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Sample records for antidepressive-drug-induced bodyweight gain

  1. Unaltered instrumental learning and attenuated body-weight gain in rats during non-rotating simulated shiftwork.

    PubMed

    Leenaars, C H C; Kalsbeek, A; Hanegraaf, M A J; Foppen, E; Joosten, R N J M A; Post, G; Dematteis, M; Feenstra, M G P; van Someren, E J W

    2012-04-01

    Exposure to shiftwork has been associated with multiple health disorders and cognitive impairments in humans. We tested if we could replicate metabolic and cognitive consequences of shiftwork, as reported in humans, in a rat model comparable to 5 wks of non-rotating night shifts. The following hypotheses were addressed: (i) shiftwork enhances body-weight gain, which would indicate metabolic effects; and (ii) shiftwork negatively affects learning of a simple goal-directed behavior, i.e., the association of lever pressing with food reward (instrumental learning), which would indicate cognitive effects. We used a novel method of forced locomotion to model work during the animals' normal resting period. We first show that Wistar rats, indeed, are active throughout a shiftwork protocol. In contrast with previous findings, the shiftwork protocol attenuated the normal weight gain to 76 ± 8 g in 5 wks as compared to 123 ± 15 g in the control group. The discrepancy with previous work may be explained by the concurrent observation that with our shiftwork protocol rats did not adjust their between-work circadian activity pattern. They maintained a normal level of activity during the "off-work" periods. In the control experiment, rats were kept active during the dark period, normally dominated by activity. This demonstrated that forced activity, per se, did not affect body-weight gain (mean ± SEM: 85 ± 11 g over 5 wks as compared to 84 ± 11 g in the control group). Rats were trained on an instrumental learning paradigm during the fifth week of the protocol. All groups showed equivalent increases in lever pressing from the first (3.8 ± .7) to the sixth (21.3 ± 2.4) session, and needed a similar amount of sessions (5.1 ± .3) to reach a learning criterion (≥ 27 out of 30 lever presses). These results suggest that while on prolonged non-rotating shiftwork, not fully reversing the circadian rhythm might actually be beneficial to prevent body-weight gain and cognitive

  2. Association study of NRXN3 polymorphisms with schizophrenia and risperidone-induced bodyweight gain in Chinese Han population.

    PubMed

    Hu, Xiaofeng; Zhang, Jishui; Jin, Chao; Mi, Weifeng; Wang, Fang; Ma, Wenbin; Ma, Cuicui; Yang, Yongfeng; Li, Wenqiang; Zhang, Hongxing; Du, Bo; Li, Keqing; Liu, Chenxing; Wang, Lifang; Lu, Tianlan; Zhang, Hongyan; Lv, Luxian; Zhang, Dai; Yue, Weihua

    2013-06-03

    Recent researches have implicated that mutations in the neurexin-3 (NRXN3) gene on chromosome 14q24.3-q31.1 might play a role in addiction, autism, and obesity. In order to explore the association of NRXN3 polymorphisms with schizophrenia, we examined seven single nucleotide polymorphisms (SNPs) in NRXN3 spanning 1.33 Mb of this gene, in a Chinese Han sample of 1214 schizophrenic patients and 1517 healthy control subjects. Our results showed that three SNPs were associated with schizophrenia (rs7157669: A>C, p=0.006; rs724373: C>T, p=0.014; rs7154021: C>T, p=0.018). After being corrected for multiple tests, the association of rs7157669 remained significant but those for two others were modest. According to the linkage disequilibrium pattern, the 7 SNPs may construct 3 haplotype blocks. Several haplotypes were significantly associated with schizophrenia, constructed by rs11624704-rs7157669-rs724373 (AAC, p=0.003; ACT, p=0.007, both remained significant after permutation tests), rs7154021-rs7142344 (TT, p=0.024; CT, p=0.012), respectively. Among the patients, 326 ones at first onset have received 6-week monotherapy of risperidone. Further analyses showed that two SNPs were associated with percentage of bodyweight gain following a 6-week therapy of risperidone (rs11624704: p=0.03; rs7154021: p=0.008) and rs7154021 remained significant after permutation test. Our findings suggested that NRXN3 might represent a major susceptibility gene for schizophrenia and have a role in bodyweight gain related to therapy of risperidone in Chinese Han population.

  3. The effects of different levels of peppermint alcoholic extract on body-weight gain and blood biochemical parameters of adult male Wistar rats

    PubMed Central

    Mesbahzadeh, Behzad; Akbari, Mohsen; kor, Nasroallah Moradi; Zadeh, Jalal Bayati

    2015-01-01

    Introduction Peppermint is an efficient medicinal plant for the treatment of diseases, and it also can be used to produce raw materials in the pharmaceutical industry. The purpose of the current study was to evaluate the effects of various levels of peppermint alcoholic extract on body-weight gain and blood biochemical parameters in adult male Wistar rats. Methods This experiment was conducted using a completely randomized design (CRD). Fifty adult, healthy, male Wistar rats (ages of 2.5–3 months; weights of 190–210 g) were allocated randomly into five groups. T1 was the control group in which the rats received 0.3 ml of distilled water). Groups T2, T3, T4, and T5 received 75, 150, 300, and 600 mg/kg of peppermint extract, respectively. The rats received daily pretreatment by oral gavages for 21 days. We recorded body weights at the beginning and at the end of the study to determine the changes in the body weights. Blood samples were collected for the measurement of glucose, cholesterol, triglycerides, HDL, LDL, albumin, globulin, and total protein. Statistical analysis of the data was done by SAS software. The data statistically analyzed using one-way analysis of variance (ANOVA), which was conducted through Dennett’s multiple comparison post-test. Results The results indicated that the rats treated with peppermint gained more weight (p < 0.05) and also decreased the serum concentrations of triglycerides, total cholesterol, LDL, and glucose in T3, T4 and T5 than the other groups (p < 0.05). Conclusion Peppermint extract had a positive effect on body-weight gain and some blood parameters in adult male Wistar rats. The findings showed that peppermint is a crucial substance at high temperature, and future research should be focused on determining the details of the mechanisms involved in producing the observed effects of peppermint extract. PMID:26516445

  4. Pharmacological management of atypical antipsychotic-induced weight gain.

    PubMed

    Baptista, Trino; ElFakih, Yamily; Uzcátegui, Euderruh; Sandia, Ignacio; Tálamo, Eduardo; Araujo de Baptista, Enma; Beaulieu, Serge

    2008-01-01

    Excessive bodyweight gain was reported during the 1950s as an adverse effect of typical antipsychotic drug treatment, but the magnitude of bodyweight gain was found to be higher with the atypical antipsychotic drugs that were introduced after 1990. Clozapine and olanzapine produce the greatest bodyweight gain, ziprasidone and aripiprazole have a neutral influence, and quetiapine and risperidone cause an intermediate effect. In the CATIE study, the percentage of patients with bodyweight gain of >7% compared with baseline differed significantly between the antipsychotic drugs, i.e. 30%, 16%, 14%, 12% and 7% for olanzapine, quetiapine, risperidone, perphenazine (a typical antipsychotic) and ziprasidone, respectively (p<0.001). Appetite stimulation is probably a key cause of bodyweight gain, but genetic polymorphisms modify the bodyweight response during treatment with atypical antipsychotics. In addition to nutritional advice, programmed physical activity, cognitive-behavioural training and atypical antipsychotic switching, pharmacological adjunctive treatments have been assessed to counteract excessive bodyweight gain. In some clinical trials, nizatidine, amantadine, reboxetine, topiramate, sibutramine and metformin proved effective in preventing or reversing atypical antipsychotic-induced bodyweight gain; however, the results are inconclusive since few randomized, placebo-controlled clinical trials have been conducted. Indeed, most studies were short-term trials without adequate statistical power and, in the case of metformin, nizatidine and sibutramine, the results are contradictory. The tolerability profile of these agents is adequate. More studies are needed before formal recommendations on the use of these drugs can be made. Meanwhile, clinicians are advised to use any of these adjunctive treatments according to their individual pharmacological and tolerability profiles, and the patient's personal and family history of bodyweight gain and metabolic dysfunction.

  5. Parental perception of child bodyweight and health among Mexican-American children with acanthosis nigricans.

    PubMed

    Su, Dejun; Huang, Terry T-K; Anthony, Renaisa; Ramos, Athena; Toure, Drissa; Wang, Hongmei

    2014-10-01

    Acanthosis nigricans (AN) is a cutaneous marker associated with elevated risk of type 2 diabetes. This study assesses mother-father differences in perception of child's bodyweight and health by Mexican-American parents with AN-positive children. The study used medical records in conjunction with survey data collected between 2011 and 2012 for 309 Mexican-American children with AN in South Texas. Multivariate logit models were estimated to assess mother-father differences in perception of child bodyweight and health controlling for selected child- and parent-level covariates. About 91 % of the children in the sample were obese and 6.5 % were overweight. One fifth of mothers and 38.5 % of fathers in the sample expressed no concern of their children's bodyweight. After adjusting for selected explanatory variables at both the child and parent level, the odds for fathers, relative to mothers, to be concerned about child's bodyweight were 82 % lower (OR = 0.18, p < 0.05). Similar findings also hold for parental awareness of child's AN (OR = 0.19, p < 0.05). Among Mexican-American families with AN-positive children, the lack of concern over child's bodyweight, unawareness of AN, and misconception of child's health on the part of many parents, especially of fathers, constitutes a challenge to diabetes prevention. Health education programs targeting Mexican-American families with AN-positive children might be more cost effective to consider mother-father differences in perception of child health and bodyweight.

  6. Orthotic Body-Weight Support Through Underactuated Potential Energy Shaping with Contact Constraints.

    PubMed

    Lv, Ge; Gregg, Robert D

    2015-12-01

    Body-weight support is an effective clinical tool for gait rehabilitation after neurological impairment. Body-weight supported training systems have been developed to help patients regain mobility and confidence during walking, but conventional systems constrain the patient's treatment in clinical environments. We propose that this challenge could be addressed by virtually providing patients with body-weight support through the actuators of a powered orthosis (or exoskeleton) utilizing potential energy shaping control. However, the changing contact conditions and degrees of underactuation encountered during human walking present significant challenges to consistently matching a desired potential energy for the human in closed loop. We therefore introduce a generalized matching condition for shaping Lagrangian systems with holonomic contact constraints. By satisfying this matching condition for four phases of gait, we derive control laws to achieve virtual body-weight support through a powered knee-ankle orthosis. We demonstrate beneficial effects of virtual body-weight support in simulations of a human-like biped model, indicating the potential clinical value of this proposed control approach.

  7. Orthotic Body-Weight Support Through Underactuated Potential Energy Shaping with Contact Constraints

    PubMed Central

    Lv, Ge; Gregg, Robert D.

    2015-01-01

    Body-weight support is an effective clinical tool for gait rehabilitation after neurological impairment. Body-weight supported training systems have been developed to help patients regain mobility and confidence during walking, but conventional systems constrain the patient's treatment in clinical environments. We propose that this challenge could be addressed by virtually providing patients with body-weight support through the actuators of a powered orthosis (or exoskeleton) utilizing potential energy shaping control. However, the changing contact conditions and degrees of underactuation encountered during human walking present significant challenges to consistently matching a desired potential energy for the human in closed loop. We therefore introduce a generalized matching condition for shaping Lagrangian systems with holonomic contact constraints. By satisfying this matching condition for four phases of gait, we derive control laws to achieve virtual body-weight support through a powered knee-ankle orthosis. We demonstrate beneficial effects of virtual body-weight support in simulations of a human-like biped model, indicating the potential clinical value of this proposed control approach. PMID:26900254

  8. Dog behavior co-varies with height, bodyweight and skull shape.

    PubMed

    McGreevy, Paul D; Georgevsky, Dana; Carrasco, Johanna; Valenzuela, Michael; Duffy, Deborah L; Serpell, James A

    2013-01-01

    Dogs offer unique opportunities to study correlations between morphology and behavior because skull shapes and body shape are so diverse among breeds. Several studies have shown relationships between canine cephalic index (CI: the ratio of skull width to skull length) and neural architecture. Data on the CI of adult, show-quality dogs (six males and six females) were sourced in Australia along with existing data on the breeds' height, bodyweight and related to data on 36 behavioral traits of companion dogs (n = 8,301) of various common breeds (n = 49) collected internationally using the Canine Behavioral Assessment and Research Questionnaire (C-BARQ). Stepwise backward elimination regressions revealed that, across the breeds, 33 behavioral traits all but one of which are undesirable in companion animals correlated with either height alone (n = 14), bodyweight alone (n = 5), CI alone (n = 3), bodyweight-and-skull shape combined (n = 2), height-and-skull shape combined (n = 3) or height-and-bodyweight combined (n = 6). For example, breed average height showed strongly significant inverse relationships (p<0.001) with mounting persons or objects, touch sensitivity, urination when left alone, dog-directed fear, separation-related problems, non-social fear, defecation when left alone, owner-directed aggression, begging for food, urine marking and attachment/attention-seeking, while bodyweight showed strongly significant inverse relationships (p<0.001) with excitability and being reported as hyperactive. Apart from trainability, all regression coefficients with height were negative indicating that, across the breeds, behavior becomes more problematic as height decreases. Allogrooming increased strongly (p<0.001) with CI and inversely with height. CI alone showed a strong significant positive relationship with self-grooming (p<0.001) but a negative relationship with chasing (p = 0.020). The current study demonstrates how aspects of CI (and therefore brain shape

  9. Kinematic assessment of treadmill running using different body-weight support harnesses.

    PubMed

    Millslagle, Duane; Levy, Morris; Matack, Nicholas

    2006-10-01

    10 male collegiate runners (M age = 21.4, SD = 1.5 yr.) ran on a treadmill with no body-weight support (BWS), 20% BWS, and 40% BWS conditions. In addition, they wore three different commercially available harnesses at the 20% and 40% BWS conditions. The aim was to run on the treadmill at a fast speed while maintaining an adequate step length. The purpose was to investigate how each harness changed running gait, and the differences in running gait between the harnesses with various body-weight support. Analysis of variance indicated significant restriction of upper body torso rotation between the harnesses at the 40% BWS conditions. Body-weight support resulted in a longer stride, decreased cadence, less vertical displacement of the center of mass, and diminished hip and ankle joint excursions. These changes indicated that increased body-weight support results in longer steps with the foot contacting the belt for a shorter period of time with less leg angular changes throughout the running cycling.

  10. Treadmill Training with Partial Body-Weight Support in Children with Cerebral Palsy: A Systematic Review

    ERIC Educational Resources Information Center

    Mutlu, Akmer; Krosschell, Kristin; Spira, Deborah Gaebler

    2009-01-01

    OKAim: The aim of this systematic review was to examine the literature on the effects of partial body-weight support treadmill training (PBWSTT) in children with cerebral palsy (CP) on functional outcomes and attainment of ambulation. Method: We searched the relevant literature from 1950 to July 2007. We found eight studies on the use of PWSBTT on…

  11. Nutraceuticals for body-weight management: The role of green tea catechins.

    PubMed

    Janssens, Pilou L H R; Hursel, Rick; Westerterp-Plantenga, Margriet S

    2016-08-01

    Green tea catechins mixed with caffeine have been proposed as adjuvants for maintaining or enhancing energy expenditure and for increasing fat oxidation, in the context of prevention and treatment of obesity. These catechins-caffeine mixtures seem to counteract the decrease in metabolic rate that occurs during weight loss. Their effects are of particular importance during weight maintenance after weight loss. Other metabolic targets may be fat absorption and the gut microbiota composition, but these effects still need further investigation in combination with weight loss. Limitations for the effects of green tea catechins are moderating factors such as genetic predisposition related to COMT-activity, habitual caffeine intake, and ingestion combined with dietary protein. In conclusion, a mixture of green tea catechins and caffeine has a beneficial effect on body-weight management, especially by sustained energy expenditure, fat oxidation, and preservation of fat free body-mass, after energy restriction induced body-weight loss, when taking the limitations into account.

  12. Management of atypical antipsychotic-induced weight gain in schizophrenic patients with topiramate.

    PubMed

    Lin, Yi-Hsiung; Liu, Chia-Yih; Hsiao, Mei-Chun

    2005-10-01

    Patients treated with atypical antipsychotic drugs commonly gain excess weight. Because obesity is associated with considerable morbidity and decreased life expectancy, treatment of weight gain in these patients is critical. Topiramate, a fairly new anticonvulsant, promotes bodyweight loss in healthy obese subjects, patients with bipolar disorder, and patients with eating disorder. However, there are very few reports about the efficacy of topiramate for weight management in schizophrenic patients. We present the cases of three Taiwanese patients with schizophrenia whose bodyweight increased as a result of atypical antipsychotics treatment, then was controlled by topiramate without aggravation of their psychotic symptoms.

  13. Cognitive Fatigue Influences Time-On-Task during Bodyweight Resistance Training Exercise

    PubMed Central

    Head, James R.; Tenan, Matthew S.; Tweedell, Andrew J.; Price, Thomas F.; LaFiandra, Michael E.; Helton, William S.

    2016-01-01

    Prior investigations have shown measurable performance impairments on continuous physical performance tasks when preceded by a cognitively fatiguing task. However, the effect of cognitive fatigue on bodyweight resistance training exercise task performance is unknown. In the current investigation 18 amateur athletes completed a full body exercise task preceded by either a cognitive fatiguing or control intervention. In a randomized repeated measure design, each participant completed the same exercise task preceded by a 52 min cognitively fatiguing intervention (vigilance) or control intervention (video). Data collection sessions were separated by 1 week. Participants rated the fatigue intervention with a significantly higher workload compared to the control intervention (p < 0.001). Additionally, participants self-reported significantly greater energetic arousal for cognitively fatiguing task (p = 0.02). Cognitive fatigue did not significantly impact number of repetitions completed during the exercise task (p = 0.77); however, when cognitively fatigued, participants had decreased percent time-on-task (57%) relative to the no fatigue condition (60%; p = 0.04). RPE significantly changed over time (p < 0.001), but failed to show significant differences between the cognitive fatigue intervention and control intervention (p > 0.05). There was no statistical difference for heart rate or metabolic expenditure as a function of fatigue intervention during exercise. Cognitively fatigued athletes have decreased time-on-task in bodyweight resistance training exercise tasks. PMID:27635122

  14. The effects of two different arm positions and weight status on select kinematic variables during the bodyweight squat.

    PubMed

    Glave, A Page; Olson, Jacilyn M; Applegate, Danika K; Brezzo, Ro Di

    2012-11-01

    The bodyweight squat is a common movement and is safe and effective. There are many variations and techniques, but little research has explored alterations of the movement. The purpose of this study was to examine the effects of 2 arm positions on select kinematic variables during the bodyweight squat. The participants were classified as normal-weight (NW: n = 17, height: 1.67 ± 0.06 m, weight: 61.25 ± 6.90 kg, body mass index [BMI]: 21.92 ± 1.68) or overweight (OW: n = 11, height: 1.68 ± 0.06 m, weight: 88.91 ± 16.86 kg, BMI: 31.64 ± 6.06) according to BMI. The participants completed a bodyweight squat with the arms held at the sides (AP1) followed by a bodyweight squat with the arms held at shoulder level (AP2). Reflective markers were placed on the shoulder, hip, knee, base of the fifth toe, and heel. Data were recorded and analyzed using Peak 9. Trunk and knee flexion was analyzed using separate repeated measures analyses of variance. Overweight participants exhibited reduced knee (OW: 75.56 ± 17.94°; NW: 83.73 ± 13.03°; p < 0.05) and trunk flexion (OW: -78.18 ± 17.72°; NW: -90.65 ± 17.57°; p = 0.05). Holding the arms at shoulder level resulted in greater knee flexion (AP1: 80.81 ± 15.17°; AP2: 86.31 ± 15.21°; p < 0.01). Both weight status and arm position affected the range of motion in the bodyweight squat. Using an arms-up position should be considered, especially for the OW population, to increase the benefits of the bodyweight squat by increasing the range of motion.

  15. Overweight Kidney Transplant Recipients Are at Risk of Being Overdosed Following Standard Bodyweight-Based Tacrolimus Starting Dose

    PubMed Central

    Andrews, Louise M.; de Winter, Brenda C.M.; Tang, Jiang-Tao; Shuker, Nauras; Bouamar, Rachida; van Schaik, Ron H.N.; Koch, Birgit C.P.; van Gelder, Teun; Hesselink, Dennis A.

    2017-01-01

    Background Bodyweight-based dosing of tacrolimus (Tac) is considered standard care, even though the available evidence is thin. An increasing proportion of transplant recipients is overweight, prompting the question if the starting dose should always be based on bodyweight. Methods For this analysis, data were used from a randomized-controlled trial in which patients received either a standard Tac starting dose or a dose that was based on CYP3A5 genotype. The hypothesis was that overweight patients would have Tac overexposure following standard bodyweight-based dosing. Results Data were available for 203 kidney transplant recipients, with a median body mass index (BMI) of 25.6 (range, 17.2-42.2). More than 50% of the overweight or obese patients had a Tac predose concentration above the target range. The CYP3A5 nonexpressers tended to be above target when they weighed more than 67.5 kg or had a BMI of 24.5 or higher. Dosing guidelines were proposed with a decrease up to 40% in Tac starting doses for different BMI groups. The dosing guideline for patients with an unknown genotype was validated using the fixed-dose versus concentration controlled data set. Conclusions This study demonstrates that dosing Tac solely on bodyweight results in overexposure in more than half of overweight or obese patients.

  16. Comparison of the acute metabolic responses to traditional resistance, body-weight, and battling rope exercises.

    PubMed

    Ratamess, Nicholas A; Rosenberg, Joseph G; Klei, Samantha; Dougherty, Brian M; Kang, Jie; Smith, Charles R; Ross, Ryan E; Faigenbaum, Avery D

    2015-01-01

    The purpose of this study was to quantify and compare the acute metabolic responses to resistance exercise protocols comprising free-weight, body-weight, and battling rope (BR) exercises. Ten resistance-trained men (age = 20.6 ± 1.3 years) performed 13 resistance exercise protocols on separate days in random order consisting of only one exercise per session. For free-weight exercise protocols, subjects performed 3 sets of up to 10 repetitions with 75% of their 1 repetition maximum. For the push-up (PU) and push-up on a BOSU ball protocols, subjects performed 3 sets of 20 repetitions. For the burpee and PU with lateral crawl protocols, subjects performed 3 sets of 10 repetitions. For the plank and BR circuit protocols, subjects performed 3 sets of 30-second bouts. A standard 2-minute rest interval (RI) was used in between all sets for each exercise. Data were averaged for the entire protocol including work and RIs. Mean oxygen consumption was significantly greatest during the BR (24.6 ± 2.6 ml·kg·min) and burpee (22.9 ± 2.1 ml·kg·min) protocols. For the free-weight exercises, highest mean values were seen in the squat (19.6 ± 1.8 ml·kg·min), deadlift (18.9 ± 3.0 ml·kg·min), and lunge (17.3 ± 2.6 ml·kg·min). No differences were observed between PUs performed on the floor vs. on a BOSU ball. However, adding a lateral crawl to the PU significantly increased mean oxygen consumption (19.5 ± 2.9 ml·kg·min). The lowest mean value was seen during the plank exercise (7.9 ± 0.7 ml·kg·min). These data indicate performance of exercises with BRs and a body-weight burpee exercise elicit relatively higher acute metabolic demands than traditional resistance exercises performed with moderately heavy loading.

  17. Interlimb coordination in body-weight supported locomotion: A pilot study.

    PubMed

    Seiterle, Stefan; Susko, Tyler; Artemiadis, Panagiotis K; Riener, Robert; Igo Krebs, Hermano

    2015-08-20

    Locomotion involves complex neural networks responsible for automatic and volitional actions. During locomotion, motor strategies can rapidly compensate for any obstruction or perturbation that could interfere with forward progression. In this pilot study, we examined the contribution of interlimb pathways for evoking muscle activation patterns in the contralateral limb when a unilateral perturbation was applied and in the case where body weight was externally supported. In particular, the latency of neuromuscular responses was measured, while the stimulus to afferent feedback was limited. The pilot experiment was conducted with six healthy young subjects. It employed the MIT-Skywalker (beta-prototype), a novel device intended for gait therapy. Subjects were asked to walk on the split-belt treadmill, while a fast unilateral perturbation was applied mid-stance by unexpectedly lowering one side of the split-treadmill walking surfaces. Subject's weight was externally supported via the body-weight support system consisting of an underneath bicycle seat and the torso was stabilized via a loosely fitted chest harness. Both the weight support and the chest harness limited the afferent feedback. The unilateral perturbations evoked changes in the electromyographic activity of the non-perturbed contralateral leg. The latency of all muscle responses exceeded 100ms, which precludes the conjecture that spinal cord alone is responsible for the perturbation response. It suggests the role of supraspinal or midbrain level pathways at the inter-leg coordination during gait.

  18. Interlimb Coordination in Body-Weight Supported Locomotion: A Pilot Study

    PubMed Central

    Seiterle, Stefan; Susko, Tyler; Artemiadis, Panagiotis K.; Riener, Robert; Krebs, Hermano Igo

    2015-01-01

    Locomotion involves complex neural networks responsible for automatic and volitional actions. During locomotion, motor strategies can rapidly compensate for any obstruction or perturbation that could interfere with forward progression. In this pilot study, we examined the contribution of interlimb pathways for evoking muscle activation patterns in the contralateral limb when a unilateral perturbation was applied and in the case where body weight was externally supported. In particular, the latency of neuromuscular responses was measured, while the stimulus to afferent feedback was limited. The pilot experiment was conducted with six healthy young subjects. It employed the MIT-Skywalker (beta-prototype), a novel device intended for gait therapy. Subjects were asked to walk on the split-belt treadmill, while a fast unilateral perturbation was applied mid-stance by unexpectedly lowering one side of the split-treadmill walking surfaces. Subject's weight was externally supported via the body-weight support system consisting of an underneath bicycle seat and the torso was stabilized via a loosely fitted chest harness. Both the weight support and the chest harness limited the afferent feedback. The unilateral perturbations evoked changes in the electromyographic activity of the non-perturbed contralateral leg. The latency of all muscle responses exceeded 100 ms, which precludes the conjecture that spinal cord alone is responsible for the perturbation response. It suggests the role of supraspinal or midbrain level pathways at the inter-leg coordination during gait. PMID:25990210

  19. Survival protection by bodyweight in isolated scleroderma-related pulmonary artery hypertension.

    PubMed

    Marini, Carlo; Formichi, Bruno; Bauleo, Carolina; Michelassi, Claudio; Airò, Edoardo; Rossi, Giuseppe; Giuntini, Carlo

    2016-10-01

    In chronic heart failure (CHF) due to systemic cardiovascular disease, obese patients have better survival. Bodyweight versus survival was analyzed post hoc in subjects with limited scleroderma (SSc) and isolated pulmonary artery hypertension (PAH), i.e. with CHF due to pulmonary vascular disease. Rheumatologists referred scleroderma subjects for evaluation, and PAH was ascertained by right heart catheterization (RHC). Forty-nine SSc-PAH subjects were stratified by body mass index (BMI): obese 7 (14.3 %), overweight 11 (22.4 %), normal weight 21 (42.9 %), and underweight 10 (20.4 %) for 24-month follow-up and pooled together for long-term 72-month follow-up. Survival was analyzed by Kaplan-Meier method. Multivariate Cox proportional hazards modeling helped to assess variables associated to survival. At 24 months (17 events), survival increases with BMI across four groups (logrank for trend P = 0.031). By Cox multivariate mortality, best model included: BMI (P = 0.043), low lung diffusion (DLco, P = 0.007), and reduced stroke volume index (SVI, P = 0.017). At 72 month (37 events), higher BMI values were associated with better survival but not significantly (P = 0.076). By multivariate modeling BMI did not enter any model, whereas low DLco entered all (P < 0.001). Also low SVI (P = 0.02) and low mixed venous saturation (SvO2, P = 0.009) were associated with the prognosis. From PAH diagnosis to final event, BMI had small (5.4 %), but significant decline (P < 0.001). This is ascribed to CHF progression, and may explain BMI predictive power weakening. The results suggest BMI decline should be contrasted, DLco is useful for screening and with SVI and SvO2 for assessing prognosis and treatment.

  20. Effects of electroacupuncture at GB points on markers of osteoporosis and bodyweight in ovariectomised rats

    PubMed Central

    Wang, Hong-Du; Chen, Zhuang; Inoue, Isao; Fu, Shi-Jie; Shi, Xiao-Lin; Tang, Li; Zhang, Feng-Zheng; Jiang, Yang; Jiang, Hua

    2015-01-01

    Background Based on a description of acupuncture to treat a bone disease resembling osteoporosis in the ancient text of Huangdi Neijing, we aimed to assess the effects of electroacupuncture (EA) at GB points in ovariectomised (OVX) rats. Methods 40 female Wistar rats were randomly divided into four groups (n=10 each): ovariectomised model group (OVX); ovariectomised group treated with EA at GB points (OVX+GB); ovariectomised group treated with EA at non-GB points (OVX+N) in the hindlimb; and a sham surgery group (Sham). Three months after ovariectomy, rats in the OVX+GB and OVX+N groups received EA treatment for 3 months. Urine, blood and femur samples were collected from each animal for analysis. Results Bodyweight (BW) in the OVX+GB group decreased after EA treatment, reaching a minimum of ∼12% below the OVX and OVX+N groups at 1 month. Concentrations of urine deoxypyridinoline, a bone resorption marker, were significantly elevated in the OVX and OVX+N groups but not the OVX+GB group. Concentrations of serum bone specific alkaline phosphatase, a bone formation marker, were significantly higher in the OVX+GB group versus the Sham and OVX groups. Bone mineral density (BMD) did not differ between the OVX, OVX+GB and OVX+N groups, but was ∼10% lower than the Sham group. However, BMD/BW in the OVX+GB group was significantly higher than in the OVX and OVX+N groups and similar to the Sham group. Histological assessment of the femur showed that EA at GB points improved the bone architecture. Conclusions EA treatment at GB points had anti-osteoporotic effects in a rat model of osteoporosis. PMID:26245584

  1. Early warning of footpad dermatitis and hockburn in broiler chicken flocks using optical flow, bodyweight and water consumption.

    PubMed

    Dawkins, M S; Roberts, S J; Cain, R J; Nickson, T; Donnelly, C A

    2017-02-27

    Footpad dermatitis and hockburn are serious welfare and economic issues for the production of broiler (meat) chickens. The authors here describe the use of an inexpensive camera system that monitors the movements of broiler flocks throughout their lives and suggest that it is possible to predict, even in young birds, the cross-sectional prevalence at slaughter of footpad dermatitis and hockburn before external signs are visible. The skew and kurtosis calculated from the authors' camera-based optical flow system had considerably more power to predict these outcomes in the 50 flocks reported here than water consumption, bodyweight or mortality and therefore have the potential to inform improved flock management through giving farmers early warning of welfare issues. Further trials are underway to establish the generality of the results.

  2. HMG-coenzyme A reductase inhibition, type 2 diabetes, and bodyweight: evidence from genetic analysis and randomised trials

    PubMed Central

    Swerdlow, Daniel I; Preiss, David; Kuchenbaecker, Karoline B; Holmes, Michael V; Engmann, Jorgen E L; Shah, Tina; Sofat, Reecha; Stender, Stefan; Johnson, Paul C D; Scott, Robert A; Leusink, Maarten; Verweij, Niek; Sharp, Stephen J; Guo, Yiran; Giambartolomei, Claudia; Chung, Christina; Peasey, Anne; Amuzu, Antoinette; Li, KaWah; Palmen, Jutta; Howard, Philip; Cooper, Jackie A; Drenos, Fotios; Li, Yun R; Lowe, Gordon; Gallacher, John; Stewart, Marlene C W; Tzoulaki, Ioanna; Buxbaum, Sarah G; van der A, Daphne L; Forouhi, Nita G; Onland-Moret, N Charlotte; van der Schouw, Yvonne T; Schnabel, Renate B; Hubacek, Jaroslav A; Kubinova, Ruzena; Baceviciene, Migle; Tamosiunas, Abdonas; Pajak, Andrzej; Topor-Madry, Romanvan; Stepaniak, Urszula; Malyutina, Sofia; Baldassarre, Damiano; Sennblad, Bengt; Tremoli, Elena; de Faire, Ulf; Veglia, Fabrizio; Ford, Ian; Jukema, J Wouter; Westendorp, Rudi G J; de Borst, Gert Jan; de Jong, Pim A; Algra, Ale; Spiering, Wilko; der Zee, Anke H Maitland-van; Klungel, Olaf H; de Boer, Anthonius; Doevendans, Pieter A; Eaton, Charles B; Robinson, Jennifer G; Duggan, David; Kjekshus, John; Downs, John R; Gotto, Antonio M; Keech, Anthony C; Marchioli, Roberto; Tognoni, Gianni; Sever, Peter S; Poulter, Neil R; Waters, David D; Pedersen, Terje R; Amarenco, Pierre; Nakamura, Haruo; McMurray, John J V; Lewsey, James D; Chasman, Daniel I; Ridker, Paul M; Maggioni, Aldo P; Tavazzi, Luigi; Ray, Kausik K; Seshasai, Sreenivasa Rao Kondapally; Manson, JoAnn E; Price, Jackie F; Whincup, Peter H; Morris, Richard W; Lawlor, Debbie A; Smith, George Davey; Ben-Shlomo, Yoav; Schreiner, Pamela J; Fornage, Myriam; Siscovick, David S; Cushman, Mary; Kumari, Meena; Wareham, Nick J; Verschuren, W M Monique; Redline, Susan; Patel, Sanjay R; Whittaker, John C; Hamsten, Anders; Delaney, Joseph A; Dale, Caroline; Gaunt, Tom R; Wong, Andrew; Kuh, Diana; Hardy, Rebecca; Kathiresan, Sekar; Castillo, Berta A; van der Harst, Pim; Brunner, Eric J; Tybjaerg-Hansen, Anne; Marmot, Michael G; Krauss, Ronald M; Tsai, Michael; Coresh, Josef; Hoogeveen, Ronald C; Psaty, Bruce M; Lange, Leslie A; Hakonarson, Hakon; Dudbridge, Frank; Humphries, Steve E; Talmud, Philippa J; Kivimäki, Mika; Timpson, Nicholas J; Langenberg, Claudia; Asselbergs, Folkert W; Voevoda, Mikhail; Bobak, Martin; Pikhart, Hynek; Wilson, James G; Reiner, Alex P; Keating, Brendan J; Hingorani, Aroon D; Sattar, Naveed

    2015-01-01

    Summary Background Statins increase the risk of new-onset type 2 diabetes mellitus. We aimed to assess whether this increase in risk is a consequence of inhibition of 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR), the intended drug target. Methods We used single nucleotide polymorphisms in the HMGCR gene, rs17238484 (for the main analysis) and rs12916 (for a subsidiary analysis) as proxies for HMGCR inhibition by statins. We examined associations of these variants with plasma lipid, glucose, and insulin concentrations; bodyweight; waist circumference; and prevalent and incident type 2 diabetes. Study-specific effect estimates per copy of each LDL-lowering allele were pooled by meta-analysis. These findings were compared with a meta-analysis of new-onset type 2 diabetes and bodyweight change data from randomised trials of statin drugs. The effects of statins in each randomised trial were assessed using meta-analysis. Findings Data were available for up to 223 463 individuals from 43 genetic studies. Each additional rs17238484-G allele was associated with a mean 0·06 mmol/L (95% CI 0·05–0·07) lower LDL cholesterol and higher body weight (0·30 kg, 0·18–0·43), waist circumference (0·32 cm, 0·16–0·47), plasma insulin concentration (1·62%, 0·53–2·72), and plasma glucose concentration (0·23%, 0·02–0·44). The rs12916 SNP had similar effects on LDL cholesterol, bodyweight, and waist circumference. The rs17238484-G allele seemed to be associated with higher risk of type 2 diabetes (odds ratio [OR] per allele 1·02, 95% CI 1·00–1·05); the rs12916-T allele association was consistent (1·06, 1·03–1·09). In 129 170 individuals in randomised trials, statins lowered LDL cholesterol by 0·92 mmol/L (95% CI 0·18–1·67) at 1-year of follow-up, increased bodyweight by 0·24 kg (95% CI 0·10–0·38 in all trials; 0·33 kg, 95% CI 0·24–0·42 in placebo or standard care controlled trials and −0·15 kg, 95% CI −0·39 to 0·08 in intensive

  3. High-calcium diet with whey protein attenuates body-weight gain in high-fat-fed C57Bl/6J mice.

    PubMed

    Pilvi, Taru K; Korpela, Riitta; Huttunen, Minna; Vapaatalo, Heikki; Mervaala, Eero M

    2007-11-01

    An inverse relationship between Ca intake and BMI has been found in several studies. It has been suggested that Ca affects adipocyte metabolism via suppressing 1,25-dihydroxycholecalciferol (1,25(OH)2-D3) and decreases fat absorption. We studied the effect of Ca and milk proteins (whey and casein) on body weight in C57Bl/6J mice. Male mice, age 9 weeks, were divided into three groups (ten mice per group) receiving modified high-fat (60% of energy) diets. Two groups received a high-Ca diet (1.8% calcium carbonate (CaCO3)), with casein or whey protein (18% of energy), and one group received a low-Ca diet (0.4% CaCO3) with casein for 21 weeks. Food intake was measured daily and body weight twice per week. Body fat content (by dual-energy X-ray absorptiometry) of all mice and faecal Ca and fat excretion of seven mice/group were measured twice during the study. Final body weight (44.1 (SEM 1.1) g) and body fat content (41.6 (SEM 0.6) %) were significantly lower (P < 0.05) in the high-Ca whey group than in the low-Ca casein group (48.1 (SEM 0.8) g and 44.9 (SEM 0.8) %). Body weight and body fat content of the high-Ca casein group did not differ significantly from the low-Ca casein group even though serum 1,25(OH)2-D3 levels were significantly lower (P < 0.001) in both high-Ca groups than in the low-Ca casein group. Thus changes in serum 1,25(OH)2-D3 do not seem to affect body weight in this animal model. There was a significant difference in fat excretion between the high-Ca whey and low-Ca casein groups (3.9 (SEM 0.9) % in the high-Ca whey v. 1.4 (SEM 0.2) % in the low-Ca casein group; P < 0.05), which may partly explain the effect on body weight.

  4. IR gain monitor

    NASA Astrophysics Data System (ADS)

    Hilbert, Bryan

    2013-10-01

    The gain of the IR channel of WFC3 will be measured using a series of internal flat fields. Using knowledge gained from ground testing and previous cycles, we propose to collect flat field ramps which will be used to create photon transfer curves and give a measure of the gain. This continues the strategy of last cycle's gain monitor, in proposal 13080.

  5. Ultrasonographic evaluation of the adrenal glands in healthy dogs: repeatability, reproducibility, observer-dependent variability, and the effect of bodyweight, age and sex.

    PubMed

    Mogicato, G; Layssol-Lamour, C; Conchou, F; Diquelou, A; Raharison, F; Sautet, J; Concordet, D

    2011-02-05

    Adrenal length and width were determined from two-dimensional ultrasound longitudinal images. In study 1, 540 measurements of adrenal glands were attempted from five healthy beagle dogs by three different observers with different levels of expertise in ultrasonography, to determine the variability of adrenal gland measurements. Of these, 484 measurements were included in the statistical analysis, since 16 measurements of the left adrenal gland and 40 for the right could not be visualised by the observer. In study 2, a single measurement of both adrenal glands was taken from each of 146 dogs by the most trained observer from study 1, and the effects of different health status (healthy dogs v dogs with non-adrenal diseases), bodyweight, age and sex were assessed. A total of 267 measurements were included in the statistical analysis. The lowest intra- and inter-day coefficient of variation values were observed for the left adrenal gland and by the most trained observer. The health status had no statistically significant effect on adrenal gland length or width, whereas age had a significant effect only for the left adrenal gland (the greater the age, the greater the width or length) and sex had a significant effect only for the right adrenal gland (the width was larger in males and the length larger in females). The bodyweight had a significant effect for the length of both adrenal glands (the greater the bodyweight, the greater the length), but not the width. The differences between sd and coefficient of variation values for the width of the left adrenal gland were not statistically significant between the three observers, whereas they were statistically significant for the right adrenal gland.

  6. Can a Single Session of a Community-Based Group Exercise Program Combining Step Aerobics and Bodyweight Resistance Exercise Acutely Reduce Blood Pressure?

    PubMed Central

    Mendes, Romeu; Sousa, Nelson; Garrido, Nuno; Cavaco, Braulio; Quaresma, Luís; Reis, Victor Machado

    2014-01-01

    This study aimed to analyze the acute effects of a single session of a community-based group exercise program combining step aerobics and bodyweight resistance exercise on blood pressure in healthy young adult women. Twenty-three healthy young adult women (aged 31.57 ± 7.87 years) participated in two experimental sessions (exercise and control) in a crossover study design. Blood pressure was monitored before, immediately after and at 10, 20 and 30 min of recovery. The exercise session consisted of four phases: 1) a warm-up (5 min of dance aerobics); 2) aerobic exercise training (30 min of step aerobics); 3) resistance exercise training (six sets of 12 repetitions of three bodyweight exercises in a circuit mode, 10 min); and 4) a cool-down (5 min of breathing and flexibility exercises); totaling 50 min of duration. Systolic blood pressure after exercise was significantly lower compared to control at the 10th min (−10.83 ± 2.13 vs. −2.6 ± 2.13 mmHg; p = 0.009), 20th min (−11.26 ± 2.13 vs. −3.04 ± 2.13 mmHg; p = 0.009) and 30th min of recovery (−10.87 ± 2.39 vs. −0.48 ± 2.39 mmHg; p = 0.004). A single session of a community-based group exercise program combining step aerobics and bodyweight resistance exercise was effective in inducing significant post-exercise hypotension in healthy young adult women. This type of low-cost exercise interventions may have an important role in the prevention of cardiovascular diseases and in community health promotion. PMID:25713644

  7. Effects of lifestyle intervention and meal replacement on glycaemic and body-weight control in Chinese subjects with impaired glucose regulation: a 1-year randomised controlled trial.

    PubMed

    Xu, Dan-Feng; Sun, Jian-Qin; Chen, Min; Chen, Yan-Qiu; Xie, Hua; Sun, Wei-Jia; Lin, Yi-Fan; Jiang, Jing-Jing; Sun, Wei; Chen, Ai-Fang; Tang, Qian-Ru

    2013-02-14

    The purpose of the present study was to evaluate the impact of a lifestyle intervention programme, combined with a daily low-glycaemic index meal replacement, on body-weight and glycaemic control in subjects with impaired glucose regulation (IGR). Subjects with IGR were randomly assigned to an intervention group (n 46) and a control group (n 42). Both groups received health counselling at baseline. The intervention group also received a daily meal replacement and intensive lifestyle intervention to promote healthy eating habits during the first 3 months of the study, and follow-up visits performed monthly until the end of the 1-year study. Outcome measurements included changes in plasma glucose, glycated Hb (HbA1c), plasma lipids, body weight, blood pressure and body composition (such as body fat mass and visceral fat area). The results showed that body-weight loss after 1 year was significant in the intervention group compared with the control group (-1·8 (SEM 0·35) v. -0·6 (SEM 0·40) 2·5 kg, P<0·05). The 2 h plasma glucose concentration decreased 1·24 mmol/l in the intervention group and increased 0·85 mmol/l in the control group (P<0·05) compared with their baseline, respectively. A 5 kg body-weight loss at 1 year was associated with a decrease of 1·49 mmol/l in 2 h plasma glucose (P<0·01). The incidence of normal glucose regulation (NGR) in the two groups was significantly different (P=0·001). In conclusion, the combination of regular contact, lifestyle advice and meal replacement is beneficial in promoting IGR to NGR.

  8. Effects of Mini-Volume Priming During Cardiopulmonary Bypass on Clinical Outcomes in Low-Bodyweight Neonates: Less Transfusion and Postoperative Extracorporeal Membrane Oxygenation Support.

    PubMed

    Kim, Sang Yoon; Cho, Sungkyu; Choi, Eunseok; Kim, Woong-Han

    2016-01-01

    Mixing of autologous blood with priming volume has relatively significant effects on blood composition, especially in low-bodyweight neonates. In an effort to reduce these effects, mini-volume priming (MP) has been applied in cardiopulmonary bypass (CPB). The present study was designed to examine the effect of MP on clinical outcomes of low-bodyweight neonates undergoing open heart surgery.We retrospectively reviewed medical records of low-bodyweight (2.5 kg or less) neonates who underwent open heart surgery in our center from January 2000 to December 2014. A total of 64 patients were included. MP was introduced in 2007, and became a routine protocol in 2009. Preoperative and intraoperative characteristics included age, bodyweight, RACHS-1, priming volume, CPB time, and aortic cross-clamp time, transfusion, and hematocrit during CPB. Clinical outcomes included 30-day mortality, postoperative extracorporeal membrane oxygenation (ECMO) support, open sternum status, prolonged mechanical ventilation care (>7 days), and acute renal failure. MP was utilized in 39 patients and conventional priming (CP) was used in 25 patients. The priming volume decreased to 126.0 mL in the MP group compared with 321.6 mL in the CP group. Transfusion volume during CPB was 87.3 mL in the MP group versus 226.8 mL in the CP group, and the difference was statistically significant (P < 0.001). Hematocrit at the end of the CPB and maximal decrease of hematocrit during CPB were not significantly different between the two groups. The 30-day mortality rate was 12.8% in the MP group versus 20.0% in the CP group. Postoperative ECMO support was performed in 5.1% of patients in the MP group versus 17.4% of patients in the CP group. Open sternum status was required in 20.8% of patients in the MP group versus 10.3% of patients in the CP group, and prolonged ventilator care was required in 54.2% of patients in the MP group versus 38.5% of patients in the CP group. However, no statistical

  9. Antidepressants and Weight Gain

    MedlinePlus

    Diseases and Conditions Depression (major depressive disorder) Can antidepressants cause weight gain? Answers from Daniel K. Hall-Flavin, M.D. Weight gain is a possible side effect of nearly all antidepressants. ...

  10. IR Gain Monitor

    NASA Astrophysics Data System (ADS)

    Hilbert, Bryan

    2012-10-01

    The gain of the IR channel of WFC3 will be measured using a series of internal flat fields. Using knowledge gained from ground testing and previous cycles, we propose to collect flat field ramps which will be used to create photon transfer curves and give a measure of the gain.

  11. Effect of body weight gain on insulin sensitivity after retirement from exercise training

    NASA Technical Reports Server (NTRS)

    Dolkas, Constantine B.; Rodnick, Kenneth J.; Mondon, Carl E.

    1990-01-01

    The effect of the body-weight gain after retirement from an exercise-training program on the retained increase in insulin sensitivity elicited by the training was investigated in exercise-trained (ET) rats. Insulin sensitivity was assessed by oral glucose tolerance and insulin suppression tests immediately after training and during retirement. Results show that, compared with sedentary controls, exercise training enhanced insulin-induced glucose uptake, but the enhanced sensitivity was gradually lost with the end of running activity until after seven days of retirement, when it became equal to that of controls. This loss of enhanced sensitivity to insulin was associated with an accelerated gain in body weight beginning one day after the start of retirement. However, those animals that gained weight only at rates similar to those of control rats, retained their enhanced sensitivity to insulin.

  12. Gaining Cyber Dominance

    DTIC Science & Technology

    2015-01-01

    2014 Carnegie Mellon University Gaining Cyber Dominance Software Engineering Institute Carnegie Mellon University NETCOM G3/5/7 TREX January 2015...JAN 2015 2. REPORT TYPE N/A 3. DATES COVERED 4. TITLE AND SUBTITLE Gaining Cyber Dominance 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c...2014) 4 GCD Overview January 2015 © 2014 Carnegie Mellon University FY15 Initiatives Gaining Cyber Dominance Program • Army topology development

  13. Weight gain - unintentional

    MedlinePlus

    ... trying to do so can have many causes. Metabolism slows down as you age . This can cause weight gain if you eat too much, eat the wrong foods, or do not get enough exercise. Drugs that can cause weight gain include: Birth ...

  14. Invention and Gain Analysis.

    ERIC Educational Resources Information Center

    Weber, Robert J.; Dixon, Stacey

    1989-01-01

    Gain analysis is applied to the invention of the sewing needle as well as different sewing implements and modes of sewing. The analysis includes a two-subject experiment. To validate the generality of gain heuristics and underlying switching processes, the invention of the assembly line is also analyzed. (TJH)

  15. Digital automatic gain control

    NASA Technical Reports Server (NTRS)

    Uzdy, Z.

    1980-01-01

    Performance analysis, used to evaluated fitness of several circuits to digital automatic gain control (AGC), indicates that digital integrator employing coherent amplitude detector (CAD) is best device suited for application. Circuit reduces gain error to half that of conventional analog AGC while making it possible to automatically modify response of receiver to match incoming signal conditions.

  16. Bodyweight and carcass characteristics of Somali goats fed hay supplemented with graded levels of peanut cake and wheat bran mixture.

    PubMed

    Melaku, Solomon; Betsha, Simret

    2008-10-01

    The experiment was conducted for ninety days of feeding trial at Haramaya University, Ethiopia using twenty four yearling male Somali goats weighing 20.4 +/- 2.02 (mean +/- SD) with the objectives to evaluate the effect of supplementation of peanut cake and wheat bran mixture (3:1) on body weight (BW) gain and carcass characteristics of Somali goats. The experiment was arranged with six blocks and four treatments in a randomized complete block design. The treatments were ad libitum feeding of hay (T1, control) and supplementation with 200 g (T2), 300 g (T3) and 400 g (T4) peanut cake and wheat bran mixture on dry matter (DM) basis. Supplementation reduced (P < 0.001) hay DM intake, but increased (P < 0.001) total DM intake at 300 g DM (T3) and 400 g DM (T4) level of supplementation compared to the control treatment. Daily BW gain, final BW, empty BW, hot carcass weight and dressing percent were higher (P < 0.001) in the supplemented treatments. Goats on the medium (T3) level of supplementation had significantly heavier (P < 0.001) liver and more muscle deposition, whereas those on hay alone (T1) exhibited heavier bone, head as well as gut contents (P < 0.05). It was concluded that supplementation of Somali goats with the different levels of peanut cake and wheat bran mixture promoted BW gain, dressing percentage and increased the proportion of edible offals. Similarity between the different levels of supplementation used in this study with regard to BW and carcass characteristics favours the use of the low (T2) or medium (T3) level than the high (T4) level of supplementation.

  17. Indoor acoustic gain design

    NASA Astrophysics Data System (ADS)

    Concha-Abarca, Justo Andres

    2002-11-01

    The design of sound reinforcement systems includes many variables and usually some of these variables are discussed. There are criteria to optimize the performance of the sound reinforcement systems under indoor conditions. The equivalent acoustic distance, the necessary acoustic gain, and the potential acoustic gain are parameters which must be adjusted with respect to the loudspeaker array, electric power and directionality of loudspeakers, the room acoustics conditions, the distance and distribution of the audience, and the type of the original sources. The design and installation of front of the house and monitoring systems have individual criteria. This article is about this criteria and it proposes general considerations for the indoor acoustic gain design.

  18. Asthma Triggers: Gain Control

    MedlinePlus

    ... of Page Additional resources An Introduction to Indoor Air Quality: Biological Pollutants Help Your Child Gain Control Over ... exhaust, smoke, road dust and factory emissions. Outdoor air quality is also affected by pollen from plants, crops ...

  19. Preventing Weight Gain

    MedlinePlus

    ... body composition gradually shifts — the proportion of muscle decreases and the proportion of fat increases. This shift slows their metabolism, making it easier to gain weight. In addition, some people become less physically ...

  20. Whey protein isolate and glycomacropeptide decrease weight gain and alter body composition in male Wistar rats.

    PubMed

    Royle, Peter J; McIntosh, Graeme H; Clifton, Peter M

    2008-07-01

    The effect of feed protein type on body composition and growth has been examined. Evidence exists that whey protein concentrate is effective at limiting body fat expansion. The presence of caseinomacropeptide, a mixture of glycosylated and non-glycosylated carbohydrate residues, in particular glycomacropeptide (GMP) in whey protein concentrate may be important for this effect. The influence of whey protein isolate (WPI) and GMP on weight gain and body composition was examined by feeding Wistar rats ad libitum for 7 weeks with five semi-purified American Institute of Nutrition-based diets differing in protein type: (1) casein; (2) barbequed beef; (3) control WPI (no GMP); (4) WPI+GMP at 100 g/kg; (5) WPI+GMP at 200 g/kg. Body composition was assessed, and plasma samples were assayed for TAG, insulin and glucose. Body-weight gain was lower (- 21 %) on the control WPI diet relative to casein, with a non-significant influence associated with GMP inclusion (- 30 %), the effect being equivalent at both levels of GMP addition. Renal and carcass fat mass were reduced in the highest GMP diet when compared with WPI (P < 0.05). Plasma insulin was lowered by GMP at the highest addition compared with WPI alone (- 53 %; P < 0.01). Plasma TAG in the WPI+GMP (200 g/kg) group were lower (- 27 %; P < 0.05) than the casein and beef groups. In conclusion, GMP appears to have a significant additional influence when combined with WPI on fat accumulation. WPI alone appears to have the predominant influence accounting for 70 % of the overall effect on body-weight gain. Mechanisms for this effect have not been identified but food intake was not responsible.

  1. Should I Gain Weight?

    MedlinePlus

    ... If you're having trouble with your body image, talk about how you feel with someone you like and trust who's been through it — maybe a parent, doctor, counselor, coach, or teacher. continue It's the Growth, Not the Gain No ...

  2. Plasma exogenous creatinine clearance in clinically healthy cats: comparison with urinary exogenous creatinine clearance, tentative reference intervals and indexation to bodyweight.

    PubMed

    Reynolds, B S; Massal, M R; Nguyen, P; Grégoire, L L; Périgaud, A E; Concordet, D; Biourge, V; Lefebvre, H P

    2014-10-01

    Glomerular filtration rate (GFR) is considered to be the best indicator of overall kidney function. The major objectives of this study were to compare plasma exogenous creatinine clearance (PECC) with a reference method, to establish reference intervals (RIs) for PECC and to assess the effects of indexation of GFR to bodyweight (BW) in cats. PECC was compared with urinary clearance of exogenous creatinine (UECC) in six clinically healthy domestic shorthair cats (experiment 1). Tentative RIs were determined according to current guidelines and the effects of indexation to BW and of covariables on GFR were assessed in 43 clinically healthy cats of various breeds (experiment 2). PECC was 15% higher than UECC (P <0.01), but the two estimates were strongly correlated (r(2)=0.97, P = 0.001). RIs for PECC were 6.4-21.3 mL/min or 1.2-4.9 mL/min/kg. The absolute (i.e. non-indexed) GFR value was not dependent on BW. Thus, indexation of GFR to BW in cats would not standardize the GFR value, but could introduce bias in clinical interpretation. Significant effects of breed, plasma protein concentration and plasma albumin concentration on GFR were demonstrated. Plasma concentrations of urea and creatinine, when assessed separately, were also weakly correlated with GFR in healthy cats. These combined findings contribute to a better understanding of renal function assessment in cats.

  3. Helicopter high gain control

    NASA Technical Reports Server (NTRS)

    Cunningham, T. B.; Nunn, E. C.

    1979-01-01

    High gain control is explored through a design study of the CH-47B helicopter. The plans are designed to obtain the maximum bandwidth possible given the hardware constraints. Controls are designed with modal control theory to specific bandwidths and closed loop mode shapes. Comparisons are made to an earlier complementary filter approach. Bandwidth improvement by removal of limitations is explored in order to establish hardware and mechanization options. Improvements in the pitch axis control system and in the rate gyro sensor noise characteristics in all axes are discussed. The use of rotor state feedback is assessed.

  4. Bipolar Medications and Weight Gain

    MedlinePlus

    Bipolar medications and weight gain Do all bipolar medications cause weight gain? Answers from Daniel K. Hall-Flavin, M. ... disorder can be treated with a number of medications. Some of these medications can increase your appetite ...

  5. Acting to gain information

    NASA Technical Reports Server (NTRS)

    Rosenchein, Stanley J.; Burns, J. Brian; Chapman, David; Kaelbling, Leslie P.; Kahn, Philip; Nishihara, H. Keith; Turk, Matthew

    1993-01-01

    This report is concerned with agents that act to gain information. In previous work, we developed agent models combining qualitative modeling with real-time control. That work, however, focused primarily on actions that affect physical states of the environment. The current study extends that work by explicitly considering problems of active information-gathering and by exploring specialized aspects of information-gathering in computational perception, learning, and language. In our theoretical investigations, we analyzed agents into their perceptual and action components and identified these with elements of a state-machine model of control. The mathematical properties of each was developed in isolation and interactions were then studied. We considered the complexity dimension and the uncertainty dimension and related these to intelligent-agent design issues. We also explored active information gathering in visual processing. Working within the active vision paradigm, we developed a concept of 'minimal meaningful measurements' suitable for demand-driven vision. We then developed and tested an architecture for ongoing recognition and interpretation of visual information. In the area of information gathering through learning, we explored techniques for coping with combinatorial complexity. We also explored information gathering through explicit linguistic action by considering the nature of conversational rules, coordination, and situated communication behavior.

  6. Leading Gainful Employment Metric Reporting

    ERIC Educational Resources Information Center

    Powers, Kristina; MacPherson, Derek

    2016-01-01

    This chapter will address the importance of intercampus involvement in reporting of gainful employment student-level data that will be used in the calculation of gainful employment metrics by the U.S. Department of Education. The authors will discuss why building relationships within the institution is critical for effective gainful employment…

  7. Linoleic acid causes greater weight gain than saturated fat without hypothalamic inflammation in the male mouse.

    PubMed

    Mamounis, Kyle J; Yasrebi, Ali; Roepke, Troy A

    2017-02-01

    A significant change in the Western diet, concurrent with the obesity epidemic, was a substitution of saturated fatty acids with polyunsaturated, specifically linoleic acid (LA). Despite increasing investigation on type as well as amount of fat, it is unclear which fatty acids are most obesogenic. The objective of this study was to determine the obesogenic potency of LA vs. saturated fatty acids and the involvement of hypothalamic inflammation. Forty-eight mice were divided into four groups: low-fat or three high-fat diets (HFDs, 45% kcals from fat) with LA comprising 1%, 15% and 22.5% of kilocalories, the balance being saturated fatty acids. Over 12 weeks, bodyweight, body composition, food intake, calorimetry, and glycemia assays were performed. Arcuate nucleus and blood were collected for mRNA and protein analysis. All HFD-fed mice were heavier and less glucose tolerant than control. The diet with 22.5% LA caused greater bodyweight gain, decreased activity, and insulin resistance compared to control and 1% LA. All HFDs elevated leptin and decreased ghrelin in plasma. Neuropeptides gene expression was higher in 22.5% HFD. The inflammatory gene Ikk was suppressed in 1% and 22.5% LA. No consistent pattern of inflammatory gene expression was observed, with suppression and augmentation of genes by one or all of the HFDs relative to control. These data indicate that, in male mice, LA induces obesity and insulin resistance and reduces activity more than saturated fat, supporting the hypothesis that increased LA intake may be a contributor to the obesity epidemic.

  8. Open label study of the effect of amantadine on weight gain induced by olanzapine.

    PubMed

    Bahk, Won-Myong; Lee, Kyoung-Uk; Chae, Jeong-Ho; Pae, Chi-Un; Jun, Taeyoun; Kim, Kwang-Soo

    2004-04-01

    The purpose of the present paper was to investigate the effects of the dopamine agonist amantadine in those patients with weight gain induced by olanzapine. An open trial was conducted in those patients who gained >3 kg in weight induced by olanzapine use. All subjects were evaluated by weight, body mass index (BMI), the Brief Psychiatric Rating Scale (BPRS), and the Extrapyramidal Symptom Rating Scale (ESRS) before and after the use of amantadine in addition to olanzapine. Twenty-five of 30 enrolled patients completed the present study. Mean bodyweight and BMI was increased by 6.44 +/- 4.42 kg and 5.04 +/- 3.47 kg/m2 significantly with olanzapine alone (P < 0.001). When amantadine and olanzapine were used together, the average weight and BMI decreased by 1.07 +/- 3.19 kg and 0.84 +/- 2.5 kg/m2, but did not have statistical significance. The average values of BPRS showed a significant decrease (P < 0.001). No significant changes were present in ESRS. Amantadine did not have an effect on weight gain induced by olanzapine. Randomized placebo-controlled prospective studies are needed.

  9. Weight gain is associated with medial contact site of subthalamic stimulation in Parkinson's disease.

    PubMed

    Růžička, Filip; Jech, Robert; Nováková, Lucie; Urgošík, Dušan; Vymazal, Josef; Růžička, Evžen

    2012-01-01

    The aim of our study was to assess changes in body-weight in relation to active electrode contact position in the subthalamic nucleus. Regular body weight measurements were done in 20 patients with advanced Parkinson's disease within a period of 18 months after implantation. T1-weighted (1.5T) magnetic resonance images were used to determine electrode position in the subthalamic nucleus and the Unified Parkinson's disease rating scale (UPDRS-III) was used for motor assessment. The distance of the contacts from the wall of the third ventricle in the mediolateral direction inversely correlated with weight gain (r = -0.55, p<0.01) and with neurostimulation-related motor condition expressed as the contralateral hemi-body UPDRS-III (r = -0.42, p<0.01). Patients with at least one contact within 9.3 mm of the wall experienced significantly greater weight gain (9.4 ± (SD)4.4 kg, N = 11) than those with both contacts located laterally (3.9 ± 2.7 kg, N = 9) (p<0.001). The position of the active contact is critical not only for motor outcome but is also associated with weight gain, suggesting a regional effect of subthalamic stimulation on adjacent structures involved in the central regulation of energy balance, food intake or reward.

  10. Improved Gain Microstrip Patch Antenna

    DTIC Science & Technology

    2015-08-06

    08-2015 Publication Improved Gain Microstrip Patch Antenna David A. Tonn Naval Under Warfare Center Division, Newport 1176 Howell St., Code 00L...Distribution A An antenna for mounting on a ground plane includes a dielectric substrate for mounting on the ground plane. A conductive patch...GAIN MICROSTRIP PATCH ANTENNA STATEMENT OF GOVERNMENT INTEREST [0001] The invention described herein may be manufactured and used by or for the

  11. Adaptive allocation of attentional gain.

    PubMed

    Scolari, Miranda; Serences, John T

    2009-09-23

    Humans are adept at distinguishing between stimuli that are very similar, an ability that is particularly crucial when the outcome is of serious consequence (e.g., for a surgeon or air-traffic controller). Traditionally, selective attention was thought to facilitate perception by increasing the gain of sensory neurons tuned to the defining features of a behaviorally relevant object (e.g., color, orientation, etc.). In contrast, recent mathematical models counterintuitively suggest that, in many cases, attentional gain should be applied to neurons that are tuned away from relevant features, especially when discriminating highly similar stimuli. Here we used psychophysical methods to critically evaluate these "ideal observer" models. The data demonstrate that attention enhances the gain of the most informative sensory neurons, even when these neurons are tuned away from the behaviorally relevant target feature. Moreover, the degree to which an individual adopted optimal attentional gain settings by the end of testing predicted success rates on a difficult visual discrimination task, as well as the amount of task improvement that occurred across repeated testing sessions (learning). Contrary to most traditional accounts, these observations suggest that the primary function of attentional gain is not to enhance the representation of target features per se, but instead to optimize performance on the current perceptual task. Additionally, individual differences in gain suggest that the operating characteristics of low-level attentional phenomena are not stable trait-like attributes and that variability in how attention is deployed may play an important role in determining perceptual abilities.

  12. Developmental gains in visuospatial memory predict gains in mathematics achievement.

    PubMed

    Li, Yaoran; Geary, David C

    2013-01-01

    Visuospatial competencies are related to performance in mathematical domains in adulthood, but are not consistently related to mathematics achievement in children. We confirmed the latter for first graders and demonstrated that children who show above average first-to-fifth grade gains in visuospatial memory have an advantage over other children in mathematics. The study involved the assessment of the mathematics and reading achievement of 177 children in kindergarten to fifth grade, inclusive, and their working memory capacity and processing speed in first and fifth grade. Intelligence was assessed in first grade and their second to fourth grade teachers reported on their in-class attentive behavior. Developmental gains in visuospatial memory span (d = 2.4) were larger than gains in the capacity of the central executive (d = 1.6) that in turn were larger than gains in phonological memory span (d = 1.1). First to fifth grade gains in visuospatial memory and in speed of numeral processing predicted end of fifth grade mathematics achievement, as did first grade central executive scores, intelligence, and in-class attentive behavior. The results suggest there are important individual differences in the rate of growth of visuospatial memory during childhood and that these differences become increasingly important for mathematics learning.

  13. High current gain transistor laser

    PubMed Central

    Liang, Song; Qiao, Lijun; Zhu, Hongliang; Wang, Wei

    2016-01-01

    A transistor laser (TL), having the structure of a transistor with multi-quantum wells near its base region, bridges the functionality gap between lasers and transistors. However, light emission is produced at the expense of current gain for all the TLs reported up to now, leading to a very low current gain. We propose a novel design of TLs, which have an n-doped InP layer inserted in the emitter ridge. Numerical studies show that a current flow aperture for only holes can be formed in the center of the emitter ridge. As a result, the common emitter current gain can be as large as 143.3, which is over 15 times larger than that of a TL without the aperture. Besides, the effects of nonradiative recombination defects can be reduced greatly because the flow of holes is confined in the center region of the emitter ridge. PMID:27282466

  14. Welfare Gains from Financial Liberalization

    PubMed Central

    Townsend, Robert M.; Ueda, Kenichi

    2010-01-01

    Financial liberalization has been a controversial issue, as empirical evidence for growth enhancing effects is mixed. Here, we find sizable welfare gains from liberalization (cost to repression), though the gain in economic growth is ambiguous. We take the view that financial liberalization is a government policy that alters the path of financial deepening, while financial deepening is endogenously chosen by agents given a policy and occurs in transition towards a distant steady state. This history-dependent view necessitates the use of simulation analysis based on a growth model. Our application is a specific episode: Thailand from 1976 to 1996. PMID:20806055

  15. Factors Affecting Auditory Training Gains.

    ERIC Educational Resources Information Center

    Moreau, Roberta M.

    1980-01-01

    A study was undertaken to determine which of nine variables were most related to success in auditory training, using as Ss 43 students at the National Technical Institute for the Deaf. Findings showed that the single largest contributing factor to postcourse gain was the entering English score. (PHR)

  16. Impaired H-Reflex Gain during Postural Loaded Locomotion in Individuals Post-Stroke

    PubMed Central

    Liang, Jing Nong; Brown, David A.

    2015-01-01

    Objective Successful execution of upright locomotion requires coordinated interaction between controllers for locomotion and posture. Our earlier research supported this model in the non-impaired and found impaired interaction in the post-stroke nervous system during locomotion. In this study, we sought to examine the role of the Ia afferent spinal loop, via the H-reflex response, under postural influence during a locomotor task. We tested the hypothesis that the ability to increase stretch reflex gain in response to postural loads during locomotion would be reduced post-stroke. Methods Fifteen individuals with chronic post-stroke hemiparesis and 13 non-impaired controls pedaled on a motorized cycle ergometer with specialized backboard support system under (1) seated supported, and (2) non-seated postural-loaded conditions, generating matched pedal force outputs of two levels. H-reflexes were elicited at 90°crank angle. Results We observed increased H-reflex gain with postural influence in non-impaired individuals, but a lack of increase in individuals post-stroke. Furthermore, we observed decreased H-reflex gain at higher postural loads in the stroke-impaired group. Conclusion These findings suggest an impaired Ia afferent pathway potentially underlies the defects in the interaction between postural and locomotor control post-stroke and may explain reduced ability of paretic limb support during locomotor weight-bearing in individuals post-stroke. Significance These results support the judicious use of bodyweight support training when first helping individuals post-stroke to regain locomotor pattern generation and weight-bearing capability. PMID:26629996

  17. Sweetening yoghurt with glucose, but not with saccharin, promotes weight gain and increased fat pad mass in rats.

    PubMed

    Boakes, Robert A; Kendig, Michael D; Martire, Sarah I; Rooney, Kieron B

    2016-10-01

    The claim that non-nutritive sweeteners accelerate body weight gain by disrupting sweet-calorie associations was tested in two experiments using rats. The experiments were modelled on a key study from a series of experiments reporting greater body weight gain in rats fed yoghurt sweetened with saccharin than with glucose (Swithers & Davidson, 2008). Both of the current experiments likewise compared groups fed saccharin- or glucose-sweetened yoghurt in addition to chow and water, while Experiment 1 included a third group (Control) given unsweetened yoghurt. In Experiment 1, but not in Experiment 2, rats were initially exposed to both saccharin- and glucose-sweetened yoghurts to assess their relative palatability. We also tested whether the provision of an energy-dense sweet biscuit would augment any effects of saccharin on food intake and weight gain, as seemingly predicted by Swithers and Davidson (2008). In Experiment 1 there were no differences in body weight gain or fat pad mass between the Saccharin and Control group, whereas the Glucose group was the heaviest by the final 5 weeks and at cull had the largest fat pads. Greater acceptance of saccharin predicted more weight gain over the whole experiment. Consistent with past reports, fasting blood glucose and insulin measures did not differ between the Saccharin and Control groups, but suggested some impairment of insulin sensitivity in the Glucose group. Experiment 2 found similar effects of glucose on fat mass, but not on body weight gain. In summary, adding saccharin had no detectable effects on body-weight regulation, whereas the effects of glucose on fat pad mass were consistent with previous studies reporting more harmful effects of sugars compared to non-nutritive sweeteners.

  18. Photomultiplier tube gain regulating system

    DOEpatents

    Johnson, Wayne F.

    1976-01-01

    This invention relates to an improved system for regulating the gain of a photomultiplier tube, and was designed for use with the photomultiplier tubes of a GeMSAEC fast analyzers. It has the following advantages over the prior system: noise is virtually eliminated; sample analysis can begin after 3 to 4 revolutions of the rotor; fluorescent and light scattering solutions can be used as a reference; and the reference solution can be in any cuvette on the rotor.

  19. Stochastic Gain in Population Dynamics

    NASA Astrophysics Data System (ADS)

    Traulsen, Arne; Röhl, Torsten; Schuster, Heinz Georg

    2004-07-01

    We introduce an extension of the usual replicator dynamics to adaptive learning rates. We show that a population with a dynamic learning rate can gain an increased average payoff in transient phases and can also exploit external noise, leading the system away from the Nash equilibrium, in a resonancelike fashion. The payoff versus noise curve resembles the signal to noise ratio curve in stochastic resonance. Seen in this broad context, we introduce another mechanism that exploits fluctuations in order to improve properties of the system. Such a mechanism could be of particular interest in economic systems.

  20. Scalar gain interpretation of large order filters

    NASA Technical Reports Server (NTRS)

    Mason, Paul A. C.; Mook, D. Joseph

    1993-01-01

    A technique is developed which demonstrates how to interpret a large fully-populated filter gain matrix as a set of scalar gains. The inverse problem is also solved, namely, how to develop a large-order filter gain matrix from a specified set of scalar gains. Examples are given to illustrate the method.

  1. A gain-coefficient switched Alexandrite laser

    NASA Astrophysics Data System (ADS)

    Lee, Chris J.; van der Slot, Peter J. M.; Boller, Klaus-J.

    2013-01-01

    We report on a gain-coefficient switched Alexandrite laser. An electro-optic modulator is used to switch between high and low gain states by making use of the polarization dependent gain of Alexandrite. In gain-coefficient switched mode, the laser produces 85 ns pulses with a pulse energy of 240 mJ at a repetition rate of 5 Hz.

  2. Weight gain attitudes among pregnant adolescents.

    PubMed

    Stevens-Simon, C; Nakashima, I; Andrews, D

    1993-07-01

    Maternal weight gain is the most important, manageable determinant of infant birth weight among adolescents. Negative attitudes toward weight gain may adversely affect maternal weight gain. We hypothesized that (a) negative attitudes toward pregnancy weight gain are more common among younger pregnant adolescents, and (b) negative attitudes toward pregnancy weight gain adversely affect adolescent maternal weight gain. The study subjects, 99, radially diverse, pregnant 13 through 18 year olds, completed the 18-item, Likert-format, Pregnancy and Weight Gain Attitude Scale. Responses to the questionnaire indicated that most (83.8%) of the adolescents we interviewed had a positive attitude toward pregnancy weight gain when they entered prenatal care. Univariate analyses revealed that attitudes toward weight gain were unrelated to the respondents' ages but inversely related to their prepregnant weights (-0.16; p = 0.06) and the severity of their symptoms of depression (r = -0.26; p = 0.004). Attitudes toward weight gain were also directly related to their family support (r = 0.17; p = 0.06). Weight gain was significantly related to 4 of the 18 scale items but not to the total attitude scale score. We conclude that (a) the developmental task of formulating a positive body image does not foster more negative attitudes toward pregnancy weight gain among younger adolescents; (b) negative weight gain attitudes are most common among heavier adolescents, depressed adolescents, and adolescents who do not perceive their families as supportive; and (c) negative weight gain attitudes could adversely affect pregnancy weight gain.

  3. Consumption of low-fat dairy foods for 6 months improves insulin resistance without adversely affecting lipids or bodyweight in healthy adults: a randomized free-living cross-over study

    PubMed Central

    2013-01-01

    Background Given the highly debated role of dairy food consumption in modulating biomarkers of metabolic syndrome, this study was conducted to examine the influence of long-term (6 month) dairy consumption on metabolic parameters in healthy volunteers under free-living conditions without energy restriction. Methods Twenty-three healthy subjects completed a randomized, crossover trial of 12 months. Participants consumed their habitual diets and were randomly assigned to one of two treatment groups: a high dairy supplemented group instructed to consume 4 servings of dairy per day (HD); or a low dairy supplemented group limited to no more than 2 servings of dairy per day (LD). Baseline, midpoint, and endpoint metabolic responses were examined. Results Endpoint measurements of body weight and composition, energy expenditure, blood pressure, blood glucose, and blood lipid and lipoprotein responses did not differ (p > 0.05) between the LD and HD groups. HD consumption improved (p < 0.05) plasma insulin (-9%) and insulin resistance (-11%, p = 0.03) as estimated by HOMA-IR compared with the LD group. Conclusions Study results suggest that high dairy consumption (4 servings/d) may improve insulin resistance without negatively impacting bodyweight or lipid status under free-living conditions. Trial registration Trial registration: NCT01761955 PMID:23638799

  4. Information gains from cosmological probes

    NASA Astrophysics Data System (ADS)

    Grandis, S.; Seehars, S.; Refregier, A.; Amara, A.; Nicola, A.

    2016-05-01

    In light of the growing number of cosmological observations, it is important to develop versatile tools to quantify the constraining power and consistency of cosmological probes. Originally motivated from information theory, we use the relative entropy to compute the information gained by Bayesian updates in units of bits. This measure quantifies both the improvement in precision and the `surprise', i.e. the tension arising from shifts in central values. Our starting point is a WMAP9 prior which we update with observations of the distance ladder, supernovae (SNe), baryon acoustic oscillations (BAO), and weak lensing as well as the 2015 Planck release. We consider the parameters of the flat ΛCDM concordance model and some of its extensions which include curvature and Dark Energy equation of state parameter w. We find that, relative to WMAP9 and within these model spaces, the probes that have provided the greatest gains are Planck (10 bits), followed by BAO surveys (5.1 bits) and SNe experiments (3.1 bits). The other cosmological probes, including weak lensing (1.7 bits) and {H0} measures (1.7 bits), have contributed information but at a lower level. Furthermore, we do not find any significant surprise when updating the constraints of WMAP9 with any of the other experiments, meaning that they are consistent with WMAP9. However, when we choose Planck15 as the prior, we find that, accounting for the full multi-dimensionality of the parameter space, the weak lensing measurements of CFHTLenS produce a large surprise of 4.4 bits which is statistically significant at the 8 σ level. We discuss how the relative entropy provides a versatile and robust framework to compare cosmological probes in the context of current and future surveys.

  5. Effect of gastrointestinal nematode and liver fluke infections on weight gain and reproductive performance of beef heifers.

    PubMed

    Loyacano, A F; Williams, J C; Gurie, J; DeRosa, A A

    2002-08-02

    Spring born, crossbred beef heifers (n=372) were utilized over four years to measure reductions in body weights, reproductive performance and calf weights caused by gastrointestinal nematodes (primarily Ostertagia ostertagi) and the bovine liver fluke (Fasciola hepatica) and to differentiate losses attributable to each type of parasitism. Each year, weaned heifers were allotted to one of the four treatment regimens: Group 1, untreated controls; Group 2, treated for nematodes; Group 3, treated for liver fluke; and Group 4, treated for both nematodes and liver fluke. Nematodes were controlled with subcutaneous injections of either ivermectin (Ivomec, Merial) or doramectin (Dectomax, Pfizer), both at the recommended dose of 200 ug/kg bodyweight. Clorsulon (Curatrem, Merial) drench was given at the recommended rate of 7 mg/kg bodyweight to control flukes. Treatments and fecal collections were initiated at allotment each year and were repeated at 28-84-day intervals until palpation for pregnancy diagnosis. Open heifers were removed from the study at this time. Treatment dates were based on expected length of treatment efficacy, the stage of growth of the heifers and the seasonal risk of infection by the parasites. Pregnant females were pooled and received their assigned treatments prior to their calving and breeding seasons and remained together until their calves were weaned. Heifers treated for nematode infections were heavier and had higher condition scores (P<0.01) than untreated control heifers at initiation of breeding, and maintained that difference through pregnancy diagnosis. Liver fluke infection did not affect heifer gains or condition scores prior to palpation (P<0.01). At palpation, heifers treated for both forms of parasitism had the highest condition scores and weight gains (P<0.01), and also higher pregnancy rates than control heifers and heifers treated for nematodes only (P<0.01). Pregnancy rates for heifers treated for flukes only were not

  6. Review of High Gain FELs

    SciTech Connect

    Shintake, Tsumoru

    2007-01-19

    For understanding on basic radiation mechanism of the high-gain FEL based on SASE, the author presents electron-crystal interpretation of FEL radiation. In the electron-crystal, electrons are localized at regularly spaced multi-layers, which represents micro-bunching, whose spacing is equal to the radiation wavelength, and the multi-layers are perpendicular to beam axis, thus, diffracted wave creates Bragg's spots in forward and backward directions. Due to the Doppler's effect, frequency of the back-scattered wave is up-converted, generates forwardly focused X-ray. The Bragg's effect contributes focusing the X-ray beam into a spot, thus peak power becomes extremely higher by factor of typically 107. This is the FEL radiation. As well known, the total numbers of scattered photons in Bragg's spots is equal to the total elastic scattering photons from the atoms contained in the crystal. Therefore, total power in the FEL laser is same as the spontaneous radiation power from the undulator for the same beam parameter. The FEL radiation phenomenon is simple interference effect. In today's presentations, we use the laser pointer, and we frequently experience difficulty in pointing precisely or steadily in one place on the screen, since the laser spot is very small and does not spread. Exactly same to this, X-ray FEL is a highly focused beam, and pointing stability dominates productivity of experiment, thus we need special care on beam stability from linear accelerator.

  7. Factors influencing weight gain after renal transplantation.

    PubMed

    Johnson, C P; Gallagher-Lepak, S; Zhu, Y R; Porth, C; Kelber, S; Roza, A M; Adams, M B

    1993-10-01

    Weight gain following renal transplantation occurs frequently but has not been investigated quantitatively. A retrospective chart review of 115 adult renal transplant recipients was used to describe patterns of weight gain during the first 5 years after transplantation. Only 23 subjects (21%) were overweight before their transplant. Sixty-six subjects (57%) experienced a weight gain of greater than or equal to 10%, and 49 subjects (43%) were overweight according to Metropolitan relative weight criteria at 1 year after transplantation. There was an inverse correlation between advancing age and weight gain, with the youngest patients (18-29 years) having a 13.3% weight gain and the oldest patients (age greater than 50 years) having the lowest gain of 8.3% at 1 year (P = 0.047). Black recipients experienced a greater weight gain than whites during the first posttransplant year (14.6% vs. 9.0%; P = 0.043), and maintained or increased this difference over the 5-year period. Men and women experienced comparable weight gain during the first year (9.5% vs. 12.1%), but women continued to gain weight throughout the 5-year study (21.0% total weight gain). The men remained stable after the first year (10.8% total weight gain). Recipients who experienced at least a 10% weight gain also increased their serum cholesterol (mean 261 vs. 219) and triglyceride (mean 277 vs. 159) levels significantly, whereas those without weight gain did not. Weight gain did not correlate with cumulative steroid dose, donor source (living-related versus cadaver), rejection history, pre-existing obesity, the number of months on dialysis before transplantation, or posttransplant renal function. Posttransplant weight gain is related mainly to demographic factors, not to treatment factors associated with the transplant. The average weight gain during the first year after renal transplantation is approximately 10%. This increased weight, coupled with changes in lipid metabolism, may be significant in

  8. Nicotine Replacement: Effects on Postcessation Weight Gain.

    ERIC Educational Resources Information Center

    Gross, Janet; And Others

    1989-01-01

    Examined nicotine replacement effects on postcessation weight gain in smoking cessation volunteers. Randomly assigned abstinent subjects to active nicotine or placebo gum conditions for 10 weeks. Analyses revealed strong evidence for gum effect on weight gain, with active gum users gaining mean total of 3.8 pounds compared with 7.8 pounds for…

  9. Is Weight Gain after Smoking Cessation Inevitable?

    ERIC Educational Resources Information Center

    Talcott, Gerald W.; And Others

    1995-01-01

    Studied weight gain after smoking cessation in a naturalistic setting where all smokers quit and risk factors for postcessation weight gain were modified. Results showed no significant weight changes for smokers who quit. Suggests that an intensive program featuring dietary guidelines and increased physical activity can attenuate weight gain. (RJM)

  10. The association of subclinical hypocalcemia, negative energy balance and disease with bodyweight change during the first 30 days post-partum in dairy cows milked with automatic milking systems.

    PubMed

    Caixeta, L S; Ospina, P A; Capel, M B; Nydam, D V

    2015-05-01

    In a prospective cohort study, the daily bodyweight (BW) and milk production of 92 cows were recorded using automatic milking systems. The objectives were to characterize calcium serum concentration variability on days 1-3 post-partum and to evaluate the association between subclinical hypocalcemia (SHPC) and change in BW over the first 30 days in milk (DIM) in Holstein dairy cows, while controlling for concurrent disease and negative energy balance (NEB). SHPC was defined as total serum calcium concentration between 6 and 8 mg/dL, NEB was defined as non-esterified fatty acids (NEFA) > 0.7 mEq/L or β-hydroxybutyrate (BHB) ≥ 1.2 mmol/L. The peak incidence of SHPC was at 1 DIM for all groups (11%, 42% and 60% for parities 1, 2, and ≥3, respectively). All parity groups lost weight (21, 33, and 34 kg) during the first 30 DIM. Parity 1 animals with disease compared with those without disease lost the most weight (2.6 kg/day BW loss vs. <1.9 kg/day, respectively). Normocalcemic parity 2 animals with either NEB or disease lost the most weight (>5 kg/day) compared with those in the SHPC group (≤4.5 kg/day). In parity ≥ 3 animals, SHPC was an important factor for BW loss; SHPC animals lost the most weight (>3.7 kg/day) vs. normocalcemic cows (≤3.3 kg/day) regardless of NEB or disease status. Even though all animals lost weight during early lactation the effect of disease, NEB, and SHPC on BW loss was different in each parity group.

  11. Combination of the sodium-glucose cotransporter-2 inhibitor empagliflozin with orlistat or sibutramine further improves the body-weight reduction and glucose homeostasis of obese rats fed a cafeteria diet.

    PubMed

    Vickers, Steven P; Cheetham, Sharon C; Headland, Katie R; Dickinson, Keith; Grempler, Rolf; Mayoux, Eric; Mark, Michael; Klein, Thomas

    2014-01-01

    The present study assessed the potential of the sodium glucose-linked transporter (SGLT)-2 inhibitor empagliflozin to decrease body weight when administered alone or in combination with the clinically effective weight-loss agents orlistat and sibutramine in obese rats fed a cafeteria diet. Female Wistar rats were exposed to a cafeteria diet to induce obesity. Empagliflozin was dosed once daily (10, 30, and 60 mg/kg) for 28 days. Combination studies were subsequently performed using a submaximal empagliflozin dose (10 mg/kg) with either sibutramine or orlistat. Body weight, food, and water intake were recorded daily. The effect of drug treatment on glucose tolerance, relevant plasma parameters, and carcass composition was determined. Empagliflozin dose-dependently reduced body weight, plasma leptin, and body fat though increased urinary glucose excretion. The combination of empagliflozin and orlistat significantly reduced body weight compared to animals treated with either drug alone, and significantly improved glucose tolerance, plasma insulin, and leptin compared to vehicle-treated controls. The effect of sibutramine to improve glycemic control in an oral glucose-tolerance test was also significantly increased, with empagliflozin and combination treatment leading to a reduction in carcass fat greater than that observed with either drug alone. These data demonstrate that empagliflozin reduces body weight in cafeteria-fed obese rats. In combination studies, empagliflozin further improved the body-weight or body-fat loss of animals in comparison to orlistat or sibutramine alone. Such studies may indicate improved strategies for the treatment of obese patients with prediabetes or type 2 diabetes.

  12. Combination of the sodium-glucose cotransporter-2 inhibitor empagliflozin with orlistat or sibutramine further improves the body-weight reduction and glucose homeostasis of obese rats fed a cafeteria diet

    PubMed Central

    Vickers, Steven P; Cheetham, Sharon C; Headland, Katie R; Dickinson, Keith; Grempler, Rolf; Mayoux, Eric; Mark, Michael; Klein, Thomas

    2014-01-01

    The present study assessed the potential of the sodium glucose-linked transporter (SGLT)-2 inhibitor empagliflozin to decrease body weight when administered alone or in combination with the clinically effective weight-loss agents orlistat and sibutramine in obese rats fed a cafeteria diet. Female Wistar rats were exposed to a cafeteria diet to induce obesity. Empagliflozin was dosed once daily (10, 30, and 60 mg/kg) for 28 days. Combination studies were subsequently performed using a submaximal empagliflozin dose (10 mg/kg) with either sibutramine or orlistat. Body weight, food, and water intake were recorded daily. The effect of drug treatment on glucose tolerance, relevant plasma parameters, and carcass composition was determined. Empagliflozin dose-dependently reduced body weight, plasma leptin, and body fat though increased urinary glucose excretion. The combination of empagliflozin and orlistat significantly reduced body weight compared to animals treated with either drug alone, and significantly improved glucose tolerance, plasma insulin, and leptin compared to vehicle-treated controls. The effect of sibutramine to improve glycemic control in an oral glucose-tolerance test was also significantly increased, with empagliflozin and combination treatment leading to a reduction in carcass fat greater than that observed with either drug alone. These data demonstrate that empagliflozin reduces body weight in cafeteria-fed obese rats. In combination studies, empagliflozin further improved the body-weight or body-fat loss of animals in comparison to orlistat or sibutramine alone. Such studies may indicate improved strategies for the treatment of obese patients with prediabetes or type 2 diabetes. PMID:25061325

  13. BDNF: no gain without pain?

    PubMed

    Smith, Peter A

    2014-12-26

    Injury to the adult nervous system promotes the expression and secretion of brain-derived neurotrophic factor (BDNF). Because it promotes neuronal growth, survival and neurogenesis, BDNF may initiate compensatory processes that mitigate the deleterious effects of injury, disease or stress. Despite this, BDNF has been implicated in several injury-induced maladaptive processes including pain, spasticity and convulsive activity. This review will concentrate on the predominant role of BDNF in the initiation and maintenance of chronic and/or neuropathic pain at the spinal, peripheral and central levels. Within the spinal dorsal horn, the pattern of BDNF-induced changes in synaptic transmission across five different, identified neuronal phenotypes bears a striking resemblance to that produced by chronic constriction injury (CCI) of peripheral nerves. The appearance of this "pain footprint" thus reflects multiple sensitizing actions of microglial-derived BDNF. These include changes in the chloride equilibrium potential, decreased excitatory synaptic drive to inhibitory neurons, complex changes in inhibitory (GABA/glycinergic) synaptic transmission, increases in excitatory synaptic drive to excitatory neurons and the appearance of oscillatory activity. BDNF effects are confined to changes in synaptic transmission as there is little change in the passive or active properties of neurons in the superficial dorsal horn. Actions of BDNF in the brain stem and periphery also contribute to the onset and persistence of chronic pain. In spite of its role in compensatory processes that facilitate the recovery of the nervous system from injury, the widespread maladaptive actions of BDNF mean that there is literally "no gain without pain".

  14. Gestational weight gain among Hispanic women.

    PubMed

    Sangi-Haghpeykar, Haleh; Lam, Kim; Raine, Susan P

    2014-01-01

    To describe gestational weight gain among Hispanic women and to examine psychological, social, and cultural contexts affecting weight gain. A total of 282 Hispanic women were surveyed post-partum before leaving the hospital. Women were queried about their prepregnancy weight and weight gained during pregnancy. Adequacy of gestational weight gain was based on guidelines set by the Institute of Medicine in 2009. Independent risk factors for excessive or insufficient weight gain were examined by logistic regression. Most women were unmarried (59 %), with a mean age of 28.4 ± 6.6 years and an average weight gain of 27.9 ± 13.3 lbs. Approximately 45 % of women had gained too much, 32 % too little, and only 24 % had an adequate amount of weight gain. The mean birth weight was 7.3, 7.9, and 6.8 lbs among the adequate, excessive, and insufficient weight gain groups. Among women who exercised before pregnancy, two-thirds continued to do so during pregnancy; the mean gestational weight gain of those who continued was lower than those who stopped (26.8 vs. 31.4 lbs, p = 0.04). Independent risk factors for excessive weight gain were being unmarried, U.S. born, higher prepregnancy body mass index, and having indifferent or negative views about weight gain. Independent risk factors for insufficient weight gain were low levels of support and late initiation of prenatal care. Depression, stress, and a woman's or her partner's happiness regarding pregnancy were unrelated to weight gain. The results of this study can be used by prenatal programs to identify Hispanic women at risk for excessive or insufficient gestational weight gain.

  15. Controlling gain one photon at a time.

    PubMed

    Schwartz, Gregory W; Rieke, Fred

    2013-05-14

    Adaptation is a salient property of sensory processing. All adaptational or gain control mechanisms face the challenge of obtaining a reliable estimate of the property of the input to be adapted to and obtaining this estimate sufficiently rapidly to be useful. Here, we explore how the primate retina balances the need to change gain rapidly and reliably when photons arrive rarely at individual rod photoreceptors. We find that the weakest backgrounds that decrease the gain of the retinal output signals are similar to those that increase human behavioral threshold, and identify a novel site of gain control in the retinal circuitry. Thus, surprisingly, the gain of retinal signals begins to decrease essentially as soon as background lights are detectable; under these conditions, gain control does not rely on a highly averaged estimate of the photon count, but instead signals from individual photon absorptions trigger changes in gain. DOI:http://dx.doi.org/10.7554/eLife.00467.001.

  16. Environmentally Enriched Male Mink Gain More Copulations than Stereotypic, Barren-Reared Competitors

    PubMed Central

    Díez-León, María; Bowman, Jeff; Bursian, Steve; Filion, Hélène; Galicia, David; Kanefsky, Jeannette; Napolitano, Angelo; Palme, Rupert; Schulte-Hostedde, Albrecht; Scribner, Kim; Mason, Georgia

    2013-01-01

    Wild carnivores in zoos, conservation breeding centres, and farms commonly live in relatively small, unstimulating enclosures. Under these captive conditions, in a range of species including giant pandas, black-footed ferrets, and European mink, male reproductive abilities are often poor. Such problems have long been hypothesized to be caused by these animals' housing conditions. We show for the first time that rearing under welfare-improving (i.e., highly valued and stress-reducing) environmental enrichments enhances male carnivores' copulatory performance: in mate choice competitions, enriched male American mink (Neovison vison) mated more often than non-enriched males. We screened for several potential mediators of this effect. First was physiological stress and its impact on reproductive physiology; second, stress-mediated changes in morphology and variables related to immunocompetence that could influence male attractiveness; and third, behavioural changes likely to affect social competence, particularly autistic-like excessive routine and repetition (‘perseveration’) as is reflected in the stereotypies common in captive animals. Consistent with physiological stress, excreted steroid metabolites revealed that non-enriched males had higher cortisol levels and lower androgen levels than enriched conspecifics. Their os penises (bacula) also tended to be less developed. Consistent with reduced attractiveness, non-enriched males were lighter, with comparatively small spleens and a trend to greater fluctuating asymmetry. Consistent with impaired social competence, non-enriched males performed more stereotypic behaviour (e.g., pacing) in their home cages. Of all these effects, the only significant predictor of copulation number was stereotypy (a trend suggesting that low bodyweights may also be influential): highly stereotypic males gained the fewest copulations. The neurophysiological changes underlying stereotypy thus handicap males sexually. We hypothesise

  17. Transient gain analysis of gain-switched semiconductor lasers during pulse lasing.

    PubMed

    Chen, Shaoqiang; Ito, Takashi; Asahara, Akifumi; Nakamae, Hidekazu; Nakamura, Takahiro; Yoshita, Masahiro; Kim, Changsu; Zhang, Baoping; Yokoyama, Hiroyuki; Suemoto, Tohru; Akiyama, Hidefumi

    2015-12-10

    We analyzed the transient gain properties of three gain-switched semiconductor lasers with different materials and cavity structures during pulse lasing. All the semiconductor lasers were pumped with impulse optical pumping, and all the generated gain-switched output pulses were well described by exponential functions in their rise parts, wherein the transient gains were derived according to the rate-equation theoretical model. In spite of the different laser structures and materials, the results consistently demonstrated that a higher transient gain produces shorter output pulses, indicating the dominant role of higher transient gain in the generation of even shorter gain-switched pulses with semiconductor lasers.

  18. Microchannel plate modal gain variations with temperature

    NASA Technical Reports Server (NTRS)

    Slater, David C.; Timothy, J. G.

    1993-01-01

    Measurements of the modal gain of two high-gain curved-channel microchannel plates (MCPs) at various operating temperatures are presented. Both MCPs were fabricated from the Long Life glass with 12-micron diam channels on 15-micron centers. The modal gain was found to decrease with increasing temperature at a rate of -0.1 percent C. This reduction of gain with temperature is attributed primarily to an axial temperature gradient along each MCP channel creating a nonuniform electric field within the channel that lowers the effective output gain. A lowering of the secondary electron yield resulting from increased phonon scattering of secondary electrons released within the walls of the MCP channels was assessed, but was found to have a negligible contribution to the drop in gain with temperature.

  19. Optical antenna gain. I - Transmitting antennas

    NASA Technical Reports Server (NTRS)

    Klein, B. J.; Degnan, J. J.

    1974-01-01

    The gain of centrally obscured optical transmitting antennas is analyzed in detail. The calculations, resulting in near- and far-field antenna gain patterns, assume a circular antenna illuminated by a laser operating in the TEM-00 mode. A simple polynomial equation is derived for matching the incident source distribution to a general antenna configuration for maximum on-axis gain. An interpretation of the resultant gain curves allows a number of auxiliary design curves to be drawn that display the losses in antenna gain due to pointing errors and the cone angle of the beam in the far field as a function of antenna aperture size and its central obscuration. The results are presented in a series of graphs that allow the rapid and accurate evaluation of the antenna gain which may then be substituted into the conventional range equation.

  20. Optical antenna gain. 1: transmitting antennas.

    PubMed

    Klein, B J; Degnan, J J

    1974-09-01

    The gain of centrally obscured optical transmitting antennas is analyzed in detail. The calculations, resulting in near- and far-field antenna gain patterns, assume a circular antenna illuminated by a laser operating in the TEM(00) mode. A simple polynomial equation is derived for matching the incident source distribution to a general antenna configuration for maximum on-axis gain. An interpretation of the resultant gain curves allows a number of auxiliary design curves to be drawn that display the losses in antenna gain due to pointing errors and the cone angle of the beam in the far field as a function of antenna aperture size and its central obscuration. The results are presented in a series of graphs that allow the rapid and accurate evaluation of the antenna gain which may then be substituted into the conventional range equation.

  1. Gestational weight gain trajectories in primary care

    PubMed Central

    Piccinini-Vallis, Helena; Lee-Baggley, Dayna; Stewart, Moira; Ryan, Bridget

    2016-01-01

    Objective To identify gestational weight gain trajectories, stratified by prepregnancy body mass index (BMI), of women with singleton pregnancies who received prenatal care in a primary care setting, and to compare these trajectories with the 2009 Institute of Medicine gestational weight gain recommendations. Design Retrospective cohort study. Setting Halifax, NS. Participants Women who received prenatal care at the Dalhousie Family Medicine clinics in Halifax from 2009 to 2013. Main outcome measures For each prenatal visit, gestational age and weight measurements were obtained. Multilevel modeling was used to analyze the gestational weight gain trajectories. The upper limit of the guideline-recommended weekly gestational weight gain was compared with the 95% CI of the observed mean weekly gestational weight gain for each prepregnancy BMI category. Results A total of 280 women were included in the analyses. There was a significant interaction between prepregnancy BMI category and gestational weight gain over time (P < .001), with gestational weight gain being significantly lower among women with prepregnancy BMI of 30.0 kg/m2 or greater compared with those with BMI of 18.5 to less than 25.0 kg/m2 and 25.0 to less than 30.0 kg/m2. When comparing women’s weight gain with the recommendations, women with prepregnancy BMI of 25.0 to less than 30.0 kg/m2 had the most guideline discordance, deviating from the weight gain recommendations at 20 weeks’ gestation. Conclusion These results are relevant and of benefit to women and clinicians wishing to address excess gestational weight gain, and to researchers and policy makers developing interventions aimed at curbing gestational weight gain in primary care. Although our results showed women with prepregnancy BMI of 25.0 to less than 30.0 kg/m2 gained the most excess, guideline-discordant weight, interventions should target all women planning or experiencing a pregnancy.

  2. Unstable resonators with a distributed focusing gain.

    PubMed

    Ferguson, T R

    1994-08-20

    The geometrical optics approximation is used to form a model of axisymmetric unstable resonators having distributed focus, gain, and loss. A tapered reflectivity feedback mirror is included. The rate equations for propagation through the focusing gain medium are derived. A unique grid is found for propagation without interpolation along eigenrays in each direction. Numerical examples show the effects of distributed gain and focus on the axial and transverse intensity distributions.

  3. Measurement of Antenna Bore-Sight Gain

    NASA Technical Reports Server (NTRS)

    Fortinberry, Jarrod; Shumpert, Thomas H.

    2016-01-01

    The absolute or free-field gain of a simple antenna can be approximated using standard antenna theory formulae or for a more accurate prediction, numerical methods may be employed to solve for antenna parameters including gain. Both of these methods will result in relatively reasonable estimates but in practice antenna gain is usually verified and documented via measurements and calibration. In this paper, a relatively simple and low-cost, yet effective means of determining the bore-sight free-field gain of a VHF/UHF antenna is proposed by using the Brewster angle relationship.

  4. Error margin for antenna gain measurements

    NASA Technical Reports Server (NTRS)

    Cable, V.

    2002-01-01

    The specification of measured antenna gain is incomplete without knowing the error of the measurement. Also, unless gain is measured many times for a single antenna or over many identical antennas, the uncertainty or error in a single measurement is only an estimate. In this paper, we will examine in detail a typical error budget for common antenna gain measurements. We will also compute the gain uncertainty for a specific UHF horn test that was recently performed on the Jet Propulsion Laboratory (JPL) antenna range. The paper concludes with comments on these results and how they compare with the 'unofficial' JPL range standard of +/- ?.

  5. Correcting the Normalized Gain for Guessing

    ERIC Educational Resources Information Center

    Stewart, John; Stewart, Gay

    2010-01-01

    The normalized gain, "g", has been an important tool for the characterization of conceptual improvement in physics courses since its use in Hake's extensive study on conceptual learning in introductory physics. The normalized gain is calculated from the score on a pre-test administered before instruction and a post-test administered…

  6. Gain Shift Corrections at Chi-Nu

    SciTech Connect

    Brown, Tristan Brooks; Devlin, Matthew James

    2016-08-30

    Ambient conditions have the potential to cause changes in liquid scintillator detector gain that vary with time and temperature. These gain shifts can lead to poor resolution in both energy as well as pulse shape discrimination. In order to correct for these shifts in the Chi-Nu high energy array, a laser system has been developed for calibration of the pulse height signals.

  7. 75 FR 43615 - Program Integrity: Gainful Employment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-26

    ... Education 34 CFR Part 668 Program Integrity: Gainful Employment; Proposed Rule #0;#0;Federal Register / Vol... RIN 1840-AD04 Program Integrity: Gainful Employment AGENCY: Office of Postsecondary Education... against the education and training (and increased employment income) that higher education can provide....

  8. Physical and psychological consequences of weight gain.

    PubMed

    Kawachi, I

    1999-01-01

    Obesity and overweight are clearly associated with many serious conditions, including type II diabetes mellitus, hypertension, and coronary heart disease. Excess weight also increases the risk of death. Recent evidence suggests that weight gain itself, even if persons remain within the "normal" weight range, also increases the risk of medical illnesses and premature death. Persons who gain 5.0 to 7.9 kg (11 to 17.3 lb) as adults are 1.9 times more likely to develop type II diabetes mellitus and 1.25 times more likely to develop coronary heart disease than those who lose weight or maintain a stable weight after age 18 years. Gaining 11 to 20 kg (24.2 to 44 lb) or more in adulthood increases the risk of ischemic stroke 1.69 to 2.52 times. The relationship between weight gain and breast cancer has been difficult to study, primarily because postmenopausal hormone replacement therapy can mask the effect of weight gain on cancer risk. Accordingly, weight gain in adulthood has been associated with an increased risk of breast cancer only among women who have never used hormone replacement therapy. In addition to its adverse effects on disease outcomes, weight gain also impairs physical functioning, reduces quality of life, and is associated with poor mental health. These psychological and mental health consequences of weight gain can become an added burden for patients with schizophrenia and other mental disorders.

  9. Complying with physician gain-sharing restrictions.

    PubMed

    O'Hare, P K

    1998-05-01

    Many IDSs are considering implementing gain-sharing programs as a way to motivate their physicians to provide high-quality, cost-effective services. Before embarking on such programs, however, IDSs need to understand the legal requirements associated with such programs to ensure that the gain-sharing arrangement is in compliance with Federal law.

  10. GaInNAs laser gain

    SciTech Connect

    CHOW,WENG W.; JONES,ERIC D.; MODINE,NORMAND A.; KURTZ,STEVEN R.; ALLERMAN,ANDREW A.

    2000-05-23

    The optical gain spectra for GaInNAs/GaAs quantum wells are computed using a microscopic laser theory. From these spectra, the peak gain and carrier radiative decay rate as functions of carrier density are determined. These dependences allow the study of the lasing threshold current density of GaInNAs/GaAs quantum well structures.

  11. Sudden Gains During Therapy of Social Phobia

    PubMed Central

    Hofmann, Stefan G.; Schulz, Stefan M.; Meuret, Alicia E.; Moscovitch, David A.; Suvak, Michael

    2007-01-01

    The present study investigated the phenomenon of sudden gains in 107 participants with social phobia (social anxiety disorder) who received either cognitive–behavioral group therapy or exposure group therapy without explicit cognitive interventions, which primarily used public speaking situations as exposure tasks. Twenty-two out of 967 session-to-session intervals met criteria for sudden gains, which most frequently occurred in Session 5. Individuals with sudden gains showed similar improvements in the 2 treatment groups. Although cognitive–behavioral therapy was associated with more cognitive changes than exposure therapy, cognitive changes did not precede sudden gains. In general, the results of this study question the clinical significance of sudden gains in social phobia treatment. PMID:16881776

  12. The effect of a fenbendazole treatment on cyst excretion and weight gain in calves experimentally infected with Giardia duodenalis.

    PubMed

    Geurden, Thomas; Vandenhoute, Els; Pohle, Herbert; Casaert, Stijn; De Wilde, Nathalie; Vercruysse, Jozef; Claerebout, Edwin

    2010-04-19

    A total of 28 Holstein-Friesian calves were experimentally infected with 10(5)Giardia duodenalis cysts. Eleven days later, all animals were allocated into two groups of 14 animals each, based on the average pre-treatment cyst counts. Treatment was randomly assigned to one of the two groups, and all animals in the treatment group received a daily oral dosage of 15mg fenbendazole per kg bodyweight during 3 consecutive days. The calves in the control group received a placebo (water). From 3 days after treatment onwards, cyst excretion was determined three times a week during 4 consecutive weeks. The faecal consistency and general health were recorded on a daily basis, and all animals were weighed prior to treatment and weekly thereafter. At the end of the experimental period, there was a significant (P<0.001) reduction (98%) of the cumulative cyst excretion. There were no significant differences in general health between both groups, but faecal consistency was significantly lower (P<0.002) in the control group compared to the treatment group, although none of the animals displayed overt gastro-intestinal symptoms. Prior to treatment the weight did not differ between both experimental groups. At the end of the 4-week experimental period however, the animals in the treatment group gained on average 2.86kg (=102g per day) more than the animals in the control group (P<0.031). This study demonstrates for the first time a significant difference in weight gain between fenbendazole treated and untreated calves experimentally infected with G. duodenalis, although additional data need to confirm the need for treatment in natural conditions.

  13. TCAD simulation of Low Gain Avalanche Detectors

    NASA Astrophysics Data System (ADS)

    Dalal, Ranjeet; Jain, Geetika; Bhardwaj, Ashutosh; Ranjan, Kirti

    2016-11-01

    In the present work, detailed simulation using Technology Computer Aided Design (TCAD) tool, Silvaco for non-irradiated and irradiated LGAD (Low Gain Avalanche Detector) devices has been carried out. The effects of different design parameters and proton irradiation on LGAD operation are discussed in detail. An already published effective two trap bulk damage model is used to simulate the radiation damage without implementing any acceptor removal term. The TCAD simulation for irradiated LGAD devices produce decreasing gain with increasing fluence, similar to the measurement results. The space charge density and electric field distribution are used to illustrate the possible reasons for the degradation of gain of the irradiated LGAD devices.

  14. Nonunity gain minimal-disturbance measurement

    SciTech Connect

    Sabuncu, Metin; Andersen, Ulrik L.; Mista, Ladislav Jr.; Fiurasek, Jaromir; Filip, Radim; Leuchs, Gerd

    2007-09-15

    We propose and experimentally demonstrate an optimal nonunity gain Gaussian scheme for partial measurement of an unknown coherent state that causes minimal disturbance of the state. The information gain and the state disturbance are quantified by the noise added to the measurement outcomes and to the output state, respectively. We derive the optimal trade-off relation between the two noises and we show that the tradeoff is saturated by nonunity gain teleportation. Optimal partial measurement is demonstrated experimentally using a linear optics scheme with feedforward.

  15. Frequency Dependence of APATS Antenna Gain

    DTIC Science & Technology

    1982-03-01

    ESD-TR-82-120 HTR-8354 3FREQUENCY DEPENDENCE OF APATS ANTENNA GAIN 0 By G. A. ROBERTSHAW MARCH 1982 Prepared for DEPUTY FOR SURVEILLANCE AND CONTROL...FREQUENCY DEPENDENCE OF APATS ANTENNA GAIN 6. PERFORMING ORG. REPORT NUMBER MTR-8354 7. AUTHOR(*) S. CONTRACT OR GRANT NUMBER(s) G. A. ROBERTSHAW F19628-81-C...employed, each channel will lose 1.76 dB of gain. * E.g., if "a" is aperture length in array azimuth plane, frequency dependence begins for 0 > srFl

  16. Optical properties of nanowire metamaterials with gain

    NASA Astrophysics Data System (ADS)

    Lima, Joaquim; Adam, Jost; Rego, Davi; Esquerre, Vitaly; Bordo, Vladimir

    2016-11-01

    The transmittance, reflectance and absorption of a nanowire metamaterial with optical gain are numerically simulated and investigated. It is assumed that the metamaterial is represented by aligned silver nanowires embedded into a semiconductor matrix, made of either silicon or gallium phosphide. The gain in the matrix is modeled by adding a negative imaginary part to the dielectric function of the semiconductor. It is found that the optical coefficients of the metamaterial depend on the gain magnitude in a non-trivial way: they can both increase and decrease with gain depending on the lattice constant of the metamaterial. This peculiar behavior is explained by the field redistribution between the lossy metal nanowires and the amplifying matrix material. These findings are significant for a proper design of nanowire metamaterials with low optical losses for diverse applications.

  17. Experience matters: information acquisition optimizes probability gain.

    PubMed

    Nelson, Jonathan D; McKenzie, Craig R M; Cottrell, Garrison W; Sejnowski, Terrence J

    2010-07-01

    Deciding which piece of information to acquire or attend to is fundamental to perception, categorization, medical diagnosis, and scientific inference. Four statistical theories of the value of information-information gain, Kullback-Liebler distance, probability gain (error minimization), and impact-are equally consistent with extant data on human information acquisition. Three experiments, designed via computer optimization to be maximally informative, tested which of these theories best describes human information search. Experiment 1, which used natural sampling and experience-based learning to convey environmental probabilities, found that probability gain explained subjects' information search better than the other statistical theories or the probability-of-certainty heuristic. Experiments 1 and 2 found that subjects behaved differently when the standard method of verbally presented summary statistics (rather than experience-based learning) was used to convey environmental probabilities. Experiment 3 found that subjects' preference for probability gain is robust, suggesting that the other models contribute little to subjects' search behavior.

  18. Can Beta Blockers Cause Weight Gain?

    MedlinePlus

    Diseases and Conditions High blood pressure (hypertension) Can beta blockers cause weight gain? Answers from Sheldon G. Sheps, ... can occur as a side effect of some beta blockers, especially the older ones, such as atenolol (Tenormin) ...

  19. Tradeoff on gain-flatness and gain-stabilization of erbium doped fiber amplifier with FBGs

    NASA Astrophysics Data System (ADS)

    Buyin, Garidi; OuYang, Yunlun; Ma, Yu; Chang, Jinlong; Liu, Changxing; Yang, Jiuru

    2014-07-01

    It is a challenge to get gain-stabilization and gain-flatness of erbium doped fiber amplifier (EDFA) in C-band, simultaneously. In this article, we establish a gain-clamped EDFA model based uniform fiber grating-pair and optimize the reflectivity of grating by the designed targets. The tradeoff between stabilization and flatness can be obtained when an ideal reflectivity is adopted. The numerical results show that the gain-stabilization is controlled in +/-0.1dB and gain-flatness is less than +/-1.41dB in the range from 1535nm to 1565nm.

  20. 34 CFR 462.43 - How is educational gain measured?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Educational Gain? § 462.43 How is educational gain measured? (a)(1) Educational gain is measured by comparing... educational functioning level. To measure educational gain, the local eligible provider would compare...

  1. Central Gain Control in Tinnitus and Hyperacusis

    PubMed Central

    Auerbach, Benjamin D.; Rodrigues, Paulo V.; Salvi, Richard J.

    2014-01-01

    Sensorineural hearing loss induced by noise or ototoxic drug exposure reduces the neural activity transmitted from the cochlea to the central auditory system. Despite a reduced cochlear output, neural activity from more central auditory structures is paradoxically enhanced at suprathreshold intensities. This compensatory increase in the central auditory activity in response to the loss of sensory input is referred to as central gain enhancement. Enhanced central gain is hypothesized to be a potential mechanism that gives rise to hyperacusis and tinnitus, two debilitating auditory perceptual disorders that afflict millions of individuals. This review will examine the evidence for gain enhancement in the central auditory system in response to cochlear damage. Further, it will address the potential cellular and molecular mechanisms underlying this enhancement and discuss the contribution of central gain enhancement to tinnitus and hyperacusis. Current evidence suggests that multiple mechanisms with distinct temporal and spectral profiles are likely to contribute to central gain enhancement. Dissecting the contributions of these different mechanisms at different levels of the central auditory system is essential for elucidating the role of central gain enhancement in tinnitus and hyperacusis and, most importantly, the development of novel treatments for these disorders. PMID:25386157

  2. FEL gain optimisation and spontaneous radiation

    SciTech Connect

    Bali, L.M.; Srivastava, A.; Pandya, T.P.

    1995-12-31

    Colson have evaluated FEL gains for small deviations from perfect electron beam injection, with radiation of the same polarisation as that of the wiggler fields. We find that for optimum gain the polarisation of the optical field should be the same as that of the spontaneous emission under these conditions. With a helical wiggler the axial oscillations resulting from small departures from perfect electron beam injection lead to injection dependent unequal amplitudes and phases of the spontaneous radiation in the two transverse directions. Viewed along the axis therefore the spontaneous emission is elliptically polarised. The azimuth of the ellipse varies with the difference of phase of the two transverse components of spontaneous emission but the eccentricity remains the same. With planar wigglers the spontaneous emission viewed in the axial direction is linearly polarised, again with an injection dependent azimuth. For optimum coherent gain of a radiation field its polarisation characteristics must be the same as those of the spontaneous radiation with both types of wiggler. Thus, with a helical wiggler and the data reported earlier, an increase of 10% in the FEL gain at the fundamental frequency and of 11% at the fifth harmonic has been calculated in the small gain per pass limit. Larger enhancements in gain may result from more favourable values of input parameters.

  3. Context-specific adaptation of saccade gain

    NASA Technical Reports Server (NTRS)

    Shelhamer, Mark; Clendaniel, Richard A.

    2002-01-01

    Previous studies established that vestibular reflexes can have two adapted states (e.g., gain) simultaneously, and that a context cue (e.g., vertical eye position) can switch between the two states. The present study examined this phenomenon of context-specific adaptationfor horizontal saccades, using a variety of contexts. Our overall goal was to assess the efficacy of different context cues in switching between adapted states. A standard double-step paradigm was used to adapt saccade gain. In each experiment, we asked for a simultaneous gain decrease in one context and gain increase in another context, and then determined if a change in the context would invoke switching between the adapted states. Horizontal eye position worked well as a context cue: saccades with the eyes deviated to the right could be made to have higher gains while saccades with the eyes deviated to the left could be made to have lower gains. Vertical eye position was less effective. This suggests that the more closely related a context cue is to the response being adapted, the more effective it is. Roll tilt of the head, and upright versus supine orientations, were somewhat effective in context switching; these paradigms contain orientation of gravity with respect to the head as part of the context.

  4. Determination of the STIS CCD Gain

    NASA Astrophysics Data System (ADS)

    Riley, Allyssa; Monroe, TalaWanda R.; Lockwood, Sean A.

    2017-01-01

    The Space Telescope Imaging Spectrograph (STIS) has been aboard the Hubble Space Telescope (HST) for almost 20 years. The STIS instrument team at Space Telescope Science Institute has continuously endeavored to provide high quality scientific data to the astronomical community, in part by monitoring the health and stability of the instrument. Because the change in gain value over time is a proxy for detector health, we measured the gain of the STIS CCD for amplifiers A, C and D using the mean-variance method, which has not been used to measure the CCD gain on STIS since before it was installed on HST. Here we present our methodology and results using data from the HST program 14424, which indicate a <3.5% change in the gain for amplifier D from when it was originally calculated pre-flight. We compare the various CCD gain measurements made over the history of STIS and discuss the extent to which the data and the different measurement techniques allow real changes to be distinguished from small systematic measurement errors. For the time being, we recommend the continued use of the currently adopted calibration pipeline values of 1.000 and 4.016 e-/DN for amplifier D at the nominal gain settings 1 and 4 e-/DN, respectively, as these are the values that were adopted when determining the other instrument calibrations.

  5. Astrovirus, reovirus and rotavirus concomitant infection causes decreased weight gain in broad-breasted white poults

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Turkey astrovirus type-2 (TAstV-2), turkey rotavirus (TRotV) and turkey reovirus (TReoV) were evaluated for pathogenesis in 3 day-old turkey poults in all possible combinations of one, two or three viruses. Body-weights were recorded at 2, 4, 7, 10 and 14 days post inoculation (PI) and were decreas...

  6. Edemagenic gain and interstitial fluid volume regulation.

    PubMed

    Dongaonkar, R M; Quick, C M; Stewart, R H; Drake, R E; Cox, C S; Laine, G A

    2008-02-01

    Under physiological conditions, interstitial fluid volume is tightly regulated by balancing microvascular filtration and lymphatic return to the central venous circulation. Even though microvascular filtration and lymphatic return are governed by conservation of mass, their interaction can result in exceedingly complex behavior. Without making simplifying assumptions, investigators must solve the fluid balance equations numerically, which limits the generality of the results. We thus made critical simplifying assumptions to develop a simple solution to the standard fluid balance equations that is expressed as an algebraic formula. Using a classical approach to describe systems with negative feedback, we formulated our solution as a "gain" relating the change in interstitial fluid volume to a change in effective microvascular driving pressure. The resulting "edemagenic gain" is a function of microvascular filtration coefficient (K(f)), effective lymphatic resistance (R(L)), and interstitial compliance (C). This formulation suggests two types of gain: "multivariate" dependent on C, R(L), and K(f), and "compliance-dominated" approximately equal to C. The latter forms a basis of a novel method to estimate C without measuring interstitial fluid pressure. Data from ovine experiments illustrate how edemagenic gain is altered with pulmonary edema induced by venous hypertension, histamine, and endotoxin. Reformulation of the classical equations governing fluid balance in terms of edemagenic gain thus yields new insight into the factors affecting an organ's susceptibility to edema.

  7. CONDITIONS FOR CSR MICROBUNCHING GAIN SUPPRESSION

    SciTech Connect

    Tsai, Cheng Ying; Douglas, David R.; Li, Rui; Tennant, Christopher D.; di Mitri, Simone

    2016-05-01

    The coherent synchrotron radiation (CSR) of a high brightness electron beam traversing a series of dipoles, such as transport arcs, may result in phase space degradation. On one hand, the CSR can perturb electron transverse motion in dispersive regions along the beamline, causing emittance growth. On the other hand, the CSR effect on the longitudinal beam dynamics could result in microbunching gain enhancement. For transport arcs, several schemes have been proposed* to suppress the CSR-induced emittance growth. Similarly, several scenarios have been introduced** to suppress CSR-induced microbunching gain, which however mostly aim for linac-based machines. In this paper we try to provide sufficient conditions for suppression of CSR-induced microbunching gain along a transport arc, analogous to*. Several example lattices are presented, with the relevant microbunching analyses carried out by our semi-analytical Vlasov solver***. The simulation results show that lattices satisfying the proposed conditions indeed have microbunching gain suppressed. We expect this analysis can shed light on lattice design approach that could suppress the CSR-induced microbunching gain.

  8. Gain and energy storage in holmium YLF

    NASA Technical Reports Server (NTRS)

    Storm, Mark E.; Deyst, John P.

    1991-01-01

    It is demonstrated that Q-switched holmium lasers are capable of high-gain and high-energy operation at 300 K. Small-signal gain coefficients of 0.50 and 0.12/cm have been measured in YLF and YAG, respectively. Small-signal gains of 0.50/cm are comparable to those achievable in Nd:YAG and are not typical of low-gain materials. This large gain in the Ho:YLF material is made possible by operating the amplifier in the ground state depletion mode. The amplifier performance data and associated analysis presented demonstrate that efficient energy storage is possible with very high excited state ion densities of the Ho 5I7 upper laser level. This is an important result since upconversion can limit the 5I7 population. Although upconversion was still present in this experiment, it was possible to achieve efficient energy storage, demonstrating that the problem is manageable even at high excitation densities in YLF.

  9. New night vision goggle gain definition

    NASA Astrophysics Data System (ADS)

    Podobedov, Vyacheslav B.; Eppeldauer, George P.; Larason, Thomas C.

    2015-05-01

    A new definition is proposed for the calibration of Night Vision Goggle (NVG) gains. This definition is based on the measurement of radiometric input and output quantities of the NVG. While the old definition used the "equivalent fL" which is a non SI traceable luminance unit, the new definition utilizes the radiance quantities that are traceable to the SI units through NIST standards. The new NVG gain matches the previous one as a result of the application of a correction coefficient originating from the conversion of the radiance to luminance units. The new definition was tested at the NIST Night Vision Calibration Facility and the measurement results were compared to the data obtained with a Hoffman Test Set Model ANV-126. Comparing the radiometric quantities of the Hoffman Test Set and those measured by the NIST transfer standard radiometer, indicates that the observed differences up to 15% were due to the calibration and experimental errors of the ANV-126 Test Set. In view of different spectral characteristics of luminophores that can be utilized in the NVG design, the simulation of the NVG output for gain measurement was performed. The NVG output was simulated with a sphere-based source using different LEDs and the measured gain was compared to that obtained with the ANV-126 internal luminance meter. The NVG gain uncertainty analysis was performed for the Type A, B, and C goggles.

  10. Gain loss asymmetry for emerging stock markets

    NASA Astrophysics Data System (ADS)

    Karpio, Krzysztof; Załuska–Kotur, Magdalena A.; Orłowski, Arkadiusz

    2007-03-01

    Stock indexes for some European emerging markets are analyzed using an investment-horizon approach. Austrian ATX index and Dow Jones have been studied and compared with several emerging European markets. The optimal investment horizons are plotted as a function of an absolute return value. Gain-loss asymmetry, originally found for American DJIA index, is observed for all analyzed data. It is shown, that this asymmetry has different character for emerging and for established markets. For established markets, gain curve lies typically above loss curve, whereas in the case of emerging markets the situation is just the opposite. We propose a measure quantifying the gain-loss asymmetry that clearly exhibits a difference between emerging and established markets.

  11. [Atypical antipsychotic-induced weight gain].

    PubMed

    Godlewska, Beata R; Olajossy-Hilkesberger, Luiza; Marmurowska-Michałowska, Halina; Olajossy, Marcin; Landowski, Jerzy

    2006-01-01

    Introduction of a new group of antipsychotic drugs, called atypical because of the proprieties differing them from classical neuroleptics, gave hope for the beginning of a new era in treatment of psychoses, including schizophrenia. Different mechanisms of action not only resulted in a broader spectrum of action and high efficacy but also in a relative lack of extrapiramidal symptoms. However, atypical neuroleptics are not totally free from adverse effects. Symptoms such as sedation, metabolic changes and weight gain, often very quick and severe - present also in the case of classical drugs, but put to the background by extrapiramidal symptoms--have become prominent. Weight gain is important both from the clinical and subjective point of view--as associated with serious somatic consequences and as a source of enormous mental distress. These problems are addressed in this review, with the focus on weight gain associated with the use of specific atypical neuroleptics.

  12. Microstrip antenna gain enhancement with metamaterial radome

    NASA Astrophysics Data System (ADS)

    Attachi, S.; Saleh, C.; Bouzouad, M.

    2017-01-01

    In this work, a high gain patch antenna using multilayer FSS radome is proposed for millimeter-wave applications. The antenna operating frequency is 43.5 GHz. The antenna/radome system consists of one, two, three, or four layers of metasurfaces placed in the near-field region of a microstrip patch antenna. The antenna/radome system gain is improved by 9 dBi compared to the patch antenna alone, and the radiation pattern half-power beamwidth is reduces to 20° in both E- and H-planes.

  13. Gain vs phase in BOTDA setups

    NASA Astrophysics Data System (ADS)

    Lopez-Gil, Alexia; Angulo-Vinuesa, Xabier; Soto, Marcelo A.; Dominguez-Lopez, Alejandro; Martin-Lopez, Sonia; Thévenaz, Luc; Gonzalez-Herraez, Miguel

    2016-05-01

    We evaluate the Brillouin frequency shift (BFS) determination error when using the Brillouin phase spectrum (BPS) instead of the Brillouin gain spectrum (BGS) in BOTDA setups. We compare the error obtained in the BFS determination in both cases, both with theoretical arguments and experimental data. In comparison to the gain, for an equal SNR and linewidth, the phase generally provides a better fit of the BFS for smaller frequency spans. This result opens a possible way to reduce the measurement time of certain BOTDA systems by using the phase feature.

  14. Net Photorefractive Gain In Gallium Arsenide

    NASA Technical Reports Server (NTRS)

    Liu, Tsuen-Hsi; Cheng, Li-Jen

    1990-01-01

    Prerequisite includes applied electric field. Electric field applied to GaAs crystal in which two infrared beams interfere. Depending on quality of sample and experimental conditions, net photorefractive gain obtained. Results offer possibility of new developments in real-time optical processing of signals by use of near-infrared lasers of low power.

  15. Managing your weight gain during pregnancy

    MedlinePlus

    ... basis for a healthy pregnancy. For most pregnant women, the right amount of calories is: 1,800 calories per ... are already overweight when they get pregnant. Other women gain ... on eating the right foods and staying active. If you do not ...

  16. X chromosome gain in male breast cancer.

    PubMed

    Di Oto, Enrico; Monti, Valentina; Cucchi, Maria C; Masetti, Riccardo; Varga, Zsuzsanna; Foschini, Maria P

    2015-12-01

    Male breast cancer (MBC) is an uncommon disease whose molecular profile is not well known. X chromosome gain has been described as a marker of aggressive behavior in female breast cancer. The aim of this study is to investigate the role of the X chromosome in male breast cancer. Twenty cases of male breast invasive ductal carcinoma were retrieved and compared with 10 cases of gynecomastia. Cases were tested by fluorescence in situ hybridization to assess a cytogenetic profile for the X chromosome. The X chromosome status was compared with histopathologic features and stage at presentation. All MBC cases harbored an X chromosome gain (100%) in a variable percentage of neoplastic cells, ranging from 31% to 85% (mean, 59%). On the contrary, all cases of gynecomastia showed wild X chromosome asset. The patients' age at surgery and tumor grading showed a statistically significant correlation (P = .0188-.04), with the percentages of neoplastic cells showing an X chromosome gain. These data suggest that this X chromosome gain plays a role in the neoplastic transformation of male breast epithelial cells.

  17. 75 FR 63763 - Program Integrity: Gainful Employment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-18

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF EDUCATION 34 CFR Part 668 RIN 1840-AD04 Program Integrity: Gainful Employment AGENCY: Office of Postsecondary Education, Department of Education. ACTION: Notice of public meeting sessions. SUMMARY: The Secretary...

  18. Weight Gain Through Self-Control Procedures

    ERIC Educational Resources Information Center

    Gulanick, Nancy; And Others

    1975-01-01

    Underweight subjects were assigned to either a self-reinforcement condition, a self-punishment condition, or to a discussion/reflection control condition. The subjects received one treatment session per week over a five-week period. After treatment, the self-reinforcement groups gained significantly more pounds (kilograms) than either of the other…

  19. Gain of a single gas electron multiplier

    NASA Astrophysics Data System (ADS)

    Nemallapudi, Mythra Varun

    Gas Electron Multiplier (GEM) is a gaseous detector used in particle detection and is known for its high rate capability. Ever since its invention in 1997, GEM was applied in many areas and recently has been proposed to be installed in the CMS high η regions for upgrade at LHC, CERN. A complete understanding of the working and gain behaviour does not exist. GEM gain is influenced by charging up and this has been variedly interpreted in literature lacking consensus. I have attempted in this work through simulations and measurements to achieve a better understanding of single GEM gain and how it is affected by various factors. Specific experimental methods which evolved with subsequent measurements were employed to systematically study the charging up effect. Information from simulations was applied to characterize measurements thereby enabling the development of a model for charging up. Conductivity mechanism of the dielectric used in GEM was analyzed and the resistivity measured. Gain free of charging up effects was measured and this is appropriate for comparison with simulations.

  20. Body weight gain and deep brain stimulation.

    PubMed

    Rieu, Isabelle; Derost, Philippe; Ulla, Miguel; Marques, Ana; Debilly, Bérangère; De Chazeron, Ingrid; Chéreau, Isabelle; Lemaire, Jean Jacques; Boirie, Yves; Llorca, Pierre Michel; Durif, Franck

    2011-11-15

    Deep brain stimulation (DBS) is a neurosurgical technique that has now been available for some 25 years. It is used in the treatment of various motor disorders, e.g. Parkinson's disease (PD), essential tremor and dystonia, and neuropsychiatric illnesses, e.g. obsessive-compulsive disorder and Tourette syndrome. The surgical targets of DBS include the thalamic ventralis intermedius nucleus (Vim), the globus pallidus internus (GPi) and more recently the subthalamic nucleus (STN), currently considered as the reference target in the treatment of PD. In the last ten years, most studies in PD patients have described a rapid and marked weight gain in the months following DBS of the STN. This weight gain sometimes induces obesity and can have metabolic repercussions. The physiopathological mechanisms responsible for the weight gain are multifactorial (changes in energy metabolism and eating behaviour, reduction of motor complications, etc.). This review reports current knowledge concerning weight changes in patients treated by DBS with different surgical targets. It also describes the mechanisms responsible for weight gain and the health outcome for the patients.

  1. Sudden Gains during Therapy of Social Phobia

    ERIC Educational Resources Information Center

    Hofmann, Stefan G.; Schultz, Stefan M.; Meuret, Alicia E.; Moscovitch, David A.; Suvak, Michael

    2006-01-01

    The present study investigated the phenomenon of sudden gains in 107 participants with social phobia (social anxiety disorder) who received either cognitive-behavioral group therapy or exposure group therapy without explicit cognitive interventions, which primarily used public speaking situations as exposure tasks. Twenty-two out of 967…

  2. Optical gain by a simple photoisomerization process

    NASA Astrophysics Data System (ADS)

    Gallego-Gómez, Francisco; Del Monte, Francisco; Meerholz, Klaus

    2008-06-01

    Organic holographic materials are pursued as versatile and cheap data-storage materials. It is generally assumed that under steady-state conditions, only photorefractive holographic media exhibit a non-local response to a light-intensity pattern, which results in an asymmetric two-beam coupling or `gain', where intensity is transferred from one beam to the other as a measure of writing efficiency. Here, we demonstrate non-local holographic recording in a non-photorefractive material. We demonstrate that reversible photoisomerization gratings recorded in a non-photorefractive azo-based material exhibit large optical gain coefficients beyond 1,000cm-1, even for polarization gratings. The grating characteristics differ markedly from classical photorefractive features, but can be modelled by considering the influence of the Poynting vector on the photoisomerization. The external control of the Poynting vector enables manipulation of the gain coefficient, including its sign (the direction of energy exchange), a novel phenomenon we refer to as `gain steering'. A very high sensitivity of about 100cm2J-1 was achieved. This high sensitivity, combined with a high spatial resolution, suggests a great technical advantage for applications in image processing and phase conjugation.

  3. Gainful Employment: The Real Issue. Policy Memo

    ERIC Educational Resources Information Center

    Mandel, Michael

    2010-01-01

    Sometimes a proposed piece of legislation or new rule can catalyze debate about a key issue. That seems to be the case for the "gainful employment" rule currently being proposed by the Department of Education (DOE). The rule addresses a very real problem: The large amounts of debt being taken on by some students, mainly those attending for-profit…

  4. Autonomous Exploration Using an Information Gain Metric

    DTIC Science & Technology

    2016-03-01

    factors of the utility function, biasing the behavior toward either exploration or relocation. The simulated experiments demonstrate improved...also presented. 15. SUBJECT TERMS information gain, exploration, intelligent behaviors , simultaneous localization and mapping, SLAM, entropy 16...addition, the data collected over a variety of graph entropy scale values demonstrate the behavior of the algorithm when loop closures are

  5. Method and system for edge cladding of laser gain media

    DOEpatents

    Bayramian, Andrew James; Caird, John Allyn; Schaffers, Kathleen Irene

    2014-03-25

    A gain medium operable to amplify light at a gain wavelength and having reduced transverse ASE includes an input surface and an output surface opposing the input surface. The gain medium also includes a central region including gain material and extending between the input surface and the output surface along a longitudinal optical axis of the gain medium. The gain medium further includes an edge cladding region surrounding the central region and extending between the input surface and the output surface along the longitudinal optical axis of the gain medium. The edge cladding region includes the gain material and a dopant operable to absorb light at the gain wavelength.

  6. Association of gestational weight gain expectations with advice on actual weight gain

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To examine pregnant women's gestational weight gain expectations/advice from various sources (i.e., self, family/friends, physician) and the impact of these sources of expectations/advice on actual measured gestational weight gain. Pregnant women (n=230, 87.4% Caucasian, second pregnancy) in a cohor...

  7. 34 CFR 462.43 - How is educational gain measured?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 34 Education 3 2011-07-01 2011-07-01 false How is educational gain measured? 462.43 Section 462.43... ADULT EDUCATION, DEPARTMENT OF EDUCATION MEASURING EDUCATIONAL GAIN IN THE NATIONAL REPORTING SYSTEM FOR... Educational Gain? § 462.43 How is educational gain measured? (a)(1) Educational gain is measured by...

  8. The effect of dietary fish oil on weight gain and insulin sensitivity is dependent on APOE genotype in humanized targeted replacement mice

    PubMed Central

    Slim, Kenna E.; Vauzour, David; Tejera, Noemi; Voshol, Peter J.; Cassidy, Aedin; Minihane, Anne Marie

    2017-01-01

    We investigated the independent and interactive impact of the common APOE genotype and marine n-3 polyunsaturated fatty acids (PUFAs) on the development of obesity and associated cardiometabolic dysfunction in a murine model. Human APOE3 and APOE4 targeted replacement mice were fed either a control high-fat diet (HFD) or an HFD supplemented with 3% n-3 PUFAs from fish oil (HFD + FO) for 8 wk. We established the impact of intervention on food intake, body weight, and visceral adipose tissue (VAT) mass; plasma, lipids (cholesterol and triglycerides), liver enzymes, and adipokines; glucose and insulin during an intraperitoneal glucose tolerance test; and Glut4 and ApoE expression in VAT. HFD feeding induced more weight gain and higher plasma lipids in APOE3 compared to APOE4 mice (P < 0.05), along with a 2-fold higher insulin and impaired glucose tolerance. Supplementing APOE3, but not APOE4, animals with dietary n-3 PUFAs decreased body-weight gain, plasma lipids, and insulin (P < 0.05) and improved glucose tolerance, which was associated with increased VAT Glut4 mRNA levels (P < 0.05). Our findings demonstrate that an APOE3 genotype predisposes mice to develop obesity and its metabolic complications, which was attenuated by n-3 PUFA supplementation.—Slim, K. E., Vauzour, D., Tejera, N., Voshol, P. J., Cassidy, A., Minihane, A. M. The effect of dietary fish oil on weight gain and insulin sensitivity is dependent on APOE genotype in humanized targeted replacement mice. PMID:27895108

  9. Weight gain and reduced energy expenditure in low-income Brazilian women living in slums: a 4-year follow-up study.

    PubMed

    Florêncio, Telma M M T; Bueno, Nassib B; Clemente, Ana P G; Albuquerque, Fabiana C A; Britto, Revilane P A; Ferriolli, Eduardo; Sawaya, Ana L

    2015-08-14

    The present study aimed to investigate the possible changes in anthropometric and biochemical parameters in low-income women living in the outskirts of Maceió (northeast Brazil), and to explore the possible role of dietary intake and physical activity in these changes. A prospective longitudinal study was conducted in a cohort of mothers of malnourished children who attended the Center for Nutritional Recovery and Education, an outreach programme of the Federal University of Alagoas. Socio-economic, anthropometric, biochemical and dietary intake data were assessed at baseline and after a follow-up period of 4 years. Energy expenditure (using doubly labelled water) and physical activity (using triaxial accelerometers) were assessed only in a subgroup of women after 4 years. A total of eighty-five women were assessed. Participants showed an altered biochemical profile, increased systolic blood pressure, decreased thyroid hormone levels, and body-weight gain. However, dietary intakes of the participants did not include large quantities of highly processed and high-glycaemic index foods. The energy intake of the participants did not differ from their total energy expenditure (7990.3 (7173.7-8806.8) v. 8798.1 (8169.0-9432.4) kJ, respectively; P= 0.084). Multivariate analyses showed a significant effect of time spent watching television (β = 0.639 (0.003 to 1.275); P= 0.048) and dietary diversity score (β = -1.039 ( -2.010 to -0.067); P = 0.036) on weight gain. The present study indicates that poor women, who are mothers of malnourished children and have a reasonably balanced dietary intake, exhibit weight gain and are at risk of developing chronic diseases.

  10. The use of LeptiCore® in reducing fat gain and managing weight loss in patients with metabolic syndrome

    PubMed Central

    2010-01-01

    Background LeptiCore® is a proprietary combination of various ingredients which have been shown to have properties which could be beneficial to weight loss in obese and overweight human subjects. This study evaluates the effect of Lepticore® on bodyweight as well as parameters associated with obesity and metabolic syndrome. Methods The study was an 8 week randomized, double-blind, placebo-controlled design involving 92 obese (mean BMI > 30 kg/m2) participants (37 males; 55 females; ages 19-52; mean age = 30.7). The participants were randomly divided into three groups: placebo (n = 30), LeptiCore® formula A (low dose) (n = 31) and LeptiCore® formula B (high dose) (n = 31). Capsules containing the placebo or active formulations were administered twice daily before meals with 300 ml of water. None of the participants followed any specific diet nor took any weight-reducing medications for the duration of the study. A total of 12 anthropomorphic and serological measurements were taken at the beginning of the study and after 2, 4, 6, and 8 weeks of treatment. Results Compared to the placebo group, the two active groups showed statistically significant differences on all 12 variables by week 8. These included four anthropomorphic variables (body weight, body fat, waist and hip size) and eight measures of serological levels (plasma total cholesterol, LDL, HDL, triglycerides, blood glucose, serotonin, leptin, C-reactive protein). The two active groups also showed significant intra-group differences on all 12 variables between study onset and week 8. Conclusion The LeptiCore® formulation at both the low and high dosages appears to be helpful in the management of fat gain and its related complications. The higher dosage resulted in significantly greater reductions in body weight and triglyceride, blood glucose, and C-reactive protein levels, as well as increased serotonin levels. PMID:20170522

  11. Gain scaling for multirate filter banks

    SciTech Connect

    Brislawn, Christopher M

    2009-01-01

    Eliminating two trivial degrees of freedom corresponding to the lowpass DC response and the highpass Nyquist response in a two-channel multirate filter bank seems simple enough. Nonetheless, the ISO/IEC JPEG 2000 image coding standard manages to make this mundane task look totally mysterious. We reveal the true meaning behind JPEG 2000's arcane specifications for filter bank normalization and point out how the seemingly trivial matter of gain scaling leads to highly nontrivial issues concerning uniqueness of lifting factorizations.

  12. High gain feedback and telerobotic tracking

    NASA Technical Reports Server (NTRS)

    Koditschek, D. E.

    1987-01-01

    Asymptotically stable linear time invariant systems are capable of tracking arbitrary reference signals with a bounded error proportional to the magnitude of the reference signal (and its derivatives). It is shown that a similar property holds for a general class of nonlinear dynamical systems which includes all robots. As in the linear case, the error bound may be made arbitrarily small by increasing the magnitude of the feedback gains which stabilize the system.

  13. Mispredicting the Hedonic Benefits of Segregated Gains

    ERIC Educational Resources Information Center

    Morewedge, Carey K.; Gilbert, Daniel T.; Keysar, Boaz; Berkovits, Michael J.; Wilson, Timothy D.

    2007-01-01

    The hedonic benefit of a gain (e.g., receiving $100) may be increased by segregating it into smaller units that are distributed over time (e.g., receiving $50 on each of 2 days). However, if these units are too small (e.g., receiving 1 cent on each of 10,000 days), they may fall beneath the person's hedonic limen and have no hedonic benefit at…

  14. Optical antenna gain. II - Receiving antennas

    NASA Technical Reports Server (NTRS)

    Degnan, J. J.; Klein, B. J.

    1974-01-01

    Expressions are developed for the gain of a centrally obscured, circular optical antenna used as the collecting and focusing optics in a laser receiver, involving losses due to (1) incoming light blockage by central obscuration, (2) energy spillover at the detector, and (3) the effect of local oscillator distribution in the case of heterodyne or homodyne detection. Numerical results are presented for direct detection and for three types of local oscillator distribution (uniform, Gaussian, and matched).

  15. The Comstar D/3 gain degradation experiment

    NASA Technical Reports Server (NTRS)

    Lee, T. C.; Hodge, D. B.

    1981-01-01

    The results of gain degradation measurements using the Comstar D/3 19.04 GHz beacon are reported. This experiment utilized 0.6 and 5 m aperture antennas aligned along the same propagation path to examine propagation effects which are related to the antenna aperture size. Sample data for clear air, scintillation in clear air, and precipitation fading are presented. Distributions of the received signal levels and variances for both antennas are also presented.

  16. Loss/gain-induced ultrathin antireflection coatings.

    PubMed

    Luo, Jie; Li, Sucheng; Hou, Bo; Lai, Yun

    2016-06-28

    Tradional antireflection coatings composed of dielectric layers usually require the thickness to be larger than quarter wavelength. Here, we demonstrate that materials with permittivity or permeability dominated by imaginary parts, i.e. lossy or gain media, can realize non-resonant antireflection coatings in deep sub-wavelength scale. Interestingly, while the reflected waves are eliminated as in traditional dielectric antireflection coatings, the transmitted waves can be enhanced or reduced, depending on whether gain or lossy media are applied, respectively. We provide a unified theory for the design of such ultrathin antireflection coatings, showing that under different polarizations and incident angles, different types of ultrathin coatings should be applied. Especially, under transverse magnetic polarization, the requirement shows a switch between gain and lossy media at Brewster angle. As a proof of principle, by using conductive films as a special type of lossy antireflection coatings, we experimentally demonstrate the suppression of Fabry-Pérot resonances in a broad frequency range for microwaves. This valuable functionality can be applied to remove undesired resonant effects, such as the frequency-dependent side lobes induced by resonances in dielectric coverings of antennas. Our work provides a guide for the design of ultrathin antireflection coatings as well as their applications in broadband reflectionless devices.

  17. Loss/gain-induced ultrathin antireflection coatings

    PubMed Central

    Luo, Jie; Li, Sucheng; Hou, Bo; Lai, Yun

    2016-01-01

    Tradional antireflection coatings composed of dielectric layers usually require the thickness to be larger than quarter wavelength. Here, we demonstrate that materials with permittivity or permeability dominated by imaginary parts, i.e. lossy or gain media, can realize non-resonant antireflection coatings in deep sub-wavelength scale. Interestingly, while the reflected waves are eliminated as in traditional dielectric antireflection coatings, the transmitted waves can be enhanced or reduced, depending on whether gain or lossy media are applied, respectively. We provide a unified theory for the design of such ultrathin antireflection coatings, showing that under different polarizations and incident angles, different types of ultrathin coatings should be applied. Especially, under transverse magnetic polarization, the requirement shows a switch between gain and lossy media at Brewster angle. As a proof of principle, by using conductive films as a special type of lossy antireflection coatings, we experimentally demonstrate the suppression of Fabry-Pérot resonances in a broad frequency range for microwaves. This valuable functionality can be applied to remove undesired resonant effects, such as the frequency-dependent side lobes induced by resonances in dielectric coverings of antennas. Our work provides a guide for the design of ultrathin antireflection coatings as well as their applications in broadband reflectionless devices. PMID:27349750

  18. Optical antenna gain. 2: receiving antennas.

    PubMed

    Degnan, J J; Klein, B J

    1974-10-01

    Expressions are derived for the gain of a centrally obscured, circular optical antenna when used as the collecting and focusing optics in a laser receiver which include losses due to (1) blockage of the incoming light by the central obscuration, (2) the spillover of energy at the detector, and (3) the effect of local oscillator distribution in the case of heterodyne or homodyne detection. Numerical results are presented for direct detection and for three types of local oscillator distributions (uniform, Gaussian, and matched) in the case of heterodyne or homodyne detection. The results are presented in several graphs that allow the rapid evaluation of receiver gain for an arbitrary set of telescope and detector parameters. It is found that, for uniform illumination by the LO, the optimum SNR is obtained when the detector radius is approximately 0.74 times the Airy disk radius. The use of an optimized Gaussian (spot size = 0.46 times the Airy disk radius) improves the receiver gain by less than 1 dB. Theuse results are insensitive to the size of the central obscuration.

  19. Raman gains of ADP and KDP crystals

    NASA Astrophysics Data System (ADS)

    Zhou, Hai-Liang; Zhang, Qing-Hua; Wang, Bo; Xu, Xin-Guang; Wang, Zheng-Ping; Sun, Xun; Zhang, Fang; Zhang, Li-Song; Liu, Bao-An; Chai, Xiang-Xu

    2015-04-01

    In this paper, the Raman gain coefficients of ammonium dihydrogen phosphate (ADP) and potassium dihydrogen phosphate (KDP) crystals are measured. By using a pump source of a 30-ps, 532-nm laser, the gain coefficients of ADP and KDP are 1.22 cm/GW, and 0.91 cm/GW, respectively. While for a 20-ps, 355-nm pump laser, the gain coefficients of these two crystals are similar, which are 1.95 cm/GW for ADP and 1.86 for KDP. The present results indicate that for ultra-violet frequency conversion, the problem of stimulated Raman scattering for ADP crystal will not be more serious than that for KDP crystal. Considering other advantages such the larger nonlinear optical coefficient, higher laser damage threshold, and lower noncritical phase-matching temperature, it can be anticipated that ADP will be a powerful competitor to KDP in large aperture, high energy third-harmonic generation or fourth-harmonic generation applications. Project supported by the National Natural Science Foundation of China (Grant Nos. 51323002 and 51402173), the Independent Innovation Foundation of Shandong University, China (Grant Nos. IIFSDU and 2012JC016), the Program for New Century Excellent Talents in University, China (Grant No. NCET-10-0552), the Fund from the Key Laboratory of Neutron Physics, China Academy of Engineering Physics (Grant No. 2014BB07), and the Natural Science Foundation for Distinguished Young Scholar of Shandong Province, China (Grant No. JQ201218).

  20. Optical antenna gain. III - The effect of secondary element support struts on transmitter gain

    NASA Technical Reports Server (NTRS)

    Klein, B. J.; Degnan, J. J.

    1976-01-01

    The effect of a secondary-element spider support structure on optical antenna transmitter gain is analyzed. An expression describing the influence of the struts on the axial gain, in both the near and far fields, is derived as a function of the number of struts and their width. It is found that, for typical systems, the struts degrade the on-axis gain by less than 0.4 dB, and the first side-lobe level is not increased significantly. Contour plots have also been included to show the symmetry of the far-field distributions for three- and four-support members.

  1. Optical antenna gain. 3: The effect of secondary element support struts on transmitter gain.

    PubMed

    Klein, B J; Degnan, J J

    1976-04-01

    The effect of a secondary element spider support structure on optical antenna transmitter gain is analyzed. An expression describing the influence of the struts on the axial gain, in both the near and far fields, is derived as a function of the number of struts and their width. It is found that, for typical systems, the struts degrade the on-axis gain by less than 0.4 dB, and the first side-lobe level is not increased significantly. Contour plots have also been included to show the symmetry of the far-field distributions for three and four support members.

  2. Interventions to reduce weight gain in schizophrenia

    PubMed Central

    Faulkner, Guy; Cohn, Tony; Remington, Gary

    2014-01-01

    Background Weight gain is common for people with schizophrenia and this has serious implications for health and well being. Objectives To determine the effects of both pharmacological (excluding medication switching) and non pharmacological strategies for reducing or preventing weight gain in people with schizophrenia. Search methods We searched key databases and the Cochrane Schizophrenia Group’s trials register (April 2006), reference sections within relevant papers, hand searched key journals, and contacted the first author of each relevant study and other experts to collect further information. Selection criteria We included all clinical randomised controlled trials comparing any pharmacological or non pharmacological intervention for weight gain (diet and exercise counselling) with standard care or other treatments for people with schizophrenia or schizophrenia-like illnesses. Data collection and analysis We reliably selected, quality assessed and extracted data from studies. As weight is a continuous outcome measurement, weighted mean differences (WMD) of the change from baseline were calculated. The primary outcome measure was weight loss. Main results Twenty-three randomised controlled trials met the inclusion criteria for this review. Five trials assessed a cognitive/behavioural intervention and eighteen assessed a pharmacological adjunct. In terms of prevention, two cognitive/behavioural trials showed significant treatment effect (mean weight change) at end of treatment (n=104, 2 RCTs, WMD −3.38 kg CI −4.2 to −2.0). Pharmacological adjunct treatments were significant with a modest prevention of weight gain (n=274, 6 RCTs, WMD − 1.16 kg CI −1.9 to −0.4). In terms of treatments for weight loss, we found significantly greater weight reduction in the cognitive behavioural intervention group (n=129, 3 RCTs, WMD −1.69 kg CI −2.8 to −0.6) compared with standard care. Authors’ conclusions Modest weight loss can be achieved with selective

  3. Effects of Gain Changes on RPM Performance

    SciTech Connect

    Lousteau, Angela L; York, Robbie Lynn; Livesay, Jake

    2012-03-01

    The mission of the U.S. Department of Energy/National Nuclear Security Administration's (DOE/NNSA's) Office of the Second Line of Defense (SLD) is to strengthen the capability of foreign governments to deter, detect, and interdict the illicit trafficking of special nuclear and other radioactive materials across international borders and through the global maritime shipping system. The goal of this mission is to reduce the probability of these materials being fashioned into a weapon of mass destruction or radiological dispersal device that could be used against the United States or its international partners. This goal is achieved primarily through the installation and operation of radiation detection equipment at border crossings, airports, seaports, and other strategic locations around the world. In order to effectively detect the movement of radioactive material, the response of these radiation detectors to various materials in various configurations must be well characterized. Oak Ridge National Laboratory (ORNL) investigated two aspects of Radiation Portal Monitor (RPM) settings, based on a preliminary investigation done by the Los Alamos National Laboratory (LANL): source-to-detector distance effect on amplifier gain and optimized discriminator settings. This report discusses this investigation. A number of conclusions can be drawn from the ORNL testing. First, for increased distance between the source and the detector, thus illuminating the entire detector rather than just the center of the detector (as is done during detector alignments), an increase in gain may provide a 5-15% increase in sensitivity (Fig. 4). However, increasing the gain without adjusting the discriminator settings is not recommended as this makes the monitor more sensitive to electronic noise and temperature-induced fluctuations. Furthermore, if the discriminators are adjusted in relation to the increase in gain, thus appropriately discriminating against electronic noise, the sensitivity

  4. Sympathetic baroreflex gain in normotensive pregnant women

    PubMed Central

    Usselman, Charlotte W.; Skow, Rachel J.; Matenchuk, Brittany A.; Chari, Radha S.; Julian, Colleen G.; Stickland, Michael K.; Davenport, Margie H.

    2015-01-01

    Muscle sympathetic nerve activity is increased during normotensive pregnancy while mean arterial pressure is maintained or reduced, suggesting baroreflex resetting. We hypothesized spontaneous sympathetic baroreflex gain would be reduced in normotensive pregnant women relative to nonpregnant matched controls. Integrated muscle sympathetic burst incidence and total sympathetic activity (microneurography), blood pressure (Finometer), and R-R interval (ECG) were assessed at rest in 11 pregnant women (33 ± 1 wk gestation, 31 ± 1 yr, prepregnancy BMI: 23.5 ± 0.9 kg/m2) and 11 nonpregnant controls (29 ± 1 yr; BMI: 25.2 ± 1.7 kg/m2). Pregnant women had elevated baseline sympathetic burst incidence (43 ± 2 vs. 33 ± 2 bursts/100 heart beats, P = 0.01) and total sympathetic activity (1,811 ± 148 vs. 1,140 ± 55 au, P < 0.01) relative to controls. Both mean (88 ± 3 vs. 91 ± 2 mmHg, P = 0.4) and diastolic (DBP) (72 ± 3 vs. 73 ± 2 mmHg, P = 0.7) pressures were similar between pregnant and nonpregnant women, respectively, indicating an upward resetting of the baroreflex set point with pregnancy. Baroreflex gain, calculated as the linear relationship between sympathetic burst incidence and DBP, was reduced in pregnant women relative to controls (−3.7 ± 0.5 vs. −5.4 ± 0.5 bursts·100 heart beats−1·mmHg−1, P = 0.03), as was baroreflex gain calculated with total sympathetic activity (−294 ± 24 vs. −210 ± 24 au·100 heart beats−1·mmHg−1; P = 0.03). Cardiovagal baroreflex gain (sequence method) was not different between nonpregnant controls and pregnant women (49 ± 8 vs. 36 ± 8 ms/mmHg; P = 0.2). However, sympathetic (burst incidence) and cardiovagal gains were negatively correlated in pregnant women (R = −0.7; P = 0.02). Together, these data indicate that the influence of the sympathetic nervous system over arterial blood pressure is reduced in normotensive pregnancy, in terms of both long-term and beat-to-beat regulation of arterial pressure

  5. Theory of noise in high-gain surface plasmon-polariton amplifiers incorporating dipolar gain media.

    PubMed

    De Leon, Israel; Berini, Pierre

    2011-10-10

    A theoretical analysis of noise in high-gain surface plasmon-polariton amplifiers incorporating dipolar gain media is presented. An expression for the noise figure is obtained in terms of the spontaneous emission rate into the amplified surface plasmon-polariton taking into account the different energy decay channels experienced by dipoles in close proximity to the metallic surface. Two amplifier structures are examined: a single-interface between a metal and a gain medium and a thin metal film bounded by identical gain media on both sides. A realistic configuration is considered where the surface plasmon-polariton undergoing amplification has a Gaussian field profile in the plane of the metal and paraxial propagation along the amplifier's length. The noise figure of these plasmonic amplifiers is studied considering three prototypical gain media with different permittivities. It is shown that the noise figure exhibits a strong dependance on the real part of the permittivities of the metal and gain medium, and that its minimum value is 4/π(∼3.53 dB). The origin of this minimum value is discussed. It is also shown that amplifier configurations supporting strongly confined surface plasmon-polaritons suffer from a large noise figure, which follows from an enhanced spontaneous emission rate due to the Purcell effect.

  6. Gain results for low voltage FEL

    SciTech Connect

    Shaw, A.; Stuart, R.A.; Al-Shamma`a, A.

    1995-12-31

    We have designed and constructed a low voltage (130 kV) FEL system capable of operating in the microwave frequency range for which the electron beam current is cw (rather than pulsed) in time at a level of {approximately} 12 mA. The gain of this system has been measured as a function of the electron beam accelerating voltage and current level, and the input microwave frequency (8-10 GHz). The results are compared with the predictions of a simple theoretical model.

  7. Semiconductor radiation detector with internal gain

    DOEpatents

    Iwanczyk, Jan; Patt, Bradley E.; Vilkelis, Gintas

    2003-04-01

    An avalanche drift photodetector (ADP) incorporates extremely low capacitance of a silicon drift photodetector (SDP) and internal gain that mitigates the surface leakage current noise of an avalanche photodetector (APD). The ADP can be coupled with scintillators such as CsI(Tl), NaI(Tl), LSO or others to form large volume scintillation type gamma ray detectors for gamma ray spectroscopy, photon counting, gamma ray counting, etc. Arrays of the ADPs can be used to replace the photomultiplier tubes (PMTs) used in conjunction with scintillation crystals in conventional gamma cameras for nuclear medical imaging.

  8. Neuronal Plasticity: Increasing the Gain in Pain

    NASA Astrophysics Data System (ADS)

    Woolf, Clifford J.; Salter, Michael W.

    2000-06-01

    We describe those sensations that are unpleasant, intense, or distressing as painful. Pain is not homogeneous, however, and comprises three categories: physiological, inflammatory, and neuropathic pain. Multiple mechanisms contribute, each of which is subject to or an expression of neural plasticity-the capacity of neurons to change their function, chemical profile, or structure. Here, we develop a conceptual framework for the contribution of plasticity in primary sensory and dorsal horn neurons to the pathogenesis of pain, identifying distinct forms of plasticity, which we term activation, modulation, and modification, that by increasing gain, elicit pain hypersensitivity.

  9. Gravity aided inertial navigation system (GAINS)

    NASA Astrophysics Data System (ADS)

    Jircitano, Albert; Dosch, Daniel E.

    The paper describes a new autonomous covert INS uniquely suited to underwater applications. Unlike the conventional INS, schuler and siderial errors are bounded without external navigation aids or active instrumentation of ground speed. As a result, the system exhibits excellent long-term navigation performance while maintaining the inherent covertness of the INS system. A conventional INS is integrated with a gravity gradiometer capable of measuring gravity field components independently of platform accelerations. This new integration scheme takes advantage of navigation system velocity error observability. Parametric performance results are presented for GAINS, varying gyro, gravimeter, gradiometer, depth sensor quality, and gravity field activity.

  10. Development of the Exercise Motives and Gains Inventory

    ERIC Educational Resources Information Center

    Strömmer, Sofia T.; Ingledew, David K.; Markland, David

    2015-01-01

    There are existing measures of exercise motives (what people want from exercise), but corresponding measures of gains (what people get) are needed, because motives and gains could influence each other and together influence other variables. An exercise motives and gains inventory (EMGI) was developed by creating gains scales to complement existing…

  11. IQ Gains in Argentina between 1964 and 1998

    ERIC Educational Resources Information Center

    Flynn, James R.; Rossi-Case, Lilia

    2012-01-01

    The literature on IQ gains in Latin America is sparse. We estimate gains on Raven's Progressive Matrices in the city of La Plata (Argentina) between 1964 and 1998. The gains are robust at the top of the curve as well as at the bottom. Therefore, they are contrary to the hypothesis that nutrition played a major role in recent Argentine IQ gains.…

  12. Gain control in the sonar of odontocetes.

    PubMed

    Ya Supin, Alexander; Nachtigall, Paul E

    2013-06-01

    The sonar of odontocetes processes echo-signals within a wide range of echo levels. The level of echoes varies widely by tens of decibels depending on the level of the emitted sonar pulse, the target strength, the distance to the target, and the sound absorption by the water media. The auditory system of odontocetes must be capable of effective perception, analysis, and discrimination of echo-signals within all this variability. The sonar of odontocetes has several mechanisms to compensate for the echo-level variation (gain control). To date, several mechanisms of the biosonar gain control have been revealed in odontocetes: (1) adjustment of emitted sonar pulse levels (the longer the distance to the target, the higher the level of the emitted pulse), (2) short-term variation of hearing sensitivity based on forward masking of the echo by the preceding self-heard emitted pulse and subsequent release from the masking, and (3) active long-term control of hearing sensitivity. Recent investigations with the use of the auditory evoked-potential technique have demonstrated that these mechanisms effectively minimize the variation of the response to the echo when either the emitted sonar pulse level, or the target distance, or both vary within a wide range. A short review of these data is presented herein.

  13. Brain Gain am Beispiel Österreich

    NASA Astrophysics Data System (ADS)

    Aschbacher, Christine; Gejguš, Mirko; Sablik, Jozef

    2016-06-01

    BrainGain is a common trend within the last ten years in Europe and all-over the world. Managers, key players and scientists are allowed to choose wherever they want to work in the world. As there is a lack of qualified individuals for companies and universities, BrainGain has become a necessity, and mostly - the higher educated individuals are moving away according to a better offer elsewhere in the world. Therefore, a lot of expats are moving around with their families. Many times, the lack of integration at the current place, country or city, is the critical success factor for staying or leaving. Furthermore, if the family does not feel happy in the current location, then the manager or scientist will move away or return home and the investment will be lost. Moreover, many students have received a good education in a state university, however afterwards they have not secured a satisfactory job in the country where they have studied, therefore they are moving away to utilise their know-how. Measures to retain the know-how include a common placement and a welcome-culture in the country, and also exchanges on an international level.

  14. Hybrid optical antenna with high directivity gain.

    PubMed

    Bonakdar, Alireza; Mohseni, Hooman

    2013-08-01

    Coupling of a far-field optical mode to electronic states of a quantum absorber or emitter is a crucial process in many applications, including infrared sensors, single molecule spectroscopy, and quantum metrology. In particular, achieving high quantum efficiency for a system with a deep subwavelength quantum absorber/emitter has remained desirable. In this Letter, a hybrid optical antenna based on coupling of a photonic nanojet to a metallo-dielectric antenna is proposed, which allows such efficient coupling. A quantum efficiency of about 50% is predicted for a semiconductor with volume of ~λ³/170. Despite the weak optical absorption coefficient of 2000 cm(-1) in the long infrared wavelength of ~8 μm, very strong far-field coupling has been achieved, as evidenced by an axial directivity gain of 16 dB, which is only 3 dB below of theoretical limit. Unlike the common phased array antenna, this structure does not require coherent sources to achieve a high directivity. The quantum efficiency and directivity gain are more than an order of magnitude higher than existing metallic, dielectric, or metallo-dielectric optical antenna.

  15. Compensated gain control circuit for buck regulator command charge circuit

    DOEpatents

    Barrett, David M.

    1996-01-01

    A buck regulator command charge circuit includes a compensated-gain control signal for compensating for changes in the component values in order to achieve optimal voltage regulation. The compensated-gain control circuit includes an automatic-gain control circuit for generating a variable-gain control signal. The automatic-gain control circuit is formed of a precision rectifier circuit, a filter network, an error amplifier, and an integrator circuit.

  16. Compensated gain control circuit for buck regulator command charge circuit

    DOEpatents

    Barrett, D.M.

    1996-11-05

    A buck regulator command charge circuit includes a compensated-gain control signal for compensating for changes in the component values in order to achieve optimal voltage regulation. The compensated-gain control circuit includes an automatic-gain control circuit for generating a variable-gain control signal. The automatic-gain control circuit is formed of a precision rectifier circuit, a filter network, an error amplifier, and an integrator circuit. 5 figs.

  17. Requiem for nutrition as the cause of IQ gains: Raven's gains in Britain 1938-2008.

    PubMed

    Flynn, James R

    2009-03-01

    The hypothesis that enhanced nutrition is mainly responsible for massive IQ gains over time borrows plausibility from the height gains of the 20th century. However, evidence shows that the two trends are largely independent. A detailed analysis of IQ trends on the Raven's Progressive Matrices tests in Britain dramatizes the poverty of the nutrition hypothesis. A multiple factor hypothesis that operates on three levels is offered as an alternative instrument of causal explanation. The Raven's data show that over the 65 years from circa 1942 to the present, taking ages 5-15 together, British school children have gained 14 IQ points for a rate of 0.216 points per year. However, since 1979, gains have declined with age and between the ages of 12-13 and 14-15, small gains turn into small losses. This is confirmed by Piagetian data and poses the possibility that the cognitive demands of teen-age subculture have been stagnant over perhaps the last 30 years.

  18. Two-dimensional gain cross-grating based on spatial modulation of active Raman gain

    NASA Astrophysics Data System (ADS)

    Wang, Li; Zhou, Feng-Xue; Guo, Hong-Ju; Niu, Yue-Ping; Gong, Shang-Qing

    2016-11-01

    Based on the spatial modulation of active Raman gain, a two-dimensional gain cross-grating is theoretically proposed. As the probe field propagates along the z direction and passes through the intersectant region of the two orthogonal standing-wave fields in the x-y plane, it can be effectively diffracted into the high-order directions, and the zero-order diffraction intensity is amplified at the same time. In comparison with the two-dimensional electromagnetically induced cross-grating based on electromagnetically induced transparency, the two-dimensional gain cross-grating has much higher diffraction intensities in the first-order and the high-order directions. Hence, it is more suitable to be utilized as all-optical switching and routing in optical networking and communication. Project supported by the National Natural Science Foundation of China (Grant Nos. 11274112 and 11347133).

  19. Gaining Public Support for RFI Mitigation

    NASA Astrophysics Data System (ADS)

    Finley, D. G.

    2004-05-01

    Astronomy's access to radio spectrum depends to a great extent on international and national regulatory agencies. Such regulation is inherently a political process, so support for radio astronomy by the general public is vital to success. Educating the public about a subject perceived as so highly technical can be challenging. Success in advancing public understanding of the issue and gaining public support is based on two foundations: publicizing the societal value of astronomy; and explaining the interference problem in non-technical terms that draw upon the well-understood terminology of environmental protection. Effective communication can convince non-scientists that astronomical research is a vital and beneficial activity, and that unpolluted access to the radio spectrum is essential to making the new discoveries that are astronomy's contribution to humanity. Convinced of this, the public will support imposing the expense of engineering measures designed to protect radio astronomy, just as they support spending money to protect air, water and soil from pollution.

  20. Management of Antipsychotic-Related Weight Gain

    PubMed Central

    Maayan, Lawrence; Correll, Christoph U.

    2012-01-01

    Despite variations across individuals and agents, antipsychotics are associated with clearly documented weight gain and adverse metabolic effects. Although increased appetite/caloric intake and various receptors, hormones and peptides have been implicated, biological mechanisms contributing to the increase in weight and glucose and lipid abnormalities with antipsychotics are largely unknown. This has hampered the creation of antipsychotics that are free of cardiometabolic effects, even in antipsychotic-naïve/early-phase patients, as well as the development of strategies that can prevent or drastically diminish the adverse cardiometabolic effects. In general, three strategies can reduce the cardiometabolic risk of antipsychotics: 1) switching to a less orexigenenic/metabolically adverse antipsychotic, 2) adjunctive behavioral treatments and 3) adjunctive pharmacologic interventions. However each of these strategies has only been modestly effective. Among different behavioral interventions (N=14, n=746), group and individual treatment, dietary counseling and cognitive-behavioral therapy seem to be similarly effective. Among 15 different pharmacologic strategies (N=35 , n=1,629), only metformin, fenfluramine, sibutramine, topiramate and reboxetine were more effective than placebo, with the most evidence being available for metformin, yet without any head-to-head trials comparing individual pharmacologic interventions. Even in the most successful trials, however, the risk reduction was modest. Weight was not decreased to a pre-treatment level, and despite superiority compared to placebo, weight gain still often occurred, particularly in antipsychotic-naïve patients and when interventions were “preventively” co-initiated with antipsychotics. Future research should focus on combining treatment modalities or agents and on exploring novel mechanism-based interventions. PMID:20586697

  1. Focusing on Short-Term Achievement Gains Fails to Produce Long-Term Gains

    ERIC Educational Resources Information Center

    Grissmer, David W.; Ober, David R.; Beekman, John A.

    2014-01-01

    The short-term emphasis engendered by No Child Left Behind (NCLB) has focused research predominantly on unraveling the complexities and uncertainties in assessing short-term results, rather than developing methods and assessing results over the longer term. In this paper we focus on estimating long-term gains and address questions important to…

  2. Analysis of Gain-Switching Characteristics Including Strong Gain Saturation Effects in Low-Dimensional Semiconductor Lasers

    NASA Astrophysics Data System (ADS)

    Chen, Shaoqiang; Yoshita, Masahiro; Ito, Takashi; Mochizuki, Toshimitsu; Akiyama, Hidefumi; Yokoyama, Hiroyuki; Kamide, Kenji; Ogawa, Tetsuo

    2012-09-01

    The effects of gain nonlinearities on gain-switched short-pulse-generation characteristics are analyzed via rate equations assuming a nonlinear-gain model including a gain saturation parameter gs to quantitatively describe the strong gain-saturation nonlinearity in low-dimensional semiconductor lasers at high carrier densities. It was found that the minimum pulse width and the delay time are mainly determined by gs rather than a differential gain coefficient g0 and a gain compression factor ɛ. By tracing the temporal evolution of carrier density, photon density, and material gain during gain switching, distinctly different effects of gs, ɛ, and cavity lifetime τp on pulse generation were clarified.

  3. Studies on pressure-gain combustion engines

    NASA Astrophysics Data System (ADS)

    Matsutomi, Yu

    Various aspects of the pressure-gain combustion engine are investigated analytically and experimentally in the current study. A lumped parameter model is developed to characterize the operation of a valveless pulse detonation engine. The model identified the function of flame quenching process through gas dynamic process. By adjusting fuel manifold pressure and geometries, the duration of the air buffer can be effectively varied. The parametric study with the lumped parameter model has shown that engine frequency of up to approximately 15 Hz is attainable. However, requirements for upstream air pressure increases significantly with higher engine frequency. The higher pressure requirement indicates pressure loss in the system and lower overall engine performance. The loss of performance due to the pressure loss is a critical issue for the integrated pressure-gain combustors. Two types of transitional methods are examined using entropy-based models. An accumulator based transition has obvious loss due to sudden area expansion, but it can be minimized by utilizing the gas dynamics in the combustion tube. An ejector type transition has potential to achieve performance beyond the limit specified by a single flow path Humphrey cycle. The performance of an ejector was discussed in terms of apparent entropy and mixed flow entropy. Through an ideal ejector, the apparent part of entropy increases due to the reduction in flow unsteadiness, but entropy of the mixed flow remains constant. The method is applied to a CFD simulation with a simple manifold for qualitative evaluation. The operation of the wave rotor constant volume combustion rig is experimentally examined. The rig has shown versatility of operation for wide range of conditions. Large pressure rise in the rotor channel and in a section of the exhaust duct are observed even with relatively large leakage gaps on the rotor. The simplified analysis indicated that inconsistent combustion is likely due to insufficient

  4. Effects of internal gain assumptions in building energy calculations

    SciTech Connect

    Christensen, C.; Perkins, R.

    1981-01-01

    The utilization of direct solar gains in buildings can be affected by operating profiles, such as schedules for internal gains, thermostat controls, and ventilation rates. Building energy analysis methods use various assumptions about these profiles. The effects of typical internal gain assumptions in energy calculations are described. Heating and cooling loads from simulations using the DOE 2.1 computer code are compared for various internal-gain inputs: typical hourly profiles, constant average profiles, and zero gain profiles. Prototype single-family-detached and multi-family-attached residential units are studied with various levels of insulation and infiltration. Small detached commercial buildings and attached zones in large commercial buildings are studied with various levels of internal gains. The results of this study indicate that calculations of annual heating and cooling loads are sensitive to internal gains, but in most cases are relatively insensitive to hourly variations in internal gains.

  5. Effects of internal gain assumptions in building energy calculations

    NASA Astrophysics Data System (ADS)

    Christensen, C.; Perkins, R.

    1981-01-01

    The utilization of direct solar gains in buildings can be affected by operating profiles, such as schedules for internal gains, thermostat controls, and ventilation rates. Building energy analysis methods use various assumptions about these profiles. The effects of typical internal gain assumptions in energy calculations are described. Heating and cooling loads from simulations using the DOE 2.1 computer code are compared for various internal gain inputs: typical hourly profiles, constant average profiles, and zero gain profiles. Prototype single-family-detached and multifamily-attached residential units are studied with various levels of insulation and infiltration. Small detached commercial buildings and attached zones in large commercial buildings are studied with various levels of internal gains. The results indicate that calculations of annual heating and cooling loads are sensitive to internal gains, but in most cases are relatively insensitive to hourly variations in internal gains.

  6. Effects of internal gain assumptions in building energy calculations

    NASA Astrophysics Data System (ADS)

    Christensen, C.; Perkins, R.

    The utilization of direct solar gains in buildings can be affected by operating profiles, such as schedules for internal gains, thermostat controls, and ventilation rates. Building energy analysis methods use various assumptions about these profiles. The effects of typical internal gain assumptions in energy calculations. Heating and cooling loads from simulations using the Department of Energy 2.1 computer code are compared for various internal-gain inputs: typical hourly profiles, constant average profiles, and zero gain profiles. Prototype single-family-detached and multi-family-attached residential units are studied with various levels of insulation and infiltration. Small detached commercial buildings and attached zones in large commercial buildings are studied with various levels of internal gains. The results indicate that calculations of annual heating and cooling loads are sensitive to internal gains, but in most cases are relatively insensitive to hourly variations in internal gains.

  7. Permanency of Gains for Children's Problem Solving Processes and Subabilities.

    ERIC Educational Resources Information Center

    Lundsteen, Sara W.; Wilson, John A. R.

    1979-01-01

    Results of an investigation of the permanency of gains in problem solving, listening, and abstract thinking among fifth graders are reported. Findings indicate that the experimental group with listening training shows greatest gains. (MH)

  8. Proprioceptive feedback determines visuomotor gain in Drosophila

    PubMed Central

    Bartussek, Jan; Lehmann, Fritz-Olaf

    2016-01-01

    Multisensory integration is a prerequisite for effective locomotor control in most animals. Especially, the impressive aerial performance of insects relies on rapid and precise integration of multiple sensory modalities that provide feedback on different time scales. In flies, continuous visual signalling from the compound eyes is fused with phasic proprioceptive feedback to ensure precise neural activation of wing steering muscles (WSM) within narrow temporal phase bands of the stroke cycle. This phase-locked activation relies on mechanoreceptors distributed over wings and gyroscopic halteres. Here we investigate visual steering performance of tethered flying fruit flies with reduced haltere and wing feedback signalling. Using a flight simulator, we evaluated visual object fixation behaviour, optomotor altitude control and saccadic escape reflexes. The behavioural assays show an antagonistic effect of wing and haltere signalling on visuomotor gain during flight. Compared with controls, suppression of haltere feedback attenuates while suppression of wing feedback enhances the animal’s wing steering range. Our results suggest that the generation of motor commands owing to visual perception is dynamically controlled by proprioception. We outline a potential physiological mechanism based on the biomechanical properties of WSM and sensory integration processes at the level of motoneurons. Collectively, the findings contribute to our general understanding how moving animals integrate sensory information with dynamically changing temporal structure. PMID:26909184

  9. GD SDR Automatic Gain Control Characterization Testing

    NASA Technical Reports Server (NTRS)

    Nappier, Jennifer M.; Briones, Janette C.

    2013-01-01

    The General Dynamics (GD) S-Band software defined radio (SDR) in the Space Communications and Navigation (SCAN) Testbed on the International Space Station (ISS) will provide experimenters an opportunity to develop and demonstrate experimental waveforms in space. The GD SDR platform and initial waveform were characterized on the ground before launch and the data will be compared to the data that will be collected during on-orbit operations. A desired function of the SDR is to estimate the received signal to noise ratio (SNR), which would enable experimenters to better determine on-orbit link conditions. The GD SDR does not have an SNR estimator, but it does have an analog and a digital automatic gain control (AGC). The AGCs can be used to estimate the SDR input power which can be converted into a SNR. Tests were conducted to characterize the AGC response to changes in SDR input power and temperature. This purpose of this paper is to describe the tests that were conducted, discuss the results showi ng how the AGCs relate to the SDR input power, and provide recommendations for AGC testing and characterization.

  10. GD SDR Automatic Gain Control Characterization Testing

    NASA Technical Reports Server (NTRS)

    Nappier, Jennifer M.; Briones, Janette C.

    2013-01-01

    The General Dynamics (GD) S-Band software defined radio (SDR) in the Space Communications and Navigation (SCAN) Testbed on the International Space Station (ISS) will provide experimenters an opportunity to develop and demonstrate experimental waveforms in space. The GD SDR platform and initial waveform were characterized on the ground before launch and the data will be compared to the data that will be collected during on-orbit operations. A desired function of the SDR is to estimate the received signal to noise ratio (SNR), which would enable experimenters to better determine on-orbit link conditions. The GD SDR does not have an SNR estimator, but it does have an analog and a digital automatic gain control (AGC). The AGCs can be used to estimate the SDR input power which can be converted into a SNR. Tests were conducted to characterize the AGC response to changes in SDR input power and temperature. This purpose of this paper is to describe the tests that were conducted, discuss the results showing how the AGCs relate to the SDR input power, and provide recommendations for AGC testing and characterization.

  11. Assessment of learning gains in a flipped biochemistry classroom.

    PubMed

    Ojennus, Deanna Dahlke

    2016-01-01

    The flipped classroom has become an increasingly popular pedagogical approach to teaching and learning. In this study, learning gains were assessed in a flipped biochemistry course and compared to gains in a traditional lecture. Although measured learning gains were not significantly different between the two courses, student perception of learning gains did differ and indicates a higher level of satisfaction with the flipped lecture format.

  12. Design gain characteristic of dual-pump fiber Raman amplifier

    NASA Astrophysics Data System (ADS)

    Chen, Jian; Zhang, Wei; Liu, Xiaoming; Peng, Jiangde; Zhou, BingKun

    2001-10-01

    To design gain characteristic of dual-pump fiber Raman amplifier, an effect optimal model is investigated under different conditions, such as maximal gain and minimal gain ripper. Impact of pumps interaction, pump wavelength selection, signals interaction and signal saturation are discussed.

  13. Assessment of Learning Gains in a Flipped Biochemistry Classroom

    ERIC Educational Resources Information Center

    Ojennus, Deanna Dahlke

    2016-01-01

    The flipped classroom has become an increasingly popular pedagogical approach to teaching and learning. In this study, learning gains were assessed in a flipped biochemistry course and compared to gains in a traditional lecture. Although measured learning gains were not significantly different between the two courses, student perception of…

  14. Who gains? Genetic and neurophysiological correlates of BMI gain upon college entry in women.

    PubMed

    Bauer, Lance O

    2014-11-01

    The present investigation examined P3 event-related electroencephalographic potentials and a short and selected list of addiction-related candidate gene single nucleotide polymorphisms (SNPs) within 84 female students, aged 18-20 yrs. The students were assigned to groups defined by the presence versus absence of a positive body mass index (BMI) change from the pre-college physical exam to the current day. Analyses revealed significantly greater P3 latencies and reduced P3 amplitudes during a response inhibition task among students who exhibited a BMI gain. BMI gain was also significantly associated with a ANKK1 SNP previously implicated in substance dependence risk. In logistic regression analyses, P3 latencies at the frontal electrode and this ANKK1 genotype correctly classified 71.1% of the students into the BMI groups. The present findings suggest that heritable indicators of impaired response inhibition can differentiate students who may be on a path toward an overweight or obese body mass.

  15. Muscle mass gain after resistance training is inversely correlated with trunk adiposity gain in postmenopausal women.

    PubMed

    Orsatti, Fábio L; Nahas, Eliana A P; Orsatti, Cláudio L; de Oliveira, Erick P; Nahas-Neto, Jorge; da Mota, Gustavo R; Burini, Roberto C

    2012-08-01

    The aim of this study was to evaluate alterations in trunk adiposity (TA) over 9 months of resistance training (RT) and associate these changes with the hypertrophy of muscle mass (MM) in postmenopausal women (PW). The investigation used a sample that consisted of 22 PW (44-69 years old). The group was subjected to RT (60-80% of 1 repetition maximum) for the total body 3 d · wk(-1). Body composition (dual-energy x-ray absorptiometry) and plasma levels of insulin-like growth factor-1 (IGF-1), follicle-stimulating hormone, E2 (Immulite system), and interleukin-6 (IL-6; enzyme-linked immunosorbent assay) were assessed at the beginning and end of the experiment. After RT, only women who acquired up to 5% TA gained MM, whereas women who acquired >5% TA exhibited increased IL-6 and no MM gain (p < 0.05). The ΔMM was negatively associated with time of menopause (r = -0.45, p < 0.05) and positively associated with baseline IGF-1 (r = 0.47, p < 0.05). Only ΔLE (leg extension) was negatively associated with baseline IL-6 (p < 0.05). Trunk adiposity growth (ΔTF, kilograms) was positively correlated with changes in IL-6 (r = 0.68, p < 0.05). The MM gain was negatively correlated with ΔTF (r = -0.63, p < 0.05) and changes in IL-6 (r = -0.73, p < 0.05). After adjusting all of the confounding variables, only baseline IGF-1 (positively) and changes in IL-6 (negatively) influenced MM, and only the increase in TA influenced IL-6. Our study suggests that increased levels of TA during RT increase IL-6 concentrations, which is a significant negative predictor of MM gain in PW.

  16. Are videogame training gains specific or general?

    PubMed Central

    Patterson, Michael D.

    2014-01-01

    Many recent studies using healthy adults document enhancements in perception and cognition from playing commercial action videogames (AVGs). Playing action games (e.g., Call of Duty, Medal of Honor) is associated with improved bottom-up lower-level information processing skills like visual-perceptual and attentional processes. One proposal states a general improvement in the ability to interpret and gather statistical information to predict future actions which then leads to better performance across different perceptual/attentional tasks. Another proposal claims all the tasks are separately trained in the AVGs because the AVGs and laboratory tasks contain similar demands. We review studies of action and non-AVGs to show support for the latter proposal. To explain transfer in AVGs, we argue that the perceptual and attention tasks share common demands with the trained videogames (e.g., multiple object tracking (MOT), rapid attentional switches, and peripheral vision). In non-AVGs, several studies also demonstrate specific, limited transfer. One instance of specific transfer is the specific enhancement to mental rotation after training in games with a spatial emphasis (e.g., Tetris). In contrast, the evidence for transfer is equivocal where the game and task do not share common demands (e.g., executive functioning). Thus, the “common demands” hypothesis of transfer not only characterizes transfer effects in AVGs, but also non-action games. Furthermore, such a theory provides specific predictions, which can help in the selection of games to train human cognition as well as in the design of videogames purposed for human cognitive and perceptual enhancement. Finally this hypothesis is consistent with the cognitive training literature where most post-training gains are for tasks similar to the training rather than general, non-specific improvements. PMID:24782722

  17. Are videogame training gains specific or general?

    PubMed

    Oei, Adam C; Patterson, Michael D

    2014-01-01

    Many recent studies using healthy adults document enhancements in perception and cognition from playing commercial action videogames (AVGs). Playing action games (e.g., Call of Duty, Medal of Honor) is associated with improved bottom-up lower-level information processing skills like visual-perceptual and attentional processes. One proposal states a general improvement in the ability to interpret and gather statistical information to predict future actions which then leads to better performance across different perceptual/attentional tasks. Another proposal claims all the tasks are separately trained in the AVGs because the AVGs and laboratory tasks contain similar demands. We review studies of action and non-AVGs to show support for the latter proposal. To explain transfer in AVGs, we argue that the perceptual and attention tasks share common demands with the trained videogames (e.g., multiple object tracking (MOT), rapid attentional switches, and peripheral vision). In non-AVGs, several studies also demonstrate specific, limited transfer. One instance of specific transfer is the specific enhancement to mental rotation after training in games with a spatial emphasis (e.g., Tetris). In contrast, the evidence for transfer is equivocal where the game and task do not share common demands (e.g., executive functioning). Thus, the "common demands" hypothesis of transfer not only characterizes transfer effects in AVGs, but also non-action games. Furthermore, such a theory provides specific predictions, which can help in the selection of games to train human cognition as well as in the design of videogames purposed for human cognitive and perceptual enhancement. Finally this hypothesis is consistent with the cognitive training literature where most post-training gains are for tasks similar to the training rather than general, non-specific improvements.

  18. Loss restlessness and gain calmness: durable effects of losses and gains on choice switching.

    PubMed

    Yechiam, Eldad; Zahavi, Gal; Arditi, Eli

    2015-08-01

    While the traditional conceptualization of the effect of losses focuses on bias in the subjective weight of losses compared with respective gains, some accounts suggest more global task-related effects of losses. Based on a recent attentional theory, we predicted a positive after-effect of losses on choice switching in later tasks. In two experimental studies, we found increased choice switching rates in tasks with losses compared to tasks with no losses. Additionally, this heightened shifting behavior was maintained in subsequent tasks that do not include losses, a phenomenon we refer to as "loss restlessness." Conversely, gains were found to have an opposite "calming" effect on choice switching. Surprisingly, the loss restlessness phenomenon was observed following an all-losses payoff regime but not after a task with symmetric mixed gains and losses. This suggests that the unresolved mental account following an all-losses regime increases search behavior. Potential implications to macro level phenomena, such as the leverage effect, are discussed.

  19. Fundamental limitations to gain enhancement in periodic media and waveguides.

    PubMed

    Grgić, Jure; Ott, Johan Raunkjær; Wang, Fengwen; Sigmund, Ole; Jauho, Antti-Pekka; Mørk, Jesper; Mortensen, N Asger

    2012-05-04

    A common strategy to compensate for losses in optical nanostructures is to add gain material in the system. By exploiting slow-light effects it is expected that the gain may be enhanced beyond its bulk value. Here we show that this route cannot be followed uncritically: inclusion of gain inevitably modifies the underlying dispersion law, and thereby may degrade the slow-light properties underlying the device operation and the anticipated gain enhancement itself. This degradation is generic; we demonstrate it for three different systems of current interest (coupled-resonator optical waveguides, Bragg stacks, and photonic crystal waveguides). Nevertheless, a small amount of added gain may be beneficial.

  20. Luminance-Chrominance Gain Equalizer Based on Bernstein Polynomials

    NASA Astrophysics Data System (ADS)

    Chutchavong, Vanvisa; Sangaroon, Ornlarp; Benjangkaprasert, Chawalit; Janchitrapongvej, Kanok

    This paper presents a linear luminance-chrominance gain equalizer for correcting the linear chrominance gain distortion in the color TV transmission system. The proposed gain equalizer was implemented based on Bernstein polynomials. As it is known that the Bernstein filter has flexible parameters to adjust the circuit performance for the best results. In addition, the modulated 20T sine-squared pulse test signal is generated for testing the performance of the proposed gain equalizer, which can be measured all three types of the linear chrominance distortions. As the results, the proposed gain equalizer is also proved to be efficient in equalizing both the low gain and the high gain chrominance distortions without degrading its phase characteristics.

  1. Gain and loss mechanisms in fluorocarbon plasmas

    NASA Astrophysics Data System (ADS)

    Nelson, Caleb Timothy

    Understanding dominant reaction channels for important gas-phase species in fluorocarbon plasmas is crucial to the ability to control surface evolution and morphology. In order to accomplish this goal a modified GEC reference ICP reactor is used in tandem with Fourier transform infrared spectroscopy (FTIR) to measure the densities of stable species. Integrated absorption cross-sections are presented for all fundamental bands in the 650 cm-1 to 2000 cm-1 region for C3F6, C4F 8, C3F8, C2F6, C2F 4, and CF4. The results show that although the absorption profile changes significantly, the integrated absorption cross-sections, with the exception of CF4, do not change significantly as gas temperature increases from 25°C to 200°C. However, the internal temperature of the absorbing species can be estimated from the rotational band maximum in most cases. Species densities obtained with the aforementioned cross-sections are used with a novel analysis technique to quantify gain and loss rates as functions of residence time, pressure, and deposited power. CF4, C2F6, C3F8, and C4F 10, share related production channels, which increase in magnitude as the plasma pressure, deposited power, or surface temperature are raised. CF 2 is primarily produced through a combination of surface production (the magnitude also increases with temperature) and electron impact dissociation of C2F4, while it is predominantly lost in the large reactor to gas-phase addition to form C2F4. Time-resolved FTIR results are used to measure a cross-section of 1.8x10-14 cm3/s for the reaction between CF2 radicals creating C2F4. Finally, C2F4 originates through the electron impact dissociation of c- C4F8. The loss process for C2F4 is undetermined, but the results indicate that it could occur on reactor surfaces. Neither the density of fluorine nor the ion flux to the chuck surface changes substantially with wall temperature. We show that increases in the deposition rate in a heated chamber are due to an

  2. Training Children in Pedestrian Safety: Distinguishing Gains in Knowledge from Gains in Safe Behavior

    PubMed Central

    McClure, Leslie A.

    2014-01-01

    Pedestrian injuries contribute greatly to child morbidity and mortality. Recent evidence suggests that training within virtual pedestrian environments may improve children’s street crossing skills, but may not convey knowledge about safety in street environments. We hypothesized that (a) children will gain pedestrian safety knowledge via videos/software/internet websites, but not when trained by virtual pedestrian environment or other strategies; (b) pedestrian safety knowledge will be associated with safe pedestrian behavior both before and after training; and (c) increases in knowledge will be associated with increases in safe behavior among children trained individually at streetside locations, but not those trained by means of other strategies. We analyzed data from a randomized controlled trial evaluating pedestrian safety training. We randomly assigned 240 children ages 7–8 to one of four training conditions: videos/software/internet, virtual reality (VR), individualized streetside instruction, or a no-contact control. Both virtual and field simulations of street crossing at 2-lane bi-directional mid-block locations assessed pedestrian behavior at baseline, post-training, and 6-month follow-up. Pedestrian knowledge was assessed orally on all three occasions. Children trained by videos/software/internet, and those trained individually, showed increased knowledge following training relative to children in the other groups (ps < 0.01). Correlations between pedestrian safety knowledge and pedestrian behavior were mostly non-significant. Correlations between change in knowledge and change in behavior from pre- to post-intervention also were non-significant, both for the full sample and within conditions. Children trained using videos/software/internet gained knowledge but did not change their behavior. Children trained individually gained in both knowledge and safer behavior. Children trained virtually gained in safer behavior but not knowledge. If VR is used

  3. Gain-of-Function Research: Ethical Analysis.

    PubMed

    Selgelid, Michael J

    2016-08-01

    Gain-of-function (GOF) research involves experimentation that aims or is expected to (and/or, perhaps, actually does) increase the transmissibility and/or virulence of pathogens. Such research, when conducted by responsible scientists, usually aims to improve understanding of disease causing agents, their interaction with human hosts, and/or their potential to cause pandemics. The ultimate objective of such research is to better inform public health and preparedness efforts and/or development of medical countermeasures. Despite these important potential benefits, GOF research (GOFR) can pose risks regarding biosecurity and biosafety. In 2014 the administration of US President Barack Obama called for a "pause" on funding (and relevant research with existing US Government funding) of GOF experiments involving influenza, SARS, and MERS viruses in particular. With announcement of this pause, the US Government launched a "deliberative process" regarding risks and benefits of GOFR to inform future funding decisions-and the US National Science Advisory Board for Biosecurity (NSABB) was tasked with making recommendations to the US Government on this matter. As part of this deliberative process the National Institutes of Health commissioned this Ethical Analysis White Paper, requesting that it provide (1) review and summary of ethical literature on GOFR, (2) identification and analysis of existing ethical and decision-making frameworks relevant to (i) the evaluation of risks and benefits of GOFR, (ii) decision-making about the conduct of GOF studies, and (iii) the development of US policy regarding GOFR (especially with respect to funding of GOFR), and (3) development of an ethical and decision-making framework that may be considered by NSABB when analyzing information provided by GOFR risk-benefit assessment, and when crafting its final recommendations (especially regarding policy decisions about funding of GOFR in particular). The ethical and decision-making framework

  4. Who Gains? Genetic and Neurophysiological Correlates of BMI Gain Upon College Entry in Women

    PubMed Central

    Bauer, Lance O.

    2014-01-01

    The present investigation examined P3 event-related electroencephalographic potentials and a short and selected list of addiction-related candidate gene single nucleotide polymorphisms (SNPs) within 84 female students, aged 18–20 yrs. The students were assigned to groups defined by the presence versus absence of a positive body mass index (BMI) change from the pre-college physical exam to the current day. Analyses revealed significantly greater P3 latencies and reduced P3 amplitudes during a response inhibition task among students who exhibited a BMI gain. BMI gain was also significantly associated with a ANKK1 SNP previously implicated in substance dependence risk. In logistic regression analyses, P3 latencies at the frontal electrode and this ANKK1 genotype correctly classified 71.1% of the students into the BMI groups. The present findings suggest that heritable indicators of impaired response inhibition can differentiate students who may be on a path toward an overweight or obese body mass. PMID:25049133

  5. Serotonin Affects Movement Gain Control in the Spinal Cord

    PubMed Central

    Glaser, Joshua I.; Deng, Linna; Thompson, Christopher K.; Stevenson, Ian H.; Wang, Qining; Hornby, Thomas George; Heckman, Charles J.; Kording, Konrad P.

    2014-01-01

    A fundamental challenge for the nervous system is to encode signals spanning many orders of magnitude with neurons of limited bandwidth. To meet this challenge, perceptual systems use gain control. However, whether the motor system uses an analogous mechanism is essentially unknown. Neuromodulators, such as serotonin, are prime candidates for gain control signals during force production. Serotonergic neurons project diffusely to motor pools, and, therefore, force production by one muscle should change the gain of others. Here we present behavioral and pharmaceutical evidence that serotonin modulates the input–output gain of motoneurons in humans. By selectively changing the efficacy of serotonin with drugs, we systematically modulated the amplitude of spinal reflexes. More importantly, force production in different limbs interacts systematically, as predicted by a spinal gain control mechanism. Psychophysics and pharmacology suggest that the motor system adopts gain control mechanisms, and serotonin is a primary driver for their implementation in force production. PMID:25232107

  6. Gainful Activity and Intimate Partner Aggression in Emerging Adulthood*

    PubMed Central

    Alvira-Hammond, Marta; Longmore, Monica A.; Manning, Wendy D.; Giordano, Peggy C.

    2014-01-01

    Although intimate partner aggression crosses social class boundaries, education and income are important predictors. Yet given that emerging adulthood is a transitional period, completed education and employment, as single measures, are not ideal indicators of socioeconomic status for young people. We examined associations between self-reports of gainful activity, defined as enrollment in school or full-time employment, and intimate partner aggression among young adults in dating, cohabiting, or married relationships (N=648). Both men and women's participation in gainful activity was negatively associated with aggression. We found that when neither partner was gainfully active, individuals reported higher frequency of physical aggression. In cases of gainful activity asymmetry, the gender of the gainfully active partner did not predict intimate partner aggression. Additionally, we found no evidence that the association between gainful activity and frequency of intimate partner aggression differed by union type. PMID:25309829

  7. The effects of neural gain on attention and learning

    PubMed Central

    Eldar, Eran; Cohen, Jonathan D.; Niv, Yael

    2013-01-01

    Attention is commonly thought to be manifest through local variations in neural gain. However, what would be the effects of brain-wide changes in gain? Here, we hypothesize that global fluctuations in gain modulate the breadth of attention, and thus, the degree to which processing is focused on aspects of the environment to which one is predisposed to attend. In accordance with this hypothesis, we show that measures of pupil diameter, which are thought to track levels of LC-NE activity and neural gain, are correlated with the degree to which learning is focused on stimulus dimensions that individual human participants are more predisposed to process. In support of our interpretation of this effect in terms of global changes in gain, we further show that the measured pupillary and behavioral variables are strongly correlated with global changes in the strength and clustering of functional connectivity, as brain-wide fluctuations of gain would predict. PMID:23770566

  8. Non-semantic contributions to "semantic" redundancy gain.

    PubMed

    Shepherdson, Peter; Miller, Jeff

    2016-01-01

    Recently, two groups of researchers have reported redundancy gains (enhanced performance with multiple, redundant targets) in tasks requiring semantic categorization. Here we report two experiments aimed at determining whether the gains found by one of these groups resulted from some form of semantic coactivation. We asked undergraduate psychology students to complete choice RT tasks requiring the semantic categorization of visually presented words, and compared performance with redundant targets from the same semantic category to performance with redundant targets from different semantic categories. If the redundancy gains resulted from the combination of information at a semantic level, they should have been greater in the former than the latter situation. However, our results showed no significant differences in redundancy gain (for latency and accuracy) between same-category and different-category conditions, despite gains appearing in both conditions. Thus, we suggest that redundancy gain in the semantic categorization task may result entirely from statistical facilitation or combination of information at non-semantic levels.

  9. Use of a photonic crystal for optical amplifier gain control

    DOEpatents

    Lin, Shawn-Yu; Fleming, James G.; El-Kady, Ihab

    2006-07-18

    An optical amplifier having a uniform gain profile uses a photonic crystal to tune the density-of-states of a gain medium so as to modify the light emission rate between atomic states. The density-of-states of the gain medium is tuned by selecting the size, shape, dielectric constant, and spacing of a plurality of microcavity defects in the photonic crystal. The optical amplifier is particularly useful for the regeneration of DWDM signals in long optical fibers.

  10. Spatial dynamics, thermalization, and gain clamping in a photon condensate

    NASA Astrophysics Data System (ADS)

    Keeling, Jonathan; Kirton, Peter

    2016-01-01

    We study theoretically the effects of pump-spot size and location on photon condensates. By exploring the inhomogeneous molecular excitation fraction, we make clear the relation between spatial equilibration, gain clamping, and thermalization in a photon condensate. This provides a simple understanding of several recent experimental results. We find that as thermalization breaks down, gain clamping is imperfect, leading to "transverse spatial hole burning" and multimode condensation. This opens the possibility of engineering the gain profile to control the condensate structure.

  11. Insulin sensitivity and regional fat gain in response to overfeeding

    PubMed Central

    Votruba, S. B.; Jensen, M. D.

    2013-01-01

    Although insulin resistance and Type 2 diabetes are associated with upper body fat distribution, it is unknown whether insulin resistance predisposes to upper body fat gain or whether upper body fat gain causes insulin resistance. Our objective was to determine whether insulin sensitivity predicts abdominal (subcutaneous and/or visceral) fat gain in normal weight adults. Twenty-eight (15 men) lean (BMI = 22.1±2.5 kg/m2), healthy adults underwent ~8 weeks of overfeeding to gain ~4 kg fat. Body composition was assessed before and after overfeeding using DXA and abdominal CT to measure total and regional (visceral, abdominal, and lower body subcutaneous) fat gain. We assessed insulin sensitivity with an IV glucose tolerance test and the 24h insulin area-under-the-curve(AUC). We found a wide range of insulin sensitivity and a relatively narrow range of body fat distribution in this normal weight cohort. Participants gained 3.8±1.7 kg of body fat (4.6±2.2 kg body weight). The baseline 24h AUC of insulin concentration was positively correlated with percent body fat (r=0.43, p<0.05). The contribution of leg fat gain to total fat gain ranged from 29–79%, while the contributions of abdominal subcutaneous fat and visceral fat gain to total fat gain ranged from 17–69% and −5–22%, respectively. Baseline insulin sensitivity, whether measured by an IVGTT or the 24h AUC insulin Si, did not predict upper body subcutaneous or visceral fat gain in response to overfeeding. We conclude that reduced insulin sensitivity is not an obligate precursor to upper body fat gain. PMID:21127472

  12. If there is dissipation the particle can gain energy

    NASA Astrophysics Data System (ADS)

    Egydio de Carvalho, R.

    2015-10-01

    In this work, we summarize two different mechanisms to gain energy from the presence of dissipation in a time-dependent non-linear system. The particles can gain energy, in the average, from two different scenarios: i) for very week dissipation with the creation of an attractor with high velocity, and ii) in the opposite limit, for very strong dissipation, the particles can also gain energy from a boundary crisis. From the thermodynamic viewpoint both results are totally acceptable.

  13. Fluerics 42: Some Commonly Used Laminar Fluidic Gain Blocks

    DTIC Science & Technology

    1982-09-01

    programmable calculator . Outputs from this program and flows and staged gain. Also available is the net gain and the bandwidth at 90 deg of phase shift. Several examples of this program are given to cover multiple-stage gain blocks. As an example of the utility of the program, a step-by-step tradeoff study is presented for the Massachusetts Institute of Technology fluidic servovalve, for which an attempt is made to maximize bandwidth and minimize leakage

  14. Astronomers Gain Clues About Fundamental Physics

    NASA Astrophysics Data System (ADS)

    2005-12-01

    An international team of astronomers has looked at something very big -- a distant galaxy -- to study the behavior of things very small -- atoms and molecules -- to gain vital clues about the fundamental nature of our entire Universe. The team used the National Science Foundation's Robert C. Byrd Green Bank Telescope (GBT) to test whether the laws of nature have changed over vast spans of cosmic time. The Green Bank Telescope The Robert C. Byrd Green Bank Telescope CREDIT: NRAO/AUI/NSF (Click on image for GBT gallery) "The fundamental constants of physics are expected to remain fixed across space and time; that's why they're called constants! Now, however, new theoretical models for the basic structure of matter indicate that they may change. We're testing these predictions." said Nissim Kanekar, an astronomer at the National Radio Astronomy Observatory (NRAO), in Socorro, New Mexico. So far, the scientists' measurements show no change in the constants. "We've put the most stringent limits yet on some changes in these constants, but that's not the end of the story," said Christopher Carilli, another NRAO astronomer. "This is the exciting frontier where astronomy meets particle physics," Carilli explained. The research can help answer fundamental questions about whether the basic components of matter are tiny particles or tiny vibrating strings, how many dimensions the Universe has, and the nature of "dark energy." The astronomers were looking for changes in two quantities: the ratio of the masses of the electron and the proton, and a number physicists call the fine structure constant, a combination of the electron charge, the speed of light and the Planck constant. These values, considered fundamental physical constants, once were "taken as time independent, with values given once and forever" said German particle physicist Christof Wetterich. However, Wetterich explained, "the viewpoint of modern particle theory has changed in recent years," with ideas such as

  15. Sudden gains in two psychotherapies for posttraumatic stress disorder.

    PubMed

    König, Julia; Karl, Regina; Rosner, Rita; Butollo, Willi

    2014-09-01

    We examined sudden, large, and stable shifts in symptoms from one therapy session to the next in two treatments for posttraumatic stress disorder (PTSD). Shifts in a positive direction (sudden gains) have so far been more frequently analyzed than those in a negative direction (sudden losses). We analyzed data from 102 outpatients suffering from PTSD who received either a cognitive-behavioral or a Gestalt-based intervention. Sudden gains, at 22.5%, were more frequent than sudden losses (3.9% of patients). Participants who had experienced sudden gains had lower PTSD scores at posttreatment, but not at the 6-month follow-up. As sudden losses were so rare, they were not analyzed statistically. Sudden gains accounted for 52% of overall treatment gains or 26% of overall change in a positive direction. Among very successful patients, those with sudden gains were overrepresented, but in absolute terms, there were as many patients without sudden gains in this group. There was no connection between sudden gains and type of intervention or depressive symptoms. Sudden gains and sudden losses occurred in our sample of PTSD patients, but in the light of current results, their clinical importance seems to be limited.

  16. Absolute gain measurement by the image method under mismatched condition

    NASA Technical Reports Server (NTRS)

    Lee, Richard Q.; Baddour, Maurice F.

    1987-01-01

    Purcell's image method for measuring the absolute gain of an antenna is particularly attractive for small test antennas. The method is simple to use and utilizes only one antenna with a reflecting plane to provide an image for the receiving antenna. However, the method provides accurate results only if the antenna is matched to its waveguide. In this paper, a waveguide junction analysis is developed to determine the gain of an antenna under mismatched condition. Absolute gain measurements for two standard gain horn antennas have been carried out. Experimental results agree closely with published data.

  17. Modest Visceral Fat Gain Causes Endothelial Dysfunction In Healthy Humans

    PubMed Central

    Romero-Corral, Abel; Sert-Kuniyoshi, Fatima H.; Sierra-Johnson, Justo; Orban, Marek; Gami, Apoor; Davison, Diane; Singh, Prachi; Pusalavidyasagar, Snigdha; Huyber, Christine; Votruba, Susanne; Lopez-Jimenez, Francisco; Jensen, Michael D.; Somers, Virend K.

    2014-01-01

    Objective This study sought to determine the impact of fat gain and its distribution on endothelial function in lean healthy humans. Background Endothelial dysfunction has been identified as an independent predictor of cardiovascular events. Whether fat gain impairs endothelial function is unknown. Methods A randomized controlled study to assess the effects of fat gain on endothelial function. We recruited 43 normal weight healthy volunteers (mean age 29 years; 18 women). Subjects were assigned to gain weight (approximately 4 kg) (n=35) or to maintain weight (n=8). Endothelial function (brachial artery flow mediated dilation -FMD) was measured at baseline, after fat gain (8 weeks) and after weight loss (16 weeks) for fat-gainers and at baseline and follow-up (8 weeks) for weight-maintainers. Body composition was measured by DXA and abdominal CT scans. Results After an average weight gain of 4.1 kg, fat-gainers significantly increased their total, visceral and subcutaneous fat. Blood pressure and overnight polysomnography did not change after fat gain or loss. FMD remained unchanged in weight-maintainers. FMD decreased in fat-gainers (9.1 ± 3% vs. 7.8 ± 3.2%, p =0.003), but recovered to baseline when subjects shed the gained weight. There was a significant correlation between the decrease in FMD and the increase in visceral fat gain (rho = −0.42, p=0.004), but not with subcutaneous fat gain (rho = −0.22, p=0.15). Conclusions In normal weight healthy young subjects, modest fat gain results in impaired endothelial function, even in the absence of changes in blood pressure. Endothelial function recovers after weight loss. Increased visceral rather than subcutaneous fat predicts endothelial dysfunction. PMID:20705223

  18. Distribution of lifespan gain from primary prevention intervention

    PubMed Central

    Finegold, Judith A; Shun-Shin, Matthew J; Cole, Graham D; Zaman, Saman; Maznyczka, Annette; Zaman, Sameer; Al-Lamee, Rasha; Ye, Siqin; Francis, Darrel P

    2016-01-01

    Objective When advising patients about possible initiation of primary prevention treatment, clinicians currently do not have information on expected impact on lifespan, nor how much this increment differs between individuals. Methods First, UK cardiovascular and non-cardiovascular mortality data were used to calculate the mean lifespan gain from an intervention (such as a statin) that reduces cardiovascular mortality by 30%. Second, a new method was developed to calculate the probability distribution of lifespan gain. Third, we performed a survey in three UK cities on 11 days between May–June 2014 involving 396 participants (mean age 40 years, 55% male) to assess how individuals evaluate potential benefit from primary prevention therapies. Results Among numerous identical patients, the lifespan gain, from an intervention that reduces cardiovascular mortality by 30%, is concentrated within an unpredictable minority. For example, men aged 50 years with national average cardiovascular risk have mean lifespan gain of 7 months. However, 93% of these identical individuals gain no lifespan, while the remaining 7% gain a mean of 99 months. Many survey respondents preferred a chance of large lifespan gain to the equivalent life expectancy gain given as certainty. Indeed, 33% preferred a 2% probability of 10 years to fivefold more gain, expressed as certainty of 1 year. Conclusions People who gain lifespan from preventative therapy gain far more than the average for their risk stratum, even if perfectly defined. This may be important in patient decision-making. Looking beyond mortality reduction alone from preventative therapy, the benefits are likely to be even larger. PMID:27042321

  19. 20 CFR 416.910 - Meaning of substantial gainful activity.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ....910 Section 416.910 Employees' Benefits SOCIAL SECURITY ADMINISTRATION SUPPLEMENTAL SECURITY INCOME FOR THE AGED, BLIND, AND DISABLED Determining Disability and Blindness Definition of Disability § 416.910 Meaning of substantial gainful activity. Substantial gainful activity means work that—...

  20. 26 CFR 1.1202-1 - Deduction for capital gains.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... asset has been held. Nevertheless, the net short-term capital gain or loss and the net long-term capital... exceeds the net short-term capital loss, 50 percent of the amount of the excess is allowable as a... under section 1202 in the case of an estate or trust, any long-term or short-term capital gains...

  1. Problems with IQ Gains: The Huge Vocabulary Gap

    ERIC Educational Resources Information Center

    Flynn, James R.

    2010-01-01

    Despite Kaufman, Raven's Progressive Matrices and the Wechsler subtest Similarities are tests whose gains call for special explanation. The spread of "scientific spectacles" is the key, but its explanatory potential has been exhausted. Three trends force us to look elsewhere: (a) gains on Wechsler subtests such as Picture Arrangement,…

  2. Optimal deployment of attentional gain during fine discriminations.

    PubMed

    Scolari, Miranda; Byers, Anna; Serences, John T

    2012-05-30

    Most models assume that top-down attention enhances the gain of sensory neurons tuned to behaviorally relevant stimuli (on-target gain). However, theoretical work suggests that when targets and distracters are highly similar, attention should enhance the gain of neurons that are tuned away from the target, because these neurons better discriminate neighboring features (off-target gain). While it is established that off-target neurons support difficult fine discriminations, it is unclear if top-down attentional gain can be optimally applied to informative off-target sensory neurons or if gain is always applied to on-target neurons, regardless of task demands. To test the optimality of attentional gain in human visual cortex, we used functional magnetic resonance imaging and an encoding model to estimate the response profile across a set of hypothetical orientation-selective channels during a difficult discrimination task. The results suggest that top-down attention can adaptively modulate off-target neural populations, but only when the discriminanda are precisely specified in advance. Furthermore, logistic regression revealed that activation levels in off-target orientation channels predicted behavioral accuracy on a trial-by-trial basis. Overall, these data suggest that attention does not only increase the gain of sensory-evoked responses, but may bias population response profiles in an optimal manner that respects both the tuning properties of sensory neurons and the physical characteristics of the stimulus array.

  3. Optimal deployment of attentional gain during fine discriminations

    PubMed Central

    Scolari, Miranda; Byers, Anna; Serences, John T.

    2012-01-01

    Most models assume that top-down attention enhances the gain of sensory neurons tuned to behaviorally-relevant stimuli (on-target gain). However, theoretical work suggests that when targets and distracters are highly similar, attention should enhance the gain of neurons that are tuned away from the target, because these neurons better discriminate neighboring features (off-target gain). While it is established that off-target neurons support difficult fine discriminations, it is unclear if top-down attentional gain can be optimally applied to informative off-target sensory neurons or if gain is always applied to on-target neurons, irrespective of task demands. To test the optimality of attentional gain in human visual cortex, we used fMRI and an encoding model to estimate the response profile across a set of hypothetical orientation-selective channels during a difficult discrimination task. The results suggest that top-down attention can adaptively modulate off-target neural populations, but only when the discriminanda are precisely specified in advance. Furthermore, logistic regression revealed that activation levels in off-target orientation channels predicted behavioral accuracy on a trial-by-trial basis. Overall, these data suggest that attention does not always increase the gain of sensory-evoked responses, but instead may bias population response profiles in an optimal manner that respects both the tuning properties of sensory neurons and the physical characteristics of the stimulus array. PMID:22649250

  4. Optimal gains for a single polar orbiting satellite

    NASA Technical Reports Server (NTRS)

    Banfield, Don; Ingersoll, A. P.; Keppenne, C. L.

    1993-01-01

    Gains are the spatial weighting of an observation in its neighborhood versus the local values of a model prediction. They are the key to data assimilation, as they are the direct measure of how the data are used to guide the model. As derived in the broad context of data assimilation by Kalman and in the context of meteorology, for example, by Rutherford, the optimal gains are functions of the prediction error covariances between the observation and analysis points. Kalman introduced a very powerful technique that allows one to calculate these optimal gains at the time of each observation. Unfortunately, this technique is both computationally expensive and often numerically unstable for dynamical systems of the magnitude of meteorological models, and thus is unsuited for use in PMIRR data assimilation. However, the optimal gains as calculated by a Kalman filter do reach a steady state for regular observing patterns like that of a satellite. In this steady state, the gains are constants in time, and thus could conceivably be computed off-line. These steady-state Kalman gains (i.e., Wiener gains) would yield optimal performance without the computational burden of true Kalman filtering. We proposed to use this type of constant-in-time Wiener gain for the assimilation of data from PMIRR and Mars Observer.

  5. A variable-gain output feedback control design methodology

    NASA Technical Reports Server (NTRS)

    Halyo, Nesim; Moerder, Daniel D.; Broussard, John R.; Taylor, Deborah B.

    1989-01-01

    A digital control system design technique is developed in which the control system gain matrix varies with the plant operating point parameters. The design technique is obtained by formulating the problem as an optimal stochastic output feedback control law with variable gains. This approach provides a control theory framework within which the operating range of a control law can be significantly extended. Furthermore, the approach avoids the major shortcomings of the conventional gain-scheduling techniques. The optimal variable gain output feedback control problem is solved by embedding the Multi-Configuration Control (MCC) problem, previously solved at ICS. An algorithm to compute the optimal variable gain output feedback control gain matrices is developed. The algorithm is a modified version of the MCC algorithm improved so as to handle the large dimensionality which arises particularly in variable-gain control problems. The design methodology developed is applied to a reconfigurable aircraft control problem. A variable-gain output feedback control problem was formulated to design a flight control law for an AFTI F-16 aircraft which can automatically reconfigure its control strategy to accommodate failures in the horizontal tail control surface. Simulations of the closed-loop reconfigurable system show that the approach produces a control design which can accommodate such failures with relative ease. The technique can be applied to many other problems including sensor failure accommodation, mode switching control laws and super agility.

  6. Sustaining Student Gains from Online On-Demand Professional Development

    ERIC Educational Resources Information Center

    Shaha, Steven H.; Glassett, Kelly; Copas, Aimee

    2015-01-01

    A multi-State, quasi-experimental study was conducted as a longitudinal, two-year follow-up of participation in an online, on-demand professional development (PD) program. The purpose was to ascertain whether student gains were sustained in a second year of PD participation. Data verified gains in Year 1 versus Pre-PD baseline, with continued…

  7. Validity of Sudden Gains in Acute Phase Treatment of Depression

    ERIC Educational Resources Information Center

    Vittengl, Jeffrey R.; Clark, Lee Anna; Jarrett, Robin B.

    2005-01-01

    The authors examined the validity of sudden gains identified with T. Z. Tang and R. J. DeRubeis's (1999) method in 2 clinical data sets that involved treatment of major depressive disorder (N=227). Sudden gains replicated among self- and clinician reports of depressive symptoms and predicted better psychosocial functioning at the acute phase…

  8. Behavioral Treatment Approaches to Prevent Weight Gain Following Smoking Cessation.

    ERIC Educational Resources Information Center

    Grinstead, Olga A.

    Personality and physiological, cognitive, and environmental factors have all been suggested as critical variables in smoking cessation and relapse. Weight gain and the fear of weight gain after smoking cessation may also prevent many smokers from quitting. A sample of 45 adult smokers participated in a study in which three levels of preventive…

  9. Investigating the wavelength dependency of dot gain in color print

    NASA Astrophysics Data System (ADS)

    Namedanian, Mahziar; Gooran, Sasan; Nyström, Daniel

    2011-01-01

    By separating the optical dot gain from the physical dot gain, it is possible to study different behaviors of color inks on different papers. In this study we are investigating the dependency of dot gain and wavelength in color print. Microscopic images have been used to separate optical and physical dot gain from each other. The optical behavior of primary color inks in different absorbing wavelength bands has been studied. It has been illustrated that the light scattering in the paper is wavelength independent, and therefore the Point Spread Function which indicates the probability of light scattering of the paper does not change in visible wavelengths (380 nm -700 nm). We have shown that it is possible to separate two printed color inks on one specific wavelength, due to the filtering behavior of the color inks. By considering the fact that light scattering in the paper is wavelength independent, it was possible to separately analyze the dot gain of each color.

  10. Insulin therapy and type 2 diabetes: management of weight gain.

    PubMed

    McFarlane, Samy I

    2009-10-01

    The potential for insulin-related weight gain in patients with type 2 diabetes presents a therapeutic dilemma and frequently leads to delays in the initiation of insulin therapy. It also poses considerable challenges when treatment is intensified. Addressing insulin-related weight gain is highly relevant to the prevention of metabolic and cardiovascular consequences in this high-risk population with type 2 diabetes. In addition to lifestyle changes (eg, diet and exercise) and available medical interventions to minimize the risk of weight gain with insulin treatment, familiarity with the weight gain patterns of different insulins may help deal with this problem. The use of basal insulin analogs may offer advantages over conventional human insulin preparations in terms of more physiologic time-action profiles, reduced risk of hypoglycemia, and reduced weight gain.

  11. Slow-light-enhanced gain in active photonic crystal waveguides.

    PubMed

    Ek, Sara; Lunnemann, Per; Chen, Yaohui; Semenova, Elizaveta; Yvind, Kresten; Mork, Jesper

    2014-09-30

    Passive photonic crystals have been shown to exhibit a multitude of interesting phenomena, including slow-light propagation in line-defect waveguides. It was suggested that by incorporating an active material in the waveguide, slow light could be used to enhance the effective gain of the material, which would have interesting application prospects, for example enabling ultra-compact optical amplifiers for integration in photonic chips. Here we experimentally investigate the gain of a photonic crystal membrane structure with embedded quantum wells. We find that by solely changing the photonic crystal structural parameters, the maximum value of the gain coefficient can be increased compared with a ridge waveguide structure and at the same time the spectral position of the peak gain be controlled. The experimental results are in qualitative agreement with theory and show that gain values similar to those realized in state-of-the-art semiconductor optical amplifiers should be attainable in compact photonic integrated amplifiers.

  12. Aircraft nonlinear optimal control using fuzzy gain scheduling

    NASA Astrophysics Data System (ADS)

    Nusyirwan, I. F.; Kung, Z. Y.

    2016-10-01

    Fuzzy gain scheduling is a common solution for nonlinear flight control. The highly nonlinear region of flight dynamics is determined throughout the examination of eigenvalues and the irregular pattern of root locus plots that show the nonlinear characteristic. By using the optimal control for command tracking, the pitch rate stability augmented system is constructed and the longitudinal flight control system is established. The outputs of optimal control for 21 linear systems are fed into the fuzzy gain scheduler. This research explores the capability in using both optimal control and fuzzy gain scheduling to improve the efficiency in finding the optimal control gains and to achieve Level 1 flying qualities. The numerical simulation work is carried out to determine the effectiveness and performance of the entire flight control system. The simulation results show that the fuzzy gain scheduling technique is able to perform in real time to find near optimal control law in various flying conditions.

  13. Slow-light-enhanced gain in active photonic crystal waveguides

    NASA Astrophysics Data System (ADS)

    Ek, Sara; Lunnemann, Per; Chen, Yaohui; Semenova, Elizaveta; Yvind, Kresten; Mork, Jesper

    2014-09-01

    Passive photonic crystals have been shown to exhibit a multitude of interesting phenomena, including slow-light propagation in line-defect waveguides. It was suggested that by incorporating an active material in the waveguide, slow light could be used to enhance the effective gain of the material, which would have interesting application prospects, for example enabling ultra-compact optical amplifiers for integration in photonic chips. Here we experimentally investigate the gain of a photonic crystal membrane structure with embedded quantum wells. We find that by solely changing the photonic crystal structural parameters, the maximum value of the gain coefficient can be increased compared with a ridge waveguide structure and at the same time the spectral position of the peak gain be controlled. The experimental results are in qualitative agreement with theory and show that gain values similar to those realized in state-of-the-art semiconductor optical amplifiers should be attainable in compact photonic integrated amplifiers.

  14. Adaptive gain and filtering circuit for a sound reproduction system

    NASA Technical Reports Server (NTRS)

    Engebretson, A. Maynard (Inventor); O'Connell, Michael P. (Inventor)

    1998-01-01

    Adaptive compressive gain and level dependent spectral shaping circuitry for a hearing aid include a microphone to produce an input signal and a plurality of channels connected to a common circuit output. Each channel has a preset frequency response. Each channel includes a filter with a preset frequency response to receive the input signal and to produce a filtered signal, a channel amplifier to amplify the filtered signal to produce a channel output signal, a threshold register to establish a channel threshold level, and a gain circuit. The gain circuit increases the gain of the channel amplifier when the channel output signal falls below the channel threshold level and decreases the gain of the channel amplifier when the channel output signal rises above the channel threshold level. A transducer produces sound in response to the signal passed by the common circuit output.

  15. Relationship Between Optimal Gain and Coherence Zone in Flight Simulation

    NASA Technical Reports Server (NTRS)

    Gracio, Bruno Jorge Correia; Pais, Ana Rita Valente; vanPaassen, M. M.; Mulder, Max; Kely, Lon C.; Houck, Jacob A.

    2011-01-01

    In motion simulation the inertial information generated by the motion platform is most of the times different from the visual information in the simulator displays. This occurs due to the physical limits of the motion platform. However, for small motions that are within the physical limits of the motion platform, one-to-one motion, i.e. visual information equal to inertial information, is possible. It has been shown in previous studies that one-to-one motion is often judged as too strong, causing researchers to lower the inertial amplitude. When trying to measure the optimal inertial gain for a visual amplitude, we found a zone of optimal gains instead of a single value. Such result seems related with the coherence zones that have been measured in flight simulation studies. However, the optimal gain results were never directly related with the coherence zones. In this study we investigated whether the optimal gain measurements are the same as the coherence zone measurements. We also try to infer if the results obtained from the two measurements can be used to differentiate between simulators with different configurations. An experiment was conducted at the NASA Langley Research Center which used both the Cockpit Motion Facility and the Visual Motion Simulator. The results show that the inertial gains obtained with the optimal gain are different than the ones obtained with the coherence zone measurements. The optimal gain is within the coherence zone.The point of mean optimal gain was lower and further away from the one-to-one line than the point of mean coherence. The zone width obtained for the coherence zone measurements was dependent on the visual amplitude and frequency. For the optimal gain, the zone width remained constant when the visual amplitude and frequency were varied. We found no effect of the simulator configuration in both the coherence zone and optimal gain measurements.

  16. Strengthening the Gluteus Medius Using Various Bodyweight and Resistance Exercises

    PubMed Central

    Tufano, James J.; Golas, Artur; Petr, Miroslav

    2016-01-01

    ABSTRACT THE GLUTEUS MEDIUS (Gmed) IS AN IMPORTANT MUSCLE AND, IF WEAK, CAN CAUSE KNEE, HIP, OR LOWER-BACK PATHOLOGIES. THIS ARTICLE REVIEWS METHODS OF Gmed STRENGTH ASSESSMENT, PROVIDES EXERCISES THAT TARGET THE Gmed BASED ON ELECTROMYOGRAPHY, PRESENTS HOW TO IMPLEMENT Gmed STRENGTHENING IN HEAVY RESISTANCE TRAINING PROGRAMS, AND EXPLAINS THE IMPORTANCE OF INCLUDING THESE EXERCISES IN THESE PROGRAMS. PMID:27340373

  17. Gain-switched pulses from InGaAs ridge-quantum-well lasers limited by intrinsic dynamical gain suppression.

    PubMed

    Chen, Shaoqiang; Yoshita, Masahiro; Ito, Takashi; Mochizuki, Toshimitsu; Akiyama, Hidefumi; Yokoyama, Hiroyuki

    2013-03-25

    Gain-switched pulses of InGaAs double-quantum-well lasers fabricated from identical epitaxial laser wafers were measured under both current injection and optical pumping conditions. The shortest output pulse widths were nearly identical (about 40 ps) both for current injection and optical pumping; this result attributed the dominant pulse-width limitation factor to the intrinsic gain properties of the lasers. We quantitatively compared the experimental results with theoretical calculations based on rate equations incorporating gain nonlinearities. Close consistency between the experimental data and the calculations was obtained only when we assumed a dynamically suppressed gain value deviated from the steady-state gain value supported by standard microscopic theories.

  18. Gain Scheduling for the Orion Launch Abort Vehicle Controller

    NASA Technical Reports Server (NTRS)

    McNamara, Sara J.; Restrepo, Carolina I.; Madsen, Jennifer M.; Medina, Edgar A.; Proud, Ryan W.; Whitley, Ryan J.

    2011-01-01

    One of NASAs challenges for the Orion vehicle is the control system design for the Launch Abort Vehicle (LAV), which is required to abort safely at any time during the atmospheric ascent portion of ight. The focus of this paper is the gain design and scheduling process for a controller that covers the wide range of vehicle configurations and flight conditions experienced during the full envelope of potential abort trajectories from the pad to exo-atmospheric flight. Several factors are taken into account in the automation process for tuning the gains including the abort effectors, the environmental changes and the autopilot modes. Gain scheduling is accomplished using a linear quadratic regulator (LQR) approach for the decoupled, simplified linear model throughout the operational envelope in time, altitude and Mach number. The derived gains are then implemented into the full linear model for controller requirement validation. Finally, the gains are tested and evaluated in a non-linear simulation using the vehicles ight software to ensure performance requirements are met. An overview of the LAV controller design and a description of the linear plant models are presented. Examples of the most significant challenges with the automation of the gain tuning process are then discussed. In conclusion, the paper will consider the lessons learned through out the process, especially in regards to automation, and examine the usefulness of the gain scheduling tool and process developed as applicable to non-Orion vehicles.

  19. Modifiable predictors associated with having a gestational weight gain goal.

    PubMed

    Tovar, Alison; Guthrie, Lauren B; Platek, Deborah; Stuebe, Alison; Herring, Sharon J; Oken, Emily

    2011-10-01

    The goal of this paper was to determine predictors of having a weight gain goal in early pregnancy. In 2008, we administered a 48-item survey to 249 pregnant women attending obstetric visits. We examined predictors of women having a goal concordant or discordant with 1990 Institute of Medicine (IOM) guidelines, vs. no goal, using binary and multinomial logistic regression. Of the 292 respondents, 116 (40%) had no gestational weight gain goal, 112 (39%) had a concordant goal and 61 (21%) had a goal discordant with IOM guidelines. Predictors of a guideline-concordant goal, vs. no goal, included sugar sweetened beverage consumption < vs. ≥ 1 serving per week (OR = 2.4, 95%CI: 1.1, 5.7), physical activity ≥ vs. <2.5 h per week (OR = 3.6, 95%CI: 1.7, 7.5), agreeing that 'I tried to keep weight down not to look pregnant' (OR = 14.3, 95%CI: 1.4, 140.5). Other predictors only of having a discordant goal (vs. no goal) included agreeing that 'as long as I am eating well, I don't care how much I gain' (OR = 0.3, 95%CI: 0.2, 0.8) and agreeing that 'if I gain too much weight one month, I try to keep from gaining the next' (OR = 4.1, 95%CI: 1.6, 10.4). Women whose doctors recommended weight gains consistent with IOM guidelines were more likely to have a concordant goal (vs. no goal) (OR = 5.3, 95%CI: 1.5, 18.6). Engaging in healthy behaviors and having health providers offer IOM weight gain recommendations may increase the likelihood of having a concordant gestational weight gain goal, which, in turn, is predictive of actual weight gains that fall within IOM guidelines.

  20. LPV Controller Interpolation for Improved Gain-Scheduling Control Performance

    NASA Technical Reports Server (NTRS)

    Wu, Fen; Kim, SungWan

    2002-01-01

    In this paper, a new gain-scheduling control design approach is proposed by combining LPV (linear parameter-varying) control theory with interpolation techniques. The improvement of gain-scheduled controllers can be achieved from local synthesis of Lyapunov functions and continuous construction of a global Lyapunov function by interpolation. It has been shown that this combined LPV control design scheme is capable of improving closed-loop performance derived from local performance improvement. The gain of the LPV controller will also change continuously across parameter space. The advantages of the newly proposed LPV control is demonstrated through a detailed AMB controller design example.

  1. Achieving improved cycle efficiency via pressure gain combustors

    SciTech Connect

    Gemmen, R.S.; Janus, M.C.; Richards, G.A.; Norton, T.S.; Rogers, W.A.

    1995-04-01

    As part of the Department of Energy`s Advanced Gas Turbine Systems Program, an investigation is being performed to evaluate ``pressure gain`` combustion systems for gas turbine applications. This paper presents experimental pressure gain and pollutant emission data from such combustion systems. Numerical predictions for certain combustor geometries are also presented. It is reported that for suitable aerovalved pulse combustor geometries studied experimentally, an overall combustor pressure gain of nearly 1 percent can be achieved. It is also shown that for one combustion system operating under typical gas turbine conditions, NO{sub x} and CO emmissions, are about 30 ppmv and 8 ppmv, respectively.

  2. Symmetry breaking and multipeaked solitons in inhomogeneous gain landscapes

    SciTech Connect

    Kartashov, Yaroslav V.; Vysloukh, Victor A.; Konotop, Vladimir V.

    2011-04-15

    We address one-dimensional soliton formation in a cubic nonlinear medium with two-photon absorption and transversally inhomogeneous gain landscape consisting of a single or several amplifying channels. Existence of the solitons requires certain threshold gain while the properties of solitons strongly depend on whether the number of the amplifying channels is odd or even. In the former case, an increase of the gain leads to symmetry breaking, which occurs through the pitchfork bifurcation, and to emergence of a single or several coexisting stable asymmetric modes. In the case of an even number of amplifying channels, we have found only asymmetric stable states.

  3. Fresnel reflection from a cavity with net roundtrip gain

    SciTech Connect

    Mansuripur, Tobias S.; Mansuripur, Masud

    2014-03-24

    A planewave incident on an active etalon with net roundtrip gain may be expected to diverge in field amplitude, yet applying the Fresnel formalism to Maxwell's equations admits a convergent solution. We describe this solution mathematically and provide additional insight by demonstrating the response of such a cavity to an incident beam of light. Cavities with net roundtrip gain have often been overlooked in the literature, and a clear understanding of their behavior yields insight to negative refraction in nonmagnetic media, a duality between loss and gain, amplified total internal reflection, and the negative-index lens.

  4. Macroscopic magnetic structures with balanced gain and loss

    NASA Astrophysics Data System (ADS)

    Lee, J. M.; Kottos, T.; Shapiro, B.

    2015-03-01

    We investigate magnetic nanostructures with balanced gain and loss and show that such configurations can result in a new type of dynamics for magnetization. Using the simplest possible setup consisting of two coupled ferromagnetic films, one with loss and another one with a balanced amount of gain, we demonstrate the existence of an exceptional point where both the eigenfrequencies and eigenvectors become degenerate. This point corresponds to a particular value of the gain and loss parameter α =αc . For α <αc the frequency spectrum is real, indicating stable dynamics, while for α >αc it is complex, signaling unstable dynamics which is, however, stabilized by nonlinearity.

  5. Nucleus accumbens response to gains in reputation for the self relative to gains for others predicts social media use.

    PubMed

    Meshi, Dar; Morawetz, Carmen; Heekeren, Hauke R

    2013-01-01

    Our reputation is important to us; we've experienced natural selection to care about our reputation. Recently, the neural processing of gains in reputation (positive social feedback concerning one's character) has been shown to occur in the human ventral striatum. It is still unclear, however, how individual differences in the processing of gains in reputation may lead to individual differences in real-world behavior. For example, in the real-world, one way that people currently maintain their reputation is by using social media websites, like Facebook. Furthermore, Facebook use consists of a social comparison component, where users observe others' behavior and can compare it to their own. Therefore, we hypothesized a relationship between the way the brain processes specifically self-relevant gains in reputation and one's degree of Facebook use. We recorded functional neuroimaging data while participants received gains in reputation, observed the gains in reputation of another person, or received monetary reward. We demonstrate that across participants, when responding to gains in reputation for the self, relative to observing gains for others, reward-related activity in the left nucleus accumbens predicts Facebook use. However, nucleus accumbens activity in response to monetary reward did not predict Facebook use. Finally, a control step-wise regression analysis showed that Facebook use primarily explains our results in the nucleus accumbens. Overall, our results demonstrate how individual sensitivity of the nucleus accumbens to the receipt of self-relevant social information leads to differences in real-world behavior.

  6. Nucleus accumbens response to gains in reputation for the self relative to gains for others predicts social media use

    PubMed Central

    Meshi, Dar; Morawetz, Carmen; Heekeren, Hauke R.

    2013-01-01

    Our reputation is important to us; we've experienced natural selection to care about our reputation. Recently, the neural processing of gains in reputation (positive social feedback concerning one's character) has been shown to occur in the human ventral striatum. It is still unclear, however, how individual differences in the processing of gains in reputation may lead to individual differences in real-world behavior. For example, in the real-world, one way that people currently maintain their reputation is by using social media websites, like Facebook. Furthermore, Facebook use consists of a social comparison component, where users observe others' behavior and can compare it to their own. Therefore, we hypothesized a relationship between the way the brain processes specifically self-relevant gains in reputation and one's degree of Facebook use. We recorded functional neuroimaging data while participants received gains in reputation, observed the gains in reputation of another person, or received monetary reward. We demonstrate that across participants, when responding to gains in reputation for the self, relative to observing gains for others, reward-related activity in the left nucleus accumbens predicts Facebook use. However, nucleus accumbens activity in response to monetary reward did not predict Facebook use. Finally, a control step-wise regression analysis showed that Facebook use primarily explains our results in the nucleus accumbens. Overall, our results demonstrate how individual sensitivity of the nucleus accumbens to the receipt of self-relevant social information leads to differences in real-world behavior. PMID:24009567

  7. Review of health and productivity gains from better IEQ

    SciTech Connect

    Fisk, William J.

    2000-08-01

    The available scientific data suggest that existing technologies and procedures can improve indoor environmental quality (IEQ) in a manner that significantly increases productivity and health. While there is considerable uncertainty in the estimates of the magnitudes of productivity gains that may be obtained, the projected gains are very large. For the U.S., the estimated potential annual savings and productivity gains are $6 to $14 billion from reduced respiratory disease, $2 to $4 billion from reduced allergies and asthma, $10 to $30 billion from reduced sick building syndrome symptoms, and $20 to $160 billion from direct improvements in worker performance that are unrelated to health. Productivity gains that are quantified and demonstrated could serve as a strong stimulus for energy efficiency measures that simultaneously improve the indoor environment.

  8. Menopause Weight Gain: Stop the Middle Age Spread

    MedlinePlus

    ... al. Diet and adipose tissue distributions: The multi-ethnic study of atherosclerosis. Nutrition, Metabolism & Cardiovascular Diseases. 2016;26:185. Greenberg JA, et al. Chocolate-candy consumption and three-year weight gain among postmenopausal U.S. ...

  9. Gas gain stabilisation in the ATLAS TRT detector

    NASA Astrophysics Data System (ADS)

    Mindur, B.; Åkesson, T. P. A.; Anghinolfi, F.; Antonov, A.; Arslan, O.; Baker, O. K.; Banas, E.; Bault, C.; Beddall, A. J.; Bendotti, J.; Benjamin, D. P.; Bertelsen, H.; Bingul, A.; Bocci, A.; Boldyrev, A. S.; Brock, I.; Capeáns Garrido, M.; Catinaccio, A.; Celebi, E.; Cetin, S. A.; Choi, K.; Dam, M.; Danielsson, H.; Davis, D.; Degeorge, C.; Derendarz, D.; Desch, K.; Di Girolamo, B.; Dittus, F.; Dixon, N.; Dressnandt, N.; Dubinin, F. A.; Evans, H.; Farthouat, P.; Fedin, O. L.; Froidevaux, D.; Gavrilenko, I. L.; Gay, C.; Gecse, Z.; Godlewski, J.; Grefe, C.; Gurbuz, S.; Hajduk, Z.; Hance, M.; Haney, B.; Hansen, J. B.; Hansen, P. H.; Hawkins, A. D.; Heim, S.; Holway, K.; Kantserov, V. A.; Katounine, S.; Kayumov, F.; Keener, P. T.; Kisielewski, B.; Klopov, N. V.; Konovalov, S. P.; Koperny, S.; Korotkova, N. A.; Kowalski, T. Z.; Kramarenko, V.; Krasnopevtsev, D.; Kruse, M.; Kudin, L. G.; Lichard, P.; Loginov, A.; Martinez, N. Lorenzo; Lucotte, A.; Luehring, F.; Lytken, E.; Maleev, V. P.; Maevskiy, A. S.; Manjarres Ramos, J.; Mashinistov, R. Y.; Meyer, C.; Mialkovski, V.; Mistry, K.; Mitsou, V. A.; Nadtochi, A. V.; Newcomer, F. M.; Novodvorski, E. G.; Ogren, H.; Oh, S. H.; Oleshko, S. B.; Olszowska, J.; Ostrowicz, W.; Palacino, G.; Patrichev, S.; Penwell, J.; Perez-Gomez, F.; Peshekhonov, V. D.; RØhne, O.; Reilly, M. B.; Rembser, C.; Ricken, O.; Romaniouk, A.; Rousseau, D.; Ryjov, V.; Sasmaz, U.; Schaepe, S.; Schegelsky, V. A.; Shmeleva, A. P.; Shulga, E.; Sivoklokov, S.; Smirnov, S.; Smirnov, Yu.; Smirnova, L. N.; Soldatov, E.; Sulin, V. V.; Tartarelli, G.; Taylor, W.; Thomson, E.; Tikhomirov, V. O.; Tipton, P.; Valls Ferrer, J. A.; Van Berg, R.; Vasquez, J.; Vasilyeva, L. F.; Vlazlo, O.; Weinert, B.; Williams, H. H.; Wong, V.; Zhukov, K. I.; Zieminska, D.

    2016-04-01

    The ATLAS (one of two general purpose detectors at the LHC) Transition Radiation Tracker (TRT) is the outermost of the three tracking subsystems of the ATLAS Inner Detector. It is a large straw-based detector and contains about 350,000 electronics channels. The performance of the TRT as tracking and particularly particle identification detector strongly depends on stability of the operation parameters with most important parameter being the gas gain which must be kept constant across the detector volume. The gas gain in the straws can vary significantly with atmospheric pressure, temperature, and gas mixture composition changes. This paper presents a concept of the gas gain stabilisation in the TRT and describes in detail the Gas Gain Stabilisation System (GGSS) integrated into the Detector Control System (DCS). Operation stability of the GGSS during Run-1 is demonstrated.

  10. Compulsive eating and weight gain related to dopamine agonist use.

    PubMed

    Nirenberg, Melissa J; Waters, Cheryl

    2006-04-01

    Dopamine agonists have been implicated in causing compulsive behaviors in patients with Parkinson's disease (PD). These have included gambling, hypersexuality, hobbyism, and other repetitive, purposeless behaviors ("punding"). In this report, we describe 7 patients in whom compulsive eating developed in the context of pramipexole use. All of the affected patients had significant, undesired weight gain; 4 had other comorbid compulsive behaviors. In the 5 patients who lowered the dose of pramipexole or discontinued dopamine agonist treatment, the behavior remitted and no further weight gain occurred. Physicians should be aware that compulsive eating resulting in significant weight gain may occur in PD as a side-effect of dopamine agonist medications such as pramipexole. Given the known risks of the associated weight gain and obesity, further investigation is warranted.

  11. Rehabilitation Gain: A New Criterion for an Old Concept

    ERIC Educational Resources Information Center

    Hawryluk, Alex

    1974-01-01

    A measure of rehabilitation success focusing on hours per week gainfully occupied, weekly earnings, work status, economic dependency, and psychological well being, was administered to 186 persons who had been receiving rehabilitative services 1 year earlier. (GW)

  12. Circadian Timing of Food Intake Contributes to Weight Gain

    PubMed Central

    Arble, Deanna M.; Bass, Joseph; Laposky, Aaron D.; Vitaterna, Martha H.; Turek, Fred W.

    2012-01-01

    Studies of body weight regulation have focused almost entirely on caloric intake and energy expenditure. However, a number of recent studies in animals linking energy regulation and the circadian clock at the molecular, physiological and behavioral levels raise the possibility that the timing of food intake itself may play a significant role in weight gain. The present study focused on the role of the circadian phase of food consumption in weight gain. We provide evidence that nocturnal mice fed a high fat diet only during the 12 hour light phase gain significantly more weight than mice fed only during the 12 hour dark phase. A better understanding of the role of the circadian system for weight gain could have important implications for developing new therapeutic strategies for combating the obesity epidemic facing the human population today. PMID:19730426

  13. Circadian timing of food intake contributes to weight gain.

    PubMed

    Arble, Deanna M; Bass, Joseph; Laposky, Aaron D; Vitaterna, Martha H; Turek, Fred W

    2009-11-01

    Studies of body weight regulation have focused almost entirely on caloric intake and energy expenditure. However, a number of recent studies in animals linking energy regulation and the circadian clock at the molecular, physiological, and behavioral levels raise the possibility that the timing of food intake itself may play a significant role in weight gain. The present study focused on the role of the circadian phase of food consumption in weight gain. We provide evidence that nocturnal mice fed a high-fat diet only during the 12-h light phase gain significantly more weight than mice fed only during the 12-h dark phase. A better understanding of the role of the circadian system for weight gain could have important implications for developing new therapeutic strategies for combating the obesity epidemic facing the human population today.

  14. Context-specific adaptation of saccade gain in parabolic flight

    NASA Technical Reports Server (NTRS)

    Shelhamer, Mark; Clendaniel, Richard A.; Roberts, Dale C.

    2002-01-01

    Previous studies established that vestibular reflexes can have two adapted states (e.g., gains) simultaneously, and that a context cue (e.g., vertical eye position) can switch between the two states. Our earlier work demonstrated this phenomenon of context-specific adaptation for saccadic eye movements: we asked for gain decrease in one context state and gain increase in another context state, and then determined if a change in the context state would invoke switching between the adapted states. Horizontal and vertical eye position and head orientation could serve, to varying degrees, as cues for switching between two different saccade gains. In the present study, we asked whether gravity magnitude could serve as a context cue: saccade adaptation was performed during parabolic flight, which provides alternating levels of gravitoinertial force (0 g and 1.8 g). Results were less robust than those from ground experiments, but established that different saccade magnitudes could be associated with different gravity levels.

  15. Perspective methods for the generation of COIL gain medium

    NASA Astrophysics Data System (ADS)

    Zagidullin, Marsel V.; Nikolaev, Valery D.; Svistun, Michael I.; Khvatov, Nikolay A.

    2007-04-01

    An ejector nozzle bank powered by centrifugal bubbling SOG is considered like highly efficient gain generating system for COIL. A high potential recovered pressure ~100 torr of the gain medium flow with a small signal gain higher than 1% cm -1 and low oxygen plenum pressure has been demonstrated. A centrifugal bubbling SOG is an efficient source of oxygen at high pressure with high depletion of the BHP in the single burn dawn. A high 0 II(1Δ) yield and chlorine utilization higher than 90% have been obtained at chlorine gas loading up to 6 mmole/s per 1 cm2 of the bubbler surface. The ejector COIL powered by centrifugal bubbling SOG demonstrated ~25% of chemical efficiency with specific power 6 kJ per 1 litre of the BHP in the single burn dawn. The combination of centrifugal bubble SOG with ejector nozzle bank can be considered as a promising gain medium flow generation system for COIL.

  16. Fluerics 42: Some commonly used laminar fluidic gain blocks

    NASA Astrophysics Data System (ADS)

    Drzewiecki, T. M.

    1982-09-01

    This report presents data and operating experience information on many commonly used laminar gain blocks from two to eight stages. In addition, as an aid to design, a short computer program is presented, suitable for use with a pocket programmable calculator. Outputs from this program are individual stage data including nominal supply pressures and flows and staged gain. Also available is the net gain and the bandwidth at 90 deg of phase shift. Several examples of this program are given to cover multiple-stage gain blocks. As an example of the utility of the program, a step-by-step tradeoff study is presented for the Massachusetts Institute of Technology fluidic servovalve, for which an attempt is made to maximize bandwidth and minimize leakage flow.

  17. Gain spectroscopy of a type-II VECSEL chip

    NASA Astrophysics Data System (ADS)

    Lammers, C.; Stein, M.; Berger, C.; Möller, C.; Fuchs, C.; Ruiz Perez, A.; Rahimi-Iman, A.; Hader, J.; Moloney, J. V.; Stolz, W.; Koch, S. W.; Koch, M.

    2016-12-01

    Using optical pump-white light probe spectroscopy, the gain dynamics is investigated for a vertical-external-cavity surface-emitting laser chip, which is based on a type-II heterostructure. The active region of the chip consists of a GaAs/(GaIn)As/Ga(AsSb)/(GaIn)As/GaAs multiple quantum well. For this structure, a fully microscopic theory predicts a modal room temperature gain at a wavelength of 1170 nm, which is confirmed by the experimental spectra. The results show a gain buildup on the type-II chip that is delayed relative to that of a type-I chip. This slower gain dynamics is attributed to a diminished cooling rate arising from the reduced electron-hole scattering.

  18. Recent Progress in High-Gain FEL Theory

    SciTech Connect

    Huang, Z.; /SLAC

    2005-09-30

    High-gain free electron lasers (FEL) are being developed as extremely bright x-ray sources of a next-generation radiation facility. In this paper, we review the basic theory and the recent progress in understanding the startup, the exponential growth and the saturation of the high-gain process, emphasizing the self-amplified spontaneous emission (SASE). We will also discuss how the FEL performance may be affected by various errors and wakefield effects in the undulator.

  19. Computer simulation of space station computer steered high gain antenna

    NASA Technical Reports Server (NTRS)

    Beach, S. W.

    1973-01-01

    The mathematical modeling and programming of a complete simulation program for a space station computer-steered high gain antenna are described. The program provides for reading input data cards, numerically integrating up to 50 first order differential equations, and monitoring up to 48 variables on printed output and on plots. The program system consists of a high gain antenna, an antenna gimbal control system, an on board computer, and the environment in which all are to operate.

  20. Fiber cavity ring down and gain amplification effect

    NASA Astrophysics Data System (ADS)

    Silva, Susana; Magalhães, Regina; Pérez-Herrera, Rosa Ana; Lopez-Amo, Manuel; Marques, M. B.; Frazão, O.

    2016-12-01

    The effect of an erbium-doped fiber amplifier (EDFA) placed inside the fiber ring of a cavity ring down (CRD) configuration is studied. The limitations and advantages of this configuration are discussed, and the study of the ring-down time as a function of the current applied and gain to the EDFA is also presented. In this case, the power fluctuations in the output signal are strongly dependent on the cavity ring-down time with the EDFA gain.

  1. Identifying the mechanisms of intron gain: progress and trends

    PubMed Central

    2012-01-01

    Abstract Continued improvements in Next-Generation DNA/RNA sequencing coupled with advances in gene annotation have provided researchers access to a plethora of annotated genomes. Subsequent analyses of orthologous gene structures have identified numerous intron gain and loss events that have occurred both recently and in the very distant past. This research has afforded exceptional insight into the temporal and lineage-specific rates of intron gain and loss among various species throughout evolution. Numerous studies have also attempted to identify the molecular mechanisms of intron gain and loss. However, even after considerable effort, very little is known about these processes. In particular, the mechanism(s) of intron gain have proven exceptionally enigmatic and remain topics of considerable debate. Currently, there exists no definitive consensus as to what mechanism(s) may generate introns. Because many introns are known to affect gene expression, it is necessary to understand the molecular process(es) by which introns may be gained. Here we review the seven most commonly purported mechanisms of intron gain and, when possible, summarize molecular evidence for or against the occurrence of each of these mechanisms. Furthermore, we catalogue indirect evidence that supports the occurrence of each mechanism. Finally, because these proposed mechanisms fail to explain the mechanistic origin of many recently gained introns, we also look at trends that may aid researchers in identifying other potential mechanism(s) of intron gain. Reviewers This article was reviewed by Eugene Koonin, Scott Roy (nominated by W. Ford Doolittle), and John Logsdon. PMID:22963364

  2. Regional Vicarious Gain Adjustment for Coastal VIIRS Products

    DTIC Science & Technology

    2014-01-01

    varying complexity of CDOM, sedimentary, and chlorophyll components Time series data .sets were used to develop a vicarious gain adjustment (VGA) at...of CDOM, sedimentary, and chlorophyll components. Time series data sets were used to develop a vicarious gain adjustment (VGA) at this site, which...reflectance) to geophysical data products ( chlorophyll a and others). The quality of calibration and subsequent validation activities and conversion

  3. High gain amplifiers: Power oscillations and harmonic generation

    SciTech Connect

    Dattoli, G.; Ottaviani, P. L.; Pagnutti, S.

    2007-08-01

    We discuss the power oscillations in saturated high gain free electron laser amplifiers and show that the relevant period can be written in terms of the gain length. We use simple arguments following from the solution of the pendulum equation in terms of Jacobi elliptic functions. Nontrivial effects due to nonlinear harmonic generation and inhomogeneous broadening are discussed too, as well as the saturated dynamics of short pulses.

  4. Gain Coupling of Class A Semiconductor Lasers (Postprint)

    DTIC Science & Technology

    2010-09-01

    AFRL-RY-WP-TP-2010-1250 GAIN COUPLING OF CLASS A SEMICONDUCTOR LASERS (POSTPRINT) Chris Hessenius, Mahmoud Fallahi, and Jerome Moloney...PROGRAM ELEMENT NUMBER 62204F 6. AUTHOR(S) Chris Hessenius, Mahmoud Fallahi, and Jerome Moloney (University of Arizona) Nathan Terry and Robert...98) Prescribed by ANSI Std. Z39-18 Gain coupling of class A semiconductor lasers Chris Hessenius,1,* Nathan Terry,2 Mahmoud Fallahi,1 Jerome

  5. Gain compression effect on the modulation dynamics of an optically injection-locked semiconductor laser using gain lever

    NASA Astrophysics Data System (ADS)

    Sarraute, J.-M.; Schires, K.; LaRochelle, S.; Grillot, F.

    2016-03-01

    The modulation response of an optically-injected gain lever semiconductor laser is studied and calculations show that a gain-lever laser operating under medium to strong optical injection provides a unique and robust configuration for ultra large bandwidth enhancement. Modulation bandwidths above nine times the relaxation oscillation frequency of the free-running laser can be reached using injection-locking conditions that are reasonable for practical applications. The impact of the gain compression on the modulation dynamic is discussed for the first time. This work is of prime importance for the development of directly-modulated broadband optical sources for high-speed operation at 40 Gbps and beyond.

  6. Dieting: proxy or cause of future weight gain?

    PubMed

    Lowe, M R

    2015-02-01

    The relationship between dieting and body mass has a long and controversial history. This paper aims to help resolve this issue by making two key distinctions. The first is between dieting as a cause of weight gain/regain and as a proxy risk factor for identifying non-obese individuals prone to weight gain for reasons other than dieting. The second is between the body mass that is attained following one or more weight loss/regain cycles and the body mass that might have been reached had dieting never been undertaken. Evidence is reviewed on the relation between recent diet-induced weight loss and sustained weight loss (weight suppression), on the one hand, and weight regain, on the other hand. Furthermore, the reason that a history of dieting in non-obese individuals reflects a susceptibility to future weight gain is explained. It is concluded that (i) diet-induced weight loss hastens weight regain but a history of weight loss diets does not cause weight gain beyond that which would occur in the absence of dieting, and (ii) weight loss dieting in non-obese individuals does not cause future weight gain but is simply a proxy risk factor reflecting a personal vulnerability to weight gain and living in an obesogenic environment.

  7. Modeling surface plasmon-polariton gain in planar metallic structures.

    PubMed

    De Leon, Israel; Berini, Pierre

    2009-10-26

    Amplification of the single-interface and long-range surface plasmon-polariton modes is studied in planar metallic structures incorporating gain media formed by Rhodamine 6G dye molecules in solution. We employ a theoretical model that accounts for the nonuniformity of the gain medium close to the metal surface due to position-dependent dipole lifetime and pump irradiance. The results of this model are used as a baseline for a comparative study against two simplified models: one neglects the position-dependent dipole lifetime while the other assumes a uniform gain medium. The discrepancies between the models are explained in terms of the mode overlap with the gain distribution near the metal. For the cases under analysis, the simplified models estimate the required pump irradiance with deviation factors that vary from 1.45 at the lossless conditions to 8 for gains near saturation. The relevance of describing properly the amount o gain interacting with the SPP mode and the role played by the dipole quantum efficiency are discussed.

  8. Weight gain prevention and smoking cessation: cautionary findings.

    PubMed Central

    Hall, S M; Tunstall, C D; Vila, K L; Duffy, J

    1992-01-01

    OBJECTIVES. Weight gain is a consistent sequela of smoking cessation. A successful intervention might attract smokers who fear weight gain. If the gain causes smoking relapse, such an intervention might reduce smoking relapse risk. METHODS. Using a sample of 158 smokers who completed a 2-week smoking treatment program, we compared an innovative weight gain prevention intervention with both a nonspecific treatment and standard treatment. Subjects were assessed on weight and smoking behavior and followed for 1 year. RESULTS. A disturbing, unexpected finding was that subjects in both the innovative and nonspecific conditions had a higher risk of smoking relapse than did standard treatment subjects. Some differences were observed between abstinent and smoking subjects in weight gain by treatment condition. CONCLUSIONS. Both active interventions may have been so complicated that they detracted from nonsmoking. Also, caloric restriction may increase the reinforcing value of nicotine, a psychoactive drug, thereby increasing smoking relapse risk. The magnitude of weight gain after smoking cessation may not merit interventions that increase smoking risk. Perhaps attitudinal modifications are the most appropriate. PMID:1585959

  9. Intestinal Microbiota and Weight-Gain in Preterm Neonates

    PubMed Central

    Arboleya, Silvia; Martinez-Camblor, Pablo; Solís, Gonzalo; Suárez, Marta; Fernández, Nuria; de los Reyes-Gavilán, Clara G.; Gueimonde, Miguel

    2017-01-01

    The involvement of the gut microbiota on weight-gain and its relationship with childhood undernutrition and growth has been reported. Thus, the gut microbiota constitutes a potential therapeutic target for preventing growth impairment. However, our knowledge in this area is limited. In this study we aimed at evaluating the relationship among early microbiota, growth, and development in preterm infants. To this end we assessed the levels of specific microorganisms by qPCR, and those of short chain fatty acids by mean of gas-chromatography, in feces from 63 preterm newborns and determined their weight-gain during the first months. The statistical analyses performed indicate an influence of the intestinal microbiota in weight-gain, with the levels of some microorganisms showing a significant association with the weight-gain of the infant. The levels of specific microbial groups during the first days of life were found to affect weight gain by the age of 1 month. Moreover, clustering of the infants on the basis of the microbiota composition at 1 month of age rendered groups which showed differences in weight z-scores. Our results suggest an association between the gut microbiota composition and weight-gain in preterm infants at early life and point out potential microbial targets for favoring growth and maturation in these infants. PMID:28228752

  10. Streamflow gain and loss of selected streams in northern Arkansas

    USGS Publications Warehouse

    Freiwald, David A.

    1987-01-01

    This map shows streamflow gain and loss measurements (seepage runs) on the Crooked, Osage, and Spavinaw Creeks, and Illinois, Kings, Mulberry, Spring, and Strawberry Rivers during the low-flow conditions from September 1982 to October 1984. Data indicated that streamflow gains and losses resulted from differences in lithology of the predominately carbonate rocks and from the presence of faults. The Kings and Strawberry Rivers and Osage Creek were gaining streams throughout their length, however wastewater discharges precluded an accurate determination on Osage Creek. Crooked and Spavinaw Creeks and the Illinois, Spring, and Mulberry Rivers generally were gaining streams throughout most of their lengths although short losing reaches were identified. The largest gains in streamflow generally occurred were Mississippian formation predominated near the streams. Faults that intersected the stream channels primarily were responsible for streamflow losses. The specific conductance of water increased in the stream reaches that had the most significant streamflow gains. The specific conductance of water in tributaries was generally higher than that in larger streams. (Author 's abstract)

  11. Intestinal Microbiota and Weight-Gain in Preterm Neonates.

    PubMed

    Arboleya, Silvia; Martinez-Camblor, Pablo; Solís, Gonzalo; Suárez, Marta; Fernández, Nuria; de Los Reyes-Gavilán, Clara G; Gueimonde, Miguel

    2017-01-01

    The involvement of the gut microbiota on weight-gain and its relationship with childhood undernutrition and growth has been reported. Thus, the gut microbiota constitutes a potential therapeutic target for preventing growth impairment. However, our knowledge in this area is limited. In this study we aimed at evaluating the relationship among early microbiota, growth, and development in preterm infants. To this end we assessed the levels of specific microorganisms by qPCR, and those of short chain fatty acids by mean of gas-chromatography, in feces from 63 preterm newborns and determined their weight-gain during the first months. The statistical analyses performed indicate an influence of the intestinal microbiota in weight-gain, with the levels of some microorganisms showing a significant association with the weight-gain of the infant. The levels of specific microbial groups during the first days of life were found to affect weight gain by the age of 1 month. Moreover, clustering of the infants on the basis of the microbiota composition at 1 month of age rendered groups which showed differences in weight z-scores. Our results suggest an association between the gut microbiota composition and weight-gain in preterm infants at early life and point out potential microbial targets for favoring growth and maturation in these infants.

  12. Weight gain in smokers after quitting cigarettes: meta-analysis

    PubMed Central

    Farley, Amanda; Lycett, Deborah; Lahmek, Pierre; Aveyard, Paul

    2012-01-01

    Objective To describe weight gain and its variation in smokers who achieve prolonged abstinence for up to 12 months and who quit without treatment or use drugs to assist cessation. Design Meta-analysis. Data sources We searched the Central Register of Controlled Trials (CENTRAL) and trials listed in Cochrane reviews of smoking cessation interventions (nicotine replacement therapy, nicotinic partial agonists, antidepressants, and exercise) for randomised trials of first line treatments (nicotine replacement therapy, bupropion, and varenicline) and exercise that reported weight change. We also searched CENTRAL for trials of interventions for weight gain after cessation. Review methods Trials were included if they recorded weight change from baseline to follow-up in abstinent smokers. We used a random effects inverse variance model to calculate the mean and 95% confidence intervals and the mean of the standard deviation for weight change from baseline to one, two, three, six, and 12 months after quitting. We explored subgroup differences using random effects meta-regression. Results 62 studies were included. In untreated quitters, mean weight gain was 1.12 kg (95% confidence interval 0.76 to 1.47), 2.26 kg (1.98 to 2.54), 2.85 kg (2.42 to 3.28), 4.23 kg (3.69 to 4.77), and 4.67 kg (3.96 to 5.38) at one, two, three, six, and 12 months after quitting, respectively. Using the means and weighted standard deviations, we calculated that at 12 months after cessation, 16%, 37%, 34%, and 13% of untreated quitters lost weight, and gained less than 5 kg, gained 5-10 kg, and gained more than 10 kg, respectively. Estimates of weight gain were similar for people using different pharmacotherapies to support cessation. Estimates were also similar between people especially concerned about weight gain and those not concerned. Conclusion Smoking cessation is associated with a mean increase of 4-5 kg in body weight after 12 months of abstinence, and most weight gain occurs within three

  13. Exercise during pregnancy and its association with gestational weight gain.

    PubMed

    Harris, Shericka T; Liu, Jihong; Wilcox, Sara; Moran, Robert; Gallagher, Alexa

    2015-03-01

    We examined the association between exercise during pregnancy and meeting gestational weight gain recommendations. Data came from the 2009 South Carolina Pregnancy Risk Assessment Monitoring System (n = 856). Women reported their participation in exercise/sports activities before and during pregnancy, including the number of months and types of exercise. We developed an exercise index (EI), the product of the number of months spent in exercise and average metabolic equivalents for specific exercise. The 2009 Institute of Medicine's guideline was used to categorize gestational weight gain into three classes: inadequate, adequate, and excessive. Multinomial logistic regression models were used to adjust for confounders. Over 46 % of women exceeded the recommended weight gain during pregnancy. Nearly one third (31.9 %) of women reported exercising ≥3 times a week at any time during pregnancy. Compared to women who did not report this level of exercise during pregnancy, exercising women were more likely to meet gestational weight gain recommendations (32.7 vs. 18.7 %) and had a lower odds of excessive gestational weight gain [adjusted odds ratio (AOR) 0.43, 95 % confidence interval 0.24-0.78]. Women with an EI above the median value of those women who exercised or women who exercised ≥3 times a week for 6-9 months during pregnancy had lower odds of excessive gestational weight gain (AOR for EI 0.20, 0.08-0.49; AOR for months 0.26, 0.12-0.56, respectively). Our findings support the need to promote or increase exercise during pregnancy to reduce the high proportion of women who are gaining excessive weight.

  14. Global Patterns of Protein Domain Gain and Loss in Superkingdoms

    PubMed Central

    Nasir, Arshan; Kim, Kyung Mo; Caetano-Anollés, Gustavo

    2014-01-01

    Domains are modules within proteins that can fold and function independently and are evolutionarily conserved. Here we compared the usage and distribution of protein domain families in the free-living proteomes of Archaea, Bacteria and Eukarya and reconstructed species phylogenies while tracing the history of domain emergence and loss in proteomes. We show that both gains and losses of domains occurred frequently during proteome evolution. The rate of domain discovery increased approximately linearly in evolutionary time. Remarkably, gains generally outnumbered losses and the gain-to-loss ratios were much higher in akaryotes compared to eukaryotes. Functional annotations of domain families revealed that both Archaea and Bacteria gained and lost metabolic capabilities during the course of evolution while Eukarya acquired a number of diverse molecular functions including those involved in extracellular processes, immunological mechanisms, and cell regulation. Results also highlighted significant contemporary sharing of informational enzymes between Archaea and Eukarya and metabolic enzymes between Bacteria and Eukarya. Finally, the analysis provided useful insights into the evolution of species. The archaeal superkingdom appeared first in evolution by gradual loss of ancestral domains, bacterial lineages were the first to gain superkingdom-specific domains, and eukaryotes (likely) originated when an expanding proto-eukaryotic stem lineage gained organelles through endosymbiosis of already diversified bacterial lineages. The evolutionary dynamics of domain families in proteomes and the increasing number of domain gains is predicted to redefine the persistence strategies of organisms in superkingdoms, influence the make up of molecular functions, and enhance organismal complexity by the generation of new domain architectures. This dynamics highlights ongoing secondary evolutionary adaptations in akaryotic microbes, especially Archaea. PMID:24499935

  15. Patterns of intron gain and conservation in eukaryotic genes

    PubMed Central

    Carmel, Liran; Rogozin, Igor B; Wolf, Yuri I; Koonin, Eugene V

    2007-01-01

    Background: The presence of introns in protein-coding genes is a universal feature of eukaryotic genome organization, and the genes of multicellular eukaryotes, typically, contain multiple introns, a substantial fraction of which share position in distant taxa, such as plants and animals. Depending on the methods and data sets used, researchers have reached opposite conclusions on the causes of the high fraction of shared introns in orthologous genes from distant eukaryotes. Some studies conclude that shared intron positions reflect, almost entirely, a remarkable evolutionary conservation, whereas others attribute it to parallel gain of introns. To resolve these contradictions, it is crucial to analyze the evolution of introns by using a model that minimally relies on arbitrary assumptions. Results: We developed a probabilistic model of evolution that allows for variability of intron gain and loss rates over branches of the phylogenetic tree, individual genes, and individual sites. Applying this model to an extended set of conserved eukaryotic genes, we find that parallel gain, on average, accounts for only ~8% of the shared intron positions. However, the distribution of parallel gains over the phylogenetic tree of eukaryotes is highly non-uniform. There are, practically, no parallel gains in closely related lineages, whereas for distant lineages, such as animals and plants, parallel gains appear to contribute up to 20% of the shared intron positions. In accord with these findings, we estimated that ancestral introns have a high probability to be retained in extant genomes, and conversely, that a substantial fraction of extant introns have retained their positions since the early stages of eukaryotic evolution. In addition, the density of sites that are available for intron insertion is estimated to be, approximately, one in seven basepairs. Conclusion: We obtained robust estimates of the contribution of parallel gain to the observed sharing of intron positions

  16. Dieting and restrained eating as prospective predictors of weight gain.

    PubMed

    Lowe, Michael R; Doshi, Sapna D; Katterman, Shawn N; Feig, Emily H

    2013-09-02

    Research in normal weight individuals paradoxically suggests that measures of attempted eating restriction might represent robust predictors of weight gain. This review examined the extent to which measures of dieting (e.g., self-reported weight loss dieting in the past year) and dietary restraint (e.g., the Cognitive Restraint scale from the Three-Factor Eating Questionnaire) have prospectively predicted weight change. We located and reviewed 25 prospective studies containing 40 relevant comparisons. Studies were limited to those in which participants were non-obese (with a mean BMI between 18.5 and 30) and averaged at least 12 years old. Neither measure predicted future weight loss. Fifteen of the 20 comparisons (75%) that examined measures of dieting significantly predicted future weight gain whereas only 1 of 20 (5%) that examined restrained eating measures did so. Two plausible explanations for these findings are that: (1) dieters and restrained eaters do not differ in terms of an underlying proneness toward weight gain, but restrained eating represents a more effective means of preventing it; and (2) normal weight individuals who diet do so because they are resisting a powerful predisposition toward weight gain which dieting ultimately fails to prevent. Recent dieting in non-obese individuals may be a valuable proxy of susceptibility to weight gain. This easily assessed characteristic could identify individuals for whom obesity prevention interventions would be particularly appropriate.

  17. Direct and Indirect Approaches to Increasing Conceptual Survey Gains

    NASA Astrophysics Data System (ADS)

    Kohl, Patrick B.; Pearl, Charles; Kuo, H. Vincent

    2010-10-01

    Conceptual surveys like the FCI and CSEM are common, and course reforms often have the goal of improving student gains on these surveys. There exist various approaches to improving said gains, and there is occasionally concern that such methods "teach to the test" excessively. To our knowledge, however, there has been little direct experimentation on whether teaching to the test, even intentionally, has the expected result. In this paper, we report on a simple two-semester experiment involving ˜900 students where we tried two different approaches to improving CSEM gains in an introductory E&M class. In the first trial, we gave students many of the questions from the CSEM as Peer Instruction-style clicker questions in lecture. In the second, we redeveloped parts of our Studio physics curriculum to target CSEM concepts without replicating CSEM questions. Comparing the CSEM gains in the experimental sections to the previous year's sections, we find that the first trial resulted in significant (˜0.20) shifts in normalized gains on the relevant questions, while the second trial resulted in minimal or no shifts.

  18. Obesity and diabetes genetic variants associated with gestational weight gain

    PubMed Central

    Stuebe, Alison M.; Lyon, Helen; Herring, Amy; Ghosh, Joyee; Wise, Alison; North, Kari E.; Siega-Riz, Anna Maria

    2011-01-01

    Objective To determine whether genetic variants associated with diabetes and obesity predict gestational weight gain. Study Design 960 participants in the Pregnancy, Infection and Nutrition cohorts were genotyped for 27 single-nucleotide polymorphisms (SNPs) associated with diabetes and obesity. Results Among white and black women (n=960), KCNQ1 risk allele carriage was directly associated with weight gain (p < 0.01). In Bayesian hierarchical models among white women (N=628), we found posterior odds ratios > 3 for inclusion of TCF2 and THADA SNPs in our models. Among black women (n=332), we found associations between risk allele carriage and weight gain for the THADA and INSIG2 SNPs. In Bayesian variable selection models, we found an interaction between the TSPAN8 risk allele and pre-gravid obesity, with lower weight gain among obese risk allele carriers. Conclusion We found evidence that diabetes and obesity risk alleles interact with maternal pre-gravid BMI to predict gestational weight gain. PMID:20816152

  19. Weight gain in freshman college students and perceived health

    PubMed Central

    de Vos, Paul; Hanck, Christoph; Neisingh, Marjolein; Prak, Dennis; Groen, Henk; Faas, Marijke M.

    2015-01-01

    Background We determined body weight increase in first year Dutch college students. We had the objective to determine whether the awareness of the unhealthy lifestyle raised concerns and willingness to change habits. Methods Body weight, heartbeat, BMI, body fat percentages, and blood pressure values were collected from 1095 students. Comprehensive statistical analysis was performed on the data. Results The students had a mean weight gain of 1.1 kg and an average BMI gain of 0.35. Members of a student corps gained significantly more weight (1.6 ± 3.1 kg) than non-members (1.0 ± 2.5 kg), while students who are living independently gained an average of 0.5 kg more than students living with their parents (p < 0.05). Approximately 40% of the students changed their eating patterns and 30.7% of the students consumed more alcohol. Conclusions Students experienced hindrance in physical exercise and mental well-being. Students with a high BMI without irregular eating habits were willing to change their lifestyle. However, students who had irregular lifestyles exhibited the lowest willingness to change their eating behaviors and to lose weight. Our study provides insight into means by which adolescents at high risk for weight gain can be approached to improve experienced quality of life. PMID:26844076

  20. ZnO nanowire UV photodetectors with high internal gain.

    PubMed

    Soci, C; Zhang, A; Xiang, B; Dayeh, S A; Aplin, D P R; Park, J; Bao, X Y; Lo, Y H; Wang, D

    2007-04-01

    ZnO nanowire (NW) visible-blind UV photodetectors with internal photoconductive gain as high as G approximately 108 have been fabricated and characterized. The photoconduction mechanism in these devices has been elucidated by means of time-resolved measurements spanning a wide temporal domain, from 10-9 to 102 s, revealing the coexistence of fast (tau approximately 20 ns) and slow (tau approximately 10 s) components of the carrier relaxation dynamics. The extremely high photoconductive gain is attributed to the presence of oxygen-related hole-trap states at the NW surface, which prevents charge-carrier recombination and prolongs the photocarrier lifetime, as evidenced by the sensitivity of the photocurrrent to ambient conditions. Surprisingly, this mechanism appears to be effective even at the shortest time scale investigated of t < 1 ns. Despite the slow relaxation time, the extremely high internal gain of ZnO NW photodetectors results in gain-bandwidth products (GB) higher than approximately 10 GHz. The high gain and low power consumption of NW photodetectors promise a new generation of phototransistors for applications such as sensing, imaging, and intrachip optical interconnects.

  1. Food groups and weight gain in Japanese men.

    PubMed

    Ibe, Y; Takahashi, Y; Sone, H

    2014-06-01

    Identifying subjects at high risk of weight gain according to consumption of food groups is important for individualizing nutritional education, but prospective studies of this issue have been few. We determined whether intake of specific food groups could predict future weight gain. We evaluated data from health checkups on 1236 Japanese men aged 28 to 87 years in 2005 and 2006. Dietary intake was assessed by a 24-h dietary recall at baseline. Weight change was measured after 1 year. Weight increased in 44.7% (n = 553) of participants. Multivariate regression analysis involving many food groups showed a significant association between sugar intake and weight gain after adjustment for age, body mass index (BMI), total energy intake, alcohol, smoking and regular physical exercise (β = 0.22, P = 0.04). The effect of intake of 'fats and oils' was significant when adjusted for age and BMI, however, it became insignificant after adjustment for age, BMI and total energy intake. Intake of sugar, which was evaluated as a food group, was predictive of subsequent weight gain among Japanese men, even after adjustment for many confounders. This corroborates the evidence so far concerning the links between sugar intake and weight gain. Further long-term research is required to give robust recommendation to the public.

  2. Hitchhiking selection is driving intron gain in a pathogenic fungus.

    PubMed

    Brunner, Patrick C; Torriani, Stefano F F; Croll, Daniel; Stukenbrock, Eva H; McDonald, Bruce A

    2014-07-01

    The variability of intron density among eukaryotes is puzzling and still debated. Most previous studies have been limited because of the near absence of intron presence-absence polymorphism (IPAP) within species or because comparisons could be made only between distantly related species. We conducted population genetic analyses on eight loci showing IPAP to investigate the effect of natural selection on intron dynamics in a global collection of the panmictic fungal plant pathogen Zymoseptoria tritici and its very close relatives. Five of these loci likely represent recent intron gains because their absence is fixed among the closest relatives of Z. tritici, and three likely represent recent intron losses because their presence is fixed among the close relatives. We analyzed signatures of selection by comparing allele frequencies, nucleotide diversities, and rates of recombination and found compelling evidence that at least two out of the five intron-gain loci, a SWIM zinc-finger gene and a sugar transporter, are under directional selection favoring alleles that gained the intron. Our results suggest that the intron-present alleles of these loci are sweeping to fixation, providing a genetic hitchhiking mechanism to explain rapid intron gain in Z. tritici. The overall findings are consistent with the hypothesis that intron gains are more likely to be driven by selection while intron losses are more likely to be due to neutral processes such as genetic drift.

  3. Neural Net Gains Estimation Based on an Equivalent Model

    PubMed Central

    Aguilar Cruz, Karen Alicia; Medel Juárez, José de Jesús; Fernández Muñoz, José Luis; Esmeralda Vigueras Velázquez, Midory

    2016-01-01

    A model of an Equivalent Artificial Neural Net (EANN) describes the gains set, viewed as parameters in a layer, and this consideration is a reproducible process, applicable to a neuron in a neural net (NN). The EANN helps to estimate the NN gains or parameters, so we propose two methods to determine them. The first considers a fuzzy inference combined with the traditional Kalman filter, obtaining the equivalent model and estimating in a fuzzy sense the gains matrix A and the proper gain K into the traditional filter identification. The second develops a direct estimation in state space, describing an EANN using the expected value and the recursive description of the gains estimation. Finally, a comparison of both descriptions is performed; highlighting the analytical method describes the neural net coefficients in a direct form, whereas the other technique requires selecting into the Knowledge Base (KB) the factors based on the functional error and the reference signal built with the past information of the system. PMID:27366146

  4. Neural Net Gains Estimation Based on an Equivalent Model.

    PubMed

    Aguilar Cruz, Karen Alicia; Medel Juárez, José de Jesús; Fernández Muñoz, José Luis; Esmeralda Vigueras Velázquez, Midory

    2016-01-01

    A model of an Equivalent Artificial Neural Net (EANN) describes the gains set, viewed as parameters in a layer, and this consideration is a reproducible process, applicable to a neuron in a neural net (NN). The EANN helps to estimate the NN gains or parameters, so we propose two methods to determine them. The first considers a fuzzy inference combined with the traditional Kalman filter, obtaining the equivalent model and estimating in a fuzzy sense the gains matrix A and the proper gain K into the traditional filter identification. The second develops a direct estimation in state space, describing an EANN using the expected value and the recursive description of the gains estimation. Finally, a comparison of both descriptions is performed; highlighting the analytical method describes the neural net coefficients in a direct form, whereas the other technique requires selecting into the Knowledge Base (KB) the factors based on the functional error and the reference signal built with the past information of the system.

  5. Scientific reasoning and FCI gains for a Community College population

    NASA Astrophysics Data System (ADS)

    Diff, Karim; Tache, N.

    2007-05-01

    In a recent paper (AJP, 73:1172, (2005)), Coletta and Phillips have found positive correlations between pre-instruction scores and normalized gains on the FCI, as well as between scores on the Lawson classroom test of scientific reasoning and normalized FCI gains. This poster presents results from a similar study conducted with a community college population. Students from seven different physics classes taught by three different instructors were tested during the fall semester. Students were further grouped in three different levels of physics ( applied physics, algebra-based physics, calculus-based physics). In addition to analyzing the correlations between the FCI gains and the scores on the Lawson test, we discuss the interactive engagement techniques used by the instructors and the most significant differences between the performances of the three groups of students.

  6. Note: Non-gain microchannel plate gated framing camera

    SciTech Connect

    Cai Houzhi; Peng Xiang; Liu Jinyuan; Niu Lihong; Peng Wenda; Niu Hanben; Long Jinghua

    2011-05-15

    An x-ray framing camera using a non-gain microchannel plate (MCP) is reported in this article. The advantage of the non-gain MCP is the less transit time spread. The non-gain MCP gated framing camera has four microstrip line cathodes with 6 mm in width. The time domain reflectometry curves of the four microstrip lines are measured, which show that the characteristic impedance of each microstrip line is about 17 {Omega}. While the photocathode is driven by the gating electrical pulse with width of 125 ps and amplitude of -1.48 kV with -400 V bias, the measured exposure time of this camera is about 72 ps.

  7. Note: Non-gain microchannel plate gated framing camera.

    PubMed

    Cai, Houzhi; Liu, Jinyuan; Peng, Xiang; Niu, Lihong; Peng, Wenda; Niu, Hanben; Long, Jinghua

    2011-05-01

    An x-ray framing camera using a non-gain microchannel plate (MCP) is reported in this article. The advantage of the non-gain MCP is the less transit time spread. The non-gain MCP gated framing camera has four microstrip line cathodes with 6 mm in width. The time domain reflectometry curves of the four microstrip lines are measured, which show that the characteristic impedance of each microstrip line is about 17 Ω. While the photocathode is driven by the gating electrical pulse with width of 125 ps and amplitude of -1.48 kV with -400 V bias, the measured exposure time of this camera is about 72 ps.

  8. Gains in fluid ability performance and their relationship to cortisol.

    PubMed

    Kelly, K S; Hayslip, B

    2000-01-01

    The present analyses examined the relationship between cortisol and performance gains in crystallized (Gc) and fluid (Gf) ability, as well as the relationship to measures of everyday cognitive functioning in a sample of 73 older adults. The analyses were part of a larger study examining the impact of anxiety-reduction training on everyday tasks. Cortisol was assessed via urine sampling. Results indicated that there was a significant negative correlation between cortisol and performance gains for Gf, replicating earlier findings reported by our laboratory. These findings also extend the relationship to cortisol measured in urine; previous analyses were conducted using serum-based cortisol. Cortisol was also significantly related to performance gains in some measures of everyday cognitive functioning.

  9. Use of the variable gain settings on SPOT

    USGS Publications Warehouse

    Chavez, P.S.

    1989-01-01

    Often the brightness or digital number (DN) range of satellite image data is less than optimal and uses only a portion of the available values (0 to 255) because the range of reflectance values is small. Most imaging systems have been designed with only two gain settings, normal and high. The SPOT High Resolution Visible (HRV) imaging system has the capability to collect image data using one of eight different gain settings. With the proper procedure this allows the brightness or reflectance resolution, which is directly related to the range of DN values recorded, to be optimized for any given site as compared to using a single set of gain settings everywhere. -from Author

  10. Characteristics of current filamentation in high gain photoconductive semiconductor switching

    SciTech Connect

    Zutavern, F J; Loubriel, G M; O'Malley, M W; Helgeson, W D; McLaughlin, D L; Denison, G J

    1992-01-01

    Characteristics of current filamentation are reported for high gain photoconductive semiconductor switches (PCSS). Infrared photoluminescence is used to monitor carrier recombination radiation during fast initiation of high gain switching in large (1.5 cm gap) lateral GaAs PCSS. Spatial modulation of the optical trigger, a 200--300 ps pulse width laser, is examined. Effects on the location and number of current filaments, rise time, and delay to high gain switching, minimum trigger energy, and degradation of switch contacts are presented. Implications of these measurements for the theoretical understanding and practical development of these switches are discussed. Efforts to increase current density and reduce switch size and optical trigger energy requirements are described. Results from contact development and device lifetime testing are presented and the impact of these results on practical device applications is discussed.

  11. Information Gain Based Dimensionality Selection for Classifying Text Documents

    SciTech Connect

    Dumidu Wijayasekara; Milos Manic; Miles McQueen

    2013-06-01

    Selecting the optimal dimensions for various knowledge extraction applications is an essential component of data mining. Dimensionality selection techniques are utilized in classification applications to increase the classification accuracy and reduce the computational complexity. In text classification, where the dimensionality of the dataset is extremely high, dimensionality selection is even more important. This paper presents a novel, genetic algorithm based methodology, for dimensionality selection in text mining applications that utilizes information gain. The presented methodology uses information gain of each dimension to change the mutation probability of chromosomes dynamically. Since the information gain is calculated a priori, the computational complexity is not affected. The presented method was tested on a specific text classification problem and compared with conventional genetic algorithm based dimensionality selection. The results show an improvement of 3% in the true positives and 1.6% in the true negatives over conventional dimensionality selection methods.

  12. Gain spectrum in gated x-ray MCPs

    SciTech Connect

    Kyrala, George A; Oertel, John A; Archuleta, Thomas N; Holder, Joe

    2009-01-01

    The gain spectrum in a gated multichannel intensifier output depends on the gain and spatial averaging. The spectrum affects the minimum signal that can be detected as well as the signal to noise in the detected images. We will present data on the gain-spectrum for the GXD detector, a gated x-ray detector to be used at the National Ignition Facility. The data was recorded on a cooled CCD detector, with an x-ray gating time of approximately 75 ps, selected from a range of 0.2 and 1 ns electrical pulse width determined by pulse forming modules were also used. The detector was characterized at the TRIDENT laser facility, using a 2.4 ns long x-ray at 4.75 keV. The x-rays were generated by the interaction of the focused Trident laser beam with a Titanium target.

  13. Optofluidic lasers with a single molecular layer of gain.

    PubMed

    Chen, Qiushu; Ritt, Michael; Sivaramakrishnan, Sivaraj; Sun, Yuze; Fan, Xudong

    2014-12-21

    We achieve optofluidic lasers with a single molecular layer of gain, in which green fluorescent protein, dye-labeled bovine serum albumin, and dye-labeled DNA, are used as the gain medium and attached to the surface of a ring resonator via surface immobilization biochemical methods. It is estimated that the surface density of the gain molecules is on the order of 10(12) cm(-2), sufficient for lasing under pulsed optical excitation. It is further shown that the optofluidic laser can be tuned by energy transfer mechanisms through biomolecular interactions. This work not only opens a door to novel photonic devices that can be controlled at the level of a single molecular layer but also provides a promising sensing platform to analyze biochemical processes at the solid-liquid interface.

  14. Measuring Student Gains in Understanding the Process of Scientific Research

    NASA Astrophysics Data System (ADS)

    Rector, Travis A.; Krok, M.; Young, M.

    2011-05-01

    We have developed a "Research-Based Science Education" (RBSE) curriculum in which undergraduate non-science majors participate in authentic astrophysical research in the "astro 101" setting. The primary goal of the RBSE curriculum is to develop a student's understanding of the nature of scientific research; i.e. that science is not just a body of knowledge but a process by which knowledge is gained. The RBSE curriculum is now being tested at seven partner institutions. To measure student gains in understanding the process of scientific research we use a modified concept mapping methodology. We will present the methodology, identified student misconceptions about the process of science, and initial results on measured student gains. This work is supported through NSF DUE-CCLI grant 0920293.

  15. Derivation of sideband gain ratio for Herschel/HIFI

    NASA Astrophysics Data System (ADS)

    Kester, Do; Higgins, Ronan; Teyssier, David

    2017-03-01

    Context. Heterodyne mixers are commonly used for high-resolution spectroscopy at radio telescopes. When used as a double sideband system, the accurate flux calibration of spectral lines acquired by those detectors is highly dependent on the system gains in the respective mixer sidebands via the so-called sideband gain ratio (SBR). As such, the SBR was one of the main contributors to the calibration uncertainty budget of the Herschel/HIFI instrument. Aims: We want to determine the HIFI instrument sideband gain ratio for all bands on a fine frequency grid and within an accuracy of a few percent. Methods: We introduce a novel technique involving in-orbit HIFI data that is bootstrapped onto standard methods involving laboratory data measurements of the SBR. We deconvolved the astronomical data to provide a proxy of the expected signal at every frequency channel, and extracted the sideband gain ratios from the residuals of that process. Results: We determine the HIFI sideband gain ratio to an accuracy varying between 1 and 4%, with degraded accuracy in higher frequency ranges, and at places where the reliability of the technique is lower. These figures were incorporated into the HIFI data processing pipeline and improved the overall flux uncertainty of the legacy data from this instrument. Conclusions: We demonstrate that a modified sideband deconvolution algorithm, using astronomical data in combination with gas cell measurements, can be used to generate an accurate and fine-granularity picture of the sideband gain ratio behaviour of a heterodyne receiver. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

  16. Gain Control Network Conditions in Early Sensory Coding

    PubMed Central

    Serrano, Eduardo; Nowotny, Thomas; Levi, Rafael; Smith, Brian H.; Huerta, Ramón

    2013-01-01

    Gain control is essential for the proper function of any sensory system. However, the precise mechanisms for achieving effective gain control in the brain are unknown. Based on our understanding of the existence and strength of connections in the insect olfactory system, we analyze the conditions that lead to controlled gain in a randomly connected network of excitatory and inhibitory neurons. We consider two scenarios for the variation of input into the system. In the first case, the intensity of the sensory input controls the input currents to a fixed proportion of neurons of the excitatory and inhibitory populations. In the second case, increasing intensity of the sensory stimulus will both, recruit an increasing number of neurons that receive input and change the input current that they receive. Using a mean field approximation for the network activity we derive relationships between the parameters of the network that ensure that the overall level of activity of the excitatory population remains unchanged for increasing intensity of the external stimulation. We find that, first, the main parameters that regulate network gain are the probabilities of connections from the inhibitory population to the excitatory population and of the connections within the inhibitory population. Second, we show that strict gain control is not achievable in a random network in the second case, when the input recruits an increasing number of neurons. Finally, we confirm that the gain control conditions derived from the mean field approximation are valid in simulations of firing rate models and Hodgkin-Huxley conductance based models. PMID:23874176

  17. Coding gains and error rates from the Big Viterbi Decoder

    NASA Technical Reports Server (NTRS)

    Onyszchuk, I. M.

    1991-01-01

    A prototype hardware Big Viterbi Decoder (BVD) was completed for an experiment with the Galileo Spacecraft. Searches for new convolutional codes, studies of Viterbi decoder hardware designs and architectures, mathematical formulations, and decompositions of the deBruijn graph into identical and hierarchical subgraphs, and very large scale integration (VLSI) chip design are just a few examples of tasks completed for this project. The BVD bit error rates (BER), measured from hardware and software simulations, are plotted as a function of bit signal to noise ratio E sub b/N sub 0 on the additive white Gaussian noise channel. Using the constraint length 15, rate 1/4, experimental convolutional code for the Galileo mission, the BVD gains 1.5 dB over the NASA standard (7,1/2) Maximum Likelihood Convolution Decoder (MCD) at a BER of 0.005. At this BER, the same gain results when the (255,233) NASA standard Reed-Solomon decoder is used, which yields a word error rate of 2.1 x 10(exp -8) and a BER of 1.4 x 10(exp -9). The (15, 1/6) code to be used by the Cometary Rendezvous Asteroid Flyby (CRAF)/Cassini Missions yields 1.7 dB of coding gain. These gains are measured with respect to symbols input to the BVD and increase with decreasing BER. Also, 8-bit input symbol quantization makes the BVD resistant to demodulated signal-level variations which may cause higher bandwidth than the NASA (7,1/2) code, these gains are offset by about 0.1 dB of expected additional receiver losses. Coding gains of several decibels are possible by compressing all spacecraft data.

  18. Weight Gain following Pallidal Deep Brain Stimulation: A PET Study.

    PubMed

    Sauleau, Paul; Drapier, Sophie; Duprez, Joan; Houvenaghel, Jean-François; Dondaine, Thibaut; Haegelen, Claire; Drapier, Dominique; Jannin, Pierre; Robert, Gabriel; Le Jeune, Florence; Vérin, Marc

    2016-01-01

    The mechanisms behind weight gain following deep brain stimulation (DBS) surgery seem to be multifactorial and suspected depending on the target, either the subthalamic nucleus (STN) or the globus pallidus internus (GPi). Decreased energy expenditure following motor improvement and behavioral and/or metabolic changes are possible explanations. Focusing on GPi target, our objective was to analyze correlations between changes in brain metabolism (measured with PET) and weight gain following GPi-DBS in patients with Parkinson's disease (PD). Body mass index was calculated and brain activity prospectively measured using 2-deoxy-2[18F]fluoro-D-glucose PET four months before and four months after the start of GPi-DBS in 19 PD patients. Dopaminergic medication was included in the analysis to control for its possible influence on brain metabolism. Body mass index increased significantly by 0.66 ± 1.3 kg/m2 (p = 0.040). There were correlations between weight gain and changes in brain metabolism in premotor areas, including the left and right superior gyri (Brodmann area, BA 6), left superior gyrus (BA 8), the dorsolateral prefrontal cortex (right middle gyrus, BAs 9 and 46), and the left and right somatosensory association cortices (BA 7). However, we found no correlation between weight gain and metabolic changes in limbic and associative areas. Additionally, there was a trend toward a correlation between reduced dyskinesia and weight gain (r = 0.428, p = 0.067). These findings suggest that, unlike STN-DBS, motor improvement is the major contributing factor for weight gain following GPi-DBS PD, confirming the motor selectivity of this target.

  19. Weight Gain following Pallidal Deep Brain Stimulation: A PET Study

    PubMed Central

    Sauleau, Paul; Drapier, Sophie; Duprez, Joan; Houvenaghel, Jean-François; Dondaine, Thibaut; Haegelen, Claire; Drapier, Dominique; Jannin, Pierre; Robert, Gabriel; Le Jeune, Florence; Vérin, Marc

    2016-01-01

    The mechanisms behind weight gain following deep brain stimulation (DBS) surgery seem to be multifactorial and suspected depending on the target, either the subthalamic nucleus (STN) or the globus pallidus internus (GPi). Decreased energy expenditure following motor improvement and behavioral and/or metabolic changes are possible explanations. Focusing on GPi target, our objective was to analyze correlations between changes in brain metabolism (measured with PET) and weight gain following GPi-DBS in patients with Parkinson’s disease (PD). Body mass index was calculated and brain activity prospectively measured using 2-deoxy-2[18F]fluoro-D-glucose PET four months before and four months after the start of GPi-DBS in 19 PD patients. Dopaminergic medication was included in the analysis to control for its possible influence on brain metabolism. Body mass index increased significantly by 0.66 ± 1.3 kg/m2 (p = 0.040). There were correlations between weight gain and changes in brain metabolism in premotor areas, including the left and right superior gyri (Brodmann area, BA 6), left superior gyrus (BA 8), the dorsolateral prefrontal cortex (right middle gyrus, BAs 9 and 46), and the left and right somatosensory association cortices (BA 7). However, we found no correlation between weight gain and metabolic changes in limbic and associative areas. Additionally, there was a trend toward a correlation between reduced dyskinesia and weight gain (r = 0.428, p = 0.067). These findings suggest that, unlike STN-DBS, motor improvement is the major contributing factor for weight gain following GPi-DBS PD, confirming the motor selectivity of this target. PMID:27070317

  20. Caustic Singularities Of High-Gain, Dual-Shaped Reflectors

    NASA Technical Reports Server (NTRS)

    Galindo, Victor; Veruttipong, Thavath W.; Imbriale, William A.; Rengarajan, Sambiam

    1991-01-01

    Report presents study of some sources of error in analysis, by geometric theory of diffraction (GTD), of performance of high-gain, dual-shaped antenna reflector. Study probes into underlying analytic causes of singularity, with view toward devising and testing practical methods to avoid problems caused by singularity. Hybrid physical optics (PO) approach used to study near-field spillover or noise-temperature characteristics of high-gain relector antenna efficiently and accurately. Report illustrates this approach and underlying principles by presenting numerical results, for both offset and symmetrical reflector systems, computed by GTD, PO, and PO/GO methods.

  1. Pseudotumor Cerebri and Implanon: Is Rapid Weight Gain the Trigger?

    PubMed Central

    Kassen, Nirusha; Wells, Cait-lynn; Moodley, Anand

    2015-01-01

    Abstract The relationship between pseudotumor cerebri and contraceptive drugs is controversial. Its association with Implanon, an implantable single-rod contraceptive containing etonogestrel (a progestogen) has not been reported but is the subject of many medico-legal cases. The authors present two case reports of patients using Implanon and who subsequently developed pseudotumor cerebri. Rapid weight gain rather than direct hormonal influence is probably the trigger. Headaches, visual obscurations, and rapid weight gain in patients using Implanon should alert one to the probable diagnosis of pseudotumor cerebri. PMID:27928370

  2. Pseudotumor Cerebri and Implanon: Is Rapid Weight Gain the Trigger?

    PubMed

    Kassen, Nirusha; Wells, Cait-Lynn; Moodley, Anand

    2015-12-01

    The relationship between pseudotumor cerebri and contraceptive drugs is controversial. Its association with Implanon, an implantable single-rod contraceptive containing etonogestrel (a progestogen) has not been reported but is the subject of many medico-legal cases. The authors present two case reports of patients using Implanon and who subsequently developed pseudotumor cerebri. Rapid weight gain rather than direct hormonal influence is probably the trigger. Headaches, visual obscurations, and rapid weight gain in patients using Implanon should alert one to the probable diagnosis of pseudotumor cerebri.

  3. Effective gain measurements in chromium-doped forsterite

    NASA Technical Reports Server (NTRS)

    Petricevic, V.; Seas, A.; Alfano, R. R.

    1991-01-01

    Effective gain cross section in tetravalent chromium-doped forsterite laser crystal was measured over the 1180-1330 nm spectral range. The experiment was performed using two collinear laser beams in a pump-and-probe arrangement. The peak-gain cross section from this measurement is estimated to be 1.9 x 10 to the -19th sq cm at 1215 nm, which is comparable to the value of about 2 x 10 to the -19th sq cm predicted by fluorescence linewidth and lifetime measurements. These results indicate that excited-state absorption is not a major loss mechanism in tetravalent chromium-doped forsterite.

  4. High gain multigap avalanche detectors for Cerenkov ring imaging

    SciTech Connect

    Gilmore, R.S.; Lavender, W.M.; Leith, D.W.G.S.; Williams, S.H.

    1980-10-01

    We report on a continuing study of multigap parallel plate avalanche chambers, primarily as photoelectron detectors for use with Cerenkov ring imaging counters. By suitable control of the fields in successive gaps and by introducing screens to reduce photon feedback to the cathode the gain many be increased considerably. We have obtained gains in excess of 6 x 10/sup 7/ for photoelectrons with a good pulse height spectrum and expect to increase this further. We discuss the use of resistive anodes to give avalanche positions in two dimensions by charge division.

  5. Use solar energy for remote antenna gain measurements

    SciTech Connect

    Doty, A.

    1988-06-01

    A new method for solar antenna gain measurements is proposed which is independent of the effective input system temperature. The method is based on the difference between two power measurements, the Dp factor, and requires little equipment. A spectrum analyzer that has an average noise-measurement mode calibrated in power/bandwidth (dBm/Hz) is connected to the output of a radar receiver's front-end low-noise amplifier (LNA), where it detects the system's noise levels. No other equipment is required, assuming that the RF loss between the LNA and the antenna terminal and the gain of the LNA are known. An example of calculations is given.

  6. Limits to the information gain from lidar measurements.

    PubMed

    Belmonte, Aniceto

    2015-04-15

    Measurements over the return signal are an integral part of lidar remote sensing by which we gather information about the characteristics of specific targets. But how much information is gained by performing a given lidar measurement? By defining Shannon's mutual information of a lidar observation, here we consider the bits of information content on the measurement and describe mathematically the capacity of lidar estimates to represent a corresponding property in the target. For heterodyne Doppler lidars in particular, we have found simple analytical formulas that consider the information gain in mean-frequency estimates.

  7. Gain-switched holmium-doped fibre laser.

    PubMed

    Wu, Ka S; Ottaway, David; Munch, Jesper; Lancaster, David G; Bennetts, Shayne; Jackson, Stuart D

    2009-11-09

    We demonstrate the first gain-switched, singly doped, single-mode holmium-doped silicate glass fibre laser that operates at 2.106 microm. Using a gain-switched 1.909-microm thulium-doped fibre laser as the pump source, output pulses of energy 3.2 microJ and pulse duration of 150 ns were generated at 80 kHz and slope efficiency of 44%. Pulse stacking within the holmium-doped fibre laser resulted in significantly shorter 70 ns pulses.

  8. Photonic band-edge micro lasers with quantum dot gain.

    PubMed

    Nomura, Masahiro; Iwamoto, Satoshi; Tandaechanurat, Aniwat; Ota, Yasutomo; Kumagai, Naoto; Arakawa, Yasuhiko

    2009-01-19

    We demonstrate optically pumped continuous-wave photonic band-edge microlasers on a two-dimensional photonic crystal slab. Lasing was observed at a photonic band-edge, where the group velocity was significantly small near the K point of the band structure having a triangular lattice. Lasing was achieved by using a quantum dot gain material, which resulted in a significant decrease in the laser threshold, compared with photonic band-edge lasers using quantum well gain material. Extremely low laser thresholds of approximately 80 nW at 6 K was achieved. Lasing was observed in a defect-free photonic crystal as small as approximately 7 microm square.

  9. Gain-Compensating Circuit For NDE and Ultrasonics

    NASA Technical Reports Server (NTRS)

    Kushnick, Peter W.

    1987-01-01

    High-frequency gain-compensating circuit designed for general use in nondestructive evaluation and ultrasonic measurements. Controls gain of ultrasonic receiver as function of time to aid in measuring attenuation of samples with high losses; for example, human skin and graphite/epoxy composites. Features high signal-to-noise ratio, large signal bandwidth and large dynamic range. Control bandwidth of 5 MHz ensures accuracy of control signal. Currently being used for retrieval of more information from ultrasonic signals sent through composite materials that have high losses, and to measure skin-burn depth in humans.

  10. A large area, high gain Micro Gap Chamber

    NASA Astrophysics Data System (ADS)

    Angelini, F.; Bellazzini, R.; Bozzo, M.; Brez, A.; Massai, M. M.; Raffo, R.; Spandre, G.; Spezziga, M.; Toropin, A.

    1995-02-01

    A new approach to the construction of the Micro Gap Chamber is presented. A 10 × 10 cm 2 MGC has been built using a 8 μm thick polyimide layer as anode-cathode insulator. Studies on gas gain, uniformity of response along the strip and charging-up have been carried out in laboratory by using X-ray sources. Very large proportional gains, up to ˜ 210 4, have been reached working with gas mixtures based on Ne-DME. The simplified technology for the detector fabrication opens the possibility to produce very large area MGCs.

  11. Informant Agreement in Treatment Gains for Child Anxiety

    ERIC Educational Resources Information Center

    Benjamin, Courtney L.; Puleo, Connor M.; Kendall, Philip C.

    2011-01-01

    The present study examined multiple informant agreement in reports of treatment gains in a sample of children (M age = 10.27) treated for social phobia, generalized anxiety disorder, and separation anxiety disorder. Mothers and fathers agreed on their child's improvement, and parents and children also generally agreed on the child's improvement.…

  12. Experience gained from treating facial injuries due to civil unrest

    PubMed Central

    Whitlock, R I H

    1981-01-01

    During the past 10 years of civil unrest in Northern Ireland a wide variety of facial injuries have been treated at the Royal Victoria Hospital, Belfast. The causes and nature of these injuries are described and the experience gained in their management is reviewed. Imagesp[35]-ap[42]-aFig. 1Fig. 3Fig. 4Fig. 5Fig. 6Fig. 7 PMID:7247260

  13. Flexible Contrast Gain Control in the Right Hemisphere

    ERIC Educational Resources Information Center

    Okubo, Matia; Nicholls, Michael E. R.

    2005-01-01

    This study investigates whether the right hemisphere has more flexible contrast gain control settings for the identification of spatial frequency. Right-handed participants identified 1 and 9 cycles per degree sinusoidal gratings presented either to the left visual field-right hemisphere (LVF-RH) or the right visual field-left hemisphere (RVF-LH).…

  14. 18 CFR 11.13 - Energy gains calculations.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Energy gains calculations. 11.13 Section 11.13 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER THE FEDERAL POWER ACT ANNUAL CHARGES UNDER PART I OF...

  15. 18 CFR 11.13 - Energy gains calculations.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Energy gains calculations. 11.13 Section 11.13 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER THE FEDERAL POWER ACT ANNUAL CHARGES UNDER PART I OF...

  16. On Point Designs for High Gain Fast Ignition

    SciTech Connect

    Key, M; Akli, K; Beg, F; Betti, R; Clark, D S; Chen, S N; Freeman, R R; Hansen, S; Hatchett, S P; Hey, D; King, J A; Kemp, A J; Lasinski, B F; Langdon, B; Ma, T; MacKinnon, A J; Meyerhofer, D; Patel, P K; Pasley, J; Phillips, T; Stephens, R B; Stoeckl, C; Foord, M; Tabak, M; Theobald, W; Storm, M; Town, R J; Wilks, S C; VanWoerkom, L; Wei, M S; Weber, R; Zhang, B

    2007-09-27

    Fast ignition research has reached the stage where point designs are becoming crucial to the identification of key issues and the development of projects to demonstrate high gain fast ignition. The status of point designs for cone coupled electron fast ignition and some of the issues they highlight are discussed.

  17. Theory of gain in group-III nitride lasers

    SciTech Connect

    Chow, W.W.; Wright, A.F.; Girndt, A.

    1997-06-01

    A microscopic theory of gain in a group-III nitride quantum well laser is presented. The approach, which treats carrier correlations at the level of quantum kinetic theory, gives a consistent account of plasma and excitonic effects in an inhomogeneously broadened system.

  18. A behavioral intervention to reduce excessive gestational weight gain

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Excessive gestational weight gain (GWG) is a key modifiable risk factor for negative maternal and child health. We examined the efficacy of a behavioral intervention in preventing excessive GWG. 230 participants (87.8% Caucasian, mean age= 29.1 years; second parity) completed the 36 week gestational...

  19. Neural mechanisms of gain-loss asymmetry in temporal discounting.

    PubMed

    Tanaka, Saori C; Yamada, Katsunori; Yoneda, Hiroyasu; Ohtake, Fumio

    2014-04-16

    Humans typically discount future gains more than losses. This phenomenon is referred to as the "sign effect" in experimental and behavioral economics. Although recent studies have reported associations between the sign effect and important social problems, such as obesity and incurring multiple debts, the biological basis for this phenomenon remains poorly understood. Here, we hypothesized that enhanced loss-related neural processing in magnitude and/or delay representation are causes of the sign effect. We examined participants performing intertemporal choice tasks involving future gains or losses and compared the brain activity of those who exhibited the sign effect and those who did not. When predicting future losses, significant differences were apparent between the two participant groups in terms of striatal activity representing delay length and in insular activity representing sensitivity to magnitude. Furthermore, participants with the sign effect exhibited a greater insular response to the magnitude of loss than to that of gain, and also a greater striatal response to the delay of loss than to that of gain. These findings may provide a new biological perspective for the development of novel treatments and preventive measures for social problems associated with the sign effect.

  20. Gains from Trade for Nonmaterialists, Environmentalists, and the Overworked

    ERIC Educational Resources Information Center

    Weber, Christian E.

    2007-01-01

    The author proposes an alternative to the traditional definition of the gains from international trade and, hence, an alternative defense of free trade. Rather than showing that free trade allows a country to consume more of all final goods, the author's approach shows that free trade allows a country to consume the same basket of final goods that…

  1. Reward processing in gain versus loss context: An ERP study.

    PubMed

    Zheng, Ya; Li, Qi; Zhang, Yuanyuan; Li, Qi; Shen, Huijuan; Gao, Qianhui; Zhou, Shiyu

    2017-03-23

    Previous research has shown that consummatory ERP components are sensitive to contextual valence. The present study investigated the contextual valence effect across anticipatory and consummatory phases by requiring participants to play a simple gambling task during a gain context and a loss context. During the anticipatory phase, the cue-P3 was more positive in the gain context compared to the loss context, whereas the stimulus-preceding negativity (SPN) was comparable across the two contexts. With respect to the consummatory phase, the feedback-related negativity (FRN) in response to the zero-value outcome was more negative in the gain versus loss context, whereas the feedback P3 (fb-P3) in response to the zero-value outcome was insensitive to contextual valence. These findings suggest that contextual valence effect occurs at a relative early stage of both the reward anticipation and consumption. Moreover, across the gain and loss contexts, the SPN was selectively correlated with the FRN, whereas the cue-P3 was selectively associated with the fb-P3, pointing to a close association between the anticipatory and consummatory phases in reward dynamics.

  2. 26 CFR 7.105-2 - Substantial gainful activity.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ..., institutional therapy or training, school attendance, clubs, social programs, and similar activities is not substantial gainful activity. However, the nature of the work performed may be evidence of ability to engage... the nature of the duties performed, may establish a taxpayer's ability to engage in...

  3. Cognitive adaptation of sonar gain control in the bottlenose dolphin.

    PubMed

    Kloepper, Laura N; Smith, Adam B; Nachtigall, Paul E; Buck, John R; Simmons, James A; Pacini, Aude F

    2014-01-01

    Echolocating animals adjust the transmit intensity and receive sensitivity of their sonar in order to regulate the sensation level of their echoes; this process is often termed automatic gain control. Gain control is considered not to be under the animal's cognitive control, but previous investigations studied animals ensonifying targets or hydrophone arrays at predictable distances. To test whether animals maintain gain control at a fixed level in uncertain conditions, we measured changes in signal intensity for a bottlenose dolphin (Tursiops truncatus) detecting a target at three target distances (2.5, 4 and 7 m) in two types of sessions: predictable and unpredictable. Predictable sessions presented the target at a constant distance; unpredictable sessions moved the target randomly between the three target positions. In the predictable sessions the dolphin demonstrated intensity distance compensation, increasing the emitted click intensity as the target distance increased. Additionally, as trials within sessions progressed, the animal adjusted its click intensity even from the first click in a click train, which is consistent with the animal expecting a target at a certain range. In the unpredictable sessions there was no significant difference of intensity with target distance until after the 7th click in a click train. Together, these results demonstrate that the bottlenose dolphin uses learning and expectation for sonar gain control.

  4. 26 CFR 1.1247-3 - Treatment of capital gains.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... pursuant to section 1247(a) is in effect for a taxable year of a foreign investment company, the company... gains and losses. Generally, the adjusted basis of property held by a foreign investment company shall... property held by a foreign investment company on the first day of the first taxable year for which...

  5. 26 CFR 1.1247-3 - Treatment of capital gains.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... currently pursuant to section 1247(a) is in effect for a taxable year of a foreign investment company, the... computing capital gains and losses. Generally, the adjusted basis of property held by a foreign investment... respect of property held by a foreign investment company on the first day of the first taxable year...

  6. Perceptions of Science Graduating Students on Their Learning Gains

    ERIC Educational Resources Information Center

    Varsavsky, Cristina; Matthews, Kelly E.; Hodgson, Yvonne

    2014-01-01

    In this study, the Science Student Skills Inventory was used to gain understanding of student perceptions about their science skills set developed throughout their programme (scientific content knowledge, communication, scientific writing, teamwork, quantitative skills, and ethical thinking). The study involved 400 responses from undergraduate…

  7. Feature-based attention enhances performance by increasing response gain

    PubMed Central

    Herrmann, Katrin; Heeger, David J.; Carrasco, Marisa

    2012-01-01

    Covert spatial attention can increase contrast sensitivity either by changes in contrast gain or by changes in response gain, depending on the size of the attention field and the size of the stimulus (Herrmann, Montaser-Kouhsari, Carrasco, & Heeger, 2010), as predicted by the normalization model of attention (Reynolds & Heeger, 2009). For feature-based attention, unlike spatial attention, the model predicts only changes in response gain, regardless of whether the featural extent of the attention field is small or large. To test this prediction, we measured the contrast dependence of feature-based attention. Observers performed an orientation-discrimination task on a spatial array of grating patches. The spatial locations of the gratings were varied randomly so that observers could not attend to specific locations. Feature-based attention was manipulated with a 75% valid and 25% invalid pre-cue, and the featural extent of the attention field was manipulated by introducing uncertainty about the upcoming grating orientation. Performance accuracy was better for valid than for invalid pre-cues, consistent with a change in response gain, when the featural extent of the attention field was small (low uncertainty) or when it was large (high uncertainty) relative to the featural extent of the stimulus. These results for feature-based attention clearly differ from results of analogous experiments with spatial attention, yet both support key predictions of the normalization model of attention. PMID:22580017

  8. Score Gains on "g"-Loaded Tests: No "g"

    ERIC Educational Resources Information Center

    te Nijenhuis, Jan; van Vianen, Annelies E. M.; van der Flier, Henk

    2007-01-01

    IQ scores provide the best general predictor of success in education, job training, and work. However, there are many ways in which IQ scores can be increased, for instance by means of retesting or participation in learning potential training programs. What is the nature of these score gains? Jensen [Jensen, A. R. (1998a). "The g factor: The…

  9. Identifying physiological gains in the historic Midwest soybean germplasm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soybean yields in the US have steadily increased throughout the past century due to advances made in breeding and management practices. Despite these historical gains, producers will face a significant challenge to provide sufficient food, fiber, and fuel to supply a growing world population, which ...

  10. Identifying physiological gains in the historic Midwest soybean germplasm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soybean yields in the US have steadily increased throughout the past century due to advances made in breeding and management practices. Despite these historical gains, world food production must increase by 50% by 2030 to meet population demands according to the UN, raising the question of whether t...

  11. Degradation mechanisms of current gain in NPN transistors

    NASA Astrophysics Data System (ADS)

    Li, Xing-Ji; Geng, Hong-Bin; Lan, Mu-Jie; Yang, De-Zhuang; He, Shi-Yu; Liu, Chao-Ming

    2010-06-01

    An investigation of ionization and displacement damage in silicon NPN bipolar junction transistors (BJTs) is presented. The transistors were irradiated separately with 90-keV electrons, 3-MeV protons and 40-MeV Br ions. Key parameters were measured in-situ and the change in current gain of the NPN BJTS was obtained at a fixed collector current (Ic = 1 mA). To characterise the radiation damage of NPN BJTs, the ionizing dose Di and displacement dose Dd as functions of chip depth in the NPN BJTs were calculated using the SRIM and Geant4 code for protons, electrons and Br ions, respectively. Based on the discussion of the radiation damage equation for current gain, it is clear that the current gain degradation of the NPN BJTs is sensitive to both ionization and displacement damage. The degradation mechanism of the current gain is related to the ratio of Dd/(Dd + Di) in the sensitive region given by charged particles. The irradiation particles leading to lower Dd/(Dd + Di) within the same chip depth at a given total dose would mainly produce ionization damage to the NPN BJTs. On the other hand, the charged particles causing larger Dd/(Dd + Di) at a given total dose would tend to generate displacement damage to the NPN BJTs. The Messenger-Spratt equation could be used to describe the experimental data for the latter case.

  12. Radiation Response of Emerging High Gain, Low Noise Detectors

    NASA Technical Reports Server (NTRS)

    Becker, Heidi N.; Farr, William H; Zhu, David Q.

    2007-01-01

    Data illustrating the radiation response of emerging high gain, low noise detectors are presented. Ionizing dose testing of silicon internal discrete avalanche photodiodes, and 51-MeV proton testing of InGaAs/InAlAs avalanche photodiodes operated in Geiger mode are discussed.

  13. 75 FR 66708 - Program Integrity: Gainful Employment; Correction

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-29

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF EDUCATION 34 CFR Part 668 RIN 1840-AD04 Program Integrity: Gainful Employment; Correction AGENCY: Office of Postsecondary Education, Department of Education ACTION: Notice of public meeting sessions; correction....

  14. 75 FR 66665 - Program Integrity: Gainful Employment-New Programs

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-29

    ... educational opportunities crucial to employment. For- profit postsecondary education along with occupationally... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF EDUCATION 34 CFR Part 600 RIN 1840-AD04 Program Integrity: Gainful Employment--New Programs AGENCY: Office...

  15. Acoustics of fish shelters: frequency response and gain properties.

    PubMed

    Lugli, Marco

    2012-11-01

    Many teleosts emit sounds from cavities beneath stones and other types of submerged objects, yet the acoustical properties of fish shelters are virtually unexplored. This study examines the gain properties of shelters commonly used by Mediterranean gobies as hiding places and/or nest sites in the field (flat stones, shells belonging to five bivalve species), or within aquarium tanks (tunnel-shaped plastic covers, concrete blocks, concrete cylinder pipe, halves of terracotta flower pots). All shelters were acoustically stimulated using a small underwater buzzer, placed inside or around the shelter to mimic a fish calling from the nest site, and different types of driving stimuli (white noise, pure tones, and artificial pulse trains). Results showed the presence of significant amplitude gain (3-18 dB) at frequencies in the range 100-150 Hz in all types of natural shelters but one (Mytilus), terracotta flower pots, and concrete blocks. Gain was higher for stones and artificial shelters than for shells. Gain peak amplitude increased with the weight of stones and shells. Conclusions were verified by performing analogous acoustical tests on flat stones in the stream. Results draw attention to the use of suitable shelters for proper recording of sounds produced by fishes kept within laboratory aquaria.

  16. Cognitive Adaptation of Sonar Gain Control in the Bottlenose Dolphin

    PubMed Central

    Kloepper, Laura N.; Smith, Adam B.; Nachtigall, Paul E.; Buck, John R.; Simmons, James A.; Pacini, Aude F.

    2014-01-01

    Echolocating animals adjust the transmit intensity and receive sensitivity of their sonar in order to regulate the sensation level of their echoes; this process is often termed automatic gain control. Gain control is considered not to be under the animal's cognitive control, but previous investigations studied animals ensonifying targets or hydrophone arrays at predictable distances. To test whether animals maintain gain control at a fixed level in uncertain conditions, we measured changes in signal intensity for a bottlenose dolphin (Tursiops truncatus) detecting a target at three target distances (2.5, 4 and 7 m) in two types of sessions: predictable and unpredictable. Predictable sessions presented the target at a constant distance; unpredictable sessions moved the target randomly between the three target positions. In the predictable sessions the dolphin demonstrated intensity distance compensation, increasing the emitted click intensity as the target distance increased. Additionally, as trials within sessions progressed, the animal adjusted its click intensity even from the first click in a click train, which is consistent with the animal expecting a target at a certain range. In the unpredictable sessions there was no significant difference of intensity with target distance until after the 7th click in a click train. Together, these results demonstrate that the bottlenose dolphin uses learning and expectation for sonar gain control. PMID:25153530

  17. 20 CFR 404.1510 - Meaning of substantial gainful activity.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 2 2014-04-01 2014-04-01 false Meaning of substantial gainful activity. 404.1510 Section 404.1510 Employees' Benefits SOCIAL SECURITY ADMINISTRATION FEDERAL OLD-AGE, SURVIVORS AND DISABILITY INSURANCE (1950- ) Determining Disability and Blindness Definition of Disability §...

  18. 20 CFR 404.1510 - Meaning of substantial gainful activity.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 2 2012-04-01 2012-04-01 false Meaning of substantial gainful activity. 404.1510 Section 404.1510 Employees' Benefits SOCIAL SECURITY ADMINISTRATION FEDERAL OLD-AGE, SURVIVORS AND DISABILITY INSURANCE (1950- ) Determining Disability and Blindness Definition of Disability §...

  19. 20 CFR 404.1510 - Meaning of substantial gainful activity.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 2 2011-04-01 2011-04-01 false Meaning of substantial gainful activity. 404.1510 Section 404.1510 Employees' Benefits SOCIAL SECURITY ADMINISTRATION FEDERAL OLD-AGE, SURVIVORS AND DISABILITY INSURANCE (1950- ) Determining Disability and Blindness Definition of Disability §...

  20. 20 CFR 404.1510 - Meaning of substantial gainful activity.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Meaning of substantial gainful activity. 404.1510 Section 404.1510 Employees' Benefits SOCIAL SECURITY ADMINISTRATION FEDERAL OLD-AGE, SURVIVORS AND DISABILITY INSURANCE (1950- ) Determining Disability and Blindness Definition of Disability §...

  1. 20 CFR 404.1510 - Meaning of substantial gainful activity.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 2 2013-04-01 2013-04-01 false Meaning of substantial gainful activity. 404.1510 Section 404.1510 Employees' Benefits SOCIAL SECURITY ADMINISTRATION FEDERAL OLD-AGE, SURVIVORS AND DISABILITY INSURANCE (1950- ) Determining Disability and Blindness Definition of Disability §...

  2. The Cinderella Effect: Does Athletic Success Translate into Advancement Gains?

    ERIC Educational Resources Information Center

    DiConsiglio, John

    2012-01-01

    In this article, the author explores how athletic success translates into advancement gains. He shares the Cinderella story of the Butler University's Butler Bulldogs which became the prototypical college sports Cinderella during its star turn in the 2010 tournament. Many institutions say that their athletic accomplishments have brought them…

  3. High-Stakes Testing Hasn't Brought Education Gains

    ERIC Educational Resources Information Center

    Dianis, Judith Browne; Jackson, John H.; Noguera, Pedro

    2015-01-01

    The only thing that more testing will tell us is what we already know: The schools that disadvantaged children attend are not being given the supports necessary to produce achievement gains. Students cannot be tested out of poverty, and while NCLB did take us a step forward by requiring schools to produce evidence that students were learning, it…

  4. Weight Gain in Zollinger-Ellison Syndrome After Acid Suppression

    PubMed Central

    Riff, Brian P.; Leiman, David A.; Bennett, Bonita; Fraker, Douglas L.; Metz, David C.

    2015-01-01

    Objectives Zollinger-Ellison Syndrome (ZES) is characterized by hypergastrinemia and gastric acid hypersecretion resulting in peptic ulcer disease, diarrhea and weight loss. Acid secretion can be controlled with medication and biochemical cure is possible with surgery. Data on how these interventions affect patients’ weight are lacking. We aimed to determine how medical and surgical acid control affects weight over time. Methods We performed a retrospective cohort study on 60 ZES patients. Acid control was achieved with appropriate dose proton pump inhibitor (PPI) therapy. Surgery was performed for curative intent when appropriate. Weight change was assessed versus pre-acid control or immediate pre-operative weights and expressed as absolute and percent change from baseline at 6, 12, 18 and 24 months. Results A total of 30 PPI-controlled patients and 20 surgery-controlled patients were analyzed. Weight gain was noted at all-time points while on appropriate dose PPI therapy (p<0.005). Of patients who had surgery with curative intent, weight gain was noted at 12 months (7.9%, p=0.013) and 18 months (7.1%, p=0.007). There was a trend toward weight gain seen at all-time points in the patients who were surgically cured. Conclusion These data represent a novel description of weight gain after acid suppression in ZES. PMID:26164604

  5. Feature-based attention enhances performance by increasing response gain.

    PubMed

    Herrmann, Katrin; Heeger, David J; Carrasco, Marisa

    2012-12-01

    Covert spatial attention can increase contrast sensitivity either by changes in contrast gain or by changes in response gain, depending on the size of the attention field and the size of the stimulus (Herrmann et al., 2010), as predicted by the normalization model of attention (Reynolds & Heeger, 2009). For feature-based attention, unlike spatial attention, the model predicts only changes in response gain, regardless of whether the featural extent of the attention field is small or large. To test this prediction, we measured the contrast dependence of feature-based attention. Observers performed an orientation-discrimination task on a spatial array of grating patches. The spatial locations of the gratings were varied randomly so that observers could not attend to specific locations. Feature-based attention was manipulated with a 75% valid and 25% invalid pre-cue, and the featural extent of the attention field was manipulated by introducing uncertainty about the upcoming grating orientation. Performance accuracy was better for valid than for invalid pre-cues, consistent with a change in response gain, when the featural extent of the attention field was small (low uncertainty) or when it was large (high uncertainty) relative to the featural extent of the stimulus. These results for feature-based attention clearly differ from results of analogous experiments with spatial attention, yet both support key predictions of the normalization model of attention.

  6. Steps toward Gaining Knowledge of World Music Pedagogy

    ERIC Educational Resources Information Center

    Carlisle, Katie

    2013-01-01

    This article presents steps toward gaining knowledge of world music pedagogy for K-12 general music educators. The majority of the article details steps that invite engagement within everyday contexts with accessible resources within local and online communities. The steps demonstrate ways general music teachers can diversify and self-direct their…

  7. Young Children's Analogical Problem Solving: Gaining Insights from Video Displays

    ERIC Educational Resources Information Center

    Chen, Zhe; Siegler, Robert S.

    2013-01-01

    This study examined how toddlers gain insights from source video displays and use the insights to solve analogous problems. Two- to 2.5-year-olds viewed a source video illustrating a problem-solving strategy and then attempted to solve analogous problems. Older but not younger toddlers extracted the problem-solving strategy depicted in the video…

  8. [Antipsychotic-induced weight gain--pharmacogenetic studies].

    PubMed

    Olajossy-Hilkesberger, Luiza; Godlewska, Beata; Marmurowska-Michałowskal, Halina; Olajossy, Marcin; Landowski, Jerzy

    2006-01-01

    Drug-naive patients with schizophrenia often present metabolic abnormalities and obesity. Weight gain may be the side effect of treatment with many antipsychotic drugs. Genetic effects, besides many other factors, are known to influence obesity in patients with schizophrenia treated with antipsychotics. Numerous studies of several genes' polymorphisms have been performed. -759C/T polymorphism of 5HT2C gene attracted most attention. In 5 independent studies of this polymorphism the association between T allele with the lower AP-induced weight gain was detected. No associations could be detected between weight gain and other polymorphisms of serotonergic system genes as well as histaminergic system genes. Studies of adrenergic and dopaminergic system have neither produced any unambiguous results. Analysis of the newest candidate genes (SAP-25, leptin gene) confirmed the role of genetic factors in AP-induced weight gain. It is worth emphasising, that the studies have been conducted in relatively small and heterogenic groups and that various treatment strategies were used.

  9. 26 CFR 1.737-1 - Recognition of precontribution gain.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Recognition of precontribution gain. 1.737-1 Section 1.737-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Distributions by A Partnership § 1.737-1 Recognition of...

  10. Who Gains, Who Loses from School Choice: A Research Summary.

    ERIC Educational Resources Information Center

    Fuller, Bruce

    Although the school-choice movement has spread quickly, little time has been taken to assess whether the claimed benefits of school choice have actually been realized. This policy brief summarizes empirical evidence to date and addresses the following questions: Who gains from school choice and who loses? Do innovative school organizations arise…

  11. Explaining Mathematics Achievement Gains in Botswana and South Africa

    ERIC Educational Resources Information Center

    Carnoy, Martin; Arends, Fabian

    2012-01-01

    The purpose of this study is to test empirically whether and how classroom and school factors contribute to student mathematics learning gains in the border region of North West province, South Africa and Southeastern Botswana. Our results suggest that in both regions, improving teaching quality has an important impact on how much mathematics…

  12. Amantadine for weight gain associated with olanzapine treatment.

    PubMed

    Deberdt, Walter; Winokur, Andrew; Cavazzoni, Patrizia A; Trzaskoma, Quynh N; Carlson, Christopher D; Bymaster, Frank P; Wiener, Karen; Floris, Michel; Breier, Alan

    2005-01-01

    Patients with schizophrenia (Sch), schizoaffective, schizophreniform, or bipolar (BP) I disorders [Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV)]; not manic or acutely psychotic [Brief Psychiatric Rating Scale (BPRS) total score < or =45]; treated with olanzapine for 1-24 months; and who had gained > or =5% of their initial body weight were examined to determine whether amantadine could attenuate weight gain or promote weight loss. Olanzapine (Olz; 5-20 mg/day) was co-administered with double-blind treatment of 100-300 mg/day amantadine (Olz+Amt, n=60) or placebo (Olz+Plc, n=65). Visit-wise analysis of weight showed that weight change from baseline [last-observation-carried-forward (LOCF)] in the Olz+Amt group was significantly different from the Olz+Plc group at weeks 8 (P=0.042), 12 (P=0.029), and 16 (primary endpoint, mean+/-S.D.: -0.19+/-4.58 versus 1.28+/-4.26 kg, P=0.045). Mean BPRS total score, positive subscale, and anxiety-depression scores improved comparably in both groups, and Montgomery-Asberg Depression Rating Scale (MADRS) total score improved in the Olz+Amt group. Overall, amantadine was safe, was well tolerated, and attenuated weight gain or promoted weight loss in some patients who had gained weight during olanzapine therapy.

  13. 18 CFR 11.13 - Energy gains calculations.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 18 Conservation of Power and Water Resources 1 2012-04-01 2012-04-01 false Energy gains calculations. 11.13 Section 11.13 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER THE FEDERAL POWER ACT ANNUAL CHARGES UNDER PART I OF...

  14. 18 CFR 11.13 - Energy gains calculations.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 18 Conservation of Power and Water Resources 1 2013-04-01 2013-04-01 false Energy gains calculations. 11.13 Section 11.13 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER THE FEDERAL POWER ACT ANNUAL CHARGES UNDER PART I OF...

  15. 18 CFR 11.13 - Energy gains calculations.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 18 Conservation of Power and Water Resources 1 2014-04-01 2014-04-01 false Energy gains calculations. 11.13 Section 11.13 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER THE FEDERAL POWER ACT ANNUAL CHARGES UNDER PART I OF...

  16. Maternal Behavior and Infant Weight Gain in the First Year

    ERIC Educational Resources Information Center

    Worobey, John; Lopez, Maria Islas; Hoffman, Daniel J.

    2009-01-01

    Objective: To examine the relative contributions of maternal characteristics and behaviors in predicting infant weight gain over the first year of postpartum life. Design: Longitudinal study of maternal feeding style throughout infancy. Setting: A Special Supplemental Nutrition Program for Women, Infants, and Children center. Participants:…

  17. Health Literacy Predicts Cardiac Knowledge Gains in Cardiac Rehabilitation Participants

    ERIC Educational Resources Information Center

    Mattson, Colleen C.; Rawson, Katherine; Hughes, Joel W.; Waechter, Donna; Rosneck, James

    2015-01-01

    Objective: Health literacy is increasingly recognised as a potentially important patient characteristic related to patient education efforts. We evaluated whether health literacy would predict gains in knowledge after completion of patient education in cardiac rehabilitation. Method: This was a re-post observational analysis study design based on…

  18. Cancer Survivors Gain from Web-Based Health Care

    MedlinePlus

    ... 163535.html Cancer Survivors Gain From Web-Based Health Care But some patients reported missing face-to-face ... 10, 2017 (HealthDay News) -- Online- and phone-based health care offers a number of benefits for cancer survivors, ...

  19. Robust Optimal Adaptive Control Method with Large Adaptive Gain

    NASA Technical Reports Server (NTRS)

    Nguyen, Nhan T.

    2009-01-01

    In the presence of large uncertainties, a control system needs to be able to adapt rapidly to regain performance. Fast adaptation is referred to the implementation of adaptive control with a large adaptive gain to reduce the tracking error rapidly. However, a large adaptive gain can lead to high-frequency oscillations which can adversely affect robustness of an adaptive control law. A new adaptive control modification is presented that can achieve robust adaptation with a large adaptive gain without incurring high-frequency oscillations as with the standard model-reference adaptive control. The modification is based on the minimization of the Y2 norm of the tracking error, which is formulated as an optimal control problem. The optimality condition is used to derive the modification using the gradient method. The optimal control modification results in a stable adaptation and allows a large adaptive gain to be used for better tracking while providing sufficient stability robustness. Simulations were conducted for a damaged generic transport aircraft with both standard adaptive control and the adaptive optimal control modification technique. The results demonstrate the effectiveness of the proposed modification in tracking a reference model while maintaining a sufficient time delay margin.

  20. Investigating College Learning Gain: Exploring a Propensity Score Weighting Approach

    ERIC Educational Resources Information Center

    Liu, Ou Lydia; Liu, Huili; Roohr, Katrina Crotts; McCaffrey, Daniel F.

    2016-01-01

    Learning outcomes assessment has been widely used by higher education institutions both nationally and internationally. One of its popular uses is to document learning gains of students. Prior studies have recognized the potential imbalance between freshmen and seniors in terms of their background characteristics and their prior academic…

  1. Variables Affecting L2 Gains during Study Abroad

    ERIC Educational Resources Information Center

    Baker-Smemoe, Wendy; Dewey, Dan P.; Bown, Jennifer; Martinsen, Rob A.

    2014-01-01

    Second language (L2) gains during study abroad have been related to several variables including length of stay (Llanes, 2011), language use (Martinsen, Baker, Dewey, Bown, & Johnson, 2010), and social network development (Isabelli-García, 2006), among others. However, most studies have investigated only a few predictors in single study abroad…

  2. Neural Vulnerability Factors that Increase Risk for Future Weight Gain

    PubMed Central

    Stice, Eric; Yokum, Sonja

    2015-01-01

    Theorists have proposed several neural vulnerability factors that may increase overeating and consequent weight gain. Early cross-sectional imaging studies could not determine whether aberrant neural responsivity was a precursor or consequence of overeating. However, recent prospective imaging studies examining predictors of future weight gain and response to obesity treatment, and repeated-measures imaging studies before and after weight gain and loss have advanced knowledge of etiologic processes and neural plasticity resulting from weight change. The present article reviews evidence from prospective studies using imaging and behavioral measures reflecting neural function, as well as randomized experiments with humans and animals that are consistent or inconsistent with five neural vulnerability theories for excessive weight gain. Extant data provide strong support for the incentive sensitization theory of obesity and moderate support for the reward surfeit theory, inhibitory control deficit theory, and dynamic vulnerability model of obesity, which attempted to synthesize the former theories into a single etiologic model. However, existing data provide only minimal support for the reward deficit theory. Findings are synthesized into a new working etiologic model that is based on current scientific knowledge. Important directions for future studies, which have the potential to support or refute this working etiologic model, are delineated. PMID:26854866

  3. Gain measurements at 5 nm in nickel-like ytterbium

    SciTech Connect

    MacGowan, B.J.; Bourgade, J.L.; Combis, P.; Keane, C.J.; Louis-Jacquet, M.; Matthews, D.L.; Naccache, D.; Stone, G.; Thiell, G.; Whelan, D.A.

    1988-03-01

    Soft x-ray gain has been demonstrated at 5.03 nm within a laser produced plasma of Ni-like ytterbium. Experiments will also be described with higher Z Ni-like ions which can produce even shorter wavelength x-ray laser transition. 3 refs.

  4. Nutritional status and weight gain in pregnant women.

    PubMed

    Sato, Ana Paula Sayuri; Fujimori, Elizabeth

    2012-01-01

    This study described the nutritional status of 228 pregnant women and the influence of this on birth weight. This is a retrospective study, developed in a health center in the municipality of São Paulo, with data obtained from medical records. Linear regression analysis was carried out. An association was verified between the initial and final nutritional status (p<0.001). The mean of total weight gain in the pregnant women who began the pregnancy underweight was higher compared those who started overweight/obese (p=0.005). Weight gain was insufficient for 43.4% of the pregnant women with adequate initial weight and for 36.4% of all the pregnant women studied. However, 37.1% of those who began the pregnancy overweight/obese finished with excessive weight gain, a condition that ultimately affected almost a quarter of the pregnant women. Anemia and low birth weight were uncommon, however, in the linear regression analysis, birth weight was associated with weight gain (p<0.05). The study highlights the importance of nutritional care before and during pregnancy to promote maternal-infant health.

  5. An Assessment of Potential Efficiency Gains through Online Content Use

    ERIC Educational Resources Information Center

    Creaser, Claire; Hamblin, Yvonne; Davies, J. Eric

    2006-01-01

    Purpose: Online content has largely replaced traditional print-based resources as the primary tool for literature searching throughout much of the academic and research community. This paper presents the results of a small-scale study, commissioned by the JISC in 2004, to assess the potential efficiency gains that may be achieved through the use…

  6. Understanding Satellite Characterization Knowledge Gained from Radiometric Data

    DTIC Science & Technology

    2011-09-01

    UNDERSTANDING SATELLITE CHARACTERIZATION KNOWLEDGE GAINED FROM RADIOMETRIC DATA Andrew Harms Princeton University Kris Hamada, Charles J. Wetterer...framework for determining satellite characterization knowledge, in the form of estimated parameter uncertainties, from radiometric observation type...uncer- tainties into satellite characterization parameter space. These parameters can include size, shape, orientation, material properties, etc., and

  7. Gaining Empowerment Allows Results [G.E.A.R.

    ERIC Educational Resources Information Center

    Reclaiming Children and Youth, 2011

    2011-01-01

    Gaining Empowerment Allows Results (G.E.A.R.) is a parent-run organization for families facing challenges due to children with emotional and behavioral health concerns. These parents are able to network with other families and learn about resources for their family. A wide range of services include telephone support, monthly family support groups,…

  8. One-Minute Paper: Student Perception of Learning Gains

    ERIC Educational Resources Information Center

    Anderson, Deborah; Burns, Shari

    2013-01-01

    The purpose of this study was to determine students' perceptions of learning gains when using the one-minute paper. Thirty-one students from the Physical Therapy (PT) and Nurse Anesthesia (NA) programs participated in this study. Students completed the one-minute paper in three classes. An email to students clarified the "muddy" points…

  9. Weight gain increases human aromatase expression in mammary gland.

    PubMed

    Chen, Dong; Zhao, Hong; Coon, John S; Ono, Masanori; Pearson, Elizabeth K; Bulun, Serdar E

    2012-05-15

    Adulthood weight gain predicts estrogen receptor-positive breast cancer. Because local estrogen excess in the breast likely contributes to cancer development, and aromatase is the key enzyme in estrogen biosynthesis, we investigated the role of local aromatase expression in weight gain-associated breast cancer risk in a humanized aromatase (Arom(hum)) mouse model containing the coding region and the 5'-regulatory region of the human aromatase gene. Compared with littermates on normal chow, female Arom(hum) mice on a high fat diet gained more weight, and had a larger mammary gland mass with elevated total human aromatase mRNA levels via promoters I.4 and II associated with increased levels of their regulators TNFα and C/EBPβ. There was no difference in total human aromatase mRNA levels in gonadal white adipose tissue. Our data suggest that diet-induced weight gain preferentially stimulates local aromatase expression in the breast, which may lead to local estrogen excess and breast cancer risk.

  10. Dynamic energy-balance model predicting gestational weight gain

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gestational weight gains (GWGs) that exceed the 2009 Institute of Medicine recommended ranges increase risk of long-term postpartum weight retention; conversely, GWGs within the recommended ranges are more likely to result in positive maternal and fetal outcomes. Despite this evidence, recent epide...

  11. 24 CFR 3280.507 - Comfort heat gain.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Thermal Protection § 3280.507 Comfort heat... 24 Housing and Urban Development 5 2011-04-01 2011-04-01 false Comfort heat gain. 3280.507 Section 3280.507 Housing and Urban Development Regulations Relating to Housing and Urban Development...

  12. 24 CFR 3280.507 - Comfort heat gain.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Thermal Protection § 3280.507 Comfort heat... 24 Housing and Urban Development 5 2013-04-01 2013-04-01 false Comfort heat gain. 3280.507 Section 3280.507 Housing and Urban Development Regulations Relating to Housing and Urban Development...

  13. 24 CFR 3280.507 - Comfort heat gain.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Thermal Protection § 3280.507 Comfort heat... 24 Housing and Urban Development 5 2012-04-01 2012-04-01 false Comfort heat gain. 3280.507 Section 3280.507 Housing and Urban Development Regulations Relating to Housing and Urban Development...

  14. 24 CFR 3280.507 - Comfort heat gain.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Thermal Protection § 3280.507 Comfort heat... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Comfort heat gain. 3280.507 Section 3280.507 Housing and Urban Development Regulations Relating to Housing and Urban Development...

  15. 24 CFR 3280.507 - Comfort heat gain.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Thermal Protection § 3280.507 Comfort heat... 24 Housing and Urban Development 5 2014-04-01 2014-04-01 false Comfort heat gain. 3280.507 Section 3280.507 Housing and Urban Development Regulations Relating to Housing and Urban Development...

  16. Characterization of newly gained introns in Daphnia populations.

    PubMed

    Li, Wenli; Kuzoff, Robert; Wong, Chen Khuan; Tucker, Abraham; Lynch, Michael

    2014-08-14

    As one of the few known species in an active phase of intron proliferation, the microcrustacean Daphnia pulex is an especially attractive system for interrogating the gain and loss of introns in natural populations. In this study, we used a comparative population-genomic approach to identify and characterize 90 recently gained introns in this species. Molecular clock analyses indicate that these introns arose between 3.9 × 10(5) and 1.45 × 10(4) years ago, with a spike in intron proliferation approximately 5.2 × 10(4) to 1.22 × 10(5) years ago. Parallel gains at homologous positions contribute to 47.8% (43/90) of discovered new introns. A disproportionally large number of new introns were found in historically isolated populations in Oregon. Nonetheless, derived, intron-bearing alleles were also identified in a wide range of geographic locations, suggesting intron gain and, to a lesser degree, intron loss are important sources of genetic variation in natural populations of Daphnia. A majority (55/90 or 61.1%) of the identified neointrons have associated internal direct repeats with lengths and compositions that are unlikely to occur by chance, suggesting repeated bouts of staggered double-strand breaks (DSBs) during their evolution. Accordingly, internal, staggered DSBs may contribute to a passive trend toward increased length and sequence diversity in nascent introns.

  17. Essential oils increase weight gain in channel catfish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We examined the effects of matrix encapsulated essential oils (Biomin® P.E.P. MGE) on weight gain, specific growth rate (SGR), feed conversion ratio (FCR), and survival of channel catfish. Five hundred catfish (32.4 ± 1.7 g/fish) were randomly assigned to two treatments with five replicate tanks/tre...

  18. Does semantic redundancy gain result from multiple semantic priming?

    PubMed

    Schröter, Hannes; Bratzke, Daniel; Fiedler, Anja; Birngruber, Teresa

    2015-10-01

    Fiedler, Schröter, and Ulrich (2013) reported faster responses to a single written word when the semantic content of this word (e.g., "elephant") matched both targets (e.g., "animal", "gray") as compared to a single target (e.g., "animal", "brown"). This semantic redundancy gain was explained by statistical facilitation due to a race of independent memory retrieval processes. The present experiment addresses one alternative explanation, namely that semantic redundancy gain results from multiple pre-activation of words that match both targets. In different blocks of trials, participants performed a redundant-targets task and a lexical decision task. The targets of the redundant-targets task served as primes in the lexical decision task. Replicating the findings of Fiedler et al., a semantic redundancy gain was observed in the redundant-targets task. Crucially, however, there was no evidence of a multiple semantic priming effect in the lexical decision task. This result suggests that semantic redundancy gain cannot be explained by multiple pre-activation of words that match both targets.

  19. A gain-control theory of binocular combination.

    PubMed

    Ding, Jian; Sperling, George

    2006-01-24

    In binocular combination, light images on the two retinas are combined to form a single "cyclopean" perceptual image, in contrast to binocular rivalry which occurs when the two eyes have incompatible ("rivalrous") inputs and only one eye;s stimulus is perceived. We propose a computational theory for binocular combination with two basic principles of interaction: in every spatial neighborhood, each eye (i) exerts gain control on the other eye's signal in proportion to the contrast energy of its own input and (ii) additionally exerts gain control on the other eye's gain control. For stimuli of ordinary contrast, when either eye is stimulated alone, the predicted cyclopean image is the same as when both eyes are stimulated equally, coinciding with an easily observed property of natural vision. The gain-control theory is contrast dependent: Very low-contrast stimuli to the left- and right-eye add linearly to form the predicted cyclopean image. The intrinsic nonlinearity manifests itself only as contrast increases. To test the theory more precisely, a horizontal sine wave grating of 0.68 cycles per degree is presented to each eye. The gratings differ in contrast and phase. The predicted (and perceived) cyclopean grating also is a sine wave; its apparent phase indicates the relative contribution of the two eyes to the cyclopean image. For 48 measured combinations of phase and contrast, the theory with only one estimated parameter accounts for 95% of the variance of the data. Therefore, a simple, robust, physiologically plausible gain-control theory accurately describes an early stage of binocular combination.

  20. Balanced crossmodal excitation and inhibition essential for maximizing multisensory gain.

    PubMed

    Hoshino, Osamu

    2014-07-01

    We examined whether and how the balancing of crossmodal excitation and inhibition affects intersensory facilitation. A neural network model, comprising lower-order unimodal networks (X, Y) and a higher-order multimodal network (M), was simulated. Crossmodal excitation was made by direct activation of principal cells of the X network by the Y network. Crossmodal inhibition was made in an indirect manner: the Y network activated glial cells of the X network. This let glial plasma membrane transporters export GABA molecules into the extracellular space and increased the level of ambient GABA. The ambient GABA molecules were accepted by extrasynaptic GABAa receptors and tonically inhibited principal cells of the X network. Namely, crossmodal inhibition was made through GABAergic gliotransmission. Intersensory facilitation was assessed in terms of multisensory gain: the difference between the numbers of spikes evoked by multisensory (XY) stimulation and unisensory (X-alone) stimulation. The maximal multisensory gain (XY-X) could be achieved at an intermediate noise level by balancing crossmodal excitation and inhibition. This result supports an experimentally derived conclusion: intersensory facilitation under noisy environmental conditions is not necessarily in accord with the principle of inverse effectiveness; rather, multisensory gain is maximal at intermediate signal-to-noise ratio (SNR) levels. The maximal multisensory gain was available at the weakest signal if noise was not present, indicating that the principle of inverse effectiveness is a special case of the intersensory facilitation model proposed here. We suggest that the balancing of crossmodal excitation and inhibition may be crucial for intersensory facilitation. The GABAergic glio-transmission-mediated crossmodal inhibitory mechanism effectively works for intersensory facilitation and on determining the maximal multisensory gain in the entire SNR range between the two extremes: low and high SNRs.

  1. 26 CFR 1.61-6 - Gains derived from dealings in property.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 2 2010-04-01 2010-04-01 false Gains derived from dealings in property. 1.61-6... Taxable Income § 1.61-6 Gains derived from dealings in property. (a) In general. Gain realized on the sale..., relating to capital gains and losses, certain gains derived from dealings in property are treated...

  2. 26 CFR 1.367(a)-8 - Gain recognition agreement requirements.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... filing Form 8838 “Consent to Extend the Time to Assess Tax Under Section 367—Gain Recognition Agreement... time of the gain recognition event; (ii) The amount of gain recognized under the gain recognition... 26 Internal Revenue 4 2010-04-01 2010-04-01 false Gain recognition agreement requirements....

  3. 26 CFR 1.367(a)-8 - Gain recognition agreement requirements.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... filing Form 8838 “Consent to Extend the Time to Assess Tax Under Section 367—Gain Recognition Agreement... time of the gain recognition event; (ii) The amount of gain recognized under the gain recognition... 26 Internal Revenue 4 2012-04-01 2012-04-01 false Gain recognition agreement requirements....

  4. 26 CFR 1.367(a)-8 - Gain recognition agreement requirements.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... filing Form 8838 “Consent to Extend the Time to Assess Tax Under Section 367—Gain Recognition Agreement... time of the gain recognition event; (ii) The amount of gain recognized under the gain recognition... 26 Internal Revenue 4 2011-04-01 2011-04-01 false Gain recognition agreement requirements....

  5. 26 CFR 1.1374-2 - Net recognized built-in gain.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 11 2014-04-01 2014-04-01 false Net recognized built-in gain. 1.1374-2 Section... Net recognized built-in gain. (a) In general. An S corporation's net recognized built-in gain for any... amount by which its net unrealized built-in gain exceeds its net recognized built-in gain for all...

  6. 26 CFR 1.1374-2 - Net recognized built-in gain.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 11 2012-04-01 2012-04-01 false Net recognized built-in gain. 1.1374-2 Section... Net recognized built-in gain. (a) In general. An S corporation's net recognized built-in gain for any... amount by which its net unrealized built-in gain exceeds its net recognized built-in gain for all...

  7. From the Lab Bench: Do you manage pastures for maximum gain per animal or gain per acre?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An article was written to discuss managing cattle pastures to maximize either weight gain or milk output per acre or per animal. There is no or little change in output per animal over a certain range of light stocking rates that allows pasture growth to be greater than forage intake, and increasing...

  8. No pain, no gain: pain behaviour in the armed forces.

    PubMed

    Harper, Phil

    Pain is a unique phenomenon that is difficult to express and is influenced by many different factors, including cultural expectations. A dichotomy exists within the British Armed Forces between pain being seen as necessary--the "no pain, no gain" view--and the opposite image of stoical service personnel who suppress their emotions--the "roughie-toughie" image. This dichotomy was explored through an ethnographic study of pain behaviour experienced during a training course. Pain behaviour was found to be consistent with cultural expectations and this supported the "no pain, no gain" perspective. Physical and psychological pain were expressed differently, reinforcing the western, scientific mind-body dichotomy. In addition, personnel frequently tried to suppress their pain and this supported the "roughie-toughie" philosophy. Thus, pain expression varies according to the context in which it occurs. Nurses need to be aware of this to ensure they interpret and manage their patients' pain appropriately.

  9. Application of gain scheduling to the control of batch bioreactors

    NASA Technical Reports Server (NTRS)

    Cardello, Ralph; San, Ka-Yiu

    1987-01-01

    The implementation of control algorithms to batch bioreactors is often complicated by the inherent variations in process dynamics during the course of fermentation. Such a wide operating range may render the performance of fixed gain PID controllers unsatisfactory. In this work, a detailed study on the control of batch fermentation is performed. Furthermore, a simple batch controller design is proposed which incorporates the concept of gain-scheduling, a subclass of adaptive control, with oxygen uptake rate as an auxiliary variable. The control of oxygen tension in the biorector is used as a vehicle to convey the proposed idea, analysis and results. Simulation experiments indicate significant improvement in controller performance can be achieved by the proposed approach even in the presence of measurement noise.

  10. Sound pressure level gain in an acoustic metamaterial cavity.

    PubMed

    Song, Kyungjun; Kim, Kiwon; Hur, Shin; Kwak, Jun-Hyuk; Park, Jihyun; Yoon, Jong Rak; Kim, Jedo

    2014-12-11

    The inherent attenuation of a homogeneous viscous medium limits radiation propagation, thereby restricting the use of many high-frequency acoustic devices to only short-range applications. Here, we design and experimentally demonstrate an acoustic metamaterial localization cavity which is used for sound pressure level (SPL) gain using double coiled up space like structures thereby increasing the range of detection. This unique behavior occurs within a subwavelength cavity that is 1/10(th) of the wavelength of the incident acoustic wave, which provides up to a 13 dB SPL gain. We show that the amplification results from the Fabry-Perot resonance of the cavity, which has a simultaneously high effective refractive index and effective impedance. We also experimentally verify the SPL amplification in an underwater environment at higher frequencies using a sample with an identical unit cell size. The versatile scalability of the design shows promising applications in many areas, especially in acoustic imaging and underwater communication.

  11. Stability in high gain plasmas in DIII-D

    SciTech Connect

    Lazarus, E.A.; Houlberg, W.A.; Murakami, M.; Wade, M.R.

    1996-10-01

    Fusion power gain has been increased by a factor of 3 in DIII-D plasmas through the use of strong discharge shaping and tailoring of the pressure and current density profiles. H-mode plasmas with weak or negative central magnetic shear are found to have neoclassical ion confinement throughout most of the plasma volume. Improved MHD stability is achieved by controlling the plasma pressure profile width. The highest fusion power gain Q (ratio of fusion power to input power) in deuterium plasmas was 0.0015, which extrapolates to an equivalent Q of 0.32 in a deuterium-tritium plasma and is similar to values achieved in tokamaks of larger size and magnetic fields.

  12. Stability in High Gain Plasmas in DIII-D

    SciTech Connect

    Lazarus, E. A.; Hong, R. M.; Navratil, G. A.; Sabbagh, S.; Strait, E. J.; Rice, B. W.; Ferron, J. R.; Greenfield, C. M.; Austin, M. E.; Chan, V. S.; DeBoo, J. C.; Doyle, E. J.; Forest, C. B.; Leonard, A. W.; Schissel, D. P.; Whyte, D. G.

    1997-01-01

    Fusion power gain has been increased by a factor of 3 in DIII-D plasmas through the use of strong discharge shaping and tailoring of the pressure and current density profiles. H-mode plasmas with weak or negative central magnetic shear are found to have neoclassical ion confinement throughout most of the plasma volume. Improved MHD stability is achieved by controlling the plasma pressure profile width. The highest fusion power gain Q (ratio of fusion power to input power) in deuterium plasmas was 0.0015. which extrapolates to an equivalent Q of 0.32 in a deuterium-tritium plasma and is similar to values achieved in tokamaks of larger size and magnetic fields.

  13. Sound Pressure Level Gain in an Acoustic Metamaterial Cavity

    NASA Astrophysics Data System (ADS)

    Song, Kyungjun; Kim, Kiwon; Hur, Shin; Kwak, Jun-Hyuk; Park, Jihyun; Yoon, Jong Rak; Kim, Jedo

    2014-12-01

    The inherent attenuation of a homogeneous viscous medium limits radiation propagation, thereby restricting the use of many high-frequency acoustic devices to only short-range applications. Here, we design and experimentally demonstrate an acoustic metamaterial localization cavity which is used for sound pressure level (SPL) gain using double coiled up space like structures thereby increasing the range of detection. This unique behavior occurs within a subwavelength cavity that is 1/10th of the wavelength of the incident acoustic wave, which provides up to a 13 dB SPL gain. We show that the amplification results from the Fabry-Perot resonance of the cavity, which has a simultaneously high effective refractive index and effective impedance. We also experimentally verify the SPL amplification in an underwater environment at higher frequencies using a sample with an identical unit cell size. The versatile scalability of the design shows promising applications in many areas, especially in acoustic imaging and underwater communication.

  14. Gain modulation by graphene plasmons in aperiodic lattice lasers

    NASA Astrophysics Data System (ADS)

    Chakraborty, S.; Marshall, O. P.; Folland, T. G.; Kim, Y.-J.; Grigorenko, A. N.; Novoselov, K. S.

    2016-01-01

    Two-dimensional graphene plasmon-based technologies will enable the development of fast, compact, and inexpensive active photonic elements because, unlike plasmons in other materials, graphene plasmons can be tuned via the doping level. Such tuning is harnessed within terahertz quantum cascade lasers to reversibly alter their emission. This is achieved in two key steps: first, by exciting graphene plasmons within an aperiodic lattice laser and, second, by engineering photon lifetimes, linking graphene’s Fermi energy with the round-trip gain. Modal gain and hence laser spectra are highly sensitive to the doping of an integrated, electrically controllable, graphene layer. Demonstration of the integrated graphene plasmon laser principle lays the foundation for a new generation of active, programmable plasmonic metamaterials with major implications across photonics, material sciences, and nanotechnology.

  15. Gain enhancement with near-zero-index metamaterial superstrate

    NASA Astrophysics Data System (ADS)

    Bouzouad, M.; Chaker, S. M.; Bensafielddine, D.; Laamari, E. M.

    2015-11-01

    The objective of this paper was to use a near-zero-index ( n) metamaterial as a single- or a double-layer superstrate suspended above a microstrip patch antenna, operating at 43 GHz, for the gain enhancement. The single metamaterial layer superstrate consists of a periodic arrangement of Jerusalem cross unit cells and behaves as an homogeneous medium characterized by a refractive index close to zero. This metamaterial property allows gathering radiated waves from the antenna and collimates them toward the superstrate normal direction. The proposed design improves the antenna gain by 5.1 dB with the single-layer superstrate and 7 dB with the double-layer superstrate.

  16. Stability of constant gain systems with vector feedback

    NASA Technical Reports Server (NTRS)

    Vonpragenau, G. L.

    1978-01-01

    The state space, the controllability, and the observability concepts are discussed in connection with the proposed stability analysis which permits drastic dimensional reductions for a vector feedback problem. Any constant gain system's stability can thus be analyzed in the frequency domain with a single Nyquist plot. The analysis considers the total system with all loops closed, a disturbance vector as input, and the feedback vector as output. All constant gain systems are shown to be decomposable into stable subsystems where the degree of the decomposition determines the dimensions. The maximum decomposition results in the state-space approach which is the limit case. The method is demonstrated with the stability analysis of the pogo phenomenon, an oscillatory interaction between the propulsion and the structure of a space vehicle. This problem, with eigenvalues over a hundred, was drastically but rigorously reduced to a stability analysis of a 4x4 matrix.

  17. High-Frequency Power Gain in the Mammalian Cochlea

    NASA Astrophysics Data System (ADS)

    Maoiléidigh, Dáibhid Ó.; Hudspeth, A. J.

    2011-11-01

    Amplification in the mammalian inner ear is thought to result from a nonlinear active process known as the cochlear amplifier. Although there is much evidence that outer hair cells (OHCs) play a central role in the cochlear amplifier, the mechanism of amplification remains uncertain. In non-mammalian ears hair bundles can perform mechanical work and account for the active process in vitro, yet in the mammalian cochlea membrane-based electromotility is required for amplification in vivo. A key issue is how OHCs conduct mechanical power amplification at high frequencies. We present a physical model of a segment of the mammalian cochlea that can amplify the power of external signals. In this representation both electromotility and active hair-bundle motility are required for mechanical power gain at high frequencies. We demonstrate how the endocochlear potential, the OHC resting potential, Ca2+ gradients, and ATP-fueled myosin motors serve as the energy sources underlying mechanical power gain in the cochlear amplifier.

  18. Opportunities for biodiversity gains under the world's largest reforestation programme

    PubMed Central

    Hua, Fangyuan; Wang, Xiaoyang; Zheng, Xinlei; Fisher, Brendan; Wang, Lin; Zhu, Jianguo; Tang, Ya; Yu, Douglas W.; Wilcove, David S.

    2016-01-01

    Reforestation is a critical means of addressing the environmental and social problems of deforestation. China's Grain-for-Green Program (GFGP) is the world's largest reforestation scheme. Here we provide the first nationwide assessment of the tree composition of GFGP forests and the first combined ecological and economic study aimed at understanding GFGP's biodiversity implications. Across China, GFGP forests are overwhelmingly monocultures or compositionally simple mixed forests. Focusing on birds and bees in Sichuan Province, we find that GFGP reforestation results in modest gains (via mixed forest) and losses (via monocultures) of bird diversity, along with major losses of bee diversity. Moreover, all current modes of GFGP reforestation fall short of restoring biodiversity to levels approximating native forests. However, even within existing modes of reforestation, GFGP can achieve greater biodiversity gains by promoting mixed forests over monocultures; doing so is unlikely to entail major opportunity costs or pose unforeseen economic risks to households. PMID:27598524

  19. Crystal oscillators using negative voltage gain, single pole response amplifiers

    NASA Technical Reports Server (NTRS)

    Kleinberg, Leonard L. (Inventor)

    1989-01-01

    A simple and inexpensive crystal oscillator is provided which employs negative voltage gain, single pole response amplifiers. The amplifiers may include such configurations as gate inverters, operational amplifiers and conventional bipolar transistor amplifiers, all of which operate at a frequency which is on the roll-off portion of their gain versus frequency curve. Several amplifier feedback circuit variations are employed to set desired bias levels and to allow the oscillator to operate at the crystal's fundamental frequency or at an overtone of the fundamental frequency. The oscillator is made less expensive than comparable oscillators by employing relatively low frequency amplifiers and operating them at roll-off, at frequencies beyond which they are customarily used. Simplicity is provided because operation at roll-off eliminates components ordinarily required in similar circuits to provide sufficient phase-shift in the feedback circuitry for oscillation to occur.

  20. Cathode driven high gain crossed-field amplifier

    NASA Astrophysics Data System (ADS)

    1983-07-01

    The objective of this three-phase program is to achieve the design of a cathode driven high gain re-entrant Crossed Field Amplifier capable of meeting the parameters of Raytheon Company specification No. 968838 dated 10 May 1978. The effort includes the fabrication and test of three developmental and four final configuration tubes. One final configuration tube will be life tested and two will be delivered to the Navy. The tasks discussed during this report period relate to the cold tests performed on various subassemblies of model no. 4 and on the sealed-in model no. 4 of the S-band high gain cathode driven crossed field amplifier. Based on the performance of model no. 3 certain remedial measures have been implemented in model no. 4 that have resulted in the elimination of key resonances within the tube and an improvement in the isolation between the cathode and anode circuits.

  1. Fixed gain and adaptive techniques for rotorcraft vibration control

    NASA Technical Reports Server (NTRS)

    Roy, R. H.; Saberi, H. A.; Walker, R. A.

    1985-01-01

    The results of an analysis effort performed to demonstrate the feasibility of employing approximate dynamical models and frequency shaped cost functional control law desgin techniques for helicopter vibration suppression are presented. Both fixed gain and adaptive control designs based on linear second order dynamical models were implemented in a detailed Rotor Systems Research Aircraft (RSRA) simulation to validate these active vibration suppression control laws. Approximate models of fuselage flexibility were included in the RSRA simulation in order to more accurately characterize the structural dynamics. The results for both the fixed gain and adaptive approaches are promising and provide a foundation for pursuing further validation in more extensive simulation studies and in wind tunnel and/or flight tests.

  2. Application of small-signal fusion energy gain

    SciTech Connect

    Jassby, D.L.

    1986-11-01

    The measured burnup fraction of the 1-MeV tritons produced in a deuterium tokamak plasma, multiplied by 17.5, is essentially the small-signal fusion energy gain g/sub T/ for an ideal 1-MeV triton beam injected into the deuterium plasma. The measured g/sub T/ can be converted directly into the two-component fusion energy gain that would be realized if a lower energy tritium beam were injected into the plasma, or if a deuterium beam were injected into a tritium target plasma having the same parameters as the acutal deuterium plasma. Under certain conditions, g/sub T/ greater than or equal to 1 can be obtained by injection of a low-current 225-keV tritium beam into a hot deuterium plasma, thereby verifying that the plasma has the essential characteristics needed for achieving macroscopic fusion energy ''break-even.''

  3. Gain control in molecular information processing: lessons from neuroscience

    NASA Astrophysics Data System (ADS)

    Nemenman, Ilya

    2012-04-01

    Statistical properties of environments experienced by biological signaling systems in the real world change, which necessitates adaptive responses to achieve high fidelity information transmission. One form of such adaptive response is gain control. Here, we argue that a certain simple mechanism of gain control, understood well in the context of systems neuroscience, also works for molecular signaling. The mechanism allows us to transmit more than 1 bit (on or off) of information about the signal independent of the signal variance. It does not require additional molecular circuitry beyond that already present in many molecular systems, and in particular, it does not depend on existence of feedback loops. The mechanism provides a potential explanation for abundance of ultrasensitive response curves in biological regulatory networks.

  4. Antenna gain measurements in the intermediate-field zone

    NASA Astrophysics Data System (ADS)

    Anchidin, Liliana; Bari, Farida; Dumitrascu, Ana; Paun, Mirel; Deacu, Daniela; Tasu, Sorin; Danisor, Alin; Tamas, Razvan D.

    2016-12-01

    Antenna gain is usually evaluated under far-field conditions. Furthermore, Friis transmission formula can solely be applied when antenna size can be neglected with respect to the distance between the measuring antenna and the antenna under test. In this paper, we show that by applying the distance averaging technique the far-field and antenna size constraints can be overcome. Our method was validated by measuring a monopole antenna and a Vivaldi antenna in an open area test site (OATS).

  5. Counterintuitive dispersion violating Kramers-Kronig relations in gain slabs.

    PubMed

    Wang, Li-Gang; Wang, Lin; Al-Amri, M; Zhu, Shi-Yao; Zubairy, M Suhail

    2014-06-13

    We demonstrate the counterintuitive dispersion effect that the peaks (dips) in the gain spectrum correspond to abnormal (normal) dispersion, contrary to the usual Kramers-Kronig point of view. This effect may also lead to two unique features: a broadband abnormal dispersion region and an observable Hartman effect. These results are explained in terms of interference and boundary effects. Finally, two experiments are proposed for the potential experimental verification.

  6. Silicon photodiodes with high photoconductive gain at room temperature.

    PubMed

    Li, X; Carey, J E; Sickler, J W; Pralle, M U; Palsule, C; Vineis, C J

    2012-02-27

    Silicon photodiodes with high photoconductive gain are demonstrated. The photodiodes are fabricated in a complementary metal-oxide-semiconductor (CMOS)-compatible process. The typical room temperature responsivity at 940 nm is >20 A/W and the dark current density is ≈ 100 nA/cm2 at 5 V reverse bias, yielding a detectivity of ≈ 10(14) Jones. These photodiodes are good candidates for applications that require high detection sensitivity and low bias operation.

  7. High Efficiency Targets for High Gain Inertial Confinement Fusion.

    DTIC Science & Technology

    1986-09-19

    Inertial Confinement Fusion JOHN H. GARDNER AND STEPHEN E. BODNER Laboratory for Computational Physics DTIC CD ELECTEf OCT 241986 j NU Aproedfr...81425 " 11 TITLE (include Security Classification) High Efficiency Targets for High Gain Inertial Confinement Fusion 12. PERSONAL AUTHOR(S) Gardner, John ...ArearCod) 22c OFFICE SYMBOL % John H. Gardner (202) 767-3055 Code 4040 DO FORM 1473. 84 MAR 83 APR edtion may be used until exhausted SECURITY

  8. Gestational weight gain and medical outcomes of pregnancy

    PubMed Central

    Ferraro, Zachary M; Contador, Fernanda; Tawfiq, Afaf; Adamo, Kristi B

    2015-01-01

    This narrative review discusses gestational weight gain (GWG) and medical outcomes of pregnancy, including metabolic, cardiovascular, respiratory, musculoskeletal and psychiatric systems. Taken as a whole, the available evidence shows that excessive GWG increases the risk of all medical complications of pregnancy, and negatively impacts the long-term health and weight of both mothers and their offspring. Briefly, interventions to encourage appropriate GWG are discussed and readers are directed to resources to facilitate discussion of pregnancy weight. PMID:27512468

  9. Remote Robot Control With High Force-Feedback Gain

    NASA Technical Reports Server (NTRS)

    Kim, Won S.

    1993-01-01

    Improved scheme for force-reflecting hand control of remote robotic manipulator provides unprecedently high force-reflection gain, even when dissimilar master and slave arms used. Three feedback loops contained in remote robot control system exerting position-error-based force feedback and compliance control. Outputs of force and torque sensors on robot not used directly for force reflection, but for compliance control, while errors in position used to generate reflected forces.

  10. Soft Drinks and Weight Gain: How Strong Is the Link?

    PubMed Central

    Wolff, Emily; Dansinger, Michael L.

    2008-01-01

    Context Soft drink consumption in the United States has tripled in recent decades, paralleling the dramatic increases in obesity prevalence. The purpose of this clinical review is to evaluate the extent to which current scientific evidence supports a causal link between sugar-sweetened soft drink consumption and weight gain. Evidence acquisition MEDLINE search of articles published in all languages between 1966 and December 2006 containing key words or medical subheadings, such as “soft drinks” and “weight.” Additional articles were obtained by reviewing references of retrieved articles, including a recent systematic review. All reports with cross-sectional, prospective cohort, or clinical trial data in humans were considered. Evidence synthesis Six of 15 cross-sectional and 6 of 10 prospective cohort studies identified statistically significant associations between soft drink consumption and increased body weight. There were 5 clinical trials; the two that involved adolescents indicated that efforts to reduce sugar-sweetened soft drinks slowed weight gain. In adults, 3 small experimental studies suggested that consumption of sugar-sweetened soft drinks caused weight gain; however, no trial in adults was longer than 10 weeks or included more than 41 participants. No trial reported the effects on lipids. Conclusions Although observational studies support the hypothesis that sugar-sweetened soft drinks cause weight gain, a paucity of hypothesis-confirming clinical trial data has left the issue open to debate. Given the magnitude of the public health concern, larger and longer intervention trials should be considered to clarify the specific effects of sugar-sweetened soft drinks on body weight and other cardiovascular risk factors. PMID:18924641

  11. Change in Neighborhood Socioeconomic Status and Weight Gain

    PubMed Central

    Powell-Wiley, Tiffany M.; Cooper-McCann, Rebecca; Ayers, Colby; Berrigan, David; Lian, Min; McClurkin, Michael; Barbash, Rachel Ballard; Das, Sandeep R.; Hoehner, Christine M.; Leonard, Tammy

    2015-01-01

    Introduction Despite a proposed connection between neighborhood environment and obesity, few longitudinal studies have examined the relationship between change in neighborhood socioeconomic deprivation, as defined by moving between neighborhoods, and change in body weight. The purpose of this study is to examine the longitudinal relationship between moving to more socioeconomically deprived neighborhoods and weight gain as a cardiovascular risk factor. Methods Weight (kg) was measured in the Dallas Heart Study (DHS), a multiethnic cohort aged 18–65 years, at baseline (2000–2002) and 7-year follow-up (2007–2009, N=1,835). Data were analyzed in 2013–2014. Geocoded addresses were linked to Dallas County, TX census block groups. A block group-level neighborhood deprivation index (NDI) was created. Multilevel difference-in-difference models with random effects and a Heckman correction factor (HCF) determined weight change relative to NDI change. Results Forty-nine percent of the DHS population moved (263 to higher NDI, 586 to lower NDI, 47 within same NDI), with blacks more likely to move than whites or Hispanics (p<0.01), but similar baseline BMI and waist circumference were observed in movers vs. non-movers (p>0.05). Adjusting for HCF, sex, race, and time-varying covariates, those who moved to areas of higher NDI gained more weight compared to those remaining in the same or moving to a lower NDI (0.64 kg per 1-unit NDI increase, 95% CI=0.09, 1.19). Impact of NDI change on weight gain increased with time (p=0.03). Conclusions Moving to more–socioeconomically deprived neighborhoods was associated with weight gain among DHS participants. PMID:25960394

  12. Design issues for a laboratory high gain fusion facility

    SciTech Connect

    Hogan, W.J.

    1987-11-02

    In an inertial fusion laboratory high gain facility, experiments will be carried out with up to 1000 MJ of thermonuclear yield. The experiment area of such a facility will include many systems and structures that will have to operate successfully in the difficult environment created by the sudden large energy release. This paper estimates many of the nuclear effects that will occur, discusses the implied design issues and suggests possible solutions so that a useful experimental facility can be built. 4 figs.

  13. Gain, Level, And Exposure Control For A Television Camera

    NASA Technical Reports Server (NTRS)

    Major, Geoffrey J.; Hetherington, Rolfe W.

    1992-01-01

    Automatic-level-control/automatic-gain-control (ALC/AGC) system for charge-coupled-device (CCD) color television camera prevents over-loading in bright scenes using technique for measuring brightness of scene from red, green, and blue output signals and processing these into adjustments of video amplifiers and iris on camera lens. System faster, does not distort video brightness signals, and built with smaller components.

  14. High gain preamplifier based on optical parametric amplification

    DOEpatents

    Jovanovic, Igor; Bonner, Randal A.

    2004-08-10

    A high-gain preamplifier based on optical parametric amplification. A first nonlinear crystal is operatively connected to a second nonlinear crystal. A first beam relay telescope is operatively connected to a second beam relay telescope, to the first nonlinear crystal, and to the second nonlinear crystal. A first harmonic beamsplitter is operatively connected to a second harmonic beamsplitter, to the first nonlinear crystal, to the second nonlinear crystal, to the first beam relay telescope, and to the second beam relay telescope.

  15. Christian Learner: Wisdom and Gaining Knowledge Equals Joy

    ERIC Educational Resources Information Center

    Nagle, Bonne

    2012-01-01

    When a Christian learner gains insight that learning is needed and takes the appropriate action to learn the knowledge and apply it, there will be joy and satisfaction with learning. The premise for this paper is in the Bible verse Ecclesiastes 2:26: (NASB) "For to a person who is good in His sight He has given wisdom and knowledge and joy..."…

  16. Accumulated distribution of material gain at dislocation crystal growth

    NASA Astrophysics Data System (ADS)

    Rakin, V. I.

    2016-05-01

    A model for slowing down the tangential growth rate of an elementary step at dislocation crystal growth is proposed based on the exponential law of impurity particle distribution over adsorption energy. It is established that the statistical distribution of material gain on structurally equivalent faces obeys the Erlang law. The Erlang distribution is proposed to be used to calculate the occurrence rates of morphological combinatorial types of polyhedra, presenting real simple crystallographic forms.

  17. Travel distance and mass gain in wintering blackbirds.

    PubMed

    Cresswell

    1999-11-01

    Birds that range over a large area will have a greater mass-dependent risk of predation than more sedentary birds. Birds that travel more may then reduce winter mass gain to compensate for the increased predation risk that greater travelling entails. I tested whether European blackbirds, Turdus merula, that travelled more in winter had a lower mass than more sedentary birds, independently of any confounding effects of food supply on both ranging behaviour and mass gain. I measured change in winter mass and amount of food eaten in conjunction with the distance that blackbirds travelled to a randomly sited mobile feeder. Blackbirds that travelled shorter distances (per trip and in total) and less often to the feeder had the highest mass midwinter relative to their spring mass. Blackbirds with a higher mean mass midwinter also travelled, on average, shorter distances to the feeder. The distance an individual blackbird travelled to the feeder at any one time was probably independent of the state of its daily energy reserves (how much of its daily total mass gain it had achieved at that point). The relationship between distance travelled and mass was probably independent of food supply because distances actually increased at the end of the winter and the amount of food eaten per individual changed little. More mobile blackbirds were therefore likely to have compensated for any increases in predation risk associated with their greater ranges by decreasing winter mass gain, but will have had an increased risk of starvation because of their lower mass. Copyright 1999 The Association for the Study of Animal Behaviour.

  18. Approach to interior design for passive direct gain solar homes

    SciTech Connect

    Kachadorian, C.C.

    1980-01-01

    In response to requests from buyers and builders of direct gain passive solar homes interior design criteria either specific to, or emphasized by, passive solar buildings are investigated. Problems of high sunlight penetration, secondary illumination, material selection, sound control and psychology are approached. Material deterioration, fading, glare, noise, and a sense of spacial confinement can be minimized, contributing to the appeal and saleability of passive solar homes.

  19. Development of a 233 GHz High Gain Traveling Wave Amplifier

    DTIC Science & Technology

    2014-04-22

    USA 2Beam Wave Research, Inc., Bethesda, MD 20814 USA Abstract: We present development plans for a 233 GHz, serpentine waveguide vacuum electron...NRL G-band serpentine waveguide amplifier [2, 3] was the first demonstrated amplifier to use a UV-LIGA fabricated circuit. The small- signal gain...using the same techniques for 231.5 GHz to 235 GHz, an FCC Radiolocation band. Amplifier Design The compound, hybrid serpentine waveguide (SWG

  20. Hygroscopic weight gain of pollen grains from Juniperus species

    NASA Astrophysics Data System (ADS)

    Bunderson, Landon D.; Levetin, Estelle

    2015-05-01

    Juniperus pollen is highly allergenic and is produced in large quantities across Texas, Oklahoma, and New Mexico. The pollen negatively affects human populations adjacent to the trees, and since it can be transported hundreds of kilometers by the wind, it also affects people who are far from the source. Predicting and tracking long-distance transport of pollen is difficult and complex. One parameter that has been understudied is the hygroscopic weight gain of pollen. It is believed that juniper pollen gains weight as humidity increases which could affect settling rate of pollen and thus affect pollen transport. This study was undertaken to examine how changes in relative humidity affect pollen weight, diameter, and settling rate. Juniperus ashei, Juniperus monosperma, and Juniperus pinchotii pollen were applied to greased microscope slides and placed in incubation chambers under a range of temperature and humidity levels. Pollen on slides were weighed using an analytical balance at 2- and 6-h intervals. The size of the pollen was also measured in order to calculate settling rate using Stokes' Law. All pollen types gained weight as humidity increased. The greatest settling rate increase was exhibited by J. pinchotii which increased by 24 %.

  1. Hygroscopic weight gain of pollen grains from Juniperus species.

    PubMed

    Bunderson, Landon D; Levetin, Estelle

    2015-05-01

    Juniperus pollen is highly allergenic and is produced in large quantities across Texas, Oklahoma, and New Mexico. The pollen negatively affects human populations adjacent to the trees, and since it can be transported hundreds of kilometers by the wind, it also affects people who are far from the source. Predicting and tracking long-distance transport of pollen is difficult and complex. One parameter that has been understudied is the hygroscopic weight gain of pollen. It is believed that juniper pollen gains weight as humidity increases which could affect settling rate of pollen and thus affect pollen transport. This study was undertaken to examine how changes in relative humidity affect pollen weight, diameter, and settling rate. Juniperus ashei, Juniperus monosperma, and Juniperus pinchotii pollen were applied to greased microscope slides and placed in incubation chambers under a range of temperature and humidity levels. Pollen on slides were weighed using an analytical balance at 2- and 6-h intervals. The size of the pollen was also measured in order to calculate settling rate using Stokes' Law. All pollen types gained weight as humidity increased. The greatest settling rate increase was exhibited by J. pinchotii which increased by 24 %.

  2. Robust Gaussian teleportation with attenuation and nonunity gain

    NASA Astrophysics Data System (ADS)

    de Faria, Alencar J.

    2016-12-01

    The average fidelity of the teleportation of coherent states is calculated for general Gaussian bipartite systems shared by the partners of the protocol, Alice and Bob. It is considered that the shared Gaussian bipartite modes suffer independent attenuations before the processing of Alice and Bob. In addition, the classical communication between the partners can be controlled by a gain not necessarily unitary. Comparing with the classical fidelity threshold of measure-and-prepare methods, we establish several genuinely quantum teleportation conditions which depend on the gain and the local attenuations. If the gain can be tuned to maximize the bipartite state set capable of performing genuinely quantum teleportation, then a condition for teleportation robust against local attenuations is found. This condition is demonstrated to be essentially equivalent to the condition of robust Gaussian bipartite entanglement, obtained in previous articles, showing that the robustness against attenuations is an entanglement property relevant for characterization and application of bipartite systems. For the derivation of the robust teleportation conditions, the Gaussian operations onto the bipartite system are thoroughly studied, so that the transformations that maintain the fidelity invariant are found. Some scenarios for different Gaussian bipartite states are presented and discussed.

  3. Noise Induces Biased Estimation of the Correction Gain

    PubMed Central

    Ahn, Jooeun; Zhang, Zhaoran; Sternad, Dagmar

    2016-01-01

    The detection of an error in the motor output and the correction in the next movement are critical components of any form of motor learning. Accordingly, a variety of iterative learning models have assumed that a fraction of the error is adjusted in the next trial. This critical fraction, the correction gain, learning rate, or feedback gain, has been frequently estimated via least-square regression of the obtained data set. Such data contain not only the inevitable noise from motor execution, but also noise from measurement. It is generally assumed that this noise averages out with large data sets and does not affect the parameter estimation. This study demonstrates that this is not the case and that in the presence of noise the conventional estimate of the correction gain has a significant bias, even with the simplest model. Furthermore, this bias does not decrease with increasing length of the data set. This study reveals this limitation of current system identification methods and proposes a new method that overcomes this limitation. We derive an analytical form of the bias from a simple regression method (Yule-Walker) and develop an improved identification method. This bias is discussed as one of other examples for how the dynamics of noise can introduce significant distortions in data analysis. PMID:27463809

  4. The Effect of Ranitidine on Olanzapine-Induced Weight Gain

    PubMed Central

    Ranjbar, Fatemeh; Ghanepour, Alireza; Asadlo, Mahbob; Alizadeh, Amineh

    2013-01-01

    Induced weight gain is a disturbing side effect of Olanzapine that affects the quality of life in psychotic patients. The aim of this study was to assess the efficacy of Ranitidine in attenuating or preventing Olanzapine-induced weight gain. A parallel 2-arm clinical trial was done on 52 patients with schizophrenia, schizoaffective and schizophreniform disorders who received Olanzapine for the first time. All these were first-episode admitted patients. They were randomly allocated to receive either Ranitidine or placebo. The trend of body mass index (BMI) was compared between groups over 16-week course of treatment. Mean weight was 62.3 (SD: 9.6) kg at baseline. Thirty-three subjects (63.5%) had positive family history of obesity. The average BMI increment was 1.1 for Ranitidine group and 2.4 for the placebo group. The multivariate analysis showed this effect to be independent of sex, family history of obesity, and baseline BMI value. The longitudinal modeling after controlling for baseline values failed to show the whole trend slope to be different. Although the slight change in trend's slope puts forward a hypothesis that combined use of Ranitidine and Olanzapine may attenuate the weight gain long run, this needs to be retested in future larger scale long-term studies. This trial is registered with IRCT.ir 201009112181N5. PMID:23984393

  5. Prospective associations of eating behaviors with weight gain in infants

    PubMed Central

    Shepard, Desti N.; Chandler-Laney, Paula C.

    2015-01-01

    Objective To examine whether maternal reports of infant eating behaviors are stable over time and whether eating behaviors are prospectively associated with weight gain. Methods In an ongoing study of infant growth, weight and length were measured at 2-weeks, 3-months, and 5-months of age. Food responsiveness (FR), satiety responsiveness (SR), enjoyment of feeding (EF), and slow eating (SE) were assessed with the Baby Eating Behavior Questionnaire. Repeated measures ANOVA were used to examine changes in eating behaviors from 2-weeks to 5-months. Simple Pearson correlations examined associations among eating behaviors across time, and associations of eating behaviors with subsequent change in weight-for-length z-scores. Results Among 31 infants studied from 2-weeks to 3-months, FR and SR remained consistent (P<0.05), and among 21 infants studied from 3- to 5-months, FR, EF, and SE were consistent (P<0.01). Infants ate more quickly (P<0.01), and tended to have greater SR with age (P=0.09). Only SE at 3-months was associated with subsequent gain in weight-for-length (P<0.05). Conclusions Consistent with previous research, SE was predictive of weight gain during infancy. Given that eating behaviors were largely consistent after 3-months of age, it may be important to encourage the development of healthy eating behaviors during early infancy. PMID:26242892

  6. High-Gain High-Field Fusion Plasma

    PubMed Central

    Li, Ge

    2015-01-01

    A Faraday wheel (FW)—an electric generator of constant electrical polarity that produces huge currents—could be implemented in an existing tokamak to study high-gain high-field (HGHF) fusion plasma, such as the Experimental Advanced Superconducting Tokamak (EAST). HGHF plasma can be realized in EAST by updating its pulsed-power system to compress plasma in two steps by induction fields; high gains of the Lawson trinity parameter and fusion power are both predicted by formulating the HGHF plasma. Both gain rates are faster than the decrease rate of the plasma volume. The formulation is checked by earlier ATC tests. Good agreement between theory and tests indicates that scaling to over 10 T at EAST may be possible by two-step compressions with a compression ratio of the minor radius of up to 3. These results point to a quick new path of fusion plasma study, i.e., simulating the Sun by EAST. PMID:26507314

  7. Optical gain in single tensile-strained germanium photonic wire.

    PubMed

    de Kersauson, M; El Kurdi, M; David, S; Checoury, X; Fishman, G; Sauvage, S; Jakomin, R; Beaudoin, G; Sagnes, I; Boucaud, P

    2011-09-12

    We have investigated the optical properties of tensile-strained germanium photonic wires. The photonic wires patterned by electron beam lithography (50 μm long, 1 μm wide and 500 nm thick) are obtained by growing a n-doped germanium film on a GaAs substrate. Tensile strain is transferred in the germanium layer using a Si₃N₄ stressor. Tensile strain around 0.4% achieved by the technique corresponds to an optical recombination of tensile-strained germanium involving light hole band around 1690 nm at room temperature. We show that the waveguided emission associated with a single tensile-strained germanium wire increases superlinearly as a function of the illuminated length. A 20% decrease of the spectral broadening is observed as the pump intensity is increased. All these features are signatures of optical gain. A 80 cm⁻¹ modal optical gain is derived from the variable strip length method. This value is accounted for by the calculated gain material value using a 30 band k · p formalism. These germanium wires represent potential building blocks for integration of nanoscale optical sources on silicon.

  8. Automatic gain control. [the Loran-C receiver

    NASA Technical Reports Server (NTRS)

    Roman, J. P.

    1981-01-01

    An automatic gain control (AGC), designed to operate with the prototype Loran-C receiver, is described. The device is used to eliminate error which occurs when signals are received at different magnitudes. The automatic gain control is a three transistor circuit which requires a constant dc voltage of 8 volts. Tests conclude that this value may be in the range of 4 to 12 v without change in circuit performance. Two transistors are cascaded to pass and amplify the input signal. Their gain is controlled by a third transistor which itself is controlled by an external AGC voltage between 0 and 8 volts dc. The integrated circuit used is an 8 pin chip, which is a differential cascade amplifier designed for use in communications operating at frequencies from dc to 120 MHz. The integrated circuit was balanced for AGC capabilities, and has a wide operating current range. The maximum input current at pins 1 and 5 is 0.1 mAmps. AGC testing is described.

  9. Measurement of reverberation gain in an urban environment.

    PubMed

    Mijić, Miomir; Šumarac Pavlović, Dragana

    2012-09-01

    Multipath propagation within an urban area introduces a specific type of reverberation in response to sound excitation. That appearance affects the level of ambient noise produced by strong sound sources. In this paper, the signals recorded during the 1999 bombing of Belgrade were used to analyze the characteristics of reverberation in that urban environment. Six recorded signals were selected among more than 50 explosions recorded at that time. Due to the impulse nature of sound sources, the recorded signals represent the impulse responses of that area. The measured reverberation time T30 is about 7 ± 1 s in octaves between 31.5 Hz and 1 kHz. There is a variation of decay slope in time that is verified by differences between values of T10 and T30. The reverberation gain calculated from recorded signals is 2-7 dB, depending on the global position of the sound excitation point as well as its micro-location according to its position among the surrounding buildings. A variation of gain over octave bands is in the interval of approximately 3 dB. Information about reverberation gain in urban environment can be useful in a quick estimation of noise level produced by strong sound sources in a large area of urban environment.

  10. Competence with fractions predicts gains in mathematics achievement.

    PubMed

    Bailey, Drew H; Hoard, Mary K; Nugent, Lara; Geary, David C

    2012-11-01

    Competence with fractions predicts later mathematics achievement, but the codevelopmental pattern between fractions knowledge and mathematics achievement is not well understood. We assessed this codevelopment through examination of the cross-lagged relation between a measure of conceptual knowledge of fractions and mathematics achievement in sixth and seventh grades (N=212). The cross-lagged effects indicated that performance on the sixth grade fractions concepts measure predicted 1-year gains in mathematics achievement (ß=.14, p<.01), controlling for the central executive component of working memory and intelligence, but sixth grade mathematics achievement did not predict gains on the fractions concepts measure (ß=.03, p>.50). In a follow-up assessment, we demonstrated that measures of fluency with computational fractions significantly predicted seventh grade mathematics achievement above and beyond the influence of fluency in computational whole number arithmetic, performance on number fluency and number line tasks, central executive span, and intelligence. Results provide empirical support for the hypothesis that competence with fractions underlies, in part, subsequent gains in mathematics achievement.

  11. Monitoring the WFC3/UVIS Relative Gain with Internal Flatfields

    NASA Astrophysics Data System (ADS)

    Fowler, J.; Baggett, S.

    2017-03-01

    The WFC3/UVIS gain stability has been monitored twice yearly. This project provides a new examination of gain stability, making use of the existing internal flatfield observations taken every three days (for the Bowtie monitor) for a regular look at relative gain stability. Amplifiers are examined for consistency both in comparison to each other and over time, by normalizing the B, C, and D amplifiers to A, and then plotting statistics for each of the three normalized amplifiers with time. We find minimal trends in these statistics, with a 0.02 - 0.2% change in mean amplifier ratio over 7.5 years. The trends in the amplifiers are well-behaved with the exception of the B/A ratio, which shows increased scatter in mean, median, and standard deviation. The cause of the scatter remains unclear though we find it is not dependent upon detector defects, filter features, or shutter effects, and is only observable after pixel flagging (both from the data quality arrays and outlier values) has been applied.

  12. Stacked Transformer for Driver Gain and Receive Signal Splitting

    NASA Technical Reports Server (NTRS)

    Driscoll, Kevin R.

    2013-01-01

    In a high-speed signal transmission system that uses transformer coupling, there is a need to provide increased transmitted signal strength without adding active components. This invention uses additional transformers to achieve the needed gain. The prior art uses stronger drivers (which require an IC redesign and a higher power supply voltage), or the addition of another active component (which can decrease reliability, increase power consumption, reduce the beneficial effect of serializer/deserializer preemphasis or deemphasis, and/or interfere with fault containment mechanisms), or uses a different transformer winding ratio (which requires redesign of the transformer and may not be feasible with high-speed signals that require a 1:1 winding ratio). This invention achieves the required gain by connecting the secondaries of multiple transformers in series. The primaries of these transformers are currently either connected in parallel or are connected to multiple drivers. There is also a need to split a receive signal to multiple destinations with minimal signal loss. Additional transformers can achieve the split. The prior art uses impedance-matching series resistors that cause a loss of signal. Instead of causing a loss, most instantiations of this invention would actually provide gain. Multiple transformers are used instead of multiple windings on a single transformer because multiple windings on the same transformer would require a redesign of the transformer, and may not be feasible with high-speed transformers that usually require a bifilar winding with a 1:1 ratio. This invention creates the split by connecting the primaries of multiple transformers in series. The secondary of each transformer is connected to one of the intended destinations without the use of impedance-matching series resistors.

  13. Loss/gain on ignition testing for HC-21C

    SciTech Connect

    De Vries, M.L.

    1994-12-12

    The HC-21C thermal stabilization process stabilizes reactive plutonium bearing material for long term storage. A Loss On Ignition (LOI) analysis is performed on all materials that are stabilized in the muffle furnaces prior to being stored in the vaults to ensure suitability for vault storage. The material is required to have a LOI of less than 1% (OSD-184-00013 Limit). The LOI analysis is performed to assure that all volatiles that could potentially pressurize the sealed containers over long periods of time, like water, have been removed. It is possible, while performing LOI analysis to see a Gain On Ignition (GOI) due to additional oxidation of materials. In the current stabilization campaign, two items processed have had a positive LOI or GOI result. One concern with a GOI is that the weight gain may actually be masking a weight loss. (Reference 15530-94-WSL-156). Other concerns with a GOI result are that the removal of the oxygen could create a vacuum in the product can causing it to collapse during long term storage or the oxidation of material would increase the volume of the solids potentially bulging or rupturing the product container. In the past, GOIs have been seen on items that were processed through Hoskin`s pot furnaces located in glovebox HA-21I. This test plan provides instruction to test causes of a GOI and to ensure the processed material with a GOI result will not cause a problem during long term storage. Product cans that are sampled for LOI and have results showing a gain of weight will be the test items.

  14. Germanium photodetector with 60 GHz bandwidth using inductive gain peaking.

    PubMed

    Novack, Ari; Gould, Mike; Yang, Yisu; Xuan, Zhe; Streshinsky, Matthew; Liu, Yang; Capellini, Giovanni; Lim, Andy Eu-Jin; Lo, Guo-Qiang; Baehr-Jones, Tom; Hochberg, Michael

    2013-11-18

    Germanium-on-silicon photodetectors have been heavily investigated in recent years as a key component of CMOS-compatible integrated photonics platforms. It has previously been shown that detector bandwidths could theoretically be greatly increased with the incorporation of a carefully chosen inductor and capacitor in the photodetector circuit. Here, we show the experimental results of such a circuit that doubles the detector 3dB bandwidth to 60 GHz. These results suggest that gain peaking is a generally applicable tool for increasing detector bandwidth in practical photonics systems without requiring the difficult process of lowering detector capacitance.

  15. STARS A Two Stage High Gain Harmonic Generation FEL Demonstrator

    SciTech Connect

    M. Abo-Bakr; W. Anders; J. Bahrdt; P. Budz; K.B. Buerkmann-Gehrlein; O. Dressler; H.A. Duerr; V. Duerr; W. Eberhardt; S. Eisebitt; J. Feikes; R. Follath; A. Gaupp; R. Goergen; K. Goldammer; S.C. Hessler; K. Holldack; E. Jaeschke; Thorsten Kamps; S. Klauke; J. Knobloch; O. Kugeler; B.C. Kuske; P. Kuske; A. Meseck; R. Mitzner; R. Mueller; M. Neeb; A. Neumann; K. Ott; D. Pfluckhahn; T. Quast; M. Scheer; Th. Schroeter; M. Schuster; F. Senf; G. Wuestefeld; D. Kramer; Frank Marhauser

    2007-08-01

    BESSY is proposing a demonstration facility, called STARS, for a two-stage high-gain harmonic generation free electron laser (HGHG FEL). STARS is planned for lasing in the wavelength range 40 to 70 nm, requiring a beam energy of 325 MeV. The facility consists of a normal conducting gun, three superconducting TESLA-type acceleration modules modified for CW operation, a single stage bunch compressor and finally a two-stage HGHG cascaded FEL. This paper describes the faciliy layout and the rationale behind the operation parameters.

  16. GAINS AND LOSSES OF COMMINGLED WATERS IN A STREAM.

    USGS Publications Warehouse

    Mac Nish, R.D.

    1985-01-01

    In a legal dispute in the State of Washington (Colville Confederated Tribes vs. Boyd Walton, Jr. , Farmer), it became necessary to determine the proportion of transmission losses sustained by developed water that was commingled with native water in a natural stream channel. Ground-water pumping and irrigation adjacent to the stream resulted in both gains and losses to flow along the study reach. The identification of the native and developed waters was accomplished by a detailed study of the reach that combined current-meter measurements with an analysis of the dilution of an injected brine.

  17. Around-the-World Atomic Clocks: Predicted Relativistic Time Gains.

    PubMed

    Hafele, J C; Keating, R E

    1972-07-14

    During October 1971, four cesium beam atomic clocks were flown on regularly scheduled commercial jet flights around the world twice, once eastward and once westward, to test Einstein's theory of relativity with macroscopic clocks. From the actual flight paths of each trip, the theory predicts that the flying clocks, compared with reference clocks at the U.S. Naval Observatory, should have lost 40 +/- 23 nanoseconds during the eastward trip, and should have gained 275 +/- 21 nanoseconds during the westward trip. The observed time differences are presented in the report that follows this one.

  18. A high gain antenna system for airborne satellite communication applications

    NASA Technical Reports Server (NTRS)

    Maritan, M.; Borgford, M.

    1990-01-01

    A high gain antenna for commercial aviation satellites communication is discussed. Electromagnetic and practical design considerations as well as candidate systems implementation are presented. An evaluation of these implementation schemes is given, resulting in the selection of a simple top mounted aerodynamic phased array antenna with a remotely located beam steering unit. This concept has been developed into a popular product known as the Canadian Marconi Company CMA-2100. A description of the technical details is followed by a summary of results from the first production antennas.

  19. FEL Gain Length and Taper Measurements at LCLS

    SciTech Connect

    Ratner, Daniel; Brachmann, A.; Decker, F.J.; Ding, Y.; Dowell, D.; Emma, P.; Frisch, J.; Gilevich, S.; Hays, G.; Hering, P.; Huang, Z.; Iverson, R.; Loos, H.; Miahnahri, A.; Nuhn, H.D.; Turner, J.; Welch, J.; White, W.; Wu, J.; Xiang, D.; Yocky, G.; /SLAC /LBL, Berkeley

    2010-07-30

    We present experimental studies of the gain length and saturation power level from 1.5 nm to 1.5 {angstrom} at the Linac Coherent Light Source (LCLS). By disrupting the FEL process with an orbit kick, we are able to measure the X-ray intensity as a function of undulator length. This kick method is cross-checked with the method of removing undulator sections. We also study the FEL-induced electron energy loss after saturation to determine the optimal taper of the undulator K values. The experimental results are compared to theory and simulations.

  20. A high gain microstrip array adopting EMC dipoles

    NASA Astrophysics Data System (ADS)

    Russo, P.; Ruggieri, M.

    1988-10-01

    The design and operation of microstrip antenna arrays based on commercial feed boards and electromagnetically coupled (EMC) dipoles are described and illustrated with extensive drawings, graphs, and diagrams. The analysis of the radiating element and feeder network is outlined, and a 4 x 1 H-plane array and a 4 x 4 array operating at 11.7-12.5 GHz in linear or circular polarization are characterized in detail. With uniform illumination the latter array had directivity 21.75-22.08 db, gain 20.85-21.27 dB, voltage/standing-wave ratio 1.35-1.55:1, and efficiency 79-85 percent.

  1. Gain and loss of esteem, direct reciprocity and Heider balance

    NASA Astrophysics Data System (ADS)

    Hassanibesheli, Forough; Hedayatifar, Leila; Gawroński, Przemysław; Stojkow, Maria; Żuchowska-Skiba, Dorota; Kułakowski, Krzysztof

    2017-02-01

    The effect of gain and loss of esteem is introduced into the equations of time evolution of social relations, hostile or friendly, in a group of actors. The equations allow for asymmetric relations. We prove that in the presence of this asymmetry, the majority of stable solutions are jammed states, i.e. the Heider balance is not attained there. A phase diagram is constructed with three phases: the jammed phase, the balanced phase with two mutually hostile groups, and the phase of so-called paradise, where all relations are friendly.

  2. Accounting For Gains And Orientations In Polarimetric SAR

    NASA Technical Reports Server (NTRS)

    Freeman, Anthony

    1992-01-01

    Calibration method accounts for characteristics of real radar equipment invalidating standard 2 X 2 complex-amplitude R (receiving) and T (transmitting) matrices. Overall gain in each combination of transmitting and receiving channels assumed different even when only one transmitter and one receiver used. One characterizes departure of polarimetric Synthetic Aperture Radar (SAR) system from simple 2 X 2 model in terms of single parameter used to transform measurements into format compatible with simple 2 X 2 model. Data processed by applicable one of several prior methods based on simple model.

  3. Wireless Sensor Networks: Some Insights Gained in West African Hydrology

    NASA Astrophysics Data System (ADS)

    Parlange, M. B.; Mande, T.; Ceperley, N. C.; Katul, G. G.; Van De Giesen, N.; Tyler, S. W.

    2015-12-01

    We present recent observations gained through a robust wireless sensor network deployed in Burkina Faso in the southeastern Savanna over a five year period. The impact of land surface and cover change due to agricultural expansion are discussed relative to precipitation patterns. It is shown that the impact on forest and land clearing results in reduced surface heat fluxes and reduction in convective rainfall. In addition, the pattern of ground water recharge is controlled by water viscosity changes due to diurnal heating in ephemeral streams and the sensors allowed further exploration of the shallow ground water system.

  4. X ray laser with enhanced x ray gain through photodepopulation

    NASA Astrophysics Data System (ADS)

    Elton, Raymond C.

    1990-07-01

    This patent discloses a nuclear charge Z lasing on a 3-2 Balmer-a transition, a second hydrogenic ion having a nuclear charge Z/2 emitting Lyman-a and Lyman-B photons, wherein n=2 electrons of he first hydrogenic ion are excited to the n=4 and n=6 level by resonance absorption of Lyman-a and Lyman-B photons from the second hydrogenic ion. The invention results in an increase in population inversion and gain to saturation, an improvement in overall efficiency and an increase in plasma size.

  5. Simultaneous gain and phase profile determination on an interferometric BOTDA

    NASA Astrophysics Data System (ADS)

    Angulo-Vinuesa, X.; Lopez-Gil, A.; Dominguez-López, A.; Cruz, J. L.; Andres, M. V.; Martin-Lopez, S.; Gonzalez-Herraez, M.

    2015-09-01

    Up to now, complex (phase and intensity) measurements in Brillouin Optical Time-Domain Analysis (BOTDA) systems required complex phase modulation methods and high-bandwidth (multi-GHz) detection. In this work, we propose a novel technique that is able to retrieve simultaneously both gain/loss and phase characteristics of the Brillouin interaction by just introducing a Sagnac Interferometer (SI) on a standard BOTDA sensing scheme. The technique is described analytically and demonstrated experimentally. With this technique, a reliability increase is produced since redundant measurements can be performed.

  6. Gain, noise, and contrast sensitivity of linear visual neurons

    NASA Technical Reports Server (NTRS)

    Watson, Andrew B.

    1990-01-01

    Contrast sensitivity is a measure of the ability of an observer to detect contrast signals of particular spatial and temporal frequencies. A formal definition of contrast sensitivity that can be applied to individual linear visual neurons is derived. A neuron is modeled by a contrast transfer function and its modulus, contrast gain, and by a noise power spectrum. The distributions of neural responses to signal and blank presentations are derived, and from these, a definition of contrast sensitivity is obtained. This formal definition may be used to relate the sensitivities of various populations of neurons, and to relate the sensitivities of neurons to that of the behaving animal.

  7. 26 CFR 1.58-8 - Capital gains and stock options.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... derived by a company on the sale of fixed assets held for less than 2 years are treated as short-term gains. The excess of short-term gains in any fiscal year is taxed at the full company tax rate of 50... realization of such short-term gains. Since recognition of the short-term gains for tax purposes is subject...

  8. 26 CFR 1.58-8 - Capital gains and stock options.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... derived by a company on the sale of fixed assets held for less than 2 years are treated as short-term gains. The excess of short-term gains in any fiscal year is taxed at the full company tax rate of 50... realization of such short-term gains. Since recognition of the short-term gains for tax purposes is subject...

  9. 26 CFR 1.731-1 - Extent of recognition of gain or loss on distribution.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... recognition of gain or loss on distribution. (a) Recognition of gain or loss to partner—(1) Recognition of gain. (i) Where money is distributed by a partnership to a partner, no gain shall be recognized to the partner except to the extent that the amount of money distributed exceeds the adjusted basis of...

  10. 26 CFR 1.731-1 - Extent of recognition of gain or loss on distribution.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... of recognition of gain or loss on distribution. (a) Recognition of gain or loss to partner—(1) Recognition of gain. (i) Where money is distributed by a partnership to a partner, no gain shall be recognized to the partner except to the extent that the amount of money distributed exceeds the adjusted...

  11. 26 CFR 1.1374-2 - Net recognized built-in gain.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 11 2013-04-01 2013-04-01 false Net recognized built-in gain. 1.1374-2 Section... Net recognized built-in gain. (a) In general. An S corporation's net recognized built-in gain for any... corporations and considering only its recognized built-in gain, recognized built-in loss, and recognized...

  12. 26 CFR 1.367(a)-8 - Gain recognition agreement requirements.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... of gain subject to the gain recognition agreement at the time of the gain recognition event; (ii) The... 26 Internal Revenue 4 2013-04-01 2013-04-01 false Gain recognition agreement requirements. 1.367(a... recognition agreement requirements. (a) Scope. This section provides the terms and conditions for a...

  13. 26 CFR 1.367(a)-8 - Gain recognition agreement requirements.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... of gain subject to the gain recognition agreement at the time of the gain recognition event; (ii) The... 26 Internal Revenue 4 2014-04-01 2014-04-01 false Gain recognition agreement requirements. 1.367(a... recognition agreement requirements. (a) Scope. This section provides the terms and conditions for a...

  14. 26 CFR 1.1374-2 - Net recognized built-in gain.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 11 2011-04-01 2011-04-01 false Net recognized built-in gain. 1.1374-2 Section... Net recognized built-in gain. (a) In general. An S corporation's net recognized built-in gain for any... corporations and considering only its recognized built-in gain, recognized built-in loss, and recognized...

  15. Research on gain uniformity of the laser non-imaging rod amplifier

    NASA Astrophysics Data System (ADS)

    Wu, Yongzhong; Zhu, Jianqiang

    2015-08-01

    According to the problem of gain medium cross section high illumination and non-uniformity, which is caused by the laser rod amplifier non-imaging pump style. Orthogonal test design method is used to research the effect of absorption coefficient, gain medium radius, number of xenon lamps, center distance of xenon lamps and gain medium on gain uniformity. The rod amplifier which is made up by the above four elements, its gain medium cross section illumination distribution is simulated by ASAP. The results show that center distance of xenon lamps and gain medium, number of xenon lamps have very little influence on the gain uniformity. When absorption coefficient equal to 5.1 cm-1, gain uniformity will reach the optimum. Under the circumstance of other three elements are equal, the bigger is the gain radius, the smaller slope reflection curve, and the better gain uniformity.

  16. Ribose Accelerates Gut Motility and Suppresses Mouse Body Weight Gaining

    PubMed Central

    Liu, Yan; Li, Tong-Ruei R; Xu, Cong; Xu, Tian

    2016-01-01

    The increasing prevalence of obesity is closely related to excessive energy consumption. Clinical intervention of energy intake is an attractive strategy to fight obesity. However, the current FDA-approved weight-loss drugs all have significant side effects. Here we show that ribose upregulates gut motility and suppresses mice body weight gain. Ribokinase, which is encoded by Rbks gene, is the first enzyme for ribose metabolism in vivo. Rbks mutation resulted in ribose accumulation in the small intestine, which accelerated gut movement. Ribose oral treatment in wild type mice also enhanced bowel motility and rendered mice resistance to high fat diets. The suppressed weight gain was resulted from enhanced ingested food excretion. In addition, the effective dose of ribose didn't cause any known side effects (i.e. diarrhea and hypoglycemia). Overall, our results show that ribose can regulate gut motility and energy homeostasis in mice, and suggest that administration of ribose and its analogs could regulate gastrointestinal motility, providing a novel therapeutic approach for gastrointestinal dysfunction and weight control. PMID:27194947

  17. Depth from motion parallax scales with eye movement gain.

    PubMed

    Nawrot, Mark

    2003-12-18

    Recent findings suggest that the slow eye movement system, the optokinetic response (OKR) in particular, provides the extra-retinal signal required for the perception of depth from motion parallax (Nawrot, 2003). Considering that both the perception of depth from motion parallax (Ono, Rivest & Ono, 1986; Rivest, Ono & Saida, 1989) and the eye movements made in response to head translations (Schwarz & Miles 1991; Paige, Telford, Seidmen, & Barnes, 1998) appear to scale with viewing distance, changes in perceived depth from motion parallax were studied as a function of viewing distance. If OKR is used in the perception of depth from motion parallax, a change in the OKR signal, caused by a change in viewing distance, should accompany a change in perceived depth from motion parallax. Over a range of viewing distances, binocular stereopsis was used to index perceived depth from motion parallax. At these viewing distances the gain of the OKR portion of the compensatory eye movement was also determined. The results show that the change in OKR gain is mirrored by the change in perceived depth from motion parallax as viewing distance increases. This suggests that the OKR eye movement signal serves an important function in the perception of depth from motion.

  18. Transient-gain photoionization x-ray laser

    NASA Astrophysics Data System (ADS)

    Weninger, Clemens; Rohringer, Nina

    2014-12-01

    We present a generalized theory based on one-dimensional Maxwell-Bloch equations to study the amplification process of an inner-shell photoionization-pumped atomic x-ray laser. Focusing an x-ray free-electron laser beam in an elongated neon-gas target results in a strong exponential amplification of K α fluorescence, as recently demonstrated [N. Rohringer et al., Nature (London) 481, 488 (2012), 10.1038/nature10721; C. Weninger et al., Phys. Rev. Lett. 111, 233902 (2013), 10.1103/PhysRevLett.111.233902]. Here, we present an in-depth theoretical study of the amplification process that goes beyond the previous theory based on a rate-equation approach. We study the evolution of the pulse characteristics during the amplification process for transform-limited Gaussian and broadband self-amplified spontaneous-emission pump pulses. We discuss the impact of the gain-dependent group velocity on the emitted x-ray radiation and the resulting gain-guiding effects. A thorough analysis of the spectral and temporal properties of the emitted radiation is presented, including higher-order field-correlation functions, to characterize the ensemble of emitted x-ray pulses.

  19. Mass Gains of the Antarctic Ice Sheet Exceed Losses

    NASA Technical Reports Server (NTRS)

    Zwally, H. Jay; Li, Jun; Robbins, John; Saba, Jack L.; Yi, Donghui; Brenner, Anita; Bromwich, David

    2012-01-01

    During 2003 to 2008, the mass gain of the Antarctic ice sheet from snow accumulation exceeded the mass loss from ice discharge by 49 Gt/yr (2.5% of input), as derived from ICESat laser measurements of elevation change. The net gain (86 Gt/yr) over the West Antarctic (WA) and East Antarctic ice sheets (WA and EA) is essentially unchanged from revised results for 1992 to 2001 from ERS radar altimetry. Imbalances in individual drainage systems (DS) are large (-68% to +103% of input), as are temporal changes (-39% to +44%). The recent 90 Gt/yr loss from three DS (Pine Island, Thwaites-Smith, and Marie-Bryd Coast) of WA exceeds the earlier 61 Gt/yr loss, consistent with reports of accelerating ice flow and dynamic thinning. Similarly, the recent 24 Gt/yr loss from three DS in the Antarctic Peninsula (AP) is consistent with glacier accelerations following breakup of the Larsen B and other ice shelves. In contrast, net increases in the five other DS of WA and AP and three of the 16 DS in East Antarctica (EA) exceed the increased losses. Alternate interpretations of the mass changes driven by accumulation variations are given using results from atmospheric-model re-analysis and a parameterization based on 5% change in accumulation per degree of observed surface temperature change. A slow increase in snowfall with climate waRMing, consistent with model predictions, may be offsetting increased dynamic losses.

  20. Gantry cranes gain scheduling feedback control with friction compensation

    NASA Astrophysics Data System (ADS)

    Omar, Hanafy M.; Nayfeh, Ali H.

    2005-03-01

    We designed a controller based on gain-scheduling feedback to move a load on a gantry crane from point to point within one oscillation cycle and without inducing large swings. The settling time of the system is taken to be equal to the period of oscillation of the load. This criterion enables calculation of the controller feedback gains for varying load weight and cable length. Numerical simulations show that the controller is effective in reducing load oscillations and transferring the load in a reasonable time compared with that of optimal control. To experimentally validate the theory, we had to compensate for friction. To this end, we estimated the friction, and then applied an opposite control action to cancel it. To estimate the friction force, we assumed a mathematical model, and then we estimated the model coefficients using an off-line identification technique, such as the method of least squares (LS). First, the process of identification is applied to a theoretical model of a DC motor with known friction coefficients. From this example, some guidelines and rules are deduced for the choice of the LS parameters. Then, the friction coefficients of the gantry crane model are estimated and validated.

  1. Consensus+Innovations Distributed Kalman Filter With Optimized Gains

    NASA Astrophysics Data System (ADS)

    Das, Subhro; Moura, Jose M. F.

    2017-01-01

    In this paper, we address the distributed filtering and prediction of time-varying random fields represented by linear time-invariant (LTI) dynamical systems. The field is observed by a sparsely connected network of agents/sensors collaborating among themselves. We develop a Kalman filter type consensus+innovations distributed linear estimator of the dynamic field termed as Consensus+Innovations Kalman Filter. We analyze the convergence properties of this distributed estimator. We prove that the mean-squared error of the estimator asymptotically converges if the degree of instability of the field dynamics is within a pre-specified threshold defined as tracking capacity of the estimator. The tracking capacity is a function of the local observation models and the agent communication network. We design the optimal consensus and innovation gain matrices yielding distributed estimates with minimized mean-squared error. Through numerical evaluations, we show that, the distributed estimator with optimal gains converges faster and with approximately 3dB better mean-squared error performance than previous distributed estimators.

  2. Radio interferometric gain calibration as a complex optimization problem

    NASA Astrophysics Data System (ADS)

    Smirnov, O. M.; Tasse, C.

    2015-05-01

    Recent developments in optimization theory have extended some traditional algorithms for least-squares optimization of real-valued functions (Gauss-Newton, Levenberg-Marquardt, etc.) into the domain of complex functions of a complex variable. This employs a formalism called the Wirtinger derivative, and derives a full-complex Jacobian counterpart to the conventional real Jacobian. We apply these developments to the problem of radio interferometric gain calibration, and show how the general complex Jacobian formalism, when combined with conventional optimization approaches, yields a whole new family of calibration algorithms, including those for the polarized and direction-dependent gain regime. We further extend the Wirtinger calculus to an operator-based matrix calculus for describing the polarized calibration regime. Using approximate matrix inversion results in computationally efficient implementations; we show that some recently proposed calibration algorithms such as STEFCAL and peeling can be understood as special cases of this, and place them in the context of the general formalism. Finally, we present an implementation and some applied results of COHJONES, another specialized direction-dependent calibration algorithm derived from the formalism.

  3. Fuel gain exceeding unity in an inertially confined fusion implosion.

    PubMed

    Hurricane, O A; Callahan, D A; Casey, D T; Celliers, P M; Cerjan, C; Dewald, E L; Dittrich, T R; Döppner, T; Hinkel, D E; Berzak Hopkins, L F; Kline, J L; Le Pape, S; Ma, T; MacPhee, A G; Milovich, J L; Pak, A; Park, H-S; Patel, P K; Remington, B A; Salmonson, J D; Springer, P T; Tommasini, R

    2014-02-20

    Ignition is needed to make fusion energy a viable alternative energy source, but has yet to be achieved. A key step on the way to ignition is to have the energy generated through fusion reactions in an inertially confined fusion plasma exceed the amount of energy deposited into the deuterium-tritium fusion fuel and hotspot during the implosion process, resulting in a fuel gain greater than unity. Here we report the achievement of fusion fuel gains exceeding unity on the US National Ignition Facility using a 'high-foot' implosion method, which is a manipulation of the laser pulse shape in a way that reduces instability in the implosion. These experiments show an order-of-magnitude improvement in yield performance over past deuterium-tritium implosion experiments. We also see a significant contribution to the yield from α-particle self-heating and evidence for the 'bootstrapping' required to accelerate the deuterium-tritium fusion burn to eventually 'run away' and ignite.

  4. Dendritic Excitability and Gain Control in Recurrent Cortical Microcircuits

    PubMed Central

    Hay, Etay; Segev, Idan

    2015-01-01

    Layer 5 thick tufted pyramidal cells (TTCs) in the neocortex are particularly electrically complex, owing to their highly excitable dendrites. The interplay between dendritic nonlinearities and recurrent cortical microcircuit activity in shaping network response is largely unknown. We simulated detailed conductance-based models of TTCs forming recurrent microcircuits that were interconnected as found experimentally; the network was embedded in a realistic background synaptic activity. TTCs microcircuits significantly amplified brief thalamocortical inputs; this cortical gain was mediated by back-propagation activated N-methyl-d-aspartate depolarizations and dendritic back-propagation-activated Ca2+ spike firing, ignited by the coincidence of thalamic-activated somatic spike and local dendritic synaptic inputs, originating from the cortical microcircuit. Surprisingly, dendritic nonlinearities in TTCs microcircuits linearly multiplied thalamic inputs—amplifying them while maintaining input selectivity. Our findings indicate that dendritic nonlinearities are pivotal in controlling the gain and the computational functions of TTCs microcircuits, which serve as a dominant output source for the neocortex. PMID:25205662

  5. Alcohol gains access to appetitive learning through adolescent heavy drinking.

    PubMed

    DiLeo, Alyssa; Wright, Kristina M; Mangone, Elizabeth; McDannald, Michael A

    2015-08-01

    Adolescent heavy alcohol drinking increases the risk for alcohol use disorders in adulthood, yet mechanisms conferring increased risk are not well understood. We propose that adolescent alcohol drinking shapes alcohol's aversive or appetitive properties in adulthood. Alcohol normally drives aversive learning and alcohol-predictive cues are avoided. We hypothesize that through adolescent heavy drinking alcohol gains access to appetitive learning. A primary consequence is that alcohol-predictive cues become valued and sought out. To test this hypothesis, we gave genetically heterogeneous, male Long Evans rats voluntary, chronic intermittent access to water or alcohol throughout adolescence and then identified moderate and heavy alcohol drinkers. After a short abstinence period, we assessed the aversive or appetitive properties of alcohol using flavor learning procedures. We compared alcohol to the known appetitive properties of sugar. Flavor learning in adult rats who were alcohol-naïve or adolescent moderate alcohol drinkers revealed alcohol to be aversive and sugar to be appetitive. The same flavor learning procedures revealed both alcohol and sugar to be appetitive in adult rats who were adolescent heavy drinkers. The results demonstrate that alcohol gains access to neurobehavioral circuits for appetitive learning through adolescent heavy alcohol drinking.

  6. A Presynaptic Gain Control Mechanism Fine-Tunes Olfactory Behavior

    PubMed Central

    Root, Cory M.; Masuyama, Kaoru; Green, David S.; Enell, Lina E.; Nässel, Dick R.; Lee, Chi-Hon; Wang, Jing W.

    2008-01-01

    Early sensory processing can play a critical role in sensing environmental cues. We have investigated the physiological and behavioral function of gain control at the first synapse of olfactory processing in Drosophila. We report that olfactory receptor neurons (ORNs) express the GABAB receptor (GABABR) and its expression expands the dynamic range of ORN synaptic transmission that is preserved in projection neuron responses. Strikingly, we find that different ORN channels have unique baseline levels of GABABR expression. ORNs that sense the aversive odorant CO2 do not express GABABRs nor exhibit any presynaptic inhibition. In contrast, pheromone-sensing ORNs express a high level of GABABRs and exhibit strong presynaptic inhibition. Furthermore, a behavioral significance of presynaptic inhibition was revealed by a courtship behavior in which pheromone-dependent mate localization is impaired in flies that lack GABABRs in specific ORNs. Together, these findings indicate that different olfactory receptor channels may employ heterogeneous presynaptic gain control as a mechanism to allow an animal’s innate behavioral responses to match its ecological needs. PMID:18667158

  7. A gain-scheduled observer under transmissions without delivery acknowledgment

    NASA Astrophysics Data System (ADS)

    Dolz, Daniel; Peñarrocha, Ignacio; Sanchis, Roberto

    2015-11-01

    This paper addresses the estimation problem for discrete-time systems where both measurements and control commands are sent to a central station through a lossy network without delivery acknowledgment. The central unit implements the estimation and control algorithms. We propose a jump observer that uses the expected value of the unknown control input at the actuator to run an open loop estimation. Then, the absence of acknowledgment in the control input transmission is dealt with through the introduction of an unknown disturbance. The observer update is performed by means of jumping gains when there are available measurements. We employ an statistic of the control error (new disturbance), i.e., the difference between the control inputs at the plant and at the observer, to schedule the observer gains in real time. The observer is designed to minimize the H∞ norm from disturbances, measurement noises and control input errors, to estimation error. The infinite-dimensional design problem is turn into an optimization problem over polynomials using sum-of-squares decomposition techniques. Benefits of the proposal are shown in a simulation example.

  8. Leaf conductance and carbon gain under salt-stressed conditions

    NASA Astrophysics Data System (ADS)

    Volpe, V.; Manzoni, S.; Marani, M.; Katul, G.

    2011-12-01

    Exposure of plants to salt stress is often accompanied by reductions in leaf photosynthesis and in stomatal and mesophyll conductances. To separate the effects of salt stress on these quantities, a model based on the hypothesis that carbon gain is maximized subject to a water loss cost is proposed. The optimization problem of adjusting stomatal aperture for maximizing carbon gain at a given water loss is solved for both a non-linear and a linear biochemical demand function. A key novel theoretical outcome of the optimality hypothesis is an explicit relationship between the stomatal and mesophyll conductances that can be evaluated against published measurements. The approaches here successfully describe gas-exchange measurements reported for olive trees (Olea europea L.) and spinach (Spinacia oleraceaL.) in fresh water and in salt-stressed conditions. Salt stress affected both stomatal and mesophyll conductances and photosynthetic efficiency of both species. The fresh water/salt water comparisons show that the photosynthetic capacity is directly reduced by 30%-40%, indicating that reductions in photosynthetic rates under increased salt stress are not due only to a limitation of CO2diffusion. An increase in salt stress causes an increase in the cost of water parameter (or marginal water use efficiency) exceeding 100%, analogous in magnitude to findings from extreme drought stress studies. The proposed leaf-level approach can be incorporated into physically based models of the soil-plant-atmosphere system to assess how saline conditions and elevated atmospheric CO2 jointly impact transpiration and photosynthesis.

  9. Empathic responses to others' gains and losses: an electrophysiological investigation.

    PubMed

    Ma, Qingguo; Shen, Qiang; Xu, Qing; Li, Diandian; Shu, Liangchao; Weber, Bernd

    2011-02-01

    A growing number of studies in exploring empathic modulation have revealed the neural substrates of how social stimuli are represented in the human brain, especially the pain of others. The empathic response of observing other's gains and losses, however, remains not clearly characterized. In the current study, we carried out two experiments with a gamble task to investigate how the effects of interpersonal familiarity and self-participation work on modulating the temporal neural response towards gain and loss of a friend or a stranger using scalp-recorded event-related potentials (ERPs). The electrophysiological data show an increased amplitude of the P300 when observing a friend's performance compared to strangers playing the game in both two experiments. But the distinction of differentiated feedback-related negativity (d-FRN) between friends and strangers was only observed when the player was not involved in the game. These results indicated that the participants exerted more motivational relevance toward their friends than strangers, but the participants' empathic response toward friends was only salient when they were not involved in the gamble directly. Therefore, both familiarity and self-engagement are factors that influence the empathy towards others, complementing the recent research on empathic modulation.

  10. Gain Modulation by Nicotine in Macaque V1

    PubMed Central

    Disney, Anita A.; Aoki, Chiye; Hawken, Michael J.

    2010-01-01

    SUMMARY Acetylcholine is a ubiquitous cortical neuromodulator implicated in cognition. In order to understand the potential for acetylcholine to play a role in visual attention, we studied nicotinic acetylcholine receptor (nAChR) localization and function in area V1 of the macaque. We found nAChRs presynaptically at thalamic synapses onto excitatory, but not inhibitory, neurons in the primary thalamorecipient layer 4c. Furthermore, consistent with the release enhancement suggested by this localization, we discovered that nicotine increases responsiveness and lowers contrast threshold in layer 4c neurons. We also found that nAChRs are expressed by GABAergic interneurons in V1 but rarely by pyramidal neurons, and that nicotine suppresses visual responses outside layer 4c. All sensory systems incorporate gain control mechanisms, or processes which dynamically alter input/output relationships. We demonstrate that at the site of thalamic input to visual cortex, the effect of this nAChR-mediated gain is an enhancement of the detection of visual stimuli. PMID:18031686

  11. Representational gain in cortical area underlies increase of memory strength.

    PubMed

    Bieszczad, Kasia M; Weinberger, Norman M

    2010-02-23

    Neuronal plasticity that develops in the cortex during learning is assumed to represent memory content, but the functions of such plasticity are actually unknown. The shift in spectral tuning in primary auditory cortex (A1) to the frequency of a tone signal is a compelling candidate for a substrate of memory because it has all of the cardinal attributes of associative memory: associativity, specificity, rapid induction, consolidation, and long-term retention. Tuning shifts increase the representational area of the signal in A1, as an increasing function of performance level, suggesting that area encodes the magnitude of acquired stimulus significance. The present study addresses the question of the specific function of learning-induced associative representational plasticity. We tested the hypothesis that specific increases in A1 representational area for an auditory signal serve the mnemonic function of enhancing memory strength for that signal. Rats were trained to bar-press for reward contingent on the presence of a signal tone (5.0 kHz), and assessed for memory strength during extinction. The amount of representational area gain for the signal frequency band was significantly positively correlated with resistance to extinction to the signal frequency in two studies that spanned the range of task difficulty. These findings indicate that specific gain in cortical representational area underlies the strength of the behaviorally-relevant contents of memory. Thus, mnemonic functions of cortical plasticity are determinable.

  12. A Simplified Model for Detonation Based Pressure-Gain Combustors

    NASA Technical Reports Server (NTRS)

    Paxson, Daniel E.

    2010-01-01

    A time-dependent model is presented which simulates the essential physics of a detonative or otherwise constant volume, pressure-gain combustor for gas turbine applications. The model utilizes simple, global thermodynamic relations to determine an assumed instantaneous and uniform post-combustion state in one of many envisioned tubes comprising the device. A simple, second order, non-upwinding computational fluid dynamic algorithm is then used to compute the (continuous) flowfield properties during the blowdown and refill stages of the periodic cycle which each tube undergoes. The exhausted flow is averaged to provide mixed total pressure and enthalpy which may be used as a cycle performance metric for benefits analysis. The simplicity of the model allows for nearly instantaneous results when implemented on a personal computer. The results compare favorably with higher resolution numerical codes which are more difficult to configure, and more time consuming to operate.

  13. Gain and lasing of optically pumped metastable rare gas atoms.

    PubMed

    Han, Jiande; Heaven, Michael C

    2012-06-01

    Optically pumped alkali vapor lasers are currently being developed in several laboratories. The objective is to construct high-powered lasers that also exhibit excellent beam quality. Considerable progress has been made, but there are technical challenges associated with the reactivity of the metal atoms. Rare gas atoms (Rg) excited to the np(5)(n+1)s (3)P(2) configuration are metastable and have spectral properties that are closely similar to those of the alkali metals. In principle, optically pumped lasers could be constructed using excitation of the np(5)(n+1)p←np(5)(n+1)s transitions. We have demonstrated this potential by observing gain and lasing for optically pumped Ar(*), Kr(*) and Xe(*). Three-level lasing schemes were used, with He or Ar as the collisional energy transfer agent that established the population inversion. These laser systems have the advantage of using inert reagents that are gases at room temperature.

  14. The Gain of Resource Delegation in Distributed Computing Environments

    NASA Astrophysics Data System (ADS)

    Fölling, Alexander; Grimme, Christian; Lepping, Joachim; Papaspyrou, Alexander

    In this paper, we address job scheduling in Distributed Computing Infrastructures, that is a loosely coupled network of autonomous acting High Performance Computing systems. In contrast to the common approach of mutual workload exchange, we consider the more intuitive operator's viewpoint of load-dependent resource reconfiguration. In case of a site's over-utilization, the scheduling system is able to lease resources from other sites to keep up service quality for its local user community. Contrary, the granting of idle resources can increase utilization in times of low local workload and thus ensure higher efficiency. The evaluation considers real workload data and is done with respect to common service quality indicators. For two simple resource exchange policies and three basic setups we show the possible gain of this approach and analyze the dynamics in workload-adaptive reconfiguration behavior.

  15. Casimir forces in multilayer magnetodielectrics with both gain and loss

    SciTech Connect

    Amooghorban, Ehsan; Wubs, Martijn; Mortensen, N. Asger; Kheirandish, Fardin

    2011-07-15

    A path-integral approach to the quantization of the electromagnetic field in a linearly amplifying magnetodielectric medium is presented. Two continua of inverted harmonic oscillators are used to describe the polarizability and magnetizability of the amplifying medium. The causal susceptibilities of the amplifying medium, with negative imaginary parts in finite frequency intervals, are identified and their relationships to microscopic coupling functions are determined. By carefully relating the two-point functions of the field theory to the optical Green functions, we calculate the Casimir energy and Casimir forces for a multilayer magnetodielectric medium with both gain and loss. We point out the essential differences with a purely passive layered medium. For a single layer, we find different bounds on the Casimir force for fully amplifying and for lossy media. The force is attractive in both cases, even if the medium exhibits negative refraction. From our Lagrangian we also derive by canonical quantization the postulates of the phenomenological theory of amplifying magnetodielectrics.

  16. Gain and frequency tuning within the mouse cochlear apex

    NASA Astrophysics Data System (ADS)

    Oghalai, John S.; Gao, Simon; Lee, Hee Yoon; Raphael, Patrick D.; Groves, Andrew K.; Zuo, Jian; Applegate, Brian E.

    2015-12-01

    Normal mammalian hearing requires cochlear outer hair cell active processes that amplify the traveling wave with high gain and sharp tuning, termed cochlear amplification. We have used optical coherence tomography to study cochlear amplification within the apical turn of the mouse cochlea. We measured not only classical basilar membrane vibratory tuning curves but also vibratory responses from the rest of the tissues that compose the organ of Corti. Basilar membrane tuning was sharp in live mice and broad in dead mice, whereas other regions of the organ of Corti demonstrated phase shifts consistent with additional filtering beyond that provided by basilar membrane mechanics. We use these experimental data to support a conceptual framework of how cochlear amplification is tuned within the mouse cochlear apex. We will also study transgenic mice with targeted mutations that affect different biomechanical aspects of the organ of Corti in an effort to localize the underlying processes that produce this additional filtering.

  17. Pseudo-fermions in an Electronic Loss-Gain Circuit

    NASA Astrophysics Data System (ADS)

    Bagarello, F.; Pantano, G.

    2013-12-01

    In some recent papers a loss-gain electronic circuit has been introduced and analyzed within the context of PT-quantum mechanics. In this paper we show that this circuit can be analyzed using the formalism of the so-called pseudo-fermions. In particular we discuss the time behavior of the circuit, and we construct two biorthogonal bases associated to the Liouville matrix used in the treatment of the dynamics. We relate these bases to and , and we also show that a self-adjoint Liouville-like operator could be introduced in the game. Finally, we describe the time evolution of the circuit in an Heisenberg-like representation, driven by a non self-adjoint Hamiltonian.

  18. Background Rates of Gain Amplifying Detectors in Space

    NASA Astrophysics Data System (ADS)

    MacDonald, E.; Avanov, L. A.; Gliese, U.; Pollock, C. J.; Giles, B. L.; Funsten, H. O.; Larsen, B.; Skoug, R. M.; Gershman, D. J.; Barrie, A. C.; Coffey, V. N.; Chandler, M. O.; Mauk, B.; Dorelli, J.; Rager, A. C.

    2015-12-01

    In the near Earth space environment plasma instruments utilize gain multiplying detectors such as microchannel plates (MCPs) or channel electron multipliers (CEMs) to amplify single impacting particles into countable electronic pulses. These detectors also respond to higher energy particles such as penetrating MeV electron and proton radiation. Such background signals can be significant enough to be confused with foreground signals of interest in environments like Earth or Jovian radiation belts. It is thus critically important to fully understand the sensitivity of MCP and CEM detectors in situ. In the lab, MCPs are estimated to be ~ 20 times more sensitive per unit input area than CEMs. We will compare the background rates for two recent instruments, the Helium Oxygen Proton Electron (HOPE) mass spectrometer for the Van Allen Probes, and the Fast Plasma Investigation (FPI) instrument suite on the Magnetospheric Multiscale Mission to their respective penetrating radiation environment and estimate the relative response rates for these two types of detectors.

  19. Development of a pressure gain combustor for improved cycle efficiency

    SciTech Connect

    Gemmen, R.S.; Richards, G.A.; Janus, M.C.

    1994-09-01

    This paper presents results from an experimental research program attempting to improve the thermodynamic efficiencies of gas-turbine combustors. An elementary thermodynamic analysis shows that the thermodynamic cycle efficiencies of gas turbines can be significantly improved by using unsteady combustion that achieves quasi-constant-volume combustion. The ability to produce the so-called pressure gain via this process has already been demonstrated by others for pressures less than 3 atmospheres. This paper presents experimental results for pressures up to 11 atmospheres, compares certain process parameters to a numerical simulation, and briefly examines the problem of scale-up. Results of pollutant measurements over the 2--11 atmospheric range of operation are also included.

  20. Software reconfigurable highly flexible gain switched optical frequency comb source.

    PubMed

    Pascual, M Deseada Gutierrez; Zhou, Rui; Smyth, Frank; Anandarajah, Prince M; Barry, Liam P

    2015-09-07

    The authors present the performance and noise properties of a software reconfigurable, FSR and wavelength tunable gain switched optical frequency comb source. This source, based on the external injection of a temperature tuned Fabry-Pérot laser diode, offers quasi-continuous wavelength tunability over the C-band (30nm) and FSR tunability ranging from 6 to 14GHz. The results achieved demonstrate the excellent spectral quality of the comb tones (RIN ~-130dB/Hz and low phase noise of 300kHz) and its outstanding stability (with fluctuations of the individual comb tones of less than 0.5dB in power and 5pm in wavelength, characterized over 24hours) highlighting its suitability for employment in next generation flexible optical transmission networks.

  1. Gain and frequency tuning within the mouse cochlear apex

    SciTech Connect

    Oghalai, John S.; Raphael, Patrick D.; Gao, Simon; Lee, Hee Yoon; Groves, Andrew K.; Zuo, Jian; Applegate, Brian E.

    2015-12-31

    Normal mammalian hearing requires cochlear outer hair cell active processes that amplify the traveling wave with high gain and sharp tuning, termed cochlear amplification. We have used optical coherence tomography to study cochlear amplification within the apical turn of the mouse cochlea. We measured not only classical basilar membrane vibratory tuning curves but also vibratory responses from the rest of the tissues that compose the organ of Corti. Basilar membrane tuning was sharp in live mice and broad in dead mice, whereas other regions of the organ of Corti demonstrated phase shifts consistent with additional filtering beyond that provided by basilar membrane mechanics. We use these experimental data to support a conceptual framework of how cochlear amplification is tuned within the mouse cochlear apex. We will also study transgenic mice with targeted mutations that affect different biomechanical aspects of the organ of Corti in an effort to localize the underlying processes that produce this additional filtering.

  2. Gain-Scheduled Fault Tolerance Control Under False Identification

    NASA Technical Reports Server (NTRS)

    Shin, Jong-Yeob; Belcastro, Christine (Technical Monitor)

    2006-01-01

    An active fault tolerant control (FTC) law is generally sensitive to false identification since the control gain is reconfigured for fault occurrence. In the conventional FTC law design procedure, dynamic variations due to false identification are not considered. In this paper, an FTC synthesis method is developed in order to consider possible variations of closed-loop dynamics under false identification into the control design procedure. An active FTC synthesis problem is formulated into an LMI optimization problem to minimize the upper bound of the induced-L2 norm which can represent the worst-case performance degradation due to false identification. The developed synthesis method is applied for control of the longitudinal motions of FASER (Free-flying Airplane for Subscale Experimental Research). The designed FTC law of the airplane is simulated for pitch angle command tracking under a false identification case.

  3. Optimal gain-to-loss ratio for COIL and EOIL

    NASA Astrophysics Data System (ADS)

    Mezhenin, A. V.

    2017-01-01

    The two-level generation model has been applied to analyze the dependence of power efficiency of chemical oxygen-iodine laser (COIL) and electric oxygen-iodine laser (EOIL) on three dimensionless similarity criteria: residence-to-extraction time ratio γd, gain-to-loss ratio Π and relaxation-to-excitation rate ratio Λ. Power efficiency is represented as the product of two factors - the medium extraction efficiency and the extraction efficiency of resonator - each being a function of the Π. The dependences of the similarity criteria γd and Π optimal values on the kinetic and optical losses have been found. At low kinetic and optical losses, it is expedient to work with high values of γd and Π respectively. It has been found that maximum power efficiency is achieved when Π=3-8 for COIL and Π=9-17 for EOIL at the typical γd and optical losses rate.

  4. Social dilemma alleviated by sharing the gains with immediate neighbors

    NASA Astrophysics Data System (ADS)

    Wu, Zhi-Xi; Yang, Han-Xin

    2014-01-01

    We study the evolution of cooperation in the evolutionary spatial prisoner's dilemma game (PDG) and snowdrift game (SG), within which a fraction α of the payoffs of each player gained from direct game interactions is shared equally by the immediate neighbors. The magnitude of the parameter α therefore characterizes the degree of the relatedness among the neighboring players. By means of extensive Monte Carlo simulations as well as an extended mean-field approximation method, we trace the frequency of cooperation in the stationary state. We find that plugging into relatedness can significantly promote the evolution of cooperation in the context of both studied games. Unexpectedly, cooperation can be more readily established in the spatial PDG than that in the spatial SG, given that the degree of relatedness and the cost-to-benefit ratio of mutual cooperation are properly formulated. The relevance of our model with the stakeholder theory is also briefly discussed.

  5. High gain GaAs photoconductive semiconductor switches: Switch longevity

    SciTech Connect

    Loubriel, G.M.; Zutavern, F.J.; Mar, A.

    1998-07-01

    Optically activated, high gain GaAs switches are being tested for many different pulsed power applications that require long lifetime (longevity). The switches have p and n contact metallization (with intentional or unintentional dopants) configured in such a way as to produce p-i-n or n-i-n switches. The longevity of the switches is determined by circuit parameters and by the ability of the contacts to resist erosion. This paper will describe how the switches performed in test-beds designed to measure switch longevity. The best longevity was achieved with switches made with diffused contacts, achieving over 50 million pulses at 10 A and over 2 million pulses at 80 A.

  6. Marketing of social services gains prominence in practice.

    PubMed

    Stoner, M R

    1986-01-01

    The author reviews the growth and development of social marketing practice as a social work strategy and describes how the different categories of marketing correspond to administrative, planning, and community organization practice. She illustrates the similarity between the social planning process and the market planning process in an effort to demonstrate that social marketing is a useful addition to decision making and planning in social service agencies. Social marketing theory, diffusion theory, and exchange theory provide the theoretical frameworks for the argument developed. Drawing upon these theories, the paper draws attention to the fact that marketing is rapidly gaining acceptance as a viable strategy in macro practice designed to attract and retain consumers of services, develop resources, and inform service providers and practitioners of practice issues and innovations.

  7. Should pollution reductions count as productivity gains for agriculture?

    SciTech Connect

    Smith, V.K.

    1998-08-01

    Productivity changes have been used to gauge economic performance for at least fifty years. Because productivity measures have been so closely linked to changes in living standards, it is natural to ask whether net increases in marketed outputs are the only things that should count as gains to the standard of living. The articles by Faere and Grosskopf (FG) and Gollop and Swinand (GS) consider several different technical aspects of addressing this question. The purpose of this article is to comment on their proposals. Both articles implicitly accept the notion that changes in commodities that are not available in markets should be considered in evaluating performance. Faere and Grosskopf focus on how they should be valued in the productivity indexes, while Gollop and Swinand define conditions when pollution reductions can be allowed to count. The best overall summary of this comment on both papers repeat an overworked phrase--the devil is in the details.

  8. Gain-of-function experiments: time for a real debate.

    PubMed

    Duprex, W Paul; Fouchier, Ron A M; Imperiale, Michael J; Lipsitch, Marc; Relman, David A

    2015-01-01

    According to the WHO, dual use research of concern (DURC) is "life sciences research that is intended for benefit, but which might easily be misapplied to do harm". Recent studies, particularly those on influenza viruses, have led to renewed attention on DURC, as there is an ongoing debate over whether the benefits of gain-of-function (GOF) experiments that result in an increase in the transmission and/or pathogenicity of potential pandemic pathogens (PPPs) are outweighed by concerns over biosecurity and biosafety. In this Viewpoint article, proponents and opponents of GOF experiments discuss the benefits and risks associated with these studies, as well as the implications of the current debate for the scientific community and the general public, and suggest how the current discussion should move forward.

  9. Young children's analogical problem solving: gaining insights from video displays.

    PubMed

    Chen, Zhe; Siegler, Robert S

    2013-12-01

    This study examined how toddlers gain insights from source video displays and use the insights to solve analogous problems. The sample of 2- and 2.5-year-olds viewed a source video illustrating a problem-solving strategy and then attempted to solve analogous problems. Older, but not younger, toddlers extracted the problem-solving strategy depicted in the video and spontaneously transferred the strategy to solve isomorphic problems. Transfer by analogy from the video was evident only when the video illustrated the complete problem goal structure, including the character's intention and the action needed to achieve a goal. The same action isolated from the problem-solving context did not serve as an effective source analogue. These results illuminate the development of early representation and processes involved in analogical problem solving. Theoretical and educational implications are discussed.

  10. Optical Sensitivity Gain in Silica-Coated Plasmonic Nanostructures.

    PubMed

    Floris, Francesco; Figus, Cristiana; Fornasari, Lucia; Patrini, Maddalena; Pellacani, Paola; Marchesini, Gerardo; Valsesia, Andrea; Artizzu, Flavia; Marongiu, Daniela; Saba, Michele; Mura, Andrea; Bongiovanni, Giovanni; Marabelli, Franco; Quochi, Francesco

    2014-09-04

    Ultrathin films of silica realized by sol-gel synthesis and dip-coating techniques were successfully applied to predefined metal/polymer plasmonic nanostructures to spectrally tune their resonance modes and to increase their sensitivity to local refractive index changes. Plasmon resonance spectral shifts up to 100 nm with slope efficiencies of ∼8 nm/nm for increasing layer thickness were attained. In the ultrathin layer regime (<10 nm), which could be reached by suitable dilution of the silica precursors and optimization of the deposition speed, the sensitivity of the main plasmonic resonance to refractive index changes in aqueous solution could be increased by over 50% with respect to the bare plasmonic chip. Numerical simulations supported experimental data and unveiled the mechanism responsible for the optical sensitivity gain, proving an effective tool in the design of high-performance plasmonic sensors.

  11. Edge cladding gain media according to IL-11317

    SciTech Connect

    Soules, T

    2005-02-10

    In this patent application we wish to claim the following approach to ameliorating spontaneous amplified emission (ASE) that occurs in a laser amplifier slab. There are two important elements of our approach. We wish to claim the application of both together but not either one alone. (1) The first element of the invention is to roughen the edge surfaces of the amplifier slab. A rough surface with random planar features larger than the wavelength of light will reflect and refract incident light rays at angles different than the median plane of the surface. The rough surface can then be characterized by two parameters. First there is a distribution of heights about the zero mean plane of the surface. If normal this distribution is characterized by a standard deviation. The second parameter is the correlation distance that describes how close together on average are the peaks and valleys. The ratio of these two numbers determines the spread of light reflected off the surface of the edge of the slab. (2) The second element in our invention is to bond the roughened edges of the gain medium to an ASE absorbing media using a suitable bonding agent. In order for the ASE to leave the gain medium crystal there must be minimal reflection and maximum transmission at the interface. This requires having a near match of the index of refraction of the bonding medium and the amplifier slab material at the wavelength of the ASE. Further if the index of refraction of the bonding agent is less than that of the amplifier there will be some total internal reflection even if the surface is roughened. The index of refraction of GGG is {approx} 1.92 and that of YAG is {approx} 1.84. There are no suitable bonding agents with indices of refraction this high.

  12. Continental Heat Gain in the Global Climate System

    NASA Astrophysics Data System (ADS)

    Smerdon, J. E.; Beltrami, H.; Pollack, H. N.; Huang, S.

    2001-12-01

    Observed increases in 20th century surface-air temperatures are one consequence of a net energy flux into all major components of the Earth climate system including the atmosphere, ocean, cryosphere, and lithosphere. Levitus et al. [2001] have estimated the heat gained by the atmosphere, ocean and cryosphere as 18.2x1022 J, 6.6x1021 J, and 8.1x1021 J, respectively, over the past half-century. However the heat gain of the lithosphere via a heat flux across the solid surface of the continents (30% of the Earth's surface) was not addressed in the Levitus analysis. Here we calculate that final component of Earth's changing energy budget, using ground-surface temperature reconstructions for the continents [Huang et al., 2000]. These reconstructions have shown a warming of at least 0.5 K in the 20th century and were used to determine the flux estimates presented here. In the last half-century, the interval of time considered by Levitus et al., there was an average flux of 40 mW/m2 across the land surface into the subsurface, leading to 9.2x1021 J absorbed by the ground. This amount of heat is significantly less than the energy transferred into the oceans, but of the same magnitude as the energy absorbed by the atmosphere or cryosphere. The heat inputs into all the major components of the climate system - atmosphere, ocean, cryosphere, lithosphere - conservatively sum to more than 20x1022 J during the last half-century, and reinforce the conclusion that the warming in this interval has been truly global. Huang, S., Pollack, H.N., and Shen, P.-Y. 2000. Temperature trends over the past five centuries reconstructed from borehole temperatures. Nature. 403. 756-758 Levitus, S., Antonov, J., Wang, J., Delworth, T. L., Dixon, K. and Broccoli, A. 2001. Anthropogenic warming of the Earth's climate system. Science, 292, 267-270

  13. Small-signal gain in a gas-loaded FEL

    SciTech Connect

    Goloviznin, V.V.; Amersfoort, P.W. van

    1995-12-31

    At present, existing FEL facilities operate in the infrared and visible ranges of wavelengths. Generation of shorter waves (in the VUV and X-ray region) is of great scientific interest, but this would require a very expensive accelerator which could provide a high-current electron beam in the GeV-range of energies. A promising way to relax requirements on electron energy by introduction of a gas into the optical cavity was proposed nearly ten years ago. For small deviations from the vacuum wavelength, the idea was confirmed in experiments performed in Stanford; however, a detailed theory of such a device is still not developed. We present an analysis of the small-signal gain in a gas-loaded free-electron laser. Multiple scattering of electrons by the atoms of the gas inside the optical cavity is shown to lead to two additional effects, as compared to the case of a vacuum FEL: a loss of coherence between different parts of the electron trajectory and an enhancement of the phase {open_quotes}jitter{close_quotes}. Both effects become increasingly important at short wavelengths and significantly reduce the small-signal gain per pass. In 1D approximation analytical expressions are obtained and numerical calculations are made to estimate beam and undulator parameters necessary for lasing in the vacuum ultraviolet. Hydrogen-filled FELs are shown to have good prospects for this at today`s technological level. To operate in the range of wavelengths 125-140 nm, an electron beam should have an energy above 50 MeV and a good quality: a normalised emittance of the order of 5{pi} mm-mrad and an energy spread below 10{sup -3}. All these parameters are achieveable with modern linacs and photoinjectors.

  14. Quantitative aspects of gain and latency in the cat retina

    PubMed Central

    Cleland, B. G.; Enroth-Cugell, Christina

    1970-01-01

    1. The gain of the central response mechanism and the latency of the pure central response of on-centre ganglion cells were studied by recording from single optic tract fibres the responses evoked by slow square-wave stimuli applied against some steady background. 2. The concept of effective flux was introduced and defined: if any portion of a stimulus extends beyond Ricco's area of complete summation, then that stimulus has an actual flux, equal to the product of its area and luminance, but it also has an effective flux which is that fraction of its actual flux which equals the actual flux of another stimulus which, when it falls entirely within Ricco's area, evokes an isobolic pure central response or has the same adaptive effect upon the central response mechanism as the first stimulus. 3. The most significant finding was that when the cell responded with a pure central response to the incremental flux (the square wave) applied against a steady effective background flux, then the gain and the latency were functions exclusively of the sum of the two fluxes (the total flux), not of the incremental or background flux as such. This shows that the level of field adaptation of the central mechanism is reset within the latent period of the response to an incremental flux. 4. Increment sensitivity curves based on isobolic suprathreshold responses all had the same slope of 0·9, when the log of the incremental flux was plotted against the log of the total flux. A plot of log latency against log total effective flux had a slope of -0·1. 5. The stimulus—response relation derived from (3) and (4) was [Formula: see text] and [Formula: see text], where R is the response amplitude, Fet the total flux, ΔFe the incremental flux and K1 and K2 are constants. PMID:5498461

  15. Small weight gains during obesity treatment: normative or cause for concern?

    PubMed Central

    Gaspar, Monika; Remmert, Jocelyn E.; Zhang, Fengqing; Forman, Evan M.; Butryn, Meghan L.

    2016-01-01

    Summary Objectives The objectives of the study are to characterize the frequency and size of small weight gains during behavioural weight loss treatment and to evaluate the relationship between small weight gains and weight loss outcomes. Methods Participants (n = 281) in a year‐long behavioural weight loss programme were weighed at treatment sessions, and between‐session weight gains were classified into several categories based on size. The occurrence of different gain magnitudes and their relation to weight loss were examined during both the active weight loss (months 1–6) and weight loss maintenance (months 7–12) phases of treatment. Results Weight gains were common during both phases of treatment, with smaller gains occurring more frequently than larger gains. Greater frequency of all gain magnitudes was associated with lesser weight loss during both phases. Additionally, participants who had just one or two weight gains of the smallest size examined (1.0–1.9 lb) lost less weight than those who had no gains. Conclusions Small gains appear to reflect true weight gain due to poor adherence to behavioural recommendations and are associated with worse weight loss outcomes, even when limited in number. Future research should examine how best to prevent small weight gains from occurring and how clinicians and participants should respond when a weight gain does occur to promote weight control success. PMID:28090341

  16. Loop gain stabilizing with an all-digital automatic-gain-control method for high-precision fiber-optic gyroscope.

    PubMed

    Zheng, Yue; Zhang, Chunxi; Li, Lijing; Song, Lailiang; Chen, Wen

    2016-06-10

    For a fiber-optic gyroscope (FOG) using electronic dithers to suppress the dead zone, without a fixed loop gain, the deterministic compensation for the dither signals in the control loop of the FOG cannot remain accurate, resulting in the dither residuals in the FOG rotation rate output and the navigation errors in the inertial navigation system. An all-digital automatic-gain-control method for stabilizing the loop gain of the FOG is proposed. By using a perturbation square wave to measure the loop gain of the FOG and adding an automatic gain control loop in the conventional control loop of the FOG, we successfully obtain the actual loop gain and make the loop gain converge to the reference value. The experimental results show that in the case of 20% variation in the loop gain, the dither residuals are successfully eliminated and the standard deviation of the FOG sampling outputs is decreased from 2.00  deg/h to 0.62  deg/h (sampling period 2.5 ms, 10 points smoothing). With this method, the loop gain of the FOG can be stabilized over the operation temperature range and in the long-time application, which provides a solid foundation for the engineering applications of the high-precision FOG.

  17. Electrical and Optical Gain Lever Effects in InGaAs Double Quantum Well Diode Lasers

    SciTech Connect

    Pocha, M D; Goddard, L L; Bond, T C; Nikolic, R J; Vernon, S P; Kallman, J S; Behymer, E M

    2007-01-03

    In multisection laser diodes, the amplitude or frequency modulation (AM or FM) efficiency can be improved using the gain lever effect. To study gain lever, InGaAs double quantum well (DQW) edge emitting lasers have been fabricated with integrated passive waveguides and dual sections providing a range of split ratios from 1:1 to 9:1. Both the electrical and the optical gain lever have been examined. An electrical gain lever with greater than 7 dB enhancement of AM efficiency was achieved within the range of appropriate DC biasing currents, but this gain dropped rapidly outside this range. We observed a 4 dB gain in the optical AM efficiency under non-ideal biasing conditions. This value agreed with the measured gain for the electrical AM efficiency under similar conditions. We also examined the gain lever effect under large signal modulation for digital logic switching applications. To get a useful gain lever for optical gain quenched logic, a long control section is needed to preserve the gain lever strength and a long interaction length between the input optical signal and the lasing field of the diode must be provided. The gain lever parameter space has been fully characterized and validated against numerical simulations of a semi-3D hybrid beam propagation method (BPM) model for the coupled electron-photon rate equation. We find that the optical gain lever can be treated using the electrical injection model, once the absorption in the sample is known.

  18. Galileo mission planning for Low Gain Antenna based operations

    NASA Technical Reports Server (NTRS)

    Gershman, R.; Buxbaum, K. L.; Ludwinski, J. M.; Paczkowski, B. G.

    1994-01-01

    The Galileo mission operations concept is undergoing substantial redesign, necessitated by the deployment failure of the High Gain Antenna, while the spacecraft is on its way to Jupiter. The new design applies state-of-the-art technology and processes to increase the telemetry rate available through the Low Gain Antenna and to increase the information density of the telemetry. This paper describes the mission planning process being developed as part of this redesign. Principal topics include a brief description of the new mission concept and anticipated science return (these have been covered more extensively in earlier papers), identification of key drivers on the mission planning process, a description of the process and its implementation schedule, a discussion of the application of automated mission planning tool to the process, and a status report on mission planning work to date. Galileo enhancements include extensive reprogramming of on-board computers and substantial hard ware and software upgrades for the Deep Space Network (DSN). The principal mode of operation will be onboard recording of science data followed by extended playback periods. A variety of techniques will be used to compress and edit the data both before recording and during playback. A highly-compressed real-time science data stream will also be important. The telemetry rate will be increased using advanced coding techniques and advanced receivers. Galileo mission planning for orbital operations now involves partitioning of several scarce resources. Particularly difficult are division of the telemetry among the many users (eleven instruments, radio science, engineering monitoring, and navigation) and allocation of space on the tape recorder at each of the ten satellite encounters. The planning process is complicated by uncertainty in forecast performance of the DSN modifications and the non-deterministic nature of the new data compression schemes. Key mission planning steps include

  19. Terahertz Amplifier Based On Gain Switching In a Quantum Cascade Laser

    NASA Astrophysics Data System (ADS)

    Jukam, N.; Rungsawang, R.; Dhillon, S. S.; Oustinov, D.; Madéo, J.; Barbieri, S.; Manquest, C.; Sirtori, C.; Khanna, S. P.; Linfield, E.; Davies, A. G.; Tignon, J.

    2011-12-01

    A terahertz quantum cascade laser and an integrated Auston-switch are coupled to perform ultrafast gain switching. The resulting non-equilibrium gain is not clamped above laser threshold and large amplification of input terahertz pulses is demonstrated.

  20. Weight gain in pregnancy: is less truly more for mother and infant?

    PubMed Central

    Barbour, Linda A

    2012-01-01

    SUMMARY Although more than 50% of women gain weight above the Institute of Medicine (IOM) guidelines for weight gain in pregnancy and excessive weight gain is an independent risk factor for significant maternal and neonatal morbidity and offspring obesity, there is little consensus over the ideal weight gain during pregnancy. Surprisingly, the 2009 IOM guidelines varied minimally from the 1990 IOM guidelines, and many critics advocate lower weight gain recommendations. This review explores the energy costs of pregnancy, the relationship between gestational weight gain and birth weight, and considers what gestational weight gain minimizes both large-for-gestational age as well as small-for-gestational age infants. An extensive examination of the current data leads this author to question whether the current weight gain recommendations are too liberal, especially for obese pregnant women. PMID:27579137

  1. 26 CFR 1.684-3 - Exceptions to general rule of gain recognition.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... section 1032 applies. The general rule of gain recognition under § 1.684-1 shall not apply to any transfer... corporation is not required to recognize gain on the transfer under section 1032. (f) Certain distributions...

  2. 26 CFR 1.684-3 - Exceptions to general rule of gain recognition.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... section 1032 applies. The general rule of gain recognition under § 1.684-1 shall not apply to any transfer... corporation is not required to recognize gain on the transfer under section 1032. (f) Certain distributions...

  3. 26 CFR 1.684-3 - Exceptions to general rule of gain recognition.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... section 1032 applies. The general rule of gain recognition under § 1.684-1 shall not apply to any transfer... corporation is not required to recognize gain on the transfer under section 1032. (f) Certain distributions...

  4. Utilization of photoconductive gain in a-Si:H devices for radiation detection

    SciTech Connect

    Lee, H.K.; Drewery, J.S.; Hong, W.S.; Jing, T.; Kaplan, S.N.; Perez-Mendez, V.

    1995-05-01

    The photoconductive gain mechanism in a-Si:H was investigated in connection with applications to radiation detection. Various device types such as p-i-n, n-i-n and n-i-p-i-n structures were fabricated and tested. Photoconductive gain was measured in two time scales: one for short pulses of visible light (<1 {mu}sec) which simulates the transit of an energetic charged particle, and the other for rather long pulses of light (1 msec) which simulates x-ray exposure in medical imaging. We used two definitions of photoconductive gain: current gain and charge gain which is an integration of the current gain. We found typical charge gains of 3 {approximately} 9 for short pulses and a few hundred for long pulses at a dark current level of 10 mA/cm{sup 2}. Various gain results are discussed in terms of the device structure, applied bias and dark current.

  5. High-gain nonlinear observer for simple genetic regulation process

    NASA Astrophysics Data System (ADS)

    Torres, L. A.; Ibarra-Junquera, V.; Escalante-Minakata, P.; Rosu, H. C.

    2007-07-01

    High-gain nonlinear observers occur in the nonlinear automatic control theory and are in standard usage in chemical engineering processes. We apply such a type of analysis in the context of a very simple one-gene regulation circuit. In general, an observer combines an analytical differential-equation-based model with partial measurement of the system in order to estimate the non-measured state variables. We use one of the simplest observers, that of Gauthier et al., which is a copy of the original system plus a correction term which is easy to calculate. For the illustration of this procedure, we employ a biological model, recently adapted from Goodwin's old book by De Jong, in which one plays with the dynamics of the concentrations of the messenger RNA coding for a given protein, the protein itself, and a single metabolite. Using the observer instead of the metabolite, it is possible to rebuild the non-measured concentrations of the mRNA and the protein.

  6. Nutrient losses and gains during frying: a review.

    PubMed

    Fillion, L; Henry, C J

    1998-03-01

    Recent consumer interest in 'healthy eating' has raised awareness to limit the consumption of fat and fatty foods. What are the relative nutritional advantages and disadvantages of consuming fried foods? Are all fried foods bad for you? A review on macro- and micronutrients losses and gains during frying is presented here. Frying has little or no impact on the protein or mineral content of fried food, whereas the dietary fibre content of potatoes is increased after frying due to the formation of resistant starch. Moreover, the high temperature and short transit time of the frying process cause less loss of heat labile vitamins than other types of cooking. For example, vitamin C concentrations of French fried potatoes are as high as in raw potatoes, and thiamine is well retained in fried potato products as well as in fried pork meat. The nutritive value of the frying media is also important to take into consideration and therefore losses of nutrients from the frying oil are also discussed. Although some unsaturated fatty acids and antioxidant vitamins are lost due to oxidation, fried foods are generally a good source of vitamin E. It is true that some fat is inevitably taken up by the food being fried, contributing to an increased energy density. However, this also results in highly palatable foods with a high nutritional content. It is concluded that fried foods certainly have a place in our diets.

  7. Difficult communication: compliance-gaining strategies of organ procurement coordinators.

    PubMed

    Anker, Ashley E; Feeley, Thomas Hugh

    2011-04-01

    Organ procurement coordinators (OPCs) face a formidable communication task when making familial requests for consent to organ donation, because they must provide social support for grieving family members while seeking compliance to the donation request. Structured interviews were conducted with 102 OPCs, representing 16 organ procurement organizations (OPOs) (27.6% of national organizations) across the United States. Responses were transcribed and content-analyzed along four domain areas: (a) establishing credibility, (b) message strategies, (c) timing/setting of requests, and (d) adaptation of messages to diverse families. OPO conversion rates were used as a criterion factor for OPCs' persuasive communication success and regressed onto self-reported strategy use. Results indicate message strategies varied at the OPC level of analysis and 7 techniques significantly predicted 32% of the variance in conversion rates. Two strategies (i.e., gaining early intervention, approaching with additional support) positively influenced conversion rates, whereas 5 strategies (e.g., discussing benefits as a persuasive strategy, emphasizing the need for donation in particular racial/ethnic groups) negatively influenced conversion rates. Future research is recommended to validate the study findings toward the goal of improving OPCs' communication strategies.

  8. [Unexplained weight gain in a 41-year-old woman].

    PubMed

    Harsch, I A; Hahn, E G

    2010-03-01

    A 41-year-old female was admitted to our clinic due to weight gain and facial edema. The patient also reported hair loss, amenorrhea and the formation of striae. The laboratory diagnostics ensured the diagnosis of Cushing's syndrome. Unfortunately, the patient was among the 5-10% of patients in whom neither laboratory testing nor imaging revealed the source of the cortisol excess. Due to the dramatic decrease of her general condition, and the appearance of hypertension and diabetes mellitus we chose to refer the patient to bilateral minimally invasive adrenalectomy. The advantage of this therapeutic approach is, that it is a definitive treatment that provides immediate control of hypercortisolism. As disadvantage, the resultant permanent hypoadrenalism requires a lifelong glucocorticoid and mineralocorticoid replacement therapy. Furthermore, given that the problem was caused by occult pituitary microadenoma, Nelson's syndrome has to be considered. As only one adrenal could be excised due to technical reasons, the underlying pathology is thus not solved. In spite of this, the patient's general condition improved dramatically without need for replacement therapy. As the mortality of patients with persistent moderate hypercortisolism is increased 3,8- to 5 fold, mainly due to cardiovascular reasons, thorough surveillance for signs of recurrence is mandatory to be ready for quick intervention.

  9. High gain pre-amplifier laser beam quality evaluating system

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Yu, Jin; Zhao, Tianzhuo; Zhang, Xue; Fan, Zhongwei

    2011-06-01

    Designed a system for the high gain laser pre-amplifier to evaluate the image quality. The system uses 4f imaging principle and Kepler type telescope was choiced, it has two advantages: avert optical distortion and eliminate aberration in the measurement system. Combined with the location of the lens inside of pre-amplifier such as the spatial filter , the near field imaging structure was designed. The structure can be reduced to 11.9 times the beam image, and clearly passed the image to the CCD target surface. The location of first positive lens focus is the location of far field image. In this article, one laser pre-amplifier was measured. The average measured near field modulation M=1.34, the average measured far field diffraction limit is 2.94. Experiments show that the stability of measuring system is less than+/-5%, it can meet the measurement requirements of ICF laser pre-amplifier parameters. Use this system we can discover the problem during the design and installation. There is great meaning for develop of laser pre-amplifier in ICF for further.

  10. Multidimensional gain control in image representation and processing in vision.

    PubMed

    Furman, S; Zeevi, Y Y

    2015-04-01

    A generic model of automatic gain control (AGC) is proposed as a general framework for multidimensional automatic contrast sensitivity adjustment in vision, as well as in other sensory modalities. We show that a generic feedback AGC mechanism, incorporating a nonlinear synaptic interaction into the feedback loop of a neural network, can enhance and emphasize important image attributes, such as curvature, size, depth, convexity/concavity and more, similar to its role in the adjustment of photoreceptors and retinal network sensitivity over the extremely high dynamic range of environmental light intensities, while enhancing the contrast. We further propose that visual illusions, well established by psychophysical experiments, are a by-product of the multidimensional AGC. This hypothesis is supported by simulations implementing AGC, which reproduce psychophysical data regarding size contrast effects known as the Ebbinghaus illusion, and depth contrast effects. Processing of curvature by an AGC network illustrates that it is an important mechanism of image structure pre-emphasis, which thereby enhances saliency. It is argued that the generic neural network of AGC constitutes a universal, parsimonious, unified mechanism of neurobiological automatic contrast sensitivity control. This mechanism/model can account for a wide range of physiological and psychophysical phenomena, such as visual illusions and contour completion, in cases of occlusion, by a basic neural network. Likewise, and as important, biologically motivated AGC provides attractive new means for the development of intelligent computer vision systems.

  11. Boreal feather mosses secrete chemical signals to gain nitrogen.

    PubMed

    Bay, Guillaume; Nahar, Nurun; Oubre, Matthieu; Whitehouse, Martin J; Wardle, David A; Zackrisson, Olle; Nilsson, Marie-Charlotte; Rasmussen, Ulla

    2013-10-01

    The mechanistic basis of feather moss-cyanobacteria associations, a main driver of nitrogen (N) input into boreal forests, remains unknown. Here, we studied colonization by Nostoc sp. on two feather mosses that form these associations (Pleurozium schreberi and Hylocomium splendens) and two acrocarpous mosses that do not (Dicranum polysetum and Polytrichum commune). We also determined how N availability and moss reproductive stage affects colonization, and measured N transfer from cyanobacteria to mosses. The ability of mosses to induce differentiation of cyanobacterial hormogonia, and of hormogonia to then colonize mosses and re-establish a functional symbiosis was determined through microcosm experiments, microscopy and acetylene reduction assays. Nitrogen transfer between cyanobacteria and Pleurozium schreberi was monitored by secondary ion mass spectrometry (SIMS). All mosses induced hormogonia differentiation but only feather mosses were subsequently colonized. Colonization on Pleurozium schreberi was enhanced during the moss reproductive phase but impaired by elevated N. Transfer of N from cyanobacteria to their host moss was observed. Our results reveal that feather mosses likely secrete species-specific chemo-attractants when N-limited, which guide cyanobacteria towards them and from which they gain N. We conclude that this signalling is regulated by N demands of mosses, and serves as a control of N input into boreal forests.

  12. Leveraging prognostic baseline variables to gain precision in randomized trials.

    PubMed

    Colantuoni, Elizabeth; Rosenblum, Michael

    2015-08-15

    We focus on estimating the average treatment effect in a randomized trial. If baseline variables are correlated with the outcome, then appropriately adjusting for these variables can improve precision. An example is the analysis of covariance (ANCOVA) estimator, which applies when the outcome is continuous, the quantity of interest is the difference in mean outcomes comparing treatment versus control, and a linear model with only main effects is used. ANCOVA is guaranteed to be at least as precise as the standard unadjusted estimator, asymptotically, under no parametric model assumptions and also is locally semiparametric efficient. Recently, several estimators have been developed that extend these desirable properties to more general settings that allow any real-valued outcome (e.g., binary or count), contrasts other than the difference in mean outcomes (such as the relative risk), and estimators based on a large class of generalized linear models (including logistic regression). To the best of our knowledge, we give the first simulation study in the context of randomized trials that compares these estimators. Furthermore, our simulations are not based on parametric models; instead, our simulations are based on resampling data from completed randomized trials in stroke and HIV in order to assess estimator performance in realistic scenarios. We provide practical guidance on when these estimators are likely to provide substantial precision gains and describe a quick assessment method that allows clinical investigators to determine whether these estimators could be useful in their specific trial contexts.

  13. Association between Stock Market Gains and Losses and Google Searches

    PubMed Central

    Arditi, Eli; Yechiam, Eldad; Zahavi, Gal

    2015-01-01

    Experimental studies in the area of Psychology and Behavioral Economics have suggested that people change their search pattern in response to positive and negative events. Using Internet search data provided by Google, we investigated the relationship between stock-specific events and related Google searches. We studied daily data from 13 stocks from the Dow-Jones and NASDAQ100 indices, over a period of 4 trading years. Focusing on periods in which stocks were extensively searched (Intensive Search Periods), we found a correlation between the magnitude of stock returns at the beginning of the period and the volume, peak, and duration of search generated during the period. This relation between magnitudes of stock returns and subsequent searches was considerably magnified in periods following negative stock returns. Yet, we did not find that intensive search periods following losses were associated with more Google searches than periods following gains. Thus, rather than increasing search, losses improved the fit between people’s search behavior and the extent of real-world events triggering the search. The findings demonstrate the robustness of the attentional effect of losses. PMID:26513371

  14. Improving microwave antenna gain and bandwidth with phase compensation metasurface

    NASA Astrophysics Data System (ADS)

    Chen, Ke; Yang, Zhongjie; Feng, Yijun; Zhu, Bo; Zhao, Junming; Jiang, Tian

    2015-06-01

    Metasurface, as a planar version of artificial metamaterial, provide an effective way to manipulate electromagnetic wave propagation. Here, we present a transparent metasurface for compensating the out-of-phase radiation from a microstrip patch antenna to improve its radiation gain and bandwidth. Based on the equivalence principle of Huygens' surface, we propose metasurface composed of both inductive and capacitive resonant elements which could produce high transmission with variable phase characteristics. Such metasurface mounted on a patch antenna can transform the spherical-like phase profile generated from the patch into an in-phase planar one. A prototype antenna has been fabricated and validated the squeezed radiation pattern with suppressed sidelobes as well as enhanced impedance bandwidth due to strong near-field coupling. As operating at around 5.7 GHz, the proposed antenna may have potential application in wireless communication systems especially for point-to-point data transmission. It is believed that the design methodology could also be scaled to other frequency bands such as millimeter or terahertz wave.

  15. Thermal Characterization of a Direct Gain Solar Thermal Engine

    NASA Technical Reports Server (NTRS)

    Alexander, Reginald A.; Coleman, Hugh W.

    1999-01-01

    A thermal/fluids analysis of a direct gain solar thermal upper stage engine is presented and the results are discussed. The engine was designed and constructed at the NASA Marshall Space Flight Center for ground testing in a facility that can provide about 10 kilowatts of concentrated solar energy to the engine. The engine transfers energy to a coolant (hydrogen) that is heated and accelerated through a nozzle to produce thrust. For the nominal design values and a hydrogen flowrate of 2 lb./hr., the results of the analysis show that the hydrogen temperature in the chamber (nozzle entrance) reaches about 3800 F after 30 minutes of heating and about 3850 F at steady-state (slightly below the desired design temperature of about 4100 F. Sensitivity analyses showed these results to be relatively insensitive to the values used for the absorber surface infrared emissivity and the convection coefficient within the cooling ducts but very sensitive to the hydrogen flowrate. Decreasing the hydrogen flowrate to 1 lb./hr. increases the hydrogen steady-state chamber temperature to about 4700 F, but also of course causes a decrease in thrust.

  16. Thermal Characterization of a Direct Gain Solar Thermal Engine

    NASA Technical Reports Server (NTRS)

    Alexander, Reginald A.; Coleman, Hugh W.

    1998-01-01

    A thermal/fluids analysis of a direct gain solar thermal upper stage engine is presented and the results are discussed. The engine has been designed and constructed at the NASA Marshall Space Flight Center for ground testing in a facility that can provide about 10 kilowatts of concentrated solar energy to the engine. The engine transfers that energy to a coolant (hydrogen) that is heated and accelerated through a nozzle to produce thrust. For the nominal design values and a hydrogen flowrate of 2 lb/hr., the results of the analysis show that the hydrogen temperature in the chamber (nozzle entrance) reaches about 3800 F after 30 minutes of heating and about 3850 F at steady-state (slightly below the desired design temperature of about 4100 F). Sensitivity analyses showed these results to be relatively insensitive to the values used for the absorber surface infrared emissivity and the convection coefficient within the cooling ducts but very sensitive to the hydrogen flowrate. Decreasing the hydrogen flowrate to 1 lb/hr. increases the hydrogen steady-state chamber temperature to about 4700 F, but also causes an undesirable decrease in thrust.

  17. Gestational weight gain and offspring longitudinal growth in early life

    PubMed Central

    Diesel, Jill C.; Eckhardt, Cara L.; Day, Nancy L.; Brooks, Maria M.; Arslanian, Silva A.; Bodnar, Lisa M.

    2015-01-01

    Background Excessive gestational weight gain (GWG) increases the risk of childhood obesity, but little is known about its association with infant growth patterns. Aim To examine the GWG-infant growth association. Methods Pregnant women (n=743) self-reported GWG at delivery, which we classified as inadequate, adequate, or excessive based on current guidelines. Offspring weight-for-age z-scores (WAZ), length-for-age z-scores (LAZ (with height-for-age (HAZ) in place of length at 36 months)), and body mass index z-scores (BMIZ) were calculated at birth, 8, 18, and 36 months using the 2006 WHO growth standards. Linear mixed models estimated the change in z-scores from birth to 36 months by GWG. Results The mean (SD) WAZ was −0.22 (1.20) at birth. Overall, WAZ and BMIZ increased from birth to approximately 24 months and decreased from 24 to 36 months, while LAZ/HAZ decreased from birth through 36 months. Excessive GWG was associated with higher offspring WAZ and BMIZ at birth, 8, and 36 months, and higher HAZ at 36 months, compared with adequate GWG. Compared with the same referent, inadequate GWG was associated with smaller WAZ and BMIZ at birth and 8 months. Conclusion Excessive GWG may predispose infants to obesogenic growth patterns while inadequate GWG may not have a lasting impact on infant growth. PMID:26279171

  18. Thirst distress and interdialytic weight gain: how do they relate?

    PubMed

    Jacob, Sheena; Locking-Cusolito, Heather

    2004-01-01

    Thirst is a frequent and stressful symptom experienced by hemodialysis patients. Several studies have noted a positive relationship between thirst and interdialytic weight gain (IDWG). These factors prompted us to consider ways that we could intervene to reduce thirst and IDWG through an educative, supportive nursing intervention. This paper presents the results of a pilot research project, the purpose of which was to: examine the relationship between thirst distress (the negative symptoms associated with thirst) and IDWG in a sample of our patients, describe patients' strategies for management of thirst, and establish the necessary sample size for the planned intervention study. The pilot research project results showed that in a small sample of 20, there was a mildly positive, though not statistically significant, correlation between thirst distress and IDWG (r = 0.117). Subjects shared a wide variety of thirst management strategies including: limiting salt intake, using ice chips, measuring daily allotment, performing mouth care, eating raw fruits and vegetables, sucking on hard candy and chewing gum. This pilot research project showed that given an alpha of 0.05 and a power of 80%, we will require a sample of 39 subjects to detect a 20% change in IDWG. We will employ these results to plan our intervention study, first by establishing the appropriate sample size and second by incorporating identified patient strategies into an educational pamphlet that will form the basis of our intervention.

  19. Gestational Weight Gain in Japanese Women With Favorable Perinatal Outcomes

    PubMed Central

    Suzuki, Shunji

    2017-01-01

    Background We examined the optimal gestational weight gain (GWG) in the healthy Japanese women with favorable perinatal outcomes of singleton pregnancy. Methods We calculated the average GWG in the women whose height was 150 - 164 cm with favorable perinatal outcomes set for this study. The women were categorized to underweight, normal, overweight and obese based on the pre-pregnancy body mass index categories according to the Institute of Medicine guideline. Results The average GWG in the normal-weight women with the favorable perinatal outcomes was 11.4 ± 3.7 kg. It was not significantly different from that in the underweight and overweight women (12.0 ± 3.4 and 10.0 ± 4.8 kg) by Student’s t-test. The average GWG in the obese women was significantly lower than that in the other three groups (3.2 ± 2.2 kg, P < 0.01). Conclusion Based on the current results, the optimal GWG for the Japanese women without obesity was found to be 10 - 12 kg. PMID:27924177

  20. Animated Ranking Tasks: Student Attitudes, Practices, & Learning Gains

    NASA Astrophysics Data System (ADS)

    Lee, Kevin M.; Prather, E. E.; Collaboration of Astronomy Teaching Scholars CATS

    2012-01-01

    A ranking task typically provides the learner with a series of pictures or diagrams that describe several slightly different variations of a basic physical situation. The student is then asked to make a comparative judgment and order or rank the various situations based on some physical outcome or result. These novel and intellectually challenging tasks effectively probe student understanding at a deep conceptual level. For several years we have been developing a library of computer-based ranking and sorting tasks for introductory astronomy. The students in this study completed a series of animated ranking tasks on lunar phases, were surveyed regarding their experiences, and completed a pre/post assessment based on Lunar Phase Concept Inventory questions. The tasks communicated with a database and all student interactions were recorded. This poster will detail student learning gains, practices, and attitudes from the study. Interesting correlations between variables will be identified. All eduational tools described in this poster are publicly available at http://astro.unl.edu. This material is based upon work supported by the National Science Foundation under Grants Nos. 0737376 and 0715517, a CCLI Phase III Grant for the Collaboration of Astronomy Teaching Scholars (CATS). Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation.