Numeral size, spacing between targets, and exposure time in discrimination by elderly people using an lcd monitor.

PubMed

Huang, Kuo-Chen; Yeh, Po-Chan

2007-04-01

The present study investigated the effects of numeral size, spacing between targets, and exposure time on the discrimination performance by elderly and younger people using a liquid crystal display screen. Analysis showed size of numerals significantly affected discrimination, which increased with increasing numeral size. Spacing between targets also had a significant effect on discrimination, i.e., the larger the space between numerals, the better their discrimination. When the spacing between numerals increased to 4 or 5 points, however, discrimination did not increase beyond that for 3-point spacing. Although performance increased with increasing exposure time, the difference in discrimination at an exposure time of 0.8 vs 1.0 sec. was not significant. The accuracy by the elderly group was less than that by younger subjects.

Increasing Performance of Professional Soccer Players and Elite Track and Field Athletes with Peak Performance Training and Biofeedback: A Pilot Study.

PubMed

Rijken, Noortje H; Soer, Remko; de Maar, Ewold; Prins, Hilco; Teeuw, Wouter B; Peuscher, Jan; Oosterveld, Frits G J

2016-12-01

The aim of this pilot study was to investigate the effects of an intervention consisting of mental coaching combined with either electro encephalogram (EEG) alpha power feedback or heart rate variability (HRV) feedback on HRV, EEG outcomes and self-reported factors related to stress, performance, recovery and sleep quality in elite athletes. A prospective pilot study was performed with two distinct cohorts. Soccer players were provided with four sessions of mental coaching combined with daily HRV biofeedback (Group A); track and field athletes were provided with four sessions of mental coaching in combination with daily neurofeedback (Group B). Measurements were performed at baseline, post intervention and at 5 weeks follow-up. Objective measures: EEG and ECG. Subjective measures: Numeric Rating Scale for performance, Pittsburgh Sleep Quality Index, Rest and Stress Questionnaire and Sports Improvement-60. Group characteristics were too distinct to compare the interventions. Linear mixed models were used to analyze differences within groups over time. In Group A, significant changes over time were present in alpha power at 5 of 7 EEG locations (p < 0.01-0.03). LF/HF ratio significantly increased (p = 0.02) and the concentration (p = 0.02) and emotional scale (p = 0.03) of the SIM-60 increased significantly (p = 0.04). In Group B, the HRV low frequency power and recovery scale of the REST-Q significantly increased (p = 0.02 and <0.01 resp.). Other measures remained stable or improved non-significantly. A mental coaching program combined with either HRV or EEG alpha power feedback may increase HRV and alpha power and may lead to better performance-related outcomes and stress reduction. Further research is needed to elucidate the effects of either type of feedback and to compare effects with a control group.

Intra-operative disruptions, surgeon's mental workload, and technical performance in a full-scale simulated procedure.

PubMed

Weigl, Matthias; Stefan, Philipp; Abhari, Kamyar; Wucherer, Patrick; Fallavollita, Pascal; Lazarovici, Marc; Weidert, Simon; Euler, Ekkehard; Catchpole, Ken

2016-02-01

Surgical flow disruptions occur frequently and jeopardize perioperative care and surgical performance. So far, insights into subjective and cognitive implications of intra-operative disruptions for surgeons and inherent consequences for performance are inconsistent. This study aimed to investigate the effect of surgical flow disruption on surgeon's intra-operative workload and technical performance. In a full-scale OR simulation, 19 surgeons were randomly allocated to either of the two disruption scenarios (telephone call vs. patient discomfort). Using a mixed virtual reality simulator with a computerized, high-fidelity mannequin, all surgeons were trained in performing a vertebroplasty procedure and subsequently performed such a procedure under experimental conditions. Standardized measures on subjective workload and technical performance (trocar positioning deviation from expert-defined standard, number, and duration of X-ray acquisitions) were collected. Intra-operative workload during simulated disruption scenarios was significantly higher compared to training sessions (p < .01). Surgeons in the telephone call scenario experienced significantly more distraction compared to their colleagues in the patient discomfort scenario (p < .05). However, workload tended to be increased in surgeons who coped with distractions due to patient discomfort. Technical performance was not significantly different between both disruption scenarios. We found a significant association between surgeons' intra-operative workload and technical performance such that surgeons with increased mental workload tended to perform worse (β = .55, p = .04). Surgical flow disruptions affect surgeons' intra-operative workload. Increased mental workload was associated with inferior technical performance. Our simulation-based findings emphasize the need to establish smooth surgical flow which is characterized by a low level of process deviations and disruptions.

Work Organization, Technology, and Performance in Customer Service and Sales.

ERIC Educational Resources Information Center

Batt, Rosemary

1999-01-01

Performance data on 223 customer-service and sales representatives showed that participation in self-managed teams correlated with significant improvement in service quality and 9.3% sales increase. New technology helped teams increase sales 17.4%. Total-quality management did not affect performance. Results show that group collaboration fosters…

Comparing the performance-enhancing effects of squats on a vibration platform with conventional squats in recreationally resistance-trained men.

PubMed

Rønnestad, Bent R

2004-11-01

The purpose of this investigation was to compare the performance-enhancing effects of squats on a vibration platform with conventional squats in recreationally resistance-trained men. The subjects were 14 recreationally resistance-trained men (age, 21-40 years) and the intervention period consisted of 5 weeks. After the initial testing, subjects were randomly assigned to either the "squat whole body vibration" (SWBV) group (n = 7), which performed squats on a vibration platform on a Smith Machine, or the "squat"(S) group (n = 7), which performed conventional squats with no vibrations on a Smith Machine. Testing was performed at the beginning and the end of the study and consisted of 1 repetition maximum (1RM) in squat and maximum jump height in countermovement jump (CMJ). A modified daily undulating periodization program was used during the intervention period in both groups. Both groups trained at the same percentage of 1RM in squats (6-10RM). After the intervention, CMJ performance increased significantly only in the SWBV (p < 0.01), but there was no significant difference between groups in relative jump height increase (p = 0.088). Both groups showed significant increases in 1RM performance in squats (p < 0.01). Although there was a trend toward a greater relative strength increase in the SWBV group, it did not reach a significant level. In conclusion, the preliminary results of this study point toward a tendency of superiority of squats performed on a vibration platform compared with squats without vibrations regarding maximal strength and explosive power as long as the external load is similar in recreationally resistance-trained men.

Effects of Tribulus terrestris saponins on exercise performance in overtraining rats and the underlying mechanisms.

PubMed

Yin, Liang; Wang, Qian; Wang, Xiaohui; Song, Liang-Nian

2016-06-22

The objective of this study was to determine the effects of Tribulus terrestris L. (TT) saponins on exercise performance and the underlying mechanisms. A rat overtraining model was established and animals were treated with TT extracts (120 mg/kg body mass) 30 min before each training session. Serum levels of testosterone and corticosterone and levels of androgen receptor (AR) and insulin growth factor-1 receptor (IGF-1R) in the liver, gastrocnemius, and soleus were determined by ELISA and Western blot. Treatment of rats with TT saponins significantly improved the performance of the overtraining rats, reflected by the extension of time to exhaustion, with a concomitant increase in body mass, relative mass, and protein levels of gastrocnemius. Overtraining alone induced a significant decrease in the serum level of testosterone. In contrast, treatment with TT saponins dramatically increased the serum level of testosterone in overtraining rats to about 150% of control and 216% of overtraining groups, respectively. In addition, TT saponins resulted in a further significant increase in AR in gastrocnemius and significantly suppressed the overtraining-induced increase in IGF-1R in the liver. These results indicated that TT saponins increased performance, body mass, and gastrocnemius mass of rats undergoing overtraining, which might be attributed to the changes in androgen-AR axis and IGF-1R signaling.

Evaluation of left ventricular performance during supine exercise by transoesophageal M-mode echocardiography in normal subjects.

PubMed Central

Matsumoto, M; Hanrath, P; Kremer, P; Tams, C; Langenstein, B A; Schlüter, M; Weiter, R; Bleifeld, W

1982-01-01

In order to evaluate left ventricular function during dynamic exercise transoesophageal M-mode recordings of the left ventricle were carried out with a newly developed transducer gastroscope system. Twelve healthy subjects performed a graded supine bicycle exercise test. Stable and good quality images of the left ventricle at rest and during exercise at different steps up to a maximum workload of 100 watts were obtained in all patients. Isotonic maximum exercise resulted in a significant increase in fractional shortening of the left ventricle, peak shortening rate, and peak lengthening rate of the left ventricular minor axis. Left ventricular end-diastolic dimension decreased significantly. With increasing workload the pressure rate product increased significantly. It is concluded that transoesophageal M-mode echocardiography is a useful method of evaluating left ventricular performance during dynamic exercise. Images PMID:7082515

The effect of heavy- vs. light-load jump squats on the development of strength, power, and speed.

PubMed

McBride, Jeffrey M; Triplett-McBride, Travis; Davie, Allan; Newton, Robert U

2002-02-01

The purpose of this investigation was to examine the effect of an 8-week training program with heavy- vs. light-load jump squats on various physical performance measures and electromyography (EMG). Twenty-six athletic men with varying levels of resistance training experience performed sessions of jump squats with either 30% (JS30, n = 9) or 80% (JS80, n = 10) of their one repetition maximum in the squat (1RM) or served as a control (C, n = 7). An agility test, 20-m sprint, and jump squats with 30% (30J), 55% (55J), and 80% (80J) of their 1RM were performed before and after training. Peak force, peak velocity (PV), peak power (PP), jump height, and average EMG (concentric phase) were calculated for the jumps. There were significant increases in PP and PV in the 30J, 55J, and 80J for the JS30 group (p

The Effects of Assertive Training on Performance in Highly Anxious Adolescents.

ERIC Educational Resources Information Center

Wehr, Sara H.; Kaufman, Melvin E.

1987-01-01

Investigated the effects of assertive training on measures of assertiveness, state anxiety, and mathematics performance in highly anxious ninth graders (N=96). Found that assertive training resulted in increased assertiveness and decreased state anxiety, with no significant effect on mathematics performance, and no significant effect due to sex.…

Effect of stretching program in an industrial workplace on hamstring flexibility and sagittal spinal posture of adult women workers: a randomized controlled trial.

PubMed

Muyor, José M; López-Miñarro, Pedro A; Casimiro, Antonio J

2012-01-01

To determine the effect of a stretching program performed in the workplace on the hamstring muscle extensibility and sagittal spinal posture of adult women. Fifty-eight adult women volunteers (mean age of 44.23 ± 8.87 years) from a private fruit and vegetable company were randomly assigned to experimental (n=27) or control (n=31) groups. The experimental group performed three exercises of hamstrings stretching of 20 seconds per exercise, three sessions a week for a period of 12 weeks. The control group did not participate in any hamstring stretching program. Hamstring flexibility was evaluated through the passive straight leg raise test and toe-touch test, performed both before and after the stretching program. Thoracic and lumbar curvatures and pelvic inclination were measured in relaxed standing and toe-touch test with a Spinal Mouse. Significant increases (p < 0.01) in toe-touch score and straight leg raise angle (in both legs) were found in the experimental group during post-test, while the control group showed a non-significant decrease for both toe-touch score and straight leg raise test. A significant decrease in thoracic curve and significant increase in pelvic inclination were found in the toe-touch test for the experimental group (p <0.05). However, no significant changes were found in standing posture for any group. Hamstring stretching exercises performed in the working place are effective for increasing hamstring muscle extensibility. This increase generates a more aligned thoracic curve and more anterior pelvic inclination when maximal trunk flexion is performed.

Performance Enhancement Using Selective Reinforcement for Metallic Single- and Multi-Pin Loaded Holes

NASA Technical Reports Server (NTRS)

Farley, Gary L.; Seshadri, Banavara R.

2005-01-01

An analysis based investigation of aluminum with metal matrix composite selectively reinforced single- and multi-hole specimens was performed and their results compared with results from geometrically comparable non-reinforced specimens. All reinforced specimens exhibited a significant increase in performance. Performance increase of up to 170 percent was achieved. Specimen failure modes were consistent with results from reinforced polymeric matrix composite specimens. Localized reinforcement application (circular) proved as effective as a broader area (strip) reinforcement. Also, selective reinforcement is an excellent method of increasing the performance of multi-hole specimens.

Is a Responsive Default Mode Network Required for Successful Working Memory Task Performance?

PubMed

Čeko, Marta; Gracely, John L; Fitzcharles, Mary-Ann; Seminowicz, David A; Schweinhardt, Petra; Bushnell, M Catherine

2015-08-19

In studies of cognitive processing using tasks with externally directed attention, regions showing increased (external-task-positive) and decreased or "negative" [default-mode network (DMN)] fMRI responses during task performance are dynamically responsive to increasing task difficulty. Responsiveness (modulation of fMRI signal by increasing load) has been linked directly to successful cognitive task performance in external-task-positive regions but not in DMN regions. To investigate whether a responsive DMN is required for successful cognitive performance, we compared healthy human subjects (n = 23) with individuals shown to have decreased DMN engagement (chronic pain patients, n = 28). Subjects performed a multilevel working-memory task (N-back) during fMRI. If a responsive DMN is required for successful performance, patients having reduced DMN responsiveness should show worsened performance; if performance is not reduced, their brains should show compensatory activation in external-task-positive regions or elsewhere. All subjects showed decreased accuracy and increased reaction times with increasing task level, with no significant group differences on either measure at any level. Patients had significantly reduced negative fMRI response (deactivation) of DMN regions (posterior cingulate/precuneus, medial prefrontal cortex). Controls showed expected modulation of DMN deactivation with increasing task difficulty. Patients showed significantly reduced modulation of DMN deactivation by task difficulty, despite their successful task performance. We found no evidence of compensatory neural recruitment in external-task-positive regions or elsewhere. Individual responsiveness of the external-task-positive ventrolateral prefrontal cortex, but not of DMN regions, correlated with task accuracy. These findings suggest that a responsive DMN may not be required for successful cognitive performance; a responsive external-task-positive network may be sufficient. We studied the relationship between responsiveness of the brain to increasing task demand and successful cognitive performance, using chronic pain patients as a probe. fMRI working memory studies show that two main cognitive networks ["external-task positive" and "default-mode network" (DMN)] are responsive to increasing task difficulty. The responsiveness of both of these brain networks is suggested to be required for successful task performance. The responsiveness of external-task-positive regions has been linked directly to successful cognitive task performance, as we also show here. However, pain patients show decreased engagement and responsiveness of the DMN but can perform a working memory task as well as healthy subjects, without demonstrable compensatory neural recruitment. Therefore, a responsive DMN might not be needed for successful cognitive performance. Copyright © 2015 the authors 0270-6474/15/3511596-11$15.00/0.

The effects of growth hormone on body composition and physical performance in recreational athletes: a randomized trial.

PubMed

Meinhardt, Udo; Nelson, Anne E; Hansen, Jennifer L; Birzniece, Vita; Clifford, David; Leung, Kin-Chuen; Graham, Kenneth; Ho, Ken K Y

2010-05-04

Growth hormone is widely abused by athletes, frequently with androgenic steroids. Its effects on performance are unclear. To determine the effect of growth hormone alone or with testosterone on body composition and measures of performance. Randomized, placebo-controlled, blinded study of 8 weeks of treatment followed by a 6-week washout period. Randomization was computer-generated with concealed allocation. (Australian-New Zealand Clinical Trials Registry registration number: ACTRN012605000508673) Clinical research facility in Sydney, Australia. 96 recreationally trained athletes (63 men and 33 women) with a mean age of 27.9 years (SD, 5.7). Men were randomly assigned to receive placebo, growth hormone (2 mg/d subcutaneously), testosterone (250 mg/wk intramuscularly), or combined treatments. Women were randomly assigned to receive either placebo or growth hormone (2 mg/d). Body composition variables (fat mass, lean body mass, extracellular water mass, and body cell mass) and physical performance variables (endurance [maximum oxygen consumption], strength [dead lift], power [jump height], and sprint capacity [Wingate value]). Body cell mass was correlated with all measures of performance at baseline. Growth hormone significantly reduced fat mass, increased lean body mass through an increase in extracellular water, and increased body cell mass in men when coadministered with testosterone. Growth hormone significantly increased sprint capacity, by 0.71 kJ (95% CI, 0.1 to 1.3 kJ; relative increase, 3.9% [CI, 0.0% to 7.7%]) in men and women combined and by 1.7 kJ (CI, 0.5 to 3.0 kJ; relative increase, 8.3% [CI, 3.0% to 13.6%]) when coadministered with testosterone to men; other performance measures did not significantly change. The increase in sprint capacity was not maintained 6 weeks after discontinuation of the drug. Growth hormone dosage may have been lower than that used covertly by competitive athletes. The athletic significance of the observed improvements in sprint capacity is unclear, and the study was too small to draw conclusions about safety. Growth hormone supplementation influenced body composition and increased sprint capacity when administered alone and in combination with testosterone. The World Anti-Doping Agency.

Effect of heating system using a geothermal heat pump on the production performance and housing environment of broiler chickens.

PubMed

Choi, H C; Salim, H M; Akter, N; Na, J C; Kang, H K; Kim, M J; Kim, D W; Bang, H T; Chae, H S; Suh, O S

2012-02-01

A geothermal heat pump (GHP) is a potential heat source for the economic heating of broiler houses with optimum production performance. An investigation was conducted to evaluate the effect of a heating system using a GHP on production performance and housing environment of broiler chickens. A comparative analysis was also performed between the GHP system and a conventional heating system that used diesel for fuel. In total, 34,000 one-day-old straight run broiler chicks were assigned to 2 broiler houses with 5 replicates in each (3,400 birds/replicate pen) for 35 d. Oxygen(,) CO(2), and NH(3) concentrations in the broiler house, energy consumption and cost of heating, and production performance of broilers were evaluated. Results showed that the final BW gain significantly (P < 0.05) increased when chicks were reared in the GHP broiler house compared with that of chicks reared in the conventional broiler house (1.73 vs. 1.62 kg/bird). The heating system did not affect the mortality of chicks during the first 4 wk of the experimental period, but the mortality markedly increased in the conventional broiler house during the last wk of the experiment. Oxygen content in the broiler house during the experimental period was not affected by the heating system, but the CO(2) and NH(3) contents significantly increased (P < 0.05) in the conventional broiler house compared with those in the GHP house. Fuel consumption was significantly reduced (P < 0.05) and electricity consumption significantly increased (P < 0.05) in the GHP house compared with the consumption in the conventional house during the experiment. The total energy cost of heating the GHP house was significantly lower (P < 0.05) compared with that of the conventional house. It is concluded that a GHP system could increase the production performance of broiler chicks due to increased inside air quality of the broiler house. The GHP system had lower CO(2) and NH(3) emissions with lower energy cost than the conventional heating system for broiler chickens.

Allocation of healthcare dollars: analysis of nonneonatal circumcisions in Florida.

PubMed

Gutwein, Luke G; Alvarez, Juan F; Gutwein, Jenny L; Kays, David W; Islam, Saleem

2013-09-01

Circumcision remains a controversial operation. Most procedures are performed in the neonatal period and avoid general anesthesia. Legislation driven by policy statements from the American Academy of Pediatrics led to significant changes in circumcisions in Florida with a shift to nonneonatal procedures as a result of costs. We sought to study the prevalence and financial implications of nonneonatal circumcisions in Florida. A retrospective population study was performed using the Florida Agency for Health Care Administration outpatient procedure database. We queried for patients 0 to 17 years of age undergoing circumcision between 2003 and 2008. Demographics, charges, and insurance status were analyzed. From 2003 to 2008, 31,741 outpatient circumcisions were performed. Publicly funded circumcisions accounted for 17,537 charging the state $6,263 on average for each circumcision at an expense of $111.8 million for the 5-year time period analyzed. Publicly funded circumcision procedures increased more than sixfold (P < 0.0001) than those covered by private insurance. Black circumcision procedures increased 77.3 per cent, whereas white circumcisions increased 28.7 per cent. There has been a significant increase in the number of nonneonatal circumcisions performed. This has resulted in an increase in economic health care. Public funding of neonatal circumcision could result in significant cost savings and avoid potential complications of general anesthesia.

The green peach aphid Myzus persicae perform better on pre-infested Chinese cabbage Brassica pekinensis by enhancing host plant nutritional quality

PubMed Central

Cao, He-He; Liu, Hui-Ru; Zhang, Zhan-Feng; Liu, Tong-Xian

2016-01-01

The green peach aphid, Myzus persicae Sulzer, is a notorious pest on vegetables, which often aggregates in high densities on crop leaves. In this study, we investigated whether M. persicae could suppress the resistance level of Chinese cabbage Brassica pekinensis. M. persicae performed better in terms of weight gain (~33% increase) and population growth (~110% increase) when feeding on previously infested (pre-infested) Chinese cabbage compared with those on non-infested plants. However, when given a choice, 64% of the aphids preferred to settle on non-infested leaves, while 29% of aphids chose pre-infested leaves that had a 2.9 times higher concentration of glucosinolates. Aphid feeding significantly enhanced the amino acid:sugar ratio of phloem sap and the absolute amino acid concentration in plant leaves. Aphid infestation significantly increased the expression levels of salicylic acid (SA) marker genes, while it had marginal effects on the expression of jasmonate marker genes. Exogenously applied SA or methyl jasmonate had no significant effects on M. persicae performance, although these chemicals increased glucosinolates concentration in plant leaves. M. persicae infestation increase amino acid:sugar ratio and activate plant defenses, but aphid performed better on pre-infested plants, suggesting that both nutrition and toxics should be considered in insect-plant interaction. PMID:26905564

Evolution of Determinant Factors of Repeated Sprint Ability.

PubMed

Pareja-Blanco, Fernando; Suarez-Arrones, Luis; Rodríguez-Rosell, David; López-Segovia, Manuel; Jiménez-Reyes, Pedro; Bachero-Mena, Beatriz; González-Badillo, Juan José

2016-12-01

The aim of this study was to investigate the changes in the relationships between repeated sprint ability (RSA) and anthropometric measures as well as fitness qualities in soccer players. Twenty-one professional soccer players performed several anthropometric and physical tests including countermovement vertical jumps (CMJs), a straight-line 30 m sprint (T30), an RSA test (6 x 20 + 20 m with 20 s recovery), a progressive isoinertial loading test in a full squat, a Yo-Yo Intermittent Recovery Test Level-1 (YYIRT-1) and a 20 m shuttle run test (20mSRT). The mean (RSAmean), the fastest (RSAbest), each single sprint time, and the percentage in a sprint decrease (%Dec) in the RSA test were calculated. RSAbest correlated significantly with RSAmean (r = .82) and with all single sprints (p < 0.05), showing a downward trend as the number of sprints performed increased. No significant relationship was observed between the %Dec and RSA performance. CMJs and the T30 also showed a correlation with RSA performance, whereas lower limb strength did not show any relationship with RSA performance. RSAmean showed significant (p < 0.05) relationships with body mass (r = .44), adiposity (r = .59) and the YYIRT-1 (r = -.62), increasing as the number of repeated sprints increased. The 20mSRT showed minimal relationships with RSA performance. In conclusion, maximal sprint capacity seems to be relevant for the RSA performance, mainly in the first sprints. However, high intermittent endurance capacity and low adiposity might help enhance the RSA performance when increasing the number of repeated sprints.

Evolution of Determinant Factors of Repeated Sprint Ability

PubMed Central

Suarez-Arrones, Luis; Rodríguez-Rosell, David; López-Segovia, Manuel; Jiménez-Reyes, Pedro; Bachero-Mena, Beatriz; González-Badillo, Juan José

2016-01-01

Abstract The aim of this study was to investigate the changes in the relationships between repeated sprint ability (RSA) and anthropometric measures as well as fitness qualities in soccer players. Twenty-one professional soccer players performed several anthropometric and physical tests including countermovement vertical jumps (CMJs), a straight-line 30 m sprint (T30), an RSA test (6 x 20 + 20 m with 20 s recovery), a progressive isoinertial loading test in a full squat, a Yo-Yo Intermittent Recovery Test Level-1 (YYIRT-1) and a 20 m shuttle run test (20mSRT). The mean (RSAmean), the fastest (RSAbest), each single sprint time, and the percentage in a sprint decrease (%Dec) in the RSA test were calculated. RSAbest correlated significantly with RSAmean (r = .82) and with all single sprints (p < 0.05), showing a downward trend as the number of sprints performed increased. No significant relationship was observed between the %Dec and RSA performance. CMJs and the T30 also showed a correlation with RSA performance, whereas lower limb strength did not show any relationship with RSA performance. RSAmean showed significant (p < 0.05) relationships with body mass (r = .44), adiposity (r = .59) and the YYIRT-1 (r = -.62), increasing as the number of repeated sprints increased. The 20mSRT showed minimal relationships with RSA performance. In conclusion, maximal sprint capacity seems to be relevant for the RSA performance, mainly in the first sprints. However, high intermittent endurance capacity and low adiposity might help enhance the RSA performance when increasing the number of repeated sprints. PMID:28031763

Comparative cross-sectional study of masticatory performance and mastication predominance for patients with missing posterior teeth.

PubMed

Iwashita, Hayato; Tsukiyama, Yoshihiro; Kori, Hidehiro; Kuwatsuru, Rika; Yamasaki, Yo; Koyano, Kiyoshi

2014-10-01

Missing posterior teeth can decrease masticatory function and cause horizontal mastication deviation, i.e., mastication predominance. Mastication predominance may lead to abnormal tooth attrition and temporomandibular disorders. This study evaluated masticatory performance and mastication predominance in patients with missing posterior teeth to investigate effects of missing posterior teeth on masticatory performance and mastication predominance. Thirty volunteers with normal dentition (control group), 30 patients with unilateral missing posterior teeth (unilateral group), and 23 patients with bilateral missing posterior teeth (bilateral group) participated. Gummy jellies were used to evaluate participants' masticatory performance, and electromyography was used to assess the degree of mastication predominance. Chewing gums, gummy jellies, and peanuts were used as foods of various hardnesses for evaluating mastication predominance. Compared with the control group, masticatory performance did not differ in the unilateral group but was significantly decreased in the bilateral group. With chewing gum and gummy jellies, the degree of mastication predominance was significantly increased in both unilateral and bilateral groups than the control group. With peanuts, the degree of mastication predominance was significantly increased in the unilateral group than the control group. Although masticatory performance was not decreased in the unilateral group, the degree of mastication predominance was increased. Decreased masticatory performance was observed in the bilateral group, and for foods with normal hardness and soft foods, the degree of mastication predominance was increased. These results suggested that mastication predominance should be considered in the recovery of masticatory performance in patients with missing posterior teeth. Copyright © 2014 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

Daytime light exposure: effects on biomarkers, measures of alertness, and performance.

PubMed

Sahin, Levent; Wood, Brittany M; Plitnick, Barbara; Figueiro, Mariana G

2014-11-01

Light can elicit an alerting response in humans, independent from acute melatonin suppression. Recent studies have shown that red light significantly increases daytime and nighttime alertness. The main goal of the present study was to further investigate the effects of daytime light exposure on performance, biomarkers and measures of alertness. It was hypothesized that, compared to remaining in dim light, daytime exposure to narrowband long-wavelength (red) light or polychromatic (2568K) light would induce greater alertness and shorter response times. Thirteen subjects experienced three lighting conditions: dim light (<5lux), red light (λmax=631nm, 213lux, 1.1W/m(2)), and white light (2568K, 361lux, 1.1W/m(2)). The presentation order of the lighting conditions was counterbalanced across the participants and each participant saw a different lighting condition each week. Our results demonstrate, for the first time, that red light can increase short-term performance as shown by the significant (p<0.05) reduced response time and higher throughput in performance tests during the daytime. There was a significant decrease (p<0.05) in alpha power and alpha-theta power after exposure to the white light, but this alerting effect did not translate to better performance. Alpha power was significantly reduced after red light exposure in the middle of the afternoon. There was no significant effect of light on cortisol and alpha amylase. The present results suggest that red light can be used to increase daytime performance. Copyright © 2014 Elsevier B.V. All rights reserved.

Actoprotective effect of ginseng: improving mental and physical performance

PubMed Central

Oliynyk, Sergiy; Oh, Seikwan

2013-01-01

Actoprotectors are preparations that increase the mental performance and enhance body stability against physical loads without increasing oxygen consumption. Actoprotectors are regarded as a subclass of adaptogens that hold a significant capacity to increase physical performance. The focus of this article is studying adaptogen herbs of genus Panax (P. ginseng in particular) and their capabilities as actoprotectors. Some animal experiments and human studies about actoprotective properties of genus Panax attest that P. ginseng (administered as an extract) significantly increased the physical and intellectual work capacities, and the data provided suggests that ginseng is a natural source of actoprotectors. Preparations of ginseng can be regarded as potential actoprotectors which give way to further research of its influence on physical and mental work capacity, endurance and restoration after exhaustive physical loads while compared with reference actoprotectors. PMID:23717168

Elastic Bands in Combination With Free Weights in Strength Training: Neuromuscular Effects.

PubMed

Andersen, Vidar; Fimland, Marius S; Kolnes, Maria K; Saeterbakken, Atle H

2015-10-01

This study compared the effects of a variable vs. a constant lower limb resistance training program on muscle strength, muscle activation, and ballistic muscle performance at different knee angles. Thirty-two females were randomized to a constant resistance training free-weight group (FWG) or a variable resistance training group using free weights in combination with elastic bands (EBG). Two variations of the squat exercise (back squat and split) were performed 2 days per week for 10 weeks. Knee extensor maximal voluntary isometric contraction (MVC) and countermovement jump were assessed at knee angles of 60, 90, and 120° before and after the intervention. During the MVCs, muscle activation of the superficial knee extensor muscles was measured using surface electromyography. The FWG increased their MVCs at 60 and 90° (24 and 15%, respectively), whereas the EBG only increased significantly at 60° (15%). The FWG increased their jump height significantly at all angles (12-16%), whereas the EBG only improved significantly at 60 and 90° (15 and 10%, respectively). Both groups improved their 6-repetition maximum free-weight squat performance (EBG: 25% and FWG: 23%). There were no significant changes in muscle activation. In conclusion, constant and variable resistance training provided similar increases in dynamic and isometric strength, and ballistic muscle performance, albeit most consistently for the group training only with free weights.

Do absorption and realistic distraction influence performance of component task surgical procedure?

PubMed

Pluyter, Jon R; Buzink, Sonja N; Rutkowski, Anne-F; Jakimowicz, Jack J

2010-04-01

Surgeons perform complex tasks while exposed to multiple distracting sources that may increase stress in the operating room (e.g., music, conversation, and unadapted use of sophisticated technologies). This study aimed to examine whether such realistic social and technological distracting conditions may influence surgical performance. Twelve medical interns performed a laparoscopic cholecystectomy task with the Xitact LC 3.0 virtual reality simulator under distracting conditions (exposure to music, conversation, and nonoptimal handling of the laparoscope) versus nondistracting conditions (control condition) as part of a 2 x 2 within-subject experimental design. Under distracting conditions, the medical interns showed a significant decline in task performance (overall task score, task errors, and operating time) and significantly increased levels of irritation toward both the assistant handling the laparoscope in a nonoptimal way and the sources of social distraction. Furthermore, individual differences in cognitive style (i.e., cognitive absorption and need for cognition) significantly influenced the levels of irritation experienced by the medical interns. The results suggest careful evaluation of the social and technological sources of distraction in the operation room to reduce irritation for the surgeon and provision of proper preclinical laparoscope navigation training to increase security for the patient.

Improving resident performance on standardized assessments of medical knowledge: a retrospective analysis of interventions correlated to American Board of Surgery In-Service Training Examination performance.

PubMed

Buckley, Elaine Jayne; Markwell, Stephen; Farr, Debb; Sanfey, Hilary; Mellinger, John

2015-10-01

American Board of Surgery In-Service Training Examination (ABSITE) scores are used to assess individual progress and predict board pass rates. We reviewed strategies to enhance ABSITE performance and their impact within a surgery residency. Several interventions were introduced from 2010 to 2014. A retrospective review was undertaken evaluating these and correlating them to ABSITE performance. Analyses of variance and linear trends were performed for ABSITE, United States Medical Licensing Examination (USMLEs), mock oral, and mock ABSITE scores followed by post hoc analyses if significant. Results were correlated with core curricular changes. ABSITE mean percentile increased 34% in 4 years with significant performance improvement and increasing linear trends in postgraduate year (PGY)1 and PGY4 ABSITE scores. Mock ABSITE introduction correlated to significant improvement in ABSITE scores for PGY4 and PGY5. Mock oral introduction correlated with significant improvement in PGY1 and PGY3. Our study demonstrates an improvement in mean program ABSITE percentiles correlating with multiple interventions. Similar strategies may be useful for other programs. Copyright © 2015 Elsevier Inc. All rights reserved.

Performance of an Axisymmetric Rocket Based Combined Cycle Engine During Rocket Only Operation Using Linear Regression Analysis

NASA Technical Reports Server (NTRS)

Smith, Timothy D.; Steffen, Christopher J., Jr.; Yungster, Shaye; Keller, Dennis J.

1998-01-01

The all rocket mode of operation is shown to be a critical factor in the overall performance of a rocket based combined cycle (RBCC) vehicle. An axisymmetric RBCC engine was used to determine specific impulse efficiency values based upon both full flow and gas generator configurations. Design of experiments methodology was used to construct a test matrix and multiple linear regression analysis was used to build parametric models. The main parameters investigated in this study were: rocket chamber pressure, rocket exit area ratio, injected secondary flow, mixer-ejector inlet area, mixer-ejector area ratio, and mixer-ejector length-to-inlet diameter ratio. A perfect gas computational fluid dynamics analysis, using both the Spalart-Allmaras and k-omega turbulence models, was performed with the NPARC code to obtain values of vacuum specific impulse. Results from the multiple linear regression analysis showed that for both the full flow and gas generator configurations increasing mixer-ejector area ratio and rocket area ratio increase performance, while increasing mixer-ejector inlet area ratio and mixer-ejector length-to-diameter ratio decrease performance. Increasing injected secondary flow increased performance for the gas generator analysis, but was not statistically significant for the full flow analysis. Chamber pressure was found to be not statistically significant.

New stimulation pattern design to improve P300-based matrix speller performance at high flash rate

NASA Astrophysics Data System (ADS)

Polprasert, Chantri; Kukieattikool, Pratana; Demeechai, Tanee; Ritcey, James A.; Siwamogsatham, Siwaruk

2013-06-01

Objective. We propose a new stimulation pattern design for the P300-based matrix speller aimed at increasing the minimum target-to-target interval (TTI). Approach. Inspired by the simplicity and strong performance of the conventional row-column (RC) stimulation, the proposed stimulation is obtained by modifying the RC stimulation through alternating row and column flashes which are selected based on the proposed design rules. The second flash of the double-flash components is then delayed for a number of flashing instants to increase the minimum TTI. The trade-off inherited in this approach is the reduced randomness within the stimulation pattern. Main results. We test the proposed stimulation pattern and compare its performance in terms of selection accuracy, raw and practical bit rates with the conventional RC flashing paradigm over several flash rates. By increasing the minimum TTI within the stimulation sequence, the proposed stimulation has more event-related potentials that can be identified compared to that of the conventional RC stimulations, as the flash rate increases. This leads to significant performance improvement in terms of the letter selection accuracy, the raw and practical bit rates over the conventional RC stimulation. Significance. These studies demonstrate that significant performance improvement over the RC stimulation is obtained without additional testing or training samples to compensate for low P300 amplitude at high flash rate. We show that our proposed stimulation is more robust to reduced signal strength due to the increased flash rate than the RC stimulation.

Status of Teacher Performance Pay Programs across the United States. Information Capsule. Volume 1103

ERIC Educational Resources Information Center

Blazer, Christie

2011-01-01

An increasing number of states and school districts across the country are tying teacher pay to student performance. A recent RAND Education study found that nationwide spending on teacher performance pay increased from $99 million in 2006 to $439 million in 2010. However, many states and school districts face significant hurdles when they attempt…

Performance assessment through pre- and post-training evaluation of continuing medical education courses in prevention and management of cardio-vascular diseases in primary health care facilities of Armenia.

PubMed

Khachatryan, Lilit; Balalian, Arin

2013-12-01

To assess the difference of pre- and post-training performance evaluation of continuing medical education (CME) courses in cardio-vascular diseases (CVD) management among physicians at primary health care facilities of Armenian regions we conducted an evaluation survey. 212 medical records were surveyed on assessment of performance before and after the training courses through a self-employed structured questionnaire. Analysis of survey revealed statistically significant differences (p < 0.05) in a number of variables: threefold increased recording of lipids and body mass index (p = 0.001); moderate increased recording of comorbidities and aspirin prescription (p < 0.012); eightfold increased recording of dyslipidemia management plan, twofold increased recording for CVD management plan and fivefold increased recording for CVD absolute risk (p = 0.000). Missing records of electrocardiography and urine/creatinine analyses decreased statistically significantly (p < 0.05). Statistically significant decrease was observed in prescription of thiazides and angiotensin receptor blockers/angiotensin converting enzyme inhibitors (p < 0.005), while prescription of statins and statins with diet for dyslipidemia management showed increased recording (p < 0.05). Similarly, we observed increased records for counseling of rehabilitation physical activity (p = 0.006). In this survey most differences in pre- and post-evaluation of performance assessment may be explained by improved and interactive training modes, more advanced methods of demonstration of modeling. Current findings may serve a basis for future planning of CME courses for physicians of remote areas facing challenges in upgrading their knowledge, as well as expand the experience of performance assessment along with evaluation of knowledge scores.

Effects of increasing and decreasing physiological arousal on anticipation timing performance during competition and practice.

PubMed

Duncan, Michael J; Smith, Mike; Bryant, Elizabeth; Eyre, Emma; Cook, Kathryn; Hankey, Joanne; Tallis, Jason; Clarke, Neil; Jones, Marc V

2016-01-01

The aim of this study was to investigate if the effects of changes in physiological arousal on timing performance can be accurately predicted by the catastrophe model. Eighteen young adults (8 males, 10 females) volunteered to participate in the study following ethical approval. After familiarisation, coincidence anticipation was measured using the Bassin Anticipation Timer under four incremental exercise conditions: Increasing exercise intensity and low cognitive anxiety, increasing exercise intensity and high cognitive anxiety, decreasing exercise intensity and low cognitive anxiety and decreasing exercise intensity and high cognitive anxiety. Incremental exercise was performed on a treadmill at intensities of 30%, 50%, 70% and 90% heart rate reserve (HRR) respectively. Ratings of cognitive anxiety were taken at each intensity using the Mental Readiness Form 3 (MRF3) followed by performance of coincidence anticipation trials at speeds of 3 and 8 mph. Results indicated significant condition × intensity interactions for absolute error (AE; p = .0001) and MRF cognitive anxiety intensity scores (p = .05). Post hoc analysis indicated that there were no statistically significant differences in AE across exercise intensities in low-cognitive anxiety conditions. In high-cognitive anxiety conditions, timing performance AE was significantly poorer and cognitive anxiety higher at 90% HRR, compared to the other exercise intensities. There was no difference in timing responses at 90% HRR during competitive trials, irrespective of whether exercise intensity was increasing or decreasing. This study suggests that anticipation timing performance is negatively affected when physiological arousal and cognitive anxiety are high.

Changes in Brain Network Efficiency and Working Memory Performance in Aging

PubMed Central

Stanley, Matthew L.; Simpson, Sean L.; Dagenbach, Dale; Lyday, Robert G.; Burdette, Jonathan H.; Laurienti, Paul J.

2015-01-01

Working memory is a complex psychological construct referring to the temporary storage and active processing of information. We used functional connectivity brain network metrics quantifying local and global efficiency of information transfer for predicting individual variability in working memory performance on an n-back task in both young (n = 14) and older (n = 15) adults. Individual differences in both local and global efficiency during the working memory task were significant predictors of working memory performance in addition to age (and an interaction between age and global efficiency). Decreases in local efficiency during the working memory task were associated with better working memory performance in both age cohorts. In contrast, increases in global efficiency were associated with much better working performance for young participants; however, increases in global efficiency were associated with a slight decrease in working memory performance for older participants. Individual differences in local and global efficiency during resting-state sessions were not significant predictors of working memory performance. Significant group whole-brain functional network decreases in local efficiency also were observed during the working memory task compared to rest, whereas no significant differences were observed in network global efficiency. These results are discussed in relation to recently developed models of age-related differences in working memory. PMID:25875001

Changes in brain network efficiency and working memory performance in aging.

PubMed

Stanley, Matthew L; Simpson, Sean L; Dagenbach, Dale; Lyday, Robert G; Burdette, Jonathan H; Laurienti, Paul J

2015-01-01

Working memory is a complex psychological construct referring to the temporary storage and active processing of information. We used functional connectivity brain network metrics quantifying local and global efficiency of information transfer for predicting individual variability in working memory performance on an n-back task in both young (n = 14) and older (n = 15) adults. Individual differences in both local and global efficiency during the working memory task were significant predictors of working memory performance in addition to age (and an interaction between age and global efficiency). Decreases in local efficiency during the working memory task were associated with better working memory performance in both age cohorts. In contrast, increases in global efficiency were associated with much better working performance for young participants; however, increases in global efficiency were associated with a slight decrease in working memory performance for older participants. Individual differences in local and global efficiency during resting-state sessions were not significant predictors of working memory performance. Significant group whole-brain functional network decreases in local efficiency also were observed during the working memory task compared to rest, whereas no significant differences were observed in network global efficiency. These results are discussed in relation to recently developed models of age-related differences in working memory.

Learning to Improve: Using Writing to Increase Critical Thinking Performance in General Education Biology

PubMed Central

Kurtz, Martha J.

2007-01-01

Increasingly, national stakeholders express concern that U.S. college graduates cannot adequately solve problems and think critically. As a set of cognitive abilities, critical thinking skills provide students with tangible academic, personal, and professional benefits that may ultimately address these concerns. As an instructional method, writing has long been perceived as a way to improve critical thinking. In the current study, the researchers compared critical thinking performance of students who experienced a laboratory writing treatment with those who experienced traditional quiz-based laboratory in a general education biology course. The effects of writing were determined within the context of multiple covariables. Results indicated that the writing group significantly improved critical thinking skills whereas the nonwriting group did not. Specifically, analysis and inference skills increased significantly in the writing group but not the nonwriting group. Writing students also showed greater gains in evaluation skills; however, these were not significant. In addition to writing, prior critical thinking skill and instructor significantly affected critical thinking performance, whereas other covariables such as gender, ethnicity, and age were not significant. With improved critical thinking skill, general education biology students will be better prepared to solve problems as engaged and productive citizens. PMID:17548876

Muscular power, neuromuscular activation, and performance in shot put athletes at preseason and at competition period.

PubMed

Kyriazis, Thomas A; Terzis, Gerasimos; Boudolos, Konstantinos; Georgiadis, Georgios

2009-09-01

The aim of this study was to investigate changes in shot put performance, muscular power, and neuromuscular activation of the lower extremities, between the preseason and the competition period, in skilled shot put athletes using the rotational technique. Shot put performance was assessed at the start of the pre-season period as well as after 12 weeks, at the competition period, in nine shot putters. Electromyographic (EMG) activity of the right vastus lateralis muscle was recorded during all shot put trials. Maximum squat strength (1RM) and mechanical parameters during the countermovement jump (CMJ) on a force platform were also determined at pre-season and at competition period. Shot put performance increased 4.7% (p < 0.05), while 1RM squat increased 6.5% (p < 0.025). EMG activity during the delivery phase was increased significantly (p < 0.025) after the training period. Shot put performance was significantly related with muscular power and takeoff velocity during the CMJ, at competition period (r = 0.66, p < 0.05 and 0.70, p < 0.05), but not with maximum vertical force. One RM squat was not related significantly with shot put performance. These results suggest that muscular power of the lower extremities is a better predictor of rotational shot put performance than absolute muscular strength in skilled athletes, at least during the competition period.

Growth performance and carcase quality in broiler chickens fed on bacterial protein grown on natural gas.

PubMed

Øverland, M; Schøyen, H F; Skrede, A

2010-10-01

1. The effects of increasing concentrations (0, 40, 80 or 120 g/kg) of bacterial protein meal (BPM) and bacterial protein autolysate (BPA) grown on natural gas on growth performance and carcase quality in broiler chickens were examined. 2. Adding BPM to diets reduced feed intake and improved gain: feed from 0 to 21 d and overall to 35 d, but did not significantly affect weight gain compared to the soybean meal based control diet. 3. Increasing concentrations of BPA significantly reduced growth rate, feed intake, gain: feed, carcase weight and dressing percentage, but significantly increased carcase dry matter, fat and energy content. 4. Adding BPM to diets had no effect on viscosity of diets and jejunal digesta, and minor effects on litter quality, whereas BPA increased the viscosity of diets and jejunal digesta, improved litter quality at 21 d, but decreased litter quality at 32 d. 5. To conclude, broiler chickens performed better on a BPM product with intact proteins than on an autolysate with ruptured cell walls and a high content of free amino acids and low molecular-weight peptides.

Cardiorespiratory, neuromuscular and kinematic responses to stationary running performed in water and on dry land.

PubMed

Alberton, Cristine Lima; Cadore, Eduardo Lusa; Pinto, Stephanie Santana; Tartaruga, Marcus Peikriszwili; da Silva, Eduardo Marczwski; Kruel, Luiz Fernando Martins

2011-06-01

The purpose of this study was to analyze the cardiorespiratory, neuromuscular and kinematic responses obtained during the stationary running in aquatic and dry land environments. Twelve women took part in the experimental protocol. Stationary running was performed for 4 min at three submaximal cadences and for 15 s at maximal velocity, with the collection of kinematic (peak hip angular velocity (AV)), cardiorespiratory (oxygen uptake (VO(2))) and neuromuscular variables (electromyographic (EMG) signal from the rectus femoris (RF), vastus lateralis (VL), semitendinosus (ST) and short head of the biceps femoris (BF) muscles) in land-based and water-based test protocols. Factorial ANOVA was used, with an alpha level of 0.05. AV was significantly higher when the exercise was performed on land, and became significantly higher as the execution cadence increased. Similarly, VO(2) was significantly higher in the land-based exercise and rose as cadence increased. With the increase in the submaximal execution cadences, there was no corresponding increase in the EMG signal from the VL, BF, RF and ST muscles in either environment, though such a significantly increase was seen between the submaximal cadences and the maximal velocity. Dry land presented significantly greater EMG signal responses for all muscles at the submaximal cadences, except for the ST muscle. However, at the maximal velocity, all the analyzed muscle groups showed similar responses in both environments. In summary, for both environments, cardiorespiratory responses can be maximized by increasing the submaximal cadences, while neuromuscular responses are only optimized by using maximal velocity.

Time taken as a determinant of advancement in Shotokan karate black-belt Heian kata performance.

PubMed

Layton, C; Avenell, L

1999-12-01

30 experienced black-belt subjects were individually timed on each of the five Heian kata. Significant relationships were found between years of training and increased performance time on all the kata and for four with age controlled. The multiple correlation was significant.

Significant Differences in Pediatric Psychotropic Side Effects: Implications for School Performance

ERIC Educational Resources Information Center

Kubiszyn, Thomas; Mire, Sarah; Dutt, Sonia; Papathopoulos, Katina; Burridge, Andrea Backsheider

2012-01-01

Some side effects (SEs) of increasingly prescribed psychotropic medications can impact student performance in school. SE risk varies, even among drugs from the same class (e.g., antidepressants). Knowing which SEs occur significantly more often than others may enable school psychologists to enhance collaborative risk-benefit analysis, medication…

The effect of lameness on the environmental performance of milk production by rotational grazing.

PubMed

Chen, Wenhao; White, Eoin; Holden, Nicholas M

2016-05-01

Dairy production leads to significant environmental impacts and increased production will only be feasible if the environmental performance at farm level permits a sustainable milk supply. Lameness is believed to become more prevalent and severe as herd sizes increase, and can significantly reduce milk output per cow while not influencing other attributes of the production system. The objective of this work was to quantify the effect of lameness on the environmental performance of a typical grazed grass dairy farm and evaluate the theoretical value of sensor-based real-time lameness management. Life cycle assessment was used to compare a typical baseline farm with scenarios assuming increased lameness severity and prevalence. It was found that lameness could increase the farm level global warming potential, acidification potential, eutrophication potential and fossil fuel depletion by 7-9%. As increased herd sizes will increase cow: handler ratio, this result was interpreted to suggest that the use of sensors and information and communication technology for lameness detection could improve management on dairy farms to reduce the adverse impact on environmental performance that is associated with lameness. Copyright © 2016 Elsevier Ltd. All rights reserved.

Association between the MTHFR C677T polymorphism and risk of cancer: evidence from 446 case-control studies.

PubMed

Xie, Shu-Zhe; Liu, Zhi-Zhong; Yu, Jun-hua; Liu, Li; Wang, Wei; Xie, Dao-Lin; Qin, Jiang-Bo

2015-11-01

Many molecular epidemiological studies have been performed to explore the association between MTHFR C677T polymorphism and cancer risk in diverse populations. However, the results were inconsistent. Hence, we performed a meta-analysis to investigate the association between cancer risk and MTHFR C677T (150,086 cases and 200,699 controls from 446 studies) polymorphism. Overall, significantly increased cancer risk was found when all eligible studies were pooled into the meta-analysis. In the further stratified and sensitivity analyses, significantly increased breast cancer risk was found in Asians and Indians, significantly decreased colon cancer risk was found, significantly decreased colorectal cancer risk was found in male population, significantly increased gastric cancer risk was found in Caucasians and Asians, significantly increased hepatocellular cancer risk was found in Asians, significantly decreased adult acute lymphoblastic leukemia (AALL) risk was found in Caucasians, significantly decreased childhood acute lymphoblastic leukemia (CALL) risk was found in Asians, and significantly increased multiple myeloma and NHL risk was found in Caucasians. In summary, this meta-analysis suggests that MTHFR C677T polymorphism is associated with increased breast cancer, gastric cancer, and hepatocellular cancer risk in Asians, is associated with increased gastric cancer, multiple myeloma, and NHL risk in Caucasians, is associated with decreased AALL risk in Caucasians, is associated with decreased CALL risk in Asians, is associated with increased breast cancer risk in Asians, is associated with decreased colon cancer risk, and is associated with decreased colorectal cancer risk in male population. Moreover, this meta-analysis also points out the importance of new studies, such as Asians of HNC, Asians of lung cancer, and Indians of breast cancer, because they had high heterogeneity in this meta-analysis (I(2) > 75%).

Effect of Progressive Volume-Based Overload During Plyometric Training on Explosive and Endurance Performance in Young Soccer Players.

PubMed

Ramírez-Campillo, Rodrigo; Henríquez-Olguín, Carlos; Burgos, Carlos; Andrade, David C; Zapata, Daniel; Martínez, Cristian; Álvarez, Cristian; Baez, Eduardo I; Castro-Sepúlveda, Mauricio; Peñailillo, Luis; Izquierdo, Mikel

2015-07-01

The purpose of the study was to compare the effects of progressive volume-based overload with constant volume-based overload on muscle explosive and endurance performance adaptations during a biweekly short-term (i.e., 6 weeks) plyometric training intervention in young soccer players. Three groups of young soccer players (age 13.0 ± 2.3 years) were divided into: control (CG; n = 8) and plyometric training with (PPT; n = 8) and without (NPPT; n = 8) a progressive increase in volume (i.e., 16 jumps per leg per week, with an initial volume of 80 jumps per leg each session). Bilateral and unilateral horizontal and vertical countermovement jump with arms (CMJA), 20-cm drop jump reactive strength index (RSI20), maximal kicking velocity (MKV), 10-m sprint, change of direction speed (CODS), and Yo-Yo intermittent recovery level 1 test (Yo-Yo IR1) were measured. Although both experimental groups significantly increased CMJA, RSI20, CODS, and endurance performance, only PPT showed a significant improvement in MKV and 10-m sprint time. In addition, only PPT showed a significantly higher performance improvement in jumping, MKV, and Yo-Yo IR1 compared with CG. Also, PPT showed higher meaningful improvement compared with NPPT in all (except 1) jump performance measures. Furthermore, although PPT involved a higher total volume compared with NPPT, training efficiency (i.e., percentage change in performance/total jump volume) was similar between groups. Our results show that PPT and NPPT ensured significant improvement in muscle explosive and endurance performance measures. However, a progressive increase in plyometric training volume seems more advantageous to induce soccer-specific performance improvements.

A comparative study of slow and fast suryanamaskar on physiological function

PubMed Central

Bhavanani, Ananda Balayogi; Udupa, Kaviraja; Madanmohan; Ravindra, PN

2011-01-01

Background: Numerous scientific studies have reported beneficial physiological changes after short- and long-term yoga training. Suryanamaskar (SN) is an integral part of modern yoga training and may be performed either in a slow or rapid manner. As there are few studies on SN, we conducted this study to determine the differential effect of 6 months training in the fast and slow versions. Materials and Methods: 42 school children in the age group of 12–16 years were randomly divided into two groups of 21 each. Group I and Group II received 6 months training in performance of slow suryanamaskar (SSN) and fast suryanamaskar (FSN), respectively. Results: Training in SSN produced a significant decrease in diastolic pressure. In contrast, training in FSN produced a significant increase in systolic pressure. Although there was a highly significant increase in isometric hand grip (IHG) strength and hand grip endurance (HGE) in both the groups, the increase in HGE in FSN group was significantly more than in SSN group. Pulmonary function tests showed improvements in both the groups though intergroup comparison showed no significance difference. Maximum inspiratory pressure (MIP) and maximum expiratory pressure increased significantly in both the groups with increase of MIP in FSN group being more significant than in SSN. Conclusion: The present study reports that SN has positive physiological benefits as evidenced by improvement of pulmonary function, respiratory pressures, hand grip strength and endurance, and resting cardiovascular parameters. It also demonstrates the differences between SN training when performed in a slow and fast manner, concluding that the effects of FSN are similar to physical aerobic exercises, whereas the effects of SSN are similar to those of yoga training. PMID:22022125

Effects of Plyometric Training on Muscle-Activation Strategies and Performance in Female Athletes

PubMed Central

Swanik, Kathleen A.; Swanik, C. Buz; Straub, Stephen J.

2004-01-01

Objective: To evaluate the effects of plyometric training on muscle-activation strategies and performance of the lower extremity during jumping exercises. Subjects: Twenty healthy National Collegiate Athletic Association Division I female athletes. Design and Setting: A pretest and posttest control group design was used. Experimental subjects performed plyometric exercises 2 times per week for 6 weeks. Measurements: We used surface electromyography to assess preparatory and reactive activity of the vastus medialis and vastus lateralis, medial and lateral hamstrings, and hip abductors and adductors. Vertical jump height and sprint speed were assessed with the VERTEC and infrared timing devices, respectively. Results: Multivariate analyses of variance revealed significant (P < .05) increases in firing of adductor muscles during the preparatory phase, with significant interactions for area, mean, and peak. A Tukey honestly significant difference post hoc analysis revealed significant increases in preparatory adductor area, mean, and peak for experimental group. A significant (P = .037) increase in preparatory adductor-to-abductor muscle coactivation in the experimental group was identified, as well as a trend (P = .053) toward reactive quadriceps-to- hamstring muscle coactivation in the experimental group. Pearson correlation coefficients revealed significant between-groups adaptations in muscle activity patterns pretest to posttest. Although not significant, experimental and control subjects had average increases of 5.8% and 2.0% in vertical jump height, respectively. Conclusions: The increased preparatory adductor activity and abductor-to-adductor coactivation represent preprogrammed motor strategies learned during the plyometric training. These data strongly support the role of hip-musculature activation strategies for dynamic restraint and control of lower extremity alignment at ground contact. Plyometric exercises should be incorporated into the training regimens of female athletes and may reduce the risk of injury by enhancing functional joint stability in the lower extremity. PMID:15085208

Effects of chewing gum on mood, learning, memory and performance of an intelligence test.

PubMed

Smith, Andrew

2009-04-01

Recent research suggests that chewing gum may increase alertness and lead to changes in cognitive performance. The present study examined effects of chewing gum on these functions within the context of a single study. This study had four main aims. The first was to examine whether chewing gum improved learning and memory of information in a story. The second aim was to determine whether chewing gum improved test performance on a validated intellectual task (the Alice Heim task). A third aim was to determine whether chewing gum improved performance on short memory tasks (immediate and delayed recall of a list of words, delayed recognition memory, retrieval from semantic memory, and a working memory task). The final aim was to determine whether chewing gum improved mood (alertness, calm and hedonic tone). A cross-over design was used with gum and no-gum sessions being on consecutive weeks. In each week, volunteers attended for two sessions, two days apart. The first session assessed mood, immediate recall of information from a story and performance on short memory tasks. The second session assessed mood, delayed recall of information from a story and performance of an intelligence test (the Alice Heim test). There were no significant effects of chewing gum on any aspect of recall of the story. Chewing gum improved the accuracy of performing the Alice Heim test which confirms the benefits of gum on test performance seen in an earlier study. Chewing gum had no significant effect on the short memory tasks. Chewing gum increased alertness at the end of the test session in both parts of the study. This effect was in the region of a 10% increase and was highly significant (P < 0.001). The results of this study showed that chewing gum increases alertness. In contrast, no significant effects of chewing gum were observed in the memory tasks. Intellectual performance was improved in the gum condition. Overall, the results suggest further research on the alerting effects of chewing gum and possible improved test performance in these situations.

Probiotic Bacillus coagulans GBI-30, 6086 reduces exercise-induced muscle damage and increases recovery

PubMed Central

Jäger, Ralf; Shields, Kevin A.; Lowery, Ryan P.; De Souza, Eduardo O.; Partl, Jeremy M.; Hollmer, Chase; Purpura, Martin

2016-01-01

Objective. Probiotics have been reported to support healthy digestive and immune function, aid in protein absorption, and decrease inflammation. Further, a trend to increase vertical jump power has been observed following co-administration of protein and probiotics in resistance-trained subjects. However, to date the potential beneficial effect of probiotics on recovery from high intensity resistance exercise have yet to be explored. Therefore, this study examined the effect of co-administration of protein and probiotics on muscle damage, recovery and performance following a damaging exercise bout. Design. Twenty nine (n = 29) recreationally-trained males (mean ± SD; 21.5 ± 2.8 years; 89.7 ± 28.2 kg; 177.4 ± 8.0 cm) were assigned to consume either 20 g of casein (PRO) or 20 g of casein plus probiotic (1 billion CFU Bacillus coagulans GBI-30, 6086, PROBC) in a crossover, diet-controlled design. After two weeks of supplementation, perceptional measures, athletic performance, and muscle damage were analyzed following a damaging exercise bout. Results. The damaging exercise bout significantly increased muscle soreness, and reduced perceived recovery; however, PROBC significantly increased recovery at 24 and 72 h, and decreased soreness at 72 h post exercise in comparison to PRO. Perceptual measures were confirmed by increases in CK (PRO: +266.8%, p = 0.0002; PROBC: +137.7%, p = 0.01), with PROBC showing a trend towards reduced muscle damage (p = 0.08). The muscle-damaging exercise resulted in significantly increased muscle swelling and Blood Urea Nitrogen levels in both conditions with no difference between groups. The strenuous exercise significantly reduced athletic performance in PRO (Wingate Peak Power; PRO: (−39.8 watts, −5.3%, p = 0.03)), whereas PROBC maintained performance (+10.1 watts, +1.7%). Conclusions. The results provide evidence that probiotic supplementation in combination with protein tended to reduce indices of muscle damage, improves recovery, and maintains physical performance subsequent to damaging exercise. PMID:27547577

The determination of dark adaptation time using electroretinography in conscious Miniature Schnauzer dogs

PubMed Central

Yu, Hyung-Ah; Jeong, Man-Bok; Park, Shin-Ae; Kim, Won-Tae; Kim, Se-Eun; Chae, Je-Min; Yi, Na-Young

2007-01-01

The optimal dark adaptation time of electroretinograms (ERG's) performed on conscious dogs were determined using a commercially available ERG unit with a contact lens electrode and a built-in light source (LED-electrode). The ERG recordings were performed on nine healthy Miniature Schnauzer dogs. The bilateral ERG's at seven different dark adaptation times at an intensity of 2.5 cd·s/m2 was performed. Signal averaging (4 flashes of light stimuli) was adopted to reduce electrophysiologic noise. As the dark adaptation time increased, a significant increase in the mean a-wave amplitudes was observed in comparison to base-line levels up to 10 min (p < 0.05). Thereafter, no significant differences in amplitude occured over the dark adaptation time. Moreover, at this time the mean amplitude was 60.30 ± 18.47 µV. However, no significant changes were observed for the implicit times of the a-wave. The implicit times and amplitude of the b-wave increased significantly up to 20 min of dark adaptation (p < 0.05). Beyond this time, the mean b-wave amplitudes was 132.92 ± 17.79 µV. The results of the present study demonstrate that, the optimal dark adaptation time when performing ERG's, should be at least 20 min in conscious Miniature Schnauzer dogs. PMID:17993756

The determination of dark adaptation time using electroretinography in conscious miniature Schnauzer dogs.

PubMed

Yu, Hyung-Ah; Jeong, Man-Bok; Park, Shin-Ae; Kim, Won-Tae; Kim, Se-Eun; Chae, Je-Min; Yi, Na-Young; Seo, Kang-Moon

2007-12-01

The optimal dark adaptation time of electroretinograms (ERG's) performed on conscious dogs were determined using a commercially available ERG unit with a contact lens electrode and a built-in light source (LED-electrode). The ERG recordings were performed on nine healthy Miniature Schnauzer dogs. The bilateral ERG's at seven different dark adaptation times at an intensity of 2.5 cd.s/m(2) was performed. Signal averaging (4 flashes of light stimuli) was adopted to reduce electrophysiologic noise. As the dark adaptation time increased, a significant increase in the mean a-wave amplitudes was observed in comparison to base-line levels up to 10 min (p < 0.05). Thereafter, no significant differences in amplitude occurred over the dark adaptation time. Moreover, at this time the mean amplitude was 60.30 +/- 18.47 microV. However, no significant changes were observed for the implicit times of the a-wave. The implicit times and amplitude of the b-wave increased significantly up to 20 min of dark adaptation (p < 0.05). Beyond this time, the mean b-wave amplitudes was 132.92 +/- 17.79 microV. The results of the present study demonstrate that, the optimal dark adaptation time when performing ERG's, should be at least 20 min in conscious Miniature Schnauzer dogs.

Increasing within-School Competition: A Case for Department Level Performance Indicators?

ERIC Educational Resources Information Center

Telhaj, Shqiponja; Adnett, Nick; Davies, Peter; Hutton, David; Coe, Robert

2009-01-01

The authors investigate the size and stability of departmental effects in English secondary schooling during a period in which extensions to parental choice and annual publication of school performance tables had significantly increased competitive pressures on schools. Their database of nearly 450 English secondary schools enables them to…

Increase in Jumping Height Associated with Maximal Effort Vertical Depth Jumps.

ERIC Educational Resources Information Center

Bedi, John F.; And Others

1987-01-01

In order to assess if there existed a statistically significant increase in jumping performance when dropping from different heights, 32 males, aged 19 to 26, performed a series of maximal effort vertical jumps after dropping from eight heights onto a force plate. Results are analyzed. (Author/MT)

Obesity-induced oxidative stress, accelerated functional decline with age and increased mortality in mice.

PubMed

Zhang, Yiqiang; Fischer, Kathleen E; Soto, Vanessa; Liu, Yuhong; Sosnowska, Danuta; Richardson, Arlan; Salmon, Adam B

2015-06-15

Obesity is a serious chronic disease that increases the risk of numerous co-morbidities including metabolic syndrome, cardiovascular disease and cancer as well as increases risk of mortality, leading some to suggest this condition represents accelerated aging. Obesity is associated with significant increases in oxidative stress in vivo and, despite the well-explored relationship between oxidative stress and aging, the role this plays in the increased mortality of obese subjects remains an unanswered question. Here, we addressed this by undertaking a comprehensive, longitudinal study of a group of high fat-fed obese mice and assessed both their changes in oxidative stress and in their performance in physiological assays known to decline with aging. In female C57BL/6J mice fed a high-fat diet starting in adulthood, mortality was significantly increased as was oxidative damage in vivo. High fat-feeding significantly accelerated the decline in performance in several assays, including activity, gait, and rotarod. However, we also found that obesity had little effect on other markers of function and actually improved performance in grip strength, a marker of muscular function. Together, this first comprehensive assessment of longitudinal, functional changes in high fat-fed mice suggests that obesity may induce segmental acceleration of some of the aging process. Published by Elsevier Inc.

Obesity-induced oxidative stress, accelerated functional decline with age and increased mortality in mice

PubMed Central

Zhang, Yiqiang; Fischer, Kathleen E.; Soto, Vanessa; Liu, Yuhong; Sosnowska, Danuta; Richardson, Arlan; Salmon, Adam B.

2015-01-01

Obesity is a serious chronic disease that increases the risk of numerous co-morbidities including metabolic syndrome, cardiovascular disease and cancer as well as increases risk of mortality leading some to suggest this represents accelerated aging. Obesity is associated with significant increases in oxidative stress in vivo and, despite the well-explored relationship between oxidative stress and aging, the role this plays in the increased mortality of obese subjects remains an unanswered question. Here, we addressed this by undertaking a comprehensive, longitudinal study of a group of high fat-fed obese mice and assessed both their changes in oxidative stress and in their performance in physiological assays known to decline with aging. In female C57BL/6J mice fed a high-fat diet starting in adulthood, mortality was significantly increased in high fat-fed mice as was oxidative damage in vivo. High fat-feeding significantly accelerated the decline in performance in several assays, including activity, gait, and rotarod. However, we also found that obesity had little effect on other markers and actually improved performance in grip strength, a marker of muscular function. Together, this first comprehensive assessment of longitudinal functional changes in high fat-fed mice suggests that obesity may induce segmental acceleration of some of the aging process. PMID:25558793

Substantial Progress Yet Significant Opportunity for Improvement in Stroke Care in China.

PubMed

Li, Zixiao; Wang, Chunjuan; Zhao, Xingquan; Liu, Liping; Wang, Chunxue; Li, Hao; Shen, Haipeng; Liang, Li; Bettger, Janet; Yang, Qing; Wang, David; Wang, Anxin; Pan, Yuesong; Jiang, Yong; Yang, Xiaomeng; Zhang, Changqing; Fonarow, Gregg C; Schwamm, Lee H; Hu, Bo; Peterson, Eric D; Xian, Ying; Wang, Yilong; Wang, Yongjun

2016-11-01

Stroke is a leading cause of death in China. Yet the adherence to guideline-recommended ischemic stroke performance metrics in the past decade has been previously shown to be suboptimal. Since then, several nationwide stroke quality management initiatives have been conducted in China. We sought to determine whether adherence had improved since then. Data were obtained from the 2 phases of China National Stroke Registries, which included 131 hospitals (12 173 patients with acute ischemic stroke) in China National Stroke Registries phase 1 from 2007 to 2008 versus 219 hospitals (19 604 patients) in China National Stroke Registries phase 2 from 2012 to 2013. Multiple regression models were developed to evaluate the difference in adherence to performance measure between the 2 study periods. The overall quality of care has improved over time, as reflected by the higher composite score of 0.76 in 2012 to 2013 versus 0.63 in 2007 to 2008. Nine of 13 individual performance metrics improved. However, there were no significant improvements in the rates of intravenous thrombolytic therapy and anticoagulation for atrial fibrillation. After multivariate analysis, there remained a significant 1.17-fold (95% confidence interval, 1.14-1.21) increase in the odds of delivering evidence-based performance metrics in the more recent time periods versus older data. The performance metrics with the most significantly increased odds included stroke education, dysphagia screening, smoking cessation, and antithrombotics at discharge. Adherence to stroke performance metrics has increased over time, but significant opportunities remain for further improvement. Continuous stroke quality improvement program should be developed as a national priority in China. © 2016 American Heart Association, Inc.

Effects of Xylo-Oligosaccharides on Broiler Chicken Performance and Microbiota

PubMed Central

De Maesschalck, C.; Eeckhaut, V.; Maertens, L.; De Lange, L.; Marchal, L.; Nezer, C.; De Baere, S.; Croubels, S.; Daube, G.; Dewulf, J.; Haesebrouck, F.; Ducatelle, R.; Taminau, B.

2015-01-01

In broiler chickens, feed additives, including prebiotics, are widely used to improve gut health and to stimulate performance. Xylo-oligosaccharides (XOS) are hydrolytic degradation products of arabinoxylans that can be fermented by the gut microbiota. In the current study, we aimed to analyze the prebiotic properties of XOS when added to the broiler diet. Administration of XOS to chickens, in addition to a wheat-rye-based diet, significantly improved the feed conversion ratio. XOS significantly increased villus length in the ileum. It also significantly increased numbers of lactobacilli in the colon and Clostridium cluster XIVa in the ceca. Moreover, the number of gene copies encoding the key bacterial enzyme for butyrate production, butyryl-coenzyme A (butyryl-CoA):acetate CoA transferase, was significantly increased in the ceca of chickens administered XOS. In this group of chickens, at the species level, Lactobacillus crispatus and Anaerostipes butyraticus were significantly increased in abundance in the colon and cecum, respectively. In vitro fermentation of XOS revealed cross-feeding between L. crispatus and A. butyraticus. Lactate, produced by L. crispatus during XOS fermentation, was utilized by the butyrate-producing Anaerostipes species. These data show the beneficial effects of XOS on broiler performance when added to the feed, which potentially can be explained by stimulation of butyrate-producing bacteria through cross-feeding of lactate and subsequent effects of butyrate on gastrointestinal function. PMID:26092452

The effects of clinical pilates exercises on bone mineral density, physical performance and quality of life of women with postmenopausal osteoporosis.

PubMed

Angın, Ender; Erden, Zafer; Can, Filiz

2015-01-01

The aim of this study was to investigate effects of Clinical Pilates Exercises on bone mineral density (BMD), physical performance and quality of life (QOL) in postmenopausal osteoporosis. Forty-one women were recruited to the study. The subjects were divided into two groups, as the Pilates group and the control group. Subjects were evaluated for BMD at the lumbar region. Physical performance level was measured. Pain intensity level was scored with Visual Analogue Scale. QUALEFFO-41 was used for assessing QOL. BMD values increased in the Pilates group (p < 0.05), while BMD decreased in the control group (p< 0.05). Physical performance test results showed significant increases in the Pilates group (p< 0.05) whereas there was no changes in the control group (p> 0.05). Pain intensity level in the Pilates group was significantly decreased after the exercise (p< 0.05), while it was unchanged in the control group. There were significant increases in all parameters of QOL in the Pilates group. Conversely, some parameters of QOL showed decreases in the control group (p< 0.05). Pilates Exercises is effective to increase BMD; QOL and walking distance and also beneficial to relieve pain. Physiotherapist can use Pilates Exercises for the subjects with osteoporosis in the clinics.

Decision-making Strategies and Performance among Seniors1

PubMed Central

Besedeš, Tibor; Deck, Cary; Sarangi, Sudipta; Shor, Mikhael

2011-01-01

Using paper and pencil experiments administered in senior centers, we examine decision-making performance in multi-attribute decision problems. We differentiate the effects of declining cognitive performance and changing cognitive process on decision-making performance of seniors as they age. We find a significant decline in performance with age due to reduced reliance on common heuristics and increased decision-making randomness among our oldest subjects. However, we find that increasing the number of options in a decision problem increases the number of heuristics brought to the task. This challenges the choice overload view that people give up when confronted with too much choice. PMID:22408282

Multimodal airway evaluation in growing patients after rapid maxillary expansion.

PubMed

Fastuca, R; Meneghel, M; Zecca, P A; Mangano, F; Antonello, M; Nucera, R; Caprioglio, A

2015-06-01

The objective of this study was to evaluate the airway volume of growing patients combining a morphological approach using cone beam computed tomography associated with functional data obtained by polysomnography examination after rapid maxillary expansion treatment. 22 Caucasian patients (mean age 8.3±0.9 years) undergoing rapid maxillary expansion with Haas type expander banded on second deciduous upper molars were enrolled for this prospective study. Cone beam computed tomography scans and polysomnography exams were collected before placing the appliance (T0) and after 12 months (T1). Image processing with airway volume computing and analyses of oxygen saturation and apnoea/hypopnoea index were performed. Airway volume, oxygen saturation and apnea/hypopnea index underwent significant increase over time. However, no significant correlation was seen between their increases. The rapid maxillary expansion treatment induced significant increases in the total airway volume and respiratory performance. Functional respiratory parameters should be included in studies evaluating the RME treatment effects on the respiratory performance.

Responses of tree and insect herbivores to elevated nitrogen inputs: A meta-analysis

NASA Astrophysics Data System (ADS)

Li, Furong; Dudley, Tom L.; Chen, Baoming; Chang, Xiaoyu; Liang, Liyin; Peng, Shaolin

2016-11-01

Increasing atmospheric nitrogen (N) inputs have the potential to alter terrestrial ecosystem function through impacts on plant-herbivore interactions. The goal of our study is to search for a general pattern in responses of tree characteristics important for herbivores and insect herbivorous performance to elevated N inputs. We conducted a meta-analysis based on 109 papers describing impacts of nitrogen inputs on tree characteristics and 16 papers on insect performance. The differences in plant characteristics and insect performance between broadleaves and conifers were also explored. Tree aboveground biomass, leaf biomass and leaf N concentration significantly increased under elevated N inputs. Elevated N inputs had no significantly overall effect on concentrations of phenolic compounds and lignin but adversely affected tannin, as defensive chemicals for insect herbivores. Additionally, the overall effect of insect herbivore performance (including development time, insect biomass, relative growth rate, and so on) was significantly increased by elevated N inputs. According to the inconsistent responses between broadleaves and conifers, broadleaves would be more likely to increase growth by light interception and photosynthesis rather than producing more defensive chemicals to elevated N inputs by comparison with conifers. Moreover, the overall carbohydrate concentration was significantly reduced by 13.12% in broadleaves while increased slightly in conifers. The overall tannin concentration decreased significantly by 39.21% in broadleaves but a 5.8% decrease in conifers was not significant. The results of the analysis indicated that elevated N inputs would provide more food sources and ameliorate tree palatability for insects, while the resistance of trees against their insect herbivores was weakened, especially for broadleaves. Thus, global forest insect pest problems would be aggravated by elevated N inputs. As N inputs continue to rise in the future, forest ecosystem management should pay more attention to insect pest, especially in the regions dominated by broadleaves.

Thrust Augmented Nozzle for a Hybrid Rocket with a Helical Fuel Port

NASA Astrophysics Data System (ADS)

Marshall, Joel H.

A thrust augmented nozzle for hybrid rocket systems is investigated. The design lever-ages 3-D additive manufacturing to embed a helical fuel port into the thrust chamber of a hybrid rocket burning gaseous oxygen and ABS plastic as propellants. The helical port significantly increases how quickly the fuel burns, resulting in a fuel-rich exhaust exiting the nozzle. When a secondary gaseous oxygen flow is injected into the nozzle downstream of the throat, all of the remaining unburned fuel in the plume spontaneously ignites. This secondary reaction produces additional high pressure gases that are captured by the nozzle and significantly increases the motor's performance. Secondary injection and combustion allows a high expansion ratio (area of the nozzle exit divided by area of the throat) to be effective at low altitudes where there would normally be significantly flow separation and possibly an embedded shock wave due. The result is a 15 percent increase in produced thrust level with no loss in engine efficiency due to secondary injection. Core flow efficiency was increased significantly. Control tests performed using cylindrical fuel ports with secondary injection, and helical fuel ports without secondary injection did not exhibit this performance increase. Clearly, both the fuel-rich plume and secondary injection are essential features allowing the hybrid thrust augmentation to occur. Techniques for better design optimization are discussed.

Effect of Gas Pressure on Polarization of SOFC Cathode Prepared by Plasma Spray

NASA Astrophysics Data System (ADS)

Li, Cheng-Xin; Wang, Zhun-Zhun; Liu, Shuai; Li, Chang-Jiu

2013-06-01

A cermet-supported tubular SOFC was fabricated using thermal spray. The cell performance was investigated at temperatures from 750 to 900 °C and pressures from 0.1 to 0.5 MPa to examine the effect of operating gas pressure on the cell performance. The influence of gas pressure on the cathodic polarization was studied through the electrochemical impedance approach to examine the controlling electrochemical processes during cell operation. Results show that increasing the operating gas pressure improves the power output performance significantly. When the gas pressure is increased from 0.1 to 0.3 MPa, the maximum power density is increased by a factor of 32% at a temperature of 800 °C. The cathode polarization decreases significantly with the increase of the gas pressure. The electrochemical analysis shows that the main control processes of the cathode reaction are the oxygen species transfer at the three-phase boundary and oxygen diffusion on the surface or in the bulk of the cathode, which are enhanced with increasing gas pressure.

The effects of substitute multisensory feedback on task performance and the sense of presence in a virtual reality environment

PubMed Central

Milella, Ferdinando; Pinto, Carlo; Cant, Iain; White, Mark; Meyer, Georg

2018-01-01

Objective and subjective measures of performance in virtual reality environments increase as more sensory cues are delivered and as simulation fidelity increases. Some cues (colour or sound) are easier to present than others (object weight, vestibular cues) so that substitute cues can be used to enhance informational content in a simulation at the expense of simulation fidelity. This study evaluates how substituting cues in one modality by alternative cues in another modality affects subjective and objective performance measures in a highly immersive virtual reality environment. Participants performed a wheel change in a virtual reality (VR) environment. Auditory, haptic and visual cues, signalling critical events in the simulation, were manipulated in a factorial design. Subjective ratings were recorded via questionnaires. The time taken to complete the task was used as an objective performance measure. The results show that participants performed best and felt an increased sense of immersion and involvement, collectively referred to as ‘presence’, when substitute multimodal sensory feedback was provided. Significant main effects of audio and tactile cues on task performance and on participants' subjective ratings were found. A significant negative relationship was found between the objective (overall completion times) and subjective (ratings of presence) performance measures. We conclude that increasing informational content, even if it disrupts fidelity, enhances performance and user’s overall experience. On this basis we advocate the use of substitute cues in VR environments as an efficient method to enhance performance and user experience. PMID:29390023

The effects of substitute multisensory feedback on task performance and the sense of presence in a virtual reality environment.

PubMed

Cooper, Natalia; Milella, Ferdinando; Pinto, Carlo; Cant, Iain; White, Mark; Meyer, Georg

2018-01-01

Objective and subjective measures of performance in virtual reality environments increase as more sensory cues are delivered and as simulation fidelity increases. Some cues (colour or sound) are easier to present than others (object weight, vestibular cues) so that substitute cues can be used to enhance informational content in a simulation at the expense of simulation fidelity. This study evaluates how substituting cues in one modality by alternative cues in another modality affects subjective and objective performance measures in a highly immersive virtual reality environment. Participants performed a wheel change in a virtual reality (VR) environment. Auditory, haptic and visual cues, signalling critical events in the simulation, were manipulated in a factorial design. Subjective ratings were recorded via questionnaires. The time taken to complete the task was used as an objective performance measure. The results show that participants performed best and felt an increased sense of immersion and involvement, collectively referred to as 'presence', when substitute multimodal sensory feedback was provided. Significant main effects of audio and tactile cues on task performance and on participants' subjective ratings were found. A significant negative relationship was found between the objective (overall completion times) and subjective (ratings of presence) performance measures. We conclude that increasing informational content, even if it disrupts fidelity, enhances performance and user's overall experience. On this basis we advocate the use of substitute cues in VR environments as an efficient method to enhance performance and user experience.

Effects of posture on exercise performance - Measurement by systolic time intervals.

NASA Technical Reports Server (NTRS)

Spodick, D. H.; Quarry-Pigott, V. M.

1973-01-01

Because posture significantly influences cardiac performance, the effects of moderate supine and upright ergometer exercise were compared on the basis of proportional (+37%) rate increments over resting control. Supine exercise produced significant decreases in left ventricular ejection time (LVET), pre-ejection period (PEP), and isovolumic contraction time (IVCT). Ejection time index (ETI) and corrected ejection time (LVETc) did not change significantly. Upright exercise produced greater decreases in PEP and LVET, but despite the rate increase there was no change in LVET, which resulted in sharp increases in ETI and LVETc. The discordant directional effects on LVET and its rate-correcting indices between the two postures were consistent with hemodynamic studies demonstrating lack of stroke volume change during supine exercise and increased stroke volume over control during light to moderate upright exercise.

Light at Night and Measures of Alertness and Performance: Implications for Shift Workers.

PubMed

Figueiro, Mariana G; Sahin, Levent; Wood, Brittany; Plitnick, Barbara

2016-01-01

Rotating-shift workers, particularly those working at night, are likely to experience sleepiness, decreased productivity, and impaired safety while on the job. Light at night has been shown to have acute alerting effects, reduce sleepiness, and improve performance. However, light at night can also suppress melatonin and induce circadian disruption, both of which have been linked to increased health risks. Previous studies have shown that long-wavelength (red) light exposure increases objective and subjective measures of alertness at night, without suppressing nocturnal melatonin. This study investigated whether exposure to red light at night would not only increase measures of alertness but also improve performance. It was hypothesized that exposure to both red (630 nm) and white (2,568 K) lights would improve performance but that only white light would significantly affect melatonin levels. Seventeen individuals participated in a 3-week, within-subjects, nighttime laboratory study. Compared to remaining in dim light, participants had significantly faster reaction times in the GO/NOGO test after exposure to both red light and white light. Compared to dim light exposure, power in the alpha and alpha-theta regions was significantly decreased after exposure to red light. Melatonin levels were significantly suppressed by white light only. Results show that not only can red light improve measures of alertness, but it can also improve certain types of performance at night without affecting melatonin levels. These findings could have significant practical applications for nurses; red light could help nurses working rotating shifts maintain nighttime alertness, without suppressing melatonin or changing their circadian phase. © The Author(s) 2015.

High altitude cognitive performance and COPD interaction

PubMed Central

Kourtidou-Papadeli, C; Papadelis, C; Koutsonikolas, D; Boutzioukas, S; Styliadis, C; Guiba-Tziampiri, O

2008-01-01

Introduction: Thousands of people work and perform everyday in high altitude environment, either as pilots, or shift workers, or mountaineers. The problem is that most of the accidents in this environment have been attributed to human error. The objective of this study was to assess complex cognitive performance as it interacts with respiratory insufficiency at altitudes of 8000 feet and identify the potential effect of hypoxia on safe performance. Methods: Twenty subjects participated in the study, divided in two groups: Group I with mild asymptomatic chronic obstructive pulmonary disease (COPD), and Group II with normal respiratory function. Altitude was simulated at 8000 ft. using gas mixtures. Results: Individuals with mild COPD experienced notable hypoxemia with significant performance decrements and increased number of errors at cabin altitude, compared to normal subjects, whereas their blood pressure significantly increased. PMID:19048098

Does Focus of Attention Improve Snatch Lift Kinematics?

PubMed

Schutts, Kyle S; Wu, Will F W; Vidal, Anthony D; Hiegel, Jamie; Becker, James

2017-10-01

Recent motor control literature has demonstrated that using verbal instructions to direct a performer's attention externally (i.e., toward the movement outcome) enhances motor skill performance. The purpose of this study was to investigate how an athlete's focus of attention impacts kinematic performance of the snatch. Using a counterbalanced within-participant design, 12 competitively trained athletes (8 male and 4 female athletes) performed 2 instructional blocks of 3 snatch repetitions at 80% of their most recent training 1 repetition maximum. Blocks of internal and external instructions were given to the athlete in a random fashion. Results showed that, when focusing internally, athletes significantly (p ≤ 0.05) increased elbow velocity relative to focusing externally, whereas the external instructions significantly increased horizontal barbell velocity, relative to internal instructions. Additionally, an internal focus resulted in significantly larger barbell-cervical-hip angles at maximum height of the barbell compared with an external focus, indicating that the athletes squatted under the barbell too soon. This information adds to the literature suggesting small changes in coaching instructions can impact performance significantly. It is recommended that coaches use instructions that direct an athlete's attention externally, toward the movement outcome, rather than the action itself.

Macular Carotenoid Supplementation Improves Visual Performance, Sleep Quality, and Adverse Physical Symptoms in Those with High Screen Time Exposure

PubMed Central

Stringham, James M.; Stringham, Nicole T.; O’Brien, Kevin J.

2017-01-01

The dramatic rise in the use of smartphones, tablets, and laptop computers over the past decade has raised concerns about potentially deleterious health effects of increased “screen time” (ST) and associated short-wavelength (blue) light exposure. We determined baseline associations and effects of 6 months’ supplementation with the macular carotenoids (MC) lutein, zeaxanthin, and mesozeaxanthin on the blue-absorbing macular pigment (MP) and measures of sleep quality, visual performance, and physical indicators of excessive ST. Forty-eight healthy young adults with at least 6 h of daily near-field ST exposure participated in this placebo-controlled trial. Visual performance measures included contrast sensitivity, critical flicker fusion, disability glare, and photostress recovery. Physical indicators of excessive screen time and sleep quality were assessed via questionnaire. MP optical density (MPOD) was assessed via heterochromatic flicker photometry. At baseline, MPOD was correlated significantly with all visual performance measures (p < 0.05 for all). MC supplementation (24 mg daily) yielded significant improvement in MPOD, overall sleep quality, headache frequency, eye strain, eye fatigue, and all visual performance measures, versus placebo (p < 0.05 for all). Increased MPOD significantly improves visual performance and, in turn, improves several undesirable physical outcomes associated with excessive ST. The improvement in sleep quality was not directly related to increases in MPOD, and may be due to systemic reduction in oxidative stress and inflammation. PMID:28661438

Macular Carotenoid Supplementation Improves Visual Performance, Sleep Quality, and Adverse Physical Symptoms in Those with High Screen Time Exposure.

PubMed

Stringham, James M; Stringham, Nicole T; O'Brien, Kevin J

2017-06-29

The dramatic rise in the use of smartphones, tablets, and laptop computers over the past decade has raised concerns about potentially deleterious health effects of increased "screen time" (ST) and associated short-wavelength (blue) light exposure. We determined baseline associations and effects of 6 months' supplementation with the macular carotenoids (MC) lutein, zeaxanthin, and mesozeaxanthin on the blue-absorbing macular pigment (MP) and measures of sleep quality, visual performance, and physical indicators of excessive ST. Forty-eight healthy young adults with at least 6 h of daily near-field ST exposure participated in this placebo-controlled trial. Visual performance measures included contrast sensitivity, critical flicker fusion, disability glare, and photostress recovery. Physical indicators of excessive screen time and sleep quality were assessed via questionnaire. MP optical density (MPOD) was assessed via heterochromatic flicker photometry. At baseline, MPOD was correlated significantly with all visual performance measures ( p < 0.05 for all). MC supplementation (24 mg daily) yielded significant improvement in MPOD, overall sleep quality, headache frequency, eye strain, eye fatigue, and all visual performance measures, versus placebo ( p < 0.05 for all). Increased MPOD significantly improves visual performance and, in turn, improves several undesirable physical outcomes associated with excessive ST. The improvement in sleep quality was not directly related to increases in MPOD, and may be due to systemic reduction in oxidative stress and inflammation.

Main and Interaction Effects of Metallic Pollutants on Cognitive Functioning.

ERIC Educational Resources Information Center

Moon, Charles; And Others

1985-01-01

A study involving 69 randomly selected elementary students indicated that increases in arsenic and interaction of arsenic lead were significantly related to decreased reading and spelling achievement, and increases in aluminum and the interaction of aluminum with lead were significantly related to decreased visual-motor performance. (Author/CL)

Improving neuromuscular performance in young basketball players: plyometric vs. technique training.

PubMed

Attene, G; Iuliano, E; Di Cagno, A; Calcagno, G; Moalla, W; Aquino, G; Padulo, J

2015-01-01

The aim of this study was to compare the effects of plyometric training versus basketball technique training on improving neuro-muscular performance. Thirty-six (age 14.9±0.9 years, body height 164.0±7.6 cm, body weight 54.0±8.7 kg, BMI 20.1±2.4 kg·m-2) basketball players girls were randomly allocated to 2 groups: Basketball Plyometric Training (BPT, N.=18) and Basketball Technique Training (BTT, N.=18). The players were tested by two specific tests: counter movement jump (CMJ) and squat jump (SJ) before and after 6 training weeks. The jump height, as dependent variable, showed a different trend as an effect of the different training protocols, in contrast with the current knowledge. Manova did not show significant interactions between the two groups for the height of jumps, while significant differences were found for interaction time × training (P<0.05) and for main effect × time (P<0.001). After training, the BPT group increased significantly CMJ performance by 11.3% (P<0.05), whereas the BTT group increased by 4.6%. Likewise, the BPT group demonstrated a significant greater improvement of jump height than BTT group (an increase of 15.4% vs. 7.5%, P<0.01; respectively). These results suggest that both training protocols proposed in this study improved vertical jump performance. However, a combination of the two protocols, plyometric training and sport-specific-exercises, could be useful to optimize performance by an easy transition from controlled a-specific to sport-specific performance requirements. In conclusion, BPT is a safe and effective method of achieving a favourable neuro-muscular performance than BTT in female basketball players.

Use of the Combined First-Trimester Screen in High- and Low-Risk Patient Populations After Introduction of Noninvasive Prenatal Testing.

PubMed

Larion, Sebastian; Warsof, Steven L; Romary, Letty; Mlynarczyk, Margaret; Peleg, David; Abuhamad, Alfred Z

2015-08-01

To report changes in the use of the combined first-trimester screen (FTS) in patients classified as high and low risk for fetal aneuploidy, including after introduction of noninvasive prenatal testing (NIPT). A prospectively collected database was reviewed to investigate changes in FTS use before and after American College of Obstetricians and Gynecologists (ACOG) Practice Bulletin No. 77 (Obstet Gynecol 2007; 109:217-227), which recommended that all patients be offered aneuploidy screening, and after NIPT introduction. High-risk patients were classified as 35 years or older at the estimated time of delivery or those with an abnormal prior screen, abnormal ultrasound findings, or family history of aneuploidy. Data were normalized per 100 morphologic ultrasound examinations to account for changes in patient number over time. Statistical significance was defined as P < .05. A total of 10,125 FTSs were recorded during the 88-month study period, including 2962 in high-risk patients and 7163 in low-risk patients. The total number of FTSs performed per 100 morphologic ultrasound examinations significantly increased after ACOG Practice Bulletin No. 77 and significantly decreased after NIPT introduction. In high-risk patients, the total number of FTSs performed per 100 morphologic ultrasound examinations significantly increased after ACOG Practice Bulletin No. 77 but significantly decreased after NIPT introduction. In contrast, in low-risk patients, the total number of FTSs performed per 100 morphologic ultrasound examinations significantly increased after ACOG Practice Bulletin No.77 but was not statistically different after NIPT introduction. American College of Obstetricians and Gynecologists Practice Bulletin No. 77 significantly increased patient use of FTS. The introduction of NIPT significantly decreased FTS use in the high-risk population but not in the low-risk population. © 2015 by the American Institute of Ultrasound in Medicine.

Changes in combat task performance under increasing loads in active duty marines.

PubMed

Jaworski, Rebecca L; Jensen, Andrew; Niederberger, Brenda; Congalton, Robert; Kelly, Karen R

2015-03-01

U.S. Marines perform mission tasks under heavy loads which may compromise performance of combat tasks. However, data supporting this performance decrement are limited. The aim of this study was to determine the effects of load on performance of combat-related tasks. Subjects (N=18) ran a modified Maneuver Under Fire ([MANUF], 300 yards [yd] total: two 25-yd sprints, 25-yd crawl, 75-yd casualty drag, 150-yd ammunition can carry, and grenade toss) portion of the U.S. Marine Corps Combat Fitness Test under 4 trial conditions: neat (no load), 15%, 30%, and 45% of body weight, with a shooting task pre- and post-trial. There was a significant increase in total time to completion as a function of load (p<0.0001) with a relationship between load and time (r=0.592, p<0.0001). Pre- to post-MANUF shot accuracy (p=0.005) and precision (p<0.0001) was reduced. Short aerobic performance is significantly impacted by increasing loads. Marksmanship is compromised as a function of fatigue and load. These data suggest that loads of 45% body weight increase time to cover distance and reduce the ability to precisely hit a target. Reprint & Copyright © 2015 Association of Military Surgeons of the U.S.

Effects on Task Performance and Psychophysiological Measures of Performance During Normobaric Hypoxia Exposure

NASA Technical Reports Server (NTRS)

Stephens, Chad; Kennedy, Kellie; Napoli, Nicholas; Demas, Matthew; Barnes, Laura; Crook, Brenda; Williams, Ralph; Last, Mary Carolyn; Schutte, Paul

2017-01-01

Human-autonomous systems have the potential to mitigate pilot cognitive impairment and improve aviation safety. A research team at NASA Langley conducted an experiment to study the impact of mild normobaric hypoxia induction on aircraft pilot performance and psychophysiological state. A within-subjects design involved non-hypoxic and hypoxic exposures while performing three 10-minute tasks. Results indicated the effect of 15,000 feet simulated altitude did not induce significant performance decrement but did produce increase in perceived workload. Analyses of psychophysiological responses evince the potential of biomarkers for hypoxia onset. This study represents on-going work at NASA intending to add to the current knowledge of psychophysiologically-based input to automation to increase aviation safety. Analyses involving coupling across physiological systems and wavelet transforms of cortical activity revealed patterns that can discern between the simulated altitude conditions. Specifically, multivariate entropy of ECG/Respiration components were found to be significant predictors (p< 0.02) of hypoxia. Furthermore, in EEG, there was a significant decrease in mid-level beta (15.19-18.37Hz) during the hypoxic condition in thirteen of sixteen sites across the scalp. Task performance was not appreciably impacted by the effect of 15,000 feet simulated altitude. Analyses of psychophysiological responses evince the potential of biomarkers for mild hypoxia onset.The potential for identifying shifts in underlying cortical and physiological systems could serve as a means to identify the onset of deteriorated cognitive state. Enabling such assessment in future flightdecks could permit increasingly autonomous systems-supported operations. Augmenting human operator through assessment of cognitive impairment has the potential to further improve operator performance and mitigate human error in safety critical contexts. This study represents ongoing work at NASA intending to add to the current knowledge of psychophysiologically-based input to automation to increase aviation safety.

Effects of boldenone undecylenate on growth performance, maintenance behaviour, reproductive hormones and carcass traits of growing rabbits.

PubMed

Mohammed, H H; Badawi, M E; El-Tarabany, M S; Rania, M

2016-01-01

The present study was done to evaluate the effect of boldenone undecylenate (BOL) on growth performance, maintenance behaviour, reproductive hormones and carcass traits of male rabbits. Sixty apparently healthy New Zealand White male rabbits, 5 weeks of age, were allotted to 3 equal groups. Each group was subdivided into 5 replicates, where the first group is control. The second group (B1) comprised rabbits that received 2 intramuscular injections of BOL (5 mg/kg) with 3 week intervals (9 and 12 weeks of age), while the third group (B2) included rabbits that received 3 intramuscular injections of BOL (5 mg/kg) with 2 week intervals (8, 10 and 12 weeks of age). The end of the trial was after 4 weeks from the last injection (16 weeks of age). The results revealed that the treated groups had a significant increase in total body weight, daily gain and feed efficiency, with a significant decrease in feed conversion ratio (FCR). Ingestive, locomotion and grooming behaviors were significantly higher in treated groups. Lateral pasture and exploratory behaviors were significantly higher in the control group. Administration of BOL resulted in a significant increase in dressing % and a significant decrease in testes %. Groups treated with BOL had a significantly (P<0.05) decreased serum testosterone level, simultaneously with a significantly increased estradiol level. The results indicate that BOL improves performance and carcass traits. Furthermore, there are hormonal-behavioral correlations through enhancement of ingestive and locomotion behaviors of treated animals.

Intermittent Punishment of Self-stimulation: Effectiveness During Application and Extinction

ERIC Educational Resources Information Center

Romanczyk, Raymond G.

1977-01-01

Two studies were performed comparing the effectiveness of fixed-ratio (FR) and variable-ratio (VR) schedules of punishment during application and extinction. Subjects were two young children. Both studies found significant positive "side effects" of punishment in terms of increased play and social behavior as well as increased performance of…

Tomosynthesis for the early detection of pulmonary emphysema: diagnostic performance compared with chest radiography, using multidetector computed tomography as reference.

PubMed

Yamada, Yoshitake; Jinzaki, Masahiro; Hashimoto, Masahiro; Shiomi, Eisuke; Abe, Takayuki; Kuribayashi, Sachio; Ogawa, Kenji

2013-08-01

To compare the diagnostic performance of tomosynthesis with that of chest radiography for the detection of pulmonary emphysema, using multidetector computed tomography (MDCT) as reference. Forty-eight patients with and 63 without pulmonary emphysema underwent chest MDCT, tomosynthesis and radiography on the same day. Two blinded radiologists independently evaluated the tomosynthesis images and radiographs for the presence of pulmonary emphysema. Axial and coronal MDCT images served as the reference standard and the percentage lung volume with attenuation values of -950 HU or lower (LAA-950) was evaluated to determine the extent of emphysema. Receiver-operating characteristic (ROC) analysis and generalised estimating equations model were used. ROC analysis revealed significantly better performance (P < 0.0001) of tomosynthesis than radiography for the detection of pulmonary emphysema. The average sensitivity, specificity, positive predictive value and negative predictive value of tomosynthesis were 0.875, 0.968, 0.955 and 0.910, respectively, whereas the values for radiography were 0.479, 0.913, 0.815 and 0.697, respectively. For both tomosynthesis and radiography, the sensitivity increased with increasing LAA-950. The diagnostic performance of tomosynthesis was significantly superior to that of radiography for the detection of pulmonary emphysema. In both tomosynthesis and radiography, the sensitivity was affected by the LAA-950. • Tomosynthesis showed significantly better diagnostic performance for pulmonary emphysema than radiography. • Interobserver agreement for tomosynthesis was significantly higher than that for radiography. • Sensitivity increased with increasing LAA -950 in both tomosynthesis and radiography. • Tomosynthesis imparts a similar radiation dose to two projection chest radiography. • Radiation dose and cost of tomosynthesis are lower than those of MDCT.

Effects of dust accumulation and module cleaning on performance ratio of solar rooftop system and solar power plants

NASA Astrophysics Data System (ADS)

Sakarapunthip, Nattakarn; Chenvidhya, Dhirayut; Chuangchote, Surawut; Kirtikara, Krissanapong; Chenvidhya, Tanokkorn; Onreabroy, Wandee

2017-08-01

Thailand is an agricultural country, with rice, sugar, and cassava as the major export products. Production of rice, sugar cane, and cassava entails agricultural activities that give rise to significant airborne dusts. In this work, five photovoltaic (PV) units (one solar rooftop and four power plants) are selected for the study. From the study of dust accumulation on glass surface located near rice farms, it was found that opaque areas due to the deposition of dust are 11-14% after 1-2-week exposure. As a consequence, PV system performance is affected. Performance ratio was calculated to determine these effects. Overall results reveal that during the dry and hot seasons, dust deposition significantly affects the performance ratio. The performance ratio reduces by 1.6-3% for 1-month dust accumulation and reduces by 6-8% for 2-month dust accumulation. After cleaning the dust accumulated, the performance ratio greatly increases, resulting in the increase in the energy output by 10%. This increase provides economic and cost benefits of PV cleaning. The performance ratio is not significantly changed during the rainy season, which PV modules are relatively clean as the dust is washed away by rain. It was also found that most of the solar power plants in Thailand still rely on manual cleaning of PV modules with washing water followed by wiping. However, only one power plant, employs a machine for cleaning, resulting in lower cleaning costs.

Training-induced increase in nitric oxide metabolites in chronic heart failure and coronary artery disease: an extra benefit of water-based exercises?

PubMed

Laurent, Mourot; Daline, Teffaha; Malika, Bouhaddi; Fawzi, Ounissi; Philippe, Vernochet; Benoit, Dugue; Catherine, Monpère; Jacques, Regnard

2009-04-01

Rehabilitation programs involving immersed exercises are more and more frequently used, with severe cardiac patients as well. This study investigated whether a rehabilitation program including water-based exercises has additional effects on the cardiovascular system compared with a traditional land-based training in heart disease patients. Twenty-four male stable chronic heart failure patients and 24 male coronary artery disease patients with preserved left ventricular function participated in the study. Patients took part in the rehabilitation program performing cycle endurance exercises on land. They also performed gymnastic exercises either on land (first half of the participants) or in water (second half). Resting plasma concentration of nitric oxide metabolites (nitrate and nitrite) and catecholamine were evaluated, and a symptom-limited exercise test on a cycle ergometer was performed before and after the rehabilitation program. In the groups performing water-based exercises, the plasma concentration of nitrates was significantly increased (P = 0.035 for chronic heart failure and P = 0.042 for coronary artery disease), whereas it did not significantly change in the groups performing gymnastic exercise on land. No changes in plasma catecholamine concentration occurred. In every group, the cardiorespiratory capacity of patients was significantly increased after rehabilitation. The water-based exercises seemed to effectively increase the basal level of plasma nitrates. Such changes may be related to an enhancement of endothelial function and may be of importance for the health of the patients.

The rewarding value of good motor performance in the context of monetary incentives.

PubMed

Lutz, Kai; Pedroni, Andreas; Nadig, Karin; Luechinger, Roger; Jäncke, Lutz

2012-07-01

Whether an agent receives positive task feedback or a monetary reward, neural activity in their striatum increases. In the latter case striatal activity reflects extrinsic reward processing, while in the former, striatal activity reflects the intrinsically rewarding effects of performing well. There can be a "hidden cost of reward", which is a detrimental effect of extrinsic on intrinsic reward value. This raises the question how these two types of reward interact. To address this, we applied a monetary incentive delay task: in all trials participants received feedback depending on their performance. In half of the trials they could additionally receive monetary reward if they performed well. This resulted in high performance trials, which were monetarily rewarded and high performance trials that were not. This made it possible to dissociate the neural correlates of performance feedback from the neural correlates of monetary reward that comes with high performance. Performance feedback alone elicits activation increases in the ventral striatum. This activation increases due to additional monetary reward. Neural response in the dorsal striatum on the other hand is only significantly increased by feedback when a monetary incentive is present. The quality of performance does not significantly influence dorsal striatum activity. In conclusion, our results indicate that the dorsal striatum is primarily sensitive to optional or actually received external rewards, whereas the ventral striatum may be coding intrinsic reward due to positive performance feedback. Thus the ventral striatum is suggested to be involved in the processing of intrinsically motivated behavior. Copyright © 2012 Elsevier Ltd. All rights reserved.

Dysphonia in performers: toward a clinical definition of laryngology of the performing voice.

PubMed

Guss, Joel; Sadoughi, Babak; Benson, Brian; Sulica, Lucian

2014-05-01

To identify causes of dysphonia in performers and compare causes and aspects of treatment of dysphonia in performers and nonperformers. Case-control study. A chart review of all new patients presenting with a chief complaint of dysphonia over a 1-year period was performed. The prevalence of laryngeal disorders was reviewed and differences between performers and nonperformers were analyzed. The odds ratio of the prevalence of each disorder was computed against performer status as a risk factor. Four hundred seventy-six new patients complaining of dysphonia presented over 12 months; 74 were vocal performers. The median duration of symptoms in performers was 90 days. Phonotraumatic lesions were significantly more prevalent in performers (63.5% vs. 28.6%, P < 0.001), particularly bilateral mid-fold swelling (4-fold increase in performers), pseudocysts (3-fold increase), and vocal fold hemorrhage/ectasia. Neurologic disorders (vocal fold paralysis and spasmodic dysphonia), neoplastic pathologies, and age-related phenomena (atrophy/presbyphonia) were significantly more common in nonperformers. Overall and diagnosis-specific rates of surgical intervention were equal between the two groups. Phonotraumatic injury is responsible for the majority of dysphonia in vocal performers, to a significantly greater extent than in nonperformers and requires the implementation of standard therapeutic strategies. Awareness of the specific risks and management needs of the performer is of paramount importance to the practice of laryngology of the performing voice. Copyright © 2014 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

Association of tracheal mucus or blood and airway neutrophilia with racing performance in Thoroughbred horses in an Australian racing yard.

PubMed

Salz, R O; Ahern, B J; Boston, R; Begg, L M

2016-04-01

To determine the variation of tracheal mucus scores, tracheal blood scores and transendoscopic tracheal wash (TW) cytology in a population of Thoroughbred (TB) racehorses and assess their association with racing performance. A total of 220 endoscopic examinations were performed and TWs obtained from 155 TB racehorses. Samples were collected 60-120 min following gallop work. Tracheal mucus score, tracheal blood score and TW cytology were analysed and their association with racing performance assessed. Of the total examinations and samples, 194 from 135 horses fitted the criteria for inclusion. The overall prevalence of visible tracheal mucus was 2.5% (5/194) and of increased tracheal mucus was 0%. The prevalence of visible tracheal blood was 8.8% (17/194) and of increased tracheal blood was 4.6% (9/194). A total of 36% (70/194) of TWs contained elevated percentages of neutrophils and of these, 96% (67/70) occurred in the absence of any visible tracheal mucus. There was no significant association between tracheal mucus score or TW cytology and subsequent racing performance. There was a statistically significant association (P = 0.004) between increased tracheal blood scores and poor racing performance. Visible tracheal blood seen after strenuous exercise in clinically normal TB racehorses was a risk factor for poor racing performance, but the presence of airway neutrophilia was not. No horses in this study were found to have increased tracheal mucus, so the association of increased tracheal mucus with racing performance could not be assessed. © 2016 Australian Veterinary Association.

Experimental study of the influence of flow passage subtle variation on mixed-flow pump performance

NASA Astrophysics Data System (ADS)

Bing, Hao; Cao, Shuliang

2014-05-01

In the mixed-flow pump design, the shape of the flow passage can directly affect the flow capacity and the internal flow, thus influencing hydraulic performance, cavitation performance and operation stability of the mixed-flow pump. However, there is currently a lack of experimental research on the influence mechanism. Therefore, in order to analyze the effects of subtle variations of the flow passage on the mixed-flow pump performance, the frustum cone surface of the end part of inlet contraction flow passage of the mixed-flow pump is processed into a cylindrical surface and a test rig is built to carry out the hydraulic performance experiment. In this experiment, parameters, such as the head, the efficiency, and the shaft power, are measured, and the pressure fluctuation and the noise signal are also collected. The research results suggest that after processing the inlet flow passage, the head of the mixed-flow pump significantly goes down; the best efficiency of the mixed-flow pump drops by approximately 1.5%, the efficiency decreases more significantly under the large flow rate; the shaft power slightly increases under the large flow rate, slightly decreases under the small flow rate. In addition, the pressure fluctuation amplitudes on both the impeller inlet and the diffuser outlet increase significantly with more drastic pressure fluctuations and significantly lower stability of the internal flow of the mixed-flow pump. At the same time, the noise dramatically increases. Overall speaking, the subtle variation of the inlet flow passage leads to a significant change of the mixed-flow pump performance, thus suggesting a special attention to the optimization of flow passage. This paper investigates the influence of the flow passage variation on the mixed-flow pump performance by experiment, which will benefit the optimal design of the flow passage of the mixed-flow pump.

Can formative quizzes predict or improve summative exam performance?*

PubMed Central

Zhang, Niu; Henderson, Charles N.R.

2015-01-01

Objective Despite wide use, the value of formative exams remains unclear. We evaluated the possible benefits of formative assessments in a physical examination course at our chiropractic college. Methods Three hypotheses were examined: (1) Receiving formative quizzes (FQs) will increase summative exam (SX) scores, (2) writing FQ questions will further increase SE scores, and (3) FQs can predict SX scores. Hypotheses were tested across three separate iterations of the class. Results The SX scores for the control group (Class 3) were significantly less than those of Classes 1 and 2, but writing quiz questions and taking FQs (Class 1) did not produce significantly higher SX scores than only taking FQs (Class 2). The FQ scores were significant predictors of SX scores, accounting for 52% of the SX score. Sex, age, academic degrees, and ethnicity were not significant copredictors. Conclusion Our results support the assertion that FQs can improve written SX performance, but students producing quiz questions didn't further increase SX scores. We concluded that nonthreatening FQs may be used to enhance student learning and suggest that they also may serve to identify students who, without additional remediation, will perform poorly on subsequent summative written exams. PMID:25517737

Innovation in internship preparation: an operative anatomy course increases senior medical students' knowledge and confidence.

PubMed

Tocco, Nikki; Brunsvold, Melissa; Kabbani, Loay; Lin, Jules; Stansfield, Brent; Mueller, Dean; Minter, Rebecca M

2013-08-01

An operative anatomy course was developed within the construct of a surgical internship preparatory curriculum. This course provided fourth-year medical students matching into a surgical residency the opportunity to perform intern-level procedures on cadavers under the guidance of surgical faculty members. Senior medical students performed intern-level procedures on cadavers with the assistance of faculty surgeons. Students' confidence, anxiety, and procedural knowledge were evaluated both preoperatively and postoperatively. Preoperative and postoperative data were compared both collectively and based on individual procedures. Student confidence and procedural knowledge significantly increased and anxiety significantly decreased when preoperative and postoperative data were compared (P < .05). Students reported moderate to significant improvement in their ability to perform a variety of surgical tasks. The consistent improvement in confidence, knowledge, and anxiety justifies further development of an operative anatomy course, with future assessment of the impact on performance in surgical residency. Copyright © 2013 Elsevier Inc. All rights reserved.

The role of mental rotation and memory scanning on the performance of laparoscopic skills: a study on the effect of camera rotational angle.

PubMed

Conrad, J; Shah, A H; Divino, C M; Schluender, S; Gurland, B; Shlasko, E; Szold, A

2006-03-01

The rotational angle of the laparoscopic image relative to the true horizon has an unknown influence on performance in laparoscopic procedures. This study evaluates the effect of increasing rotational angle on surgical performance. Surgical residents (group 1) (n = 6) and attending surgeons (group 2) (n = 4) were tested on two laparoscopic skills. The tasks consisted of passing a suture through an aperture, and laparoscopic knot tying. These tasks were assessed at 15 degrees intervals between 0 degrees and 90 degrees , on three consecutive repetitions. The participant's performance was evaluated based on the time required to complete the tasks and number of errors incurred. There was an increasing deterioration in suturing performance as the degree of image rotation was increased. Participants showed a statistically significant 20-120% progressive increase in time to completion of the tasks (p = 0.004), with error rates increasing from 10% to 30% (p = 0.04) as the angle increased from 0 degrees to 90 degrees. Knot-tying performance similarly showed a decrease in performance that was evident in the less experienced surgeons (p = 0.02) but with no obvious effect on the advanced laparoscopic surgeons. When evaluated independently and as a group, both novice and experienced laparoscopic surgeons showed significant prolongation to completion of suturing tasks with increased errors as the rotational angle increased. The knot-tying task shows that experienced surgeons may be able to overcome rotational effects to some extent. This is consistent with results from cognitive neuroscience research evaluating the processing of directional information in spatial motor tasks. It appears that these tasks utilize the time-consuming processes of mental rotation and memory scanning. Optimal performance during laparoscopic procedures requires that the rotation of the camera, and thus the image, be kept to a minimum to maintain a stable horizon. New technology that corrects the rotational angle may benefit the surgeon, decrease operating time, and help to prevent adverse outcomes.

Whey protein rich in alpha-lactalbumin increases the ratio of plasma tryptophan to the sum of the other large neutral amino acids and improves cognitive performance in stress-vulnerable subjects.

PubMed

Markus, C Rob; Olivier, Berend; de Haan, Edward H F

2002-06-01

Cognitive performance often declines under chronic stress exposure. The negative effect of chronic stress on performance may be mediated by reduced brain serotonin function. The uptake of the serotonin precursor tryptophan into the brain depends on nutrients that influence the availability of tryptophan by changing the ratio of plasma tryptophan to the sum of the other large neutral amino acids (Trp-LNAA ratio). In addition, a diet-induced increase in tryptophan may increase brain serotonergic activity levels and improve cognitive performance, particularly in high stress-vulnerable subjects. We tested whether alpha-lactalbumin, a whey protein with a high tryptophan content, would increase the plasma Trp-LNAA ratio and improve cognitive performance in high stress- vulnerable subjects. Twenty-three high stress-vulnerable subjects and 29 low stress-vulnerable subjects participated in a double-blind, placebo-controlled, crossover study. All subjects conducted a memory-scanning task after the intake of a diet enriched with either alpha-lactalbumin (alpha-lactalbumin diet) or sodium caseinate (control diet). Blood samples were taken to measure the effect of dietary manipulation on the plasma Trp-LNAA ratio. A significantly greater increase in the plasma Trp-LNAA ratio after consumption of the alpha-lactalbumin diet than after the control diet (P = 0.0001) was observed; memory scanning improved significantly only in the high stress-vulnerable subjects (P = 0.019). Because an increase in the plasma Trp-LNAA ratio is considered to be an indirect indication of increased brain serotonin function, the results suggest that dietary protein rich in alpha-lactalbumin improves cognitive performance in stress-vulnerable subjects via increased brain tryptophan and serotonin activities.

Effects of increasing time delays on pitch-matching accuracy in trained singers and untrained individuals.

PubMed

Estis, Julie M; Coblentz, Joana K; Moore, Robert E

2009-07-01

Trained singers (TS) generally demonstrate accurate pitch matching, but this ability varies within the general population. Pitch-matching accuracy, given increasing silence intervals of 5, 15, and 25 seconds between target tones and vocal matches, was investigated in TS and untrained individuals. A relationship between pitch discrimination and pitch matching was also examined. Thirty-two females (20-30 years) were grouped based on individual vocal training and performance in an immediate pitch-matching task. Participants matched target pitches following time delays, and completed a pitch discrimination task, which required the classification of two tones as same or different. TS and untrained accurate participants performed comparably on all pitch-matching tasks, while untrained inaccurate participants performed significantly less accurately than the other two groups. Performances declined across groups as intervals of silence increased, suggesting degradation of pitch matching as pitch memory was taxed. A significant relationship between pitch discrimination and pitch matching was revealed across participants.

[Effect of exhaustive weightlifting exercise on EMG, biochemical markers of muscle damage and performance capacity in young male subjects].

PubMed

Minigalin, A D; Shumakov, A R; Novozhilov, A V; Samsonova, A V; Kos'mina, E A; Kalinskiĭ, M I; Baranova, T I; Kubasov, I V; Morozov, V I

2015-01-01

The aim of this study was to examine the effect of exhaustive weightlifting exercise on electrical and biochemical variables and performance capacity in young male subjects. The onset of exercise (80-50% 1RM) was associated with a decrease in the amount of work performed, which was followed by a steady performance capacity at 40-10% 1RM. There were no significant changes of m. rectus femoris EMG maximal amplitude though it tended to be increased during the first half of exercise. A significant blood lactate concentration increase indicated that an anaerobic metabolism was a predominant mechanism of muscle contraction energy-supply. CK level in blood plasma did not change but plasma myoglobin concentration doubled immediately post-exercise. The data presented here suggest that decrease in performance capacity was likely due to progressive "refusal of work" of the fast motor units and work prolongation of weaker, intermediate and slow motor units. Unchangeable CK activity and relatively small increase in myoglobin concentration in plasma suggest that used weightlifting exercise did not induced substantial damage in myocytes' membranes in our subjects.

The effects of resistance training prioritization in NCAA Division I Football summer training.

PubMed

Smith, Robert A; Martin, Gerard J; Szivak, Tunde K; Comstock, Brett A; Dunn-Lewis, Courtenay; Hooper, David R; Flanagan, Shawn D; Looney, David P; Volek, Jeff S; Maresh, Carl M; Kraemer, William J

2014-01-01

Resistance training (RT) is an integral part of National Collegiate Athletic Association (NCAA) Division I Football performance programs. In the sport of football, there are several components that a strength and conditioning coach must be aware of. These include body mass, size, strength, power, speed, conditioning, and injury prevention, among others. The purpose of this study was to investigate if the RT component of a performance program could be prioritized for specific results using a nonlinear training model, grouping athletes by eligibility year. The NCAA Division I football student athletes were placed into 3 separate groups based on the playing year. All subjects participated in a 10-week, 4 days·week-1 off-season summer resistance training program. The training of group 1 (n = 20, age: 18.95 ± 0.76 years, height: 186.63 ± 7.21 cm, body mass: 97.66 ± 18.17 kg, playing year: 1.05 ± 0.22 years) prioritized hypertrophy-based RT to gain body mass. The training of group 2 (n = 20, age: 20.05 ± 1.05 years, height: 189.42 ± 5.49 cm, body mass: 106.99 ± 13.53 kg, and playing year: 2.35 ± 0.75 years) prioritized strength-based RT to gain strength. The training of group 3 (n = 20, age: 21.05 ± 1.10 years, height: 186.56 ± 6.73 cm, body mass: 109.8 ± 19.96 kg, playing year: 4.4 ± 0.50 years) prioritized power-based RT to gain power. Performance tests were evaluated during the first weeks of March (Spring) and August (Fall). The test measures included body mass (kilograms), 1-repetition maximum (1RM) bench press (kilograms), 1RM back squat (kilograms), 1RM power clean (kilograms), and countermovement vertical jump (CMVJ) height (centimeters). The primary findings of this investigation were as follows: group 1 saw significant increases in bench press maximum, back squat maximum, and power clean maximum (p ≤ 0.05). Group 2 saw significant increases in bench press maximum, back squat maximum, and power clean maximum (p ≤ 0.05). Group 3 saw a significant increase in power clean maximum (p ≤ 0.05). Group 1's significant increases were expected because of their low training age relatively shorter training history when compared with Groups 2 and 3. Group 1 did not see significant increases in body mass, with 7 out of 20 subjects being nonresponders. Group 2 and 3's significant increases were expected. Unexpectedly, no group saw significant increases in maximum CMVJ height. With so many factors that go into a football performance program contributing to football performance programing, it seems difficult to prioritize 1 RT goal over another without neglecting others during 10-week summer training program. Prioritization of strength appears to have the best overall affect on the RT portion of an off-season football performance program. Nonlinear periodization allows for the prioritization of 1 training goal without disregarding others with a smaller risk of neglecting other important components. This investigation showed that a performance program with a nonlinear model and prioritization on strength had produced the most desirable results.

Effects of Flexitime on Sick Leave, Vacation Leave, Anxiety, Performance, and Satisfaction in a Library Setting.

ERIC Educational Resources Information Center

Saunders, Carol Stoak; Saunders, Russell

1985-01-01

Results of study using pretest and posttest control group design in public university library setting to study impact of flexitime indicate that: satisfaction with promotions decreased with significant effect, sick leaves decreased, average length of vacation leaves increased, and results were mixed on performance and approached significance for…

Evaluation of left ventricular Tei index (index of myocardial performance) in healthy dogs and dogs with mitral regurgitation.

PubMed

Teshima, Kenji; Asano, Kazushi; Iwanaga, Koji; Koie, Hiroshi; Uechi, Masami; Kato, Yuka; Kutara, Kenji; Kanno, Nobuyuki; Seki, Mamiko; Edamura, Kazuya; Hasegawa, Atsuhiko; Tanaka, Shigeo

2007-02-01

The left ventricular (LV) Tei index (index of myocardial performance) has been demonstrated to be clinically useful in estimating comprehensive LV function, including the systolic and diastolic performances, in various human cardiac diseases. The purposes of this study were to validate the correlation between the LV Tei index and LV function obtained by cardiac catheterization in healthy dogs, and to evaluate the LV Tei index in dogs with naturally occurring mitral regurgitation (MR). In healthy dogs, the LV Tei index was significantly correlated with the LV peak +dP/dt (r = -0.89) and LV peak -dP/dt (r=0.87). The LV Tei index significantly increased in dogs with MR compared with normal dogs and significantly increased with progressively more severe clinical signs due to heart failure. The elevation of the LV Tei index in dogs with symptomatic MR appears to be associated with shortening of ejection time. The LV Tei index significantly increased with age and was not correlated with heart rate and body weight in normal dogs. In conclusion, our study demonstrated that the LV Tei index was measurable in dogs and not influenced by heart rate and body weight. The LV Tei index significantly increased with the progression of clinical signs in MR dogs. In particular, the elevation of the LV Tei index in dogs with symptomatic MR due to shortening of ejection time may suggest LV systolic dysfunction and the decrement of forward stroke volume.

The relationship of thoracic kyphosis to gait performance and quality of life in women with osteoporosis.

PubMed

Sangtarash, F; Manshadi, F D; Sadeghi, A

2015-08-01

Thoracic kyphosis angle (TKA) increases with osteoporosis. This study aimed to investigate the relationship between magnitude of TKA and quality of life and gait performance in 34 osteoporotic women. Our results suggest that increasing TKA is significantly associated with decreasing quality of life (r = -0.48, p < 0.005) and gait performance (r = -0.74, p < 0.0005). Osteoporosis and its related effects are threatening health and quality of life especially in postmenopausal women. Increased thoracic kyphosis angle (TKA), as one of the most common adverse musculoskeletal changes, could be regarded as a quantitative index for osteoporotic patients' assessment. Dual digital inclinometer (DDI) is one of the latest tools for non-invasive TKA measurement. The main purpose of this study was to determine whether a relationship existed between the magnitude of TKA, gait performance, and quality of life in a group of osteoporotic women. Thirty-four osteoporotic women, aged 50-68, participated in this descriptive analytic study. The magnitude of TKA measured by using DDI and expressed as the kyphosis index (KI). Quality of life and gait performance were assessed using short form 36 (SF36) questionnaire and functional gait assessment test, respectively. Back extension range of motion (ROM) and back extensor strength were also assessed. Pearson's correlation test was used to analyze the data, with the significance level of p < 0.05. The findings revealed a statistically significant negative correlation between KI and quality of life (r = -0.48, p < 0.005) and KI and gait performance (r = -0.74, p < 0.0005). There was also a significantly negative relation between KI and back extension ROM and back extensor strength (p < 0.05). The results of this study demonstrated that increased thoracic kyphosis negatively affects gait performance and quality of life. This finding could be regarded as an important implication for therapist to pay more attention to the magnitude of thoracic kyphosis angle and its changes, when selecting appropriate therapeutic methods to improve gait performance and quality of life in osteoporosis women.

Slow movement execution in event-related potentials (P300).

PubMed

Naruse, Kumi; Sakuma, Haruo; Hirai, Takane

2002-02-01

We examined whether slow movement execution has an effect on cognitive and information processing by measuring the P300 component. 8 subjects performed a continuous slow forearm rotational movement using 2 task speeds. Slow (a 30-50% decrease from the subject's Preferred speed) and Very Slow (a 60-80% decrease). The mean coefficient of variation for rotation speed under Very Slow was higher than that under Slow, showing that the subjects found it difficult to perform the Very Slow task smoothly. The EEG score of alpha-1 (8-10 Hz) under Slow Condition was increased significantly more than under the Preferred Condition; however, the increase under Very Slow was small when compared with Preferred. After performing the task. P300 latency under Very Slow increased significantly as compared to that at pretask. Further, P300 amplitude decreased tinder both speed conditions when compared to that at pretask, and a significant decrease was seen under the Slow Condition at Fz, whereas the decrease under the Very Slow Condition was small. These differences indicated that a more complicated neural composition and an increase in subjects' attention might have been involved when the task was performed under the Very Slow Condition. We concluded that slow movement execution may have an influence on cognitive function and may depend on the percentage of decrease from the Preferred speed of the individual.

Impact of single anaerobic exercise on delayed activation of endothelial xanthine oxidase in men and women.

PubMed

Wiecek, Magdalena; Maciejczyk, Marcin; Szymura, Jadwiga; Kantorowicz, Malgorzata; Szygula, Zbigniew

2017-11-01

The aim of the study was to evaluate the activity of xanthine oxidase (XO) in the blood of men and women during the first hour following a single anaerobic exercise (AN-EX), and after 24 hours of recovery, and to determine whether the changes in XO activity in the blood after AN-EX are dependent on anaerobic performance. Ten men and ten women performed a single AN-EX. Blood was collected before and five times after completion of the AN-EX. The activity of XO was determined. In both groups, a significant (P < 0.05) increase in blood XO activity was found only 24 hours after the AN-EX. The increased activity of XO in men was significantly lower than in women (P < 0.05). Negative correlations were found between the increase in XO activity in the blood plasma 24 hours after the AN-EX and anaerobic power, the total work performed during the AN-EX and the power decrease. In the first hour after the single AN-EX, XO activity in the blood of women and men did not change, but after 24 hours of recovery, it was significantly higher compared to baseline levels in both sexes. Single AN-EX causes a smaller increase in XO activity in people with higher anaerobic performance.

Is Double Metatarsal Osteotomy Superior to Proximal Chevron Osteotomy in Treatment of Hallux Valgus With Increased Distal Metatarsal Articular Angle?

PubMed

Park, Chul Hyun; Lee, Woo-Chun

We compared the results of proximal chevron osteotomy and double metatarsal osteotomy for hallux valgus with an increased distal metatarsal articular angle (DMAA). From October 2008 to December 2012, first metatarsal osteotomies were performed in 64 patients (69 feet) with symptomatic hallux valgus associated with an increased DMAA. Proximal chevron with Akin osteotomy and lateral soft tissue release was performed in 46 feet (PCO group); double metatarsal osteotomy and Akin osteotomy without lateral soft tissue release was performed in 23 feet (DMO group). Clinical assessments were performed using the American Orthopaedic Foot and Ankle Society (AOFAS) scale and visual analog scale (VAS). The hallux valgus angles, intermetatarsal angles, sesamoid positions, metatarsus adductus angles, and DMAAs were compared at different postoperative times. Postoperative shortening of first the metatarsal and complications were compared. The mean AOFAS scale and VAS scores showed significant improvement in both groups after surgery; however, no significant difference was observed between the 2 groups. The immediate postoperative hallux valgus angle and sesamoid position were significantly larger in DMO group; however, no intergroup difference was observed at the last follow-up visit, with the hallux valgus angle gradually increasing in the PCO group. The postoperative DMAA was significantly smaller in the DMO group. The mean shortening of the first metatarsal after surgery was significantly larger in the DMO group than in the PCO group. Transfer metatarsalgia developed in 1 foot (2.2%) in the PCO group and 2 feet (8.7%) in the DMO group. Partial avascular necrosis of the metatarsal head with advanced arthritis of the first metatarsophalangeal joint developed in 1 foot (4.3%) in the DMO group. In conclusion, no differences in the clinical and radiographic results were observed between the 2 groups for hallux valgus deformity with an increased DMAA. Copyright © 2017 The American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

Neurofeedback training for peak performance.

PubMed

Graczyk, Marek; Pąchalska, Maria; Ziółkowski, Artur; Mańko, Grzegorz; Łukaszewska, Beata; Kochanowicz, Kazimierz; Mirski, Andrzej; Kropotov, Iurii D

2014-01-01

One of the applications of the Neurofeedback methodology is peak performance in sport. The protocols of the neurofeedback are usually based on an assessment of the spectral parameters of spontaneous EEG in resting state conditions. The aim of the paper was to study whether the intensive neurofeedback training of a well-functioning Olympic athlete who has lost his performance confidence after injury in sport, could change the brain functioning reflected in changes in spontaneous EEG and event related potentials (ERPs). The case is presented of an Olympic athlete who has lost his performance confidence after injury in sport. He wanted to resume his activities by means of neurofeedback training. His QEEG/ERP parameters were assessed before and after 4 intensive sessions of neurotherapy. Dramatic and statistically significant changes that could not be explained by error measurement were observed in the patient. Neurofeedback training in the subject under study increased the amplitude of the monitoring component of ERPs generated in the anterior cingulate cortex, accompanied by an increase in beta activity over the medial prefrontal cortex. Taking these changes together, it can be concluded that that even a few sessions of neurofeedback in a high performance brain can significantly activate the prefrontal cortical areas associated with increasing confidence in sport performance.

Neural basis of stereotype-induced shifts in women's mental rotation performance

PubMed Central

Helt, Molly; Jacobs, Emily; Sullivan, Kerry

2007-01-01

Recent negative focus on women's academic abilities has fueled disputes over gender disparities in the sciences. The controversy derives, in part, from women's relatively poorer performance in aptitude tests, many of which require skills of spatial reasoning. We used functional magnetic imaging to examine the neural structure underlying shifts in women's performance of a spatial reasoning task induced by positive and negative stereotypes. Three groups of participants performed a task involving imagined rotations of the self. Prior to scanning, the positive stereotype group was exposed to a false but plausible stereotype of women's superior perspective-taking abilities; the negative stereotype group was exposed to the pervasive stereotype that men outperform women on spatial tasks; and the control group received neutral information. The significantly poorer performance we found in the negative stereotype group corresponded to increased activation in brain regions associated with increased emotional load. In contrast, the significantly improved performance we found in the positive stereotype group was associated with increased activation in visual processing areas and, to a lesser degree, complex working memory processes. These findings suggest that stereotype messages affect the brain selectively, with positive messages producing relatively more efficient neural strategies than negative messages. PMID:18985116

Neural basis of stereotype-induced shifts in women's mental rotation performance.

PubMed

Wraga, Maryjane; Helt, Molly; Jacobs, Emily; Sullivan, Kerry

2007-03-01

Recent negative focus on women's academic abilities has fueled disputes over gender disparities in the sciences. The controversy derives, in part, from women's relatively poorer performance in aptitude tests, many of which require skills of spatial reasoning. We used functional magnetic imaging to examine the neural structure underlying shifts in women's performance of a spatial reasoning task induced by positive and negative stereotypes. Three groups of participants performed a task involving imagined rotations of the self. Prior to scanning, the positive stereotype group was exposed to a false but plausible stereotype of women's superior perspective-taking abilities; the negative stereotype group was exposed to the pervasive stereotype that men outperform women on spatial tasks; and the control group received neutral information. The significantly poorer performance we found in the negative stereotype group corresponded to increased activation in brain regions associated with increased emotional load. In contrast, the significantly improved performance we found in the positive stereotype group was associated with increased activation in visual processing areas and, to a lesser degree, complex working memory processes. These findings suggest that stereotype messages affect the brain selectively, with positive messages producing relatively more efficient neural strategies than negative messages.

Weapons and Tactics Instructor Course 2-16 Sleep and Performance Study

DTIC Science & Technology

2017-03-01

assessments showed a significant increase in self-reported fatigue as the course progressed. This thesis outlines a detailed methodology and lessons...increase in self-reported fatigue as the course progressed. This thesis outlines a detailed methodology and lessons learned for follow-on studies of...Performance as a Result of Insufficient Sleep .........23  III.  METHODOLOGY

Performance improvement of ERP-based brain-computer interface via varied geometric patterns.

PubMed

Ma, Zheng; Qiu, Tianshuang

2017-12-01

Recently, many studies have been focusing on optimizing the stimulus of an event-related potential (ERP)-based brain-computer interface (BCI). However, little is known about the effectiveness when increasing the stimulus unpredictability. We investigated a new stimulus type of varied geometric pattern where both complexity and unpredictability of the stimulus are increased. The proposed and classical paradigms were compared in within-subject experiments with 16 healthy participants. Results showed that the BCI performance was significantly improved for the proposed paradigm, with an average online written symbol rate increasing by 138% comparing with that of the classical paradigm. Amplitudes of primary ERP components, such as N1, P2a, P2b, N2, were also found to be significantly enhanced with the proposed paradigm. In this paper, a novel ERP BCI paradigm with a new stimulus type of varied geometric pattern is proposed. By jointly increasing the complexity and unpredictability of the stimulus, the performance of an ERP BCI could be considerably improved.

Effect of wrist cooling on aerobic and anaerobic performance in elite sportsmen.

PubMed

Krishnan, Anup; Singh, Krishan; Sharma, Deep; Upadhyay, Vivekanand; Singh, Amit

2018-01-01

Body cooling has been used to increase sporting performance and enhance recovery. Several studies have reported improvement in exercise capacities using forearm and hand cooling or only hand cooling. Wrist cooling has emerged as a portable light weight solution for precooling prior to sporting activity. The Astrand test for aerobic performance and the Wingate test for anaerobic performance are reliable and accurate tests for performance assessment. This study conducted on elite Indian athletes analyses the effects of wrist precooling on aerobic and anaerobic performance as tested by the Astrand test and the Wingate test before and after wrist precooling. 67 elite sportsmen were administered Wingate and Astrand test under standardised conditions with and without wrist precooling using a wrist cooling device (dhamaSPORT). Paired t -test was applied to study effect on aerobic [VO 2 (ml/min/kg)] and anaerobic performance [peak power (W/kg) and average power (W/kg)] and Cohen's d was used to calculate effect size of wrist precooling. After wrist precooling, significant increase of 0.22 ( p  = 0.014, 95% CI: 0.047, 0.398) in peak power (W/kg) and 0.22 ( p  < 0.0001, 95% CI: 0.142, 0.291) was observed in average power (W/kg). Although, an increase of 1.38 ( p  = 0.097, 95% CI: -0.225, 3.012) was observed in VO 2 (ml/min/kg), wrist precooling was not significantly effective in aerobic performance. Wrist cooling effect size was smaller in VO 2 (Cohen's d  = 0.21), peak power (Cohen's d  = 0.31) and it was larger in average power (Cohen's d  = 0.71). Results show wrist precooling significantly improves anaerobic than aerobic performance of elite sportsmen.

Effects of visual feedback balance training on the balance and ankle instability in adult men with functional ankle instability.

PubMed

Nam, Seung-Min; Kim, Kyoung; Lee, Do Youn

2018-01-01

[Purpose] This study examined the effects of visual feedback balance training on the balance and ankle instability in adult men with functional ankle instability. [Subjects and Methods] Twenty eight adults with functional ankle instability, divided randomly into an experimental group, which performed visual feedback balance training for 20 minutes and ankle joint exercises for 10 minutes, and a control group, which performed ankle joint exercise for 30 minutes. Exercises were completed three times a week for 8 weeks. Bio rescue was used for balance ability. It measured limit of stability at one minute. For ankle instability was measured using Cumberland ankle instability tool (CAIT). This measure was performed before and after the experiments in each group. [Results] The experimental group had significant increase in the Limit of Stability and CAIT score. The control group had significant increase in CAIT score. While the Limit of Stability increased without significance. [Conclusion] In conclusion, visual feedback balance training can be recommended as a treatment method for patients with functional ankle instability.

Effect of central hypothyroidism on Doppler-derived myocardial performance index.

PubMed

Doin, Fabio Luiz Casanova; Borges, Mariana da Rosa; Campos, Orlando; de Camargo Carvalho, Antonio Carlos; de Paola, Angelo Amato Vincenzo; Paiva, Marcelo Goulart; Abucham, Julio; Moises, Valdir Ambrosio

2004-06-01

Myocardial performance index (MPI) has been used to assess global ventricular function in different types of cardiac disease. Thyroid hormones influence cardiac performance directly and indirectly by changes in peripheral circulation. The aim of this study was to evaluate the possible effect of central hypothyroidism (CH) on MPI. The study included 28 control subjects and 7 patients with CH without cardiac disease. MPI was defined as the sum of isovolumetric contraction time (ICT) and isovolumetric relaxation time divided by ejection time. Patients were submitted to hormonal therapy with thyroxin and the study was repeated after 35 to 42 days. MPI was significantly higher in patients with CH (0.54 +/- 0.08) than in control subjects (0.40 +/- 0.05) (P =.002). The increase in MPI was caused by the prolongation of ICT without a significant variation of isovolumetric relaxation time and ejection time. After hormonal therapy there was a significant reduction of MPI (0.54 +/- 0.08 vs 0.42 +/- 0.07; P =.028) and ICT. MPI was increased in patients with untreated CH. The increase was related to prolongation of ICT and reverted by hormonal therapy.

Plyometric jumping performances of male and female gymnasts from different heights.

PubMed

Marina, Michel; Jemni, Monèm; Rodríguez, Ferran A; Jimenez, Alfonso

2012-07-01

The objective of this study was to investigate and compare the factors influencing plyometric jumping performance between well-trained gymnasts and a control group. Seventy-six gymnasts and 91 moderately active subjects volunteered to participate in this study. Drop jumps (DJ) were performed from 20-, 40-, 60-, 80-, and 100-cm heights. Flight time (FT) and contact time (CT) were recorded using contact mat. Flight time to contact time (FC) ratio and Bosco expression (BE) were calculated. Male gymnasts scored similar FT to their controls, whereas female gymnasts had significantly longer FT compared with their peers. The gymnasts obtained significantly shorter CT than their control groups, whereas their FC ratios were significantly higher and increased when the height of the drops was close to 60 cm. Moreover, gymnasts' BE was greater in comparison to their respective control groups independent of the drop height. The height of the drop that produced the best FC ratio and BE varied between the groups. The best performances were obtained between 40- and 60-cm drop height for both groups. Female control group showed a trend toward a continuing decline with the increase of the drop height. The best gymnasts (finalists at World Championships) obtained their best performance at 80-cm drop. Flight time is the less discriminating factor distinguishing gymnasts' DJ performances. Considering CT, FC, and BE results all together could better profile the gymnasts rather than taken separately. Bosco expression was shown to be more sensitive to the increase in FT; we suggest BE as the best criteria to assess the appropriate drop height for plyometric training purposes in gymnasts as it has been significantly correlated to FT.

Effects of nutrition level of concentrate-based diets on growth performance and carcass characteristics of Hainan black goats.

PubMed

Wang, Dingfa; Zhou, Luli; Zhou, Hanlin; Hou, Guanyu; Li, Mao; Shi, Liguang; Huang, Xianzhou; Guan, Song

2014-06-01

This study assessed the effects of different nutrition levels of diets on growth performance and carcass characteristics of Hainan black goat. Twenty-four goats were divided into six diet treatments, which consisted of two levels of crude protein (CP; 15 and 17 %) and three levels of digestive energy (DE; 11.72, 12.55, and 13.39 MJ/kg). The results revealed that 17 % CP significantly (P < 0.05) increased ADG and improved FCR compared with 15 % CP. Therefore, the CP levels of diet affected growth performance. CP and DE levels in the diet had no significant effects (P > 0.05) on carcass characteristics of the goats. The mRNA expression levels of insulin-like growth factor 1 in muscle tissues increased with increasing CP and DE levels (P < 0.05).

Training our Future Endocrine Surgeons: A Look at the Endocrine Surgery Operative Experience of U.S. Surgical Residents

PubMed Central

Zarebczan, Barbara; Rajamanickam, Victoria; Leverson, Glen; Chen, Herbert; Sippel, Rebecca S

2010-01-01

Background Over the last 10 years the number of endocrine procedures performed in the US has increased significantly. We sought to determine if this has translated into an increase in operative volume for general surgery and otolaryngology residents. Method We evaluated records from the Resident Statistic Summaries of the RRC for US general surgery and otolaryngology residents for the years 2004-2008, specifically examining data on thyroidectomies and parathyroidectomies. Results Between 2004 and 2008, the average endocrine case volume of US general surgery and otolaryngology residents increased by approximately 15%, but otolaryngology residents performed over twice as many operations as US general surgery residents. The growth in case volume was mostly due to increases in the number of thyroidectomies performed by US general surgery and otolaryngology residents (17.9 to 21.8, p=0.007 and 46.5 to 54.4, p=0.04). Overall, otolaryngology residents also performed more parathyroidectomies than their general surgery counterparts (11.6 vs. 8.8, p=0.007). Conclusion Although there has been an increase in the number of endocrine cases performed by graduating US general surgery residents, this is significantly smaller than that of otolaryngology residents. In order to remain competitive, general surgery residents wishing to practice endocrine surgery may need to pursue additional fellowship training. PMID:21134536

Training our future endocrine surgeons: a look at the endocrine surgery operative experience of U.S. surgical residents.

PubMed

Zarebczan, Barbara; McDonald, Robert; Rajamanickam, Victoria; Leverson, Glen; Chen, Herbert; Sippel, Rebecca S

2010-12-01

During the last 10 years, the number of endocrine procedures performed in the United States has increased significantly. We sought to determine whether this has translated into an increase in operative volume for general surgery and otolaryngology residents. We evaluated records from the Resident Statistic Summaries of the Residency Review Committee (RRC) for U.S. general surgery and otolaryngology residents for the years 2004-2008, specifically examining data on thyroidectomies and parathyroidectomies. Between 2004 and 2008, the average endocrine case volume of U.S. general surgery and otolaryngology residents increased by approximately 15%, but otolaryngology residents performed more than twice as many operations as U.S. general surgery residents. The growth in case volume was mostly from increases in the number of thyroidectomies performed by U.S. general surgery and otolaryngology residents (17.9 to 21.8, P = .007 and 46.5 to 54.4, P = .04). Overall, otolaryngology residents also performed more parathyroidectomies than their general surgery counterparts (11.6 vs 8.8, P = .007). Although there has been an increase in the number of endocrine cases performed by graduating U.S. general surgery residents, this is significantly smaller than that of otolaryngology residents. To remain competitive, general surgery residents wishing to practice endocrine surgery may need to pursue additional fellowship training. Copyright © 2010 Mosby, Inc. All rights reserved.

Deep learning for hybrid EEG-fNIRS brain–computer interface: application to motor imagery classification

NASA Astrophysics Data System (ADS)

Chiarelli, Antonio Maria; Croce, Pierpaolo; Merla, Arcangelo; Zappasodi, Filippo

2018-06-01

Objective. Brain–computer interface (BCI) refers to procedures that link the central nervous system to a device. BCI was historically performed using electroencephalography (EEG). In the last years, encouraging results were obtained by combining EEG with other neuroimaging technologies, such as functional near infrared spectroscopy (fNIRS). A crucial step of BCI is brain state classification from recorded signal features. Deep artificial neural networks (DNNs) recently reached unprecedented complex classification outcomes. These performances were achieved through increased computational power, efficient learning algorithms, valuable activation functions, and restricted or back-fed neurons connections. By expecting significant overall BCI performances, we investigated the capabilities of combining EEG and fNIRS recordings with state-of-the-art deep learning procedures. Approach. We performed a guided left and right hand motor imagery task on 15 subjects with a fixed classification response time of 1 s and overall experiment length of 10 min. Left versus right classification accuracy of a DNN in the multi-modal recording modality was estimated and it was compared to standalone EEG and fNIRS and other classifiers. Main results. At a group level we obtained significant increase in performance when considering multi-modal recordings and DNN classifier with synergistic effect. Significance. BCI performances can be significantly improved by employing multi-modal recordings that provide electrical and hemodynamic brain activity information, in combination with advanced non-linear deep learning classification procedures.

A longitudinal study of childhood obesity, weight status change, and subsequent academic performance in Taiwanese children.

PubMed

Chen, Li-Jung; Fox, Kenneth R; Ku, Po-Wen; Wang, Ching-Hui

2012-09-01

This study examined the association among childhood obesity, weight status change, and subsequent academic performance at 6-year follow-up. First-grade students from one elementary school district in Taichung City, Taiwan were followed for 6 years (N = 409). Academic performance was extracted from the school records at the end of each grade. Weight and height were measured at the beginning of each grade. A weight change variable was created based on each child's weight status difference at grades 1 and 6. A multivariate linear regression model for predicting academic performance at grade 6 was developed with adjustment for individual characteristics and family factors. A latent growth curve (LGC) showed the association between changes in body mass index (BMI) and in academic performance across a 6-year period. BMI in children increased significantly across 6 years. The rate of increase in BMI over 6 years was higher for children with higher baseline BMIs than it was for children with lower baseline BMIs. However, BMI changes were not significantly associated with changes of academic performance. There was no significant relationship between initial obesity or change in weight status and subsequent academic performance. It appears that either being or becoming overweight/obese did not impact academic achievement for these Taiwanese children. © 2012, American School Health Association.

Entrepreneurship Education and Academic Performance

ERIC Educational Resources Information Center

Johansen, Vegard

2014-01-01

The significant increase of entrepreneurship education (EE) is a trend in Europe. Entrepreneurship education is supposed to promote general and specific entrepreneurial abilities and improve academic performance. This paper evaluates whether EE influences academic performance, measured by Grade Point Average. The main indicator used for EE is the…

Disfluent presentations lead to the creation of more false memories.

PubMed

Sanchez, Christopher A; Naylor, Jamie S

2018-01-01

The creation of false memories within the Deese-Roediger-McDermott (DRM) paradigm has been shown to be sensitive to many factors such as task instructions, participant mood, or even presentation modality. However, do other simple perceptual differences also impact performance on the DRM and the creation of false memories? This study explores the potential impact of changes in perceptual disfluency on DRM performance. To test for a potential influence of disfluency on false memory creation, participants viewed lists under either perceptually disfluent conditions or not. Results indicated that disfluency did significantly impact performance in the DRM paradigm; more disfluent presentations significantly increased the recall and recognition of unpresented information, although they did not impact recall or recognition of presented information. Thus, although disfluency did impact performance, disfluency did not produce a positive benefit related to overall task performance. This finding instead suggests that more disfluent presentations can increase the likelihood that false memories are created, and provide little positive performance benefit.

Disfluent presentations lead to the creation of more false memories

PubMed Central

Naylor, Jamie S.

2018-01-01

The creation of false memories within the Deese-Roediger-McDermott (DRM) paradigm has been shown to be sensitive to many factors such as task instructions, participant mood, or even presentation modality. However, do other simple perceptual differences also impact performance on the DRM and the creation of false memories? This study explores the potential impact of changes in perceptual disfluency on DRM performance. To test for a potential influence of disfluency on false memory creation, participants viewed lists under either perceptually disfluent conditions or not. Results indicated that disfluency did significantly impact performance in the DRM paradigm; more disfluent presentations significantly increased the recall and recognition of unpresented information, although they did not impact recall or recognition of presented information. Thus, although disfluency did impact performance, disfluency did not produce a positive benefit related to overall task performance. This finding instead suggests that more disfluent presentations can increase the likelihood that false memories are created, and provide little positive performance benefit. PMID:29370255

Functional neuroanatomy of sustained memory encoding performance in healthy aging and in Alzheimer's disease.

PubMed

Weis, Susanne; Leube, Dirk; Erb, Michael; Heun, Reinhard; Grodd, Wolfgang; Kircher, Tilo

2011-07-01

The aim of our study was to examine brain networks involved with sustaining memory encoding performance in healthy aging and in Alzheimer's disease (AD). Since different brain regions are affected by degradation in these two conditions, it might be conceivable that different compensation mechanisms occur to keep up memory performance in aging and in AD. Using an event-related functional magnetic resonance imaging (FMRI) design and a correlation analysis, 8 patients suffering from AD and 29 elderly control subjects were scanned while they studied a list of words for a subsequent memory test. Individual performance was assessed on the basis of a subsequent recognition test, and brain regions were identified where functional activations during study correlated with memory performance. In both groups, successful memory encoding performance was significantly correlated with the activation of the right frontal cortex. Furthermore, in healthy controls, there was a significant correlation of memory performance and the activation of the left medial and lateral temporal lobe. In contrast, in AD patients, increasing memory performance goes along with increasing activation of the hippocampus and a bilateral brain network including the frontal and temporal cortices. Our data show that in healthy aging and in AD, common and distinct compensatory mechanisms are employed to keep up a certain level of memory performance. Both in healthy aging and in patients with AD, an increased level of monitoring and control processes mediated by the (right) frontal lobe seems to be necessary to maintain a certain level of memory performance. In addition, memory performance in healthy older subjects seems to rely on an increased effort in encoding item-specific semantic and contextual information in lateral areas of the (left) temporal lobe. In AD patients, on the other hand, the maintenance of memory performance is related to an increase of activation of the (left) hippocampus in conjunction with a bilateral network of cortical areas that might be involved with phonological and visual rehearsal of the incoming information.

The interacting effect of cognitive and motor task demands on performance of gait, balance and cognition in young adults.

PubMed

Szturm, Tony; Maharjan, Pramila; Marotta, Jonathan J; Shay, Barbara; Shrestha, Shiva; Sakhalkar, Vedant

2013-09-01

Mobility limitations and cognitive impairments, each common with aging, reduce levels of physical and mental activity, are prognostic of future adverse health events, and are associated with an increased fall risk. The purpose of this study was to examine whether divided attention during walking at a constant speed would decrease locomotor rhythm, stability, and cognitive performance. Young healthy participants (n=20) performed a visuo-spatial cognitive task in sitting and while treadmill walking at 2 speeds (0.7 and 1.0 m/s).Treadmill speed had a significant effect on temporal gait variables and ML-COP excursion. Cognitive load did not have a significant effect on average temporal gait variables or COP excursion, but variation of gait variables increased during dual-task walking. ML and AP trunk motion was found to decrease during dual-task walking. There was a significant decrease in cognitive performance (success rate, response time and movement time) while walking, but no effect due to treadmill speed. In conclusion walking speed is an important variable to be controlled in studies that are designed to examine effects of concurrent cognitive tasks on locomotor rhythm, pacing and stability. Divided attention during walking at a constant speed did result in decreased performance of a visuo-spatial cognitive task and an increased variability in locomotor rhythm. Copyright © 2013 Elsevier B.V. All rights reserved.

Evolving indications for and trends in keratoplasty in British Columbia, Canada, from 2002 to 2011: a 10-year review.

PubMed

Tan, Johnson C H; Holland, Simon P; Dubord, Paul J; Moloney, Gregory; McCarthy, Martin; Yeung, Sonia N

2014-03-01

The aim of this study was to report the evolving indications for keratoplasty and the shift in the type of keratoplasty performed in British Columbia, Canada, over a 10-year period from 2002 to 2011. This was a retrospective database review of all the records of corneal transplant tissues at the Eye Bank of British Columbia, Canada, from January 2002 to December 2011. The patient demographics, indications, and types of transplant performed were analyzed. A total of 4843 corneal transplants were performed in 3742 patients (1968 male and 1774 female) from January 2002 to December 2011. The number of keratoplasties performed ranged from 420 in 2008 to 578 in 2011. The top 4 indications over the 10-year period were Fuchs endothelial dystrophy (FED; 18.9%), aphakic/pseudophakic bullous keratopathy (17.4%), regraft (17.1%), and keratoconus (15.5%). Penetrating keratoplasty (PKP) accounted for 86.5% (4191 transplants) of all keratoplasties performed. Since the introduction of Descemet stripping automated endothelial keratoplasty (DSAEK) in 2007, there was a significant increase in the number of DSAEKs (P < 0.0001) performed and a statistical decline in the number of PKPs (P < 0.0001) performed. Despite only 30 deep anterior lamellar keratoplasties being performed, an increasing trend was observed after 2008 (P = 0.0087). A decreasing trend in PKPs and an increasing trend in DSAEKs were observed for surgeries performed for FED, aphakic/pseudophakic bullous keratopathy, and regraft. FED has become the top indication for performing a keratoplasty over the 10-year period. There was a shift from PKP to DSAEK performed for endothelial failure. Although the number of deep anterior lamellar keratoplasty surgeries was small, there was a significant increasing trend.

Specificity of endurance, sprint and strength training on physical performance capacity in young athletes.

PubMed

Häkkinen, K; Mero, A; Kauhanen, H

1989-03-01

Three prebubescent athlete groups of endurance runners (E; n = 4), sprinters (S; n = 4) and weightlifters (WL; n = 4) and one control group (C; n = 6) as well as one junior but postpubescent weightlifter group (JWL; n = 6) volunteered as subjects in order to investigate specific effects of endurance, sprint and strength training on physical performance capacity during a 1 year follow-up period. The prepubescent E-group had higher (p less than 0.05) VO2 max (66.5 +/- 2.9 ml x kg1 x min-1) already at the beginning of the study than the other three groups. The prepubescent WL-group demonstrated greater (p less than 0.05) maximal muscular strength than the E-group and the WL-group increased its strength greatly by 21.4% (p less than 0.05) during the follow-up. No significant differences were observed in physical performance capacity between the prepubescent WL- and S-groups. Both groups demonstrated a slightly (ns.) better force-time curve recorded from the leg extensor muscles than the E-group and significant (p less than 0.05) increases occurred in these two groups in dynamic explosive performance during the follow-up. The postpubescent JWL-group demonstrated much greater (p less than 0.001) muscular mass and maximal strength than the prepubescent groups. No significant changes occurred in explosive types of performances in these athletes but significant (p less than 0.05) increase took place in the maximal neural activation and strength of the leg extensor muscles during the 1 year.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of creatine supplementation on exercise performance.

PubMed

Demant, T W; Rhodes, E C

1999-07-01

While creatine has been known to man since 1835, when a French scientist reported finding this constitutent of meat, its presence in athletics as a performance enhancer is relatively new. Amid claims of increased power and strength, decreased performance time and increased muscle mass, creatine is being hailed as a true ergogenic aid. Creatinine is synthesised from the amino acids glycine, arginine and methionine in the kidneys, liver and pancreas, and is predominantly found in skeletal muscle, where it exists in 2 forms. Approximately 40% is in the free creatine form (Crfree), while the remaining 60% is in the phosphorylated form, creatine phosphate (CP). The daily turnover rate of approximately 2 g per day is equally met via exogenous intake and endogenous synthesis. Although creatine concentration (Cr) is greater in fast twitch muscle fibres, slow twitch fibres have a greater resynthesis capability due to their increased aerobic capacity. There appears to be no significant difference between males and females in Cr, and training does not appear to effect Cr. The 4 roles in which creatine is involved during performance are temporal energy buffering, spatial energy buffering, proton buffering and glycolysis regulation. Creatine supplementation of 20 g per day for at least 3 days has resulted in significant increases in total Cr for some individuals but not others, suggesting that there are 'responders' and 'nonresponders'. These increases in total concentration among responders is greatest in individuals who have the lowest initial total Cr, such as vegetarians. Increased concentrations of both Crfree and CP are believed to aid performance by providing more short term energy, as well as increase the rate of resynthesis during rest intervals. Creatine supplementation does not appear to aid endurance and incremental type exercises, and may even be detrimental. Studies investigating the effects of creatine supplementation on short term, high intensity exercises have reported equivocal results, with approximately equal numbers reporting significant and nonsignificant results. The only side effect associated with creatine supplementation appears to be a small increase in body mass, which is due to either water retention or increased protein synthesis.

Reduced exercise time in competitive simulations consequent to low level ozone exposure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schelegle, E.S.; Adams, W.C.

Ten highly trained endurance athletes were studied to determine the effects of exposure to low ozone (O/sub 3/) concentrations on simulated competitive endurance performance and associated physiological and subjective symptom responses. Each subject was randomly exposed to filtered air (FA), and to 0.12, 0.18, and 0.24 ppm O/sub 3/ while performing a 1 h competitive simulation protocol on a bicycle ergometer. Endurance performance was evaluated by the number of subjects unable to complete rides (last 30 min at an intense work load of approximately 86% VO/sub 2/max). All subjects completed the FA exposure, whereas one, five, and seven subjects didmore » not complete the 0.12, 0.18, and 0.24 ppm O/sub 3/ exposures, respectively. Statistical analysis indicated a significant (P less than 0.05) increase in the inability of subjects to complete the competitive simulations with increasing O/sub 3/ concentration, including a significant difference between the 0.24 ppm O/sub 3/ and FA exposure. Significant decreases (P less than 0.05) were also observed following the 0.18 and 0.24 ppm O/sub 3/ exposures, respectively, in forced vital capacity (-7.8 and -9.9%), and forced expiratory volume in 1 s (-5.8 and -10.5%). No significant O/sub 3/ effect was observed for exercise respiratory metabolism or ventilatory pattern responses. However, the number of reported subjective symptoms increased significantly following the 0.18 and 0.24 ppm O/sub 3/ protocols. These data demonstrate significant decrements in simulated competitive endurance performance and in pulmonary function, with accompanying enhanced subjective symptoms, following exposure to low O/sub 3/ levels commonly observed in numerous metropolitan environments during the summer months.« less

The effect of vitamins C and e supplementation on muscle damage, performance, and body composition in athlete women: a clinical trial.

PubMed

Taghiyar, Maryam; Ghiasvand, Reza; Askari, Gholamreza; Feizi, Awat; Hariri, Mitra; Mashhadi, Nafiseh Shokri; Darvishi, Leila

2013-04-01

Due to the special training conditions and lifestyle athletes require an antioxidant system that is more efficient than others. To keep this system optimal, many of them use antioxidant supplements. This study aimed to investigate the effects of vitamins C and E supplementation on muscle damage, performance, and body composition in athlete women. The study was a 4-week randomized, double-blind clinical trial conducted on 64 trained female athletes recruited in Isfahan sports club. They were randomly assigned to one of the following four groups; A: vitamin C (250 mg/day), B: vitamin E (400 IU), C: vitamin C + vitamin E and control (placebo). Harvard Step Test was used to measure maximal oxygen consumption for performance, body composition, and damage marker (myoglobin) were measured before and after the intervention. Comparing the result of the test in performance of sport, there was no significant difference between groups in VO2 max. Also, vitamin supplements had no significant effect on subcutaneous fat between the groups, however, in the intergroup comparison, were significantly increased in group control (P = 0.03). But, there were no significant differences, change in myoglobin between the groups. There was a significant increase in group A (P = 0.04). Vitamins C and E supplementation had no significant effect on any of the studied parameters.

UV-catalytic treatment of spent caustic from ethene plant with hydrogen peroxide and ozone oxidation.

PubMed

Yu, Zheng-zhe; Sun, De-zhi; Li, Chang-hai; Shi, Peng-fei; Duan, Xiao-dong; Sun, Guo-rong; Liu, Jun-xin

2004-01-01

The performance of UV/H2O2, UV/O3 and UV/H2O2/O3 oxidation systems for treating spent caustic from an ethylene plant was investigated. In UV/H2O2 system, with the increase of H2O2 dosage, removal efficiencies of COD and the ratio of biochemical oxygen demand (BOD) to chemical oxygen demand (COD) of the effluent were increased and a better performance was obtained than the H2O2 system alone. In UV/H2O2 system, removal efficiency of COD reach 68% under the optimum condition, and BOD/COD ratio was significantly increased from 0.22 to 0.52. In UV/O3 system, with the increase of O3 dosage, removal efficiency of COD and BOD/COD ratio were increased, and a better performance was obtained than the O3 system alone. Under the optimum condition, removal efficiency of COD was 54%, and BOD/COD ratio was significantly increased from 0.22 to 0.48. In UV/H2O2/O3 system, COD removal efficiency was found to be 22.0% higher than UV/O3 system.

Short-Term Effects of Chewing on Task Performance and Task-Induced Mydriasis: Trigeminal Influence on the Arousal Systems

PubMed Central

Tramonti Fantozzi, Maria Paola; De Cicco, Vincenzo; Barresi, Massimo; Cataldo, Enrico; Faraguna, Ugo; Bruschini, Luca; Manzoni, Diego

2017-01-01

Trigeminal input to the ascending activating system is important for the maintenance of arousal and may affect the discharge of the noradrenergic neurons of the locus coeruleus (LC), whose activity influences both vigilance state and pupil size, inducing mydriasis. For this reason, pupil size evaluation is now considered an indicator of LC activity. Since mastication activates trigeminal afferent neurons, the aims of the present study, conducted on healthy adult participants, were to investigate whether chewing a bolus of different hardness may: (1) differentially affect the performance on a cognitive task (consisting in the retrieval of specific target numbers within numerical matrices) and (2) increase the dilatation of the pupil (mydriasis) induced by a haptic task, suggesting a change in LC activation. Results show that chewing significantly increased both the velocity of number retrieval (without affecting the number of errors) and the mydriasis associated with the haptic task, whereas simple task repetition did not modify either retrieval or mydriasis. Handgrip exercise, instead, significantly decreased both parameters. Effects were significantly stronger and longer lasting when subjects chewed hard pellets. Finally, chewing-induced improvements in performance and changes in mydriasis were positively correlated, which suggests that trigeminal signals enhanced by chewing may boost the cognitive performance by increasing LC activity. PMID:28848404

Functional Coherence in the State Education Agency: A Structure for Performance Management. Solutions. Issue No. 4

ERIC Educational Resources Information Center

Redding, Sam; Nafziger, Dean

2013-01-01

The purpose of the state education agency (SEA) is to focus the entire education system on helping students become capable in college and career in an increasingly complex world. One of the most vexing problems facing SEAs today is how to meet increasing demands for performance while adjusting to significant resource reductions. Meeting that…

Whole body heat stress increases motor cortical excitability and skill acquisition in humans

PubMed Central

Littmann, Andrew E.; Shields, Richard K.

2015-01-01

Objective Vigorous systemic exercise stimulates a cascade of molecular and cellular processes that enhance central nervous system (CNS) plasticity and performance. The influence of heat stress on CNS performance and learning is novel. We designed two experiments to determine whether passive heat stress 1) facilitated motor cortex excitability and 2) improved motor task acquisition compared to no heat stress. Methods Motor evoked potentials (MEPs) from the first dorsal interosseus (FDI) were collected before and after 30 minutes of heat stress at 73° C. A second cohort of subjects performed a motor learning task using the FDI either following heat or the no heat condition. Results Heat stress increased heart rate to 65% of age-predicted maximum. After heat, mean resting MEP amplitude increased 48% (P < 0.05). MEP stimulus-response amplitudes did not differ according to stimulus intensity. In the second experiment, heat stress caused a significant decrease in absolute and variable error (p < 0.05) during a novel movement task using the FDI. Conclusions Passive environmental heat stress 1) increases motor cortical excitability, and 2) enhances performance in a motor skill acquisition task. Significance Controlled heat stress may prime the CNS to enhance motor skill acquisition during rehabilitation. PMID:26616546

The immediate effects of deep breathing exercises on atelectasis and oxygenation after cardiac surgery.

PubMed

Westerdahl, Elisabeth; Lindmark, Birgitta; Eriksson, Tomas; Hedenstierna, Göran; Tenling, Arne

2003-12-01

Objective--To investigate the effects of deep breathing performed on the second postoperative day after coronary artery bypass graft surgery. Design--The immediate effects of 30 deep breaths performed without a mechanical device (n = 21), with a blow bottle device (n = 20) and with an inspiratory resistance-positive expiratory pressure mask (n = 20) were studied. Spiral computed tomography and arterial blood gas analyses were performed immediately before and after the intervention. Results--Deep breathing caused a significant decrease in atelectatic area from 12.3 +/- 7.3% to 10.2 +/- 6.7% (p < 0.0001) of total lung area 1 cm above the diaphragm and from 3.9 +/- 3.5% to 3.3 +/- 3.1% (p < 0.05) 5 cm above the diaphragm. No difference between the breathing techniques was found. The aerated lung area increased by 5% (p < 0.001). The PaO (2) increased by 0.2 kPa (p < 0.05), while PaCO (2) was unchanged in the three groups. Conclusion--A significant decrease of atelectatic area, increase in aerated lung area and a small increase in PaO (2) were found after performance of 30 deep breaths. No difference between the three breathing techniques was found.

Effects of Dehydration on Cricket Specific Skill Performance in Hot and Humid Conditions.

PubMed

Gamage, Janaka P; De Silva, Angela P; Nalliah, Arjan K; Galloway, Stuart D R

2016-12-01

The aim of the current study was to assess the effects of dehydration on cricket specific motor skill performance among fast-bowlers, fielders, and batsmen playing in a hot and humid environment. 10 fast-bowlers, 12 fielders and 8 batsmen participated in two field trials conducted 7 days apart: a fluid provision trial (FP) and a fluid restriction trial (FR). Each trial consisted of a 2-hr standardized training session and pretraining and posttraining skill performance assessments. Bowling speed and accuracy (line and length), throwing speed and accuracy (overarm, sidearm and underarm) and timed running between wickets (1, 2, and 3 runs) was assessed pre to posttraining in each trial. Mass loss was 0.6 ± 0.3 kg (0.9 ± 0.5%) in FP, and 2.6 ± 0.5kg (3.7 ± 0.8%) in FR trials. Maintaining mass within 1% of initial values did not cause any significant skill performance decline. However, the dehydration on the FR trial induced a significant time and trial effect for bowling speed by 1.0 ± 0.8% reduction (0.3 ± 0.8% reduction in FP trial; p < .01) and 19.8 ± 17.3% reduction in bowling accuracy for line (3.6 ± 14.2% reduction in FP trial; p < .01), but no effect on bowling length. A significant decline was noted in the FR trial for throwing speed for overarm (6.6 ± 4.1%; p < .01; 1.6 ± 3.4% reduction in FP trial) and sidearm (4.1 ± 2.3%; p < .01; 0.6 ± 4.7% increase in FP trial) techniques, and for throwing accuracy for overarm (14.2 ± 16.3%; p < .01; 0.8 ± 24.2% increase in FP trial) and sidearm (22.3 ± 13.3%; p < .05; 3.2 ± 34.9% reduction in FP trial) techniques. Batsmen demonstrated significant performance drop in making three runs (0.8 ± 1.2% increase in time in FP trial and 2.2 ± 1.7% increase in time in FR trial; p < .01). Moderate-severe dehydration of 3.7% body mass loss significantly impairs motor skill performance among cricketers, particularly bowlers and fielders, playing in hot and humid conditions. Fluid ingestion strategies maintaining mass loss within 1% prevented a decline in skill performance.

Effects of dietary marigold extract supplementation on growth performance, pigmentation, antioxidant capacity and meat quality in broiler chickens.

PubMed

Wang, Shuhao; Zhang, Lin; Li, Jiaolong; Cong, Jiahui; Gao, Feng; Zhou, Guanghong

2017-01-01

This experiment was conducted to investigate the effects of dietary supplementation with marigold extract on growth performance, pigmentation, antioxidant capacity and meat quality in broiler chickens. A total of 320 one-day-old Arbor Acres chickens were randomly divided into 5 groups with 8 replicates of 8 chickens each. The chickens of control group were fed with basal diet and other experimental groups were fed with basal diet supplemented with 0.075%, 0.15%, 0.30%, and 0.60% marigold extract respectively (the corresponding concentrations of lutein were 15, 30, 60, and 120 mg/kg). The results showed that marigold extract supplementation increased the yellowness values of shank, beak, skin and muscle and the redness (a*) value of thigh muscle (linear, p<0.01). Marigold extract supplementation significantly increased the total antioxidant capacity, and the activities of superoxide dismutase in liver and thigh muscle (linear, p<0.01) and significantly decreased the malondialdehyde contents of liver and thigh muscle (linear, p<0.01). Marigold extract supplementation significantly decreased the drip loss and shear force of thigh muscles (linear, p<0.01). There was no significant effect on growth performance with marigold extract supplementation. In conclusion, dietary supplementation of marigold extract significantly increased the yellowness values of carcass, antioxidant capacity and meat quality in broiler chickens.

Effects of dietary marigold extract supplementation on growth performance, pigmentation, antioxidant capacity and meat quality in broiler chickens

PubMed Central

Wang, Shuhao; Zhang, Lin; Li, Jiaolong; Cong, Jiahui; Gao, Feng; Zhou, Guanghong

2017-01-01

Objective This experiment was conducted to investigate the effects of dietary supplementation with marigold extract on growth performance, pigmentation, antioxidant capacity and meat quality in broiler chickens. Methods A total of 320 one-day-old Arbor Acres chickens were randomly divided into 5 groups with 8 replicates of 8 chickens each. The chickens of control group were fed with basal diet and other experimental groups were fed with basal diet supplemented with 0.075%, 0.15%, 0.30%, and 0.60% marigold extract respectively (the corresponding concentrations of lutein were 15, 30, 60, and 120 mg/kg). Results The results showed that marigold extract supplementation increased the yellowness values of shank, beak, skin and muscle and the redness (a*) value of thigh muscle (linear, p<0.01). Marigold extract supplementation significantly increased the total antioxidant capacity, and the activities of superoxide dismutase in liver and thigh muscle (linear, p<0.01) and significantly decreased the malondialdehyde contents of liver and thigh muscle (linear, p<0.01). Marigold extract supplementation significantly decreased the drip loss and shear force of thigh muscles (linear, p<0.01). There was no significant effect on growth performance with marigold extract supplementation. Conclusion In conclusion, dietary supplementation of marigold extract significantly increased the yellowness values of carcass, antioxidant capacity and meat quality in broiler chickens. PMID:27282969

Physiological acclimation of the green tidal alga Ulva prolifera to a fast-changing environment.

PubMed

Wu, Hailong; Gao, Guang; Zhong, Zhihai; Li, Xinshu; Xu, Juntian

2018-06-01

To aid early warning and prevent the outbreak of green tides in the Yellow Sea, both the growth and photosynthetic performance of Ulva prolifera were studied after culture in different temperatures (18, 22, and 26 °C) and light intensities (44, 160, and 280 μmol m -2 ·s -1 ). Furthermore, their instantaneous net photosynthetic performance (INPP) was studied to determine the resulting environmental acclimation. The relative growth rates of U. prolifera significantly decreased in response to increasing temperature, while they increased with increasing light intensity. Culture at higher light intensities significantly increased INPP, while higher temperatures decreased the INPP. Culture at lower temperatures lowered INPP, while increased growth temperature increased the effect. These results suggest that high temperatures during the cold season inhibited U. prolifera growth. However, low temperatures during the warm season increase biomass and may cause a large-scale green tide. These results help to understand the correlation between U. prolifera blooms and extreme weather. Copyright © 2018 Elsevier Ltd. All rights reserved.

Lactobacillus plantarum TWK10 Supplementation Improves Exercise Performance and Increases Muscle Mass in Mice

PubMed Central

Chen, Yi-Ming; Wei, Li; Chiu, Yen-Shuo; Hsu, Yi-Ju; Tsai, Tsung-Yu; Wang, Ming-Fu; Huang, Chi-Chang

2016-01-01

Lactobacillus plantarum (L. plantarum) is a well-known probiotic among the ingested-microorganism probiotics (i.e., ingested microorganisms associated with beneficial effects for the host). However, few studies have examined the effects of L. plantarum TWK10 (LP10) supplementation on exercise performance, physical fatigue, and gut microbial profile. Male Institute of Cancer Research (ICR) strain mice were divided into three groups (n = 8 per group) for oral administration of LP10 for six weeks at 0, 2.05 × 108, or 1.03 × 109 colony-forming units/kg/day, designated the vehicle, LP10-1X and LP10-5X groups, respectively. LP10 significantly decreased final body weight and increased relative muscle weight (%). LP10 supplementation dose-dependently increased grip strength (p < 0.0001) and endurance swimming time (p < 0.001) and decreased levels of serum lactate (p < 0.0001), ammonia (p < 0.0001), creatine kinase (p = 0.0118), and glucose (p = 0.0151) after acute exercise challenge. The number of type I fibers (slow muscle) in gastrocnemius muscle significantly increased with LP10 treatment. In addition, serum levels of albumin, blood urea nitrogen, creatinine, and triacylglycerol significantly decreased with LP10 treatment. Long-term supplementation with LP10 may increase muscle mass, enhance energy harvesting, and have health-promotion, performance-improvement, and anti-fatigue effects. PMID:27070637

Effects of methionine and betaine supplementation on growth performance, carcase composition and metabolism of lipids in male broilers.

PubMed

Zhan, X A; Li, J X; Xu, Z R; Zhao, R Q

2006-10-01

1. This study was conducted to investigate the effects of methionine and betaine supplementation on growth performance, carcase composition and lipid metabolism in growing broilers. 2. A total of 450 commercial broilers, 22 d of age, were randomly allocated to three groups, each of which included three replicates (50 birds per replicate). The groups received the same methionine-deficient diet supplemented with 0 or 1 g/kg methionine, or 0.5 g/kg betaine, respectively. 3. Methionine and betaine supplementation significantly improved weight gain and feed conversion. Supplemental methionine and betaine also significantly increased breast muscle yield and decreased abdominal fat content. Meanwhile, addition of methionine and betaine significantly increased the contents of creatine and free carnitine in liver, the activity of hormone-sensitive lipase in abdominal fat and the concentration of free fatty acid in serum, whereas uric acid concentration in serum was significantly decreased. 4. The results of this study suggest that betaine can spare methionine in its function as an essential amino acid and is as effective as methionine in improving performance and carcase quality of growing broilers if the diet is moderately deficient in methionine. The decrease in abdominal fat may be due to the increased carnitine synthesis in liver and hormone-sensitive lipase activity in abdominal fat.

The effects of creatine supplementation on thermoregulation and isokinetic muscular performance following acute (3-day) supplementation.

PubMed

Rosene, J M; Matthews, T D; Mcbride, K J; Galla, A; Haun, M; Mcdonald, K; Gagne, N; Lea, J; Kasen, J; Farias, C

2015-12-01

The purpose of this investigation was to determine the effects of 3 d of creatine supplementation on thermoregulation and isokinetic muscular performance. Fourteen males performed two exercise bouts following 3 d of creatine supplementation and placebo. Subjects exercised for 60 min at 60-65% of VO2max in the heat followed by isokinetic muscular performance at 60, 180, and 300°·s(-1). Dependent variables for pre- and postexercise included nude body weight, urine specific gravity, and serum creatinine levels. Total body water, extracellular water and intracellular water were measured pre-exercise. Core temperature was assessed every 5 min during exercise. Peak torque and Fatigue Index were used to assess isokinetic muscular performance. Core temperature increased during the run for both conditions. Total body water and extracellular water were significantly greater (P<0.05) following creatine supplementation. No significant difference (P>0.05) was found between conditions for intracellular water, nude body weight, urine specific gravity, and serum creatinine. Pre-exercise scores for urine specific gravity and serum creatinine were significantly less (P<0.05) versus post-exercise. No significant differences (P>0.05) were found in peak torque values or Fatigue Index between conditions for each velocity. A significant (P<0.05) overall velocity effect was found for both flexion and extension. As velocity increased, mean peak torque values decreased. Three d of creatine supplementation does not affect thermoregulation during submaximal exercise in the heat and is not enough to elicit an ergogenic effect for isokinetic muscle performance following endurance activity.

Repeated administration of fresh garlic increases memory retention in rats.

PubMed

Haider, Saida; Naz, Nosheen; Khaliq, Saima; Perveen, Tahira; Haleem, Darakhshan J

2008-12-01

Garlic (Allium sativum) is regarded as both a food and a medicinal herb. Increasing attention has focused on the biological functions and health benefits of garlic as a potentially major dietary component. Chronic garlic administration has been shown to enhance memory function. Evidence also shows that garlic administration in rats affects brain serotonin (5-hydroxytryptamine [5-HT]) levels. 5-HT, a neurotransmitter involved in a number of physiological functions, is also known to enhance cognitive performance. The present study was designed to investigate the probable neurochemical mechanism responsible for the enhancement of memory following garlic administration. Sixteen adult locally bred male albino Wistar rats were divided into control (n = 8) and test (n = 8) groups. The test group was orally administered 250 mg/kg fresh garlic homogenate (FGH), while control animals received an equal amount of water daily for 21 days. Estimation of plasma free and total tryptophan (TRP) and whole brain TRP, 5-HT, and 5-hydroxyindole acetic acid (5-HIAA) was determined by high-performance liquid chromatography with electrochemical detection. For assessment of memory, a step-through passive avoidance paradigm (electric shock avoidance) was used. The results showed that the levels of plasma free TRP significantly increased (P < .01) and plasma total TRP significantly decreased (P < .01) in garlic-treated rats. Brain TRP, 5-HT, and 5-HIAA levels were also significantly increased following garlic administration. A significant improvement in memory function was exhibited by garlic-treated rats in the passive avoidance test. Increased brain 5-HT levels were associated with improved cognitive performance. The present results, therefore, demonstrate that the memory-enhancing effect of garlic may be associated with increased brain 5-HT metabolism in rats. The results further support the use of garlic as a food supplement for the enhancement of memory.

Evaluating the impact of the reconfiguration of gynaecology services at a University Hospital NHS trust in the United Kingdom.

PubMed

Choo, Teck; Deb, Shilpa; Wilkins, Joanne; Atiomo, William

2014-09-24

The project aim was to investigate the impact of reconfiguring gynaecology services on the key performance indicators of a University Hospital NHS Trust in the UK. The reconfiguration involved the centralisation of elective gynaecology on one hospital site and emergency gynaecology on the other. Data measuring outcomes of the Trust's performance indicators (clinical outcomes, patient experience, staff satisfaction, teaching/training, research/development and value for money) were collected. Two time periods, 12 months before and after the reconfiguration in March 2011, were compared for all outcome measures except patient experience. Retrospective data from the hospitals audit department on clinical activity/outcomes and emergency gynaecology patient's feedback questionnaires were analysed. Staff satisfaction, teaching/training and research/development were measured through an online survey of gynaecology consultants. Post reconfiguration, the total number of admissions reduced by 6% (6,867 vs 6,446). There was a 14% increase in elective theatre sessions available (902.29 vs 1030.57) and an 84% increase in elective theatre sessions cancelled (44.43 vs 81.71). However, the average number of elective operations performed during each theatre session remained similar (2.63 vs 2.5). There was a significant increase in medical devices related clinical incidents (2 vs 11). With patient experience, there was a significant reduction in patient's overall length of stay on the emergency gynaecology ward and waiting times for investigations. For staff satisfaction, Consultants were significantly more dissatisfied with workload (3.45 vs 2.85) and standards of care (3.75 vs 2.93). With research and development, consultants remained dissatisfied with time/funding/opportunities for research. No significant impact on undergraduate/postgraduate teaching was found. No financial data on gynaecology was provided for the assessment of value for money. Reconfiguration of gynaecology services at this Trust may have resulted in a reduction in gynaecological activity and increased cancellation of elective operations but did not significantly reduce the number of elective operations performed. Although consultants expressed increased dissatisfaction with standards of clinical care, clinical incident reports did not significantly increase apart from medical devices incidents. Patient experience of emergency gynaecology services was improved. This manuscript provides a framework for similar exercises evaluating the impact of service redesign in the NHS.

The High Stability Engine Control (HISTEC) Program: Flight Demonstration Phase

NASA Technical Reports Server (NTRS)

DeLaat, John C.; Southwick, Robert D.; Gallops, George W.; Orme, John S.

1998-01-01

Future aircraft turbine engines, both commercial and military, must be able to accommodate expected increased levels of steady-state and dynamic engine-face distortion. The current approach of incorporating sufficient design stall margin to tolerate these increased levels of distortion would significantly reduce performance. The objective of the High Stability Engine Control (HISTEC) program is to design, develop, and flight-demonstrate an advanced, integrated engine control system that uses measurement-based estimates of distortion to enhance engine stability. The resulting distortion tolerant control reduces the required design stall margin, with a corresponding increase in performance and decrease in fuel burn. The HISTEC concept has been developed and was successfully flight demonstrated on the F-15 ACTIVE aircraft during the summer of 1997. The flight demonstration was planned and carried out in two phases, the first to show distortion estimation, and the second to show distortion accommodation. Post-flight analysis shows that the HISTEC technologies are able to successfully estimate and accommodate distortion, transiently setting the stall margin requirement on-line and in real-time. This allows the design stall margin requirement to be reduced, which in turn can be traded for significantly increased performance and/or decreased weight. Flight demonstration of the HISTEC technologies has significantly reduced the risk of transitioning the technology to tactical and commercial engines.

Isoflavones, calcium, vitamin D and inulin improve quality of life, sexual function, body composition and metabolic parameters in menopausal women: result from a prospective, randomized, placebo-controlled, parallel-group study.

PubMed

Vitale, Salvatore Giovanni; Caruso, Salvatore; Rapisarda, Agnese Maria Chiara; Cianci, Stefano; Cianci, Antonio

2018-03-01

Menopause results in metabolic changes that contribute to increase risk of cardiovascular diseases: increase in low density lipoprotein (LDL) and triglycerides and decrease in high density lipoprotein (HDL), weight gain are associated with a correspondent increase in incidence of hypertension and diabetes. The aim of this study was to evaluate the effect of a preparation of isoflavones, calcium vitamin D and inulin in menopausal women. We performed a prospective, randomized, placebo-controlled, parallel-group study. A total of 50 patients were randomized to receive either oral preparations of isoflavones (40 mg), calcium (500 mg) vitamin D (300 UI) and inulin (3 g) or placebo (control group). Pre- and post-treatment assessment of quality of life and sexual function were performed through Menopause-Specific Quality of Life Questionnaire (MENQOL) and Female Sexual Function Index (FSFI); evaluations of anthropometric indicators, body composition through bioelectrical impedance analyser, lumbar spine and proximal femur T-score and lipid profile were performed. After 12 months, a significant reduction in MENQOL vasomotor, physical and sexual domain scores ( p < 0.05) and a significant increase in all FSFI domain scores ( p < 0.05) were observed in treatment group. Laboratory tests showed significant increase in serum levels of HDL ( p < 0.05). No significant changes of lumbar spine and femur neck T-score ( p > 0.05) were found in the same group. According to our data analysis, isoflavones, calcium, vitamin D and inulin may exert favourable effects on menopausal symptoms and signs.

Effect of Stimulation Rate on Cochlear Implant Users’ Phoneme, Word and Sentence Recognition in Quiet and in Noise

PubMed Central

Shannon, Robert V.; Cruz, Rachel J.; Galvin, John J.

2011-01-01

High stimulation rates in cochlear implants (CI) offer better temporal sampling, can induce stochastic-like firing of auditory neurons and can increase the electric dynamic range, all of which could improve CI speech performance. While commercial CI have employed increasingly high stimulation rates, no clear or consistent advantage has been shown for high rates. In this study, speech recognition was acutely measured with experimental processors in 7 CI subjects (Clarion CII users). The stimulation rate varied between (approx.) 600 and 4800 pulses per second per electrode (ppse) and the number of active electrodes varied between 4 and 16. Vowel, consonant, consonant-nucleus-consonant word and IEEE sentence recognition was acutely measured in quiet and in steady noise (+10 dB signal-to-noise ratio). Subjective quality ratings were obtained for each of the experimental processors in quiet and in noise. Except for a small difference for vowel recognition in quiet, there were no significant differences in performance among the experimental stimulation rates for any of the speech measures. There was also a small but significant increase in subjective quality rating as stimulation rates increased from 1200 to 2400 ppse in noise. Consistent with previous studies, performance significantly improved as the number of electrodes was increased from 4 to 8, but no significant difference showed between 8, 12 and 16 electrodes. Altogether, there was little-to-no advantage of high stimulation rates in quiet or in noise, at least for the present speech tests and conditions. PMID:20639631

Effect of a Physical Examination Teaching Program on the Behavior of Medical Residents

PubMed Central

McMahon, Graham T; Marina, Ovidiu; Kritek, Patricia A; Katz, Joel T

2005-01-01

Context The reliance on physical examination as a diagnostic aid is in decline. Objective To determine whether an educational program can increase the use of physical examination by medical residents. Design and Participants A series of educational workshops were provided to 47 second- and third-year medical residents at a large academic teaching hospital. Measurements Interns and students reported the frequency and depth of clinical examination performance on morning rounds by their residents before and up to six months after the workshops. Behavior before and after the workshops was compared using a mixed model. Results A total of 374 reports were returned (77% response). After adjusting for the type of service and observer, there was a statistically significant 23% increase (P=.02) in the performance of physical examination among residents who attended the course. Residents significantly increased the fraction of patients they examined on rounds (absolute increase 11%, P=.002) but did not increase the depth of their examination. The change was greatest on general medical teams, among whom the performance of physical examination had been least frequent. Teaching and feedback events on medicine teams by residents to their interns (2.8 and 1.1 events per 2 weeks, respectively) and medical students (5.9 and 2.8 events per 2 weeks, respectively) remained infrequent. Conclusions A skills improvement program can significantly increase the frequency of physical examination, but teaching and feedback events remain sporadic and infrequent. PMID:16050879

Augmentation of aerobic respiration and mitochondrial biogenesis in skeletal muscle by hypoxia preconditioning with cobalt chloride

DOE Office of Scientific and Technical Information (OSTI.GOV)

Saxena, Saurabh; Shukla, Dhananjay; Bansal, Anju, E-mail: anjubansaldipas@gmail.com

High altitude/hypoxia training is known to improve physical performance in athletes. Hypoxia induces hypoxia inducible factor-1 (HIF-1) and its downstream genes that facilitate hypoxia adaptation in muscle to increase physical performance. Cobalt chloride (CoCl{sub 2}), a hypoxia mimetic, stabilizes HIF-1, which otherwise is degraded in normoxic conditions. We studied the effects of hypoxia preconditioning by CoCl{sub 2} supplementation on physical performance, glucose metabolism, and mitochondrial biogenesis using rodent model. The results showed significant increase in physical performance in cobalt supplemented rats without (two times) or with training (3.3 times) as compared to control animals. CoCl{sub 2} supplementation in rats augmentedmore » the biological activities of enzymes of TCA cycle, glycolysis and cytochrome c oxidase (COX); and increased the expression of glucose transporter-1 (Glut-1) in muscle showing increased glucose metabolism by aerobic respiration. There was also an increase in mitochondrial biogenesis in skeletal muscle observed by increased mRNA expressions of mitochondrial biogenesis markers which was further confirmed by electron microscopy. Moreover, nitric oxide production increased in skeletal muscle in cobalt supplemented rats, which seems to be the major reason for peroxisome proliferator activated receptor-gamma coactivator-1α (PGC-1α) induction and mitochondrial biogenesis. Thus, in conclusion, we state that hypoxia preconditioning by CoCl{sub 2} supplementation in rats increases mitochondrial biogenesis, glucose uptake and metabolism by aerobic respiration in skeletal muscle, which leads to increased physical performance. The significance of this study lies in understanding the molecular mechanism of hypoxia adaptation and improvement of work performance in normal as well as extreme conditions like hypoxia via hypoxia preconditioning. -- Highlights: ► We supplemented rats with CoCl{sub 2} for 15 days along with training. ► CoCl{sub 2} supplementation augmented endurance performance and aerobic respiration. ► It increased glucose uptake and metabolism in muscle. ► It enhanced mitochondrial biogenesis in red gastrocnemius muscle.« less

The effect of a competitive wrestling season on body weight, hydration, and muscular performance in collegiate wrestlers.

PubMed

Buford, Thomas W; Rossi, Stephen J; Smith, Douglas B; O'Brien, Matthew S; Pickering, Chris

2006-08-01

The purpose of the present investigation was to examine the effects of a collegiate wrestling season on body weight, hydration, and muscular performance. Twelve Division I collegiate wrestlers (mean +/- SE; 20.75 +/- 0.41 year) volunteered to participate in testing sessions during midseason and 3 weeks following the season. Testing consisted of weigh-in, providing a urine sample for hydration analysis, and a measure of isometric leg extension peak torque. Weight significantly increased (p < 0.05) following the completion of the competitive season. No significant change in urine specific gravity (p > 0.05) was observed. Muscular performance was affected by the season as peak torque (PT) and PT-to-body weight ratio increased significantly (p < 0.05). Following the collegiate wrestling season, augmentation in body weight and muscular performance of the wrestlers occurs without alterations in hydration status. Further research is warranted on what type of strength training program would most effectively reduce the decrements in strength associated with weight loss and the strain of a competitive season.

Maximal strength and cortisol responses to psyching-up during the squat exercise.

PubMed

McGuigan, Michael R; Ghiagiarelli, Jamie; Tod, David

2005-07-01

We studied the effect of psyching-up on one-repetition maximum (1-RM) performance and salivary cortisol responses during the squat exercise. Ten men (age 21.6+/-1.4 years; mean+/-s) and ten women (age 22.4+/-2.8 years) with weight training experience of 4.5+/-2.0 years participated in this study. One-repetition maximum squats were performed on a Smith machine during each of two different intervention conditions that were counterbalanced and consisted of a free choice psych-up and a cognitive distraction. Saliva samples were obtained at the beginning of each test session and immediately after the final 1-RM attempt. No significant difference in 1-RM was identified between psyching-up (104+/-50 kg) and cognitive distraction (106+/-52 kg). Performing a 1-RM in the squat exercise significantly increased salivary cortisol concentrations during both conditions (P<0.05). There was no significant difference in salivary cortisol responses between conditions. These results suggest that psyching-up does not increase 1-RM performance during the squat exercise in strength-trained individuals.

The effects of wearing undersized lower-body compression garments on endurance running performance.

PubMed

Dascombe, Ben J; Hoare, Trent K; Sear, Joshua A; Reaburn, Peter R; Scanlan, Aaron T

2011-06-01

To examine whether wearing various size lower-body compression garments improves physiological and performance parameters related to endurance running in well-trained athletes. Eleven well-trained middle-distance runners and triathletes (age: 28.4 ± 10.0 y; height: 177.3 ± 4.7 cm; body mass: 72.6 ± 8.0 kg; VO2max: 59.0 ± 6.7 mL·kg-1·min-1) completed repeat progressive maximal tests (PMT) and time-to-exhaustion (TTE) tests at 90% VO2max wearing either manufacturer-recommended LBCG (rLBCG), undersized LBCG (uLBCG), or loose running shorts (CONT). During all exercise testing, several systemic and peripheral physiological measures were taken. The results indicated similar effects of wearing rLBCG and uLBCG compared with the control. Across the PMT, wearing either LBCG resulted in significantly (P < .05) increased oxygen consumption, O2 pulse, and deoxyhemoglobin (HHb) and decreased running economy, oxyhemoglobin, and tissue oxygenation index (TOI) at low-intensity speeds (8-10 km·h-1). At higher speeds (12-18 km·h-1), wearing LBCG increased regional blood flow (nTHI) and HHb values, but significantly lowered heart rate and TOI. During the TTE, wearing either LBCG significantly (P < .05) increased HHb concentration, whereas wearing uLBCG also significantly (P < .05) increased nTHI. No improvement in endurance running performance was observed in either compression condition. The results suggest that wearing LBCG facilitated a small number of cardiorespiratory and peripheral physiological benefits that appeared mostly related to improvements in venous flow. However, these improvements appear trivial to athletes, as they did not correspond to any improvement in endurance running performance.

The effectiveness of a cognitive task analysis informed curriculum to increase self-efficacy and improve performance for an open cricothyrotomy.

PubMed

Campbell, Julia; Tirapelle, Leslie; Yates, Kenneth; Clark, Richard; Inaba, Kenji; Green, Donald; Plurad, David; Lam, Lydia; Tang, Andrew; Cestero, Ramon; Sullivan, Maura

2011-01-01

This study explored the effects of a cognitive task analysis (CTA)-informed curriculum to increase surgical skills performance and self-efficacy beliefs for medical students and postgraduate surgical residents learning how to perform an open cricothyrotomy. Third-year medical students and postgraduate year 2 and 3 surgery residents were assigned randomly to either the CTA group (n = 12) or the control group (n = 14). The CTA group learned the open cricothyrotomy procedure using the CTA curriculum. The control group received the traditional curriculum. The CTA group outperformed the control group significantly based on a 19-point checklist score (CTA mean score: 17.75, standard deviation [SD] = 2.34; control mean score: 15.14, SD = 2.48; p = 0.006). The CTA group also reported significantly higher self-efficacy scores based on a 140-point self-appraisal inventory (CTA mean score: 126.10, SD = 16.90; control: 110.67, SD = 16.8; p = 0.029). The CTA curriculum was effective in increasing the performance and self-efficacy scores for postgraduate surgical residents and medical students performing an open cricothyrotomy. Copyright © 2011 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

The effects of whole-body vibration exercise on isokinetic muscular function of the knee and jump performance depending on squatting position

PubMed Central

Kim, Jaeyuong; Park, Yunjin; Seo, Yonggon; Kang, Gyumin; Park, Sangseo; Cho, Hyeyoung; Moon, Hyunghoon; Kim, Myungki; Yu, Jaeho

2016-01-01

[Purpose] The purpose of this study was to investigate the effects of whole-body vibration exercise (WBVE) on isokinetic muscular function of the knee and jump performance depending on different squatting positions. [Subjects] The subjects were 12 healthy adult men who did not exercise regularly between the ages of 27 and 34. [Methods] WBVE was performed with high squat position (SP), middle SP, and low SP. Before and after the intervention, isokinetic muscular function of the knees and jump performance were measured. [Results] Knee flexion peak torque at 60°/s and total work at 180°/s were significantly increased after implementing WBVE. Jump height also significantly increased after completing the exercise at all positions in comparison with the pre-exercise programs. [Conclusion] The results of this study suggest that SP during WBVE is an important factor stimulating positive effects on muscular function. PMID:26957749

Process-oriented guided inquiry learning strategy enhances students' higher level thinking skills in a pharmaceutical sciences course.

PubMed

Soltis, Robert; Verlinden, Nathan; Kruger, Nicholas; Carroll, Ailey; Trumbo, Tiffany

2015-02-17

To determine if the process-oriented guided inquiry learning (POGIL) teaching strategy improves student performance and engages higher-level thinking skills of first-year pharmacy students in an Introduction to Pharmaceutical Sciences course. Overall examination scores and scores on questions categorized as requiring either higher-level or lower-level thinking skills were compared in the same course taught over 3 years using traditional lecture methods vs the POGIL strategy. Student perceptions of the latter teaching strategy were also evaluated. Overall mean examination scores increased significantly when POGIL was implemented. Performance on questions requiring higher-level thinking skills was significantly higher, whereas performance on questions requiring lower-level thinking skills was unchanged when the POGIL strategy was used. Student feedback on use of this teaching strategy was positive. The use of the POGIL strategy increased student overall performance on examinations, improved higher-level thinking skills, and provided an interactive class setting.

Effects of noise on the performance of a memory decision response task

NASA Technical Reports Server (NTRS)

Lawton, B. W.

1972-01-01

An investigation has been made to determine the effects of noise on human performance. Fourteen subjects performed a memory-decision-response task in relative quiet and while listening to tape recorded noises. Analysis of the data obtained indicates that performance was degraded in the presence of noise. Significant increases in problem solution times were found for impulsive noise conditions as compared with times found for the no-noise condition. Performance accuracy was also degraded. Significantly more error responses occurred at higher noise levels; a direct or positive relation was found between error responses and noise level experienced by the subjects.

Cardiorespiratory performance and physical activity in normal weight and overweight Finnish adolescents from 2003 to 2010.

PubMed

Palomäki, Sanna; Heikinaro-Johansson, Pilvikki; Huotari, Pertti

2015-01-01

We investigated changes in cardiorespiratory performance, BMI and leisure-time physical activity among Finnish adolescents from 2003 to 2010. In addition, we compared cardiorespiratory performance levels between normal weight and overweight adolescents, grouped according to their physical activity. Participants were a national representative samples of 15-16-year-old adolescents in their final (ninth) year of comprehensive school in 2003 (n = 2258) and in 2010 (n = 1301). They performed an endurance shuttle run test and reported their height and weight and leisure time physical activity on a questionnaire. Results showed no significant secular changes in cardiorespiratory performance from 2003 to 2010. The mean BMI increased in boys. Leisure-time physical activity increased among normal weight girls. Adolescents of normal weight had better cardiorespiratory performance than those classified as overweight at both assessment points. BMI-adjusted physical activity was a significant determinant for cardiorespiratory performance among overweight adolescents, and very active overweight adolescents had similar cardiorespiratory performance levels as moderately active adolescents of normal weight. The results of the present study support the idea that the physical activity has the great importance for the cardiorespiratory performance in adolescents. Overweight adolescents, in particular, benefit from higher levels of physical activity.

Trend analysis of body weight parameters, mortality, and incidence of spontaneous tumors in Tg.rasH2 mice.

PubMed

Paranjpe, Madhav G; Denton, Melissa D; Vidmar, Tom; Elbekai, Reem H

2014-01-01

Carcinogenicity studies have been performed in conventional 2-year rodent studies for at least 3 decades, whereas the short-term carcinogenicity studies in transgenic mice, such as Tg.rasH2, have only been performed over the last decade. In the 2-year conventional rodent studies, interlinked problems, such as increasing trends in the initial body weights, increased body weight gains, high incidence of spontaneous tumors, and low survival, that complicate the interpretation of findings have been well established. However, these end points have not been evaluated in the short-term carcinogenicity studies involving the Tg.rasH2 mice. In this article, we present retrospective analysis of data obtained from control groups in 26-week carcinogenicity studies conducted in Tg.rasH2 mice since 2004. Our analysis showed statistically significant decreasing trends in initial body weights of both sexes. Although the terminal body weights did not show any significant trends, there was a statistically significant increasing trend toward body weight gains, more so in males than in females, which correlated with increasing trends in the food consumption. There were no statistically significant alterations in mortality trends. In addition, the incidence of all common spontaneous tumors remained fairly constant with no statistically significant differences in trends. © The Author(s) 2014.

An Evaluation on the Ratio of Plant to Animal Protein in the Diet of Juvenile Sea Cucumber (Apostichopus japonicus): Growth, Nutrient Digestibility and Nonspecific Immunity

NASA Astrophysics Data System (ADS)

Bao, Pengyun; Li, Xiaoyu; Xu, Yongping

2018-05-01

This study was conducted to evaluate the effects of plant/animal (P/A) protein ratios (viz.1:4, 1:3, 1:2, 1:1,2:1, 3:1, 4:1) on growth performance, body composition, apparent digestibility of diets, and nonspecific immunity of juvenile sea cucumber (Apostichopus japonicus). Sea cucumbers were divided into 21 plastic tanks, and each tank was stocked with 15 individuals (initial weight: about 23.73 g). Each feed was allocated to three replicates of sea cucumbers. The feeding experiment lasted for 50 days. Results indicated that weight gain rate (WGR) and body wall weight (BWW) significantly increased as dietary ratio of P/A increased from 1:4 to 3:1, and then decreased significantly with further increase of this ratio (P < 0.05). The body wall coefficient (BWC) showed a similar tendency to WGR and BWW, but no significance was detected among dietary treatments (P > 0.05). The apparent digestibility of dry matter, protein and lipid increased with ratio of P/A increasing from 1:4 to 2:1 (P < 0.05), and then decreased with further increase of this ratio. Correspondingly, activities of trypsin and amylase were significantly increased as P/A increased from 1:4 to 2:1 (P < 0.05). The activities of SOD and CAT showed a similar trend with WGR, with the highest value observed in the ratio of 1:2 and 1:1, respectively. Results above showed that moderate or relatively higher ratio of P/A protein (1:1-3:1) significantly increased the growth performance, apparent digestibility, and nonspecific immunity of sea cucumber. This will contribute to improving the feed formulation for juvenile cucumbers.

Yoga Enhances Positive Psychological States In Young Adult Musicians

PubMed Central

Butzer, Bethany; Ahmed, Khalique; Khalsa, Sat Bir S.

2016-01-01

Although yoga has been shown to be a viable technique for improving the performance of the mind and body, little attention has been directed to studying the relationship between yoga and the psychological states of flow and mindfulness. Musicians enrolled in a 2-month fellowship program in 2005, 2006 and 2007 were invited to participate in a yoga and meditation program. Fellows not participating in the yoga program were recruited separately as controls. All participants completed baseline and end-program questionnaires evaluating dispositional flow, mindfulness, confusion, and music performance anxiety. Compared to controls, yoga participants reported significant decreases in confusion and increases in dispositional flow. Yoga participants in the 2006 sample also reported significant increases in the mindfulness subscale of awareness. Correlational analyses revealed that increases in participants' dispositional flow and mindfulness scores were associated with decreases in confusion and music performance anxiety. This study demonstrates the commonalities between positive psychology and yoga, both of which are focused on enhancing human performance and promoting beneficial psychological states. The results suggest that yoga and meditation may enhance the states of flow and mindful awareness, and reduce confusion. PMID:26721471

Yoga Enhances Positive Psychological States in Young Adult Musicians.

PubMed

Butzer, Bethany; Ahmed, Khalique; Khalsa, Sat Bir S

2016-06-01

Although yoga has been shown to be a viable technique for improving the performance of the mind and body, little attention has been directed to studying the relationship between yoga and the psychological states of flow and mindfulness. Musicians enrolled in a 2-month fellowship program in 2005, 2006 and 2007 were invited to participate in a yoga and meditation program. Fellows not participating in the yoga program were recruited separately as controls. All participants completed baseline and end-program questionnaires evaluating dispositional flow, mindfulness, confusion, and music performance anxiety. Compared to controls, yoga participants reported significant decreases in confusion and increases in dispositional flow. Yoga participants in the 2006 sample also reported significant increases in the mindfulness subscale of awareness. Correlational analyses revealed that increases in participants' dispositional flow and mindfulness were associated with decreases in confusion and music performance anxiety. This study demonstrates the commonalities between positive psychology and yoga, both of which are focused on enhancing human performance and promoting beneficial psychological states. The results suggest that yoga and meditation may enhance the states of flow and mindful awareness, and reduce confusion.

Simulation-Based Mastery Learning with Deliberate Practice Improves Clinical Performance in Spinal Anesthesia

PubMed Central

Udani, Ankeet D.; Macario, Alex; Tanaka, Maria A.; Tanaka, Pedro P.

2014-01-01

Introduction. Properly performing a subarachnoid block (SAB) is a competency expected of anesthesiology residents. We aimed to determine if adding simulation-based deliberate practice to a base curriculum improved performance of a SAB. Methods. 21 anesthesia residents were enrolled. After baseline assessment of SAB on a task-trainer, all residents participated in a base curriculum. Residents were then randomized so that half received additional deliberate practice including repetition and expert-guided, real-time feedback. All residents were then retested for technique. SABs on all residents' next three patients were evaluated in the operating room (OR). Results. Before completing the base curriculum, the control group completed 81% of a 16-item performance checklist on the task-trainer and this increased to 91% after finishing the base curriculum (P < 0.02). The intervention group also increased the percentage of checklist tasks properly completed from 73% to 98%, which was a greater increase than observed in the control group (P < 0.03). The OR time required to perform SAB was not different between groups. Conclusions. The base curriculum significantly improved resident SAB performance. Deliberate practice training added a significant, independent, incremental benefit. The clinical impact of the deliberate practice intervention in the OR on patient care is unclear. PMID:25157263

Simulation-based mastery learning with deliberate practice improves clinical performance in spinal anesthesia.

PubMed

Udani, Ankeet D; Macario, Alex; Nandagopal, Kiruthiga; Tanaka, Maria A; Tanaka, Pedro P

2014-01-01

Introduction. Properly performing a subarachnoid block (SAB) is a competency expected of anesthesiology residents. We aimed to determine if adding simulation-based deliberate practice to a base curriculum improved performance of a SAB. Methods. 21 anesthesia residents were enrolled. After baseline assessment of SAB on a task-trainer, all residents participated in a base curriculum. Residents were then randomized so that half received additional deliberate practice including repetition and expert-guided, real-time feedback. All residents were then retested for technique. SABs on all residents' next three patients were evaluated in the operating room (OR). Results. Before completing the base curriculum, the control group completed 81% of a 16-item performance checklist on the task-trainer and this increased to 91% after finishing the base curriculum (P < 0.02). The intervention group also increased the percentage of checklist tasks properly completed from 73% to 98%, which was a greater increase than observed in the control group (P < 0.03). The OR time required to perform SAB was not different between groups. Conclusions. The base curriculum significantly improved resident SAB performance. Deliberate practice training added a significant, independent, incremental benefit. The clinical impact of the deliberate practice intervention in the OR on patient care is unclear.

Effects of balance training by knee joint motions on muscle activity in adult men with functional ankle instability.

PubMed

Nam, Seung-Min; Kim, Won-Bok; Yun, Chang-Kyo

2016-05-01

[Purpose] This study examined the effects of balance training by applying knee joint movements on muscle activity in male adults with functional ankle instability. [Subjects and Methods] 28 adults with functional ankle instability, divided randomly into an experimental group, which performed balance training by applying knee joint movements for 20 minutes and ankle joint exercises for 10 minutes, and a control group, which performed ankle joint exercise for 30 minutes. Exercises were completed three times a week for 8 weeks. Electromyographic values of the tibialis anterior, peroneus longus, peroneus brevis, and the lateral gastrocnemius muscles were obtained to compare and analyze muscle activity before and after the experiments in each group. [Results] The experimental group had significant increases in muscle activity in the tibialis anterior, peroneus longus, and lateral gastrocnemius muscles, while muscle activity in the peroneus brevis increased without significance. The control group had significant increases in muscle activity in the tibialis anterior and peroneus longus, while muscle activity in the peroneus brevis and lateral gastrocnemius muscles increased without significance. [Conclusion] In conclusion, balance training by applying knee joint movements can be recommended as a treatment method for patients with functional ankle instability.

The influence of anaesthetists' experience on workload, performance and visual attention during simulated critical incidents.

PubMed

Schulz, Christian M; Schneider, Erich; Kohlbecher, Stefan; Hapfelmeier, Alexander; Heuser, Fabian; Wagner, Klaus J; Kochs, Eberhard F; Schneider, Gerhard

2014-10-01

Development of accurate Situation Awareness (SA) depends on experience and may be impaired during excessive workload. In order to gain adequate SA for decision making and performance, anaesthetists need to distribute visual attention effectively. Therefore, we hypothesized that in more experienced anaesthetists performance is better and increase of physiological workload is less during critical incidents. Additionally, we investigated the relation between physiological workload indicators and distribution of visual attention. In fifteen anaesthetists, the increase of pupil size and heart rate was assessed in course of a simulated critical incident. Simulator log files were used for performance assessment. An eye-tracking device (EyeSeeCam) provided data about the anaesthetists' distribution of visual attention. Performance was assessed as time until definitive treatment. T tests and multivariate generalized linear models (MANOVA) were used for retrospective statistical analysis. Mean pupil diameter increase was 8.1% (SD ± 4.3) in the less experienced and 15.8% (±10.4) in the more experienced subjects (p = 0.191). Mean heart rate increase was 10.2% (±6.7) and 10.5% (±8.3, p = 0.956), respectively. Performance did not depend on experience. Pupil diameter and heart rate increases were associated with a shift of visual attention from monitoring towards manual tasks (not significant). For the first time, the following four variables were assessed simultaneously: physiological workload indicators, performance, experience, and distribution of visual attention between "monitoring" and "manual" tasks. However, we were unable to detect significant interactions between these variables. This experimental model could prove valuable in the investigation of gaining and maintaining SA in the operation theatre.

Unmanned Aircraft System (UAS) Delegation of Separation in NextGen Airspace

NASA Technical Reports Server (NTRS)

Kenny, Caitlin A.; Shively, Robert J.; Jordan, Kevin

2014-01-01

The purpose of this study was to determine the feasibility of unmanned aircraft systems (UAS) performing delegated separation in the national airspace system (NAS). Delegated separation is the transfer of responsibility for maintaining separation between aircraft or vehicles from air navigation service providers to the relevant pilot or flight operator. The effects of delegated separation and traffic display information level were collected through performance, workload, and situation awareness measures. The results of this study show benefits related to the use of conflict detection alerts being shown on the UAS operator's cockpit situation display (CSD), and to the use of full delegation. Overall, changing the level of separation responsibility and adding conflict detection alerts on the CSD was not found to have an adverse effect on performance as shown by the low amounts of losses of separation. The use of conflict detection alerts on the CSD and full delegation responsibilities given to the UAS operator were found to create significantly reduced workload, significantly increased situation awareness and significantly easier communications between the UAS operator and air traffic controller without significantly increasing the amount of losses of separation.

Unmanned aircraft system (UAS) delegation of separation in NextGen airspace

NASA Astrophysics Data System (ADS)

Kenny, Caitlin A.

The purpose of this thesis was to determine the feasibility of unmanned aircraft systems (UAS) performing delegated separation in the national airspace system (NAS). Delegated separation is the transfer of responsibility for maintaining separation between aircraft or vehicles from air navigation service providers to the relevant pilot or flight operator. The effects of delegated separation and traffic display information level were collected through performance, workload, and situation awareness measures. The results of this study showed benefits related to the use of conflict detection alerts being shown on the UAS operator's cockpit situation display (CSD) and to the use of full delegation. Overall, changing the level of separation responsibility and adding conflict detection alerts on the CSD were not found to have an adverse effect on performance as shown by the low amounts of losses of separation. The use of conflict detection alerts on the CSD and full delegation responsibilities given to the UAS operator were found to create significantly reduced workload, significantly increased situation awareness and significantly easier communications between the UAS operator and air traffic controller without significantly increasing the amount of losses of separation.

Does emotional intelligence change during medical school gross anatomy course? Correlations with students' performance and team cohesion.

PubMed

Holman, Michelle A; Porter, Samuel G; Pawlina, Wojciech; Juskewitch, Justin E; Lachman, Nirusha

2016-01-01

Emotional intelligence (EI) has been associated with increased academic achievement, but its impact on medical education is relatively unexplored. This study sought to evaluate change in EI, performance outcomes, and team cohesion within a team-based medical school anatomy course. Forty-two medical students completed a pre-course and post-course Schutte Self-Report Emotional Intelligence Test (SSEIT). Individual EI scores were then compared with composite course performance grade and team cohesion survey results. Mean pre-course EI score was 140.3 out of a possible 160. During the course, mean individual EI scores did not change significantly (P = 0.17) and no correlation between EI scores and academic performance was noted (P = 0.31). In addition, EI did not correlate with team cohesion (P = 0.16). While business has found significant utility for EI in increasing performance and productivity, its role in medical education is still uncertain. © 2015 American Association of Anatomists.

Green Propulsion Advancement and Infusion

NASA Technical Reports Server (NTRS)

Mulkey, Henry W.; Maynard, Andrew P.; Anflo, Kjell

2018-01-01

All space missions benefit from increased propulsion system performance, allowing lower spacecraft launch mass, larger scientific payloads, or extended on-orbit lifetimes. Likewise, long-term storable liquid propellant candidates that offer significant reduction in personnel hazards and shorter payload processing schedules present a more attractive propulsion subsystem solution to spacecraft builders. Aiming to reduce risk to potential infusion missions and fully comprehend the alternative propellant performance, the work presented herein represents many years of development and collaborative efforts to successfully align higher performance, low toxicity green propellants into NASA Goddard Space Flight Center (GSFC) missions. High Performance Green Propulsion (HPGP), and the associated propellant technology, has advanced significantly in maturity with increased familiarity with LMP-103S propellant handling, the proven reduction in loading hazards, successful launches conducted at multiple international Ranges, and HPGP on-orbit flight heritage. As science missions move forward to the potential infusion of HPGP technology, the National Aeronautics and Space Administration (NASA) and its partners are working to address gaps in system performance and operational considerations.

Quality of Education Predicts Performance on the Wide Range Achievement Test-4th Edition Word Reading Subtest

PubMed Central

Sayegh, Philip; Arentoft, Alyssa; Thaler, Nicholas S.; Dean, Andy C.; Thames, April D.

2014-01-01

The current study examined whether self-rated education quality predicts Wide Range Achievement Test-4th Edition (WRAT-4) Word Reading subtest and neurocognitive performance, and aimed to establish this subtest's construct validity as an educational quality measure. In a community-based adult sample (N = 106), we tested whether education quality both increased the prediction of Word Reading scores beyond demographic variables and predicted global neurocognitive functioning after adjusting for WRAT-4. As expected, race/ethnicity and education predicted WRAT-4 reading performance. Hierarchical regression revealed that when including education quality, the amount of WRAT-4's explained variance increased significantly, with race/ethnicity and both education quality and years as significant predictors. Finally, WRAT-4 scores, but not education quality, predicted neurocognitive performance. Results support WRAT-4 Word Reading as a valid proxy measure for education quality and a key predictor of neurocognitive performance. Future research should examine these findings in larger, more diverse samples to determine their robust nature. PMID:25404004

Ocular dimensions, corneal thickness, and corneal curvature in quarter horses with hereditary equine regional dermal asthenia.

PubMed

Badial, Peres R; Cisneros-Àlvarez, Luis Emiliano; Brandão, Cláudia Valéria S; Ranzani, José Joaquim T; Tomaz, Mayana A R V; Machado, Vania M; Borges, Alexandre S

2015-09-01

The aim of this study was to compare ocular dimensions, corneal curvature, and corneal thickness between horses affected with hereditary equine regional dermal asthenia (HERDA) and unaffected horses. Five HERDA-affected quarter horses and five healthy control quarter horses were used. Schirmer's tear test, tonometry, and corneal diameter measurements were performed in both eyes of all horses prior to ophthalmologic examinations. Ultrasonic pachymetry was performed to measure the central, temporal, nasal, dorsal, and ventral corneal thicknesses in all horses. B-mode ultrasound scanning was performed on both eyes of each horse to determine the dimensions of the ocular structures and to calculate the corneal curvature. Each corneal region examined in this study was thinner in the affected group compared with the healthy control group. However, significant differences in corneal thickness were only observed for the central and dorsal regions. HERDA-affected horses exhibited significant increases in corneal curvature and corneal diameter compared with unaffected animals. The ophthalmologic examinations revealed mild corneal opacity in one eye of one affected horse and in both eyes of three affected horses. No significant between-group differences were observed for Schirmer's tear test, intraocular pressure, or ocular dimensions. Hereditary equine regional dermal asthenia-affected horses exhibit decreased corneal thickness in several regions of the cornea, increased corneal curvature, increased corneal diameter, and mild corneal opacity. Additional research is required to determine whether the increased corneal curvature significantly impacts the visual accuracy of horses with HERDA. © 2014 American College of Veterinary Ophthalmologists.

Initial Low-Reynolds Number Iced Aerodynamic Performance for CRM Wing

NASA Technical Reports Server (NTRS)

Woodard, Brian; Diebold, Jeff; Broeren, Andy; Potapczuk, Mark; Lee, Sam; Bragg, Michael

2015-01-01

NASA, FAA, ONERA, and other partner organizations have embarked on a significant, collaborative research effort to address the technical challenges associated with icing on large scale, three-dimensional swept wings. These are extremely complex phenomena important to the design, certification and safe operation of small and large transport aircraft. There is increasing demand to balance trade-offs in aircraft efficiency, cost and noise that tend to compete directly with allowable performance degradations over an increasing range of icing conditions. Computational fluid dynamics codes have reached a level of maturity that they are being proposed by manufacturers for use in certification of aircraft for flight in icing. However, sufficient high-quality data to evaluate their performance on iced swept wings are not currently available in the public domain and significant knowledge gaps remain.

Heavy resistance training and peri-exercise ingestion of a multi-ingredient ergogenic nutritional supplement in males: effects on body composition, muscle performance and markers of muscle protein synthesis.

PubMed

Spillane, Mike; Schwarz, Neil; Willoughby, Darryn S

2014-12-01

This study determined the effects of heavy resistance training and peri-exercise ergogenic multi-ingredient nutritional supplement ingestion on blood and skeletal markers of muscle protein synthesis (MPS), body composition, and muscle performance. Twenty-four college-age males were randomly assigned to either a multi-ingredient SizeOn Maximum Performance (SIZE) or protein/carbohydrate/creatine (PCC) comparator supplement group in a double-blind fashion. Body composition and muscle performance were assessed, and venous blood samples and muscle biopsies were obtained before and after 6 weeks of resistance training and supplementation. Data were analyzed by 2-way ANOVA (p ≤ 0.05). Total body mass, body water, and fat mass were not differentially affected (p > 0.05). However, fat-free mass was significantly increased in both groups in response to resistance training (p = 0.037). Lower-body muscle strength (p = 0.029) and endurance (p = 0.027) were significantly increased with resistance training, but not supplementation (p > 0.05). Serum insulin, IGF-1, GH, and cortisol were not differentially affected (p > 0.05). Muscle creatine content was significantly increased in both groups from supplementation (p = 0.044). Total muscle protein (p = 0.038), MHC 1 (p = 0.041), MHC 2A, (p = 0.029), total IRS- (p = 0.041), and total Akt (p = 0.011) were increased from resistance training, but not supplementation. In response to heavy resistance training when compared to PCC, the peri-exercise ingestion of SIZE did not preferentially improve body composition, muscle performance, and markers indicative of MPS. Key pointsIn response to 42 days of heavy resistance training and either SizeOn Maximum Performance or protein/carbohydrate/creatine supplementation, similar increases in muscle mass and strength in both groups occurred; however, the increases were not different between supplement groups.The supplementation of SizeOn Maximum Performance had no preferential effect on augmenting serum insulin, IGF-1, and GH, or in decreasing cortisol.While resistance training was effective in increasing total creatine content in skeletal muscle, myofibrillar protein, and the content of total IRS-1 and Akt, it was not preferentially due to SizeOn Maximum Performance supplementation.At the daily dose of 50 g, SizeOn Maximum Performance supplementation for 42 days combined with resistance training does not increases muscle mass and strength due to its ability to elevate serum hormones and growth factors or in its ability to augment skeletal muscle signaling pathway markers indicative of muscle protein synthesis when compared to an equivalent daily dose of protein/carbohydrate/creatine.

Effects of Plyometric Versus Concentric and Eccentric Conditioning Contractions on Upper-Body Postactivation Potentiation.

PubMed

Ulrich, Gert; Parstorfer, Mario

2017-07-01

There are limited data on postactivation potentiation's (PAP) effects after plyometric conditioning contractions (CCs), especially in the upper body. This study compared plyometric CCs with concentric-eccentric and eccentric CCs aiming to improve upper-body power performance due to a PAP effect. Sixteen resistance-trained males completed 3 experimental trials in a randomized order that comprised either a plyometric (PLY), a concentric-eccentric (CON), or an eccentric-only (ECC) CC. Maximal muscle performance, as determined by a ballistic bench-press throw, was measured before (baseline) and 1, 4, 8, 12, and 16 min after each CC. Compared with baseline, bench-press power was significantly enhanced only in CON (P = .046, ES = 0.21) after 8 min of recovery. However, the results obtained from the comparisons between baseline power performance and the individual best power performance for each subject after each CC stimulus showed significant increases in PLY (P < .001, ES = 0.31) and CON (P < .001, ES = 0.38). There was no significant improvement in ECC (P = .106, ES = 0.11). The results indicate that only CON CCs generated increases in bench-press power after 8 min of rest. However, considering an individual rest interval, PLY CCs led to an enhanced power performance in the bench-press exercise, and this increase was comparable to that induced by CON CCs. Due to the easy practical application before a competition, PLY CCs might be an interesting part of warm-up strategies aiming to improve upper-body power performance by reason of PAP.

Traffic signal coordination and queue management in oversaturated intersection.

DOT National Transportation Integrated Search

2011-03-18

Traffic signal timing optimization when done properly, could significantly improve network : performance by reducing delay, increasing network throughput, reducing number of stops, or : increasing average speed in the network. The optimization can be...

Traffic signal coordination and queue management in oversaturated intersections.

DOT National Transportation Integrated Search

2011-03-18

Traffic signal timing optimization when done properly, could significantly improve network performance by reducing delay, increasing network throughput, reducing number of stops, or increasing average speed in the network. The optimization can become...

Complex dynamics in the distribution of players’ scoring performance in Rugby Union world cups

NASA Astrophysics Data System (ADS)

Seuront, Laurent

2013-09-01

The evolution of the scoring performance of Rugby Union players is investigated over the seven rugby world cups (RWC) that took place from 1987 to 2011, and a specific attention is given to how they may have been impacted by the switch from amateurism to professionalism that occurred in 1995. The distribution of the points scored by individual players, Ps, ranked in order of performance were well described by the simplified canonical law Ps∝(, where r is the rank, and ϕ and α are the parameters of the distribution. The parameter α did not significantly change from 1987 to 2007 (α=0.92±0.03), indicating a negligible effect of professionalism on players’ scoring performance. In contrast, the parameter ϕ significantly increased from ϕ=1.32 for 1987 RWC, ϕ=2.30 for 1999 to 2003 RWC and ϕ=5.60 for 2007 RWC, suggesting a progressive decrease in the relative performance of the best players. Finally, the sharp decreases observed in both α(α=0.38) and ϕ(ϕ=0.70) in the 2011 RWC indicate a more even distribution of the performance of individuals among scorers, compared to the more heterogeneous distributions observed from 1987 to 2007, and suggest a sharp increase in the level of competition leading to an increase in the average quality of players and a decrease in the relative skills of the top players. Note that neither α nor ϕ significantly correlate with traditional performance indicators such as the number of points scored by the best players, the number of games played by the best players, the number of points scored by the team of the best players or the total number of points scored over each RWC. This indicates that the dynamics of the scoring performance of Rugby Union players is influenced by hidden processes hitherto inaccessible through standard performance metrics; this suggests that players’ scoring performance is connected to ubiquitous phenomena such as anomalous diffusion.

Ameliorative effect of synthetic γ-aminobutyric acid (GABA) on performance traits, antioxidant status and immune response in broiler exposed to cyclic heat stress.

PubMed

Chand, Naila; Muhammad, Sher; Khan, Rifat Ullah; Alhidary, Ibrahim Abdullah; Rehman, Zia Ur

2016-12-01

The aim of this study was to find the effect of synthetic γ-aminobutyric acid (GABA) on the performance, antioxidant status, and immune response in broiler exposed to summer stress. A total of 400-day-old male broiler chickens (Ross 308) was randomly distributed into five treatments (5 replicates). One group served as a control (basal diet only) while the others were supplemented with GABA at the rate of 25 (GABA-25), 50 (GABA 50), 75 (GABA-75), and 100 (GABA-100) mg/kg feed. The experiment was continued for 35 days. Feed intake during the third week was significantly higher (P < 0.05) in GABA-75 and GABA-100, however, it increased significantly (P < 0.05) in GABA-100 during the fourth and fifth week. Overall mean feed intake was significantly (P < 0.05) high in GABA-75 and GABA-100. From the results, we found that body weight improved significantly (P < 0.05) in GABA-50 in week-3. During the fourth, fifth, and overall, body weight increased significantly (P < 0.05) in GABA-100. Significantly, high (P < 0.05) feed conversion ratio (FCR) was found in GABA-100 during the third, fourth, fifth, and on an overall basis. Mean Malondialdehyde (MDA) decreased significantly (P < 0.05) in GABA-100 while Paraoxonase (PON1) and Newcastle disease (ND) titer increased significantly (P < 0.05) in the same group. We concluded that performance traits, antioxidant status, and immune response improved in broiler supplemented 100 mg/kg GABA, exposed to cyclic heat stress.

Electroencephalogram associations to cognitive performance in clinically active nurses.

PubMed

Lees, Ty; Khushaba, Rami; Lal, Sara

2016-07-01

Cognitive impairment is traditionally identified via cognitive screening tools that have limited ability in detecting early or transitional stages of impairment. The dynamic nature of physiological variables such as the electroencephalogram (EEG) may provide alternate means for detecting these transitions. However, previous research examining EEG and cognitive performance is largely confined to samples with diagnosed cognitive impairments, and research examining non-impaired, and occupation specific samples, is limited. The present study aimed to investigate the associations between frontal pole and central EEG and cognitive performance in a sample of male and female nurses, and to determine the significance of these associations. Fifty seven nurses participated in the study, in which two lead bipolar EEG was recorded at positions Fp1 (frontal polar), Fp2, C3 (central) and C4 during a baseline and an active phase involving the common neuropsychological Stroop test. Participants' cognitive performance was assessed using the mini-mental state exam (MMSE) and Cognistat screening tools. Significant correlations between EEG beta activity and the outcome of MMSE and Cognistat were revealed, where an increased beta activity was associated to an increased global cognitive performance. Additionally, domain specific cognitive performance was also significantly associated to various EEG variables. The study identified potential EEG biomarkers for global and domain specific cognitive performance, and provides initial groundwork for the development of future EEG based biomarkers for detection of cognitive pathologies.

Can short-term oral fine motor training affect precision of task performance and induce cortical plasticity of the jaw muscles?

PubMed

Zhang, Hong; Kumar, Abhishek; Kothari, Mohit; Luo, Xiaoping; Trulsson, Mats; Svensson, Krister G; Svensson, Peter

2016-07-01

The aim was to test the hypothesis that short-term oral sensorimotor training of the jaw muscles would increase the precision of task performance and induce neuroplastic changes in the corticomotor pathways, related to the masseter muscle. Fifteen healthy volunteers performed six series with ten trials of an oral sensorimotor task. The task was to manipulate and position a spherical chocolate candy in between the anterior teeth and split it into two equal halves. The precision of the task performance was evaluated by comparing the ratio between the two split halves. A series of "hold-and-split" tasks was also performed before and after the training. The hold force and split force along with the electromyographic (EMG) activity of jaw muscles were recorded. Motor-evoked potentials and cortical motor maps of the right masseter muscle were evoked by transcranial magnetic stimulation. There was a significant effect of series on the precision of the task performance during the short-term oral sensorimotor training (P < 0.002). The hold force during the "hold-and-split" task was significantly lower after training than before the short-term training (P = 0.011). However, there was no change in the split force and the EMG activity of the jaw muscles before and after the training. Further, there was a significant increase in the amplitude of the motor-evoked potentials (P < 0.016) and in the motor cortex map areas (P = 0.033), after the short-term oral sensorimotor training. Therefore, short-term oral sensorimotor task training increased the precision of task performance and induced signs of neuroplastic changes in the corticomotor pathways, related to the masseter muscle.

Biological Interactions and Simulated Climate Change Modulates the Ecophysiological Performance of Colobanthus quitensis in the Antarctic Ecosystem

PubMed Central

Torres-Díaz, Cristian; Gallardo-Cerda, Jorge; Lavin, Paris; Oses, Rómulo; Carrasco-Urra, Fernando; Atala, Cristian; Acuña-Rodríguez, Ian S.; Convey, Peter; Molina-Montenegro, Marco A.

2016-01-01

Most climate and environmental change models predict significant increases in temperature and precipitation by the end of the 21st Century, for which the current functional output of certain symbioses may also be altered. In this context we address the following questions: 1) How the expected changes in abiotic factors (temperature, and water) differentially affect the ecophysiological performance of the plant Colobanthus quitensis? and 2) Will this environmental change indirectly affect C. quitensis photochemical performance and biomass accumulation by modifying its association with fungal endophytes? Plants of C. quitensis from King George Island in the South Shetland archipelago (62°09′ S), and Lagotellerie Island in the Antarctic Peninsula (65°53′ S) were put under simulated abiotic conditions in growth chambers following predictive models of global climate change (GCC). The indirect effect of GCC on the interaction between C. quitensis and fungal endophytes was assessed in a field experiment carried out in the Antarctica, in which we eliminated endophytes under contemporary conditions and applied experimental watering to simulate increased precipitation input. We measured four proxies of plant performance. First, we found that warming (+W) significantly increased plant performance, however its effect tended to be less than watering (+W) and combined warming and watering (+T°+W). Second, the presence of fungal endophytes improved plant performance, and its effect was significantly decreased under experimental watering. Our results indicate that both biotic and abiotic factors affect ecophysiological performance, and the directions of these influences will change with climate change. Our findings provide valuable information that will help to predict future population spread and evolution through using ecological niche models under different climatic scenarios. PMID:27776181

Biological Interactions and Simulated Climate Change Modulates the Ecophysiological Performance of Colobanthus quitensis in the Antarctic Ecosystem.

PubMed

Torres-Díaz, Cristian; Gallardo-Cerda, Jorge; Lavin, Paris; Oses, Rómulo; Carrasco-Urra, Fernando; Atala, Cristian; Acuña-Rodríguez, Ian S; Convey, Peter; Molina-Montenegro, Marco A

2016-01-01

Most climate and environmental change models predict significant increases in temperature and precipitation by the end of the 21st Century, for which the current functional output of certain symbioses may also be altered. In this context we address the following questions: 1) How the expected changes in abiotic factors (temperature, and water) differentially affect the ecophysiological performance of the plant Colobanthus quitensis? and 2) Will this environmental change indirectly affect C. quitensis photochemical performance and biomass accumulation by modifying its association with fungal endophytes? Plants of C. quitensis from King George Island in the South Shetland archipelago (62°09' S), and Lagotellerie Island in the Antarctic Peninsula (65°53' S) were put under simulated abiotic conditions in growth chambers following predictive models of global climate change (GCC). The indirect effect of GCC on the interaction between C. quitensis and fungal endophytes was assessed in a field experiment carried out in the Antarctica, in which we eliminated endophytes under contemporary conditions and applied experimental watering to simulate increased precipitation input. We measured four proxies of plant performance. First, we found that warming (+W) significantly increased plant performance, however its effect tended to be less than watering (+W) and combined warming and watering (+T°+W). Second, the presence of fungal endophytes improved plant performance, and its effect was significantly decreased under experimental watering. Our results indicate that both biotic and abiotic factors affect ecophysiological performance, and the directions of these influences will change with climate change. Our findings provide valuable information that will help to predict future population spread and evolution through using ecological niche models under different climatic scenarios.

Exposure reduces negative bias in self-rated performance in public speaking fearful participants.

PubMed

Cheng, Joyce; Niles, Andrea N; Craske, Michelle G

2017-03-01

Individuals with public speaking anxiety (PSA) under-rate their performance compared to objective observers. The present study examined whether exposure reduces the discrepancy between self and observer performance ratings and improved observer-rated performance in individuals with PSA. PSA participants gave a speech in front of a small audience and rated their performance using a questionnaire before and after completing repeated exposures to public speaking. Non-anxious control participants gave a speech and completed the questionnaire one time only. Objective observers watched videos of the speeches and rated performance using the same questionnaire. PSA participants underrated their performance to a greater degree than did controls prior to exposure, but also performed significantly more poorly than did controls when rated objectively. Bias significantly decreased and objective-rated performance significantly increased following completion of exposure in PSA participants, and on one performance measure, anxious participants no longer showed a greater discrepancy between self and observer performance ratings compared to controls. The study employed non-clinical student sample, but the results should be replicated in clinical anxiety samples. These findings indicate that exposure alone significantly reduces negative performance bias among PSA individuals, but additional exposure or additional interventions may be necessary to fully correct bias and performance deficits. Copyright © 2016 Elsevier Ltd. All rights reserved.

Match-derived relative pitch area changes the physical and team tactical performance of elite soccer players in small-sided soccer games.

PubMed

Olthof, Sigrid B H; Frencken, Wouter G P; Lemmink, Koen A P M

2018-07-01

Small-sided games (SSGs) are used in training sessions to prepare for full-sized matches. For the same number of players, smaller pitch sizes result in decreased physical performance and shorter interpersonal distances. A relative pitch area derived from the full-sized match results in larger pitch sizes and this may increase the fit between SSGs and full-sized matches. This study aimed to investigate SSGs with a traditional small pitch and a match-derived relative pitch area in youth elite soccer players. Four age categories (under-13, under-15, under-17 and under-19) played 4 vs. 4 plus goalkeepers on a small (40x30m, 120m 2 relative pitch area) and large pitch (68x47m, 320m 2 relative pitch area). The number of games per age category ranged 15-30. Positional data (LPM-system) were collected to determine physical (total distance covered, high intensity distance and number of sprints) and team tactical (inter-team distance, LPW-ratio, surface area, stretch indices, goalkeeper-defender distance) performance measures and tactical variability. On a large pitch, physical performance significantly increased, inter-team and intra-team distances were significantly larger and tactical variability of intra-team distance measures significantly increased. The match-derived relative pitch area is an important training manipulation and leads to changes in physical and tactical performance 4 vs. 4 plus goalkeepers.

Effects of repeated snowboard exercise in virtual reality with time lags of visual scene behind body rotation on head stability and subjective slalom run performance in healthy young subjects.

PubMed

Wada, Yoshiro; Nishiike, Suetaka; Kitahara, Tadashi; Yamanaka, Toshiaki; Imai, Takao; Ito, Taeko; Sato, Go; Matsuda, Kazunori; Kitamura, Yoshiaki; Takeda, Noriaki

2016-11-01

After repeated snowboard exercises in the virtual reality (VR) world with increasing time lags in trials 3-8, it is suggested that the adaptation to repeated visual-vestibulosomatosensory conflict in the VR world improved dynamic posture control and motor performance in the real world without the development of motion sickness. The VR technology was used and the effects of repeated snowboard exercise examined in the VR world with time lags between visual scene and body rotation on the head stability and slalom run performance during exercise in healthy subjects. Forty-two healthy young subjects participated in the study. After trials 1 and 2 of snowboard exercise in the VR world without time lag, trials 3-8 were conducted with 0.1, 0.2, 0.3, 0.4, 0.5, and 0.6 s time lags of the visual scene that the computer creates behind board rotation, respectively. Finally, trial 9 was conducted without time lag. Head linear accelerations and subjective slalom run performance were evaluated. The standard deviations of head linear accelerations in inter-aural direction were significantly increased in trial 8, with a time lag of 0.6 s, but significantly decreased in trial 9 without a time lag, compared with those in trial 2 without a time lag. The subjective scores of slalom run performance were significantly decreased in trial 8, with a time lag of 0.6 s, but significantly increased in trial 9 without a time lag, compared with those in trial 2 without a time lag. Motion sickness was not induced in any subjects.

The IGF-1/cortisol ratio as a useful marker for monitoring training in young boxers

PubMed Central

Nassib, S; Moalla, W; Hammoudi-Nassib, S; Chtara, M; Hachana, Y; Tabka, Z; Chamari, K

2015-01-01

Training effects on plasma insulin-like growth factor-1 (IGF-1)/cortisol ratio were investigated in boxers. Thirty subjects were assigned to either the training or the control group (n = 15 in both). They were tested before the beginning of training (T0), after 5 weeks of intensive training (T1), and after 1 week of tapering (T2). Physical performances (Yo-Yo intermittent recovery test level-1), training loads, and blood sampling were obtained at T0, T1, and T2. Controls were only tested for biochemical and anthropometric parameters at T0 and T2. A significantly higher physical performance was observed at T2 compared to T1. At T1, cortisol levels were significantly increased whereas IGF-1 and insulin-like growth factor binding protein-3 (IGFBP-3) levels remained unchanged compared to baseline. At T2, cortisol levels decreased while IGF-1 and IGFBP-3 levels increased. The IGF-1/cortisol ratio decreased significantly at T1 and increased at T2, and its variations were significantly correlated with changes in training loads and Yo-Yo intermittent recovery test level 1 (IRT1) performance over the training period. Cortisol variations correlated with changes in training load (r = 0.64; p < 0.01) and Yo-Yo IRT1 performance (r = 0.78; p < 0.001) at T1 whereas IGF-1 variations correlated only with changes in Yo-Yo IRT1 performance at T2 (r = 0.71; p < 0.001). It is concluded that IGF-1/cortisol ratio could be a useful tool for monitoring training loads in young trained boxers. PMID:26985129

Kinematic effects of a short-term fatigue protocol on punt-kicking performance.

PubMed

Coventry, Evan; Ball, Kevin; Parrington, Lucy; Aughey, Robert; McKenna, Michael

2015-01-01

The punt kick is a fundamental skill used in several team sports; however, there has been a lack of research on how fatigue affects its technique. The purpose of this study was to determine the effects of short-term fatigue on punt-kicking performance. Eight elite and sub-elite Australian Football players performed maximal drop punt kicks on their preferred leg prior to, during and after a match-specific fatigue protocol. Optotrak Certus collected kinematic data from kick foot toe-off until ball contact. Repeated-measures analysis of variance showed a significant increase in 20 m sprint times after each short-term protocol, indicating fatigue. Foot speed did not significantly change with fatigue; however, increases in the range of motion at the pelvis and kicking thigh, along with increases in kicking thigh angular velocity, occurred. For the support leg, maximum knee flexion angular velocity increased while there was greater flexion found at the knee and hip, and greater range of motion at the knee. Players are able to make kinematic adaptations in order to maintain foot speed while punting for maximal distance after short-term efforts.

Hybrid fuel formulation and technology development

NASA Technical Reports Server (NTRS)

Dean, D. L.

1995-01-01

The objective was to develop an improved hybrid fuel with higher regression rate, a regression rate expression exponent close to 0.5, lower cost, and higher density. The approach was to formulate candidate fuels based on promising concepts, perform thermomechanical analyses to select the most promising candidates, develop laboratory processes to fabricate fuel grains as needed, fabricate fuel grains and test in a small lab-scale motor, select the best candidate, and then scale up and validate performance in a 2500 lbf scale, 11-inch diameter motor. The characteristics of a high performance fuel have been verified in 11-inch motor testing. The advanced fuel exhibits a 15% increase in density over an all hydrocarbon formulation accompanied by a 50% increase in regression rate, which when multiplied by the increase in density yields a 70% increase in fuel mass flow rate; has a significantly lower oxidizer-to-fuel (O/F) ratio requirement at 1.5; has a significantly decreased axial regression rate variation making for more uniform propellant flow throughout motor operation; is very clean burning; extinguishes cleanly and quickly; and burns with a high combustion efficiency.

Instruction of jump-landing technique using videotape feedback: altering lower extremity motion patterns.

PubMed

Oñate, James A; Guskiewicz, Kevin M; Marshall, Stephen W; Giuliani, Carol; Yu, Bing; Garrett, William E

2005-06-01

Anterior cruciate ligament injury prevention programs have used videotapes of jump-landing technique as a key instructional component to improve landing performance. All videotape feedback model groups will increase knee flexion angles at initial contact and overall knee flexion motion and decrease peak vertical ground reaction forces and peak proximal anterior tibial shear forces to a greater extent than will a nonfeedback group. The secondary hypothesis is that the videotape feedback using the combination of the expert and self models will create the greatest change in each variable. Controlled laboratory study. Knee kinematics and kinetics of college-aged recreational athletes randomly placed in 3 different videotape feedback model groups (expert only, self only, combination of expert and self) and a nonfeedback group were collected while participants performed a basketball jump-landing task on 3 testing occasions. All feedback groups significantly increased knee angular displacement flexion angles [F(6,70) = 8.03, P = .001] and decreased peak vertical ground reaction forces [F(6,78) = 2.68, P = .021] during performance and retention tests. The self and combination groups significantly increased knee angular displacement flexion angles more than the control group did; the expert model group did not change significantly more than the control group did. All feedback groups and the nonfeedback group significantly reduced peak vertical forces across performance and retention tests. There were no statistically significant changes in knee flexion angle at initial ground contact (P = .111) and peak proximal anterior tibial shear forces (P = .509) for both testing sessions for each group. The use of self or combination videotape feedback is most useful for increasing knee angular displacement flexion angles and reducing peak vertical forces during landing. The use of self or combination modeling is more effective than is expert-only modeling for the implementation of instructional programs aimed at reducing the risk of jump-landing anterior cruciate ligament injuries.

Effects of Khaya senegalensis leaves on performance, carcass traits, hemtological and biochemical parameters in rabbits

PubMed Central

Abdel-Wareth, A. A. A.; Hammad, Seddik; Ahmed, Hassan

2014-01-01

One of the challenges facing farmers today is to ensure adequate integration of natural resources into animal feeds. The aim of the present study is to evaluate the effects of Khaya senegalensis (KS) leaves on the performance of growing male rabbits, carcass traits and biochemical as well as hematological parameters. Thirty New Zealand White male growing rabbits were randomly divided into 3 groups (10 rabbits per group). Group I (control) received standard rabbit diet. Rabbits in group II and group III were fed standard rabbit diet supplemented with 35 % and 65 % KS leaves, respectively. All rabbits were fed daily for 25 days. The performance parameters and carcass criteria, including daily body weight gain, final body weight, and the percentage of dressing, were increased in rabbits fed 35 % KS when compared to the control group. Kidney and liver weight ratios increased significantly in group II but dropped in group III. Furthermore, liver enzymes - alanine aminotransferase and aspartate transaminase and kidney function parameters - urea, and creatinine - increased in both group II (significant P<0.05) and in group III (significant P<0.01) when compared to the control group. Moreover, KS leaves induced a significant increase (P<0.05) in the total white blood cell count, the percentage of granulocytes and the platelet count; whereas, the percentage of lymphocytes, red blood cell count, hemoglobin content, mean corpuscular hemoglobin, mean corpuscular volume and mean corpuscular hemoglobin concentration were not statistically significantly changed. This study demonstrates that the performance parameters and carcass traits are improved by the replacement of rabbit's diet with KS leaves. However, KS leaves may adversely affect liver and kidney function in a dose-dependent manner. Therefore, further studies are required to elucidate the maximum tolerable and toxic, as well as lethal doses, and to isolate the pharmacologically active components from KS leaves. PMID:26417277

The effects of passive leg press training on jumping performance, speed, and muscle power.

PubMed

Liu, Chiang; Chen, Chuan-Shou; Ho, Wei-Hua; Füle, Róbert János; Chung, Pao-Hung; Shiang, Tzyy-Yuang

2013-06-01

Passive leg press (PLP) training was developed based on the concepts of the stretch-shortening cycle (SSC) and the benefits of high muscle contraction velocity. Passive leg press training enables lower limb muscle groups to apply a maximum downward force against a platform moved up and down at high frequency by an electric motor. Thus, these muscle groups accomplished both concentric and eccentric isokinetic contractions in a passive, rapid, and repetitive manner. This study investigates the effects of 10 weeks of PLP training at high and low movement frequencies have on jumping performance, speed, and muscle power. The authors selected 30 college students who had not performed systematic resistance training in the previous 6 months, including traditional resistance training at a squat frequency of 0.5 Hz, PLP training at a low frequency of 0.5 Hz, and PLP training at a high frequency of 2.5 Hz, and randomly divided them into 3 groups (n = 10). The participants' vertical jump, drop jump, 30-m sprint performance, explosive force, and SSC efficiency were tested under the same experimental procedures at pre- and post-training. Results reveal that high-frequency PLP training significantly increased participants' vertical jump, drop jump, 30-m sprint performance, instantaneous force, peak power, and SSC efficiency (p < 0.05). Additionally, their change rate abilities were substantially superior to those of the traditional resistance training (p < 0.05). The low-frequency PLP training significantly increased participants' vertical jump, 30-m sprint performance, instantaneous force, and peak power (p < 0.05). However, traditional resistance training only increased participants' 30-m sprint performance and peak power (p < 0.05). The findings suggest that jump performance, speed, and muscle power significantly improved after 10 weeks of PLP training at high movement frequency. A PLP training machine powered by an electrical motor enables muscles of the lower extremities to contract faster compared with voluntary contraction. Therefore, muscle training with high contraction velocity is one of the main methods of increasing muscle power. Passive leg press training is a unique method for enhancing jump performance, speed, and muscle power.

Opinion and Special Articles: Stress when performing the first lumbar puncture may compromise patient safety.

PubMed

Henriksen, Mikael Johannes Vuokko; Wienecke, Troels; Kristiansen, Jesper; Park, Yoon Soo; Ringsted, Charlotte; Konge, Lars

2018-05-22

To quantify physician stress levels when performing lumbar puncture (LP) and explore operator stress effect on patient outcomes. This was a cross-sectional, multicenter study. Novices, intermediates, and experts in performing LP were recruited from 4 departments of neurology and emergency medicine. Stress was measured before and during performance of the LP using cognitive appraisal (CA), State-Trait Anxiety Inventory-Short (STAI-S) questionnaire, and the heart rate variability measure low frequency/high frequency index (LF/HF ratio). Patient-related outcomes were pain, confidence in the operator, and postdural puncture headache (PDPH). Forty-six physicians were included in the study: 22 novices, 12 intermediates, and 12 experts. Novices had the highest stress level and experts the lowest measured by cognitive appraisal and STAI-S before and during LP performance ( p < 0.001 for all comparisons). Novices had the highest sympathetic tonus indicated by the highest LF/HF ratio before ( p = 0.004) and during ( p = 0.056) LP performance. Physician stress level was not significantly related to patients' pain. However, there was a significant relationship between STAI-S during the procedure and patient confidence in the operator (regression coefficient = -0.034, p = 0.008). High physician heart rate during the procedure significantly increased the odds of PDPH (odds ratio = 1.17, p = 0.036). Novice stress levels were high before and during performance of LP. Stress was significantly related to patient confidence in the operator and risk of PDPH. Simulation-based training should be considered to reduce novice residents' stress levels and increase patient safety. © 2018 American Academy of Neurology.

Effect of dietary fish meal replacement by red algae, Gracilaria arcuata, on growth performance and body composition of Nile tilapia Oreochromis niloticus.

PubMed

Younis, El-Sayed M; Al-Quffail, Abdullah S; Al-Asgah, Nasser A; Abdel-Warith, Abdel-Wahab A; Al-Hafedh, Yousef S

2018-02-01

A 12-week long feeding experiment was initiated to evaluate the effect of dietary supplementation of red algae, Gracilaria arcuata , on the growth performance, feed utilization and body composition of Nile tilapia Oreochromis niloticus (Linnaeus, 1758). The fish were fed with an algae-free control diet (C) and three experimental diets which replaced conventional fish meal with varying levels of dried G. arcuata (20%, 40% and 60%, represented as G20, G40 and G60, respectively). The growth parameters of final weight (FW), weight gain (WG), percentage of weight gain (WG%), daily growth rate (DGR) and specific growth rate (SGR) were significantly reduced (P < 0.05) at all levels of algae incorporation compared to the control diet. Moreover, the negative impact of Gracilaria meal on the growth performance of Nile tilapia increased as the proportion of algae in the diet increased, with fish on diet G20 exhibiting a significantly higher growth performance than the fish on either of the G40 and G60 diets. On the other hand, the feed utilization parameters feed conversion ratio (FCR) and protein efficiency ratio (PER) did not show significant differences between the fish in the control group and those on diet G20, although poorer FCR and PER outcomes were achieved in the case of fish on diet G60. The content of moisture, protein and ash in muscle and carcass increased as the proportion of Gracilaria meal in the diets increased, but the reverse was true for lipid level. These results indicate that incorporation of less than 20% red algae, Gracilaria arcuata , could be feasible in the diet of Nile tilapia and further studies are recommended to optimize the level of algae to improve growth performance.

CH3NH3I post-treatment improves the performance of perovskite solar cells via eliminating the impure phases

NASA Astrophysics Data System (ADS)

Liang, Jingjing; Liang, Chunjun; Zhang, Huimin; Sun, Mengjie; Liu, Hong; Ji, Chao; Zhang, Xuewen; Li, Dan; He, Zhiqun

Organic-inorganic halide perovskites are currently generating extensive interest for applications in solar cells. The perovskite morphology and composition have significant roles in solar cells. Impure phases, which will influence the performance of solar cells, are inevitably present in the film of perovskite. We found that another MAI deposition on the previous perovskite could ameliorate the film. The post-deposited MAI participates in the reconstruction of the perovskite, leading to reduced amount of impure phase, increased grain size, increased absorption and significantly improved power conversion efficiency. The results demonstrate a treatment approach to fabricate efficient planar heterojunction perovskite solar cells.

Mental fatigue detection based on the functional near infrared spectroscopy

NASA Astrophysics Data System (ADS)

Zhang, Zhen; Xu, Fenggang; Yang, Hanjun; Jiang, Jin; Cao, Yong; Jiao, Xuejun

2017-02-01

Mental fatigue can be induced by long time mental work, mental fatigue caused worse performance and accidents. As a non-invasive technique, functional near-infrared spectroscopy (fNIRS) can measure blood oxygen activity in the cerebral cortex which reflect the cognitive function of brain indirectly. Aiming at investigating whether fNIRS can measure the mental fatigue and study the spatial pattern of hemodynamic response for mental fatigue, we used three sessions of verbal 2-back working memory task for a total of 120 minutes to induce mental fatigue, 15 healthy subjects were recruited and 30 channels including prefrontal cortex (PFC) and motor cortex (MC) were measured by fNIRS. The mean oxyhemoglobin feature for 20s was extracted as well as subjective fatigue level and performance. The results showed significant increase of subjected fatigue level as well as significant decrease performance from session one to three task. With the increased level of fatigue, oxyhemoglobin in PFC increase significantly and the spatial pattern of hemodynamic response in the all 30 channels varied with task duration as well. These findings indicated the potential of fNIRS measured hemodynamic as a mental fatigue indicator.

Do invasive alien plants benefit more from global environmental change than native plants?

PubMed

Liu, Yanjie; Oduor, Ayub M O; Zhang, Zhen; Manea, Anthony; Tooth, Ifeanna M; Leishman, Michelle R; Xu, Xingliang; van Kleunen, Mark

2017-08-01

Invasive alien plant species threaten native biodiversity, disrupt ecosystem functions and can cause large economic damage. Plant invasions have been predicted to further increase under ongoing global environmental change. Numerous case studies have compared the performance of invasive and native plant species in response to global environmental change components (i.e. changes in mean levels of precipitation, temperature, atmospheric CO 2 concentration or nitrogen deposition). Individually, these studies usually involve low numbers of species and therefore the results cannot be generalized. Therefore, we performed a phylogenetically controlled meta-analysis to assess whether there is a general pattern of differences in invasive and native plant performance under each component of global environmental change. We compiled a database of studies that reported performance measures for 74 invasive alien plant species and 117 native plant species in response to one of the above-mentioned global environmental change components. We found that elevated temperature and CO 2 enrichment increased the performance of invasive alien plants more strongly than was the case for native plants. Invasive alien plants tended to also have a slightly stronger positive response to increased N deposition and increased precipitation than native plants, but these differences were not significant (N deposition: P = 0.051; increased precipitation: P = 0.679). Invasive alien plants tended to have a slightly stronger negative response to decreased precipitation than native plants, although this difference was also not significant (P = 0.060). So while drought could potentially reduce plant invasion, increases in the four other components of global environmental change considered, particularly global warming and atmospheric CO 2 enrichment, may further increase the spread of invasive plants in the future. © 2017 John Wiley & Sons Ltd.

Born Small for Gestational Age and Poor School Performance - How Small Is Too Small?

PubMed

Lindström, Linda; Wikström, Anna-Karin; Bergman, Eva; Lundgren, Maria

2017-01-01

To assess the relationship between severity of small for gestational age (SGA) and the risk of poor school performance, and to investigate whether adult stature modifies this risk. 1,088,980 Swedish children born at term between 1973 and 1988 were categorized into severe SGA (less than -3 standard deviations (SD) of expected birth weight), moderate SGA (-2.01 to -3 SD), mild SGA (-1.01 to -2 SD), and appropriate for gestational age (-1 to 0.99 SD). The risk of poor school performance at the time of graduation from compulsory school (grades <10th percentile) was calculated using unconditional logistic regression models and adjusted for socio-economic factors. In a sub-analysis, we stratified boys by adult stature, and adjusted for maternal but not paternal height. All SGA groups were significantly associated with an increased risk of poor school performance, with adjusted odds ratios and 95% confidence intervals ranging from 1.85 (1.65-2.07) for severe SGA to 1.25 (1.22-1.28) for mild SGA. In the sub-analysis, all birth weight groups were associated with an increased risk of poor school performance among boys with short stature compared to those with non-short stature. Mild SGA is associated with a significantly increased risk of poor school performance, and the risk increases with severity of SGA. Further, this risk diminishes after adequate catch-up growth. © 2017 S. Karger AG, Basel.

The effect of increased classroom ventilation rate indicated by reduced CO2 concentration on the performance of schoolwork by children.

PubMed

Petersen, S; Jensen, K L; Pedersen, A L S; Rasmussen, H S

2016-06-01

The article reports on an experiment which investigated the effect of increased classroom ventilation rate on the performance of children aged 10-12 years. The experiment was executed at two different schools (two classrooms at each school) as a double-blind 2 × 2 crossover intervention where four different performance tests were used as surrogates for short-term concentration and logical thinking. Only complete pairs of test responses were included in the within-subject comparisons of performance, and data were not corrected for learning and fatigue effects. Analysis of the total sample suggested the number of correct answers was improved significantly in four of four performance test, addition (6.3%), number comparison (4.8%), grammatical reasoning (3.2%), and reading and comprehension (7.4%), when the outdoor air supply rate was increased from an average of 1.7 (1.4-2.0) to 6.6 l/s per person. The increased outdoor air supply rate did not have any significant effect on the number of errors in any of the performance tests. Results from questionnaires regarding pupil perception of the indoor environment, reported Sick Building Syndrome symptoms, and motivation suggested that the study classroom air was perceived more still and pupil were experiencing less pain in the eyes in the recirculation condition compared to the fresh air condition. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Social hierarchies and emotions: cortical prefrontal activity, facial feedback (EMG), and cognitive performance in a dynamic interaction.

PubMed

Balconi, Michela; Pagani, Silvia

2015-04-01

In the present research, we manipulated the perceived superior/inferior status during a competitive cognitive task. In two experiments, we created an explicit and strongly reinforced social hierarchy based on incidental rating on an attentional task. Based on our hypotheses, social rank may influence nonverbal cues (such as facial mimic related to emotional response), cortical lateralized activity in frontal areas (brain oscillations), and cognitive outcomes in response to rank modulation. Thus, the facial mimic (corrugators vs. zygomatic muscle activity), frequency bands (delta, theta, alpha, beta), and real cognitive performance [(error rate (ER); response times (RTs)] were considered. Specifically, a peer-group comparison was enrolled and an improved (experiment 1, N = 29) or decreased (experiment 2, N = 31) performance was artificially manipulated by the experimenter. Results showed a significant improved cognitive performance (decreased ER and RTs), an increased zygomatic activity (positive emotions), and a more prefrontal left-lateralized cortical response in the case of a perceived increased social ranking. On the contrary, a significant decreased cognitive performance (increased ER and RTs), an increased corrugators activity (negative emotions), and a less left-lateralized cortical response were observed as a consequence of a perceived decreased social ranking. Moreover, the correlational values revealed a consistent trend between behavioral (RTs) and EMG and EEG measures for both experiments. The present results suggest that social status not only guides social behavior, but it also influences cognitive processes and subjects' performance.

Thermal plasticity of diving behavior, aquatic respiration, and locomotor performance in the Mary River turtle Elusor macrurus.

PubMed

Clark, Natalie J; Gordos, Matthew A; Franklin, Craig E

2008-01-01

Locomotion is a common measure of performance used in studies of thermal acclimation because of its correlation with predator escape and prey capture. However, for sedentary animals such as freshwater turtles, we propose that diving behavior may be a more ecologically relevant measure of performance. Increasing dive duration in hatchling turtles reduces predator exposure and therefore functions as an ecological benefit. Diving behavior is thermally dependent, and in some species of freshwater turtles, it is also reliant on aquatic respiration. This study examined the influence of thermal acclimation on diving behavior, aquatic respiration, and locomotor performance in the endangered, bimodally respiring Mary River turtle Elusor macrurus. Diving behavior was found to partially acclimate at 17 degrees C, with turtles acclimated to a cold temperature (17 degrees C) having a significantly longer dive duration than hatchlings acclimated to a warm temperature (28 degrees C). This increase in dive duration at 17 degrees C was not a result of physiological alterations in metabolic rate but was due instead to an increase in aquatic oxygen consumption. Increasing aquatic oxygen consumption permitted cold-acclimated hatchlings to remain submerged for significantly longer periods, with one turtle undertaking a dive of over 2.5 d. When burst-swimming speed was used as the measure of performance, thermal acclimation was not detected. Overall, E. macrurus demonstrated a partial ability to acclimate to changes in environmental temperature.

Effects of Pilates Exercise on Salivary Secretory Immunoglobulin A Levels in Older Women.

PubMed

Hwang, Yoonyoung; Park, Jonghoon; Lim, Kiwon

2016-07-01

We examined the effects of a Pilates exercise program on the mucosal immune function in older women. The study population comprised 12 older women who were divided into a Pilates group (PG, n = 6) and a control group (CG, n = 6). Saliva samples were obtained from both groups before and after the experimental period for salivary secretory immunoglobulin A level measurement. In addition, acute high-intensity exercises were performed before and after the three-month Pilates exercise program. After three months, salivary flow was significantly higher in the PG than in the CG. After the acute high-intensity exercises were performed following the three-month Pilates exercise program, the salivary flow rate was significantly higher at all time points. The S-IgA secretion rate significantly increased 30 min after acute high-intensity exercise performed following the three-month Pilates exercise program. This study suggests that regular participation in a moderate-intensity Pilates exercise program can increase salivary flow rate and S-IgA secretion in older women.

Erupting with Great Force: Performing Text to Enhance Reading Comprehension

ERIC Educational Resources Information Center

Bullion-Mears, Ann; McCauley, Joyce K.; McWhorter, J. YeVette

2007-01-01

Performing text in the form of choral reading, rap, reader's theatre, and/or simulations offers students a powerful vehicle for understanding and recalling key concepts and significant details culled from textual materials. Creating a script, poem, or lyrics to perform requires repeated readings of a text, a practice that increases participants'…

Effects of prior warm-up regime on severe-intensity cycling performance.

PubMed

Burnley, Mark; Doust, Jonathan H; Jones, Andrew M

2005-05-01

The purpose of the present study was to determine the effect of three different warm-up regimes on cycling work output during a 7-min performance trial. After habituation to the experimental methods, 12 well-trained cyclists completed a series of 7-min performance trials, involving 2 min of constant-work rate exercise at approximately 90% VO2max and a further 5 min during which subjects attempted to maximize power output. This trial was performed without prior intervention and 10 min after bouts of moderate, heavy, or sprint exercise in a random order. Pulmonary gas exchange was measured breath by breath during all performance trials. At the onset of the performance trial, baseline blood [lactate] was significantly elevated after heavy and sprint but not moderate exercise (mean +/- SD: control, 1.0 +/- 0.3 mM; moderate, 1.0 +/- 0.2 mM; heavy, 3.0 +/- 1.1 mM; sprint, 5.9 +/- 1.5 mM). All three interventions significantly increased the amplitude of the primary VO2 response (control, 2.59 +/- 0.28 L x min(-1); moderate, 2.69 +/- 0.27 L x min(-1); heavy, 2.78 +/- 0.26 L x min(-1); sprint, 2.78 +/- 0.30 L x min(-1)). Mean power output was significantly increased by prior moderate and heavy exercise but not significantly reduced after sprint exercise (control, 330 +/- 42 W; moderate, 338 +/- 39 W; heavy, 339 +/- 42 W; sprint, 324 +/- 45 W). These data indicate that priming exercise performed in the moderate- and heavy-intensity domains can improve severe-intensity cycling performance by ~2-3%, the latter condition doing so despite a mild lactacidosis being present at exercise onset.

Importance of strategy in social media: getting the most out of your post

NASA Astrophysics Data System (ADS)

Bohon, W.; Sumy, D. F.

2016-12-01

Social media is playing an ever-increasing role in informal science education due to its broad and ubiquitous reach, low overhead costs and versatility. However, to fully capitalize on the educational potential and dissemination capabilities of social media platforms, science organizations with a social media presence must move forward with an effective strategy that clearly outlines their audience, goals, messaging, content and growth objectives. It is also imperative that organizations perform a regular, rigorous evaluation of social media platform performance and conduct user engagement surveys and that they utilize this information to improve online performance and engagement. Here, we examine the IRIS EPO Facebook and Twitter platforms before and after the adoption of a more formal and detailed social media strategy. Some of the most effective growth tools thus far have been the content posting schedule, content media type guidelines and periodic platform performance evaluation. We also examine the results of a user survey assessing the efficacy of the IRIS social media presence. In the 8 months since the implementation of the new, more rigorous social media strategy the IRIS Facebook page following has grown by more than 90% and the Twitter page following has increased by almost 75%. This is a significant increase in growth as compared to the preceding years, which corresponds to significant increase in reach (Figure 1). By implementing a defined strategy with clear goals, scientific organizations can fully harness the educational potential offered by social media networks. [Figure 1: Facebook provided metrics showing the reach of the IRIS EPO Facebook page between 7/21/2014 and 7/22/2016. Although there are spikes in post reach in 2015 corresponding to newsworthy earthquake events, a significant increase in sustained reach occurred beginning in Dec of 2105 when the IRIS social media strategy was implemented.

Frequency and complications after operative fixation of clavicular fractures.

PubMed

Navarro, Ronald A; Gelber, Jonathan D; Harrast, John J; Seiler, John G; Jackson, Kent R; Garcia, Ivan A

2016-05-01

The purpose of this study was to analyze whether a recent trend in evidence supporting operative treatment of clavicular fractures is matched with an increase in operative fixation and complication rates in the United States. The American Board of Orthopaedic Surgery database was reviewed for cases with Current Procedural Terminology (American Medical Association, Chicago, IL, USA) code 23515 (clavicle open reduction internal fixation [ORIF]) from 1999 to 2010. The procedure rate for each year and the number of procedures for each candidate performing clavicle ORIF were calculated to determine if a change had occurred in the frequency of ORIF for clavicular fractures. Complication and outcome data were also reviewed. In 2010 vs, 1999, there were statistically significant increases in the mean number of clavicle ORIF performed among all candidates (0.89 vs. 0.13; P < .0001) and in the mean number of clavicle ORIF per candidate performing clavicle ORIF (2.47 vs. 1.20, P < .0473). The difference in the percentage of part II candidates performing clavicle ORIF from the start to the end of the study (11% vs. 36%) was significant (P < .0001). There was a significant increase in the clavicle ORIF percentage of total cases (0.11% vs. 0.74%, P < .0001). The most common complication was hardware failure (4%). The rate of ORIF of clavicular fractures has increased in candidates taking part II of the American Board of Orthopaedic Surgery, with a low complication rate. The increase in operative fixation during this interval may have been influenced by literature suggesting improved outcomes in patients treated with operative stabilization of their clavicular fracture. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Climate change and the impact of extreme temperatures on aviation

NASA Astrophysics Data System (ADS)

Coffel, E.; Horton, R.

2014-12-01

Weather is the most significant factor affecting aircraft operations, accounting for 70-80% of passenger delays and costing airlines hundreds of millions of dollars per year in lost revenue. Temperature and airport elevation significantly influence the maximum allowable takeoff weight of an aircraft by changing the surface air density and thus the lift produced at a given speed. For a given runway length, airport elevation, and aircraft type there is a temperature threshold above which the airplane cannot take off at its maximum weight and thus must be weight restricted. The number of summer days necessitating weight restriction has increased since 1980 along with the observed increase in surface temperature. Climate change is projected to increase mean temperatures at all airports and significantly increase the frequency and severity of extreme heat events at some. These changes will negatively affect aircraft performance, leading to increased weight restrictions especially at airports with short runways and little room to expand. For a Boeing 737-800 aircraft, we find that the number of weight restriction days between May and September will increase by 50-100% at four major airports in the United States by 2050-2070 under the RCP8.5 high emissions scenario. These performance reductions may have a significant economic effect on the airline industry, leading to lower profits and higher passenger fares. Increased weight restrictions have previously been identified as potential impacts of climate change, but this study is the first to quantify the effect of higher temperatures on commercial aviation.

Effects of precision demands and mental pressure on muscle activation and hand forces in computer mouse tasks.

PubMed

Visser, Bart; De Looze, Michiel; De Graaff, Matthijs; Van Dieën, Jaap

2004-02-05

The objective of the present study was to gain insight into the effects of precision demands and mental pressure on the load of the upper extremity. Two computer mouse tasks were used: an aiming and a tracking task. Upper extremity loading was operationalized as the myo-electric activity of the wrist flexor and extensor and of the trapezius descendens muscles and the applied grip- and click-forces on the computer mouse. Performance measures, reflecting the accuracy in both tasks and the clicking rate in the aiming task, indicated that the levels of the independent variables resulted in distinguishable levels of accuracy and work pace. Precision demands had a small effect on upper extremity loading with a significant increase in the EMG-amplitudes (21%) of the wrist flexors during the aiming tasks. Precision had large effects on performance. Mental pressure had substantial effects on EMG-amplitudes with an increase of 22% in the trapezius when tracking and increases of 41% in the trapezius and 45% and 140% in the wrist extensors and flexors, respectively, when aiming. During aiming, grip- and click-forces increased by 51% and 40% respectively. Mental pressure had small effects on accuracy but large effects on tempo during aiming. Precision demands and mental pressure in aiming and tracking tasks with a computer mouse were found to coincide with increased muscle activity in some upper extremity muscles and increased force exertion on the computer mouse. Mental pressure caused significant effects on these parameters more often than precision demands. Precision and mental pressure were found to have effects on performance, with precision effects being significant for all performance measures studied and mental pressure effects for some of them. The results of this study suggest that precision demands and mental pressure increase upper extremity load, with mental pressure effects being larger than precision effects. The possible role of precision demands as an indirect mental stressor in working conditions is discussed.

Effect of Chronic Diseases on Work Productivity: A Propensity Score Analysis.

PubMed

Fouad, Ahmed Mahmoud; Waheed, Amani; Gamal, Amira; Amer, Shaimaa Ahmed; Abdellah, Rasha Farouk; Shebl, Fatma Mohamed

2017-05-01

The aim of this study was to evaluate the effect of chronic disease(s) on work productivity. Using the Health & Work Performance Questionnaire, information was collected from 516 workers on chronic disease status and work productivity. Propensity-score matching was performed to identify matched-pairs of workers. In the propensity-score matched sample, workers with chronic diseases were more likely to have increased absenteeism and presenteeism rates, 6.34 and 2.36 times the rates if no chronic diseases, respectively. In addition, they had greater odds for getting negative critical work incidents and less odds for positive incidents than none or balanced status. Multimorbidity showed more significant increase in absenteeism and presenteeism rates, as well as increased odds for excess negative critical work incidents. Chronic disease(s) can significantly reduce work productivity by increasing absenteeism, presenteeism, and net negative critical incidents.

Multi-task functional MRI in multiple sclerosis patients without clinical disability.

PubMed

Colorado, René A; Shukla, Karan; Zhou, Yuxiang; Wolinsky, Jerry S; Narayana, Ponnada A

2012-01-02

While the majority of individuals with multiple sclerosis (MS) develop significant clinical disability, a subset experiences a disease course with minimal impairment even in the presence of significant apparent tissue damage on magnetic resonance imaging (MRI). Functional magnetic resonance imaging (fMRI) in MS patients with low disability suggests that increased use of the cognitive control system may limit the clinical manifestation of the disease. The current fMRI studies tested the hypothesis that nondisabled MS patients show increased recruitment of cognitive control regions while performing sensory, motor and cognitive tasks. Twenty two patients with relapsing-remitting MS and an Expanded Disability Status Scale (EDSS) score of ≤1.5 and 23 matched healthy controls were recruited. Subjects underwent fMRI while observing flashing checkerboards, performing right or left hand movements, or executing the 2-back working memory task. Compared to control subjects, patients demonstrated increased activation of the right dorsolateral prefrontal cortex and anterior cingulate cortex during the performance of the working memory task. This pattern of functional recruitment also was observed during the performance of non-dominant hand movements. These results support the mounting evidence of increased functional recruitment of cognitive control regions in the working memory system of MS patients with low disability and provide new evidence for the role of increased cognitive control recruitment in the motor system. Copyright © 2011 Elsevier Inc. All rights reserved.

A longitudinal study evaluating the effects of interferon-alpha therapy on cognitive and psychiatric function in adults with chronic hepatitis C

PubMed Central

Huckans, Marilyn; Fuller, Bret; Wheaton, Viva; Jaehnert, Sarah; Ellis, Carilyn; Kolessar, Michael; Kriz, Daniel; Anderson, Jeanne Renee; Berggren, Kristin; Olavarria, Hannah; Sasaki, Anna W.; Chang, Michael; Flora, Kenneth D.; Loftis, Jennifer M.

2015-01-01

Objective To prospectively evaluate for changes in objective cognitive performance (attention, memory, and executive function) and psychiatric symptom severity (depression, anxiety, fatigue, and pain) in patients before, during and after interferon-alpha based therapy (IFN) for chronic hepatitis C virus infection (HCV). Methods 33 HCV+ adults were evaluated two months before IFN initiation (baseline), three months into IFN, and six months following IFN termination (IFN+ Group). 31 HCV+ adults who did not undergo IFN therapy were evaluated at baseline and six months later (IFN− Group). At each evaluation, participants completed the Neuropsychological Assessment Battery (NAB) Attention, Memory and Executive Functions Modules, the Beck Depression Inventory, Second Edition (BDI), Generalized Anxiety Disorder Inventory (GADI), Fatigue Severity Scale (FSS), and Brief Pain Inventory (BPI). Results Compared with the IFN−Group, the IFN+ Group experienced significantly (p < 0.050) increased symptoms of depression, anxiety, fatigue and pain during IFN therapy relative to baseline. In the IFN+ Group, psychiatric symptoms generally returned to baseline levels following IFN termination. Sustained viral response was associated with significantly lower depression and fatigue. No significant changes in cognitive performance were observed. Conclusions During IFN, patients with HCV evidence significantly increased psychiatric symptoms, including symptoms of depression, anxiety, fatigue and pain. These psychiatric symptoms are generally short-term and remit following IFN termination, with increased benefit if viral clearance is achieved. However, IFN is not associated with significant declines in objective cognitive performance during or following IFN. PMID:25219976

Effect of dietary γ-aminobutyric acid on laying performance, egg quality, immune activity and endocrine hormone in heat-stressed Roman hens.

PubMed

Zhang, Min; Zou, Xiao-Ting; Li, Hui; Dong, Xin-Yang; Zhao, Wenjing

2012-02-01

This study was conducted to evaluate the effect of γ-aminobutyric acid (GABA) on laying performance, egg quality, digestive enzyme activity, hormone level and immune activities in Roman hens under heat stress. Roman hens (320 days old) were fed with 0, 25, 50, 75 and 100 mg/kg GABA, respectively during a 60-day experiment. Compared with control, supplementation of 50 mg/kg GABA improved the laying performance and egg quality by significantly increasing egg production, average egg weight and shell strength (P < 0.05), while decreasing the feed-egg ratio and cholesterol level. Anti-oxidation activity was improved by significantly increasing the activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), but decreasing malondialdehyde level in serum (P < 0.05), while significantly increasing the glucose and total protein (TP) level, follicle stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E(2) ), insulin, triiodothyronine (T(3) ) and free triiodothyronine (FT(3) ) levels, and IgG, IgA and complement (C3)activity in serum (P < 0.05). The results indicated that oral GABA improved laying performance and physical condition mainly by modulating hormone secretion, enhancing anti-oxidation and immune activity, and maintaining electrolyte balance. Fifty mg/kg was the optimum level for laying hens under heat stress in the present study. © 2011 The Authors. Animal Science Journal © 2011 Japanese Society of Animal Science.

Customized mandibular reconstruction plates improve mechanical performance in a mandibular reconstruction model

PubMed Central

Gutwald, Ralf; Jaeger, Raimund; Lambers, Floor M.

2017-01-01

Abstract The purpose of this paper was to analyze the biomechanical performance of customized mandibular reconstruction plates with optimized strength. The best locations for increasing bar widths were determined with a sensitivity analysis. Standard and customized plates were mounted on mandible models and mechanically tested. Maximum stress in the plate could be reduced from 573 to 393 MPa (−31%) by increasing bar widths. The median fatigue limit was significantly greater (p < 0.001) for customized plates (650 ± 27 N) than for standard plates (475 ± 27 N). Increasing bar widths at case-specific locations was an effective strategy for increasing plate fatigue performance. PMID:27887036

Effects of elastic bands on force and power characteristics during the back squat exercise.

PubMed

Wallace, Brian J; Winchester, Jason B; McGuigan, Michael R

2006-05-01

Athletes commonly use elastic bands as a training method to increase strength and performance. The purpose of this study was to investigate the effect of elastic bands on peak force (PF), peak power (PP), and peak rate of force development (RFD) during the back-squat exercise (BSE). Ten recreationally resistance-trained subjects (4 women, 6 men, mean age 21.3 +/- 1.5 years) were tested for their 1 repetition maximum (1RM) in the BSE (mean 117.6 +/- 48.2 kg) on a Smith machine. Testing was performed on 2 separate days, with 2 sets of 3 repetitions being performed for each condition. Testing was conducted at 60% and 85% of 1RM with and without using elastic bands. In addition, 2 elastic band loading conditions were tested (B1 and B2) at each of the 2 resistances. No bands (NB) represents where all of the resistance was acquired from free-weights. B1 represents where approximately 80% of the resistance was provided by free-weights, and approximately 20% was provided by bands. B2 represents where approximately 65% of the resistance was provided by free-weights, and approximately 35% was provided from bands. The subjects completed the BSE under each condition, whereas PF, PP, and RFD was recorded using a force platform. There was a significant (p < 0.05) increase in PF between NB-85 and B2-85 of 16%. Between B1-85 and B2-85, PF was increased significantly by 5% (p < 0.05). There was a significant (p < 0.05) increase in PP between NB-85 and B2-85 of 24%. No significant differences were observed in RFD during the 85% conditions or for any of the measured variables during the 60% conditions (p < 0.05). The results suggest that the use of elastic bands in conjunction with free weights can significantly increase PF and PP during the BSE over free-weight resistance alone under certain loading conditions. The greatest differences are observed during the higher loading conditions, with the B1-85 condition appearing to be optimal for athletic performance of the ones we tested. The strength training professional could use variable resistance training (VRT) to increase PF and PP more than the traditional BSE can. VRT could also be used to train these 2 performance characteristics together, which might be especially useful in season, when weight-room training volume can sometimes be limited.

Biomechanical differences between unilateral and bilateral landings from a jump: gender differences.

PubMed

Pappas, Evangelos; Hagins, Marshall; Sheikhzadeh, Ali; Nordin, Margareta; Rose, Donald

2007-07-01

To determine the effect of landing type (unilateral vs. bilateral) and gender on the biomechanics of drop landings in recreational athletes. This study used a repeated measures design to compare bilateral and unilateral landings in male and female athletes. A repeated measures multivariate analysis of variance (type of landing*gender) was performed on select variables. Biomechanics laboratory. Sixteen female and 16 male recreational athletes. Kinetic, kinematic, and electromyographic (EMG) data were collected on participants while performing bilateral and unilateral landings from a 40-cm platform. Compared to bilateral landings, subjects performed unilateral landings with increased knee valgus, decreased knee flexion at initial contact, decreased peak knee flexion, decreased relative hip adduction, and increased normalized EMG of the rectus femoris, medial hamstrings, lateral hamstrings, and medial gastrocnemius (P < 0.005). During both types of landing, females landed with increased knee valgus and normalized vertical ground reaction force (VGRF) compared to males (P < 0.009), however, the interaction of landing type*gender was not significant (P = 0.29). Compared to bilateral landings, male and female recreational athletes performed unilateral landings with significant differences in knee kinematic and EMG variables. Female athletes landed with increased knee valgus and VGRF compared to males during both types of landing.

Studies on the effects of aspartame on memory and oxidative stress in brain of mice.

PubMed

Abdel-Salam, O M E; Salem, N A; El-Shamarka, M E S; Hussein, J S; Ahmed, N A S; El-Nagar, M E S

2012-12-01

The dipeptide aspartame (N-L-alpha-aspartyl-Lphenylalanine, 1-methyl ester; alpha-APM) is one of the most widely used artificial sweeteners. The present study aimed to investigate the effect of repeated administration of aspartame in the working memory version of Morris water maze test, on oxidative stress and brain monoamines in brain of mice. Aspartame (0.625, 1.875 or 5.625 mg/kg) was administered once daily subcutaneously for 2 weeks and mice were examined four times a week for their ability to locate a submerged plate. Malondialdehyde (MDA), reduced glutathione (GSH), nitric oxide levels (the concentrations of nitrite/nitrate) and glucose were determined in brain. Only at the highest dose of 5.625 mg/kg, did aspartame significantly impaired water maze performance. The mean time taken to find the escape platform (latency) over 2 weeks was significantly delayed by aspartame 5.625 mg/kg, compared with the saline-treated control group. Significant differences occurred only on the first trial to find the escape platform. Significant increase in brain MDA by 16.5% and nitric oxide by 16.2% and a decrease in GSH by 25.1% and glucose by 22.5% occurred after treatment with aspartame at 1.875 mg/kg. Aspartame administered at 5.625 mg/kg significantly increased brain MDA by 43.8%, nitric oxide by 18.6% and decreased GSH by 32.7% and glucose by 25.8%. Aspartame caused dose-dependent inhibition of brain serotonin, noradrenaline and dopamine. These findings suggest impaired memory performance and increased brain oxidative stress by repeated aspartame administration. The impaired memory performance is likely to involve increased oxidative stress as well as decreased brain glucose availability.

Potential ergogenic activity of grape juice in runners.

PubMed

Toscano, Lydiane Tavares; Tavares, Renata Leite; Toscano, Luciana Tavares; Silva, Cássia Surama Oliveira da; Almeida, Antônio Eduardo Monteiro de; Biasoto, Aline Camarão Telles; Gonçalves, Maria da Conceição Rodrigues; Silva, Alexandre Sérgio

2015-09-01

Recent studies have indicated that certain food products have ergogenic potential similar to that of sports supplements. The present study aimed to investigate the potential ergogenic effect of integral purple grape juice on the performance of recreational runners. Twenty-eight volunteers of both sexes (age, 39.8 ± 8.5 years; peak oxygen consumption, 43.2 ± 8.5 mL/(kg·min)) were randomized into either a group that received grape juice (grape juice group (GJG), n = 15; 10 mL/(kg·min) for 28 days) or a group that received an isocaloric, isoglycemic, and isovolumetric control beverage (control group (CG), n = 13). A time-to-exhaustion exercise test, anaerobic threshold test, and aerobic capacity test were performed, together with assessments of markers of oxidative stress, inflammation, immune response, and muscle injury, performed at baseline and 48 h after the supplementation protocol. The GJG showed a significant increase (15.3%) in running time-to-exhaustion (p = 0.002) without significant improvements in either anaerobic threshold (3.6%; p = 0.511) or aerobic capacity (2.2%; p = 0.605). In addition, GJG exhibited significant increases in total antioxidant capacity (38.7%; p = 0.009), vitamin A (11.8%; p = 0.016), and uric acid (28.2%; p = 0.005), whereas α-1-acid glycoprotein significantly decreased (20.2%; p = 0.006) and high-sensitivity C-reactive protein levels remained unchanged. In contrast, no significant changes occurred in any of these variables in the CG. In conclusion, supplementation with purple grape juice shows an ergogenic effect in recreational runners by promoting increased time-to-exhaustion, accompanied by increased antioxidant activity and a possible reduction in inflammatory markers.

Effects of a Flexibility/Support Intervention on Work Performance: Evidence From the Work, Family, and Health Network.

PubMed

Bray, Jeremy W; Hinde, Jesse M; Kaiser, David J; Mills, Michael J; Karuntzos, Georgia T; Genadek, Katie R; Kelly, Erin L; Kossek, Ellen E; Hurtado, David A

2018-05-01

To estimate the effects of a workplace initiative to reduce work-family conflict on employee performance. A group-randomized multisite controlled experimental study with longitudinal follow-up. An information technology firm. Employees randomized to the intervention (n = 348) and control condition (n = 345). An intervention, "Start. Transform. Achieve. Results." to enhance employees' control over their work time, to increase supervisors' support for this change, and to increase employees' and supervisors' focus on results. We estimated the effect of the intervention on 9 self-reported employee performance measures using a difference-in-differences approach with generalized linear mixed models. Performance measures included actual and expected hours worked, absenteeism, and presenteeism. This study found little evidence that an intervention targeting work-family conflict affected employee performance. The only significant effect of the intervention was an approximately 1-hour reduction in expected work hours. After Bonferroni correction, the intervention effect is marginally insignificant at 6 months and marginally significant at 12 and 18 months. The intervention reduced expected working time by 1 hour per week; effects on most other employee self-reported performance measures were statistically insignificant. When coupled with the other positive wellness and firm outcomes, this intervention may be useful for improving employee perceptions of increased access to personal time or personal wellness without sacrificing performance. The null effects on performance provide countervailing evidence to recent negative press on work-family and flex work initiatives.

An increase of intelligence measured by the WPPSI in China, 1984–2006

PubMed Central

Liu, Jianghong; Yang, Hua; Li, Linda; Chen, Tunong; Lynn, Richard

2017-01-01

Normative data for 5–6 year olds on the Chinese Preschool and Primary Scale of Intelligence (WPPSI) are reported for samples tested in 1984 and 2006. There was a significant increase in Full Scale IQ of 4.53 points over the 22 year period, representing a gain of 2.06 IQ points per decade. There were also significant increases in Verbal IQ of 4.27 points and in Performance IQ of 4.08 points. PMID:29416189

Surveillance Range and Interference Impacts on Self-Separation Performance

NASA Technical Reports Server (NTRS)

Idris, Husni; Consiglio, Maria C.; Wing, David J.

2011-01-01

Self-separation is a concept of flight operations that aims to provide user benefits and increase airspace capacity by transferring traffic separation responsibility from ground-based controllers to the flight crew. Self-separation is enabled by cooperative airborne surveillance, such as that provided by the Automatic Dependent Surveillance-Broadcast (ADSB) system and airborne separation assistance technologies. This paper describes an assessment of the impact of ADS-B system performance on the performance of self-separation as a step towards establishing far-term ADS-B performance requirements. Specifically, the impacts of ADS-B surveillance range and interference limitations were analyzed under different traffic density levels. The analysis was performed using a batch simulation of aircraft performing self-separation assisted by NASA s Autonomous Operations Planner prototype flight-deck tool, in two-dimensional airspace. An aircraft detected conflicts within a look-ahead time of ten minutes and resolved them using strategic closed trajectories or tactical open maneuvers if the time to loss of separation was below a threshold. While a complex interaction was observed between the impacts of surveillance range and interference, as both factors are physically coupled, self-separation performance followed expected trends. An increase in surveillance range resulted in a decrease in the number of conflict detections, an increase in the average conflict detection lead time, and an increase in the percentage of conflict resolutions that were strategic. The majority of the benefit was observed when surveillance range was increased to a value corresponding to the conflict detection look-ahead time. The benefits were attenuated at higher interference levels. Increase in traffic density resulted in a significant increase in the number of conflict detections, as expected, but had no effect on the conflict detection lead time and the percentage of conflict resolutions that were strategic. With surveillance range corresponding to ADS-B minimum operational performance standards for Class A3 equipment and without background interference, a significant portion of conflict resolutions, 97 percent, were achieved in the preferred strategic mode. The majority of conflict resolutions, 71 percent, were strategic even with very high interference (over three times that expected in 2035).

The Effects of Cold Whirlpool on Power, Speed, Agility, and Range of Motion

PubMed Central

Patterson, Stephen M.; Udermann, Brian E.; Doberstein, Scott T.; Reineke, David M.

2008-01-01

The purpose was to determine if cold whirlpool treatment decreases functional performance equally regardless of gender. A secondary aim was to determine if there is a gradual increase in functional performance across time. Twenty-one college-aged subjects volunteered to participate in this study and were required to perform four measures of functional performance including: counter movement vertical jump, T-test, 36.58-meter dash (40-yard), and active range of motion of the ankle. Participants were treated with a 20 minute, 10 degree Celsius cold whirlpool following the pre-test of a given functional performance measure. Participants demonstrated significant decreases in counter movement vertical jump, T-test, and 40-yard dash performance immediately following treatment. Vertical jump performance remained impaired for at least 32 minutes. While both the T-test and 40-yard dash were affected for 7 and 22 minutes post- treatment, respectively. Participants also demonstrated significant decreases in peak power and average power immediately after and for 32 minutes post-treatment. Dorsiflexion was significantly decreased 7 and 12 minutes following treatment. There were no differences for plantar flexion, inversion, or eversion. These data suggest functional performance was affected immediately following and for up to 32 minutes after cold whirlpool treatment. It was also evident that there is a gradual performance increase for each measure of functional performance across time. Therefore, the consequences should be carefully considered before returning athletes to activity following cold whirlpool treatment. Key pointsCryotherapy is a common and highly effective modality in treating acute and chronic athletic injuries.The results indicated that cold whirlpool does have an immediate and subsequent effect on functional performance.Understanding how cold whirlpool adversely affects functional performance allows clinicians to continue using this modality before vigorous athletic activity. PMID:24149907

Structurally tailored graphene nanosheets as lithium ion battery anodes: an insight to yield exceptionally high lithium storage performance

NASA Astrophysics Data System (ADS)

Li, Xifei; Hu, Yuhai; Liu, Jian; Lushington, Andrew; Li, Ruying; Sun, Xueliang

2013-11-01

How to tune graphene nanosheets (GNSs) with various morphologies has been a significant challenge for lithium ion batteries (LIBs). In this study, three types of GNSs with varying size, edge sites, defects and layer numbers have been successfully achieved. It was demonstrated that controlling GNS morphology and microstructure has important effects on its cyclic performance and rate capability in LIBs. Diminished GNS layer number, decreased size, increased edge sites and increased defects in the GNS anode can be highly beneficial to lithium storage and result in increased electrochemical performance. Interestingly, GNSs treated with a hydrothermal approach delivered a high reversible discharge capacity of 1348 mA h g-1. This study demonstrates that the controlled design of high performance GNS anodes is an important concept in LIB applications.How to tune graphene nanosheets (GNSs) with various morphologies has been a significant challenge for lithium ion batteries (LIBs). In this study, three types of GNSs with varying size, edge sites, defects and layer numbers have been successfully achieved. It was demonstrated that controlling GNS morphology and microstructure has important effects on its cyclic performance and rate capability in LIBs. Diminished GNS layer number, decreased size, increased edge sites and increased defects in the GNS anode can be highly beneficial to lithium storage and result in increased electrochemical performance. Interestingly, GNSs treated with a hydrothermal approach delivered a high reversible discharge capacity of 1348 mA h g-1. This study demonstrates that the controlled design of high performance GNS anodes is an important concept in LIB applications. Electronic supplementary information (ESI) available: SEM morphologies of GNS-I-III at low magnification, the TEM image of GNSs hydrothermally treated with urea in a ratio of 1 : 0, XPS survey, and SEM morphology changes of the three GNS anodes at low magnification after 100 charge-discharge cycles. See DOI: 10.1039/c3nr04823c

Isoflavones, calcium, vitamin D and inulin improve quality of life, sexual function, body composition and metabolic parameters in menopausal women: result from a prospective, randomized, placebo-controlled, parallel-group study

PubMed Central

Caruso, Salvatore; Rapisarda, Agnese Maria Chiara; Cianci, Stefano; Cianci, Antonio

2018-01-01

Introduction Menopause results in metabolic changes that contribute to increase risk of cardiovascular diseases: increase in low density lipoprotein (LDL) and triglycerides and decrease in high density lipoprotein (HDL), weight gain are associated with a correspondent increase in incidence of hypertension and diabetes. The aim of this study was to evaluate the effect of a preparation of isoflavones, calcium vitamin D and inulin in menopausal women. Material and methods We performed a prospective, randomized, placebo-controlled, parallel-group study. A total of 50 patients were randomized to receive either oral preparations of isoflavones (40 mg), calcium (500 mg) vitamin D (300 UI) and inulin (3 g) or placebo (control group). Pre- and post-treatment assessment of quality of life and sexual function were performed through Menopause-Specific Quality of Life Questionnaire (MENQOL) and Female Sexual Function Index (FSFI); evaluations of anthropometric indicators, body composition through bioelectrical impedance analyser, lumbar spine and proximal femur T-score and lipid profile were performed. Results After 12 months, a significant reduction in MENQOL vasomotor, physical and sexual domain scores (p < 0.05) and a significant increase in all FSFI domain scores (p < 0.05) were observed in treatment group. Laboratory tests showed significant increase in serum levels of HDL (p < 0.05). No significant changes of lumbar spine and femur neck T-score (p > 0.05) were found in the same group. Conclusions According to our data analysis, isoflavones, calcium, vitamin D and inulin may exert favourable effects on menopausal symptoms and signs. PMID:29725283

Effects of Dietary Supplementation with the Combination of Zeolite and Attapulgite on Growth Performance, Nutrient Digestibility, Secretion of Digestive Enzymes and Intestinal Health in Broiler Chickens

PubMed Central

Zhou, P.; Tan, Y. Q.; Zhang, L.; Zhou, Y. M.; Gao, F.; Zhou, G. H.

2014-01-01

This study was designed to investigate the effects of basal diets supplemented with a clay product consisting of zeolite and attapulgite (ZA) at 1:1 ratio on growth performance, digestibility of feed nutrients, activities of digestive enzymes in small intestine and intestinal health in broiler chickens. In experiment 1, 112 one-day-old male chickens were randomly divided into 2 groups with 8 replicates of 7 chickens each. In experiment 2, 84 one-day-old male chickens were randomly allocated into 2 groups consisting 6 replicates of 7 chickens each. The experimental diets both consisted of a maize-soybean basal control diet supplemented with 0% or 2% ZA. The diets were fed from 1 to 42 days of age. The results showed that ZA supplementation could increase body weight gain (BWG) and feed intake (FI), but had no significant effect on feed conversion ratio. The apparent digestibility values of crude protein and gross energy were significantly increased (p<0.05) by ZA from 14 to 16 d and 35 to 37 d. Dietary ZA treatment significantly increased (p<0.05) the activities of amylase, lipase and trypsin in jejunal digesta and the activities of maltase and sucrase in jejunal mucosa on days 21 and 42. The ZA supplementation also significantly increased (p<0.05) the catalase activity, reduced (p<0.05) the malondialdehyde concentration in the jejunal mucosa. In addition, a decrease of serum diamine oxidase activity and an increase (p<0.05) in concentration of secretory immunoglobulin A in jejunal mucosa were observed in birds treated with ZA on 21 and 42 days. It is concluded that ZA supplementation (2%) could partially improve the growth performance by increasing BWG and FI. This improvement was achieved through increasing the secretion of digestive enzymes, enhancing the digestibilites of nutrients, promoting intestinal health of broiler chickens. PMID:25178375

Numerical prediction of micro-channel LD heat sink operated with antifreeze based on CFD method

NASA Astrophysics Data System (ADS)

Liu, Gang; Liu, Yang; Wang, Chao; Wang, Wentao; Wang, Gang; Tang, Xiaojun

2014-12-01

To theoretically study the feasibility of antifreeze coolants applied as cooling fluids for high power LD heat sink, detailed Computational Fluid Dynamics (CFD) analysis of liquid cooled micro-channels heat sinks is presented. The performance operated with antifreeze coolant (ethylene glycol aqueous solution) compared with pure water are numerical calculated for the heat sinks with the same micro-channels structures. The maximum thermal resistance, total pressure loss (flow resistance), thermal resistance vs. flow-rate, and pressure loss vs. flow-rate etc. characteristics are numerical calculated. The results indicate that the type and temperature of coolants plays an important role on the performance of heat sinks. The whole thermal resistance and pressure loss of heat sinks increase significantly with antifreeze coolants compared with pure water mainly due to its relatively lower thermal conductivity and higher fluid viscosity. The thermal resistance and pressure loss are functions of the flow rate and operation temperature. Increasing of the coolant flow rate can reduce the thermal resistance of heat sinks; meanwhile increase the pressure loss significantly. The thermal resistance tends to a limit with increasing flow rate, while the pressure loss tends to increase exponentially with increasing flow rate. Low operation temperature chiefly increases the pressure loss rather than thermal resistance due to the remarkable increasing of fluid viscosity. The actual working point of the cooling circulation system can be determined on the basis of the pressure drop vs. flow rate curve for the micro-channel heat sink and that for the circulation system. In the same system, if the type or/and temperature of the coolant is changed, the working point is accordingly influenced, that is, working flow rate and pressure is changed simultaneously, due to which the heat sink performance is influenced. According to the numerical simulation results, if ethylene glycol aqueous solution is applied instead of pure water as the coolant under the same or a higher working temperature, the available output of optical power will decrease due to the worse heat sink performance; if applied under a lower working temperature(0 °C, －20 °C), although the heat sink performance become worse, however the temperature difference of heat transfer rises more significantly, the available output of optical power will increase on the contrary.

Three-dimensional motion analysis of the lumbar spine during "free squat" weight lift training.

PubMed

Walsh, James C; Quinlan, John F; Stapleton, Robert; FitzPatrick, David P; McCormack, Damian

2007-06-01

Heavy weight lifting using a squat bar is a commonly used athletic training exercise. Previous in vivo motion studies have concentrated on lifting of everyday objects and not on the vastly increased loads that athletes subject themselves to when performing this exercise. Athletes significantly alter their lumbar spinal motion when performing squat lifting at heavy weights. Controlled laboratory study. Forty-eight athletes (28 men, 20 women) performed 6 lifts at 40% maximum, 4 lifts at 60% maximum, and 2 lifts at 80% maximum. The Zebris 3D motion analysis system was used to measure lumbar spine motion. Exercise was performed as a "free" squat and repeated with a weight lifting support belt. Data obtained were analyzed using SAS. A significant decrease (P < .05) was seen in flexion in all groups studied when lifting at 40% maximum compared with lifting at 60% and 80% of maximum lift. Flexion from calibrated 0 point ranged from 24.7 degrees (40% group) to 6.8 degrees (80% group). A significant increase (P < .05) was seen in extension when lifting at 40% maximum was compared with lifting at 60% and 80% maximum lift. Extension from calibrated 0 point ranged from -1.5 degrees (40% group) to -20.3 degrees (80% group). No statistically significant difference was found between motion seen when exercise was performed as a free squat or when lifting using a support belt in any of the groups studied. Weight lifting using a squat bar causes athletes to significantly hyperextend their lumbar spines at heavier weights. The use of a weight lifting support belt does not significantly alter spinal motion during lifting.

Effect of using a laryngeal tube on the no-flow time in a simulated, single-rescuer, basic life support setting with inexperienced users.

PubMed

Meyer, O; Bucher, M; Schröder, J

2016-03-01

The laryngeal tube (LT) is a recommended alternative to endotracheal intubation during advanced life support (ALS). Its insertion is relatively simple; therefore, it may also serve as an alternative to bag mask ventilation (BMV) for untrained personnel performing basic life support (BLS). Data support the influence of LT on the no-flow time (NFT) compared with BMV during ALS in manikin studies. We performed a manikin study to investigate the effect of using the LT for ventilation instead of BMV on the NFT during BLS in a prospective, randomized, single-rescuer study. All 209 participants were trained in BMV, but were inexperienced in using LT; each participant performed BLS during a 4-min time period. No significant difference in total NFT (LT: mean 81.1 ± 22.7 s; BMV: mean 83.2 ± 13.1 s, p = 0.414) was found; however, significant differences in the later periods of the scenario were identified. While ventilating with the LT, the proportion of chest compressions increased significantly from 67.2 to 73.2%, whereas the proportion of chest compressions increased only marginally when performing BMV. The quality of the chest compressions and the associated ventilation rate did not differ significantly. The mean tidal volume and mean minute volume were significantly lower when performing BMV. The NFT was significantly shorter in the later periods in a single-rescuer, cardiac arrest scenario when using an LT without previous training compared with BMV with previous training. A possible explanation for this result may be the complexity and workload of alternating tasks (e.g., time loss when reclining the head and positioning the mask for each ventilation during BMV).

The effect of yeast (Saccharomyces cerevisiae) on nutrient intake, digestibility and finishing performance of lambs fed a diet based on dried molasses sugar beet-pulp.

PubMed

Payandeh, S; Kafilzadeh, F

2007-12-15

This experiment was conducted to determine the effect of yeast (Saccharomyces cerevisiae, SC47) on finishing performance, digestibility, some blood metabolites and carcass characteristics of male lambs fed a diet based on dried Molasses Sugar Beet-Pulp (MSBP). Eighteen Sanjabi male lambs (20.95 +/- 2.7 kg initial body weight and 3 month of age) were used in a completely randomized design. Animals were assigned to one of the two dietary treatments (with or without yeast). Digestibility and nitrogen balance experiment was carried out using six mature rams on finishing diet with and without yeast. Serum metabolites were determined in samples taken from lambs at the end of finishing period. Dry matter digestibility of finishing diet was significantly increased by yeast addition. However, yeast did not have any significant effect on apparent digestibility of OM, NDF, CP and energy. Nitrogen retention was also not affected by yeast addition. Yeast resulted in a significant increase in the average daily gain, dry matter and organic matter intake. However, feed conversion ratio was not significantly affected by addition of yeast. The concentration of the serum metabolites including glucose, urea, cholesterol, sodium, potassium, calcium, phosphorous and cratinine were not affected significantly by yeast supplementation, but triglyceride concentrations increased significantly when yeast was fed. Addition of yeast to the diet did not have any significant effect on the carcass characteristics. Results of this study suggest that feeding saccharomyces cerevisiae with a diet based on MSBP can improve the performance of fattening lambs without any change in carcass characteristics or cuts.

Effects of dietary stachyose on growth performance, digestive enzyme activities and intestinal morphology of juvenile turbot ( Scophthalmus maximus L)

NASA Astrophysics Data System (ADS)

Hu, Haibin; Zhang, Yanjiao; Mai, Kangsen; Ai, Qinghui; Xu, Wei; Zhang, Wenbing; Li, Yanxian; Liu, Jintao

2015-10-01

A 12-week feeding trial was conducted to evaluate the effects of dietary stachyose on the growth performance, digestive enzymes activities and intestinal structures of juvenile turbot ( Scophthalmus maximus L). Five isonitrogenous (49.58% crude protein) and isolipidic (10.50% crude lipid) diets were formulated to contain 0 (Control), 0.625% (S-0.625), 1.25% (S-1.25), 2.5% (S-2.5) and 5% (S-5) stachyose, respectively. With the increase of stachyose level, the growth performance and feed utilization of turbot, such as the specific growth rate, final mean body weight, weight gain rate and feed efficiency, increased significantly ( P< 0.05) and then stabilized. The feed intake of fish fed S-5 was significantly higher ( P< 0.05) than that of fish in other groups. The activities of trypsin, intestinal caseinolytic, stomach and intestinal amylase were significantly influenced by stachyose ( P<0.05). The highest values of trypsin and intestinal caseinolytic activities were observed in group S-1.25, while the highest activity of stomach amylase and the lowest activity of intestine amylase were observed in group S-5. No lesion or damage was found on the distal intestine structures of fish from all treatments, while the height of simple folds in the distal intestine was significantly increased ( P< 0.05) when 1.25% or 2.5% stachyose was added in the diets. These results indicated that moderate level of stachyose (1.25%) improves the growth performance, feed utilization, digestive enzyme activities and the distal intestine structures of juvenile turbot.

Rapid protein disappearance rates along the small intestine advantage poultry performance and influence the post-enteral availability of amino acids.

PubMed

Truong, Ha H; Chrystal, Peter V; Moss, Amy F; Selle, Peter H; Liu, Sonia Yun

2017-12-01

A foundation diet, an intermediate blend and a summit diet were formulated with different levels of soyabean meal, casein and crystalline amino acids to compare 'slow' and 'rapid' protein diets. The diets were offered to male Ross 308 chicks from 7 to 28 d post-hatch and assessed parameters included growth performance, nutrient utilisation, apparent digestibility coefficients and disappearance rates of starch and protein (N) in four small intestinal segments. Digestibility coefficients and disappearance rates of sixteen amino acids in three small intestinal segments and amino acid concentrations in plasma from portal and systemic circulations from the foundation and summit diets were determined. The dietary transition significantly accelerated protein (N) disappearance rates in the distal jejunum and ileum. The transition from foundation to summit diets significantly increased starch digestibility coefficients in the ileum and disappearance rates in all four small intestinal segments. These starch responses were associated with significant enhancements in nutrient utilisation. The dietary transition linearly increased digestibility coefficients and disappearance rates of amino acids in the majority of cases. The summit diet increased plasma concentrations of five amino acids but decreased those of four amino acids relative to the foundation diet to significant extents. Plasma concentrations of free amino acids were higher in the portal than systemic circulations. Rapid protein disappearance rates advantaged poultry performance and influenced post-enteral availability of amino acids. If the underlying mechanisms are to be identified, further research into the impact of protein digestive dynamics on broiler performance is required but appears justified.

Effect of echo spacing and readout bandwidth on basic performances of EPI-fMRI acquisition sequences implemented on two 1.5 T MR scanner systems.

PubMed

Giannelli, Marco; Diciotti, Stefano; Tessa, Carlo; Mascalchi, Mario

2010-01-01

Although in EPI-fMRI analyses typical acquisition parameters (TR, TE, matrix, slice thickness, etc.) are generally employed, various readout bandwidth (BW) values are used as a function of gradients characteristics of the MR scanner. Echo spacing (ES) is another fundamental parameter of EPI-fMRI acquisition sequences but the employed ES value is not usually reported in fMRI studies. In the present work, the authors investigated the effect of ES and BW on basic performances of EPI-fMRI sequences in terms of temporal stability and overall image quality of time series acquisition. EPI-fMRI acquisitions of the same water phantom were performed using two clinical MR scanner systems (scanners A and B) with different gradient characteristics and functional designs of radiofrequency coils. For both scanners, the employed ES values ranged from 0.75 to 1.33 ms. The used BW values ranged from 125.0 to 250.0 kHz/64pixels and from 78.1 to 185.2 kHz/64pixels for scanners A and B, respectively. The temporal stability of EPI-fMRI sequence was assessed measuring the signal-to-fluctuation noise ratio (SFNR) and signal drift (DR), while the overall image quality was assessed evaluating the signal-to-noise ratio (SNR(ts)) and nonuniformity (NU(ts)) of the time series acquisition. For both scanners, no significant effect of ES and BW on signal drift was revealed. The SFNR, NU(ts) and SNR(ts) values of scanner A did not significantly vary with ES. On the other hand, the SFNR, NU(ts), and SNR(ts) values of scanner B significantly varied with ES. SFNR (5.8%) and SNR(ts) (5.9%) increased with increasing ES. SFNR (25% scanner A, 32% scanner B) and SNR(ts) (26.2% scanner A, 30.1% scanner B) values of both scanners significantly decreased with increasing BW. NU(ts) values of scanners A and B were less than 3% for all BW and ES values. Nonetheless, scanner A was characterized by a significant upward trend (3% percentage of variation) of time series nonuniformity with increasing BW while NU(ts) of scanner B significantly increased (19% percentage of variation) with increasing ES. Temporal stability (SFNR and DR) and overall image quality (NU(ts) and SNR(ts)) of EPI-fMRI time series can significantly vary with echo spacing and readout bandwidth. The specific pattern of variation may depend on the performance of each single MR scanner system in terms of gradients characteristics, EPI sequence calibrations (eddy currents, shimming, etc.), and functional design of radiofrequency coil. Our results indicate that the employment of low BW improves not only the signal-to-noise ratio of EPI-fMRI time series but also the temporal stability of functional acquisitions. The use of minimum ES values is not entirely advantageous when the MR scanner system is characterized by gradients with low performances and suboptimal EPI sequence calibration. Since differences in basic performances of MR scanner system are potential source of variability for fMRI activation, phantom measurements of SFNR, DR, NU(ts), and SNR(ts) can be executed before subjects acquisitions to monitor the stability of MR scanner performances in clinical group comparison and longitudinal studies.

“The 3/3 Strategy”: A Successful Multifaceted Hospital Wide Hand Hygiene Intervention Based on WHO and Continuous Quality Improvement Methodology

PubMed Central

Mestre, Gabriel; Berbel, Cristina; Tortajada, Purificación; Alarcia, Margarita; Coca, Roser; Gallemi, Gema; Garcia, Irene; Fernández, Mari Mar; Aguilar, Mari Carmen; Martínez, José Antonio; Rodríguez-Baño, Jesús

2012-01-01

Background Only multifaceted hospital wide interventions have been successful in achieving sustained improvements in hand hygiene (HH) compliance. Methodology/Principal Findings Pre-post intervention study of HH performance at baseline (October 2007– December 2009) and during intervention, which included two phases. Phase 1 (2010) included multimodal WHO approach. Phase 2 (2011) added Continuous Quality Improvement (CQI) tools and was based on: a) Increase of alcohol hand rub (AHR) solution placement (from 0.57 dispensers/bed to 1.56); b) Increase in frequency of audits (three days every three weeks: “3/3 strategy”); c) Implementation of a standardized register form of HH corrective actions; d) Statistical Process Control (SPC) as time series analysis methodology through appropriate control charts. During the intervention period we performed 819 scheduled direct observation audits which provided data from 11,714 HH opportunities. The most remarkable findings were: a) significant improvements in HH compliance with respect to baseline (25% mean increase); b) sustained high level (82%) of HH compliance during intervention; c) significant increase in AHRs consumption over time; c) significant decrease in the rate of healthcare-acquired MRSA; d) small but significant improvements in HH compliance when comparing phase 2 to phase 1 [79.5% (95% CI: 78.2–80.7) vs 84.6% (95% CI:83.8–85.4), p<0.05]; e) successful use of control charts to identify significant negative and positive deviations (special causes) related to the HH compliance process over time (“positive”: 90.1% as highest HH compliance coinciding with the “World hygiene day”; and “negative”:73.7% as lowest HH compliance coinciding with a statutory lay-off proceeding). Conclusions/Significance CQI tools may be a key addition to WHO strategy to maintain a good HH performance over time. In addition, SPC has shown to be a powerful methodology to detect special causes in HH performance (positive and negative) and to help establishing adequate feedback to healthcare workers. PMID:23110061

Effect of plyometric training on lower limb biomechanics in females.

PubMed

Baldon, Rodrigo de Marche; Moreira Lobato, Daniel F; Yoshimatsu, Andre P; dos Santos, Ana Flávia; Francisco, Andrea L; Pereira Santiago, Paulo R; Serrão, Fábio V

2014-01-01

To verify the effects of plyometric training on lower limb kinematics, eccentric hip and knee torques, and functional performance. Cohort study. Research laboratory. Thirty-six females were divided into a training group (TG; n = 18) that carried out the plyometric training for 8 weeks, and a control group (CG; n = 18) that carried out no physical training. Twenty-four plyometric training sessions during approximately 8 weeks with 3 sessions per week on alternate days. Lower limb kinematics (maximum excursion of hip adduction, hip medial rotation, and knee abduction during the single leg squat), eccentric hip (abductor, adductor, medial, and lateral rotator) isokinetic peak torques and knee (flexor and extensor) isokinetic peak torques, and functional performance (triple hop test and the 6-m timed hop test). After 8 weeks, only the TG significantly reduced the values for the maximum excursion of knee abduction (P = 0.01) and hip adduction (P < 0.001). Similarly, only the TG significantly increased the eccentric hip abductor (P < 0.001) and adductor (P = 0.01) torques. Finally, only the TG significantly increased the values in the triple hop test (P < 0.001) and significantly decreased the values in the 6-m timed hop test (P < 0.001) after intervention. Plyometric training alters lower limb kinematics and increases eccentric hip torque and functional performance, suggesting the incorporation of these exercises in preventive programs for ACL injuries.

Graphene-Based Transparent Electrodes for Dye Sensitized Solar Cells

NASA Astrophysics Data System (ADS)

Al-Rawashdeh, Nathir A. F.; Albiss, Borhan A.; Yousef, Mo'ath H. I.

2018-02-01

Several Zinc Oxide (ZnO) photo-anodes were prepared with different morphologies. For each morphology, two composites containing graphene oxide (GO) were prepared. ZnO sheet-flowers attained the highest efficiency among control samples, owing to the light diffraction that may be caused by such morphology. On the other hand, ZnO rods achieved lower performance than ZnO sheet-flowers, but higher than ZnO flowers, due to their porosity and structure, which may scatter light effectively. The effect of including GO in the photoanode matrix was studied and the results demonstrate a significant increase in short circuit current density (JSC). The addition of GO suggested an overall positive effect on cell performance, where samples of ZnO rods and Flowers had the most significant increase in their performance, due to the inhibition of charge recombination by GO.

Effects of Filtering Visual Short Wavelengths During Nocturnal Shiftwork on Sleep and Performance

PubMed Central

Rahman, Shadab A.; Shapiro, Colin M.; Wang, Flora; Ainlay, Hailey; Kazmi, Syeda; Brown, Theodore J.

2013-01-01

Circadian phase resetting is sensitive to visual short wavelengths (450–480 nm). Selectively filtering this range of wavelengths may reduce circadian misalignment and sleep impairment during irregular light-dark schedules associated with shiftwork. We examined the effects of filtering short wavelengths (<480 nm) during night shifts on sleep and performance in nine nurses (five females and four males; mean age ± SD: 31.3 ± 4.6 yrs). Participants were randomized to receive filtered light (intervention) or standard indoor light (baseline) on night shifts. Nighttime sleep after two night shifts and daytime sleep in between two night shifts was assessed by polysomnography (PSG). In addition, salivary melatonin levels and alertness were assessed every 2 h on the first night shift of each study period and on the middle night of a run of three night shifts in each study period. Sleep and performance under baseline and intervention conditions were compared with daytime performance on the seventh day shift, and nighttime sleep following the seventh daytime shift (comparator). On the baseline night PSG, total sleep time (TST) (p < 0.01) and sleep efficiency (p = 0.01) were significantly decreased and intervening wake times (wake after sleep onset [WASO]) (p = 0.04) were significantly increased in relation to the comparator night sleep. In contrast, under intervention, TST was increased by a mean of 40 min compared with baseline, WASO was reduced and sleep efficiency was increased to levels similar to the comparator night. Daytime sleep was significantly impaired under both baseline and intervention conditions. Salivary melatonin levels were significantly higher on the first (p < 0.05) and middle (p < 0.01) night shifts under intervention compared with baseline. Subjective sleepiness increased throughout the night under both conditions (p < 0.01). However, reaction time and throughput on vigilance tests were similar to daytime performance under intervention but impaired under baseline on the first night shift. By the middle night shift, the difference in performance was no longer significant between day shift and either of the two night shift conditions, suggesting some adaptation to the night shift had occurred under baseline conditions. These results suggest that both daytime and nighttime sleep are adversely affected in rotating-shift workers and that filtering short wavelengths may be an approach to reduce sleep disruption and improve performance in rotating-shift workers. (Author correspondence: casper@lunenfeld.ca) PMID:23834705

The Effects of Creatine Supplementation on Explosive Performance and Optimal Individual Postactivation Potentiation Time.

PubMed

Wang, Chia-Chi; Yang, Ming-Ta; Lu, Kang-Hao; Chan, Kuei-Hui

2016-03-04

Creatine plays an important role in muscle energy metabolism. Postactivation potentiation (PAP) is a phenomenon that can acutely increase muscle power, but it is an individualized process that is influenced by muscle fatigue. This study examined the effects of creatine supplementation on explosive performance and the optimal individual PAP time during a set of complex training bouts. Thirty explosive athletes performed tests of back squat for one repetition maximum (1RM) strength and complex training bouts for determining the individual optimal timing of PAP, height and peak power of a counter movement jump before and after the supplementation. Subjects were assigned to a creatine or placebo group and then consumed 20 g of creatine or carboxymethyl cellulose per day for six days. After the supplementation, the 1RM strength in the creatine group significantly increased (p < 0.05). The optimal individual PAP time in the creatine group was also significant earlier than the pre-supplementation and post-supplementation of the placebo group (p < 0.05). There was no significant difference in jump performance between the groups. This study demonstrates that creatine supplementation improves maximal muscle strength and the optimal individual PAP time of complex training but has no effect on explosive performance.

The Effects of Creatine Supplementation on Explosive Performance and Optimal Individual Postactivation Potentiation Time

PubMed Central

Wang, Chia-Chi; Yang, Ming-Ta; Lu, Kang-Hao; Chan, Kuei-Hui

2016-01-01

Creatine plays an important role in muscle energy metabolism. Postactivation potentiation (PAP) is a phenomenon that can acutely increase muscle power, but it is an individualized process that is influenced by muscle fatigue. This study examined the effects of creatine supplementation on explosive performance and the optimal individual PAP time during a set of complex training bouts. Thirty explosive athletes performed tests of back squat for one repetition maximum (1RM) strength and complex training bouts for determining the individual optimal timing of PAP, height and peak power of a counter movement jump before and after the supplementation. Subjects were assigned to a creatine or placebo group and then consumed 20 g of creatine or carboxymethyl cellulose per day for six days. After the supplementation, the 1RM strength in the creatine group significantly increased (p < 0.05). The optimal individual PAP time in the creatine group was also significant earlier than the pre-supplementation and post-supplementation of the placebo group (p < 0.05). There was no significant difference in jump performance between the groups. This study demonstrates that creatine supplementation improves maximal muscle strength and the optimal individual PAP time of complex training but has no effect on explosive performance. PMID:26959056

Biometric identification: a holistic perspective

NASA Astrophysics Data System (ADS)

Nadel, Lawrence D.

2007-04-01

Significant advances continue to be made in biometric technology. However, the global war on terrorism and our increasingly electronic society have created the societal need for large-scale, interoperable biometric capabilities that challenge the capabilities of current off-the-shelf technology. At the same time, there are concerns that large-scale implementation of biometrics will infringe our civil liberties and offer increased opportunities for identity theft. This paper looks beyond the basic science and engineering of biometric sensors and fundamental matching algorithms and offers approaches for achieving greater performance and acceptability of applications enabled with currently available biometric technologies. The discussion focuses on three primary biometric system aspects: performance and scalability, interoperability, and cost benefit. Significant improvements in system performance and scalability can be achieved through careful consideration of the following elements: biometric data quality, human factors, operational environment, workflow, multibiometric fusion, and integrated performance modeling. Application interoperability hinges upon some of the factors noted above as well as adherence to interface, data, and performance standards. However, there are times when the price of conforming to such standards can be decreased local system performance. The development of biometric performance-based cost benefit models can help determine realistic requirements and acceptable designs.

Non-starch polysaccharide-degrading enzymes increase the performance of broiler chickens fed wheat of low apparent metabolizable energy.

PubMed

Choct, M; Hughes, R J; Trimble, R P; Angkanaporn, K; Annison, G

1995-03-01

The effect of a commercial glycanase product (Avizyme TX) on the performance of 4-wk-old broiler chickens fed wheats with low and normal apparent metabolizable energy values was studied. Controls were fed a corn-based diet. Supplementation with the enzyme product significantly (P < 0.01) increased the apparent metabolizable energy of the low metabolizable energy wheat from 12.02 to 14.94 MJ/kg dry matter. The apparent metabolizable energy value of the normal wheat was increased from 14.52 to 14.83 MJ/kg dry matter; this was, however, not significant. Birds fed the low metabolizable energy wheat diet had significantly (P < 0.01) higher digesta viscosity and lower small intestinal starch and protein digestibilities than birds fed the normal wheat diet. Chickens fed the low metabolizable energy wheat tended to grow less than those fed the normal wheat diet. When the low metabolizable energy wheat+enzyme diet was fed, digesta viscosity was significantly (P < 0.01) lower (20.28 vs. 10.36 mPa.s), and small intestinal digestibility coefficient of starch was significantly (P < 0.01) greater (0.584 vs. 0.861) relative to values in birds fed the low metabolizable energy wheat diet alone. Although the protein digestibility coefficient also increased from 0.689 to 0.745, the difference was not significant. Weight gain and feed efficiency of birds fed the low metabolizable energy wheat+enzyme equaled those of controls. The enzyme product significantly (P < 0.01) increased the solubilization of non-starch polysaccharides within the gastrointestinal tract of birds fed both types of wheat diets.(ABSTRACT TRUNCATED AT 250 WORDS)

Differences in regulatory T-cell and dendritic cell pattern in decidual tissue of placenta accreta/increta cases.

PubMed

Schwede, S; Alfer, J; von Rango, U

2014-06-01

Primary infertility, miscarriage, and preeclampsia have been correlated with reduced numbers of regulatory T-cells (Treg) suggesting that decreased extravillous trophoblast (EVT) invasion originates from inadequate EVT tolerance. In contrast increased numbers of Treg-cells may be responsible for over-invasion of EVT. As the maturation status of dendritic cells (DC) influences T-cell behavior (tolerance or immune activation), altered relation between immature and mature DCs may also influence EVT invasion. Paraffin-embedded specimens of placenta accreta/increta (Pc; n = 11) and healthy intrauterine pregnancy (IUG; n = 18) were double-stained for cytokeratin and CD45, CD68, CD56, CD20, CD3, or CD8 as well as FoxP3/CD4 and FoxP3/CD8 and single-stained for CD4, CD25, FoxP3, CD209, Dec205 and CD83. Quantification of the leukocyte subpopulations was performed for decidua parietalis and basalis as characterized by cytokeratin-positive EVT. Statistical analysis was performed by using the Mann-Whitney test. There were significantly fewer CD4(+) cells in Pc than in IUG. Concerning the Treg-markers, FoxP3(+) cells are significantly increased. CD25(+) cells showed a small non-significant increase in Pc in comparison to IUG. Concerning dendritic cells, immature non-activated CD209(+) DCs were significantly decreased in Pc while immature activated CD205(+) DCs were slightly but non-significantly increased. Mature activated CD83(+) DC were non-significantly decreased in IUG vs Pc. The increased number of Treg-cells in Pc suggests significance for these cells in the regulation of trophoblast invasion. Their adequate interaction with other lymphocyte populations (e.g. adequately maturated dendritic cells) may be one mechanism to assure controlled EVT invasion. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effects of a Modified German Volume Training Program on Muscular Hypertrophy and Strength.

PubMed

Amirthalingam, Theban; Mavros, Yorgi; Wilson, Guy C; Clarke, Jillian L; Mitchell, Lachlan; Hackett, Daniel A

2017-11-01

Amirthalingam, T, Mavros, Y, Wilson, GC, Clarke, JL, Mitchell, L, and Hackett, DA. Effects of a modified German volume training program on muscular hypertrophy and strength. J Strength Cond Res 31(11): 3109-3119, 2017-German Volume Training (GVT), or the 10 sets method, has been used for decades by weightlifters to increase muscle mass. To date, no study has directly examined the training adaptations after GVT. The purpose of this study was to investigate the effect of a modified GVT intervention on muscular hypertrophy and strength. Nineteen healthy men were randomly assign to 6 weeks of 10 or 5 sets of 10 repetitions for specific compound resistance exercises included in a split routine performed 3 times per week. Total and regional lean body mass, muscle thickness, and muscle strength were measured before and after the training program. Across groups, there were significant increases in lean body mass measures, however, greater increases in trunk (p = 0.043; effect size [ES] = -0.21) and arm (p = 0.083; ES = -0.25) lean body mass favored the 5-SET group. No significant increases were found for leg lean body mass or measures of muscle thickness across groups. Significant increases were found across groups for muscular strength, with greater increases in the 5-SET group for bench press (p = 0.014; ES = -0.43) and lat pull-down (p = 0.003; ES = -0.54). It seems that the modified GVT program is no more effective than performing 5 sets per exercise for increasing muscle hypertrophy and strength. To maximize hypertrophic training effects, it is recommended that 4-6 sets per exercise be performed, as it seems gains will plateau beyond this set range and may even regress due to overtraining.

Leaf Morphology, Photosynthetic Performance, Chlorophyll Fluorescence, Stomatal Development of Lettuce (Lactuca sativa L.) Exposed to Different Ratios of Red Light to Blue Light.

PubMed

Wang, Jun; Lu, Wei; Tong, Yuxin; Yang, Qichang

2016-01-01

Red and blue light are both vital factors for plant growth and development. We examined how different ratios of red light to blue light (R/B) provided by light-emitting diodes affected photosynthetic performance by investigating parameters related to photosynthesis, including leaf morphology, photosynthetic rate, chlorophyll fluorescence, stomatal development, light response curve, and nitrogen content. In this study, lettuce plants (Lactuca sativa L.) were exposed to 200 μmol⋅m(-2)⋅s(-1) irradiance for a 16 h⋅d(-1) photoperiod under the following six treatments: monochromatic red light (R), monochromatic blue light (B) and the mixture of R and B with different R/B ratios of 12, 8, 4, and 1. Leaf photosynthetic capacity (A max) and photosynthetic rate (P n) increased with decreasing R/B ratio until 1, associated with increased stomatal conductance, along with significant increase in stomatal density and slight decrease in stomatal size. P n and A max under B treatment had 7.6 and 11.8% reduction in comparison with those under R/B = 1 treatment, respectively. The effective quantum yield of PSII and the efficiency of excitation captured by open PSII center were also significantly lower under B treatment than those under the other treatments. However, shoot dry weight increased with increasing R/B ratio with the greatest value under R/B = 12 treatment. The increase of shoot dry weight was mainly caused by increasing leaf area and leaf number, but no significant difference was observed between R and R/B = 12 treatments. Based on the above results, we conclude that quantitative B could promote photosynthetic performance or growth by stimulating morphological and physiological responses, yet there was no positive correlation between P n and shoot dry weight accumulation.

Leaf Morphology, Photosynthetic Performance, Chlorophyll Fluorescence, Stomatal Development of Lettuce (Lactuca sativa L.) Exposed to Different Ratios of Red Light to Blue Light

PubMed Central

Wang, Jun; Lu, Wei; Tong, Yuxin; Yang, Qichang

2016-01-01

Red and blue light are both vital factors for plant growth and development. We examined how different ratios of red light to blue light (R/B) provided by light-emitting diodes affected photosynthetic performance by investigating parameters related to photosynthesis, including leaf morphology, photosynthetic rate, chlorophyll fluorescence, stomatal development, light response curve, and nitrogen content. In this study, lettuce plants (Lactuca sativa L.) were exposed to 200 μmol⋅m−2⋅s−1 irradiance for a 16 h⋅d−1 photoperiod under the following six treatments: monochromatic red light (R), monochromatic blue light (B) and the mixture of R and B with different R/B ratios of 12, 8, 4, and 1. Leaf photosynthetic capacity (Amax) and photosynthetic rate (Pn) increased with decreasing R/B ratio until 1, associated with increased stomatal conductance, along with significant increase in stomatal density and slight decrease in stomatal size. Pn and Amax under B treatment had 7.6 and 11.8% reduction in comparison with those under R/B = 1 treatment, respectively. The effective quantum yield of PSII and the efficiency of excitation captured by open PSII center were also significantly lower under B treatment than those under the other treatments. However, shoot dry weight increased with increasing R/B ratio with the greatest value under R/B = 12 treatment. The increase of shoot dry weight was mainly caused by increasing leaf area and leaf number, but no significant difference was observed between R and R/B = 12 treatments. Based on the above results, we conclude that quantitative B could promote photosynthetic performance or growth by stimulating morphological and physiological responses, yet there was no positive correlation between Pn and shoot dry weight accumulation. PMID:27014285

Utilization of apical vaginal support procedures at time of inpatient hysterectomy performed for benign conditions: a national estimate.

PubMed

Ross, Whitney Trotter; Meister, Melanie R; Shepherd, Jonathan P; Olsen, Margaret A; Lowder, Jerry L

2017-10-01

Apical vaginal support is considered the keystone of pelvic organ support. Level I evidence supports reestablishment of apical support at time of hysterectomy, regardless of whether the hysterectomy is performed for prolapse. National rates of apical support procedure performance at time of inpatient hysterectomy have not been well described. We sought to estimate trends and factors associated with use of apical support procedures at time of inpatient hysterectomy for benign indications in a large national database. The National (Nationwide) Inpatient Sample was used to identify hysterectomies performed from 2004 through 2013 for benign indications. International Classification of Diseases, Ninth Revision, Clinical Modification codes were used to select both procedures and diagnoses. The primary outcome was performance of an apical support procedure at time of hysterectomy. Descriptive and multivariable analyses were performed. There were 3,509,230 inpatient hysterectomies performed for benign disease from 2004 through 2013. In both nonprolapse and prolapse groups, there was a significant decrease in total number of annual hysterectomies performed over the study period (P < .0001). There were 2,790,652 (79.5%) hysterectomies performed without a diagnosis of prolapse, and an apical support procedure was performed in only 85,879 (3.1%). There was a significant decrease in the proportion of hysterectomies with concurrent apical support procedure (high of 4.0% in 2004 to 2.5% in 2013, P < .0001). In the multivariable logistic regression model, increasing age, hospital type (urban teaching), hospital bed size (large and medium), and hysterectomy type (vaginal and laparoscopically assisted vaginal) were associated with performance of an apical support procedure. During the study period, 718,578 (20.5%) inpatient hysterectomies were performed for prolapse diagnoses and 266,743 (37.1%) included an apical support procedure. There was a significant increase in the proportion of hysterectomies with concurrent apical support procedure (low of 31.3% in 2005 to 49.3% in 2013, P < .0001). In the multivariable logistic regression model, increasing age, hospital type (urban teaching), hospital bed size (medium and large), and hysterectomy type (total laparoscopic and laparoscopic supracervical) were associated with performance of an apical support procedure. This national database study demonstrates that apical support procedures are not routinely performed at time of inpatient hysterectomy regardless of presence of prolapse diagnosis. Educational efforts are needed to increase awareness of the importance of reestablishing apical vaginal support at time of hysterectomy regardless of indication. Copyright © 2017 Elsevier Inc. All rights reserved.

Deep learning for hybrid EEG-fNIRS brain-computer interface: application to motor imagery classification.

PubMed

Chiarelli, Antonio Maria; Croce, Pierpaolo; Merla, Arcangelo; Zappasodi, Filippo

2018-06-01

Brain-computer interface (BCI) refers to procedures that link the central nervous system to a device. BCI was historically performed using electroencephalography (EEG). In the last years, encouraging results were obtained by combining EEG with other neuroimaging technologies, such as functional near infrared spectroscopy (fNIRS). A crucial step of BCI is brain state classification from recorded signal features. Deep artificial neural networks (DNNs) recently reached unprecedented complex classification outcomes. These performances were achieved through increased computational power, efficient learning algorithms, valuable activation functions, and restricted or back-fed neurons connections. By expecting significant overall BCI performances, we investigated the capabilities of combining EEG and fNIRS recordings with state-of-the-art deep learning procedures. We performed a guided left and right hand motor imagery task on 15 subjects with a fixed classification response time of 1 s and overall experiment length of 10 min. Left versus right classification accuracy of a DNN in the multi-modal recording modality was estimated and it was compared to standalone EEG and fNIRS and other classifiers. At a group level we obtained significant increase in performance when considering multi-modal recordings and DNN classifier with synergistic effect. BCI performances can be significantly improved by employing multi-modal recordings that provide electrical and hemodynamic brain activity information, in combination with advanced non-linear deep learning classification procedures.

Effects of noise and mental task performance upon changes in cerebral blood flow parameters

PubMed Central

Nowakowska-Kotas, Marta; Pokryszko-Dragan, Anna; Brodowski, Mirosław; Szydło, Mariusz; Podemski, Ryszard

2015-01-01

The objectives of this paper were to determine whether traffic noise influences the parameters of cerebral blood flow (CBF) measured by functional transcranial Doppler sonography (fTCD) during the performance of mental tasks, and to see whether impact of noise on CBF changes with age. The study comprised 36 healthy volunteers, 22 women and 14 men, aged 25-49 years. The fTCD was performed using a fixed 2-MHz probe, aiming for an evaluation of mean velocity (MFV) and the pulsatility index (PI) in the middle cerebral artery (MCA) on both sides. Subsequently, fTCD was monitored: At rest; during performance of the Paced Auditory Serial Addition Test (PASAT); during exposure to traffic noise; and during concomitant exposure to noise and PASAT performance. MFV and PI were compared for particular conditions and correlated with age. During exposure to noise, flow parameters did not change significantly. PASAT performance in silence increased MFV and decreased PI in MCA on both sides. During PASAT performance, on exposure to noise, MCV and PI changed significantly only in the left MCA. However, values of MFV were significantly lower during noise than in silence. Correlations with age were noted for velocities in the right MCA during PASAT performance in silence and for PI on both sides during PASAT performed in noise conditions. Noise impairs the CBF during mental tasks. A comparison of changes in CBF parameters correlated with age suggests that the involvement of the nondominant hemisphere in managing with noise effects increases with age. PMID:26572702

Increasing Flexibility in Energy Code Compliance: Performance Packages

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hart, Philip R.; Rosenberg, Michael I.

Energy codes and standards have provided significant increases in building efficiency over the last 38 years, since the first national energy code was published in late 1975. The most commonly used path in energy codes, the prescriptive path, appears to be reaching a point of diminishing returns. As the code matures, the prescriptive path becomes more complicated, and also more restrictive. It is likely that an approach that considers the building as an integrated system will be necessary to achieve the next real gains in building efficiency. Performance code paths are increasing in popularity; however, there remains a significant designmore » team overhead in following the performance path, especially for smaller buildings. This paper focuses on development of one alternative format, prescriptive packages. A method to develop building-specific prescriptive packages is reviewed based on a multiple runs of prototypical building models that are used to develop parametric decision analysis to determines a set of packages with equivalent energy performance. The approach is designed to be cost-effective and flexible for the design team while achieving a desired level of energy efficiency performance. A demonstration of the approach based on mid-sized office buildings with two HVAC system types is shown along with a discussion of potential applicability in the energy code process.« less

Neuromuscular adaptations to 4 weeks of intensive drop jump training in well-trained athletes

PubMed Central

Alkjaer, Tine; Meyland, Jacob; Raffalt, Peter C; Lundbye-Jensen, Jesper; Simonsen, Erik B

2013-01-01

This study examined the effects of 4 weeks of intensive drop jump training in well-trained athletes on jumping performance and underlying changes in biomechanics and neuromuscular adaptations. Nine well-trained athletes at high national competition level within sprinting and jumping disciplines participated in the study. The training was supervised and augmented feedback on performance was used to ensure maximal training intensity. The drop jumps were performed with minimal contact time and maximal jumping height. Assessment of performance during training showed effects of motor learning. Before and after the training intervention maximal isometric muscle strength, the biomechanics, muscle activity pattern of the lower extremities and the soleus H-reflex and V-wave during drop jumping were measured. Maximal jump height and performance index (PI) defined as jumping height divided by contact time improved significantly by 11.9% (P = 0.024) and 16.2% (P = 0.009), respectively. Combined ankle and knee joint peak power was significantly increased by 7% after training (P = 0.047). The preactivity in the soleus muscle decreased 16% (P = 0.015). The soleus H-reflex was unchanged after training, while the soleus V-wave increased significantly at 45 msec after touchdown. This may indicate an increased drive to the α-motor neuron pool following training. Muscle strength parameters were unaffected by the training. The results demonstrate that 4 weeks of intensive drop jump training can improve jumping performance also in well-trained athletes without concomitant changes in muscle strength. It is suggested that the behavioral improvement is primarily due to neural factors regulating the activation pattern controlling the drop jump movement. PMID:24303171

The effect of l-arginine supplementation on body composition and performance in male athletes: a double-blinded randomized clinical trial.

PubMed

Pahlavani, N; Entezari, M H; Nasiri, M; Miri, A; Rezaie, M; Bagheri-Bidakhavidi, M; Sadeghi, O

2017-04-01

Athletes used a lot of dietary supplements to achieve the more muscle mass and improve their athletic performance. The objective of this study was to investigate the effect of l-arginine supplementation on sport performance and body composition in male soccer players. This double-blinded, randomized and placebo-controlled trial was conducted on 56 male soccer players, with age range of 16-35, who referred to sport clubs in Isfahan, Iran. Subjects were randomly assigned to either l-arginine or placebo groups. Athletes received daily either 2 g per day l-arginine supplement or the same amount of placebo (maltodextrin) for 45 days. Sport performance and also body mass index (BMI), body fat mass (BFM) and lean body mass (LBM) were measured at the beginning and end of the study. Also, 3-day dietary records were collected at three different time points (before, in the middle of, and at the end of the study). The mean age of subjects was 20.85±4.29 years. Sport performance (VO 2 max) significantly increased in l-arginine supplementation group (4.12±6.07) compared with placebo group (1.23±3.36) (P=0.03). This increase remained significant even after adjustment of baseline values, physical activity and usual dietary intake of subjects throughout the study. No significant effect of l-arginine supplementation was found on weight, BMI, BFM and LBM. l-arginine supplementation (2 g per day) could increase the sport performance in male athletes, but had no effect on anthropometric measurements, including BMI, BFM and LBM. So, further studies are needed to shed light our findings.

Thermal physiology of the fingered limpet Lottia digitalis under emersion and immersion.

PubMed

Bjelde, Brittany E; Todgham, Anne E

2013-08-01

Marine animals living high in the rocky intertidal zone experience long durations of aerial emersion, sometimes enduring rapid increases in temperature. To date, much of our understanding of the thermal physiology of intertidal organisms comes from studies in which organisms are exposed to increasing temperatures when immersed, with the added effect of aerial emersion rarely considered. In this study, we examined the physiological response of the finger limpet, Lottia digitalis, to increases in temperature under both immersed and emersed conditions. We investigated the thermal sensitivity and upper temperature tolerance of limpets through assessment of cardiac performance, metabolic rate, glycogen depletion and maintenance of protein integrity. Cardiac performance in response to ecologically relevant increases in temperature was similar in emersed and immersed limpets from 15 to 35°C and showed multiple break patterns in heart rate as temperature was increased. Overall, emersed limpets had a greater upper thermal limit on cardiac performance, with the ability to maintain heart rate at a temperature 3-5°C higher than that for immersed limpets. Metabolism in limpets also differed significantly between emersion and immersion, where a significant depression in aerobic metabolic rate was observed under immersion with increasing temperature. Greater levels of ubiquitin-conjugated proteins were found under emersed conditions compared with immersed limpets. Maintaining cardiac performance and aerobic metabolism to higher temperatures under emersed conditions is likely reflective of physiological adaptations to live in an aerially exposed environment. Measured field temperatures where fingered limpets were collected demonstrated that limpets have a narrow thermal safety margin for aerobic performance, and currently experience multiple days where summer temperatures might exceed their threshold limits.

Microvascular anastomosis simulation using a chicken thigh model: Interval versus massed training.

PubMed

Schoeff, Stephen; Hernandez, Brian; Robinson, Derek J; Jameson, Mark J; Shonka, David C

2017-11-01

To compare the effectiveness of massed versus interval training when teaching otolaryngology residents microvascular suturing on a validated microsurgical model. Otolaryngology residents were placed into interval (n = 7) or massed (n = 7) training groups. The interval group performed three separate 30-minute practice sessions separated by at least 1 week, and the massed group performed a single 90-minute practice session. Both groups viewed a video demonstration and recorded a pretest prior to the first training session. A post-test was administered following the last practice session. At an academic medical center, 14 otolaryngology residents were assigned using stratified randomization to interval or massed training. Blinded evaluators graded performance using a validated microvascular Objective Structured Assessment of Technical Skill tool. The tool is comprised of two major components: task-specific score (TSS) and global rating scale (GRS). Participants also received pre- and poststudy surveys to compare subjective confidence in multiple aspects of microvascular skill acquisition. Overall, all residents showed increased TSS and GRS on post- versus pretest. After completion of training, the interval group had a statistically significant increase in both TSS and GRS, whereas the massed group's increase was not significant. Residents in both groups reported significantly increased levels of confidence after completion of the study. Self-directed learning using a chicken thigh artery model may benefit microsurgical skills, competence, and confidence for resident surgeons. Interval training results in significant improvement in early development of microvascular anastomosis skills, whereas massed training does not. NA. Laryngoscope, 127:2490-2494, 2017. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

Using Performance Assessment Model in Physics Laboratory to Increase Students’ Critical Thinking Disposition

NASA Astrophysics Data System (ADS)

Emiliannur, E.; Hamidah, I.; Zainul, A.; Wulan, A. R.

2017-09-01

Performance Assessment Model (PAM) has been developed to represent the physics concepts which able to be devided into five experiments: 1) acceleration due to gravity; 2) Hooke’s law; 3) simple harmonic motion; 4) work-energy concepts; and 5) the law of momentum conservation. The aim of this study was to determine the contribution of PAM in physics laboratory to increase students’ Critical Thinking Disposition (CTD) at senior high school. Subject of the study were 11th grade consist 32 students of a senior high school in Lubuk Sikaping, West Sumatera. The research used one group pretest-postest design. Data was collected through essay test and questionnaire about CTD. Data was analyzed using quantitative way with N-gain value. This study concluded that performance assessmet model effectively increases the N-gain at medium category. It means students’ critical thinking disposition significant increase after implementation of performance assessment model in physics laboratory.

Characterization of MoS2-Graphene Composites for High-Performance Coin Cell Supercapacitors.

PubMed

Bissett, Mark A; Kinloch, Ian A; Dryfe, Robert A W

2015-08-12

Two-dimensional materials, such as graphene and molybdenum disulfide (MoS2), can greatly increase the performance of electrochemical energy storage devices because of the combination of high surface area and electrical conductivity. Here, we have investigated the performance of solution exfoliated MoS2 thin flexible membranes as supercapacitor electrodes in a symmetrical coin cell arrangement using an aqueous electrolyte (Na2SO4). By adding highly conductive graphene to form nanocomposite membranes, it was possible to increase the specific capacitance by reducing the resistivity of the electrode and altering the morphology of the membrane. With continued charge/discharge cycles the performance of the membranes was found to increase significantly (up to 800%), because of partial re-exfoliation of the layered material with continued ion intercalation, as well as increasing the specific capacitance through intercalation pseudocapacitance. These results demonstrate a simple and scalable application of layered 2D materials toward electrochemical energy storage.

Relationship of pectoralis major muscle size with bench press and bench throw performances.

PubMed

Akagi, Ryota; Tohdoh, Yukihiro; Hirayama, Kuniaki; Kobayashi, Yuji

2014-06-01

This study examined the relationship of muscle size indices of the pectoralis major muscle with bench press and bench throw performances in 18 male collegiate athletes. The maximal cross-sectional area (MCSAMAx) and volume (MV) of the pectoralis major muscle were determined by magnetic resonance imaging. First, subjects were tested for their one repetition maximum bench press strength (1RMBP) using a Smith machine. At a later date, subjects performed bench throws using the Smith machine with several different loads ranging from 30.0 kg to 90% of 1RMBP. Barbell positions were measured by a linear position transducer, and bench throw power was calculated using a dynamic equation. Three trials were performed for each load. In all the trials, the maximal peak power was adopted as bench throw peak power (PPBT). The 1RMBP was significantly correlated with MCSAMAx. Similarly, the correlation coefficient between MV and PPBT was significant. In contrast to the y-intercept of the MV-PPBT regression line, that of the MCSAMAx-1RMBP regression line was not significantly different from 0. These results suggested that, although the dependence on pectoralis major muscle size is slightly different between bench press strength and bench throw power, the pectoralis major muscle size has a significant impact on bench press and throw performances. Greater muscle size leads to heavier body weight, which can be a negative factor in some sports. We therefore recommend that athletes and their coaches develop training programs for improving sports performance by balancing the advantage of increased muscle size and the potential disadvantage of increased body weight.

Alcohol affects brain functional connectivity and its coupling with behavior: greater effects in male heavy drinkers.

PubMed

Shokri-Kojori, E; Tomasi, D; Wiers, C E; Wang, G-J; Volkow, N D

2017-08-01

Acute and chronic alcohol exposure significantly affect behavior but the underlying neurobiological mechanisms are still poorly understood. Here, we used functional connectivity density (FCD) mapping to study alcohol-related changes in resting brain activity and their association with behavior. Heavy drinkers (HD, N=16, 16 males) and normal controls (NM, N=24, 14 males) were tested after placebo and after acute alcohol administration. Group comparisons showed that NM had higher FCD in visual and prefrontal cortices, default mode network regions and thalamus, while HD had higher FCD in cerebellum. Acute alcohol significantly increased FCD within the thalamus, impaired cognitive and motor functions, and affected self-reports of mood/drug effects in both groups. Partial least squares regression showed that alcohol-induced changes in mood/drug effects were associated with changes in thalamic FCD in both groups. Disruptions in motor function were associated with increases in cerebellar FCD in NM and thalamus FCD in HD. Alcohol-induced declines in cognitive performance were associated with connectivity increases in visual cortex and thalamus in NM, but in HD, increases in precuneus FCD were associated with improved cognitive performance. Acute alcohol reduced 'neurocognitive coupling', the association between behavioral performance and FCD (indexing brain activity), an effect that was accentuated in HD compared with NM. Findings suggest that reduced cortical connectivity in HD contribute to decline in cognitive abilities associated with heavy alcohol consumption, whereas increased cerebellar connectivity in HD may have compensatory effects on behavioral performance. The results reveal how drinking history alters the association between brain FCD and individual differences in behavioral performance.

Fermentation performance of lager yeast in high gravity beer fermentations with different sugar supplementations.

PubMed

Lei, Hongjie; Xu, Huaide; Feng, Li; Yu, Zhimin; Zhao, Haifeng; Zhao, Mouming

2016-11-01

The effects of glucose, sucrose and maltose supplementations on the fermentation performance and stress tolerance of lager yeast (Saccharomyces pastorianus) during high gravity (18°P) and very high gravity (24°P) fermentations were studied. Results showed that throughout 18°P wort fermentation, fermentation performance of lager yeast was significantly improved by glucose or sucrose supplementation, compared with maltose supplementation, especially for sucrose supplementation increasing wort fermentability and ethanol production by 6% and 8%, respectively. However, in the later stage of 24°P wort fermentation, fermentation performance of lager yeast was dramatically improved by maltose supplementation, which increased wort fermentability and ethanol production by 14% and 10%, respectively, compared with sucrose supplementation. Furthermore, higher HSP12 expression level and more intracellular trehalose accumulation in yeast cells were observed by maltose supplementation with increase of the wort gravity from 18°P to 24°P, indicating higher stress response of yeast cells. The excretion of Gly and Ala, and the absorption of Pro in the later stage of fermentation were promoted by maltose supplementation. In addition, with increase of the wort gravity from 18°P to 24°P, higher alcohols level was decreased with maltose supplementation, while esters formation was increased significantly with glucose supplementation. This study suggested that the choice of optimal fermentable sugars maintaining better fermentation performance of lager yeast should be based on not only strain specificity, but also wort gravity. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

The more the merrier? Increasing group size may be detrimental to decision-making performance in nominal groups.

PubMed

Amir, Ofra; Amir, Dor; Shahar, Yuval; Hart, Yuval; Gal, Kobi

2018-01-01

Demonstrability-the extent to which group members can recognize a correct solution to a problem-has a significant effect on group performance. However, the interplay between group size, demonstrability and performance is not well understood. This paper addresses these gaps by studying the joint effect of two factors-the difficulty of solving a problem and the difficulty of verifying the correctness of a solution-on the ability of groups of varying sizes to converge to correct solutions. Our empirical investigations use problem instances from different computational complexity classes, NP-Complete (NPC) and PSPACE-complete (PSC), that exhibit similar solution difficulty but differ in verification difficulty. Our study focuses on nominal groups to isolate the effect of problem complexity on performance. We show that NPC problems have higher demonstrability than PSC problems: participants were significantly more likely to recognize correct and incorrect solutions for NPC problems than for PSC problems. We further show that increasing the group size can actually decrease group performance for some problems of low demonstrability. We analytically derive the boundary that distinguishes these problems from others for which group performance monotonically improves with group size. These findings increase our understanding of the mechanisms that underlie group problem-solving processes, and can inform the design of systems and processes that would better facilitate collective decision-making.

Performance of large-bore tapered-roller bearings under combined radial and thrust load at shaft speeds to 15,000 rpm

NASA Technical Reports Server (NTRS)

Parker, R. J.; Signer, H. R.

1977-01-01

The performance of 120.65-mm bore tapered roller bearings was investigated at shaft speeds up to 15,000 rpm. Temperature distribution and bearing heat generation were determined as a function of shaft speed, radial and thrust loads, lubricant flow rate, and lubricant inlet temperature. Lubricant was supplied by either jets or by a combination of holes through the cone directly to the cone-rib contact and jets at the roller small-end side. Cone-rib lubrication significantly improved high-speed tapered-roller bearing performance, yielding lower cone-face temperatures and lower power loss and allowing lower lubricant flow rates for a given speed condition. Bearing temperatures increased with increased shaft speed and decreased with increased lubricant flow rate. Bearing power loss increased with increased shaft speed and increased lubricant flow rate.

Propulsion system-flight control integration and optimization: Flight evaluation and technology transition

NASA Technical Reports Server (NTRS)

Burcham, Frank W., Jr.; Gilyard, Glenn B.; Myers, Lawrence P.

1990-01-01

Integration of propulsion and flight control systems and their optimization offers significant performance improvements. Research programs were conducted which have developed new propulsion and flight control integration concepts, implemented designs on high-performance airplanes, demonstrated these designs in flight, and measured the performance improvements. These programs, first on the YF-12 airplane, and later on the F-15, demonstrated increased thrust, reduced fuel consumption, increased engine life, and improved airplane performance; with improvements in the 5 to 10 percent range achieved with integration and with no changes to hardware. The design, software and hardware developments, and testing requirements were shown to be practical.

Energy harvesting influences electrochemical performance of microbial fuel cells

NASA Astrophysics Data System (ADS)

Lobo, Fernanda Leite; Wang, Xin; Ren, Zhiyong Jason

2017-07-01

Microbial fuel cells (MFCs) can be effective power sources for remote sensing, wastewater treatment and environmental remediation, but their performance needs significant improvement. This study systematically analyzes how active harvesting using electrical circuits increased MFC system outputs as compared to passive resistors not only in the traditional maximal power point (MPP) but also in other desired operating points such as the maximum current point (MCP) and the maximum voltage point (MVP). Results show that active harvesting in MPP increased power output by 81-375% and active harvesting in MCP increased Coulombic efficiency by 207-805% compared with resisters operated at the same points. The cyclic voltammograms revealed redox potential shifts and supported the performance data. The findings demonstrate that active harvesting is a very effective approach to improve MFC performance across different operating points.

Urban Latino children's physical activity levels and performance in interactive dance video games: effects of goal difficulty and goal specificity.

PubMed

Gao, Zan; Podlog, Leslie

2012-10-01

To examine the effects of different levels of goal specificity and difficulty on Latino children's performance and physical activity (PA) levels in an after-school program incorporating an interactive dance program (Dance Dance Revolution [DDR]; Konami Corporation). Comparison study. Rose Park Elementary School, Salt Lake City, Utah. Ninety-eight Latino children in the first through sixth grades, aged 7 to 13 years. After the pretest, the participants were randomly assigned into 1 of the following 3 goal-setting conditions: (1) easy, (2) difficult, and (3) best effort (hereinafter referred to as do-your-best goal). Participants' PA levels were measured using piezoelectric pedometers, and steps per minute were used as the outcome variable. Participants' total points for their dance on television screens were retrieved as their performance scores. These outcome variables were assessed again 8 weeks later (posttest score). The multivariate analysis of covariance yielded a significant main effect for the goal-setting condition. Follow-up tests revealed that children who set specific (easy or difficult) goals had significantly greater increased PA levels (mean scores, 10.34 for easy and 22.45 for difficult) and DDR performance (0.011 for easy and 0.67 for difficult) than those in the do-your-best group (0.83 for PA and 0.17 for performance). In addition, children's increased PA levels in the difficult-goal group were significantly higher than those in the easy-goal group. The easy- and difficult-goal groups show a significant improvement on DDR performance. The difficult- goal group also displays the highest improvement on PA levels. Strategies to enhance children's DDR performance and PA levels are discussed in relation to the extant goal-setting literature.

CFD analysis of heat transfer performance of graphene based hybrid nanofluid in radiators

NASA Astrophysics Data System (ADS)

Bharadwaj, Bharath R.; Sanketh Mogeraya, K.; Manjunath, D. M.; Rao Ponangi, Babu; Rajendra Prasad, K. S.; Krishna, V.

2018-04-01

For Improved performance of an automobile engine, Cooling systems are one of the critical systems that need attention. With increased capacity to carry away large amounts of wasted heat, performance of an engine is increased. Current research on Nano-fluids suggests that they offer higher heat transfer rate compared to that of conventional coolants. Hence this project seeks to investigate the use of hybrid-nanofluids in radiators so as to increase its heat transfer performance. Carboxyl Graphene and Graphene Oxide based nanoparticles were selected due to the very high thermal conductivity of Graphene. System Analysis of the radiator was performed by considering a small part of the whole automobile radiator modelled using SEIMENS NX. CFD analysis was conducted using ANSYS FLUENT® for the nanofluid defined and the increase in effectiveness was compared to that of conventional coolants. Usage of such nanofluids for a fixed cooling requirement in the future can lead to significant downsizing of the radiator.

Cardiorespiratory effects of inelastic chest wall restriction.

PubMed

Miller, Jordan D; Beck, Kenneth C; Joyner, Michael J; Brice, A Glenn; Johnson, Bruce D

2002-06-01

We examined the effects of chest wall restriction (CWR) on cardiorespiratory function at rest and during exercise in healthy subjects in an attempt to approximate the cardiorespiratory interactions observed in clinical conditions that result in restrictive lung and/or chest wall changes and a reduced intrathoracic space. Canvas straps were applied around the thorax and abdomen so that vital capacity was reduced by >35%. Data were acquired at rest and during cycle ergometry at 25 and 45% of peak workloads. CWR elicited significant increases in the flow-resistive work performed on the lung (160%) and the gastric pressure-time integral (>400%) at the higher workload, but it resulted in a decrease in the elastic work performed on the lung (56%) compared with control conditions. With CWR, heart rate increased and stroke volume (SV) fell, resulting in >10% fall in cardiac output at rest and during exercise at matched workloads (P < 0.05). Blood pressure and catecholamines were significantly elevated during CWR exercise conditions (P < 0.05). We conclude that CWR significantly impairs SV during exercise and that a compensatory increase in heart rate does not prevent a significant reduction in cardiac output. O(2) consumption appears to be maintained via increased extraction and a redistribution of blood flow via sympathetic activation.

Acute Effects of Three Different Stretching Protocols on the Wingate Test Performance

PubMed Central

Franco, Bruno L.; Signorelli, Gabriel R.; Trajano, Gabriel S.; Costa, Pablo B.; de Oliveira, Carlos G.

2012-01-01

The purpose of this study was to examine the acute effects of different stretching exercises on the performance of the traditional Wingate test (WT). Fifteen male participants performed five WT; one for familiarization (FT), and the remaining four after no stretching (NS), static stretching (SS), dynamic stretching (DS), and proprioceptive neuromuscular facilitation (PNF). Stretches were targeted for the hamstrings, quadriceps, and calf muscles. Peak power (PP), mean power (MP), and the time to reach PP (TP) were calculated. The MP was significantly lower when comparing the DS (7.7 ± 0.9 W/kg) to the PNF (7.3 ± 0.9 W/kg) condition (p < 0.05). For PP, significant differences were observed between more comparisons, with PNF stretching providing the lowest result. A consistent increase of TP was observed after all stretching exercises when compared to NS. The results suggest the type of stretching, or no stretching, should be considered by those who seek higher performance and practice sports that use maximal anaerobic power. Key points The mean power was significantly lower when comparing dynamic stretching.to proprioceptive neuromuscular facilitation. For peak power, significant differences were observed between more comparisons, with proprioceptive neuromuscular facilitation stretching providing the lowest result. A consistent increase of time to reach the peak was observed after all stretching exercises when compared to non-stretching. The type of stretching, or no stretching, should be considered by those who seek higher performance and practice sports that use maximal anaerobic power. PMID:24149116

Effects of age, task, and frequency on variability of finger tapping.

PubMed

Sommervoll, Yngve; Ettema, Gertjan; Vereijken, Beatrix

2011-10-01

The goal was to assess whether prior studies might have overestimated performance variability in older adults in dual task conditions by relying on primary motor tasks that are not constant with aging. 30 younger and 31 older adults performed a bimanual tapping task at four different frequencies in isolation or concurrently with a secondary task. Results showed that performance of younger and older adults was not significantly different in performing the tapping task at all frequencies and with either secondary task, as indicated by mean tapping performance and low number of errors in the secondary tasks. Both groups showed increased variability as tapping frequency increased and with the presence of a secondary task. Tapping concurrently while reading words increased tapping variability more than tapping concurrently while naming colours. Although older participants' performances were overall more variable, no interaction effects with age were found and at the highest frequencies of tapping, younger and older participants did not differ in performance.

Impact of supplementing diets with propolis on productive performance, egg quality traits and some haematological variables of laying hens.

PubMed

Abdel-Kareem, A A A; El-Sheikh, T M

2017-06-01

One hundred and twenty eight, 28-weeks-old Lohmann LSL hybrid layers were used in this experiment, which lasted 12 weeks to investigate the effect of propolis supplementation on the productive performance, egg quality traits and haematological variables of laying hens. All hens were randomly classified into four equal experimental groups, eight replicates (4 birds/each). Hens in group 1 were fed on a commercial diet and considered as control group, while those in groups 2, 3 and 4 were fed on the same commercial diet and supplemented with 250, 500 and 1000 mg propolis/kg diet. The obtained results revealed that daily feed consumption/hen increased insignificantly with increasing propolis level than that of the control group. Regarding the means of egg mass and egg production rate, it was observed that the laying hens fed diets containing 250 and 1000 mg propolis/kg significantly (p < 0.05) produced more and heaver egg in comparison with control group. External egg quality traits have not affected with increasing the level of propolis, while eggshell weight was significantly (p < 0.05) increased. The internal egg quality traits except albumen and yolk percentages increased significantly (p < 0.05) with increasing propolis level for treated hens as compared to those in the control. Concerning the haematological parameters, the results showed that the levels of total protein and globulin increased significantly with increasing propolis level, while cholesterol and liver enzymes were significantly decreased (p < 0.05). Heterophils count of hens in the treated groups significantly decreased, whereas the lymphocyte count significantly increased, resulting in a decreased H/L ratio than that of the control group. Thus, it could be concluded that the supplementation of 250 mg propolis/kg diet is highly recommended to improving egg production, blood constituent and haematological parameters of the commercial laying hens. Journal of Animal Physiology and Animal Nutrition © 2015 Blackwell Verlag GmbH.

Effects of general, specific and combined warm-up on explosive muscular performance

PubMed Central

Henriquez–Olguín, C; Beltrán, AR; Ramírez, MA; Labarca, C; Cornejo, M; Álvarez, C; Ramírez-Campillo, R

2015-01-01

The purpose of this study was to compare the acute effects of general, specific and combined warm-up (WU) on explosive performance. Healthy male (n = 10) subjects participated in six WU protocols in a crossover randomized study design. Protocols were: passive rest (PR; 15 min of passive rest), running (Run; 5 min of running at 70% of maximum heart rate), stretching (STR; 5 min of static stretching exercise), jumping [Jump; 5 min of jumping exercises – 3x8 countermovement jumps (CMJ) and 3x8 drop jumps from 60 cm (DJ60)], and combined (COM; protocols Run+STR+Jump combined). Immediately before and after each WU, subjects were assessed for explosive concentric-only (i.e. squat jump – SJ), slow stretch-shortening cycle (i.e. CMJ), fast stretch-shortening cycle (i.e. DJ60) and contact time (CT) muscle performance. PR significantly reduced SJ performance (p =0.007). Run increased SJ (p =0.0001) and CMJ (p =0.002). STR increased CMJ (p =0.048). Specific WU (i.e. Jump) increased SJ (p =0.001), CMJ (p =0.028) and DJ60 (p =0.006) performance. COM increased CMJ performance (p =0.006). Jump was superior in SJ performance vs. PR (p =0.001). Jump reduced (p =0.03) CT in DJ60. In conclusion, general, specific and combined WU increase slow stretch-shortening cycle (SSC) muscle performance, but only specific WU increases fast SSC muscle performance. Therefore, to increase fast SSC performance, specific fast SSC muscle actions must be included during the WU. PMID:26060335

Pharmacokinetic and pharmacodynamic interactions between zolpidem and caffeine.

PubMed

Cysneiros, R M; Farkas, D; Harmatz, J S; von Moltke, L L; Greenblatt, D J

2007-07-01

The kinetic and dynamic interaction of caffeine and zolpidem was evaluated in a double-blind, single-dose, six-way crossover study of 7.5 mg zolpidem (Z) or placebo (P) combined with low-dose caffeine (250 mg), high-dose caffeine (500 mg), or placebo. Caffeine coadministration modestly increased maximum plasma concentration (C(max)) and area under the plasma concentration-time curve of zolpidem by 30-40%, whereas zolpidem did not significantly affect the pharmacokinetics of caffeine or its metabolites. Compared to P+P, Z+P significantly increased sedation, impaired digit-symbol substitution test performance, slowed tapping speed and reaction time, increased EEG relative beta amplitude, and impaired delayed recall. Caffeine partially, but not completely, reversed most pharmacodynamic effects of zolpidem. Thus, caffeine only incompletely reverses zolpidem's sedative and performance-impairing effects, and cannot be considered as an antidote to benzodiazepine agonists.

Performance time transformed by count as a determinant of difficulty in the Shotokan karate Heian kata set.

PubMed

Layton, C; Lawrence, J M

1997-06-01

Black-belt subjects (10 men) were timed on each of the five Heian kata and the scores transformed by count. Trend analyses showed that increased performance time was significantly related to assumed complexity in Heian ranking.

Changes in Shotokan karate black-belt Heian kata performance times: a longitudinal study.

PubMed

Layton, C; Lawrence, J M; Moran, P

1999-12-01

10 experienced black-belt subjects were individually timed on each of the five Heian kata and then timed again four years later. Performance time increased significantly in four of the kata, and this was interpreted as a positive progression.

Process-Oriented Guided Inquiry Learning Strategy Enhances Students’ Higher Level Thinking Skills in a Pharmaceutical Sciences Course

PubMed Central

Verlinden, Nathan; Kruger, Nicholas; Carroll, Ailey; Trumbo, Tiffany

2015-01-01

Objective. To determine if the process-oriented guided inquiry learning (POGIL) teaching strategy improves student performance and engages higher-level thinking skills of first-year pharmacy students in an Introduction to Pharmaceutical Sciences course. Design. Overall examination scores and scores on questions categorized as requiring either higher-level or lower-level thinking skills were compared in the same course taught over 3 years using traditional lecture methods vs the POGIL strategy. Student perceptions of the latter teaching strategy were also evaluated. Assessment. Overall mean examination scores increased significantly when POGIL was implemented. Performance on questions requiring higher-level thinking skills was significantly higher, whereas performance on questions requiring lower-level thinking skills was unchanged when the POGIL strategy was used. Student feedback on use of this teaching strategy was positive. Conclusion. The use of the POGIL strategy increased student overall performance on examinations, improved higher-level thinking skills, and provided an interactive class setting. PMID:25741027

Subvocal articulatory rehearsal during verbal working memory in multiple sclerosis.

PubMed

Sweet, Lawrence H; Vanderhill, Susan D; Jerskey, Beth A; Gordon, Norman M; Paul, Robert H; Cohen, Ronald A

2010-10-01

This study was designed to examine verbal working memory (VWM) components among multiple sclerosis (MS) patients and determine the influence of information processing speed. Of two frequently studied VWM sub-components, subvocal rehearsal was expected to be more affected by MS than short-term memory buffering. Furthermore, worse subvocal rehearsal was predicted to be specifically related to slower cognitive processing. Fifteen MS patients were administered a neuropsychological battery assessing VWM, processing speed, mood, fatigue, and disability. Participants performed a 2-Back VWM task with modified nested conditions designed to increase subvocal rehearsal (via inter-stimulus interval) and short-term memory buffering demands (via phonological similarity). Performance during these 2-Back conditions did not significantly differ and both exhibited strong positive correlations with disability. However, only scores on the subvocal rehearsal 2-Back were significantly related to performance on the remaining test battery, including processing speed and depressive symptoms. Findings suggest that performance during increased subvocal rehearsal demands is specifically influenced by cognitive processing speed and depressive symptoms.

Improved DC and RF performance of InAlAs/InGaAs InP based HEMTs using ultra-thin 15 nm ALD-Al2O3 surface passivation

NASA Astrophysics Data System (ADS)

Asif, Muhammad; Chen, Chen; Peng, Ding; Xi, Wang; Zhi, Jin

2018-04-01

Owing to the great influence of surface passivation on DC and RF performance of InP-based HEMTs, the DC and RF performance of InAlAs/InGaAs InP HEMTs were studied before and after passivation, using an ultra-thin 15 nm atomic layer deposition Al2O3 layer. Increase in Cgs and Cgd was significantly limited by scaling the thickness of the Al2O3 layer. For verification, an analytical small-signal equivalent circuit model was developed. A significant increase in maximum transconductance (gm) up to 1150 mS/mm, drain current (IDS) up to 820 mA/mm and fmax up to 369.7 GHz was observed, after passivation. Good agreement was obtained between the measured and the simulated results. This shows that the RF performance of InP-based HEMTs can be improved by using an ultra-thin ALD-Al2O3 surface passivation.

Older parents are less responsive to a stressor in a long-lived seabird: a mechanism for increased reproductive performance with age?

PubMed

Heidinger, Britt J; Nisbet, Ian C T; Ketterson, Ellen D

2006-09-07

In many taxa, reproductive performance increases throughout the lifespan and this may occur in part because older adults invest more in reproduction. The mechanisms that facilitate an increase in reproductive performance with age, however, are poorly understood. In response to stressors, vertebrates release glucocorticoids, which enhance survival but concurrently shift investment away from reproduction. Consequently, when the value of current reproduction is high relative to the value of future reproduction and survival, as it is in older adults, life history theory predicts that the stress response should be suppressed. In this study, we tested the hypothesis that older parents would respond less strongly to a stressor in a natural, breeding population of common terns (Sterna hirundo). Common terns are long-lived seabirds and reproductive performance is known to increase throughout the lifespan of this species. As predicted, the maximum level of glucocorticoids released in response to handling stress decreased significantly with age. We suggest that suppression of the stress response may be an important physiological mechanism that facilitates an increase in reproductive performance with age.

Independent from muscle power and balance performance, a creatinine clearance below 65 ml/min is a significant and independent risk factor for falls and fall-related fractures in elderly men and women diagnosed with osteoporosis.

PubMed

Dukas, L; Schacht, E; Runge, M

2010-07-01

We assessed in a cross-sectional study in elderly men and women with osteoporosis, the association between the creatinine clearance (CrCl) and the performance in different balance and muscle power and function tests and found that a decreasing creatinine clearance was significantly associated with lower balance and muscle power. To determine if a creatinine clearance of <65 ml/min is significantly associated with decreasing muscle power and balance and an increased risk for falls and fractures. We assessed in a cross-sectional-study in 1781 German osteoporotic patients, the association between the CrCl, the physical performance, and the number of falls and fractures. Controlling for age, gender, BMI, and osteoporosis treatment (fracture analysis only), a decreasing CrCl was associated with lower physical performance in the timed-up-and-go test (corr -0.2337, P < 0.0001), chair-rising test (corr -0.1706, P < 0.001), and tandem-stand test (corr 0.2193, P < 0.0001), and a CrCl of <65 ml/min was associated with a significantly higher risk for falls (47.7% vs. 36.2%, P = 0.0008) and fall-related fractures (33.1% vs. 22.9%, P = 0.0003) compared with a CrCl of >or=65 ml/min. In this study, we found a significant gender-independent correlation between decreasing CrCl and lower performance in balance and muscle power tests. Reduced muscle power and balance may therefore be involved in the low creatinine clearance associated increased risk for falls and fall-related fractures. Furthermore, we found that a CrCl <65 ml/min., independent from the performance in muscle power, muscle function, and balance tests, is a significant risk factor for falls and fractures.

Rapid body mass loss affects erythropoiesis and hemolysis but does not impair aerobic performance in combat athletes.

PubMed

Reljic, D; Feist, J; Jost, J; Kieser, M; Friedmann-Bette, B

2016-05-01

Rapid body mass loss (RBML) before competition was found to decrease hemoglobin mass (Hbmass ) in elite boxers. This study aimed to investigate the underlying mechanisms of this observation. Fourteen well-trained combat athletes who reduced body mass before competitions (weight loss group, WLG) and 14 combat athletes who did not practice RBML (control group, CON) were tested during an ordinary training period (t-1), 1-2 days before an official competition (after 5-7 days RBML in WLG, t-2), and after a post-competition period (t-3). In WLG, body mass (-5.5%, range: 2.9-6.8 kg) and Hbmass (-4.1%) were significantly (P < 0.001) reduced after RBML and were still decreased by 1.6% (P < 0.05) and 2.6% (P < 0.001) at t-3 compared with t-1. After RBML, erythropoietin, reticulocytes, haptoglobin, triiodothyronine (FT3 ), and free androgen index (FAI) were decreased compared with t-1 and t-3. An increase occurred in ferritin and bilirubin. Peak treadmill-running performance and VO2peak did not change significantly, but performance at 4-mmol lactate threshold was higher after RBML (P < 0.05). In CON, no significant changes were found in any parameter. Apparently, the significant decrease in Hbmass after RBML in combat athletes was caused by impaired erythropoiesis and increased hemolysis without significant impact on aerobic performance capacity. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Performance of Radiant Heating Systems of Low-Energy Buildings

NASA Astrophysics Data System (ADS)

Sarbu, Ioan; Mirza, Matei; Crasmareanu, Emanuel

2017-10-01

After the introduction of plastic piping, the application of water-based radiant heating with pipes embedded in room surfaces (i.e., floors, walls, and ceilings), has significantly increased worldwide. Additionally, interest and growth in radiant heating and cooling systems have increased in recent years because they have been demonstrated to be energy efficient in comparison to all-air distribution systems. This paper briefly describes the heat distribution systems in buildings, focusing on the radiant panels (floor, wall, ceiling, and floor-ceiling). Main objective of this study is the performance investigation of different types of low-temperature heating systems with different methods. Additionally, a comparative analysis of the energy, environmental, and economic performances of floor, wall, ceiling, and floor-ceiling heating using numerical simulation with Transient Systems Simulation (TRNSYS) software is performed. This study showed that the floor-ceiling heating system has the best performance in terms of the lowest energy consumption, operation cost, CO2 emission, and the nominal boiler power. The comparison of the room operative air temperatures and the set-point operative air temperature indicates also that all radiant panel systems provide satisfactory results without significant deviations.

Visual acuity in young elite motorsport athletes: a preliminary report.

PubMed

Schneiders, Anthony G; Sullivan, S John; Rathbone, Emma J; Louise Thayer, A; Wallis, Laura M; Wilson, Alexandra E

2010-05-01

To determine whether elite motorsport athletes demonstrate superior levels of Visual Acuity than age and sex-matched controls. A cross-sectional observational study. A University vision and balance laboratory. Young male motorsport athletes from the New Zealand Elite Motorsport Academy and healthy age and sex-matched controls. Vision performance tests comprising; Static Visual Acuity (SVA), Dynamic Visual Acuity (DVA), Gaze Stabilization Test (GST), and the Perception Time Test (PTT). Motorsport athletes demonstrated superior visual acuity compared to age and sex-matched controls for all measures, and while this was not statistically significant for SVA, GST and DVA, it reached statistical significance for the PTT (p

The influence of test mode and visuospatial ability on mathematics assessment performance

NASA Astrophysics Data System (ADS)

Logan, Tracy

2015-12-01

Mathematics assessment and testing are increasingly situated within digital environments with international tests moving to computer-based testing in the near future. This paper reports on a secondary data analysis which explored the influence the mode of assessment—computer-based (CBT) and pencil-and-paper based (PPT)—and visuospatial ability had on students' mathematics test performance. Data from 804 grade 6 Singaporean students were analysed using the knowledge discovery in data design. The results revealed statistically significant differences between performance on CBT and PPT test modes across content areas concerning whole number algebraic patterns and data and chance. However, there were no performance differences for content areas related to spatial arrangements geometric measurement or other number. There were also statistically significant differences in performance between those students who possess higher levels of visuospatial ability compared to those with lower levels across all six content areas. Implications include careful consideration for the comparability of CBT and PPT testing and the need for increased attention to the role of visuospatial reasoning in student's mathematics reasoning.

Graduating general surgery resident operative confidence: perspective from a national survey.

PubMed

Fonseca, Annabelle L; Reddy, Vikram; Longo, Walter E; Gusberg, Richard J

2014-08-01

General surgical training has changed significantly over the last decade with work hour restrictions, increasing subspecialization, the expanding use of minimally invasive techniques, and nonoperative management for solid organ trauma. Given these changes, this study was undertaken to assess the confidence of graduating general surgery residents in performing open surgical operations and to determine factors associated with increased confidence. A survey was developed and sent to general surgery residents nationally. We queried them regarding demographics and program characteristics, asked them to rate their confidence (rated 1-5 on a Likert scale) in performing open surgical procedures and compared those who indicated confidence with those who did not. We received 653 responses from the fifth year (postgraduate year 5) surgical residents: 69% male, 68% from university programs, and 51% from programs affiliated with a Veterans Affairs hospital; 22% from small programs, 34% from medium programs, and 44% from large programs. Anticipated postresidency operative confidence was 72%. More than 25% of residents reported a lack of confidence in performing eight of the 13 operations they were queried about. Training at a university program, a large program, dedicated research years, future fellowship plans, and training at a program that performed a large percentage of operations laparoscopically was associated with decreased confidence in performing a number of open surgical procedures. Increased surgical volume was associated with increased operative confidence. Confidence in performing open surgery also varied regionally. Graduating surgical residents indicated a significant lack of confidence in performing a variety of open surgical procedures. This decreased confidence was associated with age, operative volume as well as type, and location of training program. Analyzing and addressing this confidence deficit merits further study. Copyright © 2014 Elsevier Inc. All rights reserved.

Postactivation potentiation: effect of various recovery intervals on bench press power performance.

PubMed

Ferreira, Sandra Lívia de Assis; Panissa, Valéria Leme Gonçalves; Miarka, Bianca; Franchini, Emerson

2012-03-01

Postactivation potentiation (PAP) is a strategy used to improve performance in power activities. The aim of this study was to determine if power during bench press exercise was increased when preceded by 1 repetition maximum (1RM) in the same exercise and to determine which time interval could optimize PAP response. For this, 11 healthy male subjects (age, 25 ± 4 years; height, 178 ± 6 cm; body mass, 74 ± 8 kg; bench press 1RM, 76 ± 19 kg) underwent 6 sessions. Two control sessions were conducted to determine both bench press 1RM and power (6 repetitions at 50% 1RM). The 4 experimental sessions were composed of a 1RM exercise followed by power sets with different recovery intervals (1, 3, 5, and 7 minutes), performed on different days, and determined randomly. Power values were measured via Peak Power equipment (Cefise, Nova Odessa, São Paulo, Brazil). The conditions were compared using an analysis of variance with repeated measures, followed by a Tukey test. The significance level was set at p < 0.05. There was a significant increase in PAP in concentric contractions after 7 minutes of recovery compared with the control and 1-minute recovery conditions (p < 0.05). Our results indicated that 7 minutes of recovery has generated an increase in PAP in bench press and that such a strategy could be applied as an interesting alternative to enhance the performance in tasks aimed at increasing upper-body power performance.

Enhancing social participation in young people with communication disabilities living in rural Australia: outcomes of a home-based intervention for using social media.

PubMed

Raghavendra, Parimala; Newman, Lareen; Grace, Emma; Wood, Denise

2015-01-01

The purpose of this study is to investigate the effectiveness of a home-based intervention using social media to enhance social networks of young people with disabilities and communication difficulties. Eight young people (M(age) = 15.4 years) with communication disabilities participated from two rural Australian towns. The intervention provided assistive technology and training to learn social media use. A mixed-method design combined pre- and post-assessments measuring changes in performance, satisfaction with performance, attainment on social media goals, and social network extension, and interviews investigated the way in which the intervention influenced social participation. Participants showed an increase in performance, and satisfaction with performance, on the Canadian Occupational Performance Measure; paired t-tests showed statistical significance at p <0.01. Wilcoxon Signed Ranks revealed a significant increase in the number of online communication partners, p <0.05. The interviews highlighted participants' and parents' perceptions of increased social connections, improved communication frequency and nature, and speech intelligibility and literacy as a result of the intervention. The findings suggest that learning to use social media leads to increase in social participation among rural-based young people with communication disabilities. In order to benefit from advantages of learning to use social media in rural areas, parents and service providers need knowledge and skills to integrate assistive technology with the Internet needs of this group.

The performance evaluation of a jet flap on an advanced supersonic harrier

NASA Technical Reports Server (NTRS)

Lipera, L. D.; Sandlin, D. R.

1984-01-01

The performance concept of a supersonic vertical and short takeoff and landing (V/STOL) fighter, model 279-3, modified to utilize a jet flap was evaluated. Replacing the rear nozzles of the 279-3 with the jet flap favorably alters the pressure distribution over the airfoil and dramatically increases lift. The result is a significant decrease in takeoff distance, an increase in payload, and an improvement in combat performance. To investigate the benefit in increased payload, the 279-3 and the jet flapped 279-3JF were modeled on the NASA Aircraft Synthesis (ACSYNT) computer code and flown on a 250 feet takeoff distance interdiction mission. The increase in payload weight that the 279-3JF could carry was converted into fuel in one case, and in another, converted to bomb load. When the fuel was increased, the 279-3JF penetrated into enemy territory almost four times the distance of 279-3, and therefore increased mission capability. When the bomb load was increased, the 279-3JF carried 14 bombs the same distance the 279-3 carried four. The increase in mission performance and improvements in turning rates was realized with only a small penalty in increased empty weight.

Increased Learning Time under Stimulus-Funded School Improvement Grants: High Hopes, Varied Implementation

ERIC Educational Resources Information Center

McMurrer, Jennifer

2012-01-01

Research has long suggested that significantly increasing quality time in school for teaching and learning can have a positive impact on student achievement. Recognizing this connection, federal guidance requires low-performing schools to increase student learning time if they are implementing two popular reform models using school improvement…

[Adsorption characteristics of acetone and butanone onto honeycomb ZSM-5 molecular sieve].

PubMed

Du, Juan; Luan, Zhi-Qiang; Xie, Qiang; Ye, Ping-Wei; Li, Kai; Wang, Xi-Qin

2013-12-01

Adsorption capacity of acetone and acetone-butanone mixture onto honeycomb ZSM-5 molecular sieve was measured in this paper, and the influences of relative humidity, initial adsorbate concentration and airflow velocity on the adsorption process were investigated. Besides, adsorption performance parameters were calculated by Wheeler's equation. The results showed that relative humidity had no obvious influence on the acetone adsorption performance, which suggests that this material has good hydrophobic ability; in the low concentration range, the dynamic saturated adsorption capacity of acetone increased with the increase of initial concentration, but in the occasion of high concentration of acetone gas (more than 9 mg x L(-1)), the dynamic saturated adsorption capacity maintained at a certain level and did not vary with the increase of initial concentration; the increase of air flow velocity resulted in significant increase of acetone adsorption rate constant, at the same time the critical layer thickness of the adsorbent bed also increased significantly. In the cases of acetone-butanone mixture, the adsorption capacity of butanone onto ZSM-5 was clearly higher than that of acetone.

Increased blood flow and vasculature in solar lentigo.

PubMed

Hasegawa, Kiyotaka; Fujiwara, Rumiko; Sato, Kiyoshi; Park, Ji-Youn; Kim, Sang Jin; Kim, Misun; Kang, Hee Young

2016-10-01

Solar lentigo (SL) is a hallmark of ultraviolet (UV)-induced photoaged skin and growing evidence implicates blood vessels in UV-associated pigmentation. In this study, we investigated whether the vasculatures are modified in SL. Twenty-five women with facial SL were enrolled and colorimetric and blood flow studies were performed. There was a significant increase in erythema which was associated with increased blood flow in the lesional skin compared with perilesional normal skin. Immunohistochemical studies with 24 facial SL biopsies consistently revealed a significant increase in vessel density accompanied by increased levels of vascular endothelial growth factor expression. CD68 immunoreactivity was significantly higher in lesional skin suggesting increased macrophage infiltration in SL. In conclusion, SL is characterized by increased blood flow and vasculature. These findings suggest the possible influence of the characteristics of vasculature on development of SL. © 2016 Japanese Dermatological Association.

Trajectories of total depression and depressive symptoms in prostate cancer patients receiving six months of hormone therapy.

PubMed

Sharpley, Christopher F; Christie, David R H; Bitsika, Vicki; Miller, Bradley J

2017-01-01

The aim of this study was to investigate the effects of hormone therapy (HT) on depression and depressive symptoms in prostate cancer patients undergoing 6 months of HT. One hundred two prostate cancer patients who had been prescribed HT completed the Zung Self-rating Depression Scale (SDS) and two questions about their sexual enjoyment and performance, plus a background questionnaire before HT, after 8 to 10 weeks of HT and again after 16 to 20 weeks of HT. There was a significant increase in SDS scores from before to during HT. High depression score before HT was a significant predictor of later increases in depression during HT. Increases in depressive symptoms were restricted to 8 of the 20 SDS symptoms, the most powerful change being in sexual anhedonia, which was a result of decreased ability to perform during sexual activity. The association between HT and elevated depression is confirmed, but the relative influence of sexual anhedonia over other depressive symptoms expands the understanding of this association. The effects of decreased ability to perform during sex appear to dominate the increase in depression during HT. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Effect of potential probiotic Rhodotorula benthica D30 on the growth performance, digestive enzyme activity and immunity in juvenile sea cucumber Apostichopus japonicus.

PubMed

Wang, Ji-hui; Zhao, Liu-qun; Liu, Jin-feng; Wang, Han; Xiao, Shan

2015-04-01

The effects of dietary addition of yeast Rhodotorula benthica (R. benthica) D30 which isolated from local sea mud at levels of 0 (control), 10(5), 10(6) and 10(7) CFU/g feed on the growth performance, digestive enzyme activity, immunity and disease resistance of juvenile sea cucumber Apostichopus japonicus were investigated. It was shown that dietary addition of R. benthica D30 significantly increased the growth rates of sea cucumbers (p < 0.05). The amylase activity, cellulase activity and alginase activity were increased for the animals from three probiotics treated groups. And with the supplemented concentration increased, the values of those digestive enzyme activities increased as well. Dietary addition of R. benthica D30 at the level of 10(7) CFU significantly increased the lysozyme, phagocytic and total nitric oxide synthase activity of A. japonicus (p < 0.05). While, the highest values of the phenoloxidase and alkaline phosphatase activity were found in sea cucumbers fed with R. benthica D30 at the level of 10(6) CFU. Whereas adding R. benthica D30 to diet had no significant effects on the total coelomocyte counts and acid phosphatase activity of A. japonicus (p > 0.05). It was observed that adding R. benthica D30 could significantly decrease the cumulative mortality of sea cucumbers. The present study demonstrated that dietary addition of R. benthica D30 could increase growth performance and some digestive enzyme activities, improve immunity and disease resistance of A. japonicus. And the medium (10(6) CFU) and high (10(7) CFU) additional levels showed better effects. It suggests that yeast R. benthica D30 could be a good probiotic for aquaculture. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effects of adding liquid DL-methionine hydroxy analogue-free acid to drinking water on growth performance and small intestinal morphology of nursery pigs.

PubMed

Kaewtapee, C; Krutthai, N; Poosuwan, K; Poeikhampha, T; Koonawootrittriron, S; Bunchasak, C

2010-06-01

This study was conducted to evaluate the effect of adding liquid DL-methionine hydroxy analogue free acid (LMA) to drinking water on growth performance, small intestinal morphology and volatile fatty acids in the caecum of nursery pigs. Twenty-four crossbred pigs (Large White x Landrace, BW approximately 18 kg) were divided into three groups with four replications of two piglets each. The piglets received drinking water without (control), with 0.05 or 0.10% LMA. The results indicated that adding LMA at 0.10% to drinking water significantly increased their weight gain, average daily feed intake (p < 0.05) and tended to improve the feed conversion ratio. Adding LMA to drinking water significantly increased their water intake and significantly reduced the pH of drinking water (p < 0.01), thus total plate count (p < 0.01) and Escherichia coli in drinking water was reduced (p < 0.05), while the total number of bacteria in the caecum was not significantly affected. Liquid DL-methionine hydroxy analogue free acid supplementation in drinking water tended to decrease pH in the stomach, duodenum, jejunum, colon and rectum. Furthermore, adding LMA at 0.10% significantly increased villous height in the duodenum, jejunum and ileum (p < 0.05), and the villous height:crypt depth ratio in the jejunum and ileum (p < 0.01) was higher, whereas acetic acid concentration in the caecum was significantly lower than in the control group. It could be concluded that adding LMA to drinking water improved growth performance of the nursery pigs because of high water quality and high nutrient utilization caused by an improvement of small intestinal morphology (not from nutritional effect of methionine source).

Exploring relationship between face-to-face interaction and team performance using wearable sensor badges.

PubMed

Watanabe, Jun-ichiro; Ishibashi, Nozomu; Yano, Kazuo

2014-01-01

Quantitative analyses of human-generated data collected in various fields have uncovered many patterns of complex human behaviors. However, thus far the quantitative evaluation of the relationship between the physical behaviors of employees and their performance has been inadequate. Here, we present findings demonstrating the significant relationship between the physical behaviors of employees and their performance via experiments we conducted in inbound call centers while the employees wore sensor badges. There were two main findings. First, we found that face-to-face interaction among telecommunicators and the frequency of their bodily movements caused by the face-to-face interaction had a significant correlation with the entire call center performance, which we measured as "Calls per Hour." Second, our trial to activate face-to-face interaction on the basis of data collected by the wearable sensor badges the employees wore significantly increased their performance. These results demonstrate quantitatively that human-human interaction in the physical world plays an important role in team performance.

Exploring Relationship between Face-to-Face Interaction and Team Performance Using Wearable Sensor Badges

PubMed Central

Watanabe, Jun-ichiro; Ishibashi, Nozomu; Yano, Kazuo

2014-01-01

Quantitative analyses of human-generated data collected in various fields have uncovered many patterns of complex human behaviors. However, thus far the quantitative evaluation of the relationship between the physical behaviors of employees and their performance has been inadequate. Here, we present findings demonstrating the significant relationship between the physical behaviors of employees and their performance via experiments we conducted in inbound call centers while the employees wore sensor badges. There were two main findings. First, we found that face-to-face interaction among telecommunicators and the frequency of their bodily movements caused by the face-to-face interaction had a significant correlation with the entire call center performance, which we measured as “Calls per Hour.” Second, our trial to activate face-to-face interaction on the basis of data collected by the wearable sensor badges the employees wore significantly increased their performance. These results demonstrate quantitatively that human-human interaction in the physical world plays an important role in team performance. PMID:25501748

Effects of mindfulness and psychoeducation on working memory in adult ADHD: A randomised, controlled fMRI study.

PubMed

Bachmann, Katharina; Lam, Alexandra P; Sörös, Peter; Kanat, Manuela; Hoxhaj, Eliza; Matthies, Swantje; Feige, Bernd; Müller, Helge; Özyurt, Jale; Thiel, Christiane M; Philipsen, Alexandra

2018-07-01

Adult attention-deficit/hyperactivity disorder (ADHD) is a serious mental disorder associated with impaired neurocognitive performance related to working memory function. Recent clinical trials have suggested that mindfulness is a promising intervention in adults with ADHD. We performed a randomised controlled clinical trial to investigate working memory (WM) with an n-back task in adults with ADHD during fMRI before and after an 8-week mindfulness intervention (MAP) compared with psychoeducation (PE). ADHD symptoms were assessed using the self- and observer-rated Conners Adult ADHD Rating Scales (CAARS). The complete pre-post data of 21 MAP and 19 PE participants were analysed. We found no group difference in ADHD symptoms or task performance at the pre-measurement, but there was a significant decrease in ADHD symptoms and significant improvement in task performance in both groups at the post-measurement. Furthermore, we found a significant increase in task-related activation in the right parietal lobe, with no difference between groups. Exploratory two-sample paired t-tests revealed significant increased brain activation after MAP in the bilateral inferior parietal lobule, right posterior insula and right precuneus. A decrease in self-rated 'Inattention/Memory Problems' after MAP compared to baseline was associated with stronger activation in parts of the left putamen, globus pallidus and thalamus. Copyright © 2018 Elsevier Ltd. All rights reserved.

Supplementation with Hualian No. 4 wild bitter gourd (Momordica charantia Linn. var. abbreviata ser.) extract increases anti-fatigue activities and enhances exercise performance in mice

PubMed Central

HSIAO, Chien-Yu; CHEN, Yi-Ming; HSU, Yi-Ju; HUANG, Chi-Chang; SUNG, Hsin-Ching; CHEN, Sheng-Shih

2017-01-01

Hualian No. 4 wild bitter gourd (WBG) is a specific vegetable cultivated by the Hualien District Agricultural Research and Extension Station in Taiwan. WBG is commonly consumed as a vegetable and used as a popular folk medicine. However, few studies have demonstrated the effects of WBG supplementation on exercise performance, physical fatigue and the biochemical profile. The purpose of this study was to evaluate the potential beneficial effects of WBG extract on fatigue and ergogenic functions following physiological challenge. Three groups of male ICR mice (n=8 per group) were orally administered 0, 1 or 2.5 g/kg/day of WBG for 4 weeks. They were respectively designated the vehicle, WBG-1X and WBG-2.5X groups. WBG significantly decreased body weight (BW) and epididymal fat pad (EFP) weight. Concerning physical performance, WBG supplementation dose-dependently increased grip strength and endurance swimming time. Concerning anti-fatigue activity, WBG decreased levels of serum lactate, ammonia, creatine kinase and blood urea nitrogen, and economized glucose metabolism after acute exercise challenge. Glycogen in the liver and gastrocnemius muscle dose-dependently increased with WBG treatment. Concerning the biochemical profile, WBG treatment significantly decreased alanine aminotransferase (ALT), blood urea nitrogen (BUN) and urea acid (UA), and increased total protein (TP). Therefore, 4-week supplementation with WBG may decrease white adipose weight, enhance energy economy, increase glycogen storage to enhance exercise performance and reduce fatigue. PMID:28458274

The relation of depression and anxiety to life-stress and achievement in students.

PubMed

Andrews, Bernice; Wilding, John M

2004-11-01

An apparent increase in seriously disturbed students consulting student health services in the UK has led to concern that increasing financial difficulties and other outside pressures may affect student mental health and academic performance. The current research investigated whether student anxiety and depression increases after college entry, the extent to which adverse life experiences contribute to any increases, and the impact of adversity, anxiety and depression on exam performance. 351 UK-domiciled undergraduates completed questionnaires one month before university entry and mid-course. The Hospital Anxiety and Depression Scale (HADS: Zigmond & Snaith, 1983) was administered at both time points and a modified List of Threatening Experiences (Brugha, Bebbington, Tennant, & Hurry, 1985) was administered mid-course. By mid-course 9% of previously symptom-free students became depressed and 20% became anxious at a clinically significant level. Of those previously anxious or depressed 36% had recovered. After adjusting for pre-entry symptoms, financial difficulties made a significant independent contribution to depression and relationship difficulties independently predicted anxiety. Depression and financial difficulties mid-course predicted a decrease in exam performance from first to second year. This is the first study to confirm empirically that financial and other difficulties can increase British students' levels of anxiety and depression and that financial difficulties and depression can affect academic performance. However, university life may also have a beneficial effect for some students with pre-existing conditions. With widening participation in higher education, the results have important implications for educational and health policies.

Influence of Adding Single-Joint Exercise to a Multijoint Resistance Training Program in Untrained Young Women.

PubMed

Barbalho, Matheus; Gentil, Paulo; Raiol, Rodolfo; Fisher, James; Steele, James; Coswig, Victor

2018-05-15

Barbalho, M, Gentil, P, Raiol, R, Fisher, J, Steele, J, and Coswig, V. Influence of adding single-joint exercise to a multijoint resistance training program in untrained young women. J Strength Cond Res XX(X): 000-000, 2018-The aim of the present study was to investigate the effects of adding single-joint (SJ) exercises to a multijoint (MJ) resistance training (RT) program on muscle strength and anthropometric measures of young women. Twenty untrained women were divided into a group that performed only MJ exercises or a group that performed both SJ and MJ exercises (MJ + SJ). Before and after 8 weeks of training, the participants were tested for 10 repetition maximum (10RM). Flexed arm circumference and triceps and biceps skinfold thickness were also measured. Both groups significantly decreased biceps (-3.60% for MJ and -3.55% for MJ + SJ) and triceps skinfold (-3.05% for MJ and -2.98% for MJ + SJ), with no significant difference between them. Flexed arm circumference significantly increased in both groups; however, increases in MJ + SJ (4.39%) were significantly greater than MJ (3.50%). Increases in 10RM load in elbow extension (28.2% for MJ and 28.0% for MJ + SJ), elbow flexion (29.8% for MJ and 28.7% for MJ + SJ), and knee extension (26.92% for MJ and 23.86% for MJ + SJ) were all significant and not different between groups. The results showed that adding SJ exercises to an MJ RT program resulted in no benefits in muscle performance or anthropometric changes in untrained women.

Held in contempt: the psychological, interpersonal, and performance consequences of contempt in a work context.

PubMed

Melwani, Shimul; Barsade, Sigal G

2011-09-01

Guided by a social function of emotions perspective, the authors examined a model of the psychological, interpersonal, and performance consequences of contempt in a series of 3 experiments that tested the outcomes of being a recipient of contempt in the work domain. In these experiments, participants engaged in a business strategy simulation with a virtual partner-a computer programmed to give contemptuous and other types of feedback. In Study 1, which examined the task performance and interpersonal outcomes of contempt, recipients of contempt had significantly better task performance but also significantly more interpersonal aggressiveness toward their virtual partners compared with recipients of failure, angry, or neutral feedback. Study 2 examined 3 psychological outcomes mediating the contempt-task performance/aggression relationship: self-esteem, returned feelings of contempt, and activation levels. Lowered levels of implicit self-esteem and greater levels of activation significantly mediated the relationship between receiving contempt and task performance, whereas the contempt-aggression relationship was mediated by lowered implicit self-esteem and increased feelings of returned contempt. Study 3 examined status as a moderator of these relationships. Low-status recipients had significantly better task performance than did equal-status recipients, who performed significantly better than did the high-status recipients of contempt. In addition, low-status recipients displayed significantly lower levels of aggression in response to contempt than did equal-status and high-status recipients. PsycINFO Database Record (c) 2011 APA, all rights reserved.

Accuracy of Surgery Clerkship Performance Raters.

ERIC Educational Resources Information Center

Littlefield, John H.; And Others

1991-01-01

Interrater reliability in numerical ratings of clerkship performance (n=1,482 students) in five surgery programs was studied. Raters were classified as accurate or moderately or significantly stringent or lenient. Results indicate that increasing the proportion of accurate raters would substantially improve the precision of class rankings. (MSE)

Ontogeny of the morphology-performance axis in an amphibious fish (Kryptolebias marmoratus).

PubMed

Styga, Joseph M; Houslay, Thomas M; Wilson, Alastair J; Earley, Ryan L

2017-12-01

Establishing links between morphology and performance is important for understanding the functional, ecological, and evolutionary implications of morphological diversity. Relationships between morphology and performance are expected to be age dependent if, at different points during ontogeny, animals must perform in different capacities to achieve high fitness returns. Few studies have examined how the relationship between form and function changes across ontogeny. Here, we assess this relationship in the amphibious mangrove rivulus (Kryptolebias marmoratus) fish, a species that is both capable of and reliant on "tail-flip jumping" for terrestrial locomotion. Tail-flip jumping entails an individual transferring its weight to the caudal region of the body, launching itself from the substrate to navigate to new aquatic or semi-aquatic habitats. By combining repeated trials of jumping performance in 237 individuals from distinct age classes with a clearing and staining procedure to visualize bones in the caudal region, we test the hypotheses that as age increases (i) average jumping performance (body lengths jumped) will increase, (ii) the amount of variation for each trait will change, and (iii) the patterns of covariation/correlation among traits, which tell us about the integration of form with function, will also change. We find a significant increase in size-adjusted jumping performance with age, and modification to the correlation structure among traits across ontogeny. However, we also find that significant links between form and function evident in young animals disappear at later ontogenetic stages. Our study suggests that different functional mechanisms may be associated with high performance at different stages of development. © 2018 Wiley Periodicals, Inc.

Nitrogen-Doped Carbon Nanotube/Graphite Felts as Advanced Electrode Materials for Vanadium Redox Flow Batteries.

PubMed

Wang, Shuangyin; Zhao, Xinsheng; Cochell, Thomas; Manthiram, Arumugam

2012-08-16

Nitrogen-doped carbon nanotubes have been grown, for the first time, on graphite felt (N-CNT/GF) by a chemical vapor deposition approach and examined as an advanced electrode for vanadium redox flow batteries (VRFBs). The unique porous structure and nitrogen doping of N-CNT/GF with increased surface area enhances the battery performance significantly. The enriched porous structure of N-CNTs on graphite felt could potentially facilitate the diffusion of electrolyte, while the N-doping could significantly contribute to the enhanced electrode performance. Specifically, the N-doping (i) modifies the electronic properties of CNT and thereby alters the chemisorption characteristics of the vanadium ions, (ii) generates defect sites that are electrochemically more active, (iii) increases the oxygen species on CNT surface, which is a key factor influencing the VRFB performance, and (iv) makes the N-CNT electrochemically more accessible than the CNT.

Extended Performance 8-cm Mercury Ion Thruster

NASA Technical Reports Server (NTRS)

Mantenieks, M. A.

1981-01-01

A slightly modified 8-cm Hg ion thruster demonstrated significant increase in performance. Thrust was increased by almost a factor of five over that of the baseline thruster. Thruster operation with various three grid ion optics configurations; thruster performance as a function of accelerator grid open area, cathode baffle, and cathode orifice size; and a life test of 614 hours at a beam current of 250 mA (17.5 mN thrust) are discussed. Highest thruster efficiency was obtained with the smallest open area accelerator grid. The benefits in efficiency from the low neutral loss grids were mitigated, however, by the limitation such grids place on attainable ion beam current densities. The thruster components suffered negligible weight losses during a life test, which indicated that operation of the 8-cm thruster at extended levels of thrust and power is possible with no significant loss of lifetime.

Augmented Reality as a Countermeasure for Sleep Deprivation.

PubMed

Baumeister, James; Dorrlan, Jillian; Banks, Siobhan; Chatburn, Alex; Smith, Ross T; Carskadon, Mary A; Lushington, Kurt; Thomas, Bruce H

2016-04-01

Sleep deprivation is known to have serious deleterious effects on executive functioning and job performance. Augmented reality has an ability to place pertinent information at the fore, guiding visual focus and reducing instructional complexity. This paper presents a study to explore how spatial augmented reality instructions impact procedural task performance on sleep deprived users. The user study was conducted to examine performance on a procedural task at six time points over the course of a night of total sleep deprivation. Tasks were provided either by spatial augmented reality-based projections or on an adjacent monitor. The results indicate that participant errors significantly increased with the monitor condition when sleep deprived. The augmented reality condition exhibited a positive influence with participant errors and completion time having no significant increase when sleep deprived. The results of our study show that spatial augmented reality is an effective sleep deprivation countermeasure under laboratory conditions.

Quantitative Evaluation of Performance during Robot-assisted Treatment.

PubMed

Peri, E; Biffi, E; Maghini, C; Servodio Iammarrone, F; Gagliardi, C; Germiniasi, C; Pedrocchi, A; Turconi, A C; Reni, G

2016-01-01

This article is part of the Focus Theme of Methods of Information in Medicine on "Methodologies, Models and Algorithms for Patients Rehabilitation". The great potential of robots in extracting quantitative and meaningful data is not always exploited in clinical practice. The aim of the present work is to describe a simple parameter to assess the performance of subjects during upper limb robotic training exploiting data automatically recorded by the robot, with no additional effort for patients and clinicians. Fourteen children affected by cerebral palsy (CP) performed a training with Armeo®Spring. Each session was evaluated with P, a simple parameter that depends on the overall performance recorded, and median and interquartile values were computed to perform a group analysis. Median (interquartile) values of P significantly increased from 0.27 (0.21) at T0 to 0.55 (0.27) at T1 . This improvement was functionally validated by a significant increase of the Melbourne Assessment of Unilateral Upper Limb Function. The parameter described here was able to show variations in performance over time and enabled a quantitative evaluation of motion abilities in a way that is reliable with respect to a well-known clinical scale.

The changing practice of transurethral resection of the prostate.

PubMed

Young, M J; Elmussareh, M; Morrison, T; Wilson, J R

2018-04-01

Introduction Transurethral resection of the prostate (TURP) is considered the gold standard surgical treatment for lower urinary tract symptoms (LUTS) secondary to benign prostatic hyperplasia. The number of TURPs performed has declined significantly over the last three decades owing to pharmaceutical therapy. TURP data from a single institution for the years 1990, 2000 and 2010 were compared to assess the difference in performance. Methods A retrospective analysis was undertaken of all patients who underwent TURP between January and December 2010. These findings were compared with historical data for the years 1990 and 2000: 100 sets of case notes were selected randomly from each of these years. Results The number of TURPs performed fell from 326 in 1990 to 113 in 2010. The mean age of patients increased from 70.6 years to 74.0 years. There was also a significant increase in the mean ASA grade from 1.9 to 2.3. The most common indication for TURP shifted from LUTS to acute urinary retention. No significant change in operating time was observed. The mean resection weight remained constant (22.95g in 1990, 22.55g in 2000, 20.76g in 2010). A reduction in transfusion rates was observed but there were higher rates of secondary haematuria and bladder neck stenosis. There was an increase from 2% to 11.5% of patients with long-term failure to void following TURP. Conclusions The number of TURPs performed continues to decline, which could lead to potential training issues. Urinary retention is still by far the most common indication. However, there has been a significant rise in the percentage of men presenting for TURP with high pressure chronic retention. The number of patients with bladder dysfunction who either have persistent storage LUTS or eventually require long-term catheterisation or intermittent self-catheterisation has increased markedly, which raises the question of what the long-term real life impact of medical therapy is on men with LUTS secondary to benign prostatic hyperplasia who eventually require surgery.

An eight-week golf-specific exercise program improves physical characteristics, swing mechanics, and golf performance in recreational golfers.

PubMed

Lephart, Scott M; Smoliga, James M; Myers, Joseph B; Sell, Timothy C; Tsai, Yung-Shen

2007-08-01

The purpose of this study was to determine the effects of an 8-week golf-specific exercise program on physical characteristics, swing mechanics, and golf performance. Fifteen trained male golfers (47.2 +/- 11.4 years, 178.8 +/- 5.8 cm, 86.7 +/- 9.0 kg, and 12.1 +/- 6.4 U.S. Golf Association handicap) were recruited. Trained golfers was defined operationally as golfers who play a round of golf at least 2-3 times per week and practice at the driving range at least 2-3 times per week during the regular golf season. Subjects performed a golf-specific conditioning program 3-4 times per week for 8 weeks during the off-season in order to enhance physical characteristics. Pre- and posttraining testing of participants included assessments of strength (torso, shoulder, and hip), flexibility, balance, swing mechanics, and golf performance. Following training, torso rotational strength and hip abduction strength were improved significantly (p < 0.05). Torso, shoulder, and hip flexibility improved significantly in all flexibility measurements taken (p < 0.05). Balance was improved significantly in 3 of 12 measurements, with the remainder of the variables demonstrating a nonsignificant trend for improvement. The magnitude of upper-torso axial rotation was decreased at the acceleration (p = 0.015) and impact points (p =0.043), and the magnitude of pelvis axial rotation was decreased at the top (p = 0.031) and acceleration points (p = 0.036). Upper-torso axial rotational velocity was increased significantly at the acceleration point of the golf swing (p = 0.009). Subjects increased average club velocity (p = 0.001), ball velocity (p = 0.001), carry distance (p = 0.001), and total distance (p = 0.001). These results indicate that a golf-specific exercise program improves strength, flexibility, and balance in golfers. These improvements result in increased upper-torso axial rotational velocity, which results in increased club head velocity, ball velocity, and driving distance.

Novel analysis of 4DCT imaging quantifies progressive increases in anatomic dead space during mechanical ventilation in mice.

PubMed

Kim, Elizabeth H; Preissner, Melissa; Carnibella, Richard P; Samarage, Chaminda R; Bennett, Ellen; Diniz, Marcio A; Fouras, Andreas; Zosky, Graeme R; Jones, Heather D

2017-09-01

Increased dead space is an important prognostic marker in early acute respiratory distress syndrome (ARDS) that correlates with mortality. The cause of increased dead space in ARDS has largely been attributed to increased alveolar dead space due to ventilation/perfusion mismatching and shunt. We sought to determine whether anatomic dead space also increases in response to mechanical ventilation. Mice received intratracheal lipopolysaccharide (LPS) or saline and mechanical ventilation (MV). Four-dimensional computed tomography (4DCT) scans were performed at onset of MV and after 5 h of MV. Detailed measurements of airway volumes and lung tidal volumes were performed using image analysis software. The forced oscillation technique was used to obtain measures of airway resistance, tissue damping, and tissue elastance. The ratio of airway volumes to total tidal volume increased significantly in response to 5 h of mechanical ventilation, regardless of LPS exposure, and airways demonstrated significant variation in volumes over the respiratory cycle. These findings were associated with an increase in tissue elastance (decreased lung compliance) but without changes in tidal volumes. Airway volumes increased over time with exposure to mechanical ventilation without a concomitant increase in tidal volumes. These findings suggest that anatomic dead space fraction increases progressively with exposure to positive pressure ventilation and may represent a pathological process. NEW & NOTEWORTHY We demonstrate that anatomic dead space ventilation increases significantly over time in mice in response to mechanical ventilation. The novel functional lung-imaging techniques applied here yield sensitive measures of airway volumes that may have wide applications. Copyright © 2017 the American Physiological Society.

The Effects of a Sport-Specific Maximal Strength and Conditioning Training on Critical Velocity, Anaerobic Running Distance, and 5-km Race Performance.

PubMed

Karsten, Bettina; Stevens, Liesbeth; Colpus, Mark; Larumbe-Zabala, Eneko; Naclerio, Fernando

2016-01-01

To investigate the effects of a sport-specific maximal 6-wk strength and conditioning program on critical velocity (CV), anaerobic running distance (ARD), and 5-km time-trial performance (TT). 16 moderately trained recreational endurance runners were tested for CV, ARD, and TT performances on 3 separate occasions (baseline, midstudy, and poststudy). Participants were randomly allocated into a strength and conditioning group (S&C; n = 8) and a comparison endurance-training-only group (EO; n = 8). During the first phase of the study (6 wk), the S&C group performed concurrent maximal strength and endurance training, while the EO group performed endurance-only training. After the retest of all variables (midstudy), both groups subsequently, during phase 2, performed another 6 wk of endurance-only training that was followed by poststudy tests. No significant change for CV was identified in either group. The S&C group demonstrated a significant decrease for ARD values after phases 1 and 2 of the study. TT performances were significantly different in the S&C group after the intervention, with a performance improvement of 3.62%. This performance increase returned close to baseline after the 6-wk endurance-only training. Combining a 6-wk resistance-training program with endurance training significantly improves 5-km TT performance. Removing strength training results in some loss of those performance improvements.

Influence of compressive gear on powerlifting performance: role of blood flow restriction training.

PubMed

Godawa, Travis M; Credeur, Daniel P; Welsch, Michael A

2012-05-01

This study investigated the effects of powerlifting gear on training volume and performance, defined by the squat, bench press, and deadlift. Eighteen powerlifters (18-26 years) were randomized into either a group that trained and competed using compressive gear (CG) or without the gear (NON). Training volume, volume progression, and powerlifting performance were assessed before and after 10 weeks of training. Training volume increased in the first 4 weeks for both groups. Volume lifted for squat and the totals were greater in the CG. There was an increase in squat (19.05 ± 30.97 lb, p = 0.02), deadlift (19.05 ± 21.17 lb, p = 0.001), and the total score (44.00 ± 60.44 lb, p = 0.005) for both the groups. The improvements in squat (CG = 33.85 vs. NON = 5.74, p = 0.07) and totals (CG = 66.59 vs. NON = 23.67, p = 0.15) were greater in the CG. Both groups showed a significant and similar increase in the Wilks scores (+13.54 points, p = 0.03). There was a trend toward greater volume progression in those wearing CG during the initial stages of training. Both the groups significantly improved performance for the squat, and deadlift, and had higher totals, and Wilks scores, indicating significant strength gains. The greater magnitude of improvements in the squat and totals for the CG lifters suggests an ergogenic potential of training with powerlifting gear.

Modification of Ni-Rich FCG NMC and NCA Cathodes by Atomic Layer Deposition: Preventing Surface Phase Transitions for High-Voltage Lithium-Ion Batteries

NASA Astrophysics Data System (ADS)

Mohanty, Debasish; Dahlberg, Kevin; King, David M.; David, Lamuel A.; Sefat, Athena S.; Wood, David L.; Daniel, Claus; Dhar, Subhash; Mahajan, Vishal; Lee, Myongjai; Albano, Fabio

2016-05-01

The energy density of current lithium-ion batteries (LIBs) based on layered LiMO2 cathodes (M = Ni, Mn, Co: NMC; M = Ni, Co, Al: NCA) needs to be improved significantly in order to compete with internal combustion engines and allow for widespread implementation of electric vehicles (EVs). In this report, we show that atomic layer deposition (ALD) of titania (TiO2) and alumina (Al2O3) on Ni-rich FCG NMC and NCA active material particles could substantially improve LIB performance and allow for increased upper cutoff voltage (UCV) during charging, which delivers significantly increased specific energy utilization. Our results show that Al2O3 coating improved the NMC cycling performance by 40% and the NCA cycling performance by 34% at 1 C/-1 C with respectively 4.35 V and 4.4 V UCV in 2 Ah pouch cells. High resolution TEM/SAED structural characterization revealed that Al2O3 coatings prevented surface-initiated layered-to-spinel phase transitions in coated materials which were prevalent in uncoated materials. EIS confirmed that Al2O3-coated materials had significantly lower increase in the charge transfer component of impedance during cycling. The ability to mitigate degradation mechanisms for Ni-rich NMC and NCA illustrated in this report provides insight into a method to enable the performance of high-voltage LIBs.

Modification of Ni-Rich FCG NMC and NCA Cathodes by Atomic Layer Deposition: Preventing Surface Phase Transitions for High-Voltage Lithium-Ion Batteries

PubMed Central

Mohanty, Debasish; Dahlberg, Kevin; King, David M.; David, Lamuel A.; Sefat, Athena S.; Wood, David L.; Daniel, Claus; Dhar, Subhash; Mahajan, Vishal; Lee, Myongjai; Albano, Fabio

2016-01-01

The energy density of current lithium-ion batteries (LIBs) based on layered LiMO2 cathodes (M = Ni, Mn, Co: NMC; M = Ni, Co, Al: NCA) needs to be improved significantly in order to compete with internal combustion engines and allow for widespread implementation of electric vehicles (EVs). In this report, we show that atomic layer deposition (ALD) of titania (TiO2) and alumina (Al2O3) on Ni-rich FCG NMC and NCA active material particles could substantially improve LIB performance and allow for increased upper cutoff voltage (UCV) during charging, which delivers significantly increased specific energy utilization. Our results show that Al2O3 coating improved the NMC cycling performance by 40% and the NCA cycling performance by 34% at 1 C/−1 C with respectively 4.35 V and 4.4 V UCV in 2 Ah pouch cells. High resolution TEM/SAED structural characterization revealed that Al2O3 coatings prevented surface-initiated layered-to-spinel phase transitions in coated materials which were prevalent in uncoated materials. EIS confirmed that Al2O3-coated materials had significantly lower increase in the charge transfer component of impedance during cycling. The ability to mitigate degradation mechanisms for Ni-rich NMC and NCA illustrated in this report provides insight into a method to enable the performance of high-voltage LIBs. PMID:27226071

Modification of Ni-Rich FCG NMC and NCA Cathodes by Atomic Layer Deposition: Preventing Surface Phase Transitions for High-Voltage Lithium-Ion Batteries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mohanty, Debasish; Dahlberg, Kevin; King, David M.

2016-05-26

The energy density of current lithium-ion batteries (LIBs) based on layered LiMO 2 cathodes (M=Ni, Mn, Co: NMC; M=Ni, Co, Al: NCA) needs to be improved significantly in order to compete with internal combustion engines and allow for widespread implementation of electric vehicles (EVs). In this report, we show that atomic layer deposition (ALD) of titania (TiO 2) and alumina (Al 2O 3) on Ni-rich FCG NMC and NCA active material particles could substantially improve LIB performance and allow for increased upper cutoff voltage (UCV) during charging, which delivers significantly increased specific energy utilization. Our results show that Al2O3 coatingmore » improved the NMC cycling performance by 40% and the NCA cycling performance by 34% at 1C/₋1C with respectively 4.35V and 4.4V UCV in 2Ah pouch cells. High resolution TEM/SAED structural characterization revealed that Al 2O 3 coatings prevented surface-initiated layered-to-spinel phase transitions in coated materials which were prevalent in uncoated materials. Lastly, EIS confirmed that Al 2O 3-coated materials had significantly lower increase in the charge transfer component of impedance during cycling. In conclusion, the ability to mitigate degradation mechanisms for Ni-rich NMC and NCA illustrated in this report provides insight into a method to enable the performance of high-voltage LIBs.« less

Neurophysiological Correlates of Attentional Fluctuation in Attention-Deficit/Hyperactivity Disorder.

PubMed

Cheung, Celeste H M; McLoughlin, Gráinne; Brandeis, Daniel; Banaschewski, Tobias; Asherson, Philip; Kuntsi, Jonna

2017-05-01

Cognitive performance in attention-deficit/hyperactivity disorder (ADHD) is characterised, in part, by frequent fluctuations in response speed, resulting in high reaction time variability (RTV). RTV captures a large proportion of the genetic risk in ADHD but, importantly, is malleable, improving significantly in a fast-paced, rewarded task condition. Using the temporal precision offered by event-related potentials (ERPs), we aimed to examine the neurophysiological measures of attention allocation (P3 amplitudes) and preparation (contingent negative variation, CNV), and their associations with the fluctuating RT performance and its improvement in ADHD. 93 participants with ADHD and 174 controls completed the baseline and fast-incentive conditions of a four-choice reaction time task, while EEG was simultaneously recorded. Compared to controls, individuals with ADHD showed both increased RTV and reduced P3 amplitudes during performance on the RT task. In the participants with ADHD, attenuated P3 amplitudes were significantly associated with high RTV, and the increase in P3 amplitudes from a slow baseline to a fast-paced, rewarded condition was significantly associated with the RTV decrease. Yet, the individuals with ADHD did not show the same increase in CNV from baseline to fast-incentive condition as observed in controls. ADHD is associated both with a neurophysiological impairment of attention allocation (P3 amplitudes) and an inability to adjust the preparatory state (CNV) in a changed context. Our findings suggest that both neurophysiological and cognitive performance measures of attention are malleable in ADHD, which are potential targets for non-pharmacological interventions.

Comparative Effects of Teriparatide and Risedronate in Glucocorticoid-Induced Osteoporosis in Men: 18-Month Results of the EuroGIOPs Trial

PubMed Central

Glüer, Claus-C; Marin, Fernando; Ringe, Johann D; Hawkins, Federico; Möricke, Rüdiger; Papaioannu, Nikolaos; Farahmand, Parvis; Minisola, Salvatore; Martínez, Guillermo; Nolla, Joan M; Niedhart, Christopher; Guañabens, Nuria; Nuti, Ranuccio; Martín-Mola, Emilio; Thomasius, Friederike; Kapetanos, Georgios; Peña, Jaime; Graeff, Christian; Petto, Helmut; Sanz, Beatriz; Reisinger, Andreas; Zysset, Philippe K

2013-01-01

Data on treatment of glucocorticoid-induced osteoporosis (GIO) in men are scarce. We performed a randomized, open-label trial in men who have taken glucocorticoids (GC) for ≥3 months, and had an areal bone mineral density (aBMD) T-score ≤ –1.5 standard deviations. Subjects received 20 μg/d teriparatide (n = 45) or 35 mg/week risedronate (n = 47) for 18 months. Primary objective was to compare lumbar spine (L1–L3) BMD measured by quantitative computed tomography (QCT). Secondary outcomes included BMD and microstructure measured by high-resolution QCT (HRQCT) at the 12th thoracic vertebra, biomechanical effects for axial compression, anterior bending, and axial torsion evaluated by finite element (FE) analysis from HRQCT data, aBMD by dual X-ray absorptiometry, biochemical markers, and safety. Computed tomography scans were performed at 0, 6, and 18 months. A mixed model repeated measures analysis was performed to compare changes from baseline between groups. Mean age was 56.3 years. Median GC dose and duration were 8.8 mg/d and 6.4 years, respectively; 39.1% of subjects had a prevalent fracture, and 32.6% received prior bisphosphonate treatment. At 18 months, trabecular BMD had significantly increased for both treatments, with significantly greater increases with teriparatide (16.3% versus 3.8%; p = 0.004). HRQCT trabecular and cortical variables significantly increased for both treatments with significantly larger improvements for teriparatide for integral and trabecular BMD and bone surface to volume ratio (BS/BV) as a microstructural measure. Vertebral strength increases at 18 months were significant in both groups (teriparatide: 26.0% to 34.0%; risedronate: 4.2% to 6.7%), with significantly higher increases in the teriparatide group for all loading modes (0.005 < p < 0.015). Adverse events were similar between groups. None of the patients on teriparatide but five (10.6%) on risedronate developed new clinical fractures (p = 0.056). In conclusion, in this 18-month trial in men with GIO, teriparatide showed larger improvements in spinal BMD, microstructure, and FE-derived strength than risedronate. PMID:23322362

In vivo evaluation of biomechanical properties in the patellofemoral joint after matrix-associated autologous chondrocyte transplantation by means of quantitative T2 MRI.

PubMed

Pachowsky, M L; Trattnig, S; Wondrasch, B; Apprich, S; Marlovits, S; Mauerer, A; Welsch, Goetz H; Blanke, M

2014-06-01

To determine in vivo biomechanical properties of articular cartilage and cartilage repair tissue of the patella, using biochemical MRI by means of quantitative T2 mapping. Twenty MR scans were achieved at 3T MRI, using a new 8-channel multi-function coil allowing controlled bending of the knee. Multi-echo spin-echo T2 mapping was prepared in healthy volunteers and in age- and sex-matched patients after matrix-associated autologous chondrocyte transplantation (MACT) of the patella. MRI was performed at 0° and 45° of flexion of the knee after 0 min and after 1 h. A semi-automatic region-of-interest analysis was performed for the whole patella cartilage. To allow stratification with regard to the anatomical (collagen) structure, further subregional analysis was carried out (deep-middle-superficial cartilage layer). Statistical analysis of variance was performed. During 0° flexion (decompression), full-thickness T2 values showed no significant difference between volunteers (43 ms) and patients (41 ms). Stratification was more pronounced for healthy cartilage compared to cartilage repair tissue. During 45° flexion (compression), full-thickness T2 values within volunteers were significantly increased (54 ms) compared to patients (44 ms) (p < 0.001). Again, stratification was more pronounced in volunteers compared to patients. The volunteer group showed no significant increase in T2 values measured in straight position and in bended position. There was no significant difference between the 0- and the 60-min MRI examination. T2 values in the patient group increased between the 0- and the 60-min examination. However, the increase was only significant in the superior cartilage layer of the straight position (p = 0.021). During compression (at 45° flexion), healthy patellar cartilage showed a significant increase in T2-values, indicating adaptations of water content and collagen fibril orientation to mechanical load. This could not be observed within the patella cartilage after cartilage repair (MACT) of the patella, most obvious due to a lack of biomechanical adjustment. III.

The impact of mirrors on body image and performance in high and low performing female ballet students.

PubMed

Radell, Sally A; Adame, Daniel D; Cole, Steven P; Blumenkehl, Nicole J

2011-09-01

This study assesses the effect of mirrors on body image and performance in high and low performing female collegiate ballet students. Twenty-three females enrolled in a beginning ballet class were taught using mirrors, and a second group of 23 beginning females were taught without mirrors. All participants completed the Cash 69-item Body Self-Relations Questionnaire during the first and last class of a 14-week semester. They were videotaped performing in the studio during the fifth and fourteenth weeks. Two ballet teachers independently viewed the videotapes to evaluate the dancers' rhythmic accuracy, ease and flow of movement, and mastery of steps and alignment, and rated the students' skill level on a 1-5 scale. For analysis purposes, students whose scores averaged three or higher were categorized as "high performers," and those who averaged less than three were "low performers." Two (mirror, non-mirror) by two (high performance, low performance) by two (pre-test, post-test) repeated measures ANOVAs were used to test class differences over the course of the semester. There were significant 3-way interactions for overweight preoccupation (p < 0.01) and body-areas satisfaction (p < 0.05). Low performers increased in overweight preoccupation in the non-mirror class while decreasing in the mirror class. High performers significantly increased in satisfaction for most areas of their body in the non-mirror class, while there were smaller increases for both low and high performers in the mirror class. It is concluded that while use of the mirror has some benefits in training, higher performing dancers feel better about their body image when they do not use the mirror. Lower performers who use the mirror worry less about their weight; those who do not use the mirror worry more. The mirror may provide feedback that helps low performing dancers feel more comfortable with their weight.

Seagrass ecophysiological performance under ocean warming and acidification.

PubMed

Repolho, Tiago; Duarte, Bernardo; Dionísio, Gisela; Paula, José Ricardo; Lopes, Ana R; Rosa, Inês C; Grilo, Tiago F; Caçador, Isabel; Calado, Ricardo; Rosa, Rui

2017-02-01

Seagrasses play an essential ecological role within coastal habitats and their worldwide population decline has been linked to different types of anthropogenic forces. We investigated, for the first time, the combined effects of future ocean warming and acidification on fundamental biological processes of Zostera noltii, including shoot density, leaf coloration, photophysiology (electron transport rate, ETR; maximum PSII quantum yield, F v /F m ) and photosynthetic pigments. Shoot density was severely affected under warming conditions, with a concomitant increase in the frequency of brownish colored leaves (seagrass die-off). Warming was responsible for a significant decrease in ETR and F v /F m (particularly under control pH conditions), while promoting the highest ETR variability (among experimental treatments). Warming also elicited a significant increase in pheophytin and carotenoid levels, alongside an increase in carotenoid/chlorophyll ratio and De-Epoxidation State (DES). Acidification significantly affected photosynthetic pigments content (antheraxanthin, β-carotene, violaxanthin and zeaxanthin), with a significant decrease being recorded under the warming scenario. No significant interaction between ocean acidification and warming was observed. Our findings suggest that future ocean warming will be a foremost determinant stressor influencing Z. noltii survival and physiological performance. Additionally, acidification conditions to occur in the future will be unable to counteract deleterious effects posed by ocean warming.

Seagrass ecophysiological performance under ocean warming and acidification

PubMed Central

Repolho, Tiago; Duarte, Bernardo; Dionísio, Gisela; Paula, José Ricardo; Lopes, Ana R.; Rosa, Inês C.; Grilo, Tiago F.; Caçador, Isabel; Calado, Ricardo; Rosa, Rui

2017-01-01

Seagrasses play an essential ecological role within coastal habitats and their worldwide population decline has been linked to different types of anthropogenic forces. We investigated, for the first time, the combined effects of future ocean warming and acidification on fundamental biological processes of Zostera noltii, including shoot density, leaf coloration, photophysiology (electron transport rate, ETR; maximum PSII quantum yield, Fv/Fm) and photosynthetic pigments. Shoot density was severely affected under warming conditions, with a concomitant increase in the frequency of brownish colored leaves (seagrass die-off). Warming was responsible for a significant decrease in ETR and Fv/Fm (particularly under control pH conditions), while promoting the highest ETR variability (among experimental treatments). Warming also elicited a significant increase in pheophytin and carotenoid levels, alongside an increase in carotenoid/chlorophyll ratio and De-Epoxidation State (DES). Acidification significantly affected photosynthetic pigments content (antheraxanthin, β-carotene, violaxanthin and zeaxanthin), with a significant decrease being recorded under the warming scenario. No significant interaction between ocean acidification and warming was observed. Our findings suggest that future ocean warming will be a foremost determinant stressor influencing Z. noltii survival and physiological performance. Additionally, acidification conditions to occur in the future will be unable to counteract deleterious effects posed by ocean warming. PMID:28145531

Intranasal insulin treatment of an experimental model of moderate traumatic brain injury.

PubMed

Brabazon, Fiona; Wilson, Colin M; Jaiswal, Shalini; Reed, John; Frey, William H; Byrnes, Kimberly R

2017-09-01

Traumatic brain injury (TBI) results in learning and memory dysfunction. Cognitive deficits result from cellular and metabolic dysfunction after injury, including decreased cerebral glucose uptake and inflammation. This study assessed the ability of intranasal insulin to increase cerebral glucose uptake after injury, reduce lesion volume, improve memory and learning function and reduce inflammation. Adult male rats received a controlled cortical impact (CCI) injury followed by intranasal insulin or saline treatment daily for 14 days. PET imaging of [18F]-FDG uptake was performed at baseline and at 48 h and 10 days post-injury and MRI on days three and nine post injury. Motor function was tested with the beam walking test. Memory function was assessed with Morris water maze. Intranasal insulin after CCI significantly improved several outcomes compared to saline. Insulin-treated animals performed better on beam walk and demonstrated significantly improved memory. A significant increase in [18F]-FDG uptake was observed in the hippocampus. Intranasal insulin also resulted in a significant decrease in hippocampus lesion volume and significantly less microglial immunolabeling in the hippocampus. These data show that intranasal insulin improves memory, increases cerebral glucose uptake and decreases neuroinflammation and hippocampal lesion volume, and may therefore be a viable therapy for TBI.

Stroop effects in Alzheimer's disease: selective attention speed of processing, or color-naming? A meta-analysis.

PubMed

Ben-David, Boaz M; Tewari, Anita; Shakuf, Vered; Van Lieshout, Pascal H H M

2014-01-01

Selective attention, an essential part of daily activity, is often impaired in people with Alzheimer's disease (AD). Usually, it is measured by the color-word Stroop test. However, there is no universal agreement whether performance on the Stroop task changes significantly in AD patients; or if so, whether an increase in Stroop effects reflects a decrease in selective attention, a slowing in generalized speed of processing (SOP), or is the result of degraded color-vision. The current study investigated the impact of AD on Stroop performance and its potential sources in a meta-analysis and mathematical modeling of 18 studies, comparing 637 AD patients with 977 healthy age-matched participants. We found a significant increase in Stroop effects for AD patients, across studies. This AD-related change was associated with a slowing in SOP. However, after correcting for a bias in the distribution of latencies, SOP could only explain a moderate portion of the total variance (25%). Moreover, we found strong evidence for an AD-related increase in the latency difference between naming the font-color and reading color-neutral stimuli (r2 = 0.98). This increase in the dimensional imbalance between color-naming and word-reading was found to explain a significant portion of the AD-related increase in Stroop effects (r2 = 0.87), hinting on a possible sensory source. In conclusion, our analysis highlights the importance of controlling for sensory degradation and SOP when testing cognitive performance and, specifically, selective attention in AD patients. We also suggest possible measures and tools to better test for selective attention in AD.

Acrosin activity is a suitable indicator of boar semen preservation at 17 °C when increasing environmental temperature and radiation.

PubMed

Pinart, E; Yeste, M; Puigmulé, M; Barrera, X; Bonet, S

2013-08-01

The effect of increasing environmental temperature and radiation on the sperm quality and the field fertility of refrigerated seminal doses from AI boars (N = 30) was analyzed throughout four experimental months (from March through June). In each experimental month, analyses of sperm quality were performed at days 0, 1, 3, 5, 7, and 9 of refrigeration of seminal doses; pregnancy rate and litter size were evaluated using double monospermic inseminations of multiparous female animals using seminal doses at Days 1 to 2 and Days 3 to 4 of refrigeration. Sperm quality was assessed from the evaluation of conventional parameters of sperm concentration, sperm motility, sperm morphology, and sperm viability, and capacitation parameters of membrane lipid disorder, intracellular calcium content, and acrosin activity. Results showed that sperm quality of boar seminal doses was negatively affected by increasing temperature and radiation, which resulted in significantly decreased sperm motility and viability, acrosin activity, pregnancy rate, and litter size, and significantly increased intracellular calcium levels in the trials performed in June. In any experimental month, aging of refrigerated doses was associated with the progressive increase of intracellular calcium levels and inactivation of acrosin, that began from Day 5 of storage in the trials performed in March and April, from Day 3 in those of May, and from Day 0 in those of June. Among the sperm parameters analyzed, only acrosin activity exhibited a clearly differentiated pattern in association with increasing temperature and radiation, and a significant correlation with pregnancy rate and litter size. These results highlighted the potential role of acrosin activity as an indicator of boar sperm preservation at 17 °C in boars. Copyright © 2013 Elsevier Inc. All rights reserved.

The Applications of Mindfulness with Students of Secondary School: Results on the Academic Performance, Self-concept and Anxiety

NASA Astrophysics Data System (ADS)

Franco, Clemente; Mañas, Israel; Cangas, Adolfo J.; Gallego, José

The aim of the present research is to verify the impact of a mindfulness programme on the levels academic performance, self-concept and anxiety, of a group of students in Year 1 at secondary school. The statistical analyses carried out on the variables studied showed significant differences in favour of the experimental group with regard to the control group in all the variables analysed. In the experimental group we can observe a significant increase of academic performance as well as an improvement in all the self-concept dimensions, and a significant decrease in anxiety states and traits. The importance and usefulness of mindfulness techniques in the educative system is discussed.

Organic Selenium, Probiotics, and Prebiotics Effects on Growth, Blood Biochemistry, and Carcass Traits of Growing Rabbits During Summer and Winter Seasons.

PubMed

Ayyat, Mohamed S; Al-Sagheer, Adham A; Abd El-Latif, Khaled M; Khalil, Bakry A

2018-03-07

The effect of organic selenium, prebiotics, or probiotics on productive performances, blood biochemistry, and carcass characteristics of growing rabbits was studied throughout summer and winter seasons. In an 8-week feeding trial, a total of 100 New Zealand White rabbits were randomly distributed to 10 groups. Two seasons (winter and summer) and five diets fortified with 0 (control), 0.03 mg selenium, 3 g Bio-Mos®, 1 g Bactocell® (1 × 10 10  CFU) or 3 g yeast/kg diet were used in 2 × 5 factorial design. Results indicated that growth performance, feed intake (FI), and blood components (red blood cells [RBCs], serum total protein [TP], globulin [GLOB], albumin [ALB]) decreased significantly in rabbits reared during summer than in those during winter. In contrast, white blood cells, urea-N, creatinine, alanine transaminase [ALT], and aspartate transaminase [AST] increased significantly in summer. However, growth performance indices, FI, blood hemoglobin, RBCs, TP, ALB, and GLOB increased significantly in rabbits when fed the tested feed additives. The respiration rate, rectal temperature, and heart rate of the animals were significantly decreased with all feed additives. Adjusted weight of carcass, liver, kidney fat, and carcass cuts were not affected by feed additives. Final margin and margin efficiency increased in rabbit fed diets supplemented with feed additives than those fed the basal diet without any supplementation. Results of the current study concluded that a supplementation of rabbit diets with organic selenium, probiotics, and prebiotics can promote rabbit performance during mild weather and also alleviate the adverse impact of heat stress during summer season.

The effects of caffeine ingestion on the reaction time and short-term maximal performance after 36 h of sleep deprivation.

PubMed

Souissi, Makram; Chtourou, Hamdi; Abedelmalek, Salma; Ghozlane, Imen Ben; Sahnoun, Zouhair

2014-05-28

The aim of the present study was to investigate the effects of caffeine ingestion on cognitive and physical performances after 36h of sleep deprivation. In randomized order, thirteen healthy male physical education students (age: 21.1±1.1years, body mass: 77.1±7.2kg, height: 1.77±0.06m) completed four test sessions at 18:00h: after placebo or 5mg·kg(-1) of caffeine ingestion during a baseline night (RN) (bed time: from 22:30h to 07:00h) or a night of 36h of sleep deprivation (TSD). During each test session, participants performed the squat jump (SJ), the reaction time, and the 30-s Wingate tests (i.e., for the measurement of the peak (PP) and mean (MP) powers and the fatigue index (FI)). The results showed that PP and MP decreased and FI increased during the TSD compared to RN in the placebo condition (p<0.001). The caffeine ingestion improved PP after TSD compared to RN (p<0.001). SJ decreased significantly after the TSD compared to RN after both placebo and caffeine ingestions (p<0.001). However, SJ increased significantly after caffeine ingestion during RN and TSD (p<0.001). The reaction time increased significantly after TSD compared to RN (p<0.001). However, the reaction time decreased significantly after the caffeine ingestion only during the TSD (p<0.001). Therefore, caffeine is an effective strategy to counteract the effect of 36h of sleep loss on physical and cognitive performances. Copyright © 2014 Elsevier Inc. All rights reserved.

Effects of Low- vs. High-Load Resistance Training on Muscle Strength and Hypertrophy in Well-Trained Men.

PubMed

Schoenfeld, Brad J; Peterson, Mark D; Ogborn, Dan; Contreras, Bret; Sonmez, Gul T

2015-10-01

The purpose of this study was to compare the effect of low- versus high-load resistance training (RT) on muscular adaptations in well-trained subjects. Eighteen young men experienced in RT were matched according to baseline strength and then randomly assigned to 1 of 2 experimental groups: a low-load RT routine (LL) where 25-35 repetitions were performed per set per exercise (n = 9) or a high-load RT routine (HL) where 8-12 repetitions were performed per set per exercise (n = 9). During each session, subjects in both groups performed 3 sets of 7 different exercises representing all major muscles. Training was performed 3 times per week on nonconsecutive days, for a total of 8 weeks. Both HL and LL conditions produced significant increases in thickness of the elbow flexors (5.3 vs. 8.6%, respectively), elbow extensors (6.0 vs. 5.2%, respectively), and quadriceps femoris (9.3 vs. 9.5%, respectively), with no significant differences noted between groups. Improvements in back squat strength were significantly greater for HL compared with LL (19.6 vs. 8.8%, respectively), and there was a trend for greater increases in 1 repetition maximum (1RM) bench press (6.5 vs. 2.0%, respectively). Upper body muscle endurance (assessed by the bench press at 50% 1RM to failure) improved to a greater extent in LL compared with HL (16.6 vs. -1.2%, respectively). These findings indicate that both HL and LL training to failure can elicit significant increases in muscle hypertrophy among well-trained young men; however, HL training is superior for maximizing strength adaptations.

Sake Protein Supplementation Affects Exercise Performance and Biochemical Profiles in Power-Exercise-Trained Mice

PubMed Central

Chen, Yi-Ming; Lin, Che-Li; Wei, Li; Hsu, Yi-Ju; Chen, Kuan-Neng; Huang, Chi-Chang; Kao, Chin-Hsung

2016-01-01

Exercise and fitness training programs have attracted the public’s attention in recent years. Sports nutrition supplementation is an important issue in the global sports market. Purpose: In this study, we designed a power exercise training (PET) program with a mouse model based on a strength and conditional training protocol for humans. We tested the effect of supplementation with functional branched-chain amino acid (BCAA)-rich sake protein (SP) to determine whether the supplement had a synergistic effect during PET and enhanced athletic performance and resistance to fatigue. Methods: Male ICR mice were divided into three groups (n = 8 per group) for four-week treatment: sedentary controls with vehicle (SC), and PET and PET groups with SP supplementation (3.8 g/kg, PET + SP). Exercise performance was evaluated by forelimb grip strength and exhaustive swimming time as well as changes in body composition and anti-fatigue activity levels of serum lactate, ammonia, glucose, and creatine kinase (CK) after a 15-min swimming exercise. The biochemical parameters were measured at the end of the experiment. Results: four-week PET significantly increased grip strength and exhaustive swimming time and decreased epididymal fat pad (EFP) weight and area. Levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatinine, and uric acid (UA) were significantly increased. PET + SP supplementation significantly decreased serum lactate, ammonia and CK levels after the 15-min swimming exercise. The resting serum levels of AST, ALT, CREA and UA were all significantly decreased with PET + SP. Conclusion: The PET program could increase the exercise performance and modulate the body composition of mice. PET with SP conferred better anti-fatigue activity, improved biochemical profiles, and may be an effective ergogenic aid in strength training. PMID:26907336

Evaluating blood-brain barrier permeability in delayed cerebral infarction after aneurysmal subarachnoid hemorrhage.

PubMed

Ivanidze, J; Kesavabhotla, K; Kallas, O N; Mir, D; Baradaran, H; Gupta, A; Segal, A Z; Claassen, J; Sanelli, P C

2015-05-01

Patients with SAH are at increased risk of delayed infarction. Early detection and treatment of delayed infarction remain challenging. We assessed blood-brain barrier permeability, measured as permeability surface area product, by using CTP in patients with SAH with delayed infarction. We performed a retrospective study of patients with SAH with delayed infarction on follow-up NCCT. CTP was performed before the development of delayed infarction. CTP data were postprocessed into permeability surface area product, CBF, and MTT maps. Coregistration was performed to align the infarcted region on the follow-up NCCT with the corresponding location on the CTP maps obtained before infarction. Permeability surface area product, CBF, and MTT values were then obtained in the location of the subsequent infarction. The contralateral noninfarcted region was compared with the affected side in each patient. Wilcoxon signed rank tests were performed to determine statistical significance. Clinical data were collected at the time of CTP and at the time of follow-up NCCT. Twenty-one patients with SAH were included in the study. There was a statistically significant increase in permeability surface area product in the regions of subsequent infarction compared with the contralateral control regions (P < .0001). However, CBF and MTT values were not significantly different in these 2 regions. Subsequent follow-up NCCT demonstrated new delayed infarction in all 21 patients, at which time 38% of patients had new focal neurologic deficits. Our study reveals a statistically significant increase in permeability surface area product preceding delayed infarction in patients with SAH. Further investigation of early permeability changes in SAH may provide new insights into the prediction of delayed infarction. © 2015 by American Journal of Neuroradiology.

Sake Protein Supplementation Affects Exercise Performance and Biochemical Profiles in Power-Exercise-Trained Mice.

PubMed

Chen, Yi-Ming; Lin, Che-Li; Wei, Li; Hsu, Yi-Ju; Chen, Kuan-Neng; Huang, Chi-Chang; Kao, Chin-Hsung

2016-02-20

Exercise and fitness training programs have attracted the public's attention in recent years. Sports nutrition supplementation is an important issue in the global sports market. In this study, we designed a power exercise training (PET) program with a mouse model based on a strength and conditional training protocol for humans. We tested the effect of supplementation with functional branched-chain amino acid (BCAA)-rich sake protein (SP) to determine whether the supplement had a synergistic effect during PET and enhanced athletic performance and resistance to fatigue. Male ICR mice were divided into three groups (n = 8 per group) for four-week treatment: sedentary controls with vehicle (SC), and PET and PET groups with SP supplementation (3.8 g/kg, PET + SP). Exercise performance was evaluated by forelimb grip strength and exhaustive swimming time as well as changes in body composition and anti-fatigue activity levels of serum lactate, ammonia, glucose, and creatine kinase (CK) after a 15-min swimming exercise. The biochemical parameters were measured at the end of the experiment. four-week PET significantly increased grip strength and exhaustive swimming time and decreased epididymal fat pad (EFP) weight and area. Levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatinine, and uric acid (UA) were significantly increased. PET + SP supplementation significantly decreased serum lactate, ammonia and CK levels after the 15-min swimming exercise. The resting serum levels of AST, ALT, CREA and UA were all significantly decreased with PET + SP. The PET program could increase the exercise performance and modulate the body composition of mice. PET with SP conferred better anti-fatigue activity, improved biochemical profiles, and may be an effective ergogenic aid in strength training.

Due process model of procedural justice in performance appraisal: promotion versus termination scenarios.

PubMed

Kataoka, Heloneida C; Cole, Nina D; Flint, Douglas A

2006-12-01

In a laboratory study, 318 student participants (148 male, 169 female, and one who did not report sex; M age 25.0, SD = 6.0) in introductory organizational behavior classes responded to scenarios in which performance appraisal resulted in either employee promotion or termination. Each scenario had varying levels of three procedural justice criteria for performance appraisal. For both promotion and termination outcomes, analysis showed that, as the number of criteria increased, perceptions of procedural fairness increased. A comparison between the two outcomes showed that perceptions of fairness were significantly stronger for the promotion outcome than for termination.

Near-infrared spectroscopic study on the effects of chewing on short-term memory.

PubMed

Wada, Mayumi; Hoshi, Yoko; Iguchi, Yoshinobu; Kida, Ikuhiro

2011-12-01

Using near-infrared spectroscopy, we examined whether chewing gum improves performance in a short-term memory task - immediate recall of random eight-digit numbers - by assessing cerebral hemodynamic response in the prefrontal cortex. We found that the oxyhemoglobin concentration during and after chewing gum was higher than that before chewing; further, the concentration increased during the task, and this increase was reduced with chewing, although non-significantly. Chewing did not improve task performance. Therefore, chewing-induced hemodynamic responses were unrelated to the performance in short-term memory tasks. Copyright © 2011 Elsevier Ltd. All rights reserved.

The Effect of Autogenic Training on Self-Efficacy, Anxiety, and Performance on Nursing Student Simulation.

PubMed

Holland, Brian; Gosselin, Kevin; Mulcahy, Angela

The increased anxiety experienced by nursing students during simulations can serve as a significant barrier to learning. The use of anxiety-reducing techniques such as autogenic training (AT) can mitigate the negative effects of anxiety and improve the overall learning experience. The investigators in this study sought to understand the effect of AT on student performance and self-efficacy during simulation experiences. The use of AT was an effective technique to decrease anxiety and increase performance among nursing students during nursing simulations. Reducing anxiety during simulations can improve the student learning experience.

Demonstrated high performance of gas-filled rugby-shaped hohlraums on Omega

NASA Astrophysics Data System (ADS)

Philippe, F.; Tassin, V.; Depierreux, S.; Gauthier, P.; Masson-Laborde, P. E.; Monteil, M. C.; Seytor, P.; Villette, B.; Lasinski, B.; Park, H. S.; Ross, J. S.; Amendt, P.; Döppner, T.; Hinkel, D. E.; Wallace, R.; Williams, E.; Michel, P.; Frenje, J.; Gatu-Johnson, M.; Li, C. K.; Petrasso, R.; Glebov, V.; Sorce, C.; Stoeckl, C.; Nikroo, A.; Giraldez, E.

2014-07-01

A direct experimental comparison of rugby-shaped and cylindrical shaped gas-filled hohlraums on the Omega laser facility demonstrates that higher coupling and minimal backscatter can be achieved in the rugby geometry, leading to significantly enhanced implosion performance. A nearly 50% increase of x-ray drive is associated with earlier bangtime and increase of neutron production. The observed drive enhancement from rugby geometry in this study is almost twice stronger than in previously published results.

Effects of chemical equilibrium on turbine engine performance for various fuels and combustor temperatures

NASA Technical Reports Server (NTRS)

Tran, Donald H.; Snyder, Christopher A.

1992-01-01

A study was performed to quantify the differences in turbine engine performance with and without the chemical dissociation effects for various fuel types over a range of combustor temperatures. Both turbojet and turbofan engines were studied with hydrocarbon fuels and cryogenic, nonhydrocarbon fuels. Results of the study indicate that accuracy of engine performance decreases when nonhydrocarbon fuels are used, especially at high temperatures where chemical dissociation becomes more significant. For instance, the deviation in net thrust for liquid hydrogen fuel can become as high as 20 percent at 4160 R. This study reveals that computer central processing unit (CPU) time increases significantly when dissociation effects are included in the cycle analysis.

Effect of overtime work on cognitive function in automotive workers.

PubMed

Proctor, S P; White, R F; Robins, T G; Echeverria, D; Rocskay, A Z

1996-04-01

The present investigation examined whether increased overtime work predicts impairment in cognitive performance in the domains of attention, executive function, and mood. The behavioral and cognitive functions of 248 automotive workers were measured by a neurobehavioral test performance. Overtime, defined as number of hours worked greater than 8 h a day or greater than 5 d a week, was calculated from company payroll records for the week before the test day. The number of consecutive days worked before the test day was also determined. Cross-sectional data analysis by multiple linear regression, after adjustment for the effects of age, education, gender, alcohol intake, repeated grade in school, acute petroleum naphtha exposure, shift worked, job type, number of consecutive days worked before the test day, and number of hours worked on the test day before the testing, demonstrated that increased overtime was significantly associated with impaired performance on several tests of attention and executive function. Increased feelings of depression, fatigue, and confusion were also associated with increased overtime work. In addition significant interaction effects were observed for job type but not for naphtha exposure. The findings support the hypothesis that overtime work results in impaired cognitive performance in the areas of attention and executive function and that both overtime hours and the number of consecutive days worked prior to a test day affect mood.

Thinking Teacher Professional Learning Performatively: A Socio-Material Account

ERIC Educational Resources Information Center

Mulcahy, Dianne

2012-01-01

New socio-economic conditions have resulted in significant reconfiguration of professional learning in terms of the increasing integration of work into curriculum, pedagogy and inter-professional relationships. This article examines the significance of "more than human" dimensions for this learning, using resources provided by…

Cosmetic surgery growth and correlations with financial indices: a comparative study of the United Kingdom and United States from 2002-2011.

PubMed

Nassab, Reza; Harris, Paul

2013-05-01

Over the past 10 years, there has been significant fluctuation in the yearly growth rates for cosmetic surgery procedures in both the United States and the United Kingdom. The authors compare cosmetic surgical procedure rates in the United Kingdom and United States with the macroeconomic climate of each region to determine whether there is a direct relationship between cosmetic surgery rates and economic health. The authors analyzed annual cosmetic surgery statistics from the British Association of Aesthetic Plastic Surgeons and the American Society for Aesthetic Plastic Surgery for 2002-2011 against economic indices from both regions, including the gross domestic product (GDP), consumer prices indices (CPI), and stock market reports. There was a 285.9% increase in the United Kingdom and a 1.1% increase in the United States in the number of procedures performed between 2002 and 2011. There were significant positive correlations between the number of cosmetic procedures performed in the United Kingdom and both the GDP (r = 0.986, P < .01) and CPI (r = 0.955, P < .01). Analysis of the US growth rates failed to show a significant relationship with any indices. UK interest rates showed a significant negative correlation (r = -0.668, P < .05) with procedures performed, whereas US interest rates showed a significant positive correlation. Data from the United States and United Kingdom suggest 2 very different growth patterns in the number of cosmetic surgeries being performed as compared with the economy in each region. Economic indices are accurate indicators of numbers of procedures being performed in the United Kingdom, whereas rates in the United States seem independent of those factors.

Changes in selected physical, motor performance and anthropometric components of university-level rugby players after one microcycle of a combined rugby conditioning and plyometric training program.

PubMed

Pienaar, Cindy; Coetzee, Ben

2013-02-01

The purpose of this study was to determine the effects of a microcycle (4 weeks) combined rugby conditioning plyometric compared with a nonplyometric rugby conditioning program on selected physical and motor performance components and anthropometric measurements of university-level rugby players. Players (18.94 ± 0.40 years) were assigned to either a control (n = 16) or experimental group (n = 19) from the U/19 rugby teams of the North-West University (South Africa). Twenty-six direct and indirect anthropometric measurements were taken, and the players performed a battery of 5 physical and motor performance tests before and after a microcycle (4 week) combined rugby conditioning plyometric (experimental group) and a nonplyometric rugby conditioning program (control group). The dependent t-test results showed that the control group's upper-body explosive power decreased significantly, whereas the stature, skeletal mass, and femur breadth increased significantly from pre- to posttesting. The experimental group showed significant increases in wrist breadth, speed over 20 m, agility, and power and work measurements of the Wingate anaerobic test (WAnT). Despite these results, the independent t-test revealed that speed over 20 m, average power output at 20 seconds, relative work of the WAnT, and agility were the only components of the experimental group that improved significantly more than the control group. A microcycle combined rugby conditioning plyometric program therefore leads to significantly bigger changes in selected physical and motor performance components of university-level rugby players than a nonplyometric rugby conditioning program alone. Based on these findings, coaches and sport scientists should implement 3 weekly combined rugby conditioning plyometric programs in rugby players' training regimens to improve the players' speed, agility, and power.

Financial Analysis of Treating Periprosthetic Joint Infections at a Tertiary Referral Center.

PubMed

Waddell, Bradford S; Briski, David C; Meyer, Mark S; Ochsner, John L; Chimento, George F

2016-05-01

Periprosthetic joint infection (PJI) is a significant challenge to the orthopedic surgeon, patient, hospital, and insurance provider. Our study compares the financial information of self-originating and referral 2-stage revision hip and knee surgeries at our tertiary referral center for hip or knee PJI over the last 4 years. We performed an in-house retrospective financial review of all patients who underwent 2-stage revision hip or knee arthroplasty for infection between January 2008 and August 2013, comparing self-originating and referral cases. We found an increasing number of referrals over the study period. There was an increased cost of treating hips over knees. All scenarios generated a positive net income; however, referral hip PJIs offered lower reimbursement and net income per case (although not statistically significant), whereas knee PJIs offered higher reimbursement and net income per case (although not statistically significant). With referral centers treating increased numbers of infected joints performed elsewhere, we show continued financial incentive in accepting referrals, although with less financial gain than when treating one's own hip PJI and an increased financial gain when treating referral knee PJIs. Copyright © 2016 Elsevier Inc. All rights reserved.

Effects of plant density on the photosynthetic and chloroplast characteristics of maize under high-yielding conditions

NASA Astrophysics Data System (ADS)

Ren, Baizhao; Liu, Wei; Zhang, Jiwang; Dong, Shuting; Liu, Peng; Zhao, Bin

2017-04-01

Plant density has been recognized as a major factor determining the grain yield. The photosynthetic performance changes as the density increases. The main objective of this research was to evaluate responses of photosynthetic performance and chloroplast ultrastructure to planting densities in two summer maize ( Zea mays L.) hybrids Denghai661 (DH661) and Nongda108 (ND108). DH661 was planted at densities of 30,000, 45,000, 60,000, 75,000, 90,000, 105,000, 120,000, or 135,000 plants ha-1. ND108 was planted at densities of 30,000, 45,000, 60,000, 75,000, or 90,000 plants ha-1. Research variables included leaf area, grain yield, chlorophyll content, leaf gas exchange parameters, number of chloroplasts, and chloroplast ultrastructure. As plant density increased, chlorophyll a and b content significantly decreased; carotenoids initially decreased and then increased; the net photosynthetic rate during each growth period significantly decreased; the membrane structure of mesophyll cells was gradually damaged; the number of chloroplasts significantly decreased; the external form of chloroplasts shifted from long and oval to elliptical or circular; the number of grana significantly decreased, while the number of grana lamellae increased; grana gradually became hypogenetic and eventually dissolved; plot yield increased; and yield per plant significantly decreased. The yield per plant of DH661 at 135,000 plants ha-1 and that of ND108 at 90,000 plants ha-1 decreased by 65.8 and 42.5%, respectively, compared with those at 30,000 plants ha-1.

Knee Joint Kinetics in Relation to Commonly Prescribed Squat Loads and Depths

PubMed Central

Cotter, Joshua A.; Chaudhari, Ait M.; Jamison, Steve T.; Devor, Steven T.

2014-01-01

Controversy exists regarding the safety and performance benefits of performing the squat exercise to depths beyond 90° of knee flexion. Our aim was to compare the net peak external knee flexion moments (pEKFM) experienced over typical ranges of squat loads and depths. Sixteen recreationally trained males (n = 16; 22.7 ± 1.1 yrs; 85.4 ± 2.1 kg; 177.6 ± 0.96 cm; mean ± SEM) with no previous lower limb surgeries or other orthopedic issues and at least one year of consistent resistance training experience while utilizing the squat exercise performed single repetition squat trials in a random order at squat depths of above parallel, parallel, and below parallel. Less than one week before testing, one repetition maximum (1RM) values were found for each squat depth. Subsequent testing required subjects to perform squats at the three depths with three different loads: unloaded, 50% 1RM, and 85% 1RM (nine total trials). Force platform and kinematic data were collected to calculate pEKFM. To assess differences among loads and depths, a two-factor (load and depth) repeated-measures ANOVA with significance set at the P < 0.05 level was used. Squat 1RM significantly decreased 13.6% from the above parallel to parallel squat and another 3.6% from the parallel to the below parallel squat (P < 0.05). Net peak external knee flexion moments significantly increased as both squat depth and load were increased (P ≤ 0.02). Slopes of pEKFM were greater from unloaded to 50% 1RM than when progressing from 50% to 85% 1RM (P < 0.001). The results suggest that that typical decreases in squat loads used with increasing depths are not enough to offset increases in pEKFM. PMID:23085977

Model training across multiple breeding cycles significantly improves genomic prediction accuracy in rye (Secale cereale L.).

PubMed

Auinger, Hans-Jürgen; Schönleben, Manfred; Lehermeier, Christina; Schmidt, Malthe; Korzun, Viktor; Geiger, Hartwig H; Piepho, Hans-Peter; Gordillo, Andres; Wilde, Peer; Bauer, Eva; Schön, Chris-Carolin

2016-11-01

Genomic prediction accuracy can be significantly increased by model calibration across multiple breeding cycles as long as selection cycles are connected by common ancestors. In hybrid rye breeding, application of genome-based prediction is expected to increase selection gain because of long selection cycles in population improvement and development of hybrid components. Essentially two prediction scenarios arise: (1) prediction of the genetic value of lines from the same breeding cycle in which model training is performed and (2) prediction of lines from subsequent cycles. It is the latter from which a reduction in cycle length and consequently the strongest impact on selection gain is expected. We empirically investigated genome-based prediction of grain yield, plant height and thousand kernel weight within and across four selection cycles of a hybrid rye breeding program. Prediction performance was assessed using genomic and pedigree-based best linear unbiased prediction (GBLUP and PBLUP). A total of 1040 S 2 lines were genotyped with 16 k SNPs and each year testcrosses of 260 S 2 lines were phenotyped in seven or eight locations. The performance gap between GBLUP and PBLUP increased significantly for all traits when model calibration was performed on aggregated data from several cycles. Prediction accuracies obtained from cross-validation were in the order of 0.70 for all traits when data from all cycles (N CS  = 832) were used for model training and exceeded within-cycle accuracies in all cases. As long as selection cycles are connected by a sufficient number of common ancestors and prediction accuracy has not reached a plateau when increasing sample size, aggregating data from several preceding cycles is recommended for predicting genetic values in subsequent cycles despite decreasing relatedness over time.

Biomechanics of Hyperflexion and Kneeling before and after Total Knee Arthroplasty

PubMed Central

2014-01-01

The capacity to perform certain activities is frequently compromised after total knee arthroplasty (TKA) due to a functional decline resulting from decreased range of motion and a diminished ability to kneel. In this manuscript, the current biomechanical understanding of hyperflexion and kneeling before and after TKA will be discussed. Patellofemoral and tibiofemoral joint contact area, contact pressure, and kinematics were evaluated in cadaveric studies using a Tekscan pressure measuring system and Microscribe. Testing was performed on intact knees and following cruciate retaining and posterior stabilized TKA at knee flexion angles of 90°, 105°, 120°, and 135°. Three loading conditions were used to simulate squatting, double stance kneeling, and single stance kneeling. Following TKA with double stance kneeling, patellofemoral contact areas did not increase significantly at high knee flexion angle (135°). Kneeling resulted in tibial posterior translation and external rotation at all flexion angles. Moving from double to single stance kneeling tended to increase pressures in the cruciate retaining group, but decreased pressures in the posterior stabilized group. The cruciate retaining group had significantly larger contact areas than the posterior stabilized group, although no significant differences in pressures were observed comparing the two TKA designs (p < 0.05). If greater than 120° of postoperative knee range of motion can be achieved following TKA, then kneeling may be performed with less risk in the patellofemoral joint than was previously believed to be the case. However, kneeling may increase the likelihood of damage to cartilage and menisci in intact knees and after TKA increases in tibiofemoral contact area and pressures may lead to polyethyelene wear if performed on a chronic, repetitive basis. PMID:24900891

Biomechanics of hyperflexion and kneeling before and after total knee arthroplasty.

PubMed

Lee, Thay Q

2014-06-01

The capacity to perform certain activities is frequently compromised after total knee arthroplasty (TKA) due to a functional decline resulting from decreased range of motion and a diminished ability to kneel. In this manuscript, the current biomechanical understanding of hyperflexion and kneeling before and after TKA will be discussed. Patellofemoral and tibiofemoral joint contact area, contact pressure, and kinematics were evaluated in cadaveric studies using a Tekscan pressure measuring system and Microscribe. Testing was performed on intact knees and following cruciate retaining and posterior stabilized TKA at knee flexion angles of 90°, 105°, 120°, and 135°. Three loading conditions were used to simulate squatting, double stance kneeling, and single stance kneeling. Following TKA with double stance kneeling, patellofemoral contact areas did not increase significantly at high knee flexion angle (135°). Kneeling resulted in tibial posterior translation and external rotation at all flexion angles. Moving from double to single stance kneeling tended to increase pressures in the cruciate retaining group, but decreased pressures in the posterior stabilized group. The cruciate retaining group had significantly larger contact areas than the posterior stabilized group, although no significant differences in pressures were observed comparing the two TKA designs (p < 0.05). If greater than 120° of postoperative knee range of motion can be achieved following TKA, then kneeling may be performed with less risk in the patellofemoral joint than was previously believed to be the case. However, kneeling may increase the likelihood of damage to cartilage and menisci in intact knees and after TKA increases in tibiofemoral contact area and pressures may lead to polyethyelene wear if performed on a chronic, repetitive basis.

Effect of nifedipine on choroidal blood flow regulation during isometric exercise.

PubMed

Schmidl, Doreen; Prinz, Ana; Kolodjaschna, Julia; Polska, Elzbieta; Luksch, Alexandra; Fuchsjager-Mayrl, Gabriele; Garhofer, Gerhard; Schmetterer, Leopold

2012-01-25

To determine whether nifedipine, an L-type calcium channel blocker, alters choroidal blood flow (ChBF) regulation during isometric exercise in healthy subjects. The study was carried out in a randomized, placebo-controlled, double-masked, two-way crossover design. Fifteen healthy male subjects were randomly assigned to receive either placebo or nifedipine on two different study days. Subfoveal ChBF was measured with laser Doppler flowmetry while the study participants performed isometric exercise (squatting). This was performed before drug administration and during infusion of nifedipine and placebo, respectively. Mean arterial pressure (MAP) and intraocular pressure (IOP) were measured noninvasively, and ocular perfusion pressure (OPP) was calculated as ⅔ MAP-IOP. MAP and OPP increased significantly during all squatting periods (P < 0.01). The increase in ChBF was less pronounced than the increase in OPP during isometric exercise. Nifedipine did not alter the OPP increase in response to isometric exercise, but it significantly augmented the exercise-induced increase in ChBF (P < 0.001 vs. placebo). Although ChBF increased by a maximum of 14.2% ± 9.2% during the squatting period when placebo was administered, the maximum increase during administration of nifedipine was 23.2% ± 7.2%. In conclusion, the data of the present study suggest that nifedipine augments the ChBF response to an experimental increase in OPP. In addition, it confirms that the choroidal vasculature has a significant regulatory capacity over wide ranges of OPPs during isometric exercise. (ClinicalTrials.gov number, NCT00280462.).

Diversity begets diversity? The effects of board composition on the appointment and success of women CEOs.

PubMed

Cook, Alison; Glass, Christy

2015-09-01

Previous research on the effects of leadership diversity on firm outcomes has produced inconsistent and inconclusive findings. While some scholars argue that diversity increases organizational equity and enhances performance, others argue that diversity increases conflict, reduces cooperation and harms performance. This study tests the impact of a variety of compositional factors on firm outcomes. Specifically, we analyze whether and how board composition affects the advancement and mobility of women CEOs and firm performance. Our analysis relies on a unique data set of all Chief Executive Officers (CEOs) and Board of Directors (BODs) in Fortune 500 companies over a ten-year period. We find a marginally significant positive relationship between board diversity and the likelihood of a woman being appointed CEO. We further find that board diversity significantly and positively influences the post-promotion success of women CEOs. Our findings suggest that board composition is critical for the appointment and success of women CEOs, and increasing board diversity should be central to any organizational diversity efforts. Copyright © 2015 Elsevier Inc. All rights reserved.

Effects of Winglets on the Drag of a Low-Aspect-Ratio Configuration

NASA Technical Reports Server (NTRS)

Smith, Leigh Ann; Campbell, Richard L.

1996-01-01

A wind-tunnel investigation has been performed to determine the effect of winglets on the induced drag of a low-aspect-ratio wing configuration at Mach numbers between 0.30 and 0.85 and a nominal angle-of-attack range from -2 deg to 20 deg. Results of the tests at the cruise lift coefficient showed significant increases in lift-drag ratio for the winglet configuration relative to a wing-alone configuration designed for the same lift coefficient and Mach number. Further, even larger increases in lift-drag ratio were observed at lift coefficients above the design value at all Mach numbers tested. The addition of these winglets had a negligible effect on the static lateral-directional stability characteristics of the configuration. No tests were made to determine the effect of these winglets at supersonic Mach numbers, where increases in drag caused by winglets might be more significant. Computational analyses were also performed for the two configurations studied. Linear and small-disturbance formulations were used. The codes were found to give reasonable performance estimates sufficient for predicting changes of this magnitude.

A Biomechanical Comparison of the Long Snap in Football Between High School and University Football Players.

PubMed

Chizewski, Michael G; Alexander, Marion J L

2015-08-01

Limited previous research was located that examined the technique of the long snap in football. The purpose of the study was to compare the joint movements, joint velocities, and body positions used to perform fast and accurate long snaps in high school (HS) and university (UNI) athletes. Ten HS and 10 UNI subjects were recruited for filming, each performing 10 snaps at a target with the fastest and most accurate trial being selected for subject analysis. Eighty-three variables were measured using Dartfish Team Pro 4.5.2 video analysis software, with statistical analysis performed using Microsoft Excel and SPSS 16.0. Several significant comparisons to long snapping technique between groups were noted during analysis; however, the body position and movement variables at release showed the greatest number of significant differences. The UNI athletes demonstrated significantly higher release velocity and left elbow extension velocity, with significantly lower release height and release angle than the HS group. Total snap time (release time + total flight time) was determined to have the strongest correlation to release velocity for the HS group (r = -0.915) and UNI group (r = -0.918). The study suggests HS long snappers may benefit from less elbow flexion and more knee flexion in the backswing (set position) to increase release velocity. University long snappers may benefit from increased left elbow extension range of motion during force production and decreased shoulder flexion at critical instant to increase long snap release velocity.

Significantly Increasing the Ductility of High Performance Polymer Semiconductors through Polymer Blending.

PubMed

Scott, Joshua I; Xue, Xiao; Wang, Ming; Kline, R Joseph; Hoffman, Benjamin C; Dougherty, Daniel; Zhou, Chuanzhen; Bazan, Guillermo; O'Connor, Brendan T

2016-06-08

Polymer semiconductors based on donor-acceptor monomers have recently resulted in significant gains in field effect mobility in organic thin film transistors (OTFTs). These polymers incorporate fused aromatic rings and have been designed to have stiff planar backbones, resulting in strong intermolecular interactions, which subsequently result in stiff and brittle films. The complex synthesis typically required for these materials may also result in increased production costs. Thus, the development of methods to improve mechanical plasticity while lowering material consumption during fabrication will significantly improve opportunities for adoption in flexible and stretchable electronics. To achieve these goals, we consider blending a brittle donor-acceptor polymer, poly[4-(4,4-dihexadecyl-4H-cyclopenta[1,2-b:5,4-b']dithiophen-2-yl)-alt-[1,2,5]thiadiazolo[3,4-c]pyridine] (PCDTPT), with ductile poly(3-hexylthiophene). We found that the ductility of the blend films is significantly improved compared to that of neat PCDTPT films, and when the blend film is employed in an OTFT, the performance is largely maintained. The ability to maintain charge transport character is due to vertical segregation within the blend, while the improved ductility is due to intermixing of the polymers throughout the film thickness. Importantly, the application of large strains to the ductile films is shown to orient both polymers, which further increases charge carrier mobility. These results highlight a processing approach to achieve high performance polymer OTFTs that are electrically and mechanically optimized.

Host-derived probiotics Enterococcus casseliflavus improves resistance against Streptococcus iniae infection in rainbow trout (Oncorhynchus mykiss) via immunomodulation.

PubMed

Safari, Reza; Adel, Milad; Lazado, Carlo C; Caipang, Christopher Marlowe A; Dadar, Maryam

2016-05-01

The present study evaluated the benefits of dietary administration of host-derived candidate probiotics Enterococcus casseliflavus in juvenile rainbow trout Oncorhynchus mykiss. Experimental diets were prepared by incorporating the microorganisms in the basal feed at 3 inclusion levels (i.e. 10(7) CFU g(-1) of feed [T1], 10(8) CFU g(-1) of feed [T2], 10(9) CFU g(-1) of feed [T3]). The probiotic feeds were administered for 8 weeks, with a group fed with the basal diet serving as control. The effects on growth performance, gut health, innate immunity and disease resistance were evaluated. Results showed that growth performance parameters were significantly improved in T2 and T3 groups. Activities of digestive enzymes such as trypsin and lipase were significantly higher in these two groups as well. Gut micro-ecology was influenced by probiotic feeding as shown by the significant increase in intestinal lactic acid bacteria and total viable aerobic counts in T2 and T3. Humoral immunity was impacted by dietary probiotics as total serum protein and albumin were significantly elevated in T3. The levels of serum IgM significantly increased in all probiotic fed groups at week 8; with the T3 group registering the highest increment. Respiratory burst activity of blood leukocytes were significantly improved in T2 and T3. Hematological profiling further revealed that neutrophil counts significantly increased in all probiotic fed groups. Challenge test showed that probiotic feeding significantly improved host resistance to Streptococcus iniae infection, specifically in T2 and T3 where a considerable modulation of immune responses was observed. Taken together, this study demonstrated E. casseliflavus as a potential probiotics for rainbow trout with the capability of improving growth performance and enhancing disease resistance by immunomodulation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Increased iron level in phytase-supplemented diets reduces performance and nutrient utilisation in broiler chickens.

PubMed

Akter, Marjina; Iji, P A; Graham, H

2017-08-01

1. The effect of different levels of dietary iron on phytase activity and its subsequent effect on broiler performance were investigated in a 3 × 2 factorial arrangement. A total of 360 day-old Ross 308 male broiler chicks were distributed to 6 experimental diets, formulated with three levels of Fe (60, 80 and 100 mg/kg) and two levels of phytase (0 and 500 FTU/kg). 2. Phytase supplemented to mid-Fe diets increased feed consumption more than the non-supplemented diet at d 24. From hatch to d 35, Fe × phytase interaction significantly influenced the feed intake (FI), body weight gain (BWG) and feed conversion ratio (FCR). The high-Fe diet supplemented with phytase significantly reduced FI and BWG of broilers than those supplemented with low- or mid-Fe diets. The overall FCR was significantly better in birds fed on the mid-Fe diets with phytase supplementation. 3. A significant improvement in ileal digestibility of N, P, Mg and Fe was observed in birds feed diets containing 60 mg Fe/kg, with significant interaction between Fe and phytase. 4. Phytase improved the bone breaking strength when supplemented to low- or mid-Fe diets, compared to the non-supplemented diets. There was a significant Fe × phytase interaction effect. Tibia Fe content was higher in birds fed on phytase-free diets with high Fe but the reverse was the case when phytase was added and their interaction was significant. High dietary Fe significantly increased the accumulation of Fe in liver. 5. Phytase improved Ca-Mg-ATPase, Ca-ATPase and Mg-ATPase activities in jejunum when supplemented to the diet containing 80 mg Fe/kg. 6. This study indicates that high (100 mg/kg) dietary Fe inhibited phytase efficacy and subsequently reduced the overall performance and nutrient utilisation of broilers.

Installation and early performance of a field test section of asphalt rubber concrete.

DOT National Transportation Integrated Search

1991-01-01

Asphalt rubber, which is produced by reacting asphalt cement and crumb rubber, is claimed to increase fatigue life and reduce rutting of asphalt concrete; however, the service life must be increased significantly to offset the additional coast of add...

Excessive backfat of sows at 109 d of gestation induces lipotoxic placental environment and is associated with declining reproductive performance.

PubMed

Zhou, Yuanfei; Xu, Tao; Cai, Anle; Wu, Yinghui; Wei, Hongkui; Jiang, Siwen; Peng, Jian

2018-02-15

This study investigated the influence of sow backfat thickness at 109 d of gestation on sow and piglet performance. Data from 846 farrowing multiparous Yorkshire sows with parity from 3 to 5 were collected from a pig breeding farm. Sows were divided into six groups based on backfat thickness (≤16, 17-18, 19-20, 21-22, 23-24, and ≥25 mm) at 109 d of gestation. The evaluation of reproductive performance included the litter size, litter weight at birth and at weaning of 21 d, weight of placenta at parturition, placental efficiency, and sow daily feed intake of lactation. Parameters related to plasma lipids and the placental-lipid concentration were measured. Data were analyzed to determine the relationships among backfat thickness, placental lipids, and piglet performance. No differences were observed in the number of piglets born, born alive, after cross-foster, and at weaning among groups (P > 0.05). The litter weight at birth and weaning, piglet birth weight, weaning weight, placental efficiency, and the number and percentage of piglets born with weight of <800 g showed a significantly quadratic effect of the backfat thickness (P < 0.05). During lactation, sow daily feed intake linearly decreased with increased backfat thickness at 109 d of gestation (P < 0.05). Although triglycerides and low-density lipoprotein cholesterol (LDL-C) showed no significant difference, cholesterol and high-density lipoprotein cholesterol (HDL-C) and free fatty acid (FFA) concentrations significantly increased (P < 0.05) in both maternal and umbilical cord blood with increased backfat thickness of sow. Placental-lipid concentrations also significantly increased (P < 0.05) with increased backfat thickness. Moreover, backfat thickness and placental-lipid concentration were positively correlated with the number of piglets weighing <800 g (P < 0.01) but negatively correlated with birth weight, litter birth weight, and piglet weaned weight (P < 0.01). In conclusion, backfat thickness of sow at end of gestation correlates with birth and weaning weight of piglets. Placental ectopic lipid accumulation-induced lipotoxicity is likely responsible for such correlation.

Increased Muscle Sympathetic Nerve Activity and Impaired Executive Performance Capacity in Obstructive Sleep Apnea

PubMed Central

Goya, Thiago T.; Silva, Rosyvaldo F.; Guerra, Renan S.; Lima, Marta F.; Barbosa, Eline R.F.; Cunha, Paulo Jannuzzi; Lobo, Denise M.L.; Buchpiguel, Carlos A.; Busatto-Filho, Geraldo; Negrão, Carlos E.; Lorenzi-Filho, Geraldo; Ueno-Pardi, Linda M.

2016-01-01

Study Objectives: To investigate muscle sympathetic nerve activity (MSNA) response and executive performance during mental stress in obstructive sleep apnea (OSA). Methods: Individuals with no other comorbidities (age = 52 ± 1 y, body mass index = 29 ± 0.4, kg/m2) were divided into two groups: (1) control (n = 15) and (2) untreated OSA (n = 20) defined by polysomnography. Mini-Mental State of Examination (MMSE) and Inteligence quocient (IQ) were assessed. Heart rate (HR), blood pressure (BP), and MSNA (microneurography) were measured at baseline and during 3 min of the Stroop Color Word Test (SCWT). Sustained attention and inhibitory control were assessed by the number of correct answers and errors during SCWT. Results: Control and OSA groups (apnea-hypopnea index, AHI = 8 ± 1 and 47 ± 1 events/h, respectively) were similar in age, MMSE, and IQ. Baseline HR and BP were similar and increased similarly during SCWT in control and OSA groups. In contrast, baseline MSNA was higher in OSA compared to controls. Moreover, MSNA significantly increased in the third minute of SCWT in OSA, but remained unchanged in controls (P < 0.05). The number of correct answers was lower and the number of errors was significantly higher during the second and third minutes of SCWT in the OSA group (P < 0.05). There was a significant correlation (P < 0.01) between the number of errors in the third minute of SCWT with AHI (r = 0.59), arousal index (r = 0.55), and minimum O2 saturation (r = −0.57). Conclusions: As compared to controls, MSNA is increased in patients with OSA at rest, and further significant MSNA increments and worse executive performance are seen during mental stress. Clinical Trial Registration: URL: http://www.clinicaltrials.gov, registration number: NCT002289625. Citation: Goya TT, Silva RF, Guerra RS, Lima MF, Barbosa ER, Cunha PJ, Lobo DM, Buchpiguel CA, Busatto-Filho G, Negrão CE, Lorenzi-Filho G, Ueno-Pardi LM. Increased muscle sympathetic nerve activity and impaired executive performance capacity in obstructive sleep apnea. SLEEP 2016;39(1):25–33. PMID:26237773

Comparisons of low-intensity versus moderate-intensity combined aerobic and resistance training on body composition, muscle strength, and functional performance in older women.

PubMed

Shiotsu, Yoko; Yanagita, Masahiko

2018-06-01

This study aimed to examine the effects of exercise order of combined aerobic and low- or moderate-intensity resistance training into the same session on body composition, functional performance, and muscle strength in healthy older women. Furthermore, this study compared the effects of different (low- vs moderate-) intensity combined training. A total of 60 healthy older women (age 61-81 y) were randomly assigned to five groups that performed aerobic exercise before low-intensity resistance training (AR-L, n = 12) or after resistance training (RA-L, n = 12), performed aerobic exercise before moderate-intensity resistance training (AR-M, n = 12) or after resistance training (RA-M, n = 12), or nonintervention control conditions (CON, n = 12). Body composition, functional performance, and muscle strength were evaluated before and after the 10-week training. No effects of exercise order of combined aerobic and low- or moderate-intensity resistance training (AR-L vs RA-L, AR-M vs RA-M) were observed in body composition, functional performance, or muscle strength, whereas the effects of training intensity of combined training (AR-L vs AR-M, RA-L vs RA-M) were observed on functional performance. All combined trainings significantly increased muscle strength and gait ability (P < 0.01, respectively). Functional reach test significantly increased in the AR-M and RA-M groups (P < 0.01, respectively), and there were significant group differences between AR-L and AR-M (P = 0.002), RA-L and RA-M (P = 0.014). Preliminary findings suggest that combined aerobic and low- or moderate-intensity resistance training increases muscle strength and improves gait ability, regardless of the exercise order. Also, greater improvement in dynamic balance capacity, a risk factor associated with falling, is observed in moderate-intensity combined training.

The acute effects of manipulating volume and load of back squats on countermovement vertical jump performance.

PubMed

Moir, Gavin L; Mergy, David; Witmer, Ca; Davis, Shala E

2011-06-01

The acute effects of manipulating the volume and load of back squats on subsequent countermovement vertical jump performance were investigated in the present study. Eleven National Collegiate Athletic Association division II female volleyball players performed 10 countermovement vertical jumps (CMJs) on a force platform 2 minutes after the last squat repetition of a high-load (HL) or high-volume (HV) squat protocol. Two minutes of rest was provided between each CMJ. The HL protocol culminated in the subjects having to perform 3 repetitions with a load equivalent to 90% 1 repetition maximum (1RM) back squat, whereas 12 repetitions with a load equivalent to 37% 1RM were performed in the HV protocol. During an initial familiarization session, knee angles were recorded during a series of CMJs, and these angles were used to control the depth of descent during all subsequent back squats. Jump height (JH) and vertical stiffness (VStiff) were calculated during each of the 10 CMJ, and the change in these variables after the 2 squat protocols was assessed using an analysis of variance model with repeated measures on 2 factors (Protocol [2-levels]; Time [2-levels]). There was no significant difference in JH after the HL and HV protocols (p > 0.05). A significant Protocol × Time interaction for VStiff resulted from the increase after the HL protocol being greater than that after the HV protocol (p = 0.03). The knee angles before the HL and HV protocols were significantly greater than those measured during the initial familiarization session (p = 0.001). Although neither squat protocol provided any benefit in improving JH, the heavy squat protocol produced greater increases in VStiff during the CMJ. Because of the increased VStiff caused by the HL protocol, volleyball coaches may consider using such protocols with their players to improve performance in jumps performed from a run such as the spike and on-court agility.

Human torque velocity adaptations to sprint, endurance, or combined modes of training

NASA Technical Reports Server (NTRS)

Shealy, M. J.; Callister, R.; Dudley, G. A.; Fleck, S. J.

1992-01-01

We had groups of athletes perform sprint and endurance run training independently or concurrently for 8 weeks to examine the voluntary in vivo mechanical responses to each type of training. Pre- and posttraining angle-specific peak torque during knee extension and flexion were determined at 0, 0.84, 1.65, 2.51, 3.35, 4.19, and 5.03 radian.sec-1 and normalized for lean body mass. Knee extension torque in the sprint-trained group increased across all test velocities, the endurance-trained group increased at 2.51, 3.34, 4.19, and 5.03 radian.sec-1, and the group performing the combined training showed no change at any velocity. Knee flexion torque of the sprint and combined groups decreased at 0.84, 1.65, and 2.51 radian.sec-1. Knee flexion torque in the sprint-trained group also decreased at 0 radian.sec-1 and in the combined group at 3.34 radian.sec-1. Knee flexion torque in the endurance-trained group showed no change at any velocity of contraction. Mean knee flexion:extension ratios across the test velocities significantly decreased in the sprint-trained group. Knee extension endurance during 30 seconds of maximal contractions significantly increased in all groups. Only the sprint-trained group showed a significant increase in endurance of the knee flexors. These data suggest that changes in the voluntary in vivo mechanical characteristics of knee extensor and flexor skeletal muscles are specific to the type of run training performed.

Impact of a Home-Based Physical and Nutritional Intervention Program Conducted by Lay-Volunteers on Handgrip Strength in Prefrail and Frail Older Adults: A Randomized Control Trial.

PubMed

Haider, Sandra; Dorner, Thomas E; Luger, Eva; Kapan, Ali; Titze, Sylvia; Lackinger, Christian; Schindler, Karin E

2017-01-01

A randomized controlled trial was performed to compare the effects of a home-based physical and nutritional intervention program carried out by lay-volunteers to home visits with social support alone. Buddies visited 80 prefrail or frail older persons at home twice a week for 12 weeks. The physical training and nutrition group (PTN, n = 39) performed two sets of six strength exercises, discussed nutritional topics and received social support. The social support group (SoSu, n = 41) received home visits with social support only. In the PTN group, handgrip strength increased significantly by 2.4 kg (95% CI: 1.0-3.8). In the SoSu group we did not see a significant improvement. However, no significant between-group difference was found. Physical performance increased in both groups, although with a higher increase of 1.0 point (95% CI: 0.1-2.0) in the PTN group. In none of the groups muscle mass changed. Further results showed that frail individuals benefit more from the intervention than prefrail individuals (OR: 2.78; 95% CI: 1.01-7.66). Handgrip strength in the intervention group increased by a clinically relevant value and this effect is comparable to that obtained by health-care professionals. Therefore, home visits with a physical training and nutritional program could offer a new perspective in the care of community-dwelling prefrail and frail older persons.

Effect of Sea Buckthorn Leaves on Inosine Monophosphate and Adenylosuccinatelyase Gene Expression in Broilers during Heat Stress.

PubMed

Zhao, Wei; Chen, Xin; Yan, Changjiang; Liu, Hongnan; Zhang, Zhihong; Wang, Pengzu; Su, Jie; Li, Yao

2012-01-01

The trial was conducted to evaluate the effects of sea buckthorn leaves (SBL) on meat flavor in broilers during heat stress. A total 360 one-day-old Arbor Acre (AA) broilers (male) were randomly allotted to 4 treatments with 6 replicates pens pretreatment and 15 birds per pen. The control group was fed a basal diet, the experimental group I, II and III were fed the basal diet supplemented with 0.25%, 0.5%, 1% SBL, respectively. During the 4th week, broilers were exposed to heat stress conditions (36±2°C), after which, muscle and liver samples were collected. High performance liquid chromatography (HPLC) was performed to measure the content of inosine monophosphate (IMP); Real-Time PCR was performed to determine the expression of the ADSL gene. The results showed that the content of breast muscle IMP of group I, II and III was significantly increased 68%, 102% and 103% (p<0.01) compared with the control, respectively; the content of thigh muscle IMP of group II and III was significantly increased 56% and 58% (p<0.01), respectively. Additionally, ADSL mRNA expression in group I, II and III was increased significantly 80%, 65% and 49% (p<0.01) compared with the control, respectively. The content of IMP and expression of ADSL mRNA were increased by basal diet supplemented with SBL, therefore, the decrease of meat flavor caused by heat stress was relieved.

Daylighting in Schools: Improving Student Performance and Health at a Price Schools Can Afford.

ERIC Educational Resources Information Center

Plympton, Patricia; Conway, Susan; Epstein, Kyra

This document discusses evidence regarding daylighting and student performance and development, and presents four case studies of schools that have cost effectively implemented daylighting into their buildings. Case studies reveal that design and construction strategies that incorporate daylighting do not significantly increase costs over…

Reforming Education in England. OECD Economics Department Working Papers, No. 939

ERIC Educational Resources Information Center

Braconier, Henrik

2012-01-01

Despite significant increases in spending on child care and education during the last decade, PISA scores suggest that educational performance remains static, uneven and strongly related to parents' income and background. Better educational performance could improve labour market outcomes, raise growth, lower the consequences of a disadvantaged…

Entrepreneurship Projects and Pupils' Academic Performance: A Study of Norwegian Secondary Schools

ERIC Educational Resources Information Center

Johansen, Vegard; Schanke, Tuva

2014-01-01

Many European countries have launched policy strategies for entrepreneurship education in the past decade. The result is a significant increase of entrepreneurship education in schools and higher education institutions in Europe. Entrepreneurship education is supposed to promote entrepreneurial abilities and improve academic performance. This…

Increasing Effectiveness of Interagency Provincial Reconstruction Teams

DTIC Science & Technology

2007-03-29

harmony.30 During this phase the team’s ability to perform is developed and enhance by a sense of what the noted psychologist Albert Bandura of...perform…specific task[s].”31 Bandura goes on to state that these “efficacy beliefs contribute significantly to the level of motivation and performance

Meditation in Higher Education: Does It Enhance Cognition?

ERIC Educational Resources Information Center

Helber, Casey; Zook, Nancy A.; Immergut, Matthew

2012-01-01

We predicted that students in a sociology course that included contemplative practices (i.e., mindfulness meditation) would show an increase in performance on higher level cognitive abilities (executive functions) over the semester compared to a control group of students. Change in executive functions performance was not significantly different…

Mortality and cancer morbidity in workers exposed to low levels of vinyl chloride monomer at a polyvinyl chloride processing plant

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hagmar, L.; Akesson, B.; Nielsen, J.

1990-01-01

To study whether exposure to low levels of vinyl chloride monomer (VCM) causes increased risk for cancer morbidity and death from ischemic heart disease, a cohort study was performed among 2,031 male workers at a polyvinyl chloride (PVC) processing plant who had been employed for at least 3 months during the period 1945-1980. An almost significantly increased total mortality (SMR = 116, 95% CI 99-136) was found. Deaths caused by violence or intoxication were significantly increased (SMR = 153, 95% CI 109-213), but not deaths from ischemic heart disease (SMR = 100, 95% CI 73-135). A significant increase in totalmore » cancer morbidity was observed (SMR = 128, 95% CI 101-161). Respiratory cancers were significantly increased (SMR = 213, 95% CI 127-346). Furthermore, six brain tumors (vs. 2.6 expected) were observed. This increase, however, was not significant (SMR = 229, 95% CI 84-498). No liver hemangiosarcoma was observed. Applying a latency period of greater than or equal to 10 years from start of employment did not change the risk patterns. There were no significant exposure-response associations between exposure estimates for VCM, asbestos, and plasticizers and cancer morbidity.« less

Attendance and achievement in medicine: investigating the impact of attendance policies on academic performance of medical students.

PubMed

Subramaniam, Bs; Hande, S; Komattil, R

2013-04-01

The attendance mandate for the medical course in Melaka Manipal Medical College, Manipal, India was increased from 75% to 90% based on the assumption that the mandatory increase will improve the students' performance. To find out whether there is any correlation between class attendance and academic performance. This was an institution based retrospective analytical study. Students who have completed Phase I (first two and a half years) of the MBBS course were included in the study. Student marks and attendance, from the database were obtained from three random batches, each, from two clusters A and B respectively. Those who had a mandatory attendance requirement of 75% belonged to A (n = 243), and those who had a mandatory attendance percentage of 90% belonged to B (n = 360). Statistical analyses performed included, Pearson 2 tailed correlation to correlate class attendance with student performance; Cluster analysis to classify group average in a similarity matrix; t-test to determine significance of difference in percentage of students who attained 100% when the college changed mandatory attendance from 75% to 90%; Mann-Whitney test to find out if there was a better performance in university exam when attendance policy changed. There was a significant correlation between attendance and the students who passed in the University exam. The number of students in the pass category was maximum (>90%) compared to students in distinction and failed categories. Percentage of students with 100% attendance rose from 4% (n = 10) to 11% (n = 40) when the mandatory attendance was increased from 75% to 90%. Attendance policy correlated with better academic performance. Reducing absenteeism, probably contributed to the improved academic performance of the students. But the link between attendance and best and worst performances could not be predicted because of small numbers in every batch.

Blood pressure and neuropsychological test performance in healthy postmenopausal women.

PubMed

Alsumali, Adnan; Mekary, Rania A; Seeger, John; Regestein, Quentin

2016-06-01

To study the association between blood pressure and neuropsychological test performance in healthy postmenopausal women. Data from 88 healthy postmenopausal women aged 46-73 years, who were not experiencing hot flashes, and who had participated in a prior drug trial, were analyzed to find whether baseline blood pressure was associated with impaired performance on neuropsychological testing done at 3 follow-up visits separated by 4 weeks. Factor analysis was used to reduce the dimensions of neuropsychological test performance. Mixed linear modeling was used to evaluate the association between baseline blood pressure and repeatedly measured neuropsychological test performance at follow-up in a complete case analysis (n=53). In a sensitivity analysis (n=88), multiple-imputation using the Markov Chain Monte Carlo method was used to account for missing data (blood pressure results) for some visits. The variables recording neuropsychological test performance were reduced to two main factors (Factor 1=selective attention; Factor 2=complex processing). In the complete case analysis, the association between a 20-mmHg increase in diastolic blood pressure and Factor 1 remained statistically significant after adjusting for potential confounders, before adjusting for systolic blood pressure (slope=0.60; 95%CI=0.04,1.16), and after adjusting for systolic blood pressure (slope=0.76; 95%CI=0.06, 1.47). The positive slopes indicated an increase in the time spent performing a given task (i.e., a decrease in neuropsychological test performance). No other significant associations were found between systolic blood pressure and either factor. The results did not materially change after applying the multiple-imputation method. An increase in diastolic blood pressure was associated with a decrease in neuropsychological test performance among older healthy postmenopausal women experiencing hot flashes. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Effects of the Sports Level, Format of the Game and Task Condition on Heart Rate Responses, Technical and Tactical Performance of Youth Basketball Players

PubMed Central

Clemente, Filipe Manuel; González-Víllora, Sixto; Delextrat, Anne; Martins, Fernando Manuel Lourenço; Vicedo, Juan Carlos Pastor

2017-01-01

Abstract The aim of this study was to analyze the effect of different small-sided and conditioning games (SSCG) with different tactical contents on heart rate responses, technical performance and collective organization of youth basketball players of different performance levels. Twenty male basketball players from U14 (13.7 ± 0.8 years old; 4.2 ± 1.4 years of practice) and U16 (15.3 ± 1.1 years old; 6.4 ± 2.1 years of practice) participated in this research study. The two-way MANOVA revealed that the sports level (p = 0.009; ηp2 = 0.151), format (p = 0.001; ηp2 = 0.246) and task condition (p = 0.023; ηp2 = 0.104; small effect size) had significant main effects on heart rate responses. It was also found that the format (p = 0.001; ηp2 = 0.182) had significant main effects on technical performance. A smaller format significantly increased the heart rate, volume of play, efficiency index and collective density during attacking plays. The SSCG with attacking content statistically increased the heart rate, efficiency index and performance score. Therefore, this study revealed that different SSCGs with tactical content influenced the physiological responses of youth players. PMID:28828085

Chromium picolinate effects on body composition and muscular performance in wrestlers.

PubMed

Walker, L S; Bemben, M G; Bemben, D A; Knehans, A W

1998-12-01

The purpose of this study was to assess the effects of 14 wk of chromium picolinate supplementation during the final 16 wk of a preseason resistance and conditioning program on body composition and neuromuscular performance in NCAA Division I wrestlers. During this phase of training, wrestlers are primarily interested in trying to improve physical performance and wrestling technique and are not engaged in severe, acute weight loss practices commonly employed before competition. This double-blinded, randomized placebo-controlled study involved 20 wrestlers from the University of Oklahoma assigned to either a treatment group (Cr+3; N = 7; 20.4 yr +/- 0.1) receiving 200 micrograms chromium picolinate daily, a placebo group (P; N = 7; 19.9 yr +/- 0.2), or a control group (C; N = 6; 20.2 yr +/- 0.1) using a stratified random sampling technique based on weight classification. Body composition, neuromuscular performance, metabolic performance, and serum insulin and glucose were measured before and immediately following the supplementation and training period. Repeated measures ANOVA indicated no significant changes in body composition for any of the groups. Aerobic power increased significantly (P < 0.002) in all groups, independent of supplementation. There were significant trial and group x trial interactions for upper body endurance (P = 0.038) and relative bench press power (P = 0.050). Post-hoc analyses revealed that the C group increased upper body endurance (P = 0.006), but none of the pre- to post-test changes in bench press power were significant. These results suggest that chromium picolinate supplementation coupled with a typical preseason training program does not enhance body composition or performance variables beyond improvements seen with training alone.

A Comparison of Mixed-Method Cooling Interventions on Preloaded Running Performance in the Heat.

PubMed

Stevens, Christopher J; Bennett, Kyle J M; Sculley, Dean V; Callister, Robin; Taylor, Lee; Dascombe, Ben J

2017-03-01

Stevens, CJ, Bennett, KJM, Sculley, DV, Callister, R, Taylor, L, and Dascombe, BJ. A comparison of mixed-method cooling interventions on preloaded running performance in the heat. J Strength Cond Res 31(3): 620-629, 2017-The purpose of this investigation was to assess the effect of combining practical methods to cool the body on endurance running performance and physiology in the heat. Eleven trained male runners completed 4 randomized, preloaded running time trials (20 minutes at 70% V[Combining Dot Above]O2max and a 3 km time trial) on a nonmotorized treadmill in the heat (33° C). Trials consisted of precooling by combined cold-water immersion and ice slurry ingestion (PRE), midcooling by combined facial water spray and menthol mouth rinse (MID), a combination of all methods (ALL), and control (CON). Performance time was significantly faster in MID (13.7 ± 1.2 minutes; p < 0.01) and ALL (13.7 ± 1.4 minutes; p = 0.04) but not PRE (13.9 ± 1.4 minutes; p = 0.24) when compared with CON (14.2 ± 1.2 minutes). Precooling significantly reduced rectal temperature (initially by 0.5 ± 0.2° C), mean skin temperature, heart rate and sweat rate, and increased iEMG activity, whereas midcooling significantly increased expired air volume and respiratory exchange ratio compared with control. Significant decreases in forehead temperature, thermal sensation, and postexercise blood prolactin concentration were observed in all conditions compared with control. Performance was improved with midcooling, whereas precooling had little or no influence. Midcooling may have improved performance through an attenuated inhibitory psychophysiological and endocrine response to the heat.

Increased Muscle Sympathetic Nerve Activity and Impaired Executive Performance Capacity in Obstructive Sleep Apnea.

PubMed

Goya, Thiago T; Silva, Rosyvaldo F; Guerra, Renan S; Lima, Marta F; Barbosa, Eline R F; Cunha, Paulo Jannuzzi; Lobo, Denise M L; Buchpiguel, Carlos A; Busatto-Filho, Geraldo; Negrão, Carlos E; Lorenzi-Filho, Geraldo; Ueno-Pardi, Linda M

2016-01-01

To investigate muscle sympathetic nerve activity (MSNA) response and executive performance during mental stress in obstructive sleep apnea (OSA). Individuals with no other comorbidities (age = 52 ± 1 y, body mass index = 29 ± 0.4, kg/m2) were divided into two groups: (1) control (n = 15) and (2) untreated OSA (n = 20) defined by polysomnography. Mini-Mental State of Examination (MMSE) and Inteligence quocient (IQ) were assessed. Heart rate (HR), blood pressure (BP), and MSNA (microneurography) were measured at baseline and during 3 min of the Stroop Color Word Test (SCWT). Sustained attention and inhibitory control were assessed by the number of correct answers and errors during SCWT. Control and OSA groups (apnea-hypopnea index, AHI = 8 ± 1 and 47 ± 1 events/h, respectively) were similar in age, MMSE, and IQ. Baseline HR and BP were similar and increased similarly during SCWT in control and OSA groups. In contrast, baseline MSNA was higher in OSA compared to controls. Moreover, MSNA significantly increased in the third minute of SCWT in OSA, but remained unchanged in controls (P < 0.05). The number of correct answers was lower and the number of errors was significantly higher during the second and third minutes of SCWT in the OSA group (P < 0.05). There was a significant correlation (P < 0.01) between the number of errors in the third minute of SCWT with AHI (r = 0.59), arousal index (r = 0.55), and minimum O2 saturation (r = -0.57). As compared to controls, MSNA is increased in patients with OSA at rest, and further significant MSNA increments and worse executive performance are seen during mental stress. URL: http://www.clinicaltrials.gov, registration number: NCT002289625. © 2016 Associated Professional Sleep Societies, LLC.

Effects of a Multi-Ingredient Energy Supplement on Cognitive Performance and Cerebral-Cortical Activation.

PubMed

Daou, Marcos; Sassi, Julia Montagner; Miller, Matthew W; Gonzalez, Adam M

2018-03-13

This study assessed whether a multi-ingredient energy supplement (MIES) could enhance cerebral-cortical activation and cognitive performance during an attention-switching task. Cerebral-cortical activation was recorded in 24 young adults (12 males, 12 females; 22.8 ± 3.8 yrs) via electroencephalography (EEG) both at rest and during the attention-switching task before (pretest) and 30 min after (posttest) consumption of a single serving of a MIES (MIES-1), two servings of a MIES (MIES-2), or a placebo (PL) in a double-blinded, randomized crossover experimental design. EEG upper-alpha power was assessed at rest and during the task, wherein d' (Z[hit rate]-Z[false alarm rate]) and median reaction time (RT) for correct responses to targets on attention-hold and attention-switch trials were analyzed. For both d' and RT, the Session (MIES-1, MIES-2, PL) × Time (pretest, posttest) interaction approached statistical significance (p = .07, η 2 p = 0.106). Exploring these interactions with linear contrasts, a significant linear effect of supplement dose on the linear effect of time was observed (ps ≤.034), suggesting the pretest-to-posttest improvement in sensitivity to task target stimuli (d') and RT increased as a function of supplement dose. With respect to upper-alpha power, the Session × Time interaction was significant (p < .001, η 2 p = 0.422). Exploring this interaction with linear contrasts, a significant linear effect of supplement dose on the linear effect of time was observed (p < .001), suggesting pretest-to-posttest increases in cerebral-cortical activation were a function of supplement dose. In conclusion, our findings suggest that MIES can increase cerebral-cortical activation and RT during task performance while increasing sensitivity to target stimuli in a dose-dependent manner.

The effect of dietary cricket meal (Gryllus bimaculatus) on growth performance, antioxidant enzyme activities, and haematological response of African catfish (Clarias gariepinus).

PubMed

Taufek, Norhidayah Mohd; Aspani, Firdaus; Muin, Hasniyati; Raji, Ameenat Abiodun; Razak, Shaharudin Abdul; Alias, Zazali

2016-08-01

This study was conducted to investigate the growth performance, biomarkers of oxidative stress, catalase (CAT), superoxide dismutase (SOD), and glutathione S-transferase (GST) as well as the haematological response of African catfish after being fed with fish feed containing different levels of cricket meal. The juvenile fish were assigned to three different treatments with isonitrogenous (35 %) and isoenergetic (19 kJ g(-1)) diets containing 100 % cricket meal (100 % CM), 75 % cricket meal (75 % CM), and 100 % fishmeal (100 % FM) as control groups for 7 weeks. The results indicated that a diet containing 100 % CM and 75 % CM improved growth performance in terms of body weight gain and specific growth rate, when compared to 100 % FM. The feed conversion ratio (FCR) and protein efficiency ratio (PER) did not differ significantly between all diets, but reduced FCR and increased PER were observed with a higher inclusion of cricket meal. A haematological examination of fish demonstrated no significant difference of red blood cells in all diets and white blood cells showed a significantly higher value in fishmeal-fed fish. On the other hand, haemoglobin and haematocrit significantly increased with increasing amounts of cricket meal in the diet. Antioxidant activity of CAT was higher in the 100 % CM group compared to fish fed other diets, whereas GST and SOD showed increasing trends with a higher incorporation of cricket, although insignificant differences were observed between all diets. These results suggest that cricket meal could be an alternative to fishmeal as a protein source in the African catfish diet.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Patel, TN; Park, AHA; Bantat, S

The limited permeability of the E. coli outer membrane can significantly hinder whole-cell biocatalyst performance. In this study, the SARS coronavirus small envelope protein (SCVE) was expressed in E. coli cells previously engineered for periplasmic expression of carbonic anhydrase (CA) activity. This maneuver increased small molecule uptake by the cells, resulting in increased apparent CA activity of the biocatalysts. The enhancements in activity were quantified using methods developed for traditional heterogeneous catalysis. The expression of the SCVE protein was found to significantly reduce the Thiele moduli (phi), as well as increase the effectiveness factors (eta), effective diffusivities (D-e), and permeabilitiesmore » (P) of the biocatalysts. These catalytic improvements translated into superior performance of the biocatalysts for the precipitation of calcium carbonate from solution which is an attractive strategy for long-term sequestration of captured carbon dioxide. Overall, these results demonstrate that synthetic biology approaches can be used to enhance heterogeneous catalysts incorporated into microbial whole-cell scaffolds.« less

The American Quarter Horse: Population Structure and Relationship to the Thoroughbred

PubMed Central

2014-01-01

A breed known for its versatility, the American Quarter Horse (QH), is increasingly bred for performance in specific disciplines. The impact of selective breeding on the diversity and structure of the QH breed was evaluated using pedigree analysis and genome-wide SNP data from horses representing 6 performance groups (halter, western pleasure, reining, working cow, cutting, and racing). Genotype data (36 037 single nucleotide polymorphisms [SNPs]) from 36 Thoroughbreds were also evaluated with those from the 132 performing QHs to evaluate the Thoroughbred’s influence on QH diversity. Results showed significant population structure among all QH performance groups excepting the comparison between the cutting and working cow horses; divergence was greatest between the cutting and racing QHs, the latter of which had a large contribution of Thoroughbred ancestry. Significant coancestry and the potential for inbreeding exist within performance groups, especially when considering the elite performers. Relatedness within performance groups is increasing with popular sires contributing disproportionate levels of variation to each discipline. Expected heterozygosity, inbreeding, F ST, cluster, and haplotype analyses suggest these QHs can be broadly classified into 3 categories: stock, racing, and pleasure/halter. Although the QH breed as a whole contains substantial genetic diversity, current breeding practices have resulted in this variation being sequestered into subpopulations. PMID:24293614

Carryover effect of hip and knee exercises program on functional performance in individuals with patellofemoral pain syndrome

PubMed Central

Ahmed Hamada, Hamada; Hussein Draz, Amira; Koura, Ghada Mohamed; Saab, Ibtissam M.

2017-01-01

[Purpose] This study was carried out to investigate the carryover effect of hip and knee exercises program on functional performance (single legged hop test as functional performance test and Kujala score for functional activities). [Subjects and Methods] Thirty patients with patellofemoral pain syndrome were randomly assigned into two equal groups. Group (A) consisted of 15 patients undergoing hip strengthening exercises for four weeks then measuring all variables followed by additional four weeks of knee exercises program then measuring all variables again. Group (B): consisted of 15 patients undergoing knee exercises program for four weeks then measuring all variables followed by additional four weeks of hip strengthening exercises then measuring all variables. Functional abilities and knee muscles performance were assessed using Kujala questionnaire and single legged hop test respectively pre and after the completion of the first 4 weeks then after 8 weeks for both groups. [Results] Significantly increase in Kujala questionnaire in group A compared with group B was observed. While, there were significant increase in single legged hop performance test in group B compared with group A. [Conclusion] Starting with hip exercises improve the performance of subjects more than functional activities while starting with knee exercises improve the functional activities of subjects more than performance. PMID:28878459

Carryover effect of hip and knee exercises program on functional performance in individuals with patellofemoral pain syndrome.

PubMed

Ahmed Hamada, Hamada; Hussein Draz, Amira; Koura, Ghada Mohamed; Saab, Ibtissam M

2017-08-01

[Purpose] This study was carried out to investigate the carryover effect of hip and knee exercises program on functional performance (single legged hop test as functional performance test and Kujala score for functional activities). [Subjects and Methods] Thirty patients with patellofemoral pain syndrome were randomly assigned into two equal groups. Group (A) consisted of 15 patients undergoing hip strengthening exercises for four weeks then measuring all variables followed by additional four weeks of knee exercises program then measuring all variables again. Group (B): consisted of 15 patients undergoing knee exercises program for four weeks then measuring all variables followed by additional four weeks of hip strengthening exercises then measuring all variables. Functional abilities and knee muscles performance were assessed using Kujala questionnaire and single legged hop test respectively pre and after the completion of the first 4 weeks then after 8 weeks for both groups. [Results] Significantly increase in Kujala questionnaire in group A compared with group B was observed. While, there were significant increase in single legged hop performance test in group B compared with group A. [Conclusion] Starting with hip exercises improve the performance of subjects more than functional activities while starting with knee exercises improve the functional activities of subjects more than performance.

[Vitamin and mineral supplements in the diet of military personnel: effect on the balance of iron, copper and manganese, immune reactivity and physical work-capacity].

PubMed

Zaĭtseva, I P; Nosolodin, V V; Zaĭtsev, O N; Gladkikh, I P; Koznienko, I V; Beliakov, R A; Arshinov, N P

2012-03-01

Conducted with the participation of 50 students of military educational study the effect of various vitamin and mineral complexes for the provision by the body naturally iron, copper and manganese on the immune and physical status. Found that diets enriched BMV was accompanied by a significant delay in the micro-elements, mainly iron, which indicates a deficiency of these bioelements in chickens Santo during the summer. Under the influence of vitamin-mineral complexes significantly increased rates of natural and specific immunity. As the delay increases significantly increased iron medical indicators of immunological reaction efficiency and physical performance.

Home field advantage: new stadium construction and team performance in professional sports.

PubMed

Watson, Jack C; Krantz, Andrew J

2003-12-01

To identify the relations between new stadiums and home team performance and attendance for professional baseball (MLB) (n=14), basketball (NBA) (n=13), and football (NFL) (n=25) teams in the USA since 1950 dependent t tests assessed significance of increases in attendance in both MLB and the NBA and a significantly improved home winning percentage in MLB following the building of new stadiums. Implications include a better understanding of the rationales used by owners, fans, and players for building new stadiums.

beta-Mannanase ameliorates viscosity-associated depression of growth in broiler chickens fed guar germ and hull fractions.

PubMed

Lee, J T; Bailey, C A; Cartwright, A L

2003-12-01

High concentrations of guar meal in broiler chicken diets reduce body weight and feed efficiency. The increased intestinal viscosity that is responsible for reduced measures of performance results from residual guar gum present in guar meal. Two experiments were designed to study the effects of 2 guar meal fractions at 3 different concentrations, germ (0, 5.0, and 7.5%) and hull (0, 2.5, and 5.0%), and the effectiveness of a beta-mannanase at three levels (0, 1x, and 4x; 1x = 1.09 x 10(5) units/ kg) on broiler growth and feed conversion. Growth and performance were measured as a function of intestinal viscosity. Addition of the germ fraction to rations did not reduce body weight, although feed conversion ratio was increased at 7.5% of the diet. Intestinal viscosity also increased significantly at this level. Enzyme addition significantly reduced intestinal viscosity. Due to an interaction that was present between hull and enzyme concentration, each treatment was compared separately. Inclusion of the hull fraction significantly reduced body weight at both levels of inclusion and increased feed conversion ratio at 5% inclusion. Addition of the enzyme significantly increased body weight and reduced feed conversion ratio in diets containing guar hull fractions. Supplementation of beta-mannanase to feeds containing either fraction of guar meal reduced intestinal viscosity and alleviated the deleterious effects associated with guar meal feeding.

Breakfast skipping in prepubertal obese children: hormonal, metabolic and cognitive consequences.

PubMed

Maffeis, C; Fornari, E; Surano, M G; Comencini, E; Corradi, M; Tommasi, M; Fasan, I; Cortese, S

2012-03-01

Skipping breakfast influences cognitive performance. The aim of our study was to investigate the relationship between the variation of hormonal and metabolic postprandial parameters induced by breakfast consumption or fasting and cognitive performance in obese children. Cross-sectional study for repeated measures. Memory and attention assessment tests, hormones and nutrient oxidation were measured before and after consuming breakfast vs fasting in 10 prepubertal obese children. Fasting induced a significant (P<0.05) increase of the Overall Index of the Continuous Performance Test II (a global index of inattention) and the Test of Memory and Learning Word Selective Reminding (a test of verbal memory), whereas no changes were found after breakfast. Fasting was associated with a reduction of insulin and an increase in glucagon, with no changes in glucose. The increase in inattention was associated with a reduction of carbohydrate oxidation (ρ=-0.66, P<0.05). We found no difference in the area under the curve of peptide YY and glucagon-like peptide-1 after breakfast or fasting, whereas Ghrelin was significantly lower. No association between postprandial hormone variation and cognitive performance was found. Attention and visual memory performance in the morning were reduced when the children skipped breakfast. No association was found with hormones or metabolic changes, but we did find an association with a reduction of carbohydrate oxidation. Nevertheless, these preliminary findings need confirmation in larger sample size.

Investigation on heat transfer characteristics and flow performance of Methane at supercritical pressures

NASA Astrophysics Data System (ADS)

Xian, Hong Wei; Oumer, A. N.; Basrawi, F.; Mamat, Rizalman; Abdullah, A. A.

2018-04-01

The aim of this study is to investigate the heat transfer and flow characteristic of cryogenic methane in regenerative cooling system at supercritical pressures. The thermo-physical properties of supercritical methane were obtained from the National institute of Standards and Technology (NIST) webbook. The numerical model was developed based on the assumptions of steady, turbulent and Newtonian flow. For mesh independence test and model validation, the simulation results were compared with published experimental results. The effect of four different performance parameter ranges namely inlet pressure (5 to 8 MPa), inlet temperature (120 to 150 K), heat flux (2 to 5 MW/m2) and mass flux (7000 to 15000 kg/m2s) on heat transfer and flow performances were investigated. It was found that the simulation results showed good agreement with experimental data with maximum deviation of 10 % which indicates the validity of the developed model. At low inlet temperature, the change of specific heat capacity at near-wall region along the tube length was not significant while the pressure drop registered was high. However, significant variation was observed for the case of higher inlet temperature. It was also observed that the heat transfer performance and pressure drop penalty increased when the mass flux was increased. Regarding the effect of inlet pressure, the heat transfer performance and pressure drop results decreased when the inlet pressure is increased.

Effects of valerian on subjective sedation, field sobriety testing and driving simulator performance.

PubMed

Thomas, Kelan; Canedo, Joanne; Perry, Paul J; Doroudgar, Shadi; Lopes, Ingrid; Chuang, Hannah Mae; Bohnert, Kimberly

2016-07-01

The availability of herbal medicines over-the-counter (OTC) has increased the use of natural products for self-treatment. Valerian has been used to effectively treat generalized anxiety disorder and insomnia. Studies suggest that valerenic acid may increase gamma-aminobutyric acid (GABA) modulation in the brain. Benzodiazepines have a similar mechanism of action and have been linked to an increased risk of hospitalizations due to traffic accidents. Despite the risk of somnolence, the safety of driving while under the influence of valerian remains unknown. The purpose of the study was to determine the effects of a one-time valerian 1600mg dose on subjective sedation effects, standardized field sobriety testing (SFST) and driving simulator performance parameters. The study design was a randomized, placebo-controlled, double-blind, cross-over trial. For each session, participants received either a dose of valerian or placebo. The outcome measures included a simple visual reaction test (SVRT), subjective sleepiness scales, SFST performance scores, and driving simulator performance parameters. There were no significant differences in the SVRT or sleepiness scales between placebo and valerian exposures, but the study may have been underpowered. SFST total and individual test failure rates were not significantly different between the two exposures. The driving simulator performance parameters were equivalent between the two exposure conditions. A one-time valerian 1600mg dose, often used to treat insomnia, does not appear to impair driving simulator performance after acute ingestion. Copyright © 2016 Elsevier Ltd. All rights reserved.

Decreased coronary vasodilatory capacity in hypertrophic cardiomyopathy determined by split-dose thallium-dipyridamole myocardial scintigraphy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koga, Y.; Yamaguchi, R.; Ogata, M.

1990-05-01

Split-dose thallium-dipyridamole myocardial scintigraphy was performed in patients with nonobstructive hypertrophic cardiomyopathy (HC) who had angiographically normal coronary arteries. The dipyridamole-induced increases in thallium-201 uptake, calculated to evaluate coronary vasodilatory capacity, were significantly lower in 30 patients with HC than in 13 control subjects (177 +/- 58 vs 281 +/- 46%) and the reductions were observed in both the septal and lateral segments. The reductions of the septal segment in HC patients were significantly greater than those in 10 hypertensive patients with comparable degrees of septal hypertrophy. Of patients with HC, 16 had increases in thallium uptake well below themore » normal range. Compared with those having normal increases, these patients had significantly lower exercise duration (11 vs 15 minutes), with 33% having ST depression develop at a workload less than or equal to 80 watts. These data indicate that approximately one-half of patients with HC have impaired coronary vasodilatory capacity that could be an important pathophysiologic abnormality of HC resulting in the development of myocardial ischemia and the impairment of cardiac performance during exercise.« less

Cytogenetic analysis of children under long-term antibacterial therapy with nitroheterocyclic compound furagin.

PubMed

Slapsyte, G; Jankauskiene, A; Mierauskiene, J; Lazutka, J R

2001-04-05

Cytogenetic analysis of chromosome aberrations (CAs) and sister chromatid exchanges (SCEs) was performed in 109 blood samples from 95 pediatric patients with urinary tract infections (UTIs). Children were exposed to diagnostic levels of X-rays during voiding cystourethrography and subsequently treated for one to 12 months with low doses of furagin - N-(5-nitro-2-furyl)-allylidene-1-aminohydantoin. Furagin is 2-substituted 5-nitrofuran, chemically and structurally similar to well-known antibacterial compound nitrofurantoin. Increased frequencies of CAs were found in children undergoing voiding cystourethrography as compared with the unexposed, acentric fragments being the most frequent alteration (2.03 versus 0.88 per 100 cells, P=0.006). However, a significant decrease in the frequency of acentric fragments was determined with the time elapsed since X-ray examination was performed. A time-independent increase in SCE frequency was found in lymphocytes of children treated with furagin. Total CA frequency did not differ significantly between groups of children with various duration of furagin treatment. However, frequency of chromatid exchanges (triradials and quadriradials) increased significantly with duration of treatment.

Effects of Alcohol on Performance on a Distraction Task During Simulated Driving

PubMed Central

Allen, Allyssa J.; Meda, Shashwath A.; Skudlarski, Pawel; Calhoun, Vince; Astur, Robert; Ruopp, Kathryn C.; Pearlson, Godfrey D.

2009-01-01

Background Prior studies report that accidents involving intoxicated drivers are more likely to occur during performance of secondary tasks. We studied this phenomenon, using a dual-task paradigm, involving performance of a visual oddball (VO) task while driving in an alcohol challenge paradigm. Previous functional MRI (fMRI) studies of the VO task have shown activation in the anterior cingulate, hippocampus, and prefrontal cortex. Thus, we predicted dose-dependent decreases in activation of these areas during VO performance. Methods Forty healthy social drinkers were administered 3 different doses of alcohol, individually tailored to their gender and weight. Participants performed a VO task while operating a virtual reality driving simulator in a 3T fMRI scanner. Results Analysis showed a dose-dependent linear decrease in Blood Oxygen Level Dependent activation during task performance, primarily in hippocampus, anterior cingulate, and dorsolateral prefrontal areas, with the least activation occurring during the high dose. Behavioral analysis showed a dose-dependent linear increase in reaction time, with no effects associated with either correct hits or false alarms. In all dose conditions, driving speed decreased significantly after a VO stimulus. However, at the high dose this decrease was significantly less. Passenger-side line crossings significantly increased at the high dose. Conclusions These results suggest that driving impairment during secondary task performance may be associated with alcohol-related effects on the above brain regions, which are involved with attentional processing/decision-making. Drivers with high blood alcohol concentrations may be less able to orient or detect novel or sudden stimuli during driving. PMID:19183133

Basic life support skills of high school students before and after cardiopulmonary resuscitation training: a longitudinal investigation.

PubMed

Meissner, Theresa M; Kloppe, Cordula; Hanefeld, Christoph

2012-04-14

Immediate bystander cardiopulmonary resuscitation (CPR) significantly improves survival after a sudden cardiopulmonary collapse. This study assessed the basic life support (BLS) knowledge and performance of high school students before and after CPR training. This study included 132 teenagers (mean age 14.6 ± 1.4 years). Students completed a two-hour training course that provided theoretical background on sudden cardiac death (SCD) and a hands-on CPR tutorial. They were asked to perform BLS on a manikin to simulate an SCD scenario before the training. Afterwards, participants encountered the same scenario and completed a questionnaire for self-assessment of their pre- and post-training confidence. Four months later, we assessed the knowledge retention rate of the participants with a BLS performance score. Before the training, 29.5% of students performed chest compressions as compared to 99.2% post-training (P < 0.05). At the four-month follow-up, 99% of students still performed correct chest compressions. The overall improvement, assessed by the BLS performance score, was also statistically significant (median of 4 and 10 pre- and post-training, respectively, P < 0.05). After the training, 99.2% stated that they felt confident about performing CPR, as compared to 26.9% (P < 0.05) before the training. BLS training in high school seems highly effective considering the minimal amount of previous knowledge the students possess. We observed significant improvement and a good retention rate four months after training. Increasing the number of trained students may minimize the reluctance to conduct bystander CPR and increase the number of positive outcomes after sudden cardiopulmonary collapse.

MiR-137-derived polygenic risk: effects on cognitive performance in patients with schizophrenia and controls.

PubMed

Cosgrove, D; Harold, D; Mothersill, O; Anney, R; Hill, M J; Bray, N J; Blokland, G; Petryshen, T; Richards, A; Mantripragada, K; Owen, M; O'Donovan, M C; Gill, M; Corvin, A; Morris, D W; Donohoe, G

2017-01-24

Variants at microRNA-137 (MIR137), one of the most strongly associated schizophrenia risk loci identified to date, have been associated with poorer cognitive performance. As microRNA-137 is known to regulate the expression of ~1900 other genes, including several that are independently associated with schizophrenia, we tested whether this gene set was also associated with variation in cognitive performance. Our analysis was based on an empirically derived list of genes whose expression was altered by manipulation of MIR137 expression. This list was cross-referenced with genome-wide schizophrenia association data to construct individual polygenic scores. We then tested, in a sample of 808 patients and 192 controls, whether these risk scores were associated with altered performance on cognitive functions known to be affected in schizophrenia. A subgroup of healthy participants also underwent functional imaging during memory (n=108) and face processing tasks (n=83). Increased polygenic risk within the empirically derived miR-137 regulated gene score was associated with significantly lower performance on intelligence quotient, working memory and episodic memory. These effects were observed most clearly at a polygenic threshold of P=0.05, although significant results were observed at all three thresholds analyzed. This association was found independently for the gene set as a whole, excluding the schizophrenia-associated MIR137 SNP itself. Analysis of the spatial working memory fMRI task further suggested that increased risk score (thresholded at P=10 -5 ) was significantly associated with increased activation of the right inferior occipital gyrus. In conclusion, these data are consistent with emerging evidence that MIR137 associated risk for schizophrenia may relate to its broader downstream genetic effects.

Personality correlates (BAS-BIS), self-perception of social ranking, and cortical (alpha frequency band) modulation in peer-group comparison.

PubMed

Balconi, Michela; Pagani, Silvia

2014-06-22

The perception and interpretation of social hierarchies are a key part of our social life. In the present research we considered the activation of cortical areas, mainly the prefrontal cortex, related to social ranking perception in conjunction with some personality components (BAS - Behavioral Activation System - and BIS - Behavioral Inhibition System). In two experiments we manipulated the perceived superior/inferior status during a competitive cognitive task. Indeed, we created an explicit and strongly reinforced social hierarchy based on incidental rating in an attentional task. Specifically, a peer group comparison was undertaken and improved (Experiment 1) or decreased (Experiment 2) performance was artificially manipulated by the experimenter. For each experiment two groups were compared, based on a BAS and BIS dichotomy. Alpha band modulation in prefrontal cortex, behavioral measures (performance: error rate, ER; response times, RTs), and self-perceived ranking were considered. Repeated measures ANOVAs and regression analyses showed in Experiment 1 a significant improved cognitive performance (decreased ER and RTs) and higher self-perceived ranking in high-BAS participants. Moreover, their prefrontal activity was increased within the left side (alpha band decreasing). Conversely, in Experiment 2 a significant decreased cognitive performance (increased ER and RTs) and lower self-perceived ranking was observed in higher-BIS participants. Their prefrontal right activity was increased in comparison with higher BAS. The regression analyses confirmed the significant predictive role of alpha band modulation with respect of subjects' performance and self-perception of social ranking, differently for BAS/BIS components. The present results suggest that social status perception is directly modulated by cortical activity and personality correlates. Copyright © 2014 Elsevier Inc. All rights reserved.

Enrichment of common carp (Cyprinus carpio) diet with medlar (Mespilus germanica) leaf extract: Effects on skin mucosal immunity and growth performance.

PubMed

Hoseinifar, Seyed Hossein; Khodadadian Zou, Hassan; Kolangi Miandare, Hamed; Van Doan, Hien; Romano, Nicholas; Dadar, Maryam

2017-08-01

A feeding trial was performed to assess the effects of dietary Medlar (Mespilus germanica) leaf extract (MLE) on the growth performance, skin mucus non-specific immune parameters as well as mRNA levels of immune and antioxidant related genes in the skin of common carp (Cyprinus carpio) fingerlings. Fish were fed diets supplemented with graded levels (0, 0.25, 0.50, and 1.00%) of MLE for 49 days. The results revealed an improvement to the growth performance and feed conversion ratio in MLE fed carps (P < 0.05), regardless of the inclusion level. The immunoglobulin levels and interleukin 8 levels in the skin mucous and skin, respectively, revealed significant increment in fish fed 1% MLE (P < 0.05) in comparison with the other MLE treatments and control group. Also, feeding on 0.25% and 0.50% MLE remarkably increased skin mucus lysozyme activity (P < 0.05). However, there were no significant difference between MLE treated groups and control (P > 0.05) in case protease activity in the skin mucous or tumor necrosis factor alpha and interleukin 1 beta gene expression in the skin of carps (P > 0.05). The expression of genes encoding glutathione reductase and glutathione S-transferase alpha were remarkably increased in MLE fed carps compared to the control group (P < 0.05) while carp fed 0.50% or 1.00% MLE had significantly increased glutathione peroxidase expression in their skin (P < 0.05). The present results revealed the potentially beneficial effects of MLE on the mucosal immune system and growth performance in common carp fingerlings. Copyright © 2017 Elsevier Ltd. All rights reserved.

A dose-ranging study of the effects of mequitazine on actual driving, memory and psychomotor performance as compared to dexchlorpheniramine, cetirizine and placebo.

PubMed

Theunissen, E L; Vermeeren, A; van Oers, A C M; van Maris, I; Ramaekers, J G

2004-02-01

Mequitazine is a so-called 'non-sedative' second-generation antihistamine even though it has never been firmly established that this drug's sedative potential actually differs from that of the 'sedative' first-generation antihistamines. The present study compares the sedative effects of three doses of mequitazine on actual driving, psychomotor performance and memory with those of a first- and a second-generation antihistamine. Eighteen healthy volunteers received on separate days a single dose of 5, 10 and 15 mg mequitazine, 10 mg cetirizine, 6 mg dexchlorpheniramine and placebo. Drug effects were assessed using two actual driving tests (highway-driving test and car-following test), cognitive and psychometric tests (tracking, divided attention, memory, reasoning and critical flicker fusion), pupil size and questionnaires. Highway-driving data revealed an overall effect of Treatment on the standard deviation of lateral position (SDLP). Dexchlorpheniramine impaired driving performance as indicated by a significant rise in SDLP. Mequitazine significantly increased SDLP in a dose-related manner, but the separate dose effects failed to reach statistical significance. Divided attention performance was also affected by Treatment. Reaction time (RT) during mequitazine treatments increased in a dose-related manner and significantly differed from placebo at the highest dose. Subjects reported to be less alert after treatment with dexchlorpheniramine. Cetirizine did not affect performance in any of the tasks. It was concluded that mequitazine is mildly sedating. The effects of mequitazine are comparable to those of other second-generation antihistamines, in that it causes mild driving impairment, particularly at higher doses.

Online Lactation Education for Healthcare Providers: A Theoretical Approach to Understanding Learning Outcomes.

PubMed

Watkins, Amanda L; Dodgson, Joan E; McClain, Darya Bonds

2017-11-01

Breastfeeding competencies are not standardized in healthcare education for any of the health professions. A few continuing education/professional development programs have been implemented, but research regarding the efficacy of these programs is scarce. Research aim: After a 45-hour lactation course, (a) Does breastfeeding knowledge increase? (b) Do beliefs and attitudes about infant feeding improve? (c) Does perceived behavioral control over performance of evidence-based lactation support practices increase? and (d) Do intentions to carry out evidence-based lactation support practices increase? A nonexperimental pretest-posttest self-report survey design was conducted with a nonprobability sample of participants ( N = 71) in a lactation course. Theory of Planned Behavior variables were measured and a before-after course analysis was completed. Significantly higher scores were found on the posttests for knowledge, beliefs about breastfeeding scale, and the perceived behavioral control scale. Participants' self-efficacy increased after the course; their beliefs about social norms and their ability to effect change in their workplaces did not change significantly. Participants' intention to perform actions that are consistent with the evidence-based breastfeeding supportive behaviors increased significantly. Positive beliefs about formula feeding significantly increased; this was unexpected. The Theory of Planned Behavior provided a useful approach for examining more meaningful learning outcomes than the traditional knowledge and/or satisfaction outcomes. This study was the first to suggest that more meaningful learning outcomes are needed to evaluate lactation programs. However, it is not enough to educate healthcare providers in evidence-based practice; the places they practice must have the infrastructure to support evidence-based practice.

Fire-severity effects on plant-fungal interactions after a novel tundra wildfire disturbance: implications for arctic shrub and tree migration.

PubMed

Hewitt, Rebecca E; Hollingsworth, Teresa N; Stuart Chapin Iii, F; Lee Taylor, D

2016-05-11

Vegetation change in high latitude tundra ecosystems is expected to accelerate due to increased wildfire activity. High-severity fires increase the availability of mineral soil seedbeds, which facilitates recruitment, yet fire also alters soil microbial composition, which could significantly impact seedling establishment. We investigated the effects of fire severity on soil biota and associated effects on plant performance for two plant species predicted to expand into Arctic tundra. We inoculated seedlings in a growth chamber experiment with soils collected from the largest tundra fire recorded in the Arctic and used molecular tools to characterize root-associated fungal communities. Seedling biomass was significantly related to the composition of fungal inoculum. Biomass decreased as fire severity increased and the proportion of pathogenic fungi increased. Our results suggest that effects of fire severity on soil biota reduces seedling performance and thus we hypothesize that in certain ecological contexts fire-severity effects on plant-fungal interactions may dampen the expected increases in tree and shrub establishment after tundra fire.

Validity, Reliability, and Sensitivity of a Volleyball Intermittent Endurance Test.

PubMed

Rodríguez-Marroyo, Jose A; Medina-Carrillo, Javier; García-López, Juan; Morante, Juan C; Villa, José G; Foster, Carl

2017-03-01

To analyze the concurrent and construct validity of a volleyball intermittent endurance test (VIET). The VIET's test-retest reliability and sensitivity to assess seasonal changes was also studied. During the preseason, 71 volleyball players of different competitive levels took part in this study. All performed the VIET and a graded treadmill test with gas-exchange measurement (GXT). Thirty-one of the players performed an additional VIET to analyze the test-retest reliability. To test the VIET's sensitivity, 28 players repeated the VIET and GXT at the end of their season. Significant (P < .001) relationships between VIET distance and maximal oxygen uptake (r = .74) and GXT maximal speed (r = .78) were observed. There were no significant differences between the VIET performance test and retest (1542.1 ± 338.1 vs 1567.1 ± 358.2 m). Significant (P < .001) relationships and intraclass correlation coefficient (ICC) were found (r = .95, ICC = .96) for VIET performance. VIET performance increased significantly (P < .001) with player performance level and was sensitive to fitness changes across the season (1458.8 ± 343.5 vs 1581.1 ± 334.0 m, P < .01). The VIET may be considered a valid, reliable, and sensitive test to assess the aerobic endurance in volleyball players.

The influence of polymer purification on photovoltaic device performance of a series of indacenodithiophene donor polymers.

PubMed

Ashraf, Raja Shahid; Schroeder, Bob C; Bronstein, Hugo A; Huang, Zhenggang; Thomas, Stuart; Kline, R Joseph; Brabec, Christoph J; Rannou, Patrice; Anthopoulos, Thomas D; Durrant, James R; McCulloch, Iain

2013-04-11

A series of low bandgap indacenodithiophene polymers is purified by recycling SEC in order to isolate narrow polydispersity fractions. This additional purification step is found to have a significant beneficial influence on the solar cell performance and the reasons for this performance increase are investigated. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Muscular contribution to low-back loading and stiffness during standard and suspended push-ups.

PubMed

Beach, Tyson A C; Howarth, Samuel J; Callaghan, Jack P

2008-06-01

Push-up exercises are normally performed to challenge muscles that span upper extremity joints. However, it is also recognized that push-ups provide an effective abdominal muscle challenge, especially when the hands are in contact with a labile support surface. The purpose of this study was to compare trunk muscle activation levels and resultant intervertebral joint (IVJ) loading when standard and suspended push-ups were performed, and to quantify and compare the contribution of trunk muscles to IVJ rotational stiffness in both exercises. Eleven recreationally trained male volunteers performed sets of standard and suspended push-ups. Upper body kinematic, kinetic, and EMG data were collected and input into a 3D biomechanical model of the lumbar torso to quantify lumbar IVJ loading and the contributions of trunk muscles to IVJ rotational stiffness. When performing suspended push-ups, muscles of the abdominal wall and the latissimus dorsi were activated to levels that were significantly greater than those elicited when performing standard push-ups (p<.05). As a direct result of these increased activation levels, model-predicted muscle forces increased and consequently led to significantly greater mean (p=.0008) and peak (p=.0012) lumbar IVJ compressive forces when performing suspended push-ups. Also directly resulting from the increased activation levels of the abdominal muscles and the latissimus dorsi during suspended push-ups was increased muscular contribution to lumbar IVJ rotational stiffness (p<.05). In comparison to the standard version of the exercise, suspended push-ups appear to provide a superior abdominal muscle challenge. However, for individuals unable to tolerate high lumbar IVJ compressive loads, potential benefits gained by incorporating suspended push-ups into their resistance training regimen may be outweighed by the risk of overloading low-back tissues.

Dietary supplementation of biofloc influences growth performance, physiological stress, antioxidant status and immune response of juvenile sea cucumber Apostichopus japonicus (Selenka).

PubMed

Chen, Jinghua; Ren, Yichao; Wang, Guodong; Xia, Bin; Li, Yuquan

2018-01-01

Bioflocs are rich in various probiotics and bioactive compounds, which play an important role in improving growth and health status of aquatic organisms. A 60-day experiment was conducted to investigate the effects of dietary supplementation of biofloc on growth performance, digestive enzyme activity, physiological stress, antioxidant status, expression of immune-related genes and disease resistance of sea cucumber Apostichopus japonicus. Juvenile sea cucumbers were fed five experimental diets containing graded levels of biofloc from 0% to 20% (referred as B0, B5, B10, B15 and B20, respectively). The results showed that the sea cucumbers at dietary supplementation levels of 10%-15% biofloc had significantly higher specific growth rate (SGR) compared to control group (diet B0). Digestive enzyme activity increased with the increasing of dietary biofloc level, while no significant difference was found between diets B15 and B20. Dietary supplementation of biofloc also had significant influences on physiological stress parameters except for lactate. There was no significant discrepancy in total coelomocytes counts (TCC) in coelomic fluid of sea cucumber between the treatments. Phagocytosis and respiratory burst of cellular immune at 15% and 20% biofloc levels were significantly higher than those of control group. Significant increases in superoxide dismutase (SOD), total nitric oxide synthase (T-NOS), lysozyme (LSZ), acid phosphatase (ACP) and alkaline phosphatase (AKP) activities of sea cucumber were found at highest dietary supplementation level of 20% biofloc. The expression patterns of immune-related genes (i.e., Hsp90, Hsp70, p105, Rel, NOS and LSZ) in tissues of sea cucumber were analyzed between the experimental diets, and a general trend of up-regulation was observed at higher biofloc levels. Furthermore, dietary 10%-20% biofloc significantly reduced cumulative mortality of sea cucumber after being challenged with Vibrio splendidus. In conclusion, dietary supplementation of biofloc could improve growth performance of A. japonicus, by increasing digestive enzyme activity, releasing physiological stress, enhancing immune response and disease resistance of sea cucumber. The suitable supplemental level of approximately 15% biofloc was recommended in the present study. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of fuel properties on performance of a single aircraft turbojet combustor

NASA Technical Reports Server (NTRS)

Butze, H. F.; Ehlers, R. C.

1975-01-01

The performance of a single-can JT8D combustor was investigated with a number of fuels exhibiting wide variations in chemical composition and volatility. Performance parameters investigated were combustion efficiency, emissions of CO, unburned hydrocarbons and NOx, as well as liner temperatures and smoke. At the simulated idle condition no significant differences in performance were observed. At cruise, liner temperatures and smoke increased sharply with decreasing hydrogen content of the fuel. No significant differences were observed in the performance of an oil-shale derived JP-5 and a petroleum-based Jet A fuel except for emissions of NOx which were higher with the oil-shale JP-5. The difference is attributed to the higher concentration of fuel-bound nitrogen in the oil-shale JP-5.

Effect of Active Workstation on Energy Expenditure and Job Performance: A Systematic Review and Meta-analysis.

PubMed

Cao, Chunmei; Liu, Yu; Zhu, Weimo; Ma, Jiangjun

2016-05-01

Recently developed active workstation could become a potential means for worksite physical activity and wellness promotion. The aim of this review was to quantitatively examine the effectiveness of active workstation in energy expenditure and job performance. The literature search was conducted in 6 databases (PubMed, SPORTDiscuss, Web of Science, ProQuest, ScienceDirect, and Scopuse) for articles published up to February 2014, from which a systematic review and meta-analysis was conducted. The cumulative analysis for EE showed there was significant increase in EE using active workstation [mean effect size (MES): 1.47; 95% confidence interval (CI): 1.22 to 1.72, P < .0001]. Results from job performance indicated 2 findings: (1) active workstation did not affect selective attention, processing speed, speech quality, reading comprehension, interpretation and accuracy of transcription; and (2) it could decrease the efficiency of typing speed (MES: -0.55; CI: -0.88 to -0.21, P < .001) and mouse clicking (MES: -1.10; CI: -1.29 to -0.92, P < .001). Active workstation could significantly increase daily PA and be potentially useful in reducing workplace sedentariness. Although some parts of job performance were significantly lower, others were not. As a result there was little effect on real-life work productivity if we made a good arrangement of job tasks.

Ontogenetic change in relative performance of allozyme genotypes influences detection of heterosis in the earthworm Eisenia andrei.

PubMed

McElroy, T C; Diehl, W J

2005-02-01

The effect of ontogeny on relationships between allozyme genotypes and fresh weight was measured weekly throughout the life history of the earthworm Eisenia andrei to test the hypothesis that there is an ontogenetic component to variation in such relationships. Two of six allozyme loci showed a significant increase in apparent heterosis with ontogeny, while one locus showed a significant decrease in apparent heterosis. Three loci showed a significant decrease in the performance of common homozygotes with ontogeny. Patterns of relative genotypic performance varied among loci, but the cumulative effect was an increase in apparent allozyme heterosis later in ontogeny coinciding with a series of positive relationships between multilocus heterozygosity and fresh weight. The results could not be used to determine whether these patterns were caused by selection acting on the loci directly or on loci tightly linked to allozyme loci. However, because the same individuals were used throughout this study and thus allele frequencies and heterozygote deficiency were constant, the presence of both ontogenetic effects and differences in such patterns among loci is not compatible with a general inbreeding effect. Examining relative genotypic performance repetitively using the same individuals through ontogeny or in different environments is a very powerful experimental design for testing the effects of inbreeding or other populational factors.

Shooting performance is related to forearm temperature and hand tremor size.

PubMed

Lakie, M; Villagra, F; Bowman, I; Wilby, R

1995-08-01

The changes in postural tremor of the hand and the subsequent effect on shooting performance produced by moderate cooling and heating of the forearm were studied in six subjects. Cooling produced a large decrease in tremor size of the ipsilateral hand, whereas warming the limb produced an increase in tremor size. Cooling or warming the forearm did not change the peak frequency of tremor significantly, which was quite stable for each subject. The improvement in shooting performance after cooling the forearm, as measured by grouping pattern of the shots, reached statistical significance and warming caused a significant worsening. This measure of performance was shown to correlate (r = 0.776) inversely with tremor size. The causes and implications of these changes are discussed. It is suggested that local cooling may be useful for people who wish temporarily to reduce tremor in order to improve dexterity for shooting and for other purposes.

Long-term exercise training in persons with spinal cord injury: effects on strength, arm ergometry performance and psychological well-being.

PubMed

Hicks, A L; Martin, K A; Ditor, D S; Latimer, A E; Craven, C; Bugaresti, J; McCartney, N

2003-01-01

Randomized controlled trial of exercise training in persons with spinal cord injury. The purpose of this study was to examine the effects of 9 months of twice-weekly exercise training on strength, arm ergometry performance, and indices of psychological well-being and quality of life. Centre for Health Promotion and Rehabilitation, McMaster University, Hamilton, Ontario, Canada. Thirty-four men and women (aged 19-65 years) with traumatic spinal cord injury (C4-L1; ASIA A-D) of 1-24 years duration volunteered to participate, and were randomized into exercise (EX; n=21) and control (CON; n=13) groups. Twenty-three subjects (11 EX; 12 CON) successfully completed the 9-month study. Subjects were assessed for one repetition maximum (1RM) strength, arm ergometry performance, and several indices of quality of life and psychological well-being at baseline, 3, 6, and 9 months. At baseline, there were no significant differences between groups in age, submaximal arm ergometry performance, muscle strength, or psychological well-being. Following training, the EX group had significant increases in submaximal arm ergometry power output (81%; P<0.05), and significant increases in upper body muscle strength (19-34%; P<0.05); no significant changes occurred in CON. Participants in EX reported significantly less pain, stress and depression after training, and scored higher than CON in indices of satisfaction with physical function, level of perceived health and overall quality of life (P<0.05). Exercise adherence (per cent of prescribed sessions attended) in those subjects who completed the 9 months of training was 82.5%. These results demonstrate that long-term twice-weekly exercise training in this population is feasible, and results in significant gains in both physical and psychological well-being.

Adrenergic System Activation Mediates Changes in Cardiovascular and Psychomotoric Reactions in Young Individuals after Red Bull© Energy Drink Consumption

PubMed Central

Cavka, Ana; Stupin, Marko; Panduric, Ana; Plazibat, Ana; Cosic, Anita; Rasic, Lidija; Debeljak, Zeljko; Martinovic, Goran; Drenjancevic, Ines

2015-01-01

Objectives. To assess the effect of Red Bull© on (1) blood glucose and catecholamine levels, (2) cardiovascular and respiratory function changes before, during, and after exercise, (3) reaction time, (4) cognitive functions, and (5) response to mental stress test and emotions in young healthy individuals (N=38). Methods. Heart rate (HR) and arterial blood pressure (ABP), blood glucose, adrenaline, and noradrenalin plasma levels were measured before and after Red Bull© intake. Participants were subjected to 4 different study protocols by randomized order, before and 30 minutes after consumption of 500 mL of Red Bull©. Results. Mean ABP and HR were significantly increased at rest after Red Bull© intake. Blood glucose level and plasma catecholamine levels significantly increased after Red Bull© consumption. Heart rate, respiration rate, and respiratory flow rate were significantly increased during exercise after Red Bull© consumption compared to control condition. Intake of Red Bull© significantly improved reaction time, performance in immediate memory test, verbal fluency, and subject's attention as well as performance in mental stress test. Conclusion. This study demonstrated that Red Bull© has beneficial effect on some cognitive functions and effect on cardiovascular and respiratory system at rest and during exercise by increasing activity of the sympathetic nervous system. PMID:26124829

Protective effects of cultured and fermented ginseng extracts against scopolamine-induced memory loss in a mouse model.

PubMed

Han, Song-Hee; Kim, Sung-June; Yun, Young Won; Nam, Sang Yoon; Lee, Hu-Jang; Lee, Beom-Jun

2018-03-01

This study was performed to investigate the effect of a concentrate of fermented wild ginseng root culture (HLJG0701) on memory improvement in the scopolamine (SPL)-induced memory-deficient mouse model. Eight-week-old male ICR mice were used to evaluate the protective effect of HLJG0701 against the SPL-induced memory loss animal model. The Morris water maze test, which measures hippocampus-dependent learning ability, and the Y-maze test, a short-term memory assessment test, were performed and related markers were analyzed. HLJG0701-treated groups displayed significantly reduced acetylcholinesterase activity and increased acetylcholine level compared with the SPL-administered group (SPL-G) ( P <0.05). In the Y-maze test, the spontaneous alternation in al HLJG0711-treated groups was significantly increased compared with that in SPL-G ( P <0.05). In the Morris water maze test, the escape latency and time spent in the target quadrant in all HLJG0701-treated groups were significantly decreased and increased, respectively, compared with those in SPL-G ( P <0.05). In addition, the brain-derived neurotrophic factor level in groups treated with HLJG0701 300 and 600 mg/kg body weight was significantly increased compared with that in SPL-G ( P <0.05). These results suggest that the HLJG0701 may protect against memory loss by inhibiting acetylcholinesterase activity and preventing acetylcholine deficiency.

The impact of green roof ageing on substrate characteristics and hydrological performance

NASA Astrophysics Data System (ADS)

De-Ville, Simon; Menon, Manoj; Jia, Xiaodong; Reed, George; Stovin, Virginia

2017-04-01

Green roofs contribute to stormwater management through the retention of rainfall and the detention of runoff. However, there is very limited knowledge concerning the evolution of green roof hydrological performance with system age. This study presents a non-invasive technique which allows for repeatable determination of key substrate characteristics over time, and evaluates the impact of observed substrate changes on hydrological performance. The physical properties of 12 green roof substrate cores have been evaluated using non-invasive X-ray microtomography (XMT) imaging. The cores comprised three replicates of two contrasting substrate types at two different ages: unused virgin samples; and 5-year-old samples from existing green roof test beds. Whilst significant structural differences (density, pore and particle sizes, tortuosity) between virgin and aged samples of a crushed brick substrate were observed, these differences did not significantly affect hydrological characteristics (maximum water holding capacity and saturated hydraulic conductivity). A contrasting substrate based upon a light expanded clay aggregate experienced increases in the number of fine particles and pores over time, which led to increases in maximum water holding capacity of 7%. In both substrates, the saturated hydraulic conductivity estimated from the XMT images was lower in aged compared with virgin samples. Comparisons between physically-derived and XMT-derived substrate hydrological properties showed that similar values and trends in the data were identified, confirming the suitability of the non-invasive XMT technique for monitoring changes in engineered substrates over time. The observed effects of ageing on hydrological performance were modelled as two distinct hydrological processes, retention and detention. Retention performance was determined via a moisture-flux model using physically-derived values of virgin and aged maximum water holding capacity. Increased water holding capacity with age increases the potential for retention performance. However, seasonal variations in retention performance greatly exceed those associated with the observed age-related increases in water holding capacity (+72% vs +7% respectively). Detention performance was determined via an unsaturated-flow finite element model, using van Genuchten parameters and XMT-derived values of saturated hydraulic conductivity. Reduced saturated hydraulic conductivity increases detention performance. For a 1-hour 30-year design storm, the peak runoff was found to be 33% lower for the aged brick-based substrate compared with its virgin counterpart.

Self-reported study habits for enhancing medical students’ performance in the National Medical Unified Examination

PubMed Central

Idris, Amr; Al Saadi, Tareq; Edris, Basel; Sawaf, Bisher; Zakaria, Mhd. Ismael; Alkhatib, Mahmoud; Turk, Tarek

2016-01-01

Background: The National Medical Unified Examination (NMUE) is currently required for graduation, joining postgraduate medical training, and practicing medicine in Syria. Objective: To investigate self-reported study habits that correlate with high performance on the NMUE. Methods: First through 3rd year residents at the three main hospitals in Damascus, Syria, were asked to complete a retrospective cross-sectional survey investigating their study habits and previous scores. Results: Significantly higher score was associated with >15 study h/day and allocating 1–40% of study time for practicing questions. Mean NMUE score was not significantly different in relation to preparation months for examination or for those who reported spending all their time studying alone compared with spending any amount of time in a group setting. Scores of 231–240 on the Syrian scientific high school exam correlated with significantly higher NMUE performance compared with fewer scores, except scores of 221–230. For every 10 point increase in medical school cumulative grades, the NMUE score increased 3.6 (95% confidence interval 2.5–4.8). Conclusion: The NMUE score was significantly affected by hours spent studying per day, number of practice questions completed, percentage of study time allocated for doing questions, Syrian scientific high school exam scores, and the cumulative medical school class grades. It was not significantly affected by preparation months or studying in a group setting. More studies are needed to further describe and investigate the factors that might affect performance in the NMUE. PMID:27144140

The effects of performing a one-legged bridge with hip abduction and use of a sling on trunk and lower extremity muscle activation in healthy adults.

PubMed

Choi, Kyuju; Bak, Jongwoo; Cho, Minkwon; Chung, Yijung

2016-09-01

[Purpose] This study investigated the changes in the muscle activities of the trunk and lower limbs of healthy adults during a one-legged bridge exercise using a sling, and with the addition of hip abduction. [Subjects and Methods] Twenty-seven healthy individuals participated in this study (14 males and 13 females). The participants were instructed to perform the bridge exercises under five different conditions. Trunk and lower limb muscle activation of the erector spinae (ES), external oblique (EO), gluteus maximus (GM), and biceps femoris (BF) was measured using surface electromyography. Data analysis was performed using the mean scores of three trials performed under each condition. [Results] There was a significant increase in bilateral EO and contralateral GM with the one-legged bridge compared with the one-legged bridge with sling exercise. Muscle activation of the ipsilateral GM and BF was significantly less during the one-legged bridge exercise compared to the one-legged bridge with sling exercise, and was significantly greater during the one-legged bridge with hip abduction compared to the one-legged bridge exercise. The muscle activation of the contralateral GM and BF was significantly greater with the one-legged bridge with hip abduction compared to the general bridge exercise. [Conclusion] With the one-legged bridge with hip abduction, the ipsilateral EO, GM and BF muscle activities were significantly greater than those of the one-legged bridge exercise. The muscle activation of all trunk and contralateral lower extremity muscles increased with the bridge with sling exercises compared with general bridge exercises.

Factors associated with perioperative mortality in dogs with surgically managed gastric dilatation-volvulus: 137 cases (1988-1993).

PubMed

Brourman, J D; Schertel, E R; Allen, D A; Birchard, S J; DeHoff, W D

1996-06-01

To evaluate factors associated with perioperative mortality in dogs with gastric dilatation-volvulus and to determine the influence of treatment differences between university and private specialty practices on outcome. Retrospective analysis of medical records. 137 dogs with gastric dilatation-volvulus. Signalment; frequency of preoperative and postoperative treatments and complications; intraoperative findings; surgical technique; and hematologic, serum biochemical, and electrocardiographic results were recorded, evaluated for association with mortality, and compared between institutions. Mortality did not differ between institutions, and overall mortality was 18% (24/137). Surgical techniques differed between institutions, but were not associated with mortality. Gastric necrosis was associated with significantly higher mortality (46%; 13/28). When partial gastrectomy or splenectomy was performed, mortality (35 and 32% or 8/23 and 10/31, respectively) was significantly increased. Splenectomy was performed in 11 of 23 dogs requiring partial gastrectomy, and when both procedures were performed, mortality (55%; 6/11) was significantly increased. Preoperative cardiac arrhythmias were associated with significantly higher mortality (38%; 6/16). Mortality in dogs > 10 years old was not significantly greater than that in younger dogs. Patient management differences between practices did not seem to influence survival in dogs with surgically managed gastric dilatation-volvulus. Signalment, including age, did not influence mortality. Gastric necrosis, gastric resection, splenectomy, and preoperative cardiac arrhythmias were associated with mortality > 30%.

Alfacalcidol improves muscle power, muscle function and balance in elderly patients with reduced bone mass.

PubMed

Schacht, E; Ringe, Johann D

2012-01-01

We investigated the effect of daily therapy with 1 mcg alfacalcidol (Doss(®)-TEVA/AWD-pharma) on muscle power, muscle function, balance performance and fear of falls in an open, multi-centered, uncontrolled, prospective study on a cohort of patients with reduced bone mass. Among the 2,097 participants, 87.1% were post-menopausal women and 12.9% were men. Mean age was 74.8 years and mean body mass index (BMI) 26.3 kg/m². A total of 75.3% of the study population had osteoporosis, 81% a diagnosis of "increased risk of falls" and 70.1% had a creatinine clearance (CrCl) of <65 ml/min. Participants underwent muscle function and muscle power tests at onset and after 3 and 6 months: the timed up and go test (TUG) and the chair rising test (CRT). At baseline and after 6 months, participants performed the tandem gait test (TGT) and filled out a questionnaire evaluating fear of falling. Successful performance in the muscle tests is associated with a significantly lower risk of falls and non-vertebral fractures in elderly patients (successful test performance: TUG ≤ 10 s (sec), CRT ≤ 10 s, TGT ≥ 8 steps). A significant improvement in the performance of the two muscle tests was proved already after 3 months of treatment with alfacalcidol and further increased by the end of the therapeutic intervention. There were significant increases in the number of participants able to successfully perform the tests: 24.6% at baseline and 46.3% at the end of trial for the TUG (P < 0.0001) and 21.7% at baseline and 44.2% at the end for the CRT test (P = 0.0001). The mean time used for the TUG was decreased by 3.0 s from the average onset value of 17.0 s and by 3.1 s from the initial average 16.5 s for the CRT. The percentage of participants able to perform the balance test (TGT) increased from 36.0% at onset to 58.6% at the end of the trial (P < 0.0001). An increased fear of falling was reduced by the end of the study in 74.4% of the patients. Throughout the study, there were 26 adverse drug reactions in 11 out of 2,097 patients (incidence 0.52%). No serious adverse drug reactions and no cases of hypercalcemia were documented. We conclude that treatment with alfacalcidol is safe, increases muscle power, muscle function and balance and reduces fear of falls. The significant improvement in the three muscle and balance tests and fear of falls may have a preventative effect on falls and fractures. We suggest that the quantitative risk tests used in this study could be reliable surrogate parameters for the risk of falls and fractures in elderly patients.

The blood antioxidant defence capacity during intermittent hypoxic training in elite swimmers

PubMed Central

Poprzęcki, S; Zając, A; Karpiński, J; Wilk, R; Bril, G; Maszczyk, A; Toborek, M

2016-01-01

The main objective of this study was to examine the chronic effect of simulated intermittent normobaric hypoxia on blood antioxidant defence capacity in swimmers. The study included 14 male and 14 female competitive swimmers performing part of land training under simulated intermittent normobaric hypoxia (O2 = 15.5%) or in normoxia. Land interval training took place twice per week, with a total of 8 training units during the study, performed with individualized intensity. The activities of blood antioxidant enzymes did not change significantly during the first and last training unit in the hypoxic and normoxic group. However, when comparing individual variables a significant effect of exercise was observed on GPx an CAT activities, whereas training units significantly differentiated GPx and GR activities. The oxygen conditions and gender had a significant influence on CAT activity. The total antioxidant capacity was not significantly affected. Only in male swimmers from the hypoxic group did the training significantly increase resting levels of MDA. In conclusion, training in normobaric hypoxia was not an adequate stimulus for the excessive response of the antioxidant defence system, despite increased oxidative stress in these conditions. PMID:28090139

Pain neurophysiology education improves cognitions, pain thresholds, and movement performance in people with chronic whiplash: a pilot study.

PubMed

Van Oosterwijck, Jessica; Nijs, Jo; Meeus, Mira; Truijen, Steven; Craps, Julie; Van den Keybus, Nick; Paul, Lorna

2011-01-01

Chronic whiplash is a debilitating condition characterized by increased sensitivity to painful stimuli, maladaptive illness beliefs, inappropriate attitudes, and movement dysfunctions. Previous work in people with chronic low back pain and chronic fatigue syndrome indicates that pain neurophysiology education is able to improve illness beliefs and attitudes as well as movement performance. This single-case study (A-B-C design) with six patients with chronic whiplash associated disorders (WAD) was aimed at examining whether education about the neurophysiology of pain is accompanied by changes in symptoms, daily functioning, pain beliefs, and behavior. Periods A and C represented assessment periods, while period B consisted of the intervention (pain neurophysiology education). Results showed a significant decrease in kinesiophobia (Tampa Scale for Kinesiophobia), the passive coping strategy of resting (Pain Coping Inventory), self-rated disability (Neck Disability Index), and photophobia (WAD Symptom List). At the same time, significantly increased pain pressure thresholds and improved pain-free movement performance (visual analog scale on Neck Extension Test and Brachial Plexus Provocation Test) were established. Although the current results need to be verified in a randomized, controlled trial, they suggest that education about the physiology of pain is able to increase pain thresholds and improve pain behavior and pain-free movement performance in patients with chronic WAD.

Anxiety-induced plasma norepinephrine augmentation increases reactive oxygen species formation by monocytes in essential hypertension.

PubMed

Yasunari, Kenichi; Matsui, Tokuzo; Maeda, Kensaku; Nakamura, Munehiro; Watanabe, Takanori; Kiriike, Nobuo

2006-06-01

An association between anxiety and depression and increased blood pressure (BP) and cardiovascular disease risk has not been firmly established. We examined the hypothesis that anxiety and depression lead to increased plasma catecholamines and to production of reactive oxygen species (ROS) by mononuclear cells (MNC) in hypertensive individuals. We also studied the role of BP in this effect. In Protocol 1, a cross-sectional study was performed in 146 hypertensive patients to evaluate whether anxiety and depression affect BP and ROS formation by MNC through increasing plasma catecholamines. In Protocol 2, a 6-month randomized controlled trial using a subtherapeutic dose of the alpha(1)-adrenergic receptor antagonist doxazosin (1 mg/day) versus placebo in 86 patients with essential hypertension was performed to determine whether the increase in ROS formation by MNC was independent of BP. In Protocol 1, a significant relationship was observed between the following: trait anxiety and plasma norepinephrine (r = 0.32, P < .01); plasma norepinephrine and ROS formation by MNC (r = 0.36, P < .01); and plasma norepinephrine and systolic, diastolic, and mean BP (r = 0.17, P = .04; r = 0.26, P = .02; r = 0.23, P < .01, respectively). In Protocol 2, subtherapeutic doxazosin treatment (1 mg/day) had no significant effect on BP. However doxazosin significantly decreased ROS formation by MNC compared with placebo (P < .01). Trait anxiety may increase plasma norepinephrine and increase ROS formation by MNC independent of BP in hypertensive patients.

Pre-task music improves swimming performance.

PubMed

Smirmaul, B P; Dos Santos, R V; Da Silva Neto, L V

2015-12-01

The purpose of this study was to investigate the effects of pre-task music on swimming performance and other psychological variables. A randomized counterbalanced within-subjects (experimental and control condition) design was employed. Eighteen regional level male swimmers performed two 200-m freestyle swimming time trials. Participants were exposed to either 5 minutes of self-selected music (pre-task music condition) or 5 minutes of silence (control condition) and, after 1 minute, performed the swimming task. Swimming time was significantly shorter (-1.44%) in the pre-task music condition. Listening to pre-task music increased motivation to perform the swimming task, while arousal remained unchanged. While fatigue increased after the swimming task in both conditions, vigor, ratings of perceived exertion and affective valence were unaltered. It is concluded, for the first time, that pre-task music improves swimming performance.

Memory performance in abstinent 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") users.

PubMed

Groth-Marnat, Gary; Howchar, Hennedy; Marsh, Ali

2007-02-01

Research with animals and humans has suggested that acute and subacute use of 3,4-methylenedioxymethamphetamine (MDMA "ecstasy") may lead to memory impairment. However, research is limited by (1) low power due to small sample sizes, (2) the possible confound of polydrug use, and (3) the failure to consider intelligence as a covariate. The present study compared the memory performance on the Wechsler Memory Scale-III of 26 abstinent (2-wk. minimum) recreational MDMA users with 26 abstinent (2-wk. minimum) recreational polydrug users. Despite significantly greater polydrug use amongst these MDMA users, no significant group differences in memory were observed. Regression of total lifetime amount of MDMA use also did not predict memory performance after accounting for intelligence. In addition, the length of time since abstinence (at least 2 wk.) was not associated with an increase in memory performance. Greater total lifetime cocaine use, rather than total lifetime MDMA use, was significantly associated with greater decrements in General Memory and Delayed Verbal Memory performance.

Time estimation as a secondary task to measure workload. [attention sharing effect on operator performance

NASA Technical Reports Server (NTRS)

Hart, S. G.

1975-01-01

Variation in the length of time productions and verbal estimates of duration was investigated to determine the influence of concurrent activity on operator time perception. The length of 10-, 20-, and 30-sec intervals produced while performing six different compensatory tracking tasks was significantly longer, 23% on the average, than those produced while performing no other task. Verbal estimates of session duration, taken at the end of each of 27 experimental sessions, reflected a parallel increase in subjective underestimation of the passage of time as the difficulty of the task performed increased. These data suggest that estimates of duration made while performing a manual control task provide stable and sensitive measures of the workload imposed by the primary task, with minimal interference.

The dumbest experiment in space. [problems in laboratory apparatus adaption to space environment

NASA Technical Reports Server (NTRS)

Prouty, C. R.

1981-01-01

A simple conceptual experiment is used to illustrate (1) the fundamentals of performing an experiment, including the theoretical concept, the experiment design, the performance of the experiment, and the recording of observations; (2) the increasing challenges posed by performance of the same experiment in a location remote from the experimenter, such as additional planning and equipment and their associated cost increases; and (3) the significant growth of difficulties to be overcome when the simple experiment is performed in a highly restrictive environment, such as a spacecraft in orbit, with someone else remotely operating the experiment. It is shown that performing an experiment in the remote, hostile environment of space will pose difficulties equaling or exceeding those of the experiment itself, entailing mastery of a widening range of disciplines.

The meat quality and growth performance in broiler chickens fed diet with cinnamon powder.

PubMed

Sang-Oh, Park; Chae-Min, Ryu; Byung-Sung, Park; Jong, Hwangbo

2013-01-01

The aim of the study was to investigate the feeding effect of diets containing 3, 5 and 7% of cinnamon powder on meat quality and growth performance in broiler chickens. The chicken meat quality and growth performance in broiler chickens fed diets containing cinnamon powder increased significantly (P < 0.05) when compared to the control group. However, the TBARS of the meat of chickens fed diets containing cinnamon powder decreased significantly (P < 0.05) when compared to the control group. These findings suggest that the cinnamon powder can improve the shelf life and quality of chicken meat with maximize the productivity of broiler chickens.

The effect of dietary fructooligosaccharide supplementation on growth performance, intestinal morphology, and immune responses in broiler chickens challenged with Salmonella Enteritidis lipopolysaccharides.

PubMed

Shang, Yue; Regassa, Alemu; Kim, Ji Hyuk; Kim, Woo Kyun

2015-12-01

This study was conducted to examine the effects of fructooligosaccharide (FOS) supplementation on growth performance, lymphoid organ weight, intestinal morphology, and immunological status in broilers (n=180) challenged with Salmonella Enteritidis lipopolysaccharides (LPS). Birds were randomly assigned into a 3×2 factorial arrangement that included 1) 3 dietary treatments from d one to 21: positive control (PC), wheat-corn-soybean meal based diet contained antibiotics (virginiamycin and monensin); negative control (NC), as PC without antibiotics; and NC+FOS, as NC supplemented with 0.5% FOS, and 2) 2 intraperitoneal injections: 2 mg/kg Salmonella Enteritidis LPS or sterile phosphate buffered saline (PBS) on d 21. Growth performance and relative lymphoid organ weight were not significantly different among the treatments. Villus height, crypt depth, and total mucosa thickness were significantly increased (P<0.05) in the ileum of broiler chickens fed NC+FOS when compared to PC and NC. Birds in NC+FOS treatment had reduced heterophil but increased monocyte count when compared to NC (P<0.05). Significant diet×challenge interaction was observed on natural IgY levels (P<0.0001), and a significant dietary effect was observed on specific IgY levels in chickens fed NC+FOS (P=0.003). Supplementation of FOS also increased the expression of interleukin (IL)-1ß, -10, and interferon (IFN)-γ mRNA in the ileum of the birds. In summary, Salmonella Enteritidis LPS challenge established significant differences in the immune responses in broiler chickens. FOS supplementation increased ileal mucosa thickness and elevated the expressions of certain cytokine genes. It also led to the alteration of leukocyte compositions and serum IgY levels in response to LPS challenge, suggesting FOS supplementation may be effective to induce protective outcomes in gut health and immunity of broiler chickens. © 2015 Poultry Science Association Inc.

Maternal request: a reason for rising rates of cesarean section?

PubMed

Kottmel, Andrea; Hoesli, Irene; Traub, Rahel; Urech, Corinne; Huang, Dorothy; Leeners, Brigitte; Tschudin, Sibil

2012-07-01

The rising rate of cesarean sections (CS), especially those on maternal request, is an important obstetric care issue. The aim of this two-point cross-sectional study was to evaluate the prevalence of CS and their indications. We performed a retrospective chart review of the indications of all CS performed at a tertiary care clinic in Switzerland in 2002 and 2008. Chi-square, Student's t and Mann-Whitney U tests were performed to identify significant differences. The number of CS rose from 23.3% (371 out of 1,594 total life births) in 2002 to 27.5% (513 out of 1,866) in 2008 (p = 0.005). Of all deliveries, the rate of CS on maternal request and, among these, especially those requested after previous CS, increased significantly (2.1 vs. 5.1% and 0.3 vs. 1.2%, respectively). The number of CS due to previous traumatic birth experience nearly doubled (0.7 vs. 1.2%, not significant). Maternal and fetal complications were rare but not negligible in the subset of low-risk patients requesting CS. The study demonstrated a significant increase in CS on maternal request, especially in case of previous CS. The findings of this study support the need for specific counseling strategies for women requesting delivery by CS.

Tibial Tray Thickness Significantly Increases Medial Tibial Bone Resorption in Cobalt-Chromium Total Knee Arthroplasty Implants.

PubMed

Martin, J Ryan; Watts, Chad D; Levy, Daniel L; Miner, Todd M; Springer, Bryan D; Kim, Raymond H

2017-01-01

Stress shielding is an uncommon complication associated with primary total knee arthroplasty. Patients are frequently identified radiographically with minimal clinical symptoms. Very few studies have evaluated risk factors for postoperative medial tibial bone loss. We hypothesized that thicker cobalt-chromium tibial trays are associated with increased bone loss. We performed a retrospective review of 100 posterior stabilized, fixed-bearing total knee arthroplasty where 50 patients had a 4-mm-thick tibial tray (thick tray cohort) and 50 patients had a 2.7-mm-thick tibial tray (thin tray cohort). A clinical evaluation and a radiographic assessment of medial tibial bone loss were performed on both cohorts at a minimum of 2 years postoperatively. Mean medial tibial bone loss was significantly higher in the thick tray cohort (1.07 vs 0.16 mm; P = .0001). In addition, there were significantly more patients with medial tibial bone loss in the thick tray group compared with the thin tray group (44% vs 10%, P = .0002). Despite these differences, there were no statistically significant differences in range of motion, knee society score, complications, or revision surgeries performed. A thicker cobalt-chromium tray was associated with significantly more medial tibial bone loss. Despite these radiographic findings, we found no discernable differences in clinical outcomes in our patient cohort. Further study and longer follow-up are needed to understand the effects and clinical significance of medial tibial bone loss. Copyright © 2016 Elsevier Inc. All rights reserved.

The effectiveness of an integrated conceptual approach to teaching middle school science: A mixed methods investigation

NASA Astrophysics Data System (ADS)

Frampton, Susan K.

This study was designed to compare the effectiveness of using traditional and integrated instructional strategies to increase student understanding of the core concepts of energy. There are mixed messages in the literature as to the success of using an integrated approach to teach science content, despite suggestions its use improves student achievement and attitudes toward science. This study used a mixed-method approach. The quantitative portion was a quasi-experimental non-equivalent control group design, and the qualitative portion included teacher journals, teacher interviews and student journals. There were three teacher participants, two in the treatment group from a district in Sussex County, Delaware. The third teacher participant, from a different district in Sussex County, Delaware was in the control group. The treatment group consisted of 180 students and the control group consisted of 124 students. The results of this study show that the treatment group had significantly less anxiety in science following the treatment, than students in the control group. The F value of 10.89 was significant at p = 0.001. Students in the treatment group also had more enjoyment of and motivation in science than did students in the control group. The F value of 25.025 was significant at a p = 0.000 for the subscale enjoyment of science. The F value of 14.1 was significant at a p = 0.000 for the subscale of motivation in science. Students in the treatment group performed significantly better on the achievement tests, the Integrated Summative Energy Assessment (ISEA) and the science portion of the Delaware State Testing Program (DSTP). The treatment group performed significantly better on the ISEA than did the control group, with an F value of 407.7 significant at p = 0.000. The treatment group performed significantly better on the science DSTP than the control group, with an F value of 65.81 which was significant at p = 0.000. The use of an integrated approach to science instruction decreases student anxiety, increases enjoyment of science and motivation in science more than a traditional approach to teaching science. The use of an integrated approach to science instruction increases student achievement on extended response assessments that measure integrated conceptual knowledge and increases student achievement on traditional summative assessments.

Assessing performance outcomes of new graduates utilizing simulation in a military transition program.

PubMed

Hughes, Robie V; Smith, Sherrill J; Sheffield, Clair M; Wier, Grady

2013-01-01

This multi-site, quasi-experimental study examined the performance outcomes of nurses (n = 152) in a military nurse transition program. A modified-performance instrument was used to assess participants in two high-fidelity simulation scenarios. Although results indicated a significant increase in scores posttraining, only moderate interrater reliability results were found for the new instrument. These findings have implications for nurse educators assessing performance-based outcomes of new nurses completing transition programs.

Co-exposure to pyridostigmine bromide, DEET, and/or permethrin causes sensorimotor deficit and alterations in brain acetylcholinesterase activity.

PubMed

Abou-Donia, Mohamed B; Dechkovskaia, Anjelika M; Goldstein, Larry B; Abdel-Rahman, Ali; Bullman, Sarah L; Khan, Wasiuddin A

2004-02-01

Military personnel deployed in the Persian Gulf War (PGW) were exposed to a combination of chemicals, including pyridostigmine bromide (PB), DEET, and permethrin. We investigated the dose-response effects of these chemicals, alone or in combination, on the sensorimotor performance and cholinergic system of male Sprague-Dawley rats. Animals were treated with a daily dermal dose of DEET and/or permethrin for 60 days and/or PB (gavage) during the last 15 days. Neurobehavioral performance was assessed on day 60 following the beginning of the treatment with DEET and permethrin. The rats were sacrificed 24 h after the last treatment for biochemical evaluations. PB alone, or in combination with DEET, or DEET and permethrin resulted in deficits in beam-walk score and longer beam-walk times compared to controls. PB alone, or in combination with DEET, permethrin, or DEET and permethrin caused impairment in incline plane performance and forepaw grip strength. PB alone at all doses slightly inhibited plasma butyrylcholinesterase activity, whereas combination of PB with DEET or permethrin increased its activity. Brainstem acetylcholinesterase (AChE) activity significantly increased following treatment with combinations of either DEET or permethrin at all doses, whereas the cerebellum showed a significant increase in AChE activity following treatment with a combination of PB/DEET/permethrin. Co-exposure to PB, DEET, and permethrin resulted in significant inhibition in AChE in midbrain. PB alone or in combination with DEET and permethrin at all doses increased ligand binding for m2 muscarinic acetylcholine receptor in the cortex. In addition, PB and DEET together or a combination of PB, DEET, and permethrin significantly increased ligand binding for nicotinic acetylcholine receptor. These results suggest that exposure to various doses of PB, alone and in combination with DEET and permethrin, leads to sensorimotor deficits and differential alterations of the cholinergic system in the CNS.

A comparison of hemisphere-specific training pattern in Inter-limb Learning Transfer (ILT) for stroke patients with hemiparesis.

PubMed

Yoo, In-gyu; Jung, Min-ye; Yoo, Eun-young; Park, Ji-hyuk; Kang, Dae-hyuk; Lee, Jin

2014-01-01

Stroke patients have major problems with impaired upper-extremity function. Unfortunately, many patients do not experience a full recovery from movement deficits in the upper extremities. The purpose of this study was to compare the effectiveness of inter-limb learning transfer (ILT) to the contralateral upper limb after both hemisphere-specific and -unspecific ipsilateral upper limb training for stroke patients with hemiparesis. Twenty-four stroke patients with hemiparesis participated. The hemisphere-specific training group performed reaching movements in a customized training setting in which non-dominant limb training participants began from a single starting location and proceeded to one of three target locations (1S3T condition); the dominant limb training participants started from one of three starting locations and proceeded to a single target location (3S1T condition). The hemisphere-unspecific training group performed these movements starting under reverse-start and target conditions. The non-dominant to dominant limb transfer, the hemisphere-specific training group performance time decreased significantly as compared with the pre-training session (p < 0.05). Also, the isolation contraction ratio was decreased significantly from that of the pre-training session in the biceps brachii muscles and increased significantly in the upper trapezius muscles (p < 0.05). And, dominant to non-dominant limb transfer in the hemisphere-specific training group significantly increased RMS amplitudes from the pre-training session in the biceps brachii and triceps muscles (p < 0.05). Also, the isolation contraction ratio was increased significantly from that of the pre-training session in the biceps brachii muscles and decreased significantly in the upper trapezius muscles (p < 0.05). However, the hemisphere-unspecific training group showed no significant differences in inter-limb learning transfer (ILT). The transfer of hemisphere-specific training from one arm to the other had a more positive influence on functional recovery than did hemisphere-unspecific training for patients with stroke and hemiparesis.

Geometric effects in applied-field MPD thrusters

NASA Technical Reports Server (NTRS)

Myers, R. M.; Mantenieks, M.; Sovey, J.

1990-01-01

Three applied-field magnetoplasmadynamic (MPD) thruster geometries were tested with argon propellant to establish the influence of electrode geometry on thruster performance. The thrust increased approximately linearly with anode radius, while the discharge and electrode fall voltages increased quadratically with anode radius. All these parameters increased linearly with applied-field strength. Thrust efficiency, on the other hand, was not significantly influenced by changes in geometry over the operating range studied, though both thrust and thermal efficiencies increased monotonically with applied field strength. The best performance, 1820 sec I (sub sp) at 20 percent efficiency, was obtained with the largest radius anode at the highest discharge current (1500 amps) and applied field strength (0.4 Tesla).

Geometric effects in applied-field MPD thrusters

NASA Technical Reports Server (NTRS)

Myers, R. M.; Mantenieks, M.; Sovey, James S.

1990-01-01

Three applied-field magnetoplasmadynamic (MPD) thruster geometries were tested with argon propellant to establish the influence of electrode geometry on thruster performance. The thrust increased approximately linearly with anode radius, while the discharge and electrode fall voltages increased quadratically with anode radius. All these parameters increased linearly with applied-field strength. Thrust efficiency, on the other hand, was not significantly influenced by changes in geometry over the operating range studied, though both thrust and thermal efficiencies increased monotonically with applied field strength. The best performance, 1820 sec I(sub sp) at 20 percent efficiency, was obtained with the largest radius anode at the highest discharge current (1500 amps) and applied field strength (0.4 Tesla).

Effect of various kinds of beverages on stress oxidative, F2 isoprostane, serum lipid and blood glucose of elite taekwondo players.

PubMed

Maghsoudi, Zahra; Shiranian, Ashfin; Askai, Gholamreza; Ghaisvand, Reza

2016-01-01

Athletes' recovery is important in improving their performance. Nutritional strategies can be effective in enhancing recovery rate. Choosing the best food items in appropriate intervals can play effective roles in resynthesis of fuels and recovery of muscle injury. Beverage micro and macronutrient content are helpful in fuel restoration. In this study, we assess the effects of various kinds of beverages on oxidative stress, muscle injury, and metabolic risk factors in taekwondo players. This quasi-experimental study was performed on 21 taekwondo players of Isfahan. After collecting fasting blood, they performed runningbased anaerobic sprint test (RAST). Blood lactate was tested again and participants were divided into 3 intervention groups, that is, receiving 500 cc dough, non-alcoholic beer, and chocolate milk at 4 day intervals. After a 2-h recovery period, blood sampling was repeated. Elites consumed other beverages in later phases. Dietary intake and fasting triglyceride, cholesterol, blood sugar, lactate dehydrogenase, and F 2 -isoprostane concentrations were determined. Data were analyzed with a simple repeated-measures test and post-hoc tests using the Statistical Package for the Social Sciences software. Data showed that cholesterol levels non-significantly decreased after intervention. Triglyceride level was lower after taking dough and carbohydrate replacement drink. Blood glucose concentration increased after intervention periods, however, this increase was significant only after non-alcoholic beverage consumption. Lactate dehydrogenase levels reduced after all cycles, however, F 2 -isoprostane level showed no significant change. There was not significant change in lactate dehydrogenase and F 2 -isoprostane levels. Non-alcoholic beer consumption can reduce lactate dehydrogenase concentration; however, it leads to blood sugar increase. Moreover, dough consumption significantly reduced triglyceride level in taekwondo players.

Design, simulation and comparative analysis of CNT based cascode operational transconductance amplifiers

NASA Astrophysics Data System (ADS)

Nizamuddin, M.; Loan, Sajad A.; Alamoud, Abdul R.; Abbassi, Shuja A.

2015-10-01

In this work, design and calibrated simulation of carbon nanotube field effect transistor (CNTFET)-based cascode operational transconductance amplifiers (COTA) have been performed. Three structures of CNTFET-based COTAs have been designed using HSPICE and have been compared with the conventional CMOS-based COTAs. The proposed COTAs include one using pure CNTFETs and two others that employ CNTFETs, as well as the conventional MOSFETs. The simulation study has revealed that the CNTFET-based COTAs have significantly outperformed the conventional MOSFET-based COTAs. A significant increase in dc gain, output resistance and slew rate of 81.4%, 25% and 13.2%, respectively, have been achieved in the proposed pure CNT-based COTA in comparison to the conventional CMOS-based COTA. The power consumption in the pure CNT-COTA is 324 times less in comparison to the conventional CMOS-COTA. Further, the phase margin (PM), gain margin (GM), common mode and power supply rejection ratios have been significantly increased in the proposed CNT-based COTAs in comparison to the conventional CMOS-based COTAs. Furthermore, to see the advantage of cascoding, the proposed CNT-based cascode OTAs have been compared with the CNT-based OTAs. It has been observed that by incorporating the concept of cascode in the CNTFET-based OTAs, significant increases in gain (12.5%) and output resistance (13.07%) have been achieved. The performance of the proposed COTAs has been further observed by changing the number of CNTs (N), CNT pitch (S) and CNT diameter (DCNT) in the CNTFETs used. It has been observed that the performance of the proposed COTAs can be significantly improved by using optimum values of N, S and DCNT.

The acute effects of grape polyphenols supplementation on endothelial function in adults: meta-analyses of controlled trials.

PubMed

Li, Shao-Hua; Tian, Hong-Bo; Zhao, Hong-Jin; Chen, Liang-Hua; Cui, Lian-Qun

2013-01-01

The acute effects of grape polyphenols on endothelial function in adults are inconsistent. Here, we performed meta-analyses to determine these acute effects as measured by flow-mediated dilation (FMD). Trials were searched in PubMed, Embase and the Cochrane Library database. Summary estimates of weighted mean differences (WMDs) and 95% CIs were obtained by using random-effects models. Meta-regression and subgroup analyses were performed to identify the source of heterogeneity. The protocol details of our meta-analysis have been submitted to the PROSPERO register and our registration number is CRD42013004157. Nine studies were included in the present meta-analyses. The results showed that the FMD level was significantly increased in the initial 120 min after intake of grape polyphenols as compared with controls. Meta-regression and subgroup analyses were performed and showed that a health status was the main effect modifier of the significant heterogeneity. Subgroups indicated that intake of grape polyphenols could significantly increase FMD in healthy subjects, and the increased FMD appeared to be more obviously in subjects with high cardiovascular risk factors. Moreover, the peak effect of grape polyphenols on FMD in healthy subjects was found 30 min after ingestion, which was different from the effect in subjects with high cardiovascular risk factors, in whom the peak effect was found 60 min after ingestion. Endothelial function can be significantly improved in healthy adults in the initial 2 h after intake of grape polyphenols. The acute effect of grape polyphenols on endothelial function may be more significant but the peak effect is delayed in subjects with a smoking history or coronary heart disease as compared with the healthy subjects.

The Acute Effects of Grape Polyphenols Supplementation on Endothelial Function in Adults: Meta-Analyses of Controlled Trials

PubMed Central

Li, Shao-Hua; Tian, Hong-Bo; Zhao, Hong-Jin; Chen, Liang-Hua; Cui, Lian-Qun

2013-01-01

Background The acute effects of grape polyphenols on endothelial function in adults are inconsistent. Here, we performed meta-analyses to determine these acute effects as measured by flow-mediated dilation (FMD). Methods Trials were searched in PubMed, Embase and the Cochrane Library database. Summary estimates of weighted mean differences (WMDs) and 95% CIs were obtained by using random-effects models. Meta-regression and subgroup analyses were performed to identify the source of heterogeneity. The protocol details of our meta-analysis have been submitted to the PROSPERO register and our registration number is CRD42013004157. Results Nine studies were included in the present meta-analyses. The results showed that the FMD level was significantly increased in the initial 120 min after intake of grape polyphenols as compared with controls. Meta-regression and subgroup analyses were performed and showed that a health status was the main effect modifier of the significant heterogeneity. Subgroups indicated that intake of grape polyphenols could significantly increase FMD in healthy subjects, and the increased FMD appeared to be more obviously in subjects with high cardiovascular risk factors. Moreover, the peak effect of grape polyphenols on FMD in healthy subjects was found 30 min after ingestion, which was different from the effect in subjects with high cardiovascular risk factors, in whom the peak effect was found 60 min after ingestion. Conclusions Endothelial function can be significantly improved in healthy adults in the initial 2 h after intake of grape polyphenols. The acute effect of grape polyphenols on endothelial function may be more significant but the peak effect is delayed in subjects with a smoking history or coronary heart disease as compared with the healthy subjects. PMID:23894543

Joint pathology and behavioral performance in autoimmune MRL-lpr Mice.

PubMed

Sakić, B; Szechtman, H; Stead, R H; Denburg, J A

1996-09-01

Young autoimmune MRL-lpr mice perform more poorly than age-matched controls in tests of exploration, spatial learning, and emotional reactivity. Impaired behavioral performance coincides temporally with hyperproduction of autoantibodies, infiltration of lymphoid cells into the brain, and mild arthritic-like changes in hind paws. Although CNS mechanisms have been suggested to mediate behavioral deficits, it was not clear whether mild joint pathology significantly affected behavioral performance. Previously we observed that 11-week-old MRL-lpr mice showed a trend for disturbed performance when crossing a narrow beam. The first aim of the present study was to test the significance of this trend by increasing the sample size and, second, to examine the possibility that arthritis-like changes interfere with performance in brief locomotor tasks. For the purpose of the second goal, 18-week-old mice that differ widely in severity of joint disease were selectively taken from the population and tested in beam walking and swimming tasks. It was expected that the severity of joint inflammation would be positively correlated with the degree of locomotor impairment. The larger sample size revealed that young MRL-lpr mice perform significantly more poorly than controls on the beam-walking test, as evidenced by more foot slips and longer traversing time. However, significant correlation between joint pathology scores and measures of locomotion could not be detected. The lack of such relationship suggests that mild joint pathology does not significantly contribute to impaired performance in young, autoimmune MRL-lpr mice tested in short behavioral tasks.

Quantifying the impact of cross coverage on physician's workload and performance in radiation oncology.

PubMed

Mosaly, Prithima R; Mazur, Lukasz M; Jones, Ellen L; Hoyle, Lesley; Zagar, Timothy; Chera, Bhishamjit S; Marks, Lawrence B

2013-01-01

To quantitatively assess the difference in workload and performance of radiation oncology physicians during radiation therapy treatment planning tasks under the conditions of "cross coverage" versus planning a patient with whom they were familiar. Eight physicians (3 experienced faculty physicians and 5 physician residents) performed 2 cases. The first case represented a "cross-coverage" scenario where the physicians had no prior information about the case to be planned. The second exposure represented a "regular-coverage" scenario where the physicians were familiar with the patient case to be planned. Each case involved 3 tasks to be completed systematically. Workload was assessed both subjectively (perceived) using National Aeronautics and Space Administration-Task Load Index (NASA-TLX), and objectively (physiological) throughout the task using eye data (via monitoring pupil size and blink rate). Performance of each task and the case was measured using completion time. Subjective willingness to approve or disapprove the generated plan was obtained after completion of the case only. Forty-eight perceived and 48 physiological workload assessments were obtained. Overall, results revealed a significant increase in perceived workload (high NASA-TLX score) and decrease in performance (longer completion time and reduced approval rate) during cross coverage. There were nonsignificant increases in pupil diameter and decreases in the blink rate during cross-coverage versus regular-coverage scenario. In both cross-coverage and regular-coverage scenarios the level of experience did not affect workload and performance. The cross-coverage scenario significantly increases perceived workload and degrades performance versus regular coverage. Hence, to improve patient safety, efforts must be made to develop policies, standard operating procedures, and usability improvements to electronic medical record and treatment planning systems for "easier" information processing to deal with cross coverage, while recognizing strengths and limitations of human performance. Published by Elsevier Inc.

Effects of resveratrol on memory performance, hippocampal functional connectivity, and glucose metabolism in healthy older adults.

PubMed

Witte, A Veronica; Kerti, Lucia; Margulies, Daniel S; Flöel, Agnes

2014-06-04

Dietary habits such as caloric restriction or nutrients that mimic these effects may exert beneficial effects on brain aging. The plant-derived polyphenol resveratrol has been shown to increase memory performance in primates; however, interventional studies in older humans are lacking. Here, we tested whether supplementation of resveratrol would enhance memory performance in older adults and addressed potential mechanisms underlying this effect. Twenty-three healthy overweight older individuals that successfully completed 26 weeks of resveratrol intake (200 mg/d) were pairwise matched to 23 participants that received placebo (total n = 46, 18 females, 50-75 years). Before and after the intervention/control period, subjects underwent memory tasks and neuroimaging to assess volume, microstructure, and functional connectivity (FC) of the hippocampus, a key region implicated in memory functions. In addition, anthropometry, glucose and lipid metabolism, inflammation, neurotrophic factors, and vascular parameters were assayed. We observed a significant effect of resveratrol on retention of words over 30 min compared with placebo (p = 0.038). In addition, resveratrol led to significant increases in hippocampal FC, decreases in glycated hemoglobin (HbA1c) and body fat, and increases in leptin compared with placebo (all p < 0.05). Increases in FC between the left posterior hippocampus and the medial prefrontal cortex correlated with increases in retention scores and with decreases in HbA1c (all p < 0.05). This study provides initial evidence that supplementary resveratrol improves memory performance in association with improved glucose metabolism and increased hippocampal FC in older adults. Our findings offer the basis for novel strategies to maintain brain health during aging. Copyright © 2014 the authors 0270-6474/14/347862-09$15.00/0.

Impact of Frequent Interruption on Nurses' Patient-Controlled Analgesia Programming Performance.

PubMed

Campoe, Kristi R; Giuliano, Karen K

2017-12-01

The purpose was to add to the body of knowledge regarding the impact of interruption on acute care nurses' cognitive workload, total task completion times, nurse frustration, and medication administration error while programming a patient-controlled analgesia (PCA) pump. Data support that the severity of medication administration error increases with the number of interruptions, which is especially critical during the administration of high-risk medications. Bar code technology, interruption-free zones, and medication safety vests have been shown to decrease administration-related errors. However, there are few published data regarding the impact of number of interruptions on nurses' clinical performance during PCA programming. Nine acute care nurses completed three PCA pump programming tasks in a simulation laboratory. Programming tasks were completed under three conditions where the number of interruptions varied between two, four, and six. Outcome measures included cognitive workload (six NASA Task Load Index [NASA-TLX] subscales), total task completion time (seconds), nurse frustration (NASA-TLX Subscale 6), and PCA medication administration error (incorrect final programming). Increases in the number of interruptions were associated with significant increases in total task completion time ( p = .003). We also found increases in nurses' cognitive workload, nurse frustration, and PCA pump programming errors, but these increases were not statistically significant. Complex technology use permeates the acute care nursing practice environment. These results add new knowledge on nurses' clinical performance during PCA pump programming and high-risk medication administration.

Predicting the 'where' and resolving the 'what' of a moving target: a dichotomy of abilities.

PubMed

Long, G M; Vogel, C A

1998-01-01

Anticipation timing (AT) and dynamic visual acuity (DVA) were assessed in a group of college students (n = 60) under a range of velocity and duration conditions. Subjects participated in two identical sessions 1 week apart. Consistently with previous work, DVA performance worsened as velocity increased and as target duration decreased; and there was a significant improvement from the first to the second session. In contrast, AT performance improved as velocity increased, whereas no improvement from the first to the second session was indicated; but increasing duration again benefited performance. Correlational analyses comparing DVA and AT did not reveal any systematic relationship between the two visual tasks. A follow-up study with different instructions on the AT task revealed the same pattern of AT performance, suggesting the generalizability of the obtained stimulus relationships for the AT task. The importance of the often-overlooked role of stimulus variables on the AT task is discussed.

Effect of Curcumin Supplementation on Physiological Fatigue and Physical Performance in Mice

PubMed Central

Huang, Wen-Ching; Chiu, Wan-Chun; Chuang, Hsiao-Li; Tang, Deh-Wei; Lee, Zon-Min; Wei, Li; Chen, Fu-An; Huang, Chi-Chang

2015-01-01

Curcumin (CCM) is a well-known phytocompound and food component found in the spice turmeric and has multifunctional bioactivities. However, few studies have examined its effects on exercise performance and physical fatigue. We aimed to evaluate the potential beneficial effects of CCM supplementation on fatigue and ergogenic function following physical challenge in mice. Male ICR mice were divided into four groups to receive vehicle or CCM (180 μg/mL) by oral gavage at 0, 12.3, 24.6, or 61.5 mL/kg/day for four weeks. Exercise performance and anti-fatigue function were evaluated after physical challenge by forelimb grip strength, exhaustive swimming time, and levels of physical fatigue-associated biomarkers serum lactate, ammonia, blood urea nitrogen (BUN), and glucose and tissue damage markers such as aspartate transaminase (AST), alanine transaminase (ALT), and creatine kinase (CK). CCM supplementation dose-dependently increased grip strength and endurance performance and significantly decreased lactate, ammonia, BUN, AST, ALT, and CK levels after physical challenge. Muscular glycogen content, an important energy source for exercise, was significantly increased. CCM supplementation had few subchronic toxic effects. CCM supplementation may have a wide spectrum of bioactivities for promoting health, improving exercise performance and preventing fatigue. PMID:25647661

Subsonic flight test evaluation of a performance seeking control algorithm on an F-15 airplane

NASA Technical Reports Server (NTRS)

Gilyard, Glenn B.; Orme, John S.

1992-01-01

The subsonic flight test evaluation phase of the NASA F-15 (powered by F 100 engines) performance seeking control program was completed for single-engine operation at part- and military-power settings. The subsonic performance seeking control algorithm optimizes the quasi-steady-state performance of the propulsion system for three modes of operation. The minimum fuel flow mode minimizes fuel consumption. The minimum thrust mode maximizes thrust at military power. Decreases in thrust-specific fuel consumption of 1 to 2 percent were measured in the minimum fuel flow mode; these fuel savings are significant, especially for supersonic cruise aircraft. Decreases of up to approximately 100 degree R in fan turbine inlet temperature were measured in the minimum temperature mode. Temperature reductions of this magnitude would more than double turbine life if inlet temperature was the only life factor. Measured thrust increases of up to approximately 15 percent in the maximum thrust mode cause substantial increases in aircraft acceleration. The system dynamics of the closed-loop algorithm operation were good. The subsonic flight phase has validated the performance seeking control technology, which can significantly benefit the next generation of fighter and transport aircraft.

In Vivo Physiological Experiments in the Random Positioning Macine: A Study on the Rat Intestinal Transit

NASA Astrophysics Data System (ADS)

Peana, A. T.; Marzocco, S.; Bianco, G.; Autore, G.; Pinto, A.; Pippia, P.

2008-06-01

The aim of this work is to evaluate the rat intestinal transit as well as the expression of enzymes involved in this process and in gastrointestinal homeostasis as ciclooxygenase (COX-1 and COX-2), the inducibile isoform of nitric oxide synthase (iNOS), ICAM-1 and heat shock proteins HSP70 and HSP90. The modeled microgravity conditions were performed utilizing a three-dimensional clinostat, the Random Positioning Machine (RPM). Our results indicate that modeled microgravity significantly reduce rat intestinal transit. Western blot analysis on small intestine tissues of RPM rats reveals a significant increase in iNOS expression, a significant reduction in COX-2 levels, while COX-1 expression remains unaltered, and a significant increase in ICAM-1 and HSP 70 expression. Also a significant increase in HSP 90 stomach expression indicates a strong effect of simulated low g on gastrointestinal homeostasis.

The Impact of Performance Ratings on Job Satisfaction for Public School Teachers

ERIC Educational Resources Information Center

Koedel, Cory; Li, Jiaxi; Springer, Matthew G.; Tan, Li

2017-01-01

Spurred by the federal Race to the Top competition, the state of Tennessee implemented a comprehensive statewide educator evaluation system in 2011. The new system is designed to increase the rigor of evaluations and better differentiate teachers based on performance. The use of more differentiated ratings represents a significant shift in…

Relationship between Running Speed and Cognitive Processes in Orienteering: Two Empirical Studies.

ERIC Educational Resources Information Center

Cheshikhina, Valentina V.

1993-01-01

Fourteen qualified orienteers completed a stepwise increased treadmill velocity test in which controls had to be transferred from a master map. Orienteering accuracy was greatest at the anaerobic threshold speed. In a second study, 17 orienteers performed arithmetic tasks before and after a treadmill workout. Performance was significantly better…

Depressed left ventricular performance. Response to volume infusion in patients with sepsis and septic shock

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ognibene, F.P.; Parker, M.M.; Natanson, C.

Volume infusion, to increase preload and to enhance ventricular performance, is accepted as initial management of septic shock. Recent evidence has demonstrated depressed myocardial function in human septic shock. We analyzed left ventricular performance during volume infusion using serial data from simultaneously obtained pulmonary artery catheter hemodynamic measurements and radionuclide cineangiography. Critically ill control subjects (n = 14), patients with sepsis but without shock (n = 21), and patients with septic shock (n = 21) had prevolume infusion hemodynamic measurements determined and received statistically similar volumes of fluid resulting in similar increases in pulmonary capillary wedge pressure. There was amore » strong trend (p = 0.004) toward less of a change in left ventricular stroke work index (LVSWI) after volume infusion in patients with sepsis and septic shock compared with control subjects. The LVSWI response after volume infusion was significantly less in patients with septic shock when compared with critically ill control subjects (p less than 0.05). These data demonstrate significantly altered ventricular performance, as measured by LVSWI, in response to volume infusion in patients with septic shock.« less

Health Risk Assessment of Women in Submarines: Reproductive and Developmental Toxicity Evaluation of Major Submarine Atmosphere Components (CO, CO2 and O2) in Rats (Rattus norvegicus) - Phase II (Neurological and Reproductive Performance Study)

DTIC Science & Technology

2011-10-11

exposed parents. Statistically significant increases in hematopoietic activity (mild polycythemia , leukocytosis and thrombocytosis) were...Tables 25 & 26). Polycythemia (increased red blood cells, with expected increases in hemoglobin and hematocrit) is an established effect of

Effect of public symphysiodesis on pelvic development in the skeletally immature greyhound.

PubMed

Swainson, S W; Conzemius, M G; Riedesel, E A; Smith, G K; Riley, C B

2000-01-01

To evaluate the effect of pubic symphysiodesis (PS) on pelvic development in skeletally immature dogs. Prospective randomized clinical trial. Eight 4 month-old, sexually intact female Greyhounds. Initial PS was performed at 4 months of age using a powered stapling device. Because of failure of the initial surgery, a second PS was performed 1 month later by resecting the pubic symphysis with a rongeur followed by placement of handmade bone staples in four dogs. Sham PS was performed in four control dogs at 4 months of age. Pubic growth rate and pelvic development were evaluated using standard plane radiography and computed tomography. Specific measurements included acetabular ventroversion, Norberg angle, lateral center-edge angle, and pelvic inlet dimensions. Hip distraction indices were determined as well. PS at 4 months of age using a stapling device failed. Pubic symphysiodesis using hand made staples was successful at 5 months of age and did not result in any clinically significant intraoperative or postoperative complications. Pubic symphysiodesis markedly decreased pubic symphysis growth in the treatment group. Hip distraction indices and pelvic inlet circumference, area, and width significantly decreased in treated dogs compared to those in the control group. Acetabular ventroversion was significantly increased in treated dogs compared to those in the control group. PS decreases pelvic canal size, increases acetabular ventroversion, and does not appear to have any clinically significant complications. PS performed in skeletally immature dogs with hip dysplasia may provide an effect similar to a triple pelvic osteotomy and warrants further investigation.

What happens to your brain on the way to Mars.

PubMed

Parihar, Vipan K; Allen, Barrett; Tran, Katherine K; Macaraeg, Trisha G; Chu, Esther M; Kwok, Stephanie F; Chmielewski, Nicole N; Craver, Brianna M; Baulch, Janet E; Acharya, Munjal M; Cucinotta, Francis A; Limoli, Charles L

2015-05-01

As NASA prepares for the first manned spaceflight to Mars, questions have surfaced concerning the potential for increased risks associated with exposure to the spectrum of highly energetic nuclei that comprise galactic cosmic rays. Animal models have revealed an unexpected sensitivity of mature neurons in the brain to charged particles found in space. Astronaut autonomy during long-term space travel is particularly critical as is the need to properly manage planned and unanticipated events, activities that could be compromised by accumulating particle traversals through the brain. Using mice subjected to space-relevant fluences of charged particles, we show significant cortical- and hippocampal-based performance decrements 6 weeks after acute exposure. Animals manifesting cognitive decrements exhibited marked and persistent radiation-induced reductions in dendritic complexity and spine density along medial prefrontal cortical neurons known to mediate neurotransmission specifically interrogated by our behavioral tasks. Significant increases in postsynaptic density protein 95 (PSD-95) revealed major radiation-induced alterations in synaptic integrity. Impaired behavioral performance of individual animals correlated significantly with reduced spine density and trended with increased synaptic puncta, thereby providing quantitative measures of risk for developing cognitive decrements. Our data indicate an unexpected and unique susceptibility of the central nervous system to space radiation exposure, and argue that the underlying radiation sensitivity of delicate neuronal structure may well predispose astronauts to unintended mission-critical performance decrements and/or longer-term neurocognitive sequelae.

Effects of equal-volume resistance training with different training frequencies in muscle size and strength in trained men

PubMed Central

Fisher, James; Steele, James; Campos, Mario H.; Silva, Marcelo H.; Paoli, Antonio; Giessing, Jurgen; Bottaro, Martim

2018-01-01

Background The objective of the present study was to compare the effects of equal-volume resistance training (RT) performed with different training frequencies on muscle size and strength in trained young men. Methods Sixteen men with at least one year of RT experience were divided into two groups, G1 and G2, that trained each muscle group once and twice a week, respectively, for 10 weeks. Elbow flexor muscle thickness (MT) was measured using a B-Mode ultrasound and concentric peak torque of elbow extensors and flexors were assessed by an isokinetic dynamometer. Results ANOVA did not reveal group by time interactions for any variable, indicating no difference between groups for the changes in MT or PT of elbow flexors and extensors. Notwithstanding, MT of elbow flexors increased significantly (3.1%, P < 0.05) only in G1. PT of elbow flexors and extensors did not increase significantly for any group. Discussion The present study suggest that there were no differences in the results promoted by equal-volume resistance training performed once or twice a week on upper body muscle strength in trained men. Only the group performing one session per week significantly increased the MT of their elbow flexors. However, with either once or twice a week training, adaptations appear largely minimal in previously trained males.

Effects of equal-volume resistance training with different training frequencies in muscle size and strength in trained men.

PubMed

Gentil, Paulo; Fisher, James; Steele, James; Campos, Mario H; Silva, Marcelo H; Paoli, Antonio; Giessing, Jurgen; Bottaro, Martim

2018-01-01

The objective of the present study was to compare the effects of equal-volume resistance training (RT) performed with different training frequencies on muscle size and strength in trained young men. Sixteen men with at least one year of RT experience were divided into two groups, G1 and G2, that trained each muscle group once and twice a week, respectively, for 10 weeks. Elbow flexor muscle thickness (MT) was measured using a B-Mode ultrasound and concentric peak torque of elbow extensors and flexors were assessed by an isokinetic dynamometer. ANOVA did not reveal group by time interactions for any variable, indicating no difference between groups for the changes in MT or PT of elbow flexors and extensors. Notwithstanding, MT of elbow flexors increased significantly (3.1%, P  < 0.05) only in G1. PT of elbow flexors and extensors did not increase significantly for any group. The present study suggest that there were no differences in the results promoted by equal-volume resistance training performed once or twice a week on upper body muscle strength in trained men. Only the group performing one session per week significantly increased the MT of their elbow flexors. However, with either once or twice a week training, adaptations appear largely minimal in previously trained males.

Effects of smoking marijuana on brain perfusion and cognition.

PubMed

O'Leary, Daniel S; Block, Robert I; Koeppel, Julie A; Flaum, Michael; Schultz, Susan K; Andreasen, Nancy C; Ponto, Laura Boles; Watkins, G Leonard; Hurtig, Richard R; Hichwa, Richard D

2002-06-01

The effects of smoking marijuana on regional cerebral blood flow (rCBF) and cognitive performance were assessed in 12 recreational users in a double-blinded, placebo-controlled study. PET with [(15)Oxygen]-labeled water ([(15)O]H(2)O) was used to measure rCBF before and after smoking of marijuana and placebo cigarettes, as subjects repeatedly performed an auditory attention task. Smoking marijuana resulted in intoxication, as assessed by a behavioral rating scale, but did not significantly alter mean behavioral performance on the attention task. Heart rate and blood pressure increased dramatically following smoking of marijuana but not placebo cigarettes. However, mean global CBF did not change significantly. Increased rCBF was observed in orbital and mesial frontal lobes, insula, temporal poles, anterior cingulate, as well as in the cerebellum. The increases in rCBF in anterior brain regions were predominantly in "paralimbic" regions and may be related to marijuana's mood-related effects. Reduced rCBF was observed in temporal lobe auditory regions, in visual cortex, and in brain regions that may be part of an attentional network (parietal lobe, frontal lobe and thalamus). These rCBF decreases may be the neural basis of perceptual and cognitive alterations that occur with acute marijuana intoxication. There was no significant rCBF change in the nucleus accumbens or other reward-related brain regions, nor in basal ganglia or hippocampus, which have a high density of cannabinoid receptors.

Reducing Communication in Algebraic Multigrid Using Additive Variants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vassilevski, Panayot S.; Yang, Ulrike Meier

Algebraic multigrid (AMG) has proven to be an effective scalable solver on many high performance computers. However, its increasing communication complexity on coarser levels has shown to seriously impact its performance on computers with high communication cost. Moreover, additive AMG variants provide not only increased parallelism as well as decreased numbers of messages per cycle but also generally exhibit slower convergence. Here we present various new additive variants with convergence rates that are significantly improved compared to the classical additive algebraic multigrid method and investigate their potential for decreased communication, and improved communication-computation overlap, features that are essential for goodmore » performance on future exascale architectures.« less

Reducing Communication in Algebraic Multigrid Using Additive Variants

DOE PAGES

Vassilevski, Panayot S.; Yang, Ulrike Meier

2014-02-12

Algebraic multigrid (AMG) has proven to be an effective scalable solver on many high performance computers. However, its increasing communication complexity on coarser levels has shown to seriously impact its performance on computers with high communication cost. Moreover, additive AMG variants provide not only increased parallelism as well as decreased numbers of messages per cycle but also generally exhibit slower convergence. Here we present various new additive variants with convergence rates that are significantly improved compared to the classical additive algebraic multigrid method and investigate their potential for decreased communication, and improved communication-computation overlap, features that are essential for goodmore » performance on future exascale architectures.« less

Antipsychotic-Induced Changes in Blood Levels of Leptin in Schizophrenia: A Meta-Analysis

PubMed Central

Potvin, Stéphane; Zhornitsky, Simon; Stip, Emmanuel

2015-01-01

Objectives: Weight gain is a major side effect of antipsychotics (APs), which contributes to poor treatment adherence and significant morbidity. The mechanisms involved in AP-induced weight gain are incompletely understood. Recently, it has been proposed that changes in leptin, an cadipocyte-derived hormone exerting anorexigenic effects, may be involved in AP-induced weight gain. Thus far, studies on leptin changes during AP treatment have produced inconsistent results, prompting our group to perform a meta-analysis. Method: A search of the literature was performed using PubMed and Embase. Studies were included only if reporting peripheral levels of leptin before and after AP treatment in schizophrenia. Effect size estimates were calculated with Hedges g and were aggregated using a random effects model as results were heterogeneous (P < 0.10). Meta-regression analyses were performed using study length and changes in body mass index (BMI) as moderator variables. Results: Twenty-eight studies were retrieved, including 39 comparisons. A moderate and positive effect size was observed across studies. Olanzapine, clozapine, and quetiapine produced moderate leptin elevations, whereas haloperidol and risperidone were associated with small (nonsignificant) leptin changes. Across studies, BMI changes were significantly associated with increases in leptin levels. There was no effect of sex on AP-induced changes in leptin. Conclusions: A physiological role of leptin in AP-induced weight gain is supported because the most significant leptin increases were observed with APs inducing the most weight gain and because of the observed association between leptin increases and BMI changes. The overall increase in leptin levels suggests that leptin acts as a negative feedback signal in the event of fat increase. PMID:25886677

Changbai Mountain Ginseng (Panax ginseng C.A. Mey) Extract Supplementation Improves Exercise Performance and Energy Utilization and Decreases Fatigue-Associated Parameters in Mice.

PubMed

Ma, Guo-Dong; Chiu, Chun-Hui; Hsu, Yi-Ju; Hou, Chien-Wen; Chen, Yi-Ming; Huang, Chi-Chang

2017-02-05

Changbai Mountain Ginseng (CMG, Panax ginseng C.A. Mey) is a traditional medicine commonly found in Northeast China and grows at elevations of 2000 m or higher in the Changbai Mountain Range. CMG, considered to be a "buried treasure medicine", is priced higher than other types of ginseng. However, few studies have demonstrated the effects of CMG supplementation on exercise performance, physical fatigue, and the biochemical profile. The major compound of CMG extract was characterized by electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS). Male ICR mice were divided into 3 groups, the vehicle, CMG-1X and CMG-5X groups ( n = 8 per group), and respectively administered 0, 5, or 25 mg/kg/day of CMG extract orally for four weeks. HPLC-ESI-MS/MS results showed that the major compound in CMG extract is ginsenoside Ro. CMG extract significantly increased muscle weight and relative muscle weight (%). CMG extract supplementation dose-dependently increased grip strength ( p < 0.0001) and endurance swimming time, decreased levels of serum lactate ( p < 0.0001), ammonia ( p < 0.0001), creatine kinase (CK, p = 0.0002), and blood urea nitrogen ( p < 0.0001), and economized glucose levels ( p < 0.0001) after acute exercise challenge. The glycogen in the gastrocnemius muscle was significantly increased with CMG extract treatment. Biochemical profile results showed that creatinine and triacylglycerol significantly decreased and total protein and glucose increased with CMG treatment. This is the first report that CMG extract supplementation increases muscle mass, improves exercise performance and energy utilization, and decreases fatigue-associated parameters in vivo. The major component of CMG extract is ginsenoside Ro, which could be a potential bioactive compound for use as an ergogenic aid ingredient by the food industry.

Effects of dietary supplementation of organic acids and phytase on performance and intestinal histomorphology of broilers.

PubMed

Mohammadagheri, Nasibeh; Najafi, Ramin; Najafi, Gholamreza

2016-01-01

The present experiment was conducted to evaluate the effects of organic acids and phytase enzyme supplementation on performance and intestinal histomorphology of broilers. The experiment was done in a factorial arrangement 2 × 2 × 2 based on completely randomized design with eight treatments, five replicates with 12 chicks in each until 42 days of age. Diets included natural vinegar (0 and 2%), citric acid (CA; 0.00 and 1.00%) and phytase enzyme (PHY; 0.00 and 500 FTU phytase per kg of feed). One bird from each treatment replicate was randomly selected and slaughtered to evaluate the small intestinal morphology on 42 days of age. Analysis of results showed that vinegar increased feed consumption and body weight gain in total experimental period ( p ˂ 0.05), while CA significantly decreased feed consumption on 0-14 days of age ( p ˂ 0.05). No effect was observed on performance in interaction of organic acids together and with PHY group ( p > 0.05). In duodenum CA increased the villus height and width ( p ˂ 0.05) and PHY enzyme increased villus width ( p ˂ 0.05) and decreased crypt depth ( p ˂ 0.05). On the other hand, CA along with PHY significantly decreased crypt depth ( p ˂ 0.05). In jejunum PHY alone and in combination with vinegar increased the goblet cells numbers ( p ˂ 0.05), whereas vinegar significantly increased the goblet cells numbers in ileum ( p ˂ 0.05). The muscular thickness in duodenum, jejunum, and ileum was not affected among different treatment groups. The results showed that supplementation of organic acids and phytase together in this experiment, with no negative effects on each other, improved their effects on some parameters.

Understanding protocol performance: impact of test performance.

PubMed

Turner, Robert G

2013-01-01

This is the second of two articles that examine the factors that determine protocol performance. The objective of these articles is to provide a general understanding of protocol performance that can be used to estimate performance, establish limits on performance, decide if a protocol is justified, and ultimately select a protocol. The first article was concerned with protocol criterion and test correlation. It demonstrated the advantages and disadvantages of different criterion when all tests had the same performance. It also examined the impact of increasing test correlation on protocol performance and the characteristics of the different criteria. To examine the impact on protocol performance when individual tests in a protocol have different performance. This is evaluated for different criteria and test correlations. The results of the two articles are combined and summarized. A mathematical model is used to calculate protocol performance for different protocol criteria and test correlations when there are small to large variations in the performance of individual tests in the protocol. The performance of the individual tests that make up a protocol has a significant impact on the performance of the protocol. As expected, the better the performance of the individual tests, the better the performance of the protocol. Many of the characteristics of the different criteria are relatively independent of the variation in the performance of the individual tests. However, increasing test variation degrades some criteria advantages and causes a new disadvantage to appear. This negative impact increases as test variation increases and as more tests are added to the protocol. Best protocol performance is obtained when individual tests are uncorrelated and have the same performance. In general, the greater the variation in the performance of tests in the protocol, the more detrimental this variation is to protocol performance. Since this negative impact is increased as more tests are added to the protocol, greater test variation indicates using fewer tests in the protocol. American Academy of Audiology.

A genetic predisposition score for muscular endophenotypes predicts the increase in aerobic power after training: the CAREGENE study.

PubMed

Thomaes, Tom; Thomis, Martine; Onkelinx, Steven; Fagard, Robert; Matthijs, Gert; Buys, Roselien; Schepers, Dirk; Cornelissen, Véronique; Vanhees, Luc

2011-10-03

It is widely accepted that genetic variability might explain a large part of the observed heterogeneity in aerobic capacity and its response to training. Significant associations between polymorphisms of different genes with muscular strength, anaerobic phenotypes and body composition have been reported. Muscular endophenotypes are positively correlated with aerobic capacity, therefore, we tested the association of polymorphisms in twelve muscular related genes on aerobic capacity and its response to endurance training. 935 Coronary artery disease patients (CAD) who performed an incremental exercise test until exhaustion at baseline and after three months of training were included. Polymorphisms of the genes were detected using the invader assay. Genotype-phenotype association analyses were performed using ANCOVA. Different models for a genetic predisposition score (GPS) were constructed based on literature and own data and were related to baseline and response VO(2) scores. Carriers of the minor allele in the R23K polymorphism of the glucocorticoid receptor gene (GR) and the ciliary neurotrophic factor gene (CNTF) had a significantly higher increase in peakVO(2) after training (p < 0.05). Carriers of the minor allele (C34T) in the adenosine monophosphate deaminase (AMPD1) gene had a significantly lower relative increase (p < 0.05) in peakVO(2). GPS of data driven models were significantly associated with the increase in peakVO(2) after training. In CAD patients, suggestive associations were found in the GR, CNTF and the AMPD1 gene with an improved change in aerobic capacity after three months of training. Additionally data driven models with a genetic predisposition score (GPS) showed a significant predictive value for the increase in peakVO(2).

A genetic predisposition score for muscular endophenotypes predicts the increase in aerobic power after training: the CAREGENE study

PubMed Central

2011-01-01

Background It is widely accepted that genetic variability might explain a large part of the observed heterogeneity in aerobic capacity and its response to training. Significant associations between polymorphisms of different genes with muscular strength, anaerobic phenotypes and body composition have been reported. Muscular endophenotypes are positively correlated with aerobic capacity, therefore, we tested the association of polymorphisms in twelve muscular related genes on aerobic capacity and its response to endurance training. Methods 935 Coronary artery disease patients (CAD) who performed an incremental exercise test until exhaustion at baseline and after three months of training were included. Polymorphisms of the genes were detected using the invader assay. Genotype-phenotype association analyses were performed using ANCOVA. Different models for a genetic predisposition score (GPS) were constructed based on literature and own data and were related to baseline and response VO2 scores. Results Carriers of the minor allele in the R23K polymorphism of the glucocorticoid receptor gene (GR) and the ciliary neurotrophic factor gene (CNTF) had a significantly higher increase in peakVO2 after training (p < 0.05). Carriers of the minor allele (C34T) in the adenosine monophosphate deaminase (AMPD1) gene had a significantly lower relative increase (p < 0.05) in peakVO2. GPS of data driven models were significantly associated with the increase in peakVO2 after training. Conclusions In CAD patients, suggestive associations were found in the GR, CNTF and the AMPD1 gene with an improved change in aerobic capacity after three months of training. Additionally data driven models with a genetic predisposition score (GPS) showed a significant predictive value for the increase in peakVO2. PMID:21967077

Increased endothelial microparticles and oxidative stress at extreme altitude.

PubMed

Pichler Hefti, Jacqueline; Leichtle, Alexander; Stutz, Monika; Hefti, Urs; Geiser, Thomas; Huber, Andreas R; Merz, Tobias M

2016-04-01

Hypoxia and oxidative stress affect endothelial function. Endothelial microparticles (MP) are established measures of endothelial dysfunction and influence vascular reactivity. To evaluate the effects of hypoxia and antioxidant supplementation on endothelial MP profiles, a double-blind, placebo-controlled trial, during a high altitude expedition was performed. 29 participants were randomly assigned to a treatment group (n = 14), receiving vitamin E, C, A, and N-acetylcysteine daily, and a control group (n = 15), receiving placebo. Blood samples were obtained at 490 m (baseline), 3530, 4590, and 6210 m. A sensitive tandem mass spectrometry method was used to measure 8-iso-prostaglandin F2α and hydroxyoctadecadienoic acids as markers of oxidative stress. Assessment of MP profiles including endothelial activation markers (CD62+MP and CD144+MP) and cell apoptosis markers (phosphatidylserine+MP and CD31+MP) was performed using a standardized flow cytometry-based protocol. 15 subjects reached all altitudes and were included in the final analysis. Oxidative stress increased significantly at altitude. No statistically significant changes were observed comparing baseline to altitude measurements of phosphatidylserine expressing MP (p = 0.1718) and CD31+MP (p = 0.1305). Compared to baseline measurements, a significant increase in CD62+MP (p = 0.0079) and of CD144+MP was detected (p = 0.0315) at high altitudes. No significant difference in any MP level or oxidative stress markers were found between the treatment and the control group. Hypobaric hypoxia is associated with increased oxidative stress and induces a significant increase in CD62+ and CD144+MP, whereas phosphatidylserine+MP and CD31+MP remain unchanged. This indicates that endothelial activation rather than an apoptosis is the primary factor of hypoxia induced endothelial dysfunction.

Prediction of the diffuse-field transmission loss of interior natural-ventilation openings and silencers.

PubMed

Bibby, Chris; Hodgson, Murray

2017-01-01

The work reported here, part of a study on the performance and optimal design of interior natural-ventilation openings and silencers ("ventilators"), discusses the prediction of the acoustical performance of such ventilators, and the factors that affect it. A wave-based numerical approach-the finite-element method (FEM)-is applied. The development of a FEM technique for the prediction of ventilator diffuse-field transmission loss is presented. Model convergence is studied with respect to mesh, frequency-sampling and diffuse-field convergence. The modeling technique is validated by way of predictions and the comparison of them to analytical and experimental results. The transmission-loss performance of crosstalk silencers of four shapes, and the factors that affect it, are predicted and discussed. Performance increases with flow-path length for all silencer types. Adding elbows significantly increases high-frequency transmission loss, but does not increase overall silencer performance which is controlled by low-to-mid-frequency transmission loss.

Frequent Immediate Knowledge of Results Enhances the Increase of Throwing Velocity in Overarm Handball Performance.

PubMed

Štirn, Igor; Carruthers, Jamie; Šibila, Marko; Pori, Primož

2017-02-01

In the present study, the effect of frequent, immediate, augmented feedback on the increase of throwing velocity was investigated. An increase of throwing velocity of a handball set shot when knowledge of results was provided or not provided during training was compared. Fifty female and seventy-three male physical education students were assigned randomly to the experimental or control group. All participants performed two series of ten set shots with maximal effort twice a week for six weeks. The experimental group received information regarding throwing velocity measured by a radar gun immediately after every shot, whereas the control group did not receive any feedback. Measurements of maximal throwing velocity of an ordinary handball and a heavy ball were performed, before and after the training period and compared. Participants who received feedback on results attained almost a four times greater relative increase of the velocity of the normal ball (size 2) as compared to the same intervention when feedback was not provided (8.1 ± 3.6 vs. 2.7 ± 2.9%). The velocity increases were smaller, but still significant between the groups for throws using the heavy ball (5.1 ± 4.2 and 2.5 ± 5.8 for the experimental and control group, respectively). Apart from the experimental group throwing the normal ball, no differences in velocity change for gender were obtained. The results confirmed that training oriented towards an increase in throwing velocity became significantly more effective when frequent knowledge of results was provided.

Selective attention increases choice certainty in human decision making.

PubMed

Zizlsperger, Leopold; Sauvigny, Thomas; Haarmeier, Thomas

2012-01-01

Choice certainty is a probabilistic estimate of past performance and expected outcome. In perceptual decisions the degree of confidence correlates closely with choice accuracy and reaction times, suggesting an intimate relationship to objective performance. Here we show that spatial and feature-based attention increase human subjects' certainty more than accuracy in visual motion discrimination tasks. Our findings demonstrate for the first time a dissociation of choice accuracy and certainty with a significantly stronger influence of voluntary top-down attention on subjective performance measures than on objective performance. These results reveal a so far unknown mechanism of the selection process implemented by attention and suggest a unique biological valence of choice certainty beyond a faithful reflection of the decision process.

Disintegration performance of renal multivitamin supplements.

PubMed

Stamatakis, M K; Meyer-Stout, P J

1999-04-01

Vitamins have traditionally been regulated as dietary supplements and have not been required to meet the same rigorous product quality performance standards as drug products. Impaired product performance, such as failure to disintegrate and/or dissolve in the gastrointestinal tract, could limit the absorption of vitamins. Furthermore, patients with renal disease have been reported to experience a wide range in gastrointestinal pH, which could influence a product's performance. The purpose of this study was to determine the effect of pH on the in vitro disintegration of renal multivitamin supplements. Products were studied using the United States Pharmacopeial Convention standard disintegration apparatus. Products were tested in simulated gastric fluid, neutral fluid, and intestinal fluid. Product failure was defined as two or more individual tablets or capsules failing to disintegrate completely within compendial limits. Of 11 products tested, 4 products failed the disintegration study test in all pH conditions. Sixty-four percent of the products showed statistically significant differences in disintegration time (DT) based on pH. As pH increased, time to disintegration increased. The DT of commercially available renal multivitamin supplements was highly variable. Poorest product performance was shown in simulated intestinal fluid. The pH significantly affected in vitro disintegration in greater than half the products tested. How this affects dissolution and in vivo performance has yet to be studied.

Investigation of the role of flocculation conditions in recuperative thickening on dewatering performance and biogas production.

PubMed

Cobbledick, Jeffrey; Zhang, Victor; Rollings-Scattergood, Sasha; Latulippe, David R

2017-11-01

There is considerable interest in recuperative thickening (RT), the recycling of partially digested solids in an anaerobic digester outlet stream back into the incoming feed, as a 'high-performance' process to increase biogas production, increase system capacity, and improve biosolids stabilization. While polymer flocculation is commonly used in full-scale RT operations, no studies have investigated the effect of flocculation conditions on RT process performance. Our goal was to investigate the effect of polymer type and dosage conditions on dewatering performance and biogas production in a lab-scale RT system. The type of polymer flocculant significantly affected dewatering performance. For example, the 440 LH polymer (low molecular weight (MW) polyacrylamide) demonstrated lower capillary suction time (CST) and filtrate total suspended solids (TSS) values than the C-6267 polymer (high MW polyacrylamide). An examination of the dewatering performance of RT digesters with different polymers found a strong correlation between CST and filtrate TSS. The type of polymer flocculant had no significant effect on biogas productivity or composition; the methane content was greater than 60% in good agreement with typical results. The optimization of the polymer flocculation conditions is a critical task for which the lab-scale RT system used in this work is ideally suited.

The effects of warning cues and attention-capturing stimuli on the sustained attention to response task.

PubMed

Finkbeiner, Kristin M; Wilson, Kyle M; Russell, Paul N; Helton, William S

2015-04-01

Performance on the sustained attention to response task (SART) is often characterized by a speed-accuracy trade-off, and SART performance may be influenced by strategic factors (Head and Helton Conscious Cogn 22: 913-919, 2013). Previous research indicates a significant difference between reliable and unreliable warning cues on response times and errors (commission and omission), suggesting that SART tasks are influenced by strategic factors (Helton et al. Conscious Cogn 20: 1732-1737, 2011; Exp Brain Res 209: 401-407, 2011). With regards to warning stimuli, we chose to use cute images (exhibiting infantile features) during a SART, as previous literature indicates cute images cause participants to engage attention. If viewing cute things makes the viewer exert more attention than normal, then exposure to cute stimuli during the SART should improve performance if SART performance is a measure of perceptual coupling. Reliable warning cues were shown to reduce both response time and errors of commission, and increase errors of omission, relative to unreliable warning cues. Cuteness of the warning stimuli, however, had no significant effect on SART performance. These results suggest the importance of strategic factors in SART performance, not increased attention, and add to the growing literature which suggests the SART is not a good measure of sustained attention, vigilance or perceptual coupling.

Effect of Advanced Trauma Life Support program on medical interns' performance in simulated trauma patient management.

PubMed

Ahmadi, Koorosh; Sedaghat, Mohammad; Safdarian, Mahdi; Hashemian, Amir-Masoud; Nezamdoust, Zahra; Vaseie, Mohammad; Rahimi-Movaghar, Vafa

2013-01-01

Since appropriate and time-table methods in trauma care have an important impact on patients'outcome, we evaluated the effect of Advanced Trauma Life Support (ATLS) program on medical interns' performance in simulated trauma patient management. A descriptive and analytical study before and after the training was conducted on 24 randomly selected undergraduate medical interns from Imam Reza Hospital in Mashhad, Iran. On the first day, we assessed interns' clinical knowledge and their practical skill performance in confronting simulated trauma patients. After 2 days of ATLS training, we performed the same study and evaluated their score again on the fourth day. The two findings, pre- and post- ATLS periods, were compared through SPSS version 15.0 software. P values less than 0.05 were considered statistically significant. Our findings showed that interns'ability in all the three tasks improved after the training course. On the fourth day after training, there was a statistically significant increase in interns' clinical knowledge of ATLS procedures, the sequence of procedures and skill performance in trauma situations (P less than 0.001, P equal to 0.016 and P equal to 0.01 respectively). ATLS course has an important role in increasing clinical knowledge and practical skill performance of trauma care in medical interns.

Dark chocolate supplementation reduces the oxygen cost of moderate intensity cycling.

PubMed

Patel, Rishikesh Kankesh; Brouner, James; Spendiff, Owen

2015-01-01

Dark chocolate (DC) is abundant in flavanols which have been reported to increase the bioavailability and bioactivity of nitric oxide (NO). Increasing NO bioavailability has often demonstrated reduced oxygen cost and performance enhancement during submaximal exercise. Nine moderately-trained male participants volunteered to undertake baseline (BL) measurements that comprised a cycle V̇O(2max) test followed by cycling at 80% of their established gas exchange threshold (GET) for 20-min and then immediately followed by a two-minute time-trial (TT). Using a randomised crossover design participants performed two further trials, two weeks apart, with either 40 g of DC or white chocolate (WC) being consumed daily. Oxygen consumption, RER, heart rate and blood lactate (BLa) were measured during each trial. DC consumption increased GET and TT performance compared to both BL and WC (P < 0.05). DC consumption increased V̇O(2max) by 6% compared to BL (P < 0.05), but did not reach statistical significance compared to WC. There were no differences in the moderate-intensity cycling for V̇O₂, RER, BLa and heart rate between conditions, although, V̇O₂ and RER exhibited consistently lower trends following DC consumption compared to BL and WC, these did not reach statistical significance. Chronic supplementation with DC resulted in a higher GET and enhanced TT performance. Consequently, ingestion of DC reduced the oxygen cost of moderate intensity exercise and may be an effective ergogenic aid for short-duration moderate intensity exercise.

Perceptual learning improves visual performance in juvenile amblyopia.

PubMed

Li, Roger W; Young, Karen G; Hoenig, Pia; Levi, Dennis M

2005-09-01

To determine whether practicing a position-discrimination task improves visual performance in children with amblyopia and to determine the mechanism(s) of improvement. Five children (age range, 7-10 years) with amblyopia practiced a positional acuity task in which they had to judge which of three pairs of lines was misaligned. Positional noise was produced by distributing the individual patches of each line segment according to a Gaussian probability function. Observers were trained at three noise levels (including 0), with each observer performing between 3000 and 4000 responses in 7 to 10 sessions. Trial-by-trial feedback was provided. Four of the five observers showed significant improvement in positional acuity. In those four observers, on average, positional acuity with no noise improved by approximately 32% and with high noise by approximately 26%. A position-averaging model was used to parse the improvement into an increase in efficiency or a decrease in equivalent input noise. Two observers showed increased efficiency (51% and 117% improvements) with no significant change in equivalent input noise across sessions. The other two observers showed both a decrease in equivalent input noise (18% and 29%) and an increase in efficiency (17% and 71%). All five observers showed substantial improvement in Snellen acuity (approximately 26%) after practice. Perceptual learning can improve visual performance in amblyopic children. The improvement can be parsed into two important factors: decreased equivalent input noise and increased efficiency. Perceptual learning techniques may add an effective new method to the armamentarium of amblyopia treatments.

Characterization of Steroid Receptor RNA Activator Protein Function in Modulating the Estrogen Signaling Pathway

DTIC Science & Technology

2008-03-01

official Department of the Army position, policy or decision unless so designated by other documentation. REPORT DOCUMENTATION PAGE Form...control). Four experiments were performed and the average modifications calculated). A significant (pɘ.05, Student’s t- test ) average increase of 90% in...assessed by TP-PCR at t: 24 h, 48 h, and 72h. We found a significant increase (2.5 fold, pɘ.05, Student’s t- test ) in relative intron-1 retention was

Innovative Double Bypass Engine for Increased Performance

NASA Astrophysics Data System (ADS)

Manoharan, Sanjivan

Engines continue to grow in size to meet the current thrust requirements of the civil aerospace industry. Large engines pose significant transportation problems and require them to be split in order to be shipped. Thus, large amounts of time have been spent in researching methods to increase thrust capabilities while maintaining a reasonable engine size. Unfortunately, much of this research has been focused on increasing the performance and efficiencies of individual components while limited research has been done on innovative engine configurations. This thesis focuses on an innovative engine configuration, the High Double Bypass Engine, aimed at increasing fuel efficiency and thrust while maintaining a competitive fan diameter and engine length. The 1-D analysis was done in Excel and then compared to the results from Numerical Propulsion Simulation System (NPSS) software and were found to be within 4% error. Flow performance characteristics were also determined and validated against their criteria.

Cardiorespiratory Coordination in Repeated Maximal Exercise

PubMed Central

Garcia-Retortillo, Sergi; Javierre, Casimiro; Hristovski, Robert; Ventura, Josep L.; Balagué, Natàlia

2017-01-01

Increases in cardiorespiratory coordination (CRC) after training with no differences in performance and physiological variables have recently been reported using a principal component analysis approach. However, no research has yet evaluated the short-term effects of exercise on CRC. The aim of this study was to delineate the behavior of CRC under different physiological initial conditions produced by repeated maximal exercises. Fifteen participants performed 2 consecutive graded and maximal cycling tests. Test 1 was performed without any previous exercise, and Test 2 6 min after Test 1. Both tests started at 0 W and the workload was increased by 25 W/min in males and 20 W/min in females, until they were not able to maintain the prescribed cycling frequency of 70 rpm for more than 5 consecutive seconds. A principal component (PC) analysis of selected cardiovascular and cardiorespiratory variables (expired fraction of O2, expired fraction of CO2, ventilation, systolic blood pressure, diastolic blood pressure, and heart rate) was performed to evaluate the CRC defined by the number of PCs in both tests. In order to quantify the degree of coordination, the information entropy was calculated and the eigenvalues of the first PC (PC1) were compared between tests. Although no significant differences were found between the tests with respect to the performed maximal workload (Wmax), maximal oxygen consumption (VO2 max), or ventilatory threshold (VT), an increase in the number of PCs and/or a decrease of eigenvalues of PC1 (t = 2.95; p = 0.01; d = 1.08) was found in Test 2 compared to Test 1. Moreover, entropy was significantly higher (Z = 2.33; p = 0.02; d = 1.43) in the last test. In conclusion, despite the fact that no significant differences were observed in the conventionally explored maximal performance and physiological variables (Wmax, VO2 max, and VT) between tests, a reduction of CRC was observed in Test 2. These results emphasize the interest of CRC evaluation in the assessment and interpretation of cardiorespiratory exercise testing. PMID:28638349

Effect of progressive resistance exercise with neuromuscular joint facilitation on the dynamic balance performance of junior soccer players.

PubMed

Wang, Hongzhao; Huo, Ming; Guan, Peipei; Onoda, Ko; Chen, Di; Huang, Qiuchen; Maruyama, Hitoshi

2015-11-01

[Purpose] The aim of this study was to investigate the change in dynamic balance performance of junior soccer players after progressive resistance treatment with neuromuscular joint facilitation (NJF). [Subjects] The subjects were 14 healthy males who were divided into two groups, namely the NJF and control groups. The NJF group consisted of 8 subjects, and the control group consisted of 6 subjects. [Methods] The participants in the NJF group received NJF progressive resistance treatment. Dynamic balance performance was measured before and after 3 weeks of exercise. [Results] Significant improvement in dynamic balance performance was observed both in the NJF and control groups. In the NJF group, dynamic balance performance was significantly increased compared with that in the control group. [Conclusion] The NJF intervention shortened movement time, which implies that NJF is effective for dynamic balance performance.

The Effects of Working Memory on Brain-Computer Interface Performance

PubMed Central

Sprague, Samantha A.; McBee, Matthew; Sellers, Eric W.

2015-01-01

Objective The purpose of the present study is to evaluate the relationship between working memory and BCI performance. Methods Participants took part in two separate sessions. The first session consisted of three computerized tasks. The LSWM was used to measure working memory, the TPVT was used to measure general intelligence, and the DCCS was used to measure executive function, specifically cognitive flexibility. The second session consisted of a P300-based BCI copy-spelling task. Results The results indicate that both working memory and general intelligence are significant predictors of BCI performance. Conclusions This suggests that working memory training could be used to improve performance on a BCI task. Significance Working memory training may help to reduce a portion of the individual differences that exist in BCI performance allowing for a wider range of users to successfully operate the BCI system as well as increase the BCI performance of current users. PMID:26620822

The influence of in-game emotions on basketball performance.

PubMed

Uphill, Mark; Groom, Ryan; Jones, Marc

2014-01-01

This study examined the influence of emotions on performance in basketball. Six female basketball players were videotaped in six games. Frequency of performance behaviours was recorded minute-by-minute and indices of successful (SGI) and unsuccessful (UGI) game involvement derived for each player. Post-game, players reported the intensity of experienced emotions (anger, anxiety, embarrassment, excitement and happiness), and the time of the eliciting incident. The only emotion revealed as a significant predictor of SGI was happiness; both anger and embarrassment were significant predictors of increased UGI. Consideration of individual player analyses suggests that there is variation in the magnitude of the influence of emotions on performance and the extent to which this influence was helpful or harmful to performance. The study provides evidence that emotions are associated with changes in game behaviours in competition. Implications for further research examining the emotion-performance relationship are discussed.

Dystocia in Friesian cows and its effects on postpartum reproductive performance and milk production

PubMed Central

Shamiah, Sh. M.; El-Hamd, M. A. Abu; Shitta, A. A.; El-Din, M. A. Tag

2010-01-01

A total of 1,243 records for 585 dairy Friesian cows from 1997–2004 were used to study the factors affecting dystocia and its effects on reproductive performance and milk production. The overall incidence of dystocia was 6.9%. The percentage of dystocia decreased with increasing live body weight, age, and parity of cows (P < 0.05); however, it increased with increasing birth weight of calves (P < 0.05). The highest percentage of dystocia was detected in winter season, but the least percentage was in summer season (P < 0.05). The percentage of incidence of dystocia was significantly (P < 0.05) higher with winter feeding compared to summer ration (8.2% vs. 5.1%). The percentage of incidence of dystocia was significantly (P < 0.05) higher with twinning than single calving (15.5% vs. 6.5%), while not significantly affected by the sex of born calves. Incidence of dystocia had adverse effects on reproductive performance and milk yield. The service interval, service period, days open, and calving interval were significantly (P < 0.05) longer in cows afflicted with dystocia compared to normal cows. The conception rate was lower (P < 0.05), but the number of service per conception was higher (P < 0.05) in cows afflicted with dystocia compared to normal cows (60.5% vs. 73.0% and 3.4 vs. 2.7, respectively). Average daily milk yield was lower (P < 0.05) by 1 kg for cows with incidence of dystocia compared to normal cows. PMID:20835761

Functional aspects of treatment with implant-supported single crowns: a quality control study in subjects with tooth agenesis.

PubMed

Goshima, Kenichi; Lexner, Michala O; Thomsen, Carsten Eckhart; Miura, Hiroyuki; Gotfredsen, Klaus; Bakke, Merete

2010-01-01

No comprehensive patient-centered and clinical evaluations of the functional effect of treatment with implant-supported single crowns (ISSC) have been reported previously. To investigate whether and how treatment with ISSC affects masticatory function and Oral Health-Related Quality of Life (OHRQoL) in subjects with tooth agenesis. In nine females and nine males (32 + or - 10 years) with agenesis treated with one to four ISSC (68% in the premolar region), the treatment effect and masticatory function were assessed. The evaluation was performed first after implant placement shortly before crown cementation, and again 1 month after cementation. It consisted of questionnaires [including Oral Health Impact Profile (OHIP-49)] and functional examination with plastic strips, the Dental Prescale Film and the Occluzer system, Xylitol color-changeable gum and slices of Granny Smith apple. The patients' satisfaction with treatment was high and they experienced a significant overall improvement in their OHRQoL (on average 13% reduction in the total OHIP scores). The cementation of the crowns was associated with a significant increase in the number of near occlusal tooth contacts, contact area, bite force, and masticatory ability and performance. Correspondingly, there was a significant, positive correlation between the number of tooth contacts and (1) occlusal contact area, (2) bite force, and (3) masticatory performance. Treatment with ISSCs in subjects with tooth agenesis significantly increased masticatory function subjectively and clinically as well as OHRQoL. However, as the functional parameters before replacement of the teeth corresponded to values in subjects with complete dentitions, the functional importance of the increase may be questioned.

Detrimental effects of commercial zinc oxide and silver nanomaterials on bacterial populations and performance of wastewater systems

NASA Astrophysics Data System (ADS)

Mboyi, Anza-vhudziki; Kamika, Ilunga; Momba, MaggyN. B.

2017-08-01

The widespread use of commercial nanomaterials (NMs) in consumer products has raised environmental concerns as they can enter and affect the efficiency of the wastewater treatment plants. In this study the effect of various concentrations of zinc oxide NMs (nZnO) and silver NMs (nAg) on the selected wastewater bacterial species (Bacillus licheniformis, Brevibacillus laterosporus and Pseudomonas putida) was ascertained at different pH levels (pH 2, 7 and 10). Lethal concentrations (LC) of NMs and parameters such as chemical oxygen demand (COD) and dissolved oxygen (DO) were taken into consideration to assess the performance of a wastewater batch reactor. Bacterial isolates were susceptible to varying concentrations of both nZnO and nAg at pH 2, 7 and 10. It was found that a change in pH did not significantly affect the toxicity of test NMs towards target bacterial isolates. All bacterial species were significantly inhibited (p < 0.05) in the presence of 0.65 g/L of nZnO and nAg. In contrast, there was no significant difference (p > 0.05) in COD removal in the presence of increasing concentrations of NMs, which resulted in increasing releases of COD. Noticeably, there was no significant difference (p > 0.05) in the decrease in DO uptake in the presence of increasing NM concentrations for all bacterial isolates. The toxic effects of the target NMs on bacterial populations in wastewater may negatively impact the performance of biological treatment processes and may thus affect the efficiency of wastewater treatment plants in producing effluent of high quality.

Contribution of posture to anorectal manometric measurements: are the measurements in left-lateral position physiologic?

PubMed

Thekkinkattil, Dinesh K; Lim, Michael K; Nicholls, Marcus J; Sagar, Peter M; Finan, Paul J; Burke, Dermot A

2007-12-01

Anorectal manometry is commonly used to investigate fecal incontinence. Traditional practice dictates that measurements are performed with the patient in the left-lateral position however, episodes of fecal incontinence usually occur in the erect position. The influence of erect posture on anorectal manometry has not been studied. We examined the contribution of posture to commonly measured variables during manometry by performing assessment in the left-lateral position and the erect posture. Maximum mean resting pressure, vector volumes, and resting pressure gradient were compared. Complete data were available for 172 patients. Median age was 55 (interquartile range, 44-65) years. Thirty-seven (22 percent) patients were continent, and 135 (78 percent) were incontinent. Both resting pressure and vector volume increased significantly in the erect position for both continent (P = 0.008 and 0.001, respectively) and incontinent (P = 0.001 for both) patients. A significant negative correlation was seen between severity of incontinence and resting pressure in the erect posture and amount of change in maximum mean resting pressure from left-lateral to erect posture (Spearman coefficients = -0.203, -0.211, and P = 0.013, 0.017, respectively) but not with maximum mean resting pressure in the left-lateral position (Spearman coefficient = -0.119; P = 0.164). Our study shows significant increase in measurements of manometric variables in the erect position. The increase may be related to anal cushions, which have a significant role in this position. The measurements in erect posture are better correlated with severity of incontinence and may be a more physiologic method of performing anorectal manometry.

The relationship between performance and flow state in tennis competition.

PubMed

Koehn, S; Morris, T

2012-08-01

The study aimed to examine 1) the validity of the nine-factor flow model in tennis competition; 2) differences in flow state between athletes who won or lost their competition match; 3) the link between flow and subjective performance; and 4) flow dimensions as predictors of performance outcome The sample consisted of 188 junior tennis players (115 male, 73 female) between 12 and 18 years of age. Participants' performance was recorded during junior ranking-list tournaments. Following the completion of a tennis competition match, participants completed the Flow State Scale-2 and a subjective performance outcome measure. Acceptable flow model fit indices of CFI, TLI, SRMR, and RMSEA were only found for winning athletes. The group of winning athletes scored significantly higher on all nine flow dimensions, except time transformation, than losing athletes, showing statistically significant differences for challenge-skills balance, clear goals, sense of control, and autotelic experience. Significant correlation coefficients were found between flow state and subjective performance assessments. The binary logistic regression revealed concentration on the task and sense of control to be significant predictors of performance outcome. The predictor variables explained 13% of the variance in games won. The study showed that athletes who win or lose perceived flow state differently. Studies using retrospective assessments need to be aware that subjective experience could be biased by performance outcomes. Pinpointing psychological variables and their impact on ecologically valid measures, such as performance results, would support the development of effective intervention studies to increase performance in sport competition.

Brachioplasty outcomes: a review of a multipractice cohort.

PubMed

Zomerlei, Terri A; Neaman, Keith C; Armstrong, Shannon D; Aitken, Marguerite E; Cullen, William T; Ford, Ronald D; Renucci, John D; VanderWoude, Douglas L

2013-04-01

Upper arm deformities secondary to massive weight loss or senile elastosis have led to an increased demand for aesthetic contouring procedures such as brachioplasty. The records of all patients who underwent a brachioplasty procedure from a multipractice medical center were reviewed. Outcomes measured included patient demographics, operative interventions, and postoperative course. Ninety-six patients were analyzed. Fifty-three patients (55.2 percent) underwent a concomitant procedure, with 53.1 percent undergoing arm liposuction at the time of brachioplasty. Major and minor complications rates were 17.7 percent and 44.8 percent, respectively. Common complications included hypertrophic scarring (24.0 percent) and infection (14.6 percent). The total revision rate was 22.9 percent, with residual contour deformity (40.9 percent of revisions) and hypertrophic scarring (36.4 percent of revisions) representing the most common causes for revision. Patients who underwent a previous bariatric procedure were at an increased risk of developing a major complication (p = 0.02). Concomitant upper arm liposuction and concomitant procedures were not associated with a significantly increased complication rate. Brachioplasty, despite being an effective treatment for contour irregularities of the upper arm, is associated with significant revision and complication rates. Post-bariatric surgery patients should be informed of the potential for increased complications. Additional procedures performed at the time of brachioplasty do not significantly increase complications. Liposuction of the upper arm can be performed safely in conjunction with brachioplasty.

Effects of cognitive stimulation with a self-modeling video on time to exhaustion while running at maximal aerobic velocity: a pilot study.

PubMed

Hagin, Vincent; Gonzales, Benoît R; Groslambert, Alain

2015-04-01

This study assessed whether video self-modeling improves running performance and influences the rate of perceived exertion and heart rate response. Twelve men (M age=26.8 yr., SD=6; M body mass index=22.1 kg.m(-2), SD=1) performed a time to exhaustion running test at 100 percent maximal aerobic velocity while focusing on a video self-modeling loop to synchronize their stride. Compared to the control condition, there was a significant increase of time to exhaustion. Perceived exertion was lower also, but there was no significant change in mean heart rate. In conclusion, the video self-modeling used as a pacer apparently increased endurance by decreasing perceived exertion without affecting the heart rate.

Effect of Increasing Total Solids Contents on Anaerobic Digestion of Food Waste under Mesophilic Conditions: Performance and Microbial Characteristics Analysis

PubMed Central

Jin, Jingwei; Dai, Xiaohu

2014-01-01

The total solids content of feedstocks affects the performances of anaerobic digestion and the change of total solids content will lead the change of microbial morphology in systems. In order to increase the efficiency of anaerobic digestion, it is necessary to understand the role of the total solids content on the behavior of the microbial communities involved in anaerobic digestion of organic matter from wet to dry technology. The performances of mesophilic anaerobic digestion of food waste with different total solids contents from 5% to 20% were compared and the microbial communities in reactors were investigated using 454 pyrosequencing technology. Three stable anaerobic digestion processes were achieved for food waste biodegradation and methane generation. Better performances mainly including volatile solids reduction and methane yield were obtained in the reactors with higher total solids content. Pyrosequencing results revealed significant shifts in bacterial community with increasing total solids contents. The proportion of phylum Chloroflexi decreased obviously with increasing total solids contents while other functional bacteria showed increasing trend. Methanosarcina absolutely dominated in archaeal communities in three reactors and the relative abundance of this group showed increasing trend with increasing total solids contents. These results revealed the effects of the total solids content on the performance parameters and the behavior of the microbial communities involved in the anaerobic digestion of food waste from wet to dry technologies. PMID:25051352

Effect of increasing total solids contents on anaerobic digestion of food waste under mesophilic conditions: performance and microbial characteristics analysis.

PubMed

Yi, Jing; Dong, Bin; Jin, Jingwei; Dai, Xiaohu

2014-01-01

The total solids content of feedstocks affects the performances of anaerobic digestion and the change of total solids content will lead the change of microbial morphology in systems. In order to increase the efficiency of anaerobic digestion, it is necessary to understand the role of the total solids content on the behavior of the microbial communities involved in anaerobic digestion of organic matter from wet to dry technology. The performances of mesophilic anaerobic digestion of food waste with different total solids contents from 5% to 20% were compared and the microbial communities in reactors were investigated using 454 pyrosequencing technology. Three stable anaerobic digestion processes were achieved for food waste biodegradation and methane generation. Better performances mainly including volatile solids reduction and methane yield were obtained in the reactors with higher total solids content. Pyrosequencing results revealed significant shifts in bacterial community with increasing total solids contents. The proportion of phylum Chloroflexi decreased obviously with increasing total solids contents while other functional bacteria showed increasing trend. Methanosarcina absolutely dominated in archaeal communities in three reactors and the relative abundance of this group showed increasing trend with increasing total solids contents. These results revealed the effects of the total solids content on the performance parameters and the behavior of the microbial communities involved in the anaerobic digestion of food waste from wet to dry technologies.

Effects of carbohydrate combined with caffeine on repeated sprint cycling and agility performance in female athletes

PubMed Central

2014-01-01

Background Caffeine (CAF) has been shown to improve performance during early phase of repeated sprint exercise; however some studies show that CAF also increases the magnitude of physical stress represented by augmented blood lactate, glucose, and cortisol concentrations during latter phase of repeated sprint exercise. No studies have investigated the efficacy of combined carbohydrate (CHO) and CAF consumption during repeated sprint exercise (RSE) in female athletes. Thus, the purpose of this study was to investigate the effects of CAF with CHO supplementation on RSE and agility. Methods Eleven female athletes completed four experimental trials performed 7 d apart in a double-blind, randomized, and counter-balanced crossover design. Treatments included CAF + PLA (placebo), CAF + CHO, PLA + CHO, and PLA + PLA. Participants ingested capsules containing 6 mg · kg−1 of CAF or PLA 60-min prior to RSE, and 0.8 g · kg−1 of CHO solution or PLA immediately before the RSE, which consisted of ten sets of 5 × 4-s sprints on the cycle ergometer with 20-s active recovery. The agility T-test (AT-test) was performed before and after the RSE. Blood samples were acquired to assess glucose, lactate, testosterone, and cortisol. Results During Set 6 of RSE, peak power and mean power were significantly higher in PLA + CHO than those in CAF + PLA and PLA + PLA, respectively (p < .05). Total work was significantly increased by 4.8% and 5.9% with PLA + CHO than those of CAF + CHO and CAF + PLA during Set 3. PLA + CHO also increased total work more than CAF + PLA and PLA + PLA did during Set 6 (p < .05). No significant differences in AT-test performance either before or after the RSE were occurred among treatments (p > .05). Blood lactate and glucose concentrations were significantly higher under CAF + CHO, CAF + PLA, and PLA + CHO versus PLA + PLA (p < .05), but no differences in testosterone or cortisol levels were found (p > .05). Conclusions Findings indicate that CAF + PLA or CAF + CHO ingestion did not improve repeated sprint performance with short rest intervals or agility. However, CHO ingested immediately prior to exercise provided a small but significant benefit on RSE performance in female athletes. PMID:24855458

Increased seawater temperature increases the abundance and alters the structure of natural Vibrio populations associated with the coral Pocillopora damicornis

PubMed Central

Tout, Jessica; Siboni, Nachshon; Messer, Lauren F.; Garren, Melissa; Stocker, Roman; Webster, Nicole S.; Ralph, Peter J.; Seymour, Justin R.

2015-01-01

Rising seawater temperature associated with global climate change is a significant threat to coral health and is linked to increasing coral disease and pathogen-related bleaching events. We performed heat stress experiments with the coral Pocillopora damicornis, where temperature was increased to 31°C, consistent with the 2–3°C predicted increase in summer sea surface maxima. 16S rRNA amplicon sequencing revealed a large shift in the composition of the bacterial community at 31°C, with a notable increase in Vibrio, including known coral pathogens. To investigate the dynamics of the naturally occurring Vibrio community, we performed quantitative PCR targeting (i) the whole Vibrio community and (ii) the coral pathogen Vibrio coralliilyticus. At 31°C, Vibrio abundance increased by 2–3 orders of magnitude and V. coralliilyticus abundance increased by four orders of magnitude. Using a Vibrio-specific amplicon sequencing assay, we further demonstrated that the community composition shifted dramatically as a consequence of heat stress, with significant increases in the relative abundance of known coral pathogens. Our findings provide quantitative evidence that the abundance of potential coral pathogens increases within natural communities of coral-associated microbes as a consequence of rising seawater temperature and highlight the potential negative impacts of anthropogenic climate change on coral reef ecosystems. PMID:26042096

Public health systems under attack in Canada: Evidence on public health system performance challenges arbitrary reform.

PubMed

Guyon, Ak'ingabe; Perreault, Robert

2016-10-20

Public health is currently being weakened in several Canadian jurisdictions. Unprecedented and arbitrary cuts to the public health budget in Quebec in 2015 were a striking example of this. In order to support public health leaders and citizens in their capacity to advocate for evidence-informed public health reforms, we propose a knowledge synthesis of elements of public health systems that are significantly associated with improved performance. Research consistently and significantly associates four elements of public health systems with improved productivity: 1) increased financial resources, 2) increased staffing per capita, 3) population size between 50,000 and 500,000, and 4) specific evidence-based organizational and administrative features. Furthermore, increased financial resources and increased staffing per capita are significantly associated with improved population health outcomes. We contend that any effort at optimization of public health systems should at least be guided by these four evidence-informed factors. Canada already has existing capacity in carrying out public health systems and services research. Further advancement of our academic and professional expertise on public health systems will allow Canadian public health jurisdictions to be inspired by the best public health models and become stronger advocates for public health's resources, interventions and outcomes when they need to be celebrated or defended.

Shoe midsole longitudinal bending stiffness and running economy, joint energy, and EMG.

PubMed

Roy, Jean-Pierre R; Stefanyshyn, Darren J

2006-03-01

It has been shown that mechanical energy is dissipated at the metatarsophalangeal (MTP) joint during running and jumping. Furthermore, increasing the longitudinal bending stiffness of the midsole significantly reduced the energy dissipated at the MTP joint and increased jump performance. It was hypothesized that increasing midsole longitudinal bending stiffness would also lead to improvements in running economy. This study investigated the influence of midsole longitudinal bending stiffness on running economy (performance variable) and evaluated the local effects on joint energetics and muscular activity. Carbon fiber plates were inserted into running shoe midsoles and running economy, joint energy, and electromyographic (EMG) data were collected on 13 subjects. Approximately a 1% metabolic energy savings was observed when subjects ran in a stiff midsole relative to the control midsole. Subjects with a greater body mass had a greater decrease in oxygen consumption rates in the stiff midsole relative to the control midsole condition. The stiffer midsoles showed no significant differences in energy absorption at the MTP joint compared with the control shoe. Finally, no significant changes were observed in muscular activation. Increasing midsole longitudinal bending stiffness led to improvements in running economy, yet the underlying mechanisms that can be attributed to this improvement are still not fully understood.

Influence of Dietary Copper on Serum Growth-Related Hormone Levels and Growth Performance of Weanling Pigs.

PubMed

Wang, Jianguo; Zhu, Xiaoyan; Guo, Yazhou; Wang, Zhe; Zhao, Baoyu; Yin, Yunhou; Liu, Guowen

2016-07-01

To investigate the effect of dietary copper on serum growth-related hormones levels and growth performance, a total of 60 weanling pigs were randomly assigned to six groups each containing 10 pigs, fed on basal diets supplemented with 0 (control), 100, 150, 200, 250, and 300 mg/kg copper sulfate for 80 days, respectively. The average daily gain (ADG), feed to gain ratio (F/G), feed intake and serum growth hormone (GH), insulin (INS), insulin-like growth factor 1 (IGF-1), and insulin-like growth factor-binding protein 3 (IGFBP-3) levels were detected at interval of 20 days. The results revealed that ADG, and serum GH, INS, IGF-1, and IGFBP-3 concentrations were increased significantly in the pigs fed on diets added with 100, 150, 200, 250, and 300 mg/kg copper sulfate. Meanwhile, in the pigs supplemented with 250 mg/kg copper sulfate, ADG was increased significantly from the 40th to the 60th day of the experiment (P < 0.01), and the levels of GH, INS, IGF-1, and IGFBP-3 in serum were elevated significantly from the 20th to the 40th day of the experiment (P < 0.01). It is concluded that effects of copper supplemented in the diet on the growth of pigs were related to the increasing levels of GH, INS, IGF-1, and IGFBP-3 in serum which were induced by copper. High dietary copper increase the concentrations of growth-related hormones in serum, resulting in improving the growth performance of weanling pigs.

Macular thickness and volume after uncomplicated phacoemulsification surgery evaluated by optical coherence tomography. A one-year follow-up.

PubMed

Kecik, Dariusz; Makowiec-Tabernacka, Marta; Golebiewska, Joanna; Moneta-Wielgos, Joanna; Kasprzak, Jan

2009-01-01

To evaluate changes in the macular thickness and volume using optical coherence tomography in patients after phacoemulsification and intracapsular implantation of a foldable intraocular lens. The study included 82 patients (37 males and 45 females) after phacoemulsification and intracapsular implantaion of the same type of a foldable intraocular lens, without any other eye disease. Phacoemulsification was performed with an INFINITI machine. In all patients, macular thickness and volume were measured with an optical coherence tomograph (Stratus OCT) using the Fast Macular Thickness Map. The OCT evaluation was performed on days 1, 7, 30 and 90 postoperatively. In 58 patients (71%), it was additionally performed at 12 months after surgery and in 52 patients (63%) the macular parameters in the healthy and operated eyes were compared. A statistically significant increase in the minimal retinal thickness was observed on days 30 (p<0.0005) and 90 (p<0.005) postoperatively compared to post-operative day 1. A statistically significant increase in the foveal volume was seen on days 30 (p<0.00005) and 90 (p<0.0005). A statistically significant increase in the volume of the entire macula was found on days 7, 30 and 90 (p<0.00005). Uncomplicated cataract phacoemulsification is followed by increases in the central retinal thickness, foveal volume and volume of the entire macula on days 30 and 90 and at 12 months postoperatively. Further observation of patients is required to confirm whether the macular parameters will return to their values on day 1 postoperatively and if so, when this will occur.

Influence of capsaicin infusion on secondary peristalsis in patients with gastroesophageal reflux disease

PubMed Central

Yi, Chih-Hsun; Lei, Wei-Yi; Hung, Jui-Sheng; Liu, Tso-Tsai; Chen, Chien-Lin; Pace, Fabio

2016-01-01

AIM To determine whether capsaicin infusion could influence heartburn perception and secondary peristalsis in patients with gastroesophageal reflux disease (GERD). METHODS Secondary peristalsis was performed with slow and rapid mid-esophageal injections of air in 10 patients with GERD. In a first protocol, saline and capsaicin-containing red pepper sauce infusions were randomly performed, whereas 2 consecutive sessions of capsaicin-containing red pepper sauce infusions were performed in a second protocol. Tested solutions including 5 mL of red pepper sauce diluted with 15 mL of saline and 20 mL of 0.9% saline were infused into the mid-esophagus via the manometric catheter at a rate of 10 mL/min with a randomized and double-blind fashion. During each study protocol, perception of heartburn, threshold volumes and peristaltic parameters for secondary peristalsis were analyzed and compared between different stimuli. RESULTS Infusion of capsaicin significantly increased heartburn perception in patients with GERD (P < 0.001), whereas repeated capsaicin infusion significantly reduced heartburn perception (P = 0.003). Acute capsaicin infusion decreased threshold volume of secondary peristalsis (P = 0.001) and increased its frequency (P = 0.01) during rapid air injection. The prevalence of GERD patients with successive secondary peristalsis during slow air injection significantly increased after capsaicin infusion (P = 0.001). Repeated capsaicin infusion increased threshold volume of secondary peristalsis (P = 0.002) and reduced the frequency of secondary peristalsis (P = 0.02) during rapid air injection. CONCLUSION Acute esophageal exposure to capsaicin enhances heartburn sensation and promotes secondary peristalsis in gastroesophageal reflux disease, but repetitive capsaicin infusion reverses these effects. PMID:28018112

Influence of dorsiflexion shoes on neuromuscular fatigue of the plantar flexors after combined tapping-jumping exercises in volleyball players.

PubMed

Lapole, Thomas; Ahmaidi, Said; Gaillien, Benjamin; Leprêtre, Pierre-Marie

2013-07-01

Dorsiflexion shoes could be useful to increase jumping performance. The aim of the present study was to investigate the impact of wearing shoes inducing moderate dorsiflexion (2°) on neuromuscular fatigue induced by volleyball exercises involving multiple stretch-shortening cycles. Squat jump (SJ) and countermovement jump (CMJ) performance, and plantar flexors isometric voluntary and evoked contractile properties were assessed in 10 unfamiliarized trained volleyball players before and after a 10-minute intensive combined tapping-jumping volleyball exercise performed, in blinded randomized conditions, with neutral (0°) or moderate dorsiflexion (2°). No significant difference was observed on SJ performance in neutral and moderate dorsiflexion conditions. However, CMJ height was initially lower with 2° dorsiflexion compared with 0° (p < 0.05). Height in CMJ was increased after exercise with 2° dorsiflexion shoes and remained unchanged in neutral 0° condition. Combined tapping-jumping volleyball exercise also induced a significant decrease in maximal voluntary contraction (p < 0.001), peak-twitch torque (p = 0.009), contraction time (p < 0.001) and twitch relaxation rate (p = 0.001) values without any significant difference between neutral and dorsiflexion conditions. Voluntary activation level (p = 0.014) and rate of force development (p = 0.05) were also decreased in both conditions. In conclusion, acute moderate dorsiflexion had no effect on jumping performance and neuromuscular fatigue in unfamiliarized trained subjects and altered the elastic energy store in plyometric condition (CMJ). Future studies are necessary to investigate the chronic effect of moderate dorsiflexion on jumping performance and neuromuscular fatigue in trained volleyball players.

Overnight shift work: factors contributing to diagnostic discrepancies.

PubMed

Hanna, Tarek N; Loehfelm, Thomas; Khosa, Faisal; Rohatgi, Saurabh; Johnson, Jamlik-Omari

2016-02-01

The aims of the study are to identify factors contributing to preliminary interpretive discrepancies on overnight radiology resident shifts and apply this data in the context of known literature to draw parallels to attending overnight shift work schedules. Residents in one university-based training program provided preliminary interpretations of 18,488 overnight (11 pm–8 am) studies at a level 1 trauma center between July 1, 2013 and December 31, 2014. As part of their normal workflow and feedback, attendings scored the reports as major discrepancy, minor discrepancy, agree, and agree--good job. We retrospectively obtained the preliminary interpretation scores for each study. Total relative value units (RVUs) per shift were calculated as an indicator of overnight workload. The dataset was supplemented with information on trainee level, number of consecutive nights on night float, hour, modality, and per-shift RVU. The data were analyzed with proportional logistic regression and Fisher's exact test. There were 233 major discrepancies (1.26 %). Trainee level (senior vs. junior residents; 1.08 vs. 1.38 %; p < 0.05) and modality were significantly associated with performance. Increased workload affected more junior residents' performance, with R3 residents performing significantly worse on busier nights. Hour of the night was not significantly associated with performance, but there was a trend toward best performance at 2 am, with subsequent decreased accuracy throughout the remaining shift hours. Improved performance occurred after the first six night float shifts, presumably as residents acclimated to a night schedule. As overnight shift work schedules increase in popularity for residents and attendings, focused attention to factors impacting interpretative accuracy is warranted.

Effect of fuel properties on performance of a single aircraft turbojet combustor. [from coal and oil-shale derived syncrudes

NASA Technical Reports Server (NTRS)

Butze, H. F.; Ehlers, R. C.

1975-01-01

The performance of a single-can JT8D combustor was investigated with a number of fuels exhibiting wide variations in chemical composition and volatility. Performance parameters investigated were combustion efficiency, emissions of CO, unburned hydrocarbons and NOx, as well as liner temperatures and smoke. At the simulated idle condition no significant differences in performance were observed. At cruise, liner temperatures and smoke increased sharply with decreasing hydrogen content of the fuel. No significant differences were observed in the performance of an oil-shale derived JP-5 and a petroleum-based Jet A fuel except for emissions of NOx which were higher with the oil-shale JP-5. The difference is attributed to the higher concentration of fuel-bound nitrogen in the oil-shale JP-5.

Hemodynamic changes in the brachial artery induced by acupuncture stimulation on the lower limbs: a single-blind randomized controlled trial.

PubMed

Watanabe, Masashi; Takayama, Shin; Hirano, Atsushi; Seki, Takashi; Yaegashi, Nobuo

2012-01-01

Acupuncture is commonly performed at acupoints. No comparisons of quantitative physiological alterations in the brachial artery (BA) induced by the stimulation of different acupoints in the lower limbs have been performed in humans. Therefore, we investigated changes in blood flow volume (BFV) in the BA as an indicator of the physiological effects induced by stimulation at 3 points. Seventy-five healthy participants aged 33 ± 9 years (mean ± SD) were enrolled and randomly assigned to 3 groups; they received stimulation at 3 different points located on the lower limbs: ST36, LR3, and a non-acupoint. Stimulation was performed bilaterally with manual rotation of the needles. Using ultrasonography, BFV was measured continuously from rest to 180 seconds after stimulation. LR3 stimulation significantly increased BFV compared to that before needle insertion. Meanwhile, stimulation at ST36 and the non-acupoint significantly decreased BFV compared to that before needle insertion. Stimulation at LR3 elicited a significant increase in BFV compared to that at ST36 and the non-acupoint. The results suggest that the stimulation of different points on the lower limbs causes distinct physiological effects on BFV in the BA.

Batting cage performance of wood and nonwood youth baseball bats.

PubMed

Crisco, Joseph J; Rainbow, Michael J; Schwartz, Joel B; Wilcox, Bethany J

2014-04-01

The purpose of this study was to examine the batting cage performance of wood and nonwood baseball bats used at the youth level. Three wood and ten nonwood bats were swung by 22 male players (13 to 18 years old) in a batting cage equipped with a 3-dimensional motion capture (300 Hz) system. Batted ball speeds were compared using a one-way ANOVA and bat swing speeds were analyzed as a function of bat moment of inertia by linear regression. Batted ball speeds were significantly faster for three nonwood bat models (P<.001), significantly slower for one nonwood model, and not different for six nonwood bats when compared with wood bats. Bat impact speed significantly (P<.05) decreased with increasing bat moment of inertia for the 13-, 14-, and 15-year-old groups, but not for the other age groups. Ball-bat coefficients of restitution (BBCOR) for all nonwood were greater than for wood, but this factor alone did not correlate with bat performance. Our findings indicate that increases in BBCOR and swing speed were not associated with faster batted ball speeds for the bats studied whose moment of inertia was substantially less than that of a wood bat of similar length.

Combined Dextroamphetamine and Transcranial Direct Current Stimulation in Poststroke Aphasia.

PubMed

Keser, Zafer; Dehgan, Michelle Weber; Shadravan, Shaparak; Yozbatiran, Nuray; Maher, Lynn M; Francisco, Gerard E

2017-10-01

There is a growing need for various effective adjunctive treatment options for speech recovery after stroke. A pharmacological agent combined with noninvasive brain stimulation has not been previously reported for poststroke aphasia recovery. In this "proof of concept" study, we aimed to test the safety of a combined intervention consisting of dextroamphetamine, transcranial direct current stimulation, and speech and language therapy in subjects with nonfluent aphasia. Ten subjects with chronic nonfluent aphasia underwent two experiments where they received dextroamphetamine or placebo along with transcranial direct current stimulation and speech and language therapy on two separate days. The Western Aphasia Battery-Revised was used to monitor changes in speech performance. No serious adverse events were observed. There was no significant increase in blood pressure with amphetamine or deterioration in speech and language performance. Western Aphasia Battery-Revised aphasia quotient and language quotient showed a statistically significant increase in the active experiment. Comparison of proportional changes of aphasia quotient and language quotient in active experiment with those in placebo experiment showed significant difference. We showed that the triple combination therapy is safe and implementable and seems to induce positive changes in speech and language performance in the patients with chronic nonfluent aphasia due to stroke.

Study on development of accessory sex glands in prepubertal kids using two-dimensional ultrasonography.

PubMed

Kumari, Sonu; Luthra, R A; Chandolia, R K; Kumar, Sandeep; Kumar, Parveen; Devender; Kumar, Ankit; Bishnoi, Nidhi; Bishnoi, Sunil

2016-04-01

The present study was undertaken to study growth pattern of accessory sex glands in prepubertal kids from 2 weeks to 6 months of age using two-dimensional ultrasonography. The study was conducted on six Beetal kids. The scanning of accessory sex glands was done in standing position using rectal probe and measurements were recorded. Data collected were statistically analyzed using one-way ANOVA followed by Duncan multiple range test was performed using the SPSS (16.0) system for windows. With the advancement of age all the dimensions of glands increased. Both the lobes of prostate gland showed an increase in width with advancement of age. Width of prostate above the urethra (W1) showed a significant increase at 2, 10, and 20 weeks of age, whereas non-significant increase from 2 to 8, 10 to 19, and 20 to 24 weeks of age was recorded. Width of prostate below the urethra (W2) showed a significant increase at 20 weeks of age, whereas non-significant increase was recorded during rest of period of growth. Left and right bulbourethral gland showed a similar pattern of growth with the advancement of age. The circumference dimensions increased significantly at 2, 16, 20, and 21 weeks of age for both glands. The increase was non-significant from 4 to 14, 16 to 19, and 20 to 23 weeks of age. The same pattern was observed for left and right seminal vesicular gland. Significant growth in three accessory sex glands in prepubertal kids was not observed at the same age. The trend observed was that the prostate was the first gland to show significant growth at 10 weeks of age followed by a significant increase in seminal vesicles and bulbourethral gland at 14 and 16 weeks of age, respectively.

Active dehydration impairs upper and lower body anaerobic muscular power.

PubMed

Jones, Leon C; Cleary, Michelle A; Lopez, Rebecca M; Zuri, Ron E; Lopez, Richard

2008-03-01

We examined the effects of active dehydration by exercise in a hot, humid environment on anaerobic muscular power using a test-retest (euhydrated and dehydrated) design. Seven subjects (age, 27.1 +/- 4.6 years; mass, 86.4 +/- 9.5 kg) performed upper and lower body Wingate anaerobic tests prior to and after a 1.5-hour recovery from a heat stress trial of treadmill exercise in a hot, humid environment (33.1 +/- 3.1C = 55.1 +/- 8.9% relative humidity) until a 3.1 +/- 0.3% body mass loss was achieved. Dehydration was confirmed by a significant body mass loss (P < 0.001), urine color increase (P = 0.004), and urine specific gravity increase (P = 0.041). Motivation ratings were not significantly different (P = 0.059), and fatigue severity was significantly (P = 0.009) increased 70% in the dehydrated compared to the euhydrated condition. Compared to the euhydrated condition, the dehydrated condition mean power was significantly (P = 0.014) decreased 7.17% in the upper body and 19.20% in the lower body. Compared to the euhydrated condition, the dehydrated condition peak power was significantly (P = 0.013) decreased 14.48% in the upper body and 18.36% in the lower body. No significant differences between the euhydrated and dehydrated conditions were found for decrease in power output (P = 0.219, power = 0.213). Our findings suggest that dehydration of 2.9% body mass decreases the ability to generate upper and lower body anaerobic power. Coaches and athletes must understand that sports performance requiring anaerobic strength and power can be impaired by inadequate hydration and may contribute to increased susceptibility to musculoskeletal injury.

Prospective Memory Deficits Are Associated With Poorer Everyday Functioning in Parkinson’s Disease

PubMed Central

Pirogovsky, Eva; Woods, Steven Paul; Filoteo, J. Vincent; Gilbert, Paul E.

2013-01-01

Although individuals with Parkinson’s disease (PD) evidence moderate deficits in prospective memory (PM), it is not known whether PM deficits confer an increased risk of poorer everyday functioning. In the current study, 33 individuals with PD and 26 demographically similar normal controls (NC) were administered performance-based and self-report measures of PM and everyday functioning, including medication and financial management. As compared to NC, PD participants demonstrated significantly lower scores on performance-based measures of PM and financial capacity, worse performance at a trend level on performance-based medication management and endorsed significantly greater self-reported declines in PM and instrumental activities of daily living (iADLs). In the PD sample, the laboratory measure of PM significantly correlated with performance-based measures of financial capacity and medication management and a self-report measure of medication management. Self-reported PM failures significantly correlated with perceived declines in iADLs, worse medication management, and poorer health-related quality of life. Although future studies are needed to examine the incremental ecological validity of PM in PD, findings from this study extend prior research by providing preliminary evidence that PM impairment may play a significant role in a range of critical everyday functions in PD. PMID:22846463

Body composition and physical performance during a National Collegiate Athletic Association Division I men's soccer season.

PubMed

Silvestre, Ricardo; Kraemer, William J; West, Chris; Judelson, Daniel A; Spiering, Barry A; Vingren, Jakob L; Hatfield, Disa L; Anderson, Jeffrey M; Maresh, Carl M

2006-11-01

The purpose of this study was to examine changes in body composition (BC) and physical performance tests (PT) resulting from a competitive season in soccer. Twenty-five male collegiate players (age = 19.9 +/- 1.3 years; height = 177.6 +/- 6.4 cm; body mass = 77.6 +/- 8.6 kg, and percentage body fat = 12.8 +/- 5.2%) were tested before (PRE) and after (POST) the 2003-2004 National Collegiate Athletic Association season. The following tests were performed: BC (anthropometric and dual energy x-ray absorptiometry measurements), vertical jump (VJ), 9.1-m (9 m) and 36.5-m (36 m) sprint, lower-body power (LP), total body power (TP), and cardiorespiratory endurance (VO(2)max). Training was divided into soccer-specific training: field warm-up drills, practices, games, and additional conditioning sessions. A daily, unplanned, nonlinear periodization model was used to assign session volume and intensity for strength sessions (total repetitions < or =96 and workload was > or =80% of 1 repetition maximum). For the entire team, body mass significantly increased by 1.5 +/- 0.4 kg from PRE to POST due to a significant increase in total lean tissue (0.9 +/- 0.2 kg). Regionally, lean tissue mass significantly increased in the legs (0.4 +/- 0.0 kg) and trunk (0.3 +/- 0.1 kg). Physical performance variables were very similar for the entire team at PRE and POST; VJ (cm) = 61.9 +/- 7.1 PRE vs. 63.3 +/- 8.0 POST, 9.1-m (s) = 1.7 +/- 0.1 PRE and POST, 36.5-m (s) = 5.0 +/- 0.2 PRE and POST, predicted VO(2)max (ml.kg.min(-1))= 59.8 +/- 3.3 PRE vs. 60.9 +/- 3.4 POST. The only significant improvements across the season were for TP (17.3%) and for LP (10.7%). In conclusion, soccer athletes who begin a season with a high level of fitness can maintain, and in some cases improve, body composition and physical performance from before to after a competitive season. A correct combination of soccer-specific practices and strength and conditioning programs can maintain and develop physical performance, allowing a soccer athlete to perform optimally throughout pre-, in-, and postseason play.