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Sample records for repeated resting exposure

  1. Effect of rest duration on recovery from repeated exercise in near-market-weight pigs.

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    Goumon, S; Brown, J A; Faucitano, L; Bergeron, R; Crowe, T; Connor, M L; Gonyou, H W

    2013-12-01

    The process of transportation can be seen as a succession of stressors, from which pigs may not have time to recover before slaughter. The aim of this study was to determine the extent to which the duration of the rest time given to near-market-weight pigs after an initial exposure to exercise affected their recovery from subsequent exercise. Eighteen groups of 3 gilts were exercised (Ex1) through a standard handling course, including two 19° ramps, and then were held in a holding pen for either 35 (RT35), 75 (RT75), or 150 (RT150) min (Rest Period 1, RP1). Afterward, pigs were exercised a second time (Ex2) and left to rest for 150 min. Recovery from Ex2 (Rest Period 2, RP2) was assessed using measures of heart rate (HR), respiratory rate (RR), skin temperature (ST), and posture. Repeated measures and regression analysis were used to analyze the data. For RT75 pigs, there were no detrimental effects of Ex2 on HR, RR, and handling time (P > 0.05, for all) during the exercise and recovery periods. Skin temperature during Ex2 was greater than ST during Ex1 (P 0.05). Doubling the rest period did not provide any more beneficial effects in regard to RR and HR (P > 0.05 for both) during Ex2 and RP2 compared to RT75 pigs, as shown by the similar latencies to recover for these 2 variables. However, ST did not increase between exercises, and RT150 pigs required less time to complete the handling course during Ex2. The results show that a lack of rest after an initial exposure to exercise made pigs more susceptible to stress during Ex2 and RP2, as demonstrated by greater (P rest during RP2, RT35 pigs eventually recovered. Latencies of recovery for HR, ST, RR, and posture were all greater (P rest to recover from exercise, a subsequent exposure to the same exercise will cause an increase in these physiological variables during exercise and recovery. Further research is needed to investigate factors contributing to the quality of rest, with a particular focus on conditions not

  2. Altering Work to Rest Ratios Differentially Influences Fatigue Indices During Repeated Sprint Ability Testing.

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    La Monica, Michael B; Fukuda, David H; Beyer, Kyle S; Hoffman, Mattan W; Miramonti, Amelia A; Riffe, Josh J; Baker, Kayla M; Fragala, Maren S; Hoffman, Jay R; Stout, Jeffrey R

    2016-02-01

    This study examined the influence of recovery time on fatigue indices, performance (total work [TW], peak power [PP], and mean power [MP]), and oxygen consumption during repeated sprint ability (RSA) on a cycle ergometer. Eight recreationally-trained men performed 3 RSA protocols consisting of 10 × 6 s sprints with 12 s, 18 s, and 24 s rest intervals between each sprint. Fatigue indices were determined as percent decrement (%Dec) and rate of decline using either a log transform method or standard slope approach for TW, PP, and MP during respective RSA protocols. The maximal VO2 value in response to given sprint intervals and the minimal VO2 value in response to given rest periods (VO2 work and VO2 rest, respectively) were recorded. A repeated measures analysis of variance was used to analyze all variables. Average VO2 work was not different among rest interval trials. Average VO2 rest with 12 s rest was greater than 18 s and 24 s (2.16 ± 0.17 L · min(-1), 1.91 ± 0.18 L · min(-1), 1.72 ± 0.15 L · min(-1), respectively), while 18 s was greater than 24 s. Average TW and MP were greater with 24 s rest than 12 s (4,604.44 ± 915.98 J vs. 4,305.46 ± 727.17 J, respectively), with no differences between RSA protocols for PP. No differences in %Dec were observed. Both methods of calculating rates of decline per sprint for PP and TW were greater during 12 s than 18 s or 24 s. Since changes were only noted between the 12 s and 24 s protocols, a 6 s differential in rest intervals may not be enough to elicit alterations in TW, PP, MP, or %Dec in RSA performance. Rate of decline may be a more sensitive measure of fatigue than %Dec.

  3. Modeling repeated measurement data for occupational exposure assessment and epidemiology

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    Peretz, Chava

    2004-01-01

    Repeated measurements designs, occur frequently in the assessment of exposure to toxic chemicals. This thesis deals with the possibilities of using mixed effects models for occupational exposure assessment and in the analysis of exposure response relationships. The model enables simultaneous estima

  4. The optimal exercise to rest ratios in repeated sprint ability training in youth soccer players.

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    Ruscello, Bruno; Partipilo, Filippo; Pantanella, Laura; Esposito, Mario; D'Ottavio, Stefano

    2016-12-01

    The aim of this study was to investigate the applicability of three different exercise to rest ratios in RSA training in youth soccer players, applying those ones already adopted in adult players, when performing three different sprinting modes (straight, shuttle and sprinting with changing of direction). Eighteen young trained male soccer players (Height: 1.66±0.07 m; weight: 58.22±7.64 kg; BMI 19.37±3.42 kg·m-2; age:14 years) participated to the study. In order to compare the different values of the time recorded, a Fatigue Index (FI) was used. Recovery times among trials in the sets were administered according to the 1:5, 1:3; 1:2 exercise to rest ratio, respectively. Significant differences among trials within each set (Repeated Measures Anova; Psprinting modalities when applying the investigated exercise to rest ratios (Factorial Anova; between; P>0.05). The results of this study confirm that the exercise to rest ratios considered in this study might be suitable to design effective testing protocols and training sessions aimed at the development of the RSA in youth soccer players, keeping the performances in the speed domain (FI%< ≈7-8%) but inducing the fatigue processes sought with this kind of training method.

  5. Evaluation of critical rest interval determined from repeated sprint ability testing.

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    LA Monica, Michael B; Fukuda, David H; Beyer, Kyle S; Hoffman, Mattan W; Miramonti, Amelia A; Fragala, Maren S; Stout, Jeffrey R; Hoffman, Jay R

    2016-10-01

    To test if the critical power (CP) concept can be utilized to determine the critical rest interval (CRI) using repeated sprint ability (RSA) testing with varying work-to-rest ratios. Twelve recreationally trained men (mean±SD; age 24.1±3.6 years) completed a graded exercise test and three RSA protocols with 6-second maximal sprints and varying rest intervals (12-36 s) on a cycle ergometer to determine CRI. Intermittent critical power (ICP) was calculated through the linear total work (TW) and time-to-exhaustion (TTE) relationship, whereas CRI was estimated using average work per sprint and ICP. Validation trials above and below CRI were conducted to evaluate physiological response. Repeated measures analysis of variance were used to analyze variables from RSA trials and changes in blood lactate, oxygen uptake (V̇O2), heart rate (HR), peak power, and TW throughout the validation trials. Blood lactate, average V̇O2, V̇O2peak, and heart rate were significantly greater below CRI (8.94±4.89 mmol/L, 2.05±0.36 L/min, 2.84±0.48 L/min, and 151.14±18.46 bpm, respectively) when compared to above CRI (6.56±3.45 mmol/L, 1.78±0.26 L/min, 2.61±0.43 L/min, and 138.14±17.51 bpm). Significant interactions were found between above and below CRI for minimal V̇O2 response and maximal HR response, which were consistent with the heavy and severe exercise intensity domains. The use of the work-time relationship determined from RSA testing with varying rest intervals can be used to determine CRI and may distinguish between physiological responses related to exercise intensity domains.

  6. Short- or long-rest intervals during repeated-sprint training in soccer?

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    Iaia, F Marcello; Fiorenza, Matteo; Larghi, Luca; Alberti, Giampietro; Millet, Grégoire P; Girard, Olivier

    2017-01-01

    The present study compared the effects of two repeated-sprint training (RST) programs, differing in duration of the between-sprint rest intervals, on various soccer-related exercise performances. For 5 weeks during the competitive season, twenty-nine young trained male soccer players either replaced two of their habitual fitness conditioning sessions with RST characterized by short (5-15; n = 9) or long (5-30; n = 10) rest intervals, or served as control (n = 10). The 5-15 and 5-30 protocols consisted of 6 repetitions of 30-m (~5 s) straight-line sprints interspersed with 15 s or 30 s of passive recovery, respectively. 5-15 improved 200-m sprint time (2.0±1.5%; psprint performance, whereas 5-30 lowered the 20-m sprint time (2.7±1.6%; psprint performance. The distance covered during the Yo-Yo Intermittent Recovery Test Level 2 increased following 5-15 (11.4±5.0%; prepeated-sprint ability test were possibly greater following 5-30 (3.6±0.9%; prepeated-sprint ability test as well as in blood lactate concentration during submaximal exercise (17-18%). No changes occurred in the control group. In soccer players, RST over a 5-week in-season period is an efficient means to simultaneously develop different components of fitness relevant to match performance, with different benefits induced by shorter compared to longer rest intervals.

  7. Short- or long-rest intervals during repeated-sprint training in soccer?

    Science.gov (United States)

    Iaia, F. Marcello; Fiorenza, Matteo; Larghi, Luca; Alberti, Giampietro; Millet, Grégoire P.; Girard, Olivier

    2017-01-01

    The present study compared the effects of two repeated-sprint training (RST) programs, differing in duration of the between-sprint rest intervals, on various soccer-related exercise performances. For 5 weeks during the competitive season, twenty-nine young trained male soccer players either replaced two of their habitual fitness conditioning sessions with RST characterized by short (5–15; n = 9) or long (5–30; n = 10) rest intervals, or served as control (n = 10). The 5–15 and 5–30 protocols consisted of 6 repetitions of 30-m (~5 s) straight-line sprints interspersed with 15 s or 30 s of passive recovery, respectively. 5–15 improved 200-m sprint time (2.0±1.5%; psoccer players, RST over a 5-week in-season period is an efficient means to simultaneously develop different components of fitness relevant to match performance, with different benefits induced by shorter compared to longer rest intervals. PMID:28199402

  8. The effect of rest periods on temporary threshold shift (TTS) after noise exposure

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    Nilsson, R.

    1991-12-01

    In a series of experimental studies the hypothesis that periods of silence reduce the risk of hearing impairment was tested. The noise exposure was comparable to that of workers in the engineering industry: e.g., during 10 minutes' grinding. Two different experiments with rest periods of different lengths and repetition rates were performed. Frequent short periods of silence offered the best protection. Significantly less influence on hearing, temporary threshold shift (TTS), was obtained when repeated 5-second pauses were allowed than during continuous work. The studies also included experiments with impulse noise. This consisted of a different series of sledgehammer impacts, with a peak level of 130 dB(A). Different repetition rates were tested in order to determine whether the reaction time of the acoustic reflex influenced its protective effect. A low repetition rate gave less temporary impairment than a higher repetition rate, although the total number of impacts was the same.

  9. Physiological consequences of repeated exposures to conditioned fear.

    Science.gov (United States)

    Thompson, Robert S; Strong, Paul V; Fleshner, Monika

    2012-06-01

    Activation of the stress response evokes a cascade of physiological reactions that may be detrimental when repeated or chronic, and when triggered after exposure to psychological/emotional stressors. Investigation of the physiological mechanisms responsible for the health damaging effects requires animal paradigms that repeatedly evoke a response to psychological/emotional stressors. To this end, adult male Sprague Dawley rats were repeatedly exposed (2X per day for 20 days) to a context that they were conditioned to fear (conditioned fear test, CFT). Repeated exposure to CFT produced body weight loss, adrenal hypertrophy, thymic involution, and basal corticosterone elevation. In vivo biotelemetry measures revealed that CFT evokes sympathetic nervous system driven increases in heart rate (HR), mean arterial pressure (MAP), and core body temperature. Extinction of behavioral (freezing) and physiological responses to CFT was prevented using minimal reinstatement footshock. MAP responses to the CFT did not diminish across 20 days of exposure. In contrast, HR and cardiac contractility responses declined by day 15, suggesting a shift toward vascular-dominated MAP (a pre-clinical marker of CV dysfunction). Flattened diurnal rhythms, common to stress-related mood/anxiety disorders, were found for most physiological measures. Thus, repeated CFT produces adaptations indicative of the health damaging effects of psychological/emotional stress.

  10. Physiological Consequences of Repeated Exposures to Conditioned Fear

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    Robert S. Thompson

    2012-05-01

    Full Text Available Activation of the stress response evokes a cascade of physiological reactions that may be detrimental when repeated or chronic, and when triggered after exposure to psychological/emotional stressors. Investigation of the physiological mechanisms responsible for the health damaging effects requires animal paradigms that repeatedly evoke a response to psychological/emotional stressors. To this end, adult male Sprague Dawley rats were repeatedly exposed (2X per day for 20 days to a context that they were conditioned to fear (conditioned fear test, CFT. Repeated exposure to CFT produced body weight loss, adrenal hypertrophy, thymic involution, and basal corticosterone elevation. In vivo biotelemetry measures revealed that CFT evokes sympathetic nervous system driven increases in heart rate (HR, mean arterial pressure (MAP, and core body temperature. Extinction of behavioral (freezing and physiological responses to CFT was prevented using minimal reinstatement footshock. MAP responses to the CFT did not diminish across 20 days of exposure. In contrast, HR and cardiac contractility responses declined by day 15, suggesting a shift toward vascular-dominated MAP (a pre-clinical marker of CV dysfunction. Flattened diurnal rhythms, common to stress-related mood/anxiety disorders, were found for most physiological measures. Thus, repeated CFT produces adaptations indicative of the health damaging effects of psychological/emotional stress.

  11. Repeated trauma exposure does not impair distress reduction during imaginal exposure for posttraumatic stress disorder.

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    Jerud, Alissa B; Farach, Frank J; Bedard-Gilligan, Michele; Smith, Hillary; Zoellner, Lori A; Feeny, Norah C

    2017-08-01

    Based on experimental research on threat extinction, individuals exposed to repeated traumatic events may have impaired outcome in exposure therapy compared to those who have experienced a single trauma (Lang & McTeague, ). This study examined whether repeated trauma exposure predicts smaller changes in self-reported distress during imaginal exposure and worse outcomes for patients with posttraumatic stress disorder (PTSD). Adults (N = 116) with chronic PTSD received up to 10 sessions of prolonged exposure (PE) therapy. Trauma exposure was assessed via interview and number of traumatic events were summed for each participant. To examine reductions in distress during treatment, mean and peak values of distress during imaginal exposure were calculated for the first imaginal session (initial distress activation) and subsequent sessions (between-session change in distress). Change in PTSD symptoms from pre- to posttreatment and follow-up provided an additional index of outcome. In-session distress during imaginal exposure decreased over the course of treatment. PTSD symptoms also decreased over treatment, with gains being maintained through follow-up. Repeated trauma exposure was not significantly correlated with initial distress activation. Additionally, linear mixed-model analyses showed no significant association between repeated trauma exposure and between-session change in distress or PTSD symptoms. Contrary to recent speculation, repeated trauma exposure did not predict less change in self-reported distress during imaginal exposure or worse PTSD outcomes. The bench-to-bedside linkage of threat extinction to exposure therapy is discussed, noting strengths and weaknesses. Patients with repeated trauma exposure show reductions in distress with exposure treatment and benefit from PE as much as patients with single-exposure trauma histories. © 2016 Wiley Periodicals, Inc.

  12. Cataract after repeated daily in vivo exposure to ultraviolet radiation.

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    Galichanin, Konstantin; Löfgren, Stefan; Söderberg, Per

    2014-12-01

    Epidemiological data indicate a correlation between lifelong exposure to ultraviolet radiation and cortical cataract. However, there is no quantitative experimental data on the effect of daily repeated in vivo exposures of the eye to UVR. Therefore, this experiment was designed to verify whether the dose additivity for UVR exposures holds through periods of time up to 30 d. Eighty rats were conditioned to a rat restrainer 5 d prior to exposure. All animals were divided into four exposure period groups of 1, 3, 10, and 30 d of exposure to UVR. Each exposure period group of 20 animals was randomly divided into five cumulated UVR dose subgroups. Eighteen-wk-old non-anesthetized albino Sprague-Dawley rats were exposed daily to UVR-300 nm for 15 min. One week after the last exposure, animals were sacrificed. The lenses were extracted for macroscopic imaging of dark-field anatomy, and degree of cataract was quantified by measurement of the intensity of forward lens light scattering. Maximum tolerable dose (MTD(2.3:16)), a statistically defined standard for sensitivity for the threshold for UVR cataract, was estimated for each exposure period. Exposed lenses developed cataract with varying appearance on the anterior surface. Single low doses of UVR accumulated to cause cataract during periods up to 30 d. MTD(2.3:16) for 1, 3, 10, and 30 d of repeated exposures was estimated to 4.70, 4.74, 4.80, and 6.00 kJ m(-2), respectively. In conclusion, the lens sensitivity to UVR-B for 18-wk-old Sprague-Dawley rats decreases with the increasing number of days being exposed.

  13. Hippocampal ER stress and learning deficits following repeated pyrethroid exposure.

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    Hossain, Muhammad M; DiCicco-Bloom, Emanuel; Richardson, Jason R

    2015-01-01

    Endoplasmic reticulum (ER) stress is implicated as a significant contributor to neurodegeneration and cognitive dysfunction. Previously, we reported that the widely used pyrethroid pesticide deltamethrin causes ER stress-mediated apoptosis in SK-N-AS neuroblastoma cells. Whether or not this occurs in vivo remains unknown. Here, we demonstrate that repeated deltamethrin exposure (3 mg/kg every 3 days for 60 days) causes hippocampal ER stress and learning deficits in adult mice. Repeated exposure to deltamethrin caused ER stress in the hippocampus as indicated by increased levels of C/EBP-homologous protein (131%) and glucose-regulated protein 78 (96%). This was accompanied by increased levels of caspase-12 (110%) and activated caspase-3 (50%). To determine whether these effects resulted in learning deficits, hippocampal-dependent learning was evaluated using the Morris water maze. Deltamethrin-treated animals exhibited profound deficits in the acquisition of learning. We also found that deltamethrin exposure resulted in decreased BrdU-positive cells (37%) in the dentate gyrus of the hippocampus, suggesting potential impairment of hippocampal neurogenesis. Collectively, these results demonstrate that repeated deltamethrin exposure leads to ER stress, apoptotic cell death in the hippocampus, and deficits in hippocampal precursor proliferation, which is associated with learning deficits.

  14. Effects of acute electromagnetic fields exposure on the interhemispheric homotopic functional connectivity during resting state.

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    Lv, Bin; Shao, Qing; Chen, Zhiye; Ma, Lin; Wu, Tongning

    2015-08-01

    In this paper, we aimed to investigate the possible effects of acute radiofrequency electromagnetic fields (EMF) on the interhemispheric homotopic functional connectivity with resting state functional magnetic resonance imaging (fMRI) technique. We designed a controllable LTE-related EMF exposure environment at 2.573 GHz and performed the 30 min real/sham exposure experiments on human brain under the safety limits. The resting state fMRI signals were collected before and after EMF exposure. Then voxel-mirrored homotopic connectivity method was utilized to evaluate the acute effects of LTE EMF exposure on the homotopic functional connectivity between two human hemispheres. Based on our previous research, we further demonstrated that the 30 min short-term LTE EMF exposure would modulate the interhemispheric homotopic functional connectivity in resting state around the medial frontal gyrus and the paracentral lobule during the real exposure.

  15. Influence of repeated daily menthol exposure on human temperature regulation and perception.

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    Gillis, D Jason; Weston, Neil; House, James R; Tipton, Michael J

    2015-02-01

    A single exposure to menthol can, depending on concentration, enhance both cool sensations and encourage body heat storage. This study tested whether there is an habituation in either response after repeated-daily exposures. Twenty-two participants were assigned to one of three spray groups: Control (CON; n=6), 0.05% L-menthol (M(0.05%); n=8), and 0.2% L-menthol (M(0.2%); n=8). On Monday (20°C, 50% rh) participants were sprayed with 100 mL of solution and undertook 40 min of cycling at 45% of their peak power (Ex1), from Tuesday to Thursday (30°C, 50% rh) they were sprayed twice daily whilst resting (R1 to R6), Friday was a repeat of Monday (Ex2). Thermal sensation (TS), thermal comfort, perceived exertion, irritation, rectal and skin temperature (Tsk), skin blood flow (SkBF) and sweat rate were monitored. A two-way ANOVA (alpha=0.05) compared responses from the beginning (Ex1, R1) and end (Ex2, R5) of the testing week. M(0.2%) induced significantly (PMenthol caused a heat storage response, mediated by vasoconstriction, at the beginning and end of the week, suggesting the habituation of TS occurred in a pathway specific to sensation. In summary, the cooling influence of 0.2% menthol habituates after repeated-daily exposures, but with no habituation in heat storage.

  16. Acute versus repeated chocolate exposure: effects on intake and cravings in restrained and unrestrained eaters.

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    Coelho, Jennifer S; Nederkoorn, Chantal; Jansen, Anita

    2014-04-01

    The cue-reactivity model, which is based on conditioning processes, posits that repeated food exposure (in the absence of consumption) should decrease cue reactivity. To examine whether repeated chocolate exposure attenuates cravings and intake, relative to those exposed to an acute cue, a 2 (repeated vs acute cue) × 2 (restrained vs unrestrained eaters) design was employed. Fifty female participants were recruited. Repeated exposure reduced cravings in unrestrained eaters (relative to acute exposure), but increased cravings in restrained eaters. An interaction between restraint and exposure emerged on intake, such that restrained eaters ate less after acute exposure than did unrestrained eaters.

  17. Inhalation exposure system used for acute and repeated-dose methyl isocyanate exposures of laboratory animals.

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    Adkins, B; O'Connor, R W; Dement, J M

    1987-06-01

    Laboratory animals were exposed by inhalation for 2 hr/day (acute) or 6 hr/day (four consecutive days, repeated dose) to methyl isocyanate (MIC). Exposures were conducted in stainless steel and glass inhalation exposure chambers placed in stainless steel, wire mesh cages. MIC was delivered with nitrogen via stainless steel and Teflon supply lines. Chamber concentrations ranged from 0 to 60 ppm and were monitored continuously with infrared spectrophotometers to 1 ppm and at 2-hr intervals to 20 ppb with a high performance liquid chromatograph equipped with a fluorescence detector. Other operational parameters monitored on a continuous basis included chamber temperature (20-27 degrees C), relative humidity (31-64%), static (transmural) pressure (-0.3 in.), and flow (300-500 L/min). The computer-assistance system interfaced with the inhalation exposure laboratory is described in detail, including the analytical instrumentation calibration system used throughout this investigation.

  18. URINARY CREATINE AT REST AND AFTER REPEATED SPRINTS IN ATHLETES: A PILOT STUDY

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    I. Bezrati-Benayed

    2014-07-01

    Full Text Available Creatine plays a key role in muscle function and its evaluation is important in athletes. In this study, urinary creatine concentration was measured in order to highlight its possible significance in monitoring sprinters. The study included 51 sprinters and 25 age- and sex-matched untrained subjects as a control group. Body composition was measured and dietary intake estimated. Urine samples were collected before and after standardized physical exercise. Creatine was assessed by gas chromatography mass spectrometry. Basal urinary creatine (UC was significantly lower in sprinters than controls (34±30 vs. 74±3 μmol/mmol creatinine, p<0.05. UC was inversely correlated with body mass (r=-0.34, p<0.01 and lean mass (r=- 0.30, p<0.05, and positively correlated with fat mass (r=0.32, p<0.05. After acute exercise, urinary creatine significantly decreased in both athletes and controls. UC is low in sprinters at rest and further decreases after exercise, most likely due to a high uptake and use of creatine by muscles, as muscle mass and physical activity are supposed to be greater in athletes than untrained subjects. Further studies are needed to test the value of urinary creatine as a non-invasive marker of physical condition and as a parameter for managing Cr supplementation in athletes.

  19. Urinary creatine at rest and after repeated sprints in athletes: a pilot study.

    Science.gov (United States)

    Bezrati-Benayed, I; Nasrallah, F; Feki, M; Chamari, K; Omar, S; Alouane-Trabelsi, L; Ben Mansour, A; Kaabachi, N

    2014-03-01

    Creatine plays a key role in muscle function and its evaluation is important in athletes. In this study, urinary creatine concentration was measured in order to highlight its possible significance in monitoring sprinters. The study included 51 sprinters and 25 age- and sex-matched untrained subjects as a control group. Body composition was measured and dietary intake estimated. Urine samples were collected before and after standardized physical exercise. Creatine was assessed by gas chromatography mass spectrometry. Basal urinary creatine (UC) was significantly lower in sprinters than controls (34±30 vs. 74±3 µmol/mmol creatinine, p sprinters at rest and further decreases after exercise, most likely due to a high uptake and use of creatine by muscles, as muscle mass and physical activity are supposed to be greater in athletes than untrained subjects. Further studies are needed to test the value of urinary creatine as a non-invasive marker of physical condition and as a parameter for managing Cr supplementation in athletes.

  20. The Effects of Repeated Exposure to Graphic Fear Appeals on Cigarette Packages: A Field Experiment

    NARCIS (Netherlands)

    Dijkstra, A.; Bos, C.

    2015-01-01

    Experimental studies on the effects of graphic fear appeals on cigarette packages typically expose smokers in a single session to a fear appeal, although in practice the exposure is always repeated. The present study applied an improved study design with repeated exposure to fear appeals on cigarett

  1. The Effects of Repeated Exposure to Graphic Fear Appeals on Cigarette Packages : A Field Experiment

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    Dijkstra, Arie; Colin, Bos,

    2015-01-01

    Experimental studies on the effects of graphic fear appeals on cigarette packages typically expose smokers in a single session to a fear appeal, although in practice the exposure is always repeated. The present study applied an improved study design with repeated exposure to fear appeals on cigarett

  2. The Effects of Repeated Exposure to Graphic Fear Appeals on Cigarette Packages : A Field Experiment

    NARCIS (Netherlands)

    Dijkstra, Arie; Colin, Bos,

    2015-01-01

    Experimental studies on the effects of graphic fear appeals on cigarette packages typically expose smokers in a single session to a fear appeal, although in practice the exposure is always repeated. The present study applied an improved study design with repeated exposure to fear appeals on

  3. The Effects of Repeated Exposure to Graphic Fear Appeals on Cigarette Packages: A Field Experiment

    NARCIS (Netherlands)

    Dijkstra, A.; Bos, C.

    2015-01-01

    Experimental studies on the effects of graphic fear appeals on cigarette packages typically expose smokers in a single session to a fear appeal, although in practice the exposure is always repeated. The present study applied an improved study design with repeated exposure to fear appeals on

  4. Dealing with Consumer Differences in Liking during Repeated Exposure to Food; Typical Dynamics in Rating Behavior

    NARCIS (Netherlands)

    Dalenberg, Jelle R.; Nanetti, Luca; Renken, Remco J.; de Wijk, Rene A.; ter Horst, Gert J.

    2014-01-01

    Consumers show high interindividual variability in food liking during repeated exposure. To investigate consumer liking during repeated exposure, data is often interpreted on a product level by averaging results over all consumers. However, a single product may elicit inconsistent behaviors in

  5. Attenuated response to repeated daily ozone exposures in asthmatic subjects

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    Gong, H. Jr.; Linn, W.S. [Rancho Low Amigos Medical Center, Downey, CA (United States); McManus, M.S. [Univ. of California, Los Angeles, CA (United States)

    1997-01-01

    The development of attenuated response ({open_quotes}tolerance{close_quotes}) to daily ozone (O{sub 3}) exposures in the laboratory is well established in healthy adult volunteers. However, the capability of asthmatics to develop tolerance during multiday ozone exposures in unclear. We exposed 10 adult volunteers with mild asthma to 0.4 ppm O{sub 3} in filtered air for 3 h/d on 5 consecutive d. Two similar filtered-air exposures during the preceding week served as controls. Follow-up O{sub 3} exposures were performed 4 and 7 d after the most recent consecutive exposure. All exposures were performed in an environmental chamber at 31 {degrees}C and 35% relative humidity. The subjects performed moderate exercise (mean ventilation rate of 32 l/min) for 15 min of each half-hour. Responses were measured with spirometry and symptom evaluations before and after each exposure, and a bronchial reactivity test (methacholine challenge) was conducted after each exposure. All response measurements showed clinically and statistically significant day-to-day variation. Symptom and forced-expiratory-volume-in-1-s responses were similarly large on the 1st and 2nd O{sub 3} exposure days, after which they diminished progressively, approaching filtered air response levels by the 5th consecutive O{sub 3} day. This tolerance was partially lost 4 and 7 d later. Bronchial reactivity peaked after the first O{sub 3} exposure and remained somewhat elevated after all subsequent O{sub 3} exposures, relative to its control level following filtered-air exposures. Individual responses varied widely; more severe initial responses to O{sub 3} predicted less rapid attenuation. We concluded that asthmatics can develop tolerance to frequent high-level O{sub 3} exposures in much the same manner as normal subjects, although the process may be slower and less fully effective in asthmatics. 27 refs., 3 figs., 4 tabs.

  6. Lens opacities after repeated exposure to ultraviolet radiation.

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    Michael, R; Löfgren, S; Söderberg, P G

    1999-12-01

    To investigate the effect of the interval between two, near-threshold exposures to ultraviolet radiation (UVR) on cataract development. One eye of Sprague-Dawley rats was exposed twice to 4 kJ/m2 narrow band UVR (lambdaMAX=300 nm) for 15 min each. The interval between exposures was 0, 6, 24 or 48 h. One week after the first exposure both lenses were removed for photography and measurement of the intensity of forward light scattering to quantify lens opacities. All exposed lenses developed cataract. Forward light scattering was the same after double exposure with no interval or a 6 h interval. Forward light scattering after a 24 or 48 h interval was nearly twofold greater than that following no interval or a 6 h interval. The exposed lenses in all groups had mild anterior surface opacities and intense equatorial opacities as judged with a stereomicroscope. Two, near-threshold UVR exposures at 0 or a 6 h interval produce the same degree of lens opacification. When the second exposure follows 24 or 48 h after the first, lenticular damage increases. Repair processes between 24 and 48 h after exposure appear to be sensitive to UVR, and an additional exposure during this time may aggravate cataract development.

  7. Positive affective interactions: The role of repeated exposure and copresence

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    Shahid, S.; Krahmer, E.; Neerincx, M.; Swerts, M.

    2013-01-01

    We describe and evaluate a new interface to induce positive emotions in users: a digital, interactive adaptive mirror. We study whether the induced affect is repeatable after a fixed interval (Study 1) and how copresence influences the emotion induction (Study 2). Results show that participants syst

  8. Effects of hyperlipidemia on adaptive responses to repeated zinc exposure

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    In individuals with underlying atherosclerosis and coronary heart disease (CHD), exposure to near-road air pollution correlates epidemiologically with deleterious health outcome. Associated cardiotoxicity purportedly involves generation of reactive oxygen species (ROS) and activa...

  9. Repeated exposure to conditioned fear stress increases anxiety and delays sleep recovery following exposure to an acute traumatic stressor

    Directory of Open Access Journals (Sweden)

    Benjamin N Greenwood

    2014-10-01

    Full Text Available Repeated stressor exposure can sensitize physiological responses to novel stressors and facilitate the development of stress-related psychiatric disorders including anxiety. Disruptions in diurnal rhythms of sleep-wake behavior accompany stress-related psychiatric disorders and could contribute to their development. Complex stressors that include fear-eliciting stimuli can be a component of repeated stress experienced by humans, but whether exposure to repeated fear can prime the development of anxiety and sleep disturbances is unknown. In the current study, adult male F344 rats were exposed to either control conditions or repeated contextual fear conditioning for 22 days followed by exposure to either no, mild (10, or severe (100 acute uncontrollable tail shock stress. Exposure to acute stress produced anxiety-like behavior as measured by a reduction in juvenile social exploration and exaggerated shock-elicited freezing in a novel context. Prior exposure to repeated fear enhanced anxiety-like behavior as measured by shock-elicited freezing, but did not alter social exploratory behavior. The potentiation of anxiety produced by prior repeated fear was temporary; exaggerated fear was present 1 day but not 4 days following acute stress. Interestingly, exposure to acute stress reduced REM and NREM sleep during the hours immediately following acute stress. This initial reduction in sleep was followed by robust REM rebound and diurnal rhythm flattening of sleep / wake behavior. Prior repeated fear extended the acute stress-induced REM and NREM sleep loss, impaired REM rebound, and prolonged the flattening of the diurnal rhythm of NREM sleep following acute stressor exposure. These data suggest that impaired recovery of sleep / wake behavior following acute stress could contribute to the mechanisms by which a history of prior repeated stress increases vulnerability to subsequent novel stressors and stress-related disorders.

  10. Effects of repeated skin exposure to low nickel concentrations

    DEFF Research Database (Denmark)

    Nielsen, N H; Menné, T; Kristiansen, J

    1999-01-01

    and nickel allergy, either on normal or on SLS-treated forearm skin. The present study strongly suggests that the changes observed were specific to nickel exposure. Standardized methods to assess trace to moderate nickel exposure on the hands, and the associated effects in nickel-sensitized subjects...... with a group of patients who immersed a finger into water. The nickel concentrations used also provoked significant inflammatory skin changes on sodium lauryl sulphate (SLS)-treated forearm skin of the patients, whereas inflammatory skin changes were not observed in healthy volunteers without hand eczema...

  11. Sensitization and Tolerance Following Repeated Exposure to Caffeine and Alcohol in Mice

    Science.gov (United States)

    May, Christina E.; Haun, Harold L.; Griffin, William C.

    2015-01-01

    Introduction Energy drinks are popular mixers with alcohol. While energy drinks contain many ingredients, caffeine is an important pharmacologically active component and is generally present in larger amounts than in other caffeinated beverages. In these studies, we investigated the hypothesis that caffeine would influence the effects of alcohol (ethanol) on conditioned taste aversion, ataxia and locomotor activity after repeated exposure. Methods Four groups of mice were exposed by oral gavage twice daily to vehicle, ethanol (4 g/kg), caffeine (15 mg/kg), or the ethanol/caffeine combination. Conditioned taste aversion to saccharin and ataxia in the parallel rod task were evaluated after 8 or 16 gavages, respectively, using ethanol (1–3 g/kg) or ethanol/caffeine (3mg/kg + 2 g/kg) challenges. In addition, locomotor activity was evaluated initially and after repeated exposure to oral gavage of these drugs and doses. Results Repeated oral gavage of ethanol produced significant locomotor sensitization, with those mice increasing total distance traveled by 2-fold. The locomotor response to caffeine, while significantly greater than vehicle gavage, did not change with repeated exposure. On the other hand, repeated gavage of caffeine/ethanol combination produced a substantial increase in total distance traveled after repeated exposure (~4-fold increase). After repeated ethanol exposure, there was significant tolerance to ethanol in the conditioned taste aversion and parallel rod tests. However, neither a history of caffeine exposure nor including caffeine influenced ethanol-induced conditioned taste aversion. Interestingly, a history of caffeine exposure increased the ataxic response to the caffeine/ethanol combination and appeared to reduce the ataxic response to high doses of ethanol. Conclusion The data support the general hypothesis that repeated exposure to caffeine influences the response to ethanol. Together with previously published work, these data indicate

  12. Repeated successful induction of fertility after replacing hydrocortisone with dexamethasone in a patient with congenital adrenal hyperplasia and testicular adrenal rest tumors.

    NARCIS (Netherlands)

    Claahsen-van der Grinten, H.L.; Otten, B.J.; Sweep, C.G.J.; Hermus, A.R.M.M.

    2007-01-01

    OBJECTIVE: To report repeated successful induction of fertility in an adult male patient with congenital adrenal hyperplasia (CAH) and testicular adrenal rest tumors (TART). DESIGN: Case report. SETTING: Radboud University Nijmegen Medical Centre. PATIENT(S): A 23-year-old male CAH patient with bila

  13. Within-session effect of repeated stress exposure on extinction circuitry function in social anxiety disorder.

    Science.gov (United States)

    Åhs, Fredrik; Gingnell, Malin; Furmark, Tomas; Fredrikson, Mats

    2017-03-30

    Anxiety reduction following repeated exposure to stressful experiences is generally held to depend on neural processes involved in extinction of conditioned fear. We predicted that repeated exposure to stressful experiences would change activity throughout the circuitry serving extinction, including ventromedial prefrontal cortex (vmPFC), the hippocampus and the amygdala. To test this prediction, 36 participants diagnosed with SAD performed two successive speeches in front of an observing audience while regional cerebral blood flow (rCBF) was recorded using positron emission tomography. To control for non-anxiolytic effects of repeated exposure, rCBF was also measured during repeated presentations of neutral and angry facial expressions. Results showed that anxiety ratings and heart rate decreased from the first to the second speech, indicating an anxiolytic effect of repeated exposure. Exposure attenuated rCBF in the amygdala whereas no change in rCBF was observed in the vmPFC or hippocampus. The rCBF-reductions in the amygdala were greater following repetition of the speech task than repetition of face exposure indicating that they were specific to anxiety attenuation and not due to a reduced novelty. Our findings suggest that amygdala-related attenuation processes are key to understanding the working mechanisms of exposure therapy.

  14. Striatal dopamine dynamics in mice following acute and repeated toluene exposure.

    Science.gov (United States)

    Apawu, Aaron K; Mathews, Tiffany A; Bowen, Scott E

    2015-01-01

    The abused inhalant toluene has potent behavioral effects, but only recently has progress been made in understanding the neurochemical actions that mediate the action of toluene in the brain. Available evidence suggests that toluene inhalation alters dopamine (DA) neurotransmission, but toluene's mechanism of action is unknown. The present study evaluated the effect of acute and repeated toluene inhalation (0, 2,000, or 4,000 ppm) on locomotor activity as well as striatal DA release and uptake using slice fast-scan cyclic voltammetry. Acutely, 2,000 and 4,000 ppm toluene increased locomotor activity, while neurochemically only 4,000 ppm toluene potentiated electrically evoked DA release across the caudate-putamen and the nucleus accumbens. Repeated administration of toluene resulted in sensitization to toluene's locomotor activity effects. Brain slices obtained from mice repeatedly exposed to toluene demonstrated no difference in stimulated DA release in the caudate-putamen as compared to control animals. Repeated exposure to 2,000 and 4,000 ppm toluene caused a concentration-dependent decrease of 25-50 % in evoked DA release in the nucleus accumbens core and shell relative to air-exposed mice. These voltammetric neurochemical findings following repeated toluene exposure suggest that there may be a compensatory downregulation of the DA system. Acute or repeated toluene exposure had no effect on the DA uptake kinetics. Taken together, these results demonstrate that acute toluene inhalation potentiates DA release, while repeated toluene exposure attenuates DA release in the nucleus accumbens only.

  15. Repeated cue exposure effects on subjective and physiological indices of chocolate craving

    NARCIS (Netherlands)

    van Gucht, D.; Vansteenwegen, D.; Beckers, T.; Hermans, D.; Baeyens, F.; Van den Bergh, O.

    2008-01-01

    The aim of this study is to investigate the effects of repeated unreinforced exposure to chocolate cues in persons reporting chocolate craving. Participants in the experimental group (n ¼ 40) received 10 consecutive brief exposures to chocolate cues in each of two sessions, separated by 1-3 days.

  16. Repeated cue exposure effects on subjective and physiological indices of chocolate craving

    NARCIS (Netherlands)

    van Gucht, D.; Vansteenwegen, D.; Beckers, T.; Hermans, D.; Baeyens, F.; Van den Bergh, O.

    2008-01-01

    The aim of this study is to investigate the effects of repeated unreinforced exposure to chocolate cues in persons reporting chocolate craving. Participants in the experimental group (n ¼ 40) received 10 consecutive brief exposures to chocolate cues in each of two sessions, separated by 1-3 days. Co

  17. Mid-Childhood Bone Mass After Exposure to Repeat Doses of Antenatal Glucocorticoids: A Randomized Trial.

    Science.gov (United States)

    McKinlay, Christopher J D; Cutfield, Wayne S; Battin, Malcolm R; Dalziel, Stuart R; Crowther, Caroline A; Harding, Jane E

    2017-05-01

    Treatment of women at risk for preterm birth with repeat doses of glucocorticoids reduces neonatal morbidity, but could have adverse effects on skeletal development. We assessed whether exposure to repeat antenatal betamethasone alters bone mass in children whose mothers participated in the Australasian Collaborative Trial of Repeat Doses of Corticosteroids. Women were randomized to a single dose of betamethasone or placebo, ≥7 days after an initial course of glucocorticoids, repeated each week that they remained at risk for preterm birth at children underwent whole-body dual-energy radiograph absorptiometry at 6 to 8 years' corrected age. Of 212 eligible childhood survivors, 185 were studied (87%; 91 repeat betamethasone group; 94 placebo [single course] group). Children exposed to repeat antenatal betamethasone and those exposed to placebo had similar whole-body bone mineral content (median repeat betamethasone: 553 g, interquartile range: 442-712 g; placebo: 567 g, interquartile range: 447-750 g; geometric mean ratio: 0.99; 95% confidence interval: 0.94-1.03, P = .55) and bone area (median repeat betamethasone 832 cm(2), interquartile range: 693-963 cm(2); placebo: 822 cm(2), interquartile range: 710-1020 cm(2); geometric mean ratio: 0.99, 95% confidence interval: 0.92-1.07, P = .75). Exposure to repeat doses of antenatal betamethasone compared with a single course of glucocorticoids does not alter bone mass in mid-childhood. Copyright © 2017 by the American Academy of Pediatrics.

  18. The Role of Repeated Exposure to Multimodal Input in Incidental Acquisition of Foreign Language Vocabulary.

    Science.gov (United States)

    Bisson, Marie-Josée; van Heuven, Walter J B; Conklin, Kathy; Tunney, Richard J

    2014-12-01

    Prior research has reported incidental vocabulary acquisition with complete beginners in a foreign language (FL), within 8 exposures to auditory and written FL word forms presented with a picture depicting their meaning. However, important questions remain about whether acquisition occurs with fewer exposures to FL words in a multimodal situation and whether there is a repeated exposure effect. Here we report a study where the number of exposures to FL words in an incidental learning phase varied between 2, 4, 6, and 8 exposures. Following the incidental learning phase, participants completed an explicit learning task where they learned to recognize written translation equivalents of auditory FL word forms, half of which had occurred in the incidental learning phase. The results showed that participants performed better on the words they had previously been exposed to, and that this incidental learning effect occurred from as little as 2 exposures to the multimodal stimuli. In addition, repeated exposure to the stimuli was found to have a larger impact on learning during the first few exposures and decrease thereafter, suggesting that the effects of repeated exposure on vocabulary acquisition are not necessarily constant.

  19. Repeated exposure to noise increases tolerance in a coral reef fish.

    Science.gov (United States)

    Nedelec, Sophie L; Mills, Suzanne C; Lecchini, David; Nedelec, Brendan; Simpson, Stephen D; Radford, Andrew N

    2016-09-01

    Some anthropogenic noise is now considered pollution, with evidence building that noise from human activities such as transportation, construction and exploration can impact behaviour and physiology in a broad range of taxa. However, relatively little research has considered the effects of repeated or chronic noise; extended exposures may result in habituation or sensitisation, and thus changes in response. We conducted a field-based experiment at Moorea Island to investigate how repeated exposure to playback of motorboat noise affected a coral reef fish (Dascyllus trimaculatus). We found that juvenile D. trimaculatus increased hiding behaviour during motorboat noise after two days of repeated exposure, but no longer did so after one and two weeks of exposure. We also found that naïve individuals responded to playback of motorboat noise with elevated ventilation rates, but that this response was diminished after one and two weeks of repeated exposure. We found no strong evidence that baseline blood cortisol levels, growth or body condition were affected by three weeks of repeated motorboat-noise playback. Our study reveals the importance of considering how tolerance levels may change over time, rather than simply extrapolating from results of short-term studies, if we are to make decisions about regulation and mitigation.

  20. Ceftriaxone attenuates locomotor activity induced by acute and repeated cocaine exposure in mice.

    Science.gov (United States)

    Tallarida, Christopher S; Corley, Gladys; Kovalevich, Jane; Yen, William; Langford, Dianne; Rawls, Scott M

    2013-11-27

    Ceftriaxone (CTX) decreases locomotor activation produced by initial cocaine exposure and attenuates development of behavioral sensitization produced by repeated cocaine exposure. An important question that has not yet been answered is whether or not CTX reduces behavioral sensitization to cocaine in cases in which the antibiotic is administered only during the period of cocaine absence that follows repeated cocaine exposure and precedes reintroduction to cocaine. We investigated this question using C57BL/6 mice. Mice pretreated with cocaine (15mg/kg×14 days) and then challenged with cocaine (15mg/kg) after 30 days of cocaine absence displayed sensitization of locomotor activity. For combination experiments, CTX injected during the 30 days of cocaine absence attenuated behavioral sensitization produced by cocaine challenge. In the case in which CTX was injected together with cocaine for 14 days, development of behavioral sensitization to cocaine challenge was also reduced. CTX attenuated the increase in locomotor activity produced by acute cocaine exposure; however, its efficacy was dependent on the dose of cocaine as inhibition was detected against 30mg/kg, but not 15mg/kg, of cocaine. These results from mice indicate that CTX attenuates locomotor activity produced by acute and repeated cocaine exposure and counters cocaine's locomotor activating properties in a paradigm in which the antibiotic is injected during the period of forced cocaine absence that follows repeated cocaine exposure.

  1. Influence of the number of trials and the exercise to rest ratio in repeated sprint ability, with changes of direction and orientation.

    Science.gov (United States)

    Ruscello, Bruno; Tozzo, Nazzareno; Briotti, Gianluca; Padua, Elvira; Ponzetti, Francesco; D'Ottavio, Stefano

    2013-07-01

    The purpose of this investigation was to determine if there were different trends in physical fatigue observed in 3 different sets, of 7 trials each, in repeated sprint training, performed in 3 different modes: straight sprinting over 30 m, shuttle sprinting over 15 + 15 m, and sprinting over 30 m with changes of direction. Recovery time among trials in the sets was administered according to the 1:5 exercise to rest ratio. The sets were performed on 3 different days, with at least 48 hours between each set. The study involved 17 trained male soccer players (height, 177.33 ± 6.21 cm; body mass, 71.63 ± 9.58 kg; body mass index, 23 ± 2.39 kg·m; age, 21.94 ± 3.58 years). To compare the different values of the time recorded, an index of fatigue was used. Significant differences among trials within each set (repeated measures analysis of variance; p repeated sprint ability in nonlinear and multidirectional sprints (shuttle and change of direction), which might imply a different number of trials within the set or different exercise to rest ratios from the ones usually adopted for straight sprinting, to induce similar trends of fatigue. As practical applications, the estimated numbers of necessary trials in the different sets and the possible exercise to rest ratios, resulting from mathematical modeling, are provided for each investigated sprinting mode.

  2. Extension of recovery time from fatigue by repeated rest with short-term sleep during continuous fatigue load: Development of chronic fatigue model.

    Science.gov (United States)

    Kanzaki, Akinori; Okauchi, Takashi; Hu, Di; Shingaki, Tomotaka; Katayama, Yumiko; Koyama, Hidenori; Watanabe, Yasuyoshi; Cui, Yilong

    2016-05-01

    Homeostasis is known to be involved in maintaining the optimal internal environment, helping to achieve the best performance of biological functions. At the same time, a deviation from optimal conditions often attenuates the performance of biological functions, and such restricted performance could be considered as individual fatigue, including physical and mental fatigue. The present study seeks to develop an animal model of chronic or subacute fatigue in which the recovery time is extended through the gradual disruption of homeostasis. We show that repeated short-term rest periods with certain lengths of sleep during continuous fatigue loading extend recovery from spontaneous nighttime activity but not physical performance in comparison with a continuous fatigue-loading procedure. Furthermore, the immobility time in a forced swimming test was extended by repeated short-term rests. These results suggest that repeated short-term rest with certain lengths of sleep during continuous fatigue loading is able to extend the recovery from mental fatigue but not from physical fatigue and that this effect might occur via the disruption of a homeostatic mechanism that is involved in restoring the optimal internal environment.

  3. Repeated Exposure to Sublethal Doses of the Organophosphorus Compound VX Activates BDNF Expression in Mouse Brain

    Science.gov (United States)

    2012-01-01

    cresyl/-4 H-1: 3: 2-benzodioxa- phosphorin-2-oxide (CBDP) on organophosphate poisoning and its therapy. Arch. Toxicol. 42, 207–216. French, S. J... organophosphates or other environmental insults, have a greater FIG. 4. Mice that received repeated exposure to low levels of VX (0.2 LD50 and 0.4 LD50...to neuro- behavioral deficits and neuropathology. Although exposure to organophosphates such as pesticides has been shown to affect the expression of

  4. The levels of kerosene components in biological samples after repeated dermal exposure to kerosene in rats.

    Science.gov (United States)

    Fujihara, Junko; Hieda, Yoko; Tsujino, Yoshio; Xue, Yuying; Takayama, Koji; Kimura, Kojiro; Dekio, Satoshi

    2004-04-01

    The current study was experimentally investigated using rats whether or not kerosene components are accumulated from daily repeated dermal exposure. Rats received daily 1h-exposure to kerosene for 5 days (5K), daily 1h-exposure for 4 days and left for 1 day (4KL), a single 1h-exposure (1K), a single 1h-exposure and left for 1 day (1KL), or a single 1h-exposure, sacrificed and left dead for 1 day (1KLD). Kerosene components, trimethylbenzenes (TMBs) and aliphatic hydrocarbons (AHCs) in blood and tissues were determined by GC-MS. In blood, almost the same concentrations of TMBs were detected in the rats sacrificed immediately after exposure (5K, 1K and 1KLD), and only trace levels were detected in the rats sacrificed 1 day after exposure (4 and 1KL). Almost the same levels of AHCs in blood were detected among groups except for the rats sacrificed 1 day after a single exposure (1KL), in which AHCs were slightly lower. These results suggest that (1) AHCs tend to be accumulated from daily exposure, while TMBs do not, (2) the proportions of detected kerosene components in blood can be an indicator of whether the last exposure occurred just before death or not, (3) the kerosene levels last at least 1 day without blood circulation.

  5. Sweet and sour preferences in young children and adults: role of repeated exposure

    NARCIS (Netherlands)

    Liem, D.G.; Graaf, de C.

    2004-01-01

    The authors investigated the influence of repeated exposure to orangeades with added sucrose and different concentrations of citric acid, on the taste preferences of 6- to-11-year-old children and young adults. During an intervention study of 8 days, 59 children (9.2±0.9 years) and 46 young adults (

  6. Repeated toluene exposure increases c-Fos in catecholaminergic cells of the nucleus accumbens shell.

    Science.gov (United States)

    Tomaszycki, Michelle L; Aulerich, Kelsey E; Bowen, Scott E

    2013-01-01

    Toluene is a frequently abused solvent. Previous studies have suggested that toluene acts like other drugs of abuse, specifically on the dopaminergic system in the nucleus accumbens (NAc) and ventral tegmental area (VTA) of the mesolimbic pathway. Although changes in dopamine (DA) levels and c-Fos have been observed in both acute and repeated exposure paradigms, the extent to which c-Fos is localized to catecholaminergic cells is unknown. The present study tested the effects of repeated toluene exposure (1000-4000ppm) on locomotor activity and cells containing c-Fos, tyrosine hydroxylase (TH), or both in the core and shell of the NAc, as well as the anterior and posterior VTA. We focused our study on adolescents, since adolescence is a time of great neural change and a time when individuals tend to be more susceptible to drug abuse. In early tests, toluene dose-dependently increased locomotor activity. Repeated exposure to the highest concentration of toluene resulted in sensitization to toluene's effects on locomotor activity. Although the number of cells immunopositive for c-Fos or TH did not significantly differ across groups, cells immunopositive for TH+c-Fos were higher in the NAc shell of animals exposed to 4000ppm than in animals exposed to air (control) or 1000ppm. Taken together, these findings demonstrate that repeated high dose toluene exposure increases locomotor activity as well as activation of catecholaminergic cells in the shell of the NAc. © 2013 Elsevier Inc. All rights reserved.

  7. Effect of Repeated Exposures on Word Learning in Quiet and Noise

    Science.gov (United States)

    Blaiser, Kristina M.; Nelson, Peggy B.; Kohnert, Kathryn

    2015-01-01

    This study examines the impact of repeated exposures on word learning of preschool children with and without hearing loss (HL) in quiet and noise conditions. Participants were 19 children with HL and 17 peers with normal hearing (NH). Children were introduced to 16 words: 8 in quiet and 8 in noise conditions. Production and identification scores…

  8. Sweet and sour preferences in young children and adults: role of repeated exposure

    NARCIS (Netherlands)

    Liem, D.G.; Graaf, de C.

    2004-01-01

    The authors investigated the influence of repeated exposure to orangeades with added sucrose and different concentrations of citric acid, on the taste preferences of 6- to-11-year-old children and young adults. During an intervention study of 8 days, 59 children (9.2±0.9 years) and 46 young adults

  9. Effect of repeated exposures and sociality on novel food acceptance and consumption by orangutans.

    Science.gov (United States)

    Hardus, Madeleine E; Lameira, Adriano R; Wich, Serge A; de Vries, Han; Wahyudi, Rachmad; Shumaker, Robert W; Menken, Steph B J

    2015-01-01

    Hundreds of rehabilitant great apes have been released into the wild, and thousands await release. However, survival rates after release can be as low as 20%. Several factors influence individuals' survival rates, one of which is the capacity to obtain an adequate diet once released. Released individuals are faced with a mixture of familiar and novel foods in an unfamiliar forest; therefore, it is important to understand how they increase acceptance and consumption of novel foods. This is especially vital for omnivorous species, such as wild great apes, which consume several hundred species of different foods. We assessed the effects of repeated exposures and sociality (i.e. co-feeding in the presence of one or more other individuals) on the acceptance and consumption of novel foods by captive orangutans (Pongo sp). Repeated exposures of food (novel, at first) did not cause an increase of acceptance of food; in other words, the orangutans did not start to eat a food item after being exposed to that food more often, but repeated exposures of food increased consumption (i.e. quantity). After repeated exposures, the orangutans also became gradually more familiar with the food, decreasing their explorative behaviour. The presence of co-feeding conspecifics resulted in an increased acceptance of the novel food by orangutans, and they ate a larger amount of said foods than when alone. Repeated exposure and sociality may benefit rehabilitant great apes in augmenting and diversifying diet and, once practiced before release, may accelerate an individuals' adaptation to their new habitat, improving survival chances. Great ape rescue, rehabilitation and reintroduction require large financial and logistic investments; however, their effectiveness may be improved at low cost and low effort through the suggested measures.

  10. Can the Palatability of Healthy, Satiety-Promoting Foods Increase with Repeated Exposure during Weight Loss?

    Science.gov (United States)

    Anguah, Katherene O.-B.; Lovejoy, Jennifer C.; Craig, Bruce A.; Gehrke, Malinda M.; Palmer, Philip A.; Eichelsdoerfer, Petra E.; McCrory, Megan A.

    2017-01-01

    Repeated exposure to sugary, fatty, and salty foods often enhances their appeal. However, it is unknown if exposure influences learned palatability of foods typically promoted as part of a healthy diet. We tested whether the palatability of pulse containing foods provided during a weight loss intervention which were particularly high in fiber and low in energy density would increase with repeated exposure. At weeks 0, 3, and 6, participants (n = 42; body mass index (BMI) 31.2 ± 4.3 kg/m2) were given a test battery of 28 foods, approximately half which had been provided as part of the intervention, while the remaining half were not foods provided as part of the intervention. In addition, about half of each of the foods (provided as part or not provided as part of the intervention) contained pulses. Participants rated the taste, appearance, odor, and texture pleasantness of each food, and an overall flavor pleasantness score was calculated as the mean of these four scores. Linear mixed model analyses showed an exposure type by week interaction effect for taste, texture and overall flavor pleasantness indicating statistically significant increases in ratings of provided foods in taste and texture from weeks 0 to 3 and 0 to 6, and overall flavor from weeks 0 to 6. Repeated exposure to these foods, whether they contained pulses or not, resulted in a ~4% increase in pleasantness ratings. The long-term clinical relevance of this small increase requires further study. PMID:28231094

  11. Effects of repeatability measures on results of fMRI sICA: a study on simulated and real resting-state effects.

    Science.gov (United States)

    Remes, Jukka J; Starck, Tuomo; Nikkinen, Juha; Ollila, Esa; Beckmann, Christian F; Tervonen, Osmo; Kiviniemi, Vesa; Silven, Olli

    2011-05-15

    Spatial independent components analysis (sICA) has become a widely applied data-driven method for fMRI data, especially for resting-state studies. These sICA approaches are often based on iterative estimation algorithms and there are concerns about accuracy due to noise. Repeatability measures such as ICASSO, RAICAR and ARABICA have been introduced as remedies but information on their effects on estimates is limited. The contribution of this study was to provide more of such information and test if the repeatability analyses are necessary. We compared FastICA-based ordinary and repeatability approaches concerning mixing vector estimates. Comparisons included original FastICA, FSL4 Melodic FastICA and original and modified ICASSO. The effects of bootstrapping and convergence threshold were evaluated. The results show that there is only moderate improvement due to repeatability measures and only in the bootstrapping case. Bootstrapping attenuated power from time courses of resting-state network related ICs at frequencies higher than 0.1 Hz and made subsets of low frequency oscillations more emphasized IC-wise. The convergence threshold did not have a significant role concerning the accuracy of estimates. The performance results suggest that repeatability measures or strict converge criteria might not be needed in sICA analyses of fMRI data. Consequently, the results in existing sICA fMRI literature are probably valid in this sense. A decreased accuracy of original bootstrapping ICASSO was observed and corrected by using centrotype mixing estimates but the results warrant for thorough evaluations of data-driven methods in general. Also, given the fMRI-specific considerations, further development of sICA methods is strongly encouraged. Copyright © 2010 Elsevier Inc. All rights reserved.

  12. Repeated Ketamine Exposure Induces an Enduring Resilient Phenotype in Adolescent and Adult Rats

    Science.gov (United States)

    Parise, Eric M.; Alcantara, Lyonna F.; Warren, Brandon L.; Wright, Katherine N.; Hadad, Roey; Sial, Omar K.; Kroeck, Kyle G.; Iñiguez, Sergio D.; Bolaños-Guzmán, Carlos A.

    2013-01-01

    Background Major Depressive Disorder (MDD) afflicts up to 10% of adolescents. However, nearly 50% of those afflicted are considered non-responsive to available treatments. Ketamine, a non-competitive N-methyl-D-aspartate (NMDA) receptor antagonist has shown potential as a rapid-acting and long-lasting treatment for MDD in adults. Thus, the effectiveness and functional consequences of ketamine exposure during adolescence were explored. Methods Adolescent male rats (postnatal day [PD] 35) received two ketamine (0, 5, 10 or 20 mg/kg) injections, 4 hours apart, after exposure to day 1 of the forced swim test (FST). The next day, rats were re-exposed to the FST to assess ketamine-induced antidepressant-like responses. Separate groups were exposed to chronic unpredictable stress (CUS) to confirm findings from the FST. After these initial experiments, adolescent naïve rats were exposed to either 1 or 15 consecutive days (PD35–49) of ketamine (20 mg/kg) twice/daily. Ketamine's influence on behavioral reactivity to rewarding (i.e., sucrose preference) and aversive (i.e., elevated plus-maze, FST) circumstances was then assessed 2 months after treatment. To control for age-dependent effects, adult rats (PD75–89) were exposed to identical experimental conditions. Results Ketamine (20 mg/kg) reversed the CUS-induced depression-like behaviors in the FST. Repeated ketamine exposure resulted in anxiolytic- and antidepressant-like responses 2 months after drug exposure. None of the ketamine doses used were capable of inducing drug-seeking behaviors as measured by place preference conditioning. Conclusions Repeated ketamine exposure induces enduring resilient-like responses regardless of age of exposure. These findings point to ketamine, and its repeated exposure, as a potentially useful antidepressant during adolescence. PMID:23790225

  13. The effects of repeated exposure to graphic fear appeals on cigarette packages: A field experiment.

    Science.gov (United States)

    Dijkstra, Arie; Bos, Colin

    2015-03-01

    Experimental studies on the effects of graphic fear appeals on cigarette packages typically expose smokers in a single session to a fear appeal, although in practice the exposure is always repeated. The present study applied an improved study design with repeated exposure to fear appeals on cigarette packages. In this field-experiment, 118 smokers were assigned to 1 of 2 conditions with either graphic fear appeals or textual warnings on their cigarette packages. During 3 weeks, fear and disgust were assessed 6 times. The intention to quit smoking after 3 weeks and quitting activity during the 3 weeks were the dependent measures. The effects of 3 pretest individual difference moderators were tested: disengagement beliefs, number of cigarettes smoked a day, and readiness to quit. Three weeks of exposure to the graphic fear appeals led to a stronger intention to quit, but only when smokers scored low on disengagement beliefs, or were heavier smokers. In addition, smokers low in disengagement more often reported to have cut down on smoking in the graphic condition. There were no indications of habituation of fear and disgust over the 3 weeks. The effects of graphic fear appeals depended on smokers' characteristics: The moderators may explain the mixed findings in the literature. The lack of habituation may be caused by the renewal of the graphics every few days. The used field-experimental design with natural repeated exposure to graphics is promising.

  14. Acquired (dis)liking of natural cheese in different repeated exposure environment.

    Science.gov (United States)

    Go, Jung-Eun; Kim, Mi-Ran; Chung, Seo-Jin

    2017-09-01

    This study investigated the development of (dis)liking of various types of natural cheese with repeated exposures among Korean young females in two environment settings. Six types of natural cheese with varying flavor and texture characteristics were selected: Brie, Emmental, Gorgonzola, Gouda, Parmigiano-Reggiano and sharp Cheddar. The subjects were randomly divided into two groups (individual evaluation vs. social interaction) and exposed to all six types of cheeses eight times for 4 weeks. The acceptance scores for these cheeses were monitored at the beginning (first taste test) and end (second taste test) of the exposure test as well as 1 month after the completion of exposure test (third taste test). The results showed that the acceptance of cheese was affected by the cheese type and the number of test trials but not by tasting environment. The acceptance levels were higher for Brie, Gouda and sharp Cheddar than for Emmental, Gorgonzola and Parmigiano-Reggiano. When the subjects were exposed to Brie, Emmental, Gouda, and sharp Cheddar repeatedly, their acceptance level increased significantly. This study demonstrated that the liking of natural cheese can occur through repeated exposure to the cheese, but with the outcome varying with the type of cheese. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. [Estimation of heritability and repeatability of resting metabolic rate in birds, with free-living pied flycatchers Ficedula hypoleuca (Aves: Passeriformes) as an example].

    Science.gov (United States)

    Bushuev, A V; Kerimov, A B; Ivankina, E V

    2010-01-01

    Estimates of a trait heritability and repeatability can get at an idea of its usefulness for being an individual characteristic and its ability to change under selection pressure. Heritability and repeatability of energetic parameters still poorly studied in birds. The most important physiological characteristic of homoiotherms is resting metabolic rate (RMR), which, in the absence of productive processes, does not exceed basal metabolic rate (BMR). We estimated BMR repeatability in free-living pied flycatchers in Moscow Region (55 degrees 44' N, 36 degrees 51' E; 1992-2008) and Tomsk (56 degrees 20' N, 84 degrees 56' E; 2008-2009) populations over intervals from 40 days to 3 years. In Moscow Region population, BMR repeatability amounted to tau = 0.34 +/- 0.10 (n=80) if measured over 1 year interval, tau = 0.60 +/- 0.15 (n=19) if measured over 2 years interval, and tau = 0.85 +/- 0.13 (n=6) if measured over 3 years interval providing that consecutive BMR measurements were done in the same period of reproductive season. In Tomsk population, BMR repeatability, measured over 1 year interval, amounted to tau = 0.49 +/- 0.11 (n=50). Repeatability is a measure of a trait constancy and sets the upper limit of its heritability. To estimate RMR heritability, cross-fostering experiments have been conducted in 2003-2005 with flycatchers of Moscow Region population. RMR of chicks positively correlated with BMR of their biological fathers, whereas such correlation in metabolic rates between chicks and their foster fathers was absent. The RMR heritability estimate turned out to be h2 = 0.43 +/- 0.17 (n=210). The obtained estimates of heritability and repeatability of fundamental energetic traits are rather high for physiological features. This suggests the existence of a potential for direct selection on BMR and evolutionary stable diversity of avian populations with regard to basal metabolic rate.

  16. A model of human nasal epithelial cells adapted for direct and repeated exposure to airborne pollutants.

    Science.gov (United States)

    Bardet, Gaëlle; Achard, Sophie; Loret, Thomas; Desauziers, Valérie; Momas, Isabelle; Seta, Nathalie

    2014-08-17

    Airway epithelium lining the nasal cavity plays a pivotal role in respiratory tract defense and protection mechanisms. Air pollution induces alterations linked to airway diseases such as asthma. Only very few in vitro studies to date have succeeded in reproducing physiological conditions relevant to cellular type and chronic atmospheric pollution exposure. We therefore, set up an in vitro model of human Airway Epithelial Cells of Nasal origin (hAECN) close to real human cell functionality, specifically adapted to study the biological effects of exposure to indoor gaseous pollution at the environmental level. hAECN were exposed under air-liquid interface, one, two, or three-times at 24 h intervals for 1 h, to air or formaldehyde (200 μg/m(3)), an indoor air gaseous pollutant. All experiments were ended at day 4, when both cellular viability and cytokine production were assessed. Optimal adherence and confluence of cells were obtained 96 h after cell seeding onto collagen IV-precoated insert. Direct and repeated exposure to formaldehyde did not produce any cellular damage or IL-6 production change, although weak lower IL-8 production was observed only after the third exposure. Our model is significantly better than previous ones due to cell type and the repeated exposure protocol.

  17. Repeated exposure to sublethal doses of the organophosphorus compound VX activates BDNF expression in mouse brain.

    Science.gov (United States)

    Pizarro, Jose M; Chang, Wenling E; Bah, Mariama J; Wright, Linnzi K M; Saviolakis, George A; Alagappan, Arun; Robison, Christopher L; Shah, Jinesh D; Meyerhoff, James L; Cerasoli, Douglas M; Midboe, Eric G; Lumley, Lucille A

    2012-04-01

    The highly toxic organophosphorus compound VX [O-ethyl S-[2-(diisopropylamino)ethyl]methylphosphonate] is an irreversible inhibitor of the enzyme acetylcholinesterase (AChE). Prolonged inhibition of AChE increases endogenous levels of acetylcholine and is toxic at nerve synapses and neuromuscular junctions. We hypothesized that repeated exposure to sublethal doses of VX would affect genes associated with cell survival, neuronal plasticity, and neuronal remodeling, including brain-derived neurotrophic factor (BDNF). We examined the time course of BDNF expression in C57BL/6 mouse brain following repeated exposure (1/day × 5 days/week × 2 weeks) to sublethal doses of VX (0.2 LD(50) and 0.4 LD(50)). BDNF messenger RNA expression was significantly (p VX exposure. BDNF protein expression, however, was only increased in the CA3 region of the hippocampus. Whether increased BDNF in response to sublethal doses of VX exposure is an adaptive response to prevent cellular damage or a precursor to impending brain damage remains to be determined. If elevated BDNF is an adaptive response, exogenous BDNF may be a potential therapeutic target to reduce the toxic effects of nerve agent exposure.

  18. HEARING LOSS IN THE RHESUS MONKEY AFTER REPEATED EXPOSURES TO IDENTICAL NOISES,

    Science.gov (United States)

    hearing loss in monkeys. Five animals were exposed to repeated single-pulse noises alternately at 72- and 96-hour intervals, to observe intersubject and intra-subject variations in hearing behavior under similar physical-noise conditions. Audiograms were taken periodically, from two minutes after exposure to 72 hours later, for 2 and 4 kc test tones. There were distinctive differences in individual-animal patterns of hearing loss and recovery. Two animals clearly showed smaller hearing losses during the later exposure sessions, and that loss

  19. Enhanced resistance to UV-B radiation in Anabaena sp. PCC 7120 (Cyanophyceae) by repeated exposure.

    Science.gov (United States)

    Qin, Hongjie; Li, Dunhai

    2014-07-01

    In natural habitats, organisms especially phytoplankton are not always continuously subjected to ultraviolet-B radiation (UVBR). By simulation of the natural situation, the N2-fixing cyanobacterium Anabaena sp. PCC 7120 was subjected to UV-B exposure and recovery cycles. A series of morphological and physiological changes were observed in Anabaena sp. PCC 7120 under repeated UVBR when compared with controls. Such as the breakage of filaments, intervals between heterocysts, heterocyst frequency, total carbohydrate, and carotenoids were increased, while the nitrogenase activity and photosynthetic activity were inhibited by repeated UVBR; however, these activities could recover when UV-B stress was removed. Unexpectedly, the over-compensatory growth was observed at the end of the second round of exposure and recovery cycle. Our results showed that discontinuous UVBR could increase the growth rate and the tolerance as well as repair capacity of Anabaena sp. PCC 7120. These results indicate that moderate UVBR may increase the growth of cyanobacteria in natural habitats.

  20. Eye lens radiation exposure and repeated head CT scans: A problem to keep in mind

    Energy Technology Data Exchange (ETDEWEB)

    Michel, Morgane; Jacob, Sophie [Institute for Radiological Protection and Nuclear Safety, IRSN/DRPH/SRBE/Laboratoire d' Epidemiologie, BP 17, 92 262 Fontenay-aux-Roses (France); Roger, Gilles [Otolaryngology Department, Trousseau Hospital, Paris (France); Pelosse, Beatrice [Ophthalmology Department, Trousseau Hospital, Paris (France); Laurier, Dominique [Institute for Radiological Protection and Nuclear Safety, IRSN/DRPH/SRBE/Laboratoire d' Epidemiologie, BP 17, 92 262 Fontenay-aux-Roses (France); Le Pointe, Hubert Ducou [Radiology Department, Trousseau Hospital, Paris (France); Bernier, Marie-Odile, E-mail: marie-odile.bernier@irsn.fr [Institute for Radiological Protection and Nuclear Safety, IRSN/DRPH/SRBE/Laboratoire d' Epidemiologie, BP 17, 92 262 Fontenay-aux-Roses (France)

    2012-08-15

    Objectives: The deterministic character of radiation-induced cataract is being called into question, raising the possibility of a risk in patients, especially children, exposed to ionizing radiation in case of repeated head CT-scans. This study aims to estimate the eye lens doses of a pediatric population exposed to repeated head CTs and to assess the feasibility of an epidemiological study. Methods: Children treated for a cholesteatoma, who had had at least one CT-scan of the middle ear before their tenth birthday, were included. Radiation exposure has been assessed from medical records and telephone interviews. Results: Out of the 39 subjects contacted, 32 accepted to participate. A total of 76 CT-scans were retrieved from medical records. At the time of the interview (mean age: 16 years), the mean number of CT per child was 3. Cumulative mean effective and eye lens doses were 1.7 mSv and 168 mGy, respectively. Conclusion: A relatively high lens radiation dose was observed in children exposed to repeated CT-scans. Due to that exposure and despite the difficulties met when trying to reach patients' families, a large scale epidemiological study should be performed in order to assess the risk of radiation-induced cataracts associated with repeated head CT.

  1. Early-life stress exposure associated with altered prefrontal resting-state fMRI connectivity in young children

    Directory of Open Access Journals (Sweden)

    Özlem Ece Demir-Lira

    2016-06-01

    Full Text Available Early-life stress (ELS exposure is associated with adverse outcomes across the lifespan. We examined the relation of ELS exposure to resting-state fMRI in children ages 4–7 years. ELS in the first years of life, but not concurrent, was associated with higher regional homogeneity of resting-state fMRI in the left lateral frontal cortex. Resting-state fMRI functional connectivity analyses showed that the region of left lateral frontal cortex demonstrating heightened regional homogeneity associated with ELS was negatively correlated with right temporal/parahippocampal areas. Moreover, higher regional homogeneity in the left lateral frontal cortex and its negative coupling with the right middle temporal/parahippocampal areas were associated with poorer performance on a reversal-learning task performed outside the scanner. Association of ELS exposure with regional homogeneity was independent of other early adversities. These findings suggest that ELS may influence the development of cognitive control in the lateral prefrontal cortex and its interactions with temporal cortex.

  2. Enhancing consumer liking of low salt tomato soup over repeated exposure by herb and spice seasonings.

    Science.gov (United States)

    Ghawi, Sameer Khalil; Rowland, Ian; Methven, Lisa

    2014-10-01

    There is strong evidence for the link between high dietary sodium and increased risk of cardiovascular disease which drives the need to reduce salt content in foods. In this study, herb and spice blends were used to enhance consumer acceptability of a low salt tomato soup (0.26% w/w). Subjects (n = 148) scored their liking of tomato soup samples over 5 consecutive days. The first and last days were pre-and post-exposure visits where all participants rated three tomato soup samples; standard, low salt and low salt with added herbs and spices. The middle 3 days were the repeated exposure phase where participants were divided into three balanced groups; consuming the standard soup, the low salt soup, or the low salt soup with added herbs and spices. Reducing salt in the tomato soup led to a significant decline in consumer acceptability, and incorporating herbs and spices did not lead to an immediate enhancement in liking. However, inclusion of herbs and spices enhanced the perception of the salty taste of the low salt soup to the same level as the standard. Repeated exposure to the herbs and spice-modified soup led to a significant increase in the overall liking and liking of flavour, texture and aftertaste of the soup, whereas no changes in liking were observed for the standard and low salt tomato soups over repeated exposure. Moreover, a positive trend in increasing the post-exposure liking of the herbs and spices soup was observed. The findings suggest that the use of herbs and spices is a useful approach to reduce salt content in foods; however, herbs and spices should be chosen carefully to complement the food as large contrasts in flavour can polarise consumer liking. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  3. Seroepidemiological studies indicate frequent and repeated exposure to Campylobacter spp. during childhood.

    Science.gov (United States)

    Ang, C W; Teunis, P F M; Herbrink, P; Keijser, J; Van Duynhoven, Y H T P; Visser, C E; Van Pelt, W

    2011-09-01

    The annual number of episodes of clinical gastroenteritis caused by Campylobacter spp. in The Netherlands is estimated to be 75 000, i.e. once per 200 person life-years. This number is based on extrapolation of culture results from population-based studies. The number of culture-confirmed cases of Campylobacter infection peaks in the first 3 years of life and again between the ages of 20 and 25 years. The seroepidemiology of Campylobacter describes the relationship between age and exposure to Campylobacter and reflects both symptomatic and asymptomatic infections. Using a validated ELISA system, antibodies to Campylobacter were measured in an age-stratified sample (n=456) of the PIENTER serum collection of the Dutch general population. The seroprevalence of Campylobacter IgG antibodies increased with age, reaching almost 100% at age 20 years. Antibody levels steadily increased with age until young adulthood, suggesting repeated exposure to Campylobacter. In conclusion, seroepidemiological data demonstrated repeated exposures to Campylobacter throughout life, most of which do not lead to clinical symptoms. From young adulthood, >95% of the population in The Netherlands had serological evidence for exposure to Campylobacter.

  4. 5-Day repeated inhalation and 28-day post-exposure study of graphene.

    Science.gov (United States)

    Shin, Jae Hoon; Han, Sung Gu; Kim, Jin Kwon; Kim, Boo Wook; Hwang, Joo Hwan; Lee, Jong Seong; Lee, Ji Hyun; Baek, Jin Ee; Kim, Tae Gyu; Kim, Keun Soo; Lee, Heon Sang; Song, Nam Woong; Ahn, Kangho; Yu, Il Je

    2015-01-01

    Graphene has recently been attracting increasing attention due to its unique electronic and chemical properties and many potential applications in such fields as semiconductors, energy storage, flexible electronics, biosensors and medical imaging. However, the toxicity of graphene in the case of human exposure has not yet been clarified. Thus, a 5-day repeated inhalation toxicity study of graphene was conducted using a nose-only inhalation system for male Sprague-Dawley rats. A total of three groups (20 rats per group) were compared: (1) control (ambient air), (2) low concentration (0.68 ± 0.14 mg/m(3) graphene) and (3) high concentration (3.86 ± 0.94 mg/m(3) graphene). The rats were exposed to graphene for 6 h/day for 5 days, followed by recovery for 1, 3, 7 or 28 days. The bioaccumulation and macrophage ingestion of the graphene were evaluated in the rat lungs. The exposure to graphene did not change the body weights or organ weights of the rats after the 5-day exposure and during the recovery period. No statistically significant difference was observed in the levels of lactate dehydrogenase, protein and albumin between the exposed and control groups. However, graphene ingestion by alveolar macrophages was observed in the exposed groups. Therefore, these results suggest that the 5-day repeated exposure to graphene only had a minimal toxic effect at the concentrations and time points used in this study.

  5. Effect of repeated benzene inhalation exposures on benzene metabolism, binding to hemoglobin, and induction of micronuclei.

    Science.gov (United States)

    Sabourin, P J; Sun, J D; MacGregor, J T; Wehr, C M; Birnbaum, L S; Lucier, G; Henderson, R F

    1990-05-01

    Metabolism of benzene is thought to be necessary to produce the toxic effects, including carcinogenicity, associated with benzene exposure. To extrapolate from the results of rodent studies to potential health risks in man, one must know how benzene metabolism is affected by species, dose, dose rate, and repeated versus single exposures. The purpose of our studies was to determine the effect of repeated inhalation exposures on the metabolism of [14C]benzene by rodents. Benzene metabolism was assessed by characterizing and quantitating urinary metabolites, and by quantitating 14C bound to hemoglobin and micronuclei induction. F344/N rats and B6C3F1 mice were exposed, nose-only, to 600 ppm benzene or to air (control) for 6 hr/day, 5 days/week for 3 weeks. On the last day, both benzene-pretreated and control animals were exposed to 600 ppm, 14C-labeled benzene for 6 hr. Individual benzene metabolites in urine collected for 24 hr after the exposure were analyzed. There was a significant decrease in the respiratory rate of mice (but not rats) pretreated with benzene which resulted in lower levels of urinary [14C]benzene metabolites. The analyses indicated that the only effects of benzene pretreatment on the metabolite profile in rat or mouse urine were a slight shift from glucuronidation to sulfation in mice and a shift from sulfation to glucuronidation in rats. Benzene pretreatment also had no effect, in either species, on formation of [14C]benzene-derived hemoglobin adducts. Mice and rats had similar levels of hemoglobin adduct binding, despite the higher metabolism of benzene by mice. This indicates that hemoglobin adduct formation occurs with higher efficiency in rats. After 1 week of exposure to 600 ppm benzene, the frequency of micronucleated, polychromatic erythrocytes (PCEs) in mice was significantly increased. Exposure to the same level of benzene for an additional 2 weeks did not further increase the frequency of micronuclei in PCEs. These results indicate

  6. Repeated low-dose exposures to sarin, soman, or VX affect acoustic startle in guinea pigs.

    Science.gov (United States)

    Smith, C D; Lee, R B; Moran, A V; Sipos, M L

    2016-01-01

    Chemical warfare nerve agents (CWNAs) are known to cause behavioral abnormalities in cases of human exposures and in animal models. The behavioral consequences of single exposures to CWNAs that cause observable toxic signs are particularly well characterized in animals; however, less is known regarding repeated smaller exposures that may or may not cause observable toxic signs. In the current study, guinea pigs were exposed to fractions (0.1, 0.2, or 0.4) of a medial lethal dose (LD50) of sarin, soman, or VX for two weeks. On each exposure day, and for a post-exposure period, acoustic startle response (ASR) was measured in each animal. Although relatively few studies use guinea pigs to measure behavior, this species is ideal for CWNA-related experiments because their levels of carboxylesterases closely mimic those of humans, unlike rats or mice. Results showed that the 0.4 LD50 doses of soman and VX transiently increased peak startle amplitude by the second week of injections, with amplitude returning to baseline by the second week post-exposure. Sarin also increased peak startle amplitude independent of week. Latencies to peak startle and PPI were affected by agent exposure but not consistently among the three agents. Most of the changes in startle responses returned to baseline following the cessation of exposures. These data suggest that doses of CWNAs not known to produce observable toxic signs in guinea pigs can affect behavior in the ASR paradigm. Further, these deficits are transient and usually return to baseline shortly after the end of a two-week exposure period.

  7. Consequences of repeated ethanol exposure during early or late adolescence on conditioned taste aversions in rats

    Directory of Open Access Journals (Sweden)

    Jessica Saalfield

    2015-12-01

    Full Text Available Alcohol use is prevalent during adolescence, yet little is known about possible long-lasting consequences. Recent evidence suggests that adolescents are less sensitive than adults to ethanol's aversive effects, an insensitivity that may be retained into adulthood after repeated adolescent ethanol exposure. This study assessed whether intermittent ethanol exposure during early or late adolescence (early-AIE or late-AIE, respectively would affect ethanol conditioned taste aversions 2 days (CTA1 and >3 weeks (CTA2 post-exposure using supersaccharin and saline as conditioning stimuli (CS, respectively. Pair-housed male Sprague-Dawley rats received 4 g/kg i.g. ethanol (25% or water every 48 h from postnatal day (P 25–45 (early AIE or P45-65 (late AIE, or were left non-manipulated (NM. During conditioning, 30 min home cage access to the CS was followed by 0, 1, 1.5, 2 or 2.5 g/kg ethanol i.p., with testing 2 days later. Attenuated CTA relative to controls was seen among early and late AIE animals at both CTA1 and CTA2, an effect particularly pronounced at CTA1 after late AIE. Thus, adolescent exposure to ethanol was found to induce an insensitivity to ethanol CTA seen soon after exposure and lasting into adulthood, and evident with ethanol exposures not only early but also later in adolescence.

  8. Consequences of repeated ethanol exposure during early or late adolescence on conditioned taste aversions in rats.

    Science.gov (United States)

    Saalfield, Jessica; Spear, Linda

    2015-12-01

    Alcohol use is prevalent during adolescence, yet little is known about possible long-lasting consequences. Recent evidence suggests that adolescents are less sensitive than adults to ethanol's aversive effects, an insensitivity that may be retained into adulthood after repeated adolescent ethanol exposure. This study assessed whether intermittent ethanol exposure during early or late adolescence (early-AIE or late-AIE, respectively) would affect ethanol conditioned taste aversions 2 days (CTA1) and >3 weeks (CTA2) post-exposure using supersaccharin and saline as conditioning stimuli (CS), respectively. Pair-housed male Sprague-Dawley rats received 4g/kg i.g. ethanol (25%) or water every 48 h from postnatal day (P) 25-45 (early AIE) or P45-65 (late AIE), or were left non-manipulated (NM). During conditioning, 30 min home cage access to the CS was followed by 0, 1, 1.5, 2 or 2.5g/kg ethanol i.p., with testing 2 days later. Attenuated CTA relative to controls was seen among early and late AIE animals at both CTA1 and CTA2, an effect particularly pronounced at CTA1 after late AIE. Thus, adolescent exposure to ethanol was found to induce an insensitivity to ethanol CTA seen soon after exposure and lasting into adulthood, and evident with ethanol exposures not only early but also later in adolescence.

  9. Dealing with consumer differences in liking during repeated exposure to food; typical dynamics in rating behavior.

    Science.gov (United States)

    Dalenberg, Jelle R; Nanetti, Luca; Renken, Remco J; de Wijk, René A; Ter Horst, Gert J

    2014-01-01

    Consumers show high interindividual variability in food liking during repeated exposure. To investigate consumer liking during repeated exposure, data is often interpreted on a product level by averaging results over all consumers. However, a single product may elicit inconsistent behaviors in consumers; averaging will mix and hide possible subgroups of consumer behaviors, leading to a misinterpretation of the results. To deal with the variability in consumer liking, we propose to use clustering on data from consumer-product combinations to investigate the nature of the behavioral differences within the complete dataset. The resulting behavioral clusters can then be used to describe product acceptance. To test this approach we used two independent data sets in which young adults were repeatedly exposed to drinks and snacks, respectively. We found that five typical consumer behaviors existed in both datasets. These behaviors differed both in the average level of liking as well as its temporal dynamics. By investigating the distribution of a single product across typical consumer behaviors, we provide more precise insight in how consumers divide in subgroups based on their product liking (i.e. product modality). This work shows that taking into account and using interindividual differences can unveil information about product acceptance that would otherwise be ignored.

  10. Individual Variability and Test-Retest Reliability Revealed by Ten Repeated Resting-State Brain Scans over One Month.

    Directory of Open Access Journals (Sweden)

    Bing Chen

    Full Text Available Individual differences in mind and behavior are believed to reflect the functional variability of the human brain. Due to the lack of a large-scale longitudinal dataset, the full landscape of variability within and between individual functional connectomes is largely unknown. We collected 300 resting-state functional magnetic resonance imaging (rfMRI datasets from 30 healthy participants who were scanned every three days for one month. With these data, both intra- and inter-individual variability of six common rfMRI metrics, as well as their test-retest reliability, were estimated across multiple spatial scales. Global metrics were more dynamic than local regional metrics. Cognitive components involving working memory, inhibition, attention, language and related neural networks exhibited high intra-individual variability. In contrast, inter-individual variability demonstrated a more complex picture across the multiple scales of metrics. Limbic, default, frontoparietal and visual networks and their related cognitive components were more differentiable than somatomotor and attention networks across the participants. Analyzing both intra- and inter-individual variability revealed a set of high-resolution maps on test-retest reliability of the multi-scale connectomic metrics. These findings represent the first collection of individual differences in multi-scale and multi-metric characterization of the human functional connectomes in-vivo, serving as normal references for the field to guide the use of common functional metrics in rfMRI-based applications.

  11. Increased resting-state perfusion after repeated encoding is related to later retrieval of declarative associative memories.

    Directory of Open Access Journals (Sweden)

    Georg Groen

    Full Text Available Electrophysiological studies in animals have shown coordinated reactivation of neuronal ensembles during a restricted time period of behavioral inactivity that immediately followed active encoding. In the present study we directly investigated off-line processing of associative memory formation in the human brain. Subjects' regional cerebral blood flow (rCBF as a surrogate marker of neural activity during rest was measured by MR-based perfusion imaging in a sample of 14 healthy male subjects prior to (Pre2 and after (Post extensive learning of 24 face-name associations within a selective reminding task (SR. Results demonstrated significant Post-Pre2 rCBF increases in hippocampal and temporal lobe regions, while in a control comparison of two perfusion scans with no learning task in-between (Pre2-Pre1 no differences in rCBF emerged. Post perfusion scanning was followed by a surprise cued associative recall task from which two types of correctly retrieved names were obtained: older names already correctly retrieved at least once during one of the SR blocks, and recent names acquired during the last SR block immediately prior to the Post scan. In the anterior hippocampus individual perfusion increases were correlated with both correct retrievals of older and recent names. By contrast, older but not recently learned names showed a significant correlation with perfusion increases in the left lateral temporal cortex known to be associated with long-term memory. Recent, but not older names were correlated with dopaminergic midbrain structures reported to contribute to the persistence of memory traces for novel information. Although the direct investigation of off-line memory processing did not permit concomitant experimental control, neither intentional rehearsal, nor substantial variations in subjects' states of alertness appear to contribute to present results. We suggest that the observed rCBF increases might reflect processes that possibly

  12. Increased resting-state perfusion after repeated encoding is related to later retrieval of declarative associative memories.

    Science.gov (United States)

    Groen, Georg; Sokolov, Alexander N; Jonas, Christina; Roebling, Robert; Spitzer, Manfred

    2011-05-12

    Electrophysiological studies in animals have shown coordinated reactivation of neuronal ensembles during a restricted time period of behavioral inactivity that immediately followed active encoding. In the present study we directly investigated off-line processing of associative memory formation in the human brain. Subjects' regional cerebral blood flow (rCBF) as a surrogate marker of neural activity during rest was measured by MR-based perfusion imaging in a sample of 14 healthy male subjects prior to (Pre2) and after (Post) extensive learning of 24 face-name associations within a selective reminding task (SR). Results demonstrated significant Post-Pre2 rCBF increases in hippocampal and temporal lobe regions, while in a control comparison of two perfusion scans with no learning task in-between (Pre2-Pre1) no differences in rCBF emerged. Post perfusion scanning was followed by a surprise cued associative recall task from which two types of correctly retrieved names were obtained: older names already correctly retrieved at least once during one of the SR blocks, and recent names acquired during the last SR block immediately prior to the Post scan. In the anterior hippocampus individual perfusion increases were correlated with both correct retrievals of older and recent names. By contrast, older but not recently learned names showed a significant correlation with perfusion increases in the left lateral temporal cortex known to be associated with long-term memory. Recent, but not older names were correlated with dopaminergic midbrain structures reported to contribute to the persistence of memory traces for novel information. Although the direct investigation of off-line memory processing did not permit concomitant experimental control, neither intentional rehearsal, nor substantial variations in subjects' states of alertness appear to contribute to present results. We suggest that the observed rCBF increases might reflect processes that possibly contribute to the long

  13. The effects of chronic cadmium exposure on repeat swimming performance and anaerobic metabolism in brown trout (Salmo trutta) and lake whitefish (Coregonus clupeaformis)

    Energy Technology Data Exchange (ETDEWEB)

    Cunningham, Jessie L.; McGeer, James C., E-mail: jmcgeer@wlu.ca

    2016-04-15

    Highlights: • Exposure to 18 nM waterborne Cd induced plasma Ca loss that recovered by day 30 for lake whitefish but not brown trout. • Ucrit measured after an initial swim to 85% of Ucrit and a 30 min rest period was reduced in 18 nM Cd exposed fish compared to controls. • Swimming to 85% of Ucrit resulted in decreased muscle glycogen and increased lactate that was not recovered in the 30 min recovery period. • Second swim impairment is not related to metabolic processes in white muscle. - Abstract: This study investigates the effect of chronic Cd exposure on the ability to perform repeat swim challenges in brown trout (Salmo trutta) and lake whitefish (Coregonus clupeaformis). Fish were exposed to waterborne Cd (18 nM) in moderately hard water (120 mg L{sup −1} CaCO{sub 3}) for 30 days. This level of exposure has been shown to cause sublethal physiological disruption and acclimation responses but no impairment of sustained swimming capacity (U{sub crit}) in single swim challenges. Swim trials were done over the course of the exposure and each one consisted of an initial swim to 85% of the U{sub crit} of control fish, a 30 min recovery period and finally a second swim challenge to determine U{sub crit}. Plasma and tissue samples were collected before and after each of the swim periods. As expected from previous studies, Cd exposure resulted in significant accumulation of Cd in gills, liver and kidney but not in white muscle. Exposure also induced a loss of plasma Ca followed by subsequent recovery (in lake whitefish but not brown trout) with few mortalities (100% survival for lake whitefish and 93% for brown trout). Both control and exposed fish swam to 85% of the single swim U{sub crit} and no differences in performance were seen. The Ucrit of unexposed controls in the second swim challenges were not different from the single swim Ucrit. However, second swim performance was significantly reduced in Cd exposed fish, particularly after a week of exposure

  14. Repeated exposure to media violence is associated with diminished response in an inhibitory frontolimbic network.

    Science.gov (United States)

    Kelly, Christopher R; Grinband, Jack; Hirsch, Joy

    2007-12-05

    Media depictions of violence, although often claimed to induce viewer aggression, have not been shown to affect the cortical networks that regulate behavior. Using functional magnetic resonance imaging (fMRI), we found that repeated exposure to violent media, but not to other equally arousing media, led to both diminished response in right lateral orbitofrontal cortex (right ltOFC) and a decrease in right ltOFC-amygdala interaction. Reduced function in this network has been previously associated with decreased control over a variety of behaviors, including reactive aggression. Indeed, we found reduced right ltOFC responses to be characteristic of those subjects that reported greater tendencies toward reactive aggression. Furthermore, the violence-induced reduction in right ltOFC response coincided with increased throughput to behavior planning regions. These novel findings establish that even short-term exposure to violent media can result in diminished responsiveness of a network associated with behaviors such as reactive aggression.

  15. The response of human nasal and bronchial organotypic tissue cultures to repeated whole cigarette smoke exposure.

    Science.gov (United States)

    Talikka, Marja; Kostadinova, Radina; Xiang, Yang; Mathis, Carole; Sewer, Alain; Majeed, Shoaib; Kuehn, Diana; Frentzel, Stefan; Merg, Celine; Geertz, Marcel; Martin, Florian; Ivanov, Nikolai V; Peitsch, Manuel C; Hoeng, Julia

    2014-01-01

    Exposure to cigarette smoke (CS) is linked to the development of respiratory diseases, and there is a need to understand the mechanisms whereby CS causes damage. Although animal models have provided valuable insights into smoking-related respiratory tract damage, modern toxicity testing calls for reliable in vitro models as alternatives for animal experimentation. We report on a repeated whole mainstream CS exposure of nasal and bronchial organotypic tissue cultures that mimic the morphological, physiological, and molecular attributes of the human respiratory tract. Despite the similar cellular staining and cytokine secretion in both tissue types, the transcriptomic analyses in the context of biological network models identified similar and diverse biological processes that were impacted by CS-exposed nasal and bronchial cultures. Our results demonstrate that nasal and bronchial tissue cultures are appropriate in vitro models for the assessment of CS-induced adverse effects in the respiratory system and promising alternative to animal experimentation.

  16. Repeated allergen exposure reduce early phase airway response and leukotriene release despite upregulation of 5-lipoxygenase pathways

    Directory of Open Access Journals (Sweden)

    Cui Zhi-Hua

    2012-03-01

    Full Text Available Abstract Background Allergen induced early phase airway response and airway plasma exudation are predominantly mediated by inflammatory mast cell mediators including histamine, cysteinyl leukotrienes (cysLTs and thromboxane A2 (TXA2. The aim of the present study was to evaluate whether repeated allergen exposure affects early phase airway response to allergen challenge. Methods A trimellitic anhydride (TMA sensitized guinea pig model was used to investigate the effects of low dose repeated allergen exposure on cholinergic airway responsiveness, early phase airway response and plasma exudation, as well as local airway production of mast cell derived cysteinyl leukotrienes and thromboxane B2 (TXB2 after allergen challenge. Results Repeated low dose allergen exposure increased cholinergic airway responsiveness. In contrast, early phase airway response and plasma exudation in response to a high-dose allergen challenge were strongly attenuated after repeated low dose allergen exposure. Inhibition of the airway response was unspecific to exposed allergen and independent of histamine receptor blocking. Furthermore, a significant reduction of cysteinyl leukotrienes and TXB2 was found in the airways of animals repeatedly exposed to a low dose allergen. However, in vitro stimulation of airway tissue from animals repeatedly exposed to a low dose allergen with arachidonic acid and calcium ionophore (A23187 induced production of cysteinyl leukotrienes and TXB2, suggesting enhanced activity of 5-lipoxygenase and cyclooxygenase pathways. Conclusions The inhibition of the early phase airway response, cysteinyl leukotriene and TXB2 production after repeated allergen exposure may result from unresponsive effector cells.

  17. The effects of repeated low-level blast exposure on hearing in marines

    Directory of Open Access Journals (Sweden)

    Lina R Kubli

    2017-01-01

    Full Text Available Background: The study evaluates a group of Military Service Members specialized in blast explosive training called “Breachers” who are routinely exposed to multiple low-level blasts while teaching breaching at the U.S. Marine Corps in Quantico Virginia. The objective of this study was to determine if there are any acute or long-term auditory changes due to repeated low-level blast exposures used in training. The performance of the instructor group “Breachers” was compared to a control group, “Engineers”. Methods: A total of 11 Breachers and four engineers were evaluated in the study. The participants received comprehensive auditory tests, including pure-tone testing, speech-in-noise (SIN measures, and central auditory behavioral and objective tests using early and late (P300 auditory evoked potentials over a period of 17 months. They also received shorter assessments immediately following the blast-exposure onsite at Quantico. Results: No acute or longitudinal effects were identified. However, there were some interesting baseline effects found in both groups. Contrary to the expected, the onsite hearing thresholds and distortion product otoacoustic emissions were slightly better at a few frequencies immediately after blast-exposure than measurements obtained with the same equipment weeks to months after each blast-exposure. Conclusions: To date, the current study is the most comprehensive study that evaluates the long-term effects of blast-exposure on hearing. Despite extensive testing to assess changes, the findings of this study suggest that the levels of current exposures used in this military training environment do not seem to have an obvious deleterious effect on hearing.

  18. The role of exposure history on HIV acquisition: insights from repeated low-dose challenge studies.

    Directory of Open Access Journals (Sweden)

    Roland R Regoes

    Full Text Available To assess the efficacy of HIV vaccine candidates or preventive treatment, many research groups have started to challenge monkeys repeatedly with low doses of the virus. Such challenge data provide a unique opportunity to assess the importance of exposure history for the acquisition of the infection. I developed stochastic models to analyze previously published challenge data. In the mathematical models, I allowed for variation of the animals' susceptibility to infection across challenge repeats, or across animals. In none of the studies I analyzed, I found evidence for an immunizing effect of non-infecting challenges, and in most studies, there is no evidence for variation in the susceptibilities to the challenges across animals. A notable exception was a challenge experiment by Letvin et al. Sci Translat Med (2011 conducted with the strain SIVsmE660. The challenge data of this experiment showed significant susceptibility variation from animal-to-animal, which is consistent with previously established genetic differences between the involved animals. For the studies which did not show significant immunizing effects and susceptibility differences, I conducted a power analysis and could thus exclude a very strong immunization effect for some of the studies. These findings validate the assumption that non-infecting challenges do not immunize an animal - an assumption that is central in the argument that repeated low-dose challenge experiments increase the statistical power of preclinical HIV vaccine trials. They are also relevant for our understanding of the role of exposure history for HIV acquisition and forecasting the epidemiological spread of HIV.

  19. Variability in prefrontal hemodynamic response during exposure to repeated self-selected music excerpts, a near-infrared spectroscopy study.

    Science.gov (United States)

    Moghimi, Saba; Schudlo, Larissa; Chau, Tom; Guerguerian, Anne-Marie

    2015-01-01

    Music-induced brain activity modulations in areas involved in emotion regulation may be useful in achieving therapeutic outcomes. Clinical applications of music may involve prolonged or repeated exposures to music. However, the variability of the observed brain activity patterns in repeated exposures to music is not well understood. We hypothesized that multiple exposures to the same music would elicit more consistent activity patterns than exposure to different music. In this study, the temporal and spatial variability of cerebral prefrontal hemodynamic response was investigated across multiple exposures to self-selected musical excerpts in 10 healthy adults. The hemodynamic changes were measured using prefrontal cortex near infrared spectroscopy and represented by instantaneous phase values. Based on spatial and temporal characteristics of these observed hemodynamic changes, we defined a consistency index to represent variability across these domains. The consistency index across repeated exposures to the same piece of music was compared to the consistency index corresponding to prefrontal activity from randomly matched non-identical musical excerpts. Consistency indexes were significantly different for identical versus non-identical musical excerpts when comparing a subset of repetitions. When all four exposures were compared, no significant difference was observed between the consistency indexes of randomly matched non-identical musical excerpts and the consistency index corresponding to repetitions of the same musical excerpts. This observation suggests the existence of only partial consistency between repeated exposures to the same musical excerpt, which may stem from the role of the prefrontal cortex in regulating other cognitive and emotional processes.

  20. Effects of single and repeated exposure to biocidal active substances on the barrier function of the skin in vitro

    NARCIS (Netherlands)

    Buist, H.E.; Sandt, J.J.M. van de; Burgsteden, J.A. van; Heer, C. de

    2005-01-01

    The dermal route of exposure is important in worker exposure to biocidal products. Many biocidal active substances which are used on a daily basis may decrease the barrier function of the skin to a larger extent than current risk assessment practice addresses, due to possible skin effects of repeate

  1. Effects of single and repeated exposure to biocidal active substances on the barrier function of the skin in vitro

    NARCIS (Netherlands)

    Buist, H.E.; Sandt, J.J.M. van de; Burgsteden, J.A. van; Heer, C. de

    2005-01-01

    The dermal route of exposure is important in worker exposure to biocidal products. Many biocidal active substances which are used on a daily basis may decrease the barrier function of the skin to a larger extent than current risk assessment practice addresses, due to possible skin effects of repeate

  2. Repeated cocaine exposure increases fast-spiking interneuron excitability in the rat medial prefrontal cortex.

    Science.gov (United States)

    Campanac, Emilie; Hoffman, Dax A

    2013-06-01

    The medial prefrontal cortex plays a key role in cocaine addiction. However, how chronic cocaine exposure affects cortical networks remains unclear. Most studies have focused on layer 5 pyramidal neurons (the circuit output), while the response of local GABAergic interneurons to cocaine remains poorly understood. Here, we recorded from fast-spiking interneurons (FS-IN) after repeated cocaine exposure and found altered membrane excitability. After cocaine withdrawal, FS-IN showed an increase in the number of spikes evoked by positive current injection, increased input resistance, and decreased hyperpolarization-activated current. We also observed a reduction in miniature excitatory postsynaptic currents, whereas miniature inhibitory postsynaptic current activity was unaffected. We show that, in animals with cocaine history, dopamine receptor D(2) activation is less effective in increasing FS-IN intrinsic excitability. Interestingly, these alterations are only observed 1 wk or more after the last cocaine exposure. This suggests that the dampening of D(2)-receptor-mediated response may be a compensatory mechanism to rein down the excitability of FS-IN.

  3. Assessing variability and comparing short-term biomarkers of styrene exposure using a repeated measurements approach.

    Science.gov (United States)

    Fustinoni, S; Manini, P; Campo, L; De Palma, G; Andreoli, R; Mutti, A; Bertazzi, P A; Rappaport, S M

    2010-01-15

    The aim of this work is to compare several short-term biomarkers of styrene exposure, namely urinary styrene (StyU), mercapturic acids (M1+M2), mandelic acid (MA), phenylglyoxylic acid (PGA), phenylglycine (PHG), and 4-vinylphenol conjugates (VP), for use as biomarkers of exposure in epidemiologic studies. A repeated measurements protocol (typically 4 measurements per worker over 6 weeks) was applied to measure airborne styrene (StyA) and urinary biomarkers in 10 varnish and 8 fiberglass reinforced plastic workers. Estimated geometric mean personal exposures to StyA were 2.96mg/m(3) in varnish workers and 15.7mg/m(3) in plastic workers. The corresponding levels of StyU, M1+M2, MA, PGA, MA+PGA, PHG and VP were 5.13microg/L, 0.111, 38.2, 22.7, 62.6, 0.978, and 3.97mg/g creatinine in varnish workers and 8.38microg/L, 0.303, 146, 83.4, 232, 2.85 and 3.97mg/g creatinine in plastic workers. Within-worker (sigma(wY)(2)) and between-worker (sigma(bY)(2)) variance components were estimated from the log-transformed data as were the corresponding fold ranges containing 95% of the respective lognormal distributions of daily levels ((w)R(0.95)) and subject-specific mean levels ((b)R(0.95)). Estimates of (w)R(0.95) (range: 4-26) were generally smaller than those of (b)R(0.95) (range: 5-790) for both environmental and biological markers; this indicates that exposures varied much more between workers than within workers in these groups. Since attenuation bias in an estimated exposure-response relationship increases with the variance ratio lambda=sigma(wY)(2)/sigma(bY)(2), we estimated values of lambda for all exposure measures in our study. Values of lambda were typically much less than one (median=0.220) and ranged from 0.089 for M1+M2 in plastic workers to 1.38 for PHG in varnish workers. Since values of lambda were 0.147 and 0.271 for StyA in varnish workers and plastic workers, respectively, compared to 0.178 and 0.210 for MA in the same groups, our results suggest that either

  4. Repeated exposure to iron oxide nanoparticles causes testicular toxicity in mice.

    Science.gov (United States)

    Sundarraj, Kiruthika; Manickam, Vijayprakash; Raghunath, Azhwar; Periyasamy, Madhivadhani; Viswanathan, Mangala Priya; Perumal, Ekambaram

    2017-02-01

    The aim of this study was to determine whether repeated exposure to iron oxide nanoparticles (Fe2 O3 -NPs) could be toxic to mice testis. Fe2 O3 -NPs (25 and 50 mg/kg) were intraperitoneally administered into mice once a week for 4 weeks. Our study showed that Fe2 O3 -NPs have the ability to cross the blood-testis barrier to get into the testis. The findings showed that exposure resulted in the accumulation of Fe2 O3 -NPs which was evidenced from the iron content and accumulation in the testis. Furthermore, 25 and 50 mg/kg Fe2 O3 -NPs administration increased the reactive oxygen species, lipid peroxidation, protein carbonyl content, glutathione peroxidase activity, and nitric oxide levels with a concomitant decrease in the levels of antioxidants-superoxide dismutase, catalase, glutathione, and vitamin C. Increased expression of Bax, cleaved-caspase-3, and cleaved-PARP confirms apoptosis. Serum testosterone levels increased with increased concentration of Fe2 O3 -NPs exposure. In addition, the histopathological lesions like vacuolization, detachment, and sloughing of germ cells were also observed in response to Fe2 O3 -NPs treatment. The data from our study entailed that testicular toxicity caused by Fe2 O3 -NPs exposure may be associated with Fe2 O3 -NPs accumulation leading to oxidative stress and apoptosis. Therefore, precautions should be taken in the safe use of Fe2 O3 -NPs to avoid complications in the fertility of males. Further research will unravel the possible molecular mechanisms on testicular toxicity of Fe2 O3 -NPs. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 594-608, 2017.

  5. The hidden price of repeated traumatic exposure: Different cognitive deficits in different first-responders

    Directory of Open Access Journals (Sweden)

    Einat eLevy-Gigi

    2014-08-01

    Full Text Available Studies on first responders who are repeatedly exposed to traumatic events report low levels of PTSD symptoms and diagnosis. However, neuroimaging and behavioral studies show that traumatic exposure is associated with brain and cognitive dysfunctions. Taking together it may suggest that traumatic exposure have a price, which is not sufficiently defined by the standard PTSD measures. In a recent study we revealed that similar to individuals with PTSD, non-PTSD highly exposed firefighters display a selective impairment in hippocampal related functions. In the current study we aimed to test whether different first responders display a similar impairment. We concentrated on unique populations of active duty firefighters and criminal scene-investigators (CSI police, who are frequently exposed to similar levels and types of traumatic events, and compared them to civilian matched-controls with no history of trauma-exposure. We used a hippocampal dependent cue-context reversal paradigm, which separately evaluates reversal of negative and positive outcomes of cue and context related information. We predicted and found that all participants were equally able to acquire and retain stimulus-outcome associations. However, there were significant differences in reversal learning between the groups. Performance among firefighters replicated our prior findings; they struggled to learn that a previously negative context is later associated with a positive outcome. CSI police on the other hand showed a selective impairment in reversing the outcome of a negative cue. Hence after learning that a specific cue is associated with a negative outcome, they could not learn that later it is associated with a positive outcome. Performance in both groups did not correlate with levels of PTSD, anxiety, depression or behavioral inhibition symptoms. The results provide further evidence of the hidden price of traumatic exposure, suggesting that this price may differ as a

  6. Perfectionism Affects Blood Pressure in Response to Repeated Exposure to Stress.

    Science.gov (United States)

    Albert, Phebe; Rice, Kenneth G; Caffee, Lauren

    2016-04-01

    This pilot study examined the effects of perfectionism on blood pressure (BP) in response to repeated exposure to mental arithmetic stressors. College students (N = 30) in a laboratory setting were administered a series of challenging mathematical tasks. BP was measured at baseline and after each task. Multilevel modelling analyses revealed that BP tended to decline over the course of the mathematical tasks. However, higher levels of performance standards predicted relatively stable levels of systolic BP, whereas moderate and lower levels of standards predicted declines in systolic BP. Higher levels of self-critical perfectionism predicted generally sustained levels of diastolic BP, with moderate and low self-criticism predicting declines in diastolic BP during the repeated stressors. These preliminary results suggest that students with higher levels of perfectionism may be at risk for physiological problems associated with stress reactivity, perhaps especially so in situations in which they experience persistent stress. Although results were qualified by a relatively small sample size, effects were statistically significant and supported the importance of examining the short-term and long-term implications of the effects of perfectionism on cardiovascular function and the different implications of elevations in systolic and diastolic BP.

  7. Increases in fruit intakes in older low consumers of fruit following two community-based repeated exposure interventions.

    Science.gov (United States)

    Appleton, K M

    2013-03-14

    The present study investigated the value of two repeated exposure interventions for increasing intakes of fruit in older people. A total of ninety-five participants (aged 65 years and over) were randomised to receive either one (E1), five (E5) or five plus (E5+) exposures to fruit over a 5-week period. Fruit exposures occurred in community-based church and social groups, through fruit-tasting sessions involving familiar fruits and novel fruit products and dishes (E1, E5, E5+), and through fruit provision (E5+). Daily intakes of fruit and vegetables were assessed before and after all interventions. Liking for all fruits was also measured during repeated exposure (E5, E5+). In low consumers of fruit (one portion/d or less), fruit intakes increased significantly in the repeated exposure groups (E5, E5+) (t(30) = 5·79, Polder low consumers of fruit, although no benefits of additional fruit provision were found. Repeated exposure was also easy to implement, of low cost and enjoyable.

  8. Repeated Exposure to Dissection Does Not Influence Students’ Attitudes towards Human Body Donation for Anatomy Teaching

    Directory of Open Access Journals (Sweden)

    Philip Maseghe Mwachaka

    2016-01-01

    Full Text Available The use of unclaimed bodies for anatomical dissection has been the main method of instruction at our institution. There is however a shortage of cadavers for dissection given the increase in the number of medical schools as well as in the number of students enrolling in these schools. This shortage could be mitigated by having voluntary human body donation programs. This study aimed at assessing the attitudes of medical students and surgical residents towards body donation for anatomy learning. We conducted an online survey involving 72 first-year medical students and 41 surgical residents at University of Nairobi who had completed one year of anatomy dissection. For the medical students, this was their first dissection experience while it was the second exposure for the surgery trainees. Most of the surgical trainees (70.7% and medical students (68.1% were opposed to self-body donation. This was mainly due to cultural (37% and religious (20% barriers. Surprisingly, of those not willing to donate themselves, 67.9% (82.8% surgical trainees, 59.2% medical students would recommend the practice to other people. Exposure to repeated dissection does not change the perceptions towards body donation. It is noteworthy that culture and religion rank high as clear barriers amongst this “highly informed” group of potential donors.

  9. Occupational hazards of traditional healers: repeated unprotected blood exposures risk infectious disease transmission.

    Science.gov (United States)

    Audet, Carolyn M; Salato, José; Blevins, Meridith; Silva, Wilson; González-Calvo, Lázaro; Vermund, Sten H; Gaspar, Felisbela

    2016-11-01

    Healers provide support for acute and chronic illnesses in rural Mozambique, such as socially acceptable traditional 'vaccinations' (subcutaneous cuts in the skin to rub herbs directly into the bloody lesion). We aimed to document the frequency of blood exposure by traditional practitioners in Mozambique. We conducted surveys with a simple random sample of 236 traditional healers in Zambézia province. Chi-square and Wilcoxon rank-sum tests were used to compare 'injection' behaviours across districts. Healers treated a median of eight patients in the past month (IQR: 4-15). About 75% conducted 'injections'. These healers 'injected' a median of four patients (IQR: 1-8), used a new razor a median of three times (IQR: 1-8), and almost never used gloves. Lifetime blood exposures among those who provided 'injections' during treatments were estimated to be 1758 over a healer's career. The majority of healers are exposed repeatedly to patient blood. Given the high prevalence of HIV, hepatitis B and C virus, and other blood-borne agents, specific healer practices are an occupational hazard and reuse of razors is risky for their clients. © 2016 John Wiley & Sons Ltd.

  10. Repeated exposure of acidic beverages on esthetic restorative materials: An in-vitro surface microhardness study.

    Science.gov (United States)

    Xavier, Arun M; Sunny, Steffy M; Rai, Kavita; Hegde, Amitha M

    2016-07-01

    A manifold increase in the consumption of aerated beverages has witnessed a twin increase in tooth wear and raised demand for esthetic restorative materials. This study aimed to evaluate the surface microhardness changes of esthetic restorative materials following treatment with aerated beverages in an in-vitro situation. The initial surface microhardness of the restorative materials GC Fuji II LC, GC Fuji IX, Nano Glass ionomer, Resin and Nano composite was recorded. These materials were studied under 3 groups that included those exposed to the acidic beverages daily, weekly once in a month and those that had no exposures at all. The final surface microhardness of the materials was recorded following experimentation and was subjected to statistical comparisons. The restorative materials were compared for their surface microhardness changes following respective treatments using the T-test and One-way ANOVA analysis. Inter-comparisons between the groups showed statistical significance (pmaterials revealed surface microhardness loss; the maximum reduction noticed with the Nano glass ionomer cement tested (pmaterials markedly reduced upon repeated exposures with acidic beverages; the product with phosphoric acid producing the maximum surface microhardness loss. Restorative materials, acidic beverages, surface microhardness, resin composites, glass ionomers.

  11. Repeated Exposure to Dissection Does Not Influence Students' Attitudes towards Human Body Donation for Anatomy Teaching.

    Science.gov (United States)

    Mwachaka, Philip Maseghe; Mandela, Pamela; Saidi, Hassan

    2016-01-01

    The use of unclaimed bodies for anatomical dissection has been the main method of instruction at our institution. There is however a shortage of cadavers for dissection given the increase in the number of medical schools as well as in the number of students enrolling in these schools. This shortage could be mitigated by having voluntary human body donation programs. This study aimed at assessing the attitudes of medical students and surgical residents towards body donation for anatomy learning. We conducted an online survey involving 72 first-year medical students and 41 surgical residents at University of Nairobi who had completed one year of anatomy dissection. For the medical students, this was their first dissection experience while it was the second exposure for the surgery trainees. Most of the surgical trainees (70.7%) and medical students (68.1%) were opposed to self-body donation. This was mainly due to cultural (37%) and religious (20%) barriers. Surprisingly, of those not willing to donate themselves, 67.9% (82.8% surgical trainees, 59.2% medical students) would recommend the practice to other people. Exposure to repeated dissection does not change the perceptions towards body donation. It is noteworthy that culture and religion rank high as clear barriers amongst this "highly informed" group of potential donors.

  12. Repeated exposure to media violence is associated with diminished response in an inhibitory frontolimbic network.

    Directory of Open Access Journals (Sweden)

    Christopher R Kelly

    Full Text Available BACKGROUND: Media depictions of violence, although often claimed to induce viewer aggression, have not been shown to affect the cortical networks that regulate behavior. METHODOLOGY/PRINCIPAL FINDINGS: Using functional magnetic resonance imaging (fMRI, we found that repeated exposure to violent media, but not to other equally arousing media, led to both diminished response in right lateral orbitofrontal cortex (right ltOFC and a decrease in right ltOFC-amygdala interaction. Reduced function in this network has been previously associated with decreased control over a variety of behaviors, including reactive aggression. Indeed, we found reduced right ltOFC responses to be characteristic of those subjects that reported greater tendencies toward reactive aggression. Furthermore, the violence-induced reduction in right ltOFC response coincided with increased throughput to behavior planning regions. CONCLUSIONS: These novel findings establish that even short-term exposure to violent media can result in diminished responsiveness of a network associated with behaviors such as reactive aggression.

  13. Respiratory toxicity of repeated exposure to particles produced by traffic and sugar cane burning.

    Science.gov (United States)

    Mazzoli-Rocha, Flavia; Carvalho, Giovanna M C; Lanzetti, Manuella; Valença, Samuel S; Silva, Luiz F F; Saldiva, Paulo H N; Zin, Walter A; Faffe, Débora S

    2014-01-15

    We compared the toxicity of subchronic exposure to equivalent masses of particles from sugar cane burning and traffic. BALB/c mice received 3 intranasal instillations/week during 1, 2 or 4 weeks of either distilled water (C1, C2, C4) or particles (15μg) from traffic (UP1, UP2, UP4) or biomass burning (BP1, BP2, BP4). Lung mechanics, histology and oxidative stress were analyzed 24h after the last instillation. In all instances UP and BP groups presented worse pulmonary elastance, airway and tissue resistance, alveolar collapse, bronchoconstriction and macrophage influx into the lungs than controls. UP4, BP2 and BP4 presented more alveolar collapse than UP1 and BP1, respectively. UP and BP had worse bronchial and alveolar lesion scores than their controls; BP4 had greater bronchial lesion scores than UP4. Catalase was higher in UP4 and BP4 than in C4. In conclusion, biomass particles were more toxic than those from traffic after repeated exposures.

  14. The physiological consequences of exposure to chronic, sublethal waterborne nickel in rainbow trout (Oncorhynchus mykiss): exercise vs resting physiology.

    Science.gov (United States)

    Pane, Eric F; Haque, Aziz; Goss, Greg G; Wood, Chris M

    2004-03-01

    In rainbow trout (Oncorhynchus mykiss), following chronic (42 day) exposure to both 384 microg Ni l(-1) and 2034 microg Ni l(-1), Ni accumulation was greatest in the gill, kidney and plasma, with the plasma as the main sink for Ni. Indeed, trapped plasma analysis revealed that extensive loading of Ni in the plasma accounted for substantial percentages of accumulated Ni in several tissues including the liver and heart. Accumulated Ni in the gill and kidney was less dependent on plasma Ni concentration, suggesting a more intracellular accumulation of Ni in these tissues. We present evidence for a clear, persistent cost of acclimation to chronic, sublethal Ni exposure. Chronic (40-99 day) exposure to sublethal waterborne Ni (243-394 microg Ni l(-1); approximately 1% of the 96 h LC(50)) impaired the exercise physiology, but not the resting physiology, of rainbow trout. Ni acted as a limiting stressor, decreasing maximal rates of oxygen consumption (MO2,max) during strenuous exercise in trout exposed for 34 days to sublethal Ni. This drop in high-performance gas exchange was attributed mainly to a reduction in relative branchial diffusing capacity (D(rel)) caused by thickening of secondary lamellae. Morphometric analysis of the gills of chronically exposed fish revealed overall swelling of secondary lamellae, as well as hypertrophic respiratory epithelia within secondary lamellae. Additionally, contraction of the lamellar blood pillar system and narrowing of interlamellar water channels occurred, possibly contributing to decreased high-performance gas exchange. Decreased aerobic capacity persisted in fish previously exposed to nickel despite a clean-water exposure period of 38 days and an almost complete depuration of gill Ni, suggesting that extrabranchial mechanisms of chronic Ni toxicity may also be important. Chronic impairment of such a dynamically active and critical organ as the gill may depress the overall fitness of a fish by impairing predator avoidance, prey

  15. The effects of chronic cadmium exposure on repeat swimming performance and anaerobic metabolism in brown trout (Salmo trutta) and lake whitefish (Coregonus clupeaformis).

    Science.gov (United States)

    Cunningham, Jessie L; McGeer, James C

    2016-04-01

    This study investigates the effect of chronic Cd exposure on the ability to perform repeat swim challenges in brown trout (Salmo trutta) and lake whitefish (Coregonus clupeaformis). Fish were exposed to waterborne Cd (18nM) in moderately hard water (120mgL(-1) CaCO3) for 30 days. This level of exposure has been shown to cause sublethal physiological disruption and acclimation responses but no impairment of sustained swimming capacity (Ucrit) in single swim challenges. Swim trials were done over the course of the exposure and each one consisted of an initial swim to 85% of the Ucrit of control fish, a 30min recovery period and finally a second swim challenge to determine Ucrit. Plasma and tissue samples were collected before and after each of the swim periods. As expected from previous studies, Cd exposure resulted in significant accumulation of Cd in gills, liver and kidney but not in white muscle. Exposure also induced a loss of plasma Ca followed by subsequent recovery (in lake whitefish but not brown trout) with few mortalities (100% survival for lake whitefish and 93% for brown trout). Both control and exposed fish swam to 85% of the single swim Ucrit and no differences in performance were seen. The Ucrit of unexposed controls in the second swim challenges were not different from the single swim Ucrit. However, second swim performance was significantly reduced in Cd exposed fish, particularly after a week of exposure where 31% and 38% reductions were observed for brown trout and lake whitefish respectively. Swimming to 85% Ucrit resulted in metabolic expenditure with little recovery after 30min. Few differences were observed between control and Cd exposed fish with the exception of a reduction in resting white muscle ATP stores of Cd exposed fish after 1 week of exposure. The results show that chronic sublethal Cd exposure results in an impairment of swimming ability in repeat swim challenges but this impairment is generally not related to metabolic processes

  16. Variability in prefrontal hemodynamic response during exposure to repeated self-selected music excerpts, a near-infrared spectroscopy study.

    Directory of Open Access Journals (Sweden)

    Saba Moghimi

    Full Text Available Music-induced brain activity modulations in areas involved in emotion regulation may be useful in achieving therapeutic outcomes. Clinical applications of music may involve prolonged or repeated exposures to music. However, the variability of the observed brain activity patterns in repeated exposures to music is not well understood. We hypothesized that multiple exposures to the same music would elicit more consistent activity patterns than exposure to different music. In this study, the temporal and spatial variability of cerebral prefrontal hemodynamic response was investigated across multiple exposures to self-selected musical excerpts in 10 healthy adults. The hemodynamic changes were measured using prefrontal cortex near infrared spectroscopy and represented by instantaneous phase values. Based on spatial and temporal characteristics of these observed hemodynamic changes, we defined a consistency index to represent variability across these domains. The consistency index across repeated exposures to the same piece of music was compared to the consistency index corresponding to prefrontal activity from randomly matched non-identical musical excerpts. Consistency indexes were significantly different for identical versus non-identical musical excerpts when comparing a subset of repetitions. When all four exposures were compared, no significant difference was observed between the consistency indexes of randomly matched non-identical musical excerpts and the consistency index corresponding to repetitions of the same musical excerpts. This observation suggests the existence of only partial consistency between repeated exposures to the same musical excerpt, which may stem from the role of the prefrontal cortex in regulating other cognitive and emotional processes.

  17. Repeated exposure to odors induces affective habituation of perception and sniffing

    Directory of Open Access Journals (Sweden)

    Camille eFerdenzi

    2014-04-01

    Full Text Available Olfactory perception, and especially hedonic evaluation of odors, is highly flexible, but some mechanisms involved in this flexibility remain to be elucidated. In the present study we aimed at better understanding how repeated exposure to odors can affect their pleasantness. We tested the hypothesis of an affective habituation to the stimuli, namely a decrease of emotional intensity over repetitions. More specifically, we tested whether this effect is subject to inter-individual variability and whether it can also be observed at the olfactomotor level. Twenty-six participants took part in the experiment during which they had to smell two odorants, anise and chocolate, presented twenty times each. On each trial, sniff duration and volume were recorded and paired with ratings of odor pleasantness and intensity. For each smell, we distinguished between likers and dislikers, namely individuals giving positive and negative initial hedonic evaluations. Results showed a significant decrease in pleasantness with time when the odor was initially pleasant (likers, while unpleasantness remained stable or slightly decreased when the odor was initially unpleasant (dislikers. This deviation towards neutrality was interpreted as affective habituation. This effect was all the more robust as it was observed for both odors and corroborated by sniffing, an objective measurement of odor pleasantness. Affective habituation to odors can be interpreted as an adaptive response to stimuli that prove over time to be devoid of positive or negative outcome on the organism. This study contributes to a better understanding of how olfactory preferences are shaped through exposure, depending on the individual’s own initial perception of the odor.

  18. Impact of product information and repeated exposure on consumer liking, sensory perception and concept associations of local apple juice

    DEFF Research Database (Denmark)

    Stolzenbach, Sandra; Bredie, Wender Laurentius Petrus; Christensen, Rune Haubo Bojesen

    2013-01-01

    The impact of product information and repeated exposure of local apple juice on consumer liking, sensory perception and concept associations was studied. Findings showed that consumers had high expectations towards the studied local apples juices. Consequently, the liking for the local apple juic...

  19. Repeated exposures to cobalt or chromate on the hands of patients with hand eczema and contact allergy to that metal

    DEFF Research Database (Denmark)

    Nielsen, N H; Kristiansen, J; Borg, L

    2000-01-01

    The present study aimed at evaluating the effects of daily repeated exposures to low cobalt or chromate concentrations on the hands of patients with hand eczema and cobalt or chromate allergy. For 2 weeks, the patients immersed a finger for 10 min daily into the appropriate metal salt solution in...

  20. Effect of repeated and prolonged exposure to low concentrations of Low Molecular Weight chemicals on local lymph node responses

    NARCIS (Netherlands)

    Jong WH de; Beek M ter; Veenman C; Klerk A de; Loveren H van; TOX

    2006-01-01

    The results of the local lymph node assay are not for all compounds useful as starting point for a quantitative risk assessment. This study describes the effects after repeated exposure of the skin to a concentration of a sensitizer below the threshold used in the local lymph node assay. Positive re

  1. Effects of moxifloxacin exposure on the conjunctival flora and antibiotic resistance profile following repeated intravitreal injections

    Institute of Scientific and Technical Information of China (English)

    Mustafa; Atas; Burhan; Baskan; Ayse; zkse; Fatma; Mutlu; Sarιgüzel; Süleyman; Demircan; Emine; Pangal

    2014-01-01

    AIM:To evaluate the effects of moxifloxacin exposure on the conjunctival flora and antibiotic resistance profile following repeated intravitreal injections.METHODS:Seventy-two eyes of 36 patients [36 eyes in control group, 36 eyes in intravitreal injection(IVI) group]were enrolled in the study. All the eyes had at least one IVI and had diabetic macular edema(DME) or age-related macular degeneration(ARMD). Moxifloxacin was prescribed to all the patients four times a day for five days following injection. Conjunctival cultures were obtained from the lower fornix via standardized technique with every possible effort made to minimize contamination from the lids, lashes, or skin. Before the application of any ophthalmic medication, conjunctival cultures were obtained from both eyes using sterile cotton culture. An automated microbiology system was used to identify the growing bacteria and determine antibiotic sensitivity.RESULTS:The bacterial cultures were isolated from 72 eyes of 36 patients, sixteen of whom patients(44.4%)were male and twenty(55.6%) were female. Average age was 68.4 ±9.0(range 50-86). The average number of injections before taking cultures was 3.1+1.0. Forty-eight(66.7%) of 72 eyes had at least one significant organism.There was no bacterial growth in 8(20.5%) of IVI eyes and in 16(44.4%) of control eyes(P =0.03). Of the bacteria isolated from culture, 53.8% of coagulase negative staphylococci(CoNS) in IVI eyes and 47.2%CoNS in control eyes. This difference between IVI eyes and control eyes about bacteria isolated from culture was not statistically significant(P =0.2). Eleven of 25 bacteria(44.0%) isolated from IVI eyes and 11(57.9%) of 19 bacteria isolated from control eyes were resistant to oxacillin. The difference in frequency of moxifloxacine resistance between two groups was not statistically significant(12.0% in IVI eyes and 21.1% in control eyes)(P =0.44). There were no cases of resistance to vancomycin, teicoplanin and linezolid

  2. Repeated exposure of adult rats to transient oxidative stress induces various long-lasting alterations in cognitive and behavioral functions.

    Directory of Open Access Journals (Sweden)

    Yoshio Iguchi

    Full Text Available Exposure of neonates to oxidative stress may increase the risk of psychiatric disorders such as schizophrenia in adulthood. However, the effects of moderate oxidative stress on the adult brain are not completely understood. To address this issue, we systemically administrated 2-cyclohexen-1-one (CHX to adult rats to transiently reduce glutathione levels. Repeated administration of CHX did not affect the acquisition or motivation of an appetitive instrumental behavior (lever pressing rewarded by a food outcome under a progressive ratio schedule. In addition, response discrimination and reversal learning were not affected. However, acute CHX administration blunted the sensitivity of the instrumental performance to outcome devaluation, and this effect was prolonged in rats with a history of repeated CHX exposure, representing pro-depression-like phenotypes. On the other hand, repeated CHX administration reduced immobility in forced swimming tests and blunted acute cocaine-induced behaviors, implicating antidepressant-like effects. Multivariate analyses segregated a characteristic group of behavioral variables influenced by repeated CHX administration. Taken together, these findings suggest that repeated administration of CHX to adult rats did not cause a specific mental disorder, but it induced long-term alterations in behavioral and cognitive functions, possibly related to specific neural correlates.

  3. Change in tensile properties of neoprene and nitrile gloves after repeated exposures to acetone and thermal decontamination.

    Science.gov (United States)

    Gao, Pengfei; Tomasovic, Beth

    2005-11-01

    This study investigated the change in tensile properties of neoprene and nitrile gloves after repeated cycles of exposure to acetone, followed by thermal decontamination. The glove was exposed to acetone (outer surface in contact with chemical), subjected to thermal decontamination, and tested for the tensile strength and the ultimate elongation. Thermal decontamination was carried out inside an oven for 16 hours at 100 degrees C. The exposure/decontamination procedure was repeated for a maximum of 10 cycles. For neoprene versus acetone, the mean tensile strength consistently decreased after each exposure/decontamination cycle. Multiple comparisons indicated that the mean tensile strengths between the new swatches and each exposure/decontamination group were significantly different (p 0.05). The mean tensile strength for the new swatches was 37.1 MPa and the mean tensile strength after nine exposure/decontamination cycles was 36.0 MPa, with a loss less than 3%. The largest single cycle loss for ultimate elongation occurred during the first exposure/decontamination cycle for both glove materials. In our previous study, decisions regarding the effectiveness of the decontamination process were based on having no discernible change in the breakthrough time and steady-state permeation rate. The results of this study indicate that the effectiveness of the decontamination process cannot be based on permeation parameters alone but must also take into account the change in physical properties.

  4. Androgen receptor gene CAG repeat length as modifier of the association between Persistent Organohalogen Pollutant exposure markers and semen characteristics

    DEFF Research Database (Denmark)

    Giwercman, Aleksander; Rylander, Lars; Rignell-Hydbom, Anna;

    2007-01-01

    OBJECTIVES: Exposure to persistent organohalogen pollutants was suggested to impair male reproductive function. A gene-environment interaction has been proposed. No genes modifying the effect of persistent organohalogen pollutants on reproductive organs have yet been identified. We aimed...... and morphology) and DNA fragmentation index (DFI) were determined. CAG and GGN repeat lengths were determined by direct sequencing of leukocyte DNA. RESULTS: A statistically significant interaction was found between the CB-153 group and CAG repeat category in relation to sperm concentration and total sperm count...

  5. Lipid Profile and Oxidative Stress Markers in Wistar Rats following Oral and Repeated Exposure to Fijk Herbal Mixture

    Directory of Open Access Journals (Sweden)

    Oluyomi Stephen Adeyemi

    2014-01-01

    Full Text Available This study determined the effect of the oral and repeated administration of Fijk herbal mixture on rat biochemical and morphological parameters. Twenty-four Wistar rats were distributed into four groups of 6. Group A served as control and received oral administration of distilled water daily. The experimental groups B, C, and D were daily and orally exposed to Fijk herbal mixture at 15, 30, and 45 mg/kg, respectively. Treatments lasted for 21 days. The rats were sacrificed under mild diethyl ether anesthesia 24 hr after cessation of treatment. The blood and liver samples were collected and used for the biochemical and morphological analyses. Oral exposure to Fijk caused elevated levels of rat plasma ALT, AST, triglycerides, LDL, and MDA. In contrast, rat plasma HDL, GSH, and ALP levels were lowered by Fijk oral exposure. Also, the herbal remedy caused a dose-dependent elevation in the plasma atherogenic index. The histopathology examinations of rat liver sections revealed inimical cellular alterations caused by repeated exposure to Fijk. Study provides evidence that oral and repeated exposure to Fijk in rats raised the atherogenic index and potentiated oxidative stress as well as hepatic injury.

  6. Changes on expected taste perception of probiotic and conventional yogurts made from goat milk after rapidly repeated exposure.

    Science.gov (United States)

    Costa, M P; Balthazar, C F; Franco, R M; Mársico, E T; Cruz, A G; Conte, C A

    2014-05-01

    Goat milk yogurt is an excellent source of fatty acids, protein, and minerals; however, it is not well accepted by many consumers, due to its typical flavor derived from caprylic, capric, and caproic acids present in this milk and dairy products. Recently, the repeated-exposure test has been used to increase the consumption of particular foods. This methodology has been used to increase children's willingness to eat food in some settings and has also been used to reduce sodium in soup. Based on these considerations, the aim of this study was to investigate whether repeated exposures may increase acceptance of both goat milk yogurt and probiotic goat milk yogurt. In a pre-exposure session, a total of 45 panelists (28 females and 17 males) from southeastern Brazil, who were not used to consuming dairy goat milk, evaluated the expected taste perception and the perceived liking after tasting 3 yogurt preparations. Then, consumers were randomly divided into 3 groups and participated in rapidly repeated exposure sessions performed within 6 d. Each panelist consumed only the yogurt that he or she would be exposed to. The day after the exposure sessions, all panelists returned to participate in the postexposure session and were asked to evaluate acceptance, familiarity, and the "goaty taste" characteristic of each yogurt. Regarding the expected liking before tasting, results showed higher expectations for cow milk yogurt compared with goat milk yogurt, which proved that consumers were not familiar with the goat milk yogurt. Likewise, only cow milk yogurt presented high acceptance and familiarity rates, confirming that these panelists were used to consuming cow milk products. With respect to the rapidly repeated exposure, 6 d were enough to significantly increase the consumers' familiarity with goat milk yogurt and probiotic goat milk yogurt. However, this method was not suitable to significantly increase the acceptance of such products. Nonetheless, a correlation existed

  7. Mediation of the Relationship between Maternal Phthalate Exposure and Preterm Birth by Oxidative Stress with Repeated Measurements across Pregnancy.

    Science.gov (United States)

    Ferguson, Kelly K; Chen, Yin-Hsiu; VanderWeele, Tyler J; McElrath, Thomas F; Meeker, John D; Mukherjee, Bhramar

    2017-03-01

    Mediation analysis is useful for understanding mechanisms and has been used minimally in the study of the environment and disease. We examined mediation of the association between phthalate exposure during pregnancy and preterm birth by oxidative stress. This nested case-control study of preterm birth (n = 130 cases, 352 controls) included women who delivered in Boston, Massachusestts, from 2006 through 2008. Phthalate metabolites and 8-isoprostane, an oxidative stress biomarker, were measured in urine from three visits in pregnancy. We applied four counterfactual mediation methods: method 1, utilizing exposure and mediator averages; method 2, using averages but allowing for an exposure-mediator interaction; method 3, incorporating longitudinal measurements of the exposure and mediator; and method 4, using longitudinal measurements and allowing for an exposure-mediator interaction. We observed mediation of the associations between phthalate metabolites and all preterm birth by 8-isoprostane, with the greatest estimated proportion mediated observed for spontaneous preterm births specifically. Fully utilizing repeated measures of the exposure and mediator improved precision of indirect (i.e., mediated) effect estimates, and including an exposure-mediator interaction increased the estimated proportion mediated. For example, for mono(2-ethyl-carboxy-propyl) phthalate (MECPP), a metabolite of di(2-ethylhexyl) phthalate (DEHP), the percent of the total effect mediated by 8-isoprostane increased from 47% to 60% with inclusion of an exposure-mediator interaction term, in reference to a total adjusted odds ratio of 1.67 or 1.48, respectively. This demonstrates mediation of the phthalate-preterm birth relationship by oxidative stress, and the utility of complex regression models in capturing mediated associations when repeated measures of exposure and mediator are available and an exposure-mediator interaction may exist. Citation: Ferguson KK, Chen YH, VanderWeele TJ, Mc

  8. Effects of acute versus repeated cocaine exposure on the expression of endocannabinoid signaling-related proteins in the mouse cerebellum

    OpenAIRE

    Ana ePalomino; Francisco Javier ePavon; Eduardo eBlanco Calvo; Antonia eSerrano; Sergio eArrabal; Patricia eRivera; Antonio eVargas; Ainhoa eBilbao; Leticia eRubio; Fernando eRodriguez de Fonseca; Juan eSuarez

    2014-01-01

    Growing awareness of cerebellar involvement in addiction is based on the cerebellum’s intermediary position between motor and reward, potentially acting as an interface between motivational and cognitive functions. Here, we examined the impact of acute and repeated cocaine exposure on the two main signaling systems in the mouse cerebellum: the endocannabinoid (eCB) and glutamate systems. To this end, we investigated whether eCB signaling-related gene and protein expression {cannabinoid recept...

  9. Inhibition of Voltage-Gated Calcium Channels After Subchronic and Repeated Exposure of PC12 Cells to Different Classes of Insecticides.

    Science.gov (United States)

    Meijer, Marieke; Brandsema, Joske A R; Nieuwenhuis, Desirée; Wijnolts, Fiona M J; Dingemans, Milou M L; Westerink, Remco H S

    2015-10-01

    We previously demonstrated that acute inhibition of voltage-gated calcium channels (VGCCs) is a common mode of action for (sub)micromolar concentrations of chemicals, including insecticides. However, because human exposure to chemicals is usually chronic and repeated, we investigated if selected insecticides from different chemical classes (organochlorines, organophosphates, pyrethroids, carbamates, and neonicotinoids) also disturb calcium homeostasis after subchronic (24 h) exposure and after a subsequent (repeated) acute exposure. Effects on calcium homeostasis were investigated with single-cell fluorescence (Fura-2) imaging of PC12 cells. Cells were depolarized with high-K(+) saline to study effects of subchronic or repeated exposure on VGCC-mediated Ca(2+) influx. The results demonstrate that except for carbaryl and imidacloprid, all selected insecticides inhibited depolarization (K(+))-evoked Ca(2+) influx after subchronic exposure (IC50's: approximately 1-10 µM) in PC12 cells. These inhibitory effects were not or only slowly reversible. Moreover, repeated exposure augmented the inhibition of the K(+)-evoked increase in intracellular calcium concentration induced by subchronic exposure to cypermethrin, chlorpyrifos, chlorpyrifos-oxon, and endosulfan (IC50's: approximately 0.1-4 µM). In rat primary cortical cultures, acute and repeated chlorpyrifos exposure also augmented inhibition of VGCCs compared with subchronic exposure. In conclusion, compared with subchronic exposure, repeated exposure increases the potency of insecticides to inhibit VGCCs. However, the potency of insecticides to inhibit VGCCs upon repeated exposure was comparable with the inhibition previously observed following acute exposure, with the exception of chlorpyrifos. The data suggest that an acute exposure paradigm is sufficient for screening chemicals for effects on VGCCs and that PC12 cells are a sensitive model for detection of effects on VGCCs. © The Author 2015. Published by Oxford

  10. Mitochondrial tolerance to single and repeat exposure to simulated sunlight in human epidermal and dermal skin cells.

    Science.gov (United States)

    Kelly, J; Murphy, J E J

    2016-12-01

    Sunlight represents the primary threat to mitochondrial integrity in skin given the unique nature of the mitochondrial genome and its proximity to the electron transport chain. The accumulation of mitochondrial DNA (mtDNA) mutations is a key factor in many human pathologies and this is linked to key roles of mitochondrial function in terms of energy production and cell regulation. The main objective of this study was to evaluate solar radiation induced changes in mitochondrial integrity, function and dynamics in human skin cells using a Q-Sun solar simulator to deliver a close match to the intensity of summer sunlight. Spontaneously immortalised human skin epidermal keratinocytes (HaCaT) and Human Dermal Fibroblasts (HDFn) were divided into two groups. Group A were irradiated once and Group B twice 7days apart and evaluated using cell survival, viability and mitochondrial membrane potential (MMP) and mass at 1, 4 and 7days post one exposure for Group A and 1, 4, 7 and 14days post second exposure for Group B. Viability and survival of HaCaT and HDFn cells decreased after repeat exposure to Simulated Sunlight Irradiation (SSI) with no recovery. HDFn cells showed no loss in MMP after one or two exposures to SSI compared to HaCaT cells which showed a periodic loss of MMP after one exposure with a repeat exposure causing a dramatic decrease from which cells did not recover. Mitochondrial Mass in exposed HDFn cells was consistent with control after one or two exposures to SSI; however mitochondrial mass was significantly decreased in HaCaT cells. Data presented here suggests that mitochondria in epidermal cells are more sensitive to sunlight damage compared to mitochondria in dermal cells, despite their origin, confirming a skin layer specific sensitivity to sunlight, but not as expected. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Effects of repeated exposure to malathion on growth, food consumption, and locomotor performance of the western fence lizard (Sceloporus occidentalis)

    Energy Technology Data Exchange (ETDEWEB)

    Holem, Ryan R. [University of Georgia, Savannah River Ecology Laboratory, Aiken, SC 29801 (United States); ENTRIX, Inc., Okemos, MI 48864 (United States); Hopkins, William A. [University of Georgia, Savannah River Ecology Laboratory, Aiken, SC 29801 (United States); Department of Fisheries and Wildlife Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061 (United States)], E-mail: hopkinsw@vt.edu; Talent, Larry G. [Natural Resource Ecology and Management, Oklahoma State University, Stillwater, OK 74078 (United States)

    2008-03-15

    Effects of repeated pollutant exposure on growth, locomotor performance, and behavior have rarely been evaluated in reptiles. We administered three doses of malathion (2.0, 20, or 100 mg/kg body weight) to western fence lizards (Sceloporus occidentalis) over an 81 day period. Eight and 23% mortality occurred at 20 and 100 mg/kg (p = 0.079) and 85% of lizards in the 100 mg/kg group exhibited clinical symptoms of poisoning. Growth, food consumption, body condition index, and terrestrial locomotor performance were not significantly influenced by malathion. However, arboreal sprint velocity was significantly reduced in lizards receiving 100 mg/kg. Fifty percent of lizards in the 100 mg/kg group also refused to sprint in the arboreal setting (p = 0.085). Based on these results, arboreal locomotor performance was the most sensitive metric of exposure we evaluated. Further study of compounds such as malathion is warranted due to highly variable application rates and exposure scenarios. - Repeated exposure of western fence lizards to malathion caused reduced arboreal performance and some mortality but growth, food consumption, and terrestrial performance were not affected.

  12. Effects of acute versus repeated cocaine exposure on the expression of endocannabinoid signaling-related proteins in the mouse cerebellum

    Directory of Open Access Journals (Sweden)

    Ana ePalomino

    2014-03-01

    Full Text Available Growing awareness of cerebellar involvement in addiction is based on the cerebellum’s intermediary position between motor and reward, potentially acting as an interface between motivational and cognitive functions. Here, we examined the impact of acute and repeated cocaine exposure on the two main signaling systems in the mouse cerebellum: the endocannabinoid (eCB and glutamate systems. To this end, we investigated whether eCB signaling-related gene and protein expression (CB1 receptors and enzymes that produce (DAGLα/β and NAPE-PLD and degrade (MAGL and FAAH eCB were altered. In addition, we analyzed the gene expression of relevant components of the glutamate signaling system (glutamate synthesizing enzymes LGA and KGA, mGluR3/5 metabotropic receptors, and NR1/2A/2B/2C-NMDA and GluR1/2/3/4-AMPA ionotropic receptor subunits and the gene expression of tyrosine hydroxylase (TH, the rate-limiting enzyme in catecholamine biosynthesis, because noradrenergic terminals innervate the cerebellar cortex. Results indicated that acute cocaine exposure decreased DAGLα expression, suggesting a down-regulation of 2-AG production, as well as gene expression of TH, KGA, mGluR3 and all ionotropic receptor subunits analyzed in the cerebellum. The acquisition of conditioned locomotion and sensitization after repeated cocaine exposure were associated with an increased NAPE-PLD/FAAH ratio, suggesting enhanced anandamide production, and a decreased DAGLβ/MAGL ratio, suggesting decreased 2-AG generation. Repeated cocaine also increased LGA gene expression but had no effect on glutamate receptors. These findings indicate that acute cocaine modulates the expression of the eCB and glutamate systems. Repeated cocaine results in normalization of glutamate receptor expression, although sustained changes in eCB is observed. We suggest that cocaine-induced alterations to cerebellar eCB should be considered when analyzing the adaptations imposed by psychostimulants that

  13. Repeated exposures to blue light-activated eosin Y enhance inactivation of E. faecalis biofilms, in vitro.

    Science.gov (United States)

    Marinic, Karlo; Manoil, Daniel; Filieri, Anna; Wataha, John C; Schrenzel, Jacques; Lange, Norbert; Bouillaguet, Serge

    2015-09-01

    In dentistry, antibacterial photodynamic therapy (a-PDT) has shown promising results for inactivating bacterial biofilms causing carious, endodontic and periodontal diseases. In the current study, we assessed the ability of eosin Y exposed to 3 irradiation protocols at inactivating Enterococcus faecalis biofilms, in vitro. E. faecalis biofilms formed on hydroxyapatite disks were incubated with eosin Y (10-80μM), then activated with blue light using different irradiation protocols. Biofilms exposed to continuous exposure were incubated for 40min before being light-activated for 960 s. For the intermittent exposure, biofilms were exposed 4 times to the light/photosensitizer combination (960 s total) without renewing the photosensitizer. For repeated a-PDT, the same light dose was delivered in a series of 4 irradiation periods separated by dark periods; fresh photosensitizer was added between each light irradiation. After treatment, bacteria were immediately labeled with LIVE/DEAD BacLight Bacterial Viability kit and viability was assessed by flow cytometry (FCM). Results were statistically analyzed using one-way ANOVA and Tukey multiple comparison intervals (α=0.05). The viability of E. faecalis biofilms exposed to 10μM eosin Y, was significantly reduced compared to controls (light only-eosin Y only). After a second exposure to blue light-activated eosin Y, viability significantly decreased from 58% to 12% whereas 6.5% of the bacterial biofilm remained live after a third exposure (p<0.05). Only 3.5% of the bacterial population survived after the fourth exposure. The results of this study indicate that blue light-activated eosin Y can photoinactivate E. faecalis biofilms grown on hydroxyapatite disks. Also, repeated exposures to blue light-activated eosin Y were shown to significantly improve efficacy. Further studies seem warranted to optimize the antibacterial activity of blue light-activated eosin Y on major oral pathogens. Copyright © 2015 Elsevier B.V. All

  14. Prediction of local irritant effects after repeated dermal and respiratory exposure to chemicals

    NARCIS (Netherlands)

    Rennen, M.A.J.; Nordheim, K.; Houben, G.F.; Heer, C. de

    2002-01-01

    Health risks resulting from occupational exposure to chemicals are controlled by the establishment of acceptable dermal and respiratory exposure levels. Due to a lack of route-specific toxicity data, acceptable levels are frequently established by means of route-to-route extrapolation. A pitfall in

  15. Prediction of local irritant effects after repeated dermal and respiratory exposure to chemicals

    NARCIS (Netherlands)

    Rennen, M.A.J.; Nordheim, K.; Houben, G.F.; Heer, C. de

    2002-01-01

    Health risks resulting from occupational exposure to chemicals are controlled by the establishment of acceptable dermal and respiratory exposure levels. Due to a lack of route-specific toxicity data, acceptable levels are frequently established by means of route-to-route extrapolation. A pitfall in

  16. NEUROBEHAVIORAL EFFECTS OF CHRONIC DIETARY AND REPEATED HIGH-LEVEL SPIKE EXPOSURE TO CHLORPYRIFOS IN RATS.

    Science.gov (United States)

    This study aimed to model long-term subtoxic human exposure to an organophosphorus pesticide, chlorpyrifos, and to examine the influence of that exposure on the response to intermittent high-dose acute challenges. Adult rats were maintained on a chlorpyrifos-containing diet to p...

  17. Changes of lead speciation and microbial toxicity in soil treated with repeated Pb exposure in the presence of BDE209.

    Science.gov (United States)

    Zhang, Rong; Zhang, Wei; Liu, Gao; Lin, Kuangfei; Fu, Rongbing

    2016-03-01

    Lead (Pb) and decabromodiphenyl ether (BDE209) are main pollutants at electric waste (e-waste) recycling sites (EWRSs), and their joint toxicological effects have received extensive attention. Frequently, soil pollution at EWRSs usually results from the occurrence of repeated single or multiple pollution events, with continuous impacts on soil microorganisms. Therefore, a laboratory incubation study was conducted to determine Pb bioavailability and microbial toxicity in repeated Pb-polluted soil in the presence of BDE209 for the first time. We evaluated the impacts of repetitive exposure trials on chemical fractions of Pb, and the results showed that repeated single Pb pollution event resulted in an increase of carbonates fraction of Pb, which was different from one-off single Pb exposure. Moreover, one-off Pb-treated groups exhibited higher I R (reduced partition index) values on day 30 and all treatments remained the same I R level at the end of incubation period. The parameters of microbial toxicity were well reflected by soil enzymes. During the entire incubation, the dehydrogenase and urease activities were significantly inhibited by Pb (P soil enzymes were clearly observed (P < 0.05 or 0.01). Such observations would provide useful information for ecological effects of Pb and BDE209 at EWRSs.

  18. Changes in resting-state brain function of pilots after hypoxic exposure based on methods for fALFF and ReHo analysis

    Directory of Open Access Journals (Sweden)

    Jie LIU

    2015-07-01

    Full Text Available Objective The objective of this study was to evaluate the basic changes in brain activity of pilots after hypoxic exposure with the use of resting-state functional magnetic resonance imaging (rs-fMRI and regional homogeneity (ReHo method. Methods Thirty healthy male pilots were successively subjected to normal and hypoxic exposure (with an oxygen concentration of 14.5%. Both the fALFF and ReHo methods were adopted to analyze the resting-state functional MRI data before and after hypoxic exposure of the subjects, the areas of the brain with fALFF and ReHo changes after hypoxic exposure were observed. Results  After hypoxic exposure, the pulse was 64.0±10.6 beats/min, and the oxygen saturation was 92.4%±3.9% in these 30 pilots, and it was lower than those before exposure (71.4±10.9 beats/min, 96.3%±1.3%, P<0.05. Compared with the condition before hypoxic exposure, the fALFF value was decreased in superior temporal gyri on both sides and the right superior frontal gyrus, and increase in the left precuneus, while the value of ReHo was decreased in the right superior frontal gyrus (P<0.05. No brain area with an increase in ReHo value was found. Conclusions Hypoxic exposure could significantly affect the brain functions of pilots, which may contribute to change in their cognitive ability. DOI: 10.11855/j.issn.0577-7402.2015.06.18

  19. Protective effect of curcumin on pulmonary and cardiovascular effects induced by repeated exposure to diesel exhaust particles in mice.

    Directory of Open Access Journals (Sweden)

    Abderrahim Nemmar

    Full Text Available Particulate air pollution has been associated with increased risk of cardiopulmonary diseases. However, the underlying mechanisms are not fully understood. We have previously demonstrated that single dose exposure to diesel exhaust particle (DEP causes lung inflammation and peripheral thrombotic events. Here, we exposed mice with repeated doses of DEP (15 µg/animal every 2(nd day for 6 days (a total of 4 exposures, and measured several cardiopulmonary endpoints 48 h after the end of the treatments. Moreover, the potential protective effect of curcumin (the yellow pigment isolated from turmeric on DEP-induced cardiopulmonary toxicity was assessed. DEP exposure increased macrophage and neutrophil numbers, tumor necrosis factor α (TNF α in the bronchoalveolar lavage (BAL fluid, and enhanced airway resistance to methacoline measured invasively using Flexivent. DEP also significantly increased plasma C-reactive protein (CRP and TNF α concentrations, systolic blood pressure (SBP as well as the pial arteriolar thrombosis. It also significantly enhanced the plasma D-dimer and plasminogen activator inhibitor-1 (PAI-1. Pretreatment with curcumin by oral gavage (45 mg/kg 1 h before exposure to DEP significantly prevented the influx of inflammatory cells and the increase of TNF α in BAL, and the increased airway resistance caused by DEP. Likewise, curcumin prevented the increase of SBP, CRP, TNF α, D-dimer and PAI-1. The thrombosis was partially but significantly mitigated. In conclusion, repeated exposure to DEP induced lung and systemic inflammation characterized by TNFα release, increased SBP, and accelerated coagulation. Our findings indicate that curcumin is a potent anti-inflammatory agent that prevents the release of TNFα and protects against the pulmonary and cardiovascular effects of DEP.

  20. Social disparities in children’s exposure to second hand smoke at home: a repeated cross-sectional survey

    Directory of Open Access Journals (Sweden)

    Pisinger Charlotta

    2012-09-01

    Full Text Available Abstract Background Exposure to second hand smoke (SHS is an important preventable cause of morbidity and mortality in children. We hypothesised that there has been a growth in social inequality in children’s exposure to SHS at home over time. The purpose of this study was to investigate temporal change in smoking in homes including children, focusing on the socioeconomic differences. Methods Data is from a repeated cross-sectional survey, ‘Health Profiles of the Capital Region of Denmark’ conducted in 2007 and 2010, in 29 municipalities. The response rate was 52.3%, in both surveys. Our study included persons aged 25 to 64, living with children ≤15 years of age; N=9,289 in 2007 and 12,696 in 2010. Analyses were weighted for size of municipality and for non-response, which was higher among men and among persons who were younger, had a lower income, were living alone, were unemployed, and/or were of an ethnicity other than Danish. Regression analyses were used to investigate smoking in homes including children across parent/adult education levels, focusing on temporal changes. Results There were significant large socioeconomic differences in both 2007 and 2010. In 2010 it was more than 11 times more likely for a child to be exposed to SHS at home if the parent had very low education than if they were highly educated (p Conclusions Marked social inequalities in children’s exposure to SHS and a significant temporal decrease in exposure, independent of the education level of the parent/adult, were found in repeated large cross-sectional population-based studies. Social disparities have persisted over time, but not increased. Both clinical and population policy interventions will be needed in order to control child SHS exposure. We call for legislative protection of children from tobacco smoke inside their home as a supplement to parental education and support for smoking cessation.

  1. Repeated exposure to amphetamine during adolescence alters inhibitory tone in the medial prefrontal cortex following drug re-exposure in adulthood

    Science.gov (United States)

    Cox, Charles L.; Gulley, Joshua M.

    2016-01-01

    Behavioral sensitization following repeated amphetamine (AMPH) exposure is associated with changes in GABA function in the medial prefrontal cortex (mPFC). In rats exposed to AMPH during adolescence compared to adulthood, there are unique patterns of sensitization that may reflect age-dependent differences in drug effects on prefrontal GABAergic function. In the current study, we used a sensitizing regimen of repeated AMPH exposure in adolescent and adult rats to determine if a post-withdrawal AMPH challenge would alter inhibitory transmission in the mPFC in a manner that depends on age of exposure. Male Sprague-Dawley rats were treated with saline or 3 mg/kg AMPH (i.p.) during adolescence [postnatal day (P) 27 to P45] or adulthood (P85 to P103) and were sacrificed either at similar ages in adulthood (~P133; Experiment 1) or after similar withdrawal times (3-4 weeks; Experiment 2). Spontaneous inhibitory postsynaptic currents (sIPSCs) were recorded in vitro from deep layer pyramidal cells in the mPFC using the whole-cell configuration. We found no effect of AMPH pre-exposure on baseline sIPSC frequency. Subsequent application of AMPH (25 μM) produced a stable increase in sIPSC frequency in controls, suggesting that AMPH increases inhibitory tone in the mPFC. However, AMPH failed to increase sIPSCs in adolescent- or adult-exposed rats. In Experiment 2, where withdrawal period was kept similar for both exposure groups, AMPH induced a suppression of sIPSC activity in adolescent-exposed rats. These results suggest that sensitizing treatment with AMPH during adolescence or adulthood dampens inhibitory influences on mPFC pyramidal cells, but potentially through different mechanisms. PMID:27085589

  2. Repeated exposure of the developing rat brain to magnetic resonance imaging did not affect neurogenesis, cell death or memory function

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Changlian [Center for Brain Repair and Rehabilitation, University of Gothenburg (Sweden); Department of Pediatrics, The Third Affiliated Hospital, Zhengzhou University (China); Gao, Jianfeng [Center for Brain Repair and Rehabilitation, University of Gothenburg (Sweden); Department of Pediatrics, The Third Affiliated Hospital, Zhengzhou University (China); Department of Physiology, Henan Traditional Medical University (China); Li, Qian; Huang, Zhiheng; Zhang, Yu; Li, Hongfu [Center for Brain Repair and Rehabilitation, University of Gothenburg (Sweden); Department of Pediatrics, The Third Affiliated Hospital, Zhengzhou University (China); Kuhn, Hans-Georg [Center for Brain Repair and Rehabilitation, University of Gothenburg (Sweden); Blomgren, Klas, E-mail: klas.blomgren@neuro.gu.se [Center for Brain Repair and Rehabilitation, University of Gothenburg (Sweden); Department of Pediatric Oncology, The Queen Silvia Children' s Hospital, Gothenburg (Sweden)

    2011-01-07

    Research highlights: {yields} The effect of MRI on the developing brain is a matter of debate. {yields} Repeated exposure to MRI did not affect neurogenesis. {yields} Memory function was not affected by repeated MRI during development. {yields} Neither late gestation nor young postnatal brains were affected by MRI. {yields} Repeated MRI did not cause cell death in the neurogenic region of the hippocampus. -- Abstract: The effect of magnetic fields on the brain is a matter of debate. The objective of this study was to investigate whether repeated exposure to strong magnetic fields, such as during magnetic resonance imaging (MRI), could elicit changes in the developing rat brain. Embryonic day 15 (E15) and postnatal day 14 (P14) rats were exposed to MRI using a 7.05 T MR system. The animals were anesthetized and exposed for 35 min per day for 4 successive days. Control animals were anesthetized but no MRI was performed. Body temperature was maintained at 37 {sup o}C. BrdU was injected after each session (50 mg/kg). One month later, cell proliferation, neurogenesis and astrogenesis in the dentate gyrus were evaluated, revealing no effects of MRI, neither in the E15, nor in the P14 group. DNA damage in the dentate gyrus in the P14 group was evaluated on P18, 1 day after the last session, using TUNEL staining. There was no difference in the number of TUNEL-positive cells after MRI compared with controls, neither in mature neurons, nor in newborn progenitors (BrdU/TUNEL double-labeled cells). Novel object recognition was performed to assess memory function 1 month after MRI. There was no difference in the recognition index observed after MRI compared with the control rats, neither for the E15, nor for the P14 group. In conclusion, repeated exposure to MRI did not appear to affect neurogenesis, cell death or memory function in rats, neither in late gestation (E15-E18) nor in young postnatal (P14-P17) rats.

  3. Effects of Repeated Ethanol Exposures on NMDA Receptor Expression and Locomotor Sensitization in Mice Expressing Ethanol Resistant NMDA Receptors

    Science.gov (United States)

    den Hartog, Carolina R.; Gilstrap, Meghin; Eaton, Bethany; Lench, Daniel H.; Mulholland, Patrick J.; Homanics, Gregg. E.; Woodward, John J.

    2017-01-01

    Evidence from a large number of preclinical studies suggests that chronic exposure to drugs of abuse, such as psychostimulants or ethanol induces changes in glutamatergic transmission in key brain areas associated with reward and control of behavior. These changes include alterations in the expression of ionotropic glutamate receptors including N-methyl-D-aspartate receptors (NMDAR) that are important for regulating neuronal activity and synaptic plasticity. NMDA receptors are inhibited by ethanol and reductions in NMDA-mediated signaling are thought to trigger homestatic responses that limit ethanol's effects on glutamatergic transmission. Following repeated exposures to ethanol, these homeostatic responses may become unstable leading to an altered glutamatergic state that contributes to the escalations in drinking and cognitive deficits observed in alcohol-dependent subjects. An important unanswered question is whether ethanol-induced changes in NMDAR expression are modulated by the intrinsic sensitivity of the receptor to ethanol. In this study, we examined the effects of ethanol on NMDAR subunit expression in cortical (orbitofrontal, medial prefrontal), striatal (dorsal and ventral striatum) and limbic (dorsal hippocampus, basolateral amygdala) areas in mice genetically modified to express ethanol-resistant receptors (F639A mice). These mice have been previously shown to drink more ethanol than their wild-type counterparts and have altered behavioral responses to certain actions of ethanol. Following long-term voluntary drinking, F639A mice showed elevations in GluN2A but not GluN1 or GluN2B expression as compared to wild-type mice. Mice treated with repeated injections with ethanol (2–3.5 g/kg; i.p.) showed changes in NMDAR expression that varied in a complex manner with genotype, brain region, subunit type and exposure protocol all contributing to the observed response. F639A mice, but not wild-type mice, showed enhanced motor activity following repeated

  4. Distribution of dearomatised white spirit in brain, blood, and fat tissue after repeated exposure of rats

    DEFF Research Database (Denmark)

    Lof, A.; Lam, Henrik Rye; Gullstrand, E.

    1999-01-01

    spirit was 1.5 and 5.6 mg/kg in blood; 7.1 and 17.1 mg/kg in brain; 432 and 1452 mg/kg in fat tissue at the exposure levels of 400 and 800 p.p.m., respectively. The concentrations of n-nonane, n-decane, n-undecane, and total white spirit in blood and brain were not affected by the duration of exposure....... Two hours after the end of exposure the n-decane concentration decreased to about 25% in blood and 50% in brain. A similar pattern of elimination was also observed for n-nonane, n-undecane and total white spirit in blood and brain. In fat tissue the concentrations of n-nonane, n-decane, n......-undecane, and total white spirit increased during the 3 weeks of exposure. The time to reach steady-state concentrations is longer than 3 weeks. After the 3 weeks' exposure the fat tissue concentration of n-nonane, n-decane, n-undecane, and total white spirit decreased very slowly compared with the rate of decrease...

  5. Effects of Repeated Cocaine Exposure on Habit Learning and Reversal by N-Acetylcysteine

    Science.gov (United States)

    Corbit, Laura H; Chieng, Billy C; Balleine, Bernard W

    2014-01-01

    Exposure to drugs of abuse can result in a loss of control over both drug- and nondrug-related actions by accelerating the transition from goal-directed to habitual control, an effect argued to reflect changes in glutamate homeostasis. Here we examined whether exposure to cocaine accelerates habit learning and used in vitro electrophysiology to investigate its effects on measures of synaptic plasticity in the dorsomedial (DMS) and dorsolateral (DLS) striatum, areas critical for actions and habits, respectively. We then administered N-acetylcysteine (NAC) in an attempt to normalize glutamate homeostasis and hence reverse the cellular and behavioral effects of cocaine exposure. Rats received daily injections of cocaine (30 mg/kg) for 6 days and were then trained to lever press for a food reward. We used outcome devaluation and whole-cell patch-clamp electrophysiology to assess the behavioral and cellular effects of cocaine exposure. We then examined the ability of NAC to reverse the effects of cocaine exposure on these measures. Cocaine treatment produced a deficit in goal-directed action, as assessed by outcome devaluation, and increased the frequency of spontaneous and miniature excitatory postsynaptic currents (EPSCs) in the DMS but not in the DLS. Importantly, NAC treatment both normalized EPSC frequency and promoted goal-directed control in cocaine-treated rats. The promotion of goal-directed control has the potential to improve treatment outcomes in human cocaine addicts. PMID:24531561

  6. Metabolite profiles of rats in repeated dose toxicological studies after oral and inhalative exposure.

    Science.gov (United States)

    Fabian, E; Bordag, N; Herold, M; Kamp, H; Krennrich, G; Looser, R; Ma-Hock, L; Mellert, W; Montoya, G; Peter, E; Prokudin, A; Spitzer, M; Strauss, V; Walk, T; Zbranek, R; van Ravenzwaay, B

    2016-07-25

    The MetaMap(®)-Tox database contains plasma-metabolome and toxicity data of rats obtained from oral administration of 550 reference compounds following a standardized adapted OECD 407 protocol. Here, metabolic profiles for aniline (A), chloroform (CL), ethylbenzene (EB), 2-methoxyethanol (ME), N,N-dimethylformamide (DMF) and tetrahydrofurane (THF), dosed inhalatively for six hours/day, five days a week for 4 weeks were compared to oral dosing performed daily for 4 weeks. To investigate if the oral and inhalative metabolome would be comparable statistical analyses were performed. Best correlations for metabolome changes via both routes of exposure were observed for toxicants that induced profound metabolome changes. e.g. CL and ME. Liver and testes were correctly identified as target organs. In contrast, route of exposure dependent differences in metabolic profiles were noted for low profile strength e.g. female rats dosed inhalatively with A or THF. Taken together, the current investigations demonstrate that plasma metabolome changes are generally comparable for systemic effects after oral and inhalation exposure. Differences may result from kinetics and first pass effects. For compounds inducing only weak changes, the differences between both routes of exposure are visible in the metabolome.

  7. Effect of brief, repeated hyperbaric exposures on susceptibility to nitrogen narcosis.

    Science.gov (United States)

    Rogers, W H; Moeller, G

    1989-05-01

    We investigated the effect of brief, repetitive exposures to 5.5 ATA (148 fsw) in a hyperbaric chamber on adaptation to nitrogen narcosis. A standing-steadiness task, which measures body sway, was administered to 2 groups of 3 chamber-qualified men at 5.5 ATA and 1.3 ATA [10 fsw (control)] on each of 12 successive days to determine if an initial performance decrement at 5.5 ATA would be ameliorated with time. Standing steadiness was significantly worse at 5.5 ATA than at 1.3 ATA across all 12 exposures. There were also changes in standing steadiness from day to day, but these changes occurred in both the test and control depths. There was no day-x-depth interaction that would have indicated that the initial performance decrement at 5.5 ATA was reduced with repetitive exposures. These results are taken as evidence that there is little or no behavioral adaptation to nitrogen narcosis in response to brief, repetitive exposures to narcosis-inducing hyperbaric air.

  8. The effect of repeated endurance exercise on IL-6 and sIL-6R and their relationship with sensations of fatigue at rest.

    Science.gov (United States)

    Robson-Ansley, Paula; Barwood, Martin; Canavan, Jane; Hack, Susan; Eglin, Clare; Davey, Sarah; Hewitt, Jennifer; Hull, James; Ansley, Les

    2009-02-01

    Strenuous, prolonged exercise increases interleukin-6 (IL-6) release. The effect of IL-6 is dependent on the availability of IL-6 receptors. Few studies have addressed the impact of exercise on IL-6 receptor levels or procalcitonin (PCT), an indicator of systemic inflammation. Changes in these molecules may give insight into cytokine-related mechanisms underlying exercise-related fatigue. Thirteen trained male subjects partook in the study. They cycled a total distance of 468 km over 6 days. Blood samples were obtained prior to and immediately following Day 1 of the study and then each morning prior to exercise. Blood samples were analysed for plasma IL-6, soluble IL-6 receptor (sIL-6R), C-reactive protein (CRP), PCT, creatine kinase (CK) and cortisol concentrations. Subjects also completed mood state questionnaires each day prior to exercise. IL-6 was elevated immediately post-exercise on Day 1 but was unchanged at rest for the duration of the event. In contrast, sIL-6R, CRP, PCT and CK concentrations were unchanged immediately post-exercise on Day 1 but were significantly elevated at rest over the duration of the event compared with pre-event baseline. sIL-6R was highly correlated to CRP. Cortisol concentrations remained unchanged at all time points. In conclusion, strenuous, prolonged exercise stimulated an acute phase response which was maintained throughout the 6-day event. sIL-6R increase is associated with CRP and may affect subjective sensations of post-exercise fatigue at rest.

  9. Distinctive adaptive response to repeated exposure to hydrogen peroxide associated with upregulation of DNA repair genes and cell cycle arrest

    Directory of Open Access Journals (Sweden)

    Gloria A. Santa-Gonzalez

    2016-10-01

    Full Text Available Many environmental and physiological stresses are chronic. Thus, cells are constantly exposed to diverse types of genotoxic insults that challenge genome stability, including those that induce oxidative DNA damage. However, most in vitro studies that model cellular response to oxidative stressors employ short exposures and/or acute stress models. In this study, we tested the hypothesis that chronic and repeated exposure to a micromolar concentration of hydrogen peroxide (H2O2 could activate DNA damage responses, resulting in cellular adaptations. For this purpose, we developed an in vitro model in which we incubated mouse myoblast cells with a steady concentration of ~50 μM H2O2 for one hour daily for seven days, followed by a final challenge of a 10 or 20X higher dose of H2O2 (0.5 or 1 mM. We report that intermittent long-term exposure to this oxidative stimulus nearly eliminated cell toxicity and significantly decreased genotoxicity (in particular, a >5-fold decreased in double-strand breaks resulting from subsequent acute exposure to oxidative stress. This protection was associated with cell cycle arrest in G2/M and induction of expression of nine DNA repair genes. Together, this evidence supports an adaptive response to chronic, low-level oxidative stress that results in genomic protection and up-regulated maintenance of cellular homeostasis.

  10. The development of behavioral and endocrine abnormalities in rats after repeated exposure to direct and indirect stress.

    Science.gov (United States)

    Daniels, Willie Mark Uren; de Klerk Uys, Joachim; van Vuuren, Petra; Stein, Daniel Joseph

    2008-04-01

    The present study compared the effects of direct and indirect stress on the behavior and hypothalamic-pituitary-adrenal axis of rats. Animals were placed in a two compartment box. In one compartment the direct stressed rat was subjected to electric foot shocks randomly applied for 10 minutes (0.5 mA of 1 s duration). In the adjacent compartment, the indirect stressed rats witnessed the application of these electric foot shocks. Our data showed substantial behavioral changes in the open field test, but limited effects in the elevated plus maze. The findings suggested that single and repeated stress exposure may have different consequences, that the effects of stress exposure may develop over time and persist for an extended period, and that both direct and indirect stressed rats displayed a hyposensitive HPA axis following acute restraint stress. Overall our observations moderately indicate direct exposure to elicit behavioral changes, and both direct and indirect exposure to stress to result in aberrations within the neuroendocrine system. With additional development our stress models may be considered for studying the complex interrelationship between an external stressor, and the experience of the organism.

  11. Single and repeated sevoflurane or desflurane exposure does not impair spatial memory performance of young adult mice.

    Science.gov (United States)

    Kilicaslan, Alper; Belviranli, Muaz; Okudan, Nilsel; Nurullahoglu Atalik, Esra

    2013-12-01

    Volatile anesthetics are known to disturb the spatial memory in aged rodents, but there is insufficient information on their effects on young adult rodents. The aim of this study was to compare the effects of single and repeated exposure to desflurane and sevoflurane on spatial learning and memory functions in young adult mice. Balb/c mice (2 months old) were randomly divided into six equal groups (n = 8). The groups with single inhalation were exposed to 3.3% sevoflurane or 7.8% desflurane or vehicle gas for 4 h, respectively. The groups with repeated inhalation were exposed to 3.3% sevoflurane or 7.8% desflurane or vehicle gas for 2 h a day during 5 consecutive days. Spatial learning and memory were tested in the Morris water maze 24 h after exposure. In the learning phase, the parameters associated with finding the hidden platform and swimming speed, and in the memory phase, time spent in the target quadrant and the adjacent quadrants, were assessed and compared between the groups. In the 4-day learning process, there was no significant difference between the groups in terms of mean latency to platform, mean distance traveled and average speed (P > 0.05). During the memory-test phase, all mice exhibited spatial memory, but there was no significant difference between the groups in terms of time spent in the target quadrant (P > 0.05). Sevoflurane and desflurane anesthesia did not impair acquisition learning and retention memory in young adult mice.

  12. Neonatal Repeated Exposure to Isoflurane not Sevoflurane in Mice Reversibly Impaired Spatial Cognition at Juvenile-Age.

    Science.gov (United States)

    Liu, Jianhui; Zhao, Yanhong; Yang, Junjun; Zhang, Xiaoqing; Zhang, Wei; Wang, Peijun

    2017-02-01

    Inhalation anesthetics facilitate surgical procedures in millions of children each year. However, animal studies demonstrate that exposure to the inhalation anesthetic isoflurane may cause neuronal cell death in developing brains. The long-term cytotoxic effects of sevoflurane, the most popular pediatric anesthetic, have not been compared with isoflurane. Thus, this study was designed to compare the effects of equipotent doses of these two anesthetics on neonatal long-term neurotoxicity. Postnatal 7-day-old (P7) C57/BL male mice were exposed to 1.5% isoflurane or 2.2% sevoflurane 2 h a day for 3 days. Non-anesthetized mice served as controls. The effects of anesthesia on learning and memory were assessed using the Morris Water Maze (MWM) at Postnatal days 30 (P30) and P60 respectively. The hippocampal content of N-methyl-D-aspartate receptor subunits (NMDA), brain-derived neurotrophic factor (BDNF), and synaptophysin (Syn) were determined by Western Blot. Neuron structure and apoptosis were assessed via Nissl and TUNEL staining, respectively. The isoflurane group exhibited cognitive impairment at P30. Repeated inhalation of isoflurane or sevoflurane caused different degrees of apoptosis and damaged hippocampal neurons in neonatal mice, particularly isoflurane. In neonatal mice, repeated exposure to isoflurane, but not sevoflurane, caused spatial cognitive impairments in juvenile mice. Our findings suggest that isoflurane induces significantly greater neurodegeneration than an equipotent minimum alveolar concentration of sevoflurane.

  13. Effects of acute versus repeated cocaine exposure on the expression of endocannabinoid signaling-related proteins in the mouse cerebellum

    Science.gov (United States)

    Palomino, Ana; Pavón, Francisco-Javier; Blanco-Calvo, Eduardo; Serrano, Antonia; Arrabal, Sergio; Rivera, Patricia; Alén, Francisco; Vargas, Antonio; Bilbao, Ainhoa; Rubio, Leticia; Rodríguez de Fonseca, Fernando; Suárez, Juan

    2014-01-01

    Growing awareness of cerebellar involvement in addiction is based on the cerebellum’s intermediary position between motor and reward, potentially acting as an interface between motivational and cognitive functions. Here, we examined the impact of acute and repeated cocaine exposure on the two main signaling systems in the mouse cerebellum: the endocannabinoid (eCB) and glutamate systems. To this end, we investigated whether eCB signaling-related gene and protein expression {cannabinoid receptor type 1 receptors and enzymes that produce [diacylglycerol lipase alpha/beta (DAGLα/β) and N-acyl phosphatidylethanolamine phospholipase D (NAPE-PLD)] and degrade [monoacylglycerol lipase (MAGL) and fatty acid amino hydrolase (FAAH)] eCB} were altered. In addition, we analyzed the gene expression of relevant components of the glutamate signaling system [glutamate synthesizing enzymes liver-type glutaminase isoform (LGA) and kidney-type glutaminase isoform (KGA), metabotropic glutamatergic receptor (mGluR3/5), NMDA-ionotropic glutamatergic receptor (NR1/2A/2B/2C) and AMPA-ionotropic receptor subunits (GluR1/2/3/4)] and the gene expression of tyrosine hydroxylase (TH), the rate-limiting enzyme in catecholamine biosynthesis, because noradrenergic terminals innervate the cerebellar cortex. Results indicated that acute cocaine exposure decreased DAGLα expression, suggesting a down-regulation of 2-arachidonylglycerol (2-AG) production, as well as gene expression of TH, KGA, mGluR3 and all ionotropic receptor subunits analyzed in the cerebellum. The acquisition of conditioned locomotion and sensitization after repeated cocaine exposure were associated with an increased NAPE-PLD/FAAH ratio, suggesting enhanced anandamide production, and a decreased DAGLβ/MAGL ratio, suggesting decreased 2-AG generation. Repeated cocaine also increased LGA gene expression but had no effect on glutamate receptors. These findings indicate that acute cocaine modulates the expression of the eCB and

  14. Whole scalp resting state EEG of oscillatory brain activity shows no parametric relationship with psychoacoustic and psychosocial assessment of tinnitus: A repeated measures study.

    Science.gov (United States)

    Pierzycki, Robert H; McNamara, Adam J; Hoare, Derek J; Hall, Deborah A

    2016-01-01

    Tinnitus is a perception of sound that can occur in the absence of an external stimulus. A brief review of electroencephalography (EEG) and magnetoencephalography (MEG) literature demonstrates that there is no clear relationship between tinnitus presence and frequency band power in whole scalp or source oscillatory activity. Yet a preconception persists that such a relationship exists and that resting state EEG could be utilised as an outcome measure for clinical trials of tinnitus interventions, e.g. as a neurophysiological marker of therapeutic benefit. To address this issue, we first examined the test-retest correlation of EEG band power measures in tinnitus patients (n = 42). Second we examined the evidence for a parametric relationship between numerous commonly used tinnitus variables (psychoacoustic and psychosocial) and whole scalp EEG power spectra, directly and after applying factor reduction techniques. Test-retest correlation for both EEG band power measures and tinnitus variables were high. Yet we found no relationship between whole scalp EEG band powers and psychoacoustic or psychosocial variables. We conclude from these data that resting state whole scalp EEG should not be used as a biomarker for tinnitus and that greater caution should be exercised in regard to reporting of findings to avoid confirmation bias. The data was collected during a randomised controlled trial registered at ClinicalTrials.gov (Identifier: NCT01541969).

  15. Effects of repeated exposure of diazinon on cholinesterase activity and growth in snakehead fish (Channa striata).

    Science.gov (United States)

    Cong, Nguyen Van; Phuong, Nguyen Thanh; Bayley, Mark

    2009-03-01

    The organophosphate insecticide diazinon is widely used in the Mekong river delta and often applied several times per rice crop. In the present study, juvenile snakehead fish Channa striata, which is a commercially important inhabitant of rice fields, were exposed twice to 4-day pulses of 0.016, 0.079 or 0.35mg/L of diazinon, separated by a 2 week interval to imitate the exposure conditions in the field. After the 4-day exposures to these environmentally realistic concentrations, the fish were moved to clean water for recovery. During this experiment, which lasted a total of 2 months, the individual growth rates and brain cholinesterase levels were measured. We show not only that diazinon caused long term inhibition of brain ChE activity, which was still significantly depressed at the termination of the experiment, but also that the highest of these realistic concentrations caused a significant 30% growth inhibition.

  16. Writing content predicts benefit from written expressive disclosure: Evidence for repeated exposure and self-affirmation.

    Science.gov (United States)

    Niles, Andrea N; Byrne Haltom, Kate E; Lieberman, Matthew D; Hur, Christopher; Stanton, Annette L

    2016-01-01

    Expressive disclosure regarding a stressful event improves psychological and physical health, yet predictors of these effects are not well established. The current study assessed exposure, narrative structure, affect word use, self-affirmation and discovery of meaning as predictors of anxiety, depressive and physical symptoms following expressive writing. Participants (N = 50) wrote on four occasions about a stressful event and completed self-report measures before writing and three months later. Essays were coded for stressor exposure (level of detail and whether participants remained on topic), narrative structure, self-affirmation and discovery of meaning. Linguistic Inquiry and Word Count software was used to quantify positive and negative affect word use. Controlling for baseline anxiety, more self-affirmation and detail about the event predicted lower anxiety symptoms, and more negative affect words (very high use) and more discovery of meaning predicted higher anxiety symptoms three months after writing. Findings highlight the importance of self-affirmation and exposure as predictors of benefit from expressive writing.

  17. Effects of chronic dietary selenomethionine exposure on repeat swimming performance, aerobic metabolism and methionine catabolism in adult zebrafish (Danio rerio).

    Science.gov (United States)

    Thomas, Jith K; Wiseman, Steve; Giesy, John P; Janz, David M

    2013-04-15

    In a previous study we reported impaired swimming performance and greater stored energy in adult zebrafish (Danio rerio) after chronic dietary exposure to selenomethionine (SeMet). The goal of the present study was to further investigate effects of chronic exposure to dietary SeMet on repeat swimming performance, oxygen consumption (MO2), metabolic capacities (standard metabolic rate [SMR], active metabolic rate [AMR], factorial aerobic scope [F-AS] and cost of transport [COT]) and gene expression of energy metabolism and methionine catabolism enzymes in adult zebrafish. Fish were fed SeMet at measured concentrations of 1.3, 3.4, 9.8 or 27.5 μg Se/g dry mass (d.m.) for 90 d. At the end of the exposure period, fish from each treatment group were divided into three subgroups: (a) no swim, (b) swim, and (c) repeat swim. Fish from the no swim group were euthanized immediately at 90 d and whole body triglycerides, glycogen and lactate, and gene expression of energy metabolism and methionine catabolism enzymes were determined. Individual fish from the swim group were placed in a swim tunnel respirometer and swimming performance was assessed by determining the critical swimming speed (U(crit)). After both Ucrit and MO2 analyses, fish were euthanized and whole body energy stores and lactate were determined. Similarly, individual fish from the repeat swim group were subjected to two U(crit) tests (U(crit-1) and U(crit-2)) performed with a 60 min recovery period between tests, followed by determination of energy stores and lactate. Impaired swim performance was observed in fish fed SeMet at concentrations greater than 3 μg Se/g in the diet. However, within each dietary Se treatment group, no significant differences between single and repeat U(crits) were observed. Oxygen consumption, SMR and COT were significantly greater, and F-AS was significantly lesser, in fish fed SeMet. Whole body triglycerides were proportional to the concentration of SeMet in the diet. While

  18. Repeated exposure to neurotoxic levels of chlorpyrifos alters hippocampal expression of neurotrophins and neuropeptides.

    Science.gov (United States)

    Lee, Young S; Lewis, John A; Ippolito, Danielle L; Hussainzada, Naissan; Lein, Pamela J; Jackson, David A; Stallings, Jonathan D

    2016-01-18

    Chlorpyrifos (CPF), an organophosphorus pesticide (OP), is one of the most widely used pesticides in the world. Subchronic exposures to CPF that do not cause cholinergic crisis are associated with problems in cognitive function (i.e., learning and memory deficits), but the biological mechanism(s) underlying this association remain speculative. To identify potential mechanisms of subchronic CPF neurotoxicity, adult male Long Evans (LE) rats were administered CPF at 3 or 10mg/kg/d (s.c.) for 21 days. We quantified mRNA and non-coding RNA (ncRNA) expression profiles by RNA-seq, microarray analysis and small ncRNA sequencing technology in the CA1 region of the hippocampus. Hippocampal slice immunohistochemistry was used to determine CPF-induced changes in protein expression and localization patterns. Neither dose of CPF caused overt clinical signs of cholinergic toxicity, although after 21 days of exposure, cholinesterase activity was decreased to 58% or 13% of control levels in the hippocampus of rats in the 3 or 10mg/kg/d groups, respectively. Differential gene expression in the CA1 region of the hippocampus was observed only in the 10mg/kg/d dose group relative to controls. Of the 1382 differentially expressed genes identified by RNA-seq and microarray analysis, 67 were common to both approaches. Differential expression of six of these genes (Bdnf, Cort, Crhbp, Nptx2, Npy and Pnoc) was verified in an independent CPF exposure study; immunohistochemistry demonstrated that CRHBP and NPY were elevated in the CA1 region of the hippocampus at 10mg/kg/d CPF. Gene ontology enrichment analysis suggested association of these genes with receptor-mediated cell survival signaling pathways. miR132/212 was also elevated in the CA1 hippocampal region, which may play a role in the disruption of neurotrophin-mediated cognitive processes after CPF administration. These findings identify potential mediators of CPF-induced neurobehavioral deficits following subchronic exposure to CPF at

  19. Hyperalgesic priming (type II) induced by repeated opioid exposure: maintenance mechanisms.

    Science.gov (United States)

    Araldi, Dioneia; Ferrari, Luiz F; Levine, Jon D

    2017-07-01

    We previously developed a model of opioid-induced neuroplasticity in the peripheral terminal of the nociceptor that could contribute to opioid-induced hyperalgesia, type II hyperalgesic priming. Repeated administration of mu-opioid receptor (MOR) agonists, such as DAMGO, at the peripheral terminal of the nociceptor, induces long-lasting plasticity expressed, prototypically as opioid-induced hyperalgesia and prolongation of prostaglandin E2-induced hyperalgesia. In this study, we evaluated the mechanisms involved in the maintenance of type II priming. Opioid receptor antagonist, naloxone, induced hyperalgesia in DAMGO-primed paws. When repeatedly injected, naloxone-induced hyperalgesia, and hyperalgesic priming, supporting the suggestion that maintenance of priming involves changes in MOR signaling. However, the knockdown of MOR with oligodeoxynucleotide antisense did not reverse priming. Mitogen-activated protein kinase and focal adhesion kinase, which are involved in the Src signaling pathway, previously implicated in type II priming, also inhibited the expression, but not maintenance of priming. However, when Src and mitogen-activated protein kinase inhibitors were coadministered, type II priming was reversed, in male rats. A second model of priming, latent sensitization, induced by complete Freund's adjuvant was also reversed, in males. In females, the inhibitor combination was only able to inhibit the expression and maintenance of DAMGO-induced priming when knockdown of G-protein-coupled estrogen receptor 30 (GPR30) in the nociceptor was performed. These findings demonstrate that the maintenance of DAMGO-induced type II priming, and latent sensitization is mediated by an interaction between, Src and MAP kinases, which in females is GPR30 dependent.

  20. Neurobehavioral toxicity of a repeated exposure (14 days to the airborne polycyclic aromatic hydrocarbon fluorene in adult Wistar male rats.

    Directory of Open Access Journals (Sweden)

    Julie Peiffer

    Full Text Available Fluorene is one of the most abundant polycyclic aromatic hydrocarbons in air and may contribute to the neurobehavioral alterations induced by the environmental exposure of humans to PAHs. Since no data are available on fluorene neurotoxicity, this study was conducted in adult rats to assess the behavioral toxicity of repeated fluorene inhalation exposure. Male rats (n = 18/group were exposed nose-only to 1.5 or 150 ppb of fluorene 6 hours/day for 14 consecutive days, whereas the control animals were exposed to non-contaminated air. At the end of the exposure, animals were tested for activity and anxiety in an open-field and in an elevated-plus maze, for short-term memory in a Y-maze, and for spatial learning in an eight-arm maze. The results showed that the locomotor activity and the learning performances of the animals were unaffected by fluorene. In parallel, the fluorene-exposed rats showed a lower level of anxiety than controls in the open-field, but not in the elevated-plus maze, which is probably due to a possible difference in the aversive feature of the two mazes. In the same animals, increasing blood and brain levels of fluorene monohydroxylated metabolites (especially the 2-OH fluorene were detected at both concentrations (1.5 and 150 ppb, demonstrating the exposure of the animals to the pollutant and showing the ability of this compound to be metabolized and to reach the cerebral compartment. The present study highlights the possibility for a 14-day fluorene exposure to induce some specific anxiety-related behavioral disturbances, and argues in favor of the susceptibility of the adult brain when exposed to volatile fluorene.

  1. Effects of heat exposure and 3% dehydration achieved via hot water immersion on repeated cycle sprint performance.

    Science.gov (United States)

    Kraft, Justin A; Green, James M; Bishop, Phillip A; Richardson, Mark T; Neggers, Yasmin H; Leeper, James D

    2011-03-01

    This study examined effects of heat exposure with and without dehydration on repeated anaerobic cycling. Males (n = 10) completed 3 trials: control (CT), water-bath heat exposure (∼39°C) to 3% dehydration (with fluid replacement) (HE), and similar heat exposure to 3% dehydration (DEHY). Hematocrit increased significantly from pre to postheat immersion in both HE and DEHY. Participants performed 6 × 15s cycle sprints (30s active recovery). Mean Power (MP) was significantly lower vs. CT (596 ± 66 W) for DEHY (569 ± 72 W), and the difference approached significance for HE (582 ± 76 W, p = 0.07). Peak Power (PP) was significantly lower vs. CT (900 ± 117 W) for HE (870 ± 128 W) and approached significance for DEHY (857 ± 145 W, p = 0.07). Postsprint ratings of perceived exertion was higher during DEHY (6.4 ± 2.0) and HE (6.3 ± 1.6) than CT (5.7 ± 2.1). Combined heat and dehydration impaired MP and PP (decrements greatest in later bouts) with HE performance intermediate to CT and DEHY.

  2. Motion sickness severity and physiological correlates during repeated exposures to a rotating optokinetic drum

    Science.gov (United States)

    Hu, Senqi; Grant, Wanda F.; Stern, Robert M.; Koch, Kenneth L.

    1991-01-01

    Fifty-two subjects were exposed to a rotating optokinetic drum. Ten of these subjects who became motion sick during the first session completed two additional sessions. Subjects' symptoms of motion sickness, perception of self-motion, electrogastrograms (EGGs), heart rate, mean successive differences of R-R intervals (RRI), and skin conductance were recorded for each session. The results from the first session indicated that the development of motion sickness was accompanied by increased EGG 4-9 cpm activity (gastric tachyarrhythmia), decreased mean succesive differences of RRI, increased skin conductance levels, and increased self-motion perception. The results from the subjects who had three repeated sessions showed that 4-9 cpm EGG activity, skin conductance levels, perception of self-motion, and symptoms of motion sickness all increased significantly during the drum rotation period of the first session, but increased significantly less during the following sessions. Mean successive differences of RRI decreased significantly during the drum rotation period for the first session, but decreased significantly less during the following sessions. Results show that the development of motion sickness is accompanied by an increase in gastric tachyarrhythmia, and an increase in sympathetic activity and a decrease in parasympathetic activity, and that adaptation to motion sickness is accompanied by the recovery of autonomic nervous system balance.

  3. Long-Term Evolution Electromagnetic Fields Exposure Modulates the Resting State EEG on Alpha and Beta Bands.

    Science.gov (United States)

    Yang, Lei; Chen, Qinghua; Lv, Bin; Wu, Tongning

    2016-04-25

    Long-term evolution (LTE) wireless telecommunication systems are widely used globally, which has raised a concern that exposure to electromagnetic fields (EMF) emitted from LTE devices can change human neural function. To date, few studies have been conducted on the effect of exposure to LTE EMF. Here, we evaluated the changes in electroencephalogram (EEG) due to LTE EMF exposure. An LTE EMF exposure system with a stable power emission, which was equivalent to the maximum emission from an LTE mobile phone, was used to radiate the subjects. Numerical simulations were conducted to ensure that the specific absorption rate in the subject's head was below the safety limits. Exposure to LTE EMF reduced the spectral power and the interhemispheric coherence in the alpha and beta bands of the frontal and temporal brain regions. No significant change was observed in the spectral power and the inter-hemispheric coherence in different timeslots during and after the exposure. These findings also corroborated those of our previous study using functional magnetic resonant imaging.

  4. Heart rate variability and DNA methylation levels are altered after short-term metal fume exposure among occupational welders: a repeated-measures panel study

    OpenAIRE

    2014-01-01

    Background: In occupational settings, boilermakers are exposed to high levels of metallic fine particulate matter (PM2.5) generated during the welding process. The effect of welding PM2.5 on heart rate variability (HRV) has been described, but the relationship between PM2.5, DNA methylation, and HRV is not known. Methods: In this repeated-measures panel study, we recorded resting HRV and measured DNA methylation levels in transposable elements Alu and long interspersed nuclear element-1 (LINE...

  5. Tualang Honey Protects the Rat Midbrain and Lung against Repeated Paraquat Exposure

    Science.gov (United States)

    Sulaiman, Siti Amrah

    2017-01-01

    Paraquat (PQ) is a dopaminergic neurotoxin and a well-known pneumotoxicant that exerts its toxic effect via oxidative stress-mediated cellular injuries. This study investigated the protective effects of Tualang honey against PQ-induced toxicity in the midbrain and lungs of rats. The rats were orally treated with distilled water (2 mL/kg/day), Tualang honey (1.0 g/kg/day), or ubiquinol (0.2 g/kg/day) throughout the experimental period. Two weeks after the respective treatments, the rats were injected intraperitoneally with saline (1 mL/kg/week) or PQ (10 mg/kg/week) once per week for four consecutive weeks. After four weekly exposures to PQ, the glutathione peroxidase activity and the number of tyrosine-hydroxylase immunopositive neurons in the midbrain were significantly decreased in animals from group PQ (p < 0.05). The lungs of animals from group PQ showed significantly decreased activity of superoxide dismutase and glutathione-S-transferase. Treatment with Tualang honey ameliorated the toxic effects observed in the midbrain and lungs. The beneficial effects of Tualang honey were comparable to those of ubiquinol, which was used as a positive control. These findings suggest that treatment with Tualang honey may protect against PQ-induced toxicity in the rat midbrain and lung. PMID:28127418

  6. Tualang Honey Protects the Rat Midbrain and Lung against Repeated Paraquat Exposure

    Directory of Open Access Journals (Sweden)

    Suk Peng Tang

    2017-01-01

    Full Text Available Paraquat (PQ is a dopaminergic neurotoxin and a well-known pneumotoxicant that exerts its toxic effect via oxidative stress-mediated cellular injuries. This study investigated the protective effects of Tualang honey against PQ-induced toxicity in the midbrain and lungs of rats. The rats were orally treated with distilled water (2 mL/kg/day, Tualang honey (1.0 g/kg/day, or ubiquinol (0.2 g/kg/day throughout the experimental period. Two weeks after the respective treatments, the rats were injected intraperitoneally with saline (1 mL/kg/week or PQ (10 mg/kg/week once per week for four consecutive weeks. After four weekly exposures to PQ, the glutathione peroxidase activity and the number of tyrosine-hydroxylase immunopositive neurons in the midbrain were significantly decreased in animals from group PQ (p<0.05. The lungs of animals from group PQ showed significantly decreased activity of superoxide dismutase and glutathione-S-transferase. Treatment with Tualang honey ameliorated the toxic effects observed in the midbrain and lungs. The beneficial effects of Tualang honey were comparable to those of ubiquinol, which was used as a positive control. These findings suggest that treatment with Tualang honey may protect against PQ-induced toxicity in the rat midbrain and lung.

  7. Neuronal changes and oxidative stress in adolescent rats after repeated exposure to mephedrone

    Energy Technology Data Exchange (ETDEWEB)

    López-Arnau, Raúl; Martínez-Clemente, José [Department of Pharmacology and Therapeutic Chemistry (Pharmacology Section), Faculty of Pharmacy, University of Barcelona (Spain); Institute of Biomedicine (IBUB), Faculty of Pharmacy, University of Barcelona (Spain); Rodrigo, Teresa [Animal Experimentation Unit of Psychology and Pharmacy, University of Barcelona (Spain); Pubill, David [Department of Pharmacology and Therapeutic Chemistry (Pharmacology Section), Faculty of Pharmacy, University of Barcelona (Spain); Institute of Biomedicine (IBUB), Faculty of Pharmacy, University of Barcelona (Spain); Camarasa, Jorge, E-mail: jcamarasa@ub.edu [Department of Pharmacology and Therapeutic Chemistry (Pharmacology Section), Faculty of Pharmacy, University of Barcelona (Spain); Institute of Biomedicine (IBUB), Faculty of Pharmacy, University of Barcelona (Spain); Escubedo, Elena [Department of Pharmacology and Therapeutic Chemistry (Pharmacology Section), Faculty of Pharmacy, University of Barcelona (Spain); Institute of Biomedicine (IBUB), Faculty of Pharmacy, University of Barcelona (Spain)

    2015-07-01

    Mephedrone is a new designer drug of abuse. We have investigated the neurochemical/enzymatic changes after mephedrone administration to adolescent rats (3 × 25 mg/kg, s.c. in a day, with a 2 h interval between doses, for two days) at high ambient temperature (26 ± 2 °C), a schedule that intends to model human recreational abuse. In addition, we have studied the effect of mephedrone in spatial learning and memory. The drug caused a transient decrease in weight gain. After the first dose, animals showed hypothermia but, after the subsequent doses, temperature raised over the values of saline-treated group. We observed the development of tolerance to these thermoregulatory effects of mephedrone. Mephedrone induced a reduction of the densities of dopamine (30% in the frontal cortex) and serotonin (40% in the frontal cortex and the hippocampus and 48% in the striatum) transporters without microgliosis. These deficits were also accompanied by a parallel decrease in the expression of tyrosine hydroxylase and tryptophan hydroxylase 2. These changes matched with a down-regulation of D{sub 2} dopamine receptors in the striatum. Mephedrone also induced an oxidative stress evidenced by an increase of lipid peroxidation in the frontal cortex, and accompanied by a rise in glutathione peroxidase levels in all studied brain areas. Drug-treated animals displayed an impairment of the reference memory in the Morris water maze one week beyond the cessation of drug exposure, while the spatial learning process seems to be preserved. These findings raise concerns about the neuronal long-term effects of mephedrone. - Highlights: • We studied the dopaminergic and serotonergic neurotoxicity of mephedrone in rats. • Mephedrone induced a transient hypothermia following sustained hyperthermia. • In a weekend consumption pattern, mephedrone induced selective neurotoxicity. • Mephedrone generated oxidative stress. • Mephedrone induced an impairment in memory function.

  8. Effects of repeated exposure to 4-nonylphenol on the zooplankton community in littoral enclosures

    Energy Technology Data Exchange (ETDEWEB)

    O`Halloran, S.L.; Liber, K.; Gangl, J.A. [Univ. of Wisconsin, Superior, WI (United States). Lake Superior Research Inst.; Knuth, M.L. [Environmental Protection Agency, Duluth, MN (United States). Mid-Continent Ecology Div.

    1999-03-01

    The effects of 4-nonylphenol (NP) on freshwater zooplankton were evaluated in 18 littoral enclosure mesocosms in northeastern Minnesota. The 18 enclosures were allocated to three blocks of six units with each block including two untreated control enclosures and one enclosure for each of four NP treatments. Treated enclosures received 11 applications of NP over a 20-d period between July 8 and 28, 1993. Maximum NP concentrations measured in the water column 2 h after each application averaged ({+-} SD) 5 {+-} 4, 23 {+-} 11, 76 {+-} 21, and 243 {+-} 41 {micro}g/L over the 11 applications. Nonylphenol dissipated rapidly from the water column but was more persistent in sediments and in/on macrophytes. All cladoceran and copepod taxa were significantly reduced in abundance at 243 {+-} 41 {micro}g/L; some sensitive taxa were also affected by 76 {+-} 21 and 23 {+-} 11 {micro}g/L. While many rotifer taxa were unaffected at any of the test concentrations, several were affected at {ge} 76 {+-} 21 {micro}g/L. Ostracods were only affected at 2,243 {+-} 41 {micro}g/L. No zooplankton taxon was affected at 5 {+-} 4 {micro}g/L. The period of maximum impact usually occurred within 1 to 7 d of the last NP application, and recovery to control abundance levels generally occurred within 7 to 28 d of the last NP application. Two sensitive taxa, Acroperus and Calanoida, did not recover at {ge} 76 {+-} 21 {micro}g/L by the end of the study. The maximum acceptable toxicant concentration for protection of all zooplankton taxa was estimated at {approximately} 10 {micro}g/L, although overall community diversity was unaffected at 23 {+-} 11. The water was the most probable route of NP exposure, but the greater persistence of NP residues in/on macrophytes may have contributed to the lack of recovery of some macrophyte-associated taxa.

  9. Neuronal changes and oxidative stress in adolescent rats after repeated exposure to mephedrone.

    Science.gov (United States)

    López-Arnau, Raúl; Martínez-Clemente, José; Rodrigo, Teresa; Pubill, David; Camarasa, Jorge; Escubedo, Elena

    2015-07-01

    Mephedrone is a new designer drug of abuse. We have investigated the neurochemical/enzymatic changes after mephedrone administration to adolescent rats (3×25 mg/kg, s.c. in a day, with a 2 h interval between doses, for two days) at high ambient temperature (26±2 °C), a schedule that intends to model human recreational abuse. In addition, we have studied the effect of mephedrone in spatial learning and memory. The drug caused a transient decrease in weight gain. After the first dose, animals showed hypothermia but, after the subsequent doses, temperature raised over the values of saline-treated group. We observed the development of tolerance to these thermoregulatory effects of mephedrone. Mephedrone induced a reduction of the densities of dopamine (30% in the frontal cortex) and serotonin (40% in the frontal cortex and the hippocampus and 48% in the striatum) transporters without microgliosis. These deficits were also accompanied by a parallel decrease in the expression of tyrosine hydroxylase and tryptophan hydroxylase 2. These changes matched with a down-regulation of D2 dopamine receptors in the striatum. Mephedrone also induced an oxidative stress evidenced by an increase of lipid peroxidation in the frontal cortex, and accompanied by a rise in glutathione peroxidase levels in all studied brain areas. Drug-treated animals displayed an impairment of the reference memory in the Morris water maze one week beyond the cessation of drug exposure, while the spatial learning process seems to be preserved. These findings raise concerns about the neuronal long-term effects of mephedrone.

  10. Responses of soil ammonia-oxidizing microorganisms to repeated exposure of single-walled and multi-walled carbon nanotubes.

    Science.gov (United States)

    Chen, Qinglin; Wang, Hui; Yang, Baoshan; He, Fei; Han, Xuemei; Song, Ziheng

    2015-02-01

    The impacts of carbon nanotubes (CNTs) including single-walled carbon nanotubes (SWNTs) and multi-walled carbon nanotubes (MWNTs) on soil microbial biomass and microbial community composition (especially on ammonium oxidizing microorganisms) have been evaluated. The first exposure of CNTs lowered the microbial biomass immediately, but the values recovered to the level of the control at the end of the experiment despite the repeated addition of CNTs. The abundance and diversity of ammonium-oxidizing archaea (AOA) were higher than that of ammonium-oxidizing bacteria (AOB) under the exposure of CNTs. The addition of CNTs decreased Shannon-Wiener diversity index of AOB and AOA. Two-way ANOVA analysis showed that CNTs had significant effects on the abundance and diversity of AOB and AOA. Dominant terminal restriction fragments (TRFs) of AOB exhibited a positive relationship with NH4(+), while AOA was on the contrary. It implied that AOB prefer for high-NH4(+) soils whereas AOA is favored in low NH4(+) soils in the CNT-contaminated soil. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. The sensory response to capsaicin during repeated topical exposures: differential effects on sensations of itching and pungency.

    Science.gov (United States)

    Green, B G; Shaffer, G S

    1993-06-01

    Changes in sensory irritation were measured during repeated topical exposures to capsaicin over 2 days. The perceived intensities of itching and pungent sensations, predominantly burning and stinging/pricking, were assessed every 60 sec during 5 applications of capsaicin at inter-stimulus intervals (ISI) of 90 min (Exp. 1) or 15 min (Exp. 2) and in follow-up tests 24 h later. Psychophysical measurements were obtained with a hand-held dynamometer in conjunction with the method of magnitude production. When the ISI was 90 min, itching and pungency were both significantly reduced (i.e., desensitization occurred) by the fifth exposure; however, the reduction occurred more rapidly and dramatically for itching. After 24 h, desensitization remained significant only for itching. When the ISI was 15 min, the sensations on day 1 first intensified in a manner consistent with sensitization, then declined in a manner consistent with desensitization; compared to pungency, itch exhibited less sensitization and more desensitization. On day 2, overall intensity was less for both categories of sensation, primarily because of a reduction in sensitization. Marked individual differences were observed in the overall sensitivity to capsaicin, the time course of sensation, the susceptibility to capsaicin-induced itch, and the rate and duration of sensitization and desensitization. The results are discussed in terms of current hypotheses about the sensory mechanisms that underlie chemically induced itch and the use of capsaicin as a topical analgesic and antipruritic.

  12. A Study for the Characteristic Changes Under the Repeated Thermal Exposure in the Process of Repairing Aircraft Sandwich Structures

    Science.gov (United States)

    Kim, Yun Hae; Han, Joong Won; Kim, Don Won; Choi, Byung Keun; Murakami, R.

    Delamination can be observed in the sound areas during and/or after a couple times exposure to the elevated curing temperature due to the repeated repair condition. This study was conducted for checking the degree of degradation of properties of the cured parts and delamination between skin prepreg and honeycomb core. Specimens with glass honeycomb sandwich construction and glass/epoxy prepreg were prepared. The specimens were cured 1 to 5 times at 260°F in an autoclave and each additionally exposed 50, 100 and 150 hours in the 260°F oven. Each specimen was tested for tensile strength, compressive strength, flatwise tensile strength and interlaminar shear strength. To monitor the characteristics of the resin itself, the cured resin was tested using DMA and DSC. As a results, the decrease of Tg value were observed in the specific specimen which is exposed over 50 hrs at 260°F. This means the change or degradative of resin properties is also related to the decrease of flatwise tensile properties. Accordingly, minimal exposure on the curing temperature is recommended for parts in order to prevent the delation and maintain the better condition.

  13. RESTful NET

    CERN Document Server

    Flanders, Jon

    2008-01-01

    RESTful .NET is the first book that teaches Windows developers to build RESTful web services using the latest Microsoft tools. Written by Windows Communication Foundation (WFC) expert Jon Flanders, this hands-on tutorial demonstrates how you can use WCF and other components of the .NET 3.5 Framework to build, deploy and use REST-based web services in a variety of application scenarios. RESTful architecture offers a simpler approach to building web services than SOAP, SOA, and the cumbersome WS- stack. And WCF has proven to be a flexible technology for building distributed systems not necessa

  14. Repeated Cycles of Chronic Intermittent Ethanol Exposure Increases Basal Glutamate in the Nucleus Accumbens of Mice without affecting glutamate transport

    Directory of Open Access Journals (Sweden)

    William C. Griffin

    2015-02-01

    Full Text Available Repeated cycles of chronic intermittent ethanol (CIE exposure increase voluntary consumption of ethanol in mice. Previous work has shown that extracellular glutamate in the nucleus accumbens (NAc is significantly elevated in ethanol dependent mice and that pharmacologically manipulating glutamate concentrations in the NAc will alter ethanol drinking, indicating that glutamate homeostasis plays a crucial role in ethanol drinking in this model. The present studies were designed to measure extracellular glutamate at a time point in which mice would ordinarily be allowed voluntary access to ethanol in the CIE model and, additionally, to measure glutamate transport capacity in the NAc at the same time point. Extracellular glutamate was measured using quantitative microdialysis procedures. Glutamate transport capacity was measured under Na+ dependent and Na+ independent conditions to determine whether the function of excitatory amino acid transporters (EAATs; also known as system XAG or of system Xc- (Glial cysteine-glutamate exchanger was influenced by CIE exposure. The results of the quantitative microdialysis experiment confirm increased extracellular glutamate (~2 –fold in the NAc of CIE exposed mice (i.e. ethanol-dependent compared to non-dependent mice in the NAc, consistent with earlier work. However, the increase in extracellular glutamate was not due to altered transporter function in the NAc of ethanol-dependent mice, because neither Na+ dependent nor Na+ independent glutamate transport was significantly altered by CIE exposure. These findings point to the possibility that hyperexcitability of cortical-striatal pathways underlies the increases in extracellular glutamate found in the nucleus accumbens of ethanol-dependent mice.

  15. Effect of repeated nicotine exposure on high-affinity nicotinic acetylcholine receptor density in spontaneously hypertensive rats.

    Science.gov (United States)

    Hohnadel, Elizabeth J; Hernandez, Caterina M; Gearhart, Debra A; Terry, Alvin V

    Spontaneously hypertensive rats (SHRs) are often used as a model of attention deficit hyperactivity disorder (ADHD) and to investigate the effects of hypertension on cognitive function. Further, they appear to have reduced numbers of central nicotinic acetylcholine receptors (nAChRs) and, therefore, may be useful to model certain aspects of Alzheimer's disease (AD) and other forms of dementia given that a decrease in nAChRs is thought to contribute to cognitive decline in these disorders. In the present study, based on reports that chronic nicotine exposure increases nAChRs in several mammalian models, we tested the hypothesis that repeated exposures to a relatively low dose of the alkaloid would ameliorate the receptor deficits in SHR. Thus, young-adult SHRs and age-matched Wistar-Kyoto (WKY) control rats were treated with either saline or nicotine twice a day for 14 days (total daily dose = 0.7 mg/kg nicotine base) and then sacrificed. Quantitative receptor autoradiography with [125I]-IPH, an epibatidine analog, revealed: (1) that high-affinity nAChRs were higher in saline-treated WKY (control) rats compared to saline-treated SHRs in 18 of the 19 brain region measured, although statistically different only in the mediodorsal thalamic nuclei, (2) that nicotine significantly increased nAChR binding in WKY rats in six brain areas including cortical regions and the anterior thalamic nucleus, (3) that there were no cases where nicotine significantly increased nAChR binding in SHRs. These results indicate that subjects deficient in nAChRs may be less sensitive to nAChR upregulation with nicotine than normal subjects and require higher doses or longer periods of exposure.

  16. Adaptation of the pituitary-adrenal axis to daily repeated forced swim exposure in rats is dependent on the temperature of water.

    Science.gov (United States)

    Rabasa, Cristina; Delgado-Morales, Raúl; Gómez-Román, Almudena; Nadal, Roser; Armario, Antonio

    2013-11-01

    Comparison of exposure to certain predominantly emotional stressors reveals a qualitatively similar neuroendocrine response profile as well as a reduction of physiological responses after daily repeated exposure (adaptation). However, particular physical components of the stressor may interfere with adaptation. As defective adaptation to stress can enhance the probability to develop pathologies, we studied in adult male rats (n = 10/group) swimming behavior (struggling, immobility and mild swim) and physiological responses (ACTH, corticosterone and rectal temperature) to daily repeated exposure to forced swim (20 min, 13 d) at 25 or 36 °C (swim25 or swim36). Rats were repeatedly blood-sampled by tail-nick and hormones measured by radioimmunoassay. Some differences were observed between the two swim temperature groups after the first exposure to forced swim: (a) active behaviors were greater in swim25 than swim36 groups; (b) swim25 but not swim36 caused hypothermia; and (c) swim36 elicited the same ACTH response as swim25, but plasma corticosterone concentration was lower for swim36 at 30 min post-swim. After daily repeated exposure, adaptation in ACTH secretion was observed with swim36 already on day 4, whereas with swim25 adaptation was not observed until day 13 and was of lower magnitude. Nevertheless, after repeated exposure to swim25 a partial protection from hypothermia was observed and the two swim conditions resulted in progressive reduction of active behaviors. Thus, daily repeated swim at 25 °C impairs adaptation of the hypothalamic-pituitary-adrenal axis as compared to swim at 36 °C, supporting the hypothesis that certain physical components of predominantly emotional stressors can interfere with the process of adaptation.

  17. Quantification of print, radio and television exposure among previous blood donors in Kenya: an opportunity for encouraging repeat donation in a resource-limited setting?

    Science.gov (United States)

    Basavaraju, S V; Mwangi, J; Kellogg, T A; Odawo, L; Marum, L H

    2010-10-01

    Blood services in sub-Saharan Africa experience blood shortages and low retention of voluntary, non-remunerated donors. To boost collections by encouraging repeat donations, the Kenya National Blood Transfusion Service is exploring the likelihood of reaching previous donors through targeted print, radio and television advertising. We analysed data from a national AIDS Indicator Survey to determine whether previous donors have significant exposure to media. Respondents reporting history of blood donation had significantly higher exposure to print, radio and television media than those without history of blood donation. Targeted media campaigns encouraging repeat donation are likely to reach previous donors even in resource-limited settings.

  18. Effect of replacing sugar with non-caloric sweeteners in beverages on the reward value after repeated exposure.

    Directory of Open Access Journals (Sweden)

    Sanne Griffioen-Roose

    Full Text Available BACKGROUND: The reward value of food is partly dependent on learned associations. It is not yet known whether replacing sugar with non-caloric sweeteners in food is affecting long-term acceptance. OBJECTIVE: To determine the effect of replacing sugar with non-caloric sweeteners in a nutrient-empty drink (soft drink versus nutrient-rich drink (yoghurt drink on reward value after repeated exposure. DESIGN: We used a randomized crossover design whereby forty subjects (15 men, 25 women with a mean ± SD age of 21 ± 2 y and BMI of 21.5 ± 1.7 kg/m(2 consumed a fixed portion of a non-caloric sweetened (NS and sugar sweetened (SS versions of either a soft drink or a yoghurt drink (counterbalanced for breakfast which were distinguishable by means of colored labels. Each version of a drink was offered 10 times in semi-random order. Before and after conditioning the reward value of the drinks was assessed using behavioral tasks on wanting, liking, and expected satiety. In a subgroup (n=18 fMRI was performed to assess brain reward responses to the drinks. RESULTS: Outcomes of both the behavioral tasks and fMRI showed that conditioning did not affect the reward value of the NS and SS versions of the drinks significantly. Overall, subjects preferred the yoghurt drinks to the soft drinks and the ss drinks to the NS drinks. In addition, they expected the yoghurt drinks to be more satiating, they reduced hunger more, and delayed the first eating episode more. Conditioning did not influence these effects. CONCLUSION: Our study showed that repeated consumption of a non-caloric sweetened beverage, instead of a sugar sweetened version, appears not to result in changes in the reward value. It cannot be ruled out that learned associations between sensory attributes and food satiating capacity which developed preceding the conditioning period, during lifetime, affected the reward value of the drinks.

  19. Endangered North Atlantic right whales (Eubalaena glacialis) experience repeated, concurrent exposure to multiple environmental neurotoxins produced by marine algae.

    Science.gov (United States)

    Doucette, Gregory J; Mikulski, Christina M; King, Kristen L; Roth, Patricia B; Wang, Zhihong; Leandro, Luis F; DeGrasse, Stacey L; White, Kevin D; De Biase, Daniela; Gillett, Roxanne M; Rolland, Rosalind M

    2012-01-01

    The western North Atlantic population of right whales (Eubalaena glacialis) is one of the most critically endangered of any whale population in the world. Among the factors considered to have potentially adverse effects on the health and reproduction of E. glacialis are biotoxins produced by certain microalgae responsible for causing harmful algal blooms. The worldwide incidence of these events has continued to increase dramatically over the past several decades and is expected to remain problematic under predicted climate change scenarios. Previous investigations have demonstrated that N. Atlantic right whales are being exposed to at least two classes of algal-produced environmental neurotoxins-paralytic shellfish toxins (PSTs) and domoic acid (DA). Our primary aims during this six-year study (2001-2006) were to assess whether the whales' exposure to these algal biotoxins occurred annually over multiple years, and to what extent individual whales were exposed repeatedly and/or concurrently to one or both toxin classes. Approximately 140 right whale fecal samples obtained across multiple habitats in the western N. Atlantic were analyzed for PSTs and DA. About 40% of these samples were attributed to individual whales in the North Atlantic Right Whale Catalog, permitting analysis of biotoxin exposure according to sex, age class, and reproductive status/history. Our findings demonstrate clearly that right whales are being exposed to both of these algal biotoxins on virtually an annual basis in multiple habitats for periods of up to six months (April through September), with similar exposure rates for females and males (PSTs: ∼70-80%; DA: ∼25-30%). Notably, only one of 14 lactating females sampled did not contain either PSTs or DA, suggesting the potential for maternal toxin transfer and possible effects on neonatal animals. Moreover, 22% of the fecal samples tested for PSTs and DA showed concurrent exposure to both neurotoxins, leading to questions of interactive

  20. Prevention of diabetes in NOD mice by repeated exposures to a contact allergen inducing a sub-clinical dermatitis.

    Directory of Open Access Journals (Sweden)

    Kaare Engkilde

    Full Text Available BACKGROUND: Type 1 diabetes is an autoimmune disease, while allergic contact dermatitis although immune mediated, is considered an exposure driven disease that develops due to epicutaneous contact with reactive low-molecular chemicals. The objective of the present study was to experimentally study the effect of contact allergens on the development of diabetes in NOD mice. As the link between contact allergy and diabetes is yet unexplained we also examined the effect of provocation with allergens on Natural Killer T (NKT cells, since involvement of NKT cells could suggest an innate connection between the two diseases. METHOD: NOD mice 4 weeks of age were exposed, on the ears, to two allergens, p-phenylenediamine and 2,4-dinitrochlorobenzene respectively, to investigate the diabetes development. The mice were followed for a maximum of 32 weeks, and they were either repeatedly exposed to the allergens or only sensitized a week after arrival. The stimulation of NKT cells by the two allergens were additionally studied in C57BL/6 mice. The mice were sensitized and two weeks later provocated with the allergens. The mice were subsequently euthanized at different time points after the provocation. RESULTS: It was found that repeated application of p-phenylenediamine reduced the incidence of diabetes compared to application with water (47% vs. 93%, P = 0.004. Moreover it was shown that in C57BL/6 mice both allergens resulted in a slight increment in the quantity of NKT cells in the liver. Application of the allergens at the same time resulted in an increased number of NKT cells in the draining auricular lymph node, and the increase appeared to be somewhat allergen specific as the accumulation was stronger for p-phenylenediamine. CONCLUSION: The study showed that repeated topical application on the ears with a contact allergen could prevent the development of diabetes in NOD mice. The contact allergens gave a non-visible, sub-clinical dermatitis on the

  1. Prevention of Diabetes in NOD Mice by Repeated Exposures to a Contact Allergen Inducing a Sub-Clinical Dermatitis

    Science.gov (United States)

    Engkilde, Kaare; Buschard, Karsten; Hansen, Axel Kornerup; Menné, Torkil; Johansen, Jeanne Duus

    2010-01-01

    Background Type 1 diabetes is an autoimmune disease, while allergic contact dermatitis although immune mediated, is considered an exposure driven disease that develops due to epicutanous contact with reactive low-molecular chemicals. The objective of the present study was to experimentally study the effect of contact allergens on the development of diabetes in NOD mice. As the link between contact allergy and diabetes is yet unexplained we also examined the effect of provocation with allergens on Natural Killer T (NKT) cells, since involvement of NKT cells could suggest an innate connection between the two diseases. Method NOD mice 4 weeks of age were exposed, on the ears, to two allergens, p-phenylenediamine and 2,4-dinitrochlorobenzene respectively, to investigate the diabetes development. The mice were followed for a maximum of 32 weeks, and they were either repeatedly exposed to the allergens or only sensitized a week after arrival. The stimulation of NKT cells by the two allergens were additionally studied in C57BL/6 mice. The mice were sensitized and two weeks later provocated with the allergens. The mice were subsequently euthanized at different time points after the provocation. Results It was found that repeated application of p-phenylenediamine reduced the incidence of diabetes compared to application with water (47% vs. 93%, P = 0.004). Moreover it was shown that in C57BL/6 mice both allergens resulted in a slight increment in the quantity of NKT cells in the liver. Application of the allergens at the same time resulted in an increased number of NKT cells in the draining auricular lymph node, and the increase appeared to be somewhat allergen specific as the accumulation was stronger for p-phenylenediamine. Conclusion The study showed that repeated topical application on the ears with a contact allergen could prevent the development of diabetes in NOD mice. The contact allergens gave a non-visible, sub-clinical dermatitis on the application site. The

  2. Response of the Hypothalamic-Pituitary-Adrenal System to Repeated Moderate Psychoemotional Stress Exposure Is Associated with Behavioral Parameters.

    Science.gov (United States)

    Goncharova, N D; Chigarova, O A; Oganyan, T E

    2017-05-01

    Individual features of the response of the hypothalamic-pituitary-adrenal axis (HPAA) to repeated moderate stress exposure (daily 2-h restraint stress for 10 days) was studied in young female rhesus monkeys with healthy normal behavior and combined group of female rhesus monkeys with abnormal depression-like and anxious behavior. No between-group differences in the response of ACTH and cortisol were found on day 1. On day 10, a rapid and less pronounced increase in ACTH secretion was observed in all animals in comparison with day 1. Analysis of between-group differences in HPAA response showed higher increase in ACTH level and lower increase in cortisol concentration in animals with depression-like and anxious behavior. These changes were similar to the previously described differences in the response of the adenohypophysis and adrenal cortex to acute restraint stress in old monkeys with similar behavior. Thus, individuals with depression-like and anxious behavior demonstrate impaired stress-induced reactivity of HPAA as early as in young age.

  3. Inhibition of voltage-gated calcium channels after subchronic and repeated exposure of PC12 cells to different classes of insecticides

    NARCIS (Netherlands)

    Meijer, Marieke; Brandsema, Joske A R; Nieuwenhuis, Desirée; Wijnolts, Fiona M J; Dingemans, Milou M L; Westerink, Remco H S

    2015-01-01

    We previously demonstrated that acute inhibition of voltage-gated calcium channels (VGCCs) is a common mode of action for (sub)micromolar concentrations of chemicals, including insecticides. However, since human exposure to chemicals is usually chronic and repeated, we investigated if selected insec

  4. Inhibition of voltage-gated calcium channels after subchronic and repeated exposure of PC12 cells to different classes of insecticides

    NARCIS (Netherlands)

    Meijer, Marieke; Brandsema, Joske A R; Nieuwenhuis, Desirée; Wijnolts, Fiona M J; Dingemans, Milou M L|info:eu-repo/dai/nl/304834564; Westerink, Remco H S|info:eu-repo/dai/nl/239425952

    2015-01-01

    We previously demonstrated that acute inhibition of voltage-gated calcium channels (VGCCs) is a common mode of action for (sub)micromolar concentrations of chemicals, including insecticides. However, since human exposure to chemicals is usually chronic and repeated, we investigated if selected insec

  5. Anti-Inflammatory and Antioxidant Effects of Repeated Exposure to Cruciferous Allyl Nitrile in Sensitizer-Induced Ear Edema in Mice.

    Science.gov (United States)

    Tanii, Hideji; Sugitani, Kayo; Saijoh, Kiyofumi

    2016-02-29

    Skin sensitizers induce allergic reactions through the induction of reactive oxygen species. Allyl nitrile from cruciferous vegetables has been reported to induce antioxidants and phase II detoxification enzymes in various tissues. We assessed the effects of repeated exposure to allyl nitrile on sensitizer-induced allergic reactions. Mice were dosed with allyl nitrile (0-200 µmol/kg), and then received a dermal application of 1 of 3 sensitizers on the left ear or 1 of 2 vehicles on the right ear. Quantitative assessment of edema was carried out by measuring the difference in weight between the portions taken from the right and left ears. We tested enzymes (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and thiobarbituric acid reactive substances (TBARS) in ears. Repeated exposure to allyl nitrile reduced edemas induced by glutaraldehyde and by 2, 4-dinitrochlorobenzene (DNCB), but not by formaldehyde. The repeated exposure decreased levels of TBARS, a marker of oxidative stress, induced by glutaraldehyde and by DNCB, but not by formaldehyde. Allyl nitrile elevated SOD levels for the 3 sensitizers, and CAT levels for formaldehyde and DNCB. Allyl nitrile also increased GPx levels for formaldehyde and DNCB, but not for glutaraldehyde. The reduced edemas were associated with changes in oxidative stress levels and antioxidant enzymes. Repeated exposure to allyl nitrile reduced allergic reactions induced by glutaraldehyde and by DNCB, but not by formaldehyde. This reduction was associated with changes in ROS levels and antioxidant enzyme activities.

  6. Cholinesterase inhibition and depression of the photic after discharge of flash evoked potentials following acute or repeated exposures to a mixture of carbaryl and propoxur.

    Science.gov (United States)

    Mwanza, Jean-Claude; Lyke, Danielle F; Hertzberg, Richard C; Haber, Lynne; Kohrman-Vincent, Melissa; Li, Ruosha; Pan, Yi; Lyles, Robert H; Simmons, Jane Ellen; Macmillan, Denise K; Zehr, R Dan; Swank, Adam E; Herr, David W

    2012-06-01

    Previously, we reported that acute treatment with propoxur or carbaryl decreased the duration of the photic after discharge (PhAD) of flash evoked potentials (FEPs). In the current studies, we compared the effects of acute or repeated exposure to a mixture of carbaryl and propoxur (1:1.45 ratio; propoxur:carbaryl) on the duration of the PhAD and brain ChE activity in Long Evans rats. Animals were exposed (po) either to a single dose (0, 3, 10, 45 or 75 mg/kg), or 14 daily dosages (0, 3, 10, 30, 45 mg/kg), of the mixture. Acute and repeated treatment with 3mg/kg (or greater) of the mixture produced dose-related inhibition of brain ChE activity. Compared to controls, the PhAD duration decreased after acute administration of 75 mg/kg or repeated treatment with 30 mg/kg of the mixture. The linear relationship between the percent of control brain ChE activity and the PhAD duration was similar for both exposure paradigms. Dose-response models for the acute and repeated exposure data did not differ for brain ChE activity or the duration of the PhAD. Repeated treatment with the mixture resulted in slightly less (13-22%) erythrocyte ChE inhibition than acute exposure. Both acute and repeated treatment resulted in dose-additive results for the PhAD duration and less than dose-additive responses (6-16%) for brain ChE activity for the middle range of dosages. Acute treatment resulted in greater than dose-additive erythrocyte ChE inhibition (15-18%) at the highest dosages. In contrast, repeated treatment resulted in less than dose-additive erythrocyte ChE inhibition (16-22%) at the middle dosages. Brain and plasma levels of propoxur and carbaryl did not differ between the acute and repeated dosing paradigms. In summary, a physiological measure of central nervous system function and brain ChE activity had similar responses after acute or repeated treatment with the carbamate mixture, and brain ChE showed only small deviations from dose-additivity. Erythrocyte ChE activity had

  7. Effects of short-term repeated exposure to different flooring surfaces on the behavior and physiology of dairy cattle.

    Science.gov (United States)

    Schütz, K E; Cox, N R

    2014-05-01

    during the stand-off period. We observed no major effect of the repeated stand-off exposure. In summary, adding rubber matting onto concrete surfaces for stand-off purposes is beneficial for animal welfare. A well-managed wood chip surface offered the best welfare for dairy cows removed from pasture, and the findings of this study confirm that a concrete surface decreases the welfare of cows removed from pasture.

  8. Distribution of silver in rats following 28 days of repeated oral exposure to silver nanoparticles or silver acetate

    Science.gov (United States)

    2011-01-01

    Background The study investigated the distribution of silver after 28 days repeated oral administration of silver nanoparticles (AgNPs) and silver acetate (AgAc) to rats. Oral administration is a relevant route of exposure because of the use of silver nanoparticles in products related to food and food contact materials. Results AgNPs were synthesized with a size distribution of 14 ± 4 nm in diameter (90% of the nanoparticle volume) and stabilized in aqueous suspension by the polymer polyvinylpyrrolidone (PVP). The AgNPs remained stable throughout the duration of the 28-day oral toxicity study in rats. The organ distribution pattern of silver following administration of AgNPs and AgAc was similar. However the absolute silver concentrations in tissues were lower following oral exposure to AgNPs. This was in agreement with an indication of a higher fecal excretion following administration of AgNPs. Besides the intestinal system, the largest silver concentrations were detected in the liver and kidneys. Silver was also found in the lungs and brain. Autometallographic (AMG) staining revealed a similar cellular localization of silver in ileum, liver, and kidney tissue in rats exposed to AgNPs or AgAc. Using transmission electron microscopy (TEM), nanosized granules were detected in the ileum of animals exposed to AgNPs or AgAc and were mainly located in the basal lamina of the ileal epithelium and in lysosomes of macrophages within the lamina propria. Using energy dispersive x-ray spectroscopy it was shown that the granules in lysosomes consisted of silver, selenium, and sulfur for both AgNP and AgAc exposed rats. The diameter of the deposited granules was in the same size range as that of the administered AgNPs. No silver granules were detected by TEM in the liver. Conclusions The results of the present study demonstrate that the organ distribution of silver was similar when AgNPs or AgAc were administered orally to rats. The presence of silver granules containing

  9. Distribution of silver in rats following 28 days of repeated oral exposure to silver nanoparticles or silver acetate

    Directory of Open Access Journals (Sweden)

    Mortensen Alicja

    2011-06-01

    Full Text Available Abstract Background The study investigated the distribution of silver after 28 days repeated oral administration of silver nanoparticles (AgNPs and silver acetate (AgAc to rats. Oral administration is a relevant route of exposure because of the use of silver nanoparticles in products related to food and food contact materials. Results AgNPs were synthesized with a size distribution of 14 ± 4 nm in diameter (90% of the nanoparticle volume and stabilized in aqueous suspension by the polymer polyvinylpyrrolidone (PVP. The AgNPs remained stable throughout the duration of the 28-day oral toxicity study in rats. The organ distribution pattern of silver following administration of AgNPs and AgAc was similar. However the absolute silver concentrations in tissues were lower following oral exposure to AgNPs. This was in agreement with an indication of a higher fecal excretion following administration of AgNPs. Besides the intestinal system, the largest silver concentrations were detected in the liver and kidneys. Silver was also found in the lungs and brain. Autometallographic (AMG staining revealed a similar cellular localization of silver in ileum, liver, and kidney tissue in rats exposed to AgNPs or AgAc. Using transmission electron microscopy (TEM, nanosized granules were detected in the ileum of animals exposed to AgNPs or AgAc and were mainly located in the basal lamina of the ileal epithelium and in lysosomes of macrophages within the lamina propria. Using energy dispersive x-ray spectroscopy it was shown that the granules in lysosomes consisted of silver, selenium, and sulfur for both AgNP and AgAc exposed rats. The diameter of the deposited granules was in the same size range as that of the administered AgNPs. No silver granules were detected by TEM in the liver. Conclusions The results of the present study demonstrate that the organ distribution of silver was similar when AgNPs or AgAc were administered orally to rats. The presence of silver

  10. Distribution of silver in rats following 28 days of repeated oral exposure to silver nanoparticles or silver acetate.

    Science.gov (United States)

    Loeschner, Katrin; Hadrup, Niels; Qvortrup, Klaus; Larsen, Agnete; Gao, Xueyun; Vogel, Ulla; Mortensen, Alicja; Lam, Henrik Rye; Larsen, Erik H

    2011-06-01

    The study investigated the distribution of silver after 28 days repeated oral administration of silver nanoparticles (AgNPs) and silver acetate (AgAc) to rats. Oral administration is a relevant route of exposure because of the use of silver nanoparticles in products related to food and food contact materials. AgNPs were synthesized with a size distribution of 14 ± 4 nm in diameter (90% of the nanoparticle volume) and stabilized in aqueous suspension by the polymer polyvinylpyrrolidone (PVP). The AgNPs remained stable throughout the duration of the 28-day oral toxicity study in rats. The organ distribution pattern of silver following administration of AgNPs and AgAc was similar. However the absolute silver concentrations in tissues were lower following oral exposure to AgNPs. This was in agreement with an indication of a higher fecal excretion following administration of AgNPs. Besides the intestinal system, the largest silver concentrations were detected in the liver and kidneys. Silver was also found in the lungs and brain. Autometallographic (AMG) staining revealed a similar cellular localization of silver in ileum, liver, and kidney tissue in rats exposed to AgNPs or AgAc. Using transmission electron microscopy (TEM), nanosized granules were detected in the ileum of animals exposed to AgNPs or AgAc and were mainly located in the basal lamina of the ileal epithelium and in lysosomes of macrophages within the lamina propria. Using energy dispersive x-ray spectroscopy it was shown that the granules in lysosomes consisted of silver, selenium, and sulfur for both AgNP and AgAc exposed rats. The diameter of the deposited granules was in the same size range as that of the administered AgNPs. No silver granules were detected by TEM in the liver. The results of the present study demonstrate that the organ distribution of silver was similar when AgNPs or AgAc were administered orally to rats. The presence of silver granules containing selenium and sulfur in the

  11. A review of the reporting and handling of missing data in cohort studies with repeated assessment of exposure measures

    Directory of Open Access Journals (Sweden)

    Karahalios Amalia

    2012-07-01

    Full Text Available Abstract Background Retaining participants in cohort studies with multiple follow-up waves is difficult. Commonly, researchers are faced with the problem of missing data, which may introduce biased results as well as a loss of statistical power and precision. The STROBE guidelines von Elm et al. (Lancet, 370:1453-1457, 2007; Vandenbroucke et al. (PLoS Med, 4:e297, 2007 and the guidelines proposed by Sterne et al. (BMJ, 338:b2393, 2009 recommend that cohort studies report on the amount of missing data, the reasons for non-participation and non-response, and the method used to handle missing data in the analyses. We have conducted a review of publications from cohort studies in order to document the reporting of missing data for exposure measures and to describe the statistical methods used to account for the missing data. Methods A systematic search of English language papers published from January 2000 to December 2009 was carried out in PubMed. Prospective cohort studies with a sample size greater than 1,000 that analysed data using repeated measures of exposure were included. Results Among the 82 papers meeting the inclusion criteria, only 35 (43% reported the amount of missing data according to the suggested guidelines. Sixty-eight papers (83% described how they dealt with missing data in the analysis. Most of the papers excluded participants with missing data and performed a complete-case analysis (n = 54, 66%. Other papers used more sophisticated methods including multiple imputation (n = 5 or fully Bayesian modeling (n = 1. Methods known to produce biased results were also used, for example, Last Observation Carried Forward (n = 7, the missing indicator method (n = 1, and mean value substitution (n = 3. For the remaining 14 papers, the method used to handle missing data in the analysis was not stated. Conclusions This review highlights the inconsistent reporting of missing data in cohort studies and the continuing

  12. A review of the reporting and handling of missing data in cohort studies with repeated assessment of exposure measures.

    Science.gov (United States)

    Karahalios, Amalia; Baglietto, Laura; Carlin, John B; English, Dallas R; Simpson, Julie A

    2012-07-11

    Retaining participants in cohort studies with multiple follow-up waves is difficult. Commonly, researchers are faced with the problem of missing data, which may introduce biased results as well as a loss of statistical power and precision. The STROBE guidelines von Elm et al. (Lancet, 370:1453-1457, 2007); Vandenbroucke et al. (PLoS Med, 4:e297, 2007) and the guidelines proposed by Sterne et al. (BMJ, 338:b2393, 2009) recommend that cohort studies report on the amount of missing data, the reasons for non-participation and non-response, and the method used to handle missing data in the analyses. We have conducted a review of publications from cohort studies in order to document the reporting of missing data for exposure measures and to describe the statistical methods used to account for the missing data. A systematic search of English language papers published from January 2000 to December 2009 was carried out in PubMed. Prospective cohort studies with a sample size greater than 1,000 that analysed data using repeated measures of exposure were included. Among the 82 papers meeting the inclusion criteria, only 35 (43%) reported the amount of missing data according to the suggested guidelines. Sixty-eight papers (83%) described how they dealt with missing data in the analysis. Most of the papers excluded participants with missing data and performed a complete-case analysis (n=54, 66%). Other papers used more sophisticated methods including multiple imputation (n=5) or fully Bayesian modeling (n=1). Methods known to produce biased results were also used, for example, Last Observation Carried Forward (n=7), the missing indicator method (n=1), and mean value substitution (n=3). For the remaining 14 papers, the method used to handle missing data in the analysis was not stated. This review highlights the inconsistent reporting of missing data in cohort studies and the continuing use of inappropriate methods to handle missing data in the analysis. Epidemiological journals

  13. Protection Efficacy of the Extract of Ginkgo biloba against the Learning and Memory Damage of Rats under Repeated High Sustained +Gz Exposure

    Directory of Open Access Journals (Sweden)

    Liang-En Chen

    2016-01-01

    Full Text Available Repeated high sustained positive Gz (+Gz exposures are known for the harmful pathophysiological impact on the brain of rats, which is reflected as the interruption of normal performance of learning and memory. Interestingly, extract of Ginkgo biloba (EGb has been reported to have neuroprotective effects and cognition-enhancing effects. In this study, we are interested in evaluating the protective effects of EGb toward the learning and memory abilities. Morris Water Maze Test (MWM was used to evaluate the cognitive function, and the physiological status of the key components in central cholinergic system was also investigated. Our animal behavioral tests indicated that EGb can release the learning and memory impairment caused by repeated high sustained +Gz. Administration of EGb to rats can diminish some of the harmful physiological effects caused by repeated +Gz exposures. Moreover, EGb administration can increase the biological activities of superoxide dismutase (SOD and glutathione peroxidase (GSH-Px but reduce the production of malondialdehyde (MDA. Taken together, our study showed that EGb can ameliorate the impairment of learning and memory abilities of rats induced by repeated high sustained +Gz exposure; the underlying mechanisms appeared to be related to the signal regulation on the cholinergic system and antioxidant enzymes system.

  14. 'Just a pinch of salt'. An experimental comparison of the effect of repeated exposure and flavor-flavor learning with salt or spice on vegetable acceptance in toddlers.

    Science.gov (United States)

    Bouhlal, Sofia; Issanchou, Sylvie; Chabanet, Claire; Nicklaus, Sophie

    2014-12-01

    Children's vegetable intake is below the recommended amounts. No studies to date have tested the relevance of using salt or spices to increase children's vegetable acceptance. Our objective was to compare the effect of repeated exposure (RE) and of flavor-flavor learning (FFL) on toddlers' acceptance of a non-familiar vegetable. Two unconditioned stimuli were used: salt and a salt-associated spice. Toddlers attending six nurseries were assigned to 3 groups in a between subject design. Groups were exposed 8 times to a basic salsify puree (0.2% salt w/w; RE group; n = 47), a salty salsify puree (0.5% salt w/w; FFL-Salt group; n = 54) or a spiced salsify puree (0.2% salt and 0.02% nutmeg w/w; FFL-Nutmeg group; n = 50). Acceptance (intake and liking) of the target vegetable (basic salsify puree) and of a control vegetable (carrot puree) was evaluated at pre-exposure, at each exposure of the learning period, at post-exposure, and at 1, 3 and 6 months after exposure. In all groups, intake of the target vegetable increased from pre- to post-exposure. This increase was significantly higher in the RE group (64 ± 11 g) than in the FFL-Salt group (23 ± 11 g) and marginally higher than in the FFL-Nutmeg group (36 ± 11 g). No difference between groups was observed on the increase in liking of the target vegetable from pre- to post-exposure. The increase of the target vegetable intake was still observed after 6 months for all groups. Thus, repeated exposure appears to be the simplest choice to increase vegetable intake on the short and long term in toddlers. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Repeated exposure to cat urine induces complex behavioral, hormonal, and c-fos mRNA responses in Norway rats ( Rattus norvegicus)

    Science.gov (United States)

    Yin, Baofa; Gu, Chen; Lu, Yi; Hegab, Ibrahim M.; Yang, Shengmei; Wang, Aiqin; Wei, Wanhong

    2017-08-01

    Prey species show specific adaptations that allow recognition, avoidance, and defense against predators. This study was undertaken to investigate the processing of a chronic, life-threatening stimulus to Norway rats ( Rattus norvegicus). One hundred forty-four Norway rats were tested by repeated presentation of cat urine for 1 h at different days in a defensive withdrawal apparatus. Rats exposed to urine for short periods showed significantly larger defensive behavioral and medial hypothalamic c-fos messenger RNA (mRNA) responses than other groups. These defensive responses habituated shortly after the presentation of cat urine. Serum levels of adrenocorticotropic hormone and corticosterone increased significantly when animals were repeatedly exposed to cat urine. However, the hormonal responses took longer to habituate than the behavioral and molecular responses did. We conclude that the behavioral and c-fos mRNA responses are "primed" for habituation to repeated exposures to cat urine, while the hormonal responses show "resistance." The results support our hypothesis that the strongest anti-predator responses at three levels would occur during short-term exposure to cat urine and that these responses would subsequently disappear on prolonged exposure. This study assists understanding the way in which the different levels of defensive responses are integrated and react during chronic stress.

  16. Exposure to repeated immobilization stress inhibits cocaine-induced increase in dopamine extracellular levels in the rat ventral tegmental area.

    Science.gov (United States)

    Sotomayor-Zárate, Ramón; Abarca, Jorge; Araya, Katherine A; Renard, Georgina M; Andrés, María E; Gysling, Katia

    2015-11-01

    A higher vulnerability to drug abuse has been observed in human studies of individuals exposed to chronic or persistent stress, as well as in animal models of drug abuse. Here, we explored the effect of repeated immobilization stress on cocaine-induced increase in dopamine extracellular levels in VTA and its regulation by corticotropin-releasing factor (CRF) and GABA systems. Cocaine (10mg/Kg i.p.) induced an increase of VTA DA extracellular levels in control rats. However, this effect was not observed in repeated stress rats. Considering the evidence relating stress with CRF, we decided to perfuse CRF and CP-154526 (selective antagonist of CRF1 receptor) in the VTA of control and repeated stress rats, respectively. We observed that perfusion of 20μM CRF inhibited the increase of VTA DA extracellular levels induced by cocaine in control rats. Interestingly, we observed that in the presence of 10μM CP-154526, cocaine induced a significant increase of VTA DA extracellular levels in repeated stress rats. Regarding the role of VTA GABA neurotransmission, cocaine administration induced a significant increase in VTA GABA extracellular levels only in repeated stress rats. Consistently, cocaine was able to increase VTA DA extracellular levels in repeated stress rats when 100μM bicuculline, an antagonist of GABAA receptor, was perfused intra VTA. Thus, both CRF and GABA systems are involved in the lack of response to cocaine in the VTA of repeated stress rats. It is tempting to suggest that the loss of response in VTA dopaminergic neurons to cocaine, after repeated stress, is due to an interaction between CRF and GABA systems. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Alteration of brain levels of neurotransmitters and amino acids in male F344 rats induced by three-week repeated inhalation exposure to 1-bromopropane.

    Science.gov (United States)

    Suda, Megumi; Honma, Takeshi; Miyagawa, Muneyuki; Wang, Rui-Sheng

    2008-08-01

    The present study investigated the effects of 1-bromopropane (1BP) on brain neuroactive substances of rats to determine the extent of its toxicity to the central nervous system (CNS). We measured the changes in neurotransmitters (acetylcholine, catecholamine, serotonin and amino acids) and their metabolites or precursors in eight brain regions after inhalation exposure to 1BP at 50 to 1,000 ppm for 8 h per day for 7 d per week for 3 wk. Rats were sacrificed at 2 h (Case 1), or at 19 h (Case 2) after the end of exposure. In Case 1, the level of 5-hydroxyindoleacetic acid (5HIAA) was lowered in some brain regions by 1BP exposure. The decrease of 5HIAA in the frontal cortex was statistically significant at 50 ppm 1BP exposure. In Case 2, gamma-amino butyric acid (GABA) and taurine were decreased in many brain regions of exposed rats, and a significant decrease of taurine in the midbrain occurred at 50 ppm 1BP exposure. In both cases of 2-h and 19-h intervals from the end of exposure to sacrifice, aspartate and glutamine levels were elevated in many brain regions, but the acetylcholine level did not change in any brain region. Three-week repeated exposure to 1BP produced significantly changes in amino acid contents of rat brains, particularly at 1,000 ppm.

  18. Histopathology of repeated, intermittent exposure of chloramine-T to walleye (Sander vitreum) and (Ictalurus punctalus) channel catfish

    Science.gov (United States)

    Gaikowski, M.P.; Densmore, Christine L.; Blazer, V.S.

    2009-01-01

    Chloramine-T (Cl-T) has been used safely and effectively to control bacterial gill disease in salmonids at a maximum exposure regimen of up to four consecutive, once-daily exposures administered for 60??min at 20??mg/L. However, data to document safe treatment concentrations of Cl-T are lacking for freshwater-reared fish other than salmonids. We report the histopathology resultant from the administration of 12 consecutive, once-daily, 180-min static immersion baths of 0, 20, 50, or 80??mg Cl-T/L to walleye (20????C) and channel catfish (27????C). Twelve fish of each species were euthanized immediately before the first exposure (initial controls) and then after the twelfth exposure and 7 and 14??days after the twelfth exposure. Only initial controls and fish euthanized immediately after the twelfth exposure were processed for histological review because of the general lack of exposure-related lesions in exposed fish. The only exposure-related histological changes were in the spleen where significantly greater erythrocyte swelling and necrosis was observed in channel catfish exposed at 80??mg/L relative to exposure at 0??mg/L; similar histological changes were insignificant for walleye, though there appeared to be a shift in the general category of histological change with degenerative changes (necrosis, etc.) observed following exposure at 50 or 80??mg/L compared to the inflammatory and hemodynamic changes (congestion, leukocyte infiltrate, etc.) observed in walleye exposed at 0 or 20??mg/L. The only significant change in peripheral blood cytology was that walleye fingerlings exposed at 80??mg/L had significantly fewer mature red blood cells and significantly more immature red blood cells per oil-immersion field than controls. The histopathological changes observed following exposure to Cl-T under an exaggerated exposure regimen suggest that walleye or channel catfish therapeutically exposed to Cl-T will not have treatment-related histological changes.

  19. GT-repeat polymorphism in the heme oxygenase-1 gene promoter and the risk of carotid atherosclerosis related to arsenic exposure

    Directory of Open Access Journals (Sweden)

    Wu Meei-Maan

    2010-08-01

    Full Text Available Abstract Background Arsenic is a strong stimulus of heme oxygenase (HO-1 expression in experimental studies in response to oxidative stress caused by a stimulus. A functional GT-repeat polymorphism in the HO-1 gene promoter was inversely correlated to the development of coronary artery disease in diabetics and development of restenosis following angioplasty in patients. The role of this potential vascular protective factor in carotid atherosclerosis remains unclear. We previously reported a graded association of arsenic exposure in drinking water with an increased risk of carotid atherosclerosis. In this study, we investigated the relationship between HO-1 genetic polymorphism and the risk of atherosclerosis related to arsenic. Methods Three-hundred and sixty-seven participants with an indication of carotid atherosclerosis and an additional 420 participants without the indication, which served as the controls, from two arsenic exposure areas in Taiwan, a low arsenic-exposed Lanyang cohort and a high arsenic-exposed LMN cohort, were studied. Carotid atherosclerosis was evaluated using a duplex ultrasonographic assessment of the extracranial carotid arteries. Allelic variants of (GTn repeats in the 5'-flanking region of the HO-1 gene were identified and grouped into a short (S allele ( Results Analysis results showed that arsenic's effect on carotid atherosclerosis differed between carriers of the class S allele (OR 1.39; 95% CI 0.86-2.25; p = 0.181 and non-carriers (OR 2.65; 95% CI 1.03-6.82; p = 0.044 in the high-exposure LMN cohort. At arsenic exposure levels exceeding 750 μg/L, difference in OR estimates between class S allele carriers and non-carriers was borderline significant (p = 0.051. In contrast, no such results were found in the low-exposure Lanyang cohort. Conclusions This exploratory study suggests that at a relatively high level of arsenic exposure, carriers of the short (GTn allele (

  20. Field study of the urinary excretion of ethoxyacetic acid during repeated daily exposure to the ethyl ether of ethylene glycol and the ethyl ether of ethylene glycol acetate.

    Science.gov (United States)

    Veulemans, H; Groeseneken, D; Masschelein, R; Van Vlem, E

    1987-06-01

    The urinary excretion of ethoxyacetic acid (EAA) was studied in a group of five women daily exposed to the ethyl ether of ethylene glycol (EGEE) and the ethyl ether of ethylene glycol acetate (EGEE-Ac) during 5 d of normal production and 7 d after a 12-d production stop. The mean combined exposure concentration of EGEE and EGEE-Ac (expressed in equivalent weight of EGEE) was 14.0 mg/m3 with occasional slight excursions above the current Belgian occupational exposure limit. The daily combined exposure profiles for EGEE and EGEE-Ac were rather constant during the first observation period, but they tended to decrease during the last week. The urinary EAA excretion clearly increased during the work week. Over the weekends the elimination was far from complete, and even after a prolonged nonexposure period of 12 d traces of the metabolite were still detectable. Based on the observations from the first period, a good linear correlation (r = 0.92) was found between the average exposure over 5 d (14.4 mg/m3) and the EAA excretion at the end of the week (105.7 mg/g creatinine). An EAA estimate of 150 +/- 35 mg/g was found to correspond with repeated 5-d full-shift exposures to the respective occupational exposure limit of EGEE (19 mg/m3) or EGEE-Ac (27 mg/m3).

  1. Narrative exposure therapy for posttraumatic stress disorder associated with repeated interpersonal trauma in patients with severe mental illness: a mixed methods design

    Science.gov (United States)

    Mauritz, Maria W.; Van Gaal, Betsie G. I.; Jongedijk, Ruud A.; Schoonhoven, Lisette; Nijhuis-van der Sanden, Maria W. G.; Goossens, Peter J. J.

    2016-01-01

    Background In the Netherlands, most patients with severe mental illness (SMI) receive flexible assertive community treatment (FACT) provided by multidisciplinary community mental health teams. SMI patients with comorbid posttraumatic stress disorder (PTSD) are sometimes offered evidence-based trauma-focused treatment like eye movement desensitization reprocessing or prolonged exposure. There is a large amount of evidence for the effectiveness of narrative exposure therapy (NET) within various vulnerable patient groups with repeated interpersonal trauma. Some FACT-teams provide NET for patients with comorbid PTSD, which is promising, but has not been specifically studied in SMI patients. Objectives The primary aim is to evaluate NET in SMI patients with comorbid PTSD associated with repeated interpersonal trauma to get insight into whether (1) PTSD and dissociative symptoms changes and (2) changes occur in the present SMI symptoms, care needs, quality of life, global functioning, and care consumption. The second aim is to gain insight into patients’ experiences with NET and to identify influencing factors on treatment results. Methods This study will have a mixed methods convergent design consisting of quantitative repeated measures and qualitative semi-structured in-depth interviews based on Grounded Theory. The study population will include adult SMI outpatients (n=25) with comorbid PTSD and receiving NET. The quantitative study parameters will be existence and severity of PTSD, dissociative, and SMI symptoms; care needs; quality of life; global functioning; and care consumption. In a longitudinal analysis, outcomes will be analyzed using mixed models to estimate the difference in means between baseline and repeated measurements. The qualitative study parameters will be experiences with NET and perceived factors for success or failure. Integration of quantitative and qualitative results will be focused on interpreting how qualitative results enhance the

  2. Allergic inflammation in the upper respiratory tract of the rat upon repeated inhalation exposure to the contact allergen dinitrochlorobenzene (DNCB).

    NARCIS (Netherlands)

    Triel, J.J. van; Arts, J.H.; Muijser, H.; Kuper, C.F.

    2010-01-01

    Previously, the contact allergen dinitrochlorobenzene (DNCB) was identified as a sensitizer by inhalation in BALB/c mice; in addition, DNCB induced a lymphocytic infiltrate in the larynx of dermally sensitized Th1-prone Wistar rats upon a single inhalation challenge. In the present study, repeated

  3. Repeated exposure to heat stress results in a diaphragm phenotype that resists ventilator-induced diaphragm dysfunction.

    Science.gov (United States)

    Yoshihara, Toshinori; Ichinoseki-Sekine, Noriko; Kakigi, Ryo; Tsuzuki, Takamasa; Sugiura, Takao; Powers, Scott K; Naito, Hisashi

    2015-11-01

    Controlled mechanical ventilation (CMV) is a life-saving intervention for patients in respiratory failure. Unfortunately, prolonged mechanical ventilation (MV) results in diaphragmatic atrophy and contractile dysfunction, both of which are predicted to contribute to problems in weaning patients from the ventilator. Therefore, developing a strategy to protect the diaphragm against ventilator-induced weakness is important. We tested the hypothesis that repeated bouts of heat stress result in diaphragm resistance against CMV-induced atrophy and contractile dysfunction. Male Wistar rats were randomly divided into six experimental groups: 1) control; 2) single bout of whole body heat stress; 3) repeated bouts of whole body heat stress; 4) 12 h CMV; 5) single bout of whole body heat stress 24 h before CMV; and 6) repeated bouts of whole body heat stress 1, 3, and 5 days before 12 h of CMV. Our results revealed that repeated bouts of heat stress resulted in increased levels of heat shock protein 72 in the diaphragm and protection against both CMV-induced diaphragmatic atrophy and contractile dysfunction at submaximal stimulation frequencies. The specific mechanisms responsible for this protection remain unclear: this heat stress-induced protection against CMV-induced diaphragmatic atrophy and weakness may be partially due to reduced diaphragmatic oxidative stress, diminished activation of signal transducer/transcriptional activator-3, lower caspase-3 activation, and decreased autophagy in the diaphragm.

  4. Allergic inflammation in the upper respiratory tract of the rat upon repeated inhalation exposure to the contact allergen dinitrochlorobenzene (DNCB).

    NARCIS (Netherlands)

    Triel, J.J. van; Arts, J.H.; Muijser, H.; Kuper, C.F.

    2010-01-01

    Previously, the contact allergen dinitrochlorobenzene (DNCB) was identified as a sensitizer by inhalation in BALB/c mice; in addition, DNCB induced a lymphocytic infiltrate in the larynx of dermally sensitized Th1-prone Wistar rats upon a single inhalation challenge. In the present study, repeated i

  5. Detection of local inflammation induced by repeated exposure to contact allergens by use of IVIS SpectrumCT analyses

    DEFF Research Database (Denmark)

    Nielsen, Morten M; Schmidt, Jonas Damgård; Christensen, Jan P

    2017-01-01

    BACKGROUND: Contact allergy is characterized by local skin inflammation that, in some cases, can result in systemic immune activation. OBJECTIVES: To investigate whether IVIS SpectrumCT analyses can be used to detect the immune response induced by contact allergens. METHODS: Mice were repeatedly ...

  6. Effects of repeated hyperbaric nitrogen-oxygen exposures on the striatal dopamine release and on motor disturbances in rats.

    Science.gov (United States)

    Lavoute, Cécile; Weiss, Michel; Rostain, Jean-Claude

    2005-09-14

    Previous studies have demonstrated disruptions of motor activities and a decrease of extracellular dopamine level in the striatum of rats exposed to high pressure of nitrogen. Men exposed to nitrogen pressure develop also motor and cognitive disturbances related to inert gas narcosis. After repetitive exposures, adaptation to narcosis was subjectively reported. To study the effects of repetitive exposures to hyperbaric nitrogen-oxygen, male Sprague-Dawley rats were implanted in the striatum with multifiber carbon dopamine-sensitive electrodes. After recovery from surgery, free-moving rats were exposed for 2 h up to 3 MPa of nitrogen-oxygen mixture before and after one daily exposure to 1 MPa of nitrogen-oxygen, for 5 consecutive days. Dopamine release was measured by differential pulse voltammetry and motor activities were quantified using piezo-electric captor. At the first exposure to 3 MPa, the striatal dopamine level decreased during the compression (-15%) to reach -20% during the stay at 3 MPa. Motor activities were increased during compression (+15%) and the first 60 min at constant pressure (+10%). In contrast, at the second exposure to 3 MPa, an increase of dopamine of +15% was obtained during the whole exposure. However, total motor activities remained unchanged as compared to the first exposure. Our results confirm that nitrogen exposure at 3 MPa led to a decreased striatal dopamine release and increased motor disturbances in naïve rats. Repetitive exposures to 1 MPa of nitrogen induced a reversal effect on the dopamine release which suggests a neurochemical change at the level of the neurotransmitter regulation processes of the basal ganglia. In contrast, motor activity remained quantitatively unchanged, thus suggesting that dopamine is not involved alone in modulating these motor disturbances.

  7. Decreased level of Nurr1 in heterozygous young adult mice leads to exacerbated acute and long-term toxicity after repeated methamphetamine exposure.

    Directory of Open Access Journals (Sweden)

    Yu Luo

    Full Text Available The abuse of psychostimulants, such as methamphetamine (METH, is prevalent in young adults and could lead to long-term adaptations in the midbrain dopamine system in abstinent human METH abusers. Nurr1 is a gene that is critical for the survival and maintenance of dopaminergic neurons and has been implicated in dopaminergic neuron related disorders. In this study, we examined the synergistic effects of repeated early exposure to methamphetamine in adolescence and reduction in Nurr1 gene levels. METH binge exposure in adolescence led to greater damage in the nigrostrial dopaminergic system when mice were exposed to METH binge later in life, suggesting a long-term adverse effect on the dopaminergic system. Compared to naïve mice that received METH binge treatment for the first time, mice pretreated with METH in adolescence showed a greater loss of tyrosine hydroxylase (TH immunoreactivity in striatum, loss of THir fibers in the substantia nigra reticulata (SNr as well as decreased dopamine transporter (DAT level and compromised DA clearance in striatum. These effects were further exacerbated in Nurr1 heterozygous mice. Our data suggest that a prolonged adverse effect exists following adolescent METH binge exposure which may lead to greater damage to the dopaminergic system when exposed to repeated METH later in life. Furthermore, our data support that Nurr1 mutations or deficiency could be a potential genetic predisposition which may lead to higher vulnerability in some individuals.

  8. Repeated measures of inflammation, blood pressure, and heart rate variability associated with personal traffic exposures in healthy adults

    Science.gov (United States)

    BACKGROUND: Previous human exposure studies of traffic-related air pollutants have demonstrated adverse health effects in human populations by comparing areas of high and low traffic, but few studies have utilized microenvironmental monitoring of pollutants at multiple traffic lo...

  9. Repeated measures of inflammation, blood pressure, and heart rate variability associated with personal traffic exposures in healthy adults

    Science.gov (United States)

    BACKGROUND: Previous human exposure studies of traffic-related air pollutants have demonstrated adverse health effects in human populations by comparing areas of high and low traffic, but few studies have utilized microenvironmental monitoring of pollutants at multiple traffic lo...

  10. The effect of sensory-nutrient congruency on food intake after repeated exposure: do texture and/or energy density matter?

    Science.gov (United States)

    Hogenkamp, P S

    2014-09-01

    Sensory properties guide the amount that people eat. In particular, food texture plays an important role in a food's 'expected satiation', which in turn affects the food-related decision making process. One hypothesis is that incongruent pairing of a textural cue with a post-ingestive outcome compromises this process, leading to poor energy compensation. Several studies examined the effect of both energy density and sensory characteristics (i.e. increased creaminess and thickness) on expectations, subjective appetite and food intake. To add to this literature, a re-analysis of data assessed whether the effect of sensory-nutrient pairings on energy intake compensation persisted after repeated exposure to a food. In this cross-over design, 27 participants consumed two preloads with 'congruent' (low-energy/liquid; high-energy/semi-solid) and two preloads with 'incongruent' (low-energy/semi-solid; high-energy/liquid) texture-nutrient combinations for nine subsequent meals, during which ad libitum intake was measured. Intake at first exposure did not differ between the low-energy (280±150kcal) and high-energy preloads (292±183kcal) in the incongruent conditions. By contrast, it was greater after the low-energy (332±203kcal) than after the high-energy (236±132kcal) preload in the congruent conditions (energy∗incongruent/congruent, p=0.04). Post-exposure, this pattern changed: intake depended on the energy density of the preloads in all conditions, and was greater after low-energy preloads (day∗energy∗incongruent/congruent-interaction for breakfast: p=0.02). Thus, manipulating the sensory properties of a food influenced energy compensation and meal size, but only at initial exposure. Repeated exposure 'corrected' the initial lack of compensation observed in conditions with incongruent sensory-nutrient pairings.

  11. Comparative systems toxicology analysis of cigarette smoke and aerosol from a candidate modified risk tobacco product in organotypic human gingival epithelial cultures: A 3-day repeated exposure study.

    Science.gov (United States)

    Zanetti, Filippo; Titz, Bjoern; Sewer, Alain; Lo Sasso, Giuseppe; Scotti, Elena; Schlage, Walter K; Mathis, Carole; Leroy, Patrice; Majeed, Shoaib; Torres, Laura Ortega; Keppler, Brian R; Elamin, Ashraf; Trivedi, Keyur; Guedj, Emmanuel; Martin, Florian; Frentzel, Stefan; Ivanov, Nikolai V; Peitsch, Manuel C; Hoeng, Julia

    2017-03-01

    Smoking is one of the major lifestyle-related risk factors for periodontal diseases. Modified risk tobacco products (MRTP) offer a promising alternative in the harm reduction strategy for adult smokers unable to quit. Using a systems toxicology approach, we investigated and compared the exposure effects of a reference cigarette (3R4F) and a heat-not-burn technology-based candidate MRTP, the Tobacco Heating System (THS) 2.2. Human gingival epithelial organotypic cultures were repeatedly exposed (3 days) for 28 min at two matching concentrations of cigarette smoke (CS) or THS2.2 aerosol. Results showed only minor histopathological alterations and minimal cytotoxicity upon THS2.2 aerosol exposure compared to CS (1% for THS2.2 aerosol vs. 30% for CS, at the high concentration). Among the 14 proinflammatory mediators analyzed, only 5 exhibited significant alterations with THS2.2 exposure compared with 11 upon CS exposure. Transcriptomic and metabolomic analysis indicated a general reduction of the impact in THS2.2 aerosol-exposed samples with respect to CS (∼79% lower biological impact for the high THS2.2 aerosol concentration compared to CS, and 13 metabolites significantly perturbed for THS2.2 vs. 181 for CS). This study indicates that exposure to THS2.2 aerosol had a lower impact on the pathophysiology of human gingival organotypic cultures than CS. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. Narrative exposure therapy for posttraumatic stress disorder associated with repeated interpersonal trauma in patients with severe mental illness: a mixed methods design

    Directory of Open Access Journals (Sweden)

    Maria W. Mauritz

    2016-09-01

    Full Text Available Background: In the Netherlands, most patients with severe mental illness (SMI receive flexible assertive community treatment (FACT provided by multidisciplinary community mental health teams. SMI patients with comorbid posttraumatic stress disorder (PTSD are sometimes offered evidence-based trauma-focused treatment like eye movement desensitization reprocessing or prolonged exposure. There is a large amount of evidence for the effectiveness of narrative exposure therapy (NET within various vulnerable patient groups with repeated interpersonal trauma. Some FACT-teams provide NET for patients with comorbid PTSD, which is promising, but has not been specifically studied in SMI patients. Objectives: The primary aim is to evaluate NET in SMI patients with comorbid PTSD associated with repeated interpersonal trauma to get insight into whether (1 PTSD and dissociative symptoms changes and (2 changes occur in the present SMI symptoms, care needs, quality of life, global functioning, and care consumption. The second aim is to gain insight into patients’ experiences with NET and to identify influencing factors on treatment results. Methods: This study will have a mixed methods convergent design consisting of quantitative repeated measures and qualitative semi-structured in-depth interviews based on Grounded Theory. The study population will include adult SMI outpatients (n=25 with comorbid PTSD and receiving NET. The quantitative study parameters will be existence and severity of PTSD, dissociative, and SMI symptoms; care needs; quality of life; global functioning; and care consumption. In a longitudinal analysis, outcomes will be analyzed using mixed models to estimate the difference in means between baseline and repeated measurements. The qualitative study parameters will be experiences with NET and perceived factors for success or failure. Integration of quantitative and qualitative results will be focused on interpreting how qualitative results

  13. Reactive Oxygen Species-mediated Loss of Phenotype of Parvalbumin Interneurons Contributes to Long-term Cognitive Impairments After Repeated Neonatal Ketamine Exposures.

    Science.gov (United States)

    Zhang, Hui; Sun, Xiao-Ru; Wang, Jing; Zhang, Zhen-Zhen; Zhao, Hong-Ting; Li, Hui-Hui; Ji, Mu-Huo; Li, Kuan-Yu; Yang, Jian-Jun

    2016-11-01

    Ketamine, a common anesthetic used for pediatric patients, has been shown to induce neurotoxicity and alter adolescent behaviors in rats when administered during neonatal period. However, the mechanisms underlying this kind of neurotoxicity remain largely to be determined. Herein, we studied whether the reactive oxygen species (ROS) due to the increased NOX2 mediates loss of phenotype of PV interneurons and thus contributes to long-term cognitive impairments after repeated ketamine exposures. Sprague-Dawley male rat pups received a daily administration of ketamine intraperitoneally (75 mg/kg) from postnatal day 6 (P6) to P8 for three consecutive days. For the interventional study, pups were treated with a NADPH oxidase inhibitor, apocynin (Apo). Learning and memory abilities were tested by the open field, fear conditioning, and Morris water maze on P40, P42-44, and P50-56, respectively. For histological and biochemical assays, a separate cohort of rats was killed on P9 or P60, and the brain tissues were harvested. Our results showed the upregulation of 8-OHdG and gp91/NOX2 and downregulation of PV and glutamic acid decarboxylase 67 (GAD67) after repeated ketamine exposures, which co-occurred with the long-term cognitive impairments as evidenced by the decreased freezing time to context. However, Apo treatment attenuated these abnormalities. Our results suggest that oxidative damage, probably due to the increased NOX2, mediates loss of phenotype of PV interneurons and thus contributes to long-term cognitive impairments after repeated ketamine exposures. Moreover, the inhibition of NADPH oxidase may protect against cognitive dysfunction.

  14. Ventilatory long-term facilitation is evident after initial and repeated exposure to intermittent hypoxia in mice genetically depleted of brain serotonin.

    Science.gov (United States)

    Hickner, Stephen; Hussain, Najaah; Angoa-Perez, Mariana; Francescutti, Dina M; Kuhn, Donald M; Mateika, Jason H

    2014-02-01

    Our study was designed to determine if central nervous system (CNS) serotonin is required for the induction of ventilatory long-term facilitation (LTF) in intact, spontaneously breathing mice. Nineteen tryptophan hydroxylase 2-deficient (Tph2(-/-)) mice, devoid of serotonin in the CNS, and their wild-type counterparts (Tph2(+/+)) were exposed to intermittent hypoxia each day for 10 consecutive days. The ventilatory response to intermittent hypoxia was greater in the Tph2(+/+) compared with the Tph2(-/-) mice (1.10 ± 0.10 vs. 0.77 ± 0.01 ml min(-1)·percent(-1) oxygen; P ≤ 0.04). Ventilatory LTF, caused by increases in breathing frequency, was evident in Tph2(+/+) and Tph2(-/-) mice following exposure to intermittent hypoxia each day; however, the magnitude of the response was greater in the Tph2(+/+) compared with the Tph2(-/-) mice (1.11 ± 0.02 vs. 1.05 ± 0.01 normalized to baseline on each day; P ≤ 0.01). The magnitude of ventilatory LTF increased significantly from the initial to the finals days of the protocol in the Tph2(-/-) (1.06 ± 0.02 vs. 1.11 ± 0.03 normalized to baseline on the initial days; P ≤ 0.004) but not in the Tph2(+/+) mice. This enhanced response was mediated by increases in tidal volume. Body temperature and metabolic rate did not account for differences in the magnitude of ventilatory LTF observed between groups after acute and repeated daily exposure to intermittent hypoxia. We conclude that ventilatory LTF, after acute exposure to intermittent hypoxia, is mediated by increases in breathing frequency and occurs in the absence of serotonin, although the magnitude of the response is diminished. This weakened response is enhanced following repeated daily exposure to intermittent hypoxia, via increases in tidal volume, to a similar magnitude evident in Tph2(+/+) mice. Thus the magnitude of ventilatory LTF following repeated daily exposure to intermittent hypoxia is not dependent on the presence of CNS serotonin.

  15. In utero exposure to nanosized carbon black (Printex90) does not induce tandem repeat mutations in female murine germ cells

    DEFF Research Database (Denmark)

    Boisen, Anne Mette Zenner; Shipley, Thomas; Jackson, Petra

    2013-01-01

    J mice were exposed four times during gestation by intratracheal instillation of 67μg/animal of nanosized carbon black Printex90 or vehicle (gestation days 7, 10, 15 and 18). Female offspring were raised to maturity and mated with unexposed CBA males. Expanded simple tandem repeat (ESTR) germline...... mutation rates in the resulting F2 generation were determined from full pedigrees (mother, father, offspring) of F1 female mice (178 CB-exposed and 258 control F2 offspring). ESTR mutation rates in CB-exposed F2 female offspring were not statistically different from those of F2 female control offspring....

  16. Enhanced hepatotoxicity induced by repeated exposure to polychlorinated biphenyls and 2,3,7,8-tetrachlorodibenzo-p-dioxin in combination in male rats

    Institute of Scientific and Technical Information of China (English)

    Yimei Wang; Chunfeng Lu; Zhiguo Sheng; Gang Liu; Ze Fu; Benzhan Zhu; Shuangqing Peng

    2011-01-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and polychlorinated biphenyls (PCBs) are among persistent polyhalogenated aromatic hydrocarbons that exist as complex mixtures in the environment worldwide. The present study was attempted to investigate the hepatotoxicity following repeated exposure to TCDD and PCBs in combination in male rats, and to reveal the involvement of potential mechanisms. Male Sprague-Dawley rats were exposed to TCDD (10 μg/kg) and Aroclor 1254 (10 mg/kg, a representative mixture of PCBs) alone or in combination by intragastric administration. After 12-day exposure, all treatments produced significant hepatotoxicity as characterized by changes of plasma biochemistry and histopathological changes. These effects were more prominent in the combined group. Furthermore, all treatments induced hepatic cytochrome P450 1A1 (CYP1A1) expression, and the maximal level of CYP1A1 expression was observed in the combined group, as in the case of the most severe hepatotoxicity evoked by the combined exposure.These findings indicated that the hepatotoxicity induced by TCDD and Aroclor 1254 might be ascribed to the high expression of hepatic CYP1A1. The present study demonstrates the enhanced hepatotoxicity after exposure to TCDD and PCBs in combination in rats.

  17. An integrated approach to biomonitoring exposure to styrene and styrene-(7,8)-oxide using a repeated measurements sampling design.

    Science.gov (United States)

    Fustinoni, S; Campo, L; Manini, P; Buratti, M; Waidyanatha, S; De Palma, G; Mutti, A; Foa, V; Colombi, A; Rappaport, S M

    2008-09-01

    The aim of this work was to investigate urinary analytes and haemoglobin and albumin adducts as biomarkers of exposure to airborne styrene (Sty) and styrene-(7,8)-oxide (StyOX) and to evaluate the influence of smoking habit and genetic polymorphism of metabolic enzymes GSTM1 and GSTT1 on these biomarkers. We obtained three or four air and urine samples from each exposed worker (eight reinforced plastics workers and 13 varnish workers), one air and urine samples from 22 control workers (automobile mechanics) and one blood sample from all subjects. Median levels of exposure to Sty and StyOX, respectively, were 18.2 mg m(-3) and 133 microg m(-3) for reinforced plastics workers, 3.4 mg m(-3) and 12 microg m(-3) for varnish workers, and <0.3 mg m(-3) and <5 microg m(-3) for controls. Urinary levels of styrene, mandelic acid, phenylglyoxylic acid, phenylglycine (PHG), 4-vinylphenol (VP) and mercapturic acids (M1+M2), as well as cysteinyl adducts of serum albumin (but not those of haemoglobin) were significantly associated with exposure status (controlsexposure, suggestive of saturable metabolism. Levels of the protein adducts were not associated with exposure to either Sty or StyOX among exposed subjects.

  18. Association between secondhand smoke exposure at home and cigarette gifting and sharing in Zhejiang, China: a repeat cross-sectional study.

    Science.gov (United States)

    Xu, Yue; Xu, ShuiYang; Wu, QingQing; Guo, YuJie

    2016-03-03

    The aims of the current study were to assess the prevalence of household cigarette gifting and sharing, and to evaluate the relationship between secondhand smoke (SHS) exposure, and cigarette gifting and sharing, in Zhejiang, China. A repeat cross-sectional design. 10 sites in 5 cities in Zhejiang, China. Two surveys were conducted with adults in Zhejiang, China, in 2010 (N=2112) and 2012 (N=2279), respectively. At both waves, the same questionnaire was used; respondents were asked questions on residence, number of family smokers, indoor smoking rules, household income and cigarette gifting and sharing. The findings revealed that more than half of respondents' families (54.50% in 2010, 52.79% in 2012) reported exposure to SHS. Many families (54.73% in 2010, 47.04% in 2012) shared cigarettes with others, and a minority (14.91% in 2010, 14.17% in 2012) reported their family giving cigarettes as a gift. There was a significant decrease in cigarette sharing from 2010 to 2012, irrespective of household with SHS exposure status; and the cigarette gifting was significantly decreased in household without SHS exposure. Compared to households without SHS exposure, the prevalence of cigarette gifting and sharing in households with SHS exposure was more obvious. Encouraging and promoting a smoke-free household environment is necessary to change public smoking customs in Zhejiang, China. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  19. Dexmedetomidine attenuates repeated propofol exposure-induced hippocampal apoptosis, PI3K/Akt/Gsk-3β signaling disruption, and juvenile cognitive deficits in neonatal rats.

    Science.gov (United States)

    Wang, Yujie; Wu, Changyi; Han, Bin; Xu, Fei; Mao, Mingfeng; Guo, Xiangyang; Wang, Jun

    2016-07-01

    Propofol is one of the most widely used intravenous anesthetics. However, repeated exposure to propofol may cause neurodegeneration in the developing brain. Dexmedetomidine (Dex), an α2 adrenoceptor agonist, has been previously demonstrated to provide neuroprotection against neuroapoptosis and neurocognitive impairments induced by several anesthetics. Thus, the current study aimed to investigate the effect of Dex on neonatal propofol-induced neuroapoptosis and juvenile spatial learning/memory deficits. Propofol (30 mg/kg) was intraperiotoneally administered to 7‑day‑old Sprague Dawley rats (n=75) three times each day at 90 min intervals for seven consecutive days with or without Dex (75 µg/kg) treatment 20 min prior to propofol injection. Following repeated propofol exposure, reduced Akt and GSK‑3β phosphorylation, increased cleaved caspase‑3 expression levels, an increased Bax/Bcl‑2 ratio, and increased terminal deoxynucleotidyl transferase‑mediated dUTP nick‑end labeling (TUNEL)‑positive cells in the CA1 hippocampal subregion were observed. Morris Water Maze testing at postnatal day 29 also demonstrated spatial learning and memory deficits following propofol treatment compared with the control group. Notably, these changes were significantly attenuated by Dex pretreatment. The results of the current study demonstrated that Dex ameliorates the neurocognitive impairment induced by repeated neonatal propofol challenge in rats, partially via its anti‑apoptotic action and normalization of the disruption to the PI3K/Akt/GSK‑3β signaling pathway. The present study provides preliminary evidence demonstrating the safety of propofol on the neonatal brain and the potential use of dexmedetomidine pretreatment in pediatric patients.

  20. Eosinophilia and biotoxin exposure in bottlenose dolphins (Tursiops truncatus) from a coastal area impacted by repeated mortality events

    Energy Technology Data Exchange (ETDEWEB)

    Schwacke, Lori H., E-mail: Lori.Schwacke@noaa.gov [National Oceanic and Atmospheric Administration, National Ocean Service, Center for Human Health Risks, 331 Fort Johnson Road, Charleston, SC 29412 (United States); Twiner, Michael J. [National Oceanic and Atmospheric Administration, National Ocean Service, Center for Coastal Environmental Health and Biomolecular Research, 219 Fort Johnson Road, Charleston, SC 29412 (United States); De Guise, Sylvain [University of Connecticut, Department of Pathobiology and Veterinary Science, 61 North Eagleville Road, U-89, Storrs, CT 06269 (United States); Balmer, Brian C.; Wells, Randall S. [Chicago Zoological Society, c/o Mote Marine Laboratory, 1600 Ken Thompson Parkway, Sarasota, FL 34236 (United States); Townsend, Forrest I. [Bayside Hospital for Animals, 251 N.E. Racetrack Road, Fort Walton Beach, FL 32547 (United States); Rotstein, David C. [National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Office of Protected Resources, Marine Mammal Health and Stranding Response Program, 1315 East West Highway, Silver Spring, MD 20910 (United States); Varela, Rene A. [Ocean Embassy Inc, 6433 Pinecastle Blvd, Ste 2, Orlando, FL 32809 (United States); Hansen, Larry J. [National Oceanic and Atmospheric Administration, National Marine Fisheries Service Southeast Fisheries Science Center,101 Pivers Island Road, Beaufort, NC 28516 (United States); Zolman, Eric S. [National Oceanic and Atmospheric Administration, National Ocean Service, Center for Coastal Environmental Health and Biomolecular Research, 219 Fort Johnson Road, Charleston, SC 29412 (United States); Spradlin, Trevor R. [National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Office of Protected Resources, Marine Mammal Health and Stranding Response Program, 1315 East West Highway, Silver Spring, MD 20910 (United States); and others

    2010-08-15

    Bottlenose dolphins (Tursiops truncatus) inhabiting coastal waters in the northern Gulf of Mexico have been impacted by recurrent unusual mortality events over the past few decades. Several of these mortality events along the Florida panhandle have been tentatively attributed to poisoning from brevetoxin produced by the dinoflagellate Karenia brevis. While dolphins in other regions of the Florida coast are often exposed to K. brevis blooms, large-scale dolphin mortality events are relatively rare and the frequency and magnitude of die-offs along the Panhandle raise concern for the apparent vulnerability of dolphins in this region. We report results from dolphin health assessments conducted near St. Joseph Bay, Florida, an area impacted by 3 unusual die-offs within a 7-year time span. An eosinophilia syndrome, manifested as an elevated blood eosinophil count without obvious cause, was observed in 23% of sampled dolphins. Elevated eosinophil counts were associated with decreased T-lymphocyte proliferation and increased neutrophil phagocytosis. In addition, indication of chronic low-level exposure to another algal toxin, domoic acid produced by the diatom Pseudo-nitzschia spp., was determined. Previous studies of other marine mammal populations exposed recurrently to Pseudo-nitzschia blooms have suggested a possible link between the eosinophilia and domoic acid exposure. While the chronic eosinophilia syndrome could over the long-term produce organ damage and alter immunological status and thereby increase vulnerability to other challenges, the significance of the high prevalence of the syndrome to the observed mortality events in the St. Joseph Bay area is unclear. Nonetheless, the unusual immunological findings and concurrent evidence of domoic acid exposure in this sentinel marine species suggest a need for further investigation to elucidate potential links between chronic, low-level exposure to algal toxins and immune health.

  1. Effects of repeated prenatal glucocorticoid exposure on long-term potentiation in the juvenile guinea-pig hippocampus.

    Science.gov (United States)

    Setiawan, Elaine; Jackson, Michael F; MacDonald, John F; Matthews, Stephen G

    2007-06-15

    Synthetic glucocorticoids (sGCs) are routinely used to treat women at risk of preterm labour to promote fetal lung maturation. There is now strong evidence that exposure to excess glucocorticoid during periods of rapid brain development has permanent consequences for endocrine function and behaviour in the offspring. Prenatal exposure to sGC alters the expression of N-methyl-D-aspartate receptor (NMDA-R) subunits in the fetal and neonatal hippocampus. Given the integral role of the NMDA-R in synaptic plasticity, we hypothesized that prenatal sGC exposure will have effects on hippocampal long-term potentiation (LTP) after birth. Further, this may occur in either the presence or absence of elevated cortisol concentrations, in vitro. Pregnant guinea-pigs were injected with betamethasone (Beta, 1 mg kg(-1)) or vehicle on gestational days (gd) 40, 41, 50, 51, 60 and 61 (term approximately 70 days), a regimen comparable to that given to pregnant women. On postnatal day 21, LTP was examined at Schaffer collateral synapses in the CA1 region of hippocampal slices prepared from juvenile animals exposed to betamethasone or vehicle, in utero. Subsequently, the acute glucocorticoid receptor (GR)- and mineralocorticoid receptor (MR)-dependent effects of cortisol (0.1-10 microM; bath applied 30 min before LTP induction) were examined. There was no effect of prenatal sGC treatment on LTP under basal conditions. The application of 10 microM cortisol depressed excitatory synaptic transmission in all treatment groups regardless of sex. Similarly, LTP was depressed by 10 microM cortisol in all groups, with the exception of Beta-exposed females, in which LTP was unaltered. Hippocampal MR and GR protein levels were increased in Beta-exposed females, but not in any other prenatal treatment group. This study reveals sex-specific effects of prenatal exposure to sGC on LTP in the presence of elevated cortisol, a situation that would occur in vivo during stress.

  2. Repeated exposure of adolescent rats to oral methylphenidate does not induce behavioral sensitization or cross-sensitization to nicotine

    Directory of Open Access Journals (Sweden)

    C.C. Justo

    2010-07-01

    Full Text Available Several lines of evidence indicate that the use of stimulant drugs, including methylphenidate (MPD, increases tobacco smoking. This has raised concerns that MPD use during adolescence could facilitate nicotine abuse. Preclinical studies have shown that repeated treatment with an addictive drug produces sensitization to that drug and usually cross-sensitization to other drugs. Behavioral sensitization has been implicated in the development of drug addiction. We examined whether repeated oral MPD administration during adolescence could induce behavioral sensitization to MPD and long-lasting cross-sensitization to nicotine. Adolescent male Wistar rats were treated orally with 10 mg/kg MPD or saline (SAL from postnatal day (PND 27 to 33. To evaluate behavioral sensitization to MPD in adolescent rats (PND 39, the SAL pretreated group was subdivided into two groups that received intragastric SAL (1.0 mL/kg or MPD (10 mg/kg; MPD pretreated rats received MPD (10 mg/kg. Cross-sensitization was evaluated on PND 39 or PND 70 (adulthood. To this end, SAL- and MPD-pretreated groups received subcutaneous injections of SAL (1.0 mL/kg or nicotine (0.4 mg/kg. All groups had 8 animals. Immediately after injections, locomotor activity was determined. The locomotor response to MPD challenge of MPD-pretreated rats was not significantly different from that of the SAL-pretreated group. Moreover, the locomotor response of MPD-pretreated rats to nicotine challenge was not significantly different from that of the SAL-pretreated group. This lack of sensitization and cross-sensitization suggests that MPD treatment during adolescence does not induce short- or long-term neuroadaptation in rats that could increase sensitivity to MPD or nicotine.

  3. Decreased extracellular adenosine levels lead to loss of hypoxia-induced neuroprotection after repeated episodes of exposure to hypoxia.

    Directory of Open Access Journals (Sweden)

    Mei Cui

    Full Text Available Achieving a prolonged neuroprotective state following transient ischemic attacks (TIAs is likely to effectively reduce the brain damage and neurological dysfunction associated with recurrent stroke. HPC is a phenomenon in which advanced exposure to mild hypoxia reduces the stroke volume produced by a subsequent TIA. However, this neuroprotection is not long-lasting, with the effects reaching a peak after 3 days. Therefore, in this study, we investigated the use of multiple episodes of hypoxic exposure at different time intervals to induce longer-term protection in a mouse stroke model. C57BL/6 mice were subjected to different hypoxic preconditioning protocols: a single episode of HPC or five identical episodes at intervals of 3 days (E3d HPC or 6 days (E6d HPC. Three days after the last hypoxic exposure, temporary middle cerebral artery occlusion (MCAO was induced. The effects of these HPC protocols on hypoxia-inducible factor (HIF regulated gene mRNA expression were measured by quantitative PCR. Changes in extracellular adenosine concentrations, known to exert neuroprotective effects, were also measured using in vivo microdialysis and high pressure liquid chromatography (HPLC. Neuroprotection was provided by E6d HPC but not E3d HPC. HIF-regulated target gene expression increased significantly following all HPC protocols. However, E3d HPC significantly decreased extracellular adenosine and reduced cerebral blood flow in the ischemic region with upregulated expression of the adenosine transporter, equilibrative nucleoside transporter 1 (ENT1. An ENT1 inhibitor, propentofylline increased the cerebral blood flow and re-established neuroprotection in E3d HPC. Adenosine receptor specific antagonists showed that adenosine mainly through A1 receptor mediates HPC induced neuroprotection. Our data indicate that cooperation of HIF-regulated genes and extracellular adenosine is necessary for HPC-induced neuroprotection.

  4. Prevention of diabetes in NOD mice by repeated exposures to a contact allergen inducing a sub-clinical dermatitis

    DEFF Research Database (Denmark)

    Engkilde, Kaare; Buschard, Karsten; Hansen, Axel Jacob Kornerup

    2010-01-01

    Type 1 diabetes is an autoimmune disease, while allergic contact dermatitis although immune mediated, is considered an exposure driven disease that develops due to epicutaneous contact with reactive low-molecular chemicals. The objective of the present study was to experimentally study the effect...... of contact allergens on the development of diabetes in NOD mice. As the link between contact allergy and diabetes is yet unexplained we also examined the effect of provocation with allergens on Natural Killer T (NKT) cells, since involvement of NKT cells could suggest an innate connection between the two...

  5. Mechanisms of adaptation from a multiple to a single step recovery strategy following repeated exposure to forward loss of balance in older adults.

    Directory of Open Access Journals (Sweden)

    Christopher P Carty

    Full Text Available When released from an initial, static, forward lean angle and instructed to recover with a single step, some older adults are able to meet the task requirements, whereas others either stumble or fall. The purpose of the present study was to use the concept of margin of stability (MoS to investigate balance recovery responses in the anterior-posterior direction exhibited by older single steppers, multiple steppers and those that are able to adapt from multiple to single steps following exposure to repeated forward loss of balance. One hundred and fifty-one healthy, community dwelling, older adults, aged 65-80 years, participated in the study. Participants performed four trials of the balance recovery task from each of three initial lean angles. Balance recovery responses in the anterior-posterior direction were quantified at three events; cable release (CR, toe-off (TO and foot contact (FC, for trials performed at the intermediate lean angle. MoS was computed as the anterior-posterior distance between the forward boundary of the Base of Support (BoS and the vertical projection of the velocity adjusted centre of mass position (XCoM. Approximately one-third of participants adapted from a multiple to a single step recovery strategy following repeated exposure to the task. MoS at FC for the single and multiple step trials in the adaptation group were intermediate between the exclusively single step group and the exclusively multiple step group, with the single step trials having a significant, 3.7 times higher MoS at FC than the multiple step trials. Consistent with differences between single and multiple steppers, adaptation from multiple to single steps was attributed to an increased BoS at FC, a reduced XCoM at FC and an increased rate of BoS displacement from TO to FC. Adaptations occurred within a single test session and suggest older adults that are close to the threshold of successful recovery can rapidly improve dynamic stability following

  6. Acute Onset of Vancomycin Anaphylaxis With Disseminated Intravascular Coagulation in an Orthopedic Patient Despite Prior Repeated Exposure.

    Science.gov (United States)

    Adams, Brock; Roboubi, Babak; Henshaw, Robert

    2015-12-01

    Vancomycin is a glycopeptide antibiotic that exhibits bactericidal activity against gram-positive cocci. It is commonly recommended for surgical prophylaxis in cases of suspected bacterial resistance or penicillin allergy. There are 2 main types of hypersensitivity reactions associated with vancomycin. Red man syndrome is an anaphylactoid reaction caused by direct release of histamine. The second is an anaphylactic reaction, which is an immunoglobulin E-mediated response. We present the case of a 55-year-old woman with a history of metastatic giant cell tumor of the right proximal tibia. She had undergone multiple surgeries for this and other nonorthopedic conditions. The patient received vancomycin for the majority of these procedures and extended courses of vancomycin on 2 separate occasions. In the present case, the patient was taken to the operating room for a prosthetic infection, and vancomycin was given after cultures were taken. The patient immediately developed signs consistent with anaphylaxis and disseminated intravascular coagulation. This was treated acutely with hemodynamic resuscitation, replacement of blood components, steroids, and repeated boluses of epinephrine. She recovered and was taken back to the operating room during that same admission without incident. The patient has since been treated with systemic daptomycin and a tobramycin cement spacer without further incident.

  7. Repeated sedimentation and exposure of glacial Lake Missoula sediments: A lake-level history at Garden Gulch, Montana, USA

    Science.gov (United States)

    Smith, Larry N.

    2017-01-01

    Glaciolacustrine sediments record lake transgression, regression, and subaerial modification of the silty lake-bottom of glacial Lake Missoula in the Clark Fork River valley. The sequence preserved at Garden Gulch, MT documents lake-level fluctuations at >65% of its full-pool volume. Twelve sedimentary cycles fine upwards from (1) very fine-grained sandy silt to (2) silt with climbing ripples to (3) rhythmically laminated silt and some clay. The cycles are fine-grained turbidites capped locally by thin layers of angular gravel derived from local bedrock outcrops. The gravels appear to be the toes of mass wasting lobes carried onto the exposed lakebed surface during repeated lake-level lowerings. Periglacial wedges, small rotational faults, involutions, and clastic dikes deform the tops of eleven cycles. The wedges are 10-30 cm wide, penetrate 30-70 cm deep, are spaced seven cycles. The Garden Gulch section may represent as few as seven and as many as twelve substantial fillings and partial to complete drainings of glacial Lake Missoula.

  8. Repeated inhalation exposure to octamethylcyclotetrasiloxane produces hepatomegaly, transient hepatic hyperplasia, and sustained hypertrophy in female Fischer 344 rats in a manner similar to phenobarbital.

    Science.gov (United States)

    McKim, J M; Kolesar, G B; Jean, P A; Meeker, L S; Wilga, P C; Schoonhoven, R; Swenberg, J A; Goodman, J I; Gallavan, R H; Meeks, R G

    2001-04-15

    Octamethylcyclotetrasiloxane (D4) has been described as a phenobarbital-like inducer of hepatic enzymes. Phenobarbital (PB) and phenobarbital-like chemicals induce transient hepatic and thyroid hyperplasia and sustained hypertrophy in rats and mice. The extent to which these processes are involved with D4-induced hepatomegaly is not known. The present study has evaluated the effects of repeated inhalation exposure to D4 vapors on hepatic and thyroid cell proliferation and hypertrophy with respect to time and exposure concentration. Female Fischer 344 rats were exposed via whole body inhalation to 0 ppm D4, 700 ppm D4 vapors (6 h/day; 5 days/week), or 0.05% PB in drinking water over a 4-week period. Incorporation of 5'-bromo-2-deoxyuridine (BrdU) and the abundance of proliferating cell nuclear antigen were used as indicators of cell proliferation. Designated animals from each treatment group were euthanized on study days 6, 13, and 27. The effect of D4 exposure concentration on hepatic cell proliferation was evaluated at 0, 7, 30, 70, 150, 300, or 700 ppm. Liver-to-body weight ratios in animals exposed to 700 ppm D4 were increased 18, 20, and 22% over controls while PB-treated animals showed increases of 33, 27, and 27% over controls on days 6, 13, and 27 respectively. Hepatic incorporation of BrdU following exposure to D4 was highest on day 6 (labeling index = 15-22%) and was at or below control values by day 27. This pattern of transient hyperplasia was observed in all hepatic lobes examined and was similar to the pattern observed following treatment with PB.

  9. Disposition of Lead (Pb) in Saliva and Blood of Sprague-Dawley Rats Following a Single or Repeated Oral Exposure to Pb-Acetate

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    Timchalk, Chuck; Lin, Yuehe; Weitz, Karl K.; Wu, Hong; Gies, Richard A.; Moore, Dean A.; Yantasee, Wassana

    2006-05-01

    Biological monitoring for lead (Pb) is usually based upon a determination of blood Pb concentration; however, saliva has been suggested as a non-invasive biological matrix for assessing exposure. To further evaluate the potential utility of saliva for biomonitoring, the disposition of Pb was evaluated in whole blood (WB), red blood cells (RBC), plasma, parotid gland, bone, and saliva following either a single oral dose of 100 mg Pb-acetate/kg body weight in rats or {approx}1-week after 5 sequential daily oral gavage doses of 1, 10, or 100 mg Pb-acetate/kg/day. Saliva volume, pH, total saliva protein, and ?-amylase activity were also determined. At specified times post-dosing groups of animals were anethetized and administered pilocarpine to induce salivation. Saliva was collected, the animals were humanely sacrificed, and tissue samples were likewise collected, weighed, and processed for Pb analysis. Following a single dose exposure to PB-acetate, Pb was detectable in all samples by 30 min post-dosing. For both the single and repeated dose treatments the concentration of Pb was highest in WB and RBC relative to plasma and saliva. However, the Pb rapidly redistributed (within 5-days post-treatment) from the blood into the bone compartment based on the substantial decrease in WB and RBC Pb concentration, and the concurrent increase in bone Pb following repeated exposure at all dose levels. Although there is clear variability in the observed Pb concentrations in plasma and saliva, there was a reasonable correlation (r2=0.922) between the average Pb concentrations in these biological matrices which was consistent with previous observations. The single oral dose of Pb-acetate resulted in a decrease in salivary pH which recovered by 24 hr post-dosing and a decrease in ?-amylase enzyme activity which did recover within 5-days of ceasing exposure. It is currently unclear what impact these slight functional changes may or may not have on Pb salivary clearance rates. These

  10. Development of immunity against viral and bacterial antigens after repeated exposures to suberythemal doses of ultraviolet light

    Directory of Open Access Journals (Sweden)

    S. A. Snopov

    2012-01-01

    Full Text Available The effects of ultraviolet (UV radiation on human infectious immunity are not well studied. On the one hand, solar and artificial UU sources have been shown to change cytokine levels in human skin, lymphocyte subpopulation counts in parepheral blood, lymphocyte DNA synthesis and prolifarative response to mitogens. On the other hand, there are just only one or two observations suggesting an influence of UV radiation on human infection course. For instance, UV irradiations have been reported to induce a reccurence of orofacial vesicular lesions caused by herpes siplex virus. Moreover, there is a lack of data concerning immune effects of suberythtemal doses of UV in spite of a long history of using them by Russian prophylactic medicine. In this work we questioned whether such suberythemal UV exposures can affect the immune responses of children to infectious conjunctivitis, to simultaneous measles and polio vaccinations and to simultaneous polio and diphtheria-tetanus vaccinations. In peripheral blood of vaccinated children we examined leukocyte counts (monocytes, neutrophils, eosinophils, lymphocytes, percentages of lymphocyte subpopulations (CD3+, CD20+, CD4+, CD8+, CD25+, HLADR+, concentrations of cytokines (IL-1 beta, TNF-alpha, IFN- amma и IL-10, DNA-synthetic activity of lymphocytes and titres of antibodies against measles and diphtheria toxin. We observed no local or systemic reactions to the vaccines in the UV-group while a moderate rise in body temperature occured in several children from unexposed group. In the blood of childeren from UV-group we found increases in CD25+ и HLADR+ cell percentages, IL- 1 beta and IL-10 concentrations, PWMinduced DNA synthesis in mononuclears, and no decreases in formation of antibodies against measles and diphreria. We concluded that suberythemal UV exposures of children modulated their further responses to imminisations perhaps through the activation of a T helper 2-like

  11. Greater sensitivity to novelty in rats is associated with increased motor impulsivity following repeated exposure to a stimulating environment: implications for the etiology of impulse control deficits.

    Science.gov (United States)

    Ferland, Jacqueline-Marie N; Zeeb, Fiona D; Yu, Katrina; Kaur, Sukhbir; Taves, Matthew D; Winstanley, Catharine A

    2014-12-01

    Heightened motor impulsivity and increased novelty-seeking commonly co-occur in psychiatric disorders, including drug addiction. However, the relationship between these two phenomena remains unclear. One-time tests of novelty sensitivity commonly used in preclinical experiments, such as the open-field or novel-object test, fail to capture the fact that novelty-seekers repeatedly experience novel, stimulating situations. The present study therefore investigated whether repeated exposure to a novel, stimulating environment (SE) altered impulsive action. Male Long-Evans rats were trained to perform the five-choice serial reaction time task (5CSRTT) which measures motor impulsivity in the form of premature responding as well as attention and motivation. Animals were then exposed to a novel SE (1 h/day for 16 days) immediately prior to the 5CSRTT. Significant increases in premature responding were observed in a subgroup of reactive animals termed high responders (HR-SE). These rats were not more impulsive at baseline, and levels of impulsivity normalised once exposure to the SE was discontinued. No other aspect of 5CSRTT performance was affected by the SE challenge. We also determined that HR-SE rats were hyperactive in a novel environment. Biochemical analyses revealed changes in gene and protein expression within the dorsal hippocampus of HR-SE rats, including decreases in mRNA encoding the dopamine D1 receptor and brain-derived neurotrophic factor. These results indicate a novel mechanism by which impulsivity and novelty-reactivity interact that may enhance addiction vulnerability synergistically. Furthermore, studying such context-induced impulsivity may provide insight into the process by which environmental load precipitates psychiatric symptoms in impulse control disorders.

  12. Effects of repeated low-dose exposure of the nerve agent VX on monoamine levels in different brain structures in mice.

    Science.gov (United States)

    Graziani, S; Christin, D; Daulon, S; Breton, P; Perrier, N; Taysse, L

    2014-05-01

    In a previous report, alterations of the serotonin metabolism were previously reported in mice intoxicated with repeated low doses of soman. In order to better understand the effects induced by repeated low-dose exposure to organophosphorus compounds on physiological and behavioural functions, the levels of endogenous monoamines (serotonin and dopamine) in different brain areas in mice intoxicated with sublethal dose of (O-ethyl-S-[2(di-isopropylamino) ethyl] methyl phosphonothioate) (VX) were analysed by HPLC method with electrochemical detection. Animals were injected once a day for three consecutive days with 0.10 LD50 of VX (5 μg/kg, i.p). Neither severe signs of cholinergic toxicity nor pathological changes in brain tissue of exposed animals were observed. Cholinesterase (ChE) activity was only inhibited in plasma (a maximum of 30% inhibition 24 h after the last injection of VX), but remained unchanged in the brain. Serotonin and dopamine (DA) metabolism appeared significantly modified. During the entire period of investigation, at least one of the three parameters investigated (i.e. DA and DOPAC levels and DOPAC/DA ratio) was modified. During the toxic challenge, an increase of the serotonin metabolism was noted in hippocampus (HPC), hypothalamus/thalamus, pons medulla and cerebellum (CER). This increase was maintained 4 weeks after exposure in HPC, pons medulla and CER whereas a decrease in cortex 3 weeks after the toxic challenge was observed. The lack of correlation between brain ChE activity and neurochemical outcomes points out to independent mechanisms. The involvement in possibly long-lasting behavioural disorders is discussed.

  13. Biochemical and histopathological changes in the kidney and adrenal gland of rats following repeated exposure to lambda-cyhalothrin

    Directory of Open Access Journals (Sweden)

    Hassina Khaldoun Oularbi

    2014-04-01

    Full Text Available Lambda-cyhalothrin (LCT is a type II pyrethroid insecticide widely used in pest management. This study was undertaken to evaluate the toxic effects of LCT on the kidneys and adrenal glands of rats after subacute exposure. Twenty-eight 6-week-old male albino Rattus norvegicus rats were randomly assigned to four groups. Group 1 was the control group, which received distilled water. The experimental groups 2, 3 and 4 received 20.4, 30.6 and 61.2 mg/kg body weight, respectively, of LCT, administered orally over 28 days. The effects of the insecticide on various biochemical parameters were evaluated at 14 and 28 days. Histopathological studies were carried out in the kidneys and adrenal glands at the end of the experiment. Lambda-cyhalothrin, as a pyrethroid insecticide, induced significant increases (P≤0.05 in plasma urea, creatinine, uric acid and glucose concentrations, and alanine aminotransferase and aspartate aminotransferase activities after 14 and 28 days. In the rat plasma samples after 28 days, residual concentrations of LCT 1R, cis,

  14. Bed rest during pregnancy

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/patientinstructions/000581.htm Bed rest during pregnancy To use the sharing features on ... few days or weeks. This is called bed rest. Bed rest used to be recommended routinely for ...

  15. INFLUENCE OF MORINGA OLEIFERA (DRUM-STICK FRUIT EXTRACT ON HAEMATOLOGICAL PROFILE FOLLOWING REPEATED EXPOSURE TO LOW LEVELS OF ARSENIC THROUGH FEED ON RATS

    Directory of Open Access Journals (Sweden)

    Vaibhav R. Pachade

    2012-01-01

    Full Text Available Effect of Moringa oleifera fruits hot methanolic extract (MFE, if any, in minimizing the adverse reactions of repeated exposure to arsenic trioxide (AT in feed was investigated in Wistar rats with reference to haematological profile. Three groups of rats each containing 10 (5male+5female were used. The group I served as negative control. Rats of group II were fed arsenic trioxide (AT alone @ 100 ppm in feed while those of group III simultaneously received AT (@100 ppm and MFE (50 mg/kg/day for 28 days. Blood samples were collected from retroorbital plexus for estimation of hematological parameters (haemoglobin, PCV, TEC, MCH, MCHC, MCV of different groups on 0 day, 15th day and 29th day respectively. Exposure to AT through feed in group II resulted in significant (P<0.05 decrease in haemoglobin, TEC and MCHC, accompanied by increased MCV, with no significant alteration of PCV or MCH of the rats. While rats of group III treated with AT (@100 ppm and MFE (50 mg/kg/day also resulted in same consequences as it was in group II but it was slightly less than that of group II suggesting of mild non significant protective effect.

  16. Repeated PM2.5 exposure inhibits BEAS-2B cell P53 expression through ROS-Akt-DNMT3B pathway-mediated promoter hypermethylation.

    Science.gov (United States)

    Zhou, Wei; Tian, Dongdong; He, Jun; Wang, Yimei; Zhang, Lijun; Cui, Lan; Jia, Li; Zhang, Li; Li, Lizhong; Shu, Yulei; Yu, Shouzhong; Zhao, Jun; Yuan, Xiaoyan; Peng, Shuangqing

    2016-04-12

    Long-term exposure to fine particulate matter (PM2.5) has been reported to be closely associated with the increased lung cancer risk in populations, but the mechanisms underlying PM-associated carcinogenesis are not yet clear. Previous studies have indicated that aberrant epigenetic alterations, such as genome-wide DNA hypomethylation and gene-specific DNA hypermethylation contribute to lung carcinogenesis. And silence or mutation of P53 tumor suppressor gene is the most prevalent oncogenic driver in lung cancer development. To explore the effects of PM2.5 on global and P53 promoter methylation changes and the mechanisms involved, we exposed human bronchial epithelial cells (BEAS-2B) to low concentrations of PM2.5 for 10 days. Our results indicated that PM2.5-induced global DNA hypomethylation was accompanied by reduced DNMT1 expression. PM2.5 also induced hypermethylation of P53 promoter and inhibited its expression by increasing DNMT3B protein level. Furthermore, ROS-induced activation of Akt was involved in PM2.5-induced increase in DNMT3B. In conclusion, our results strongly suggest that repeated exposure to PM2.5 induces epigenetic silencing of P53 through ROS-Akt-DNMT3B pathway-mediated promoter hypermethylation, which not only provides a possible explanation for PM-induced lung cancer, but also may help to identify specific interventions to prevent PM-induced lung carcinogenesis.

  17. Influence of mercury exposure on blood pressure, resting heart rate and heart rate variability in French Polynesians: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Valera Beatriz

    2011-11-01

    Full Text Available Abstract Background Populations which diet is rich in seafood are highly exposed to contaminants such as mercury, which could affect cardiovascular risk factors Objective To assess the associations between mercury and blood pressure (BP, resting heart rate (HR and HR variability (HRV among French Polynesians Methods Data were collected among 180 adults (≥ 18 years and 101 teenagers (12-17 years. HRV was measured using a two-hour ambulatory electrocardiogram (Holter and BP was measured using a standardized protocol. The association between mercury and HRV and BP parameters was studied using analysis of variance (ANOVA and analysis of covariance (ANCOVA Results Among teenagers, the high frequency (HF decreased between the 2nd and 3rd tertile (380 vs. 204 ms2, p = 0.03 and a similar pattern was observed for the square root of the mean squared differences of successive R-R intervals (rMSSD (43 vs. 30 ms, p = 0.005 after adjusting for confounders. In addition, the ratio low/high frequency (LF/HF increased between the 2nd and 3rd tertile (2.3 vs. 3.0, p = 0.04. Among adults, the standard deviation of R-R intervals (SDNN tended to decrease between the 1st and 2nd tertile (84 vs. 75 ms, p = 0.069 after adjusting for confounders. Furthermore, diastolic BP tended to increase between the 2nd and 3rd tertile (86 vs. 91 mm Hg, p = 0.09. No significant difference was observed in resting HR or pulse pressure (PP Conclusions Mercury was associated with decreased HRV among French Polynesian teenagers while no significant association was observed with resting HR, BP, or PP among teenagers or adults

  18. Pulmonary responses in current smokers and ex-smokers following a two hour exposure at rest to clean air and fine ambient air particles.

    Science.gov (United States)

    BACKGROUND: Increased susceptibility of smokers to ambient PM may potentially promote development of COPD and accelerate already present disease. OBJECTIVES: To characterize the acute and subacute lung function response and inflammatory effects of controlled chamber exposure t...

  19. Repeated inhalation exposure of rats to an anionic high molecular weight polymer aerosol: application of prediction models to better understand pulmonary effects and modes of action.

    Science.gov (United States)

    Pauluhn, Jürgen

    2014-08-01

    Opposed to the wealth of information available for kinetic lung overload-related effects of poorly-soluble, low-toxicity particles (PSP), only limited information is available on biodegradable high molecular weight (HMW) organic polymers (molecular weight >20,000 Da). It is hypothesized that such types of polymers may exert a somewhat similar volume displacement-related mode of action in alveolar macrophages as PSP; however, with a differing biokinetics of the material retained in the lung. This polyurethane polymer was examined in single and 2-/13-week repeated exposure rat inhalation bioassays. The design of studies was adapted to that commonly applied for PSP. Rats were nose-only exposed for 6h/day for the respective study duration, followed by 1-, 2- and 4-week postexposure periods in the single, 2- and 13-week studies, respectively. While the findings in bronchoalveolar lavage (BAL) and histopathology were consistent with those typical of PSP, they appear to be superimposed by pulmonary phospholipidosis and a much faster reversibility of pulmonary inflammation. Kinetic modeling designed to estimate the accumulated lung burden of biopersistent PSP was also suitable to simulate the overload-dependent outcomes of this biodegradable polymer as long as the faster than normal elimination kinetics was observed and an additional 'void space volume' was added to adjust for the phagocytosed additional fraction of pulmonary phospholipids. The changes observed following repeated inhalation exposure appear to be consistent with a retention-related etiopathology (kinetic overload). In summary, this study did not reveal evidence of any polymer-specific pulmonary irritation or parenchymal injury. Taking all findings into account, 7 mg polymer/m(3) (exposure 6h/day, 5-days/week on 13 consecutive weeks) constitutes the point of departure for lower respiratory tract findings that represent a transitional state from effects attributable to an overload-dependent pulmonary

  20. Effects of repeated whole-body cold exposures on serum concentrations of growth hormone, thyrotropin, prolactin and thyroid hormones in healthy women.

    Science.gov (United States)

    Smolander, Juhani; Leppäluoto, Juhani; Westerlund, Tarja; Oksa, Juha; Dugue, Benoit; Mikkelsson, Marja; Ruokonen, Aimo

    2009-06-01

    Cold therapy is used to relieve pain and inflammatory symptoms. Humoral changes may account for the pain alleviation related to the cold exposures. The aim of the present study was to examine the effects of two types of cold therapy, winter swimming in ice-cold water (WS) and whole body cryotherapy (WBC), on the serum levels of the growth hormone, prolactin, thyrotropin and free fractions of thyroid hormones (fT3, fT4). One group of healthy females (n = 6) was exposed to WS (water 0-2 degrees C) for 20 s and another group (n = 6) to WBC (air 110 degrees C) for 2 min, three times a week for 12 weeks. Blood samples used for the hormone measurements were taken on weeks 1, 4 and 12 before and 35 min after the cold exposures and on the days of the respective weeks, when the cold exposures were not performed. During the WS treatments, serum thyrotropin increased significantly at 35 min on weeks 1 (p < 0.01) and 4 (p < 0.05), but the responses were within the health-related reference interval. During the WS, the serum prolactin measured at 35 min on week 12 was lower than during the control treatment, and no changes in fT3 or fT4 were observed. During the WBC, no changes in the serum levels of the studied hormones were observed during the 12 weeks. In conclusion, repeated WS and WBC treatments for healthy females do not lead to disorders related to altered secretions of the growth hormone, prolactin, thyrotropin, or thyroid hormones.

  1. REST based mobile applications

    Science.gov (United States)

    Rambow, Mark; Preuss, Thomas; Berdux, Jörg; Conrad, Marc

    2008-02-01

    Simplicity is the major advantage of REST based webservices. Whereas SOAP is widespread in complex, security sensitive business-to-business aplications, REST is widely used for mashups and end-user centric applicatons. In that context we give an overview of REST and compare it to SOAP. Furthermore we apply the GeoDrawing application as an example for REST based mobile applications and emphasize on pros and cons for the use of REST in mobile application scenarios.

  2. The Effects of a Single Whole-Body Cryotherapy Exposure on Physiological, Performance, and Perceptual Responses of Professional Academy Soccer Players After Repeated Sprint Exercise.

    Science.gov (United States)

    Russell, Mark; Birch, Jack; Love, Thomas; Cook, Christian J; Bracken, Richard M; Taylor, Tom; Swift, Eamon; Cockburn, Emma; Finn, Charlie; Cunningham, Daniel; Wilson, Laura; Kilduff, Liam P

    2017-02-01

    Russell, M, Birch, J, Love, T, Cook, CJ, Bracken, RM, Taylor, T, Swift, E, Cockburn, E, Finn, C, Cunningham, D, Wilson, L, and Kilduff, LP. The effects of a single whole-body cryotherapy exposure on physiological, performance, and perceptual responses of professional academy soccer players after repeated sprint exercise. J Strength Cond Res 31(2): 415-421, 2017-In professional youth soccer players, the physiological, performance, and perceptual effects of a single whole-body cryotherapy (WBC) session performed shortly after repeated sprint exercise were investigated. In a randomized, counterbalanced, and crossover design, 14 habituated English Premier League academy soccer players performed 15 × 30 m sprints (each followed by a 10 m forced deceleration) on 2 occasions. Within 20 minutes of exercise cessation, players entered a WBC chamber (Cryo: 30 seconds at -60° C, 120 seconds at -135° C) or remained seated (Con) indoors in temperate conditions (∼25° C). Blood and saliva samples, peak power output (countermovement jump), and perceptual indices of recovery and soreness were assessed pre-exercise and immediately, 2-hour and 24-hour postexercise. When compared with Con, a greater testosterone response was observed at 2-hour (+32.5 ± 32.3 pg·ml, +21%) and 24-hour (+50.4 ± 48.9 pg·ml, +28%) postexercise (both P = 0.002) in Cryo (trial × treatment interaction: P = 0.001). No between-trial differences were observed for other salivary (cortisol and testosterone/cortisol ratio), blood (lactate and creatine kinase), performance (peak power output), or perceptual (recovery or soreness) markers (all trial × treatment interactions: P > 0.05); all of which were influenced by exercise (time effects: all P ≤ 0.05). A single session of WBC performed within 20 minutes of repeated sprint exercise elevated testosterone concentrations for 24 hours but did not affect any other performance, physiological, or perceptual measurements taken. Although unclear, WBC may be

  3. Detection of the effects of repeated dose combined propoxur and heavy metal exposure by measurement of certain toxicological, haematological and immune function parameters in rats.

    Science.gov (United States)

    Institóris, L; Siroki, O; Undeger, U; Basaran, N; Banerjee, B D; Dési, I

    2001-06-21

    In the present study, an immunotoxicity test system, containing general toxicological (body weight gain, organ weights), haematological (WBC,RBC, Ht, mean cell volume of the RBCs, cell content of the femoral bone marrow), and immune function (PFC assay, DTH reaction) investigations, was used for detection the effects of a 4 weeks repeated low dose combined oral exposure of male Wistar rats with propoxur and the heavy metals arsenic or mercury. Two doses of the compounds were used: a higher one (the lowest dose which resulted in significant change of at least one parameter examined in previous dose-effect experiments), and a lower one (the highest dose which proved to be non-effective). The applied doses were: 8.51 and 0.851 mg kg(-1) of propoxur, 13.3 and 3.33 mg kg(-1) of NaAsO(2), and 3.20 and 0.40 mg kg(-1) of HgCl(2). In the combination treatment, the high dose of propoxur was combined with the low dose of arsenic or mercury, and the high doses of each heavy metals were combined with the low dose of propoxur. The main finding of this study was that some of the combinations significantly altered the relative weight of liver, adrenals and kidneys, related to both the untreated and the high dose internal control. Among the immune functions examined, only the PFC content of the spleen showed a trend of changes in certain combinations versus the corresponding high dose control. According to the present results, combined exposure with propoxur and the heavy metals examined can modify the detection limit of the single compounds and/or may alter their toxic effects.

  4. Pediatric Brain: Repeated Exposure to Linear Gadolinium-based Contrast Material Is Associated with Increased Signal Intensity at Unenhanced T1-weighted MR Imaging.

    Science.gov (United States)

    Flood, Thomas F; Stence, Nicholas V; Maloney, John A; Mirsky, David M

    2017-01-01

    Purpose To determine whether repeated exposure of the pediatric brain to a linear gadolinium-based contrast agent (GBCA) is associated with an increase in signal intensity (SI) relative to that in GBCA-naive control subjects at unenhanced T1-weighted magnetic resonance (MR) imaging. Materials and Methods This single-center, retrospective study was approved by the institutional review board and compliant with HIPAA. The authors evaluated 46 pediatric patients who had undergone at least three GBCA-enhanced MR examinations (30 patients for two-group analysis and 16 for pre- and post-GBCA exposure comparisons) and 57 age-matched GBCA-naive control subjects. The SI in the globus pallidus, thalamus, dentate nucleus, and pons was measured at unenhanced T1-weighted MR imaging. Globus pallidus-thalamus and dentate nucleus-pons SI ratios were calculated and compared between groups and relative to total cumulative gadolinium dose, age, sex, and number of and mean time between GBCA-enhanced examinations. Analysis included the Wilcoxon signed rank test, Wilcoxon rank sum test, and Spearman correlation coefficient. Results Patients who underwent multiple GBCA-enhanced examinations had increased SI ratios within the dentate nucleus (mean SI ratio ± standard error of the mean for two-group comparison: 1.007 ± 0.0058 for GBCA-naive group and 1.046 ± 0.0060 for GBCA-exposed group [P mean SI ratio for pre- and post-GBCA comparison: 0.995 ± 0.0062 for pre-GBCA group and 1.035 ± 0.0063 for post-GBCA group [P mean SI ratio for two-group comparison: 1.131 ± 0.0070 for GBCA-naive group and 1.014 ± 0.0091 for GBCA-exposed group [P = .21]; mean SI ratio for pre- and post-GBCA comparison: 1.068 ± 0.0094 for pre-GBCA group and 1.093 ± 0.0134 for post-GBCA group [P = .12]). There was a significant correlation between dentate nucleus SI and total cumulative gadolinium dose (r = 0.4; 95% confidence interval [CI]: 0.03, 0.67; P = .03), but not between dentate nucleus SI and patient age

  5. Prospective study of leptospirosis transmission in an urban slum community: role of poor environment in repeated exposures to the Leptospira agent.

    Directory of Open Access Journals (Sweden)

    Ridalva D M Felzemburgh

    Full Text Available BACKGROUND: Leptospirosis has emerged as an urban health problem as slum settlements have rapidly spread worldwide and created conditions for rat-borne transmission. Prospective studies have not been performed to determine the disease burden, identify risk factors for infection and provide information needed to guide interventions in these marginalized communities. METHODOLOGY/PRINCIPAL FINDINGS: We enrolled and followed a cohort of 2,003 residents from a slum community in the city of Salvador, Brazil. Baseline and one-year serosurveys were performed to identify primary and secondary Leptospira infections, defined as respectively, seroconversion and four-fold rise in microscopic agglutination titers. We used multinomial logistic regression models to evaluate risk exposures for acquiring primary and secondary infection. A total of 51 Leptospira infections were identified among 1,585 (79% participants who completed the one-year follow-up protocol. The crude infection rate was 37.8 per 1,000 person-years. The secondary infection rate was 2.3 times higher than that of primary infection rate (71.7 and 31.1 infections per 1,000 person-years, respectively. Male gender (OR 2.88; 95% CI 1.40-5.91 and lower per capita household income (OR 0.54; 95% CI, 0.30-0.98 for an increase of $1 per person per day were independent risk factors for primary infection. In contrast, the 15-34 year age group (OR 10.82, 95% CI 1.38-85.08, and proximity of residence to an open sewer (OR 0.95; 0.91-0.99 for an increase of 1 m distance were significant risk factors for secondary infection. CONCLUSIONS/SIGNIFICANCE: This study found that slum residents had high risk (>3% per year for acquiring a Leptospira infection. Re-infection is a frequent event and occurs in regions of slum settlements that are in proximity to open sewers. Effective prevention of leptospirosis will therefore require interventions that address the infrastructure deficiencies that contribute to repeated

  6. Assessment of the Effects of Acute and Repeated Exposure to Blast Overpressure in Rodents: Towards a Greater Understanding of Blast and the Potential Ramifications for Injury in Humans Exposed to Blast

    Directory of Open Access Journals (Sweden)

    Stephen Thomas Ahlers

    2012-03-01

    Full Text Available Mild traumatic brain injury (mTBI resulting from exposure to improvised explosive devices (IEDs has fueled a requirement to develop animals models that mirror this condition using exposure to blast overpressure (BOP. En route to developing a model of repeated exposure to BOP we sought to initially characterize the effects of acute BOP exposure in rodents, focusing specifically on the levels of BOP exposure that produced clinical mTBI symptoms. We first measured BOP effects on gross motor function on a balance beam. Separate groups of unanesthetized rats were exposed (in different orientations to 40 kPa, 75 kPa and 120 kPa BOP exposure inside a pneumatically driven shock tube. Results demonstrated that rats exposed to 120 kPa demonstrated transient alterations or loss of consciousness indicated by a transient loss of righting and by increased latencies on the balance beam. The 120 kPa exposure was the threshold for overt pathology for acute BOP exposure with approximately 30% of rats presenting with evidence of subdural hemorrhage and cortical contusions. All animals exposed to 120 kPa BOP manifested evidence of significant pulmonary hemorrhage. Anterograde memory deficits were observed in rats exposed to 75 kPa facing the BOP wave and rats exposed to 120 kPa in the lateral (side orientation. We next assessed repeated exposure to either lateral or frontal 40 kPa BOP in anesthetized rats, once per day for 12 days. Results showed that repeated exposure in the frontal, but not side, orientation to the BOP wave produced a transitory learning deficit on a Morris water maze (MWM task as shown by significantly longer latencies to reach the submerged platform in the second and third blocks of a four block session. Implications of these data are discussed in relation to the manifestation of mTBI in military personnel exposed to IEDs. Finally, we suggest that there are multiple types of brain injury from blast.

  7. The preventive effect of vitamin C on the cellular and functional integrity of kidney cells in rats following repeated exposure to paraquat

    Directory of Open Access Journals (Sweden)

    Benjamin Nnamdi Okolonkwo

    2014-11-01

    Full Text Available Paraquat (PQ is a bipyridylium herbicide that is applied around trees in orchards and between crop rows to control broad-leaved and grassy weeds. Its oxidation results in the formation of superoxides which causes damage to cellular components. In this study, we determined the antioxidant effect vitamin C has on the cellular integrity of kidney function in rats following repeated exposure to PQ. Ninety-six male rats, grouped twelve rats per subgroup (A, Avit.c, B, Bvit.c, C, Cvit.c, D and Dvit.c were intraperitoneally injected with different sublethal increasing doses (0, 0, 2, 2, 4, 4, 6 and 6 mg/kg body weight of PQ respectively on biweekly (14 days intervals over a period of three months (84 days. Subsequently, the subgrouped animals (Avit.c, Bvit.c, Cvit.c and Dvit.c were maintained orally with 1 g/L vitamin C, while the other subgrouped animals (A, B, C and D received drinking water with negligible vitamin content throughout the study period. At the end of each monthly (28 days treatment, four animals per subgroup were selected. Urine samples were collected from each of the selected rats, after which each of the animals were anaesthetized with gaseous isoflurane and 5 mL of blood samples were collected using cardiac puncture procedure. The animals were later decapitated and their kidneys harvested. The samples collected were analyzed for urine [specific gravity (SG, pH, protein and glucose], blood (urea, creatinine, total protein and glucose, and the histological studies on kidney slides. The dose and exposure- time dependent PQ toxicity resulted in the reduction in urinary pH, elevation in urinary SG, and the detectable presence of protein and glucose in urine. It also caused marked elevation in serum urea and creatinine levels with reduction in serum protein and glucose levels and alterations in the cellular integrity of the renal architecture, especially the glomeruli and tubular tissues. Treatments on the PQ insulted animals with vitamin

  8. The Resting Motor Threshold - Restless or Resting?

    DEFF Research Database (Denmark)

    Karabanov, Anke Ninija; Raffin, Estelle Emeline; Siebner, Hartwig Roman

    2015-01-01

    Background The resting motor threshold (RMT) is used to individually adjust the intensity of transcranial magnetic stimulation (TMS) intensity and is assumed to be stable. Here we challenge this notion by showing that RMT expresses acute context-dependent fluctuations. Method In twelve participants...

  9. Prolonged Increase in the Sensitivity of the Posterior Ventral Tegmental Area to the Reinforcing Effects of Ethanol following Repeated Exposure to Cycles of Ethanol Access and Deprivation

    OpenAIRE

    Rodd, Zachary A.; Bell, Richard L.; McQueen, Victoria K.; Davids, Michelle R.; Hsu, Cathleen C.; Murphy, James M.; Li, Ting-Kai; Lumeng, Lawrence; McBride, William J.

    2005-01-01

    The posterior ventral tegmental area (VTA) is a neuroanatomical substrate mediating the reinforcing effects of ethanol in rats. Repeated alcohol deprivations produce robust ethanol intakes of alcohol-preferring (P) rats during relapse and increase the reinforcing effects of oral alcohol self-administration. The objective of this study was to test the hypothesis that alcohol drinking and repeated alcohol deprivations will increase the reinforcing effects of ethanol within the posterior VTA of ...

  10. RESTful Web Services Cookbook

    CERN Document Server

    Allamaraju, Subbu

    2010-01-01

    While the REST design philosophy has captured the imagination of web and enterprise developers alike, using this approach to develop real web services is no picnic. This cookbook includes more than 100 recipes to help you take advantage of REST, HTTP, and the infrastructure of the Web. You'll learn ways to design RESTful web services for client and server applications that meet performance, scalability, reliability, and security goals, no matter what programming language and development framework you use. Each recipe includes one or two problem statements, with easy-to-follow, step-by-step i

  11. Effects of prolonged bed rest on the total peripheral resistance baroreflex

    Science.gov (United States)

    Xiao, X.; Mukkamala, R.; Sheynberg, N.; Williams, G. H.; Cohen, R. J.; Mark, R. G. (Principal Investigator)

    2002-01-01

    Orthostatic intolerance following prolonged exposure to microgravity continues to be a primary concern of the human space program. Reduced autonomic tone has been demonstrated to contribute to this phenomenon, and the heart rate baroreflex, in particular, has been repeatedly shown to be impaired. However, only the works of Yelle et al. have attempted to address the role of the total peripheral resistance (TPR) baroreflex, a potentially more significant contributor to blood pressure regulation. We applied a previously developed method for estimating the static gains of both the arterial and cardiopulmonary TPR baroreflexes to data obtained before and after 16-day bed rest. Reductions in the estimated static gains of the arterial (statistically significant) and cardiopulmonary TPR baroreflexes were found after bed rest. This study supports the works of Yelle et al, which imply that the TPR baroreflex is reduced after spaceflight.

  12. FRS REST Services

    Science.gov (United States)

    FRS exposes several REST services that allows developers to utilize a live feed of data from the FRS database. This web page is intended for a technical audience and describes the content and purpose of each service available.

  13. Repeated intermittent alcohol exposure during the third trimester-equivalent increases expression of the GABA(A) receptor δ subunit in cerebellar granule neurons and delays motor development in rats.

    Science.gov (United States)

    Diaz, Marvin R; Vollmer, Cyndel C; Zamudio-Bulcock, Paula A; Vollmer, William; Blomquist, Samantha L; Morton, Russell A; Everett, Julie C; Zurek, Agnieszka A; Yu, Jieying; Orser, Beverley A; Valenzuela, C Fernando

    2014-04-01

    Exposure to ethanol (EtOH) during fetal development can lead to long-lasting alterations, including deficits in fine motor skills and motor learning. Studies suggest that these are, in part, a consequence of cerebellar damage. Cerebellar granule neurons (CGNs) are the gateway of information into the cerebellar cortex. Functionally, CGNs are heavily regulated by phasic and tonic GABAergic inhibition from Golgi cell interneurons; however, the effect of EtOH exposure on the development of GABAergic transmission in immature CGNs has not been investigated. To model EtOH exposure during the 3rd trimester-equivalent of human pregnancy, neonatal pups were exposed intermittently to high levels of vaporized EtOH from postnatal day (P) 2 to P12. This exposure gradually increased pup serum EtOH concentrations (SECs) to ∼60 mM (∼0.28 g/dl) during the 4 h of exposure. EtOH levels gradually decreased to baseline 8 h after the end of exposure. Surprisingly, basal tonic and phasic GABAergic currents in CGNs were not significantly affected by postnatal alcohol exposure (PAE). However, PAE increased δ subunit expression at P28 as detected by immunohistochemical and western blot analyses. Also, electrophysiological studies with an agonist that is highly selective for δ-containing GABA(A) receptors, 4,5,6,7-tetrahydroisoxazolo[4,5-c]pyridine-3-ol (THIP), showed an increase in THIP-induced tonic current. Behavioral studies of PAE rats did not reveal any deficits in motor coordination, except for a delay in the acquisition of the mid-air righting reflex that was apparent at P15 to P18. These findings demonstrate that repeated intermittent exposure to high levels of EtOH during the equivalent of the last trimester of human pregnancy has significant but relatively subtle effects on motor coordination and GABAergic transmission in CGNs in rats.

  14. Deployment Repeatability

    Science.gov (United States)

    2016-04-01

    controlled to great precision, but in a Cubesat , there may be no attitude determination at all. Such a Cubesat might treat sun angle and tumbling rates as...could be sensitive to small differences in motor controller timing. In these cases, the analyst might choose to model the entire deployment path, with...knowledge of the material damage model or motor controller timing precision. On the other hand, if many repeated and environmentally representative

  15. Effect of restrictions on television food advertising to children on exposure to advertisements for 'less healthy' foods: repeat cross-sectional study.

    Directory of Open Access Journals (Sweden)

    Jean Adams

    Full Text Available BACKGROUND: In 2007, new scheduling restrictions on television food advertising to children in the UK were announced. The aim of the restrictions was to "reduce significantly the exposure of children under 16 to high fat, salt or sugar (HFSS advertising". We explored the impact of the restrictions on relative exposure to HFSS food advertising among all viewers and among child television viewers, as well as adherence to the restrictions. METHODS: We conducted two cross-sectional studies of all advertisements broadcast in one region of the UK over one week periods--the first (week 1 six months before the restrictions were introduced, and the second (week 2 six months after. Data on what products were advertised were linked to data on how many people watched each advertisement. Nutritional content of foods advertised was added to the dataset and used to calculate HFSS status. Relative exposure was calculated as the proportion of all advertising person-minute-views (PMVs that were for HFSS foods. RESULTS: 1,672,417 advertising PMV were included. 14.6% of advertising PMV were for food and 51.1% of these were for HFSS food. Relative exposure of all viewers to HFSS food advertising increased between study weeks 1 and 2 (odds ratio (99% confidence intervals = 1·54 (1·51 to 1·57. Exposure of children to HFSS food advertising did not change between study weeks 1 and 2 (odds ratio (99% confidence intervals = 1·05 (0·99 to 1·12. There was almost universal adherence to the restrictions. CONCLUSIONS: Despite good adherence to the restrictions, they did not change relative exposure of children to HFSS advertising and were associated with an increase in relative exposure of all viewers to HFSS advertising. Stronger restrictions targeting a wider range of advertisements are necessary to reduce exposure of children to marketing of less healthful foods.

  16. Effect of restrictions on television food advertising to children on exposure to advertisements for 'less healthy' foods: repeat cross-sectional study.

    Science.gov (United States)

    Adams, Jean; Tyrrell, Rachel; Adamson, Ashley J; White, Martin

    2012-01-01

    In 2007, new scheduling restrictions on television food advertising to children in the UK were announced. The aim of the restrictions was to "reduce significantly the exposure of children under 16 to high fat, salt or sugar (HFSS) advertising". We explored the impact of the restrictions on relative exposure to HFSS food advertising among all viewers and among child television viewers, as well as adherence to the restrictions. We conducted two cross-sectional studies of all advertisements broadcast in one region of the UK over one week periods--the first (week 1) six months before the restrictions were introduced, and the second (week 2) six months after. Data on what products were advertised were linked to data on how many people watched each advertisement. Nutritional content of foods advertised was added to the dataset and used to calculate HFSS status. Relative exposure was calculated as the proportion of all advertising person-minute-views (PMVs) that were for HFSS foods. 1,672,417 advertising PMV were included. 14.6% of advertising PMV were for food and 51.1% of these were for HFSS food. Relative exposure of all viewers to HFSS food advertising increased between study weeks 1 and 2 (odds ratio (99% confidence intervals) = 1·54 (1·51 to 1·57)). Exposure of children to HFSS food advertising did not change between study weeks 1 and 2 (odds ratio (99% confidence intervals) = 1·05 (0·99 to 1·12)). There was almost universal adherence to the restrictions. Despite good adherence to the restrictions, they did not change relative exposure of children to HFSS advertising and were associated with an increase in relative exposure of all viewers to HFSS advertising. Stronger restrictions targeting a wider range of advertisements are necessary to reduce exposure of children to marketing of less healthful foods.

  17. Repeated whole cigarette smoke exposure alters cell differentiation and augments secretion of inflammatory mediators in air-liquid interface three-dimensional co-culture model of human bronchial tissue.

    Science.gov (United States)

    Ishikawa, Shinkichi; Ito, Shigeaki

    2017-02-01

    In vitro models of human bronchial epithelium are useful for toxicological testing because of their resemblance to in vivo tissue. We constructed a model of human bronchial tissue which has a fibroblast layer embedded in a collagen matrix directly below a fully-differentiated epithelial cell layer. The model was applied to whole cigarette smoke (CS) exposure repeatedly from an air-liquid interface culture while bronchial epithelial cells were differentiating. The effects of CS exposure on differentiation were determined by histological and gene expression analyses on culture day 21. We found a decrease in ciliated cells and perturbation of goblet cell differentiation. We also analyzed the effects of CS exposure on the inflammatory response, and observed a significant increase in secretion of IL-8, GRO-α, IL-1β, and GM-CSF. Interestingly, secretion of these mediators was augmented with repetition of whole CS exposure. Our data demonstrate the usefulness of our bronchial tissue model for in vitro testing and the importance of exposure repetition in perturbing the differentiation and inflammation processes.

  18. 生命早期饥荒暴露对成年后静息心率增快的影响%The effects of exposure to the famine during early life with elevated resting heart rate in the adult

    Institute of Scientific and Technical Information of China (English)

    李玉卿; 朱丽媛; 王洁蕊; 陈朔华; 温炜; 韩红锋; 季春鹏; 崔刘福; 吴寿岭

    2015-01-01

    Objective To investigate the association between exposure to the famine during early life and elevated resting heart rate(RHR)in adulthood. Method From June 2006 to October 2007, the employees of kailuan group who took part in the health examination were selected. Of those, 18 619 cases who was born during October 1 ,1956 to September 30,1964 in Hebei province were finally included in the analysis based on the inclusion and exclusion criteria. All the subjects were received questionnaire survey, smoking and drinking, physical examination, Lab examination and the measurement of RHR. The subjects of famine exposure group(3 190 cases) were born from October 1 ,1959 to September 30, 1961,semi⁃exposure group( 3 851 cases) were born from October 1,1958 to September 30, 1959 and from October 1, 1961 to September 30, 1962 ,control group(11 578 cases) were born from October 1, 1956 to September 30, 1958 and from October 1, 1962 to September 30, 1964. The RHR and the detection rate of elevated RHR were compared among the three groups. The Multivariate logistic regression model was used to analyze the association between of exposure to famine during early life and elevated RHR in adulthood. Results The RHR level was higher in famine exposure group and semi⁃exposed group than control group, which were (74.34 ± 9.71),(74.41 ± 9.48)and(73.90 ± 9.45)beat per minute(bpm)(P values were 0.003 and 0.020, respectively).In all of the subjects. The results of multivariate logistic regression showed that exposure of famine during early life increased the risk of elevated RHR in adulthood after adjustment for age,gender and other confounders (OR=1.10, 95%CI:1.01-1.21). In men, exposure of famine during early life also increased the risk of elevated RHR in adulthood(OR=1.15, 95%CI:1.04-1.28);In women, there was no association between the famine exposure and elevated RHR (OR=0.92,95%CI:0.74-1.14). Conclusion Exposure of famine during early life increases the risk of elevated RHR in

  19. Expression of nuclear factor-kappa B in hepatic tissue and its significance in rats after repeated and sustained +10Gz exposure

    Directory of Open Access Journals (Sweden)

    Lei LIU

    2015-07-01

    Full Text Available Objective To observe the injury to liver cells, and to investigate the changes in nuclear factor-kappa B (NF-κB in the liver tissue after exposure to positive ten acceleration (+10Gz. Methods Twenty-four adult male Wistar rats were randomly assigned to four groups: blank control, exposure groups A, B, and C. The rats of three exposure groups were subjected to centrifugal force of +10Gz for 0.5, 24, and 48h respectively, which was carried out in an Air Force Institute of Aviation Medicine. Plasma aspartate aminotransferase (AST and alanine aminotransferase (ALT were determined. Liver tissue was harvested for immunohistochemistry, and Western blotting was performed for expression of NF-κB. Results After +10 Gz exposure, rats of the group A showed shaggy hair, apathetic to food, and laid still, while group B rats showed shaggy hair, took a little food with lowering of activity level. The rats in group C showed normal activities. Both the levels of serum AST and ALT were elevated, and they were higher in group B than that of groups A and C (P0.05. Western blotting and immunohistochemical staining showed that the NF-κB expression levels were significantly higher in exposure groups than in control group (P0.05. Immunohistochemical examination revealed NF-κBpositive products were localized predominantly in the hepatocytes, and also in the inflammatory cells and Kupffer cells. These products could be divided into three types: cytosolic type, karyotype, and nuclear-cytoplasm type, and they existed alone or in combination. Conclusion Exposure to +10Gz, especially in the early stage, acts as a stress to induce the activation of NF-κB, suggesting that NF-κB plays an important role in the cascade reactions and adaptation to the acceleration stress. DOI: 10.11855/j.issn.0577-7402.2015.07.17

  20. Effect of repeated forearm muscle cooling on the adaptation of skeletal muscle metabolism in humans

    Science.gov (United States)

    Wakabayashi, Hitoshi; Nishimura, Takayuki; Wijayanto, Titis; Watanuki, Shigeki; Tochihara, Yutaka

    2017-01-01

    This study aimed to investigate the effect of repeated cooling of forearm muscle on adaptation in skeletal muscle metabolism. It is hypothesized that repeated decreases of muscle temperature would increase the oxygen consumption in hypothermic skeletal muscle. Sixteen healthy males participated in this study. Their right forearm muscles were locally cooled to 25 °C by cooling pads attached to the skin. This local cooling was repeated eight times on separate days for eight participants (experimental group), whereas eight controls received no cold exposure. To evaluate adaptation in skeletal muscle metabolism, a local cooling test was conducted before and after the repeated cooling period. Change in oxy-hemoglobin content in the flexor digitorum at rest and during a 25-s isometric handgrip (10% maximal voluntary construction) was measured using near-infrared spectroscopy at every 2 °C reduction in forearm muscle temperature. The arterial blood flow was occluded for 15 s by upper arm cuff inflation at rest and during the isometric handgrip. The oxygen consumption in the flexor digitorum muscle was evaluated by a slope of the oxy-hemoglobin change during the arterial occlusion. In the experimental group, resting oxygen consumption in skeletal muscle did not show any difference between pre- and post-intervention, whereas muscle oxygen consumption during the isometric handgrip was significantly higher in post-intervention than in pre-test from thermoneutral baseline to 31 °C muscle temperature (P < 0.05). This result indicated that repeated local muscle cooling might facilitate oxidative metabolism in the skeletal muscle. In summary, skeletal muscle metabolism during submaximal isometric handgrip was facilitated after repeated local muscle cooling.

  1. Repeated exposure to corticosterone increases depression-like behavior in two different versions of the forced swim test without altering nonspecific locomotor activity or muscle strength.

    Science.gov (United States)

    Marks, Wendie; Fournier, Neil M; Kalynchuk, Lisa E

    2009-08-01

    We have recently shown that repeated high dose injections of corticosterone (CORT) reliably increase depression-like behavior on a modified one-day version of the forced swim test. The main purpose of this experiment was to compare the effect of these CORT injections on our one-day version of the forced swim test and the more traditional two-day version of the test. A second purpose was to determine whether altered behavior in the forced swim test could be due to nonspecific changes in locomotor activity or muscle strength. Separate groups of rats received a high dose CORT injection (40 mg/kg) or a vehicle injection once per day for 21 consecutive days. Then, half the rats from each group were exposed to the traditional two-day forced swim test and the other half were exposed to our one-day forced swim test. After the forced swim testing, all the rats were tested in an open field and in a wire suspension grip strength test. The CORT injections significantly increased the time spent immobile and decreased the time spent swimming in both versions of the forced swim test. However, they had no significant effect on activity in the open field or grip strength in the wire suspension test. These results show that repeated CORT injections increase depression-like behavior regardless of the specific parameters of forced swim testing, and that these effects are independent of changes in locomotor activity or muscle strength.

  2. REST based service composition

    DEFF Research Database (Denmark)

    Grönvall, Erik; Ingstrup, Mads; Pløger, Morten

    2011-01-01

    This paper presents an ongoing work developing and testing a Service Composition framework based upon the REST architecture named SECREST. A minimalistic approach have been favored instead of a creating a complete infrastructure. One focus has been on the system's interaction model. Indeed, an aim...

  3. Surviving Bed Rest

    Science.gov (United States)

    ... your pregnancy — and your bed rest start a family tree that you can share with your child someday firm up your baby-name choices; use books and websites for ideas organize photo albums read anything — ... people (friends and family) whom you know will probably give gifts build ...

  4. Curcumin exposure induces expression of the Parkinson's disease-associated leucine-rich repeat kinase 2 (LRRK2) in rat mesencephalic cells.

    Science.gov (United States)

    Ortiz-Ortiz, Miguel A; Morán, José M; Ruiz-Mesa, Luz M; Niso-Santano, Mireia; Bravo-SanPedro, José M; Gómez-Sánchez, Rubén; González-Polo, Rosa A; Fuentes, José M

    2010-01-04

    Turmeric (curry powder), an essential ingredient of culinary preparations of Southeast Asia, contains a major polyphenolic compound known as curcumin or diferuloylmethane. Curcumin is a widely studied phytochemical with a variety of biological activities. In addition to its anti-inflammatory and antimicrobial/antiviral properties, curcumin is considered as a cancer chemopreventive agent as well as a modulator of gene expression and a potent antioxidant. Since oxidative stress has been implicated in the degeneration of dopaminergic neurons in the substantia nigra in Parkinson's disease (PD), curcumin has been proposed to have potential therapeutic value for the treatment of neurodegenerative diseases such as PD. Following age, a family history of PD is the most commonly reported risk factor, suggesting a genetic component of the disease in a subgroup of patients. The LRRK2 gene has emerged as the gene most commonly associated with both familial and sporadic PD. Here, we report that exposure of rat mesencephalic cells to curcumin induces the expression of LRRK2 mRNA and protein in a time-dependent manner. The expression of other PD-related genes, such alpha-synuclein and parkin, was not affected by exposure to curcumin, and PTEN-induced putative kinase 1 (PINK1) was not expressed in rat mesencephalic cells. As LRRK2 overexpression is strongly associated with the pathological inclusions found in several neurodegenerative disorders, further studies are needed to evaluate the effects of curcumin as a therapeutic agent for neurodegenerative diseases.

  5. Subclinical effects of groundwater contaminants. Pt. 4. Effects of repeated oral exposure to combinations of benzene and toluene on regional brain monoamine metabolism in mice

    Energy Technology Data Exchange (ETDEWEB)

    Hsieh, G.C.; Parker, R.D.R. (Utah State Univ., Logan, UT (USA). Dept. of Biology); Sharma, R.P. (Utah State Univ., Logan, UT (USA). Dept. of Animal, Dairy and Veterinary Sciences)

    1990-11-01

    The effect of combined treatment with benzene and toluene on the endogenous concentrations of the catecholamines norepinephrine (NE) and dopamine (DA), the catecholamine metabolites vanillylmandelic acid (VMA), 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), and the indoleamine serotonin (5-HT) and its metabolite 5-hydroxyindoleacetic acid (5-HIAA), were investigated in six discrete brain regions of CD-1 mice. Groups of male, adult mice were continuously exposed to benzene (166 mg/l), toluene (80 and 325 mg/l), and combinations of benzene + toluene (80 or 325 mg/l) in drinking water for 4 weeks. Benzene produced increases of NE in the hypothalamus, cortex, midbrain and medulla oblongata, DA in the hypothalamus and corpus striatum, and 5-HT in all dissected brain regions except cerebellum. Elevated levels of various monoamine metabolites were also observed in these brain areas. Toluene ingestion alone also significantly increased the concentrations of NE, DA, 5-HT, and their metabolites in several brain regions. Mice given the combined treatments exhibited raised regional neurochemical levels when compared to the untreated controls. Increased concentrations of biogenic amine metabolites in several brain regions were greater in the combined exposures of benzene and toluene than when either chemical was used alone. The findings were different from those observed on immune parameters using similar treatment protocols, where simultaneous exposure to toluene prevented the immunotoxic effects of benzene. (orig./MG).

  6. Effect of repeated forearm muscle cooling on the adaptation of skeletal muscle metabolism in humans

    Science.gov (United States)

    Wakabayashi, Hitoshi; Nishimura, Takayuki; Wijayanto, Titis; Watanuki, Shigeki; Tochihara, Yutaka

    2017-07-01

    This study aimed to investigate the effect of repeated cooling of forearm muscle on adaptation in skeletal muscle metabolism. It is hypothesized that repeated decreases of muscle temperature would increase the oxygen consumption in hypothermic skeletal muscle. Sixteen healthy males participated in this study. Their right forearm muscles were locally cooled to 25 °C by cooling pads attached to the skin. This local cooling was repeated eight times on separate days for eight participants (experimental group), whereas eight controls received no cold exposure. To evaluate adaptation in skeletal muscle metabolism, a local cooling test was conducted before and after the repeated cooling period. Change in oxy-hemoglobin content in the flexor digitorum at rest and during a 25-s isometric handgrip (10% maximal voluntary construction) was measured using near-infrared spectroscopy at every 2 °C reduction in forearm muscle temperature. The arterial blood flow was occluded for 15 s by upper arm cuff inflation at rest and during the isometric handgrip. The oxygen consumption in the flexor digitorum muscle was evaluated by a slope of the oxy-hemoglobin change during the arterial occlusion. In the experimental group, resting oxygen consumption in skeletal muscle did not show any difference between pre- and post-intervention, whereas muscle oxygen consumption during the isometric handgrip was significantly higher in post-intervention than in pre-test from thermoneutral baseline to 31 °C muscle temperature ( P muscle cooling might facilitate oxidative metabolism in the skeletal muscle. In summary, skeletal muscle metabolism during submaximal isometric handgrip was facilitated after repeated local muscle cooling.

  7. Aryl hydrocarbon receptor knockout rats are insensitive to the pathological effects of repeated oral exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin.

    Science.gov (United States)

    Harrill, Joshua A; Layko, Debra; Nyska, Abraham; Hukkanen, Renee R; Manno, Rosa Anna; Grassetti, Andrea; Lawson, Marie; Martin, Greg; Budinsky, Robert A; Rowlands, J Craig; Thomas, Russell S

    2016-06-01

    Sustained activation of the aryl hydrocarbon receptor (AHR) is believed to be the initial key event in AHR receptor-mediated tumorigenesis in the rat liver. The role of AHR in mediating pathological changes in the liver prior to tumor formation was investigated in a 4-week, repeated-dose study using adult female wild-type (WT) and AHR knockout (AHR-KO) rats treated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Beginning at 8 weeks of age, AHR-KO and WT rats were dosed by oral gavage with varying concentrations of TCDD (0, 3, 22, 100, 300 and 1000 ng kg(-1)  day(-1) ). Lung, liver and thymus histopathology, hematology, serum chemistry and the distribution of TCDD in liver and adipose tissue were examined. Treatment-related increases in the severity of liver and thymus pathology were observed in WT, but not AHR-KO rats. In the liver, these included hepatocellular hypertrophy, bile duct hyperplasia, multinucleated hepatocytes and inflammatory cell foci. A loss of cellularity in the thymic cortex and thymic atrophy was observed. Treatment-related changes in serum chemistry parameters were also observed in WT, but not AHR-KO rats. Finally, dose-dependent accumulation of TCDD was observed primarily in the liver of WT rats and primarily in the adipose tissue of AHR-KO rats. The results suggest that AHR activation is the initial key event underlying the progression of histological effects leading to liver tumorigenesis following TCDD treatment. Copyright © 2015 John Wiley & Sons, Ltd.

  8. Prolonged rest period enables the detection of micronucleated hepatocytes in the liver of young adult rats after a single dose of diethylnitrosamine or mitomycin C.

    Science.gov (United States)

    Shimada, Keisuke; Yamamoto, Mika; Takashima, Miyuki; Seki, Jiro; Miyamae, Yoichi; Wakata, Akihiro

    2015-09-01

    A repeated-dose micronucleus assay utilizing young adult rat hepatocytes was recently developed to evaluate the genotoxicity. In this assay, accumulation of micronucleated hepatocytes (MNHEPs) induced by repeated dosing of genotoxic chemicals is considered to be a key factor in the detection of micronuclei induction. Then, we hypothesized that the period following chemical exposure enable the detection of MNHEP induction in young adult rats, namely that MNHEPs can be generated from chromosomally damaged cells and accumulate following initiation of chemical exposure until sampling. We therefore measured MNHEP induction at 2 or 4 weeks after a single oral administration of 12.5, 50, or 100mg/kg of diethylnitrosamine (DEN) or an intraperitoneal administration of 0.5, 1.0, or 2.0mg/kg of mitomycin C (MMC) to young adult rats. Results showed a statistically significant, dose-dependent increase in the numbers of MNHEPs in DEN- or MMC-treated rats, indicating that prolonged rest period following a single dose of a genotoxic chemical enables the detection of MNHEP induction in the liver of young adult rats. From these results, a single oral administration of 50mg/kg of DEN with a 2- or 4- week rest period can be used as a positive control in repeated-dose liver micronucleus assays. This procedure is superior in terms of labor saving and animal welfare to repeated dosing of DEN.

  9. Repeated exposure of human fibroblasts to ionizing radiation reveals an adaptive response that is not mediated by interleukin-6 or TGF-{beta}

    Energy Technology Data Exchange (ETDEWEB)

    Dieriks, Birger, E-mail: birger.dieriks@ugent.be [Bio-imaging and Cytometry Unit, Department of Molecular Biotechnology, Ghent University, Coupure Links 653, 9000 Gent (Belgium); De Vos, Winnok [Bio-imaging and Cytometry Unit, Department of Molecular Biotechnology, Ghent University, Coupure Links 653, 9000 Gent (Belgium); Baatout, Sarah [Bio-imaging and Cytometry Unit, Department of Molecular Biotechnology, Ghent University, Coupure Links 653, 9000 Gent (Belgium); Radiobiology Unit, Laboratory Molecular and Cellular Biology, Radiobiology Unit, Belgian Nuclear Research Center, SCK.CEN, Boeretang 200, 2400 Mol (Belgium); Van Oostveldt, Patrick, E-mail: Patrick.VanOostveldt@UGent.be [Bio-imaging and Cytometry Unit, Department of Molecular Biotechnology, Ghent University, Coupure Links 653, 9000 Gent (Belgium)

    2011-10-01

    Exposing cells to a low dose can protect them against a subsequent higher exposure. This phenomenon is known as adaptive response and is frequently observed in a variety of cells. Even though similarities are suspected with other non-targeted effects, such as bystander effects, the exact mechanism behind adaptive response is not fully clarified. In this study human primary fibroblasts were tested for their response to ionizing radiation (IR) after administrating a low priming dose (0.1-0.5 Gy). Both the abundance of {gamma}H2AX as a marker for double-stranded breaks and the levels of cytokines, secreted in the medium, were monitored in time. Upon challenge, IR-primed cells showed modified {gamma}H2AX spot size distributions and altered repair kinetics, consistent with an adaptive response. In addition, 24 h after priming with IR, four cytokines were significantly upregulated in the medium - GM-CSF (1.33x); IL6 (4.24x); IL8 (1.33x); TGF-{beta} (1.46x). In order to mimick the protective effect of IR priming, we primed the cells with either IL6 or TGF-{beta}. This did not elicit an altered {gamma}H2AX response as observed in IR-primed cells, indicating that the adaptive response in these primary fibroblasts is regulated in an IL-6 and TGF-{beta} independent manner.

  10. School-based intervention with children. Peer-modeling, reward and repeated exposure reduce food neophobia and increase liking of fruits and vegetables.

    Science.gov (United States)

    Laureati, Monica; Bergamaschi, Valentina; Pagliarini, Ella

    2014-12-01

    This study investigated the effectiveness of the 'Food Dudes' school-based intervention consisting of rewards, peer-modeling and food exposure on food neophobia and the liking of fruits and vegetables (FV) in a large cohort of children. Five-hundred sixty children recruited from three schools were assigned to the experimental or control group. For 16 days, children in the experimental group watched motivational videos, were read letters to encourage them to eat FV and received a small reward for eating one portion of both a fruit and a vegetable. The control group was only provided with FV for the same time period. Food neophobia and liking were measured in both groups of children before and after the intervention, and a follow-up measurement was carried out 6 months later. The intervention was effective in reducing food neophobia and, most importantly, a persistent effect was observed 6 months after the intervention as children of the experimental group showed significantly lower neophobia scores than the control group. Additionally, the program was effective in increasing liking for both FV; however, this effect was maintained only for fruit after 6 months.

  11. Rest mass or inertial mass?

    OpenAIRE

    Khrapko, R. I.

    2001-01-01

    Rest mass takes the place of inertial mass in modern physics textbooks. It seems to be wrong. But this phenomenon is hidden away by the facts that rest mass adherents busily call rest mass "mass", not rest mass, and the word "mass" is associated with a measure of inertia. This topic has been considered by the author in the article "What is mass?" [1, 2, 3]. Additional arguments to a confirmation of such a thesis are presented here.

  12. In vitro systems toxicology approach to investigate the effects of repeated cigarette smoke exposure on human buccal and gingival organotypic epithelial tissue cultures

    Science.gov (United States)

    Schlage, Walter K.; Kostadinova, Radina; Xiang, Yang; Sewer, Alain; Majeed, Shoaib; Kuehn, Diana; Frentzel, Stefan; Talikka, Marja; Geertz, Marcel; Mathis, Carole; Ivanov, Nikolai; Hoeng, Julia; Peitsch, Manuel C.

    2014-01-01

    Smoking has been associated with diseases of the lung, pulmonary airways and oral cavity. Cytologic, genomic and transcriptomic changes in oral mucosa correlate with oral pre-neoplasia, cancer and inflammation (e.g. periodontitis). Alteration of smoking-related gene expression changes in oral epithelial cells is similar to that in bronchial and nasal epithelial cells. Using a systems toxicology approach, we have previously assessed the impact of cigarette smoke (CS) seen as perturbations of biological processes in human nasal and bronchial organotypic epithelial culture models. Here, we report our further assessment using in vitro human oral organotypic epithelium models. We exposed the buccal and gingival organotypic epithelial tissue cultures to CS at the air–liquid interface. CS exposure was associated with increased secretion of inflammatory mediators, induction of cytochrome P450s activity and overall weak toxicity in both tissues. Using microarray technology, gene-set analysis and a novel computational modeling approach leveraging causal biological network models, we identified CS impact on xenobiotic metabolism-related pathways accompanied by a more subtle alteration in inflammatory processes. Gene-set analysis further indicated that the CS-induced pathways in the in vitro buccal tissue models resembled those in the in vivo buccal biopsies of smokers from a published dataset. These findings support the translatability of systems responses from in vitro to in vivo and demonstrate the applicability of oral organotypical tissue models for an impact assessment of CS on various tissues exposed during smoking, as well as for impact assessment of reduced-risk products. PMID:25046638

  13. Reductions in blood lead overestimate reductions in brain lead following repeated succimer regimens in a rodent model of childhood lead exposure.

    Science.gov (United States)

    Stangle, Diane E; Strawderman, Myla S; Smith, Donald; Kuypers, Mareike; Strupp, Barbara J

    2004-03-01

    Although many studies have demonstrated the efficacy of succimer chelation in reducing blood and brain lead levels, the relative efficacy of the drug in the two tissues is less well understood. This issue is important because blood lead levels after chelation are used clinically to estimate reductions in the brain, the most critical organ in considering lead-induced neurotoxicity. The present study was designed to further investigate this issue, using multiple chelation regimens. Long-Evans rats were exposed to one of three lead exposure regimens from birth until postnatal day 40, followed by treatment with succimer (one or two 3-week regimens) or vehicle. The results indicated that one succimer regimen was significantly superior to vehicle treatment in lowering lead levels in both blood and brain across the entire 8-week follow-up period. Similarly, a second succimer regimen offered significant additional benefit relative to one regimen for both blood and brain across the 4-week follow-up period. However, several findings revealed that succimer-induced reductions in brain lead lagged behind reductions in blood lead and were generally smaller in magnitude. Furthermore, a rebound was detected in blood, but not brain, lead levels after both succimer regimens. Given the results of this study, we urge caution in using blood lead as a surrogate for brain lead levels, particularly during and immediately after chelation treatment when reductions in blood lead levels overestimate reductions in brain lead levels. The present results suggest that, in clinical use, succimer treatment may need to extend beyond the point at which blood lead levels have dropped to an "acceptable" target value in order to effectively reduce brain lead levels and minimize neurotoxicity.

  14. In vitro systems toxicology approach to investigate the effects of repeated cigarette smoke exposure on human buccal and gingival organotypic epithelial tissue cultures.

    Science.gov (United States)

    Schlage, Walter K; Iskandar, Anita R; Kostadinova, Radina; Xiang, Yang; Sewer, Alain; Majeed, Shoaib; Kuehn, Diana; Frentzel, Stefan; Talikka, Marja; Geertz, Marcel; Mathis, Carole; Ivanov, Nikolai; Hoeng, Julia; Peitsch, Manuel C

    2014-10-01

    Smoking has been associated with diseases of the lung, pulmonary airways and oral cavity. Cytologic, genomic and transcriptomic changes in oral mucosa correlate with oral pre-neoplasia, cancer and inflammation (e.g. periodontitis). Alteration of smoking-related gene expression changes in oral epithelial cells is similar to that in bronchial and nasal epithelial cells. Using a systems toxicology approach, we have previously assessed the impact of cigarette smoke (CS) seen as perturbations of biological processes in human nasal and bronchial organotypic epithelial culture models. Here, we report our further assessment using in vitro human oral organotypic epithelium models. We exposed the buccal and gingival organotypic epithelial tissue cultures to CS at the air-liquid interface. CS exposure was associated with increased secretion of inflammatory mediators, induction of cytochrome P450s activity and overall weak toxicity in both tissues. Using microarray technology, gene-set analysis and a novel computational modeling approach leveraging causal biological network models, we identified CS impact on xenobiotic metabolism-related pathways accompanied by a more subtle alteration in inflammatory processes. Gene-set analysis further indicated that the CS-induced pathways in the in vitro buccal tissue models resembled those in the in vivo buccal biopsies of smokers from a published dataset. These findings support the translatability of systems responses from in vitro to in vivo and demonstrate the applicability of oral organotypical tissue models for an impact assessment of CS on various tissues exposed during smoking, as well as for impact assessment of reduced-risk products.

  15. Cold habituation does not improve manual dexterity during rest and exercise in 5 °C

    Science.gov (United States)

    Muller, Matthew D.; Seo, Yongsuk; Kim, Chul-Ho; Ryan, Edward J.; Pollock, Brandon S.; Burns, Keith J.; Glickman, Ellen L.

    2014-04-01

    When exposed to a cold environment, a barehanded person experiences pain, cold sensation, and reduced manual dexterity. Both acute (e.g. exercise) and chronic (e.g. cold acclimatization or habituation) processes might lessen these negative effects. The purpose of this experiment was to determine the effect of cold habituation on physiology, perception, and manual dexterity during rest, exercise, and recovery in 5 °C. Six cold weather athletes (CWA) and eight non habituated men (NON) volunteered to participate in a repeated measures cross-over design. The protocol was conducted in 5 °C and was 90 min of resting cold exposure, 30 min of cycle ergometry exercise (50 % VO2 peak), and 60 min of seated recovery. Core and finger skin temperature, metabolic rate, Purdue Pegboard dexterity performance, hand pain, thermal sensation, and mood were quantified. Exercise-induced finger rewarming (EIFRW) was calculated for each hand. During 90 min of resting exposure to 5 °C, the CWA had a smaller reduction in finger temperature, a lower metabolic rate, less hand pain, and less negative mood. Despite this cold habituation, dexterity performance was not different between groups. In response to cycle ergometry, EIFRW was greater in CWA (~12 versus 7 °C) and occurred at lower core temperatures (37.02 versus 37.31 °C) relative to NON but dexterity was not greater during post-exercise recovery. The current data indicate that cold habituated men (i.e., CWA) do not perform better on the Purdue Pegboard during acute cold exposure. Furthermore, despite augmented EIFRW in CWA, dexterity during post-exercise recovery was similar between groups.

  16. Removable partial dentures without rests.

    Science.gov (United States)

    Meinig, D A

    1994-04-01

    Ever since Bonwill recommended the use of rests on removable partial dentures in 1899, rests have been universally considered inviolate and have gone unchallenged and untested. The author claims that removable partial dentures without rests may not cause the adverse conditions usually predicted, such as gingival stripping, gingival inflammation, mutilated residual ridges, or extensive and rapid resorption of the alveolar ridges. In removable partial dentures made by the author for several patients, the residual ridge remained stable and in physiologic equilibrium when rests were not used. A history of the long-term effect on patients wearing partial dentures with and without rests is presented.

  17. Resting cerebral blood flow

    Science.gov (United States)

    Ances, B M.; Sisti, D; Vaida, F; Liang, C L.; Leontiev, O; Perthen, J E.; Buxton, R B.; Benson, D; Smith, D M.; Little, S J.; Richman, D D.; Moore, D J.; Ellis, R J.

    2009-01-01

    Objective: HIV enters the brain soon after infection causing neuronal damage and microglial/astrocyte dysfunction leading to neuropsychological impairment. We examined the impact of HIV on resting cerebral blood flow (rCBF) within the lenticular nuclei (LN) and visual cortex (VC). Methods: This cross-sectional study used arterial spin labeling MRI (ASL-MRI) to measure rCBF within 33 HIV+ and 26 HIV− subjects. Nonparametric Wilcoxon rank sum test assessed rCBF differences due to HIV serostatus. Classification and regression tree (CART) analysis determined optimal rCBF cutoffs for differentiating HIV serostatus. The effects of neuropsychological impairment and infection duration on rCBF were evaluated. Results: rCBF within the LN and VC were significantly reduced for HIV+ compared to HIV− subjects. A 2-tiered CART approach using either LN rCBF ≤50.09 mL/100 mL/min or LN rCBF >50.09 mL/100 mL/min but VC rCBF ≤37.05 mL/100 mL/min yielded an 88% (29/33) sensitivity and an 88% (23/26) specificity for differentiating by HIV serostatus. HIV+ subjects, including neuropsychologically unimpaired, had reduced rCBF within the LN (p = 0.02) and VC (p = 0.001) compared to HIV− controls. A temporal progression of brain involvement occurred with LN rCBF significantly reduced for both acute/early (<1 year of seroconversion) and chronic HIV-infected subjects, whereas rCBF in the VC was diminished for only chronic HIV-infected subjects. Conclusion: Resting cerebral blood flow (rCBF) using arterial spin labeling MRI has the potential to be a noninvasive neuroimaging biomarker for assessing HIV in the brain. rCBF reductions that occur soon after seroconversion possibly reflect neuronal or vascular injury among HIV+ individuals not yet expressing neuropsychological impairment. GLOSSARY AEH = acute/early HIV infection; ANOVA = analysis of variance; ASL-MRI = arterial spin labeling MRI; CART = classification and regression tree; CBF = cerebral blood flow; CH = chronic HIV

  18. The Effects of Long Duration Bed Rest on Functional Mobility and Balance: Relationship to Resting State Motor Cortex Connectivity

    Science.gov (United States)

    Erdeniz, B.; Koppelmans, V.; Bloomberg, J. J.; Kofman, I. S.; DeDios, Y. E.; Riascos-Castaneda, R. F.; Wood, S. J.; Mulavara, A. P.; Seidler, R. D.

    2014-01-01

    NASA offers researchers from a variety of backgrounds the opportunity to study bed rest as an experimental analog for space flight. Extended exposure to a head-down tilt position during long duration bed rest can resemble many of the effects of a low-gravity environment such as reduced sensory inputs, body unloading and increased cephalic fluid distribution. The aim of our study is to a) identify changes in brain function that occur with prolonged bed rest and characterize their recovery time course; b) assess whether and how these changes impact behavioral and neurocognitive performance. Thus far, we completed data collection from six participants that include task based and resting state fMRI. The data have been acquired through the bed rest facility located at the University of Texas Medical Branch (Galveston, TX). Subjects remained in bed with their heads tilted down 6 degrees below their feet for 70 consecutive days. Behavioral measures and neuroimaging assessments were obtained at seven time points: a) 7 and 12 days before bed rest; b) 7, 30, and 65 days during bed rest; and c) 7 and 12 days after bed rest. Functional connectivity magnetic resonance imaging (FcMRI) analysis was performed to assess the connectivity of motor cortex in and out of bed rest. We found a decrease in motor cortex connectivity with vestibular cortex and the cerebellum from pre bed rest to in bed rest. We also used a battery of behavioral measures including the functional mobility test and computerized dynamic posturography collected before and after bed rest. We will report the preliminary results of analyses relating brain and behavior changes. Furthermore, we will also report the preliminary results of a spatial working memory task and vestibular stimulation during in and out of bed rest.

  19. Intrinsically organized resting state networks in the human spinal cord

    NARCIS (Netherlands)

    Kong, Y.; Eippert, F.; Beckmann, C.F.; Andersson, J.; Finsterbusch, J.; Büchel, C.; Tracey, I.; Brooks, J.C.W.

    2014-01-01

    Spontaneous fluctuations in functional magnetic resonance imaging (fMRI) signals of the brain have repeatedly been observed when no task or external stimulation is present. These fluctuations likely reflect baseline neuronal activity of the brain and correspond to functionally relevant resting-state

  20. Human resting extracellular heat shock protein 72 concentration decreases during the initial adaptation to exercise in a hot, humid environment

    Science.gov (United States)

    Marshall, Helen C.; Ferguson, Richard A.; Nimmo, Myra A.

    2006-01-01

    Heat shock protein (Hsp) 72 is a cytosolic protein that also is present in the circulation. Extracellular Hsp72 (eHsp72) is inducible by exercise and is suggested to act as a danger signal to the immune system. The adaptive response of eHsp72 to repeated exercise-heat exposures in humans remains to be determined. An intracellular animal study found a reduced Hsp72 response, with no change in resting levels, during heat stress after a single day of passive heat acclimation. The current study therefore tested whether adaptations in human eHsp72 levels would similarly occur 24 hours after a single exercise-heat exposure. Seven males completed cycle exercise (42.5% V̇O2peak for 2 hours) in a hot, humid environment (38°C, 60% relative humidity) on each of 2 consecutive days. Blood samples were obtained from an antecubital vein before exercise and 0 hours and 22 hours postexercise for the analysis of eHsp72. Exercise-heat stress resulted in enhanced eHsp72, with a similar absolute increase found on both days (day 1: 1.26 ng/mL [0.80 ng/mL]; day 2: 1.29 ng/mL [1.60 ng/mL]). Resting eHsp72 decreased from rest on day 1 to day 2's 22-hour postexercise sample (P < 0.05). It is suggested that the reduction in resting eHsp72 after 2 consecutive exercise-heat exposures is possibly due to an enhanced removal from the circulation, for either immunoregulatory functions, or for improved cellular stress tolerance in this initial, most stressful period of acclimation. PMID:16817318

  1. Response to muscular exercise following repeated simulated weightlessness

    Science.gov (United States)

    Convertino, V. A.; Kirby, C. R.; Karst, G. M.; Goldwater, D. J.

    1985-01-01

    The effects of 10-d 6-deg-head-down bed rest (BR1), 14 d of recovery, another 10 d bed rest (BR2), and another 14-d recovery on the cardiovascular response to a graded supine cycle ergometer test (4 min unloaded 60-rpm pedaling followed by 15-W/min increasing work load to volitional fatigue) are investigated experimentally in seven male nonsmokers of mean age 41 yrs, mean weight 80.2 kg, mean height 178 cm, and mean body fat content 22.3 percent. Ergometer tests are performed before BR1, after BR1 and BR2, and 14 d after BR2. The results are presented in tables, and it is found that the significantly decreased maximum-O2-uptake, gas-exchange-aerobic-threshold, and plasma-volume responses and the increased submaximal and maximal heart rates observed (relative to pre-BR1 levels) after BR1 and BR2 return to pre-BR1 values 14 d after BR2. It is inferred that 14 d of mild exercise are adequate for recovery from even repeated exposure to this type of simulated weightlessness.

  2. Scattered vignettes from repeated radiant exposure

    Science.gov (United States)

    Brooks, Lawrence D.

    2012-10-01

    In this presentation selected applications from the fields of Radiometry and Scattering are mingled with personal experiences to provide illumination upon William Wolfe's teaching, mentorship, insights and wit. Professor Wolfe served as the presenter's dissertation advisor from 1979-1982, but occasional industry interactions before and after that 3-year period provided the author a unique before-during-after sampling of this industry leader, author and teacher of Radiometry and applications of infrared technology to optical systems. The collection of selected topics begins with a brief review of the contribution of Max Planck, specifically his discovery of the blackbody radiation law in 1900. The assumption in Planck's equation not only provided the foundation of Quantum Physics, but the venerable equation itself today still serves as convenient basis for self-radiative source characterization in radiation transfer modeling for infrared systems. Subsequent topics of a more personal experience nature will include a successful application example of an advisor's counsel; an insider's life at the early days of Optical Sciences Annex; how history turned on an unlikely OSA scatter paper presentation; social optical engineering observations; the BRDF and development of the first Arizona computer-automated scatterometer; and a Swiss Army knife gift and metaphor. Via this review process, the author will not only reinforce existing Wolfe paradigms, but perhaps add some unique colors to the Wolfe spectrum, illustrating through one person's perspective of how over the decades Professor Wolfe has positively influenced the optical community in general, and one former Ph.D. student's career in particular.

  3. Repeat-until-success quantum repeaters

    Science.gov (United States)

    Bruschi, David Edward; Barlow, Thomas M.; Razavi, Mohsen; Beige, Almut

    2014-09-01

    We propose a repeat-until-success protocol to improve the performance of probabilistic quantum repeaters. Conventionally, these rely on passive static linear-optics elements and photodetectors to perform Bell-state measurements (BSMs) with a maximum success rate of 50%. This is a strong impediment for entanglement swapping between distant quantum memories. Every time a BSM fails, entanglement needs to be redistributed between the corresponding memories in the repeater link. The key ingredients of our scheme are repeatable BSMs. Under ideal conditions, these turn probabilistic quantum repeaters into deterministic ones. Under realistic conditions, our protocol too might fail. However, using additional threshold detectors now allows us to improve the entanglement generation rate by almost orders of magnitude, at a nominal distance of 1000 km, compared to schemes that rely on conventional BSMs. This improvement is sufficient to make the performance of our scheme comparable to the expected performance of some deterministic quantum repeaters.

  4. Bed Rest Muscular Atrophy

    Science.gov (United States)

    Greenleaf, John E.

    2000-01-01

    A major debilitating response from prolonged bed rest (BR) is muscle atrophy, defined as a "decrease in size of a part of tissue after full development has been attained: a wasting away of tissue as from disuse, old age, injury or disease". Part of the complicated mechanism for the dizziness, increased body instability, and exaggerated gait in patients who arise immediately after BR may be a result of not only foot pain, but also of muscular atrophy and associated reduction in lower limb strength. Also, there seems to be a close association between muscle atrophy and bone atrophy. A discussion of many facets of the total BR homeostatic syndrome has been published. The old adage that use determines form which promotes function of bone (Wolff's law) also applies to those people exposed to prolonged BR (without exercise training) in whom muscle atrophy is a consistent finding. An extreme case involved a 16-year-old boy who was ordered to bed by his mother in 1932: after 50 years in bed he had "a lily-white frame with limbs as thin as the legs of a ladder-back chair". These findings emphasize the close relationship between muscle atrophy and bone atrophy. In addition to loss of muscle mass during deconditioning, there is a significant loss of muscle strength and a decrease in protein synthesis. Because the decreases in force (strength) are proportionately greater than those in fiber size or muscle cross-sectional area, other contributory factors must be involved; muscle fiber dehydration may be important.

  5. Bed Rest Muscular Atrophy

    Science.gov (United States)

    Greenleaf, John E.

    2000-01-01

    A major debilitating response from prolonged bed rest (BR) is muscle atrophy, defined as a "decrease in size of a part of tissue after full development has been attained: a wasting away of tissue as from disuse, old age, injury or disease". Part of the complicated mechanism for the dizziness, increased body instability, and exaggerated gait in patients who arise immediately after BR may be a result of not only foot pain, but also of muscular atrophy and associated reduction in lower limb strength. Also, there seems to be a close association between muscle atrophy and bone atrophy. A discussion of many facets of the total BR homeostatic syndrome has been published. The old adage that use determines form which promotes function of bone (Wolff's law) also applies to those people exposed to prolonged BR (without exercise training) in whom muscle atrophy is a consistent finding. An extreme case involved a 16-year-old boy who was ordered to bed by his mother in 1932: after 50 years in bed he had "a lily-white frame with limbs as thin as the legs of a ladder-back chair". These findings emphasize the close relationship between muscle atrophy and bone atrophy. In addition to loss of muscle mass during deconditioning, there is a significant loss of muscle strength and a decrease in protein synthesis. Because the decreases in force (strength) are proportionately greater than those in fiber size or muscle cross-sectional area, other contributory factors must be involved; muscle fiber dehydration may be important.

  6. Cardiac atrophy in women following bed rest.

    Science.gov (United States)

    Dorfman, Todd A; Levine, Benjamin D; Tillery, Tommy; Peshock, Ronald M; Hastings, Jeff L; Schneider, Suzanne M; Macias, Brandon R; Biolo, Gianni; Hargens, Alan R

    2007-07-01

    Both chronic microgravity exposure and long-duration bed rest induce cardiac atrophy, which leads to reduced standing stroke volume and orthostatic intolerance. However, despite the fact that women appear to be more susceptible to postspaceflight presyncope and orthostatic hypotension than male astronauts, most previous high-resolution studies of cardiac morphology following microgravity have been performed only in men. Because female athletes have less physiological hypertrophy than male athletes, we reasoned that they also might have altered physiological cardiac atrophy after bed rest. Magnetic resonance imaging was performed in 24 healthy young women (32.1 +/- 4 yr) to measure left ventricular (LV) and right ventricular (RV) mass, volumes, and morphology accurately before and after 60 days of 6 degrees head-down tilt (HDT) bed rest. Subjects were matched and then randomly assigned to sedentary bed rest (controls, n = 8) or two treatment groups consisting of 1) exercise training using supine treadmill running within lower body negative pressure plus resistive training (n = 8), or 2) protein (0.45 g x kg(-1) x day(-1) increase) plus branched-chain amino acid (BCAA) (7.2 g/day) supplementation (n = 8). After sedentary bed rest without nutritional supplementation, there were significant reductions in LV (96 +/- 26 to 77 +/- 25 ml; P = 0.03) and RV volumes (104 +/- 33 to 86 +/- 25 ml; P = 0.02), LV (2.2 +/- 0.2 to 2.0 +/- 0.2 g/kg; P = 0.003) and RV masses (0.8 +/- 0.1 to 0.6 +/- 0.1 g/kg; P men (8.0%; Perhonen MA, Franco F, Lane LD, Buckey JC, Blomqvist Zerwekh JE, Peshock RM, Weatherall PT, Levine BD. J Appl Physiol 91: 645-653, 2001). In contrast, there were no significant reductions in LV or RV volumes in the exercise-trained group, and the length of the major axis was preserved. Moreover, there were significant increases in LV (1.9 +/- 0.4 to 2.3 +/- 0.3 g/kg; P women similar to men following sedentary 60 days HDT bed rest. However, exercise training and, to a

  7. Effects of Early and Late Rest Intervals on Performance and Overnight Consolidation of a Keyboard Sequence

    Science.gov (United States)

    Cash, Carla Davis

    2009-01-01

    Thirty-six nonmusicians practiced a five-element key-press sequence on a digital piano, repeating the sequence as quickly and accurately as possible during twelve 30-s practice blocks alternating with 30-s pauses. Twelve learners rested for 5 min between Blocks 3 and 4, another 12 learners rested for 5 min between Blocks 9 and 10, and the…

  8. Effects of Early and Late Rest Intervals on Performance and Overnight Consolidation of a Keyboard Sequence

    Science.gov (United States)

    Cash, Carla Davis

    2009-01-01

    Thirty-six nonmusicians practiced a five-element key-press sequence on a digital piano, repeating the sequence as quickly and accurately as possible during twelve 30-s practice blocks alternating with 30-s pauses. Twelve learners rested for 5 min between Blocks 3 and 4, another 12 learners rested for 5 min between Blocks 9 and 10, and the…

  9. Restful Web Service in Java%Java与Restful Web Service

    Institute of Scientific and Technical Information of China (English)

    袁赟

    2007-01-01

    近年来Web服务领域发生着翻天覆地的变化,继传统的XML-RPC风格的Web Service之后,一种新的风格,REST被应用于Web Service.本文主要介绍了Rest构架风格,以及现在Java开发Restful Web Service的主要方式,以及如何实现Restful Web Service的Java和Ajax客户端,最后介绍了Restful Web Service的描述语言WADL.

  10. RESTful Web Services at BNL

    Energy Technology Data Exchange (ETDEWEB)

    Casella, R.

    2011-06-14

    RESTful (REpresentational State Transfer) web services are an alternative implementation to SOAP/RPC web services in a client/server model. BNLs IT Division has started deploying RESTful Web Services for enterprise data retrieval and manipulation. Data is currently used by system administrators for tracking configuration information and as it is expanded will be used by Cyber Security for vulnerability management and as an aid to cyber investigations. This talk will describe the implementation and outstanding issues as well as some of the reasons for choosing RESTful over SOAP/RPC and future directions.

  11. Java与Restful Web Service

    Institute of Scientific and Technical Information of China (English)

    袁赟

    2007-01-01

    近年来Web服务领域发生着翻天覆地的变化,继传统的XML-RPC风格的Web Service之后,一种新的风格,REST被应用于Web Service.本文主要介绍了Rest构架风格,以及现在Java开发Restful Web Service的主要方式,以及如何实现Restful Web Service的Java和Ajax客户端,最后介绍了Restful Web Service的描述语言WADL.

  12. Clustering of resting state networks.

    Directory of Open Access Journals (Sweden)

    Megan H Lee

    Full Text Available BACKGROUND: The goal of the study was to demonstrate a hierarchical structure of resting state activity in the healthy brain using a data-driven clustering algorithm. METHODOLOGY/PRINCIPAL FINDINGS: The fuzzy-c-means clustering algorithm was applied to resting state fMRI data in cortical and subcortical gray matter from two groups acquired separately, one of 17 healthy individuals and the second of 21 healthy individuals. Different numbers of clusters and different starting conditions were used. A cluster dispersion measure determined the optimal numbers of clusters. An inner product metric provided a measure of similarity between different clusters. The two cluster result found the task-negative and task-positive systems. The cluster dispersion measure was minimized with seven and eleven clusters. Each of the clusters in the seven and eleven cluster result was associated with either the task-negative or task-positive system. Applying the algorithm to find seven clusters recovered previously described resting state networks, including the default mode network, frontoparietal control network, ventral and dorsal attention networks, somatomotor, visual, and language networks. The language and ventral attention networks had significant subcortical involvement. This parcellation was consistently found in a large majority of algorithm runs under different conditions and was robust to different methods of initialization. CONCLUSIONS/SIGNIFICANCE: The clustering of resting state activity using different optimal numbers of clusters identified resting state networks comparable to previously obtained results. This work reinforces the observation that resting state networks are hierarchically organized.

  13. Fuel utilization during exercise after 7 days of bed rest

    Science.gov (United States)

    Barrows, Linda H.; Harris, Bernard A.; Moore, Alan D.; Siconolfi, Steven F.

    1992-01-01

    Energy yield from carbohydrate, fat, and protein during physical activity is partially dependent on an individual's fitness level. Prolonged exposure to microgravity causes musculoskeletal and cardiovascular deconditioning; these adaptations may alter fuel utilization during space flight. Carbohydrate and fat metabolism during exercise were analyzed before and after 7 days of horizontal bed rest.

  14. The routine use of sublingual GTN with resting 99Tcm-tetrofosmin myocardial perfusion imaging.

    Science.gov (United States)

    Thorley, P J; Sheard, K L; Wright, D J; Sivananthan, U M

    1998-10-01

    Nitrates can be used to improve resting myocardial blood flow in patients with severe coronary artery disease. This may enhance tracer uptake during rest myocardial perfusion imaging. Recent studies using nitrates at rest have shown increased detection of reversible ischaemia in this patient group with the 201Tl and 99Tcm perfusion tracers MIBI and tetrofosmin. However, it is not always possible to assess the severity of coronary artery disease before the rest injection and therefore whether a patient would benefit from nitrate administration. To improve the sensitivity for the detection of reversible ischaemia and to avoid a repeat study with nitrates (especially in patients with 'fixed' defects), a protocol in which all patients routinely receive nitrates prior to the rest injection is required. This prospective study evaluated the effect of nitrate administration prior to rest imaging in a randomly selected group of patients. Thirty patients selected at random from routine referrals had stress, rest and rest + GTN tetrofosmin imaging on three separate days. Changes in reversibility between the rest and rest + GTN images were assessed both visually and using semi-quantitative analysis. Defects at stress were seen in 43 coronary artery territories, 33 of which were reversible at rest and 37 reversible at rest + GTN. Of these 43 defects, 82% demonstrated either increased or the same degree of reversibility at rest + GTN imaging compared to standard rest imaging. All defects with reduced reversibility at rest + GTN imaging (i.e. the remaining 18%) were, however, still reversible compared to the stress images. Some of this reduced reversibility may be due to attenuation artefacts. We conclude that the routine use of GTN with rest tetrofosmin imaging will result in increased detection of ischaemic areas with no loss of sensitivity or specificity.

  15. Digital repeat analysis; setup and operation.

    Science.gov (United States)

    Nol, J; Isouard, G; Mirecki, J

    2006-06-01

    Since the emergence of digital imaging, there have been questions about the necessity of continuing reject analysis programs in imaging departments to evaluate performance and quality. As a marketing strategy, most suppliers of digital technology focus on the supremacy of the technology and its ability to reduce the number of repeats, resulting in less radiation doses given to patients and increased productivity in the department. On the other hand, quality assurance radiographers and radiologists believe that repeats are mainly related to positioning skills, and repeat analysis is the main tool to plan training needs to up-skill radiographers. A comparative study between conventional and digital imaging was undertaken to compare outcomes and evaluate the need for reject analysis. However, digital technology still being at its early development stages, setting a credible reject analysis program became the major task of the study. It took the department, with the help of the suppliers of the computed radiography reader and the picture archiving and communication system, over 2 years of software enhancement to build a reliable digital repeat analysis system. The results were supportive of both philosophies; the number of repeats as a result of exposure factors was reduced dramatically; however, the percentage of repeats as a result of positioning skills was slightly on the increase for the simple reason that some rejects in the conventional system qualifying for both exposure and positioning errors were classified as exposure error. The ability of digitally adjusting dark or light images reclassified some of those images as positioning errors.

  16. Impact of housing condition on indoor-biting and indoor-resting Anopheles arabiensis density in a highland area, central Ethiopia.

    Science.gov (United States)

    Animut, Abebe; Balkew, Meshesha; Lindtjørn, Bernt

    2013-11-05

    Exposure of individuals to malaria infection may depend on their housing conditions as houses serve as biting and resting places of vectors. This study describes the association of housing conditions with densities of indoor-biting and indoor-resting Anopheles arabiensis in Hobe, Dirama and Wurib villages of a highland area in central Ethiopia. Data on housing conditions, including presence of house apertures, number of occupants and number and the type of domestic animal tethered inside, were collected. Indoor-biting mosquitoes were sampled using Centers for Disease Control (CDC) light traps and indoor-resting mosquitoes sampled with pyrethrum spray catches (PSCs) monthly for two years (July 2008 to June 2010). Female anophelines were identified to species and processed. Univariate and general linear estimating equation allowing for repeated measures were used to assess the contribution of housing conditions for indoor-biting and indoor-resting An. arabiensis. About 96% (4,597/4,788) of anophelines were caught inside residential houses. Nine anopheline species were identified, among which An. arabiensis was most prevalent (2,489; 52%). Vectors entering houses were higher in those situated at low (β = 4.475; 95% CI = 3.475-5.476; p windows (β = -0.570; 95% CI = -1.047-0.094; p =0.019) compared with those that have. Numbers of indoor-resting vectors were higher in those situated at low (β = 6.100; 95% CI = 4.571-7.629; p window, location at low and mid altitudes, were strong predictors of indoor exposure to An. arabiensis bite in a highland area of south-central Ethiopia.

  17. RESTful Java web services security

    CERN Document Server

    Enríquez, René

    2014-01-01

    A sequential and easy-to-follow guide which allows you to understand the concepts related to securing web apps/services quickly and efficiently, since each topic is explained and described with the help of an example and in a step-by-step manner, helping you to easily implement the examples in your own projects. This book is intended for web application developers who use RESTful web services to power their websites. Prior knowledge of RESTful is not mandatory, but would be advisable.

  18. [Rest for safety: which stakes?].

    Science.gov (United States)

    Mion, G; Ricouard, S

    2007-01-01

    In 2003 were promulgated the texts regulating rest and safety, in the USA (approved by the ACGME) and in France (January 9th, 2001 and September 14th, 2001). The institution of the "rest for safety", an eleven hours duration interruption of activity, immediately after a night-call, can be viewed as a progress in the search for safety. Several studies showed a link between excessive work hours and occurrence of medical incidents related to tiredness. However published data do not show a link between tiredness and patients endangering. The tiredness resulting from sleep deprivation and disturbances in circadian rhythms is a cumulative phenomenon erased by a period of rest. In spite of a large individual variability, tiredness increases anxiety scores, irritability, depression and it deteriorates cognitive performances. The concept of "prophylactic" rest considers that a subject cannot start, rested, a work if he did not sleep at least 5 hours the previous night, or 12 hours during the previous 48 hours. The second important aspect of the rest for safety is the long-term prevention of potential pathologies in medical staff, in particular burnout syndrome. In our profession, night calls are considered most stressful; the psychological stress related to anticipation and night context causes measurable cardiovascular disturbances in anesthesiologists. Shift-work sleep disorders may induce gastric ulcers, heart attacks, metabolic syndrome, depression and accidents related to somnolence. Long duration work-hours, accompanied by sleep deprivation, may double the risk of car accidents in junior physicians, in whom vigilance levels can compare with those of patients concerned by narcolepsy or with the cognitive disturbances induced by alcohol intoxication. Reduced work-hours improve vigilance and divide by three the rate of serious medical errors. True opportunities of sleep and control of sleep duration at the individual level could be suggested. The idea that taking the

  19. Java与Restful Web Service、

    Institute of Scientific and Technical Information of China (English)

    袁赟

    2007-01-01

    近年来Web服务领域发生着翻天覆地的变化,继传统的XML-RPC风格的Web Service之后,一种新的风格,REST被应用于WebService。本文主要介绍了Rest构架风格,以及现在Java开发Restful Web Service的主要方式,以及如何实现Resfful Web Service的Java和Ajax客户端,最后介绍了Restful Web Service的描述语言WADL。

  20. Quantum repeated games revisited

    CERN Document Server

    Frackiewicz, Piotr

    2011-01-01

    We present a scheme for playing quantum repeated 2x2 games based on the Marinatto and Weber's approach to quantum games. As a potential application, we study twice repeated Prisoner's Dilemma game. We show that results not available in classical game can be obtained when the game is played in the quantum way. Before we present our idea, we comment on the previous scheme of playing quantum repeated games.

  1. Effects of Artificial Gravity and Bed Rest on Spatial Orientation and Balance Control

    Science.gov (United States)

    Paloski, William H.; Moore, S. T.; Feiveson, A. H.; Taylor, L. C.

    2007-01-01

    While the vestibular system should be well-adapted to bed rest (a condition it experiences approximately 8/24 hrs each day), questions remain regarding the degree to which repeated exposures to the unusual gravito-inertial force environment of a short-radius centrifuge might affect central processing of vestibular information used in spatial orientation and balance control. Should these functions be impaired by intermittent AG, its feasibility as a counter-measure would be diminished. We, therefore, examined the effects of AG on spatial orientation and balance control in 15 male volunteers before and after 21 days of 6 HDT bed rest (BR). Eight of the subjects were treated with daily 1hr AG exposures (2.5g at the feet; 1.0g at the heart) aboard a short radius (3m) centrifuge, while the other seven served as controls (C). Spatial orientation was assessed by measures of ocular counter-rolling (OCR; rotation of the eye about the line of sight, an otolith-mediated reflex) and subjective visual vertical (SVV; perception of the spatial upright). Both OCR and SVV measurements were made with the subject upright, lying on their left sides, and lying on their right sides. OCR was measured from binocular eye orientation recordings made while the subjects fixated for 10s on a point target directly in front of the face at a distance of 1 m. SVV was assessed by asking subjects (in the dark) to adjust to upright (using a handheld controller) the orientation of a luminous bar randomly perturbed (15) to either side of the vertical meridian. Balance control performance was assessed using a computerized dynamic posturography (CDP) protocol similar to that currently required for all returning crew members. During each session, the subjects completed a combination of trials of sensory organization test (SOT) 2 (eyes closed, fixed platform) and SOT 5 (eyes closed, sway-referenced platform) with and without static and dynamic pitch plane head movements (plus or minus 20 deg., dynamic

  2. 29 CFR 785.18 - Rest.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Rest. 785.18 Section 785.18 Labor Regulations Relating to... INTERPRETATION NOT DIRECTLY RELATED TO REGULATIONS HOURS WORKED Application of Principles Rest and Meal Periods § 785.18 Rest. Rest periods of short duration, running from 5 minutes to about 20 minutes, are common in...

  3. Analysis list: REST [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available REST Blood,Breast,Digestive tract,Liver,Neural,Others,Pancreas,Pluripotent stem cel...l,Uterus + hg19 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/REST.1.tsv http://dbarchive.bioscienc...edbc.jp/kyushu-u/hg19/target/REST.5.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/REST.10.tsv h...ttp://dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/REST.Blood.tsv,http://dbarchi...ve.biosciencedbc.jp/kyushu-u/hg19/colo/REST.Breast.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/REST

  4. Repeated morphine treatment influences operant and spatial learning differentially

    Institute of Scientific and Technical Information of China (English)

    Mei-Na WANG; Zhi-Fang DONG; Jun CAO; Lin XU

    2006-01-01

    Objective To investigate whether repeated morphine exposure or prolonged withdrawal could influence operant and spatial learning differentially. Methods Animals were chronically treated with morphine or subjected to morphine withdrawal. Then, they were subjected to two kinds of learning: operant conditioning and spatial learning.Results The acquisition of both simple appetitive and cued operant learning was impaired after repeated morphine treatment. Withdrawal for 5 weeks alleviated the impairments. Single morphine exposure disrupted the retrieval of operant memory but had no effect on rats after 5-week withdrawal. Contrarily, neither chronic morphine exposure nor 5-week withdrawal influenced spatial learning task of the Morris water maze. Nevertheless, the retrieval of spatial memory was impaired by repeated morphine exposure but not by 5-week withdrawal. Conclusion These observations suggest that repeated morphine exposure can influence different types of learning at different aspects, implicating that the formation of opiate addiction may usurp memory mechanisms differentially.

  5. Effects of repeated exposure to high static magnetic fields during NMR imaging on the end point of reproduction and development in the animal model; Auswirkungen wiederholter Exposition mit starken statischen Magnetfeldern des MRI auf die Endpunkte Fortpflanzung und Entwicklung im Tiermodell

    Energy Technology Data Exchange (ETDEWEB)

    Winterhager, E.; Gruemmer, R.; Ladd, M.E.

    2011-12-15

    In the present study, the effects of repeated exposure to strong static magnetic fields up to a flux density of 7 Tesla on spermatogenesis in adult male mice as well as on pregnancy and embryogenesis in female mice were studied. In addition, the fertility of male and female mice which were exposed daily to these static magnetic fields throughout their entire embryonic development in utero was investigated. Six experimental groups were examined: (1) cage controls, (2) sham-exposed controls, (3) exposure at the bore entrance and (4) in the isocenter of a 1.5T MRI, (5) exposure at the bore entrance and (6) in the isocenter of a 7T MRI. Overall, 895 adult mice, 944 offspring, and 2007 embryos were analyzed in this study.

  6. Transfer of contaminants from surface to hands : experimental assessment of linearity of the exposure process, adherence to the skin, and area exposed during fixed pressure and repeated contact with surfaces contaminated with a powder

    NARCIS (Netherlands)

    Brouwer, D.H.; Kroese, R.; Hemmen, J.J. van

    1999-01-01

    Estimation of dermal exposure in the workplace resulting from contact with contaminated surfaces is important in risk assessment. Models have been developed to describe the process of exposure due to transfer, but for major input parameters - that is, contact area surface and adherence - defaults ar

  7. Reconfigurable multiport EPON repeater

    Science.gov (United States)

    Oishi, Masayuki; Inohara, Ryo; Agata, Akira; Horiuchi, Yukio

    2009-11-01

    An extended reach EPON repeater is one of the solutions to effectively expand FTTH service areas. In this paper, we propose a reconfigurable multi-port EPON repeater for effective accommodation of multiple ODNs with a single OLT line card. The proposed repeater, which has multi-ports in both OLT and ODN sides, consists of TRs, BTRs with the CDR function and a reconfigurable electrical matrix switch, can accommodate multiple ODNs to a single OLT line card by controlling the connection of the matrix switch. Although conventional EPON repeaters require full OLT line cards to accommodate subscribers from the initial installation stage, the proposed repeater can dramatically reduce the number of required line cards especially when the number of subscribers is less than a half of the maximum registerable users per OLT. Numerical calculation results show that the extended reach EPON system with the proposed EPON repeater can save 17.5% of the initial installation cost compared with a conventional repeater, and can be less expensive than conventional systems up to the maximum subscribers especially when the percentage of ODNs in lightly-populated areas is higher.

  8. Revisiting the TALE repeat.

    Science.gov (United States)

    Deng, Dong; Yan, Chuangye; Wu, Jianping; Pan, Xiaojing; Yan, Nieng

    2014-04-01

    Transcription activator-like (TAL) effectors specifically bind to double stranded (ds) DNA through a central domain of tandem repeats. Each TAL effector (TALE) repeat comprises 33-35 amino acids and recognizes one specific DNA base through a highly variable residue at a fixed position in the repeat. Structural studies have revealed the molecular basis of DNA recognition by TALE repeats. Examination of the overall structure reveals that the basic building block of TALE protein, namely a helical hairpin, is one-helix shifted from the previously defined TALE motif. Here we wish to suggest a structure-based re-demarcation of the TALE repeat which starts with the residues that bind to the DNA backbone phosphate and concludes with the base-recognition hyper-variable residue. This new numbering system is consistent with the α-solenoid superfamily to which TALE belongs, and reflects the structural integrity of TAL effectors. In addition, it confers integral number of TALE repeats that matches the number of bound DNA bases. We then present fifteen crystal structures of engineered dHax3 variants in complex with target DNA molecules, which elucidate the structural basis for the recognition of bases adenine (A) and guanine (G) by reported or uncharacterized TALE codes. Finally, we analyzed the sequence-structure correlation of the amino acid residues within a TALE repeat. The structural analyses reported here may advance the mechanistic understanding of TALE proteins and facilitate the design of TALEN with improved affinity and specificity.

  9. The Effects of Long Duration Bed Rest as a Spaceflight Analogue on Resting State Sensorimotor Network Functional Connectivity and Neurocognitive Performance

    Science.gov (United States)

    Cassady, K.; Koppelmans, V.; Yuan, P.; Cooke, K.; De Dios, Y.; Stepanyan, V.; Szecsy, D.; Gadd, N.; Wood, S.; Reuter-Lorenz, P.; hide

    2015-01-01

    Long duration spaceflight has been associated with detrimental alterations in human sensorimotor systems and neurocognitive performance. Prolonged exposure to a head-down tilt position during long duration bed rest can resemble several effects of the microgravity environment such as reduced sensory inputs, body unloading and increased cephalic fluid distribution. The question of whether microgravity affects other central nervous system functions such as brain functional connectivity and its relationship with neurocognitive performance is largely unknown, but of potential importance to the health and performance of astronauts both during and post-flight. The aims of the present study are 1) to identify changes in sensorimotor resting state functional connectivity that occur with extended bed rest exposure, and to characterize their recovery time course; 2) to evaluate how these neural changes correlate with neurocognitive performance. Resting-state functional magnetic resonance imaging (rsfMRI) data were collected from 17 male participants. The data were acquired through the NASA bed rest facility, located at the University of Texas Medical Branch (Galveston, TX). Participants remained in bed with their heads tilted down six degrees below their feet for 70 consecutive days. RsfMRI data were obtained at seven time points: 7 and 12 days before bed rest; 7, 50, and 65 days during bed rest; and 7 and 12 days after bed rest. Functional connectivity magnetic resonance imaging (fcMRI) analysis was performed to measure the connectivity of sensorimotor networks in the brain before, during, and post-bed rest. We found a decrease in left putamen connectivity with the pre- and post-central gyri from pre bed rest to the last day in bed rest. In addition, vestibular cortex connectivity with the posterior cingulate cortex decreased from pre to post bed rest. Furthermore, connectivity between cerebellar right superior posterior fissure and other cerebellar regions decreased from

  10. RESTful web services with Dropwizard

    CERN Document Server

    Dallas, Alexandros

    2014-01-01

    A hands-on focused step-by-step tutorial to help you create Web Service applications using Dropwizard. If you are a software engineer or a web developer and want to learn more about building your own Web Service application, then this is the book for you. Basic knowledge of Java and RESTful Web Service concepts is assumed and familiarity with SQL/MySQL and command-line scripting would be helpful.

  11. Analysis list: Rest [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Rest Muscle,Pluripotent stem cell + mm9 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Rest....1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Rest.5.tsv http://dbarchive.bios...ciencedbc.jp/kyushu-u/mm9/target/Rest.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Rest.Muscle....tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Rest.Pluripotent_stem_ce...ll.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Muscle.gml,http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Pluripotent_stem_cell.gml ...

  12. Recursive quantum repeater networks

    CERN Document Server

    Van Meter, Rodney; Horsman, Clare

    2011-01-01

    Internet-scale quantum repeater networks will be heterogeneous in physical technology, repeater functionality, and management. The classical control necessary to use the network will therefore face similar issues as Internet data transmission. Many scalability and management problems that arose during the development of the Internet might have been solved in a more uniform fashion, improving flexibility and reducing redundant engineering effort. Quantum repeater network development is currently at the stage where we risk similar duplication when separate systems are combined. We propose a unifying framework that can be used with all existing repeater designs. We introduce the notion of a Quantum Recursive Network Architecture, developed from the emerging classical concept of 'recursive networks', extending recursive mechanisms from a focus on data forwarding to a more general distributed computing request framework. Recursion abstracts independent transit networks as single relay nodes, unifies software layer...

  13. Rest requirements and rest management of personnel in shift work

    Energy Technology Data Exchange (ETDEWEB)

    Hammell, B.D. [PDG Environmental, Melbourne, FL (United States); Scheuerle, A. [Univ. of Texas, Houston, TX (United States)

    1995-12-31

    A difficulty-weighted shift assignment scheme is proposed for use in prolonged and strenuous field operations such as emergency response, site testing, and short term hazardous waste remediation projects. The purpose of the work rotation plan is to increase productivity, safety, and moral of workers. Job weighting is accomplished by assigning adjustments to the mental and physical intensity of the task, the protective equipment worn, and the climatic conditions. The plan is based on medical studies of sleep deprivation, the effects of rest adjustments, and programs to reduce sleep deprivation and normalize shift schedules.

  14. Examining prescribed rest as treatment for adolescents who are slow to recover from concussion.

    Science.gov (United States)

    Moser, Rosemarie Scolaro; Schatz, Philip; Glenn, Megan; Kollias, Kelly E; Iverson, Grant L

    2015-01-01

    Rest is a widely recommended treatment for concussion, but its utility is unclear following the acute stage of recovery. This study examined the effects of 1-week of prescribed rest in concussed adolescent athletes. Participants were 13 adolescent athletes with persistent symptoms following a concussion. More than three-quarters (77%) had self-reported ADHD, learning disability or two prior concussions. All completed ImPACT at another facility, but none completed a period of comprehensive rest prior to examination at a specialty practice. Three time points of test data were compared, to control for possible spontaneous recovery: Test 1 (external facility), Test 2 (before prescribed rest) and Test 3 (following prescribed rest). Repeated measures ANOVAs revealed a significant effect of prescribed rest on all ImPACT composite scores and the total symptom score. Post-hoc analyses revealed no significant differences between Time 1 and Time 2, whereas significant differences were present after prescribed rest. Following prescribed rest, having two or more reliably improved cognitive test scores or having improved symptoms was present in eight of the 13 patients (61.5%). A substantial percentage of adolescents with persistent symptoms following concussion showed improvement in symptoms and cognitive functioning following education, reassurance and 1-week of prescribed rest.

  15. Effects of Different Types of 3D Rest Frames on Reducing Cybersickness in a Virtual Environment

    Directory of Open Access Journals (Sweden)

    KyungHun Han

    2011-10-01

    Full Text Available A virtual environment (VE presents several kinds of sensory stimuli for creating a virtual reality. Some sensory stimuli presented in the VE have been reported to provoke cybersickness, which is caused by conflicts between sensory stimuli, especially conflicts between visual and vestibular sensations. Application of a rest frame has been known to be effective on reducing cybersickness by alleviating sensory conflict. The form and the way rest frames are presented in 3D VEs have different effects on reducing cybersickness. In this study, two different types of 3D rest frames were created. For verifying the rest frames' effects in reducing cybersickness, twenty subjects were exposed to two different rest frame conditions and a non-rest frame condition after an interval of three days in 3D VE. We observed the characteristic changes in the physiology of cybersickness in terms of autonomic regulation. Psychophysiological signals including EEG, EGG, and HRV were recorded and a simulator sickness questionnaire (SSQ was used for measuring the intensity of the sickness before and after the exposure to the different conditions. In the results, the SSQ was reduced significantly in the rest frame conditions. Psychophysiological responses changed significantly in the rest frame conditions compared to the non-rest frame condition. The results suggest that the rest frame conditions have condition-specific effects on reducing cybersickness by differentially alleviating aspects of visual and vestibular sensory conflicts in 3D VE.

  16. 75 FR 80746 - Interpretation of Rest Requirements

    Science.gov (United States)

    2010-12-23

    ... Federal Aviation Administration 14 CFR Part 135 Interpretation of Rest Requirements AGENCY: Federal... proposes to interpret the application of 14 CFR 135.263 and the rest requirements of Sec. 135.267(d) to... they will not receive the 10 hours of rest required in a 24-hour period by section 135.267(d...

  17. 78 FR 66865 - Interpretation of Rest Requirements

    Science.gov (United States)

    2013-11-07

    ... TRANSPORTATION Federal Aviation Administration 14 CFR Part 135 Interpretation of Rest Requirements AGENCY... application of certain rest requirements during on-demand operations. Section 346 of the FAA Modernization and... finalize the interpretation proposed in Docket No. FAA-2010-1259, relating to rest requirements, and...

  18. Repeated Witnessing of Conspecifics in Pain : Effects on Emotional Contagion

    NARCIS (Netherlands)

    Carrillo, Maria; Migliorati, Filippo; Bruls, Rune; Han, Yingying; Heinemans, Mirjam; Pruis, Ilanah; Gazzola, V.; Keysers, C.

    2015-01-01

    Witnessing of conspecifics in pain has been shown to elicit socially triggered freezing in rodents. It is unknown how robust this response is to repeated exposure to a cage-mate experiencing painful stimulation. To address this question, shock-experienced Observer rats repeatedly witnessed familiar

  19. The Pentapeptide Repeat Proteins

    Energy Technology Data Exchange (ETDEWEB)

    Vetting,M.; Hegde, S.; Fajardo, J.; Fiser, A.; Roderick, S.; Takiff, H.; Blanchard, J.

    2006-01-01

    The Pentapeptide Repeat Protein (PRP) family has over 500 members in the prokaryotic and eukaryotic kingdoms. These proteins are composed of, or contain domains composed of, tandemly repeated amino acid sequences with a consensus sequence of [S, T,A, V][D, N][L, F]-[S, T,R][G]. The biochemical function of the vast majority of PRP family members is unknown. The three-dimensional structure of the first member of the PRP family was determined for the fluoroquinolone resistance protein (MfpA) from Mycobacterium tuberculosis. The structure revealed that the pentapeptide repeats encode the folding of a novel right-handed quadrilateral {beta}-helix. MfpA binds to DNA gyrase and inhibits its activity. The rod-shaped, dimeric protein exhibits remarkable size, shape and electrostatic similarity to DNA.

  20. Physiological responses to repeated stress in individuals with high and low trait resilience.

    Science.gov (United States)

    Lü, Wei; Wang, Zhenhong; You, Xuqun

    2016-10-01

    This study examined individual differences in trait resilience in physiological recovery from, and physiological habituation to, repeated stress (i.e. public speaking). Eighty-two college students were categorized as either high (n=40) or low (n=42) on trait resilience, based on the scores of the Connor-Davidson Resilience Scale (CD-RISC). Subjective and physiological data were collected from participants across seven laboratory stages: baseline, stress anticipation 1, stress 1, post-stress 1, stress anticipation 2, stress 2, and post-stress 2. Results indicated that high-trait-resilient participants exhibited more complete heart rate (HR), systolic and diastolic blood pressure (SBP, DBP) recovery from the first and second stress anticipation exposures as compared to low-trait-resilient participants. High-trait-resilient participants demonstrated higher resting respiratory sinus arrhythmia (RSA) coupled with more complete RSA recovery from the first and second stress anticipation exposures as compared to their low-trait-resilient counterparts. Moreover, high-trait-resilient participants exhibited pronounced SBP and DBP habituation across two successive stress anticipation exposures, with greater decreases in SBP and DBP reactivity to recurrent stress anticipation as compared to the low-trait-resilient participants. These findings suggest an adaptive physiological response pattern to recurrent stress in high-trait-resilient individuals. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Repeating the Past

    Science.gov (United States)

    Moore, John W.

    1998-05-01

    As part of the celebration of the Journal 's 75th year, we are scanning each Journal issue from 25, 50, and 74 years ago. Many of the ideas and practices described are so similar to present-day "innovations" that George Santayana's adage (1) "Those who cannot remember the past are condemned to repeat it" comes to mind. But perhaps "condemned" is too strong - sometimes it may be valuable to repeat something that was done long ago. One example comes from the earliest days of the Division of Chemical Education and of the Journal.

  2. Exercise thermoregulation with bed rest, confinement, and immersion deconditioning

    Science.gov (United States)

    Greenleaf, J. E.

    1997-01-01

    Altered thermoregulation following exposure to prolonged (12-14 days) of bed rest and 6 hr of head-down thermoneutral water immersion in humans, and cage confinement (8 weeks) in male, mongrel dogs resulted in occasional increased core temperature (Tcore) at rest, but consistent "excessive" increase in Tcore during submaximal exercise. This excessive increase in Tcore in nonexercising and exercising subjects was independent of the mode (isometric or isotonic) of exercise training during bed rest, and was associated with the consistent hypovolemia in men but not in women taking estrogen supplementation (1.25 mg premarin/ day) which restored plasma volume during bed rest to ambulatory control levels. Post-bed rest exercise sweating (evaporative heat loss) was unchanged or higher than control levels; however, calculated tissue heat conductance was significantly lower in men, and forearm venoconstriction was greater (venous volume was reduced) in women during exercise after bed rest. Because sweating appeared proportional to the increased level of Tcore, these findings suggest that one major factor for the excessive hyperthermia is decreased core to periphery heat conduction. Exercising dogs respond like humans with excessive increase in both rectal (Tre) and exercising muscle temperatures (Tmu) after confinement and, after eight weeks of exercise training on a treadmill following confinement, they had an attenuated rate of increase of Tre even below ambulatory control levels. Intravenous infusion of glucose also attenuated not only the rise in Tre during exercise in normal dogs, but also the excessive rise in Tre and exercising Tmu after confinement. Oral glucose also appeared to reduce the rate of increase in excessive Tre in men after immersion deconditioning. There was a greater rate of rise in Tcore in two cosmonauts during supine submaximal exercise (65% VO2 max) on the fifth recovery day after the 115-day Mir 18 mission. Thus, the excessive rise in core

  3. Exposure to polycyclic aromatic hydrocarbons among never smokers in Golestan Province, Iran, an area of high incidence of esophageal cancer – a cross-sectional study with repeated measurement of urinary 1-OHPG in two seasons

    Directory of Open Access Journals (Sweden)

    Farhad eIslami

    2012-02-01

    Full Text Available Studies have suggested a possible role of polycyclic aromatic hydrocarbons (PAHs in the etiology of esophageal cancer in Golestan Province, Iran, where incidence of this cancer is very high. In order to investigate the patterns of non-smoking related exposure to PAHs in Golestan, we conducted a cross-sectional study collecting questionnaire data, genotyping polymorphisms related to PAH metabolism, and measuring levels of 1-hydroxypyrene glucuronide (1-OHPG, a PAH metabolite, in urine samples collected in two seasons from the same group of 111 randomly-selected never-smoking women. Beta-coefficients for correlations between 1-OHPG as dependent variable and other variables were calculated using linear regression models. The creatinine-adjusted 1-OHPG levels in both winter and summer samples were approximately 110 μmol/molCr (P for seasonal difference= 0.40. In winter, red meat intake (β= 0.208; P= 0.03, processed meat intake (β= 0.218; P= 0.02 and GSTT1-02 polymorphism (null genotype: β= 0.228; P= 0.02 showed significant associations with 1-OHPG levels, while CYP1B1-07 polymorphism (GG versus AA+GA genotypes: β= –0.256; P= 0.008 showed an inverse association. In summer, making bread at home (>weekly versus never: β= 0.203; P= 0.04, second-hand smoke (exposure to ≥3 cigarettes versus no exposure: β= 0.254; P= 0.01, and GSTM1-02 null genotype (β= 0.198; P= 0.04 showed significant associations with 1-OHPG levels, but GSTP1-02 polymorphism (CT+TT versus CC: β= –0.218; P= 0.03 showed an inverse association. This study confirms high exposure of the general population in Golestan to PAHs and suggests that certain foods, cooking methods, and genetic polymorphisms increase exposure to PAHs.

  4. All-optical repeater.

    Science.gov (United States)

    Silberberg, Y

    1986-06-01

    An all-optical device containing saturable gain, saturable loss, and unsaturable loss is shown to transform weak, distorted optical pulses into uniform standard-shape pulses. The proposed device performs thresholding, amplification, and pulse shaping as required from an optical repeater. It is shown that such a device could be realized by existing semiconductor technology.

  5. Bidirectional Manchester repeater

    Science.gov (United States)

    Ferguson, J.

    1980-01-01

    Bidirectional Manchester repeater is inserted at periodic intervals along single bidirectional twisted pair transmission line to detect, amplify, and transmit bidirectional Manchester 11 code signals. Requiring only 18 TTL 7400 series IC's, some line receivers and drivers, and handful of passive components, circuit is simple and relatively inexpensive to build.

  6. Intrasellar Symptomatic Salivary Gland Rest

    Directory of Open Access Journals (Sweden)

    Chih-Hao Chen

    2007-05-01

    Full Text Available Ectopic salivary gland tissue in sellar turcica is frequently observed in microscopic examination at autopsy. This tissue is considered clinically silent. Only 2 symptomatic cases have been previously reported. Here we report a 28-year-old woman presenting with galactorrhea and hyperprolactinemia. Magnetic resonance imaging revealed a 6×5-mm nodule in the posterior aspect of the pituitary gland. This nodule showed isointensity on T1- and T2-weighted images and less enhancement on post-contrast T1-weighted images. Transsphenoidal exploration revealed a cystic lesion within the pituitary gland, which consisted of a grayish gelatinous content. The pathologic examination confirmed the diagnosis of salivary gland rest.

  7. An adequate interset rest period for strength recovery during a common isokinetic test.

    Science.gov (United States)

    Blazquez, Ivan N; Warren, Barbara L; O'Hanlon, Ann M; Silvestri, Lynette R

    2013-07-01

    Isokinetic testing is used in rehabilitation settings on a regular basis; yet, there is a lack of consistency in rest period usage among protocols. Furthermore, the allotment of rest periods has been arbitrary (e.g., 30, 60, 90 seconds or more). This investigation examines the work:rest ratio as an effective method of standardizing rest periods in isokinetic testing. The purpose of this study was to establish an adequate rest period that would allow reproducibility of strength during a common isokinetic strength test. Twenty-seven healthy college-aged men (age, 23 ± 3.8 years; body weight, 79.54 ± 11.09 kg) were tested on 5 separate occasions: 2 familiarization sessions and 3 experimental sessions. Each subject performed a knee extension/flexion isokinetic strength protocol (Cybex NORM; Lumex, Inc., Ronkonkoma, NY, USA) to determine peak torque by performing 5 maximal reciprocal repetitions at each ascending velocity of 60, 180, and 300°·s. Work:rest ratios of 1:3, 1:8, and 1:12 were counterbalanced between sets. A 3 × 3 repeated measures analysis of variance was used to analyze the data. A significance level of α ≤ 0.05 was used for all tests. There was no significant difference in either knee extension or knee flexion peak torque when comparing work:rest ratios. These findings suggest that a 1:3 work:rest ratio is sufficient during a common isokinetic strength test.

  8. Cardiovascular risk factors in children after repeat doses of antenatal glucocorticoids: an RCT

    National Research Council Canada - National Science Library

    McKinlay, Christopher J D; Cutfield, Wayne S; Battin, Malcolm R; Dalziel, Stuart R; Crowther, Caroline A; Harding, Jane E

    2015-01-01

    .... We assessed whether exposure to repeat antenatal betamethasone increased risk factors for later cardiometabolic disease in children whose mothers participated in the Australasian Collaborative Trial...

  9. Repeated in utero and lactational 2,3,7,8-tetrachlorodibenzo-p-dioxin exposure affects male gonads in offspring, leading to sex ratio changes in F2 progeny.

    Science.gov (United States)

    Ikeda, Masahiko; Tamura, Masashi; Yamashita, Junko; Suzuki, Chinatsu; Tomita, Takako

    2005-08-15

    The effects of in utero and lactational 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on the reproductive system of male rat offspring (F1) and the sex ratio of the subsequent generation (F2) were examined. Female Holtzman rats were gavaged with an initial loading dose of 400 ng/kg TCDD prior to mating, followed by weekly maintenance doses of 80 ng/kg during mating, pregnancy, and the lactation period. Maternal exposure to TCDD had no significant effects on fetus/pup (F1) mortality, litter size, or sex ratio on gestation day (GD) 20 or postnatal day (PND) 2. The TCDD concentration in maternal livers and adipose tissue on GD20 was 1.21 and 1.81 ng/kg, respectively, and decreased at weaning to 0.72 in the liver and 0.84 in the adipose tissue. In contrast, the TCDD concentration in pup livers was 1.32 ng/kg on PND2 and increased to 1.80 ng/kg at weaning. Ventral prostate weight of male offspring was significantly decreased by TCDD exposure on PND28 and 120 compared with that of controls. Weight of the testes, cauda epididymides, and seminal vesicle, and sperm number in the cauda epididymis were not changed by TCDD exposure at PND120. TCDD- or vehicle-exposed male offspring were mated with unexposed females. The sex ratio (percentage of male pups) of F2 offspring was significantly reduced in the TCDD-exposed group compared with controls. These results suggest that in utero and lactational TCDD exposures affect the development of male gonads in offspring (F1), leading to changes in the sex ratio of the subsequent generation (F2).

  10. Increased Brain Activation for Foot Movement During 70-Day 6 Deg Head-Down Bed Rest (HDBR): Evidence from Functional Magnetic Resonance Imaging (fMRI)

    Science.gov (United States)

    Yuan, P.; Koppelmans, V.; Cassady, K.; Cooke, K.; De Dios, Y. E.; Stepanyan, V.; Szecsy, D.; Gadd, N.; Wood, S. J.; Reuter-Lorenz, P. A.; hide

    2015-01-01

    Bed rest has been widely used as a simulation of weightlessness in studying the effects of microgravity exposure on human physiology and cognition. Changes in muscle function and functional mobility have been reported to be associated with bed rest. Understanding the effect of bed rest on neural control of movement would provide helpful information for spaceflight. In the current study, we evaluated how the brain activation for foot movement changed as a function of bed rest. Eighteen healthy men (aged 25 to 39 years) participated in this HDBR study. They remained continuously in the 6deg head-down tilt position for 70 days. Functional MRI was acquired during 1-Hz right foot tapping, and repeated at 7 time points: 12 days pre-, 8 days pre-, 7 days in-, 50 days in-, 70 days in-, 8 days post-, and 12 days post- HDBR. In all 7 sessions, we observed increased activation in the left motor cortex, right cerebellum and right occipital cortex during foot movement blocks compared to rest. Compared to the pre-HDBR baseline (1st and 2nd sessions), foot movement-induced activation in the left hippocampus increased during HDBR. This increase emerged in the 4th session, enlarged in the 5th session, and remained significant in the 6th and 7th sessions. Furthermore, increased activation relative to the baseline in left precuneus was observed in the 5th, 6th and 7th sessions. In addition, in comparison with baseline, increased activation in the left cerebellum was found in the 4th and 5th sessions, whereas increased activation in the right cerebellum was observed in the 4th, 6th and 7th sessions. No brain region exhibited decreased activation during bed rest compared to baseline. The increase of foot movement related brain activation during HDBR suggests that in a long-term head-down position, more neural control is needed to accomplish foot movements. This change required a couple of weeks to develop in HDBR (between 3rd and 4th sessions), and did not return to baseline even 12

  11. Resting Heart Rate and Auditory Evoked Potential

    Directory of Open Access Journals (Sweden)

    Simone Fiuza Regaçone

    2015-01-01

    Full Text Available The objective of this study was to evaluate the association between rest heart rate (HR and the components of the auditory evoked-related potentials (ERPs at rest in women. We investigated 21 healthy female university students between 18 and 24 years old. We performed complete audiological evaluation and measurement of heart rate for 10 minutes at rest (heart rate monitor Polar RS800CX and performed ERPs analysis (discrepancy in frequency and duration. There was a moderate negative correlation of the N1 and P3a with rest HR and a strong positive correlation of the P2 and N2 components with rest HR. Larger components of the ERP are associated with higher rest HR.

  12. Duct Leakage Repeatability Testing

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Iain [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sherman, Max [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2014-01-01

    Duct leakage often needs to be measured to demonstrate compliance with requirements or to determine energy or Indoor Air Quality (IAQ) impacts. Testing is often done using standards such as ASTM E1554 (ASTM 2013) or California Title 24 (California Energy Commission 2013 & 2013b), but there are several choices of methods available within the accepted standards. Determining which method to use or not use requires an evaluation of those methods in the context of the particular needs. Three factors that are important considerations are the cost of the measurement, the accuracy of the measurement and the repeatability of the measurement. The purpose of this report is to evaluate the repeatability of the three most significant measurement techniques using data from the literature and recently obtained field data. We will also briefly discuss the first two factors. The main question to be answered by this study is to determine if differences in the repeatability of these tests methods is sufficient to indicate that any of these methods is so poor that it should be excluded from consideration as an allowed procedure in codes and standards.

  13. The cause of ischaemic nocturnal rest pain

    DEFF Research Database (Denmark)

    Jelnes, Rolf; Bülow, J; Tønnesen, K H

    1988-01-01

    of symptomatology. In two limbs, with a normal peripheral circulation, blood flow decreased by 8 +/- 7%. In five limbs with arterial insufficiency, but no rest pain, blood flow decreased by 16 +/- 8% and in eight limbs with ischaemic nocturnal rest pain blood flow was reduced by 32 +/- 12% during sleep....... It is concluded that nocturnal hypotension is a major factor in the production of nocturnal ischaemic rest pain....

  14. Pro REST API development with nodejs

    CERN Document Server

    Doglio, Fernando

    2015-01-01

    Pro REST API Development with Node.js is your guide to managing and understanding the full capabilities of successful REST development. API design is a hot topic in the programming world, but not many resources exist for developers to really understand how you can leverage the advantages. This book will provide a brief background on REST and the tools it provides (well known and not so well known). Understand how there is more to REST than just JSON and URLs. You will then cover and compare the maintained modules currently available in the npm community, including Express, Restify, Vatican,

  15. Repeated-sprint ability and aerobic fitness.

    Science.gov (United States)

    Thébault, Nicolas; Léger, Luc A; Passelergue, Philippe

    2011-10-01

    The purpose of this study was to reinvestigate the relationship between aerobic fitness and fatigue indices of repeated-sprint ability (RSA), with special attention to methodological normalization. Soldiers were divided into low (n = 10) and high (n = 9) fitness groups according to a preset maximal aerobic speed (MAS) of 17 km·h(-1) (∼60 ml O2·kg(-1)·min) measured with the University of Montreal Track Test (UMTT). Subjects' assessment included the RSA test (3 sets of 5 40-m sprints with 1-minute rest between sprints and 1.5 minutes between sets), a 40-m sprint (criterion test used in the computation of fatigue indices for the RSA test), strength and power measurement of the lower limbs, and the 20-m shuttle run test (20-m SRT) and the UMTT, which are measures of maximal aerobic power. The highest correlation with the RSA fatigue indices was obtained with the 20-m SRT (r = 0.90, p = 0.0001, n = 19), a test with 180° direction changes and accelerations and decelerations. The lower correlation (r = 0.66, p repeated sprints and achieved better recovery between series. A MAS of at least 17 km·h(-1) favors constant and high speed level during repeated sprints. From a practical point of view, a high aerobic fitness is a precious asset in counteracting fatigue in sports with numerous sprint repetitions.

  16. Rest boosts the long-term retention of spatial associative and temporal order information.

    Science.gov (United States)

    Craig, Michael; Dewar, Michaela; Della Sala, Sergio; Wolbers, Thomas

    2015-09-01

    People retain more new verbal episodic information for at least 7 days if they rest for a few minutes after learning than if they attend to new information. It is hypothesized that rest allows for superior consolidation of new memories. In rodents, rest periods promote hippocampal replay of a recently travelled route, and this replay is thought to be critical for memory consolidation and subsequent spatial navigation. If rest boosts human memory by promoting hippocampal replay/consolidation, then the beneficial effect of rest should extend to complex (hippocampal) memory tasks, for example, tasks probing associations and sequences. We investigated this question via a virtual reality route memory task. Healthy young participants learned two routes to a 100% criterion. One route was followed by a 10-min rest and the other by a 10-min spot the difference game. For each learned route, participants performed four delayed spatial memory tests probing: (i) associative (landmark-direction) memory, (ii) cognitive map formation, (iii) temporal (landmark) order memory, and (iv) route memory. Tests were repeated after 7 days to determine any long-term effects. No effect of rest was detected in the route memory or cognitive map tests, most likely due to ceiling and floor effects, respectively. Rest did, however, boost retention in the associative memory and temporal order memory tests, and this boost remained for at least 7 days. We therefore demonstrate that the benefit of rest extends to (spatial) associative and temporal order memory in humans. We hypothesise that rest allows superior consolidation/hippocampal replay of novel information pertaining to a recently learned route, thus boosting new memories over the long term.

  17. Neuro-mechanical determinants of repeated treadmill sprints - Usefulness of an “hypoxic to normoxic recovery” approach

    Science.gov (United States)

    Girard, Olivier; Brocherie, Franck; Morin, Jean-Benoit; Millet, Grégoire P.

    2015-01-01

    To improve our understanding of the limiting factors during repeated sprinting, we manipulated hypoxia severity during an initial set and examined the effects on performance and associated neuro-mechanical alterations during a subsequent set performed in normoxia. On separate days, 13 active males performed eight 5-s sprints (recovery = 25 s) on an instrumented treadmill in either normoxia near sea-level (SL; FiO2 = 20.9%), moderate (MH; FiO2 = 16.8%) or severe normobaric hypoxia (SH; FiO2 = 13.3%) followed, 6 min later, by four 5-s sprints (recovery = 25 s) in normoxia. Throughout the first set, along with distance covered [larger sprint decrement score in SH (−8.2%) compared to SL (−5.3%) and MH (−7.2%); P sprint of the subsequent normoxic set, the distance covered (99.6, 96.4, and 98.3% of sprint 1 in SL, MH, and SH, respectively), the main kinetic (mean vertical, horizontal, and resultant forces) and kinematic (contact time and step frequency) variables as well as surface electromyogram of quadriceps and plantar flexor muscles were fully recovered, with no significant difference between conditions. Despite differing hypoxic severity levels during sprints 1–8, performance and neuro-mechanical patterns did not differ during the four sprints of the second set performed in normoxia. In summary, under the circumstances of this study (participant background, exercise-to-rest ratio, hypoxia exposure), sprint mechanical performance and neural alterations were largely influenced by the hypoxia severity in an initial set of repeated sprints. However, hypoxia had no residual effect during a subsequent set performed in normoxia. Hence, the recovery of performance and associated neuro-mechanical alterations was complete after resting for 6 min near sea level, with a similar fatigue pattern across conditions during subsequent repeated sprints in normoxia. PMID:26441679

  18. Repeated morphine pretreatment reduces glutamatergic synaptic potentiation in the nucleus accumbens induced by acute morphine exposure%慢性吗啡预处理减弱急性吗啡对伏隔核谷氨酸能突触传递的影响

    Institute of Scientific and Technical Information of China (English)

    吴晓杰; 张静; 魏春玲; 刘志强; 任维

    2012-01-01

    Repeated exposure to morphine leads to the addiction, which influences its clinical application seriously. The glutamatergic projection from prefrontal cortex (PFC) to the nucleus accumbens (Nac) plays an important role in rewarding effects. It is still unknown whether morphine exposure changes PFC-Nac synaptic transmission. To address this question, in vivo field excitatory post-synaptic potentials (fEPSPs) induced by electric stimulating PFC-Nac projection fibers were recorded to evaluate the effect of acute morphine exposure (10 mg/kg, s.c.) on glutamatergic synaptic transmission in Nac shell of repeated saline/morphine pretreated rats. It was showed that acute morphine exposure enhanced fEPSP amplitude and reduced paired-pulse ratio (PPR) in saline pretreated rats, which could be reversed by following naloxone injection (1 mg/kg, I.p.), an opiate receptor antagonist. However, repeated morphine pretreatment significantly inhibited both the enhancement of fEPSP amplitude and reduction of PPR induced by acute morphine exposure. Those results indicate that the initial morphine exposure enhances PFC-Nac synaptic transmission by pre-synaptic mechanisms, whereas morphine pretreatment occludes this effect.%吗啡长期作用后会产生成瘾(addiction),严重影响其临床应用.前额叶(prefrontal cortex,PFC)投射至伏隔核(nucleus accumbens,NAc)的谷氨酸能突触对奖赏效应有重要的调节作用,但该突触在吗啡成瘾中的具体作用尚不完全清楚.为探讨PFC至NAc的谷氨酸能突触在成瘾形成过程中的具体作用及其机制,本研究利用成年大鼠在体记录的方式,记录电刺激PFC至NAc谷氨酸能传入纤维引起的NAc壳区场兴奋性突触后电位(filed excitatory postsynaptic potential,fEPSP),观察慢性吗啡/盐水预处理后依次急性皮下注射吗啡及腹腔注射纳络酮对fEPSP幅值和配对脉冲比率(paired-pulse ratio,PPR)的影响.结果显示,与基础fEPSP相比,慢性盐水预处理组急

  19. Cognitive Rest: An Integrated Literature Review

    Science.gov (United States)

    Schneider, Kathleen H.

    2016-01-01

    Cognitive rest has been suggested as a treatment for school athletes who have sustained a concussion, but the concept has rarely been defined. The purpose of this article is to provide a comprehensive definition of cognitive rest, based on an integrative literature review. The method of synthesis was guided by Avant and Walker's concept analysis…

  20. International Standardization of Bed Rest Standard Measures

    Science.gov (United States)

    Cromwell, Ronita L.

    2010-01-01

    This slide presentation gives an overview of the standardization of bed rest measures. The International Countermeasures Working Group attempted to define and agree internationally on standard measurements for spaceflight based bed rest studies. The group identified the experts amongst several stakeholder agencys. It included information on exercise, muscle, neurological, psychological, bone and cardiovascular measures.

  1. Repeatability of Cryogenic Multilayer Insulation

    Science.gov (United States)

    Johnson, W. L.; Vanderlaan, M.; Wood, J. J.; Rhys, N. O.; Guo, W.; Van Sciver, S.; Chato, D. J.

    2017-01-01

    Due to the variety of requirements across aerospace platforms, and one off projects, the repeatability of cryogenic multilayer insulation has never been fully established. The objective of this test program is to provide a more basic understanding of the thermal performance repeatability of MLI systems that are applicable to large scale tanks. There are several different types of repeatability that can be accounted for: these include repeatability between multiple identical blankets, repeatability of installation of the same blanket, and repeatability of a test apparatus. The focus of the work in this report is on the first two types of repeatability. Statistically, repeatability can mean many different things. In simplest form, it refers to the range of performance that a population exhibits and the average of the population. However, as more and more identical components are made (i.e. the population of concern grows), the simple range morphs into a standard deviation from an average performance. Initial repeatability testing on MLI blankets has been completed at Florida State University. Repeatability of five GRC provided coupons with 25 layers was shown to be +/- 8.4 whereas repeatability of repeatedly installing a single coupon was shown to be +/- 8.0. A second group of 10 coupons have been fabricated by Yetispace and tested by Florida State University, through the first 4 tests, the repeatability has been shown to be +/- 16. Based on detailed statistical analysis, the data has been shown to be statistically significant.

  2. Spacing Effect: SHP2 Phosphatase Regulates Resting Intervals Between Learning Trials in Long-Term Memory Induction

    OpenAIRE

    Pagani, Mario R.; Oishi, Kimihiko; Gelb, Bruce D.; Zhong, Yi

    2009-01-01

    A common property of long-term memory (LTM) induction is the requirement for repeated training sessions spaced over time. The phenomena of better memory being formed with resting intervals between training sessions is called the spacing effect, for which the underlying molecular and neural bases are largely unknown. Our study reveals that the duration of resting intervals required for inducing LTM can be regulated by activity levels of the protein tyrosine phosphatase corkscrew (CSW) in Droso...

  3. Safety of Repeated Yttrium-90 Radioembolization

    Energy Technology Data Exchange (ETDEWEB)

    Lam, Marnix G. E. H.; Louie, John D. [Stanford University School of Medicine, Division of Interventional Radiology (United States); Iagaru, Andrei H.; Goris, Michael L. [Stanford University School of Medicine, Division of Nuclear Medicine (United States); Sze, Daniel Y., E-mail: dansze@stanford.edu [Stanford University School of Medicine, Division of Interventional Radiology (United States)

    2013-10-15

    Purpose: Repeated radioembolization (RE) treatments carry theoretically higher risk of radiation-induced hepatic injury because of the liver's cumulative memory of previous exposure. We performed a retrospective safety analysis on patients who underwent repeated RE. Methods: From 2004 to 2011, a total of 247 patients were treated by RE. Eight patients (5 men, 3 women, age range 51-71 years) underwent repeated treatment of a targeted territory, all with resin microspheres (SIR-Spheres; Sirtex, Lane Cove, Australia). Adverse events were graded during a standardized follow-up. In addition, the correlation between the occurrence of RE-induced liver disease (REILD) and multiple variables was investigated in univariate and multivariate analyses in all 247 patients who received RE. Results: Two patients died shortly after the second treatment (at 84 and 107 days) with signs and symptoms of REILD. Both patients underwent whole liver treatment twice (cumulative doses 3.08 and 2.66 GBq). The other 6 patients demonstrated only minor toxicities after receiving cumulative doses ranging from 2.41 to 3.88 GBq. All patients experienced objective tumor responses. In the whole population, multifactorial analysis identified three risk factors associated with REILD: repeated RE (p = 0.036), baseline serum total bilirubin (p = 0.048), and baseline serum aspartate aminotransferase (p = 0.043). Repeated RE proved to be the only independent risk factor for REILD in multivariate analysis (odds ratio 9.6; p = 0.002). Additionally, the administered activity per target volume (in GBq/L) was found to be an independent risk factor for REILD, but only in whole liver treatments (p = 0.033). Conclusion: The risk of REILD appears to be elevated for repeated RE. Objective tumor responses were observed, but establishment of safety limits will require improvement in dosimetric measurement and prediction.

  4. Serum level of high-sensitivity C-reactive protein in a rabbit model of atherosclerosis following repeated long-term exposure to positive acceleration%重复长时间正加速度暴露动脉粥样硬化家兔模型血清超敏C-反应蛋白的变化

    Institute of Scientific and Technical Information of China (English)

    罗慧兰; 陈勇胜

    2012-01-01

    BACKGROUND: Serum levels of high-sensitivity C-reactive protein (hs-CRP) can be used to predict cardiovascular injury.OBJECTIVE: To investigate the serum levels of hs-CRP in a rabbit model of atherosclerosis following repeated long-termexposure to positive acceleration and to predict the risk of cardiovascular injury.METHODS: Twenty-four New Zealand purebred rabbits were randomly divided into a positive acceleration group and a controlgroup. Rabbits in the positive acceleration group were exposed to +4 g rotation for 20 seconds with an acceleration of 1 g/s. Therotation interval was 5 minutes and totally three rotations were daily performed for 3 days per week. 0.5 g rotation was addedevery week, and by week 4, +6 g rotation was added, and the exposure lasted for 40 seconds.RESULTS AND CONCLUSION: Exposure to positive acceleration yielded significant effects on serum level of hs-CRP in rabbitswith atherosclerosis compared with before exposure (P 0.05). The interaction between exposure to positive acceleration and exposure time also did not produce significanteffects on serum level of hs-CRP (P > 0.05). Hyperplastic foam cells in the aortic tunica intima and the superficial layer of mediaincreased with the prolongation of exposure to positive acceleration. Repeated long-term exposure to positive acceleration maylead to a long-term high serum level of hs-CRP in rabbits.%背景:血清超敏C-反应蛋白的水平能够预测心血管损伤.目的:探讨重复正加速度暴露时动脉粥样硬化模型家兔血清超敏C-反应蛋白的变化与心血管损伤的风险预测.方法:将24 只新西兰纯种兔随机等分为正加速度组和对照组.正加速度组兔先在+4 g 水平(持续20 s,增长率为1 g/s)下暴露,旋转间隔时间为5 min,连续旋转3 次,每周3 d.每周增加0.5 g,至第4 周时增加至+6 g,持续暴露40 s.差异也无显著性意义(P > 0.05).兔主动脉内膜下及中膜浅层增生的泡沫细胞量随正加速度暴露的延长

  5. The Effects of Long Duration Bed Rest on Brain Functional Connectivity and Sensorimotor Functioning

    Science.gov (United States)

    Cassady, K.; Koppelmans, V.; De Dios, Y.; Stepanyan, V.; Szecsy, D.; Gadd, N.; Wood, S.; Reuter-Lorenz, P.; Castenada, R. Riascos; Kofman, I.; Bloomberg, J.; Mulavara, A; Seidler, R.

    2016-01-01

    Long duration spaceflight has been associated with detrimental alterations in human sensorimotor functioning. Prolonged exposure to a head-down tilt (HDT) position during long duration bed rest can resemble several effects of the microgravity environment such as reduced sensory inputs, body unloading and increased cephalic fluid distribution. The question of whether microgravity affects other central nervous system functions such as brain functional connectivity and its relationship with behavior is largely unknown, but of importance to the health and performance of astronauts both during and post-flight. In the present study, we investigate the effects of prolonged exposure to HDT bed rest on resting state brain functional connectivity and its association with behavioral changes in 17 male participants. To validate that our findings were not due to confounding factors such as time or task practice, we also acquired resting state functional magnetic resonance imaging (rs-fMRI) and behavioral measurements from 14 normative control participants at four time points. Bed rest participants remained in bed with their heads tilted down six degrees below their feet for 70 consecutive days. Rs-fMRI and behavioral data were obtained at seven time points averaging around: 12 and 8 days prior to bed rest; 7, 50, and 70 days during bed rest; and 8 and 12 days after bed rest. 70 days of HDT bed rest resulted in significant increases in functional connectivity during bed rest followed by a reversal of changes in the post bed rest recovery period between motor cortical and somatosensory areas of the brain. In contrast, decreases in connectivity were observed between temporoparietal regions. Furthermore, post-hoc correlation analyses revealed a significant relationship between motor-somatosensory network connectivity and standing balance performance changes; participants that exhibited the greatest increases in connectivity strength showed the least deterioration in postural

  6. Comparison of the Effects of Seated, Supine, and Walking Interset Rest Strategies on Work Rate.

    Science.gov (United States)

    Ouellette, Kristen A; Brusseau, Timothy A; Davidson, Lance E; Ford, Candus N; Hatfield, Disa L; Shaw, Janet M; Eisenman, Patricia A

    2016-12-01

    Ouellette, KA, Brusseau, TA, Davidson, LE, Ford, CN, Hatfield, DL, Shaw, JM, and Eisenman, PA. Comparison of the effects of seated, supine, and walking interset rest strategies on work rate. J Strength Cond Res 30(12): 3396-3404, 2016-The idea that an upright posture should be maintained during the interset rest periods of training sessions is pervasive. The primary aim of this study was to determine differences in work rate associated with 3 interset rest strategies. Male and female members of the CrossFit community (male n = 5, female n = 10) were recruited to perform a strenuous training session designed to enhance work capacity that involved both cardiovascular and muscular endurance exercises. The training session was repeated on 3 separate occasions to evaluate 3 interset rest strategies, which included lying supine on the floor, sitting on a flat bench, and walking on a treadmill (0.67 m·s). Work rate was calculated for each training session by summing session joules of work and dividing by the time to complete the training session (joules of work per second). Data were also collected during the interset rest periods (heart rate [HR], respiratory rate [RR], and volume of oxygen consumed) and were used to explain why one rest strategy may positively impact work rate compared with another. Statistical analyses revealed significant differences (p ≤ 0.05) between the passive and active rest strategies, with the passive strategies allowing for improved work rate (supine = 62.77 ± 7.32, seated = 63.66 ± 8.37, and walking = 60.61 ± 6.42 average joules of work per second). Results also suggest that the passive strategies resulted in superior HR, RR, and oxygen consumption recovery. In conclusion, work rate and physiological recovery were enhanced when supine and seated interset rest strategies were used compared with walking interset rest.

  7. Differential deployment of REST and CoREST promotes glial subtype specification and oligodendrocyte lineage maturation.

    Directory of Open Access Journals (Sweden)

    Joseph J Abrajano

    Full Text Available BACKGROUND: The repressor element-1 (RE1 silencing transcription factor/neuron-restrictive silencer factor (REST/NRSF is a master transcriptional regulator that binds to numerous genomic RE1 sites where it acts as a molecular scaffold for dynamic recruitment of modulatory and epigenetic cofactors, including corepressor for element-1-silencing transcription factor (CoREST. CoREST also acts as a hub for various cofactors that play important roles in epigenetic remodeling and transcriptional regulation. While REST can recruit CoREST to its macromolecular complex, CoREST complexes also function at genomic sites independently of REST. REST and CoREST perform a broad array of context-specific functions, which include repression of neuronal differentiation genes in neural stem cells (NSCs and other non-neuronal cells as well as promotion of neurogenesis. Despite their involvement in multiple aspects of neuronal development, REST and CoREST are not believed to have any direct modulatory roles in glial cell maturation. METHODOLOGY/PRINCIPAL FINDINGS: We challenged this view by performing the first study of REST and CoREST in NSC-mediated glial lineage specification and differentiation. Utilizing ChIP on chip (ChIP-chip assays, we identified distinct but overlapping developmental stage-specific profiles for REST and CoREST target genes during astrocyte (AS and oligodendrocyte (OL lineage specification and OL lineage maturation and myelination, including many genes not previously implicated in glial cell biology or linked to REST and CoREST regulation. Amongst these factors are those implicated in macroglial (AS and OL cell identity, maturation, and maintenance, such as members of key developmental signaling pathways and combinatorial transcription factor codes. CONCLUSIONS/SIGNIFICANCE: Our results imply that REST and CoREST modulate not only neuronal but also glial lineage elaboration. These factors may therefore mediate critical developmental processes

  8. Stability of dental waxes following repeated heatings.

    Science.gov (United States)

    Kotsiomiti, E; McCabe, J F

    1995-02-01

    The flow and strength properties of dental waxes were examined following excessive and repeated heatings of the materials. For one product, the flow at 40 +/- 0.5 degrees C was reduced by 25.3% following heating above 200 degrees C. A decrease of the elastic modulus at 20 +/- 1 degree C by approximately 66% was observed in some cases after the heating temperature had been increased to 300 degrees C. Property variations were related to compositional changes, which were investigated by infrared spectoscopy and thermal analysis. Exposure of dental waxes to temperatures higher than 200 degrees C, particularly if it is repeated, may affect the composition and properties, resulting in inferior materials.

  9. Elegants ja eklektika - Rest Art / Lylian Meister

    Index Scriptorium Estoniae

    Meister, Lylian, 1966-

    2007-01-01

    Tallinnas Mustika keskuses asuvas sisustussalongis Rest Art pakutavast. Asjade müümise kõrval pakutakse kodudele ja hotellidele-restoranidele terviklahendusi. Salongi kujundas Kard Männil. 4 värv. vaadet

  10. RESTful Java patterns and best practices

    CERN Document Server

    Mehta, Bhakti

    2014-01-01

    This book is aimed at novice developers who want to gain insights into building RESTful services and improve productivity, as well as for advanced developers who want to delve into more complicated topics.

  11. Elegants ja eklektika - Rest Art / Lylian Meister

    Index Scriptorium Estoniae

    Meister, Lylian, 1966-

    2007-01-01

    Tallinnas Mustika keskuses asuvas sisustussalongis Rest Art pakutavast. Asjade müümise kõrval pakutakse kodudele ja hotellidele-restoranidele terviklahendusi. Salongi kujundas Kard Männil. 4 värv. vaadet

  12. Rest Areas in the Western United States

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Rest areas in the western United States. Data was collected from various data sources including georeferenced locations obtained from other agencies, digitizied...

  13. Is bed rest following embryo transfer necessary?

    Science.gov (United States)

    Sharif, K; Afnan, M; Lashen, H; Elgendy, M; Morgan, C; Sinclair, L

    1998-03-01

    To evaluate the effect of no bed rest following ET on the results of an IVF program. Historical cohort-control study. A University-based assisted conception unit. One thousand and nineteen (1019) IVF cycles were performed at our unit from June 1994 to August 1996. The historical control consisted of all the 19,697 IVF cycles reported in the United Kingdom national database from April 1994 to March 1995. No bed rest following ET in our patients. Pregnancy rate (PR) and clinical PR per cycles started and per ET procedure. The clinical PR per ET was significantly higher in our patients than in the national data (30% versus 22.9%), as was the clinical PR per cycle (23.5% versus 18.6%). The implantation rate in our patients was 17.2%. The favorable PR in our patients despite no bed rest following ET suggests the bed rest is not necessary.

  14. Resting heart rate estimation using PIR sensors

    Science.gov (United States)

    Kapu, Hemanth; Saraswat, Kavisha; Ozturk, Yusuf; Cetin, A. Enis

    2017-09-01

    In this paper, we describe a non-invasive and non-contact system of estimating resting heart rate (RHR) using a pyroelectric infrared (PIR) sensor. This infrared system monitors and records the chest motion of a subject using the analog output signal of the PIR sensor. The analog output signal represents the composite motion due to inhale-exhale process with magnitude much larger than the minute vibrations of heartbeat. Since the acceleration of the heart activity is much faster than breathing the second derivative of the PIR sensor signal monitoring the chest of the subject is used to estimate the resting heart rate. Experimental results indicate that this ambient sensor can measure resting heart rate with a chi-square significance level of α = 0.05 compared to an industry standard PPG sensor. This new system provides a low cost and an effective way to estimate the resting heart rate, which is an important biological marker.

  15. USAJOBS Job Opportunity Announcements (JOA) REST API

    Data.gov (United States)

    Office of Personnel Management — This REST-based API is designed to support lightweight Federal Job Opportunity Announcement (JOA) content consumption by consumers. It is anticipated that this API...

  16. REST advanced research topics and practical applications

    CERN Document Server

    Wilde, Erik; Alarcon, Rosa

    2014-01-01

    This book serves as a starting point for people looking for a deeper principled understanding of REST, its applications, its limitations, and current research work in the area and as an architectural style. The authors focus on applying REST beyond Web applications (i.e., in enterprise environments), and in reusing established and well-understood design patterns. The book examines how RESTful systems can be designed and deployed, and what the results are in terms of benefits and challenges encountered in the process. This book is intended for information and service architects and designers who are interested in learning about REST, how it is applied, and how it is being advanced.

  17. ReSTful OSGi Web Applications Tutorial

    Science.gov (United States)

    Shams, Khawaja; Norris, Jeff

    2008-01-01

    This slide presentation accompanies a tutorial on the ReSTful (Representational State Transfer) web application. Using Open Services Gateway Initiative (OSGi), ReST uses HTTP protocol to enable developers to offer services to a diverse variety of clients: from shell scripts to sophisticated Java application suites. It also uses Eclipse for the rapid development, the Eclipse debugger, the test application, and the ease of export to production servers.

  18. Ising Model Reprogramming of a Repeat Protein's Equilibrium Unfolding Pathway.

    Science.gov (United States)

    Millership, C; Phillips, J J; Main, E R G

    2016-05-08

    Repeat proteins are formed from units of 20-40 aa that stack together into quasi one-dimensional non-globular structures. This modular repetitive construction means that, unlike globular proteins, a repeat protein's equilibrium folding and thus thermodynamic stability can be analysed using linear Ising models. Typically, homozipper Ising models have been used. These treat the repeat protein as a series of identical interacting subunits (the repeated motifs) that couple together to form the folded protein. However, they cannot describe subunits of differing stabilities. Here we show that a more sophisticated heteropolymer Ising model can be constructed and fitted to two new helix deletion series of consensus tetratricopeptide repeat proteins (CTPRs). This analysis, showing an asymmetric spread of stability between helices within CTPR ensembles, coupled with the Ising model's predictive qualities was then used to guide reprogramming of the unfolding pathway of a variant CTPR protein. The designed behaviour was engineered by introducing destabilising mutations that increased the thermodynamic asymmetry within a CTPR ensemble. The asymmetry caused the terminal α-helix to thermodynamically uncouple from the rest of the protein and preferentially unfold. This produced a specific, highly populated stable intermediate with a putative dimerisation interface. As such it is the first step in designing repeat proteins with function regulated by a conformational switch. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  19. Repeat remote ischaemic pre-conditioning for improved cardiovascular function in humans: A systematic review

    Directory of Open Access Journals (Sweden)

    J. Epps

    2016-06-01

    Conclusion: Repeated RIPC exposure has produced evidence of improvements in endothelial dependent vasodilation, ulcer healing and blood pressure but no benefit in non-endothelial dependent vasodilation, cutaneous vascular conductance or cardiorespiratory fitness. The optimal delivery of RIPC remains unclear, but at least 3 or preferably 4, 5 min exposures appears to be most beneficial, at least for reducing blood pressure. Aside from those undertaking cardiac surgery, other study populations with endothelial dysfunction may benefit from repeat exposure to RIPC.

  20. Expansion of protein domain repeats.

    Directory of Open Access Journals (Sweden)

    Asa K Björklund

    2006-08-01

    Full Text Available Many proteins, especially in eukaryotes, contain tandem repeats of several domains from the same family. These repeats have a variety of binding properties and are involved in protein-protein interactions as well as binding to other ligands such as DNA and RNA. The rapid expansion of protein domain repeats is assumed to have evolved through internal tandem duplications. However, the exact mechanisms behind these tandem duplications are not well-understood. Here, we have studied the evolution, function, protein structure, gene structure, and phylogenetic distribution of domain repeats. For this purpose we have assigned Pfam-A domain families to 24 proteomes with more sensitive domain assignments in the repeat regions. These assignments confirmed previous findings that eukaryotes, and in particular vertebrates, contain a much higher fraction of proteins with repeats compared with prokaryotes. The internal sequence similarity in each protein revealed that the domain repeats are often expanded through duplications of several domains at a time, while the duplication of one domain is less common. Many of the repeats appear to have been duplicated in the middle of the repeat region. This is in strong contrast to the evolution of other proteins that mainly works through additions of single domains at either terminus. Further, we found that some domain families show distinct duplication patterns, e.g., nebulin domains have mainly been expanded with a unit of seven domains at a time, while duplications of other domain families involve varying numbers of domains. Finally, no common mechanism for the expansion of all repeats could be detected. We found that the duplication patterns show no dependence on the size of the domains. Further, repeat expansion in some families can possibly be explained by shuffling of exons. However, exon shuffling could not have created all repeats.

  1. DWI Repeaters and Non-Repeaters: A Comparison.

    Science.gov (United States)

    Weeber, Stan

    1981-01-01

    Discussed how driving-while-intoxicated (DWI) repeaters differed signigicantly from nonrepeaters on 4 of 23 variables tested. Repeaters were more likely to have zero or two dependent children, attend church frequently, drink occasionally and have one or more arrests for public intoxication. (Author)

  2. To Repeat or Not to Repeat a Course

    Science.gov (United States)

    Armstrong, Michael J.; Biktimirov, Ernest N.

    2013-01-01

    The difficult transition from high school to university means that many students need to repeat (retake) 1 or more of their university courses. The authors examine the performance of students repeating first-year core courses in an undergraduate business program. They used data from university records for 116 students who took a total of 232…

  3. Brain Vulnerability to Repeated Blast Overpressure and Polytrauma

    Science.gov (United States)

    2013-11-01

    discrimination procedures were developed, refined and implemented to test visual acuity and visually based cognitive performance and reaction time. Telemetric...exposure: The shock tube consists of a 2.5 ft long compression chamber that is separated from a 15 ft long expansion chamber by polyester Mylar...single BOP (figs 8 & 9) or 2 BOPs separated by 24 hr (not shown), closely coupled repeated BOP exposure increased reaction times (fig 11

  4. Increased Brain Activation for Dual Tasking with 70-Days Head-Down Bed Rest

    Science.gov (United States)

    Yuan, Peng; Koppelmans, Vincent; Reuter-Lorenz, Patricia A.; De Dios, Yiri E.; Gadd, Nichole E.; Wood, Scott J.; Riascos, Roy; Kofman, Igor S.; Bloomberg, Jacob J.; Mulavara, Ajitkumar P.; Seidler, Rachael D.

    2016-01-01

    Head-down tilt bed rest (HDBR) has been used as a spaceflight analog to simulate the effects of microgravity exposure on human physiology, sensorimotor function, and cognition on Earth. Previous studies have reported that concurrent performance of motor and cognitive tasks can be impaired during space missions. Understanding the consequences of HDBR for neural control of dual tasking may possibly provide insight into neural efficiency during spaceflight. In the current study, we evaluated how dual task performance and the underlying brain activation changed as a function of HDBR. Eighteen healthy men participated in this study. They remained continuously in the 6° head-down tilt position for 70 days. Functional MRI for bimanual finger tapping was acquired during both single task and dual task conditions, and repeated at 7 time points pre-, during- and post-HDBR. Another 12 healthy males participated as controls who did not undergo HDBR. A widely distributed network involving the frontal, parietal, cingulate, temporal, and occipital cortices exhibited increased activation for dual tasking and increased activation differences between dual and single task conditions during HDBR relative to pre- or post-HDBR. This HDBR-related brain activation increase for dual tasking implies that more neurocognitive control is needed for dual task execution during HDBR compared to pre- and post-HDBR. We observed a positive correlation between pre-to-post HDBR changes in dual-task cost of reaction time and pre-to-post HDBR change in dual-task cost of brain activation in several cerebral and cerebellar regions. These findings could be predictive of changes in dual task processing during spaceflight. PMID:27601982

  5. 重复、长时间正加速度对动脉粥样硬化家兔模型血管内分泌功能的影响%Effect of repeated and prolonged +Gz exposure on endocrine function of vessel in a rabbit model of atherosclerosis

    Institute of Scientific and Technical Information of China (English)

    罗惠兰; 陈勇胜; 谢放; 孙津津

    2012-01-01

    目的 观察重复、长时间正加速度(+Gz)对动脉粥样硬化家兔模型血管内分泌功能的影响.方法 健康雄性新西兰白兔24只,建立动脉粥样硬化模型后随机分为对照组(不进行+Gz暴露,n=12)和+Gz暴露组(n=12).分别于4、8、12周后处死两组动物(每个时间点4只),采用放射免疫及生物化学法测定静脉血的血管紧张素Ⅱ(AngⅡ)、内皮素(ET)含量及血管内皮细胞的血红素氧化酶-1(HO-1)活力、内源性一氧化碳(CO)浓度及环磷酸鸟苷(cGMP)含量,并对主动脉内膜进行电镜观察.结果 随+Gz暴露时间的延长,实验室兔静脉血AngⅡ、ET及血管内皮细胞HO-1、CO、cGMP含量均显著增高(P<0.05),但暴露至第12周时已不再增加;对照组上述指标无明显变化(P=0.05).对照组动脉内膜下及中膜浅层的泡沫细胞及胶原含量仅见少量增加,而+Gz暴露8、12周后主动脉内膜下及中膜浅层可见大量增生的泡沫细胞,间质胶原纤维含量明显增加.结论 重复、长时间+Gz暴露会诱发AngⅡ和ET的产生,但也会增加HO-1、CO、cGMP的分泌,对血管免受进一步损伤可能具有潜在的保护作用.%Objective To investigate the effect of repeated and prolonged +Gz exposure on endocrine function of vessel in a rabbit model of atherosclerosis. Methods Twenty-four male New Zealand white rabbits were used to establish the model of atherosclerosis, and then randomly divided into control group and +Gz exposure group (12 each). Animals in control group underwent no +Gz exposure, while those in +Gz exposure group underwent +Gz exposure for 4, 8, and 12 weeks respectively (4 animals at each time point), and 4 animals from each group were sacrificed at each time point. The levels of angiotensin II (Ang II), endothelin (ET), heme oxygenase-1 (HO-l), carbon monoxide (CO) and cyclic guanosine-3', 5'-monophosphate (cGMP) were measured by radioimmunoassay and biochemical method, and the ultrastructure of

  6. REST and CoREST modulate neuronal subtype specification, maturation and maintenance.

    Directory of Open Access Journals (Sweden)

    Joseph J Abrajano

    Full Text Available BACKGROUND: The repressor element-1 silencing transcription factor/neuron-restrictive silencer factor (REST/NRSF is a master regulator of neuronal gene expression. REST functions as a modular scaffold for dynamic recruitment of epigenetic regulatory factors including its primary cofactor, the corepressor for element-1-silencing transcription factor (CoREST, to genomic loci that contain the repressor element-1 (RE1 binding motif. While REST was initially believed to silence RE1 containing neuronal genes in neural stem cells (NSCs and non-neuronal cells, emerging evidence shows an increasingly complex cell type- and developmental stage-specific repertoire of REST target genes and functions that include regulation of neuronal lineage maturation and plasticity. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we utilized chromatin immunoprecipitation on chip (ChIP-chip analysis to examine REST and CoREST functions during NSC-mediated specification of cholinergic neurons (CHOLNs, GABAergic neurons (GABANs, glutamatergic neurons (GLUTNs, and medium spiny projection neurons (MSNs. We identified largely distinct but overlapping profiles of REST and CoREST target genes during neuronal subtype specification including a disproportionately high percentage that are exclusive to each neuronal subtype. CONCLUSIONS/SIGNIFICANCE: Our findings demonstrate that the differential deployment of REST and CoREST is an important regulatory mechanism that mediates neuronal subtype specification by modulating specific gene networks responsible for inducing and maintaining neuronal subtype identity. Our observations also implicate a broad array of factors in the generation of neuronal diversity including but not limited to those that mediate homeostasis, cell cycle dynamics, cell viability, stress responses and epigenetic regulation.

  7. Nifty Nines and Repeating Decimals

    Science.gov (United States)

    Brown, Scott A.

    2016-01-01

    The traditional technique for converting repeating decimals to common fractions can be found in nearly every algebra textbook that has been published, as well as in many precalculus texts. However, students generally encounter repeating decimal numerals earlier than high school when they study rational numbers in prealgebra classes. Therefore, how…

  8. Nifty Nines and Repeating Decimals

    Science.gov (United States)

    Brown, Scott A.

    2016-01-01

    The traditional technique for converting repeating decimals to common fractions can be found in nearly every algebra textbook that has been published, as well as in many precalculus texts. However, students generally encounter repeating decimal numerals earlier than high school when they study rational numbers in prealgebra classes. Therefore, how…

  9. All-photonic quantum repeaters

    Science.gov (United States)

    Azuma, Koji; Tamaki, Kiyoshi; Lo, Hoi-Kwong

    2015-01-01

    Quantum communication holds promise for unconditionally secure transmission of secret messages and faithful transfer of unknown quantum states. Photons appear to be the medium of choice for quantum communication. Owing to photon losses, robust quantum communication over long lossy channels requires quantum repeaters. It is widely believed that a necessary and highly demanding requirement for quantum repeaters is the existence of matter quantum memories. Here we show that such a requirement is, in fact, unnecessary by introducing the concept of all-photonic quantum repeaters based on flying qubits. In particular, we present a protocol based on photonic cluster-state machine guns and a loss-tolerant measurement equipped with local high-speed active feedforwards. We show that, with such all-photonic quantum repeaters, the communication efficiency scales polynomially with the channel distance. Our result paves a new route towards quantum repeaters with efficient single-photon sources rather than matter quantum memories. PMID:25873153

  10. Regional cerebral blood flow during rest and skilled hand movements by xenon-133 inhalation and emission computerized tomography

    DEFF Research Database (Denmark)

    Lauritzen, M; Henriksen, L; Lassen, N A

    1981-01-01

    Regional cerebral blood flow (CBF) was studied in 16 normal adult volunteers during rest and in 10 the study was repeated during skilled hand movements. A fast-rotating ("dynamic"), single-photon emission computerized tomograph (ECT) with four detector heads was used. Xenon-133 was inhaled over a 1...

  11. Exercise countermeasures for bed-rest deconditioning

    Science.gov (United States)

    Greenleaf, John (Editor)

    1993-01-01

    The purpose for this 30-day bed rest study was to investigate the effects of short-term, high intensity isotonic and isokinetic exercise training on maintenance of working capacity (peak oxygen uptake), muscular strength and endurance, and on orthostatic tolerance, posture and gait. Other data were collected on muscle atrophy, bone mineralization and density, endocrine analyses concerning vasoactivity and fluid-electrolyte balance, muscle intermediary metabolism, and on performance and mood of the subjects. It was concluded that: The subjects maintained a relatively stable mood, high morale, and high esprit de corps throughout the study. Performance improved in nearly all tests in almost all the subjects. Isotonic training, as opposed to isokinetic exercise training, was associated more with decreasing levels of psychological tension, concentration, and motivation; and improvement in the quality of sleep. Working capacity (peak oxygen uptake) was maintained during bed rest with isotonic exercise training; it was not maintained with isokinetic or no exercise training. In general, there was no significant decrease in strength or endurance of arm or leg muscles during bed rest, in spite of some reduction in muscle size (atrophy) of some leg muscles. There was no effect of isotonic exercise training on orthostasis, since tilt-table tolerance was reduced similarly in all three groups following bed rest. Bed rest resulted in significant decreases of postural stability and self-selected step length, stride length, and walking velocity, which were not influenced by either exercise training regimen. Most pre-bed rest responses were restored by the fourth day of recovery.

  12. Dose and effect of inhaled ozone in resting versus exercising human subjects: comparison with resting rats

    Science.gov (United States)

    Dose and effect of inhaled ozone in resting versus exercising human subjects: comparison with resting rats Authors: Gary E. Hatch, John McKee, James Brown, Bill McDonnell, Elston Seal, Joleen Soukup, Ralph Slade, Kay Crissman and Robert Devlin, National Health and Environmental...

  13. REST in practice Hypermedia and systems architecture

    CERN Document Server

    Webber, Jim; Robinson, Ian

    2010-01-01

    Why don't typical enterprise projects go as smoothly as projects you develop for the Web? Does the REST architectural style really present a viable alternative for building distributed systems and enterprise-class applications? In this insightful book, three SOA experts provide a down-to-earth explanation of REST and demonstrate how you can develop simple and elegant distributed hypermedia systems by applying the Web's guiding principles to common enterprise computing problems. You'll learn techniques for implementing specific Web technologies and patterns to solve the needs of a typical com

  14. Cervical Spinal Injury from Repeated Exposures to Sustained Acceleration.

    Science.gov (United States)

    1999-02-01

    herniated disks, vertebral osteoarthritis and calcification. It was noted that pilots in good physical condition were at lower risk for acquired vertebral... osteoarthritis ; and, 4. Occurrence of a vertebral pain syndrome, associated with vertebral disk degeneration with the development of concomitant... physiotherapy session during weekly activities; 4. Physiotherapy before and after aerobatics flight mission and air combat maneuvers; and, 5. A

  15. A Preliminary Evaluation of Repeated Exposure for Depersonalization and Derealization

    Science.gov (United States)

    Weiner, Elliot; McKay, Dean

    2013-01-01

    Dissociative symptoms including depersonalization and derealization are commonly experienced by individuals suffering from panic disorder or posttraumatic stress disorder (PTSD). Few studies have been published investigating the specific treatment of these symptoms in individuals diagnosed with panic disorder or PTSD, despite evidence that the…

  16. The Effects of Repeated Low-Dose Sarin Exposure

    Science.gov (United States)

    2006-01-01

    and slight enzyme that breaks down the cholinergic neurotransmitter ataxia . It has been observed in rats and mice that (NT) acetylcholine (ACh). The...minutes) Latency to the first movement (see)_ Total # of rears (C) Total # of grooming episodes (C) Arousal: (R) (choose one) I. Very low (little or...description: (D) (choose one) 1. No movement 2. Normal 3. Impairment a. Uncoordinated movement ( ataxia ) b. Walking on toes c. Splayed hind limbs d

  17. Repeated Acute Oral Exposure to Cannabis sativa Impaired ...

    African Journals Online (AJOL)

    olayemitoyin

    cannabis on cortico-hippocampal neuronal architecture and morphology, and consequently cognitive ... number of illicit drug consumption has unfortunately .... (40×60×50 cm) and the floor was divided into 25 equal .... Showing: normal granulation and highly populated dentate granule cells in Saline; pyknotic soma and.

  18. Heat production and heat loss responses to cold water immersion after 35 days horizontal bed rest.

    Science.gov (United States)

    Mekjavic, Igor B; Kounalakis, Stylianos N; Keramidas, Michail E; Biolo, Gianni; Narici, Marco; Eiken, Ola

    2012-05-01

    Bed rest is a terrestrial experimental analogue of unloading experienced during exposure to microgravity. Such unloading causes atrophy predominantly of the postural muscles, especially those of the lower limbs. We tested the hypothesis that 35 d horizontal bed rest alters thermoregulatory responses of subjects (N = 10) immersed in 15 degrees C water, particularly the heat produced by the shivering tremor of the skeletal muscles. Before and after bed rest we measured the thickness of the gastrocnemius medialis (GM), vastus lateralis (VL), tibialis anterior (TA), and biceps brachii (BB) muscles by ultrasonography. During the immersions, we monitored rectal and skin temperatures, heat flux, heart rate, and oxygen uptake. After bed rest, muscle thickness decreased significantly by 12.2 +/- 8.8% and 8.0 +/- 9.1% in the GM and VL, respectively. No changes were observed in the TA and BB muscles. The 35-d bed rest caused a significant reduction in aerobic power, as reflected in maximal oxygen uptake. There were no significant differences in any of the observed thermoregulatory responses between the pre- and post-bed rest immersions. Cardiovascular and muscular deconditioning had no effect on the heat production and heat loss responses. Due to the significant reduction in the mass of the muscles in the lower limbs, concomitant with no change in heat production, we conclude that leg muscles do not play a significant role in shivering thermogenesis.

  19. Rheological modelling of physiological variables during temperature variations at rest

    Science.gov (United States)

    Vogelaere, P.; de Meyer, F.

    1990-06-01

    The evolution with time of cardio-respiratory variables, blood pressure and body temperature has been studied on six males, resting in semi-nude conditions during short (30 min) cold stress exposure (0°C) and during passive recovery (60 min) at 20°C. Passive cold exposure does not induce a change in HR but increases VO 2, VCO 2 Ve and core temperature T re, whereas peripheral temperature is significantly lowered. The kinetic evolution of the studied variables was investigated using a Kelvin-Voigt rheological model. The results suggest that the human body, and by extension the measured physiological variables of its functioning, does not react as a perfect viscoelastic system. Cold exposure induces a more rapid adaptation for heart rate, blood pressure and skin temperatures than that observed during the rewarming period (20°C), whereas respiratory adjustments show an opposite evolution. During the cooling period of the experiment the adaptative mechanisms, taking effect to preserve core homeothermy and to obtain a higher oxygen supply, increase the energy loss of the body.

  20. The Amsterdam Resting-State Questionnaire reveals multiple phenotypes of resting-state cognition.

    Science.gov (United States)

    Diaz, B Alexander; Van Der Sluis, Sophie; Moens, Sarah; Benjamins, Jeroen S; Migliorati, Filippo; Stoffers, Diederick; Den Braber, Anouk; Poil, Simon-Shlomo; Hardstone, Richard; Van't Ent, Dennis; Boomsma, Dorret I; De Geus, Eco; Mansvelder, Huibert D; Van Someren, Eus J W; Linkenkaer-Hansen, Klaus

    2013-01-01

    Resting-state neuroimaging is a dominant paradigm for studying brain function in health and disease. It is attractive for clinical research because of its simplicity for patients, straightforward standardization, and sensitivity to brain disorders. Importantly, non-sensory experiences like mind wandering may arise from ongoing brain activity. However, little is known about the link between ongoing brain activity and cognition, as phenotypes of resting-state cognition-and tools to quantify them-have been lacking. To facilitate rapid and structured measurements of resting-state cognition we developed a 50-item self-report survey, the Amsterdam Resting-State Questionnaire (ARSQ). Based on ARSQ data from 813 participants assessed after 5 min eyes-closed rest in their home, we identified seven dimensions of resting-state cognition using factor analysis: Discontinuity of Mind, Theory of Mind, Self, Planning, Sleepiness, Comfort, and Somatic Awareness. Further, we showed that the structure of cognition was similar during resting-state fMRI and EEG, and that the test-retest correlations were remarkably high for all dimensions. To explore whether inter-individual variation of resting-state cognition is related to health status, we correlated ARSQ-derived factor scores with psychometric scales measuring depression, anxiety, and sleep quality. Mental health correlated positively with Comfort and negatively with Discontinuity of Mind. Finally, we show that sleepiness may partially explain a resting-state EEG profile previously associated with Alzheimer's disease. These findings indicate that the ARSQ readily provides information about cognitive phenotypes and that it is a promising tool for research on the neural correlates of resting-state cognition in health and disease.

  1. The Amsterdam Resting-State Questionnaire reveals multiple phenotypes of resting-state cognition

    Directory of Open Access Journals (Sweden)

    B. Alexander eDiaz

    2013-08-01

    Full Text Available Resting-state neuroimaging is a dominant paradigm for studying brain function in health and disease. It is attractive for clinical research because of its simplicity for patients, straightforward standardization, and sensitivity to brain disorders. Importantly, non-sensory experiences like mind wandering may arise from ongoing brain activity. However, little is known about the link between ongoing brain activity and cognition, as phenotypes of resting-state cognition—and tools to quantify them—have been lacking. To facilitate rapid and structured measurements of resting-state cognition we developed a 50-item self-report survey, the Amsterdam Resting-State Questionnaire (ARSQ. Based on ARSQ data from 813 participants assessed after five minutes eyes-closed rest in their home, we identified seven dimensions of resting-state cognition using factor analysis: Discontinuity of Mind, Theory of Mind, Self, Planning, Sleepiness, Comfort, and Somatic Awareness. Further, we showed that the structure of cognition was similar during resting-state fMRI and EEG, and that the test-retest correlations were remarkably high for all dimensions. To explore whether inter-individual variation of resting-state cognition is related to health status, we correlated ARSQ-derived factor scores with psychometric scales measuring depression, anxiety, and sleep quality. Mental health correlated positively with Comfort and negatively with Discontinuity of Mind. Finally, we show that sleepiness may partially explain a resting-state EEG profile previously associated with Alzheimer’s disease. These findings indicate that the ARSQ readily provides information about cognitive phenotypes and that it is a promising tool for research on the neural correlates of resting-state cognition in health and disease.

  2. Pre-measurement rest time affects magnitude and reliability of toe pressure measurements.

    Science.gov (United States)

    Chuter, Vivienne Helaine; Casey, Sarah Louise

    2015-06-01

    Toe pressures are used to evaluate lower extremity healing capacity and screen for peripheral arterial disease (PAD). Although toe pressures are commonly used clinically both as an independent measure and in the calculation of the toe-brachial index, the effect of pre-measurement rest duration on the magnitude and reliability of toe pressures is unknown. This study investigated the effect of pre-measurement rest duration on toe pressures. Seventy community-based participants meeting guidelines for PAD screening were recruited. Systolic toe pressures either at the left or right hallux were manually measured using photoplethysmography following 5, 10 and 15 min of rest in a supine horizontal position. Testing was repeated 7-10 days later. A significant drop in toe pressure (3.86 mmHg) occurred between 5 and 10 min (p = 0.001). No significant change occurred between 10 and 15 min. Reliability after 5 min was excellent (intra-class correlation coefficient, ICC = 0.80, 95% CI 0.68-0.89), increasing slightly at 10 and 15 min (ICC = 0.86, 95% CI 0.77-0.92 and ICC = 0.82, 95% CI 0.69-0.89). Toe pressures stabilize after 10 min of rest in a supine horizontal position. Longer periods of pre-measurement rest did not improve reliability significantly.

  3. Quasar Variability Measurements With SDSS Repeated Imaging and POSS Data

    CERN Document Server

    Ivezic, Z; Juric, M; Anderson, S; Hall, P B; Richards, G T; Rockosi, C M; Vanden Berk, Daniel E; Turner, E L; Knapp, G R; Gunn, J E; Schlegel, D J; Strauss, M A; Schneider, D P

    2004-01-01

    We analyze the properties of quasar variability using repeated SDSS imaging data in five UV-to-far red photometric bands, accurate to 0.02 mag, for 13,000 spectroscopically confirmed quasars. The observed time lags span the range from 3 hours to over 3 years, and constrain the quasar variability for rest-frame time lags of up to two years, and at rest-frame wavelengths from 1000 Ang. to 6000 Ang. We demonstrate that 66,000 SDSS measurements of magnitude differences can be described within the measurement noise by a simple function of only three free parameters. The addition of POSS data constrains the long-term behavior of quasar variability and provides evidence for a turn-over in the structure function. This turn-over indicates that the characteristic time scale for optical variability of quasars is of the order 1 year.

  4. Dual-Modality Input in Repeated Reading for Foreign Language Learners with Different Learning Styles

    Science.gov (United States)

    Liu, Yeu-Ting; Todd, Andrew Graeme

    2014-01-01

    Research into dual-modality theory has long rested on the assumption that presenting input in two modalities leads to better learning outcomes. However, this may not always hold true. This study explored the possible advantages of using dual modality in repeated reading--a pedagogy often used to enhance reading development--for two literacy…

  5. Dual-Modality Input in Repeated Reading for Foreign Language Learners with Different Learning Styles

    Science.gov (United States)

    Liu, Yeu-Ting; Todd, Andrew Graeme

    2014-01-01

    Research into dual-modality theory has long rested on the assumption that presenting input in two modalities leads to better learning outcomes. However, this may not always hold true. This study explored the possible advantages of using dual modality in repeated reading--a pedagogy often used to enhance reading development--for two literacy…

  6. Resting EEG asymmetry and spider phobia

    NARCIS (Netherlands)

    Merckelbach, H; Muris, P; Pool, K; de Jong, Peter

    1998-01-01

    This study examined whether resting EEG asymmetries are related to symptom severity and treatment outcome in spider phobia. Prior to treatment, EEG was recorded in a sample of spider phobic patients (N = 16). Correlations between frontal and parietal asymmetries in alpha power, on the one hand, and

  7. Wakeful rest alleviates interference-based forgetting.

    Science.gov (United States)

    Mercer, Tom

    2015-01-01

    Retroactive interference (RI)--the disruptive influence of events occurring after the formation of a new memory--is one of the primary causes of forgetting. Placing individuals within an environment that postpones interference should, therefore, greatly reduce the likelihood of information being lost from memory. For example, a short period of wakeful rest should diminish interference-based forgetting. To test this hypothesis, participants took part in a foreign language learning activity and were shown English translations of 20 Icelandic words for immediate recall. Half of the participants were then given an 8-min rest before completing a similar or dissimilar interfering distractor task. The other half did not receive a rest until after the distractor task, at which point interference had already taken place. All participants were then asked to translate the Icelandic words for a second time. Results revealed that retention was significantly worse at the second recall test, but being allowed a brief rest before completing the distractor task helped reduce the amount of forgetting. Taking a short, passive break can shield new memories from RI and alleviate forgetting.

  8. Positive pressure breathing during rest and exercise

    NARCIS (Netherlands)

    Hartog, E.A. den; Heus, R.

    2003-01-01

    The requirements to maintain a positive pressure with respiratory protection during heavy exercise and the effects on ventilation and feelings of discomfort were investigated. Eight male subjects participated, using the respirator system during rest and exercise at about 80% of their individual

  9. 1 SHORT COMMUNICATION Resting behaviour of Anopheles ...

    African Journals Online (AJOL)

    2011-10-04

    Oct 4, 2011 ... resting and feeding behaviour, adult longevity and density as they determine the degree of .... Table 1: Number and density of An.gambiae per room collected using mechanical aspirator and exit trap ... This is the first report on.

  10. Positive pressure breathing during rest and exercise

    NARCIS (Netherlands)

    Hartog, E.A. den; Heus, R.

    2003-01-01

    The requirements to maintain a positive pressure with respiratory protection during heavy exercise and the effects on ventilation and feelings of discomfort were investigated. Eight male subjects participated, using the respirator system during rest and exercise at about 80% of their individual maxi

  11. Exercise Training During Bed Rest Attenuates Deconditioning

    Science.gov (United States)

    Greenleaf, J. E.; Hargens, Alan R. (Technical Monitor)

    1995-01-01

    A 30-day 6 deg. head-down bed rest study was conducted to evaluate high-intensity, short-duration, alternating isotonic cycle ergometer exercise (ITE) training and high-intensity intermittent isokinetic exercise (IKE) training regiments designed to maintain peak VO2 and muscle mass, strength, and endurance at ambulatory control levels throughout prolonged bed rest. Other elements of the deconditioning (acclimation) syndrome, such as proprioception, psychological performance, hypovolemia, water balance, body composition, and orthostatic tolerance, were also measured. Compared with response during bed rest of the no exercise (NOE) control group: the ITE training regimen (a) maintained work capacity (peak VO2), (b) maintained plasma and red cell volume, (c) induced positive body water balance, (d) decreased quality of sleep and mental concentration, and (e) had no effect on the decrease in orthostatic tolerance; the IKE training regimen (a) attenuated the decrease in peak VO2 by 50%, (b) attenuated loss of red cell volume by 40%, but had no effect on loss of plasma volume, (c) induced positive body water balance, (d) had no adverse effect on quality of sleep or concentration, and (e) had no effect on the decrease in orthostatic tolerance. These findings suggest that various elements of the deconditioning syndrome can be manipulated by duration and intensity of ITE or IKE training regiments, and that several different training protocols will be required to maintain or restore physiological and psychological performance of individuals confined to prolonged bed rest.

  12. 46 CFR 15.1111 - Work hours and rest periods.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Work hours and rest periods. 15.1111 Section 15.1111... REQUIREMENTS Vessels Subject to Requirements of STCW § 15.1111 Work hours and rest periods. (a) Each person... shall receive a minimum of 10 hours of rest in any 24-hour period. (b) The hours of rest required under...

  13. 23 CFR 752.5 - Safety rest areas.

    Science.gov (United States)

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false Safety rest areas. 752.5 Section 752.5 Highways FEDERAL... DEVELOPMENT § 752.5 Safety rest areas. (a) Safety rest areas should provide facilities reasonably necessary... may be provided in conjunction with a safety rest area at such locations where accommodations...

  14. Cardiac atrophy after bed rest and spaceflight

    Science.gov (United States)

    Perhonen, M. A.; Franco, F.; Lane, L. D.; Buckey, J. C.; Blomqvist, C. G.; Zerwekh, J. E.; Peshock, R. M.; Weatherall, P. T.; Levine, B. D.

    2001-01-01

    Cardiac muscle adapts well to changes in loading conditions. For example, left ventricular (LV) hypertrophy may be induced physiologically (via exercise training) or pathologically (via hypertension or valvular heart disease). If hypertension is treated, LV hypertrophy regresses, suggesting a sensitivity to LV work. However, whether physical inactivity in nonathletic populations causes adaptive changes in LV mass or even frank atrophy is not clear. We exposed previously sedentary men to 6 (n = 5) and 12 (n = 3) wk of horizontal bed rest. LV and right ventricular (RV) mass and end-diastolic volume were measured using cine magnetic resonance imaging (MRI) at 2, 6, and 12 wk of bed rest; five healthy men were also studied before and after at least 6 wk of routine daily activities as controls. In addition, four astronauts were exposed to the complete elimination of hydrostatic gradients during a spaceflight of 10 days. During bed rest, LV mass decreased by 8.0 +/- 2.2% (P = 0.005) after 6 wk with an additional atrophy of 7.6 +/- 2.3% in the subjects who remained in bed for 12 wk; there was no change in LV mass for the control subjects (153.0 +/- 12.2 vs. 153.4 +/- 12.1 g, P = 0.81). Mean wall thickness decreased (4 +/- 2.5%, P = 0.01) after 6 wk of bed rest associated with the decrease in LV mass, suggesting a physiological remodeling with respect to altered load. LV end-diastolic volume decreased by 14 +/- 1.7% (P = 0.002) after 2 wk of bed rest and changed minimally thereafter. After 6 wk of bed rest, RV free wall mass decreased by 10 +/- 2.7% (P = 0.06) and RV end-diastolic volume by 16 +/- 7.9% (P = 0.06). After spaceflight, LV mass decreased by 12 +/- 6.9% (P = 0.07). In conclusion, cardiac atrophy occurs during prolonged (6 wk) horizontal bed rest and may also occur after short-term spaceflight. We suggest that cardiac atrophy is due to a physiological adaptation to reduced myocardial load and work in real or simulated microgravity and demonstrates the plasticity

  15. Cardiac atrophy after bed rest and spaceflight

    Science.gov (United States)

    Perhonen, M. A.; Franco, F.; Lane, L. D.; Buckey, J. C.; Blomqvist, C. G.; Zerwekh, J. E.; Peshock, R. M.; Weatherall, P. T.; Levine, B. D.

    2001-01-01

    Cardiac muscle adapts well to changes in loading conditions. For example, left ventricular (LV) hypertrophy may be induced physiologically (via exercise training) or pathologically (via hypertension or valvular heart disease). If hypertension is treated, LV hypertrophy regresses, suggesting a sensitivity to LV work. However, whether physical inactivity in nonathletic populations causes adaptive changes in LV mass or even frank atrophy is not clear. We exposed previously sedentary men to 6 (n = 5) and 12 (n = 3) wk of horizontal bed rest. LV and right ventricular (RV) mass and end-diastolic volume were measured using cine magnetic resonance imaging (MRI) at 2, 6, and 12 wk of bed rest; five healthy men were also studied before and after at least 6 wk of routine daily activities as controls. In addition, four astronauts were exposed to the complete elimination of hydrostatic gradients during a spaceflight of 10 days. During bed rest, LV mass decreased by 8.0 +/- 2.2% (P = 0.005) after 6 wk with an additional atrophy of 7.6 +/- 2.3% in the subjects who remained in bed for 12 wk; there was no change in LV mass for the control subjects (153.0 +/- 12.2 vs. 153.4 +/- 12.1 g, P = 0.81). Mean wall thickness decreased (4 +/- 2.5%, P = 0.01) after 6 wk of bed rest associated with the decrease in LV mass, suggesting a physiological remodeling with respect to altered load. LV end-diastolic volume decreased by 14 +/- 1.7% (P = 0.002) after 2 wk of bed rest and changed minimally thereafter. After 6 wk of bed rest, RV free wall mass decreased by 10 +/- 2.7% (P = 0.06) and RV end-diastolic volume by 16 +/- 7.9% (P = 0.06). After spaceflight, LV mass decreased by 12 +/- 6.9% (P = 0.07). In conclusion, cardiac atrophy occurs during prolonged (6 wk) horizontal bed rest and may also occur after short-term spaceflight. We suggest that cardiac atrophy is due to a physiological adaptation to reduced myocardial load and work in real or simulated microgravity and demonstrates the plasticity

  16. REST: a toolkit for resting-state functional magnetic resonance imaging data processing.

    Science.gov (United States)

    Song, Xiao-Wei; Dong, Zhang-Ye; Long, Xiang-Yu; Li, Su-Fang; Zuo, Xi-Nian; Zhu, Chao-Zhe; He, Yong; Yan, Chao-Gan; Zang, Yu-Feng

    2011-01-01

    Resting-state fMRI (RS-fMRI) has been drawing more and more attention in recent years. However, a publicly available, systematically integrated and easy-to-use tool for RS-fMRI data processing is still lacking. We developed a toolkit for the analysis of RS-fMRI data, namely the RESting-state fMRI data analysis Toolkit (REST). REST was developed in MATLAB with graphical user interface (GUI). After data preprocessing with SPM or AFNI, a few analytic methods can be performed in REST, including functional connectivity analysis based on linear correlation, regional homogeneity, amplitude of low frequency fluctuation (ALFF), and fractional ALFF. A few additional functions were implemented in REST, including a DICOM sorter, linear trend removal, bandpass filtering, time course extraction, regression of covariates, image calculator, statistical analysis, and slice viewer (for result visualization, multiple comparison correction, etc.). REST is an open-source package and is freely available at http://www.restfmri.net.

  17. Smart: Semantically Mashup Rest Web Services

    Directory of Open Access Journals (Sweden)

    Rima Kilany

    2013-10-01

    Full Text Available A mashup is a combination of information from more than one source, mixed up in a way to create something new, or at least useful. Anyone can find mashups on the internet, but these are always specifically designed for a predefined purpose. To change that fact, we implemented a new platform we called the SMART platform. SMART enables the user to make his own choices as for the REST web services he needs to call in order to build an intelligent personalized mashup, from a Google-like simple search interface, without needing any programming skills. In order to achieve this goal, we defined an ontology that can hold REST web services descriptions. These descriptions encapsulate mainly, the input type needed for a service, its output type, and the kind of relation that ties the input to the output. Then, by matching the user input query keywords, with the REST web services definitions in our ontology, we can find registered services individuals in this ontology, and construct the raw REST query for each service found. The wrap up from the keywords, into semantic definitions, in order to find the matching service individual, then the wrap down from the semantic service description of the found individual, to the raw REST call, and finally the wrap up of the result again into semantic individuals, is done for two main purposes: the first to let the user use simple keywords in order to build complex mashups, and the second to benefit from the ontology’s inference engine in a way, where services instances can be tied together into an intelligent mashup, simply by making each service output individuals, stand as the next service input.

  18. Solar energy estimation using REST2 model

    Directory of Open Access Journals (Sweden)

    M. Rizwan, Majid Jamil, D. P. Kothari

    2010-03-01

    Full Text Available The network of solar energy measuring stations is relatively rare through out the world. In India, only IMD (India Meteorological Department Pune provides data for quite few stations, which is considered as the base data for research purposes. However, hourly data of measured energy is not available, even for those stations where measurement has already been done. Due to lack of hourly measured data, the estimation of solar energy at the earth’s surface is required. In the proposed study, hourly solar energy is estimated at four important Indian stations namely New Delhi, Mumbai, Pune and Jaipur keeping in mind their different climatic conditions. For this study, REST2 (Reference Evaluation of Solar Transmittance, 2 bands, a high performance parametric model for the estimation of solar energy is used. REST2 derivation uses the two-band scheme as used in the CPCR2 (Code for Physical Computation of Radiation, 2 bands but CPCR2 does not include NO2 absorption, which is an important parameter for estimating solar energy. In this study, using ground measurements during 1986-2000 as reference, a MATLAB program is written to evaluate the performance of REST2 model at four proposed stations. The solar energy at four stations throughout the year is estimated and compared with CPCR2. The results obtained from REST2 model show the good agreement against the measured data on horizontal surface. The study reveals that REST2 models performs better and evaluate the best results as compared to the other existing models under cloudless sky for Indian climatic conditions.

  19. Analysis of repeated measures data

    CERN Document Server

    Islam, M Ataharul

    2017-01-01

    This book presents a broad range of statistical techniques to address emerging needs in the field of repeated measures. It also provides a comprehensive overview of extensions of generalized linear models for the bivariate exponential family of distributions, which represent a new development in analysing repeated measures data. The demand for statistical models for correlated outcomes has grown rapidly recently, mainly due to presence of two types of underlying associations: associations between outcomes, and associations between explanatory variables and outcomes. The book systematically addresses key problems arising in the modelling of repeated measures data, bearing in mind those factors that play a major role in estimating the underlying relationships between covariates and outcome variables for correlated outcome data. In addition, it presents new approaches to addressing current challenges in the field of repeated measures and models based on conditional and joint probabilities. Markov models of first...

  20. The impact of stimulus valence and emotion regulation on sustained brain activation: task-rest switching in emotion.

    Science.gov (United States)

    Lamke, Jan-Peter; Daniels, Judith K; Dörfel, Denise; Gaebler, Michael; Abdel Rahman, Rasha; Hummel, Falk; Erk, Susanne; Walter, Henrik

    2014-01-01

    Task-rest interactions, defined as the modulation of brain activation during fixation periods depending on the preceding stimulation and experimental manipulation, have been described repeatedly for different cognitively demanding tasks in various regions across the brain. However, task-rest interactions in emotive paradigms have received considerably less attention. In this study, we therefore investigated task-rest interactions evoked by the induction and instructed regulation of negative emotion. Whole-brain, functional MRI data were acquired from 55 healthy participants. Two-level general linear model statistics were computed to test for differences between conditions, separately for stimulation and for fixation periods, as well as for interactions between stimulation and fixation (task-rest interactions). Results showed that the regulation of negative emotion led to reverse task-rest interactions (decreased activation during stimulation but increased activation during fixation) in the amygdala as well as in visual cortex regions and to concordant task-rest interactions (increased activation during both, stimulation and fixation) in the dorsolateral prefrontal cortex as well as in a number of brain regions at the intersection of the default mode and the dorsal attention networks. Thus, this first whole-brain investigation of task-rest interactions following the induction and regulation of negative emotion identified a widespread specific modulation of brain activation in regions subserving emotion generation and regulation as well as regions implicated in attention and default mode.

  1. Exercise Thermoregulation Following 13 Days of Bed Rest

    Science.gov (United States)

    Lee, Stuart M. C.; Williams, W. Jon; Schneider, Suzanne M.

    2001-01-01

    .06 +/- 0.1 1 vs. 37.34 +/- 0.06 C; p less than or equal to 0.05). However, the slope of SR was not changed after BR (3.45 +/- 1.22 vs. 2.58 +/- 0.71 mg multiplied by min(exp -1) multiplied by cm sq). PV was decreased by 11% after BR (3,259 +/- 177 vs. 2,894 +/- 138 ml; p less than or equal to 0.05). These results suggest that exercise SBF and SR responses after BR are altered, and heat production is unchanged or reduced, consistent with observations following space flight. The higher resting T(sub in) with a proportional increase in T(sub in) during exercise and delayed onset of SBF and SR suggest a centrally-mediated elevation in the thermoregulatory set point during microgravity exposure.

  2. 解析Restful Web Service架构%Analysis of Restful Web Service Architecture

    Institute of Scientific and Technical Information of China (English)

    赵博文

    2008-01-01

    本文展示了Http协议的强大能力,如何定义什么是Restful Web Service架构以及以当今RPC式Web服务的对比,并解析了Restful Web Service架构的四个特征:可寻址性、无状态性、连通性和统一接口.

  3. "Let It Rest:" Reflecting on Instructional Practice

    Science.gov (United States)

    Fontichiaro, Kristin

    2011-01-01

    Top Chef is one of America's top food television shows. In one episode, lead judge Tom Colicchio, chef and restaurant owner, chides a contestant for hurriedly slicing a piece of meat as soon as it had emerged from the oven. The meat was fully cooked, but the competitor had not "let it rest," or let it steep in its own juices outside the oven for…

  4. "Let It Rest:" Reflecting on Instructional Practice

    Science.gov (United States)

    Fontichiaro, Kristin

    2011-01-01

    Top Chef is one of America's top food television shows. In one episode, lead judge Tom Colicchio, chef and restaurant owner, chides a contestant for hurriedly slicing a piece of meat as soon as it had emerged from the oven. The meat was fully cooked, but the competitor had not "let it rest," or let it steep in its own juices outside the oven for…

  5. If I Rest,I Rust

    Institute of Scientific and Technical Information of China (English)

    Orison; Swett; Marden; 陆小丫

    2003-01-01

    选注者言:流水不腐,户枢不蠹。人的才干又何尝不是如此?If I Rest,I Rust 的标题就让我们玩味再三!思之再三,权译:吾“休”则“锈”。宝剑锋从磨砺出, 梅花香自苦寒来。此言非虚!

  6. Exposure Forecaster

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Exposure Forecaster Database (ExpoCastDB) is EPA's database for aggregating chemical exposure information and can be used to help with chemical exposure...

  7. Methyldibromoglutaronitrile allergy: relationship between patch test and repeated open application test thresholds

    DEFF Research Database (Denmark)

    Fischer, L.A.; Johansen, J.D.; Menne, T.

    2008-01-01

    a significant relationship between the patch test and the repeated open application test (ROAT) reactivity. Objectives To study the relationship between elicitation threshold doses at single occluded exposure and repeated open application, using MDBGN as the allergen. Methods Eighteen subjects allergic to MDBGN...

  8. Nuclear capture at rest of Ξ hyperons

    Science.gov (United States)

    Aoki, S.; Bahk, S. Y.; Chung, S. H.; Funahashi, H.; Hahn, C. H.; Hanabata, M.; Hara, T.; Hirata, S.; Hoshino, K.; Ieiri, M.; Iijima, T.; Imai, K.; Itow, Y.; Jin-ya, T.; Kazuno, M.; Kim, C. O.; Kim, J. Y.; Kim, S. H.; Kodama, K.; Kuze, T.; Maeda, Y.; Masaike, A.; Masuoka, A.; Matsuda, Y.; Matsui, A.; Nagase, Y.; Nagoshi, C.; Nakamura, M.; Nakanishi, S.; Nakano, T.; Nakazawa, K.; Niwa, K.; Oda, H.; Okabe, H.; Ono, S.; Ozaki, R.; Park, B. D.; Park, I. G.; Sakai, K.; Sasaki, T.; Sato, Y.; Shibuya, H.; Shimizu, H. M.; Song, J. S.; Sugimoto, M.; Tajima, H.; Takahashi, H.; Takashima, R.; Takeutchi, F.; Tanaka, K. H.; Teranaka, M.; Tezuka, I.; Togawa, H.; Tsunemi, T.; Ukai, M.; Ushida, N.; Watanabe, T.; Yasuda, N.; Yokota, J.; Yoon, C. S.; KEK E176 Collaboration

    2009-09-01

    An emulsion-counter hybrid experiment (KEK E176) was carried out to search for double strangeness systems such as double- Λ hypernuclei and H-dibaryons. More than 10% of Ξ hyperons produced in the (K -, K +) reaction were brought to rest in the nuclear emulsion. We have obtained 98 candidate events of nuclear capture at rest of Ξ hyperons which are described in this report. Among those, four events were identified as sequential weak decay of double- Λ hypernuclei. The binding energies of Ξ-( 12C, 14N and 16O) states have been estimated for two events which emit twin single- Λ hypernuclei back to back from the capture point. The Σp decay vertex of an H-dibaryon was searched for near the capture point and no evidence was observed. Upper limits for the branching ratio of H emission are 5-10% for a lifetime less than 0.1 ns at the 90% confidence level. The trapping probabilities of single and double strangeness to a nuclear fragment following Ξ capture at rest have been studied.

  9. Watching the fetal brain at 'rest'.

    Science.gov (United States)

    Schöpf, V; Kasprian, G; Brugger, P C; Prayer, D

    2012-02-01

    Functional magnetic resonance imaging (fMRI) has allowed insights into the spatiotemporal distribution of human brain networks. According to the neurophysiological property of the fetal brain to generate spontaneous activity, we aimed to determine the feasibility of investigating the maturation of intrinsic networks, beginning at gestational week 20 in healthy human fetuses by combining resting-state fMRI and an analytical approach, independent component analysis (ICA). In this study, functional images of 16 fetuses with morphologically normal brain development, from 20 to 36 gestational weeks of age, were acquired on a 1.5T unit (Philips Medical Systems, Best, The Netherlands) using single-shot, gradient-recalled echo-planar imaging. After preprocessing (motion correction, brain extraction), images were analyzed using single-subject ICA. We visualized a bilateral occipital network and medial and lateral prefrontal activity pattern that involved the future Brodmann areas 9-11. Furthermore, there was one either predominantly right (3/7 cases) or left (4/7 cases) hemispheric lateralized network that involved the superior temporal cortical regions (Brodmann areas 22 and 39). Frequency oscillations were in the range of 0.01-0.06Hz for all networks. This study shows that resting-state networks (RSNs) are shaped and are detectable in utero. Further investigations of resting-state measurements in the fetus may therefore allow developmental brain activity monitoring and may provide insights into early brain function. Copyright © 2011 ISDN. Published by Elsevier Ltd. All rights reserved.

  10. The potential of iRest in measuring the hand function performance of stroke patients.

    Science.gov (United States)

    Abdul Rahman, Hisyam; Khor, Kang Xiang; Yeong, Che Fai; Su, Eileen Lee Ming; Narayanan, Aqilah Leela T

    2017-01-01

    Clinical scales such as Fugl-Meyer Assessment (FMA) and Motor Assessment Scale (MAS) are widely used to evaluate stroke patient's motor performance. However, there are several limitations with these assessment scales such as subjectivity, lack of repeatability, time-consuming and highly depend on the ability of the physiotherapy. In contrast, robot-based assessments are objective, repeatable, and could potentially reduce the assessment time. However, robot-based assessments are not as well established as conventional assessment scale and the correlation to conventional assessment scale is unclear. This study was carried out to identify important parameters in designing tasks that efficiently assess hand function of stroke patients and to quantify potential benefits of robotic assessment modules to predict the conventional assessment score with iRest. Twelve predictive variables were explored, relating to movement time, velocity, strategy, accuracy and smoothness from three robotic assessment modules which are Draw I, Draw Diamond and Draw Circle. Regression models using up to four predictors were developed to describe the MAS. Results show that the time given should be not too long and it would affect the trajectory error. Besides, result also shows that it is possible to use iRest in predicting MAS score. There is a potential of using iRest, a non-motorized device in predicting MAS score.

  11. Limitations on quantum key repeaters.

    Science.gov (United States)

    Bäuml, Stefan; Christandl, Matthias; Horodecki, Karol; Winter, Andreas

    2015-04-23

    A major application of quantum communication is the distribution of entangled particles for use in quantum key distribution. Owing to noise in the communication line, quantum key distribution is, in practice, limited to a distance of a few hundred kilometres, and can only be extended to longer distances by use of a quantum repeater, a device that performs entanglement distillation and quantum teleportation. The existence of noisy entangled states that are undistillable but nevertheless useful for quantum key distribution raises the question of the feasibility of a quantum key repeater, which would work beyond the limits of entanglement distillation, hence possibly tolerating higher noise levels than existing protocols. Here we exhibit fundamental limits on such a device in the form of bounds on the rate at which it may extract secure key. As a consequence, we give examples of states suitable for quantum key distribution but unsuitable for the most general quantum key repeater protocol.

  12. Effects of 60-day bed rest with and without exercise on cellular and humoral immunological parameters.

    Science.gov (United States)

    Hoff, Paula; Belavý, Daniel L; Huscher, Dörte; Lang, Annemarie; Hahne, Martin; Kuhlmey, Anne-Kathrin; Maschmeyer, Patrick; Armbrecht, Gabriele; Fitzner, Rudolf; Perschel, Frank H; Gaber, Timo; Burmester, Gerd-Rüdiger; Straub, Rainer H; Felsenberg, Dieter; Buttgereit, Frank

    2015-07-01

    Exercise at regular intervals is assumed to have a positive effect on immune functions. Conversely, after spaceflight and under simulated weightlessness (e.g., bed rest), immune functions can be suppressed. We aimed to assess the effects of simulated weightlessness (Second Berlin BedRest Study; BBR2-2) on immunological parameters and to investigate the effect of exercise (resistive exercise with and without vibration) on these changes. Twenty-four physically and mentally healthy male volunteers (20-45 years) performed resistive vibration exercise (n=7), resistance exercise without vibration (n=8) or no exercise (n=9) within 60 days of bed rest. Blood samples were taken 2 days before bed rest, on days 19 and 60 of bed rest. Composition of immune cells was analyzed by flow cytometry. Cytokines and neuroendocrine parameters were analyzed by Luminex technology and ELISA/RIA in plasma. General changes over time were identified by paired t-test, and exercise-dependent effects by pairwise repeated measurements (analysis of variance (ANOVA)). With all subjects pooled, the number of granulocytes, natural killer T cells, hematopoietic stem cells and CD45RA and CD25 co-expressing T cells increased and the number of monocytes decreased significantly during the study; the concentration of eotaxin decreased significantly. Different impacts of exercise were seen for lymphocytes, B cells, especially the IgD(+) subpopulation of B cells and the concentrations of IP-10, RANTES and DHEA-S. We conclude that prolonged bed rest significantly impacts immune cell populations and cytokine concentrations. Exercise was able to specifically influence different immunological parameters. In summary, our data fit the hypothesis of immunoprotection by exercise and may point toward even superior effects by resistive vibration exercise.

  13. Spatially distributed effects of mental exhaustion on resting-state FMRI networks.

    Directory of Open Access Journals (Sweden)

    Fabrizio Esposito

    Full Text Available Brain activity during rest is spatially coherent over functional connectivity networks called resting-state networks. In resting-state functional magnetic resonance imaging, independent component analysis yields spatially distributed network representations reflecting distinct mental processes, such as intrinsic (default or extrinsic (executive attention, and sensory inhibition or excitation. These aspects can be related to different treatments or subjective experiences. Among these, exhaustion is a common psychological state induced by prolonged mental performance. Using repeated functional magnetic resonance imaging sessions and spatial independent component analysis, we explored the effect of several hours of sustained cognitive performances on the resting human brain. Resting-state functional magnetic resonance imaging was performed on the same healthy volunteers in two days, with and without, and before, during and after, an intensive psychological treatment (skill training and sustained practice with a flight simulator. After each scan, subjects rated their level of exhaustion and performed an N-back task to evaluate eventual decrease in cognitive performance. Spatial maps of selected resting-state network components were statistically evaluated across time points to detect possible changes induced by the sustained mental performance. The intensive treatment had a significant effect on exhaustion and effort ratings, but no effects on N-back performances. Significant changes in the most exhausted state were observed in the early visual processing and the anterior default mode networks (enhancement and in the fronto-parietal executive networks (suppression, suggesting that mental exhaustion is associated with a more idling brain state and that internal attention processes are facilitated to the detriment of more extrinsic processes. The described application may inspire future indicators of the level of fatigue in the neural attention system.

  14. Can different conditioning activities and rest intervals affect the acute performance of taekwondo turning kick?

    Science.gov (United States)

    Santos, Jonatas F da Silva; Valenzuela, Tomás H; Franchini, Emerson

    2015-06-01

    This study compared the acute effect of strength, plyometric, and complex exercises (combined strength and plyometric exercise) in the countermovement jump (CMJ) and frequency speed of kick test (FSKT) and attempted to establish the best rest interval to maximize performance in the CMJ, number of kicks, and impact generated during FSKT. Eleven taekwondo athletes (mean ± SD; age: 20.3 ± 5.2 years; body mass: 71.8 ± 15.3 kg; height: 177 ± 7.2 cm) participated. One control and 9 experimental conditions were randomly applied. Each condition was composed of warm-up, conditioning activity (half-squat: 3 × 1 at 95% 1RM; jumps: 3 × 10 vertical jumps above 40-cm barrier; or complex exercise: half-squat 3 × 2 at 95% 1RM + 4 vertical jumps above 40-cm barrier), followed by different rest intervals (5-, 10-minute, and self-selected) before CMJ and FSKT. The conditions were compared using an analysis of variance with repeated measures, followed by Bonferroni's post hoc test. The alpha level was set at 5%. Significant difference was found in the number of kicks (F9,90 = 1.32; p = 0.239; and η2 = 0.116 [small]). The complex method with a 10-minute rest interval (23 ± 5 repetitions) was superior (p = 0.026) to the control (19 ± 3 repetitions), maximum strength with a self-selected rest interval (328 ± 139 seconds; 18 ± 2 repetitions) (p = 0.015), and plyometric with a 5-minute rest interval (18 ± 3 repetitions) (p taekwondo athletes increased the number of kicks in a specific test by using the complex method when 10-minute rest interval was used.

  15. Sleep and alertness during alternating monophasic and polyphasic rest-activity cycles.

    Science.gov (United States)

    Porcú, S; Casagrande, M; Ferrara, M; Bellatreccia, A

    1998-07-01

    People involved in shift work often have to face altered patterns of sleep and wakefulness. This is particularly true for schedules involving night shifts and/or fragmentation of duty periods throughout the 24-hr day. In such conditions, it can be difficult to obtain satisfactory periods of sleep, and sleepiness on duty is a frequent and dangerous occurrence. The aim of this study was to evaluate sleep and wakefulness periods of subjects whose work schedule was characterized by an alternation of 2 hours of activity and 4 hours of rest (sleep allowed), repeated 4 times throughout the 24-hr day. This schedule was alternated with 24 hours off duty. Nine healthy male volunteers were monitored by means of ambulatory polysomnography while attending their 24-hr rest-activity schedule. Sleep periods were visually scored according to standard criteria. Wake periods were visually scored using both 30 s and 5 s epochs in order to reveal episodes of drowsiness and/or microsleep. Results showed that total sleep time was substantially reduced as compared to the usual 7-8 hour monophasic nocturnal sleep. Subjects did not sleep during the first rest period (11.00-15.00). Time in sleep linearly increased in the course of the 3 remaining rest periods. Normal sleep stage distribution was substantially spared only in the last rest period (3.00-7.00 a.m.). With regard to duty periods, only a few microsleeps were detected and their number did not significantly vary across the four 2-hr activity periods. In conclusion, this rest-activity schedule, despite the considerable sleep reduction, allowed maintaining good levels of vigilance as shown by the virtual absence of EEG microsleeps. Whether future research will prove that this regimen does not cause an impairment of performance, it should be a suitable strategy for the management of continuous operations.

  16. Hysteresis of magnetostructural transitions: Repeatable and non-repeatable processes

    Energy Technology Data Exchange (ETDEWEB)

    Provenzano, Virgil [National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States); Della Torre, Edward; Bennett, Lawrence H. [Department of Electrical and Computer Engineering, The George Washington University, Washington, DC 20052 (United States); ElBidweihy, Hatem, E-mail: Hatem@gwmail.gwu.edu [Department of Electrical and Computer Engineering, The George Washington University, Washington, DC 20052 (United States)

    2014-02-15

    The Gd{sub 5}Ge{sub 2}Si{sub 2} alloy and the off-stoichiometric Ni{sub 50}Mn{sub 35}In{sub 15} Heusler alloy belong to a special class of metallic materials that exhibit first-order magnetostructural transitions near room temperature. The magnetic properties of this class of materials have been extensively studied due to their interesting magnetic behavior and their potential for a number of technological applications such as refrigerants for near-room-temperature magnetic refrigeration. The thermally driven first-order transitions in these materials can be field-induced in the reverse order by applying a strong enough field. The field-induced transitions are typically accompanied by the presence of large magnetic hysteresis, the characteristics of which are a complicated function of temperature, field, and magneto-thermal history. In this study we show that the virgin curve, the major loop, and sequentially measured MH loops are the results of both repeatable and non-repeatable processes, in which the starting magnetostructural state, prior to the cycling of field, plays a major role. Using the Gd{sub 5}Ge{sub 2}Si{sub 2} and Ni{sub 50}Mn{sub 35}In{sub 15} alloys, as model materials, we show that a starting single phase state results in fully repeatable processes and large magnetic hysteresis, whereas a mixed phase starting state results in non-repeatable processes and smaller hysteresis.

  17. Cardiovascular adjustments and pain during repeated cold pressor test.

    Science.gov (United States)

    Stancák, A; Yamamotová, A; Kulls, I P; Sekyra, I V

    1996-04-01

    The cold pressor test is used in the clinical testing of the autonomic nervous system. However, little is known about changes in the autonomic control of the cardiovascular system during repeated challenge with cold. Heart rate (HR), respiratory sinus arrhythmia (RSA), T-wave amplitude of ECG (TWA), blood pressure, body temperature and perceived pain were recorded in 18 male subjects during three CPTs which consisted of four minutes immersion of the left hand into cold water at 1 degree C. Breathing during CPT was either spontaneous or paced at 0.23 Hz or 0.1 Hz. Pain intensity and HR decreased and TWA increased during the cold immersion and in the resting period preceding cold in the second and third trials. Systolic and pulse blood pressure increased in resting periods in the third trial. RSA increased in the second and third cold challenge during paced breathing at 0.1 Hz only. A decrease in body temperature (0.48 degree C) at the end of the experiment correlated marginally with HR changes. Our study shows that sustained cardiovascular changes are induced by the first challenge with cold, and persist or increase with repeated cold pressor tests.

  18. Neuro-mechanical determinants of repeated treadmill sprints - Usefulness of an ‘hypoxic to normoxic recovery’ approach

    Directory of Open Access Journals (Sweden)

    Olivier eGIRARD

    2015-09-01

    Full Text Available To improve our understanding of the limiting factors during repeated sprinting, we manipulated hypoxia severity during an initial set and examined the effects on performance and associated neuro-mechanical alterations during a subsequent set performed in normoxia. On separate days, thirteen active males performed eight 5-s sprints (recovery = 25 s on an instrumented treadmill in either normoxia near sea-level (SL; FiO2 = 20.9%, moderate (MH; FiO2 = 16.8% or severe normobaric hypoxia (SH; FiO2 = 13.3% followed, 6 min later, by four 5-s sprints (recovery = 25 s in normoxia. Throughout the first set, along with distance covered [larger sprint decrement score in SH (-8.2% compared to SL (-5.3% and MH (-7.2%; P<0.05], changes in contact time, step frequency and root mean square activity (surface electromyography of the quadriceps (rectus femoris muscle in SH exceeded those in SL and MH (P<0.05. During first sprint of the subsequent normoxic set, the distance covered (99.6%, 96.4% and 98.3% of sprint 1 in SL, MH and SH, respectively, the main kinetic (mean, horizontal and resultant forces and kinematic (contact time and step frequency variables as well as surface electromyogram of quadriceps and plantar flexor muscles were fully recovered, with no significant difference between conditions. Despite differing hypoxic severity levels during sprints 1 to 8, performance and neuro-mechanical patterns did not differ during the four sprints of the second set performed in normoxia. In summary, under the circumstances of this study (participant background, exercise-to-rest ratio, hypoxia exposure, sprint mechanical performance and neural alterations were largerly influenced by the hypoxia severity in an initial set of repeated sprints. However, hypoxia had no residual effect during a subsequent set performed in normoxia. Hence, the recovery of performance and associated neuro-mechanical alterations was complete after resting for 6 min near sea level, with a

  19. The transcription factor REST is lost in aggressive breast cancer.

    Directory of Open Access Journals (Sweden)

    Matthew P Wagoner

    2010-06-01

    Full Text Available The function of the tumor suppressor RE1 silencing transcription factor (REST is lost in colon and small cell lung cancers and is known to induce anchorage-independent growth in human mammary epithelial cells. However, nothing is currently known about the role of this tumor suppressor in breast cancer. Here, we test the hypothesis that loss of REST function plays a role in breast cancer. To assay breast tumors for REST function, we developed a 24-gene signature composed of direct targets of the transcriptional repressor. Using the 24- gene signature, we identified a previously undefined RESTless breast tumor subtype. Using gene set enrichment analysis, we confirmed the aberrant expression of REST target genes in the REST-less tumors, including neuronal gene targets of REST that are normally not expressed outside the nervous system. Examination of REST mRNA identified a truncated splice variant of REST present in the REST-less tumor population, but not other tumors. Histological analysis of 182 outcome-associated breast tumor tissues also identified a subpopulation of tumors that lack full-length, functional REST and over-express the neuroendocrine marker and REST target gene Chromogranin A. Importantly, patients whose tumors were found to be REST-less using either the 24-gene signature or histology had significantly poorer prognosis and were more than twice as likely to undergo disease recurrence within the first 3 years after diagnosis. We show here that REST function is lost in breast cancer, at least in part via an alternative splicing mechanism. Patients with REST-less breast cancer undergo significantly more early disease recurrence than those with fully functional REST, regardless of estrogen receptor or HER2 status. Importantly, REST status may serve as a predictor of poor prognosis, helping to untangle the heterogeneity inherent in disease course and response to treatment. Additionally, the alternative splicing observed in REST

  20. What is the best?: simple versus visitor restricted rest period.

    Science.gov (United States)

    Silvius-Byron, Stephanie A; Florimonte, Christine; Panganiban, Elizabeth G; Ulmer, Janice Fitzgerald

    2014-05-01

    The aim of this study was to compare a highly structured planned rest protocol that includes visitor and healthcare personnel restrictions with a simple planned rest period that encourages patients to rest during a designated time without restriction of visitors and healthcare personnel. Many hospitals acute care have begun to restrict visitors and nonessential health team interventions during specific times despite the lack of experimentally designed studies. Using a convenience sample of 52 intermediate care unit patients, a randomized experimental design study compared a highly structured planned rest protocol with restriction of visitors/healthcare personnel to a simple planned rest period without restrictions. The primary outcome variable was the patient's perceived quality of rest after a 2-hour rest period. Intermediate care patients' perception of rest and sleep during a designated rest period was similar whether elaborate rest strategies were used, including visitor and healthcare personnel restrictions, or if it was only suggested they rest and the door to their room closed. The restriction of visitors and healthcare personnel during a 2-hour rest period did not improve the patient's perception of rest or how long it took them to go to sleep.

  1. GAA triplet-repeats cause nucleosome depletion in the human genome.

    Science.gov (United States)

    Zhao, Hongyu; Xing, Yongqiang; Liu, Guoqing; Chen, Ping; Zhao, Xiujuan; Li, Guohong; Cai, Lu

    2015-08-01

    Although there have been many investigations into how trinucleotide repeats affect nucleosome formation and local chromatin structure, the nucleosome positioning of GAA triplet-repeats in the human genome has remained elusive. In this work, the nucleosome occupancy around GAA triplet-repeats across the human genome was computed statistically. The results showed a nucleosome-depleted region in the vicinity of GAA triplet-repeats in activated and resting CD4(+) T cells. Furthermore, the A-tract was frequently adjacent to the upstream region of GAA triplet-repeats and could enhance the depletion surrounding GAA triplet-repeats. In vitro chromatin reconstitution assays with GAA-containing plasmids also demonstrated that the inserted GAA triplet-repeats destabilized the ability of recombinant plasmids to assemble nucleosomes. Our results suggested that GAA triplet-repeats have lower affinity to histones and can change local nucleosome positioning. These findings may be helpful for understanding the mechanism of Friedreich's ataxia, which is associated with GAA triplet-repeats at the chromatin level.

  2. Morphological brain plasticity induced by musical expertise is accompanied by modulation of functional connectivity at rest.

    Science.gov (United States)

    Fauvel, Baptiste; Groussard, Mathilde; Chételat, Gaël; Fouquet, Marine; Landeau, Brigitte; Eustache, Francis; Desgranges, Béatrice; Platel, Hervé

    2014-04-15

    The aim of this study was to explore whether musical practice-related gray matter increases in brain regions are accompanied by modifications in their resting-state functional connectivity. 16 young musically experienced adults and 17 matched nonmusicians underwent an anatomical magnetic resonance imaging (MRI) and a resting-state functional MRI (rsfMRI). A whole-brain two-sample t test run on the T1-weighted structural images revealed four clusters exhibiting significant increases in gray matter (GM) volume in the musician group, located within the right posterior and middle cingulate gyrus, left superior temporal gyrus and right inferior orbitofrontal gyrus. Each cluster was used as a seed region to generate and compare whole-brain resting-state functional connectivity maps. The two clusters within the cingulate gyrus exhibited greater connectivity for musicians with the right prefrontal cortex and left temporal pole, which play a role in autobiographical and semantic memory, respectively. The cluster in the left superior temporal gyrus displayed enhanced connectivity with several language-related areas (e.g., left premotor cortex, bilateral supramarginal gyri). Finally, the cluster in the right inferior frontal gyrus displayed more synchronous activity at rest with claustrum, areas thought to play a role in binding sensory and motor information. We interpreted these findings as the consequence of repeated collaborative use in general networks supporting some of the memory, perceptual-motor and emotional features of musical practice. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Acute decrease in the stiffness of resting muscle belly due to static stretching.

    Science.gov (United States)

    Taniguchi, K; Shinohara, M; Nozaki, S; Katayose, M

    2015-02-01

    The purpose of the study was to examine the acute effect of static stretching exercise on the resting stiffness of gastrocnemius muscle belly. Ten healthy young adults performed standing wall stretching in dorsiflexion for 1 min at a time and repeated five times. Before and after stretching, the shear modulus was measured in medial and lateral heads of the resting gastrocnemius muscle with ultrasound shear-wave elastography. After the stretching, dorsiflexion range of motion (ROM) of the ankle joint increased (P stretching, shear modulus decreased (P stretching across muscle heads. The decrease in shear modulus returned in 20 min after stretching. In the comparison group of 10 additional subjects, the standing intervention without stretching had no influence on these measures. There was a negative correlation between dorsiflexion ROM and shear modulus in either head before and after stretching. The results demonstrate the transient decreases in the stiffness of the resting gastrocnemius muscle belly and indicate that joint flexibility is greater in individuals with lower resting stiffness of the muscle belly.

  4. Interleukin-6 directly increases glucose metabolism in resting human skeletal muscle

    DEFF Research Database (Denmark)

    Glund, Stephan; Deshmukh, Atul; Long, Yun Chau

    2007-01-01

    suggested to promote insulin-mediated glucose utilization. In this study, we determined the direct effects of IL-6 on glucose transport and signal transduction in human skeletal muscle. Skeletal muscle strips were prepared from vastus lateralis biopsies obtained from 22 healthy men. Muscle strips were...... incubated with or without IL-6 (120 ng/ml). We found that IL-6 increased glucose transport in human skeletal muscle 1.3-fold (P ... exposure increases glucose metabolism in resting human skeletal muscle. Insulin-stimulated glucose transport and insulin signaling were unchanged after IL-6 exposure....

  5. EAMJ Dec. Repeatability.indd

    African Journals Online (AJOL)

    2008-12-12

    Dec 12, 2008 ... Results:Kappa values for four-week repeatability for the wheeze and asthma questions were 0.61 ... for logistic, cultural and ethical reasons, to use ... individual with baseline forced expiratory volume in .... period is likely to also include the effects of true ... data, the writing of the manuscript or the decision.

  6. Bed Rest and Immobilization: Risk Factors for Bone Loss

    Science.gov (United States)

    ... browser. Home Osteoporosis Osteoporosis and Other Conditions Bed Rest and Immobilization: Risk Factors for Bone Loss Publication ... Line For Your Information The Impact of Bed Rest and Inactivity Some people can’t perform weight- ...

  7. In vivo delivery of DN:REST improves transcriptional changes of REST-regulated genes in HD mice.

    Science.gov (United States)

    Conforti, P; Mas Monteys, A; Zuccato, C; Buckley, N J; Davidson, B; Cattaneo, E

    2013-06-01

    Current therapeutic strategies for Huntington's disease (HD) are focused on symptom management of disease progression. Transcriptional dysregulation is one of the major characteristics in HD. REST is a transcriptional repressor that silences gene expression through binding to RE1/NRSE sites found in the regulatory regions of numerous neuronal genes. Dysregulation of REST and its targeted genes has been reported in different cell and mouse HD models, as well as in biopsies from human patients. In this work, we characterized transcriptional dysregulation associated with REST in two different HD mouse models and assessed the therapeutic effect of interfering with REST function by overexpressing a dominant-negative form (DN:REST). We show that delivery of DN:REST in the motor cortex restores brain-derived neurotrophic factor (BDNF) mRNA and protein levels by reducing endogenous REST occupancy at the Bdnf locus. Similarly, expression of other REST-regulated genes such as Synapsin I (Syn1), Proenkephalin (Penk1) and Cholinergic receptor muscarinic 4 (Chrm4) were restored to normal levels while non-REST-regulated genes were unaffected. This is the first study conducted to investigate REST's role in vivo in a neurodegenerative disease. Our data show that DN:REST in motor cortex reversed RESTs repressive effects on target genes. However, the lack of therapeutic effect on motor function suggests that a more widespread rescue of REST-regulated sites in the affected brain regions may be necessary.

  8. Framework for ReSTful Web Services in OSGi

    Science.gov (United States)

    Shams, Khawaja S.; Norris, Jeffrey S.; Powell, Mark W.; Crockett, Thomas M.; Mittman, David S.; Fox, Jason M.; Joswig, Joseph C.; Wallick, Michael N.; Torres, Recaredo J.; Rabe, Kenneth

    2009-01-01

    Ensemble ReST is a software system that eases the development, deployment, and maintenance of server-side application programs to perform functions that would otherwise be performed by client software. Ensemble ReST takes advantage of the proven disciplines of ReST (Representational State Transfer. ReST leverages the standardized HTTP protocol to enable developers to offer services to a diverse variety of clients: from shell scripts to sophisticated Java application suites

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

    Science.gov (United States)

    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.

  10. 77 FR 73911 - Flightcrew Member Duty and Rest Requirements

    Science.gov (United States)

    2012-12-12

    ... and Rest Requirements AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Availability of... Regulatory Impact Analysis of its final rule amending its existing flight, duty and rest regulations... Register as Flight Crew Member Duty and Rest Requirements on January 4, 2012. 77 FR 330. The regulations...

  11. 75 FR 63424 - Flightcrew Member Duty and Rest Requirements

    Science.gov (United States)

    2010-10-15

    ... Federal Aviation Administration 14 CFR Parts 117 and 121 RIN 2120-AJ58 Flightcrew Member Duty and Rest..., to amend its existing flight, duty and rest regulations applicable to certificate holders and their... and Rest Requirements.'' The proposed regulation recognizes the growing similarities between the types...

  12. 75 FR 62486 - Flightcrew Member Duty and Rest Requirements

    Science.gov (United States)

    2010-10-12

    ... Federal Aviation Administration 14 CFR Parts 117 and 121 RIN 2120-AJ58 Flightcrew Member Duty and Rest... flight, duty and rest regulations applicable to certificate holders and their flightcrew members. The FAA... and Rest Requirements'' (75 FR 55852). The proposed regulation recognizes the growing similarities...

  13. 46 CFR 401.451 - Pilot rest periods.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Pilot rest periods. 401.451 Section 401.451 Shipping... Rates, Charges, and Conditions for Pilotage Services § 401.451 Pilot rest periods. (a) Except as... assignments totaling more than 10 hours with no more than 2 hours rest between assignments, shall not perform...

  14. 78 FR 14166 - Clarification of Flight, Duty, and Rest Requirements

    Science.gov (United States)

    2013-03-05

    ... Federal Aviation Administration 14 CFR Parts 117 and 121 Clarification of Flight, Duty, and Rest... published a final rule on January 4, 2012, that amends the existing flight, duty and rest regulations... questions about the new flight, duty, and rest rule. This is a response to those questions. FOR FURTHER...

  15. 49 CFR 37.201 - Intermediate and rest stops.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Intermediate and rest stops. 37.201 Section 37.201... DISABILITIES (ADA) Over-the-Road Buses (OTRBs) § 37.201 Intermediate and rest stops. (a) Whenever an OTRB makes an intermediate or rest stop, a passenger with a disability, including an individual using a...

  16. Habituation to repeated stress: get used to it.

    OpenAIRE

    Grissom, Nicola; Bhatnagar, Seema

    2008-01-01

    Habituation, as described in the landmark paper by Thompson and Spencer (1966), is a form of simple, nonassociative learning in which the magnitude of the response to a specific stimulus decreases with repeated exposure to that stimulus. A variety of neuronal and behavioral responses have been shown to be subject to habituation based on the criteria presented in that paper. It has been known for several decades that the magnitude of hypothalamic-pituitary-adrenal (HPA) activation occurring in...

  17. A RESTful way to Manage Ontologies

    Science.gov (United States)

    Lowry, R. K.; Lawrence, B. N.

    2009-04-01

    In 2005 BODC implemented the first version of a vocabulary server developed as a contribution to the NERC DataGrid project. Vocabularies were managed within an RDBMS environment and accessed through a SOAP Web Service API. This was designed as a database query interface with operations targeted at designated database fields and results returned as strings. At the end of 2007 a new version of the server was released capable of serving thesauri and ontologies as well as vocabularies. The SOAP API functionality was enhanced and the output format changed to XML. In addition, a pseudo-RESTful query interface was developed directly addressing terms and lists by URLs. This is in full operational use by projects such as SeaDataNet and will run for the foreseeable future. However, operational experience has exposed shortcomings in both the API and its document payload. Other ontology servers, notably at MMI and CSIRO, are coming on-line making now the time to unify ontology management. This paper presents a RESTful API and payload document schema. It is based on the lessons learned in four years of operational vocabulary serving, provides full ontology management functionality and has the potential to form the basis for an interoperable network of distributed ontologies.

  18. Respiration patterns of resting wasps (Vespula sp.).

    Science.gov (United States)

    Käfer, Helmut; Kovac, Helmut; Stabentheiner, Anton

    2013-04-01

    We investigated the respiration patterns of wasps (Vespula sp.) in their viable temperature range (2.9-42.4°C) by measuring CO2 production and locomotor and endothermic activity. Wasps showed cycles of an interburst-burst type at low ambient temperatures (Ta31°C, CO2 emission became cyclic. With rising Ta they enhanced CO2-emission primarily by an exponential increase in respiration frequency, from 2.6 mHz at 4.7°C to 74 mHz at 39.7°C. In the same range of Ta CO2 release per cycle decreased from 38.9 to 26.4 μl g(-1)cycle(-1). A comparison of wasps with other insects showed that they are among the insects with a low respiratory frequency at a given resting metabolic rate (RMR), and a relatively flat increase of respiratory frequency with RMR. CO2 emission was always accompanied by abdominal respiration movements in all open phases and in 71.4% of the flutter phases, often accompanied by body movements. Results suggest that resting wasps gain their highly efficient gas exchange to a considerable extent via the length and type of respiration movements.

  19. Vestibular and Somatosensory Covergence in Postural Equilibrium Control: Insights from Spaceflight and Bed Rest Studies

    Science.gov (United States)

    Mulavara, A. P.; Batson, C. D.; Buxton, R. E.; Feiveson, A. H.; Kofman, I. S.; Lee, S. M. C.; Miller, C. A.; Peters, B. T.; Phillips, T.; Platts, S. H.; hide

    2014-01-01

    The goal of the Functional Task Test study is to determine the effects of space flight on functional tests that are representative of high priority exploration mission tasks and to identify the key underlying physiological factors that contribute to decrements in performance. We are currently conducting studies on both International Space Station (ISS) astronauts experiencing up to 6 months of microgravity and subjects experiencing 70 days of 6??head-down bed-rest as an analog for space flight. Bed-rest provides the opportunity for us to investigate the role of prolonged axial body unloading in isolation from the other physiological effects produced by exposure to the microgravity environment of space flight. This allows us to parse out the contribution of the body unloading somatosensory component on functional performance. Both ISS crewmembers and bed-rest subjects were tested using a protocol that evaluated functional performance along with tests of postural and locomotor control before and after space flight and bed-rest, respectively. Functional tests included ladder climbing, hatch opening, jump down, manual manipulation of objects and tool use, seat egress and obstacle avoidance, recovery from a fall, and object translation tasks. Astronauts were tested three times before flight, and on 1, 6, and 30 days after landing. Bed-rest subjects were tested three times before bed-rest and immediately after getting up from bed-rest as well as 1, 6, and 12 days after re-ambulation. A comparison of bed-rest and space flight data showed a significant concordance in performance changes across all functional tests. Tasks requiring a greater demand for dynamic control of postural equilibrium (i.e. fall recovery, seat egress/obstacle avoidance during walking, object translation, jump down) showed the greatest decrement in performance. Functional tests with reduced requirements for postural stability showed less reduction in performance. Results indicate that body unloading

  20. Body Unloading Associated with Space Flight and Bed-rest Impacts Functional Performance

    Science.gov (United States)

    Bloomberg, J. J.; Ballard, K. L.; Batson, C. D.; Buxton, R. E.; Feiveson, A. H.; Kofman, I. S.; Lee, S. M. C.; Miller, C. A.; Mulavara, A. P.; Peters, B. T.; Phillips, T.; Platts, S. H.; Ploutz-Snyder, L. L.; Reschke, M. F.; Ryder, J. W.; Stenger, M. B.; Taylor, L. C.; Wood, S. J.

    2014-01-01

    The goal of the Functional Task Test study is to determine the effects of space flight on functional tests that are representative of high priority exploration mission tasks and to identify the key underlying physiological factors that contribute to decrements in performance. Ultimately this information will be used to assess performance risks and inform the design of countermeasures for exploration class missions. We are currently conducting studies on both ISS crewmembers and on subjects experiencing 70 days of 6 degrees head-down bed-rest as an analog for space flight. Bed-rest provides the opportunity for us to investigate the role of prolonged axial body unloading in isolation from the other physiological effects produced by exposure to the microgravity environment of space flight. This allows us to parse out the contribution of the body unloading component on functional performance. In this on-going study both ISS crewmembers and bed-rest subjects were tested using an interdisciplinary protocol that evaluated functional performance and related physiological changes before and after 6 months in space and 70 days of 6? head-down bed-rest, respectively. Functional tests included ladder climbing, hatch opening, jump down, manual manipulation of objects and tool use, seat egress and obstacle avoidance, recovery from a fall, and object translation tasks. Crewmembers were tested three times before flight, and on 1, 6 and 30 days after landing. Bed-rest subjects were tested three times before bed-rest and immediately after getting up from bed-rest as well as 1, 6 and 12 days after reambulation. A comparison of bed-rest and space flight data showed a significant concordance in performance changes across all functional tests. Tasks requiring a greater demand for dynamic control of postural equilibrium (i.e. fall recovery, seat egress/obstacle avoidance during walking, object translation, jump down) showed the greatest decrement in performance. Functional tests with

  1. Directionality switchable gain stabilized linear repeater

    Science.gov (United States)

    Ota, Takayuki; Ohmachi, Tadashi; Aida, Kazuo

    2004-10-01

    We propose a new approach to realize a bidirectional linear repeater suitable for future optical internet networks and fault location in repeater chain with OTDR. The proposed approach is the linear repeater of simple configuration whose directionality is rearranged dynamically by electrical control signal. The repeater is composed of a magneto-optical switch, a circulator, a dynamically gain stabilized unidirectional EDFA, and control circuits. The repeater directionality is rearranged as fast as 0.1ms by an electrical control pulse. It is experimentally confirmed that OTDR with the directionality switchable repeater is feasible for repeater chain. The detailed design and performance of the repeater are also discussed, including the multi-pass interference (MPI) which may arise in the proposed repeater, the effect of the MPI on SNR degradation of the repeater chain and the feed-forward EDFA gain control circuit.

  2. Exposure to captan in fruit growing.

    Science.gov (United States)

    de Cock, J; Heederik, D; Kromhout, H; Boleij, J S; Hoek, F; Wegh, H; Tjoe Ny, E

    1998-03-01

    This study characterized occupational exposure to pesticides in fruit growing in The Netherlands to assess determinants of exposure. Large-scale exposure surveys were carried out during application of pesticides and during reentry activities. Data on contamination inside the fruit growers' homes were obtained, and total potential exposure for the fruit grower and his family during the growing and harvesting season was estimated. Repeated measurements on the same subject were collected to study components of exposure variability. Relative contribution of the respiratory route and different skin sites to total exposure were assessed. Captan was used as a marker for exposure. Inhalable dust exposure was measured with a personal monitor and potential dermal exposure with skin pads and hand rinsing. Dislodgeable foliar residue was measured by taking leaf punches. For respiratory exposure and potential dermal exposure, differences were observed between several tasks. Workers were categorized according to tasks performed depending on the exposure measure(s) (e.g., hands, forehead, inhalable dust) considered relevant for a specific study purpose. In general, within-worker variability of all exposure measurements was larger than between-worker variability. Variability in dermal exposure on the same body location was small relative to variability between different body locations. Differences in total exposure, including exposure inside the home, between the fruit grower and the son were small. Exposure of the wife was two to three times lower than for the fruit grower and the son. As exposure per unit of time was in the same order of magnitude for different tasks, individual time spent on these tasks is crucial for estimating total potential exposure. Repeated measurements are necessary to estimate individual exposure accurately because of the large within-worker variability.

  3. Measurement-based quantum repeaters

    CERN Document Server

    Zwerger, M; Briegel, H J

    2012-01-01

    We introduce measurement-based quantum repeaters, where small-scale measurement-based quantum processors are used to perform entanglement purification and entanglement swapping in a long-range quantum communication protocol. In the scheme, pre-prepared entangled states stored at intermediate repeater stations are coupled with incoming photons by simple Bell-measurements, without the need of performing additional quantum gates or measurements. We show how to construct the required resource states, and how to minimize their size. We analyze the performance of the scheme under noise and imperfections, with focus on small-scale implementations involving entangled states of few qubits. We find measurement-based purification protocols with significantly improved noise thresholds. Furthermore we show that already resource states of small size suffice to significantly increase the maximal communication distance. We also discuss possible advantages of our scheme for different set-ups.

  4. A Repeating Fast Radio Burst

    CERN Document Server

    Spitler, L G; Hessels, J W T; Bogdanov, S; Brazier, A; Camilo, F; Chatterjee, S; Cordes, J M; Crawford, F; Deneva, J; Ferdman, R D; Freire, P C C; Kaspi, V M; Lazarus, P; Lynch, R; Madsen, E C; McLaughlin, M A; Patel, C; Ransom, S M; Seymour, A; Stairs, I H; Stappers, B W; van Leeuwen, J; Zhu, W W

    2016-01-01

    Fast Radio Bursts are millisecond-duration astronomical radio pulses of unknown physical origin that appear to come from extragalactic distances. Previous follow-up observations have failed to find additional bursts at the same dispersion measures (i.e. integrated column density of free electrons between source and telescope) and sky position as the original detections. The apparent non-repeating nature of the fast radio bursts has led several authors to hypothesise that they originate in cataclysmic astrophysical events. Here we report the detection of ten additional bursts from the direction of FRB121102, using the 305-m Arecibo telescope. These new bursts have dispersion measures and sky positions consistent with the original burst. This unambiguously identifies FRB121102 as repeating and demonstrates that its source survives the energetic events that cause the bursts. Additionally, the bursts from FRB121102 show a wide range of spectral shapes that appear to be predominantly intrinsic to the source and wh...

  5. Assessment of radiographic film repeats rate and its related causes within hospitals in Sari during 2008

    Directory of Open Access Journals (Sweden)

    Gholamreza Fallah Mohamadi

    2009-01-01

    Full Text Available (Received 8 April, 2009 ; Accepted 27 May, 2009AbstractBackground and purpose: Radiographic film repeat rate assessment is performed to appropriate profiting of existence resources in therapeutic wards. Multiple exposures of x-ray generators due to repeated radiographic examination can lead to amortization of the radiographic facilities and decrease their longevity and also increases the cost of facilities repair. On the other hand, its therapeutic services are necessary to be carried out for patients as soon as possible. Recognition of radiographic film repeat rate and its related causes will help to eliminate the problems and are cost effective.Materials and methods: In this descriptive study, samples were garnered with data collection and non random model during three months in eight radiographic rooms and four darkrooms belonging to four governmental hospitals, namely Imam Khomeini, Booali Sina, Fatemh Zahra and Zare in Sari. All rejected radiographic films were seen by resident experts in each center and information was entered into designed forms. Radiographic repeat rates were calculated through data available from all recipients and the number of used films. In this article, related causes responsible for repeated radiographic examination including errors in selection of exposure factors (over exposure and under exposure, positioning, centering, film size, equipment, processing or darkroom, movement and others were assessed.Results: In four hospitals, 36,758 films were received during investigation and the number of repeated films was 2,155 (5.9 % were estimated as radiographic repeat rate. The maximum repeat rate belonged to Booali sina Hospital (7.2 % and the minimum one was Zare Hospital (0.7 %. The most important causes were due to over exposure selection (1.4 % and the least one was due to improper selection of film size (0.08 %. The percentage of other factors include, under exposure selection (1.12%, centering (0.92%, others (0

  6. The Ensembl REST API: Ensembl Data for Any Language.

    Science.gov (United States)

    Yates, Andrew; Beal, Kathryn; Keenan, Stephen; McLaren, William; Pignatelli, Miguel; Ritchie, Graham R S; Ruffier, Magali; Taylor, Kieron; Vullo, Alessandro; Flicek, Paul

    2015-01-01

    We present a Web service to access Ensembl data using Representational State Transfer (REST). The Ensembl REST server enables the easy retrieval of a wide range of Ensembl data by most programming languages, using standard formats such as JSON and FASTA while minimizing client work. We also introduce bindings to the popular Ensembl Variant Effect Predictor tool permitting large-scale programmatic variant analysis independent of any specific programming language. The Ensembl REST API can be accessed at http://rest.ensembl.org and source code is freely available under an Apache 2.0 license from http://github.com/Ensembl/ensembl-rest. © The Author 2014. Published by Oxford University Press.

  7. Repeatability of Harris Corner Detector

    Institute of Scientific and Technical Information of China (English)

    HU Lili

    2003-01-01

    Interest point detectors are commonly employed to reduce the amount of data to be processed. The ideal interest point detector would robustly select those features which are most appropriate or salient for the application and data at hand. This paper shows that interest points are geometrically stable under different transformations.This property makes interest points very successful in the context of image matching. To measure this property quantatively, we introduce a evaluation criterion: repeatability rate.

  8. REST represses a subset of the pancreatic endocrine differentiation program

    DEFF Research Database (Denmark)

    Martin, David; Kim, Yung-Hae; Sever, Dror

    2015-01-01

    To contribute to devise successful beta-cell differentiation strategies for the cure of Type 1 diabetes we sought to uncover barriers that restrict endocrine fate acquisition by studying the role of the transcriptional repressor REST in the developing pancreas. Rest expression is prevented...... in neurons and in endocrine cells, which is necessary for their normal function. During development, REST represses a subset of genes in the neuronal differentiation program and Rest is down-regulated as neurons differentiate. Here, we investigate the role of REST in the differentiation of pancreatic...... endocrine cells, which are molecularly close to neurons. We show that Rest is widely expressed in pancreas progenitors and that it is down-regulated in differentiated endocrine cells. Sustained expression of REST in Pdx1(+) progenitors impairs the differentiation of endocrine-committed Neurog3...

  9. Resting state brain activity and functional brain mapping

    Institute of Scientific and Technical Information of China (English)

    Zhao Xiaohu; Wang Peijun; Tang Xiaowei

    2007-01-01

    Functional brain imaging studies commonly use either resting or passive task states as their control conditions, and typically identify the activation brain region associated with a specific task by subtracting the resting from the active task conditions. Numerous studies now suggest, however, that the resting state may not reflect true mental "rest" conditions. The mental activity that occurs during"rest" might therefore greatly influence the functional neuroimaging observations that are collected through the usual subtracting analysis strategies. Exploring the ongoing mental processes that occur during resting conditions is thus of particular importance for deciphering functional brain mapping results and obtaining a more comprehensive understanding of human brain functions. In this review article, we will mainly focus on the discussion of the current research background of functional brain mapping at resting state and the physiological significance of the available neuroimaging data.

  10. Recreational resources - basement for active rest of a man.

    Directory of Open Access Journals (Sweden)

    Zaytzev V.P.

    2011-03-01

    Full Text Available The theoretical aspects of active rest resources of Ukraine, their classification and ball estimation are presented: medical and biological, psychological, technological. The special complication in the estimation of active rest resources consists of that they are necessary to be examined both from position of organizers of rest and from position of holiday-makers. Importance of active rest a man (student is shown in sanatorium-resort terms. Therefore two basic tasks cost before counsels: medical service of patients (second prophylaxis and health rest. The active rest resources of Crimea are as an example considered, Zakarpatskoy and Kharkov areas. In every region there are the features of active rest resources which lift the physical and psychical health of man.

  11. Exercise thermoregulation after 14 days of bed rest

    Science.gov (United States)

    Greenleaf, J. E.; Reese, R. D.

    1980-01-01

    The effects of bed rest and exercise training during bed rest on body temperature and thermoregulatory responses at rest and during exercise are investigated. Seven male subjects underwent three two-week periods of bed rest during which isometric, isotonic, or no exercises were performed, separated by two ambulatory control periods and preceded by a two-week control period, during which they exercised regularly. Rectal and mean skin temperatures and sweating responses were determined during 70-min submaximal supine exercise during the bed rest and recovery periods. Measurements reveal a reduction in basal oral temperature during the control-recovery periods, with a relatively constant level during bed rest periods, and a significant increase in the rectal temperature elavation brought on by exercise following all three bed-rest regimes. It is concluded that the excessive increase in rectal temperature could be influenced by changes in skin heat conductance or the inhibition of sweating.

  12. Study on the Back Rest System of Looms

    Institute of Scientific and Technical Information of China (English)

    陈革; 毛立民; 周亚勤; 袁立新

    2004-01-01

    Periodic variations of warp tension during a weaving cycle result in corresponding change of back rest position, and the oscillation of back rest affects the fluctuation of warp yarn in return. A mechanical model of back rest system of looms is presented on basis of auto control theory, and the factors affecting the dynamic performance of the back rest are analyzed. In the model, warp yarn is regarded as a viscoelastic medium, and the adjustable parameters and the adjusting range of the back rest system are increased, so the ioom's applicability for the fabric's variety is enlanced.Finally, the methods of designing and adjusting the back rest are discussed, and a trend of back rest system development is given.

  13. Longitudinal Changes of Resting-State Functional Connectivity during Motor Recovery after Stroke

    Science.gov (United States)

    Park, Chang-hyun; Chang, Won Hyuk; Ohn, Suk Hoon; Kim, Sung Tae; Bang, Oh Young; Pascual-Leone, Alvaro; Kim, Yun-Hee

    2013-01-01

    Background and Purpose Functional magnetic resonance imaging (fMRI) studies could provide crucial information on the neural mechanisms of motor recovery in stroke patients. Resting-state fMRI is applicable to stroke patients who are not capable of proper performance of the motor task. In this study, we explored neural correlates of motor recovery in stroke patients by investigating longitudinal changes in resting-state functional connectivity of the ipsilesional primary motor cortex (M1). Methods A longitudinal observational study using repeated fMRI experiments was conducted in 12 patients with stroke. Resting-state fMRI data were acquired four times over a period of 6 months. Patients participated in the first session of fMRI shortly after onset, and thereafter in subsequent sessions at 1, 3, and 6 months after onset. Resting-state functional connectivity of the ipsilesional M1 was assessed and compared with that of healthy subjects. Results Compared with healthy subjects, patients demonstrated higher functional connectivity with the ipsilesional frontal and parietal cortices, bilateral thalamus, and cerebellum. Instead, functional connectivity with the contralesional M1 and occipital cortex were decreased in stroke patients. Functional connectivity between the ipsilesional and contralesional M1 showed the most asymmetry at 1 month after onset to the ipsilesional side. Functional connectivity of the ipsilesional M1 with the contralesional thalamus, supplementary motor area, and middle frontal gyrus at onset was positively correlated with motor recovery at 6 months after stroke. Conclusions Resting-state fMRI elicited distinctive but comparable results with previous task-based fMRI, presenting complementary and practical values for use in the study of stroke patients. PMID:21441147

  14. Fetal outcome in repeat cervical encirclage in same pregnancy

    Directory of Open Access Journals (Sweden)

    Nirmala Sharma

    2013-08-01

    Full Text Available A 30 year old sixth gravida patient having five spontaneous abortions between fifth and sixth months of amenorrhea. Patient had an incompetent cervix, cervical cerclage was done at 14 weeks of gestation by Mc Donald’s method. Pregnancy was uneventful for more than one month and patient reported back with complaints of bleeding per vaginum, and pain abdomen, cerclage was removed by duty doctor in emergency, but pains subsided. Ultrasound was done revealing low lying placenta reaching upto the os with 22 weeks live intrauterine pregnancy. Repeat transvaginal cervical cerclage was decided and done in similar manner. Patient was kept indoor on bed rest, tocolytics, antibiotics and progesterone support till the time of delivery. At 30 weeks pregnancy ultrasound revealed low amniotic fluid index (1.2 for which amino acid infusion was administered. Later on patient developed bleeding & leaking per vaginum with cervical dilatation, so immediate cesarean section decided and corticosteroid administered for fetal lung maturity, emergency cesarean section was done. In follow up mother and baby were absolutely healthy. The pregnancy outcome is significantly improved even after repeat cervical cerclage in same pregnancy and if there is a need for repeat cervical cerclage during same pregnancy it should be done to improve fetal salvage. [Int J Reprod Contracept Obstet Gynecol 2013; 2(4.000: 728-729

  15. Radiation Exposure

    Science.gov (United States)

    ... on to any children you have after the exposure. A lot of radiation over a short period, ... skin burns and reduced organ function. If the exposure is large enough, it can cause premature aging ...

  16. [Resting heart rate and cardiovascular disease].

    Science.gov (United States)

    Brito Díaz, Buenaventura; Alemán Sánchez, José Juan; Cabrera de León, Antonio

    2014-07-07

    Heart rate reflects autonomic nervous system activity. Numerous studies have demonstrated that an increased heart rate at rest is associated with cardiovascular morbidity and mortality as an independent risk factor. It has been shown a link between cardiac autonomic balance and inflammation. Thus, an elevated heart rate produces a micro-inflammatory response and is involved in the pathogenesis of endothelial dysfunction. In turn, decrease in heart rate produces benefits in congestive heart failure, myocardial infarction, atrial fibrillation, obesity, hyperinsulinemia, insulin resistance, and atherosclerosis. Alteration of other heart rate-related parameters, such as their variability and recovery after exercise, is associated with risk of cardiovascular events. Drugs reducing the heart rate (beta-blockers, calcium antagonists and inhibitors of If channels) have the potential to reduce cardiovascular events. Although not recommended in healthy subjects, interventions for reducing heart rate constitute a reasonable therapeutic goal in certain pathologies. Copyright © 2013 Elsevier España, S.L. All rights reserved.

  17. Online Learning of Rested and Restless Bandits

    CERN Document Server

    Tekin, Cem

    2011-01-01

    In this paper we study the online learning problem involving rested and restless multiarmed bandits with multiple plays. The system consists of a single player/user and a set of K finite-state discrete-time Markov chains (arms) with unknown state spaces and statistics. At each time step the player can play M arms. The objective of the user is to decide for each step which M of the K arms to play over a sequence of trials so as to maximize its long term reward. The restless multiarmed bandit is particularly relevant to the application of opportunistic spectrum access (OSA), where a (secondary) user has access to a set of K channels, each of time-varying condition as a result of random fading and/or certain primary users' activities.

  18. Origin and fate of repeats in bacteria.

    Science.gov (United States)

    Achaz, G; Rocha, E P C; Netter, P; Coissac, E

    2002-07-01

    We investigated 53 complete bacterial chromosomes for intrachromosomal repeats. In previous studies on eukaryote chromosomes, we proposed a model for the dynamics of repeats based on the continuous genesis of tandem repeats, followed by an active process of high deletion rate, counteracted by rearrangement events that may prevent the repeats from being deleted. The present study of long repeats in the genomes of Bacteria and Archaea suggests that our model of interspersed repeats dynamics may apply to them. Thus the duplication process might be a consequence of very ancient mechanisms shared by all three domains. Moreover, we show that there is a strong negative correlation between nucleotide composition bias and the repeat density of genomes. We hypothesise that in highly biased genomes, non-duplicated small repeats arise more frequently by random effects and are used as primers for duplication mechanisms, leading to a higher density of large repeats.

  19. Tempat Kedudukan Rest Lingual dalam Pembuatan Gigi Tiruan Sebagian Lepas Kerangka Logam Lingual Rest Seat in Removable Partial Denture

    Directory of Open Access Journals (Sweden)

    Armida Sofyanis

    2015-09-01

    Full Text Available In certain cases, lingual rest is needed to provide better retention for RPD. Lingual rest is a cingulum rest placed on the lower jaw in RPD design. It is used as an indirect retainer. To make the rest fit best, a good rest seat should be prepared in the cingulum. The outline form of the lingual rest is a half moon shaped with a smooth curve from one marginal ridge to the other, crossing the center of the tooth. The rest seat itself should be V shaped, and the depth is 1 - 1 1/2mm. In this situation, one of four options should be considered i.e.: fabricate a cast veneer crown, or a three quarter crown to place a lingual pin-lay, or put a small amalgam restoration in the base of the preparation when the dentin has been touched.  

  20. A comparison of pairs figure skaters in repeated jumps.

    Science.gov (United States)

    Sands, William A; Kimmel, Wendy L; McNeal, Jeni R; Murray, Steven Ross; Stone, Michael H

    2012-01-01

    Trends in pairs figure skating have shown that increasingly difficult jumps have become an essential aspect of high-level performance, especially in the latter part of a competitive program. We compared a repeated jump power index in a 60 s repeated jump test to determine the relationship of repeated jump test to competitive rank and to measure 2D hip, knee, and ankle angles and angular velocities at 0, 20, 40, and 60 s. Eighteen National Team Pairs Figure Skaters performed a 60 s repeated jump test on a large switch-mat with timing of flight and ground durations and digital video recording. Each 60-s period was divided into 6, 10-s intervals, with power indexes (W/kg) calculated for each 10-s interval. Power index by 10-s interval repeated measures ANOVAs (RMANOVA) showed that males exceeded females at all intervals, and the highest power index interval was during 10 to 20 s for both sexes. RMANOVAs of angles and angular velocities showed main effects for time only. Power index and jumping techniques among figure skaters showed rapid and steady declines over the test duration. Power index can predict approximately 50% of competitive rank variance, and sex differences in jumping technique were rare. Key pointsThe repeated jumps test can account for about 50% of the variance in pairs ranks.Changes in technique are largely due to fatigue, but the athletes were able to maintain a maximum flexion knee angle very close to the desired 90 degrees. Changes in angular velocity and jump heights occurred as expected, again probably due to fatigue.As expected from metabolic information, the athletes' power indexes peak around 20s and decline thereafter. Coaches should be aware of this time as a boundary beyond which fatigue becomes more manifest, and use careful choreographic choices to provide rest periods that are disguised as less demanding skating elements to afford recovery.The repeated jumps test may be a helpful off-ice test of power-endurance for figure skaters.

  1. REST and stress resistance in ageing and Alzheimer's disease

    Science.gov (United States)

    Lu, Tao; Aron, Liviu; Zullo, Joseph; Pan, Ying; Kim, Haeyoung; Chen, Yiwen; Yang, Tun-Hsiang; Kim, Hyun-Min; Drake, Derek; Liu, X. Shirley; Bennett, David A.; Colaiácovo, Monica P.; Yankner, Bruce A.

    2014-03-01

    Human neurons are functional over an entire lifetime, yet the mechanisms that preserve function and protect against neurodegeneration during ageing are unknown. Here we show that induction of the repressor element 1-silencing transcription factor (REST; also known as neuron-restrictive silencer factor, NRSF) is a universal feature of normal ageing in human cortical and hippocampal neurons. REST is lost, however, in mild cognitive impairment and Alzheimer's disease. Chromatin immunoprecipitation with deep sequencing and expression analysis show that REST represses genes that promote cell death and Alzheimer's disease pathology, and induces the expression of stress response genes. Moreover, REST potently protects neurons from oxidative stress and amyloid β-protein toxicity, and conditional deletion of REST in the mouse brain leads to age-related neurodegeneration. A functional orthologue of REST, Caenorhabditis elegans SPR-4, also protects against oxidative stress and amyloid β-protein toxicity. During normal ageing, REST is induced in part by cell non-autonomous Wnt signalling. However, in Alzheimer's disease, frontotemporal dementia and dementia with Lewy bodies, REST is lost from the nucleus and appears in autophagosomes together with pathological misfolded proteins. Finally, REST levels during ageing are closely correlated with cognitive preservation and longevity. Thus, the activation state of REST may distinguish neuroprotection from neurodegeneration in the ageing brain.

  2. Improving repeatability by improving quality

    Energy Technology Data Exchange (ETDEWEB)

    Ronen, Shuki; Ackers, Mark; Schlumberger, Geco-Prakla; Brink, Mundy

    1998-12-31

    Time lapse (4-D) seismic is a promising tool for reservoir characterization and monitoring. The method is apparently simple: to acquire data repeatedly over the same reservoir, process and interpret the data sets, then changes between the data sets indicate changes in the reservoir. A problem with time lapse seismic data is that reservoirs are a relatively small part of the earth and important reservoir changes may cause very small differences to the time lapse data. The challenge is to acquire and process economical time lapse data such that reservoir changes can be detected above the noise of varying acquisition and environment. 7 refs., 9 figs.

  3. Coordinated hybrid automatic repeat request

    KAUST Repository

    Makki, Behrooz

    2014-11-01

    We develop a coordinated hybrid automatic repeat request (HARQ) approach. With the proposed scheme, if a user message is correctly decoded in the first HARQ rounds, its spectrum is allocated to other users, to improve the network outage probability and the users\\' fairness. The results, which are obtained for single- and multiple-antenna setups, demonstrate the efficiency of the proposed approach in different conditions. For instance, with a maximum of M retransmissions and single transmit/receive antennas, the diversity gain of a user increases from M to (J+1)(M-1)+1 where J is the number of users helping that user.

  4. Glycaemic & insulinaemic responses in men at rest following sago meal.

    Science.gov (United States)

    Ahmad, Hishamuddin; Singh, Rabindarjeet; Ghosh, Asok Kumar

    2009-08-01

    Sago (Metroxylin sagu) is one of the main sources of native starch. In Malaysia sago dishes are commonly eaten with sugar. However, other societies use sago as a staple food item instead of rice or potato. The study was undertaken to investigate the effect of ingestion of different physical forms of sago supplementation on plasma glucose and plasma insulin responses, as compared to the white bread supplementation in man, during resting condition. Twelve male subjects were given in random order with three different physical forms of a sago supplementation, viz., sago porridge (SR), sago paste (SP), sago gel (SG) and white bread (WB) which was repeated on separate days, at least, 1 wk apart after an overnight fast. Venous blood samples were collected at baseline and at 15, 30, 45, 60, 90, 120, 150 and 180 min after the start of each meal and were analyzed for plasma levels of glucose and insulin. Plasma glucose reached peak at 45 min after supplementation of various sago meals. Plasma glucose area under the curve (AUC) for WB was significantly lower than SG but not significantly different from SR and SP. No significant difference was observed in plasma glucose AUC among the three sago meals. Plasma insulin AUC for SG was significantly higher than WB and SR. All three sago meals tested were not significantly different in their glycaemic responses. However, the insulin response was significantly lower for SR compared to SP and SG. The present findings suggest that any one of the three sago meals tested in this study may be used to elucidate the effect of sago starch ingestion on exercise performance in the heat. Sago paste and sago porridge may be used for supplementation before and during exercise, whereas, sago gel may be used after endurance exercise during recovery process.

  5. Effects of repeated consumption on sensory-enhanced satiety.

    Science.gov (United States)

    Yeomans, Martin R; McCrickerd, Keri; Brunstrom, Jeffrey M; Chambers, Lucy

    2014-03-28

    Previous research has suggested that sensory characteristics of a drink modify the acute satiating effects of its nutrients, with enhanced satiety being evident when a high-energy drink was thicker and tasted creamier. The present study tested whether this modulation of satiety by sensory context was altered by repeated consumption. Participants (n 48) consumed one of four drinks mid-morning on seven non-consecutive days, with satiety responses being measured pre-exposure (day 1), post-exposure (day 6) and at a 1-month follow-up. The drinks combined two levels of energy (lower energy (LE), 326 kJ and higher energy, 1163 kJ) with two levels of satiety-predictive sensory characteristics (low sensory (LS) or enhanced sensory). Test lunch intake 90 min after drink consumption depended on both the energy content and sensory characteristics of the drink before exposure, but on the energy content alone after exposure and at the follow-up. The largest change was an increase in test meal intake over time in the LE/LS condition. The effects on intake were reflected in appetite ratings, with rated hunger and expected filling affected by sensory characteristics and energy content pre-exposure, but were largely determined by energy content post-exposure and at the follow-up. In contrast, a measure of expected satiety reflected sensory characteristics regardless of energy content on all the three test days. Overall, these data suggest that some aspects of the sensory modulation of satiety are changed by repeated consumption, with covert energy becoming more effective in suppressing appetite over time, but also suggest that these behavioural changes are not readily translated into expectations of satiety.

  6. Crowding by a repeating pattern.

    Science.gov (United States)

    Rosen, Sarah; Pelli, Denis G

    2015-01-01

    Theinability to recognize a peripheral target among flankers is called crowding. For a foveal target, crowding can be distinguished from overlap masking by its sparing of detection, linear scaling with eccentricity, and invariance with target size.Crowding depends on the proximity and similarity of the flankers to the target. Flankers that are far from or dissimilar to the target do not crowd it. On a gray page, text whose neighboring letters have different colors, alternately black and white, has enough dissimilarity that it might escape crowding. Since reading speed is normally limited by crowding, escape from crowding should allow faster reading. Yet reading speed is unchanged (Chung & Mansfield, 2009). Why? A recent vernier study found that using alternating-color flankers produces strong crowding (Manassi, Sayim, & Herzog, 2012). Might that effect occur with letters and reading? Critical spacing is the minimum center-to-center target-flanker spacing needed to correctly identify the target. We measure it for a target letter surrounded by several equidistant flanker letters of the same polarity, opposite polarity, or mixed polarity: alternately white and black. We find strong crowding in the alternating condition, even though each flanker letter is beyond its own critical spacing (as measured in a separate condition). Thus a periodic repeating pattern can produce crowding even when the individual elements do not. Further, in all conditions we find that, once a periodic pattern repeats (two cycles), further repetition does not affect critical spacing of the innermost flanker.

  7. Exposure to vibrations in wine growing

    Directory of Open Access Journals (Sweden)

    Domenico Pessina

    2013-09-01

    Full Text Available Apart the winter period, the activity in specialized agricultural cultivations (i.e. wine- and fruit-growing is distributed for a long period of the year. Some tasks, such as pesticide distribution, are repeated several times during the growing season. On the other hand, mechanization is one of the pillars on which is based the modern agriculture management. As a consequence, in wine growing the tractor driver has to be considered a worker potentially subjected to high level of vibrations, due to the poor machinery conditions often encountered, and sometimes to the rough soil surface of the vineyard combined with the high travelling speed adopted in carrying out many operations. About vibrations, the Italian Decree 81/08 basically refers to the European Directive 2002/44/CE, that provides some very strict limits of exposure, both for whole body and hand-arm districts. In Oltrepo pavese, a large hilly area located the south part of the Pavia province (Lombardy - Italy wine growing is the main agricultural activity; for this reason, a detailed survey on the vibration levels recorded at the tractor driver’s seat was carried out, in order to ascertain the real risk to which the operators are exposed. The activity in wine growing has been classified into 6 groups of similar tasks, as follows: 1. canopy management: pruning, trimming, binding, stripping, etc.; 2. soil management: harrowing, hoeing, subsoiling etc.; 3. inter-row management: chopping of pruning , pinching, grass mowing, etc.; 4. crop protection: pesticides and fungicides distribution, sulfidation, foliar fertilization, etc.; 5. grape harvesting: manual or mechanical; 6. transport: from the vineyard to the cellar. For each group of tasks, the vibration levels on 3 the traditional axes (x, y and z were recorded, and then an exposure time was calculated for each of them, in order to ascertain the risk level in comparison to what provided by the dedicated standard. Finally, a detailed

  8. Automatization and familiarity in repeated checking

    NARCIS (Netherlands)

    Dek, Eliane C P; van den Hout, Marcel A.; Giele, Catharina L.; Engelhard, Iris M.

    2014-01-01

    Repeated checking paradoxically increases memory uncertainty. This study investigated the underlying mechanism of this effect. We hypothesized that as a result of repeated checking, familiarity with stimuli increases, and automatization of the checking procedure occurs, which should result in decrea

  9. CDC Vital Signs: Preventing Repeat Teen Births

    Science.gov (United States)

    ... file Error processing SSI file Preventing Repeat Teen Births Recommend on Facebook Tweet Share Compartir On this ... Too many teens, ages 15–19, have repeat births. Nearly 1 in 5 births to teens, ages ...

  10. Higher resting heart rate variability predicts skill in expressing some emotions.

    Science.gov (United States)

    Tuck, Natalie L; Grant, Rosemary C I; Sollers, John J; Booth, Roger J; Consedine, Nathan S

    2016-12-01

    Vagally mediated heart rate variability (vmHRV) is a measure of cardiac vagal tone, and is widely viewed as a physiological index of the capacity to regulate emotions. However, studies have not directly tested whether vmHRV is associated with the ability to facially express emotions. In extending prior work, the current report tested links between resting vmHRV and the objectively assessed ability to facially express emotions, hypothesizing that higher vmHRV would predict greater expressive skill. Eighty healthy women completed self-reported measures, before attending a laboratory session in which vmHRV and the ability to express six emotions in the face were assessed. A repeated measures analysis of variance revealed a marginal main effect for vmHRV on skill overall; individuals with higher resting vmHRV were only better able to deliberately facially express anger and interest. Findings suggest that differences in resting vmHRV are associated with the objectively assessed ability to facially express some, but not all, emotions, with potential implications for health and well-being. © 2016 Society for Psychophysiological Research.

  11. Effects of Physical Exercise on Individual Resting State EEG Alpha Peak Frequency

    Directory of Open Access Journals (Sweden)

    Boris Gutmann

    2015-01-01

    Full Text Available Previous research has shown that both acute and chronic physical exercises can induce positive effects on brain function and this is associated with improvements in cognitive performance. However, the neurophysiological mechanisms underlying the beneficial effects of exercise on cognitive processing are not well understood. This study examined the effects of an acute bout of physical exercise as well as four weeks of exercise training on the individual resting state electroencephalographic (EEG alpha peak frequency (iAPF, a neurophysiological marker of the individual’s state of arousal and attention, in healthy young adults. The subjects completed a steady state exercise (SSE protocol or an exhaustive exercise (EE protocol, respectively, on two separate days. EEG activity was recorded for 2 min before exercise, immediately after exercise, and after 10 min of rest. All assessments were repeated following four weeks of exercise training to investigate whether an improvement in physical fitness modulates the resting state iAPF and/or the iAPF response to an acute bout of SSE and EE. The iAPF was significantly increased following EE (P=0.012 but not following SSE. It is concluded that the iAPF is increased following intense exercise, indicating a higher level of arousal and preparedness for external input.

  12. CyREST: Turbocharging Cytoscape Access for External Tools via a RESTful API.

    Science.gov (United States)

    Ono, Keiichiro; Muetze, Tanja; Kolishovski, Georgi; Shannon, Paul; Demchak, Barry

    2015-01-01

    As bioinformatic workflows become increasingly complex and involve multiple specialized tools, so does the difficulty of reliably reproducing those workflows. Cytoscape is a critical workflow component for executing network visualization, analysis, and publishing tasks, but it can be operated only manually via a point-and-click user interface. Consequently, Cytoscape-oriented tasks are laborious and often error prone, especially with multistep protocols involving many networks. In this paper, we present the new cyREST Cytoscape app and accompanying harmonization libraries. Together, they improve workflow reproducibility and researcher productivity by enabling popular languages (e.g., Python and R, JavaScript, and C#) and tools (e.g., IPython/Jupyter Notebook and RStudio) to directly define and query networks, and perform network analysis, layouts and renderings. We describe cyREST's API and overall construction, and present Python- and R-based examples that illustrate how Cytoscape can be integrated into large scale data analysis pipelines. cyREST is available in the Cytoscape app store (http://apps.cytoscape.org) where it has been downloaded over 1900 times since its release in late 2014.

  13. Resting-state qEEG predicts rate of second language learning in adults.

    Science.gov (United States)

    Prat, Chantel S; Yamasaki, Brianna L; Kluender, Reina A; Stocco, Andrea

    2016-01-01

    Understanding the neurobiological basis of individual differences in second language acquisition (SLA) is important for research on bilingualism, learning, and neural plasticity. The current study used quantitative electroencephalography (qEEG) to predict SLA in college-aged individuals. Baseline, eyes-closed resting-state qEEG was used to predict language learning rate during eight weeks of French exposure using an immersive, virtual scenario software. Individual qEEG indices predicted up to 60% of the variability in SLA, whereas behavioral indices of fluid intelligence, executive functioning, and working-memory capacity were not correlated with learning rate. Specifically, power in beta and low-gamma frequency ranges over right temporoparietal regions were strongly positively correlated with SLA. These results highlight the utility of resting-state EEG for studying the neurobiological basis of SLA in a relatively construct-free, paradigm-independent manner.

  14. Semiprecision rest system for distal-extension removable partial dentures.

    Science.gov (United States)

    Zinner, I D

    1979-07-01

    The history of the nonlocking type of intracoronal semiprecision rest has been traced from its origins with Neurohr in 1930, up to its present use as the Thompson dowel rest. The advantages of the use of this deep rest design and the clasp arm design for primary retention have been discussed. The Blatterfein modification of the lingual clasp arm has been introduced to overcome the problems of breakage and lack of stabilization which are present with the Thompson, Van Dam, and Wands designs.

  15. Differences among Elite Female Rowers Regarding Carbohydrate Consumption at Rest

    OpenAIRE

    BADAU, Dana; TOMESCU, VALERIU; BADAU, Adela; MARTIN, Ștefan Adrian

    2016-01-01

    Backround: The objective of this study was interpreting the reported differences within carbohydrate consumption at rest, in female rowing groups. Method: We conducted a cross-sectional study, on a group of elite rowing athletes, monitoring carbohydrate consumption at rest. 34 subjects, divided in 3 groups of activities (senior, youth, junior) took part in this study being monitored through Cosmed Quark CPET device. Results: The average amount of carbohydrates consumed at rest among the group...

  16. Developing RESTful web services with Jersey 2.0

    CERN Document Server

    Gulabani, Sunil

    2013-01-01

    The book will follow a standard tutorial approach and will teach readers how to use the Jersey API for creating RESTful web services.This book is intended for Java EE developers who are building applications on the REST architecture. This is a quick, hands-on guide for learning JAX-RS 2.0. Developers should have some knowledge about RESTful web services but it's not essential to know JAX-RS 1.0.

  17. Expanded complexity of unstable repeat diseases

    OpenAIRE

    Polak, Urszula; McIvor, Elizabeth; Dent, Sharon Y.R.; Wells, Robert D.; Napierala, Marek.

    2012-01-01

    Unstable Repeat Diseases (URDs) share a common mutational phenomenon of changes in the copy number of short, tandemly repeated DNA sequences. More than 20 human neurological diseases are caused by instability, predominantly expansion, of microsatellite sequences. Changes in the repeat size initiate a cascade of pathological processes, frequently characteristic of a unique disease or a small subgroup of the URDs. Understanding of both the mechanism of repeat instability and molecular consequen...

  18. Automated Detection of Trinucleotide Repeats in Fragile X Syndrome.

    Science.gov (United States)

    Hamdan; Tynan; Fenwick; Leon

    1997-12-01

    Background: The conventional method for diagnosis of fragile X syndrome has been amplification of the trinucleotide repeat region of the FMR-1 gene by polymerase chain reaction (PCR) and Southern blot analysis to detect full expansion and hypermethylation. "Stuttering" resulting from incomplete amplification is still observed in the PCR products despite the use of reagents that reduce the secondary structure of the GC-rich template. In addition, PCR products can be detected by autoradiography only after 1 to 2 days of exposure. By combination of a recently reported amplification protocol with fluorescence detection of PCR products in an automated DNA sequencer, the PCR protocol for amplification of trinucleotide repeats was simplified. This modified protocol is highly reproducible, more accurate, and less costly than the conventional protocol because of the elimination of radioisotopes from the PCR. Methods and Results: PCRs were conducted with betaine and Pfu DNA polymerase. This improved PCR protocol allowed immediate detection of PCR products in agarose gels containing ethidium bromide. Stuttering was completely eliminated and fragments of up to 1kb ( approximately 250 repeats) were visible in agarose gels. PCR products were automatically detected by laser fluorescence in an automated DNA sequencer by inclusion of a fluorescently-labeled primer in the PCR reaction. A short electrophoresis run of 100 minutes in denaturing acrylamide gels was sufficient to give high resolution of fragments with higher accuracy and sensitivity than conventional detection by autoradiography. Conclusions: A simple, nonradioactive protocol that is more rapid and less expensive than the conventional PCR protocol for the detection of trinucleotide repeats has been developed. By use of this detection protocol, fragment sizes containing up to 100 repeats could be detected, alleles differing by one trinucleotide repeat were clearly resolved, and heterogeneous repeat patterns such as those

  19. Resting metabolic requirements of men and women.

    Science.gov (United States)

    Owen, O E

    1988-05-01

    The resting metabolic rates (RMRs) of 44 lean and obese women, 8 of whom were trained athletes, and of 60 lean and obese men were measured by indirect calorimetry. These healthy humans, ranging from 18 to 82 years old and from 43 to 171 kg in weight, were mentally and physically active. Body composition was determined by densitometry and skinfold thickness. Stepwise multiple regression analysis was used to determine whether one or several variables best predicted RMR. Body compositional variables reflecting active protoplasmic tissue were all highly interrelated. Body weight alone yielded prediction values for RMR comparable to those of other variables of active protoplasmic tissue mass. Among these mentally and physically active women and men, the influence of age on RMR was trivial, and regional distribution of fat had no influence on the RMR. The 95% confidence limits for RMR in both lean and obese subjects were broad. Thus, metabolic efficiency is not necessarily or exclusively related to obesity. In fact, the caloric requirements of humans, based on body weight or active protoplasmic tissue mass, may vary twofold. With the exception of the elderly men, the classic prediction equations and tables developed during the first half of this century greatly overestimated the RMR of healthy lean and obese humans. Therefore, new regression equations for predicting the RMR based on weight and fat-free mass were developed.

  20. Differences in resting EEG related to ability.

    Science.gov (United States)

    Jausovec, N; Jausovec, K

    2000-01-01

    The aim of the present study was to investigate the relationship between different EEG measures (mean power, mean frequency, approximated entropy and coherence), and ability (creativity and intelligence). For that purpose the EEG of 115 student-teachers (Intelligence: M= 115.17; SD = 12.78; IQ(min)= 82; IQ(max)= 136; Creativity - standardized scores: M = 55.97; SD = 10.67; C(min)= 38; C(max)= 84) was recorded while they were resting with eyes open and closed. The study showed only weak correlations between measures based on the level of activity in different areas (mean power, mean frequency and approximated entropy) and creativity. The correlations with IQ scores were even less pronounced. On the other hand, coherence measures showed a much more intense relationship both with creativity as well as with intelligence. In the eyes-open state these differences were mainly distributed over the right hemisphere. The results are discussed in the light of different theories relating brain functioning and ability.

  1. 47 CFR 97.205 - Repeater station.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Repeater station. 97.205 Section 97.205... SERVICE Special Operations § 97.205 Repeater station. (a) Any amateur station licensed to a holder of a Technician, General, Advanced or Amateur Extra Class operator license may be a repeater. A holder of...

  2. 47 CFR 22.1015 - Repeater operation.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Repeater operation. 22.1015 Section 22.1015... Offshore Radiotelephone Service § 22.1015 Repeater operation. Offshore central stations may be used as repeater stations provided that the licensee is able to maintain control of the station, and in...

  3. Rest mutant zebrafish swim erratically and display atypical spatial preferences.

    Science.gov (United States)

    Moravec, Cara E; Li, Edward; Maaswinkel, Hans; Kritzer, Mary F; Weng, Wei; Sirotkin, Howard I

    2015-05-01

    The Rest/Nrsf transcriptional repressor modulates expression of a large set of neural specific genes. Many of these target genes have well characterized roles in nervous system processes including development, plasticity and synaptogenesis. However, the impact of Rest-mediated transcriptional regulation on behavior has been understudied due in part to the embryonic lethality of the mouse knockout. To investigate the requirement for Rest in behavior, we employed the zebrafish rest mutant to explore a range of behaviors in adults and larva. Adult rest mutants of both sexes showed abnormal behaviors in a novel environment including increased vertical swimming, erratic swimming patterns and a proclivity for the tank walls. Adult males also had diminished reproductive success. At 6 days post fertilization (dpf), rest mutant larva were hypoactive, but displayed normal evoked responses to light and sound stimuli. Overall, these results provide evidence that rest dysfunction produces atypical swimming patterns and preferences in adults, and reduced locomotor activity in larvae. This study provides the first behavioral analysis of rest mutants and reveals specific behaviors that are modulated by Rest.

  4. ProtRepeatsDB: a database of amino acid repeats in genomes

    Directory of Open Access Journals (Sweden)

    Chauhan Virander S

    2006-07-01

    Full Text Available Abstract Background Genome wide and cross species comparisons of amino acid repeats is an intriguing problem in biology mainly due to the highly polymorphic nature and diverse functions of amino acid repeats. Innate protein repeats constitute vital functional and structural regions in proteins. Repeats are of great consequence in evolution of proteins, as evident from analysis of repeats in different organisms. In the post genomic era, availability of protein sequences encoded in different genomes provides a unique opportunity to perform large scale comparative studies of amino acid repeats. ProtRepeatsDB http://bioinfo.icgeb.res.in/repeats/ is a relational database of perfect and mismatch repeats, access to which is designed as a resource and collection of tools for detection and cross species comparisons of different types of amino acid repeats. Description ProtRepeatsDB (v1.2 consists of perfect as well as mismatch amino acid repeats in the protein sequences of 141 organisms, the genomes of which are now available. The web interface of ProtRepeatsDB consists of different tools to perform repeat s; based on protein IDs, organism name, repeat sequences, and keywords as in FASTA headers, size, frequency, gene ontology (GO annotation IDs and regular expressions (REGEXP describing repeats. These tools also allow formulation of a variety of simple, complex and logical queries to facilitate mining and large-scale cross-species comparisons of amino acid repeats. In addition to this, the database also contains sequence analysis tools to determine repeats in user input sequences. Conclusion ProtRepeatsDB is a multi-organism database of different types of amino acid repeats present in proteins. It integrates useful tools to perform genome wide queries for rapid screening and identification of amino acid repeats and facilitates comparative and evolutionary studies of the repeats. The database is useful for identification of species or organism specific

  5. Pentatricopeptide repeat proteins in plants.

    Science.gov (United States)

    Barkan, Alice; Small, Ian

    2014-01-01

    Pentatricopeptide repeat (PPR) proteins constitute one of the largest protein families in land plants, with more than 400 members in most species. Over the past decade, much has been learned about the molecular functions of these proteins, where they act in the cell, and what physiological roles they play during plant growth and development. A typical PPR protein is targeted to mitochondria or chloroplasts, binds one or several organellar transcripts, and influences their expression by altering RNA sequence, turnover, processing, or translation. Their combined action has profound effects on organelle biogenesis and function and, consequently, on photosynthesis, respiration, plant development, and environmental responses. Recent breakthroughs in understanding how PPR proteins recognize RNA sequences through modular base-specific contacts will help match proteins to potential binding sites and provide a pathway toward designing synthetic RNA-binding proteins aimed at desired targets.

  6. Two-dimensional quantum repeaters

    Science.gov (United States)

    Wallnöfer, J.; Zwerger, M.; Muschik, C.; Sangouard, N.; Dür, W.

    2016-11-01

    The endeavor to develop quantum networks gave rise to a rapidly developing field with far-reaching applications such as secure communication and the realization of distributed computing tasks. This ultimately calls for the creation of flexible multiuser structures that allow for quantum communication between arbitrary pairs of parties in the network and facilitate also multiuser applications. To address this challenge, we propose a two-dimensional quantum repeater architecture to establish long-distance entanglement shared between multiple communication partners in the presence of channel noise and imperfect local control operations. The scheme is based on the creation of self-similar multiqubit entanglement structures at growing scale, where variants of entanglement swapping and multiparty entanglement purification are combined to create high-fidelity entangled states. We show how such networks can be implemented using trapped ions in cavities.

  7. General benchmarks for quantum repeaters

    CERN Document Server

    Pirandola, Stefano

    2015-01-01

    Using a technique based on quantum teleportation, we simplify the most general adaptive protocols for key distribution, entanglement distillation and quantum communication over a wide class of quantum channels in arbitrary dimension. Thanks to this method, we bound the ultimate rates for secret key generation and quantum communication through single-mode Gaussian channels and several discrete-variable channels. In particular, we derive exact formulas for the two-way assisted capacities of the bosonic quantum-limited amplifier and the dephasing channel in arbitrary dimension, as well as the secret key capacity of the qubit erasure channel. Our results establish the limits of quantum communication with arbitrary systems and set the most general and precise benchmarks for testing quantum repeaters in both discrete- and continuous-variable settings.

  8. Hungarian repeat station survey, 2010

    Directory of Open Access Journals (Sweden)

    Péter Kovács

    2013-03-01

    Full Text Available The last Hungarian repeat station survey was completed between October 2010 and February 2011. Declination, inclination and the total field were observed using one-axial DMI fluxgate magnetometer mounted on Zeiss20A theodolite and GSM 19 Overhauser magnetometer. The magnetic elements of the sites were reduced to the epoch of 2010.5 on the basis of the continuous recordings of Tihany Geophysical Observatory. In stations located far from the reference observatory, the observations were carried out in the morning and afternoon in order to decrease the effect of the distant temporal correction. To further increase the accuracy, on-site dIdD variometer has also been installed near the Aggtelek station, in the Baradla cave, during the survey of the easternmost sites. The paper presents the technical details and the results of our last campaign. The improvement of the accuracy of the temporal reduction by the use of the local variometer is also reported.

  9. Quality control during repeated fryings

    Directory of Open Access Journals (Sweden)

    Cuesta, C.

    1998-08-01

    Full Text Available Most of the debate ¡s about how the slow or frequent turnover of fresh fat affects the deterioration, of fat used in frying. Then, the modification of different oils used in repeated fryings of potatoes without or with turnover of fresh oil, under similar frying conditions, was evaluated by two criteria: by measuring the total polar component isolated by column chromatography and by the evaluation of the specific compounds related to thermoxidative and hydrolytic alteration by High Performance Size Exclusion Chromatography (HPSEC. The results indicate that with frequent turnover of fresh oil, the critical level of 25% of polar material is rarely reached, and there are fewer problems with fat deterioration because the frying tended to increase the level of polar material and thermoxidative compounds (polymers and dimers of triglycerides and oxidized triglycerides in the fryer oil during the first fryings, followed by minor changes and a tendency to reach a near-steady state in successive fryings. However, in repeated frying of potatoes using a null turnover the alteration rate was higher being linear the relationship found between polar material or the different thermoxidative compounds and the number of fryings. On the other hand chemical reactions produced during deep-fat frying can be minimized by using proper oils. In addition the increased level of consumers awareness toward fat composition and its impact on human health could had an impact on the selection of fats for snacks and for industry. In this way monoenic fats are the most adequate from a nutritional point of view and for its oxidative stability during frying.

  10. Comparison of cardiac output determined by different rebreathing methods at rest and at peak exercise.

    Science.gov (United States)

    Jakovljevic, Djordje G; Nunan, David; Donovan, Gay; Hodges, Lynette D; Sandercock, Gavin R H; Brodie, David A

    2008-03-01

    Several rebreathing methods are available for cardiac output (Q (T)) measurement. The aims of this study were threefold: first, to compare values for resting Q (T) produced by the equilibrium-CO(2), exponential-CO(2) and inert gas-N(2)O rebreathing methods and, second, to evaluate the reproducibility of these three methods at rest. The third aim was to assess the agreement between estimates of peak exercise Q (T) derived from the exponential and inert gas rebreathing methods. A total of 18 healthy subjects visited the exercise laboratory on different days. Repeated measures of Q (T), measured in a seated position, were separated by a 5 min rest period. Twelve participants performed an incremental exercise test to determine peak oxygen consumption. Two more exercise tests were used to measure Q (T) at peak exercise using the exponential and inert gas rebreathing methods. The exponential method produced significantly higher estimates at rest (averaging 10.9 l min(-1)) compared with the equilibrium method (averaging 6.6 l min(-1)) and the inert gas rebreathing method (averaging 5.1 l min(-1); P < 0.01). All methods were highly reproducible with the exponential method having the largest coefficient of variation (5.3%). At peak exercise, there were non-significant differences between the exponential and inert gas rebreathing methods (P = 0.14). The limits of agreement were -0.49 to 0.79 l min(-1). Due to the ability to evaluate the degree of gas mixing and to estimate intra-pulmonary shunt, we believe that the inert gas rebreathing method has the potential to measure Q (T) more precisely than either of the CO(2) rebreathing methods used in this study. At peak exercise, the exponential and inert gas rebreathing methods both showed acceptable limits of agreement.

  11. Padre Pio Rest Home, Cappoquin, Waterford.

    LENUS (Irish Health Repository)

    Cooke, J

    2012-01-31

    INTRODUCTION: Orthostatic hypotension (OH) is associated with troublesome symptoms and increased mortality. It is treatable and deserving of accurate diagnosis. This can be time consuming. The current reference standard for its diagnosis is head-up tilt (HUT) testing with continuous beat-to-beat plethysmography. Our objective was to assess the accuracy of sit-stand testing with semi-automatic sphygmomanometry for the diagnosis of OH. DESIGN: Retrospective test of diagnostic accuracy. METHODS: This was a retrospective study performed using a database maintained by a busy syncope unit. HUT testing was performed using an automated tilt table with Finometer monitoring. A 3 min 70 degrees HUT was performed following 5 min supine. Sitting blood pressure (BP) was measured following 3 min rest. Standing BP was measured within 30 s of assuming the upright posture. The results of sit-stand testing were compared with HUT testing as a reference standard. Both tests happened within 5 min of each other and patients underwent no intervention between tests. RESULTS: From a total of 1452 consecutive HUTs, we identified 730 with pre-test measures of sitting and standing BP. The mean age of this group was 70.57 years (SD = 15.1), 62% were female. The sensitivity of sit-stand testing was calculated as 15.5%, specificity as 89.9%, positive predictive value as 61.7%, negative predictive value as 50.2% and the likelihood ratio as 1.6. The area under the Receiver Operator Curve was 0.564. CONCLUSION: We have demonstrated that sit-stand testing for OH has very low diagnostic accuracy. We recommend that the more time-consuming reference standard method of diagnosis be used if the condition is suspected.

  12. Capturing learning effects on eye movements in repeated measures experiments

    DEFF Research Database (Denmark)

    Bagger, Martin; Orquin, Jacob Lund; Fiedler, Susann

    We propose and illustrate that repeated exposure to stimuli sets increases the size of the saccade amplitudes. Saccadic amplitudes are closely related to the perceptual span and therefore used as a measure for the information intake in an experiment. Studies on expertise have shown that experts...... experiment in which 68 participants made choices between four alternatives with three different between subject conditions varying in presentation format (verbal matrix, a pictorial matrix, and a realistic product representation). The results consistently demonstrate an increase of the saccade amplitude over...... the course of the experiment independent of condition. We conclude by discussing our results in the light of the possible increase of the perceptual span and its implications for the research procedure in eye-tracking experiments with a repeated measurement design....

  13. Repeated Witnessing of Conspecifics in Pain: Effects on Emotional Contagion.

    Directory of Open Access Journals (Sweden)

    Maria Carrillo

    Full Text Available Witnessing of conspecifics in pain has been shown to elicit socially triggered freezing in rodents. It is unknown how robust this response is to repeated exposure to a cage-mate experiencing painful stimulation. To address this question, shock-experienced Observer rats repeatedly witnessed familiar Demonstrators receive painful footshocks (six sessions. Results confirm that Observers freeze during the first testing session. The occurrence of this behaviour however gradually diminished as the experimental sessions progressed, reaching minimal freezing levels by the end of the experiments. In contrast, the appearance and continuous increase in the frequency of yawning, a behavior that was inhibited by metyrapone (i.e,. a glucocorticoid synthesis blocker, might represent an alternative coping strategy, suggesting that the observer's reduced freezing does not necessarily indicate a disappearance in the affective response to the Demonstrator's distress.

  14. REST is up-regulated by epidermal growth factor in HeLa cells and inhibits apoptosis by influencing histone H3 acetylation.

    Science.gov (United States)

    Baiula, Monica; Carbonari, Gioia; Dattoli, Samantha D; Calienni, Maria; Bedini, Andrea; Spampinato, Santi

    2012-08-01

    REST (repressor element 1-silencing transcription factor) is a transcription factor that recruits histone deacetylases to silence gene transcription. REST appears to play a paradoxical role in cancer cells: it exhibits tumor suppressor activity or promotes tumorigenesis, depending upon the setting. The extracellular signaling molecules that control REST gene expression in cancer cells remain poorly understood. In this study, we report that REST expression in HeLa cells is elevated in cells exposed to epidermal growth factor or serum, whereas the rate of cell apoptosis is low. Apoptosis induced by serum withdrawal is significantly increased in HeLa cells treated with an antisense phosphorothioate oligodeoxynucleotide (AS ODN) capable of down-regulating REST expression, whereas in HeLa cells transfected with a REST expressing plasmid, REST overexpression reduces the marked apoptosis caused, in absence of serum, by exposure to an anti-Fas receptor antibody imitating the Fas ligand activity plus PD 98059, a blocker of extracellular signal-regulated kinase 1/2 activation. REST knockdown also reduces mRNA levels of the antiapoptotic protein Bcl-X(L) whereas in HeLa cells overexpressing REST, the reduction of Bcl-X(L) mRNA caused by the anti-Fas receptor antibody plus PD 98059 is significantly decreased. Finally, we report that acetylation of histone H3 is increased in HeLa cells exposed to AS ODN or anti-Fas receptor antibody, whereas it is reduced in cells transfected with the REST expressing plasmid. Our findings indicate that REST is a novel gene regulated by EGF in HeLa cells that potentially contributes to the modulation of apoptosis via epigenetic mechanisms.

  15. Physiological responses of women to simulated weightlessness: A review of the first female bed-rest study

    Science.gov (United States)

    Sandler, H.; Winter, D. L.

    1978-01-01

    Subjects were exposed to centrifugation, to lower body negative pressure (LBNP), and to exericse stress both before and after bed rest. Areas studied were centrifugation tolerance, fluid electrolyte changes and hematology, tolerance to LBNP, physical working capacity, biochemistries, blood fibrinolytic activity, female metabolic and hormonal responses, circadian alterations, and gynecology. Results were compared with the responses observed in similarly bed-rested male subjects. The bed-rested females showed deconditioning responses similar to those of the males, although with some differences. Results indicate that women are capable of coping with exposure to weightlessness and, moreover, that they may be more sensitive subjects for evaluating countermeasures to weightlessness and developing criteria for assessing applicants for shuttle voyages.

  16. A REST-ful interpretation for embedded modular systems based on open architecture

    Science.gov (United States)

    Lyke, James

    2016-05-01

    The much-anticipated revolution of the "Internet of things" (IoT) is expected to generate one trillion internet devices within the next 15 years, mostly in the form of simple wireless sensor devices. While this revolution promises to transform silicon markets and drive a number of disruptive changes in society, it is also the case that the protocols, complexity, and security issues of extremely large dynamic, co-mingled networks is still poorly understood. Furthermore, embedded system developers, to include military and aerospace users, have largely ignored the potential (good and bound) of the cloudlike, possibly intermingling networks having variable structure to how future systems might be engineered. In this paper, we consider a new interpretation of IoT inspired modular architecture strategies involving the representational state transfer (REST) model, in which dynamic networks with variable structure employ stateless application programming interface (API) concepts. The power of the method, which extends concepts originally developed for space plug-and-play avionics, is that it allows for the fluid co-mingling of hardware and software in networks whose structure can overlap and evolve. Paradoxically, these systems may have the most stringent determinism and fault-tolerant needs. In this paper we review how RESTful APIs can potentially be used to design, create, test, and deploy systems rapidly while addressing security and referential integrity even when the nodes of many systems might physically co-mingle. We will also explore ways to take advantage of the RESTful paradigm for fault tolerance and what extensions might be necessary to deal with high-performance and determinism.

  17. The clinical utility of vocal dosimetry for assessing voice rest.

    Science.gov (United States)

    Misono, Stephanie; Banks, Kathryn; Gaillard, Philippe; Goding, George S; Yueh, Bevan

    2015-01-01

    Voice rest is frequently recommended following surgical disruption of vocal fold epithelium, but patients report variable adherence to voice rest recommendations. The objective of this study was to assess the clinical utility of an ambulatory vocal dosimeter for measuring adherence to voice rest recommendations. Outcomes research. Part 1: To determine the utility of the dosimeter in nonclinical use, the relationship between self-reported voice use and dosimeter measurements was examined in normal subjects (n = 11) who prospectively logged voice use while wearing the dosimeter. Part 2: To determine clinical utility of the dosimeter, patients undergoing vocal fold surgery for which postoperative voice rest was recommended (n = 11) wore a dosimeter for 2 days prior to and 2 days after surgery. Phonation percent and sound level were compared at baseline and during voice rest. The dosimeter performed as hypothesized with both normal subjects and patients. A moderate correlation (r = 0.62) was noted between self-reported voice use and dosimeter measurements in normal subjects. In patients on voice rest, a statistically and clinically significant decrease was observed in measured voice use, both in phonation time (P = .002) and intensity of phonation (P = .004). Ambulatory vocal dosimetry may have clinical utility for assessing adherence to voice rest recommendations. This information will be useful for the design of future studies on voice rest. © 2014 The American Laryngological, Rhinological and Otological Society, Inc.

  18. Voice rest after vocal fold surgery: current practice and evidence.

    Science.gov (United States)

    Coombs, A C; Carswell, A J; Tierney, P A

    2013-08-01

    Voice rest is commonly recommended after vocal fold surgery, but there is a lack of evidence base and no standard protocol. The aim of this study was to establish common practice regarding voice rest following vocal fold surgery. An online survey was circulated via e-mail invitation to members of the ENT UK Expert Panel between October and November 2011. The survey revealed that 86.5 per cent of respondents agreed that 'complete voice rest' means no sound production at all, but there was variability in how 'relative voice rest' was defined. There was no dominant type of voice rest routinely recommended after surgery for laryngeal papillomatosis or intermediate pathologies. There was considerable variability in the duration of voice rest recommended, with no statistically significant, most popular response (except for malignant lesions). Surgeons with less than 10 years of experience were more likely to recommend fewer days of voice rest. There is a lack of consistency in advice given to patients after vocal fold surgery, in terms of both type and length of voice rest. This may arise from an absence of robust evidence on which to base practice.

  19. Atypical Laterality of Resting Gamma Oscillations in Autism Spectrum Disorders

    Science.gov (United States)

    Maxwell, Christina R.; Villalobos, Michele E.; Schultz, Robert T.; Herpertz-Dahlmann, Beate; Konrad, Kerstin; Kohls, Gregor

    2015-01-01

    Abnormal brain oscillatory activity has been found in autism spectrum disorders (ASD) and proposed as a potential biomarker. While several studies have investigated gamma oscillations in ASD, none have examined resting gamma power across multiple brain regions. This study investigated resting gamma power using EEG in 15 boys with ASD and 18 age…

  20. 75 FR 55851 - Flightcrew Member Duty and Rest Requirements

    Science.gov (United States)

    2010-09-14

    ... proposal recognizes the growing similarities between the types of operations and the universality of.... Pre-Flight Duty Period Rest 2. Cumulative Rest Requirements L. Fatigue Risk Management Systems M... extensive certificate holder management, direct operational experience, or both. \\6\\ See...

  1. Atypical Laterality of Resting Gamma Oscillations in Autism Spectrum Disorders

    Science.gov (United States)

    Maxwell, Christina R.; Villalobos, Michele E.; Schultz, Robert T.; Herpertz-Dahlmann, Beate; Konrad, Kerstin; Kohls, Gregor

    2015-01-01

    Abnormal brain oscillatory activity has been found in autism spectrum disorders (ASD) and proposed as a potential biomarker. While several studies have investigated gamma oscillations in ASD, none have examined resting gamma power across multiple brain regions. This study investigated resting gamma power using EEG in 15 boys with ASD and 18 age…

  2. Restful Implementation of Catalogue Service for Geospatial Data Provenance

    Science.gov (United States)

    Jiang, L. C.; Yue, P.; Lu, X. C.

    2013-10-01

    Provenance, also known as lineage, is important in understanding the derivation history of data products. Geospatial data provenance helps data consumers to evaluate the quality and reliability of geospatial data. In a service-oriented environment, where data are often consumed or produced by distributed services, provenance could be managed by following the same service-oriented paradigm. The Open Geospatial Consortium (OGC) Catalogue Service for the Web (CSW) is used for the registration and query of geospatial data provenance by extending ebXML Registry Information Model (ebRIM). Recent advance of the REpresentational State Transfer (REST) paradigm has shown great promise for the easy integration of distributed resources. RESTful Web Service aims to provide a standard way for Web clients to communicate with servers based on REST principles. The existing approach for provenance catalogue service could be improved by adopting the RESTful design. This paper presents the design and implementation of a catalogue service for geospatial data provenance following RESTful architecture style. A middleware named REST Converter is added on the top of the legacy catalogue service to support a RESTful style interface. The REST Converter is composed of a resource request dispatcher and six resource handlers. A prototype service is developed to demonstrate the applicability of the approach.

  3. REST regulates oncogenic properties of glioblastoma stem cells

    Science.gov (United States)

    Kamal, Mohamed M.; Sathyan, Pratheesh; Singh, Sanjay K.; Zinn, Pascal O.; Marisetty, Anantha L.; Liang, Shoudan; Gumin, Joy; El-Mesallamy, Hala Osman; Suki, Dima; Colman, Howard; Fuller, Gregory N.; Lang, Frederick F.; Majumder, Sadhan

    2013-01-01

    Glioblastoma multiforme (GBM) tumors are the most common malignant primary brain tumors in adults. Although many GBM tumors are believed to be caused by self-renewing, glioblastoma-derived stem-like cells (GSCs), the mechanisms that regulate self-renewal and other oncogenic properties of GSCs are only now being unraveled. Here we showed that GSCs derived from GBM patient specimens express varying levels of the transcriptional repressor REST, suggesting heterogeneity across different GSC lines. Loss- and gain-of-function experiments indicated that REST maintains self-renewal of GSCs. High REST-expressing GSCs (HR-GSCs) produced tumors histopathologically distinct from those generated by low REST-expressing GSCs (LR-GSCs) in orthotopic mouse brain tumor models. Knockdown of REST in HR-GSCs resulted in increased survival in GSC-transplanted mice and produced tumors with higher apoptotic and lower invasive properties. Conversely, forced expression of exogenous REST in LR-GSCs produced decreased survival in mice and produced tumors with lower apoptotic and higher invasive properties, similar to HR-GSCs. Thus, based on our results, we propose that a novel function of REST is to maintain self-renewal and other oncogenic properties of GSCs and that REST can play a major role in mediating tumorigenicity in GBM. PMID:22228704

  4. Wrist dermatitis: contact allergy to neoprene in a keyboard wrist rest.

    Science.gov (United States)

    Johnson, R C; Elston, D M

    1997-09-01

    A case of allergic contact dermatitis to a keyboard wrist rest containing neoprene is reported. The patient, who had a history of sensitivity to rubber products, developed an acute vesicular reaction of the palmar aspects of her distal wrists, followed by eczematous patches of her extremities and face. Treatment with prednisone, a 3-week tapering dose (60, 40, 20 mg), cleared the dermatitis. The widespread uses of neoprene are discussed and suggest that neoprene will become a common source of contact dermatitis as the potential sources of exposure increase.

  5. Vitamin D: Findings from Antarctic, Bed Rest, Houston, and ISS

    Science.gov (United States)

    Zwart, Sara R.; Locke, J.; Pierson, D.; Mehta, S.; Bourbeau, Y.; Parsons, H.; Smith, S. M.

    2009-01-01

    Obtaining vitamin D is critical for space travelers because they lack ultraviolet light exposure and have an insufficient dietary supply of vitamin D. Despite the provision of 400 IU vitamin D supplements to International Space Station (ISS) early crewmembers, vitamin D status was consistently lower after flight than before flight, and in several crewmembers has decreased to levels considered clinically significant. Vitamin D has long been known to play a role in calcium metabolism, and more recently its non-calcitropic functions have been recognized. According to the results of several recent studies, functionally relevant measures indicate that the lower limit of serum 25-hydroxyvitamin D (a marker of vitamin D status) should be raised from the current 23 nmol/L to 80 nmol/L. The mean preflight serum 25-hydroxyvitamin D (25-OH vit D) for U.S. ISS crewmembers to date is 63 +/- 16 nmol/L, and after a 4- to 6-mo space flight it typically decreases 25-30% despite supplementation (400 IU/d). The sub-optimal pre- and postflight vitamin D status is an issue that needs to be addressed, to allow NASA to better define the appropriate amount of supplemental vitamin D to serve as a countermeasure against vitamin D deficiency in astronaut crews. A series of ground-based and flight studies in multiple models have been conducted, including Antarctica in winter months when UV-B radiation levels are essentially zero, bed rest where subjects are not exposed to UV-B radiation for 60-90 days, in free-living individuals in Houston, and in International Space Station crewmembers. In these studies, we looked at dose regimen and efficacy, compliance issues, as well as toxicity. Preliminary results from these studies will be presented. Together, the data from these studies will enable us to provide space crews with evidence-based recommendations for vitamin D supplementation. The findings also have implications for other persons with limited UV light exposure, including polar workers and

  6. OPTIMAL WORK-REST SCHEDULE FOR COMPUTER USERS

    Directory of Open Access Journals (Sweden)

    Mervat Abdelrahman Mohamed

    2017-04-01

    Full Text Available Background: Musculoskeletal disorders are the most common health problems for computer users who work for an extended period. The aim of this study was to identify the best work-rest schedule with the three different work-rest groups: no rest break, mid-rest break, and multiple- rest breaks, which was associated with the least EMG activities of the upper trapezius muscle and would be beneficial for musculoskeletal health. Methods: Forty-five right-handed females complaining of neck discomfort were randomly assigned into three equal groups, Group1 (no rest break they were be engaged in sixty minutes of typing followed by ten minutes break (60-10, group 2 (mid-rest break thirty minutes of typing followed by five minutes break (30-5, and group 3 (multiple rest breaks fifteen minutes of typing followed by 2.5 minutes break (15-2.5. Surface EMG was used to pick up the electrical activity of right and left upper trapezius throughout the computer typing task. Results: There was a statistically significant reduction of normalized RMS (p<0.05 between the three groups for both right and left upper trapezius. Also, our results demonstrated a positive effect of mid and multiple rest breaks regarding reduced muscle activity in the upper trapezius muscle during a computer work. Conclusion: There is a positive effect of mid and multiple rest breaks regarding reduced muscle activity in the upper trapezius muscle throughout a computer work in subjects with neck and shoulder discomfort.

  7. Resting autonomic modulations and the heart rate response to exercise.

    Science.gov (United States)

    Nunan, David; Jakovljevic, Djordje G; Donovan, Gay; Singleton, Lynette D; Sandercock, Gavin R H; Brodie, David A

    2010-08-01

    Identify the underlying role of resting heart rate variability (HRV) in the hearts response to graded exercise testing (GXT). Resting 5-min HRV and heart rate (HR) measurements were made in 33 volunteers (19 males, median age 34, range 25-63 years and 14 females median age 48, range 21-63 years). Measures of VO2 peak and HR obtained during a maximal GXT and heart rate recovery (HRR) post-GXT were assessed for associations with resting HRV. Differences and effect size (d) for measures of HRV were assessed between groups based on established risk cut-points for resting, exercise and recovery HR responses. Small associations were observed for the majority of resting HRV and GXT HR responses (best r value = -0.27, P > 0.05). Measures of HRV demonstrated moderate associations with HRR (best r value = 0.46, P < 0.05) and were able to predict a negative risk HRR. In contrast to other dependent variables, measures of HRV were consistently able to demonstrate significant and moderate to large (d = 0.9-2.0) differences between groups based on literature defined prognostic HR cut-points. Small associations with HR responses to exercise prevent their accurate prediction from resting HRV. Data support the use of vagally mediated resting HRV in predicting better HRR. Lower resting autonomic modulations underlined high risk resting and exercise HR responses. Resting short-term HRV measurements should be considered when assessing cardiac autonomic health from the HR response before, during and/or after exercise.

  8. The effect of exercise training on left ventricular relaxation and diastolic suction at rest and during orthostatic stress after bed rest.

    Science.gov (United States)

    Carrick-Ranson, Graeme; Hastings, Jeffrey L; Bhella, Paul S; Shibata, Shigeki; Levine, Benjamin D

    2013-02-0