outer boundaries of an artificial scotoma. In this case, a later visual component, the N1, was enhanced, suggesting that feedback may provide a source of unmasked, or invading, activity to visually deprived representations.

  8. Do It Now: Short-Term Responses to Traumatic Events

    ERIC Educational Resources Information Center

    Demaria, Thomas; Schonfeld, David J.

    2014-01-01

    Traumatic crises can have a lifelong effect. The majority of children, however, will not develop lasting problems following a crisis. The immediate goal of the school is to minimize the negative impact, support coping, accelerate adjustment, and instill confidence in students that school staff is available to address their needs. Support and…

  9. Short-term response of testate amoebae to wildfire

    NASA Astrophysics Data System (ADS)

    Qin, Yangmin

    2016-04-01

    Many peatlands are exposed to intermittent burning but the implications of this burning for microbial communities have been little studied. Here we consider the impacts of burning on the dominant protists of peatland ecosystems, the testate amoebae. To do this we use a 'natural experiment'; a peatland exposed to wildfire where fire-fighting activity left a combination of unburned and heavily burned areas in close proximity. We assessed the change in testate amoebae three days after the end of the fire. We find that burning led to a large change in assemblage composition, primarily noted by a shift from taxa with tests constructed of idiosomes to those constructed of xenosomes. The most likely explanation for this change is the direct destruction of idiosome tests by extreme heat. Although we did not differentiate live individuals from empty tests it is probable that the fire has led to significant change in the amoeba community. This change may have interesting implications for the structure of the microbial foodweb, for silica cycling and for palaeoecological reconstruction in burned peatlands. This is clearly a topic which deserves more research attention.

  10. Ordered Short-Term Memory Differs in Signers and Speakers: Implications for Models of Short-Term Memory

    ERIC Educational Resources Information Center

    Bavelier, Daphne; Newport, Elissa L.; Hall, Matt; Supalla, Ted; Boutla, Mrim

    2008-01-01

    Capacity limits in linguistic short-term memory (STM) are typically measured with forward span tasks in which participants are asked to recall lists of words in the order presented. Using such tasks, native signers of American Sign Language (ASL) exhibit smaller spans than native speakers ([Boutla, M., Supalla, T., Newport, E. L., & Bavelier, D.…

  11. Short-Term Analysis of Human Dental Pulps After Direct Capping with Portland Cement

    PubMed Central

    Barbosa, Antonio Vinicius Holanda; Sampaio, Gerhilde Callou; Gomes, Fábio Almeida; de Oliveira, Daniel Pinto; de Albuquerque, Diana Santana; Sobral, Ana Paula Veras

    2009-01-01

    This study evaluated the short-term response of human pulp tissue when directly capped with Portland cement. In this series of cases, twenty human third molars that were scheduled for extraction were used. After cavity preparation, pulp exposure was achieved and Portland cement pulp capping was performed. Teeth were extracted after 1, 7, 14 and 21 days following treatment and prepared for histological examination and bacterial detection. Each group had 5 teeth. The results were descriptively analysed. Dentin bridge formation was seen in two teeth with some distance from the material interface (14 and 21 days). Soft inflammatory responses were observed in most of the cases. Bacteria were not disclosed in any specimen. PC exhibited some features of biocompatibility and capability of inducing mineral pulp response in short-term evaluation. The results suggested that PC has a potential to be used as a less expensive pulp capping material in comparison to other pulp capping materials. PMID:19444341

  12. Short-term analysis of human dental pulps after direct capping with portland cement.

    PubMed

    Barbosa, Antonio Vinicius Holanda; Sampaio, Gerhilde Callou; Gomes, Fábio Almeida; de Oliveira, Daniel Pinto; de Albuquerque, Diana Santana; Sobral, Ana Paula Veras

    2009-03-17

    This study evaluated the short-term response of human pulp tissue when directly capped with Portland cement. In this series of cases, twenty human third molars that were scheduled for extraction were used. After cavity preparation, pulp exposure was achieved and Portland cement pulp capping was performed. Teeth were extracted after 1, 7, 14 and 21 days following treatment and prepared for histological examination and bacterial detection. Each group had 5 teeth. The results were descriptively analysed. Dentin bridge formation was seen in two teeth with some distance from the material interface (14 and 21 days). Soft inflammatory responses were observed in most of the cases. Bacteria were not disclosed in any specimen. PC exhibited some features of biocompatibility and capability of inducing mineral pulp response in short-term evaluation. The results suggested that PC has a potential to be used as a less expensive pulp capping material in comparison to other pulp capping materials.

  13. Comparison on Response and Dissolution Rates Between Ursodeoxycholic Acid Alone or in Combination With Chenodeoxycholic Acid for Gallstone Dissolution According to Stone Density on CT Scan: Strobe Compliant Observation Study.

    PubMed

    Lee, Jae Min; Hyun, Jong Jin; Choi, In Young; Yeom, Suk Keu; Kim, Seung Young; Jung, Sung Woo; Jung, Young Kul; Koo, Ja Seol; Yim, Hyung Joon; Lee, Hong Sik; Lee, Sang Woo; Kim, Chang Duck

    2015-12-01

    Medical dissolution of gallstone is usually performed on radiolucent gallstones in a functioning gallbladder. However, absence of visible gallstone on plain abdominal x-ray does not always preclude calcification. This study aims to compare the response and dissolution rates between ursodeoxycholic acid (UDCA) alone or in combination with chenodeoxycholic acid (CDCA) according to stone density on computed tomography (CT) scan. A total of 126 patients underwent dissolution therapy with either UDCA alone or combination of CDCA and UDCA (CNU) from December 2010 to March 2014 at Korea University Ansan Hospital. In the end, 81 patients (CNU group = 44, UDCA group = 37) completed dissolution therapy for 6 months. Dissolution rate (percentage reduction in the gallstone volume) and response to therapy (complete dissolution or partial dissolution defined as reduction in stone volume of >50%) were compared between the 2 groups. Dissolution and response rates of sludge was also compared between the 2 groups. The overall response rate was 50.6% (CNU group 43.2% vs UDCA group 59.5%, P = 0.14), and the overall dissolution rate was 48.34% (CNU group 41.5% vs UDCA group 56.5%, P = 0.13). When analyzed according to stone density, response rate was 33.3%, 87.1%, 30.0%, and 6.2% for hypodense, isodense, hyperdense, and calcified stones, respectively. Response rate (85.7% vs 88.2%, P = 0.83) and dissolution rate (81.01% vs 85.38%, P = 0.17) of isodense stones were similar between CNU and UDCA group. When only sludge was considered, the overall response rate was 87.5% (CNU group 71.4% vs UDCA group 94.1%, P = 0.19), and the overall dissolution rate was 85.42% (CNU group 67.9% vs UDCA group 92.7%, P = 0.23). Patients with isodense gallstones and sludge showed much better response to dissolution therapy with CNU and UDCA showing comparable efficacy. Therefore, CT scan should be performed before medication therapy if stone dissolution is intended.

  14. Effects of sleep deprivation on short-term recognition memory.

    PubMed

    Polzella, D J

    1975-03-01

    A probe-recognition short-term memory paradigm was used to inquire into the precise effects of sleep deprivation on human memory. It was found that recognition performance, as measured by d', was generally impaired for each subjects after 24 hr of sleep deprivation. While d' was shown to decrease exponentially as the number of items intervening between the target and the probe increased, this decay rate was not affected by sleep loss. In addition there was confirmation of a previously observed increase in the positive skewness of reaction times after wakefulness. The data were consistent with the hypothesis that sleep deprivation increases the occurrence of lapses, periods of lowered reactive capacity, which prevent the encoding of items in short-term memory.

  15. The psychotomimetic effects of short-term sensory deprivation.

    PubMed

    Mason, Oliver J; Brady, Francesca

    2009-10-01

    People experiencing sensory deprivation often report perceptual disturbances such as hallucinations, especially over extended periods of time. However, there is little evidence concerning short-term sensory deprivation and whether its effects differ depending on the individual concerned, and in particular their proneness to psychosis. This study explored whether perceptual disturbances could be elicited by a brief period of complete isolation from sound and vision in both highly hallucination prone and nonhallucination prone groups. Greater psychotomimetic experiences taking the form of perceptual disturbances, paranoia, and anhedonia were found across both groups when under sensory deprivation. In addition, hallucination-prone individuals experienced more perceptual disturbances when placed in short-term sensory deprivation than nonprone individuals. This result is discussed in terms of difficulties in source monitoring as a possible mechanism involved in proneness to hallucinations.

  16. Short-term hydroelectric generation model. Model documentation report

    SciTech Connect

    1996-12-01

    The purpose of this report is to define the objectives of the Energy Information Administration`s (EIA) Short-Term Hydroelectric Generation Model (STHGM), describe its basic approach, and to provide details on the model structure. This report is intended as a reference document for model analysts, users, and the general public. Documentation of the model is in accordance with the EIA`s legal obligation to provide adequate documentation in support of its models.

  17. Electricity price short-term forecasting using artificial neural networks

    SciTech Connect

    Szkuta, B.R.; Sanabria, L.A.; Dillon, T.S.

    1999-08-01

    This paper presents the System Marginal Price (SMP) short-term forecasting implementation using the Artificial Neural Networks (ANN) computing technique. The described approach uses the three-layered ANN paradigm with back-propagation. The retrospective SMP real-world data, acquired from the deregulated Victorian power system, was used for training and testing the ANN. The results presented in this paper confirm considerable value of the ANN based approach in forecasting the SMP.

  18. Auditory short-term memory activation during score reading.

    PubMed

    Simoens, Veerle L; Tervaniemi, Mari

    2013-01-01

    Performing music on the basis of reading a score requires reading ahead of what is being played in order to anticipate the necessary actions to produce the notes. Score reading thus not only involves the decoding of a visual score and the comparison to the auditory feedback, but also short-term storage of the musical information due to the delay of the auditory feedback during reading ahead. This study investigates the mechanisms of encoding of musical information in short-term memory during such a complicated procedure. There were three parts in this study. First, professional musicians participated in an electroencephalographic (EEG) experiment to study the slow wave potentials during a time interval of short-term memory storage in a situation that requires cross-modal translation and short-term storage of visual material to be compared with delayed auditory material, as it is the case in music score reading. This delayed visual-to-auditory matching task was compared with delayed visual-visual and auditory-auditory matching tasks in terms of EEG topography and voltage amplitudes. Second, an additional behavioural experiment was performed to determine which type of distractor would be the most interfering with the score reading-like task. Third, the self-reported strategies of the participants were also analyzed. All three parts of this study point towards the same conclusion according to which during music score reading, the musician most likely first translates the visual score into an auditory cue, probably starting around 700 or 1300 ms, ready for storage and delayed comparison with the auditory feedback.

  19. Auditory Short-Term Memory Activation during Score Reading

    PubMed Central

    Simoens, Veerle L.; Tervaniemi, Mari

    2013-01-01

    Performing music on the basis of reading a score requires reading ahead of what is being played in order to anticipate the necessary actions to produce the notes. Score reading thus not only involves the decoding of a visual score and the comparison to the auditory feedback, but also short-term storage of the musical information due to the delay of the auditory feedback during reading ahead. This study investigates the mechanisms of encoding of musical information in short-term memory during such a complicated procedure. There were three parts in this study. First, professional musicians participated in an electroencephalographic (EEG) experiment to study the slow wave potentials during a time interval of short-term memory storage in a situation that requires cross-modal translation and short-term storage of visual material to be compared with delayed auditory material, as it is the case in music score reading. This delayed visual-to-auditory matching task was compared with delayed visual-visual and auditory-auditory matching tasks in terms of EEG topography and voltage amplitudes. Second, an additional behavioural experiment was performed to determine which type of distractor would be the most interfering with the score reading-like task. Third, the self-reported strategies of the participants were also analyzed. All three parts of this study point towards the same conclusion according to which during music score reading, the musician most likely first translates the visual score into an auditory cue, probably starting around 700 or 1300 ms, ready for storage and delayed comparison with the auditory feedback. PMID:23326487

  20. Short term UV line profile variation in 59 Cyg

    NASA Technical Reports Server (NTRS)

    Grady, C. A.; Doazan, V.; Peters, G. J.; Willis, A.; Snow, T. P.; Aitken, D.; Barker, P. K.; Bolton, C. T.; Henrichs, H.; Kitchen, C. R.

    1982-01-01

    The International ultraviolet Explorer high dispersion spectra of 59 Cyg obtained as part of the long term monitoring program have shown that noticeable variation can occur in C 5 and N 5 on timescales 3 hours t24 to 28 hours. In order to begin to resolve whether these changes occur continuously or sporadically, 48 hours were devoted to monitoring this star in January 1982. The January spectra show no short term variation, which may be consistent with sporadic rather than continuous variation.

  1. Research about Short- Term Production Capacity Decision-Making

    NASA Astrophysics Data System (ADS)

    bi-xi, Zhang; jing, Song; xiu-li, Yu

    Under the circumstances of uncertain fluctuation of market demand, the degree of matching between production capacity and customers demand can affect the cost, the efficiency and the profits of an enterprise. Choosing the appropriate production capacity level is an important task for decision makers. The paper analyzes the characters of the short-term demand variation, the matching between the capacity and the demand, and its influence on the enterprise. Supposing the short-term demand varies seasonally, and the objective is minimum the loss of mismatch between the production capacity and market demand.Then,short-term production capacity decision model has been developed.Based on the model, this paper has probed into the mismatching loss of three strategies: fixed capacity strategy, subsection adjustment capacity strategy and dynamic adjustment capacity strategy,and an optimal capacity strategy is provided. By fixing the capacity-demand mismatching loss and changing the capacity adjustment rate, this paper also studies the sensitivity of the capacity strategy. The result shows that, firstly, as the capacity adjustment rate is less than a certain numerical value, the dynamic adjustment capacity is the optimal choice; secondly, as the capacity adjustment rate exceeds a certain numerical value, the optimal one is fixed capacity strategy; finally, as the rate falls in some specific area, the optimal one is subsection adjustment capacity strategy. One practical example is provided to prove the model's validity.

  2. Short-term energy outlook: Quarterly projections, fourth quarter 1997

    SciTech Connect

    1997-10-14

    The Energy Information Administration (EIA) prepares quarterly short-term energy supply, demand, and price projections for printed publication in January, April, July, and October in the Short-Term Energy Outlook. The details of these projections, as well as monthly updates on or about the 6th of each interim month, are available on the internet at: www.eia.doe.gov/emeu/steo/pub/contents.html. The forecast period for this issue of the Outlook extends from the fourth quarter of 1997 through the fourth quarter of 1998. Values for the fourth quarter of 1997, however, are preliminary EIA estimates (for example, some monthly values for petroleum supply and disposition are derived in part from weekly data reported in EIA`s Weekly Petroleum Status Report) or are calculated from model simulations that use the latest exogenous information available (for example, electricity sales and generation are simulated by using actual weather data). The historical energy data, compiled in the fourth quarter 1997 version of the Short-Term Integrated Forecasting System (STIFS) database, are mostly EIA data regularly published in the Monthly Energy Review, Petroleum Supply Monthly, and other EIA publications. Minor discrepancies between the data in these publications and the historical data in this Outlook are due to independent rounding. The STIFS model is driven principally by three sets of assumptions or inputs: estimates of key macroeconomic variables, world oil price assumptions, and assumptions about the severity of weather. 19 tabs.

  3. 2-arachidonoylglycerol signaling impairs short-term fear extinction.

    PubMed

    Hartley, N D; Gunduz-Cinar, O; Halladay, L; Bukalo, O; Holmes, A; Patel, S

    2016-03-01

    Impairments in fear extinction are thought to be central to the psychopathology of posttraumatic stress disorder, and endocannabinoid (eCB) signaling has been strongly implicated in extinction learning. Here we utilized the monoacylglycerol lipase inhibitor JZL184 to selectively augment brain 2-AG levels combined with an auditory cue fear-conditioning paradigm to test the hypothesis that 2-AG-mediated eCB signaling modulates short-term fear extinction learning in mice. We show that systemic JZL184 impairs short-term extinction learning in a CB1 receptor-dependent manner without affecting non-specific freezing behavior or the acquisition of conditioned fear. This effect was also observed in over-conditioned mice environmentally manipulated to re-acquire fear extinction. Cumulatively, the effects of JZL184 appear to be partly due to augmentation of 2-AG signaling in the basolateral nucleus of the amygdala (BLA), as direct microinfusion of JZL184 into the BLA produced similar results. Moreover, we elucidate a short ~3-day temporal window during which 2-AG augmentation impairs extinction behavior, suggesting a preferential role for 2-AG-mediated eCB signaling in the modulation of short-term behavioral sequelae to acute traumatic stress exposure.

  4. 2-arachidonoylglycerol signaling impairs short-term fear extinction

    PubMed Central

    Hartley, N D; Gunduz-Cinar, O; Halladay, L; Bukalo, O; Holmes, A; Patel, S

    2016-01-01

    Impairments in fear extinction are thought to be central to the psychopathology of posttraumatic stress disorder, and endocannabinoid (eCB) signaling has been strongly implicated in extinction learning. Here we utilized the monoacylglycerol lipase inhibitor JZL184 to selectively augment brain 2-AG levels combined with an auditory cue fear-conditioning paradigm to test the hypothesis that 2-AG-mediated eCB signaling modulates short-term fear extinction learning in mice. We show that systemic JZL184 impairs short-term extinction learning in a CB1 receptor-dependent manner without affecting non-specific freezing behavior or the acquisition of conditioned fear. This effect was also observed in over-conditioned mice environmentally manipulated to re-acquire fear extinction. Cumulatively, the effects of JZL184 appear to be partly due to augmentation of 2-AG signaling in the basolateral nucleus of the amygdala (BLA), as direct microinfusion of JZL184 into the BLA produced similar results. Moreover, we elucidate a short ~3-day temporal window during which 2-AG augmentation impairs extinction behavior, suggesting a preferential role for 2-AG-mediated eCB signaling in the modulation of short-term behavioral sequelae to acute traumatic stress exposure. PMID:26926885

  5. Short-term memory deficits correlate with hippocampal-thalamic functional connectivity alterations following acute sleep restriction.

    PubMed

    Chengyang, Li; Daqing, Huang; Jianlin, Qi; Haisheng, Chang; Qingqing, Meng; Jin, Wang; Jiajia, Liu; Enmao, Ye; Yongcong, Shao; Xi, Zhang

    2016-07-21

    Acute sleep restriction heavily influences cognitive function, affecting executive processes such as attention, response inhibition, and memory. Previous neuroimaging studies have suggested a link between hippocampal activity and short-term memory function. However, the specific contribution of the hippocampus to the decline of short-term memory following sleep restriction has yet to be established. In the current study, we utilized resting-state functional magnetic resonance imaging (fMRI) to examine the association between hippocampal functional connectivity (FC) and the decline of short-term memory following total sleep deprivation (TSD). Twenty healthy adult males aged 20.9 ± 2.3 years (age range, 18-24 years) were enrolled in a within-subject crossover study. Short-term memory and FC were assessed using a Delay-matching short-term memory test and a resting-state fMRI scan before and after TSD. Seed-based correlation analysis was performed using fMRI data for the left and right hippocampus to identify differences in hippocampal FC following TSD. Subjects demonstrated reduced alertness and a decline in short-term memory performance following TSD. Moreover, fMRI analysis identified reduced hippocampal FC with the superior frontal gyrus (SFG), temporal regions, and supplementary motor area. In addition, an increase in FC between the hippocampus and bilateral thalamus was observed, the extent of which correlated with short-term memory performance following TSD. Our findings indicate that the disruption of hippocampal-cortical connectivity is linked to the decline in short-term memory observed after acute sleep restriction. Such results provide further evidence that support the cognitive impairment model of sleep deprivation.

  6. Perceptions of the Role of Short-Term Volunteerism in International Development: Views from Volunteers, Local Hosts, and Community Members

    PubMed Central

    Loiseau, Bethina; Sibbald, Rebekah; Raman, Salem A.; Darren, Benedict; Loh, Lawrence C.

    2016-01-01

    Background. Short-term international volunteer trips traditionally involve volunteers from high-income countries travelling to low- and middle-income countries to assist in service-related development activities. Their duration typically ranges from 7 to 90 days. The city of La Romana, Dominican Republic, receives hundreds of short-term international volunteers annually. They participate in activities aimed at improving conditions faced by a marginalized ethnic-Haitian community living in bateyes. Methods. This qualitative analysis examined perceptions of short-term international volunteerism, held by three key stakeholder groups in La Romana: local hosts, international volunteers, and community members. Responses from semistructured interviews were recorded and analysed by thematic analysis. Results. Themes from the 3 groups were broadly categorized into general perceptions of short-term volunteerism and proposed best practices. These were further subdivided into perceptions of value, harms, and motivations associated with volunteer teams for the former and best practices around volunteer composition and selection, partnership, and skill sets and predeparture training for the latter. Conclusion. Notable challenges were associated with short-term volunteering, including an overemphasis on the material benefits from volunteer groups expressed by community member respondents; misalignment of the desired and actual skill sets of volunteers; duplicate and uncoordinated volunteer efforts; and the perpetuation of stereotypes suggesting that international volunteers possess superior knowledge or skills. Addressing these challenges is critical to optimizing the conduct of short-term volunteerism. PMID:27382372

  7. Short-Term Energy Outlook Supplement: Key drivers for EIA's short-term U.S. crude oil production outlook

    EIA Publications

    2013-01-01

    Crude oil production increased by 790,000 barrels per day (bbl/d) between 2011 and 2012, the largest increase in annual output since the beginning of U.S. commercial crude oil production in 1859. The U.S. Energy Information Administration (EIA) expects U.S. crude oil production to continue rising over the next two years represented in the Short-Term Energy Outlook (STEO).

  8. Short term synaptic depression imposes a frequency dependent filter on synaptic information transfer.

    PubMed

    Rosenbaum, Robert; Rubin, Jonathan; Doiron, Brent

    2012-01-01

    Depletion of synaptic neurotransmitter vesicles induces a form of short term depression in synapses throughout the nervous system. This plasticity affects how synapses filter presynaptic spike trains. The filtering properties of short term depression are often studied using a deterministic synapse model that predicts the mean synaptic response to a presynaptic spike train, but ignores variability introduced by the probabilistic nature of vesicle release and stochasticity in synaptic recovery time. We show that this additional variability has important consequences for the synaptic filtering of presynaptic information. In particular, a synapse model with stochastic vesicle dynamics suppresses information encoded at lower frequencies more than information encoded at higher frequencies, while a model that ignores this stochasticity transfers information encoded at any frequency equally well. This distinction between the two models persists even when large numbers of synaptic contacts are considered. Our study provides strong evidence that the stochastic nature neurotransmitter vesicle dynamics must be considered when analyzing the information flow across a synapse.

  9. Self-tuning of neural circuits through short-term synaptic plasticity.

    PubMed

    Sussillo, David; Toyoizumi, Taro; Maass, Wolfgang

    2007-06-01

    Numerous experimental data show that cortical networks of neurons are not silent in the absence of external inputs, but rather maintain a low spontaneous firing activity. This aspect of cortical networks is likely to be important for their computational function, but is hard to reproduce in models of cortical circuits of neurons because the low-activity regime is inherently unstable. Here we show-through theoretical analysis and extensive computer simulations-that short-term synaptic plasticity endows models of cortical circuits with a remarkable stability in the low-activity regime. This short-term plasticity works as a homeostatic mechanism that stabilizes the overall activity level in spite of drastic changes in external inputs and internal circuit properties, while preserving reliable transient responses to signals. The contribution of synaptic dynamics to this stability can be predicted on the basis of general principles from control theory.

  10. Spatial short-term memory in children with nonverbal learning disabilities: impairment in encoding spatial configuration.

    PubMed

    Narimoto, Tadamasa; Matsuura, Naomi; Takezawa, Tomohiro; Mitsuhashi, Yoshinori; Hiratani, Michio

    2013-01-01

    The authors investigated whether impaired spatial short-term memory exhibited by children with nonverbal learning disabilities is due to a problem in the encoding process. Children with or without nonverbal learning disabilities performed a simple spatial test that required them to remember 3, 5, or 7 spatial items presented simultaneously in random positions (i.e., spatial configuration) and to decide if a target item was changed or all items including the target were in the same position. The results showed that, even when the spatial positions in the encoding and probe phases were similar, the mean proportion correct of children with nonverbal learning disabilities was 0.58 while that of children without nonverbal learning disabilities was 0.84. The authors argue with the results that children with nonverbal learning disabilities have difficulty encoding relational information between spatial items, and that this difficulty is responsible for their impaired spatial short-term memory.

  11. Factors Influencing Short-term Synaptic Plasticity in the Avian Cochlear Nucleus Magnocellularis

    PubMed Central

    Sanchez, Jason Tait; Quinones, Karla; Otto-Meyer, Sebastian

    2015-01-01

    Defined as reduced neural responses during high rates of activity, synaptic depression is a form of short-term plasticity important for the temporal filtering of sound. In the avian cochlear nucleus magnocellularis (NM), an auditory brainstem structure, mechanisms regulating short-term synaptic depression include pre-, post-, and extrasynaptic factors. Using varied paired-pulse stimulus intervals, we found that the time course of synaptic depression lasts up to four seconds at late-developing NM synapses. Synaptic depression was largely reliant on exogenous Ca2+-dependent probability of presynaptic neurotransmitter release, and to a lesser extent, on the desensitization of postsynaptic α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid-type glutamate receptor (AMPA-R). Interestingly, although extrasynaptic glutamate clearance did not play a significant role in regulating synaptic depression, blocking glutamate clearance at early-developing synapses altered synaptic dynamics, changing responses from depression to facilitation. These results suggest a developmental shift in the relative reliance on pre-, post-, and extrasynaptic factors in regulating short-term synaptic plasticity in NM. PMID:26527054

  12. Impact of Short-Term Treatment with Telmisartan on Cerebral Arterial Remodeling in SHR

    PubMed Central

    Foulquier, Sébastien; Lartaud, Isabelle; Dupuis, François

    2014-01-01

    Background and Purpose Chronic hypertension decreases internal diameter of cerebral arteries and arterioles. We recently showed that short-term treatment with the angiotensin II receptor blocker telmisartan restored baseline internal diameter of small cerebral arterioles in spontaneously hypertensive rats (SHR), via reversal of structural remodeling and inhibition of the angiotensin II vasoconstrictor response. As larger arteries also participate in the regulation of cerebral circulation, we evaluated whether similar short-term treatment affects middle cerebral arteries of SHR. Methods Baseline internal diameters of pressurised middle cerebral arteries from SHR and their respective controls, Wistar Kyoto rats (WKY) and responses to angiotensin II were studied in a small vessel arteriograph. Pressure myogenic curves and passive internal diameters were measured following EDTA deactivation, and elastic modulus from stress-strain relationships. Results Active baseline internal diameter was 23% lower in SHR compared to WKY, passive internal diameter (EDTA) 28% lower and elastic modulus unchanged. Pressure myogenic curves were shifted to higher pressure values in SHR. Telmisartan lowered blood pressure but had no effect on baseline internal diameter nor on structural remodeling (passive internal diameter and elastic modulus remained unchanged compared to SHR). Telmisartan shifted the pressure myogenic curve to lower pressure values than SHR. Conclusion In the middle cerebral arteries of SHR, short-term treatment with telmisartan had no effect on structural remodeling and did not restore baseline internal diameter, but allowed myogenic tone to adapt towards lower pressure values. PMID:25333878

  13. Short-term adaptation to a simple motor task: a physiological process preserved in multiple sclerosis.

    PubMed

    Mancini, L; Ciccarelli, O; Manfredonia, F; Thornton, J S; Agosta, F; Barkhof, F; Beckmann, C; De Stefano, N; Enzinger, C; Fazekas, F; Filippi, M; Gass, A; Hirsch, J G; Johansen-Berg, H; Kappos, L; Korteweg, T; Manson, S C; Marino, S; Matthews, P M; Montalban, X; Palace, J; Polman, C; Rocca, M; Ropele, S; Rovira, A; Wegner, C; Friston, K; Thompson, A; Yousry, T

    2009-04-01

    Short-term adaptation indicates the attenuation of the functional MRI (fMRI) response during repeated task execution. It is considered to be a physiological process, but it is unknown whether short-term adaptation changes significantly in patients with brain disorders, such as multiple sclerosis (MS). In order to investigate short-term adaptation during a repeated right-hand tapping task in both controls and in patients with MS, we analyzed the fMRI data collected in a large cohort of controls and MS patients who were recruited into a multi-centre European fMRI study. Four fMRI runs were acquired for each of the 55 controls and 56 MS patients at baseline and 33 controls and 26 MS patients at 1-year follow-up. The externally cued (1 Hz) right hand tapping movement was limited to 3 cm amplitude by using at all sites (7 at baseline and 6 at follow-up) identically manufactured wooden frames. No significant differences in cerebral activation were found between sites. Furthermore, our results showed linear response adaptation (i.e. reduced activation) from run 1 to run 4 (over a 25 minute period) in the primary motor area (contralateral more than ipsilateral), in the supplementary motor area and in the primary sensory cortex, sensory-motor cortex and cerebellum, bilaterally. This linear activation decay was the same in both control and patient groups, did not change between baseline and 1-year follow-up and was not influenced by the modest disease progression observed over 1 year. These findings confirm that the short-term adaptation to a simple motor task is a physiological process which is preserved in MS.

  14. Emergency presentation of cancer and short-term mortality

    PubMed Central

    McPhail, S; Elliss-Brookes, L; Shelton, J; Ives, A; Greenslade, M; Vernon, S; Morris, E J A; Richards, M

    2013-01-01

    Background: The short-term survival following a cancer diagnosis in England is lower than that in comparable countries, with the difference in excess mortality primarily occurring in the months immediately after diagnosis. We assess the impact of emergency presentation (EP) on the excess mortality in England over the course of the year following diagnosis. Methods: All colorectal and cervical cancers presenting in England and all breast, lung, and prostate cancers in the East of England in 2006–2008 are included. The variation in the likelihood of EP with age, stage, sex, co-morbidity, and income deprivation is modelled. The excess mortality over 0–1, 1–3, 3–6, and 6–12 months after diagnosis and its dependence on these case-mix factors and presentation route is then examined. Results: More advanced stage and older age are predictive of EP, as to a lesser extent are co-morbidity, higher income deprivation, and female sex. In the first month after diagnosis, we observe case-mix-adjusted excess mortality rate ratios of 7.5 (cervical), 5.9 (colorectal), 11.7 (breast ), 4.0 (lung), and 20.8 (prostate) for EP compared with non-EP. Conclusion: Individuals who present as an emergency experience high short-term mortality in all cancer types examined compared with non-EPs. This is partly a case-mix effect but EP remains predictive of short-term mortality even when age, stage, and co-morbidity are accounted for. PMID:24045658

  15. Short-term energy outlook: Quarterly projections, second quarter 1997

    SciTech Connect

    1997-04-01

    The Energy Information Administration (EIA) prepares quarterly short-term energy supply, demand, and price projections for publication in January, April, July, and October in the Outlook. The forecast period for this issue of the Outlook extends from the second quarter of 1997 through the fourth quarter of 1998. Values for the first quarter of 1997, however, are preliminary EIA estimates (for example, some monthly values for petroleum supply and disposition are derived in part from weekly data reported in EIA`s Weekly Petroleum Status Report) or are calculated from model simulations that use the latest exogenous information available (for example, electricity sales and generation are simulated by using actual weather data). The historical energy data, compiled in the second quarter 1997 version of the Short-Term Integrated Forecasting System (STIFS) database, are mostly EIA data regularly published in the Monthly Energy Review, Petroleum Supply Monthly, and other EIA publications. Minor discrepancies between the data in these publications and the historical data in this Outlook are due to independent rounding. The STIFS database is archived quarterly and is available from the National Technical Information Service. The STIFS model is driven principally by three sets of assumptions or inputs: estimates of key macroeconomic variables, world oil price assumptions, and assumptions about the severity of weather. Macroeconomic estimates are produced by DRI/McGraw-Hill but are adjusted by EIA to reflect EIA assumptions about the world price of crude oil, energy product prices, and other assumptions which may affect the macroeconomic outlook. By varying the assumptions, alternative cases are produced by using the Short-Term Integrated Forecasting System (STIFS). 34 figs., 19 tabs.

  16. Short-term energy outlook. Quarterly projections, first quarter 1996

    SciTech Connect

    1996-02-01

    The Energy Information Administration (EIA) prepares quarterly, short-term energy supply, demand, and price projections for publication in February, May, August, and November in the Outlook. The forecast period for this issue of the Outlook extends from the first quarter of 1996 through the fourth quarter of 1997. Values for the fourth quarter of 1995, however, are preliminary EIA estimates (for example, some monthly values for petroleum supply and disposition are derived in part from weekly data reported in the Weekly Petroleum Status Report) or are calculated from model simulations using the latest exogenous information available (for example, electricity sales and generation are simulated using actual weather data). The historical energy data, compiled into the first quarter 1996 version of the Short-Term Integrated Forecasting System (STIFS) database, are mostly EIA data regularly published in the Monthly Energy Review, Petroleum Supply Monthly, and other EIA publications. Minor discrepancies between the data in these publications and the historical data in this Outlook are due to independent rounding. The STIFS database is archived quarterly and is available from the National Technical Information Service. The cases are produced using the Short-Term Integrated Forecasting System (STIFS). The STIFS model is driven principally by three sets of assumptions or inputs: estimates of key macroeconomic variables, world oil price assumptions, and assumptions about the severity of weather. Macroeconomic estimates are produced by DRI/McGraw-Hill but are adjusted by EIA to reflect EIA assumptions about the world price of crude oil, energy product prices, and other assumptions which may affect the macroeconomic outlook.

  17. Power system very short-term load prediction

    SciTech Connect

    Trudnowski, D.J.; Johnson, J.M.; Whitney, P.

    1997-02-01

    A fundamental objective of a power-system operating and control scheme is to maintain a match between the system`s overall real-power load and generation. To accurately maintain this match, modern energy management systems require estimates of the future total system load. Several strategies and tools are available for estimating system load. Nearly all of these estimate the future load in 1-hour steps over several hours (or time frames very close to this). While hourly load estimates are very useful for many operation and control decisions, more accurate estimates at closer intervals would also be valuable. This is especially true for emerging Area Generation Control (AGC) strategies such as look-ahead AGC. For these short-term estimation applications, future load estimates out to several minutes at intervals of 1 to 5 minutes are required. The currently emerging operation and control strategies being developed by the BPA are dependent on accurate very short-term load estimates. To meet this need, the BPA commissioned the Pacific Northwest National Laboratory (PNNL) and Montana Tech (an affiliate of the University of Montana) to develop an accurate load prediction algorithm and computer codes that automatically update and can reliably perform in a closed-loop controller for the BPA system. The requirements include accurate load estimation in 5-minute steps out to 2 hours. This report presents the results of this effort and includes: a methodology and algorithms for short-term load prediction that incorporates information from a general hourly forecaster; specific algorithm parameters for implementing the predictor in the BPA system; performance and sensitivity studies of the algorithms on BPA-supplied data; an algorithm for filtering power system load samples as a precursor to inputting into the predictor; and FORTRAN 77 subroutines for implementing the algorithms.

  18. Improving digit span assessment of short-term verbal memory.

    PubMed

    Woods, David L; Kishiyamaa, Mark M; Lund, E William; Herron, Timothy J; Edwards, Ben; Poliva, Oren; Hink, Robert F; Reed, Bruce

    2011-01-01

    We measured digit span (DS) in two experiments that used computerized presentation of randomized auditory digits with performance-adapted list length adjustment. A new mean span (MS) metric of DS was developed that showed reduced variance, improved test-retest reliability, and higher correlations with the results of other neuropsychological test results when compared to traditional DS measures. The MS metric also enhanced the sensitivity of forward versus backward span comparisons, enabled the development of normative performance criteria with subdigit precision, and elucidated changes in DS performance with age and education level. Computerized stimulus delivery and improved scoring metrics significantly enhance the precision of DS assessments of short-term verbal memory.

  19. Short-term energy outlook. Volume 2. Methodology

    NASA Astrophysics Data System (ADS)

    1983-05-01

    Recent changes in forecasting methodology for nonutility distillate fuel oil demand and for the near-term petroleum forecasts are discussed. The accuracy of previous short-term forecasts of most of the major energy sources published in the last 13 issues of the Outlook is evaluated. Macroeconomic and weather assumptions are included in this evaluation. Energy forecasts for 1983 are compared. Structural change in US petroleum consumption, the use of appropriate weather data in energy demand modeling, and petroleum inventories, imports, and refinery runs are discussed.

  20. Short-term memory load and pronunciation rate

    NASA Technical Reports Server (NTRS)

    Schweickert, Richard; Hayt, Cathrin

    1988-01-01

    In a test of short-term memory recall, two subjects attempted to recall various lists. For unpracticed subjects, the time it took to read the list is a better predictor of immediate recall than the number of items on the list. For practiced subjects, the two predictors do about equally well. If the items that must be recalled are unfamiliar, it is advantageous to keep the items short to pronounce. On the other hand, if the same items will be encountered over and over again, it is advantageous to make them distinctive, even at the cost of adding to the number of syllables.

  1. Short-term energy outlook, quarterly projections, second quarter 1998

    SciTech Connect

    1998-04-01

    The Energy Information Administration (EIA) prepares quarterly short-term energy supply, demand, and price projections. The details of these projections, as well as monthly updates, are available on the Internet at: www.eia.doe.gov/emeu/steo/pub/contents.html. The paper discusses outlook assumptions; US energy prices; world oil supply and the oil production cutback agreement of March 1998; international oil demand and supply; world oil stocks, capacity, and net trade; US oil demand and supply; US natural gas demand and supply; US coal demand and supply; US electricity demand and supply; US renewable energy demand; and US energy demand and supply sensitivities. 29 figs., 19 tabs.

  2. Short-term muscle power during growth and maturation.

    PubMed

    Van Praagh, Emmanuel; Doré, Eric

    2002-01-01

    During growth and maturation, the study of very brief high-intensity exercise has not received the same attention from researchers as, for instance, aerobic function. In anaerobic tasks or sports events such as sprint cycling, jumping or running, the children's performance is distinctly lower than that of adults. This partly reflects children's lesser ability to generate mechanical energy from chemical energy sources during short-term intensive activity. For many years, various attempts have been made to quantify the anaerobic energy yield in maximal-intensity exercise, but many assumptions have had to be made with respect to mechanical efficiency, lactate turnover, dilution space for lactate, and so on. During childhood and adolescence, direct measurements of the rate or capacity of anaerobic pathways for energy turnover presents several ethical and methodological difficulties. Thus, rather than measure energy supply, paediatric exercise scientists have concentrated on measuring short-term muscle power (STMP) by means of standardised tests. Previously, investigators have used various protocols such as short-term cycling power tests, vertical jump tests or running tests. Cycling ergometer tests are the most common. There is, however, no ideal test, and so it is important to acknowledge the limitations of each test. Progress has been made in assessing instantaneous cycling STMP from a single exercise bout. Several investigators have reported STMP increases with age and have suggested that late pubertal period may accentuate anaerobic glycolysis. Mass-related STMP was shown to increase dramatically during childhood and adolescence, whereas the corresponding increase in peak blood lactate was considerably lower. The latter results support the hypothesis that the difference observed between children and adolescents during STMP testing is more related to neuromuscular factors, hormonal factors and improved motor coordination, rather than being an indicator of reduced

  3. MHz gravitational waves from short-term anisotropic inflation

    SciTech Connect

    Ito, Asuka; Soda, Jiro

    2016-04-18

    We reveal the universality of short-term anisotropic inflation. As a demonstration, we study inflation with an exponential type gauge kinetic function which is ubiquitous in models obtained by dimensional reduction from higher dimensional fundamental theory. It turns out that an anisotropic inflation universally takes place in the later stage of conventional inflation. Remarkably, we find that primordial gravitational waves with a peak amplitude around 10{sup −26}∼10{sup −27} are copiously produced in high-frequency bands 10 MHz∼100 MHz. If we could detect such gravitational waves in future, we would be able to probe higher dimensional fundamental theory.

  4. Short-term bioconcentration studies of Np in freshwater biota

    SciTech Connect

    Poston, T.M.; Klopfer, D.C.; Simmons, M.A. )

    1990-12-01

    Short-term laboratory exposures were conducted to determine the potential accumulation of Np in aquatic organisms. Concentration factors were highest in green algae. Daphnia magna, a filter-feeding crustacean, accumulated Np at levels one order of magnitude greater than the amphipod Gammarus sp., an omnivorous substrate feeder. Accumulation of Np in juvenile rainbow trout (Oncorhynchus mykiss) was highest in carcass (generally greater than 78% of the total body burden) and lowest in fillets. Recommended concentration factors for Np, based on fresh weight, were 300 for green algae, 100 for filter-feeding invertebrates, for nonfilter-feeding invertebrates, 10 for whole fish, and one for fish flesh.

  5. Overwriting and intrusion in short-term memory.

    PubMed

    Bancroft, Tyler D; Jones, Jeffery A; Ensor, Tyler M; Hockley, William E; Servos, Philip

    2016-04-01

    Studies of interference in working and short-term memory suggest that irrelevant information may overwrite the contents of memory or intrude into memory. While some previous studies have reported greater interference when irrelevant information is similar to the contents of memory than when it is dissimilar, other studies have reported greater interference for dissimilar distractors than for similar distractors. In the present study, we find the latter effect in a paradigm that uses auditory tones as stimuli. We suggest that the effects of distractor similarity to memory contents are mediated by the type of information held in memory, particularly the complexity or simplicity of information.

  6. Deformability of expanded polystyrene under short-term compression

    NASA Astrophysics Data System (ADS)

    Gnip, I. J.; Vaitkus, S. I.; Kersulis, V. I.; Veyelis, S. A.

    2007-09-01

    The results obtained in an experimental investigation of deformability of expanded polystyrene (EPS) under short-term compression are presented. The density of EPS varied from 13 to 28 kg/m3. The method of design of experiments was used to determine the elastic modulus and the ultimate strain (corresponding to the end of quasi-linear deformability) under compression stresses operating perpendicularly and parallel to the faces of EPS products. A graphical interpretation of the models is also presented. Based on the experimental data obtained, it was concluded that the expanded polystyrene was homogeneous in mutually perpendicular planes with respect to its deformability in compression.

  7. MHz gravitational waves from short-term anisotropic inflation

    NASA Astrophysics Data System (ADS)

    Ito, Asuka; Soda, Jiro

    2016-04-01

    We reveal the universality of short-term anisotropic inflation. As a demonstration, we study inflation with an exponential type gauge kinetic function which is ubiquitous in models obtained by dimensional reduction from higher dimensional fundamental theory. It turns out that an anisotropic inflation universally takes place in the later stage of conventional inflation. Remarkably, we find that primordial gravitational waves with a peak amplitude around 10-26~ 10-27 are copiously produced in high-frequency bands 10 MHz~100 MHz. If we could detect such gravitational waves in future, we would be able to probe higher dimensional fundamental theory.

  8. Short-Term Plasticity of a Thalamocortical Pathway Dynamically Modulated by Behavioral State

    NASA Astrophysics Data System (ADS)

    Castro-Alamancos, Manuel A.; Connors, Barry W.

    1996-04-01

    The neocortex receives information about the environment and the rest of the brain through pathways from the thalamus. These pathways have frequency-dependent properties that can strongly influence their effect on the neocortex. In 1943 Morison and Dempsey described "augmenting responses," a form of short-term plasticity in some thalamocortical pathways that is triggered by 8- to 15-hertz activation. Results from anesthetized rats showed that the augmenting response is initiated by pyramidal cells in layer V. The augmenting response was also observed in awake, unrestrained animals and was found to be dynamically modulated by their behavioral state.

  9. Short-Term Monocular Deprivation Enhances Physiological Pupillary Oscillations

    PubMed Central

    Binda, Paola

    2017-01-01

    Short-term monocular deprivation alters visual perception in adult humans, increasing the dominance of the deprived eye, for example, as measured with binocular rivalry. This form of plasticity may depend upon the inhibition/excitation balance in the visual cortex. Recent work suggests that cortical excitability is reliably tracked by dilations and constrictions of the pupils of the eyes. Here, we ask whether monocular deprivation produces a systematic change of pupil behavior, as measured at rest, that is independent of the change of visual perception. During periods of minimal sensory stimulation (in the dark) and task requirements (minimizing body and gaze movements), slow pupil oscillations, “hippus,” spontaneously appear. We find that hippus amplitude increases after monocular deprivation, with larger hippus changes in participants showing larger ocular dominance changes (measured by binocular rivalry). This tight correlation suggests that a single latent variable explains both the change of ocular dominance and hippus. We speculate that the neurotransmitter norepinephrine may be implicated in this phenomenon, given its important role in both plasticity and pupil control. On the practical side, our results indicate that measuring the pupil hippus (a simple and short procedure) provides a sensitive index of the change of ocular dominance induced by short-term monocular deprivation, hence a proxy for plasticity. PMID:28163935

  10. Short-Term Test Results: Multifamily Home Energy Efficiency Retrofit

    SciTech Connect

    Lyons, J.

    2013-01-01

    Multifamily deep energy retrofits (DERs) represent great potential for energy savings, while also providing valuable insights on research-generated efficiency measures, cost-effectiveness metrics, and risk factor strategies for the multifamily housing industry. The Bay Ridge project is comprised of a base scope retrofit with a goal of achieving 30% savings (relative to pre-retrofit), and a DER scope with a goal of 50% savings (relative to pre-retrofit). The base scope has been applied to the entire complex, except for one 12-unit building which underwent the DER scope. Findings from the implementation, commissioning, and short-term testing at Bay Ridge include air infiltration reductions of greater than 60% in the DER building; a hybrid heat pump system with a Savings to Investment Ratio (SIR) > 1 (relative to a high efficiency furnace) which also provides the resident with added incentive for energy savings; and duct leakage reductions of > 60% using an aerosolized duct sealing approach. Despite being a moderate rehab instead of a gut rehab, the Bay Ridge DER is currently projected to achieve energy savings ≥ 50% compared to pre-retrofit, and the short-term testing supports this estimate.

  11. Short-Term Lifestyle Strategies for Sustaining Cognitive Status.

    PubMed

    Howard, Elizabeth P; Morris, John N; Steel, Knight; Strout, Kelley A; Fries, Brant E; Moore, Alice; Garms-Homolová, Vjenka

    2016-01-01

    Cognitive decline impacts older adults, particularly their independence. The goal of this project was to increase understanding of how short-term, everyday lifestyle options, including physical activity, help an older adult sustain cognitive independence. Using a secondary analysis of lifestyle choices, we drew on a dataset of 4,620 community-dwelling elders in the US, assessed at baseline and one year later using 2 valid and reliable tools, the interRAI Community Health Assessment and the interRAI Wellness tool. Decline or no decline on the Cognitive Performance Scale was the dependent variable. We examined sustaining one's status on this measure over a one-year period in relation to key dimensions of wellness through intellectual, physical, emotional, social, and spiritual variables. Engaging in physical activity, formal exercise, and specific recreational activities had a favorable effect on short-term cognitive decline. Involvement with computers, crossword puzzles, handicrafts, and formal education courses also were protective factors. The physical and intellectual domains of wellness are prominent aspects in protection from cognitive decline. Inherent in these two domains are mutable factors suitable for targeted efforts to promote older adult health and well-being.

  12. Robust Short-Term Memory without Synaptic Learning

    PubMed Central

    Johnson, Samuel; Marro, J.; Torres, Joaquín J.

    2013-01-01

    Short-term memory in the brain cannot in general be explained the way long-term memory can – as a gradual modification of synaptic weights – since it takes place too quickly. Theories based on some form of cellular bistability, however, do not seem able to account for the fact that noisy neurons can collectively store information in a robust manner. We show how a sufficiently clustered network of simple model neurons can be instantly induced into metastable states capable of retaining information for a short time (a few seconds). The mechanism is robust to different network topologies and kinds of neural model. This could constitute a viable means available to the brain for sensory and/or short-term memory with no need of synaptic learning. Relevant phenomena described by neurobiology and psychology, such as local synchronization of synaptic inputs and power-law statistics of forgetting avalanches, emerge naturally from this mechanism, and we suggest possible experiments to test its viability in more biological settings. PMID:23349664

  13. Chlorella sorokiniana Extract Improves Short-Term Memory in Rats.

    PubMed

    Morgese, Maria Grazia; Mhillaj, Emanuela; Francavilla, Matteo; Bove, Maria; Morgano, Lucia; Tucci, Paolo; Trabace, Luigia; Schiavone, Stefania

    2016-09-29

    Increasing evidence shows that eukaryotic microalgae and, in particular, the green microalga Chlorella, can be used as natural sources to obtain a whole variety of compounds, such as omega (ω)-3 and ω-6 polyunsatured fatty acids (PUFAs). Although either beneficial or toxic effects of Chlorella sorokiniana have been mainly attributed to its specific ω-3 and ω-6 PUFAs content, the underlying molecular pathways remain to be elucidated yet. Here, we investigate the effects of an acute oral administration of a lipid extract of Chlorella sorokiniana, containing mainly ω-3 and ω-6 PUFAs, on cognitive, emotional and social behaviour in rats, analysing possible underlying neurochemical alterations. Our results showed improved short-term memory in Chlorella sorokiniana-treated rats compared to controls, without any differences in exploratory performance, locomotor activity, anxiety profile and depressive-like behaviour. On the other hand, while the social behaviour of Chlorella sorokiniana-treated animals was significantly decreased, no effects on aggressivity were observed. Neurochemical investigations showed region-specific effects, consisting in an elevation of noradrenaline (NA) and serotonin (5-HT) content in hippocampus, but not in the prefrontal cortex and striatum. In conclusion, our results point towards a beneficial effect of Chlorella sorokiniana extract on short-term memory, but also highlight the need of caution in the use of this natural supplement due to its possible masked toxic effects.

  14. Short-term energy outlook. Quarterly projections, third quarter 1996

    SciTech Connect

    1996-07-01

    The Energy Information Administration (EIA) prepares quarterly, short-term energy supply, demand, and price projections for publication in January, April, July, and October in the Outlook. The forecast period for this issue of the Outlook extends from the third quarter of 1996 through the fourth quarter of 1997. Values for the second quarter of 1996, however, are preliminary EIA estimates (for example, some monthly values for petroleum supply and disposition are derived in part from weekly data reported in the Weekly Petroleum Status Report) or are calculated from model simulations using the latest exogenous information available (for example, electricity sales and generation are simulated using actual weather data). The historical energy data, compiled in the third quarter 1996 version of the Short-Term Integrated Forecasting System (STIFS) database, are mostly EIA data regularly published in the Monthly energy Review, Petroleum Supply Monthly, and other EIA publications. Minor discrepancies between the data in these publications and the historical data in this Outlook are due to independent rounding. The STIFS database is archived quarterly and is available from the National Technical Information Service.

  15. Short-Term Monocular Deprivation Enhances Physiological Pupillary Oscillations.

    PubMed

    Binda, Paola; Lunghi, Claudia

    2017-01-01

    Short-term monocular deprivation alters visual perception in adult humans, increasing the dominance of the deprived eye, for example, as measured with binocular rivalry. This form of plasticity may depend upon the inhibition/excitation balance in the visual cortex. Recent work suggests that cortical excitability is reliably tracked by dilations and constrictions of the pupils of the eyes. Here, we ask whether monocular deprivation produces a systematic change of pupil behavior, as measured at rest, that is independent of the change of visual perception. During periods of minimal sensory stimulation (in the dark) and task requirements (minimizing body and gaze movements), slow pupil oscillations, "hippus," spontaneously appear. We find that hippus amplitude increases after monocular deprivation, with larger hippus changes in participants showing larger ocular dominance changes (measured by binocular rivalry). This tight correlation suggests that a single latent variable explains both the change of ocular dominance and hippus. We speculate that the neurotransmitter norepinephrine may be implicated in this phenomenon, given its important role in both plasticity and pupil control. On the practical side, our results indicate that measuring the pupil hippus (a simple and short procedure) provides a sensitive index of the change of ocular dominance induced by short-term monocular deprivation, hence a proxy for plasticity.

  16. Short term dynamics of the debris-covered Miage Glacier

    NASA Astrophysics Data System (ADS)

    Fyffe, Catriona; Brock, Ben; Kirkbride, Martin; Mair, Doug; Smiraglia, Claudio; Diolaiuti, Guglielmina

    2016-04-01

    Due to the often inaccessible nature of debris-covered glaciers, studies of their dynamics tend to be restricted to those using remotely sensed data. This paper presents data on the short-term glacier dynamics of the debris-covered Miage Glacier, Western Italian Alps. The glacier velocity was calculated from repeat occupation of up to 22 points using a differential GPS system over two melt seasons. Meteorological, hydrological and water chemistry data were collected over the same time periods, and the nature of the hydrological system was studied using dye tracing, to allow the short term variations in glacier dynamics to be understood in terms of the likely glacial drainage system and its evolution. The highest glacier velocities and the greatest velocity variability was found near to where a cluster of moulins enter the glacier, close to the limit of continuous debris cover. The melt from the clean and dirty ice occasionally led to inputs overcoming the channelized system (both in spring and mid-summer), leading to increased velocities. On the debris-covered lower glacier however velocities were lower and less variable, and significant speed-up was confined to a period when subglacial water was thought to have been transferred subglacially from higher upglacier. The subdued sub-debris melt signal is thought to be the cause of the reduced velocity variability, in spite of the hydrological system beneath this part of the glacier remaining inefficient.

  17. Cigarette smoking and short-term addiction treatment outcome.

    PubMed

    Harrell, P T; Montoya, I D; Preston, K L; Juliano, L M; Gorelick, D A

    2011-06-01

    Cigarette smoking is common among patients in cocaine and opioid dependence treatment, and may influence treatment outcome. We addressed this issue in a secondary analysis of data from an outpatient clinical trial of buprenorphine treatment for concurrent cocaine and opioid dependence (13 weeks, N=200). The association between cigarette smoking (lifetime cigarette smoking status, number of cigarettes smoked per day prior to study entry) and short-term treatment outcome (% of urine samples positive for cocaine or opioids, treatment retention) was evaluated with analysis of covariance, bivariate correlations, and multivariate linear regression. Nicotine-dependent smokers (66% of participants) had a significantly higher percentage of cocaine-positive urine samples than non-smokers (12% of participants) (76% vs. 62%), but did not differ in percentage of opioid-positive urine samples or treatment retention. Number of cigarettes smoked per day at baseline was positively associated with percentage of cocaine-positive urine samples, even after controlling for baseline sociodemographic and drug use characteristics, but was not significantly associated with percentage of opioid-positive urine samples or treatment retention. These results suggest that cigarette smoking is associated with poorer short-term outcome of outpatient treatment for cocaine dependence, but perhaps not of concurrent opioid dependence, and support the importance of offering smoking cessation treatment to cocaine-dependent patients.

  18. Short-term extractability of sulfadiazine after application to soils.

    PubMed

    Müller, Tanja; Rosendahl, Ingrid; Focks, Andreas; Siemens, Jan; Klasmeier, Jörg; Matthies, Michael

    2013-01-01

    The long-term environmental fate of the veterinary antibiotic sulfadiazine (SDZ) in soils is determined by a reversible sequestration into a residual fraction and an irreversible formation of non-extractable residues (NER), which can be described as first-order rate processes. However, the concentration dynamics of the resulting fractions of SDZ in soil show an unexplained rapid reduction of extractability during the first 24 h. We therefore investigated the short-term extractability of SDZ in two different soils under different SDZ application procedures over 24 h: with and without manure, for air-dried and for moist soils. In all batches, we observed an instantaneous loss of extractability on a time scale of minutes as well as kinetically determined sequestration and NER formation over 24 h. Data evaluation with a simple kinetic model led to the conclusion that application with manure accelerated the short-term formation of NER, whereas sequestration was very similar for all batches.

  19. Short-Term Effects of Hydrokinesiotherapy in Hospitalized Preterm Newborns

    PubMed Central

    de Oliveira Tobinaga, Welcy Cassiano; Abelenda, Vera Lucia Barros; de Sá, Paula Morisco

    2016-01-01

    Background. In the neonatal intensive care unit (NICU) environment, preterm newborns are subject to environmental stress and numerous painful interventions. It is known that hydrokinesiotherapy promotes comfort and reduces stress because of the physiological properties of water. Objective. To evaluate the short-term effects of hydrokinesiotherapy on reducing stress in preterm newborns admitted to the NICU. Materials and Methods. Fifteen preterm newborns underwent salivary cortisol measurement, pain evaluation using the Neonatal Infant Pain Scale (NIPS), and heart rate, respiratory rate, and peripheral oxygen saturation measurements before and after the application of hydrokinesiotherapy. Results. The mean gestational age of the newborns was 34.2 ± 1.66 weeks, and the mean weight was 1823.3 ± 437.4 g. Immediately after application of hydrokinesiotherapy, a significant reduction was observed in salivary cortisol (p = 0.004), heart rate (p = 0.003), and respiratory rate (p = 0.004) and a significant increase was observed in peripheral oxygen saturation (p = 0.002). However, no significant difference was observed in the NIPS score (p > 0.05). Conclusion. In the present study, neonatal hydrotherapy promoted short-term relief from feelings of stress. Neonatal hydrokinesiotherapy may be a therapeutic alternative. However, this therapy needs to be studied in randomized, crossover, and blinded trials. This trial is registered with NCT02707731. PMID:27672453

  20. Short-Term Lifestyle Strategies for Sustaining Cognitive Status

    PubMed Central

    Morris, John N.; Steel, Knight; Strout, Kelley A.; Fries, Brant E.; Moore, Alice; Garms-Homolová, Vjenka

    2016-01-01

    Cognitive decline impacts older adults, particularly their independence. The goal of this project was to increase understanding of how short-term, everyday lifestyle options, including physical activity, help an older adult sustain cognitive independence. Using a secondary analysis of lifestyle choices, we drew on a dataset of 4,620 community-dwelling elders in the US, assessed at baseline and one year later using 2 valid and reliable tools, the interRAI Community Health Assessment and the interRAI Wellness tool. Decline or no decline on the Cognitive Performance Scale was the dependent variable. We examined sustaining one's status on this measure over a one-year period in relation to key dimensions of wellness through intellectual, physical, emotional, social, and spiritual variables. Engaging in physical activity, formal exercise, and specific recreational activities had a favorable effect on short-term cognitive decline. Involvement with computers, crossword puzzles, handicrafts, and formal education courses also were protective factors. The physical and intellectual domains of wellness are prominent aspects in protection from cognitive decline. Inherent in these two domains are mutable factors suitable for targeted efforts to promote older adult health and well-being. PMID:27891520

  1. Prediction of short-term distributions of load extremes of offshore wind turbines

    NASA Astrophysics Data System (ADS)

    Wang, Ying-guang

    2016-12-01

    This paper proposes a new methodology to select an optimal threshold level to be used in the peak over threshold (POT) method for the prediction of short-term distributions of load extremes of offshore wind turbines. Such an optimal threshold level is found based on the estimation of the variance-to-mean ratio for the occurrence of peak values, which characterizes the Poisson assumption. A generalized Pareto distribution is then fitted to the extracted peaks over the optimal threshold level and the distribution parameters are estimated by the method of the maximum spacing estimation. This methodology is applied to estimate the short-term distributions of load extremes of the blade bending moment and the tower base bending moment at the mudline of a monopile-supported 5MW offshore wind turbine as an example. The accuracy of the POT method using the optimal threshold level is shown to be better, in terms of the distribution fitting, than that of the POT methods using empirical threshold levels. The comparisons among the short-term extreme response values predicted by using the POT method with the optimal threshold levels and with the empirical threshold levels and by using direct simulation results further substantiate the validity of the proposed new methodology.

  2. Short-Term Peripheral Auditory Effects of Cranial Irradiation: A Mouse Model

    PubMed Central

    Gasser Rutledge, Krysta L.; Prasad, Kumar G.; Emery, Kara R.; Mikulec, Anthony A.; Varvares, Mark; Gratton, Michael Anne

    2015-01-01

    Objectives Assess post-cranial irradiation short-term threshold shift short-term peripheral auditory histopathology the mouse as an experimental model Methods Adult mice were exposed to single-dose radiation of 10 – 60 Gy. Pre- and post-irradiation (baseline, 2 – 8 days) audiometric brainstem response data were recorded with analysis of cochlear ultrastructure. Results Significant threshold shift occurred at all test frequencies in mice exposed to ≥ 20 Gy at 4 – 6 days post-irradiation. Ultrastructurally in Rosenthal’s canal and the spiral lamina, neuronal density and extracellular matrix decreased dramatically. There was overall preservation of hair cells, stria vascularis, and vasculature. No difference within Gy group was noted in the frequency or severity of pathology along the length of the cochlea. Conclusions The initial impact of radiation in the first week post-exposure focuses on spiral ganglion cell bodies and peripheral projections, resulting in significant threshold shift for irradiation dosages ≥ 20 Gy. This study demonstrates that the mouse is a viable model for study of short-term peripheral auditory effects using single-dose cranial irradiation. Additionally, with access to a precise animal irradiator, the mouse may be used as an experimental model for a fractionated irradiation dosage of 10 Gy, simulating stereotactic therapeutic cranial irradiation. PMID:26085370

  3. Neuronal correlate of pictorial short-term memory in the primate temporal cortexYasushi Miyashita

    NASA Astrophysics Data System (ADS)

    Miyashita, Yasushi; Chang, Han Soo

    1988-01-01

    It has been proposed that visual-memory traces are located in the temporal lobes of the cerebral cortex, as electric stimulation of this area in humans results in recall of imagery1. Lesions in this area also affect recognition of an object after a delay in both humans2,3 and monkeys4-7 indicating a role in short-term memory of images8. Single-unit recordings from the temporal cortex have shown that some neurons continue to fire when one of two or four colours are to be remembered temporarily9. But neuronal responses selective to specific complex objects10-18 , including hands10,13 and faces13,16,17, cease soon after the offset of stimulus presentation10-18. These results led to the question of whether any of these neurons could serve the memory of complex objects. We report here a group of shape-selective neurons in an anterior ventral part of the temporal cortex of monkeys that exhibited sustained activity during the delay period of a visual short-term memory task. The activity was highly selective for the pictorial information to be memorized and was independent of the physical attributes such as size, orientation, colour or position of the object. These observations show that the delay activity represents the short-term memory of the categorized percept of a picture.

  4. Persistent spatial information in the frontal eye field during object-based short-term memory.

    PubMed

    Clark, Kelsey L; Noudoost, Behrad; Moore, Tirin

    2012-08-08

    Spatial attention is known to gate entry into visual short-term memory, and some evidence suggests that spatial signals may also play a role in binding features or protecting object representations during memory maintenance. To examine the persistence of spatial signals during object short-term memory, the activity of neurons in the frontal eye field (FEF) of macaque monkeys was recorded during an object-based delayed match-to-sample task. In this task, monkeys were trained to remember an object image over a brief delay, regardless of the locations of the sample or target presentation. FEF neurons exhibited visual, delay, and target period activity, including selectivity for sample location and target location. Delay period activity represented the sample location throughout the delay, despite the irrelevance of spatial information for successful task completion. Furthermore, neurons continued to encode sample position in a variant of the task in which the matching stimulus never appeared in their response field, confirming that FEF maintains sample location independent of subsequent behavioral relevance. FEF neurons also exhibited target-position-dependent anticipatory activity immediately before target onset, suggesting that monkeys predicted target position within blocks. These results show that FEF neurons maintain spatial information during short-term memory, even when that information is irrelevant for task performance.

  5. Impaired semantic knowledge underlies the reduced verbal short-term storage capacity in Alzheimer's disease.

    PubMed

    Peters, Frédéric; Majerus, Steve; De Baerdemaeker, Julie; Salmon, Eric; Collette, Fabienne

    2009-12-01

    A decrease in verbal short-term memory (STM) capacity is consistently observed in patients with Alzheimer's disease (AD). Although this impairment has been mainly attributed to attentional deficits during encoding and maintenance, the progressive deterioration of semantic knowledge in early stages of AD may also be an important determinant of poor STM performance. The aim of this study was to examine the influence of semantic knowledge on verbal short-term memory storage capacity in normal aging and in AD by exploring the impact of word imageability on STM performance. Sixteen patients suffering from mild AD, 16 healthy elderly subjects and 16 young subjects performed an immediate serial recall task using word lists containing high or low imageability words. All participant groups recalled more high imageability words than low imageability words, but the effect of word imageability on verbal STM was greater in AD patients than in both the young and the elderly control groups. More precisely, AD patients showed a marked decrease in STM performance when presented with lists of low imageability words, whereas recall of high imageability words was relatively well preserved. Furthermore, AD patients displayed an abnormal proportion of phonological errors in the low imageability condition. Overall, these results indicate that the support of semantic knowledge on STM performance was impaired for lists of low imageability words in AD patients. More generally, these findings suggest that the deterioration of semantic knowledge is partly responsible for the poor verbal short-term storage capacity observed in AD.

  6. Neuroleptics ameliorate phencyclidine-induced impairments of short-term memory

    PubMed Central

    Schroeder, Ulrike; Schroeder, Helmut; Schwegler, Herbert; Sabel, Bernhard A

    2000-01-01

    Phencyclidine (PCP), a non-competitive NMDA-receptor antagonist, is able to induce schizophrenia-like symptoms in animals and in humans. It is known that schizophrenic patients have deficits in memory processes. Therefore, it was investigated whether subchronic pulsatile or continuous application of 5.0 mg kg−1 PCP over 5 days induce short-term memory deficits in holeboard learning and the action of two different neuroleptics on this behavioural test. First, an impairment in the holeboard task was described when the animals were tested 24 h after the last application but not after 15 min or 1 h after the last injection. Secondly, the influence of haloperidol and risperidone on the PCP-induced short-term memory changes was tested. The combined application of PCP and risperidone led to a complete antagonism of the short-term deficits, but the combined treatment with haloperidol was accompanied by a partial abolishment of the PCP-induced deficits. PCP led to an upregulation of the glutamate binding sites in striatum and nucleus accumbens whereas the D2 binding sites were reduced in striatum. The D1 binding sites seem to be unchanged. The receptor protein expression of glutamate receptors mGluR1, GluR2, GluR5/7 and NMDAR1 were not modified in response to PCP treatment. The determination of a subpopulation of GABAergic interneurons shows a decrease of the cells within the CA3 of the hippocampal formation. These findings indicate that PCP induced impairments in short term memory can be detected by holeboard learning and may provide an interesting tool for the search of new neuroleptics. PMID:10780995

  7. Chances of short-term cooling trends over Canada for the next decades

    NASA Astrophysics Data System (ADS)

    Grenier, Patrick; de Elia, Ramon; Chaumont, Diane

    2014-05-01

    As climate services continue to develop in Quebec, Canada, an increasing number of requests are made for providing information relevant for the near term. As a response, one approach has been to consider short-term cooling trends as a basis for climate products. This project comprises different aspects: technical steps, knowledge transfer, and societal use. Each step does represent a different challenge. The technical part, i.e. producing probabilistic distributions of short-term temperature trends, involves relatively complex scenario construction methods including bias-related post-processing, and access to wide simulation and observation databases. Calculations are performed on 60 CMIP5-based scenarios on a grid covering Canada during the period 2006-2035, and for 5, 10, 15, 20 and 25-year trend durations. Knowledge transfer implies overcoming misinterpretation, given that probabilistic projections based on simulation ensembles are not perfectly related to real-Earth possible outcomes. Finally, societal use of this information remains the biggest challenge. On the one hand, users clearly state their interest in near-term relevant information, and intuitively it seems clear that short-term cooling trends embedded within the long-term warming path should be considered in adaptation plans, for avoiding over-adaptation. On the other hand, the exact way of incorporating such information within a decision-making process has proven not to be obvious. Irrespective of that, the study and communication of short-term cooling chances is necessary for preventing decision-makers to infer from the eventual occurrence of such a trend that global warming isn't happening. The presentation will discuss the three aspects aforementioned.

  8. Post larval, short-term, colonization patterns: The effect of substratum complexity across subtidal, adjacent, habitats

    NASA Astrophysics Data System (ADS)

    García-Sanz, Sara; Tuya, Fernando; Navarro, Pablo G.; Angulo-Preckler, Carlos; Haroun, Ricardo J.

    2012-10-01

    Benthic habitats are colonized by organisms from the water column and adjacent habitats. There are, however, variations in the 'acceptability' of any habitat to potential colonists. We assessed whether the structural complexity of artificial substrata affected patterns of short-term colonization of post larval faunal assemblages across subtidal habitats within a coastal landscape. Specifically, we tested whether short-term colonization patterns on 3 types of artificial substrata encompassing a range of complexities, including a leaf-like unit, a cushion-shaped leaf-like unit and a cushion-shaped unit, were consistent across 4 adjacent habitats: macroalgal-dominated bottoms, urchin-grazed barrens, seagrass meadows and sandy patches, at Gran Canaria (eastern Atlantic). A total of 16,174 organisms were collected after 4 weeks and 4 taxonomic groups (Crustacea, Chordata, Echinodermata and Mollusca) dominated the assemblage. Despite considerable among-taxa variability being observed in response to habitat effects, the total abundance of colonizers, as well as the abundance of Arthropoda, Chordata and Echinodermata, was affected by the habitat where collectors were deployed, but did not differ among types of collectors. Similarly, the assemblage structure of colonizers was mainly affected by the habitat, but not by the type of collector; habitat contributed to explain most variation in the assemblage structure of the four dominant taxonomic groups (from ca. 5.44-19.23%), and obscured, in all cases, variation explained by the type of collector. As a result, the variation in short-term colonization patterns of faunal assemblages into artificial collectors was mostly affected by variation associated with habitats rather than by differences in the structural complexity of collectors. The largest abundances of colonizers, particularly Echinodermata, were found on sandy patches relative to other habitats, suggesting that the 'availability', rather than any particular attribute

  9. The treatment of anorgasmia: long-term effectiveness of a short-term behavioral group therapy.

    PubMed

    Kuriansky, J B; Sharpe, L; O'Connor, D

    1982-01-01

    A long-term follow-up of 19 women who participated in short-term group therapy for anorgasmia using masturbation and assertiveness training showed that the majority of women maintained treatment gains and progressed further in orgasm response and other aspects of sexual functioning, including assertiveness and liberalness of sexual attitudes. However, several women regressed, and four additional women who dropped out of treatment also improved dramatically in orgasm response, suggesting that other patient characteristics and factors affect apparent treatment outcome. Independent evaluations, standardized assessment scales, long-term, in-person follow-ups and multidimensional assessment are useful in evaluating treatment effectiveness.

  10. Short-term Cost of Suicides in India

    PubMed Central

    Poduri, Gopala Sarma

    2016-01-01

    Background: India is experiencing increasing suicides that have much economic impact. Objective: To calculate the short-term costs of suicide in India. Materials and Methods: All the official data of suicides in India in 2014 formed the base of computation. Both direct and indirect costs were computed basing on market rates and official estimates. Perceived gains were deducted to arrive at the total cost. Results: The contribution of middle age group in the loss was high. Each suicide costs 2.65 L and the total cost of suicide in 2014 amounts to 348842.65 L in the first year. Conclusion: Much suffering and burden on individuals, family, and society can be reduced if adequate treatment facilities for psychiatry patients are made available at affordable rates everywhere. This should be complemented by much needed public education. PMID:28031587

  11. Short-Term Test Results. Multifamily Home Energy Efficiency Retrofit

    SciTech Connect

    Lyons, James

    2013-01-01

    Multifamily deep energy retrofits (DERs) represent great potential for energy savings, while also providing valuable insights on research-generated efficiency measures, cost-effectiveness metrics, and risk factor strategies for the multifamily housing industry. This report describes the Bay Ridge project, a base scope retrofit with a goal of achieving 30% savings (relative to pre-retrofit), and a DER scope with a goal of 50% savings (relative to pre-retrofit). Findings from the short-term testing at Bay Ridge include air infiltration reductions of greater than 60% in the DER building; a hybrid heat pump system with a Savings to Investment Ratio (SIR) > 1 (relative to a high efficiency furnace) which also provides the resident with added incentive for energy savings; and duct leakage reductions of > 60% using an aerosolized duct sealing approach.

  12. Short-Term Planning of Hybrid Power System

    NASA Astrophysics Data System (ADS)

    Knežević, Goran; Baus, Zoran; Nikolovski, Srete

    2016-07-01

    In this paper short-term planning algorithm for hybrid power system consist of different types of cascade hydropower plants (run-of-the river, pumped storage, conventional), thermal power plants (coal-fired power plants, combined cycle gas-fired power plants) and wind farms is presented. The optimization process provides a joint bid of the hybrid system, and thus making the operation schedule of hydro and thermal power plants, the operation condition of pumped-storage hydropower plants with the aim of maximizing profits on day ahead market, according to expected hourly electricity prices, the expected local water inflow in certain hydropower plants, and the expected production of electrical energy from the wind farm, taking into account previously contracted bilateral agreement for electricity generation. Optimization process is formulated as hourly-discretized mixed integer linear optimization problem. Optimization model is applied on the case study in order to show general features of the developed model.

  13. Emulating short-term synaptic dynamics with memristive devices

    PubMed Central

    Berdan, Radu; Vasilaki, Eleni; Khiat, Ali; Indiveri, Giacomo; Serb, Alexandru; Prodromakis, Themistoklis

    2016-01-01

    Neuromorphic architectures offer great promise for achieving computation capacities beyond conventional Von Neumann machines. The essential elements for achieving this vision are highly scalable synaptic mimics that do not undermine biological fidelity. Here we demonstrate that single solid-state TiO2 memristors can exhibit non-associative plasticity phenomena observed in biological synapses, supported by their metastable memory state transition properties. We show that, contrary to conventional uses of solid-state memory, the existence of rate-limiting volatility is a key feature for capturing short-term synaptic dynamics. We also show how the temporal dynamics of our prototypes can be exploited to implement spatio-temporal computation, demonstrating the memristors full potential for building biophysically realistic neural processing systems. PMID:26725838

  14. Short-term Variability of Extinction by Broadband Stellar Photometry

    SciTech Connect

    Musat, I.C.; Ellingson, R.G.

    2005-03-18

    Aerosol optical depth variation over short-term time intervals is determined from broadband observations of stars with a whole sky imager. The main difficulty in such measurements consists of accurately separating the star flux value from the non-stellar diffuse skylight. Using correction method to overcome this difficulty, the monochromatic extinction at the ground due to aerosols is extracted from heterochromatic measurements. A form of closure is achieved by comparison with simultaneous or temporally close measurements with other instruments, and the total error of the method, as a combination of random error of measurements and systematic error of calibration and model, is assessed as being between 2.6 and 3% rms.

  15. Short-term risk forecasts of heavy rainfall.

    PubMed

    Schmid, W; Mecklenburg, S; Joss, J

    2002-01-01

    Methodologies for risk forecasts of severe weather hardly exist on the scale of nowcasting (0-3 hours). Here we discuss short-term risk forecasts of heavy precipitation associated with local thunderstorms. We use COTREC/RainCast: a procedure to extrapolate radar images into the near future. An error density function is defined using the estimated error of location of the extrapolated radar patterns. The radar forecast is folded ("smeared") with the density function, leading to a probability distribution of radar intensities. An algorithm to convert the radar intensities into values of precipitation intensity provides the desired probability (or risk) of heavy rainfall at any position within the considered window in space and time. We discuss, as an example, a flood event from summer 2000.

  16. Astronomical observation tasks short-term scheduling using PDDS algorithm

    NASA Astrophysics Data System (ADS)

    Kornilov, M. V.

    2016-07-01

    A concept of the ground-based optical astronomical observation efficiency is considered in this paper. We believe that a telescope efficiency can be increased by properly allocating observation tasks with respect to the current environment state and probability to obtain the data with required properties under the current conditions. An online observations scheduling is assumed to be an essential part for raising the efficiency. The short-term online scheduling is treated as the discrete optimisation problems which are stated using several abstraction levels. The optimisation problems are solved using the parallel depth-bounded discrepancy search (PDDS) algorithm by Moisan et al. (2014). Some aspects of the algorithm performance are discussed. The presented algorithm is a core of open-source chelyabinsk C++ library which is planned to be used at 2.5 m telescope of Sternberg Astronomical Institute of Lomonosov Moscow State University.

  17. Emulating short-term synaptic dynamics with memristive devices

    NASA Astrophysics Data System (ADS)

    Berdan, Radu; Vasilaki, Eleni; Khiat, Ali; Indiveri, Giacomo; Serb, Alexandru; Prodromakis, Themistoklis

    2016-01-01

    Neuromorphic architectures offer great promise for achieving computation capacities beyond conventional Von Neumann machines. The essential elements for achieving this vision are highly scalable synaptic mimics that do not undermine biological fidelity. Here we demonstrate that single solid-state TiO2 memristors can exhibit non-associative plasticity phenomena observed in biological synapses, supported by their metastable memory state transition properties. We show that, contrary to conventional uses of solid-state memory, the existence of rate-limiting volatility is a key feature for capturing short-term synaptic dynamics. We also show how the temporal dynamics of our prototypes can be exploited to implement spatio-temporal computation, demonstrating the memristors full potential for building biophysically realistic neural processing systems.

  18. Short-Term Outlook for Hydrocarbon Gas Liquids

    EIA Publications

    2016-01-01

    U.S. liquid fuels production increased from 7.43 million barrels per day (b/d) in 2008 to 13.75 million b/d in 2015. However, the Short-Term Energy Outlook (STEO) expects liquid fuels production to decline to 12.99 million b/d in 2017, mainly as a result of prolonged low oil prices. The liquid fuels production forecast reflects a 1.24 million b/d decline in crude oil production by 2017 that is partially offset by a 450,000 b/d increase in the production of hydrocarbon gas liquids (HGL)—a group of products including ethane, propane, butane (normal and isobutane), natural gasoline, and refinery olefins. This analysis will discuss the outlook for each of these four HGL streams and related infrastructure projects through 2017.

  19. The effects of short-term hypergravity on Caenorhabditis elegans

    NASA Astrophysics Data System (ADS)

    Saldanha, Jenifer N.; Pandey, Santosh; Powell-Coffman, Jo Anne

    2016-08-01

    As we seek to recognize the opportunities of advanced aerospace technologies and spaceflight, it is increasingly important to understand the impacts of hypergravity, defined as gravitational forces greater than those present on the earth's surface. The nematode Caenorhabditis elegans has been established as a powerful model to study the effects of altered gravity regimens and has displayed remarkable resilience to space travel. In this study, we investigate the effects of short-term and defined hypergravity exposure on C. elegans motility, brood size, pharyngeal pumping rates, and lifespan. The results from this study advance our understanding of the effects of shorter durations of exposure to increased gravitational forces on C. elegans, and also contribute to the growing body of literature on the impacts of altered gravity regimens on earth's life forms.

  20. Human short-term spatial memory: precision predicts capacity.

    PubMed

    Banta Lavenex, Pamela; Boujon, Valérie; Ndarugendamwo, Angélique; Lavenex, Pierre

    2015-03-01

    Here, we aimed to determine the capacity of human short-term memory for allocentric spatial information in a real-world setting. Young adults were tested on their ability to learn, on a trial-unique basis, and remember over a 1-min interval the location(s) of 1, 3, 5, or 7 illuminating pads, among 23 pads distributed in a 4m×4m arena surrounded by curtains on three sides. Participants had to walk to and touch the pads with their foot to illuminate the goal locations. In contrast to the predictions from classical slot models of working memory capacity limited to a fixed number of items, i.e., Miller's magical number 7 or Cowan's magical number 4, we found that the number of visited locations to find the goals was consistently about 1.6 times the number of goals, whereas the number of correct choices before erring and the number of errorless trials varied with memory load even when memory load was below the hypothetical memory capacity. In contrast to resource models of visual working memory, we found no evidence that memory resources were evenly distributed among unlimited numbers of items to be remembered. Instead, we found that memory for even one individual location was imprecise, and that memory performance for one location could be used to predict memory performance for multiple locations. Our findings are consistent with a theoretical model suggesting that the precision of the memory for individual locations might determine the capacity of human short-term memory for spatial information.

  1. Assessment of peak power and short-term work capacity.

    PubMed

    MacIntosh, Brian R; Rishaug, Peter; Svedahl, Krista

    2003-02-01

    The purpose of this study was to evaluate conditions for conducting a 30 s Wingate test such as load selection, and the method of starting the test (stationary or flying start). Nine male and four female athletes volunteered to be tested on four laboratory visits. Tests were performed on a modified Monark cycle ergometer (Varberg, Sweden) equipped with force transducers on the friction belt and an optical encoder for velocity measurement. Power was calculated with the moment of inertia (I) of the flywheel taken into consideration. One laboratory visit was used to determine individualized optimal resistance conditions. The other three visits were for performance of one of three Wingate tests: a flying start with 0.834 N x kg(-1) [85 g x kg(-1) body weight (BW)] resistance (FLY-0.8); a stationary start with 0.834 N x kg(-1) BW resistance (ST-0.8), or a stationary start with optimal resistance (ST-OPT). FLY-0.8 gave a lower (P<0.05) value for short-term work capacity [19,986 (827) J] than either ST-OPT [23,014 (1,167) J] or ST-0.8 [22,321 (1075) J]. Peak power output per pedal revolution was lower ( P<0.005) for FLY-0.8 [833 (40) W] than for either ST-0.8 [974 (57) W] or ST-OPT [989 (61) W]. The results of this study demonstrate that higher values for peak power and short-term work capacity are obtained with a test from a stationary start. It is apparently not necessary to use an individualized optimal resistance when I is considered in a Wingate test initiated from a standstill.

  2. Working memory training improves visual short-term memory capacity.

    PubMed

    Schwarb, Hillary; Nail, Jayde; Schumacher, Eric H

    2016-01-01

    Since antiquity, philosophers, theologians, and scientists have been interested in human memory. However, researchers today are still working to understand the capabilities, boundaries, and architecture. While the storage capabilities of long-term memory are seemingly unlimited (Bahrick, J Exp Psychol 113:1-2, 1984), working memory, or the ability to maintain and manipulate information held in memory, seems to have stringent capacity limits (e.g., Cowan, Behav Brain Sci 24:87-185, 2001). Individual differences, however, do exist and these differences can often predict performance on a wide variety of tasks (cf. Engle What is working-memory capacity? 297-314, 2001). Recently, researchers have promoted the enticing possibility that simple behavioral training can expand the limits of working memory which indeed may also lead to improvements on other cognitive processes as well (cf. Morrison and Chein, Psychol Bull Rev 18:46-60 2011). However, initial investigations across a wide variety of cognitive functions have produced mixed results regarding the transferability of training-related improvements. Across two experiments, the present research focuses on the benefit of working memory training on visual short-term memory capacity-a cognitive process that has received little attention in the training literature. Data reveal training-related improvement of global measures of visual short-term memory as well as of measures of the independent sub-processes that contribute to capacity (Awh et al., Psychol Sci 18(7):622-628, 2007). These results suggest that the ability to inhibit irrelevant information within and between trials is enhanced via n-back training allowing for selective improvement on untrained tasks. Additionally, we highlight a potential limitation of the standard adaptive training procedure and propose a modified design to ensure variability in the training environment.

  3. Short-term outcomes after conventional transthoracic esophagectomy

    PubMed Central

    Niwa, Yukiko; Koike, Masahiko; Hattori, Masashi; Iwata, Naoki; Takami, Hideki; Hayashi, Masamichi; Kanda, Mitsuro; Kobayashi, Daisuke; Tanaka, Chie; Yamada, Suguru; Fujii, Tsutomu; Nakayama, Goro; Sugimoto, Hiroyuki; Nomoto, Shuji; Fujiwara, Michitaka; Kodera, Yasuhiro

    2016-01-01

    ABSTRACT In our department, we have attempted to reduce the incidence of complications of conventional esophagectomy. The objective of this retrospective study was to report the short-term outcomes of esophagectomy. We reviewed 138 consecutive patients who had undergone subtotal esophagectomy by combined laparotomy via a 12-cm upper abdominal vertical incision combined with right anterior muscle-sparing thoracotomy from August 2010 to August 2014. Most of the cervical para-esophageal lymph node dissection was completed within the thoracic cavity. We performed three-field dissection in patients with tumors in the upper or middle third of the esophagus with clinical lymph node metastases in the superior mediastinum; the others underwent two-field dissection. We performed neck anastomoses in patients undergoing three-field dissection and thoracic anastomoses in those undergoing two-field dissection. Effective postoperative pain management was achieved with a combination of epidural anesthesia and paravertebral block. Postoperative rehabilitation was instituted for early ambulation and recovery. Enteral nutrition via a duodenal feeding tube was administered from postoperative day 2. Median hospital stay after surgery was 15 days (range, 10–129). Rates for both 30-day and in-hospital mortality were 0%. Morbidity rate for all Clavien–Dindo grades was 41.3%, whereas the morbidity rate for Clavien–Dindo grades III and IV was 7.2%. Anastomotic leakage developed in two patients (1.4%), recurrent laryngeal nerve palsy in 11 (8.0%), and pneumonia in nine (6.5%). Good short-term outcomes, especially regarding anastomotic leaks, were achieved by consistent improvements in surgical techniques, optimization of several operative procedures, and appropriate perioperative management. PMID:27018983

  4. Memory timeline: Brain ERP C250 (not P300) is an early biomarker of short-term storage.

    PubMed

    Chapman, Robert M; Gardner, Margaret N; Mapstone, Mark; Dupree, Haley M; Antonsdottir, Inga M

    2015-04-16

    Brain event-related potentials (ERPs) offer a quantitative link between neurophysiological activity and cognitive performance. ERPs were measured while young adults performed a task that required storing a relevant stimulus in short-term memory. Using principal components analysis, ERP component C250 (maximum at 250 ms post-stimulus) was extracted from a set of ERPs that were separately averaged for various task conditions, including stimulus relevancy and stimulus sequence within a trial. C250 was more positive in response to task-specific stimuli that were successfully stored in short-term memory. This relationship between C250 and short-term memory storage of a stimulus was confirmed by a memory probe recall test where the behavioral recall of a stimulus was highly correlated with its C250 amplitude. ERP component P300 (and its subcomponents of P3a and P3b, which are commonly thought to represent memory operations) did not show a pattern of activation reflective of storing task-relevant stimuli. C250 precedes the P300, indicating that initial short-term memory storage may occur earlier than previously believed. Additionally, because C250 is so strongly predictive of a stimulus being stored in short-term memory, C250 may provide a strong index of early memory operations.

  5. Memory Timeline: Brain ERP C250 (not P300) is an Early Biomarker of Short-Term Storage

    PubMed Central

    Chapman, Robert M.; Gardner, Margaret N.; Mapstone, Mark; Dupree, Haley M.; Antonsdottir, Inga M.

    2015-01-01

    Brain Event-Related Potentials (ERPs) offer a quantitative link between neurophysiological activity and cognitive performance. ERPs were measured while young adults performed a task that required storing a relevant stimulus in short-term memory. Using Principal Components Analysis, ERP component C250 (maximum at 250 ms post-stimulus) was extracted from a set of ERPs that were separately averaged for various task conditions, including stimulus relevancy and stimulus sequence within a trial. C250 was more positive in response to task-specific stimuli that were successfully stored in short-term memory. This relationship between C250 and short-term memory storage of a stimulus was confirmed by a memory probe recall test where the behavioral recall of a stimulus was highly correlated with its C250 amplitude. ERP component P300 (and its subcomponents of P3a and P3b, which are commonly thought to represent memory operations) did not show a pattern of activation reflective of storing task-relevant stimuli. C250 precedes the P300, indicating that initial short-term memory storage may occur earlier than previously believed. Additionally, because C250 is so strongly predictive of a stimulus being stored in short-term memory, C250 may provide a strong index of early memory operations. PMID:25641043

  6. Short term memory of Caenorhabditis elegans against bacterial pathogens involves CREB transcription factor.

    PubMed

    Prithika, Udayakumar; Vikneswari, Ramaraj; Balamurugan, Krishnaswamy

    2017-04-01

    One of the key issues pertaining to the control of memory is to respond to a consistently changing environment or microbial niche present in it. Human cyclic AMP response element binding protein (CREB) transcription factor which plays a crucial role in memory has a homolog in C. elegans, crh-1. crh-1 appears to influence memory processes to certain extent by habituation of the host to a particular environment. The discrimination between the pathogen and a non-pathogen is essential for C. elegans in a microbial niche which determines its survival. Training the nematodes in the presence of a virulent pathogen (S. aureus) and an opportunistic pathogen (P. mirabilis) separately exhibits a different behavioural paradigm. This appears to be dependent on the CREB transcription factor. Here we show that C. elegans homolog crh-1 helps in memory response for a short term against the interacting pathogens. Following conditioning of the nematodes to S. aureus and P. mirabilis, the wild type nematodes exhibited a positive response towards the respective pathogens which diminished slowly after 2h. By contrast, the crh-1 deficient nematodes had a defective memory post conditioning. The molecular data reinforces the importance of crh-1 gene in retaining the memory of nematode. Our results also suggest that involvement of neurotransmitters play a crucial role in modulating the memory of the nematode with the assistance of CREB. Therefore, we elucidate that CREB is responsible for the short term memory response in C. elegans against bacterial pathogens.

  7. Short-Term International Internship Experiences for Future Teachers and Other Child Development Professionals

    ERIC Educational Resources Information Center

    Miller, Kari Knutson; Gonzalez, Amber M.

    2016-01-01

    This paper examines outcomes associated with participation in short-term, international internship experiences. Results suggest short-term international internship experiences contribute to rich personal and professional development outcomes. Findings highlight participant challenges associated with initial internship experiences, professional…

  8. Short-term effects of hydrogen fluoride on Nicotiana tabacum L.

    PubMed

    Döğeroğlu, Tuncay; Ciçek, Arzu; Kara, Serap

    2003-09-01

    Data on the short-term effects of fumigation with hydrogen fluoride (HF) on the response behavior of the Nicotiana tabacum L. cv. St. Karabalar 6265 are being presented. Growth rate, fluoride accumulation in leaves and soils, and degradation in chlorophyll and nicotine contents of the plant species against the variations in two experimental factors, namely the exposure concentration and exposure time parameters, were investigated. Resulting data reveals that the variety selected for this study is not so tolerant to fluoride as generally reported in the literature, if only the individual effects of the pollutant is considered.

  9. The influence of infrared radiation on short-term ultraviolet-radiation-induced injuries

    SciTech Connect

    Kaidbey, K.H.; Witkowski, T.A.; Kligman, A.M.

    1982-05-01

    Because heat has been reported to influence adversely short- and long-term ultraviolet (UV)-radiation-induced skin damage in animals, we investigated the short-term effects of infrared radiation on sunburn and on phototoxic reactions to topical methoxsalen and anthracene in human volunteers. Prior heating of the skin caused suppression of the phototoxic response to methoxsalen as evidenced by an increase in the threshold erythema dose. Heat administered either before or after exposure to UV radiation had no detectable influence on sunburn erythema or on phototoxic reactions provoked by anthracene.

  10. Short-term oscillations in avian molt intensity: Evidence from the golden eagle Aquila chrysaetos

    USGS Publications Warehouse

    Ellis, D.H.; Lish, J.W.; Kery, M.; Redpath, S.M.

    2006-01-01

    From a year-long study of molt in the golden eagle Aquila chrysaetos, we recorded 2069 contour feathers replaced in 137 d (6 May-19 September). Very few contour feathers were lost outside this period. From precise daily counts of feathers lost, and using time series analysis, we identified short-term fluctuations (i.e., 19-d subcycles) around a midsummer peak (i.e., a left-skewed normal distribution). Because these subcycles have never before been reported and because the physiological basis for many aspects of avian molt is poorly known, we offer only hypothetical explanations for the controls responsible for the subcycles. ?? Journal of Avian Biology.

  11. Short-term oscillations in avian molt intensity: evidence from the golden eagle Aquila chrysaetos

    USGS Publications Warehouse

    Ellis, D.H.; Lish, J.W.; Kery, M.; Redpath, S.M.

    2006-01-01

    From a year-long study of molt in the golden eagle Aquila chrysaetos, we recorded 2069 contour feathers replaced in 137 d (6 May-19 September). Very few contour feathers were lost outside this period. From precise daily counts of feathers lost, and using time series analysis, we identified short-term fluctuations (i.e., 19-d subcycles) around a midsummer peak (i.e., a left-skewed normal distribution). Because these subcycles have never before been reported and because the physiological basis for many aspects of avian molt is poorly known, we offer only hypothetical explanations for the controls responsible for the subcycles.

  12. Short term change in relative humidity during the festival of Diwali in India

    NASA Astrophysics Data System (ADS)

    Ganguly, Nandita D.

    2015-07-01

    The changes in humidity levels during the Diwali festivities have been examined over a period of 13 years at three Indian metro cities: Ahmedabad, New Delhi and Kolkata. A small short term increase in relative humidity even in the absence of transport of humid air from Arabian Sea and Bay of Bengal has been observed. The relative humidity levels were found to be exceeding the ambient levels during night and lying below the ambient levels during morning hours, indicating an increase in the survival rates of viruses responsible for the transmission of viral infections, as well as triggering immune-mediated illnesses such as asthma during Diwali.

  13. Dramatic volume reduction of a large GH/TSH secreting pituitary tumor with short term Octreotide therapy.

    PubMed

    Atkinson, John L D; Abboud, Charles F; Lane, John I

    2005-01-01

    A case is presented of a huge GH/TSH secreting tumor and marked volumetric reduction in size with only one week of Octreotide therapy. To our knowledge, this is the first reported case of such a dramatic volumetric response to short-term Octreotide therapy.

  14. Development of Short-term Molecular Thresholds to Predict Long-term Mouse Liver Tumor Outcomes: Phthalate Case Study

    EPA Science Inventory

    Short-term molecular profiles are a central component of strategies to model health effects of environmental chemicals. In this study, a 7 day mouse assay was used to evaluate transcriptomic and proliferative responses in the liver for a hepatocarcinogenic phthalate, di (2-ethylh...

  15. Fuzzy system applications for short-term electric load forecasting

    NASA Astrophysics Data System (ADS)

    Al-Kandari, Ahmad Mohammad

    Load forecasting is an important function in economic power generation, allocation between plants (Unit Commitment Scheduling), maintenance scheduling, and for system security applications such as peak shaving by power interchange with interconnected utilities. In this thesis the problem of fuzzy short term load forecasting is formulated and solved. The thesis starts with a discussion of conventional algorithms used in short-term load forecasting. These algorithms are based on least error squares and least absolute value. The theory behind each algorithm is explained. Three different models are developed and tested in the first part of the thesis. The first model (A) is a regression model that takes into account the weather parameters in summer and winter seasons. The second model (B) is a harmonics based model, which does not account for weather parameters, but considers the parameters as a function of time. Model (B) can be used where variations in weather parameters are not available. Finally, model (C) is created as a hybrid combination of models A and B. The parameters of the three models are estimated using the two static estimation algorithms and are used later to predict the load for twenty-four hours ahead. The results obtained are discussed and conclusions are drawn for these models. In the second part of the thesis new fuzzy models are developed for crisp load power with fuzzy load parameters and for fuzzy load power with fuzzy load parameters. Three fuzzy models (A), (B) and (C) are developed. The fuzzy load model (A) is a fuzzy linear regression model for summer and winter seasons. Model (B) is a harmonic fuzzy model, which does not account for weather parameters. Finally fuzzy load model (C) is a hybrid combination of fuzzy load models (A) and (B). Estimating the fuzzy parameters for the three models turns out to be one of linear optimization. The fuzzy parameters are obtained for the three models. These parameters are used to predict the load as a

  16. 22 CFR 71.11 - Short-term full diet program.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Short-term full diet program. 71.11 Section 71.... Nationals Incarcerated Abroad § 71.11 Short-term full diet program. (a) Eligibility criteria. A prisoner is considered eligible for the short-term full diet program under the following general criteria: (1)...

  17. 22 CFR 71.11 - Short-term full diet program.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Short-term full diet program. 71.11 Section 71.... Nationals Incarcerated Abroad § 71.11 Short-term full diet program. (a) Eligibility criteria. A prisoner is considered eligible for the short-term full diet program under the following general criteria: (1)...

  18. 22 CFR 71.11 - Short-term full diet program.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Short-term full diet program. 71.11 Section 71.... Nationals Incarcerated Abroad § 71.11 Short-term full diet program. (a) Eligibility criteria. A prisoner is considered eligible for the short-term full diet program under the following general criteria: (1)...

  19. 22 CFR 71.11 - Short-term full diet program.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Short-term full diet program. 71.11 Section 71.... Nationals Incarcerated Abroad § 71.11 Short-term full diet program. (a) Eligibility criteria. A prisoner is considered eligible for the short-term full diet program under the following general criteria: (1)...

  20. 22 CFR 71.11 - Short-term full diet program.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Short-term full diet program. 71.11 Section 71.... Nationals Incarcerated Abroad § 71.11 Short-term full diet program. (a) Eligibility criteria. A prisoner is considered eligible for the short-term full diet program under the following general criteria: (1)...

  1. 24 CFR 576.106 - Short-term and medium-term rental assistance.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 3 2012-04-01 2012-04-01 false Short-term and medium-term rental... and Eligible Activities § 576.106 Short-term and medium-term rental assistance. (a) General provisions... assistance may be short-term rental assistance, medium-term rental assistance, payment of rental arrears,...

  2. 24 CFR 576.106 - Short-term and medium-term rental assistance.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 3 2013-04-01 2013-04-01 false Short-term and medium-term rental... and Eligible Activities § 576.106 Short-term and medium-term rental assistance. (a) General provisions... assistance may be short-term rental assistance, medium-term rental assistance, payment of rental arrears,...

  3. 24 CFR 576.106 - Short-term and medium-term rental assistance.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 3 2014-04-01 2013-04-01 true Short-term and medium-term rental... and Eligible Activities § 576.106 Short-term and medium-term rental assistance. (a) General provisions... assistance may be short-term rental assistance, medium-term rental assistance, payment of rental arrears,...

  4. Short-Term Effects of Midseason Coach Turnover on Team Performance in Soccer

    ERIC Educational Resources Information Center

    Balduck, Anne-Line; Buelens, Marc; Philippaerts, Renaat

    2010-01-01

    The present study addressed the issue of short-term performance effects of midseason coach turnover in soccer. The goal of this study was to examine this effect on subsequent short-term team performance. The purposes of this study were to (a) examine whether midseason coach turnover improved results in the short term, and (b) examine how team…

  5. Short-Term Memory Trace in Rapidly Adapting Synapses of Inferior Temporal Cortex

    PubMed Central

    Sugase-Miyamoto, Yasuko; Liu, Zheng; Wiener, Matthew C.; Optican, Lance M.; Richmond, Barry J.

    2008-01-01

    Visual short-term memory tasks depend upon both the inferior temporal cortex (ITC) and the prefrontal cortex (PFC). Activity in some neurons persists after the first (sample) stimulus is shown. This delay-period activity has been proposed as an important mechanism for working memory. In ITC neurons, intervening (nonmatching) stimuli wipe out the delay-period activity; hence, the role of ITC in memory must depend upon a different mechanism. Here, we look for a possible mechanism by contrasting memory effects in two architectonically different parts of ITC: area TE and the perirhinal cortex. We found that a large proportion (80%) of stimulus-selective neurons in area TE of macaque ITCs exhibit a memory effect during the stimulus interval. During a sequential delayed matching-to-sample task (DMS), the noise in the neuronal response to the test image was correlated with the noise in the neuronal response to the sample image. Neurons in perirhinal cortex did not show this correlation. These results led us to hypothesize that area TE contributes to short-term memory by acting as a matched filter. When the sample image appears, each TE neuron captures a static copy of its inputs by rapidly adjusting its synaptic weights to match the strength of their individual inputs. Input signals from subsequent images are multiplied by those synaptic weights, thereby computing a measure of the correlation between the past and present inputs. The total activity in area TE is sufficient to quantify the similarity between the two images. This matched filter theory provides an explanation of what is remembered, where the trace is stored, and how comparison is done across time, all without requiring delay period activity. Simulations of a matched filter model match the experimental results, suggesting that area TE neurons store a synaptic memory trace during short-term visual memory. PMID:18464917

  6. Application of Remote Sensing to Assess the Impact of Short Term Climate Variability on Coastal Sedimentation

    NASA Technical Reports Server (NTRS)

    Menzel, W. Paul; Huh, Oscar K.; Walker, Nan

    2004-01-01

    The purpose of this joint University of Wisconsin (UW) and Louisiana State University (LSU) project has been to relate short term climate variation to response in the coastal zone of Louisiana in an attempt to better understand how the coastal zone is shaped by climate variation. Climate variation in this case largely refers to variation in surface wind conditions that affect wave action and water currents in the coastal zone. The primary region of focus was the Atchafalaya Bay and surrounding bays in the central coastal region of Louisiana. Suspended solids in the water column show response to wind systems both in quantity (through resuspension) and in the pattern of dispersement or transport. Wind systems associated with cold fronts are influenced by short term climate variation. Wind energy was used as the primary signature of climate variation in this study because winds are a significant influence on sediment transport in the micro-tidal Gilf of Mexico coastal zone. Using case studies, the project has been able to investigate the influence of short term climate variation on sediment transport. Wind energy data, collected daily for National Weather Service (NWS) stations at Lake Charles and New Orleans, LA, were used as an indicator of short term climate variation influence on seasonal time scales. A goal was to relate wind energy to coastal impact through sediment transport. This goal was partially accomplished by combining remote sensing and wind energy data. Daily high resolution remote sensing observations are needed to monitor the complex coastal zone environment, where winds, tides, and water level all interact to influence sediment transport. The NASA Earth Observing System (EOS) era brings hope for documenting and revealing response of the complex coastal transport mosaic through regular high spatial resolution observations from the Moderate resolution Imaging Spectrometer (MODIS) instrument. MODIS observations were sampled in this project for

  7. Assessing the short-term effects of an extreme storm on Mediterranean forest raptors

    NASA Astrophysics Data System (ADS)

    Martínez, José E.; Jiménez-Franco, María V.; Zuberogoitia, Iñigo; León-Ortega, Mario; Calvo, José F.

    2013-04-01

    Different species show different responses to natural disturbances, depending on their capacity to exploit the altered environment and occupy new niches. In the case of semi-arid Mediterranean areas, there is no information available on the response of bird communities to disturbance caused by extreme weather events. Here, we evaluate the short-term effects of a heavy snowfall and strong winds on three long-lived species of forest-dwelling raptor in a semi-arid Mediterranean region situated in the south-east of Spain. The loss of nests was significantly higher in the first and second years following the disturbance than in the third year. The three species studied exhibited great tolerance to the short-term effects of the storm since we found no differences in density or reproductive parameters between the nine breeding seasons prior to the disturbance and the three which immediately followed it. We suggest that the tolerance shown by these three species to windstorms in semi-arid Mediterranean zones could be an adaptive response, resulting from the climatic and human pressures which have prevailed from the Bronze Age to the present day.

  8. A Single Brief Burst Induces GluR1-Dependent Associative Short-Term Potentiation: A Potential Mechanism for Short-Term Memory

    ERIC Educational Resources Information Center

    Erickson, Martha A.; Maramara, Lauren A.; Lisman, John

    2010-01-01

    Recent work showed that short-term memory (STM) is selectively reduced in GluR1 knockout mice. This raises the possibility that a form of synaptic modification dependent on GluR1 might underlie STM. Studies of synaptic plasticity have shown that stimuli too weak to induce long-term potentiation induce short-term potentiation (STP), a phenomenon…

  9. Short-Term Musical Training and Pyschoacoustical Abilities

    PubMed Central

    Jain, Chandni; Mohamed, Hijas; Kumar, Ajith U.

    2014-01-01

    The aim of the study was to assess the effect of short-term perceptual training of music on some psycho-acoustical measures. The study was carried out in three phases. In first the phase pre-training evaluation was done which included raga identification and various psycho acoustical tests. Psycho-acoustical tests included measurement of differential limen of frequency and intensity, duration discrimination, gap detection, modulation detection, backward masking and duration pattern test. In the second phase, auditory perceptual training was given for raga identification and in the third phase post- training evaluation was done though same tests as mentioned in pre-training phase. A total of 10 normal hearing adults (7 males, 3 females) in the age range of 18-25 years participated in the study. The results revealed that all the subjects performed significantly better on raga identification after training. However; there was no significant difference in psycho-acoustical measures in pre and post-training. PMID:26557354

  10. Local short-term variability in solar irradiance

    NASA Astrophysics Data System (ADS)

    Lohmann, Gerald M.; Monahan, Adam H.; Heinemann, Detlev

    2016-05-01

    Characterizing spatiotemporal irradiance variability is important for the successful grid integration of increasing numbers of photovoltaic (PV) power systems. Using 1 Hz data recorded by as many as 99 pyranometers during the HD(CP)2 Observational Prototype Experiment (HOPE), we analyze field variability of clear-sky index k* (i.e., irradiance normalized to clear-sky conditions) and sub-minute k* increments (i.e., changes over specified intervals of time) for distances between tens of meters and about 10 km. By means of a simple classification scheme based on k* statistics, we identify overcast, clear, and mixed sky conditions, and demonstrate that the last of these is the most potentially problematic in terms of short-term PV power fluctuations. Under mixed conditions, the probability of relatively strong k* increments of ±0.5 is approximately twice as high compared to increment statistics computed without conditioning by sky type. Additionally, spatial autocorrelation structures of k* increment fields differ considerably between sky types. While the profiles for overcast and clear skies mostly resemble the predictions of a simple model published by , this is not the case for mixed conditions. As a proxy for the smoothing effects of distributed PV, we finally show that spatial averaging mitigates variability in k* less effectively than variability in k* increments, for a spatial sensor density of 2 km-2.

  11. Optimize Short Term load Forcasting Anomalous Based Feed Forward Backpropagation

    NASA Astrophysics Data System (ADS)

    Mulyadi, Y.; Abdullah, A. G.; Rohmah, K. A.

    2017-03-01

    This paper contains the Short-Term Load Forecasting (STLF) using artificial neural network especially feed forward back propagation algorithm which is particularly optimized in order to getting a reduced error value result. Electrical load forecasting target is a holiday that hasn’t identical pattern and different from weekday’s pattern, in other words the pattern of holiday load is an anomalous. Under these conditions, the level of forecasting accuracy will be decrease. Hence we need a method that capable to reducing error value in anomalous load forecasting. Learning process of algorithm is supervised or controlled, then some parameters are arranged before performing computation process. Momentum constant a value is set at 0.8 which serve as a reference because it has the greatest converge tendency. Learning rate selection is made up to 2 decimal digits. In addition, hidden layer and input component are tested in several variation of number also. The test result leads to the conclusion that the number of hidden layer impact on the forecasting accuracy and test duration determined by the number of iterations when performing input data until it reaches the maximum of a parameter value.

  12. Short term fluctuations of wind and solar power systems

    NASA Astrophysics Data System (ADS)

    Anvari, M.; Lohmann, G.; Wächter, M.; Milan, P.; Lorenz, E.; Heinemann, D.; Rahimi Tabar, M. Reza; Peinke, Joachim

    2016-06-01

    Wind and solar power are known to be highly influenced by weather events and may ramp up or down abruptly. Such events in the power production influence not only the availability of energy, but also the stability of the entire power grid. By analysing significant amounts of data from several regions around the world with resolutions of seconds to minutes, we provide strong evidence that renewable wind and solar sources exhibit multiple types of variability and nonlinearity in the time scale of seconds and characterise their stochastic properties. In contrast to previous findings, we show that only the jumpy characteristic of renewable sources decreases when increasing the spatial size over which the renewable energies are harvested. Otherwise, the strong non-Gaussian, intermittent behaviour in the cumulative power of the total field survives even for a country-wide distribution of the systems. The strong fluctuating behaviour of renewable wind and solar sources can be well characterised by Kolmogorov-like power spectra and q-exponential probability density functions. Using the estimated potential shape of power time series, we quantify the jumpy or diffusive dynamic of the power. Finally we propose a time delayed feedback technique as a control algorithm to suppress the observed short term non-Gaussian statistics in spatially strong correlated and intermittent renewable sources.

  13. Short-term stabilization of grape marc through earthworms.

    PubMed

    Gómez-Brandón, María; Lazcano, Cristina; Lores, Marta; Domínguez, Jorge

    2011-03-15

    The winery industry generates vast amounts of organic waste during the various stages of wine production. Among the possible methodological alternatives available for its treatment, vermicomposting is one of the best-known processes for the biological stabilization of solid organic wastes by transforming them into safer and more stabilized materials suitable for application to soil. In this study we carried out a mesocosm experiment to evaluate the effectiveness of the active phase of vermicomposting for the stabilization of grape marc, an enriched lignocellulosic by-product obtained after the grape crushing and pressing stages in wine production. For this we analysed the chemical, biochemical and microbiological properties of the product resulting from this phase, in comparison with those in a control treatment. Earthworm activity reduced the abundance of both bacterial and fungal PLFA biomarkers. Decreases in microbial activity and in protease and cellulase activities were also attributed to the presence of earthworms. The differences in microbial communities were accompanied by a reduction in the labile C pool and the cellulose content. These results indicate that earthworms played a key role in the stabilization of the grape marc in the short-term, via its effects on organic matter decomposition and microbial biomass and activity.

  14. Field comparison of commercially available short-term radon detectors.

    PubMed

    Sun, Kainan; Majdan, Marek; Field, Daniel W; Field, R William

    2006-09-01

    We performed a comparison of commercially available short-term radon detectors in order to determine the accuracy and precision of the detectors under actual field conditions. We exposed fifteen radon detectors, under field conditions, from each of six companies to a reference radon concentration. Five of the six companies tested did not pass the U.S. Environmental Protection Agency's previously established accuracy guideline (all individual relative errors

  15. Tactile short-term memory in sensory-deprived individuals.

    PubMed

    Papagno, Costanza; Minniti, Giovanna; Mattavelli, Giulia C; Mantovan, Lara; Cecchetto, Carlo

    2017-02-01

    To verify whether loosing a sense or two has consequences on a spared sensory modality, namely touch, and whether these consequences depend on practice or are biologically determined, we investigated 13 deafblind participants, 16 deaf participants, 15 blind participants, and 13 matched normally sighted and hearing controls on a tactile short-term memory task, using checkerboard matrices of increasing length in which half of the squares were made up of a rough texture and half of a smooth one. Time of execution of a fixed matrix, number of correctly reproduced matrices, largest matrix correctly reproduced and tactile span were recorded. The three groups of sensory-deprived individuals did not differ in any measure, while blind and deaf participants outscored controls in all parameters except time of execution; the difference approached significance for deafblind people compared to controls only in one measure, namely correctly reproduced matrices. In blind and deafblind participants, performance negatively correlated with age of Braille acquisition, the older being the subject when acquiring Braille, the lower the performance, suggesting that practice plays a role. However, the fact that deaf participants, who did not share tactile experience, performed similarly to blind participants and significantly better than controls highlights that practice cannot be the only contribution to better tactile memory.

  16. Short-term energy outlook, quarterly projections, first quarter 1998

    SciTech Connect

    1998-01-01

    The forecast period for this issue of the Outlook extends from the first quarter of 1998 through the fourth quarter of 1999. Values for the fourth quarter of 1997, however, are preliminary EIA estimates (for example, some monthly values for petroleum supply and disposition are derived in part from weekly data reported in EIA`s Weekly Petroleum Status Report) or are calculated from model simulations that use the latest exogenous information available (for example, electricity sales and generation are simulated by using actual weather data). The historical energy data, compiled in the first quarter 1998 version of the Short-Term Integrated Forecasting System (STIFS) database, are mostly EIA data regularly published in the Monthly Energy Review, Petroleum Supply Monthly, and other EIA publications. Minor discrepancies between the data in these publications and the historical data in this Outlook are due to independent rounding. The STIFS model is driven principally by three sets of assumptions or inputs: estimates of key macroeconomic variables, world oil price assumptions, and assumptions about the severity of weather. Macroeconomic estimates are adjusted by EIA to reflect EIA assumptions which may affect the macroeconomic outlook. By varying the assumptions, alternative cases are produced by using the STIFS model. 24 figs., 19 tabs.

  17. Short term effects of airborne pollen concentrations on asthma epidemic

    PubMed Central

    Tobias, A; Galan, I; Banegas, J; Aranguez, E

    2003-01-01

    Methods: This study, based on time series analysis adjusting for meteorological factors and air pollution variables, assessed the short term effects of different types of allergenic pollen on asthma hospital emergencies in the metropolitan area of Madrid (Spain) for the period 1995–8. Results: Statistically significant associations were found for Poaceae pollen (lag of 3 days) and Plantago pollen (lag of 2 days), representing an increase in the range between the 99th and 95th percentiles of 17.1% (95% confidence interval (CI) 3.2 to 32.8) and 15.9% (95% CI 6.5 to 26.2) for Poaceae and Plantago, respectively. A positive association was also observed for Urticaceae (lag of 1 day) with an 8.4% increase (95% CI 2.8 to 14.4). Conclusions: There is an association between pollen levels and asthma related emergencies, independent of the effect of air pollutants. The marked relationship observed for Poaceae and Plantago pollens suggests their implication in the epidemic distribution of asthma during the period coinciding with their abrupt release into the environment. PMID:12885991

  18. Genotoxicity Assessment of Erythritol by Using Short-term Assay

    PubMed Central

    Chung, Young-Shin

    2013-01-01

    Erythritol is a sugar alcohol that is widely used as a natural sugar substitute. Thus, the safety of its usage is very important. In the present study, short-term genotoxicity assays were conducted to evaluate the potential genotoxic effects of erythritol. According to the OECD test guidelines, the maximum test dose was 5,000 μg/plate in bacterial reverse mutation tests, 5,000 μg/ml in cell-based assays, and 5,000 mg/kg for in vivo testing. An Ames test did not reveal any positive results. No clastogenicity was observed in a chromosomal aberration test with CHL cells or an in vitro micronucleus test with L5178Y tk+/− cells. Erythritol induced a marginal increase of DNA damage at two high doses by 24 hr of exposure in a comet assay using L5178Y tk+/− cells. Additionally, in vivo micronucleus tests clearly demonstrated that oral administration of erythritol did not induce micronuclei formation of the bone marrow cells of male ICR mice. Taken together, our results indicate that erythritol is not mutagenic to bacterial cells and does not cause chromosomal damage in mammalian cells either in vitro or in vivo. PMID:24578795

  19. Short-Term Dynamical Interactions Among Extrasolar Planets

    NASA Technical Reports Server (NTRS)

    Laughlin, Gregory; Chambers, John E.; DiVincenzi, Donald (Technical Monitor)

    2001-01-01

    We show that short-term perturbations among massive planets in multiple planet systems can result in radial velocity variations of the central star which differ substantially from velocity variations derived assuming the planets are executing independent Keplerian motions. We discuss two alternate fitting methods which can lead to an improved dynamical description of multiple planet systems. In the first method, the osculating orbital elements are determined via a Levenberg-Marquardt minimization scheme driving an N-body integrator. The second method is an improved analytic model in which orbital elements such as the periods and longitudes of periastron are allowed to vary according to a simple model for resonant interactions between the planets. Both of these methods can potentially determine the true masses for the planets by eliminating the sin(i) degeneracy inherent in fits that assume independent Keplerian motions. As more radial velocity data is accumulated from stars such as GJ876, these methods should allow for unambiguous determination of the planetary masses and relative inclinations.

  20. Short-term memory stores organized by information domain.

    PubMed

    Noyce, Abigail L; Cestero, Nishmar; Shinn-Cunningham, Barbara G; Somers, David C

    2016-04-01

    Vision and audition have complementary affinities, with vision excelling in spatial resolution and audition excelling in temporal resolution. Here, we investigated the relationships among the visual and auditory modalities and spatial and temporal short-term memory (STM) using change detection tasks. We created short sequences of visual or auditory items, such that each item within a sequence arose at a unique spatial location at a unique time. On each trial, two successive sequences were presented; subjects attended to either space (the sequence of locations) or time (the sequence of inter item intervals) and reported whether the patterns of locations or intervals were identical. Each subject completed blocks of unimodal trials (both sequences presented in the same modality) and crossmodal trials (Sequence 1 visual, Sequence 2 auditory, or vice versa) for both spatial and temporal tasks. We found a strong interaction between modality and task: Spatial performance was best on unimodal visual trials, whereas temporal performance was best on unimodal auditory trials. The order of modalities on crossmodal trials also mattered, suggesting that perceptual fidelity at encoding is critical to STM. Critically, no cost was attributable to crossmodal comparison: In both tasks, performance on crossmodal trials was as good as or better than on the weaker unimodal trials. STM representations of space and time can guide change detection in either the visual or the auditory modality, suggesting that the temporal or spatial organization of STM may supersede sensory-specific organization.

  1. Reducing variability in short term orbital lifetime prediction

    NASA Astrophysics Data System (ADS)

    Kebschull, Christopher; Flegel, Sven Kevin; Braun, Vitali; Gelhaus, Johannes; Möckel, Marek; Wiedemann, Carsten; Vörsmann, Peter

    2013-04-01

    Within the last year three major re-entries occurred. The satellites UARS, ROSAT and Phobos-Grunt entered Earth's atmosphere with fragments reaching the surface. Due to a number of uncertainties in propagating an object's trajectory the exact place and time of a satellite's re-entry is hard to determine. Major influences when predicting the re-entry time are the changing precision of the available orbital data, the satellite's ballistic coefficient, the activity of the sun which influences the Earth's atmosphere and the underlying quality of the atmospheric model. In this paper a method is presented which can reduce the variability in short-term orbital lifetime prediction induced by fluctuating orbital data accuracies. A re-entry campaign is used as a reference for this purpose. For a window of a few weeks before the re-entry the position data of a synthetic object is disturbed considering different degrees of orbital data errors. As a result different predictions will exist for the generated position data of a given day. Using a regression algorithm on the available data an average position is obtained, which is then used for the orbital lifetime prediction. The effect of this measure is a more consistent prediction of the orbital lifetime. The paper concludes with the comparison of the generated re-entry windows in various test cases for the original and the averaged data.

  2. Role of short-term memory in loudness comparisons

    NASA Astrophysics Data System (ADS)

    Ellermeier, Wolfgang; Werner, Birgit

    2003-04-01

    In an earlier study of the auditory discrimination of time-varying noise bursts [Ellermeier and Schrödl, J. Acoust. Soc. Am. 108, 2596 (2000)], listeners were found to place greater weight on the beginning and end of the sounds than on the middle portion. To investigate whether this outcome is due to primacy and recency effects in short-term memory which tend to be sensitive to manipulations of the inter-stimulus interval (ISI), the ISI separating the two noise bursts in a 2IFC task was varied systematically. Six participants performed loudness comparisons on 1-s samples of white noise randomly changing in level every 100 ms. In different blocks of trials, the two noise bursts to be compared were either separated by a 500-ms or a 2-s ISI. COSS analysis [Berg, J. Acoust. Soc. Am. 86, 1743-1746 (1989)] of the overall loudness judgments revealed elevated weights for the beginning and end of the noises, as in the earlier study. These weighting patterns were largely unaffected by the manipulation of ISI, suggesting that the temporal weights found characterize loudness integration in general, and are not just due to idiosyncrasies of the timing used in the 2IFC procedure.

  3. Thermodynamics of short-term cell adhesion in vitro.

    PubMed Central

    Vogler, E A

    1988-01-01

    A thermodynamic theory of short-term (less than 2 hr) in vitro cell adhesion has been developed which allows calculation of reversible work of adhesion and estimation of a term proportional to cell-substrate contact area. The theory provides a means of determining a parameter related to membrane wetting tension for microscopic cells that does not require special manipulations which might desiccate or denature delicate cell membranes. Semiquantitative agreement between predicted and experimentally-measured cell adhesion obtained for three different cell types (MDCK, RBL-1, and HCT-15) in two different liquid phase compositions of surfactants (Tween-80 and fetal bovine serum) supports concepts and approximations utilized in development of theory. Cell-substrate contact areas were largest for wettable surfaces treated with ionizing corona or plasma discharges and smallest for hydrophobic materials for each cell type studied. Contact area for the continuous dog-kidney cell line MDCK was larger than that of either the leukemic blood cell RBL-1 or the anaplastic human colon cell HCT-15. PMID:3390519

  4. Probing short-term face memory in developmental prosopagnosia.

    PubMed

    Shah, Punit; Gaule, Anne; Gaigg, Sebastian B; Bird, Geoffrey; Cook, Richard

    2015-03-01

    It has recently been proposed that the face recognition deficits seen in neurodevelopmental disorders may reflect impaired short-term face memory (STFM). For example, introducing a brief delay between the presentation of target and test faces seems to disproportionately impair matching or recognition performance in individuals with Autism Spectrum Disorders. The present study sought to determine whether deficits of STFM contribute to impaired face recognition seen in Developmental Prosopagnosia. To determine whether developmental prosopagnosics exhibit impaired STFM, the present study used a six-alternative-forced-choice match-to-sample procedure. Memory demand was manipulated by employing a short or long delay between the presentation of the target face, and the six test faces. Crucially, the perceptual demands were identical in both conditions, thereby allowing the independent contribution of STFM to be assessed. Prosopagnosics showed clear evidence of a category-specific impairment for face-matching in both conditions; they were both slower and less accurate than matched controls. Crucially, however, the prosopagnosics showed no evidence of disproportionate face recognition impairment in the long-interval condition. While individuals with DP may have problems with the perceptual encoding of faces, it appears that their representations are stable over short durations. These results suggest that the face recognition difficulties seen in DP and autism may be qualitatively different, attributable to deficits of perceptual encoding and perceptual maintenance, respectively.

  5. Short-Term Outcomes and Mortality of Late Preterm Infants

    PubMed Central

    Bulut, Cahide; Gürsoy, Tuğba; Ovalı, Fahri

    2016-01-01

    Background: Late preterm infants have increased rates of morbidity and mortality compared to term infants. Determining the risk factors in these infants leads to more comprehensive preventive and treatment strategies. Aims: Our aim was to analyse the morbidity rates such as respiratory system diseases, infections, congenital anomalies, hypoglycemia and hematologic abnormalities and mortality rates in a large group of patients at a referral center. Study Design: Retrospective cross-sectional study. Methods: Medical records of late preterm and term infants who were managed at the referral center were analysed. Results: 41752 births were analysed in 3 years. 71.9% of all births were between 37–42 gestational weeks (i.e. term) and 16.1% were between 34–37 weeks (i.e. late preterm). Compared to term infants, late preterm infants had increased rates of short-term problems. The rate of mortality increased with decreased gestational age. The duration of hospitalization was significantly higher in the smallest late preterm infants. Conclusion: This study demonstrated the need that late preterm infants who have higher risk for morbidity and mortality, compared to term infants require close monitoring. The rate of mortality and hospitalization increased with decreased gestational age. PMID:27403390

  6. Distinct responses of planktonic foraminiferal B/Ca to dissolution on seafloor

    NASA Astrophysics Data System (ADS)

    Dai, Yuhao; Yu, Jimin; Johnstone, Heather J. H.

    2016-04-01

    We have measured B/Ca in four core-top planktonic foraminiferal species (Globigerinoides ruber (white), Globigerinoides sacculifer (without final sac-like chamber), Neogloboquadrina dutertrei, and Pulleniatina obliquiloculata) from three depth transects (the Caribbean Sea, the southwestern Indian Ocean, and the Ontong Java Plateau) to evaluate the effect of dissolution on planktonic foraminiferal B/Ca. At each transect, G. ruber (w) and G. sacculifer (w/o sac) show decreasing B/Ca with increasing water depth. This decrease in B/Ca is accompanied with decreases in shell weights, Mg/Ca, and bottom water calcite saturation state. This indicates a postdepositional dissolution effect on B/Ca in these two species. The strong correlation observed between changes in B/Ca and bottom water calcite saturation state offers an approach to correcting for the dissolution bias. By contrast, B/Ca in N. dutertrei and P. obliquiloculata remains unchanged along depth transects, although shell weights and Mg/Ca display significant declines. Overall, our core-top results suggest species-specific dissolution effects on B/Ca in different planktonic foraminiferal species.

  7. New trends of short-term humanitarian medical volunteerism: professional and ethical considerations.

    PubMed

    Asgary, Ramin; Junck, Emily

    2013-10-01

    Short-term humanitarian medical volunteerism has grown significantly among both clinicians and trainees over the past several years. Increasingly, both volunteers and their respective institutions have faced important challenges in regard to medical ethics and professional codes that should not be overlooked. We explore these potential concerns and their risk factors in three categories: ethical responsibilities in patient care, professional responsibility to communities and populations, and institutional responsibilities towards trainees. We discuss factors increasing the risk of harm to patients and communities, including inadequate preparation, the use of advanced technology and the translation of Western medicine, issues with clinical epidemiology and test utility, difficulties with the principles of justice and clinical justice, the lack of population-based medicine, sociopolitical effects of foreign aid, volunteer stress management, and need for sufficient trainee supervision. We review existing resources and offer suggestions for future skill-based training, organisational responsibilities, and ethical preparation.

  8. High-dose short-term administration of naringin did not alter talinolol pharmacokinetics in humans.

    PubMed

    Nguyen, M A; Staubach, P; Tamai, I; Langguth, P

    2015-02-20

    Naringin is considered the major causative ingredient of the inhibition of intestinal drug uptake by grapefruit juice. Moreover, it is contained in highly dosed nutraceuticals available on the market. A controlled, open, randomized, crossover study was performed in 10 healthy volunteers to investigate the effect of high-dose naringin on the bioavailability of talinolol, a substrate of intestinal organic anion-transporting polypeptide (OATP)-mediated uptake. Following 6-day supplementation with 3 capsules of 350 mg naringin daily, 100mg talinolol were administered orally with 3 capsules of the same dietary supplement (1050 mg naringin) on the seventh day. This test treatment was compared to 100mg talinolol only (control). The results showed that short-term high-dose naringin supplementation did not significantly affect talinolol pharmacokinetics. Geometric mean ratios of test versus control ranged between 0.90 and 0.98 for talinolol c(max), AUC(0-48 h), AUC(0-∞), t(1/2) and A(e(0-48 h)). The high dose may provoke inhibition of the efflux transporter P-glycoprotein (P-gp) which counteracts the uptake inhibition. As disintegration and dissolution processes are required for the solid dosage form, dissolved naringin may arrive at the site of interaction after talinolol is already absorbed. In conclusion, the effect of nutraceuticals on drug pharmacokinetics can deviate from that observed when administered as food component due to the different dose and dosage form.

  9. Neural activity in the hippocampus predicts individual visual short-term memory capacity.

    PubMed

    von Allmen, David Yoh; Wurmitzer, Karoline; Martin, Ernst; Klaver, Peter

    2013-07-01

    Although the hippocampus had been traditionally thought to be exclusively involved in long-term memory, recent studies raised controversial explanations why hippocampal activity emerged during short-term memory tasks. For example, it has been argued that long-term memory processes might contribute to performance within a short-term memory paradigm when memory capacity has been exceeded. It is still unclear, though, whether neural activity in the hippocampus predicts visual short-term memory (VSTM) performance. To investigate this question, we measured BOLD activity in 21 healthy adults (age range 19-27 yr, nine males) while they performed a match-to-sample task requiring processing of object-location associations (delay period  =  900 ms; set size conditions 1, 2, 4, and 6). Based on individual memory capacity (estimated by Cowan's K-formula), two performance groups were formed (high and low performers). Within whole brain analyses, we found a robust main effect of "set size" in the posterior parietal cortex (PPC). In line with a "set size × group" interaction in the hippocampus, a subsequent Finite Impulse Response (FIR) analysis revealed divergent hippocampal activation patterns between performance groups: Low performers (mean capacity  =  3.63) elicited increased neural activity at set size two, followed by a drop in activity at set sizes four and six, whereas high performers (mean capacity  =  5.19) showed an incremental activity increase with larger set size (maximal activation at set size six). Our data demonstrated that performance-related neural activity in the hippocampus emerged below capacity limit. In conclusion, we suggest that hippocampal activity reflected successful processing of object-location associations in VSTM. Neural activity in the PPC might have been involved in attentional updating.

  10. Short-term hyperoxia does not exert immunologic effects during experimental murine and human endotoxemia

    PubMed Central

    Kiers, Dorien; Gerretsen, Jelle; Janssen, Emmy; John, Aaron; Groeneveld, R.; van der Hoeven, Johannes G.; Scheffer, Gert-Jan; Pickkers, Peter; Kox, Matthijs

    2015-01-01

    Oxygen therapy to maintain tissue oxygenation is one of the cornerstones of critical care. Therefore, hyperoxia is often encountered in critically ill patients. Epidemiologic studies have demonstrated that hyperoxia may affect outcome, although mechanisms are unclear. Immunologic effects might be involved, as hyperoxia was shown to attenuate inflammation and organ damage in preclinical models. However, it remains unclear whether these observations can be ascribed to direct immunosuppressive effects of hyperoxia or to preserved tissue oxygenation. In contrast to these putative anti-inflammatory effects, hyperoxia may elicit an inflammatory response and organ damage in itself, known as oxygen toxicity. Here, we demonstrate that, in the absence of systemic inflammation, short-term hyperoxia (100% O2 for 2.5 hours in mice and 3.5 hours in humans) does not result in increased levels of inflammatory cytokines in both mice and healthy volunteers. Furthermore, we show that, compared with room air, hyperoxia does not affect the systemic inflammatory response elicited by administration of bacterial endotoxin in mice and man. Finally, neutrophil phagocytosis and ROS generation are unaffected by short-term hyperoxia. Our results indicate that hyperoxia does not exert direct anti-inflammatory effects and temper expectations of using it as an immunomodulatory treatment strategy. PMID:26616217

  11. The impact of interference on short-term memory for visual orientation.

    PubMed

    Rademaker, Rosanne L; Bloem, Ilona M; De Weerd, Peter; Sack, Alexander T

    2015-12-01

    Visual short-term memory serves as an efficient buffer for maintaining no longer directly accessible information. How robust are visual memories against interference? Memory for simple visual features has proven vulnerable to distractors containing conflicting information along the relevant stimulus dimension, leading to the idea that interacting feature-specific channels at an early stage of visual processing support memory for simple visual features. Here we showed that memory for a single randomly orientated grating was susceptible to interference from a to-be-ignored distractor grating presented midway through a 3-s delay period. Memory for the initially presented orientation became noisier when it differed from the distractor orientation, and response distributions were shifted toward the distractor orientation (by ∼3°). Interestingly, when the distractor was rendered task-relevant by making it a second memory target, memory for both retained orientations showed reduced reliability as a function of increased orientation differences between them. However, the degree to which responses to the first grating shifted toward the orientation of the task-relevant second grating was much reduced. Finally, using a dichoptic display, we demonstrated that these systematic biases caused by a consciously perceived distractor disappeared once the distractor was presented outside of participants' awareness. Together, our results show that visual short-term memory for orientation can be systematically biased by interfering information that is consciously perceived.

  12. Effects of short-term fasting on energy reserves of vampire bats (Desmodus rotundus).

    PubMed

    Freitas, Mariella B; Passos, Cejana B C; Vasconcelos, Rosângela B; Pinheiro, Eliana C

    2005-01-01

    Studies on metabolic responses to fasting in common vampire bats (Desmodus rotundus) have demonstrated the susceptibility of this species when subjected to long-term fasting. We investigated the effects of short-term fasting (12 h), a period similar to what they face in the field, on their energy reserves. Blood glucose (BG) levels in fed bats were similar to other mammals, but after 12 h without food, these levels were reduced. Plasma lactate and free fatty acids levels in fed bats were higher than in other mammals, although no changes in these levels were detected in response to fasting. Liver glycogen content decreased significantly following fasting. Muscle glycogen, as well as liver and muscle lipid and protein levels, remained unaltered for up to 12 h of fasting. Although BG levels decreased after short-term fasting, body energy reserves do not seem to play an important role for maintenance of glycemic homeostasis during fasting. Despite the decrease in liver glycogen, this small reserve seems insufficient to maintain adequate levels of BG, even during short periods of fasting. Because other reserves were not decreased after fasting, it is possible that the main source of glucose for common vampire bats might be the glucose content of their blood diet.

  13. Microstructural evolution of delta ferrite in SAVE12 steel under heat treatment and short-term creep

    SciTech Connect

    Li, Shengzhi; Eliniyaz, Zumrat; Zhang, Lanting; Sun, Feng; Shen, Yinzhong; Shan, Aidang

    2012-11-15

    This research focused on the formation and microstructural evolution of delta ferrite phase in SAVE12 steel. The formation of delta ferrite was due to the high content of ferrite forming alloy elements such as Cr, W, and Ta. This was interpreted through either JMatPro-4.1 computer program or Cr{sub eq} calculations. Delta ferrite was found in bamboo-like shape and contained large amount of MX phase. It was surrounded by Laves phases before creep or aging treatment. Annealing treatments were performed under temperatures from 1050 Degree-Sign C to 1100 Degree-Sign C and various time periods to study its dissolution kinetics. The result showed that most of the delta ferrite can be dissolved by annealing in single phase austenitic region. Dissolution process of delta ferrite may largely depend on dissolution kinetic factors, rather than on thermodynamic factors. Precipitation behavior during short-term (1100 h) creep was investigated at temperature of 600 Degree-Sign C under a stress of 180 MPa. The results demonstrated that delta ferrite became preferential nucleation sites for Laves phase at the early stage of creep. Laves phase on the boundary around delta ferrite showed relatively slower growth and coarsening rate than that inside delta ferrite. - Highlights: Black-Right-Pointing-Pointer Delta ferrite is systematically studied under heat treatment and short-term creep. Black-Right-Pointing-Pointer Delta ferrite contains large number of MX phase and is surrounded by Laves phases before creep or aging treatment. Black-Right-Pointing-Pointer Formation of delta ferrite is interpreted by theoretical and empirical methods. Black-Right-Pointing-Pointer Most of the delta ferrite is dissolved by annealing in single phase austenitic region. Black-Right-Pointing-Pointer Delta ferrite becomes preferential nucleation sites for Laves phase at the early stage of creep.

  14. SULFURIC ACID REMOVAL PROCESS EVALUATION: SHORT-TERM RESULTS

    SciTech Connect

    Gary M. Blythe; Richard McMillan

    2002-03-04

    results of the short-term tests; the long-term test results will be reported in a later document. The short-term test results showed that three of the four reagents tested, dolomite powder, commercial magnesium hydroxide slurry, and byproduct magnesium hydroxide slurry, were able to achieve 90% or greater removal of sulfuric acid compared to baseline levels. The molar ratio of alkali to flue gas sulfuric acid content (under baseline conditions) required to achieve 90% sulfuric acid removal was lowest for the byproduct magnesium hydroxide slurry. However, this result may be confounded because this was the only one of the three slurries tested with injection near the top of the furnace across from the pendant superheater platens. Injection at the higher level was demonstrated to be advantageous for this reagent over injection lower in the furnace, where the other slurries were tested.

  15. SULFURIC ACID REMOVAL PROCESS EVALUATION: SHORT-TERM RESULTS

    SciTech Connect

    Gary M. Blythe; Richard McMillan

    2002-02-04

    the results of the short-term tests; the long-term test results will be reported in a later document. The short-term test results showed that three of the four reagents tested, dolomite powder, commercial magnesium hydroxide slurry, and byproduct magnesium hydroxide slurry, were able to achieve 90% or greater removal of sulfuric acid compared to baseline levels. The molar ratio of alkali to flue gas sulfuric acid content (under baseline conditions) required to achieve 90% sulfuric acid removal was lowest for the byproduct magnesium hydroxide slurry. However, this result may be confounded because this was the only one of the three slurries tested with injection near the top of the furnace across from the pendant superheater platens. Injection at the higher level was demonstrated to be advantageous for this reagent over injection lower in the furnace, where the other slurries were tested.

  16. Nutritional status in short-term overtraining boxers

    NASA Astrophysics Data System (ADS)

    Alexandrova, Albena; Petrov, Lubomir; Zaekov, Nikolay; Bozhkov, Borislav; Zsheliaskova-Koynova, Zshivka

    2017-03-01

    The diet is essential to the recovery process in athletes, especially those undergoing intensive training. The continuous imbalance between loading and recovery leads to development of overtraining syndrome. The purpose of this study was to establish the changes in the nutritional status of short-term overtrained athletes. Twelve boxers from the team of National Spoils Academy Sofia, Bulgaria during their preparation for the National Championship 2016 were studied. The measurements were conducted three times.in the beginning of preparation (T1), 22 days later (2) and 10 days after (32 days after first measurement), in the beginning of the recovery period, one week prior the competition (T3).The measurements included basic anthropometric data, overtraining questionnaire RESTO-Sport and nutrition questionnaire, plasma concentration of testosterone and cortisol.On the data of dietary survey the percent proportion and the amount of daily consumed proteins, fats and carbohydrates were defined and the energy intake of the tested athletes was calculated. According to the RESTO-Sport a significant decrease in the ratio stress/recovery was observed in the period with the heaviest training load T2, and an increase was estimated in the pre­competition recovery period T3. It was found a typical for the overtraining syndrome decrease in the concentration of testosterone and the ratio of testosterone/cortisol in T3. In some respondents a reduction in carbohydrates and proteins intake was observed in T2 and especially in T3, which correlates with the hormonal changes. In this work the diet changes was discussed as a possible consequence and/or a cause of the overtraining syndrome.

  17. Short Term Effects of Cocoa Consumption on Blood Pressure

    PubMed Central

    Alleyne, T; Alleyne, A; Arrindell, D; Balleram, N; Cozier, D; Haywood, R; Humphrey, C; Pran, L; Rampersad, K; Reyes, D; Bahall, S; Holder, R; Ignacio, D

    2014-01-01

    Hypertension, defined as diastolic pressure ≥ 90 mmHg and systolic pressure ≥ 140 mmHg, is a major cause of morbidity and mortality among black populations globally. Several studies have shown that prolonged consumption of cocoa or cocoa containing products leads to decreased blood pressure (BP) in hypertensives. In this study, we investigated the flavonoid content of the top selling cocoa/cocoa based products in Trinidad and Tobago and attempted to determine if consumption of cocoa had any immediate impact on blood pressure levels. The flavonoid content of three 100% cocoa powder products and four cocoa-based formulas was measured using a modified Folin-Ciocalteu procedure. The brand with the highest flavonoid content, 372 gallic acid equivalents, was selected to evaluate the short-term impact of cocoa consumption on blood pressure. Thirty-six participants comprising nineteen hypertensives and seventeen persons with normal blood pressure had their blood pressure recorded on three separate days using ambulatory blood pressure monitors; the blood pressure was recorded every half hour for eight hours. On the first day, the participants received no intervention but on the second and third days, they received either the intervention (5 g cocoa in 125 ml water) or a placebo, in any order. Statistical analysis conducted using t-test statistic and a 95% confidence interval revealed that whether participants regularly took antihypertensive medication or not, a single intervention of cocoa induced decreases in both the diastolic and systolic BPs that were significant (p = 0.0001). Mean decreases of between 8 mmHg and 18 mmHg were observed. PMID:25429467

  18. Short-Term Wind Power Forecasts using Doppler Lidar

    NASA Astrophysics Data System (ADS)

    Magerman, Beth

    With a ground-based Doppler lidar on the upwind side of a wind farm in the Tehachapi Pass of California, radial wind velocity measurements were collected for repeating sector sweeps, scanning up to 10 kilometers away. This region consisted of complex terrain, with the scans made between mountains. The dataset was utilized for techniques being studied for short-term forecasting of wind power by correlating changes in energy content and of turbulence intensity by tracking spatial variance, in the wind ahead of a wind farm. A ramp event was also captured and its propagation was tracked. Orthogonal horizontal wind vectors were retrieved from the radial velocity using a sector Velocity Azimuth Display method. Streamlines were plotted to determine the potential sites for a correlation of upstream wind speed with wind speed at downstream locations near the wind farm. A "virtual wind turbine" was "placed" in locations along the streamline by using the time-series velocity data at the location as the input to a modeled wind turbine, to determine the extractable energy content at that location. The relationship between this time-dependent energy content upstream and near the wind farm was studied. By correlating the energy content with each upstream location based on a time shift estimated according to advection at the mean wind speed, several fits were evaluated. A prediction of the downstream energy content was produced by shifting the power output in time and applying the best-fit function. This method made predictions of the power near the wind farm several minutes in advance. Predictions were also made up to an hour in advance for a large ramp event. The Magnitude Absolute Error and Standard Deviation are presented for the predictions based on each selected upstream location.

  19. Is Earthquake Prediction Possible from Short-Term Foreshocks?

    NASA Astrophysics Data System (ADS)

    Papadopoulos, Gerassimos; Avlonitis, Markos; Di Fiore, Boris; Minadakis, George

    2015-04-01

    Foreshocks preceding mainshocks in the short-term, ranging from minutes to a few months prior the mainshock, have been known from several decades ago. Understanding the generation mechanisms of foreshocks was supported by seismicity observations and statistics, laboratory experiments, theoretical considerations and simulation results. However, important issues remain open. For example, (1) How foreshocks are defined? (2) Why only some mainshocks are preceded by foreshocks but others do not? (2) Is the mainshock size dependent on some attributes of the foreshock sequence? (3) Is that possible to discriminate foreshocks from other seismicity styles (e.g. swarms, aftershocks)? To approach possible replies to these issues we reviewed about 400 papers, reports, books and other documents referring to foreshocks as well as to relevant laboratory experiments. We found that different foreshock definitions are used by different authors. We found also that the ratio of mainshocks preceded by foreshocks increases with the increase of monitoring capabilities and that foreshock activity is dependent on source mechanical properties and favoured by material heterogeneity. Also, the mainshock size does not depend on the largest foreshock size but rather by the foreshock area. Seismicity statistics may account for an effective discrimination of foreshocks from other seismicity styles since during foreshock activities the seismicity rate increases with the inverse of time and, at the same, the b-value of the G-R relationship as a rule drops significantly. Our literature survey showed that only the last years the seismicity catalogs organized in some well monitored areas are adequately complete to search for foreshock activities. Therefore, we investigated for a set of "good foreshock examples" covering a wide range of mainshock magnitudes from 4.5 to 9 in Japan (Tohoku 2011), S. California, Italy (including L' Aquila 2009) and Greece. The good examples used indicate that foreshocks

  20. Neural circuit mechanisms of short-term memory

    NASA Astrophysics Data System (ADS)

    Goldman, Mark

    Memory over time scales of seconds to tens of seconds is thought to be maintained by neural activity that is triggered by a memorized stimulus and persists long after the stimulus is turned off. This presents a challenge to current models of memory-storing mechanisms, because the typical time scales associated with cellular and synaptic dynamics are two orders of magnitude smaller than this. While such long time scales can easily be achieved by bistable processes that toggle like a flip-flop between a baseline and elevated-activity state, many neuronal systems have been observed experimentally to be capable of maintaining a continuum of stable states. For example, in neural integrator networks involved in the accumulation of evidence for decision making and in motor control, individual neurons have been recorded whose activity reflects the mathematical integral of their inputs; in the absence of input, these neurons sustain activity at a level proportional to the running total of their inputs. This represents an analog form of memory whose dynamics can be conceptualized through an energy landscape with a continuum of lowest-energy states. Such continuous attractor landscapes are structurally non-robust, in seeming violation of the relative robustness of biological memory systems. In this talk, I will present and compare different biologically motivated circuit motifs for the accumulation and storage of signals in short-term memory. Challenges to generating robust memory maintenance will be highlighted and potential mechanisms for ameliorating the sensitivity of memory networks to perturbations will be discussed. Funding for this work was provided by NIH R01 MH065034, NSF IIS-1208218, Simons Foundation 324260, and a UC Davis Ophthalmology Research to Prevent Blindness Grant.