Solar powered automobile automation for heatstroke prevention
NASA Astrophysics Data System (ADS)
Singh, Navtej Swaroop; Sharma, Ishan; Jangid, Santosh
2016-03-01
Heatstroke inside a car has been critical problem in every part of the world. Non-exertional heat stroke results from exposure to a high environmental temperature. Exertional heat stroke happens from strenuous exercise. This paper presents a solution for this fatal problem and proposes an embedded solution, which is cost effective and shows the feasibility in implementation. The proposed system consists of information sharing platform, interfacing of sensors, Global System Mobile (GSM), real time monitoring system and the system is powered by the solar panel. The system has been simulated and tested with experimental setup.
Hibi, N; Fujinaga, H; Ishii, K
1996-01-01
Work and power outputs during short-term, maximal exertion on a friction loaded cycle ergometer are usually calculated from the friction force applied to the flywheel. The inertia of the flywheel is sometimes taken into consideration, but the effects of internal resistances and other factors have been ignored. The purpose of this study was to estimate their effects by comparing work or power output determined from the force exerted on the pedals (pedalling force) with work or power output determined from the friction force and the moment of inertia of the rotational parts. A group of 22 male college students accelerated a cycle ergometer as rapidly as possible for 3 s. The total work output determined from the pedalling force (TWp) was significantly greater than that calculated from the friction force and the moment of inertia (TWf). Power output determined from the pedalling force during each pedal stroke (SPp) was also significantly greater than that calculated from the friction force and the moment of inertia. Percentage difference (% diff), defined by % diff = ¿(TWp - TWf)/TWf¿ x 100, ranged from 16.8% to 49.3% with a mean value of 30.8 (SD 9.1)%. It was observed that % diff values were higher in subjects with greater TWp or greater maximal SPp. These results would indicate that internal resistances and other factors, such as the deformation of the chain and the vibrations of the entire system, may have significant effects on the measurements of work and power outputs. The effects appear to depend on the magnitudes of pedalling force and pedal velocity.
Effects of High-Speed Power Training on Muscle Performance and Braking Speed in Older Adults
Sayers, Stephen P.; Gibson, Kyle
2012-01-01
We examined whether high-speed power training (HSPT) improved muscle performance and braking speed using a driving simulator. 72 older adults (22 m, 50 f; age = 70.6 ± 7.3 yrs) were randomized to HSPT at 40% one-repetition maximum (1RM) (HSPT: n = 25; 3 sets of 12–14 repetitions), slow-speed strength training at 80%1RM (SSST: n = 25; 3 sets of 8–10 repetitions), or control (CON: n = 22; stretching) 3 times/week for 12 weeks. Leg press and knee extension peak power, peak power velocity, peak power force/torque, and braking speed were obtained at baseline and 12 weeks. HSPT increased peak power and peak power velocity across a range of external resistances (40–90% 1RM; P < 0.05) and improved braking speed (P < 0.05). Work was similar between groups, but perceived exertion was lower in HSPT (P < 0.05). Thus, the less strenuous HSPT exerted a broader training effect and improved braking speed compared to SSST. PMID:22500229
Tiggemann, Carlos Leandro; Dias, Caroline Pieta; Radaelli, Regis; Massa, Jéssica Cassales; Bortoluzzi, Rafael; Schoenell, Maira Cristina Wolf; Noll, Matias; Alberton, Cristine Lima; Kruel, Luiz Fernando Martins
2016-04-01
The present study compared the effects of 12 weeks of traditional resistance training and power training using rated perceived exertion (RPE) to determine training intensity on improvements in strength, muscle power, and ability to perform functional task in older women. Thirty healthy elderly women (60-75 years) were randomly assigned to traditional resistance training group (TRT; n = 15) or power training group (PT; n = 15). Participants trained twice a week for 12 weeks using six exercises. The training protocol was designed to ascertain that participants exercised at an RPE of 13-18 (on a 6-20 scale). Maximal dynamic strength, muscle power, and functional performance of lower limb muscles were assessed. Maximal dynamic strength muscle strength leg press (≈58 %) and knee extension (≈20 %) increased significantly (p < 0.001) and similarly in both groups after training. Muscle power also increased with training (≈27 %; p < 0.05), with no difference between groups. Both groups also improved their functional performance after training period (≈13 %; p < 0.001), with no difference between groups. The present study showed that TRT and PT using RPE scale to control intensity were significantly and similarly effective in improving maximal strength, muscle power, and functional performance of lower limbs in elderly women.
Dynamics of Perceived Exertion in Constant-Power Cycling: Time- and Workload-Dependent Thresholds
ERIC Educational Resources Information Center
Balagué, Natàlia; Hristovski, Robert; García, Sergi; Aguirre, Cecilia; Vázquez, Pablo; Razon, Selen; Tenenbaum, Gershon
2015-01-01
Purpose: The purpose of this study was to test the dynamics of perceived exertion shifts (PES) as a function of time and workload during constant-power cycling. Method: Fifty-two participants assigned to 4 groups performed a cycling task at 4 different constant workloads corresponding to their individual rates of perceived exertion (RPEs = 13, 15,…
Nelson, Mackenzie E.; Krimmel, Samuel R.; Georgiou, Polymnia; Gould, Todd D.
2017-01-01
Abstract New antidepressant pharmacotherapies that provide rapid relief of depressive symptoms are needed. The NMDA receptor antagonist ketamine exerts rapid antidepressant actions in depressed patients but also side effects that complicate its clinical utility. Ketamine promotes excitatory synaptic strength, likely by producing high-frequency correlated activity in mood-relevant regions of the forebrain. Negative allosteric modulators of GABA-A receptors containing α5 subunits (α5 GABA-NAMs) should also promote high-frequency correlated electroencephalogram (EEG) activity and should therefore exert rapid antidepressant responses. Because α5 subunits display a restricted expression in the forebrain, we predicted that α5 GABA-NAMs would produce activation of principle neurons but exert fewer side effects than ketamine. We tested this hypothesis in male mice and observed that the α5 GABA-NAM MRK-016 exerted an antidepressant-like response in the forced swim test at 1 and 24 h after administration and an anti-anhedonic response after chronic stress in the female urine sniffing test (FUST). Like ketamine, MRK-016 produced a transient increase in EEG γ power, and both the increase in γ power and its antidepressant effects in the forced swim test were blocked by prior administration of the AMPA-type glutamate receptor antagonist 2,3-dioxo-6-nitro-1,2,3,4-tetrahydrobenzo[f]quinoxaline-7-sulfonamide (NBQX). Unlike ketamine, however, MRK-016 produced no impairment of rota-rod performance, no reduction of prepulse inhibition (PPI), no conditioned-place preference (CPP), and no change in locomotion. α5 GABA-NAMs, thus reproduce the rapid antidepressant-like actions of ketamine, perhaps via an AMPA receptor (AMPAR)-dependent increase in coherent neuronal activity, but display fewer potential negative side effects. These compounds thus demonstrate promise as clinically useful fast-acting antidepressants. PMID:28275719
Jensen's Inequality Predicts Effects of Environmental Variation
Jonathan J. Ruel; Matthew P. Ayres
1999-01-01
Many biologists now recognize that environmental variance can exert important effects on patterns and processes in nature that are independent of average conditions. Jenson's inequality is a mathematical proof that is seldom mentioned in the ecological literature but which provides a powerful tool for predicting some direct effects of environmental variance in...
Determination of the myosin step size from mechanical and kinetic data.
Pate, E; White, H; Cooke, R
1993-01-01
During muscle contraction, work is generated when a myosin cross-bridge attaches to an actin filament and exerts a force on it through some power-stroke distance, h. At the end of this power stroke, attached myosin heads are carried into regions where they exert a negative force on the actin filament (the drag stroke) and where they are released rapidly from actin by ATP binding. Although the length of the power stroke remains controversial, average distance traversed in the drag-stroke region can be determined when one knows both rate of cross-bridge dissociation and filament-sliding velocity. At maximum contraction velocity, the average force exerted in the drag stroke must balance that exerted in the power stroke. We discuss here a simple model of cross-bridge interaction that allows one to calculate the force exerted in the drag stroke and to relate this to the power-stroke distance h traversed by cross-bridges in the positive-force region. Both the rate at which myosin can be dissociated from actin and the velocity at which an actin filament can be translated have been measured for a series of myosin isozymes and for different substrates, producing a wide range of values for each. Nonetheless, we show here that the rate of myosin dissociation from actin correlates well with the velocity of filament sliding, providing support for the simple model presented and suggesting that the power stroke is approximately 10 nm in length. PMID:8460156
Hamer, Mark; Boutcher, Yati N; Boutcher, Stephen H
2005-12-01
This study examined differentiated rating of perceived exertion (RPE), heart rate, and heart-rate variability during light cycle ergometry exercise at two different pedal rates. 30 healthy men (22.6 +/- 0.9 yr.) were recruited from a student population and completed a continuous 20-min. cycle ergometry exercise protocol, consisting of a 4-min. warm-up (60 rev./min., 30 Watts), followed by four bouts of 4 min. at different combinations of pedal rate (40 or 80 rev./min.) and power output (40 or 80 Watts). The order of the four combinations was counterbalanced across participants. Heart rate was measured using a polar heart-rate monitor, and parasympathetic balance was assessed through time series analysis of heart-rate variability. Measures were compared using a 2 (pedal rate) x 2 (power output) repeated-measures analysis of variance. RPE was significantly greater (p<.05) at 80 versus 40 rev./min. at 40 W. For both power outputs heart rate was significantly increased, and the high frequency component of heart-rate variability was significantly reduced at 80 compared with 40 rev./min. These findings indicate the RPE was greater at higher than at lower pedalling rates for a light absolute power output which contrasts with previous findings based on use of higher power output. Also, pedal rate had a significant effect on heart rate and heart-rate variability at constant power output.
ERIC Educational Resources Information Center
Mittan, Robert J.
2010-01-01
In the last article the author discussed the powerful effect epilepsy has on the social functioning of the classroom and how this impact can affect learning difficulties in the student. Epilepsy also exerts a powerful influence upon the teacher, depending how educated that teacher is and any fears about seizures the teacher may harbor. Fortunately…
Effect of active warm-up duration on morning short-term maximal performance during Ramadan.
Baklouti, Hana; Chtourou, Hamdi; Aloui, Asma; Chaouachi, Anis; Souissi, Nizar
2015-01-01
Purpose To examine the effect of active warm-up duration on short-term maximal performance assessed during Ramadan in the morning. Methods Twelve healthy active men performed four Wingate tests for measurement of peak power and mean power before and during Ramadan at 09:00 a.m. The tests were performed on separate days, after either a 5-min or a 15-min warm-up. The warm-up consisted in pedaling at 50% of the power output obtained at the last stage of a submaximal multistage cycling test. Oral temperature was measured at rest and after warming-up. Furthermore, ratings of perceived exertion were obtained immediately after the Wingate test. Results Oral temperature was higher after the 15-min warm-up than the 5-min warm-up throughout the study. Moreover, peak power and mean power were higher after the 15-min warm-up than the 5-min warm-up before Ramadan. However, during Ramadan, there was no significant difference between the two warm-up durations. In addition, ratings of perceived exertion were higher after the 15-min warm-up than the 5-min warm-up only during Ramadan. Conclusions There is no need to prolong the warm-up period before short-term maximal exercise performed during Ramadan in the morning.
Effect of active warm-up duration on morning short-term maximal performance during Ramadan.
Baklouti, Hana; Chtourou, Hamdi; Aloui, Asma; Chaouachi, Anis; Souissi, Nizar
2015-01-01
To examine the effect of active warm-up duration on short-term maximal performance assessed during Ramadan in the morning. Twelve healthy active men performed four Wingate tests for measurement of peak power and mean power before and during Ramadan at 09:00 a.m. The tests were performed on separate days, after either a 5-min or a 15-min warm-up. The warm-up consisted in pedaling at 50% of the power output obtained at the last stage of a submaximal multistage cycling test. Oral temperature was measured at rest and after warming-up. Furthermore, ratings of perceived exertion were obtained immediately after the Wingate test. Oral temperature was higher after the 15-min warm-up than the 5-min warm-up throughout the study. Moreover, peak power and mean power were higher after the 15-min warm-up than the 5-min warm-up before Ramadan. However, during Ramadan, there was no significant difference between the two warm-up durations. In addition, ratings of perceived exertion were higher after the 15-min warm-up than the 5-min warm-up only during Ramadan. There is no need to prolong the warm-up period before short-term maximal exercise performed during Ramadan in the morning.
Effect of active warm-up duration on morning short-term maximal performance during Ramadan
Baklouti, Hana; Chtourou, Hamdi; Aloui, Asma; Chaouachi, Anis; Souissi, Nizar
2015-01-01
Purpose To examine the effect of active warm-up duration on short-term maximal performance assessed during Ramadan in the morning. Methods Twelve healthy active men performed four Wingate tests for measurement of peak power and mean power before and during Ramadan at 09:00 a.m. The tests were performed on separate days, after either a 5-min or a 15-min warm-up. The warm-up consisted in pedaling at 50% of the power output obtained at the last stage of a submaximal multistage cycling test. Oral temperature was measured at rest and after warming-up. Furthermore, ratings of perceived exertion were obtained immediately after the Wingate test. Results Oral temperature was higher after the 15-min warm-up than the 5-min warm-up throughout the study. Moreover, peak power and mean power were higher after the 15-min warm-up than the 5-min warm-up before Ramadan. However, during Ramadan, there was no significant difference between the two warm-up durations. In addition, ratings of perceived exertion were higher after the 15-min warm-up than the 5-min warm-up only during Ramadan. Conclusions There is no need to prolong the warm-up period before short-term maximal exercise performed during Ramadan in the morning. PMID:25676856
NASA Astrophysics Data System (ADS)
Vaskovskaya, T. A.
2014-12-01
This paper offers a new approach to the analysis of price signals from the wholesale electricity and capacity market that is based on the analysis of the influence exerted by input data used in the problem of optimization of the power system operating conditions, namely: parameters of a power grid and power-receiving equipment that might vary under the effect of control devices. It is shown that it would be possible to control nonregulated prices for electricity in the wholesale electricity market by varying the parameters of control devices and energy-receiving equipment. An increase in the effectiveness of power transmission and the cost-effective use of fuel-and-energy resources (energy saving) can become an additional effect of controlling the nonregulated prices.
Making the Soldier Decisive on Future Battlefields
2013-01-01
mostly real. They are also affected by physical stressors ranging from the exertion while carrying a load and extreme temperatures to the effects ...Military Effects , 36 Lethality, 36 Stability and Humanitarian Effects , 38 Maneuverability, 40 Sustainability, 41 Power and Energy, 41...Integration Priorities, 100 Balancing TSU Maneuverability, Military Effects , and Survivability, 105 Soldiers Carry Too Much to Move Quickly, Act
Exertion Testing in Youth with Mild Traumatic Brain Injury/Concussion.
Dematteo, Carol; Volterman, Kimberly A; Breithaupt, Peter G; Claridge, Everett A; Adamich, John; Timmons, Brian W
2015-11-01
The decision regarding return to activity (RTA) after mild traumatic brain injuries/concussion is one of the most difficult and controversial areas in concussion management, particularly for youth. This study investigated how youth with postconcussion syndrome (PCS) are affected by exertion and whether standardized exertion testing using the McMaster All-Out Progressive Continuous Cycling Test can contribute to clinical decision making for safe RTA. Fifty-four youth (8.5-18.3 yr) with a previously confirmed concussion participated in the study. Each participant performed exertion testing on a cycle ergometer and completed a Postconcussion Symptom scale at the following time points: before exertion (baseline), 5 and 30 min, and 24 h after exertion. A modified Postconcussion Symptom scale was administered at 2-min intervals during exertion. Participants had a mean ± SD symptom duration of 6.3 ± 6.9 months after the most recent concussive injury, with a median of 4.1 months (range, 0.7-35 months). Sixty-three percent of participants had symptoms during exertion testing. Symptom profile (number and severity) significantly affected perception of exertion at 50% peak mechanical power. During acute assessment of symptoms (30-min after exertion), headache (P = 0.39), nausea (P = 0.63), and dizziness (P = 0.35) did not change. However, both the number and severity of symptoms significantly improved over 24 h, with 56.8% of youth showing improvements. The time from the most recent injury had a significant effect on the symptom score at baseline, 30 min after exertion, and 24 h after exertion. Exertion testing has an important role in the evaluation of symptoms and readiness to RTA, particularly in youth who are slow to recover. Overall, controlled exertion seemed to lesson symptoms for most youth.
Wu, Cheng-Hua; Mao, Hui-Fen; Hu, Jwu-Sheng; Wang, Ting-Yun; Tsai, Yi-Jeng; Hsu, Wei-Li
2018-03-05
Powered exoskeleton can improve the mobility for people with movement deficits by providing mechanical support and facilitate the gait training. This pilot study evaluated the effect of gait training using a newly developed powered lower limb exoskeleton robot for individuals with complete spinal cord injury (SCI). Two participants with a complete SCI were recruited for this clinical study. The powered exoskeleton gait training was 8 weeks, 1 h per session, and 2 sessions per week. The evaluation was performed before and after the training for (1) the time taken by the user to don and doff the powered exoskeleton independently, (2) the level of exertion perceived by participants while using the powered exoskeleton, and (3) the mobility performance included the timed up-and-go test, 10-m walk test, and 6-min walk test with the powered exoskeleton. The safety of the powered exoskeleton was evaluated on the basis of injury reports and the incidence of falls or imbalance while using the device. The results indicated that the participants were donning and doffing the powered lower limb exoskeleton robot independently with a lower level of exertion and walked faster and farther without any injury or fall incidence when using the powered exoskeleton than when using a knee-ankle-foot orthosis. Bone mineral densities was also increased after the gait training. No adverse effects, such as skin abrasions, or discomfort were reported while using the powered exoskeleton. The findings demonstrated that individuals with complete SCI used the powered lower limb exoskeleton robot independently without any assistance after 8 weeks of powered exoskeleton gait training. Trial registration: National Taiwan University Hospital. 201210051RIB . Name of registry: Hui-Fen Mao. URL of registry: Not available. Date of registration: December 12th, 2012. Date of enrolment of the first participant to the trial: January 3rd, 2013.
Antioxidative effects of cinnamomi cortex: A potential role of iNOS and COX-II
Chung, Jin-Won; Kim, Jeong-Jun; Kim, Sung-Jin
2011-01-01
Background: Cinnamomi cortex has wide varieties of pharmacological actions such as anti-inflammatory action, anti-platelet aggregation, and improving blood circulation. In this study, we tested to determine whether the Cinnamomi cortex extract has antioxidant activities. Materials and Methods: Antioxidative actions were explored by measuring free radical scavenging activity, NO levels, and reducing power. The mechanism of antioxidative action of Cinnamomi cortex was determined by measuring iNOS and COX-II expression in lipopolysaccharide (LPS) stimulated Raw cells. Results: Seventy percent methanolic extract of Cinnamomi cortex exerted significant 1,1-diphenyl--2--picrylhydrazyl (DPPH) free radicals and NO scavenging activities in a dose-dependent manner. More strikingly, the Cinnamomi cortex extract exerted dramatic reducing power activity (13-fold over control). Production of iNOS induced by LPS was significantly inhibited by the Cinnamomi cortex extract, suggesting that it inhibits NO production by suppressing iNOS expression. Additionally, COX-2 induced by LPS was dramatically inhibited by the Cinnamomi cortex extract. Conclusion: These results suggest that 70% methanolic extract of Cinnamomi cortex exerts significant antioxidant activity via inhibiting iNOS and COX-II induction. PMID:22262934
ERIC Educational Resources Information Center
Solomon, Bertina Loutrice
2011-01-01
This study researched whether family members and significant others influence a woman's decision to obtain an abortion. Influence is defined by Merriam-Webster (2011) as the power or capacity of causing an effect in indirect or intangible ways; power exerted over the minds or behaviors of others. The theoretical framework that will be used in…
Short-Term Effects of Rolling Massage on Energy Cost of Running and Power of the Lower Limbs.
Giovanelli, Nicola; Vaccari, Filippo; Floreani, Mirco; Rejc, Enrico; Copetti, Jasmine; Garra, Marco; Biasutti, Lea; Lazzer, Stefano
2018-05-10
Self-myofascial release (SMFR) is a type of self-massage that is becoming popular among athletes. However, SMFR effects on running performance have not been investigated yet. The aim of the present study was to evaluate the effects of SMFR on cost of running (Cr). In addition, we evaluated the effects of SMFR on lower limbs muscle power. The measurement of Cr and lower limb muscle power during squat jump (SJ) and counter movement jump (CMJ) were performed before (PRE), immediately after (POST) and 3hours after (POST 3h) a SMFR protocol (experimental condition). In the "control condition" testing session, the same measurements were performed without undergoing the SMFR protocol. Experimental and control conditions were tested in a randomized order. Cr at POST trended to increase as compared to PRE (+6.2±8.3%, p=0.052), while at POST 3h Cr was restored to PRE values (+0.28±9.5%, p=0.950). In the experimental condition, no significant "Time" effect was observed for maximal power exerted during SJ. On the other hand, maximal power exerted during CMJ at POST and POST 3h was significantly higher than that observed at PRE (+7.9±6.3%, p=0.002; and +10.0±8.7%, p=0.004, respectively). The rate of force development measured during CMJ also increased after SMFR, reaching statistical significance at 200 ms from force onset at POST 3h (+38.9%, p=0.024). an acute use of foam roller for SMFR performed immediately prior to running may negatively affect the endurance running performance, while its use should be added before explosive motor performances that include stretch-shortening cycles.
Behavioral Confirmation in Social Interaction: From Social Perception to Social Reality
ERIC Educational Resources Information Center
Snyder, Mark; Swann, William B., Jr.
1978-01-01
Of what importance are our impressions and perceptions of others? This empirical investigation suggests that social perceptions can and do exert powerful channeling effects on subsequent social interaction such that actual behavioral confirmation of these beliefs is produced. Outlines a theoretical account of the processes believed to underlie…
Phosphate and acidosis act synergistically to depress peak power in rat muscle fibers.
Nelson, Cassandra R; Debold, Edward P; Fitts, Robert H
2014-11-15
Skeletal muscle fatigue is characterized by the buildup of H(+) and inorganic phosphate (Pi), metabolites that are thought to cause fatigue by inhibiting muscle force, velocity, and power. While the individual effects of elevated H(+) or Pi have been well characterized, the effects of simultaneously elevating the ions, as occurs during fatigue in vivo, are still poorly understood. To address this, we exposed slow and fast rat skinned muscle fibers to fatiguing levels of H(+) (pH 6.2) and Pi (30 mM) and determined the effects on contractile properties. At 30°C, elevated Pi and low pH depressed maximal shortening velocity (Vmax) by 15% (4.23 to 3.58 fl/s) in slow and 31% (6.24 vs. 4.55 fl/s) in fast fibers, values similar to depressions from low pH alone. Maximal isometric force dropped by 36% in slow (148 to 94 kN/m(2)) and 46% in fast fibers (148 to 80 kN/m(2)), declines substantially larger than what either ion exerted individually. The strong effect on force combined with the significant effect on velocity caused peak power to decline by over 60% in both fiber types. Force-stiffness ratios significantly decreased with pH 6.2 + 30 mM Pi in both fiber types, suggesting these ions reduced force by decreasing the force per bridge and/or increasing the number of low-force bridges. The data indicate the collective effects of elevating H(+) and Pi on maximal isometric force and peak power are stronger than what either ion exerts individually and suggest the ions act synergistically to reduce muscle function during fatigue. Copyright © 2014 the American Physiological Society.
Schmidt, Barbara; Kanis, Hannah; Holroyd, Clay B; Miltner, Wolfgang H R; Hewig, Johannes
2018-06-20
In this study, we address the effect of anxiety measured with the State-Trait Anxiety Inventory (STAI) on EEG and risk decisions. We selected 20 high and 20 low anxious participants based on their STAI trait scores in the upper or lower quartile of the norm distribution and implemented a risk game developed in our laboratory. We investigate if high anxious individuals exert more cognitive control, reflected in higher frontal midline theta (FMT) power when they make a risky decision, and if they act less risky compared to low anxious individuals. Participants played a risk game while we recorded their brain responses via EEG. High anxious participants played less risky compared to low anxious participants. Further, high anxious participants showed higher FMT power immediately before they chose one of two risk options, suggesting higher cognitive control during the decision time compared to low anxious participants. Via a mediation analysis, we show that the effect of anxiety on risk behavior is fully mediated by FMT power. Further, questionnaire responses revealed that high anxious participants rated risk situations as riskier compared to low anxious participants. We conclude that anxious individuals perceive risky situations as riskier and thus exert more cognitive control during their risk choices, reflected in higher FMT power, which leads to less risky decisions. © 2018 Society for Psychophysiological Research.
Optimizing Controlling-Value-Based Power Gating with Gate Count and Switching Activity
NASA Astrophysics Data System (ADS)
Chen, Lei; Kimura, Shinji
In this paper, a new heuristic algorithm is proposed to optimize the power domain clustering in controlling-value-based (CV-based) power gating technology. In this algorithm, both the switching activity of sleep signals (p) and the overall numbers of sleep gates (gate count, N) are considered, and the sum of the product of p and N is optimized. The algorithm effectively exerts the total power reduction obtained from the CV-based power gating. Even when the maximum depth is kept to be the same, the proposed algorithm can still achieve power reduction approximately 10% more than that of the prior algorithms. Furthermore, detailed comparison between the proposed heuristic algorithm and other possible heuristic algorithms are also presented. HSPICE simulation results show that over 26% of total power reduction can be obtained by using the new heuristic algorithm. In addition, the effect of dynamic power reduction through the CV-based power gating method and the delay overhead caused by the switching of sleep transistors are also shown in this paper.
The Role of Motivation, Glucose and Self-Control in the Antisaccade Task
Kelly, Claire L.; Sünram-Lea, Sandra I.; Crawford, Trevor J.
2015-01-01
Research shows that self-control is resource limited and there is a gradual weakening in consecutive self-control task performance akin to muscle fatigue. A body of evidence suggests that the resource is glucose and consuming glucose reduces this effect. This study examined the effect of glucose on performance in the antisaccade task - which requires self-control through generating a voluntary eye movement away from a target - following self-control exertion in the Stroop task. The effects of motivation and individual differences in self-control were also explored. In a double-blind design, 67 young healthy adults received a 25g glucose or inert placebo drink. Glucose did not enhance antisaccade performance following self-control exertion in the Stroop task. Motivation however, predicted performance on the antisaccade task; more specifically high motivation ameliorated performance decrements observed after initial self-control exertion. In addition, individuals with high levels of self-control performed better on certain aspects of the antisaccade task after administration of a glucose drink. The results of this study suggest that the antisaccade task might be a powerful paradigm, which could be used as a more objective measure of self-control. Moreover, the results indicate that level of motivation and individual differences in self-control should be taken into account when investigating deficiencies in self-control following prior exertion. PMID:25826334
Salient Multiculturalism Enhances Minority Group Members' Feelings of Power.
Vorauer, Jacquie D; Quesnel, Matthew S
2017-02-01
The present research examined how messages advocating different intergroup ideologies affect outcomes relevant to minority group members' ability to exert power in exchanges with dominant group members. We expected that salient multiculturalism would have positive implications for minority group members' feelings of power by virtue of highlighting essential contributions they make to society, and that no such empowering effect would be evident for them in connection with alternative ideologies such as color-blindness or for dominant group members. Results across four studies involving different participant populations, operationalizations of ideology, ethnic minority groups, and experimental settings were consistent with these hypotheses and further indicated that the effects of salient multiculturalism on feelings of power had downstream implications for expectations of control in an ostensibly upcoming intergroup interaction and general goal-directed cognition.
The Play of Risk, Affect, and the Enterprising Self in a Fourth-Grade Classroom
ERIC Educational Resources Information Center
Bialostok, Steven; Kamberelis, George
2012-01-01
As a predominant discourse of the early twenty-first century, the new capitalism (and its companion cultural system, neoliberalism) privilege flexibility, risk, emotional intelligence, and the enterprising self. New capitalist discourses exert powerful and pervasive effects across all dimensions of human experience and activity from personal…
Tibana, Ramires A; Vieira, Denis C L; Tajra, Vitor; Bottaro, Martim; de Salles, Belmiro F; Willardson, Jeffrey M; Prestes, Jonato
2013-12-01
This study compared two different rest intervals (RI) between sets of resistance exercise. Ten resistance-trained men (M age = 24.3, SD = 3.5 yr.; M weigh t= 80.0 kg, SD = 15.3; M height = 1.75 m, SD = 0.04) performed five sets of Smith machine bench presses at 60% of one repetition maximum, either with 1.5 min. or 3 min. RI between sets. Their repetition performance, total training volume, velocity, fatigue, rating of perceived exertion, and muscular power were measured. All of these measures indicated that performance was significantly better and fatigue was significantly lower in the 3 min. RI as compared with the 1.5 min. RI, except the rating of perceived exertion which did not show a significant difference. A longer RI between sets promotes superior performance for the bench press.
Power production by Olympic weightlifters.
Garhammer, J
1980-01-01
A new procedure was developed for calculating power production during Olympic lifting movements and comparisons were made with a method previously used. The power output of seven superior lifters was determined during selected phases of the snatch, clean, and jerk, from films taken at the 1975 U.S. National Championships. The values obtained depended on the following variables: vertical change in the bar's mechanical energy from the beginning of a force exertion phase until maximum vertical bar velocity was achieved; work done by the athlete in producing horizontal bar movement; and work done in raising the body's center of gravity. Results showed the expected increase in power with increased bodyweight for a given movement. Values for the jerk drive ranged from 2140 watts in the 56 kg class to 4786 watts for a 110 kg lifter. Heavier lifters exceeded published maximal estimates for human power output during brief exertions. More significant was the high degree of consistency in the rate of work done by any given lifter in movements which were very similar with respect to joint action, but competitively had very different objectives. The procedure should prove useful in detecting problems in lifting movements that result in power outputs which are low relative to those measured for biomechanically equivalent exertions.
Additive effects of beta-alanine and sodium bicarbonate on upper-body intermittent performance.
Tobias, Gabriel; Benatti, Fabiana Braga; de Salles Painelli, Vitor; Roschel, Hamilton; Gualano, Bruno; Sale, Craig; Harris, Roger C; Lancha, Antonio Herbert; Artioli, Guilherme Gianinni
2013-08-01
We examined the isolated and combined effects of beta-alanine (BA) and sodium bicarbonate (SB) on high-intensity intermittent upper-body performance in judo and jiu-jitsu competitors. 37 athletes were assigned to one of four groups: (1) placebo (PL)+PL; (2) BA+PL; (3) PL+SB or (4) BA+SB. BA or dextrose (placebo) (6.4 g day⁻¹) was ingested for 4 weeks and 500 mg kg⁻¹ BM of SB or calcium carbonate (placebo) was ingested for 7 days during the 4th week. Before and after 4 weeks of supplementation, the athletes completed four 30-s upper-body Wingate tests, separated by 3 min. Blood lactate was determined at rest, immediately after and 5 min after the 4th exercise bout, with perceived exertion reported immediately after the 4th bout. BA and SB alone increased the total work done in +7 and 8 %, respectively. The co-ingestion resulted in an additive effect (+14 %, p < 0.05 vs. BA and SB alone). BA alone significantly improved mean power in the 2nd and 3rd bouts and tended to improve the 4th bout. SB alone significantly improved mean power in the 4th bout and tended to improve in the 2nd and 3rd bouts. BA+SB enhanced mean power in all four bouts. PL+PL did not elicit any alteration on mean and peak power. Post-exercise blood lactate increased with all treatments except with PL+PL. Only BA+SB resulted in lower ratings of perceived exertion (p = 0.05). Chronic BA and SB supplementation alone equally enhanced high-intensity intermittent upper-body performance in well-trained athletes. Combined BA and SB promoted a clear additive ergogenic effect.
Freitas, Tomás T; Calleja-González, Julio; Alarcón, Francisco; Alcaraz, Pedro E
2016-02-01
This study aimed to investigate the acute effects of two different resistance circuit training protocols on basketball players' physical and technical performance and rating of perceived exertion (RPE). In a repeated-measures, crossover experimental design, 9 semiprofessional basketball players performed a Power Circuit Training (PCT; 45% 1RM) and a High-Resistance Circuit Training (HRC; 6RM), on consecutive weeks. Vertical and horizontal jump performance, 3-points shooting accuracy, repeated-sprint ability (RSA), agility, and upper body power output were measured before and after training. The RPE was assessed 20 minutes after resistance training. One-way repeated-measures analysis of variance showed performance decrements in vertical jump height and peak power, horizontal jump distance, 3-points percentage, bench-press power output, RSA total and ideal time, and agility T-Test at total time following HRC, but not PCT (p ≤ 0.05). The RPE was higher in HRC compared with PCT. The results of this study indicated that HRC was perceived as being harder and produced higher fatigue levels, which in turn lowered acute performance. However, low-to-moderate intensity loads did not negatively affect performance. Thus, completing a PCT session may be the most appropriate option before a practice or game as it avoids acute-resistance-training-induced performance decrements. However, if the objective of the basketball session is to develop or perfect technical skills during fatiguing conditions, HRC may be the more suitable option.
The Fallacies of Flatness: Thomas Friedman's "The World Is Flat"
ERIC Educational Resources Information Center
Abowitz, Kathleen Knight; Roberts, Jay
2007-01-01
Thomas Friedman's best-selling "The World is Flat" has exerted much influence in the west by providing both an accessible analysis of globalization and its economic and social effects, and a powerful cultural metaphor for globalization. In this review, we more closely examine Friedman's notion of the social contract, the moral center of his…
El Sayed, S M; El-Magd, R M Abou; Shishido, Y; Chung, S P; Diem, T H; Sakai, T; Watanabe, H; Kagami, S; Fukui, K
2012-02-01
Oxidative stress-energy depletion therapy using oxidative stress induced by D-amino acid oxidase (DAO) and energy depletion induced by 3-bromopyruvate (3BP) was reported recently (El Sayed et al., Cancer Gene Ther., 19, 1-18, 2012). Even in the presence of oxygen, cancer cells oxidize glucose preferentially to produce lactate (Warburg effect) which seems vital for cancer microenvironment and progression. 3BP is a closely related structure to lactate and pyruvate and may antagonize their effects as a novel mechanism of its action. Pyruvate exerted a potent H(2)O(2) scavenging effect to exogenous H(2)O(2), while lactate had no scavenging effect. 3BP induced H(2)O(2) production. Pyruvate protected against H(2)O(2)-induced C6 glioma cell death, 3BP-induced C6 glioma cell death but not against DAO/D-serine-induced cell death, while lactate had no protecting effect. Lactate and pyruvate protected against 3BP-induced C6 glioma cell death and energy depletion which were overcome with higher doses of 3BP. Lactate and pyruvate enhanced migratory power of C6 glioma which was blocked by 3BP. Pyruvate and lactate did not protect against C6 glioma cell death induced by other glycolytic inhibitors e.g. citrate (inhibitor of phosphofructokinase) and sodium fluoride (inhibitor of enolase). Serial doses of 3BP were synergistic with citrate in decreasing viability of C6 glioma cells and spheroids. Glycolysis subjected to double inhibition using 3BP with citrate depleted ATP, clonogenic power and migratory power of C6 glioma cells. 3BP induced a caspase-dependent cell death in C6 glioma. 3BP was powerful in decreasing viability of human glioblastoma multiforme cells (U373MG) and C6 glioma in a dose- and time-dependent manner.
Miller, Larry E; Zimmermann, Angela K; Herbert, William G
2016-01-01
Powered exoskeletons are designed to safely facilitate ambulation in patients with spinal cord injury (SCI). We conducted the first meta-analysis of the available published research on the clinical effectiveness and safety of powered exoskeletons in SCI patients. MEDLINE and EMBASE databases were searched for studies of powered exoskeleton-assisted walking in patients with SCI. Main outcomes were analyzed using fixed and random effects meta-analysis models. A total of 14 studies (eight ReWalk™, three Ekso™, two Indego(®), and one unspecified exoskeleton) representing 111 patients were included in the analysis. Training programs were typically conducted three times per week, 60-120 minutes per session, for 1-24 weeks. Ten studies utilized flat indoor surfaces for training and four studies incorporated complex training, including walking outdoors, navigating obstacles, climbing and descending stairs, and performing activities of daily living. Following the exoskeleton training program, 76% of patients were able to ambulate with no physical assistance. The weighted mean distance for the 6-minute walk test was 98 m. The physiologic demand of powered exoskeleton-assisted walking was 3.3 metabolic equivalents and rating of perceived exertion was 10 on the Borg 6-20 scale, comparable to self-reported exertion of an able-bodied person walking at 3 miles per hour. Improvements in spasticity and bowel movement regularity were reported in 38% and 61% of patients, respectively. No serious adverse events occurred. The incidence of fall at any time during training was 4.4%, all occurring while tethered using a first-generation exoskeleton and none resulting in injury. The incidence of bone fracture during training was 3.4%. These risks have since been mitigated with newer generation exoskeletons and refinements to patient eligibility criteria. Powered exoskeletons allow patients with SCI to safely ambulate in real-world settings at a physical activity intensity conducive to prolonged use and known to yield health benefits.
Miller, Larry E; Zimmermann, Angela K; Herbert, William G
2016-01-01
Background Powered exoskeletons are designed to safely facilitate ambulation in patients with spinal cord injury (SCI). We conducted the first meta-analysis of the available published research on the clinical effectiveness and safety of powered exoskeletons in SCI patients. Methods MEDLINE and EMBASE databases were searched for studies of powered exoskeleton-assisted walking in patients with SCI. Main outcomes were analyzed using fixed and random effects meta-analysis models. Results A total of 14 studies (eight ReWalk™, three Ekso™, two Indego®, and one unspecified exoskeleton) representing 111 patients were included in the analysis. Training programs were typically conducted three times per week, 60–120 minutes per session, for 1–24 weeks. Ten studies utilized flat indoor surfaces for training and four studies incorporated complex training, including walking outdoors, navigating obstacles, climbing and descending stairs, and performing activities of daily living. Following the exoskeleton training program, 76% of patients were able to ambulate with no physical assistance. The weighted mean distance for the 6-minute walk test was 98 m. The physiologic demand of powered exoskeleton-assisted walking was 3.3 metabolic equivalents and rating of perceived exertion was 10 on the Borg 6–20 scale, comparable to self-reported exertion of an able-bodied person walking at 3 miles per hour. Improvements in spasticity and bowel movement regularity were reported in 38% and 61% of patients, respectively. No serious adverse events occurred. The incidence of fall at any time during training was 4.4%, all occurring while tethered using a first-generation exoskeleton and none resulting in injury. The incidence of bone fracture during training was 3.4%. These risks have since been mitigated with newer generation exoskeletons and refinements to patient eligibility criteria. Conclusion Powered exoskeletons allow patients with SCI to safely ambulate in real-world settings at a physical activity intensity conducive to prolonged use and known to yield health benefits. PMID:27042146
Carlier, Mauraine; Delevoye-Turrell, Yvonne
2017-01-01
Moderate physical activity can be experienced by some as pleasurable and by others as discouraging. This may be why many people lack sufficient motivation to participate in the recommended 150 minutes of moderately intense exercise per week. In the present study, we assessed how pleasure and enjoyment were modulated differently by one's tolerance to self-paced physical activity. Sixty-three healthy individuals were allocated to three independent experimental conditions: a resting condition (watching TV), a cycling in silence condition, and a cycling in music condition. The tolerance threshold was assessed using the PRETIE-Questionnaire. Physical activity consisted in cycling during 30 minutes, at an intensity perceived as "somewhat difficult" on the Ratings of Perceived Exertion Scale. While controlling for self-reported physical activity level, results revealed that for the same perception of exertion and a similar level of enjoyment, the High Tolerance group produced more power output than the Low Tolerance group. There was a positive effect of music for High Tolerant individuals only, with music inducing greater power output and more pleasure. There was an effect of music on heart rate frequency in the Low Tolerant individuals without benefits in power output or pleasure. Our results suggest that for Low Tolerant individuals, energizing environments can interfere with the promised (positive) distracting effects of music. Hence, tolerance to physical effort must be taken into account to conceive training sessions that seek to use distracting methods as means to sustain pleasurable exercising over time.
Sartorio, Alessandro; Maffiuletti, Nicola A; Agosti, Fiorenza; Marinone, Pier Giulio; Ottolini, Saverio; Lafortuna, Claudio L
2004-04-01
To investigate the effectiveness of a body mass reduction programme entailing diet caloric restriction and moderate physical activity with or without supplementary treatment with recombinant (r) GH or steroids to improve body composition and muscle performance in severely obese women aged 61-75 years. Twenty women were randomly assigned to one of three groups: body mass reduction alone; body mass reduction plus rGH; body mass reduction plus nandrolone undecanoate. Body composition, isotonic muscle strength and anaerobic power output during jumping were determined before and after the 3-week period. Whatever the experimental group considered, body mass (P<0.01), body mass index (P<0.05) and fat mass (P<0.05) decreased significantly, whereas muscle strength and power increased significantly (P<0.05) after the intervention. Small body mass reductions after 3 weeks of energy-restricted diet combined with moderate aerobic and strength exercise are associated with significant improvements in upper and lower limb muscle strength and power and reduction of fat mass in severely obese women aged 61-75 years. Although the association of rGH or nandrolone undecanoate does not appear to exert additional effects on body composition and muscle performance attained by body mass reduction alone, further additional studies with larger study groups, different dosages and more prolonged periods are required for definitive conclusions to be drawn.
ERIC Educational Resources Information Center
Schatz, Mona Struhsaker; Gaddis, Stephen R.; Zimmerman, Toni Schindler
Story-telling and family play can exert powerful effects on children. Some beliefs, values, and personal life-style choices that relate to how play is created are examined. Using the primary concepts in "narrative therapy,""adventure-based programming," and "family play therapy," play is employed to create an empowerment framework to consider the…
Targeted Deletion of miR-132/-212 Impairs Memory and Alters the Hippocampal Transcriptome
ERIC Educational Resources Information Center
Hansen, Katelin F.; Sakamoto, Kensuke; Aten, Sydney; Snider, Kaitlin H.; Loeser, Jacob; Hesse, Andrea M.; Page, Chloe E.; Pelz, Carl; Arthur, J. Simon C.; Impey, Soren; Obrietan, Karl
2016-01-01
miR-132 and miR-212 are structurally related microRNAs that have been found to exert powerful modulatory effects within the central nervous system (CNS). Notably, these microRNAs are tandomly processed from the same noncoding transcript, and share a common seed sequence: thus it has been difficult to assess the distinct contribution of each…
Ergonomic analysis of fastening vibration based on ISO Standard 5349 (2001).
Joshi, Akul; Leu, Ming; Murray, Susan
2012-11-01
Hand-held power tools used for fastening operations exert high dynamic forces on the operator's hand-arm, potentially causing injuries to the operator in the long run. This paper presents a study that analyzed the vibrations exerted by two hand-held power tools used for fastening operations with the operating exhibiting different postures. The two pneumatic tools, a right-angled nut-runner and an offset pistol-grip, are used to install shearing-type fasteners. A tri-axial accelerometer is used to measure the tool's vibration. The position and orientation of the transducer mounted on the tool follows the ISO-5349 Standard. The measured vibration data is used to compare the two power tools at different operating postures. The data analysis determines the number of years required to reach a 10% probability of developing finger blanching. The results indicate that the pistol-grip tool induces more vibration in the hand-arm than the right-angled nut-runner and that the vibrations exerted on the hand-arm vary for different postures. Copyright © 2012 Elsevier Ltd and The Ergonomics Society. All rights reserved.
Looking Out From the Top: Differential Effects of Status and Power on Perspective Taking.
Blader, Steven L; Shirako, Aiwa; Chen, Ya-Ru
2016-06-01
The impact of hierarchical rank on perspective taking is both practically and theoretically important, prompting considerable research attention to this issue. However, prior research has primarily examined how power affects perspective taking, and has neglected to investigate the impact of status (i.e., the respect and esteem that an individual holds in the eyes of others). Yet status represents a distinct and ubiquitous basis of hierarchical differentiation, one that may profoundly affect perspective taking. The current research addresses this gap, theorizing and testing the prediction that high status enhances perspective taking, in contrast to prior research that has generally found that high power diminishes perspective taking. Five studies, examining various forms of perspective taking across diverse paradigms, provide converging evidence that status and power exert differential effects on perspective taking. Moreover, these studies provide insight regarding the distinction between status and power, as well as the distinct psychology associated with status. © 2016 by the Society for Personality and Social Psychology, Inc.
Young Children's Use of Contrast in Word Learning: The Case of Proper Names
ERIC Educational Resources Information Center
Hall, D. Geoffrey; Rhemtulla, Mijke
2014-01-01
Recent research has established that contrast can exert a powerful effect on early word learning. This study examined the role of contrast in young children's ability to learn proper names. Preschoolers heard a novel word for an unfamiliar stuffed animal in the presence of a second stuffed animal of either the same or a different kind.…
ERIC Educational Resources Information Center
Muskin, Joshua A.; Kamime, Abdelhak; Adlaoui, Abdellah
2011-01-01
The empowerment literature has tended to focus on reinforcing the capacity of local populations to act effectively in promoting change on their own behalf. Borrowing from the social capital literature, achieving greater empowerment might be linked also to the actions and aims of the already powerful. A group might endeavor to exert its ability to…
Phan, Hop V; Hai, Faisal I; McDonald, James A; Khan, Stuart J; van de Merwe, Jason P; Leusch, Frederic D L; Zhang, Ren; Price, William E; Broeckmann, Andreas; Nghiem, Long D
2015-09-01
The impacts of four simulated hazardous events, namely, aeration failure, power loss, and chemical shocks (ammonia or bleach) on the performance of an anoxic-aerobic membrane bioreactor (MBR) receiving real wastewater were investigated. Hazardous events could alter pH and/or oxidation reduction potential of the mixed liquor and inhibit biomass growth, thus affecting the removal of bulk organics, nutrients and trace organic contaminants (TrOC). Chemical shocks generally exerted greater impact on MBR performance than aeration/power failure events, with ammonia shock exerting the greatest impact. Compared to total organic carbon, nutrient removal was more severely affected. Removal of the hydrophilic TrOCs that are resistant and/or occur at high concentrations in wastewater was notably affected. The MBR effectively reduced estrogenicity and toxicity from wastewater, but chemical shocks could temporarily increase the endocrine activity of the effluent. Depending on the chemical shock-dose and the membrane flux, hazardous events can exacerbate membrane fouling. Copyright © 2015 Elsevier Ltd. All rights reserved.
Bimodal control of stimulated food intake by the endocannabinoid system.
Bellocchio, Luigi; Lafenêtre, Pauline; Cannich, Astrid; Cota, Daniela; Puente, Nagore; Grandes, Pedro; Chaouloff, Francis; Piazza, Pier Vincenzo; Marsicano, Giovanni
2010-03-01
Activation of cannabinoid type-1 receptors (CB(1)) is universally recognized as a powerful endogenous orexigenic signal, but the detailed underlying neuronal mechanisms are not fully understood. Using combined genetic and pharmacological approaches in mice, we found that ventral striatal CB(1) receptors exerted a hypophagic action through inhibition of GABAergic transmission. Conversely, brain CB(1) receptors modulating excitatory transmission mediated the well-known orexigenic effects of cannabinoids.
Processing of thermionic power on an electrically propelled spacecraft
NASA Technical Reports Server (NTRS)
Macie, T. W.
1973-01-01
A study to define the power processing equipment required between a thermionic reactor and an array of mercury-ion thrusters for a nuclear electric propulsion system is reported. Observations and recommendations that resulted from this study were: (1) the preferred thermionic-fuel-element source voltages are 23 V or higher; (2) transistor characteristics exert a strong effect on power processor mass; (3) the power processor mass could be considerably reduced should the magnetic materials that exhibit low losses at high frequencies, that have a high Curie point, and that can operate at 15 to 20 kG become avaliable; (4) electrical component packaging on the radiator could reduce the area that is sensitive to meteoroid penetration, thereby reducing the meteoroid shielding mass requirement; (5) an experimental model of the power processor design should be built and tested to verify the efficiencies, masses, and all the automatic operational aspects of the design.
Power in the hypnotic relationship: therapeutic or abusive?
Walling, D P; Levine, R E
1997-01-01
The unique relationship between hypnotist and subject has been theorized as one explanation for the effectiveness of hypnosis. This relationship carries a power differential, present in most therapeutic relationships, but accentuated by hypnosis. The power differential is sometimes perceived as the ability of the hypnotist to control the subject. Perceptions of hypnosis offered by stage hypnotists, the popular media, and some clinicians perpetuate the notion that the hypnotist has the ability to exert undue influence upon the client. The present article examines the relationship between hypnotist and subject focusing on issues of power and control. The authors examine the unique dynamics accompanying the use of hypnosis and their impact on the therapeutic dyad. Evidence is offered demonstrating the power differential, and how this differential can serve as either a positive or negative agent of change. Therapists should be aware of the dynamics created by using hypnosis. Implications for training therapists in the use of hypnosis are suggested.
Using homogenization, sonication and thermo-sonication to inactivate fungi
Bevilacqua, Antonio; Sinigaglia, Milena; Corbo, Maria Rosaria
2016-01-01
Ultrasound (US), Thermo-sonication (TS) and High Pressure Homogenization (HPH) were studied as tools to inactivate the spores of Penicillium spp. and Mucor spp. inoculated in distilled water. For US, the power ranged from 40% to 100%, pulse from 2 to 10 s, and duration of the treatment from 2 to 10 min. TS was performed combining US (40–80% of power, for 8 min and pulse of 2 s) with a thermal treatment (50, 55 and 60°C at 4, 8 and 12 min). Homogenization was done at 30–150 MPa for 1, 2 and 3 times. Power was the most important factors to determine the antifungal effect of US and TS towards the conidia of Penicillium spp.; on the other hand, in US treatments Mucor spp. was also affected by pulse and time. HPH exerted a significant antifungal effect only if the highest pressures were applied for 2–3 times. PMID:27375964
Power sharing. A transformational strategy for nurse retention, effectiveness, and extra effort.
Trofino, Joan
2003-01-01
Power sharing with staff nurses is an essential strategy for organizational transformation. The current competitive health care environment requires a powerful team of participants, including staff at all levels, to provide health care in mutual partnership. The challenges of today's competitive and global environment call for collegial relationships among nurse executive leadership, middle nurse managers, and staff nurses. Research has demonstrated that middle nurse managers maintain primary responsibility for staff nurse retention. A higher retention rate was reported among nurses who were very satisfied with their nurse managers. Nurses considered favorably nurse managers who value staff contributions, promote information sharing, and exert influence for a stable work environment. Furthermore, as staff nurse satisfaction increased, effectiveness and extra effort also increased when staff nurses perceived transformational leadership strategies. Strategies for power sharing include serving as role models and mentors, energizing staff, resisting attitudes of staff ownership, reducing staff nurse stress of leader presence, and information sharing and commendations at meetings.
Correlates of healthcare and financial decision making among older adults without dementia.
Stewart, Christopher C; Yu, Lei; Wilson, Robert S; Bennett, David A; Boyle, Patricia A
2018-03-22
Healthcare and financial decision making among older persons has been previously associated with cognition, health and financial literacy, and risk aversion; however, the manner by which these resources support decision making remains unclear, as past studies have not systematically investigated the pathways linking these resources with decision making. In the current study, we use path analysis to examine the direct and indirect pathways linking age, education, cognition, literacy, and risk aversion with decision making. We also decomposed literacy into its subcomponents, conceptual knowledge and numeracy, in order to examine their associations with decision making. Participants were 937 community-based older adults without dementia from the Rush Memory and Aging Project who completed a battery of cognitive tests and assessments of healthcare and financial decision making, health and financial literacy, and risk aversion. Age and education exerted effects on decision making, but nearly two thirds of their effects were indirect, working mostly through cognition and literacy. Cognition exerted a strong direct effect on decision making and a robust indirect effect working primarily through literacy. Literacy also exerted a powerful direct effect on decision making, as did its subcomponents, conceptual knowledge and numeracy. The direct effect of risk aversion was comparatively weak. In addition to cognition, health and financial literacy emerged as independent and primary correlates of healthcare and financial decision making. These findings suggest specific actions that might be taken to optimize healthcare and financial decision making and, by extension, improve health and well-being in advanced age. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
ERIC Educational Resources Information Center
Dustrud, Stephanine A. Martin
2012-01-01
Power is embedded within all aspects of human experience and has been a fundamental constituent in social systems since the beginning of recorded history. Power exists in every organization and evolves as the culture of the organization exerts its influence. Organizational structures and systems dictate the elements of power, its use, and its…
The effect of caffeine as an ergogenic aid in anaerobic exercise.
Woolf, Kathleen; Bidwell, Wendy K; Carlson, Amanda G
2008-08-01
The study examined caffeine (5 mg/kg body weight) vs. placebo during anaerobic exercise. Eighteen male athletes (24.1+/-5.8 yr; BMI 26.4+/-2.2 kg/m2) completed a leg press, chest press, and Wingate test. During the caffeine trial, more total weight was lifted with the chest press, and a greater peak power was obtained during the Wingate test. No differences were observed between treatments for the leg press and average power, minimum power, and power drop (Wingate test). There was a significant treatment main effect found for postexercise glucose and insulin concentrations; higher concentrations were found in the caffeine trial. A significant interaction effect (treatment and time) was found for cortisol and glucose concentrations; both increased with caffeine and decreased with placebo. Postexercise systolic blood pressure was significantly higher during the caffeine trial. No differences were found between treatments for serum free-fatty-acid concentrations, plasma lactate concentrations, serum cortisol concentrations, heart rate, and rating of perceived exertion. Thus, a moderate dose of caffeine resulted in more total weight lifted for the chest press and a greater peak power attained during the Wingate test in competitive athletes.
Baklouti, Hana; Aloui, Asma; Chtourou, Hamdi; Briki, Walid; Chaouachi, Anis; Souissi, Nizar
2015-01-01
The purpose of this study was to examine the effect of active warm-up duration on short-term maximal performance assessed during Ramadan in the afternoon. Twelve healthy active men took part in the study. The experimental design consisted of four test sessions conducted at 5 p.m., before and during Ramadan, either with a 5-minute or a 15-minute warm-up. The warm-up consisted in pedaling at 50% of the power output obtained at the last stage of a submaximal multistage cycling test. During each session, the subjects performed two vertical jump tests (squat jump and counter movement jump) for measurement of vertical jump height followed by a 30-second Wingate test for measurement of peak and mean power. Oral temperature was recorded at rest and after warming-up. Moreover, ratings of perceived exertion were obtained immediately after the Wingate test. Oral temperature was higher before Ramadan than during Ramadan at rest, and was higher after the 15-minute warm-up than the 5-minute warm-up both before and during Ramadan. In addition, vertical jump heights were not significantly different between the two warm-up conditions before and during Ramadan, and were lower during Ramadan than before Ramadan after both warm-up conditions. Peak and mean power were not significantly different between the two warm-up durations before Ramadan, but were significantly higher after the 5-minute warm-up than the 15-minute warm-up during Ramadan. Moreover, peak and mean power were lower during Ramadan than before Ramadan after both warm-up conditions. Furthermore, ratings of perceived exertion were higher after the 15-minute warm-up than the 5-minute warm-up only during Ramadan. The prolonged active warm-up has no effect on vertical jump height but impairs anaerobic power assessed during Ramadan in the afternoon.
Baklouti, Hana; Aloui, Asma; Chtourou, Hamdi; Briki, Walid; Chaouachi, Anis; Souissi, Nizar
2015-01-01
Aim The purpose of this study was to examine the effect of active warm-up duration on short-term maximal performance assessed during Ramadan in the afternoon. Methods Twelve healthy active men took part in the study. The experimental design consisted of four test sessions conducted at 5 p.m., before and during Ramadan, either with a 5-minute or a 15-minute warm-up. The warm-up consisted in pedaling at 50% of the power output obtained at the last stage of a submaximal multistage cycling test. During each session, the subjects performed two vertical jump tests (squat jump and counter movement jump) for measurement of vertical jump height followed by a 30-second Wingate test for measurement of peak and mean power. Oral temperature was recorded at rest and after warming-up. Moreover, ratings of perceived exertion were obtained immediately after the Wingate test. Results Oral temperature was higher before Ramadan than during Ramadan at rest, and was higher after the 15-minute warm-up than the 5-minute warm-up both before and during Ramadan. In addition, vertical jump heights were not significantly different between the two warm-up conditions before and during Ramadan, and were lower during Ramadan than before Ramadan after both warm-up conditions. Peak and mean power were not significantly different between the two warm-up durations before Ramadan, but were significantly higher after the 5-minute warm-up than the 15-minute warm-up during Ramadan. Moreover, peak and mean power were lower during Ramadan than before Ramadan after both warm-up conditions. Furthermore, ratings of perceived exertion were higher after the 15-minute warm-up than the 5-minute warm-up only during Ramadan. Conclusion The prolonged active warm-up has no effect on vertical jump height but impairs anaerobic power assessed during Ramadan in the afternoon. PMID:25646955
Multiple Mechanisms of Anti-Cancer Effects Exerted by Astaxanthin
Zhang, Li; Wang, Handong
2015-01-01
Astaxanthin (ATX) is a xanthophyll carotenoid which has been approved by the United States Food and Drug Administration (USFDA) as food colorant in animal and fish feed. It is widely found in algae and aquatic animals and has powerful anti-oxidative activity. Previous studies have revealed that ATX, with its anti-oxidative property, is beneficial as a therapeutic agent for various diseases without any side effects or toxicity. In addition, ATX also shows preclinical anti-tumor efficacy both in vivo and in vitro in various cancer models. Several researches have deciphered that ATX exerts its anti-proliferative, anti-apoptosis and anti-invasion influence via different molecules and pathways including signal transducer and activator of transcription 3 (STAT3), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and peroxisome proliferator-activated receptor gamma (PPARγ). Hence, ATX shows great promise as chemotherapeutic agents in cancer. Here, we review the rapidly advancing field of ATX in cancer therapy as well as some molecular targets of ATX. PMID:26184238
Effect of HeartMate left ventricular assist device on cardiac autonomic nervous activity.
Kim, S Y; Montoya, A; Zbilut, J P; Mawulawde, K; Sullivan, H J; Lonchyna, V A; Terrell, M R; Pifarré, R
1996-02-01
Clinical performance of a left ventricular assist device is assessed via hemodynamic parameters and end-organ function. This study examined effect of a left ventricular assist device on human neurophysiology. This study evaluated the time course change of cardiac autonomic activity of 3 patients during support with a left ventricular assist device before cardiac transplantation. Cardiac autonomic activity was determined by power spectral analysis of short-term heart rate variability. The heart rate variability before cardiac transplantation was compared with that on the day before left ventricular assist device implantation. The standard deviation of the mean of the R-R intervals of the electrocardiogram, an index of vagal activity, increased to 27 +/- 7 ms from 8 +/- 0.6 ms. The modulus of power spectral components increased. Low frequency (sympathetic activity) and high frequency power (vagal activity) increased by a mean of 9 and 22 times of each baseline value (low frequency power, 5.2 +/- 3.0 ms2; high frequency power, 2.1 +/- 0.7 ms2). The low over high frequency power ratio decreased substantially, indicating an improvement of cardiac sympatho-vagal balance. The study results suggest that left ventricular assist device support before cardiac transplantation may exert a favorable effect on cardiac autonomic control in patients with severe heart failure.
Microgravity Fluid Separation Physics: Experimental and Analytical Results
NASA Technical Reports Server (NTRS)
Shoemaker, J. Michael; Schrage, Dean S.
1997-01-01
Effective, low power, two-phase separation systems are vital for the cost-effective study and utilization of two-phase flow systems and flow physics of two-phase flows. The study of microgravity flows have the potential to reveal significant insight into the controlling mechanisms for the behavior of flows in both normal and reduced gravity environments. The microgravity environment results in a reduction in gravity induced buoyancy forces acting on the discrete phases. Thus, surface tension, viscous, and inertial forces exert an increased influence on the behavior of the flow as demonstrated by the axisymmetric flow patterns. Several space technology and operations groups have studied the flow behavior in reduced gravity since gas-liquid flows are encountered in several systems such as cabin humidity control, wastewater treatment, thermal management, and Rankine power systems.
[Hypoxia and memory. Specific features of nootropic agents effects and their use].
Voronina, T A
2000-01-01
Hypoxia and hypoxic adaptation are powerful factors of controlling memory and behavior processes. Acute hypoxia exerts a differential impact on different deficits of mnestic and cognitive functions. Instrumental reflexes of active and passive avoidance, negative learning, behavior with a change in the stereotype of learning are more greatly damaged. Memory with spatial and visual differentiation and their rearrangement change to a lesser extent and conditional reflexes are not deranged. In this contract, altitude hypoxic adaptation enhances information fixation and increases the degree and duration of retention of temporary relations. Nootropic agents with an antihypoxic action exert a marked effect on hypoxia-induced cognitive and memory disorders and the magnitude of this effect depends on the ration of proper nootropic to antihypoxic components in the spectrum of the drugs' pharmacological activity. The agents that combine a prevailing antiamnestic effect and a marked and moderate antihypoxic action (mexidole, nooglutil, pyracetam, beglymin, etc.) are most effective in eliminating different hypoxia-induced cognitive and memory disorders, nootropic drugs that have a pronounced antiamnestic activity (centrophenoxine, etc.) and no antihypoxic component also restore the main types of mnestic disorders after hypoxia, but to a lesser extent.
Turhan, Semra Akkaya; Toker, Ebru
2015-01-01
To evaluate the lens edge interaction with the ocular surface with different edge designs using optical coherence tomography and to examine the effect of lens power on the lens edge interactions. Four types of silicone hydrogel lenses with different edge designs (round-, semi-round-, chisel-, and knife-edged) at six different powers (+5.0, +3.0, +1.0, -1.0, -3.0, and -5.0 diopters) were fitted to both eyes of 20 healthy volunteers. Optical coherence tomography images were taken at the corneal center and at the limbus within 15-30 minutes after insertion. The images were evaluated with respect to two parameters: conjunctival indentation exerted by the lens edge; and the tear film gaps between the posterior surface of the lens and the ocular surface. The amount of conjunctival indentation was measured with the distortion angle of the conjunctiva at the lens edge. The degree of conjunctival indentation was highest with the chisel-edged design followed by the semi-round design (P<0.0001). Knife- and round-edged lenses exerted similar levels of conjunctival indentation that was significantly lower compared to chisel-edged lens (P<0.001). For each one of the tested lens edge designs, no significant difference was observed in the conjunctival indentation with respect to lens power. The chisel-edged lens produced the highest amount of conjunctival indentation for each one of the six lens powers (P<0.0001). Post-lens tear film gaps at the limbus were observed at most in the round-edge design (P=0.001). The fitting properties of contact lenses may be influenced by their edge design but not by their lens power.
Turhan, Semra Akkaya; Toker, Ebru
2015-01-01
Purpose To evaluate the lens edge interaction with the ocular surface with different edge designs using optical coherence tomography and to examine the effect of lens power on the lens edge interactions. Methods Four types of silicone hydrogel lenses with different edge designs (round-, semi-round-, chisel-, and knife-edged) at six different powers (+5.0, +3.0, +1.0, −1.0, −3.0, and −5.0 diopters) were fitted to both eyes of 20 healthy volunteers. Optical coherence tomography images were taken at the corneal center and at the limbus within 15–30 minutes after insertion. The images were evaluated with respect to two parameters: conjunctival indentation exerted by the lens edge; and the tear film gaps between the posterior surface of the lens and the ocular surface. The amount of conjunctival indentation was measured with the distortion angle of the conjunctiva at the lens edge. Results The degree of conjunctival indentation was highest with the chisel-edged design followed by the semi-round design (P<0.0001). Knife- and round-edged lenses exerted similar levels of conjunctival indentation that was significantly lower compared to chisel-edged lens (P<0.001). For each one of the tested lens edge designs, no significant difference was observed in the conjunctival indentation with respect to lens power. The chisel-edged lens produced the highest amount of conjunctival indentation for each one of the six lens powers (P<0.0001). Post-lens tear film gaps at the limbus were observed at most in the round-edge design (P=0.001). Conclusion The fitting properties of contact lenses may be influenced by their edge design but not by their lens power. PMID:26045658
Bertucci, William M; Arfaoui, Ahlem; Duc, Sebastien; Letellier, Thierry; Brikci, Abderrahim
2015-01-01
The purpose of this study was to investigate the effect of whole body vibration in oxygen uptake during intense squatting exercise with an added weight and whole body vibration compared with the same exercise without vibration. Nine male sub- jects performed three trials of dynamic squatting with an additional load of 50% of their body weight during 3 min. One trial without vibration, one trial with the frequency of 40 Hz and amplitude of 2 mm and one trial with the frequency of 40 Hz and amplitude of 4 mm. The results showed no difference between the three experimental trials in relative and absolute oxygen uptake. However, the metabolic power and energy expended in whole body vibration (2 mm) were significantly different from exercise without vibration. The data analysis also showed a significant difference in rating of perceived exertion with whole body vibration (4 mm) compared with the exercise without vibration. Results showed that the addition of vibration stimulus has an increase in the energy expenditure particularly with 40 Hz and 2 mm amplitude, suggesting that the high metabolic power during heavy resistance training could be increased by the addition of vibration stimulation. Involuntary contractions generated by the vibration can be used by coaches to increase the intensity of heavy resistance training or to increase the energy expended during the workouts if the goal is a decrease of body mass.
The Effects of Mental Fatigue on Physical Performance: A Systematic Review.
Van Cutsem, Jeroen; Marcora, Samuele; De Pauw, Kevin; Bailey, Stephen; Meeusen, Romain; Roelands, Bart
2017-08-01
Mental fatigue is a psychobiological state caused by prolonged periods of demanding cognitive activity. It has recently been suggested that mental fatigue can affect physical performance. Our objective was to evaluate the literature on impairment of physical performance due to mental fatigue and to create an overview of the potential factors underlying this effect. Two electronic databases, PubMed and Web of Science (until 28 April 2016), were searched for studies designed to test whether mental fatigue influenced performance of a physical task or influenced physiological and/or perceptual responses during the physical task. Studies using short (<30 min) self-regulatory depletion tasks were excluded from the review. A total of 11 articles were included, of which six were of strong and five of moderate quality. The general finding was a decline in endurance performance (decreased time to exhaustion and self-selected power output/velocity or increased completion time) associated with a higher than normal perceived exertion. Physiological variables traditionally associated with endurance performance (heart rate, blood lactate, oxygen uptake, cardiac output, maximal aerobic capacity) were unaffected by mental fatigue. Maximal strength, power, and anaerobic work were not affected by mental fatigue. The duration and intensity of the physical task appear to be important factors in the decrease in physical performance due to mental fatigue. The most important factor responsible for the negative impact of mental fatigue on endurance performance is a higher perceived exertion.
Inclusive Adult Learning Environments. ERIC Digest No. 162.
ERIC Educational Resources Information Center
Imel, Susan
Adult educators are recognizing that factors in the learning environment related to psychological, social, and cultural conditions exert a powerful influence on learners' growth and development. Current discussions on learning environments have broadened to include the need to confront issues of sexism and racism, interlocking systems of power and…
Quantitative modeling and optimization of magnetic tweezers.
Lipfert, Jan; Hao, Xiaomin; Dekker, Nynke H
2009-06-17
Magnetic tweezers are a powerful tool to manipulate single DNA or RNA molecules and to study nucleic acid-protein interactions in real time. Here, we have modeled the magnetic fields of permanent magnets in magnetic tweezers and computed the forces exerted on superparamagnetic beads from first principles. For simple, symmetric geometries the magnetic fields can be calculated semianalytically using the Biot-Savart law. For complicated geometries and in the presence of an iron yoke, we employ a finite-element three-dimensional PDE solver to numerically solve the magnetostatic problem. The theoretical predictions are in quantitative agreement with direct Hall-probe measurements of the magnetic field and with measurements of the force exerted on DNA-tethered beads. Using these predictive theories, we systematically explore the effects of magnet alignment, magnet spacing, magnet size, and of adding an iron yoke to the magnets on the forces that can be exerted on tethered particles. We find that the optimal configuration for maximal stretching forces is a vertically aligned pair of magnets, with a minimal gap between the magnets and minimal flow cell thickness. Following these principles, we present a configuration that allows one to apply > or = 40 pN stretching forces on approximately 1-microm tethered beads.
Quantitative Modeling and Optimization of Magnetic Tweezers
Lipfert, Jan; Hao, Xiaomin; Dekker, Nynke H.
2009-01-01
Abstract Magnetic tweezers are a powerful tool to manipulate single DNA or RNA molecules and to study nucleic acid-protein interactions in real time. Here, we have modeled the magnetic fields of permanent magnets in magnetic tweezers and computed the forces exerted on superparamagnetic beads from first principles. For simple, symmetric geometries the magnetic fields can be calculated semianalytically using the Biot-Savart law. For complicated geometries and in the presence of an iron yoke, we employ a finite-element three-dimensional PDE solver to numerically solve the magnetostatic problem. The theoretical predictions are in quantitative agreement with direct Hall-probe measurements of the magnetic field and with measurements of the force exerted on DNA-tethered beads. Using these predictive theories, we systematically explore the effects of magnet alignment, magnet spacing, magnet size, and of adding an iron yoke to the magnets on the forces that can be exerted on tethered particles. We find that the optimal configuration for maximal stretching forces is a vertically aligned pair of magnets, with a minimal gap between the magnets and minimal flow cell thickness. Following these principles, we present a configuration that allows one to apply ≥40 pN stretching forces on ≈1-μm tethered beads. PMID:19527664
Promoting cooperation and trust in "noisy" situations: the power of generosity.
Klapwijk, Anthon; Van Lange, Paul A M
2009-01-01
The authors present an interdependence theoretical framework and advance the argument that generosity serves the important purpose of communicating trust, which is assumed to be of utmost importance to coping with incidents of negative noise (i.e., when the other every now and then behaves less cooperatively than intended). Using a new social dilemma task (the parcel delivery paradigm), it was hypothesized that incidents of negative noise would exert detrimental effects on trust and trust-related judgments and experiences, as well as cooperation, and that relative to tit for tat and self-regarding strategies (stingy or unconditionally cooperative strategies), other-regarding strategies (i.e., unconditional cooperation and generosity) would be more effective at reducing such as detrimental effects. Results from 2 studies provided strong support for these hypotheses, suggesting that the power of generosity is underestimated in the extant literature, especially in its ability to maintain or build trust, which is essential for coping with noise.
DeWall, C Nathan; Baumeister, Roy F; Mead, Nicole L; Vohs, Kathleen D
2011-01-01
When leaders perform solitary tasks, do they self-regulate to maximize their effort, or do they reduce effort and conserve their resources? Our model suggests that power motivates self-regulation toward effective performance-unless the task is perceived as unworthy of leaders. Our 1st studies showed that power improves self-regulation and performance, even when resources for self-regulation are low (ego depletion). Additional studies showed that leaders sometimes disdain tasks they deem unworthy, by withholding effort (and therefore performing poorly). Ironically, during ego depletion, leaders skip the appraisal and, therefore, work hard regardless of task suitability, so that depleted leaders sometimes outperform nondepleted ones. Our final studies replicated these patterns with different tasks and even with simple manipulation of framing and perception of the same task (Experiment 5). Experiment 4 also showed that the continued high exertion of leaders when depleted takes a heavy toll, resulting in larger impairments later. The judicious expenditure of self-control resources among powerful people may help them prioritize their efforts to pursue their goals effectively. (PsycINFO Database Record (c) 2010 APA, all rights reserved).
NASA Astrophysics Data System (ADS)
Takahashi, Kazunori; Ando, Akira
2017-05-01
Individual measurements of forces exerted to an upstream back wall, a radial source wall, and a magnetic field of a helicon plasma thruster, which has two solenoids upstream and downstream of a radiofrequency antenna, are precisely measured. Two different structures of magnetic field lines in the source are tested, where the solenoid current is supplied to either only the downstream solenoid or to both the solenoids. It is observed that the high density plasma exists upstream of the rf antenna when both the solenoids are powered, while the maximum density exists near the rf antenna when only the downstream solenoid is powered. Although the force exerted to the back wall is increased for the two solenoids case, the axial momentum lost to the radial wall is simultaneously enhanced; then the total force exerted to the whole structure of the thruster is found to be very similar for the two magnetic field configurations. It is shown that the individual force measurement provides useful information on the plasma momentum interacting with the physical boundaries and the magnetic fields.
Sheng, Hong; Nakamura, Keisuke; Kanno, Taro; Sasaki, Keiichi; Niwano, Yoshimi
2015-01-01
The bactericidal effect of hydroxyl radical (·OH) generated by combination of photolysis of hydrogen peroxide (H2O2) and sonolysis of water was examined under the condition in which the yield of ·OH increased additively when H2O2 aqueous solution was concomitantly irradiated with laser and ultrasound. The suspension of Staphylococcus aureus mixed with the different concentrations of H2O2 was irradiated simultaneously with a laser light (wavelength: 405 nm, irradiance: 46 and 91 mW/cm2) and ultrasound (power: 30 w, frequency: 1.65 MHz) at 20 ± 1°C of the water bulk temperature for 2 min. The combination of laser and ultrasound irradiation significantly reduced the viable bacterial count in comparison with the laser irradiation of H2O2 alone. By contrast, the ultrasound irradiation alone exerted almost no bactericidal effect. These results suggested that the combination effect of photolysis of H2O2 and sonolysis of water on bactericidal activity was synergistic. A multi-way analysis of variance also revealed that the interaction of H2O2 concentration, laser power and ultrasound irradiation significantly affected the bactericidal activity. Since the result of oxidative DNA damage evaluation demonstrated that the combination of laser and ultrasound irradiation significantly induced oxidative damage of bacterial DNA in comparison with the laser irradiation of H2O2 alone, it was suggested that the combination effect of photolysis of H2O2 and sonolysis of water on bactericidal activity would be exerted via oxidative damage of cellular components such as DNA.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hacke, P.
2012-03-01
Over the past decade, there have been observations of module degradation and power loss because of the stress that system voltage bias exerts. This results in part from qualification tests and standards note adequately evaluating for the durability of modules to the long-term effects of high voltage bias that they experience in fielded arrays. This talk deals with factors for consideration, progress, and information still needed for a standardized test for degradation due to system voltage stress.
A Model for Predicting Integrated Man-Machine System Reliability: Model Logic and Description
1974-11-01
3. Fatigue buildup curve. The common requirement of all tests on the Dynamic Strength factor is for the muscles involved to propel, support, or...move the body repeatedly or to support it continuously over time. The tests of our Static Strength factor emphasize the lifting power of the muscles ...or the pounds of pressure which the muscles can exert. ... In contrast to Dynamic Strength the force exerted is against external objects, rather
Musical agency reduces perceived exertion during strenuous physical performance
Fritz, Thomas Hans; Hardikar, Samyogita; Demoucron, Matthias; Niessen, Margot; Demey, Michiel; Giot, Olivier; Li, Yongming; Haynes, John-Dylan; Villringer, Arno; Leman, Marc
2013-01-01
Music is known to be capable of reducing perceived exertion during strenuous physical activity. The current interpretation of this modulating effect of music is that music may be perceived as a diversion from unpleasant proprioceptive sensations that go along with exhaustion. Here we investigated the effects of music on perceived exertion during a physically strenuous task, varying musical agency, a task that relies on the experience of body proprioception, rather than simply diverting from it. For this we measured psychologically indicated exertion during physical workout with and without musical agency while simultaneously acquiring metabolic values with spirometry. Results showed that musical agency significantly decreased perceived exertion during workout, indicating that musical agency may actually facilitate physically strenuous activities. This indicates that the positive effect of music on perceived exertion cannot always be explained by an effect of diversion from proprioceptive feedback. Furthermore, this finding suggests that the down-modulating effect of musical agency on perceived exertion may be a previously unacknowledged driving force for the development of music in humans: making music makes strenuous physical activities less exhausting. PMID:24127588
Musical agency reduces perceived exertion during strenuous physical performance.
Fritz, Thomas Hans; Hardikar, Samyogita; Demoucron, Matthias; Niessen, Margot; Demey, Michiel; Giot, Olivier; Li, Yongming; Haynes, John-Dylan; Villringer, Arno; Leman, Marc
2013-10-29
Music is known to be capable of reducing perceived exertion during strenuous physical activity. The current interpretation of this modulating effect of music is that music may be perceived as a diversion from unpleasant proprioceptive sensations that go along with exhaustion. Here we investigated the effects of music on perceived exertion during a physically strenuous task, varying musical agency, a task that relies on the experience of body proprioception, rather than simply diverting from it. For this we measured psychologically indicated exertion during physical workout with and without musical agency while simultaneously acquiring metabolic values with spirometry. Results showed that musical agency significantly decreased perceived exertion during workout, indicating that musical agency may actually facilitate physically strenuous activities. This indicates that the positive effect of music on perceived exertion cannot always be explained by an effect of diversion from proprioceptive feedback. Furthermore, this finding suggests that the down-modulating effect of musical agency on perceived exertion may be a previously unacknowledged driving force for the development of music in humans: making music makes strenuous physical activities less exhausting.
Kobayashi, Y; Narazaki, K; Akagi, R; Nakagaki, K; Kawamori, N; Ohta, K
2013-09-01
For achieving accurate and safe measurements of the force and power exerted on a load during resistance exercise, the Smith machine has been used instead of free weights. However, because some Smith machines possess counterweights, the equation for the calculation of force and power in this system should be different from the one used for free weights. The purpose of this investigation was to calculate force and power using an equation derived from a dynamic equation for a Smith machine with counterweights and to determine the differences in force and power calculated using 2 different equations. One equation was established ignoring the effect of the counterweights (Method 1). The other equation was derived from a dynamic equation for a barbell and counterweight system (Method 2). 9 female collegiate judo athletes performed bench throws using a Smith machine with a counterweight at 6 different loading conditions. Barbell displacement was recorded using a linear position transducer. The force and power were subsequently calculated by Methods 1 and 2. The results showed that the mean and peak power and force in Method 1 were significantly lower relative to those of Method 2 under all loading conditions. These results indicate that the mean and peak power and force during bench throwing using a Smith machine with counterweights would be underestimated when the calculations used to determine these parameters do not account for the effect of counterweights. © Georg Thieme Verlag KG Stuttgart · New York.
Authority Base, Denomination, Moral Philosophy and the Power Strategies Used by Clergymen.
ERIC Educational Resources Information Center
Falbo, Toni; And Others
Clergymen are regarded by their congregations as having the authority to influence church members and clergymen are expected to exert influence. Three types of clerical authority have been identified: charismatic, traditional, and legal-rational. The common assumption that people select power strategies that are consistent with their perceptions…
[Effect of CO2 laser on prostheses used in middle ear surgery].
Szymański, Marcin
2005-01-01
The use of CO2 laser is advocated in primary and revision stapes surgery. The aim of the study was to assess the effect of CO2 laser on stapes prostheses. CO2 laser was applied on several types of stapes prostheses and PORPs, with power settings suggested by the manufacturer (continuous wave, 2 W and 6 W; 0,05 s). Application of the laser on stainless steel or titanium prosthesis did not exert any effect on the structure of the prosthesis. The use of the laser on the Teflon piston caused superficial burning with power 2 W, and melting and holes in the piston with power settings at 6W. Similar plastipore prostheses were melting. Hydroxyapatite PORP shattered after application of the laser energy. Teflon and hydroxyapatite prostheses are easily damaged by the laser energy, therefore applying a laser on them should be avoided. CO2 laser can be used on stainless steel and titanium prostheses without risk of damaging them. However the possibility of transmission of heat to the vestibule has to be taken into consideration.
2013-01-01
and levels of corruption, as well as more ephemeral soft power considerations like national reputation, moral clout, and cultural influence.7 For...of carefully calibrated issues that balance underlying national interests and plausible opportunities for exerting influence. Middle power diplomacy...World (University Park: Pennsylvania State University Press, 1997); Björn Hettne, András Inotai and Osvaldo Sunkel, eds., Gobalism and the New
Graham-Paulson, Terri; Perret, Claudio; Goosey-Tolfrey, Victoria
2018-05-03
Caffeine's (CAF) ability to influence upper-body exercise endurance performance may be related to an individual's training status. This case study therefore aimed to investigate the ergogenic effects of CAF dose on 20-km time trial (TT) performance of an elite male paratriathlete (wheelchair user; age = 46 years, body mass = 76.9 kg, body fat = 25.4%, and handcycling [Formula: see text]). The athlete completed four 20-km handcycling TTs on a Cyclus II ergometer under controlled laboratory conditions following the ingestion of 2, 4, and 6 mg/kg CAF or placebo (PLA). Blood lactate concentration, power output, arousal, and ratings of perceived exertion were recorded. Ingestion of 2, 4, and 6 mg/kg CAF resulted in a 2%, 1.5%, and 2.7% faster TT compared with PLA (37:40 min:s). The participant's blood lactate concentration increased throughout all trials and was greater during CAF compared with PLA. There were no obvious differences in ratings of perceived exertion between trials despite different performance times. Baseline arousal scores differed between PLA and 4 mg/kg CAF (1 = low), and 2 and 6 mg/kg CAF (3 = moderate). Arousal increased at each time point following the ingestion of 4 and 6 mg/kg CAF. The largest CAF dose resulted in a positive pacing strategy, which, when combined with an end spurt, resulted in the fastest TT. CAF improved 20-km TT performance of an elite male paratriathlete, which may be related to greater arousal and an increased power output for a given rating of perceived exertion.
Weakley, Jonathon Js; Till, Kevin; Read, Dale B; Phibbs, Padraic J; Roe, Gregory; Darrall-Jones, Joshua; Jones, Ben L
2017-08-04
Training that is efficient and effective is of great importance to an athlete. One method of improving efficiency is by incorporating supersets into resistance training routines. However, the structuring of supersets is still unexplored. Therefore, the purpose of this study was to assess the effects of agonist-antagonist (A-A), alternate peripheral (A-P), and similar biomechanical (SB) superset configurations on rate of perceived exertion (RPE), kinetic and kinematic changes during the bench press. 10 subjects performed resistance training protocols in a randomized-crossover design, with magnitude-based inferences assessing changes/differences within and between protocols. Changes in RPE were very likely and almost certainly greater in the A-P and SB protocols when compared with the A-A, while all superset protocols had very likely to almost certain reductions in mean velocity and power from baseline. Reductions in mean velocity and power were almost certainly greater in the SB protocol, with differences between the A-A and A-P protocols being unclear. Decreases in peak force were likely and almost certain in the A-A and SB protocols respectively, with changes in A-P being unclear. Differences between these protocols showed likely greater decreases in SB peak forces when compared to A-A, with all other superset comparisons being unclear. This study demonstrates the importance of exercise selection when incorporating supersets into a training routine. It is suggested that the practitioner uses A-A supersets when aiming to improve training efficiency and minimize reductions in kinetic and kinematic output of the agonist musculature while completing the barbell bench press.
NASA Astrophysics Data System (ADS)
Oviatt, Eric; Patsiaouris, Konstantinos; Denardo, Bruce
2009-11-01
A sound source of finite size produces a diverging traveling wave in an unbounded fluid. A rigid body that is small compared to the wavelength experiences an attractive radiation force (toward the source). An attractive force is also exerted on the fluid itself. The effect can be demonstrated with a styrofoam ball suspended near a loudspeaker that is producing sound of high amplitude and low frequency (for example, 100 Hz). The behavior can be understood and roughly calculated as a time-averaged Bernoulli effect. A rigorous scattering calculation yields a radiation force that is within a factor of two of the Bernoulli result. For a spherical wave, the force decreases as the inverse fifth power of the distance from the source. Applications of the phenomenon include ultrasonic filtration of liquids and the growth of supermassive black holes that emit sound waves in a surrounding plasma. An experiment is being conducted in an anechoic chamber with a 1-inch diameter aluminum ball that is suspended from an analytical balance. Directly below the ball is a baffled loudspeaker that exerts an attractive force that is measured by the balance.
Factors affecting success of an integrated community-based telehealth system.
Hsieh, Hui-Lung; Tsai, Chung-Hung; Chih, Wen-Hai; Lin, Huei-Hsieh
2015-01-01
The rise of chronic and degenerative diseases in developed countries has become one critical epidemiologic issue. Telehealth can provide one viable way to enhance health care, public health, and health education delivery and support. The study aims to empirically examine and evaluate the success factors of community-based telehealth system adoption. The valid 336 respondents are the residents of a rural community in Taiwan. The structural equation modeling (SEM) was used to assess the proposed model applied to telehealth. The findings showed the research model had good explanatory power and fitness. Also, the findings indicated that system quality exerted the strongest overall effect on intention to use. Furthermore, service quality exerted the strongest overall effect on user satisfaction. The findings also illustrated that the joint effects of three intrinsic qualities (system quality, information quality, and service quality) on use were mediated by user satisfaction and intention to use. The study implies that community-based telehealth service providers should improve three intrinsic qualities to enhance user satisfaction and intention to use, which in turn can lead to increase the usage of the telehealth equipment. The integrated community-based telehealth system may become an innovative and suitable way to deliver better care to the residents of communities.
Stochastic dynamics and mechanosensitivity of myosin II minifilaments
NASA Astrophysics Data System (ADS)
Albert, Philipp J.; Erdmann, Thorsten; Schwarz, Ulrich S.
2014-09-01
Tissue cells are in a state of permanent mechanical tension that is maintained mainly by myosin II minifilaments, which are bipolar assemblies of tens of myosin II molecular motors contracting actin networks and bundles. Here we introduce a stochastic model for myosin II minifilaments as two small myosin II motor ensembles engaging in a stochastic tug-of-war. Each of the two ensembles is described by the parallel cluster model that allows us to use exact stochastic simulations and at the same time to keep important molecular details of the myosin II cross-bridge cycle. Our simulation and analytical results reveal a strong dependence of myosin II minifilament dynamics on environmental stiffness that is reminiscent of the cellular response to substrate stiffness. For small stiffness, minifilaments form transient crosslinks exerting short spikes of force with negligible mean. For large stiffness, minifilaments form near permanent crosslinks exerting a mean force which hardly depends on environmental elasticity. This functional switch arises because dissociation after the power stroke is suppressed by force (catch bonding) and because ensembles can no longer perform the power stroke at large forces. Symmetric myosin II minifilaments perform a random walk with an effective diffusion constant which decreases with increasing ensemble size, as demonstrated for rigid substrates with an analytical treatment.
Laboratory versus outdoor cycling conditions: differences in pedaling biomechanics.
Bertucci, William; Grappe, Frederic; Groslambert, Alain
2007-05-01
The aim of our study was to compare crank torque profile and perceived exertion between the Monark ergometer (818 E) and two outdoor cycling conditions: level ground and uphill road cycling. Seven male cyclists performed seven tests in seated position at different pedaling cadences: (a) in the laboratory at 60, 80, and 100 rpm; (b) on level terrain at 80 and 100 rpm; and (c) on uphill terrain (9.25% grade) at 60 and 80 rpm. The cyclists exercised for 1 min at their maximal aerobic power. The Monark ergometer and the bicycle were equipped with the SRM Training System (Schoberer, Germany) for the measurement of power output (W), torque (Nxm), pedaling cadence (rpm), and cycling velocity (kmxh-1). The most important findings of this study indicate that at maximal aerobic power the crank torque profiles in the Monark ergometer (818 E) were significantly different (especially on dead points of the crank cycle) and generate a higher perceived exertion compared with road cycling conditions.
From Meet and Confer to Collective Bargaining to Collaborative Bargaining.
ERIC Educational Resources Information Center
Wagner, Shelby E.
For most of America's history, teachers have had few labor negotiating rights and little power to exert them. The National Labor Relations Act established the National Labor Relations Board and helped teachers gain more power in labor negotiations. Many worker rights gained from the 1930s through the 1970s were undermined by the increased…
Bryce, Thomas N.; Dijkers, Marcel P.
2015-01-01
Background: Powered exoskeletons have been demonstrated as being safe for persons with spinal cord injury (SCI), but little is known about how users learn to manage these devices. Objective: To quantify the time and effort required by persons with SCI to learn to use an exoskeleton for assisted walking. Methods: A convenience sample was enrolled to learn to use the first-generation Ekso powered exoskeleton to walk. Participants were given up to 24 weekly sessions of instruction. Data were collected on assistance level, walking distance and speed, heart rate, perceived exertion, and adverse events. Time and effort was quantified by the number of sessions required for participants to stand up, walk for 30 minutes, and sit down, initially with minimal and subsequently with contact guard assistance. Results: Of 22 enrolled participants, 9 screen-failed, and 7 had complete data. All of these 7 were men; 2 had tetraplegia and 5 had motor-complete injuries. Of these, 5 participants could stand, walk, and sit with contact guard or close supervision assistance, and 2 required minimal to moderate assistance. Walk times ranged from 28 to 94 minutes with average speeds ranging from 0.11 to 0.21 m/s. For all participants, heart rate changes and reported perceived exertion were consistent with light to moderate exercise. Conclusion: This study provides preliminary evidence that persons with neurological weakness due to SCI can learn to walk with little or no assistance and light to somewhat hard perceived exertion using a powered exoskeleton. Persons with different severities of injury, including those with motor complete C7 tetraplegia and motor incomplete C4 tetraplegia, may be able to learn to use this device. PMID:26364280
Kozlowski, Allan J; Bryce, Thomas N; Dijkers, Marcel P
2015-01-01
Powered exoskeletons have been demonstrated as being safe for persons with spinal cord injury (SCI), but little is known about how users learn to manage these devices. To quantify the time and effort required by persons with SCI to learn to use an exoskeleton for assisted walking. A convenience sample was enrolled to learn to use the first-generation Ekso powered exoskeleton to walk. Participants were given up to 24 weekly sessions of instruction. Data were collected on assistance level, walking distance and speed, heart rate, perceived exertion, and adverse events. Time and effort was quantified by the number of sessions required for participants to stand up, walk for 30 minutes, and sit down, initially with minimal and subsequently with contact guard assistance. Of 22 enrolled participants, 9 screen-failed, and 7 had complete data. All of these 7 were men; 2 had tetraplegia and 5 had motor-complete injuries. Of these, 5 participants could stand, walk, and sit with contact guard or close supervision assistance, and 2 required minimal to moderate assistance. Walk times ranged from 28 to 94 minutes with average speeds ranging from 0.11 to 0.21 m/s. For all participants, heart rate changes and reported perceived exertion were consistent with light to moderate exercise. This study provides preliminary evidence that persons with neurological weakness due to SCI can learn to walk with little or no assistance and light to somewhat hard perceived exertion using a powered exoskeleton. Persons with different severities of injury, including those with motor complete C7 tetraplegia and motor incomplete C4 tetraplegia, may be able to learn to use this device.
Zahabi, Maryam; Zhang, Wenjuan; Pankok, Carl; Lau, Mei Ying; Shirley, James; Kaber, David
2017-11-01
Many occupations require both physical exertion and cognitive task performance. Knowledge of any interaction between physical demands and modalities of cognitive task information presentation can provide a basis for optimising performance. This study examined the effect of physical exertion and modality of information presentation on pattern recognition and navigation-related information processing. Results indicated males of equivalent high fitness, between the ages of 18 and 34, rely more on visual cues vs auditory or haptic for pattern recognition when exertion level is high. We found that navigation response time was shorter under low and medium exertion levels as compared to high intensity. Navigation accuracy was lower under high level exertion compared to medium and low levels. In general, findings indicated that use of the haptic modality for cognitive task cueing decreased accuracy in pattern recognition responses. Practitioner Summary: An examination was conducted on the effect of physical exertion and information presentation modality in pattern recognition and navigation. In occupations requiring information presentation to workers, who are simultaneously performing a physical task, the visual modality appears most effective under high level exertion while haptic cueing degrades performance.
Stopping power: Effect of the projectile deceleration
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kompaneets, Roman, E-mail: kompaneets@mpe.mpg.de; Ivlev, Alexei V.; Morfill, Gregor E.
2014-11-15
The stopping force is the force exerted on the projectile by its wake. Since the wake does not instantly adjust to the projectile velocity, the stopping force should be affected by the projectile deceleration caused by the stopping force itself. We address this effect by deriving the corresponding correction to the stopping force in the cold plasma approximation. By using the derived expression, we estimate that if the projectile is an ion passing through an electron-proton plasma, the correction is small when the stopping force is due to the plasma electrons, but can be significant when the stopping force ismore » due to the protons.« less
Prior Acute Mental Exertion in Exercise and Sport
Silva-Júnior, Fernando Lopes e; Emanuel, Patrick; Sousa, Jordan; Silva, Matheus; Teixeira, Silmar; Pires, Flávio Oliveira; Machado, Sérgio; Arias-Carrion, Oscar
2016-01-01
Introduction: Mental exertion is a psychophysiological state caused by sustained and prolonged cognitive activity. The understanding of the possible effects of acute mental exertion on physical performance, and their physiological and psychological responses are of great importance for the performance of different occupations, such as military, construction workers, athletes (professional or recreational) or simply practicing regular exercise, since these occupations often combine physical and mental tasks while performing their activities. However, the effects of implementation of a cognitive task on responses to aerobic exercise and sports are poorly understood. Our narrative review aims to provide information on the current research related to the effects of prior acute mental fatigue on physical performance and their physiological and psychological responses associated with exercise and sports. Methods: The literature search was conducted using the databases PubMed, ISI Web of Knowledge and PsycInfo using the following terms and their combinations: “mental exertion”, “mental fatigue”, “mental fatigue and performance”, “mental exertion and sports” “mental exertion and exercise”. Results: We concluded that prior acute mental exertion affects effectively the physiological and psychophysiological responses during the cognitive task, and performance in exercise. Conclusion: Additional studies involving prior acute mental exertion, exercise/sports and physical performance still need to be carried out in order to analyze the physiological, psychophysiological and neurophysiological responses subsequently to acute mental exertion in order to identify cardiovascular factors, psychological, neuropsychological associates. PMID:27867415
Pacifico, Severina; Gallicchio, Marialuisa; Fiorentino, Antonio; Fischer, Anna; Meyer, Ulrich; Stintzing, Florian Conrad
2012-11-01
In the course of a screening program on quince phytochemicals, two complex preparations were in the focus of the present study, i.e., a lipophilic quince wax extract (QWE) and an aqueous fermented one (QAFE). While the phytochemical composition has been described earlier, the intention of the current investigation was to complement these data with an extensive antioxidant screening of these preparations including their radical scavenging and reductive power as well as their antilipoperoxidative properties. The Quince Aqueous Fermented Extract (QAFE) effectively scavenged the radical target species exhibiting ID(50) values equal to 68.8 μg/mL towards DPPH· and 73.7 μg/mL towards the anion superoxide radical. Quince wax extract (QWE) was more effective at preventing the formation of thiobarbituric reactive species than QAFE exhibiting an ID(50) value equal to 48.9 μg/mL. Moreover the cytotoxic effects towards human HepG2, A549, and HeLa cell lines were evaluated. The two preparations exerted a different effect on the proliferation of the three tested cell lines. Noteworthy, QAFE was almost always more active than QWE but, sometimes, its effects seemed to be strongly dependent on exposure time. Data obtained demonstrate clearly that both hydrophilic and lipophilic quince preparations are non-toxic and exert health-promoting properties. Copyright © 2012 Elsevier Ltd. All rights reserved.
Bochkarev, V K; Teleshova, E S; Siuniakov, S A; Davydova, D V; Neznamov, G G
2008-01-01
An effect of a new nootropic drug noopept on the dynamics of main EEG rhythms and narrow-band spectral EEG characteristics in patients with cerebral asthenic and cognitive disturbances caused by traumas or vascular brain diseases has been studied. Noopept caused the EEG changes characteristic of the action of nootropics: the increase of alpha- and beta-rhythms power and reduction of delta-rhythms power. The reaction of alpha-rhythm was provided mostly by the dynamics of its low and medium frequencies (6,7-10,2 Hz), the changes of beta-rhythm were augmented in frontal and attenuated in occipital areas. The analysis of frequency and spatial structure of EEG changes reveals that noopept exerts a nonspecific activation and anxyolytic effect. The differences in EEG changes depending on the brain pathology were found. The EEG indices of nootropic effect of the drug were most obvious in cerebral vascular diseases. The EEG changes in posttraumatic brain lesion were less typical.
Tax on sugar sweetened beverages in Spain.
Ortún, Vicente; G López-Valcárcel, Beatriz; Pinilla, Jaime
2016-10-13
This article provides a critical review about the challenges that taxes on sugary drinks as an instrument of health policy must face to reverse the trend of the current epidemics of obesity. We analyzed the experiences of the leading countries, particularly Mexico, and reflect on the counterweight exerted by the industry against obesity policies, and on the power of lobbyists. Those tax policies for public health have to overcome the enormous strength of the industry, which is exerted in several-science and research, brand reputation, influence on regulators-levels. We suggest that a specific tax on sugary drinks has enough potential to reduce noncommunicable diseases and risk -diabetes, Hypertriglyceridemia, hyperholesterolemia LDL, hypertension- via reduced consumption thanks to the high price elasticity of those drinks. Furthermore, the effects are amplified even in the medium term, once established new habits to healthier eating. These taxes could encourage business innovation without inflicting costs of lost jobs and contribute to reducing the social gradient in obesity.
Caldwell, Lydia K; DuPont, William H; Beeler, Matthew K; Post, Emily M; Barnhart, Emily C; Hardesty, Vincent H; Anders, John P; Borden, Emily C; Volek, Jeff S; Kraemer, William J
2018-03-01
The purpose of this double-blind, placebo-controlled investigation was to examine the effects of a Korean Ginseng (GINST15) on measures of perception and physical performance following an acute bout of resistance exercise. Ten women (age: 38.7 ± 7.8 years; height: 1.64 ± 0.05 m; body mass: 76.0 ± 11.6 kg) and nine men (age: 41.2. ± 9.7 years; height: 1.77 ± 0.05 m; body mass: 88.5 ± 5.0 kg) completed the investigation. Participants were randomized to a three-cycle testing scheme consisting of high dose ginseng (HIGH: 960 mg/day), low dose ginseng (LOW: 160 mg/day) and placebo (PBO: 0 mg/day). After 14 days of supplementation participants returned to the laboratory for an acute resistance exercise trial (5 sets of 12 repetitions of the leg press at 70% of one-repetition-maximum [1RM]). Ratings of perceived exertion (RPE) were assessed after each set. Muscle pain/soreness was assessed before exercise and 24 hours post exercise. Psychomotor performance and peak power were measured before exercise, immediately post exercise and 24 hours after exercise. Each treatment cycle was separated by a minimum one-week washout period. HIGH significantly reduced perceived exertion during exercise. HIGH and LOW significantly reduced change in muscle soreness at 24 hours post exercise. Analysis of peak power demonstrated the presence of responders (n = 13) and non-responders (n = 6). Responders showed a significant effect of HIGH GINST15 on maintenance of neuromuscular function. The appearance of responders and non-responders, could explain the mixed literature base on the ergogenic properties of ginseng.
Lim, Hayoung A; Miller, Karen; Fabian, Chuck
2011-01-01
The present study investigated the effects of a Neurologic Music Therapy (NMT) sensory-motor rehabilitation technique, Therapeutic Instrumental Music Performance (TIMP) as compared to Traditional Occupational Therapy (TOT), on endurance, self-perceived fatigue, and self-perceived exertion of 35 hospitalized patients in physical rehabilitation. The present study attempted to examine whether an active musical experience such as TIMP with musical cueing (i.e., rhythmic auditory cueing) during physical exercises influences one's perception of pain, fatigue, and exertion. All participants were diagnosed with a neurologic disorder or had recently undergone orthopedic surgery. Investigators measured the effects of TOT and TIMP during upper extremity exercise of the less affected or stronger upper extremity. Results showed no significant difference on endurance measures between the 2 treatment conditions (TIMP and TOT). Statistically significant differences were found between TIMP and TOT when measuring their effects on perceived exertion and perceived fatigue. TIMP resulted in significantly less perception of fatigue and exertion levels than TOT. TIMP can be used foran effective sensory-motor rehabilitation technique to decrease perceived exertion and fatigue level of inpatients in physical rehabilitation.
Effects of radiant heat exposure on pacing pattern during a 15-km cycling time trial.
Levels, Koen; de Koning, Jos; Broekhuijzen, Iris; Zwaan, Tamara; Foster, Carl; Daanen, Hein
2014-01-01
The goal of this study was to investigate the effects of different durations of skin temperature manipulation on pacing patterns and performance during a 15-km cycling time trial. Nineteen well-trained men completed three 15-km cycling time trials in 18 °C and 50% relative humidity with 4.5-km (short-heat), 9.0-km (long-heat) or without (control) radiant heat exposure applied by infrared heaters after 1.5 km in the time trial. During the time trials, power output, mean skin temperature, rectal temperature, heart rate and rating of perceived exertion were assessed. The radiant heat exposure resulted in higher mean skin temperature during the time trial for short-heat (35.0 ± 0.6 °C) and long-heat (35.3 ± 0.5 °C) than for control (32.5 ± 1.0 °C; P < 0.001), whereas rectal temperature was similar (P = 0.55). The mean power output was less for short-heat (273 ± 8 W; P = 0.001) and long-heat (271 ± 9 W; P = 0.02) than for control (287 ± 7 W), but pacing patterns did not differ (P = 0.55). Heart rate was greatest in control (177 ± 9 beats · min(-1); P < 0.001), whereas the rating of perceived exertion remained similar. We concluded that a radiant heat exposure and associated higher skin temperature reduced overall performance, but did not modify pacing pattern during a 15-km cycling time trial, regardless of the duration of the exposure.
Self-paced cycling performance and recovery under a hot and highly humid environment after cooling.
Gonzales, B R; Hagin, V; Guillot, R; Placet, V; Monnier-Benoit, P; Groslambert, A
2014-02-01
This study investigated the effects of pre- and post-cooling on self-paced time-trial cycling performance and recovery of cyclists exercising under a hot and highly humid environment (29.92 °C-78.52% RH). Ten male cyclists performed a self-paced 20-min time trial test (TT20) on a cyclo-ergometer while being cooled by a cooling vest and a refrigerating headband during the warm-up and the recovery period. Heart rate, power output, perceived exertion, thermal comfort, skin and rectal temperatures were recorded. Compared to control condition (222.78 ± 47 W), a significant increase (P<0.05) in the mean power output during the TT20 (239.07 ± 45 W; +7.31%) was recorded with a significant (P<0.05) decrease in skin temperature without affecting perceived exertion, heart rate, or rectal temperature at the end of the TT20. However, pace changes occurred independently of skin or rectal temperatures variations but a significant difference (P<0.05) in the body's heat storage was observed between both conditions. This result suggests that a central programmer using body's heat storage as an input may influence self-paced time-trial performance. During the recovery period, post-cooling significantly decreased heart rate, skin and rectal temperatures, and improved significantly (P<0.05) thermal comfort. Therefore, in hot and humid environments, wearing a cooling vest and a refrigerating headband during warm-up improves self-paced performance, and appears to be an effective mean of reaching skin rest temperatures more rapidly during recovery.
Superior Inhibitory Control and Resistance to Mental Fatigue in Professional Road Cyclists.
Martin, Kristy; Staiano, Walter; Menaspà, Paolo; Hennessey, Tom; Marcora, Samuele; Keegan, Richard; Thompson, Kevin G; Martin, David; Halson, Shona; Rattray, Ben
2016-01-01
Given the important role of the brain in regulating endurance performance, this comparative study sought to determine whether professional road cyclists have superior inhibitory control and resistance to mental fatigue compared to recreational road cyclists. After preliminary testing and familiarization, eleven professional and nine recreational road cyclists visited the lab on two occasions to complete a modified incongruent colour-word Stroop task (a cognitive task requiring inhibitory control) for 30 min (mental exertion condition), or an easy cognitive task for 10 min (control condition) in a randomized, counterbalanced cross-over order. After each cognitive task, participants completed a 20-min time trial on a cycle ergometer. During the time trial, heart rate, blood lactate concentration, and rating of perceived exertion (RPE) were recorded. The professional cyclists completed more correct responses during the Stroop task than the recreational cyclists (705±68 vs 576±74, p = 0.001). During the time trial, the recreational cyclists produced a lower mean power output in the mental exertion condition compared to the control condition (216±33 vs 226±25 W, p = 0.014). There was no difference between conditions for the professional cyclists (323±42 vs 326±35 W, p = 0.502). Heart rate, blood lactate concentration, and RPE were not significantly different between the mental exertion and control conditions in both groups. The professional cyclists exhibited superior performance during the Stroop task which is indicative of stronger inhibitory control than the recreational cyclists. The professional cyclists also displayed a greater resistance to the negative effects of mental fatigue as demonstrated by no significant differences in perception of effort and time trial performance between the mental exertion and control conditions. These findings suggest that inhibitory control and resistance to mental fatigue may contribute to successful road cycling performance. These psychobiological characteristics may be either genetic and/or developed through the training and lifestyle of professional road cyclists.
Synchrony and exertion during dance independently raise pain threshold and encourage social bonding
Tarr, Bronwyn; Launay, Jacques; Cohen, Emma; Dunbar, Robin
2015-01-01
Group dancing is a ubiquitous human activity that involves exertive synchronized movement to music. It is hypothesized to play a role in social bonding, potentially via the release of endorphins, which are analgesic and reward-inducing, and have been implicated in primate social bonding. We used a 2 × 2 experimental design to examine effects of exertion and synchrony on bonding. Both demonstrated significant independent positive effects on pain threshold (a proxy for endorphin activation) and in-group bonding. This suggests that dance which involves both exertive and synchronized movement may be an effective group bonding activity. PMID:26510676
Isotope Effects as Probes for Enzyme Catalyzed Hydrogen-Transfer Reactions
Roston, Daniel; Islam, Zahidul; Kohen, Amnon
2015-01-01
Kinetic Isotope effects (KIEs) have long served as a probe for the mechanisms of both enzymatic and solution reactions. Here, we discuss various models for the physical sources of KIEs, how experimentalists can use those models to interpret their data, and how the focus of traditional models has grown to a model that includes motion of the enzyme and quantum mechanical nuclear tunneling. We then present two case studies of enzymes, thymidylate synthase and alcohol dehydrogenase, and discuss how KIEs have shed light on the C-H bond cleavages those enzymes catalyze. We will show how the combination of both experimental and computational studieshas changed our notion of how these enzymes exert their catalytic powers. PMID:23673528
Fwu, Bih-Jen; Chen, Shun-Wen; Wei, Chih-Fen; Wang, Hsiou-Huai
2017-01-01
Previous studies have found that in East Asian Confucian societies, hardworking students are often trapped in a dilemma of enjoying a positive moral image while suffering from emotional distress due to academic failure. This study intends to further explore whether the cultural-specific belief in self-exertion acts as a psychological mechanism to lessen these students’ negative emotions. A group of 288 college students in Taiwan were administered a questionnaire to record their responses to past academic failures. The results from structural equation modeling showed that self-exertion functioned as a mediator between the effects of effort on learning virtues and emotional distress. Self-exertion to fulfill one’s duty to oneself positively mediated the effect of effort on learning virtues, whereas self-exertion to fulfill one’s duty to one’s parents negatively mediated the effect of effort on emotional distress. Theoretical and cultural implications are further discussed. PMID:28119648
Concept Developed for an Implanted Stimulated Muscle-Powered Piezoelectric Generator
NASA Technical Reports Server (NTRS)
Lewandowski, Beth; Kilgore, Kevin; Ercegovic, David; Gustafson, Kenneth
2005-01-01
Implanted electronic devices are typically powered by batteries or transcutaneous power transmission. Batteries must be replaced or recharged, and transcutaneous power sources burden the patient or subject with external equipment prone to failure. A completely self-sustaining implanted power source would alleviate these limitations. Skeletal muscle provides an available autologous power source containing native chemical energy that produces power in excess of the requirements for muscle activation by motor nerve stimulation. A concept has been developed to convert stimulated skeletal muscle power into electrical energy (see the preceding illustration). We propose to connect a piezoelectric generator between a muscle tendon and bone. Electrically stimulated muscle contractions would exert force on the piezoelectric generator, charging a storage circuit that would be used to power the stimulator and other devices.
Effects of caffeine and carbohydrate mouth rinses on repeated sprint performance.
Beaven, C Martyn; Maulder, Peter; Pooley, Adrian; Kilduff, Liam; Cook, Christian
2013-06-01
Our purpose was to examine the effectiveness of carbohydrate and caffeine mouth rinses in enhancing repeated sprint ability. Previously, studies have shown that a carbohydrate mouth rinse (without ingestion) has beneficial effects on endurance performance that are related to changes in brain activity. Caffeine ingestion has also demonstrated positive effects on sprint performance. However, the effects of carbohydrate or caffeine mouth rinses on intermittent sprints have not been examined previously. Twelve males performed 5 × 6-s sprints interspersed with 24 s of active recovery on a cycle ergometer. Twenty-five milliliters of either a noncaloric placebo, a 6% glucose, or a 1.2% caffeine solution was rinsed in the mouth for 5 s prior to each sprint in a double-blinded and balanced cross-over design. Postexercise maximal heart rate and perceived exertion were recorded, along with power measures. A second experiment compared a combined caffeine-carbohydrate rinse with carbohydrate only. Compared with the placebo mouth rinse, carbohydrate substantially increased peak power in sprint 1 (22.1 ± 19.5 W; Cohen's effect size (ES), 0.81), and both caffeine (26.9 ± 26.9 W; ES, 0.71) and carbohydrate (39.1 ± 25.8 W; ES, 1.08) improved mean power in sprint 1. Experiment 2 demonstrated that a combination of caffeine and carbohydrate improved sprint 1 power production compared with carbohydrate alone (36.0 ± 37.3 W; ES, 0.81). We conclude that carbohydrate and (or) caffeine mouth rinses may rapidly enhance power production, which could have benefits for specific short sprint exercise performance. The ability of a mouth-rinse intervention to rapidly improve maximal exercise performance in the absence of fatigue suggests a central mechanism.
Filamentation of a surface plasma wave over a semiconductor-free space interface
NASA Astrophysics Data System (ADS)
Kumar, Gagan; Tripathi, V. K.
2007-12-01
A large amplitude surface plasma wave (SPW), propagating over a semiconductor-free space interface, is susceptible to filamentation instability. A small perturbation in the amplitude of the SPW across the direction of propagation exerts a ponderomotive force on free electrons and holes, causing spatial modulation in free carrier density and hence the effective permittivity ɛeff of the semiconductor. The regions with higher ɛeff attract more power from the nieghborhood, leading to the growth of the perturbation. The growth rate increases with the intensity of the surface wave. It decreases with the frequency of the SPW.
PARS: a web server for the prediction of Protein Allosteric and Regulatory Sites.
Panjkovich, Alejandro; Daura, Xavier
2014-05-01
The regulation of protein activity is a key aspect of life at the molecular level. Unveiling its details is thus crucial to understanding signalling and metabolic pathways. The most common and powerful mechanism of protein-function regulation is allostery, which has been increasingly calling the attention of medicinal chemists due to its potential for the discovery of novel therapeutics. In this context, PARS is a simple and fast method that queries protein dynamics and structural conservation to identify pockets on a protein structure that may exert a regulatory effect on the binding of a small-molecule ligand.
Ouergui, I; Hammouda, O; Chtourou, H; Zarrouk, N; Rebai, H; Chaouachi, A
2013-10-01
Objective of the study was to determine the effects of a kick-boxing match on muscle power of the upper and lower body as well as the associated perceived exertion in young men. Eighteen well trained kick-boxers volunteered to participate in a competitive sparring bout preceded and followed by three anaerobic tests as follow: squat jump (SJ) and counter movement jump (CMJ) for legs and 30-s Wingate test for arms. The sparring bout consisted of three 2 min rounds with 1 min recovery period in-between. Blood lactate (BL), heart rate (HR) and rating of perceived exertion (RPE) were analyzed before and after each round. The results showed that vertical jump distance in SJ and CMJ were significantly lower after the kick-boxing match (27.92±3.84 vs. 25.28±4.39 cm; 29.8±5.33 vs 28.48±4.64 cm, for SJ and CMJ respectively). Likewise, peak and mean power in the Wingate test decreased significantly after the sparring bout (5.89±0. 69 vs. 5.26±0.66 W•kg-1 and 4.51±0.53 vs. 4.12±0.51 W•kg-1 for PP and MP respectively; P<0.001). Moreover, we found a significant increase in BL, HR, and RPE after the kick-boxing match (P<0.001). BL increased significantly after the second and third round from the post round one values' (P<0.001). These findings showed that a single kick-boxing match is of sufficient intensity to stress the anaerobic metabolism. Thus, training protocols should include exercises that train the anaerobic energetic pathways for upper and lower body.
How multiple causes combine: independence constraints on causal inference.
Liljeholm, Mimi
2015-01-01
According to the causal power view, two core constraints-that causes occur independently (i.e., no confounding) and influence their effects independently-serve as boundary conditions for causal induction. This study investigated how violations of these constraints modulate uncertainty about the existence and strength of a causal relationship. Participants were presented with pairs of candidate causes that were either confounded or not, and that either interacted or exerted their influences independently. Consistent with the causal power view, uncertainty about the existence and strength of causal relationships was greater when causes were confounded or interacted than when unconfounded and acting independently. An elemental Bayesian causal model captured differences in uncertainty due to confounding but not those due to an interaction. Implications of distinct sources of uncertainty for the selection of contingency information and causal generalization are discussed.
Kloosterman, Marieke G M; Buurke, Jaap H; de Vries, Wiebe; Van der Woude, Lucas H V; Rietman, Johan S
2015-10-01
This study aims to compare hand-rim and power-assisted hand-rim propulsion on potential risk factors for shoulder overuse injuries: intensity and repetition of shoulder loading and force generation in the extremes of shoulder motion. Eleven experienced hand-rim wheelchair users propelled an instrumented wheelchair on a treadmill while upper-extremity kinematic, kinetic and surface electromyographical data was collected during propulsion with and without power-assist. As a result during power-assisted propulsion the peak resultant force exerted at the hand-rim decreased and was performed with significantly less abduction and internal rotation at the shoulder. At shoulder level the anterior directed force and internal rotation and flexion moments decreased significantly. In addition, posterior and the minimal inferior directed forces and the external rotation moment significantly increased. The stroke angle decreased significantly, as did maximum shoulder flexion, extension, abduction and internal rotation. Stroke-frequency significantly increased. Muscle activation in the anterior deltoid and pectoralis major also decreased significantly. In conclusion, compared to hand-rim propulsion power-assisted propulsion seems effective in reducing potential risk factors of overuse injuries with the highest gain on decreased range of motion of the shoulder joint, lower peak propulsion force on the rim and reduced muscle activity. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.
Motley, R.W.; Glanz, J.
1982-10-25
A device is described for coupling RF power (a plasma sweeper) from RF power introducing means to a plasma having a magnetic field associated therewith comprises at least one electrode positioned near the plasma and near the RF power introducing means. Means are described for generating a static electric field at the electrode directed into the plasma and having a component substantially perpendicular to the plasma magnetic field such that a non-zero vector cross-product of the electric and magnetic fields exerts a force on the plasma causing the plasma to drift.
Do placebo expectations influence perceived exertion during physical exercise?
Mothes, Hendrik; Leukel, Christian; Seelig, Harald; Fuchs, Reinhard
2017-01-01
This study investigates the role of placebo expectations in individuals' perception of exertion during acute physical exercise. Building upon findings from placebo and marketing research, we examined how perceived exertion is affected by expectations regarding a) the effects of exercise and b) the effects of the exercise product worn during the exercise. We also investigated whether these effects are moderated by physical self-concept. Seventy-eight participants conducted a moderate 30 min cycling exercise on an ergometer, with perceived exertion (RPE) measured every 5 minutes. Beforehand, each participant was randomly assigned to 1 of 4 conditions and watched a corresponding film clip presenting "scientific evidence" that the exercise would or would not result in health benefits and that the exercise product they were wearing (compression garment) would additionally enhance exercise benefits or would only be worn for control purposes. Participants' physical self-concept was assessed via questionnaire. Results partially demonstrated that participants with more positive expectations experienced reduced perceived exertion during the exercise. Furthermore, our results indicate a moderator effect of physical self-concept: Individuals with a high physical self-concept benefited (in terms of reduced perceived exertion levels) in particular from an induction of generally positive expectations. In contrast, individuals with a low physical self-concept benefited when positive expectations were related to the exercise product they were wearing. In sum, these results suggest that placebo expectations may be a further, previously neglected class of psychological factors that influence the perception of exertion.
Do placebo expectations influence perceived exertion during physical exercise?
Leukel, Christian; Seelig, Harald; Fuchs, Reinhard
2017-01-01
This study investigates the role of placebo expectations in individuals’ perception of exertion during acute physical exercise. Building upon findings from placebo and marketing research, we examined how perceived exertion is affected by expectations regarding a) the effects of exercise and b) the effects of the exercise product worn during the exercise. We also investigated whether these effects are moderated by physical self-concept. Seventy-eight participants conducted a moderate 30 min cycling exercise on an ergometer, with perceived exertion (RPE) measured every 5 minutes. Beforehand, each participant was randomly assigned to 1 of 4 conditions and watched a corresponding film clip presenting “scientific evidence” that the exercise would or would not result in health benefits and that the exercise product they were wearing (compression garment) would additionally enhance exercise benefits or would only be worn for control purposes. Participants’ physical self-concept was assessed via questionnaire. Results partially demonstrated that participants with more positive expectations experienced reduced perceived exertion during the exercise. Furthermore, our results indicate a moderator effect of physical self-concept: Individuals with a high physical self-concept benefited (in terms of reduced perceived exertion levels) in particular from an induction of generally positive expectations. In contrast, individuals with a low physical self-concept benefited when positive expectations were related to the exercise product they were wearing. In sum, these results suggest that placebo expectations may be a further, previously neglected class of psychological factors that influence the perception of exertion. PMID:28662168
A convex optimization method for self-organization in dynamic (FSO/RF) wireless networks
NASA Astrophysics Data System (ADS)
Llorca, Jaime; Davis, Christopher C.; Milner, Stuart D.
2008-08-01
Next generation communication networks are becoming increasingly complex systems. Previously, we presented a novel physics-based approach to model dynamic wireless networks as physical systems which react to local forces exerted on network nodes. We showed that under clear atmospheric conditions the network communication energy can be modeled as the potential energy of an analogous spring system and presented a distributed mobility control algorithm where nodes react to local forces driving the network to energy minimizing configurations. This paper extends our previous work by including the effects of atmospheric attenuation and transmitted power constraints in the optimization problem. We show how our new formulation still results in a convex energy minimization problem. Accordingly, an updated force-driven mobility control algorithm is presented. Forces on mobile backbone nodes are computed as the negative gradient of the new energy function. Results show how in the presence of atmospheric obscuration stronger forces are exerted on network nodes that make them move closer to each other, avoiding loss of connectivity. We show results in terms of network coverage and backbone connectivity and compare the developed algorithms for different scenarios.
Mutual powerlessness in client participation practices in mental health care.
Broer, Tineke; Nieboer, Anna P; Bal, Roland
2014-04-01
Client participation has become a dominant policy goal in many countries including the Netherlands and is a topic much discussed in the literature. The success of client participation is usually measured in terms of the extent to which clients have a say in the participation process. Many articles have concluded that client participation is limited; professionals often still control the participation process and outcomes. The objective of this study is to gain insight into (i) the practice of client participation within a quality improvement collaborative in mental health care and (ii) the consequences of a Foucauldian conceptualization of power in analysing practices of client participation. We used an ethnographic design consisting of observations of national events and improvement team meetings and interviews with the collaborative's team members and programme managers. Contrary to many studies on client participation, we found both clients and service providers frequently felt powerless in its practice. Professionals and clients alike struggled with the contributions clients could make to the improvement processes and what functions they should fulfil. Moreover, professionals did not want to exert power upon clients, but ironically just for that reason sometimes struggled with shaping practices of client participation. This mutual powerlessness (partly) disappeared when clients helped to determine and execute specific improvement actions instead of participating in improvement teams. Recognizing that power is inescapable might allow for a more substantive discussion concerning the consequences that power arrangements produce, rather than looking at who is exerting how much power. © 2012 John Wiley & Sons Ltd.
Wang, Huali; Zhang, Jinsong; Yu, Hanqing
2007-05-15
Glutathione peroxidase and thioredoxin reductase are major selenoenzymes through which selenium exerts powerful antioxidant effects. Selenium also elicits pro-oxidant effects at toxic levels. The antioxidant and pro-oxidant effects, or bioavailability and toxicity, of selenium depend on its chemical form. Selenomethionine is considered to be the most appropriate supplemental form due to its excellent bioavailability and lower toxicity compared to various selenium compounds. The present studies reveal that, compared with selenomethionine, elemental selenium at nano size (Nano-Se) possesses equal efficacy in increasing the activities of glutathione peroxidase and thioredoxin reductase but has much lower toxicity as indicated by median lethal dose, acute liver injury, and short-term toxicity. Our results suggest that Nano-Se can serve as an antioxidant with reduced risk of selenium toxicity.
Antioxidant and Cytoprotective Effects of Lotus (Nelumbo nucifera) Leaves Phenolic Fraction
Lee, Da-Bin; Kim, Do-Hyung; Je, Jae-Young
2015-01-01
Phenolic rich ethyl acetate fraction (EAF) from lotus leaves was prepared and its bioactive components, antioxidant and cytoprotective effects were investigated. EAF showed high total phenolic content and flavonoid content and contained rutin (11,331.3±4.5 mg/100 g EAF), catechin (10,853.8±5.8 mg/100 g EAF), sinapic acid (1,961.3±5.6 mg/100 g EAF), chlorogenic acid (631.9±2.3 mg/100 g EAF), syringic acid (512.3±2.5 mg/100 g EAF), and quercetin (415.0±2.1 mg/100 g EAF). EAF exerted the IC50 of 4.46 μg/mL and 5.35 μg/mL toward DPPH and ABTS cation radicals, respectively, and showed strong reducing power, which was better than that of ascorbic acid, a positive control. Additionally, EAF protected hydroxyl radical-induced DNA damage indicated by the conversion of supercoiled pBR322 plasmid DNA to the open circular form and inhibited lipid peroxidation of polyunsaturated fatty acid in a linoleic acid emulsion. In cultured hepatocytes, EAF exerted a cytoprotective effect against oxidative stress by inhibiting intracellular reactive oxygen species formation and membrane lipid peroxidation. In addition, depletion of glutathione under oxidative stress was remarkably restored by treatment with EAF. The results suggest that EAF have great potential to be used against oxidative stress-induced health conditions. PMID:25866746
The Economics of Publishing and the Publishing of Economics.
ERIC Educational Resources Information Center
La Manna, Manfredi
2003-01-01
Explores the relationship between economics and scientific journal publishing. Topics include journal pricing in economics; market power exerted by the dominant commercial publisher in economics journal publishing; academic experiments to improve scholarly communication in economics; policies of the United Kingdom Competition Commission; and…
Moya-Ramón, M.; Hernández-Davó, J. L.; Fernandez-Fernandez, J.; Sabido, R.
2017-01-01
Background It has been suggested that strength training effects (i.e. neural or structural) vary, depending on the total repetitions performed and velocity loss in each training set. Purpose The aim of this study is to compare the effects of two training programmes (i.e. one with loads that maximise power output and individualised repetitions, and the other following traditional power training). Methods Twenty-five males were divided into three groups (optimum power [OP = 10], traditional training [TT = 9] and control group [CG = 6]). The training load used for OP was individualised using loads that maximised power output (41.7% ± 5.8 of one repetition maximum [1RM]) and repetitions at maximum power (4 to 9 repetitions, or ‘reps’). Volume (sets x repetitions) was the same for both experimental groups, while intensity for TT was that needed to perform only 50% of the maximum number of possible repetitions (i.e. 61.1%–66.6% of 1RM). The training programme ran over 11 weeks (2 sessions per week; 4–5 sets per session; 3-minute rests between sets), with pre-, intermediate and post-tests which included: anthropometry, 1RM, peak power output (PPO) with 30%, 40% and 50% of 1RM in the bench press throw, and salivary testosterone (ST) and cortisol (SC) concentrations. Rate of perceived exertion (RPE) and power output were recorded in all sessions. Results Following the intermediate test, PPO was increased in the OP group for each load (10.9%–13.2%). Following the post-test, both experimental groups had increased 1RM (11.8%–13.8%) and PPO for each load (14.1%–19.6%). Significant decreases in PPO were found for the TT group during all sets (4.9%–15.4%), along with significantly higher RPE (37%). Conclusion OP appears to be a more efficient method of training, with less neuromuscular fatigue and lower RPE. PMID:29053725
The "Handling" of power in the physician-patient encounter: perceptions from experienced physicians.
Nimmon, Laura; Stenfors-Hayes, Terese
2016-04-18
Modern healthcare is burgeoning with patient centered rhetoric where physicians "share power" equally in their interactions with patients. However, how physicians actually conceptualize and manage their power when interacting with patients remains unexamined in the literature. This study explored how power is perceived and exerted in the physician-patient encounter from the perspective of experienced physicians. It is necessary to examine physicians' awareness of power in the context of modern healthcare that espouses values of dialogic, egalitarian, patient centered care. Thirty physicians with a minimum five years' experience practicing medicine in the disciplines of Internal Medicine, Surgery, Pediatrics, Psychiatry and Family Medicine were recruited. The authors analyzed semi-structured interview data using LeCompte and Schensul's three stage process: Item analysis, Pattern analysis, and Structural analysis. Theoretical notions from Bourdieu's social theory served as analytic tools for achieving an understanding of physicians' perceptions of power in their interactions with patients. The analysis of data highlighted a range of descriptions and interpretations of relational power. Physicians' responses fell under three broad categories: (1) Perceptions of holding and managing power, (2) Perceptions of power as waning, and (3) Perceptions of power as non-existent or irrelevant. Although the "sharing of power" is an overarching goal of modern patient-centered healthcare, this study highlights how this concept does not fully capture the complex ways experienced physicians perceive, invoke, and redress power in the clinical encounter. Based on the insights, the authors suggest that physicians learn to enact ethical patient-centered therapeutic communication through reflective, effective, and professional use of power in clinical encounters.
DOT National Transportation Integrated Search
1982-03-01
Ten healthy men, 20-35 years old, were tested for tolerance to hypoxia, orthostatic stress, and physical fatigue after a period of rest, and, on another occasion, after a period of physical exertion. Exertion consisted of four 10-min periods of pedal...
The Dynamic between National Identity and Foreign Policy in Turkey
2009-12-01
became evermore powerful. But it wasn’t until after the Ottoman Empire’s defeat in World War I that the Allied Powers of France and Britain exerted...This process is quite typical of nation-building as seen throughout 19th to early 20th century Western Europe. For example, “Union with France ...was suffered, not accepted. The fusion with France was accomplished slowly and against the will.”83 The experiences in the market, schools, and
Eddy currents in a conducting sphere
NASA Technical Reports Server (NTRS)
Bergman, John; Hestenes, David
1986-01-01
This report analyzes the eddy current induced in a solid conducting sphere by a sinusoidal current in a circular loop. Analytical expressions for the eddy currents are derived as a power series in the vectorial displacement of the center of the sphere from the axis of the loop. These are used for first order calculations of the power dissipated in the sphere and the force and torque exerted on the sphere by the electromagnetic field of the loop.
Linking language and categorization in infancy
Ferguson, Brock; Waxman, Sandra
2017-01-01
Language exerts a powerful influence on our concepts. We review evidence documenting the developmental origins of a precocious link between language and object categories in very young infants. This collection of studies documents a cascading process in which early links between language and cognition provide the foundation for later, more precise ones. We propose that, early in life, language promotes categorization at least in part through its status as a social, communicative signal. But over the first year, infants home in on the referential power of language and, by their second year, begin teasing apart distinct kinds of names (e.g., nouns, adjectives) and their relation to distinct kinds of concepts (e.g., object categories, properties). To complement this proposal, we also relate this evidence to several alternative accounts of language’s effect on categorization, appealing to similarity (labels-as-features), familiarity (auditory overshadowing), and communicative biases (natural pedagogy). PMID:27830633
Linking language and categorization in infancy.
Ferguson, Brock; Waxman, Sandra
2017-05-01
Language exerts a powerful influence on our concepts. We review evidence documenting the developmental origins of a precocious link between language and object categories in very young infants. This collection of studies documents a cascading process in which early links between language and cognition provide the foundation for later, more precise ones. We propose that, early in life, language promotes categorization at least in part through its status as a social, communicative signal. But over the first year, infants home in on the referential power of language and, by their second year, begin teasing apart distinct kinds of names (e.g. nouns, adjectives) and their relation to distinct kinds of concepts (e.g. object categories, properties). To complement this proposal, we also relate this evidence to several alternative accounts of language's effect on categorization, appealing to similarity ('labels-as-features'), familiarity ('auditory overshadowing'), and communicative biases ('natural pedagogy').
15 CFR 923.41 - Identification of authorities.
Code of Federal Regulations, 2011 CFR
2011-01-01
... MANAGEMENT COASTAL ZONE MANAGEMENT PROGRAM REGULATIONS Authorities and Organization § 923.41 Identification... exert control over the permissible land uses and water uses within the coastal zone which have a direct... have the authority for the management of the coastal zone. Such authority includes the following powers...
Student Perceptions and Social Comparisons and Performance Expectancy.
ERIC Educational Resources Information Center
Holahan, Carole K.; And Others
Student self-expectations are believed to exert a powerful influence on performance. Student perceptions and social comparisons during transfer students' (N=1362) first semester in a large state university were examined to determine variables that might be related to the formation of student performance expectations. Subjects completed…
Horn, Kyle G; Solomon, Irene C
2014-01-01
Spike-frequency dynamics and spike shape can provide insight into the types of ion channels present in any given neuron and give a sense for the precise response any neuron may have to a given input stimulus. Motoneuron firing frequency over time is especially important due to its direct effect on motor output. Of particular interest is intracellular Ca(2+), which exerts a powerful influence on both firing properties over time and spike shape. In order to better understand the cellular mechanisms for the regulation of intracellular Ca(2+) and their effect on spiking behavior, we have modified a computational model of an HM to include a variety of Ca(2+) handling processes. For the current study, a series of HM models that include Ca(2+) pumps, Na(+)/Ca(2+) exchangers, and a generic exponential decay of excess Ca(2+) were generated. Simulations from these models indicate that although each extrusion mechanism exerts a similar effect on voltage, the firing properties change distinctly with the inclusion of additional Ca(2+)-related mechanisms: BK channels, Ca(2+) buffering, and diffusion of [Ca(2+)]i modeled via a linear diffusion partial differential equation. While an exponential decay of Ca(2+) seems to adequately capture short-term changes in firing frequency seen in biological data, internal diffusion of Ca(2+) appears to be necessary for capturing longer term frequency changes. © 2014 Elsevier B.V. All rights reserved.
Physalis angulata extract exerts anti-inflammatory effects in rats by inhibiting different pathways.
Bastos, G N T; Silveira, A J A; Salgado, C G; Picanço-Diniz, D L W; do Nascimento, J L M
2008-07-23
Physalis angulata is a popular medicine used in Brazil due to its anti-inflammatory effects, but the pharmacological mechanisms underlying these actions remain to be better understood. In the present work, lyophilized aqueous extract from the roots of Physalis angulata Linneu (AEPa) was used to control the inflammatory response induced by the injection of 1% carrageenan into subcutaneous rat's air pouches. Adenosine deaminase (ADA) activity, nitrite level, and prostaglandin E(2) (PGE(2)) level were used to evaluate the action of inflammatory mediators. Tumor growth factor-beta (TGF-beta) level was used as a bioindicator of immunomodulatory response. Rats were injected with vehicle, indomethacin, or AEPa (0.5 mg/kg, 1 mg/kg, and 5 mg/kg i.p.), 1h before carrageenan administration. AEPa at 0.5 mg/kg had no effect. However, 1mg/kg of AEPa showed significant anti-inflammatory effects, decreasing exudate volume, total number of inflammatory cells, ADA activity, nitrite level, and PGE(2) level in 50%, 41%, 20%, 60%, and 41%, respectively. The anti-inflammatory effects of 5 mg/kg AEPa appeared to be more effective than those of 1 mg/kg AEPa (84%, 80%, 43%, 70%, and 75%, respectively). In addition, TGF-beta level was upregulated to 9700 pg/ml after 5mg/kg AEPa, in comparison with 160 pg/ml in the vehicle-treated group, and 137 pg/ml in the indomethacin-treated group. The results indicate that AEPa exerts powerful anti-inflammatory and immunomodulatory activities, interfering with the cyclooxygenase pathway, lymphocyte proliferation, NO, and TGF-beta production.
Tzeng, Wen-Yu; Cherng, Chian-Fang G; Yu, Lung; Wang, Ching-Yi
2017-01-01
The presence of companions renders decreases in cocaine-stimulated dopamine release in the nucleus accumbens and cocaine-induced conditioned place preference (CPP) magnitude. Limbic systems are widely believed to underlie the modulation of accumbal dopamine release and cocaine conditioning. Thus, this study aimed to assess whether intact basolateral nucleus of amygdala (BLA), dorsal hippocampus (DH), and dorsolateral striatum (DLS) is required for the companions-exerted suppressive effect on the cocaine-induced CPP. Three cage mates, serving as companions, were arranged to house with the experimental mice in the cocaine conditioning compartment throughout the cocaine conditioning sessions. Approximately 1week before the conditioning procedure, intracranial ibotenic acid infusions were done in an attempt to cause excitotoxic lesions targeting bilateral BLA, DH and DLS. Albeit their BLA, DH, and DLS lesions, the lesioned mice exhibited comparable cocaine-induced CPP magnitudes compared to the intact and sham lesion controls. Bilateral BLA, but not DH or DLS, lesions abolished the companions-exerted suppressive effect on the cocaine-induced CPP. Intact mice receiving intra-BLA infusion of raclopride, a selective D2 antagonist, 30min prior to the cocaine conditioning did not exhibit the companions-exerted suppressive effect on the cocaine-induced CPP. Intra-BLA infusion of Sch23390, a selective D1 antagonist, did not affect the companions-exerted suppressive effect on the CPP. These results, taken together, prompt us to conclude that the intactness of BLA is required for the companions-exerted suppressive effect on the cocaine-induced CPP. Importantly, activation of D2 receptor in the BLA is required for such suppressive effect on the CPP. Copyright © 2016 Elsevier Inc. All rights reserved.
The effect of grip force, stroke rotation and frequency on discomfort for a torqueing tasks.
Bano, Farheen; Mallick, Zulqernian; Khan, Abid Ali
2015-08-08
Occupational tasks involve awkward upper limb postures, especially movement of forearm with repetitive combined gripping and torqueing exertions, which may lead to development of WMSDs. From the literature survey it was observed that there was a lack of studies focussed on the combined effect of torque and grip exertions on forearm discomfort. The present study was to investigate the effects of grip force, stroke rotation and frequency of exertions on discomfort and Electromyography (EMG) activities of the forearm muscles in a repetitive torqueing task. Twenty-seven male participants volunteered in this study. The participants performed repetitive exertions for a 5 minutes duration for each combination of the different levels of stroke rotation, grip force and frequency of exertions. Three levels of stroke rotation, three levels of grip force and three levels of frequency of exertion were chosen as independent variables. Therefore a 3 × 3 customized factorial design was used for the experiment for each level of grip force. Hence, the study was divided into three groups on the basis of grip force (50N, 70N and 90N). The ANOVA showed that stroke rotation and frequency of exertion were significant on discomfort. Further Students Newmann test (SNK) revealed that discomfort was increased with increasing stroke rotation and frequency of exertion. The multivariate analysis of variances (MANOVA) performed on EMG data instead of ANOVA because EMG activities of five muscles simultaneously were recorded. The Results found that extensor muscles were more fatigued in torqueing with gripping task. It was found that stroke rotation for the torqueing tasks must be kept below 45°. It was concluded that it is important to control stroke rotation to improve performance of repetitive torqueing activity.
Loads produced by a suited subject performing tool tasks without the use of foot restraints
NASA Technical Reports Server (NTRS)
Rajulu, Sudhakar L.; Poliner, Jeffrey; Klute, Glenn K.
1993-01-01
With an increase in the frequency of extravehicular activities (EVA's) aboard the Space Shuttle, NASA is interested in determining the capabilities of suited astronauts while performing manual tasks during an EVA, in particular the situations in which portable foot restraints are not used to stabilize the astronauts. Efforts were made to document the forces that are transmitted to spacecraft while pushing and pulling an object as well as while operating a standard wrench and an automatic power tool. The six subjects studied aboard the KC-135 reduced gravity aircraft were asked to exert a maximum torque and to maintain a constant level of torque with a wrench, to push and pull an EVA handrail, and to operate a Hubble Space Telescope (HST) power tool. The results give an estimate of the forces and moments that an operator will transmit to the handrail as well as to the supporting structure. In general, it was more effective to use the tool inwardly toward the body rather than away from the body. There were no differences in terms of strength capabilities between right and left hands. The power tool was difficult to use. It is suggested that ergonomic redesigning of the power tool may increase the efficiency of power tool use.
An Experimental Study on the Darrieus-Savonius Turbine for the Tidal Current Power Generation
NASA Astrophysics Data System (ADS)
Kyozuka, Yusaku
The Darrieus turbine is popular for tidal current power generation in Japan. It is simple in structure with straight wings rotating around a vertical axis, so that it has no directionality against the motion of tidal flow which changes its direction twice a day. However, there is one defect in the Darrieus turbine; its small starting torque. Once it stops, a Darrieus turbine is hard to re-start until a fairly fast current is exerted on it. To improve the starting torque of the Darrieus turbine used for tidal power generation, a hybrid turbine, composed of a Darrieus turbine and a Savonius rotor is proposed. Hydrodynamic characteristics of a semi-circular section used for the Savonius bucket were measured in a wind tunnel. The torque of a two bucket Savonius rotor was measured in a circulating water channel, where four different configurations of the bucket were compared. A combined Darrieus and Savonius turbine was tested in the circulating water channel, where the effect of the attaching angle between Darrieus wing and Savonius rotor was studied. Finally, power generation experiments using a 48 pole electric generator were conducted in a towing tank and the power coefficients were compared with the results of experiments obtained in the circulating water channel.
Orava, S; Puranen, J
1978-01-01
Over a period of three years 829 cases of greater than or equal to 16-year-old athlete exertion injuries and syndromes were collected. There were 75 women and 754 men in the series. About 90% of the athletes had been training regularly for more than two years, and 75% of them trained 6 times a week or more. Approximately 52% of the injuries occurred in track and field athletics, about 17% in ball events, 13.6% in skiing, 7.4% in orienteering, and 4.7% in power events. Other sports were associated with fewer exertion injuries. 28.7% of the conditions occurred in the knee, 17% in the ankle, foot and heel, 14.8% in the leg, 8.2% in the back and trunk, 8.1% in the thigh, 7.4% in the achilles tendon. The rest were in the shoulder, neck and upper extremities. In 92% of the patients conservative treatment and rest were used. Only 8% of the cases were treated surgically.
Out of Sight, out of Mind: The Attentional Blink Can Eliminate Synaesthetic Colours
ERIC Educational Resources Information Center
Rich, Anina N.; Mattingley, Jason B.
2010-01-01
Mechanisms of selective attention exert a powerful influence on visual perception. We examined whether attentional selection is necessary for generation of the vivid colours experienced by individuals with grapheme-colour synaesthesia. Twelve synaesthetes and matched controls viewed rapid serial displays of nonsense characters within which were…
Knowledge Organization and the Acquisition of Procedural Expertise.
1987-10-01
NO NO ACCESSION NO 11i TITLE (InCludf S#cufltY Cissjf)CAtl~on) KOWLEDGE ORGANIZATION AND THE ACQUISITION OF PROCEDURAL EXPERTISE 12 PERSONAL AUTIR...explanatory material strongly influences the knowledge representation of the learner which, in turn, exerts a powerful influence over the degree to which
The Washback of the TOEFL iBT in Vietnam
ERIC Educational Resources Information Center
Barnes, Melissa
2016-01-01
Washback, or the influence of testing on teaching and learning, has received considerable attention in language testing research over the past twenty years. It is widely argued that testing, particularly high-stakes testing, exerts a powerful influence, whether intended or unintended, positive or negative, on both teachers and learners. This…
Linking Language and Categorization in Infancy
ERIC Educational Resources Information Center
Ferguson, Brock; Waxman, Sandra
2017-01-01
Language exerts a powerful influence on our concepts. We review evidence documenting the developmental origins of a precocious link between language and object categories in very young infants. This collection of studies documents a cascading process in which early links between language and cognition provide the foundation for later, more precise…
Assessing Graduate Teaching Assistants' Beliefs and Practices
ERIC Educational Resources Information Center
Douglas, Jennifer; Powell, Darcey N.; Rouamba, Nathalie H.
2016-01-01
Graduate teaching assistants (GTAs) play a crucial role in North American colleges. At a mid-Atlantic, land grant institution, GTAs instruct 34,000 undergraduates per semester. Given this scope, GTAs exert a powerful influence on undergraduate learning, yet little is known about their teaching beliefs in relation to their classroom practices. This…
Media/Visual Literacy Art Education: Cigarette Ad Deconstruction
ERIC Educational Resources Information Center
Chung, Sheng Kuan
2005-01-01
Visual images are not simply embodiments of social reality; they are indeed ideological sites embedded with powerful discursive sociopolitical meanings that exert strong influences on the ways in which people live their lives. The author of this paper describes the Ad-Deconstruction Project, which challenged students to integrate aesthetic…
The Self-Efficacy Scale: A Construct Validity Study.
ERIC Educational Resources Information Center
Sherer, Mark; Adams, Carol
Self-efficacy is defined as the belief that one can successfully perform a behavior. Self-efficacy theory asserts that self-efficacy expectancies exert powerful influence on behavior and behavior change. The Self-efficacy Scale, which was developed to assess generalized self-efficacy expectations, consists of two subscales: general self-efficacy…
Mutual powerlessness in client participation practices in mental health care
Broer, Tineke; Nieboer, Anna P.; Bal, Roland
2012-01-01
Abstract Background Client participation has become a dominant policy goal in many countries including the Netherlands and is a topic much discussed in the literature. The success of client participation is usually measured in terms of the extent to which clients have a say in the participation process. Many articles have concluded that client participation is limited; professionals often still control the participation process and outcomes. Objective The objective of this study is to gain insight into (i) the practice of client participation within a quality improvement collaborative in mental health care and (ii) the consequences of a Foucauldian conceptualization of power in analysing practices of client participation. Design We used an ethnographic design consisting of observations of national events and improvement team meetings and interviews with the collaborative’s team members and programme managers. Results Contrary to many studies on client participation, we found both clients and service providers frequently felt powerless in its practice. Professionals and clients alike struggled with the contributions clients could make to the improvement processes and what functions they should fulfil. Moreover, professionals did not want to exert power upon clients, but ironically just for that reason sometimes struggled with shaping practices of client participation. This mutual powerlessness (partly) disappeared when clients helped to determine and execute specific improvement actions instead of participating in improvement teams. Conclusion Recognizing that power is inescapable might allow for a more substantive discussion concerning the consequences that power arrangements produce, rather than looking at who is exerting how much power. PMID:22390793
Cirulli, Francesca; Berry, Alessandra; Bonsignore, Luca Tommaso; Capone, Francesca; D'Andrea, Ivana; Aloe, Luigi; Branchi, Igor; Alleva, Enrico
2010-05-01
During the early post-natal phases the brain is experience-seeking and provided by a considerable plasticity which allows a fine tuning between the external environment and the developing organism. Since the early work of Seymour Levine, an impressive amount of research has clearly shown that stressful experiences exert powerful effects on the brain and body development. These effects can last throughout the entire life span influencing brain function and increasing the risk for depression and anxiety disorders. The mechanisms underlying the effects of early stress on the developing organism have been widely studied in rodents through experimental manipulations of the post-natal environment, such as handling, which have been shown to exert important effects on the emotional phenotype and the response to stress. In the present paper we review the relevant literature and present some original data indicating that, compared to handling, which imposes an external manipulation on the mother-infant relationship, social enrichment, in the form of communal rearing, in mice has very profound effects on animal's emotionality and the response to stress. These effects are also accompanied by important changes in central levels of brain-derived neurotrophic factor. The present data indicate that communal rearing has more pervasive effects than handling, strengthening previous data suggesting that it is a good animal model of reduced susceptibility to depression-like behavior. Overall, the availability of ever more sophisticated animal models represents a fundamental tool to translate basic research data into appropriate interventions for humans raised under traumatic or impoverished situations. (c) 2010 Elsevier Ltd. All rights reserved.
Saraulli, Daniele; Costanzi, Marco; Mastrorilli, Valentina; Farioli-Vecchioli, Stefano
2017-01-01
Background The rapid lengthening of life expectancy has raised the problem of providing social programs to counteract the age-related cognitive decline in a growing number of older people. Physical activity stands among the most promising interventions aimed at brain wellbeing, because of its effective neuroprotective action and low social cost. The purpose of this review is to describe the neuroprotective role exerted by physical activity in different life stages. In particular, we focus on adult neurogenesis, a process which has proved being highly responsive to physical exercise and may represent a major factor of brain health over the lifespan. Methods The most recent literature related to the subject has been reviewed. The text has been divided into three main sections, addressing the effects of physical exercise during childhood/adolescence, adulthood and aging, respectively. For each one, the most relevant studies, carried out on both human participants and rodent models, have been described. Results The data reviewed converge in indicating that physical activity exerts a positive effect on brain functioning throughout the lifespan. However, uncertainty remains about the magnitude of the effect and its biological underpinnings. Cellular and synaptic plasticity provided by adult neurogenesis are highly probable mediators, but the mechanism for their action has yet to be conclusively established. Conclusion Despite alternative mechanisms of action are currently debated, age-appropriate physical activity programs may constitute a large-scale, relatively inexpensive and powerful approach to dampen the individual and social impact of age-related cognitive decline. PMID:27000776
Rayner, Brian
2004-03-01
Hypertension in combination with clinically overt diabetes mellitus is recognized as a particularly powerful combination of risk factors that greatly increases cardiovascular vulnerability. There is also evidence that presumed pre-diabetic conditions such as insulin resistance, hyperinsulinaemia and compensatory hyperglycaemia may amplify overall cardiovascular risk in patients with hypertension, especially when encountered as part of the condition known as metabolic syndrome X (Reaven's syndrome). The long-term benefits of antihypertensive therapy may be compromised if these drugs exert adverse effects on metabolic parameters such as insulin sensitivity, or if they promote a transition from pre-diabetes to overt diabetes. Class differences in the effects of antihypertensives on metabolic indices may therefore be an important consideration when choosing treatment for patients who exhibit these characteristics. Experience from clinical trials suggests that drugs that target the renin-angiotensin system may have metabolic advantages over drugs such as beta-blockers and diuretics, but this conclusion has not been proved definitively. Moxonidine, which selectively targets imidazoline type-1 receptors in the sympathetic vasomotor centres of the rostral-ventrolateral medulla, is an effective antihypertensive and has been reported to exert favourable metabolic effects in preclinical and clinical studies. The MARRIAGE study (Moxonidine And Ramipril Regarding Insulin And Glucose Evaluation) will extend these preliminary observations by comparing the effects of moxonidine and the ACE inhibitor ramipril--and the combination of both drugs--on metabolic and haemodynamic parameters in patients with hypertension and impaired fasting glycaemia. A description is provided of the design and conduct of MARRIAGE.
Hohenauer, Erich; Clarys, Peter; Baeyens, Jean-Pierre; Clijsen, Ron
2016-01-01
The purpose of this controlled trial was to investigate the effects of a single local cryotherapy session on the recovery characteristics over a period of 72 hours. Twenty-two young and healthy female (n=17; mean age: 21.9±1.1 years) and male (n=5;mean age: 25.4±2.8 years) adults participated in this study. Following an exhaustive jump protocol (3×30 countermovement jumps), half of the participants received either a single local cryotherapy application (+8°C) or a single local thermoneutral application (+32°C) of 20-minute duration using two thigh cuffs. Subjective measures of recovery (delayed-onset muscle soreness and ratings of perceived exertion) and objective measures of recovery (vertical jump performance and peak power output) were assessed immediately following the postexercise applications (0 hours) and at 24 hours, 48 hours, and 72 hours after the jump protocol. Local cryotherapy failed to significantly affect any subjective recovery variable during the 72-hour recovery period (P>0.05). After 72 hours, the ratings of perceived exertion were significantly lower in the thermoneutral group compared to that in the cryotherapy group (P=0.002). No significant differences were observed between the cryotherapy and the thermoneutral groups with respect to any of the objective recovery variables. In this experimental study, a 20-minute cryotherapy cuff application failed to demonstrate a positive effect on any objective measures of recovery. The effects of local thermoneutral application on subjective recovery characteristics were superior when compared to the effects of local cryotherapy application at 72 hours postapplication. PMID:27579000
Hohenauer, Erich; Clarys, Peter; Baeyens, Jean-Pierre; Clijsen, Ron
2016-01-01
The purpose of this controlled trial was to investigate the effects of a single local cryotherapy session on the recovery characteristics over a period of 72 hours. Twenty-two young and healthy female (n=17; mean age: 21.9±1.1 years) and male (n=5;mean age: 25.4±2.8 years) adults participated in this study. Following an exhaustive jump protocol (3×30 countermovement jumps), half of the participants received either a single local cryotherapy application (+8°C) or a single local thermoneutral application (+32°C) of 20-minute duration using two thigh cuffs. Subjective measures of recovery (delayed-onset muscle soreness and ratings of perceived exertion) and objective measures of recovery (vertical jump performance and peak power output) were assessed immediately following the postexercise applications (0 hours) and at 24 hours, 48 hours, and 72 hours after the jump protocol. Local cryotherapy failed to significantly affect any subjective recovery variable during the 72-hour recovery period (P>0.05). After 72 hours, the ratings of perceived exertion were significantly lower in the thermoneutral group compared to that in the cryotherapy group (P=0.002). No significant differences were observed between the cryotherapy and the thermoneutral groups with respect to any of the objective recovery variables. In this experimental study, a 20-minute cryotherapy cuff application failed to demonstrate a positive effect on any objective measures of recovery. The effects of local thermoneutral application on subjective recovery characteristics were superior when compared to the effects of local cryotherapy application at 72 hours postapplication.
Fontana, Luigi
2009-01-01
Acute inflammation is usually a self-limited life preserving response, triggered by pathogens and/or traumatic injuries. This transient response normally leads to removal of harmful agents and to healing of the damaged tissues. In contrast, unchecked or chronic inflammation can lead to persistent tissue and organ damage by activated leukocytes, cytokines, or collagen deposition. Excessive energy intake and adiposity cause systemic inflammation, whereas calorie restriction without malnutrition exerts a potent anti-inflammatory effect. As individuals accumulate fat and their adipocytes enlarge, adipose tissue undergoes molecular and cellular alterations, macrophages accumulate, and inflammation ensues. Overweight/obese subjects have significantly higher plasma concentrations of C-reactive protein and several cytokines, including IL-6, IL-8, IL-18, and TNF-alpha. Experimental animals on a chronic CR regimen, instead, have low levels of circulating inflammatory cytokines, low blood lymphocyte levels, reduced production of inflammatory cytokines by the white blood cells in response to stimulation, and cortisol levels in the high normal range. Recent data demonstrate that CR exerts a powerful anti-inflammatory effect also in non-human primates and humans. Multiple metabolic and neuroendocrine mechanisms are responsible for the CR-mediated anti-inflammatory effects, including reduced adiposity and secretion of pro-inflammatory adipokines, enhanced glucocorticoid production, reduced plasma glucose and advanced glycation end-product concentrations, increased parasympathetic tone, and increased ghrelin production. Measuring tissue specific effects of CR using genomic, proteomic and metabolomic techniques in humans will foster the understanding of the complex biological processes involved in the anti-inflammatory and anti-aging effects of CR. PMID:18502597
2013-01-01
Background This study compared the effects of ingesting water (W), a flavored carbohydrate-electrolyte (CE) or a flavored non-caloric electrolyte (NCE) beverage on mood, ratings of perceived exertion (RPE), and sprint power during cycling in recreational exercisers. Methods Men (n = 23) and women (n = 13) consumed a 24–h standardized diet and reported 2–4 h post-prandial for all test sessions. After a familiarization session, participants completed 50 min of stationary cycling in a warm environment (wet bulb globe temperature = 25.0°C) at ~ 60-65% of heart rate reserve (146 ± 4 bpm) interspersed with 5 rest periods of 2 min each. During exercise, participants consumed W, CE, or NCE, served in a counterbalanced cross-over design. Beverage volume was served in 3 aliquots equaling each individual’s sweat losses (mean 847 ± 368 mL) during the familiarization session. Profiles of Mood States questionnaires (POMS) were administered and blood glucose levels were determined pre- and post- sub-maximal cycling. Following sub-maximal exercise, participants completed 3 30–s Wingate anaerobic tests (WAnT) with 2.5 min rest between tests to assess performance. Results Blood glucose was higher (p < 0.05) after 50 min of submaximal cycling just prior to the WAnT for CE (6.1 ± 1.7 mmol/L) compared to W (4.9 ± 1.5 mmol/L) and NCE (4.6 ± 1.2 mmol/L). Nonetheless, there were no differences among treatments in peak (642 ± 153, 635 ± 143, 650 ± 141 watts for W, NCE, and CE, respectively; p = 0.44) or mean (455 ± 100, 458 ± 95, 454 ± 95 watts for W, NCE, and CE, respectively; p = 0.62) power for the first WAnT or mean (414 ± 92, 425 ± 85, 423 ± 82 watts, respectively; p = 0.13) power output averaged across all 3 WAnT. Likewise, RPE during submaximal exercise, session RPE, and fatigue and vigor assessed by POMS did not differ among beverage treatments (p > 0.05). Conclusions Carbohydrate ingestion consumed by recreational exercisers during a 1–h, moderate-intensity aerobic workout did not alter mood or perceived exertion, nor did it affect subsequent anaerobic performance under the conditions of this study. Drinking caloric sport beverages does not benefit recreational exercisers in a non-fasted state. PMID:23347391
Savitha, D; Sejil, T V; Rao, Shwetha; Roshan, C J; Roshan, C J
2013-01-01
The purpose of the study was to investigate the effect of vocal and instrumental music on various physiological parameters during submaximal exercise. Each subject underwent three sessions of exercise protocol without music, with vocal music, and instrumental versions of same piece of music. The protocol consisted of 10 min treadmill exercise at 70% HR(max) and 20 min of recovery. Minute to minute heart rate and breath by breath recording of respiratory parameters, rate of energy expenditure and perceived exertion levels were measured. Music, irrespective of the presence or absence of lyrics, enabled the subjects to exercise at a significantly lower heart rate and oxygen consumption, reduced the metabolic cost and perceived exertion levels of exercise (P < 0.05). There was faster recovery of systolic and diastolic blood pressures and exertion levels during the post exercise period. Music having a relaxant effect could have probably increased the parasympathetic activation leading to these effects.
Ischemic Preconditioning Enhances Performance and Erythrocyte Deformability of Responders.
Tomschi, Fabian; Niemann, David; Bloch, Wilhelm; Predel, Hans-Georg; Grau, Marijke
2018-06-08
This pilot study aimed to evaluate the differential effects of a remote ischemic preconditioning (rIPC) manoeuvre on performance and red blood cell (RBC) deformability compared to a sham control and a placebo setting. Ten male subjects performed three test settings in a single-blind, crossover, and randomized control design. All settings started with 20 min of rest and were followed by 4 cycles of occlusion/reperfusion consisting of 5 min each. During rIPC and placebo, the cuff pressure was inflated to 200 mmHg and 120 mmHg, respectively. During the sham control setting, 10 mmHg pressure was applied. All tests were followed by a cycle exercise with lactate diagnostics. Power at 2 and 4 mmol/l lactate thresholds were calculated. RBC deformability was measured before and after the respective manoeuvre. Results showed that no effect resulted from any manoeuvre on performance values or RBC deformability. But 6 subjects showed a higher power at the 2 mmol/l threshold, and 5 subjects exerted higher power at the 4 mmol/l threshold when the rIPC manoeuvre preceded the exercise. In these responsive subjects, RBC deformability also improved. Hence, rIPC effects are much influenced by the subjects' responsiveness, and improved RBC deformability might contribute to enhanced performance in responsive subjects. © Georg Thieme Verlag KG Stuttgart · New York.
NASA Astrophysics Data System (ADS)
Huang, Lei; Wu, Shengnan; Xing, Da
2011-03-01
Glycogen synthase kinase-3β (GSK-3β) is a critical activator of cell apoptosis induced by a diverse array of insults. However, the effects of GSK-3β on the human lung adenocarcinoma cell (ASTC-a-1) apoptosis induced by high fluence low-power laser irradiation (HF-LPLI) are not clear. Here, we showed that GSK-3β was constantly translocated from cytoplasm to nucleus and activated during HF-LPLI-induced cell apoptosis. In addition, we found that co-overexpression of YFP-GSK-3β and CFP-Bax in ASTC-a-1 cells accelerated both Bax translocations to mitochondria and cell apoptosis, compared to the cells expressed CFP-Bax only under HF-LPLI treatment, indicating that GSK-3β facilitated ASTC-a-1 cells apoptosis through acceleration mitochondrial translocation of Bax. Our results demonstrate that GSK-3β exerts some of its pro-apoptotic effects in ASTC-a-1 cells by regulating the mitochondrial localization of Bax, a key component of the intrinsic apoptotic cascade.
The Influence of Compression Stocking on Jumping Performance of Athlete
NASA Astrophysics Data System (ADS)
Salleh, M. N.; Lazim, H. M.; Lamsali, H.; Salleh, A. F.
2018-05-01
Evidence of compression stocking effectiveness are mixed, with some researchers suggests that the stocking can enhance performance while others dispute the finding. One of the factors that are thought to cause the mixed results is level of pressure used in their studies. This research had organized a test on fourteen athletes. Their body was scanned and a customized compression stocking which can exert pressure correspond to the intended one was developed. An experiment was conducted to measure the effect of wearing compression stocking on jumping performance. The results show mixed outcomes. For the female athlete, there is a significant difference between wearing and not wearing compression stocking (p<0.05) on knee power. However, there is no significant difference for male athletes whether wearing or not.
The return on the blueback salmon to the Columbia River
Fisher, Frederick S.
1948-01-01
THE year 1941 was a crucial one for the blueback salmon of the Columbia River. During that year, one brood came closer to extinction than was realized by more than a few individuals. The immediate causes were not overfishing, hydroelectric power development, or irrigation—although these factors continued to exert their long-standing effects. The direct causes can be attributed to an “act of God” plus—in large measure--lack of knowledge concerning the basic principles of effective artificial propagation. With the security and assurance provided by subsequent developments, those concerned with the Columbia River blueback salmon may be interested in a brief recapitulation of events that transpired during the early 1940s. This particular piece of fishery history bears upon the problems of the immediate future on the Columbia River.
Using the prisms of gender and rank to interpret research collaboration power dynamics.
Gaughan, Monica; Bozeman, Barry
2016-08-01
Collaboration is central to modern scientific inquiry, and increasingly important to the professional experiences of academic scientists. While the effects of collaboration have been widely studied, much less is understood about the motivations to collaborate and collaboration dynamics that generate scientific outcomes. A particular interest of this study is to understand how collaboration experiences differ between women and men, and the attributions used to explain these differences. We use a multi-method study of university Science, Technology, Engineering, and Mathematics faculty research collaborators. We employ 177 anonymous open-ended responses to a web-based survey, and 60 semi-structured interviews of academic scientists in US research universities. We find similarities and differences in collaborative activity between men and women. Open-ended qualitative textual analysis suggests that some of these differences are attributed to power dynamics - both general ones related to differences in organizational status, and in power dynamics related specifically to gender. In analysis of semi-structured interviews, we find that both status and gender were used as interpretive frames for collaborative behavior, with more emphasis placed on status than gender differences. Overall, the findings support that gender structures some part of the collaborative experience, but that status hierarchy exerts more clear effects.
Selective effects of weight and inertia on maximum lifting.
Leontijevic, B; Pazin, N; Kukolj, M; Ugarkovic, D; Jaric, S
2013-03-01
A novel loading method (loading ranged from 20% to 80% of 1RM) was applied to explore the selective effects of externally added simulated weight (exerted by stretched rubber bands pulling downward), weight+inertia (external weights added), and inertia (covariation of the weights and the rubber bands pulling upward) on maximum bench press throws. 14 skilled participants revealed a load associated decrease in peak velocity that was the least associated with an increase in weight (42%) and the most associated with weight+inertia (66%). However, the peak lifting force increased markedly with an increase in both weight (151%) and weight+inertia (160%), but not with inertia (13%). As a consequence, the peak power output increased most with weight (59%), weight+inertia revealed a maximum at intermediate loads (23%), while inertia was associated with a gradual decrease in the peak power output (42%). The obtained findings could be of importance for our understanding of mechanical properties of human muscular system when acting against different types of external resistance. Regarding the possible application in standard athletic training and rehabilitation procedures, the results speak in favor of applying extended elastic bands which provide higher movement velocity and muscle power output than the usually applied weights. © Georg Thieme Verlag KG Stuttgart · New York.
Plasma sweeper to control the coupling of RF power to a magnetically confined plasma
Motley, Robert W.; Glanz, James
1985-01-01
A device for coupling RF power (a plasma sweeper) from a phased waveguide array for introducing RF power to a plasma having a magnetic field associated therewith comprises at least one electrode positioned near the plasma and near the phased waveguide array; and a potential source coupled to the electrode for generating a static electric field at the electrode directed into the plasma and having a component substantially perpendicular to the plasma magnetic field such that a non-zero vector cross-product of the electric and magnetic fields exerts a force on the plasma causing the plasma to drift.
Hydrocortisone Infusion Exerts Dose- and Sex-Dependent Effects on Attention to Emotional Stimuli
ERIC Educational Resources Information Center
Breitberg, Alaina; Drevets, Wayne C.; Wood, Suzanne E.; Mah, Linda; Schulkin, Jay; Sahakian, Barbara J.; Erickson, Kristine
2013-01-01
Glucocorticoid administration has been shown to exert complex effects on cognitive and emotional processing. In the current study we investigated the effects of glucocorticoid administration on attention towards emotional words, using an Affective Go/No-go task on which healthy humans have shown an attentional bias towards positive as compared to…
Flower power: its association with bee power and floral functional morphology in papilionate legumes
Córdoba, Silvina A.; Cocucci, Andrea A.
2011-01-01
Background and Aims A test was made of the hypothesis that papilionate legume flowers filter pollinators according to their ability to exert strength to open flowers to access rewards. In addition, interactions with pollen vectors were expected to explain the structural complexity of the architecture of these flowers since operative flower strength may be determined by a combination of morphological traits which form part of an intrafloral functional module. Methods Six papilionate species were studied: Collaea argentina, Desmodium uncinatum, Galactia latisiliqua, Lathyrus odoratus, Spartium junceum and Tipuana tipu. Measurements were made of the strength needed to open keels and the strength that pollinators were capable of exerting. Morphological traits of all petals were also measured to determine which of them could be either mutually correlated or correlated with operative strength and moment of strength and participated in a functional module. Key Results It was observed that pollinators were capable in all cases of exerting forces higher and often several times higher than that needed to access floral rewards, and no association could be detected between floral operative strength and strength exerted by the corresponding pollinators. On the other hand, strong and significant correlations were found among morphometric traits and, of these, with operative strength and moment. This was particularly evident among traits of the keel and the wings, presumably involved in the functioning of the floral moveable mechanism. Conclusions Though visitors are often many times stronger than the operative strength of the flowers they pollinate, exceptionally weak bees such as Apis mellifera cannot open the strongest flowers. On the other hand, strong correlations among certain petal morphometric traits (particularly between the keel and wings) give support to the idea that an intrafloral module is associated with the functioning of the mechanism of these legume flowers. In addition, the highly significant correlations found across petals support the view of functional phenotypic integration transcending the ontogenetic organization of flower structure. PMID:21821623
Influence of upper-body external loading on anaerobic exercise performance.
Inacio, Mario; Dipietro, Loretta; Visek, Amanda J; Miller, Todd A
2011-04-01
The purpose of this study was to assess the threshold where simulated adipose tissue weight gain significantly affects performance in common anaerobic tasks and determine whether differences exist between men and women. Forty-six subjects (men = 21; women = 25) were tested for vertical jump, 20- and 40-yd dash, and 20-yd shuttle tests under 6 different loading conditions (0, 2, 4, 6, 8, and 10% of added body weight). Results were compared to each subject's baseline values (0% loading condition). Results demonstrate significant decrements in performance, starting at the 2% loading condition, for both genders, in every performance test (p < 0.05). On average, subjects jumped 4.91 ± 0.29 to 9.83 ± 0.30 cm less, increased agility test times from 5.49 ± 0.56 to 5.86 ± 0.61 seconds, and increased sprint times from 7.80 ± 0.96 to 8.39 ± 1.07 seconds (2-10%, respectively; p < 0.05). When lower-body power was corrected for total body mass, men exerted significantly more power than women did in every loading condition. Conversely, when lower-body power was corrected for lean body mass, men exerted significantly more power than did women only at the 2% loading condition. This study demonstrates that for the specific anaerobic performance tests performed, increases in external loading as low as 2% of body weight results in significant decreases in performance. Moreover, for these specific tests, men and women tend to express the same threshold in performance decrements.
Liu, Han-Bo; Gao, Wei-Wei; Tangadanchu, Vijai Kumar Reddy; Zhou, Cheng-He; Geng, Rong-Xia
2018-01-01
A series of novel aminopyrimidinyl benzimidazoles as potentially antimicrobial agents were designed, synthesized and characterized by IR, NMR and HRMS spectra. The biological evaluation in vitro revealed that some of the target compounds exerted good antibacterial and antifungal activity in comparison with the reference drugs. Noticeably, compound 7d could effectively inhibit the growth of A. flavus, E. coli DH52 and MRSA with MIC values of 1, 1 and 8 μg/mL, respectively. Further studies revealed that pyrimidine derivative 7d could exhibit bactericidal mode of action against both Gram positive (S. aureus and MRSA) and Gram negative (P. aeruginosa) bacteria. The active molecule 7d showed low cell toxicity and did not obviously trigger the development of resistance in bacteria even after 16 passages. Furthermore, compound 7d was able to beneficially regulate reactive oxygen species (ROS) generation for an excellent safety profile. Molecular docking study revealed that compound 7d could bind with DNA gyrase by the formation of hydrogen bonds. The preliminary exploration for antimicrobial mechanism disclosed that compound 7d could effectively intercalate into calf thymus DNA to form a steady supramolecular complex, which might further block DNA replication to exert the powerful bioactivities. The binding investigation of compound 7d with human serum albumins (HSA) revealed that this molecule could be effectively transported by HSA. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
The "White Glove Pulpit": A History of Policy Influence by First Ladies.
ERIC Educational Resources Information Center
Watson, Robert P.
2001-01-01
Focuses on the public policy influence exerted by the early first ladies, whose endeavors comprise a "White Glove Pulpit," a feminine means of asserting power in the realm of strict gender confines. Discusses four roles (spouse and partner, hostess, advocate, and public figure and campaigner) through which the First Ladies influenced…
Project-Based Learning and Rubrics in the Teaching of Power Supplies and Photovoltaic Electricity
ERIC Educational Resources Information Center
Martinez, F.; Herrero, L. C.; de Pablo, S.
2011-01-01
Project-based learning (PBL) and cooperative learning are, in various aspects, very superior education methodologies compared to other traditional ones. They are highly appropriate methodologies for elective courses, as they exert a strong attraction on the students, quite apart from their educational advantages. This paper describes how PBL and…
Chen, Gang; Glen, Daniel R.; Saad, Ziad S.; Hamilton, J. Paul; Thomason, Moriah E.; Gotlib, Ian H.; Cox, Robert W.
2011-01-01
Vector autoregression (VAR) and structural equation modeling (SEM) are two popular brain-network modeling tools. VAR, which is a data-driven approach, assumes that connected regions exert time-lagged influences on one another. In contrast, the hypothesis-driven SEM is used to validate an existing connectivity model where connected regions have contemporaneous interactions among them. We present the two models in detail and discuss their applicability to FMRI data, and interpretational limits. We also propose a unified approach that models both lagged and contemporaneous effects. The unifying model, structural vector autoregression (SVAR), may improve statistical and explanatory power, and avoids some prevalent pitfalls that can occur when VAR and SEM are utilized separately. PMID:21975109
Delmas, Virginie; Bonnet, Xavier; Girondot, Marc; Prévot-Julliard, Anne-Caroline
2008-01-01
Environmental conditions within the nest, notably temperature and moisture of substrate, exert a powerful influence during embryogenesis in oviparous reptiles. The influence of fluctuating nest temperatures has been experimentally examined in different reptile species; however, similar experiments using moisture as the key variable are lacking. In this article, we examine the effect of various substrate moisture regimes during incubation on different traits (egg mass, incubation length, and hatchling mass) in a chelonian species with flexible-shelled eggs, the red-eared slider turtle (Trachemys scripta elegans). Our results show that the rate of water uptake by the eggs was higher in wet than in dry substrate and varied across development. More important, during the first third of development, the egg mass changes were relatively independent of the soil moisture level; they became very sensitive to moisture levels during the other two-thirds. Moreover, hydric conditions exerted a strong influence on the eggs' long-term sensitivity to the moisture of the substrate. Even short-term episodes of high or low levels of moisture modified permanently their water sensitivity, notably through modification of eggshell shape and volume, and in turn entailed significant effects on hatchling mass (and hence offspring quality). Such complex influences of fluctuating moisture levels at various incubation stages on hatchling phenotype better reflect the natural situation, compared to experiments based on stable, albeit different, moisture levels.
Enhancing Short-Term Recovery After High-Intensity Anaerobic Exercise.
Al-Nawaiseh, Ali M; Pritchett, Robert C; Bishop, Philip A
2016-02-01
This study examined the effects of antioxidant vitamins, ibuprofen, cold water submersion, and whey protein administered simultaneously on short-term recovery. Competitive athletes (n = 22) performed the protocol in 2 occasions (treatment and control) separated by 15 days in counterbalanced crossover design. Each occasion consisted of morning and afternoon sessions (AM and PM). In each session, participants performed 2 bouts of high-intensity anaerobic cycling separated by 30 minutes of rest. Each bout consisted of 3 Wingate tests (3 × 30-second Wingate tests) with 3 minutes of active recovery in between. Power output, rated perceived exertion (RPE), and pain scores were averaged and compared between the 2 sessions (AM vs. PM) and between the treatment vs. control (4 bouts). Creatine kinase (CK) levels were also measured 24 hours after the AM bout. Power output, CK, muscle soreness, and RPE were measured as recovery indices. Creatine kinase increased (p < 0.001) in both treatment and control 24 hours after the AM session. Performance results in the PM session for treatment/control were 832.5 ± 198.7/813.3 ± 187.6 W for peak power (PP), and 497.85 ± 120.7/486.1 ± 115 W for mean power (MP). Treatment was effective in maintaining MP (p = 0.034) in the PM sessions, but there was no significant effect of treatment on PP (p = 0.193), CK (p = 0.08), pain (p = 0.12), or RPE (p = 0.45). Treatment was helpful in protecting performance, but this was apparently not due to reduced muscle soreness or damage.
Wise, P M; Dubal, D B; Wilson, M E; Rau, S W; Böttner, M; Rosewell, K L
2001-11-01
We have shown that 17beta-estradiol exerts profound protective effects against stroke-like ischemic injury in female rats. These effects are evident using physiological levels of estradiol replacement in ovariectomized rats and require hormone treatment prior to the time of injury. The protective actions of estradiol appear to be most prominent in the cerebral cortex, where cell death is not apparent until at least 4 h after the initiation of ischemic injury and where cell death is thought to be apoptotic in nature. Middle-aged rats remain equally responsive to the protective actions of estradiol. The maintenance of responsiveness of the cerebral cortex to the neuroprotective actions of estradiol was unexpected since responsiveness of the hypothalamus to estradiol decreases dramatically by the time animals are middle-aged. We believe that the protective actions of estradiol require the estrogen receptor-alpha, since estradiol does not protect in estrogen receptor-alpha knockout mice. We have also implemented a method of culturing cerebral cortical explants to assess the protective effects of estradiol in vitro. This model exhibits remarkable parallelisms with our in vivo model of brain injury. We have found that 17beta-estradiol decreases the extent of cell death and that this protective effect requires hormone pretreatment. Finally, 17alpha-estradiol, which does not interact effectively with the estrogen receptor, does not protect; and addition of ICI 182,780, an estrogen receptor antagonist, blocks the protective actions of estradiol. We have begun to explore the molecular and cellular mechanisms of estradiol-mediated protection. In summary, our findings demonstrate that estradiol exerts powerful protective effects both in vivo and in vitro and suggest that these actions are mediated by estrogen receptors.
Effects of differentiated music on cycling time trial.
Lim, H B T; Atkinson, G; Karageorghis, C I; Eubank, M R; Eubank, M M
2009-06-01
The aim of this study was to investigate the effects of music introduced and removed during a 10-km cycling time trial with reference to Rejeski's parallel processing theory and Karageorghis, Terry and Lane's conceptual framework for the prediction of responses to asynchronous music during sub-maximal exercise. A range of performance variables, ratings of perceived exertion, positive affect, negative affect, and blood lactate were assessed. Eleven males (mean age=24.9, s=6.1 years) completed a 10-km time trial under three conditions; no music, music played initially then removed between 5-10 km, and music played between 5-10 km only. Variables of time, power, cadence, speed, RPE, blood lactate, positive and negative affect were analysed using a ConditionxDistance ANOVA. There was no significant main effect for music conditions for the performance variables, perceived exertion, blood lactate, and affect (p>0.05). Nevertheless, a significant interaction effect for ConditionxDistance was found for cycling speed, with participants cycling 1-1.25 km/h faster at the start of the music introduced time trial than in both the music removed and no music time trials (p<0.05). The results indicate that performance and affect during a 10 km time trial are influenced by the introduction and/or removal of music during exercise and this finding can be used to extend current theory as it does not specifically address the periodic use music. The fact that participants exercised harder when they expected music to be introduced at a later stage illustrates the behavioural influences that music can engender during self-paced exercise.
Godoy, Juan A; Lindsay, Carolina B; Quintanilla, Rodrigo A; Carvajal, Francisco J; Cerpa, Waldo; Inestrosa, Nibaldo C
2017-11-01
Amyloid-β peptide (Aβ) is one of the major players in the pathogenesis of Alzheimer's disease (AD). Despite numerous studies, the mechanisms by which Aβ induces neurodegeneration are not completely understood. Oxidative stress is considered a major contributor to the pathogenesis of AD, and accumulating evidence indicates that high levels of reactive oxygen species (ROS) are involved in Aβ-induced neurodegeneration. Moreover, Aβ can induce the deregulation of calcium homeostasis, which also affects mitochondrial function and triggers neuronal cell death. In the present study, we analyzed the effects of quercetin, a plant flavonoid with antioxidant properties, on oxidative stress- and Aβ-induced degeneration. Our results indicate that quercetin efficiently protected against H 2 O 2 -induced neuronal toxicity; however, this protection was only partial in rat hippocampal neurons that were treated with Aβ. Treatment with quercetin decreased ROS levels, recovered the normal morphology of mitochondria, and prevented mitochondrial dysfunction in neurons that were treated with H 2 O 2 . By contrast, quercetin treatment partially rescued hippocampal neurons from Aβ-induced mitochondrial injury. Most importantly, quercetin treatment prevented the toxic effects that are induced by H 2 O 2 in hippocampal neurons and, to a lesser extent, the Aβ-induced toxicity that is associated with the superoxide anion, which is a precursor of ROS production in mitochondria. Collectively, these results indicate that quercetin exerts differential effects on the prevention of H 2 O 2 - and Aβ-induced neurotoxicity in hippocampal neurons and may be a powerful tool for dissecting the molecular mechanisms underlying Aβ neurotoxicity.
Qian, Jing; Han, Zhuo; Wang, Haiwan; Li, Xiaoyan; Wang, Qiuyue
2014-01-01
The topic of how to prevent and reduce burnout has drawn great attention from researchers and practitioners in recent years. However, we know little about how mentoring as a form of social support exerts influence on employee burnout. This study aims to examine the contingency side of the mentoring-burnout relationship by addressing the exploratory question of whether individual differences in power distance and relationship quality play important roles in mentoring effectiveness in terms of reducing a protégé's burnout level. A total of 210 employees from a technology communications company completed the survey questionnaire. (1) A protégés' power distance moderates the negative relationship between mentoring and burnout in such a way that the relationship is stronger for protégés who are lower rather than higher in power distance; (2) mentor-protégé relationship quality moderates the negative relationship between mentoring and burnout in such a way that the relationship is stronger when the relationship quality is higher rather than lower. In sum, our results highlight the importance of studying the contingency side of mentoring effects on protégé burnout. Our findings suggest that the individuals' different cultural values of power distance and mentor-protégé relationship quality are the boundary conditions for the mentoring-burnout relationship. We therefore suggest that research on mentoring-burnout will be advanced by considering the role of the moderating process.
Matrix stiffness reverses the effect of actomyosin tension on cell proliferation.
Mih, Justin D; Marinkovic, Aleksandar; Liu, Fei; Sharif, Asma S; Tschumperlin, Daniel J
2012-12-15
The stiffness of the extracellular matrix exerts powerful effects on cell proliferation and differentiation, but the mechanisms transducing matrix stiffness into cellular fate decisions remain poorly understood. Two widely reported responses to matrix stiffening are increases in actomyosin contractility and cell proliferation. To delineate their relationship, we modulated cytoskeletal tension in cells grown across a physiological range of matrix stiffnesses. On both synthetic and naturally derived soft matrices, and across a panel of cell types, we observed a striking reversal of the effect of inhibiting actomyosin contractility, switching from the attenuation of proliferation on rigid substrates to the robust promotion of proliferation on soft matrices. Inhibiting contractility on soft matrices decoupled proliferation from cytoskeletal tension and focal adhesion organization, but not from cell spread area. Our results demonstrate that matrix stiffness and actomyosin contractility converge on cell spreading in an unexpected fashion to control a key aspect of cell fate.
Matrix stiffness reverses the effect of actomyosin tension on cell proliferation
Mih, Justin D.; Marinkovic, Aleksandar; Liu, Fei; Sharif, Asma S.; Tschumperlin, Daniel J.
2012-01-01
Summary The stiffness of the extracellular matrix exerts powerful effects on cell proliferation and differentiation, but the mechanisms transducing matrix stiffness into cellular fate decisions remain poorly understood. Two widely reported responses to matrix stiffening are increases in actomyosin contractility and cell proliferation. To delineate their relationship, we modulated cytoskeletal tension in cells grown across a physiological range of matrix stiffnesses. On both synthetic and naturally derived soft matrices, and across a panel of cell types, we observed a striking reversal of the effect of inhibiting actomyosin contractility, switching from the attenuation of proliferation on rigid substrates to the robust promotion of proliferation on soft matrices. Inhibiting contractility on soft matrices decoupled proliferation from cytoskeletal tension and focal adhesion organization, but not from cell spread area. Our results demonstrate that matrix stiffness and actomyosin contractility converge on cell spreading in an unexpected fashion to control a key aspect of cell fate. PMID:23097048
Brazilian Propolis: A Natural Product That Improved the Fungicidal Activity by Blood Phagocytes
Possamai, Muryllo Mendes; Honorio-França, Adenilda Cristina; Reinaque, Ana Paula Barcelos; França, Eduardo Luzia; Souto, Paula Cristina de Souza
2013-01-01
Natural product incorporation into microcarriers increases the bioavailability of these compounds, consequently improving their therapeutic properties. Natural products, particularly those from bees such as propolis, are widely used in popular medicine. Propolis is a powerful treatment for several diseases. In this context, the present study evaluated the effect of propolis Scaptotrigona sp. and its fractions, alone or adsorbed to polyethylene glycol (PEG) microspheres, on the activity of human phagocytes against Candida albicans. The results show that propolis exerts a stimulatory effect on these cells to assist in combating the fungus, especially as the crude extract is compared with the fractions. However, when incorporated into microspheres, these properties were significantly potentiated. These results suggest that propolis adsorbed onto PEG microspheres has immunostimulatory effects on phagocytes in human blood. Therefore, propolis may potentially be an additional natural product that can be used for a variety of therapies. PMID:23509737
Litterman, Adam J; Dudek, Arkadiusz Z; Largaespada, David A
2013-01-01
Alkylating chemotherapy exerts both antineoplastic and immunostimulatory effects. However, in addition to depleting regulatory T cells (Treg), alkylating agents also mediate a long lasting antiproliferative effect on responder lymphocytes. Our recent findings indicate that this antiproliferative effect profoundly impairs vaccination-induced immune responses, especially in the case of vaccines that target specific tumor-associated neo-antigens that do not require Treg depletion. PMID:24251080
Control and Evaluation of a Powered Transfemoral Prosthesis for Stair Ascent.
Ledoux, Elissa D; Goldfarb, Michael
2017-07-01
This paper assesses the metabolic effort exerted by three transfemoral amputees, when using a powered knee and ankle prosthesis for stair ascent, relative to ascending stairs with passive knee and ankle prostheses. The paper describes a controller that provides step-over stair ascent behavior reflective of healthy stair ascent biomechanics, and describes its implementation in a powered prosthesis prototype. Stair ascent experiments were performed with three unilateral transfemoral amputee subjects, comparing the oxygen consumption required to ascend stairs using the powered prosthesis (with a step-over gait), relative to using their daily-use energetically passive prostheses (with a step-to gait). Results indicate on average a 24% reduction in oxygen consumption and a 30% reduction in stair ascent timewhen using the powered prosthesis, relative to when using the passive prostheses. All subjects expressed a strong preference for ascending stairs using the powered prosthesis.
Protecting vulnerable research participants: a Foucault-inspired analysis of ethics committees.
Juritzen, Truls I; Grimen, Harald; Heggen, Kristin
2011-09-01
History has demonstrated the necessity of protecting research participants. Research ethics are based on a concept of asymmetry of power, viewing the researcher as powerful and potentially dangerous and establishing ethics committees as external agencies in the field of research. We argue in favour of expanding this perspective on relationships of power to encompass the ethics committees as one among several actors that exert power and that act in a relational interplay with researchers and participants. We employ Michel Foucault's ideas of power as an omnipresent force which is dynamic and unstable, as well as the notion that knowledge and power are inextricably intertwined. The article discusses how research ethics committees may affect academic freedom. In addition it is pointed out that research participants could be harmed - not only by unfortunate research practices, but also by being subjected to the protective efforts of ethics monitoring bodies.
Effect of Carbohydrate Ingestion on Ratings of Perceived Exertion during a Marathon.
ERIC Educational Resources Information Center
Utter, Alan C.; Kang, Jie; Robertson, Robert J.; Nieman, David C.; Chaloupka, Edward C.; Suminski, Richard R.; Piccinni, Cristiana R.
2002-01-01
Investigated the effects of carbohydrate substrate availability on ratings of perceived exertion (RPE) and hormonal regulation during a competitive marathon. Data on marathon runners randomly assigned to receive carbohydrate or placebo indicated that those who ingested carbohydrate rather than placebo beverages were able to run at a higher…
CHEMO-IMMUNOLOGICAL STUDIES ON LOCALIZED INFECTIONS
Lamar, Richard V.
1912-01-01
Virulent pneumococci injected into the cranial or spinal cavities of monkeys produce constantly a meningitis closely resembling pneumococcus meningitis in man, except that the experimental disease pursues a more rapid course to the invariable death of the untreated animal. An homologous immune pneumococcus serum injected into the spinal canal exerts a restraining influence upon the disease to the extent that when employed early it prevented, exceptionally, the occurrence of infection and thus saved the life of the animal, and when given later it at first retarded the disease but subsequently exerted no beneficial action and was powerless to save life. A mixture of sodium oleate, immune serum, and boric acid exerted regularly a more powerful action than immune serum alone, and not only prevented the occurrence of infection but also, when administered repeatedly, arrested the progress of an actually established infection and led, often, to the enduring and perfect recovery of the inoculated animal. It is proposed to employ a similar mixture in the direct treatment of pneumococcic meningitis and possibly of still other accessible local pneumococcic infections in man. PMID:19867598
Immunomodulatory effects of endogenous and synthetic peptides activating opioid receptors.
Pomorska, Dorota K; Gach, Katarzyna; Janecka, Anna
2014-01-01
The main role of endogenous opioid peptides is the modulation of pain. Opioid peptides exert their analgesic activity by binding to the opioid receptors distributed widely in the central nervous system (CNS). However, opioid receptors are also found on tissues and organs outside the CNS, including the cells of the immune system, indicating that opioids are capable of exerting additional effects in periphery. Morphine, which is a gold standard in the treatment of chronic pain, is well-known for its immunosuppressive effects. Much less is known about the immunomodulatory effects exerted by endogenous (enkephalins, endorphins, dynorphins and endomorphins) and synthetic peptides activating opioid receptors. In this review we tried to summarize opioid peptide-mediated modulation of immune cell functions which can be stimulatory as well as inhibitory.
Exertional heat illness: emerging concepts and advances in prehospital care.
Pryor, Riana R; Roth, Ronald N; Suyama, Joe; Hostler, David
2015-06-01
Exertional heat illness is a classification of disease with clinical presentations that are not always diagnosed easily. Exertional heat stroke is a significant cause of death in competitive sports, and the increasing popularity of marathons races and ultra-endurance competitions will make treating many heat illnesses more common for Emergency Medical Services (EMS) providers. Although evidence is available primarily from case series and healthy volunteer studies, the consensus for treating exertional heat illness, coupled with altered mental status, is whole body rapid cooling. Cold or ice water immersion remains the most effective treatment to achieve this goal. External thermometry is unreliable in the context of heat stress and direct internal temperature measurement by rectal or esophageal probes must be used when diagnosing heat illness and during cooling. With rapid recognition and implementation of effective cooling, most patients suffering from exertional heat stroke will recover quickly and can be discharged home with instructions to rest and to avoid heat stress and exercise for a minimum of 48 hours; although, further research pertaining to return to activity is warranted.
Effect of Environmental Cues on Behavioral Efficacy of Haloperidol, Olanzapine and Clozapine in Rats
Sun, Tao; Liu, Xinfeng; Li, Ming
2014-01-01
Previous studies have reported that context can powerfully modulate the inhibitory effect of an antipsychotic drug on phencyclidine (PCP)-induced hyperlocomotion (a behavioral test used to evaluate putative antipsychotic drugs). The present study investigated the experimental conditions under which environmental stimuli exert their influence through associative conditioning processes. Experiment 1 examined the extent to which prior antipsychotic treatment in the home cages affected a drug’s ability to inhibit PCP-induced hyperlocomotion in a novel motor activity test apparatus. Five days of repeated haloperidol (0.05 mg/kg, sc) and olanzapine (2.0 mg/kg, sc) treatment in the home cages still potentiated their inhibition of PCP-induced hyperlocomotion (i.e. sensitization) assessed in a new environment, whereas the clozapine (10.0 mg/kg, sc) treatment enhanced the development of clozapine tolerance, indicating a lack of environmental modulation of antipsychotic efficacy. Experiment 2 assessed the impact of different numbers of antipsychotic administrations in either the home environment or test environment (e.g. 4, 2 or 0) on a drug’s ability to inhibit PCP-induced hyperlocomotion. Repeated administration of clozapine (5.0 mg/kg, sc) or olanzapine (1.0 mg/kg, sc) for 4 consecutive days, regardless of where these treatments occurred, caused a similar level of inhibition on PCP-induced hyperlocomotion. However, 4-day haloperidol (0.03 mg/kg, sc) treatment in the test apparatus caused a significant higher inhibition than 4-day home cage treatment. Thus, more exposures to the test environment under the influence of haloperidol (but not clozapine or olanzapine) cause a stronger inhibition than fewer exposures, indicating a strong environmental modulation. Collectively, these findings suggest that prior antipsychotic treatment in one environment could alter later antipsychotic-like response assessed in a different environment under certain test conditions. Therefore, whether the circumstances surrounding antipsychotic drug administration exert a powerful control of the expression of antipsychotic-like efficacy is dependent on specific experimental and drug treatment factors. PMID:24949569
An Exploration of Iranian EFL Teachers' Perceptions on the Globalization and Hegemony of English
ERIC Educational Resources Information Center
Safari, Parvin; Razmjoo, Seyyed Ayatollah
2016-01-01
Globalization as an increasingly influencing force has led English language to become the lingua franca of the world. However, the global spread of English is considered as linguistic and cultural imperialism of English speaking countries to exert their dominance, power, culture, ideology and language over the periphery countries. The devastating…
The Power of Touch: Nonverbal Communication within Married Dyads
ERIC Educational Resources Information Center
Smith, Joann C. Seeman; Vogel, David L.; Madon, Stephanie; Edwards, Sarah R.
2011-01-01
Researchers have suggested that one function of touch in mixed-sex interactions is to exert influence over another person. Yet theories offer different explanations as to when women and men will use touch as an influence strategy. The gender politics hypothesis proposes that men touch more as a way to maintain inequalities present in society. In…
Whose Hand Rocks the Cradle? Parallel Discourses in the Baby Room
ERIC Educational Resources Information Center
Powell, Sacha; Goouch, Kathy
2012-01-01
This article explores the practice narratives of a group of 25 caregivers who work with babies in daycare settings in England and seeks to illustrate awareness of, resistance to and compliance with powerful discourses. It is argued that multiple voices exert an influence over baby room practice, disempowering the caregivers and reducing their…
Signal and Symbol: How State and Local Policies Address Data-Informed Practice
ERIC Educational Resources Information Center
Jimerson, Jo Beth; Childs, Joshua
2017-01-01
Numerous actors influence how educational policies play out in practice, but this does not mean that policies themselves are without power. Policies are crafted and enacted in part because they serve as signal and symbol: How a policy is formally codified establishes expectations, exerts norming influence, and catalyzes shifts in how issues are…
Raising the bar. Purchasers and providers must work together to meet the quality-of-care challenge.
Sandrick, K
2001-10-01
Employer coalitions, such as the Leapfrog Group and the National Business Coalition on Health, are exerting their mighty purchasing power to influence quality and patient safety in hospitals. They urge trustees to lead the way in making quality data available to the public and in holding management accountable.
ERIC Educational Resources Information Center
Putman, S. Michael
2013-01-01
Research has shown efficacy exerts a powerful influence on behavior. Classroom management represents one vehicle for demonstrations of these behaviors, yet few instruments focus solely on the measurement of this domain-specific form of efficacy. This research explored the relationship between teacher self-efficacy and classroom management through…
Power, leadership and transformation: the doctor's potential for influence.
Gabel, Stewart
2012-12-01
Power and leadership are concepts that are linked. Both are studied too infrequently in medical and health care settings, given the responsibilities and opportunities doctors and other health care personnel have to exert leadership and power appropriately to foster patient-centred and health care organisational goals. This paper reviews Raven's concept of power, clarifies the bases of power that are available to doctors in different roles and provides illustrations of the application of the bases of power in medical practice. The relationship between power and leadership is explored, with an emphasis on how power and leadership are linked through the personal characteristics and competencies of the leader. Transformational leadership illustrates the incorporation and elaboration of power strategies into a principles-driven, relationship-oriented and empirically grounded form of leadership. Illustrations of the appropriate and inappropriate use of power and leadership in health care settings are provided. The study of power, the study of leadership and their linkage should be incorporated to a greater degree into medical education at all levels. Strategies to achieve this end are suggested. © Blackwell Publishing Ltd 2012.
Reychler, Gregory; Mottart, Florian; Boland, Maelle; Wasterlain, Emmanuelle; Pieters, Thierry; Caty, Gilles; Liistro, Giuseppe
2015-05-01
Pulmonary rehabilitation is a key element in the treatment of COPD. Music has been shown to have a positive effect on parameters related to a decrease in exercise tolerance. The aim of this study was to evaluate the effect of listening to ambient music on perceived exertion during a pulmonary rehabilitation session for COPD subjects. COPD subjects randomly performed a session of pulmonary rehabilitation with or without ambient music. Perceived exertion (Borg scales), anxiety (Hospital Anxiety and Depression Scale-Anxiety Subscale), dyspnea (visual analog scale), and cardiorespiratory parameters were compared at the end of both sessions. Forty-one subjects were analyzed. The characteristics of the COPD subjects were as follows: age, 70.5 ± 8.4 y; body mass index, 22.7 ± 3.9 kg/m(2); and FEV1, 38.6 ± 12.5 % predicted. Perceived exertion was not modified by ambient music, but anxiety was improved (P = .02). Dyspnea, fatigue and cardiorespiratory parameters were not influenced by music during a typical session of the pulmonary rehabilitation program. This study demonstrates that perceived exertion during one pulmonary rehabilitation session was not influenced by ambient music. However, a positive effect on anxiety was observed. (ClinicalTrials.gov registration NCT01833260.). Copyright © 2015 by Daedalus Enterprises.
The effect of bracing availability on one-hand isometric force exertion capability.
Jones, Monica L H; Reed, Matthew P; Chaffin, Don B
2013-01-01
Environmental obstructions that workers encounter can kinematically limit the postures that they can achieve. However, such obstructions can also provide an opportunity for additional support by bracing with the hand, thigh or other body part. The reaction forces on bracing surfaces, which are in addition to those acting at the feet and task hand, are hypothesised to improve force exertion capability, and become required inputs to biomechanical analysis of tasks with bracing. The effects of kinematic constraints and associated bracing opportunities on isometric hand force were quantified in a laboratory study of 22 men and women. Analyses of one-hand maximal push, pull and lift tasks demonstrated that bracing surfaces available at the thighs and non-task hand enabled participants to exert an average of 43% more force at the task hand. Task hand force direction deviated significantly from the nominal direction for exertions performed with bracing at both medium and low task hand locations. This study quantifies the effect of bracing on kinematically constrained force exertions. Knowledge that appropriate bracing surfaces can substantially increase hand force is critical to the evaluation of task-oriented strength capability. Force estimates may also involve large off-axis components, which have clear implications for ergonomic analyses of manual tasks.
Applicability of Different Hydraulic Parameters to Describe Soil Detachment in Eroding Rills
Wirtz, Stefan; Seeger, Manuel; Zell, Andreas; Wagner, Christian; Wagner, Jean-Frank; Ries, Johannes B.
2013-01-01
This study presents the comparison of experimental results with assumptions used in numerical models. The aim of the field experiments is to test the linear relationship between different hydraulic parameters and soil detachment. For example correlations between shear stress, unit length shear force, stream power, unit stream power and effective stream power and the detachment rate does not reveal a single parameter which consistently displays the best correlation. More importantly, the best fit does not only vary from one experiment to another, but even between distinct measurement points. Different processes in rill erosion are responsible for the changing correlations. However, not all these procedures are considered in soil erosion models. Hence, hydraulic parameters alone are not sufficient to predict detachment rates. They predict the fluvial incising in the rill's bottom, but the main sediment sources are not considered sufficiently in its equations. The results of this study show that there is still a lack of understanding of the physical processes underlying soil erosion. Exerted forces, soil stability and its expression, the abstraction of the detachment and transport processes in shallow flowing water remain still subject of unclear description and dependence. PMID:23717669
Ontogenetic scaling of burrowing forces in the earthworm Lumbricus terrestris.
Quillin, K J
2000-09-01
In hydrostatic skeletons, it is the internal fluid under pressure surrounded by a body wall in tension (rather than a rigid lever) that enables the stiffening of the organism, the antagonism of muscles and the transmission of force from the muscles to the environment. This study examined the ontogenetic effects of body size on force production by an organism supported with a hydrostatic skeleton. The earthworm Lumbricus terrestris burrows by forcefully enlarging crevices in the soil. I built a force-measuring apparatus that measured the radial forces as earthworms of different sizes crawled through and enlarged pre-formed soil burrows. I also built an apparatus that measured the radial and axial forces as earthworms of different sizes attempted to elongate a dead-end burrow. Earthworms ranging in body mass m(b) from hatchlings (0.012 g) to adults (8.9 g) exerted maximum forces (F, in N) during active radial expansion of their burrows (F=0.32 m(b)(0.43)) and comparable forces during axial elongation of the burrow (F=0.26 m(b)(0.47)). Both these forces were almost an order of magnitude greater than the radial anchoring forces during normal peristalsis within burrows (F=0.04 m(b)(0.45)). All radial and axial forces scaled as body mass raised to the 2/5 power rather than to the 2/3 power expected by geometric similarity, indicating that large worms exert greater forces than small worms on an absolute scale, but the difference was less than predicted by scaling considerations. When forces were normalized by body weight, hatchlings could push 500 times their own body weight, while large adults could push only 10 times their own body weight.
Zhao, Lei; Gong, Neng; Liu, Meng; Pan, Xiaoli; Sang, Shaoming; Sun, Xiaojing; Yu, Zhe; Fang, Qi; Zhao, Na; Fei, Guoqiang; Jin, Lirong; Zhong, Chunjiu; Xu, Tianle
2014-12-01
Alzheimer's disease (AD) is a complicated, neurodegenerative disorder involving multifactorial pathogeneses and still lacks effective clinical treatment. Recent studies show that lithium exerts disease-modifying effects against AD. However, the intolerant side effects at conventional effective dosage limit the clinical use of lithium in treating AD. To explore a novel AD treatment strategy with microdose lithium, we designed and synthesized a new chemical, tri-lithium pyrroloquinoline quinone (Li3PQQ), to study the synergistic effects of low-dose lithium and pyrroloquinoline quinone, a native compound with powerful antioxidation and mitochondrial amelioration. The results showed that Li3PQQ at a relative low dose (6 and 12 mg/kg) exhibited more powerful effects in restoring the impairment of learning and memory, facilitating hippocampal long-term potentiation, and reducing cerebral amyloid deposition and phosphorylated tau level in APP/PS1 transgenic mice than that of lithium chloride at both low and high dose (5 and 100 mg/kg). We further found that Li3PQQ inhibited the activity of glycogen synthase kinase-3 and increased the activity of β-amyloid-binding alcohol dehydrogenase, which might underlie the beneficial effects of Li3PQQ on APP/PS1 transgenic mice. Our study demonstrated the efficacy of a novel AD therapeutic strategy targeting at multiple disease-causing mechanisms through the synergistic effects of microdose lithium and pyrroloquinoline quinone. Copyright © 2014 Elsevier Inc. All rights reserved.
Amino acids as central synaptic transmitters or modulators in mammalian thermoregulation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bligh, J.
1981-11-01
Of the amino acids that affect the activity of central neurons, aspartate and glutamate (which exert generally excitatory influences) and glycine, taurine, and ..gamma..-aminobutyric acid (GABA) (which generally exert inhibitory influences) are the strongest neurotransmitter candidates. As with other putative transmitter substances, their effects on body temperature when injected into the cerebral ventricles or the preoptic hypothalamus tend to vary within and between species. These effects are uninterpretable without accompanying information regarding effector activity changes and the influences of dose and ambient temperature. Observations necessary for analysis of apparent action have been made in studies of the effects of intracerebroventricularmore » injections of these amino acids into sheep. Aspartate and glutamate have similar excitatory effects on the pathway from cold sensors, whereas taurine and GABA exert inhibitory influences on the neural pathways that activate both heat production and heat loss effectors. Glycine appears to be without effect.« less
Self-Rated Accuracy of Rating of Perceived Exertion-Based Load Prescription in Powerlifters.
Helms, Eric R; Brown, Scott R; Cross, Matt R; Storey, Adam; Cronin, John; Zourdos, Michael C
2017-10-01
This study assessed male (n = 9) and female (n = 3) powerlifters' (18-49 years) ability to select loads using the repetitions in reserve-based rating of perceived exertion (RPE) scale for a single set for squat, bench press, and deadlift. Subjects trained 3× per week. For 3 weeks on nonconsecutive days in the weekly order of hypertrophy (8 repetitions at 8 RPE), power (2 repetitions at 8 RPE), and strength (3 repetitions at 9 RPE), using subject-selected loads intended to match the target RPE. Bench press and squat were performed every session and deadlift during strength and power only. Mean absolute RPE differences (|reported RPE-target RPE|) ranged from 0.22-0.44, with a mean of 0.33 ± 0.28 RPE. There were no significant RPE differences within lifts between sessions for squat or deadlift. However, bench press was closer to the target RPE for strength (0.15 ± 0.42 RPE) vs. power (-0.21 ± 0.35 RPE, p = 0.05). There were no significant differences within session between lifts for power and strength. However, bench press was closer (0.14 ± 0.44 RPE) to the target RPE than squat (-0.19 ± 0.21 RPE) during hypertrophy (p = 0.02). Squat power was closer to the target RPE in week 3 (0.08 ± 0.29 RPE) vs. 1 (-0.46 ± 0.69 RPE, p = 0.03). It seems that powerlifters can accurately select loads to reach a prescribed RPE. However, accuracy for 8-repetition sets at 8 RPE may be better for bench press compared with squat. Rating squat power-type training may take 3 weeks to reach peak accuracy. Finally, bench press RPE accuracy seems better closer rather than further from failure (i.e., 3-repetition 9 RPE sets vs. 2-repetition 8 RPE sets).
Effect of fluid ingestion on neuromuscular function during prolonged cycling exercise.
Vallier, J-M; Grego, F; Basset, F; Lepers, R; Bernard, T; Brisswalter, J
2005-04-01
To investigate the effects of fluid ingestion on neuromuscular function during prolonged cycling exercise. Eight well trained subjects exercised for 180 minutes in a moderate environment at a workload requiring approximately 60% maximal oxygen uptake. Two conditions, fluid (F) and no fluid (NF) ingestion, were investigated. During maximal voluntary isometric contraction (MVC), prolonged cycling exercise reduced (p<0.05) the maximal force generating capacity of quadriceps muscles (after three hours of cycling) and root mean square (RMS) values (after two hours of cycling) with no difference between the two conditions despite greater body weight loss (p<0.05) in NF. The mean power frequency (MPF) for vastus lateralis muscle was reduced (p<0.05) and the rate of force development (RFD) was increased (p<0.05) only during NF. During cycling exercise, integrated electromyographic activity and perceived exertion were increased in both conditions (p<0.05) with no significant effect of fluid ingestion. The results suggest that fluid ingestion did not prevent the previously reported decrease in maximal force with exercise duration, but seems to have a positive effect on some indicators of neuromuscular fatigue such as mean power frequency and rate of force development during maximal voluntary contraction. Further investigations are needed to assess the effect of change in hydration on neural mechanisms linked to the development of muscular fatigue during prolonged exercise.
Daine, Kate; Hawton, Keith; Singaravelu, Vinod; Stewart, Anne; Simkin, Sue; Montgomery, Paul
2013-01-01
Background There is concern that the internet is playing an increasing role in self-harm and suicide. In this study we systematically review and analyse research literature to determine whether there is evidence that the internet influences the risk of self-harm or suicide in young people. Methods An electronic literature search was conducted using the PsycINFO, MEDLINE, EMBASE, Scopus, and CINAHL databases. Articles of interest were those that included empirical data on the internet, self-harm or suicide, and young people. The articles were initially screened based on titles and abstracts, then by review of the full publications, after which those included in the review were subjected to data extraction, thematic analysis and quality rating. Results Youth who self-harm or are suicidal often make use of the internet. It is most commonly used for constructive reasons such as seeking support and coping strategies, but may exert a negative influence, normalising self-harm and potentially discouraging disclosure or professional help-seeking. The internet has created channels of communication that can be misused to ‘cyber-bully’ peers; both cyber-bullying and general internet use have been found to correlate with increased risk of self-harm, suicidal ideation, and depression. Correlations have also been found between internet exposure and violent methods of self-harm. Conclusions Internet use may exert both positive and negative effects on young people at risk of self-harm or suicide. Careful high quality research is needed to better understand how internet media may exert negative influences and should also focus on how the internet might be utilised to intervene with vulnerable young people. PMID:24204868
Hahm, Hyeouk Chris; Lee, Jieha; Rough, Kathryn; Strathdee, Steffanie A
2012-01-01
We examined the prevalence of three domains of sexual behaviors among young Asian-American women: sexual experiences, safer sex practices, and potential HIV risk behaviors. We also investigated the impact of gender power control on these domains. Among sexually experienced women, 51% reported using condoms during their most recent sex act, 63% reported inconsistent condom use, and 18% reported ever having forced sex. Multiple logistic regression analyses revealed that women's perceived lower relationship power control was not associated with vaginal sex or safer sex practices, but it was powerfully associated with forced sex and all three potential HIV risk behaviors. This study demonstrates that control within young Asian-American women's intimate relationships exerts different associations depending on the type of sexual behavior. The application of the Theory of Gender and Power should be employed with prudence when designing HIV interventions for this population.
Lee, Jieha; Rough, Kathryn; Strathdee, Steffanie A.
2012-01-01
We examined the prevalence of three domains of sexual behaviors among young Asian-American women: sexual experiences, safer sex practices, and potential HIV risk behaviors. We also investigated the impact of gender power control on these domains. Among sexually experienced women, 51% reported using condoms during their most recent sex act, 63% reported inconsistent condom use, and 18% reported ever having forced sex. Multiple logistic regression analyses revealed that women’s perceived lower relationship power control was not associated with vaginal sex or safer sex practices, but it was powerfully associated with forced sex and all three potential HIV risk behaviors. This study demonstrates that control within young Asian-American women’s intimate relationships exerts different associations depending on the type of sexual behavior. The application of the Theory of Gender and Power should be employed with prudence when designing HIV interventions for this population. PMID:21259042
Genetic risk and a primary role for cell-mediated immune mechanisms in multiple sclerosis.
Sawcer, Stephen; Hellenthal, Garrett; Pirinen, Matti; Spencer, Chris C A; Patsopoulos, Nikolaos A; Moutsianas, Loukas; Dilthey, Alexander; Su, Zhan; Freeman, Colin; Hunt, Sarah E; Edkins, Sarah; Gray, Emma; Booth, David R; Potter, Simon C; Goris, An; Band, Gavin; Oturai, Annette Bang; Strange, Amy; Saarela, Janna; Bellenguez, Céline; Fontaine, Bertrand; Gillman, Matthew; Hemmer, Bernhard; Gwilliam, Rhian; Zipp, Frauke; Jayakumar, Alagurevathi; Martin, Roland; Leslie, Stephen; Hawkins, Stanley; Giannoulatou, Eleni; D'alfonso, Sandra; Blackburn, Hannah; Martinelli Boneschi, Filippo; Liddle, Jennifer; Harbo, Hanne F; Perez, Marc L; Spurkland, Anne; Waller, Matthew J; Mycko, Marcin P; Ricketts, Michelle; Comabella, Manuel; Hammond, Naomi; Kockum, Ingrid; McCann, Owen T; Ban, Maria; Whittaker, Pamela; Kemppinen, Anu; Weston, Paul; Hawkins, Clive; Widaa, Sara; Zajicek, John; Dronov, Serge; Robertson, Neil; Bumpstead, Suzannah J; Barcellos, Lisa F; Ravindrarajah, Rathi; Abraham, Roby; Alfredsson, Lars; Ardlie, Kristin; Aubin, Cristin; Baker, Amie; Baker, Katharine; Baranzini, Sergio E; Bergamaschi, Laura; Bergamaschi, Roberto; Bernstein, Allan; Berthele, Achim; Boggild, Mike; Bradfield, Jonathan P; Brassat, David; Broadley, Simon A; Buck, Dorothea; Butzkueven, Helmut; Capra, Ruggero; Carroll, William M; Cavalla, Paola; Celius, Elisabeth G; Cepok, Sabine; Chiavacci, Rosetta; Clerget-Darpoux, Françoise; Clysters, Katleen; Comi, Giancarlo; Cossburn, Mark; Cournu-Rebeix, Isabelle; Cox, Mathew B; Cozen, Wendy; Cree, Bruce A C; Cross, Anne H; Cusi, Daniele; Daly, Mark J; Davis, Emma; de Bakker, Paul I W; Debouverie, Marc; D'hooghe, Marie Beatrice; Dixon, Katherine; Dobosi, Rita; Dubois, Bénédicte; Ellinghaus, David; Elovaara, Irina; Esposito, Federica; Fontenille, Claire; Foote, Simon; Franke, Andre; Galimberti, Daniela; Ghezzi, Angelo; Glessner, Joseph; Gomez, Refujia; Gout, Olivier; Graham, Colin; Grant, Struan F A; Guerini, Franca Rosa; Hakonarson, Hakon; Hall, Per; Hamsten, Anders; Hartung, Hans-Peter; Heard, Rob N; Heath, Simon; Hobart, Jeremy; Hoshi, Muna; Infante-Duarte, Carmen; Ingram, Gillian; Ingram, Wendy; Islam, Talat; Jagodic, Maja; Kabesch, Michael; Kermode, Allan G; Kilpatrick, Trevor J; Kim, Cecilia; Klopp, Norman; Koivisto, Keijo; Larsson, Malin; Lathrop, Mark; Lechner-Scott, Jeannette S; Leone, Maurizio A; Leppä, Virpi; Liljedahl, Ulrika; Bomfim, Izaura Lima; Lincoln, Robin R; Link, Jenny; Liu, Jianjun; Lorentzen, Aslaug R; Lupoli, Sara; Macciardi, Fabio; Mack, Thomas; Marriott, Mark; Martinelli, Vittorio; Mason, Deborah; McCauley, Jacob L; Mentch, Frank; Mero, Inger-Lise; Mihalova, Tania; Montalban, Xavier; Mottershead, John; Myhr, Kjell-Morten; Naldi, Paola; Ollier, William; Page, Alison; Palotie, Aarno; Pelletier, Jean; Piccio, Laura; Pickersgill, Trevor; Piehl, Fredrik; Pobywajlo, Susan; Quach, Hong L; Ramsay, Patricia P; Reunanen, Mauri; Reynolds, Richard; Rioux, John D; Rodegher, Mariaemma; Roesner, Sabine; Rubio, Justin P; Rückert, Ina-Maria; Salvetti, Marco; Salvi, Erika; Santaniello, Adam; Schaefer, Catherine A; Schreiber, Stefan; Schulze, Christian; Scott, Rodney J; Sellebjerg, Finn; Selmaj, Krzysztof W; Sexton, David; Shen, Ling; Simms-Acuna, Brigid; Skidmore, Sheila; Sleiman, Patrick M A; Smestad, Cathrine; Sørensen, Per Soelberg; Søndergaard, Helle Bach; Stankovich, Jim; Strange, Richard C; Sulonen, Anna-Maija; Sundqvist, Emilie; Syvänen, Ann-Christine; Taddeo, Francesca; Taylor, Bruce; Blackwell, Jenefer M; Tienari, Pentti; Bramon, Elvira; Tourbah, Ayman; Brown, Matthew A; Tronczynska, Ewa; Casas, Juan P; Tubridy, Niall; Corvin, Aiden; Vickery, Jane; Jankowski, Janusz; Villoslada, Pablo; Markus, Hugh S; Wang, Kai; Mathew, Christopher G; Wason, James; Palmer, Colin N A; Wichmann, H-Erich; Plomin, Robert; Willoughby, Ernest; Rautanen, Anna; Winkelmann, Juliane; Wittig, Michael; Trembath, Richard C; Yaouanq, Jacqueline; Viswanathan, Ananth C; Zhang, Haitao; Wood, Nicholas W; Zuvich, Rebecca; Deloukas, Panos; Langford, Cordelia; Duncanson, Audrey; Oksenberg, Jorge R; Pericak-Vance, Margaret A; Haines, Jonathan L; Olsson, Tomas; Hillert, Jan; Ivinson, Adrian J; De Jager, Philip L; Peltonen, Leena; Stewart, Graeme J; Hafler, David A; Hauser, Stephen L; McVean, Gil; Donnelly, Peter; Compston, Alastair
2011-08-10
Multiple sclerosis is a common disease of the central nervous system in which the interplay between inflammatory and neurodegenerative processes typically results in intermittent neurological disturbance followed by progressive accumulation of disability. Epidemiological studies have shown that genetic factors are primarily responsible for the substantially increased frequency of the disease seen in the relatives of affected individuals, and systematic attempts to identify linkage in multiplex families have confirmed that variation within the major histocompatibility complex (MHC) exerts the greatest individual effect on risk. Modestly powered genome-wide association studies (GWAS) have enabled more than 20 additional risk loci to be identified and have shown that multiple variants exerting modest individual effects have a key role in disease susceptibility. Most of the genetic architecture underlying susceptibility to the disease remains to be defined and is anticipated to require the analysis of sample sizes that are beyond the numbers currently available to individual research groups. In a collaborative GWAS involving 9,772 cases of European descent collected by 23 research groups working in 15 different countries, we have replicated almost all of the previously suggested associations and identified at least a further 29 novel susceptibility loci. Within the MHC we have refined the identity of the HLA-DRB1 risk alleles and confirmed that variation in the HLA-A gene underlies the independent protective effect attributable to the class I region. Immunologically relevant genes are significantly overrepresented among those mapping close to the identified loci and particularly implicate T-helper-cell differentiation in the pathogenesis of multiple sclerosis.
Mündel, Toby; King, Jenny; Collacott, Esther; Jones, David A
2006-09-01
The effect of different drink temperatures on the perception of exertion and exercise endurance has not been extensively investigated. Consequently, the purpose of the present study was to examine the effect of drink temperature on fluid intake and endurance during cycling in the heat. Eight healthy, non-acclimated males (26 +/- 7 years; maximum oxygen uptake, 54 +/- 5 ml kg(-1) min(-1); mean +/- S.D.) cycled to exhaustion at 34 degrees C and at 65% of their peak aerobic power, consuming a drink at either 19 degrees C (CON) or 4 degrees C (COLD). Six of the eight subjects cycled for longer during COLD, with exhaustion occurring at 62 +/- 4 min, compared to 55 +/- 4 min for CON (P < 0.05; mean +/- S.E.M.). Subjects consumed significantly more fluid during COLD compared to CON (1.3 +/- 0.3 l h(-1) compared to 1.0 +/- 0.2 l h(-1); P < 0.05). Heart rate tended to be lower by approximately 5 beats min(-1) during COLD, and rectal temperature during the second half of the exercise period was approximately 0.25 degrees C lower during the COLD trial; however, these trends were not significant (P = 0.08 and P = 0.07, respectively). No differences were observed between trials for ventilation, concentrations of prolactin, glucose and lactate or perceived exertion. It is concluded that a drink at 4 degrees C during exercise in the heat enhances fluid consumption and improves endurance by acting as a heat sink, attenuating the rise in body temperature and therefore reducing the effects of heat stress.
Arokoyo, Dennis Seyi; Oyeyipo, Ibukun Peter; Du Plessis, Stefan Simon; Aboua, Yapo Guillaume
2018-01-01
Oxidative stress is frequently identified as a key element in the pathophysiology of many complications of diabetes mellitus, including reproductive complications. The antioxidant potential of medicinal plants have been suggested for therapeutic focus of diseases in recent reports. To investigate the effect of Basella alba (Ba) aqueous leave extract on diabetes-induced oxidative stress. Forty male Wistar rats (8-10 weeks) were randomly divided into four groups ( n = 10) and treated as follows; Control (C + Ns) and Diabetic (D + Ns) animals received oral normal saline 0.5 ml/100 g body weight daily, while Healthy Treatment (H + Ba) and Diabetic Treatment (D + Ba) rats were given Ba extract at an oral dose of 200 mg/kg body weight daily. Treatment was by gavage and lasted 4 weeks in all groups. Diabetes was induced in D + Ns and D + Ba rats by single intraperitoneal injection of streptozotocin (55 mg/kg) and fasting blood sugar (FBS) recorded weekly in all rats afterwards. Animals were euthanized at the end of the experiment and blood samples, pancreas, testes, and epididymis were preserved for analysis of oxidative stress biomarkers. Oral administration of aqueous leave extract of Ba significantly ( P < 0.0001) lowered FBS in D + Ba rats. There was significantly higher blood superoxide dismutase activity and serum ferric reducing antioxidant power, but lower serum concentration of conjugated dienes and thiobarbituric acid reactive substances in D + Ba compared to D + Ns rats ( P < 0.05). Ba exerts antioxidant effects in the gonads by enhancing antioxidant parameters in circulating blood, but not necessarily in the gonadal tissues. Oral treatment of diabetic rats with aqueous leave extract of Basella alba exerts antioxidant effects in the gonads by enhancing antioxidant parameters in circulating blood, but not necessarily in the gonadal tissues. Abbreviations Used: AP - Antioxidant parameters, Ba - Basella alba , CAT - Catalase, CDs - Conjugated dienes, DM - Diabetes mellitus, FBS - Fasting blood sugar, FRAP - Ferric reducing antioxidant power, GSH - reduced glutathione, Ns - Normal saline, ORAC - oxygen radical antioxidant capacity, RNS - reactive nitrogen species, ROS - reactive oxygen species, SOD - superoxide dismutase, TAC - Total antioxidant capacity, TBARS - thiobarbituric acid reactive substances, TEAC - trolox equivalent antioxidant capacity.
Health Benefits of an Innovative Exercise Program for Mitochondrial Disorders.
Fiuza-Luces, Carmen; Díez-Bermejo, Jorge; Fernández-DE LA Torre, Miguel; Rodríguez-Romo, Gabriel; Sanz-Ayán, Paz; Delmiro, Aitor; Munguía-Izquierdo, Diego; Rodríguez-Gómez, Irene; Ara, Ignacio; Domínguez-González, Cristina; Arenas, Joaquín; Martín, Miguel A; Lucia, Alejandro; Morán, María
2018-06-01
We determined the effects of an innovative 8-wk exercise intervention (aerobic, resistance, and inspiratory muscle training) for patients with mitochondrial disease. Several end points were assessed in 12 patients (19-59 yr, 4 women) at pretraining, posttraining, and after 4-wk detraining: aerobic power, muscle strength/power and maximal inspiratory pressure (main end points), ability to perform activities of daily living, body composition, quality of life, and blood myokines (secondary end points). The program was safe, with patients' adherence being 94% ± 5%. A significant time effect was found for virtually all main end points (P ≤ 0.004), indicating a training improvement. Similar findings (P ≤ 0.003) were found for activities of daily living tests, total/trunk/leg lean mass, total fat mass, femoral fracture risk, and general health perception. No differences were found for blood myokines, except for an acute exertional increase in interleukin 8 at posttraining/detraining (P = 0.002) and in fatty acid binding protein 3 at detraining (P = 0.002). An intervention including novel exercises for mitochondrial disease patients (e.g., inspiratory muscle training) produced benefits in numerous indicators of physical capacity and induced a previously unreported shift toward a healthier body composition phenotype.
Erdem, Sinem Aslan; Senol, F Sezer; Budakoglu, Esin; Orhan, Ilkay Erdogan; Sener, Bilge
2016-01-01
The hydroalcoholic extracts of the Turkish traditional coffee samples from 18 commercial brands were tested for their neurobiological effects through enzyme inhibition based on enzyme-linked immunosorbance microtiter assays against acetylcholinesterase, butyrylcholinesterase, and tyrosinase, linked to Alzheimer's and Parkinson's diseases. The extracts were also subjected to several antioxidant test systems to define their antiradical, metal-chelation capacity, and reducing power. Total phenol and flavonoid contents in the extracts were delineated by spectrophotometric methods, while chlorogenic acid in the coffee samples was quantified by high-pressure liquid chromatography. The extracts displayed low to moderate inhibition (from 2.13 ± 0.01% to 36.12 ± 1.07% at 200 μg/mL) against the tested enzymes, whereas they had notable 2,2'-diphenyl-1-picrylhydrazyl radical scavenging activity up to 56.15 ± 2.03% at 200 μg/mL. The extracts exerted a remarkable ferric-reducing antioxidant power values, while chlorogenic acid was found to range between 0.288 ± 0.005% and 2.335 ± 0.010%. Copyright © 2015. Published by Elsevier B.V.
The neural dynamics underlying the interpersonal effects of emotional expression on decision making.
Chen, Xuhai; Zheng, Tingting; Han, Lingzi; Chang, Yingchao; Luo, Yangmei
2017-04-20
Although numerous studies explore the effects of emotion on decision-making, the existing research has mainly focused on the influence of intrapersonal emotions, leaving the influence of one person's emotions on another's decisions underestimated. To specify how interpersonal emotions shape decision-making and delineate the underlying neural dynamics involved, the present study examined brain responses to utilitarian feedback combined with angry or happy faces in competitive and cooperative contexts. Behavioral results showed that participants responded slower following losses than wins when competitors express happiness but responded faster following losses than wins when cooperators express anger. Importantly, angry faces in competitive context reversed the differentiation pattern of feedback-related negativity (FRN) between losses and wins and diminished the difference between losses and wins on both P300 and theta power, but only diminished the difference on FRN between losses and wins in cooperative context. However, when partner displays happiness, losses versus wins elicited larger FRN and theta power in competitive context but smaller P300 in both contexts. These results suggest that interpersonal emotions shape decisions during both automatic motivational salience valuation (FRN) and conscious cognitive appraisal (P300) stages of processing, in which different emotional expressions exert interpersonal influence through different routes.
Morales, Jose; Buscà, Bernat; Solana-Tramunt, Mònica; Miró, Adrià
2015-12-01
The latest findings on the ergogenic effects of a dentistry-design, bite-aligning mouthpiece require additional research to assess its impact on anaerobic ability and ventilatory parameters. This paper was aimed at determining the ergogenic acute effects of wearing a custom-made mouthpiece on oral airflow dynamics, 30-s Wingate Anaerobic Test performance parameters. Twenty-eight healthy and physically-active male subjects (age: 24.50 ± 3.32, height: 181.34 ± 7.4, weight: 78.14 ± 8.21), were voluntarily studied. The subjects were first briefed on the test protocols, and then performed the 30s Wingate test and Spirometer test. The experimental trials were performed in a random counterbalanced order. We evaluate maximum expiratory volume (VEmax L min(-1)), mean power (W kg(-1)), peak power (W kg(-1)), time to peak (s), rate to fatigue (Ws(-1)) and lactate production (mMol L(-1)), rate of perceived exertion (RPE). There were significant differences between mouthguard and no-mouthguard conditions in mean power (W kg(-1)), peak power (W kg(-1)), time to peak (s), and rate to fatigue (Ws(-1)) for the 30-s Wingate Anaerobic Test. Significantly lower lactate production (mMol L(-1)) was observed, in mouthguard condition but no significant differences were found in RPE. In airflow dynamics, the VEmax L min(-1) was significantly higher when comparing the mouthguard and the no mouthguard conditions in both forced and unforced conditions. In conclusion, wearing a customized mouthguard improves anaerobic ability and increases forced expiratory volume. This study will help practitioners improve athlete's performance in anaerobic activities where high intensity action might provoke jaw-clenching, contributing in reductions of lactate and fatigue, and improving ventilatory parameters. Copyright © 2015 Elsevier B.V. All rights reserved.
The effects of cloud radiative forcing on an ocean-covered planet
NASA Technical Reports Server (NTRS)
Randall, David A.
1990-01-01
Cumulus anvil clouds, whose importance has been emphasized by observationalists in recent years, exert a very powerful influence on deep tropical convection by tending to radiatively destabilize the troposphere. In addition, they radiatively warm the column in which they reside. Their strong influence on the simulated climate argues for a much more refined parameterization in the General Circulation Model (GCM). For Seaworld, the atmospheric cloud radiative forcing (ACRF) has a powerful influence on such basic climate parameters as the strength of the Hadley circulation, the existence of a single narrow InterTropical Convergence Zone (ITCZ), and the precipitable water content of the atmosphere. It seems likely, however, that in the real world the surface CRF feeds back negatively to suppress moist convection and the associated cloudiness, and so tends to counteract the effects of the ACRF. Many current climate models have fixed sea surface temperatures but variable land-surface temperatures. The tropical circulations of such models may experience a position feedback due to ACRF over the oceans, and a negative or weak feedback due to surface CRF over the land. The overall effects of the CRF on the climate system can only be firmly established through much further analysis, which can benefit greatly from the use of a coupled ocean-atmospheric model.
Jeong, G. Y.; Kim, Yeon Soo; Jamison, L. M.; ...
2017-02-20
U-Mo/Al dispersion fuel irradiated to high burnup at high power (high fission rate) exhibited microstructural changes such as deformation of the fuel particles, pore growth, and rupture of the Al matrix. The driving force for these microstructural changes was meat swelling caused by a combination of fuel particle swelling and interaction layer growth. Five miniplates with well-recorded fabrication data and irradiation conditions were selected, and their PIE data was analyzed. ABAQUS finite element analysis (FEA) was utilized to simulate the microstructural evolution of the plates. Using the simulation results shear stress, effective stress and hydrostatic stress exerted on both themore » fuel particles and the Al matrix were determined. The effects of fabrication and irradiation variables on stress-induced microstructural evolutions, such as pore growth in the interaction layers and Al matrix rupture, were investigated. The observed microstructural changes were consistent with the calculated stress distribution in the meat.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jeong, G. Y.; Kim, Yeon Soo; Jamison, L. M.
U-Mo/Al dispersion fuel irradiated to high burnup at high power (high fission rate) exhibited microstructural changes such as deformation of the fuel particles, pore growth, and rupture of the Al matrix. The driving force for these microstructural changes was meat swelling caused by a combination of fuel particle swelling and interaction layer growth. Five miniplates with well-recorded fabrication data and irradiation conditions were selected, and their PIE data was analyzed. ABAQUS finite element analysis (FEA) was utilized to simulate the microstructural evolution of the plates. Using the simulation results shear stress, effective stress and hydrostatic stress exerted on both themore » fuel particles and the Al matrix were determined. The effects of fabrication and irradiation variables on stress-induced microstructural evolutions, such as pore growth in the interaction layers and Al matrix rupture, were investigated. The observed microstructural changes were consistent with the calculated stress distribution in the meat.« less
The effect of music on 10-km cycle time-trial performance.
Hagen, Jana; Foster, Carl; Rodríguez-Marroyo, Jose; de Koning, Jos J; Mikat, Richard P; Hendrix, Charles R; Porcari, John P
2013-01-01
Music is widely used as an ergogenic aid in sport, but there is little evidence of its effectiveness during closed-loop athletic events. In order to determine the effectiveness of music as an ergogenic aid, well-trained and task-habituated cyclists performed 10-km cycle time trials either while listening to self-selected motivational music or with auditory input blocked. There were no statistically significant differences in performance time or physiological or psychological markers related to music (time-trial duration17.75 ± 2.10 vs 17.81 ± 2.06 min, mean power output 222 ± 66 vs 220 ± 65 W, peak heart rate184 ± 9 vs 183 ± 8 beats/min, peak blood lactate12.1 ± 2.6 vs 11.9 ± 2.1 mmol/L, and final rating of perceived exertion 8.4 ± 1.5 vs 8.5 ± 1.6). It is concluded that during exercise at competitive intensity, there is no meaningful effect of music on either performance or physiology.
A novel therapeutic effect of statins on nephrogenic diabetes insipidus
Bonfrate, Leonilde; Procino, Giuseppe; Wang, David Q-H; Svelto, Maria; Portincasa, Piero
2015-01-01
Statins competitively inhibit hepatic 3-hydroxy-3-methylglutaryl-coenzyme A reductase, resulting in reduced plasma total and low-density lipoprotein cholesterol levels. Recently, it has been shown that statins exert additional ‘pleiotropic’ effects by increasing expression levels of the membrane water channels aquaporin 2 (AQP2). AQP2 is localized mainly in the kidney and plays a critical role in determining cellular water content. This additional effect is independent of cholesterol homoeostasis, and depends on depletion of mevalonate-derived intermediates of sterol synthetic pathways, i.e. farnesylpyrophosphate and geranylgeranylpyrophosphate. By up-regulating the expression levels of AQP2, statins increase water reabsorption by the kidney, thus opening up a new avenue in treating patients with nephrogenic diabetes insipidus (NDI), a hereditary disease that yet lacks high-powered and limited side effects therapy. Aspects related to water balance determined by AQP2 in the kidney, as well as standard and novel therapeutic strategies of NDI are discussed. PMID:25594563
Sayers, W Michael; Sayette, Michael A
2013-09-01
Research on emotion suppression has shown a rebound effect, in which expression of the targeted emotion increases following a suppression attempt. In prior investigations, participants have been explicitly instructed to suppress their responses, which has drawn the act of suppression into metaconsciousness. Yet emerging research emphasizes the importance of nonconscious approaches to emotion regulation. This study is the first in which a craving rebound effect was evaluated without simultaneously raising awareness about suppression. We aimed to link spontaneously occurring attempts to suppress cigarette craving to increased smoking motivation assessed immediately thereafter. Smokers (n = 66) received a robust cued smoking-craving manipulation while their facial responses were videotaped and coded using the Facial Action Coding System. Following smoking-cue exposure, participants completed a behavioral choice task previously found to index smoking motivation. Participants evincing suppression-related facial expressions during cue exposure subsequently valued smoking more than did those not displaying these expressions, which suggests that internally generated suppression can exert powerful rebound effects.
ERIC Educational Resources Information Center
Molloy, Sean
2012-01-01
Mina Shaughnessy continues to exert powerful influences over Basic Writing practices, discourses and pedagogy thirty-five years after her death: Basic Writing remains in some ways trapped by Shaughnessy's legacy in what Min-Zhan Lu labeled as essentialism, accommodationism and linguistic innocence. High-stakes writing tests, a troubling hallmark…
Alcohol advertising and adolescents.
Strasburger, Victor C
2002-04-01
Considerable research now exists that the media may exert a powerful influence on adolescents' drug-taking behavior. Teens view an average of 2,000 beer and wine ads per year in the US. In addition, television shows, movies, and music videos contain considerable amounts of alcohol use. This article will discuss the available research and offers suggestions to make the media healthier for teenagers.
How the Timing and Quality of Early Experiences Influence the Development of Brain Architecture
ERIC Educational Resources Information Center
Fox, Sharon E.; Levitt, Pat; Nelson, Charles A., III.
2010-01-01
Early life events can exert a powerful influence on both the pattern of brain architecture and behavioral development. In this study a conceptual framework is provided for considering how the structure of early experience gets "under the skin." The study begins with a description of the genetic framework that lays the foundation for brain…
Analytical Solutions for Rumor Spreading Dynamical Model in a Social Network
NASA Astrophysics Data System (ADS)
Fallahpour, R.; Chakouvari, S.; Askari, H.
2015-03-01
In this paper, Laplace Adomian decomposition method is utilized for evaluating of spreading model of rumor. Firstly, a succinct review is constructed on the subject of using analytical methods such as Adomian decomposion method, Variational iteration method and Homotopy Analysis method for epidemic models and biomathematics. In continue a spreading model of rumor with consideration of forgetting mechanism is assumed and subsequently LADM is exerted for solving of it. By means of the aforementioned method, a general solution is achieved for this problem which can be readily employed for assessing of rumor model without exerting any computer program. In addition, obtained consequences for this problem are discussed for different cases and parameters. Furthermore, it is shown the method is so straightforward and fruitful for analyzing equations which have complicated terms same as rumor model. By employing numerical methods, it is revealed LADM is so powerful and accurate for eliciting solutions of this model. Eventually, it is concluded that this method is so appropriate for this problem and it can provide researchers a very powerful vehicle for scrutinizing rumor models in diverse kinds of social networks such as Facebook, YouTube, Flickr, LinkedIn and Tuitor.
Hydroperiod regime controls the organization of plant species in wetlands
Foti, Romano; del Jesus, Manuel; Rinaldo, Andrea; Rodriguez-Iturbe, Ignacio
2012-01-01
With urban, agricultural, and industrial needs growing throughout the past decades, wetland ecosystems have experienced profound changes. Most critically, the biodiversity of wetlands is intimately linked to its hydrologic dynamics, which in turn are being drastically altered by ongoing climate changes. Hydroperiod regimes, e.g., percentage of time a site is inundated, exert critical control in the creation of niches for different plant species in wetlands. However, the spatial signatures of the organization of plant species in wetlands and how the different drivers interact to yield such signatures are unknown. Focusing on Everglades National Park (ENP) in Florida, we show here that cluster sizes of each species follow a power law probability distribution and that such clusters have well-defined fractal characteristics. Moreover, we individuate and model those signatures via the interplay between global forcings arising from the hydroperiod regime and local controls exerted by neighboring vegetation. With power law clustering often associated with systems near critical transitions, our findings are highly relevant for the management of wetland ecosystems. In addition, our results show that changes in climate and land management have a quantifiable predictable impact on the type of vegetation and its spatial organization in wetlands. PMID:23150589
Robust Optimization Design Algorithm for High-Frequency TWTs
NASA Technical Reports Server (NTRS)
Wilson, Jeffrey D.; Chevalier, Christine T.
2010-01-01
Traveling-wave tubes (TWTs), such as the Ka-band (26-GHz) model recently developed for the Lunar Reconnaissance Orbiter, are essential as communication amplifiers in spacecraft for virtually all near- and deep-space missions. This innovation is a computational design algorithm that, for the first time, optimizes the efficiency and output power of a TWT while taking into account the effects of dimensional tolerance variations. Because they are primary power consumers and power generation is very expensive in space, much effort has been exerted over the last 30 years to increase the power efficiency of TWTs. However, at frequencies higher than about 60 GHz, efficiencies of TWTs are still quite low. A major reason is that at higher frequencies, dimensional tolerance variations from conventional micromachining techniques become relatively large with respect to the circuit dimensions. When this is the case, conventional design- optimization procedures, which ignore dimensional variations, provide inaccurate designs for which the actual amplifier performance substantially under-performs that of the design. Thus, this new, robust TWT optimization design algorithm was created to take account of and ameliorate the deleterious effects of dimensional variations and to increase efficiency, power, and yield of high-frequency TWTs. This design algorithm can help extend the use of TWTs into the terahertz frequency regime of 300-3000 GHz. Currently, these frequencies are under-utilized because of the lack of efficient amplifiers, thus this regime is known as the "terahertz gap." The development of an efficient terahertz TWT amplifier could enable breakthrough applications in space science molecular spectroscopy, remote sensing, nondestructive testing, high-resolution "through-the-wall" imaging, biomedical imaging, and detection of explosives and toxic biochemical agents.
Zucca, Paolo; Rosa, Antonella; Tuberoso, Carlo I. G.; Piras, Alessandra; Rinaldi, Andrea C.; Sanjust, Enrico; Dessì, Maria A.; Rescigno, Antonio
2013-01-01
Cynomorium coccineum is an edible, non-photosynthetic plant widespread along the coasts of the Mediterranean Sea. The medicinal properties of Maltese mushroom—one of the oldest vernacular names used to identify this species—have been kept in high regard since ancient times to the present day. We evaluated the antioxidant potential of fresh specimens of C. coccineum picked in Sardinia, Italy. Both aqueous and methanolic extracts were tested by using multiple assay systems (DPPH, FRAP, TEAC, ORAC-PYR). Total phenolics and flavonoids were also determined. Gallic acid and cyanidin 3-O-glucoside were identified as the main constituents and measured. Both extracts showed antioxidant capacities; ORAC-PYR assay gave the highest antioxidant value in both cases. The methanolic extract was further investigated with in vitro biological models of lipid oxidation; it showed a significant activity in preventing cholesterol degradation and exerted protection against Cu2+-mediated degradation of the liposomal unsaturated fatty acids. Results of the present study demonstrate that the extracts of C. coccineum show a significant total antioxidant power and also exert an in vitro protective effect in different bio-assays of oxidative stress. Therefore, Maltese mushroom can be considered a valuable source of antioxidants and phytochemicals useful in the preparation of nutraceuticals and functional foods. PMID:23344249
Within-group behavioural consequences of between-group conflict: a prospective review.
Radford, Andrew N; Majolo, Bonaventura; Aureli, Filippo
2016-11-30
Conflict is rife in group-living species and exerts a powerful selective force. Group members face a variety of threats from extra-group conspecifics, from individuals looking for reproductive opportunities to rival groups seeking resources. Theory predicts that such between-group conflict should influence within-group behaviour. However, compared with the extensive literature on the consequences of within-group conflict, relatively little research has considered the behavioural impacts of between-group conflict. We give an overview of why between-group conflict is expected to influence subsequent behaviour among group members. We then use what is known about the consequences of within-group conflict to generate testable predictions about how between-group conflict might affect within-group behaviour in the aftermath. We consider the types of behaviour that could change and how the role of different group members in the conflict can exert an influence. Furthermore, we discuss how conflict characteristics and outcome, group size, social structure and within-group relationship quality might modulate post-conflict behavioural changes. Finally, we propose the need for consistent definitions, a broader range of examined behaviours and taxa, individual-focused data collection, complementary observational and experimental approaches, and a consideration of lasting effects if we are to understand fully the significant influence of between-group conflict on social behaviour. © 2016 The Author(s).
Within-group behavioural consequences of between-group conflict: a prospective review
Aureli, Filippo
2016-01-01
Conflict is rife in group-living species and exerts a powerful selective force. Group members face a variety of threats from extra-group conspecifics, from individuals looking for reproductive opportunities to rival groups seeking resources. Theory predicts that such between-group conflict should influence within-group behaviour. However, compared with the extensive literature on the consequences of within-group conflict, relatively little research has considered the behavioural impacts of between-group conflict. We give an overview of why between-group conflict is expected to influence subsequent behaviour among group members. We then use what is known about the consequences of within-group conflict to generate testable predictions about how between-group conflict might affect within-group behaviour in the aftermath. We consider the types of behaviour that could change and how the role of different group members in the conflict can exert an influence. Furthermore, we discuss how conflict characteristics and outcome, group size, social structure and within-group relationship quality might modulate post-conflict behavioural changes. Finally, we propose the need for consistent definitions, a broader range of examined behaviours and taxa, individual-focused data collection, complementary observational and experimental approaches, and a consideration of lasting effects if we are to understand fully the significant influence of between-group conflict on social behaviour. PMID:27903869
Effects of music tempo upon submaximal cycling performance.
Waterhouse, J; Hudson, P; Edwards, B
2010-08-01
In an in vivo laboratory controlled study, 12 healthy male students cycled at self-chosen work-rates while listening to a program of six popular music tracks of different tempi. The program lasted about 25 min and was performed on three occasions--unknown to the participants, its tempo was normal, increased by 10% or decreased by 10%. Work done, distance covered and cadence were measured at the end of each track, as were heart rate and subjective measures of exertion, thermal comfort and how much the music was liked. Speeding up the music program increased distance covered/unit time, power and pedal cadence by 2.1%, 3.5% and 0.7%, respectively; slowing the program produced falls of 3.8%, 9.8% and 5.9%. Average heart rate changes were +0.1% (faster program) and -2.2% (slower program). Perceived exertion and how much the music was liked increased (faster program) by 2.4% and 1.3%, respectively, and decreased (slower program) by 3.6% and 35.4%. That is, healthy individuals performing submaximal exercise not only worked harder with faster music but also chose to do so and enjoyed the music more when it was played at a faster tempo. Implications of these findings for improving training regimens are discussed.
Olafiranye, Oladipupo; Hostler, David; Winger, Daniel G; Wang, Li; Reis, Steven E
2015-06-01
Peripheral arterial stiffness and endothelial function, which are independent predictors of cardiac events, are abnormal in firefighters. We examined the effects of aspirin on peripheral arterial stiffness and endothelial function in firefighters. Fifty-two firefighters were randomized to receive daily 81 mg aspirin or placebo for 14 days before treadmill exercise in thermal protection clothing, and a single dose of 325 mg aspirin or placebo immediately following exertion. Peripheral arterial augmentation index adjusted for a heart rate of 75 (AI75) and reactive hyperemia index (RHI) were determined immediately before, and 30, 60, and 90 minutes after exertion. Low-dose aspirin was associated with lower AI75 (-15.25±9.25 vs -8.08±10.70, p=0.014) but not RHI. On repeated measures analysis, treatment with low-dose aspirin before, but not single-dose aspirin after exertion, was associated with lower AI75 following exertional heat stress (p=0.018). Low-dose aspirin improved peripheral arterial stiffness and wave reflection but not endothelial function in firefighters. © The Author(s) 2015.
Caffeine and theanine exert opposite effects on attention under emotional arousal.
Giles, Grace E; Mahoney, Caroline R; Brunyé, Tad T; Taylor, Holly A; Kanarek, Robin B
2017-01-01
Tea is perceived as more relaxing than coffee, even though both contain caffeine. L-theanine in tea may account for the difference. Consumed together, caffeine and theanine exert similar cognitive effects to that of caffeine alone, but exert opposite effects on arousal, in that caffeine accentuates and theanine mitigates physiological and felt stress responses. We evaluated whether caffeine and theanine influenced cognition under emotional arousal. Using a double-blind, repeated-measures design, 36 participants received 4 treatments (200 mg caffeine + 0 mg theanine, 0 mg caffeine + 200 mg theanine, 200 mg caffeine + 200 mg theanine, 0 mg caffeine + 0 mg theanine) on separate days. Emotional arousal was induced by highly arousing negative film clips and pictures. Mood, salivary cortisol, and visual attention were evaluated. Caffeine accentuated global processing of visual attention on the hierarchical shape task (p < 0.05), theanine accentuated local processing (p < 0.05), and the combination did not differ from placebo. Caffeine reduced flanker conflict difference scores on the Attention Network Test (p < 0.05), theanine increased difference scores (p < 0.05), and the combination did not differ from placebo. Thus, under emotional arousal, caffeine and theanine exert opposite effects on certain attentional processes, but when consumed together, they counteract the effects of each other.
Load variation effects on the pressure fluctuations exerted on a Kaplan turbine runner
NASA Astrophysics Data System (ADS)
Amiri, K.; Mulu, B.; Raisee, M.; Cervantes, M. J.
2014-03-01
Introduction of intermittent electricity production systems like wind power and solar systems to electricity market together with the consumption-based electricity production resulted in numerous start/stops, load variations and off-design operation of water turbines. The hydropower systems suffer from the varying loads exerted on the stationary and rotating parts of the turbines during load variations which they are not designed for. On the other hand, investigations on part load operation of single regulated turbines, i.e., Francis and propeller, proved the formation of rotating vortex rope (RVR) in the draft tube. The RVR induces oscillating flow both in plunging and rotating modes which results in oscillating force with two different frequencies on the runner blades, bearings and other rotating parts of the turbine. The purpose of this study is to investigate the effect of transient operations on the pressure fluctuations on the runner and mechanism of the RVR formation/mitigation. Draft tube and runner blades of the Porjus U9 model, a Kaplan turbine, were equipped with pressure sensors. The model was run in off-cam mode during different load variation conditions to check the runner performance under unsteady condition. The results showed that the transients between the best efficiency point and the high load happens in a smooth way while transitions to/from the part load, where rotating vortex rope (RVR) forms in the draft tube induces high level of fluctuations with two frequencies on the runner; plunging and rotating mode of the RVR.
Physiological and psychological responses to outdoor vs. laboratory cycling.
Mieras, Molly E; Heesch, Matthew W S; Slivka, Dustin R
2014-08-01
The purpose of this study was to determine the physiological and psychological responses to laboratory vs. outdoor cycling. Twelve recreationally trained male cyclists participated in an initial descriptive testing session and 2 experimental trials consisting of 1 laboratory and 1 outdoor session, in a randomized order. Participants were given a standardized statement instructing them to give the same perceived effort for both the laboratory and outdoor 40-km trials. Variables measured include power output, heart rate (HR), core temperature, skin temperature, body weight, urine specific gravity (USG), Rating of Perceived Exertion (RPE), attentional focus, and environmental conditions. Wind speed was higher in the outdoor trial than in the laboratory trial (2.5 ± 0.6 vs. 0.0 ± 0.0 m·s-1, p = 0.02) whereas all other environmental conditions were similar. Power output (208.1 ± 10.2 vs. 163.4 ± 11.8 W, respectively, p < 0.001) and HR (152 ± 4 and 143 ± 6 b·min-1, respectively, p = 0.04) were higher in the outdoor trial than in the laboratory trial. Core temperature was similar, whereas skin temperature was cooler during the outdoor trial than during the laboratory trial (31.4 ± 0.3 vs. 33.0 ± 0.2° C, respectively, p < 0.001), thus creating a larger thermal gradient between the core and skin outdoors. No significant differences in body weight, USG, RPE, or attentional focus were observed between trials. These data indicate that outdoor cycling allows cyclists to exercise at a higher intensity than in laboratory cycling, despite similar environmental conditions and perceived exertion. In light of this, cyclists may want to ride at a higher perceived exertion in indoor settings to acquire the same benefit as they would from an outdoor ride.
Dissociation between dorsal and ventral hippocampal theta oscillations during decision-making.
Schmidt, Brandy; Hinman, James R; Jacobson, Tara K; Szkudlarek, Emily; Argraves, Melissa; Escabí, Monty A; Markus, Etan J
2013-04-03
Hippocampal theta oscillations are postulated to support mnemonic processes in humans and rodents. Theta oscillations facilitate encoding and spatial navigation, but to date, it has been difficult to dissociate the effects of volitional movement from the cognitive demands of a task. Therefore, we examined whether volitional movement or cognitive demands exerted a greater modulating factor over theta oscillations during decision-making. Given the anatomical, electrophysiological, and functional dissociations along the dorsal-ventral axis, theta oscillations were simultaneously recorded in the dorsal and ventral hippocampus in rats trained to switch between place and motor-response strategies. Stark differences in theta characteristics were found between the dorsal and ventral hippocampus in frequency, power, and coherence. Theta power increased in the dorsal, but decreased in the ventral hippocampus, during the decision-making epoch. Interestingly, the relationship between running speed and theta power was uncoupled during the decision-making epoch, a phenomenon limited to the dorsal hippocampus. Theta frequency increased in both the dorsal and ventral hippocampus during the decision epoch, although this effect was greater in the dorsal hippocampus. Despite these differences, ventral hippocampal theta was responsive to the navigation task; theta frequency, power, and coherence were all affected by cognitive demands. Theta coherence increased within the dorsal hippocampus during the decision-making epoch on all three tasks. However, coherence selectively increased throughout the hippocampus (dorsal to ventral) on the task with new hippocampal learning. Interestingly, most results were consistent across tasks, regardless of hippocampal-dependent learning. These data indicate increased integration and cooperation throughout the hippocampus during information processing.
Effect of Stimulant Medication Use by Children with ADHD on Heart Rate and Perceived Exertion
ERIC Educational Resources Information Center
Mahon, Anthony D.; Woodruff, Megan E.; Horn, Mary P.; Marjerrison, Andrea D.; Cole, Andrew S.
2012-01-01
The effect of stimulant medication use by children with attention deficit/hyperactivity disorder (ADHD) on the rating of perceived exertion (RPE)--heart rate (HR) relationship was examined. Children with ADHD (n = 20; 11.3 [plus or minus] 1.8 yrs) and children without ADHD (n = 25; 11.2 [plus or minus] 2.1 yrs) were studied. Children with ADHD…
Evaluative pressure overcomes perceptual load effects.
Normand, Alice; Autin, Frédérique; Croizet, Jean-Claude
2015-06-01
Perceptual load has been found to be a powerful bottom-up determinant of distractibility, with high perceptual load preventing distraction by any irrelevant information. However, when under evaluative pressure, individuals exert top-down attentional control by giving greater weight to task-relevant features, making them more distractible from task-relevant distractors. One study tested whether the top-down modulation of attention under evaluative pressure overcomes the beneficial bottom-up effect of high perceptual load on distraction. Using a response-competition task, we replicated previous findings that high levels of perceptual load suppress task-relevant distractor response interference, but only for participants in a control condition. Participants under evaluative pressure (i.e., who believed their intelligence was assessed) showed interference from task-relevant distractor at all levels of perceptual load. This research challenges the assumptions of the perceptual load theory and sheds light on a neglected determinant of distractibility: the self-relevance of the performance situation in which attentional control is solicited.
Innate Immunity and Inflammation Post-Stroke: An α7-Nicotinic Agonist Perspective
Neumann, Silke; Shields, Nicholas J.; Balle, Thomas; Chebib, Mary; Clarkson, Andrew N.
2015-01-01
Stroke is one of the leading causes of death and long-term disability, with limited treatment options available. Inflammation contributes to damage tissue in the central nervous system across a broad range of neuropathologies, including Alzheimer’s disease, pain, Schizophrenia, and stroke. While the immune system plays an important role in contributing to brain damage produced by ischemia, the damaged brain, in turn, can exert a powerful immune-suppressive effect that promotes infections and threatens the survival of stroke patients. Recently the cholinergic anti-inflammatory pathway, in particular its modulation using α7-nicotinic acetylcholine receptor (α7-nAChR) ligands, has shown potential as a strategy to dampen the inflammatory response and facilitate functional recovery in stroke patients. Here we discuss the current literature on stroke-induced inflammation and the effects of α7-nAChR modulators on innate immune cells. PMID:26690125
Innate Immunity and Inflammation Post-Stroke: An α7-Nicotinic Agonist Perspective.
Neumann, Silke; Shields, Nicholas J; Balle, Thomas; Chebib, Mary; Clarkson, Andrew N
2015-12-04
Stroke is one of the leading causes of death and long-term disability, with limited treatment options available. Inflammation contributes to damage tissue in the central nervous system across a broad range of neuropathologies, including Alzheimer's disease, pain, Schizophrenia, and stroke. While the immune system plays an important role in contributing to brain damage produced by ischemia, the damaged brain, in turn, can exert a powerful immune-suppressive effect that promotes infections and threatens the survival of stroke patients. Recently the cholinergic anti-inflammatory pathway, in particular its modulation using α7-nicotinic acetylcholine receptor (α7-nAChR) ligands, has shown potential as a strategy to dampen the inflammatory response and facilitate functional recovery in stroke patients. Here we discuss the current literature on stroke-induced inflammation and the effects of α7-nAChR modulators on innate immune cells.
Galvan, Antonella; Ioannidis, John P.A.; Dragani, Tommaso A.
2010-01-01
Genome-wide association studies (GWAS) using population-based designs have identified many genetic loci associated with risk of a range of complex diseases including cancer; however, each locus exerts a very small effect and most heritability remains unexplained. Family-based pedigree studies have also suggested tentative loci linked to increased cancer risk, often characterized by pedigree-specificity. However, a comparison between the results of population-and those of family-based studies shows little concordance. Explanations for this unidentified genetic ‘dark matter’ of cancer include phenotype ascertainment issues, limited power, gene-gene and gene-environment interactions, population heterogeneity, parent-of-origin-specific effects, rare and unexplored variants. Many of these reasons converge towards the concept of genetic heterogeneity that might implicate hundreds of genetic variants in regulating cancer risk. Dissecting the dark matter is a challenging task. Further insights can be gained from both population association and pedigree studies. PMID:20106545
Mesmer minus magic: hypnosis and modern medicine.
Spiegel, David
2002-10-01
The implications and effects of the French commission that passed judgment on Mesmer's work is examined in light of the pioneering role of hypnosis as the first Western conception of a psychotherapy, the ancient philosophical debate between idealism and empiricism, and the conflict in modern medicine between biotechnological emphasis on cure and the need for care as many previously terminal illnesses are converted to chronic diseases. The panel's report is interpreted as negative about the literal theory of animal magnetism but actually supportive of the potential therapeutic power of suggestion and "positive thinking." This aspect of hypnosis is described as a forerunner of modern cognitive therapies of depression and other illnesses. The panel exerted a constructive effect in applying scientific method and rigorous evaluation to hypnotic treatment, an application of Enlightenment philosophy that presaged the Flexner era in modern medicine. Both hypnosis and medicine ultimately benefited.
Tanaka, Daichi; Tsukamoto, Hayato; Suga, Tadashi; Takenaka, Saki; Hamaoka, Takafumi; Hashimoto, Takeshi; Isaka, Tadao
2018-05-26
Acute aerobic exercise improves inhibitory control (IC). This improvement is often associated with increases in perceived exertion during exercise. However, listening to music during aerobic exercise mitigates an exercise-induced increase in perceived exertion. Thus, it is hypothesized that such effects of music may interfere with exercise-induced improvements in IC. To test this hypothesis, we examined the effect of music on post-exercise IC improvements that were induced by moderate-intensity exercise. Fifteen healthy young men performed cycle ergometer exercise with music or non-music. The exercise was performed using a moderate-intensity of 60% of VO 2 peak for 30 min. The music condition was performed while listening to self-selected music. The non-music condition involved no music. To evaluate IC, the Stroop task was administered before exercise, immediately after exercise, and during the 30-min post-exercise recovery period. The rate of perceived exertion immediately before moderate-intensity exercise completed was significantly lower in music condition than in non-music condition. The IC significantly improved immediately after exercise and during the post-exercise recovery period compared to before exercise in both music and non-music conditions. The post-exercise IC improvements did not significantly differ between the two conditions. These findings indicate that self-selected music-induced mitigation of the increase in perceived exertion during moderate-intensity exercise dose not interfere with exercise-induced improvements in IC. Therefore, we suggest that listening to music may be a beneficial strategy in mitigating the increase in perceived exertion during aerobic exercise without decreasing the positive effects on IC. Copyright © 2018 Elsevier Inc. All rights reserved.
From damselflies to pterosaurs: how burst and sustainable flight performance scale with size.
Marden, J H
1994-04-01
Recent empirical data for short-burst lift and power production of flying animals indicate that mass-specific lift and power output scale independently (lift) or slightly positively (power) with increasing size. These results contradict previous theory, as well as simple observation, which argues for degradation of flight performance with increasing size. Here, empirical measures of lift and power during short-burst exertion are combined with empirically based estimates of maximum muscle power output in order to predict how burst and sustainable performance scale with body size. The resulting model is used to estimate performance of the largest extant flying birds and insects, along with the largest flying animals known from fossils. These estimates indicate that burst flight performance capacities of even the largest extinct fliers (estimated mass 250 kg) would allow takeoff from the ground; however, limitations on sustainable power output should constrain capacity for continuous flight at body sizes exceeding 0.003-1.0 kg, depending on relative wing length and flight muscle mass.
Perspective: physician leaders and their bases of power: common and disparate elements.
Gabel, Stewart
2012-02-01
Physicians hold numerous types of leadership positions in academic, executive, and/or clinical environments. To be successful, physician leaders must exert power, or social influence, as power is conceptualized in social psychology. The power of leaders accrues through their positions, expertise, or other factors, such as communication abilities or their ability to influence others to identify with the vision they espouse. This article discusses the types of leadership roles that physicians play and the power types they must apply in these roles. Crossing all leadership roles are a series of necessary personal characteristics and interpersonal competencies that result in what has been called "referent power," a more subtle form of social influence that is crucial for success regardless of position. Leadership training that includes practice in cultivating these personal characteristics and interpersonal competencies should be an essential component of medical and graduate medical education. Studying the types and nature of power also would be a valuable contribution to courses on professionalism in medical practice. Examples are provided of the types and uses of power that may be applied in the various leadership roles that physicians hold.
Strength capability while kneeling.
Haslegrave, C M; Tracy, M F; Corlett, E N
1997-12-01
Work sometimes has to be carried out kneeling, particularly where jobs are performed in confined spaces as is common for miners, aircraft baggage handlers and maintenance workers. In order to assess the risks in performing forceful tasks under such conditions, data is needed on strength capabilities of kneeling subjects. A study was undertaken to measure isometric strength in single-handed exertions for male subjects and to investigate the effects on this of task layout factors (direction of force exertion, reach distance, height of the workpiece and orientation relative to the subject's sagittal plane). The data has been tabulated to show the degree to which strength may be reduced in different situations and analysis of the task factors showed their influence to be complex with direction of exertion and reach distance having the greatest effect. The results also suggest that exertions are weaker when subjects are kneeling on two knees than when kneeling on one knee, although this needs to be confirmed by direct experimental comparison.
Mengelkoch, Larry J; Highsmith, M Jason; Morris, Merry L
2014-09-01
Mobility devices for dancers with physical mobility impairments have previously been limited to traditional manual or power wheelchairs. The hands-free torso-controlled mobility chair is a unique powered mobility device which allows greater freedom and expression of movement of the trunk and upper extremities. This study compared differences in energy expenditure during a standardized dance activity using three mobility devices: the hands-free torso-controlled mobility chair, a manual sports wheelchair with hand-arm control, and an electric power chair with hand-joystick control. An experienced dancer with C7 incomplete spinal cord injury (SCI) and an experienced able-bodied dancer were recruited for testing. Three measurement trials were obtained for each chair per subject. Oxygen uptake (VO2) and heart rate (HR) were measured continuously during the dance activity. Immediately following the dance activity, subjects rated perceived exertion. Significant differences (p ≤ 0.05) and similar linear patterns in VO2 and HR responses were observed between chairs for both dancers. When the hands-free mobility chair was used, the dance activity required a moderate level of energy expenditure compared to the manual sports chair or electric power chair for both dancers. Higher ratings of perceived exertion were observed in the manual chair compared to the other chairs for the dancer with SCI, but were similar between chairs for the able-bodied dancer. These results suggest that for a dancer with high-level SCI, the hands-free torso-controlled mobility chair may offer improved freedom and expressive movement possibilities and is an energy-efficient mobility device.
Mechanisms underlying very-low-frequency RR-interval oscillations in humans
NASA Technical Reports Server (NTRS)
Taylor, J. A.; Carr, D. L.; Myers, C. W.; Eckberg, D. L.
1998-01-01
BACKGROUND: Survival of post-myocardial infarction patients is related inversely to their levels of very-low-frequency (0.003 to 0.03 Hz) RR-interval variability. The physiological basis for such oscillations is unclear. In our study, we used blocking drugs to evaluate potential contributions of sympathetic and vagal mechanisms and the renin-angiotensin-aldosterone system to very-low-frequency RR-interval variability in 10 young healthy subjects. METHODS AND RESULTS: We recorded RR intervals and arterial pressures during three separate sessions, with the patient in supine and 40 degree upright tilt positions, during 20-minute frequency (0.25 Hz) and tidal volume-controlled breathing after intravenous injections: saline (control), atenolol (0.2 mg/kg, beta-adrenergic blockade), atropine sulfate (0.04 mg/kg, parasympathetic blockade), atenolol and atropine (complete autonomic blockade), and enalaprilat (0.02 mg/kg, ACE blockade). We integrated fast Fourier transform RR-interval spectral power at very low (0.003 to 0.03 Hz), low (0.05 to 0. 15 Hz), and respiratory (0.2 to 0.3 Hz) frequencies. Beta-adrenergic blockade had no significant effect on very-low- or low-frequency RR-interval power but increased respiratory frequency power 2-fold. ACE blockade had no significant effect on low or respiratory frequency RR-interval power but modestly (approximately 21%) increased very-low-frequency power in the supine (but not upright tilt) position (P<0.05). The most profound effects were exerted by parasympathetic blockade: Atropine, given alone or with atenolol, abolished nearly all RR-interval variability and decreased very-low-frequency variability by 92%. CONCLUSIONS: Although very-low-frequency heart period rhythms are influenced by the renin-angiotensin-aldosterone system, as low and respiratory frequency RR-interval rhythms, they depend primarily on the presence of parasympathetic outflow. Therefore the prognostic value of very-low-frequency heart period oscillations may derive from the fundamental importance of parasympathetic mechanisms in cardiovascular health.
Electromagnetic attachment mechanism
NASA Technical Reports Server (NTRS)
Monford, Leo G., Jr. (Inventor)
1992-01-01
An electromagnetic attachment mechanism is disclosed for use as an end effector of a remote manipulator system. A pair of electromagnets, each with a U-shaped magnetic core with a pull-in coil and two holding coils, are mounted by a spring suspension system on a base plate of the mechanism housing with end pole pieces adapted to move through openings in the base plate when the attractive force of the electromagnets is exerted on a strike plate of a grapple fixture affixed to a target object. The pole pieces are spaced by an air gap from the strike plate when the mechanism first contacts the grapple fixture. An individual control circuit and power source is provided for the pull-in coil and one holding coil of each electromagnet. A back-up control circuit connected to the two power sources and a third power source is provided for the remaining holding coils. When energized, the pull-in coils overcome the suspension system and air gap and are automatically de-energized when the pole pieces move to grapple and impose a preload force across the grapple interface. A battery backup is a redundant power source for each electromagnet in each individual control circuit and is automatically connected upon failure of the primary source. A centerline mounted camera and video monitor are used in cooperation with a target pattern on the reflective surface of the strike plate to effect targeting and alignment.
2013-04-01
in the region, particularly with Afghanistan and India . This report demonstrates the lack of links between madāris and terrorism by analyzing...standardization originated not from the command of the Emperor but by Mulla Nizam Uddin Sihalvi of the Farangi Mahall madrassah near Lucknow, India in the...As the East India Company exerted more and more power over the subcontinent, culminating in the 1857 India rebellion, this aspect of the
ERIC Educational Resources Information Center
Barakos, Elisabeth
2016-01-01
In this paper, I examine how language policy acts as a means of both empowering the Welsh language and the minority language worker and as a means of exerting power over them. For this purpose, the study focuses on a particular site: private sector businesses in Wales. Therein, I trace two major discursive processes: first, the Welsh Government's…
Lauren P. Waller; Ragan M. Callaway; John N. Klironomos; Yvette K. Ortega; John L. Maron
2016-01-01
1. Arbuscular mycorrhizal (AM) fungi can exert a powerful influence on the outcome of plantâplant competition. Since some exotic plants interact differently with soil biota such as AM fungi in their new range, range-based shifts in AM responsiveness could shift competitive interactions between exotic and resident plants, although this remains poorly studied. 2. We...
ERIC Educational Resources Information Center
Hargreaves, Andy
This book examines the personal, moral, cultural, and political dimensions of teaching in the context of rapid and far-reaching change within teachers' work and in the world beyond it. The chapters in Part One examine the powerful forces for change in society and how those forces are exerting pressure on existing institutions. Issues such as the…
ERIC Educational Resources Information Center
Debreli, Emre
2016-01-01
It is often said that beliefs determine the ways teachers think and act in classrooms. There is now strong evidence that teachers' beliefs are formed during their previous education as students, and that they exert a powerful influence throughout their careers. However, only little has yet been done on the teacher education programmes' influence…
ERIC Educational Resources Information Center
Asian Art Museum of San Francisco, CA.
Tomb art provides an invaluable window into China's history and culture. The understanding that spirits of dead ancestors can exert power and influence over the lives of their descendants has been a central tenet of the Chinese belief system, propelling the culture into practices ensuring the provision of comfort and status to the deceased in…
1. GUEST HOUSE KNOWN AS 'THE LODGE' REPORTEDLY BUILT TO ...
1. GUEST HOUSE KNOWN AS 'THE LODGE' REPORTEDLY BUILT TO BE USED BY J.D. ROSS ON HIS VISITS TO THE SKAGIT PROJECT. DURING THE 1930S THE U.S. FOREST SERVICE EXERTED A STONG INFLUENCE ON BUILDING STYLES FOR RESIDENCES AT THE SKAGIT PROJECT, 1989. - Skagit Power Development, Skagit River & Newhalem Creek Hydroelectric Project, On Skagit River, Newhalem, Whatcom County, WA
Arratibel-Imaz, Iñaki; Calleja-González, Julio; Emparanza, Jose Ignacio; Terrados, Nicolas; Mjaanes, Jeffrey M; Ostojic, Sergej M
2016-01-01
The calculation of exertion intensity, in which a change is produced in the metabolic processes which provide the energy to maintain physical work, has been defined as the anaerobic threshold (AT). The direct calculation of maximal lactate steady state (MLSS) would require exertion intensities over a long period of time and with sufficient rest periods which would prove significantly difficult for daily practice. Many protocols have been used for the indirect calculation of MLSS. The aim of this study is to determine if the results of measurements with 12 different AT calculation methods and calculation software [Keul, Simon, Stegmann, Bunc, Dickhuth (TKM and WLa), Dmax, Freiburg, Geiger-Hille, Log-Log, Lactate Minimum] can be used interchangeably, including the method of the fixed threshold of Mader/OBLA's 4 mmol/l and then to compare them with the direct measurement of MLSS. There were two parts to this research. Phase 1: results from 162 exertion tests chosen at random from the 1560 tests. Phase 2: sixteen athletes (n = 16) carried out different tests on five consecutive days. There was very high concordance among all the methods [intraclass correlation coefficient (ICC) > 0.90], except Log-Log in relation to the Stegamnn, Dmax, Dickhuth-WLa and Geiger-Hille. The Dickhuth-TKM showed a high tendency towards concordance, with Dmax (2.2 W) and Dickhuth-WLa (0.1 W). The Dickhuth-TKM method presented a high tendency to concordance with Dickhuth-WLa (0.5 W), Freiburg (7.4 W), MLSS (2.0 W), Bunc (8.9 W), Dmax (0.1 W). The calculation of MLSS power showed a high tendency to concordance, with Dickhuth-TKM (2 W), Dmax (2.1 W), Dickhuth-WLa (1.5 W). The fixed threshold of 4 mmol/l or OBLA produces slightly different and higher results than those obtained with all the methods analyzed, including MLSS, meaning an overestimation of power in the individual anaerobic threshold. The Dickhuth-TKM, Dmax and Dickhuth-WLa methods defined a high concordance on a cycle ergometer. Dickhuth-TKM, Dmax, Dickhuth-WLa described a high concordance with the power calculated to know the MLSS.
Chen, Andrew C N; Liu, Feng-Jun; Wang, Li; Arendt-Nielsen, Lars
2006-02-15
This study determined: (a) if acupuncture stimulation at a traditional site might modulate ongoing EEG as compared with stimulation of a control site; (b) if high-frequency vs. low-frequency stimulation could exert differential effects of acupuncture; (c) if the observed effects of acupuncture were specific to certain EEG bands; and (d) if the acupuncture effect could be isolated at a specific scalp field, with its putative underlying intracranial source. Twelve healthy male volunteers (age range 22-35) participated in two experimental sessions separated by 1 week, which involved transcutaneous acupoint stimulation at selected acupoint (Li 4, HeGu) vs. a mock point at the fourth interosseous muscle area on the left hand in high (HF: 100 Hz) vs. low-frequency (LF: 2 Hz) stimulation by counter-balanced order. 124-ch EEG data were used to analyze the Delta, Theta, Alpha-1, Alpha-2, Beta, and Gamma bands. The absolute EEG powers (muv2) at focal maxima across three stages (baseline, stimulation, post) were examined by two-way (condition, stage) repeated measures ANOVA. The activity of the Theta power significantly decreased (P = 0.02), compared with control during HF but not LF stimulation at acupoint stimulation, however, there was no study effect at the mock point. A decreased Theta EEG power was prominent at the frontal midline sites (FCz, Fz) and the contralateral right hemisphere front site (FCC2h). In contrast, the Theta power of low-frequency stimulation showed an increase from the baseline as those in both controlled mock point stimulations. The observed high-frequency acupoint stimulation effects of Theta EEG were only present during, but not after, simulation. The topographic Theta activity was tentatively identified to originate from the intracranial current source in cingulate cortex, likely ACC. It is likely that short-term cortical plasticity occurs during high-frequency but not low-frequency stimulation at the HeGu point, but not mock point. We suggest that HeGu acupuncture stimulation modulates limbic cingulum by a frequency modulation mode, which then may damp nociceptive processing in the brain.
Wu, Wenzheng; Ye, Wenli; Wu, Zichao; Geng, Peng; Wang, Yulei; Zhao, Ji
2017-01-01
The success of the 3D-printing process depends upon the proper selection of process parameters. However, the majority of current related studies focus on the influence of process parameters on the mechanical properties of the parts. The influence of process parameters on the shape-memory effect has been little studied. This study used the orthogonal experimental design method to evaluate the influence of the layer thickness H, raster angle θ, deformation temperature Td and recovery temperature Tr on the shape-recovery ratio Rr and maximum shape-recovery rate Vm of 3D-printed polylactic acid (PLA). The order and contribution of every experimental factor on the target index were determined by range analysis and ANOVA, respectively. The experimental results indicated that the recovery temperature exerted the greatest effect with a variance ratio of 416.10, whereas the layer thickness exerted the smallest effect on the shape-recovery ratio with a variance ratio of 4.902. The recovery temperature exerted the most significant effect on the maximum shape-recovery rate with the highest variance ratio of 1049.50, whereas the raster angle exerted the minimum effect with a variance ratio of 27.163. The results showed that the shape-memory effect of 3D-printed PLA parts depended strongly on recovery temperature, and depended more weakly on the deformation temperature and 3D-printing parameters. PMID:28825617
Pharmacodynamic studies of vancomycin, metronidazole and fusidic acid against Clostridium difficile.
Odenholt, Inga; Walder, Mats; Wullt, Marlene
2007-01-01
Pharmacodynamic studies of antibiotics have attracted great interest in recent years. However, studies on the pharmacodynamics of different antibiotics against Clostridium difficile are scarce. The postantibiotic effects (PAE) and the postantibiotic sub-minimum inhibitory concentration (MIC) effects (PA SME) of vancomycin, metronidazole and fusidic acid were investigated by viable counts against three different strains of C. difficile. The killing rate and extent of the three antibiotics against the same strains were also studied by adding 2, 4, 8, 16 and 32x MIC of the three antibiotics, respectively. Metronidazole exerted a very rapid bactericidal effect at concentrations of 8x MIC and above against all three strains investigated. Vancomycin gave overall less kill in comparison to metronidazole and was bacteriostatic against two of the three strains. Fusidic acid exerted a concentration-dependent killing against two of the strains. Vancomycin exerted short PAEs and PA SMEs against all three strains. Significantly longer PAEs and PA SMEs were noted for fusidic acid. Metronidazole gave similar short PAEs like vancomycin but longer PA SMEs were noted against two of the investigated strains. Metronidazole exerted the most prominent bactericidal effect greater than fusidic acid and greater than vancomycin. Fusidic acid gave overall the longest PAEs and PA SMEs greater than metronidazole and greater than vancomycin. Copyright 2007 S. Karger AG, Basel.
Dworkin, Shari L; Zakaras, Jennifer M; Campbell, Chadwick; Wilson, Patrick; Grisham, Kirk; Chakravarty, Deepalika; Neilands, Torsten B; Hoff, Colleen
2017-09-01
Research is clear that power differentials between women and men shape women's human immunodeficiency virus (HIV) risks; however, little research has attempted to examine power differentials within same-sex male (SSM) couples and whether these influence sexual risk outcomes. To produce the first quantitative scale that measures power in SSM relationships, the current work was a Phase 1 qualitative study that sought to understand domains of relationship power and how power operated in the relationship among 48 Black, White, and interracial (Black-White) SSM couples recruited from San Francisco and New York. Interview domains were focused on definitions of power and perceptions of how power operated in the relationship. Findings revealed that couples described power in three key ways: as power exerted over a partner through decision-making dominance and relationship control; as power to accomplish goals through personal agency; and as couple-level power. In addition, men described ways that decision-making dominance and relationship control could be enacted in the relationship-through structural resources, emotional and sexual influence, and gender norm expectations. We discuss the implications of these findings for sexual risks and HIV care and treatment with SSM couples that are focused on closing gaps in power.
Defining the Focus of Attention: Effects of Attention on Perceived Exertion and Fatigue
Lohse, Keith R.; Sherwood, David E.
2011-01-01
This manuscript presents two experiments designed to explore the effects of attention on perceived exertion and time to failure in a fatiguing athletic task. There were two major motivating factors for these experiments. First, there are few studies evaluating attentional focus effects in endurance tasks and, second, there is a lack of integration between studies of attentional focus as external/internal (e.g., Wulf, 2007a) compared to associative/dissociative (e.g., Stevinson and Biddle, 1998). In Experiment 1, we used a fatiguing wall-sit posture (essentially a complex, isometric task) to compare two different types of external attention with an internal focus on the position of the legs. An external focus (regardless of type) increased the time taken to failure and reduced perceived exertion. In Experiment 2, we manipulated subjects’ expectancy of fatigue to test the interaction of attention and expectancy (both top-down factors) in this highly fatiguing task. Previous theories of attention during endurance tasks have suggested that as fatigue/pain increase, bottom-up factors begin to dominate subjects’ attention. While this may be true, Experiment 2 showed that even in a highly fatiguing task, attentional strategies, and expectancies affected the time to failure and perceived exertion. PMID:22102843
Savani, Krishna; Job, Veronika
2017-10-01
The strength model of self-control has been predominantly tested with people from Western cultures. The present research asks whether the phenomenon of ego-depletion generalizes to a culture emphasizing the virtues of exerting mental self-control in everyday life. A pilot study found that whereas Americans tended to believe that exerting willpower on mental tasks is depleting, Indians tended to believe that exerting willpower is energizing. Using dual task ego-depletion paradigms, Studies 1a, 1b, and 1c found reverse ego-depletion among Indian participants, such that participants exhibited better mental self-control on a subsequent task after initially working on strenuous rather than nonstrenuous cognitive tasks. Studies 2 and 3 found that Westerners exhibited the ego-depletion effect whereas Indians exhibited the reverse ego-depletion effect on the same set of tasks. Study 4 documented the causal effect of lay beliefs about whether exerting willpower is depleting versus energizing on reverse ego-depletion with both Indian and Western participants. Together, these studies reveal the underlying basis of the ego-depletion phenomenon in culturally shaped lay theories about willpower. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Protection against atherogenesis with the polymer drag-reducing agent Separan AP-30.
Faruqui, F I; Otten, M D; Polimeni, P I
1987-03-01
The inhibitory effect of Separan AP-30, an anionic polyacrylamide, on atherosclerotic plaque formation in aortas of rabbits on a high (2%) cholesterol diet was tested over a period extending from 37 to 170 days. Atherogenesis was quantified morphometrically by application of a computer-assisted image analysis of histologic cross sections of the aorta. The area of vessel wall-atheroma interface, fraction of lumen occluded, and other indexes of atherogenesis were measured in each of 26 segments of aorta excised from the animals, half of which were administered injections (intravenous) of Separan three times a week. Regression analysis of the morphometric data indicates that the polyelectrolyte exerts a powerful antiatherogenic effect in all regions of the aorta, inhibiting the formation of plaque mass to less than half in the aortic arch and about one-fifth in the descending aorta as compared with the aortic plaque masses in untreated rabbits. Results are compatible with the suggestion that a novel hemodynamic principle in vivo, polymer drag reduction, might be effectively applied against atherosclerosis.
Dose-response relationships for resetting of human circadian clock by light
NASA Technical Reports Server (NTRS)
Boivin, D. B.; Duffy, J. F.; Kronauer, R. E.; Czeisler, C. A.
1996-01-01
Since the first report in unicells, studies across diverse species have demonstrated that light is a powerful synchronizer which resets, in an intensity-dependent manner, endogenous circadian pacemakers. Although it is recognized that bright light (approximately 7,000 to 13,000 lux) is an effective circadian synchronizer in humans, it is widely believed that the human circadian pacemaker is insensitive to ordinary indoor illumination (approximately 50-300 lux). It has been proposed that the relationship between the resetting effect of light and its intensity follows a compressive nonlinear function, such that exposure to lower illuminances still exerts a robust effect. We therefore undertook a series of experiments which support this hypothesis and report here that light of even relatively low intensity (approximately 180 lux) significantly phase-shifts the human circadian pacemaker. Our results clearly demonstrate that humans are much more sensitive to light than initially suspected and support the conclusion that they are not qualitatively different from other mammals in their mechanism of circadian entrainment.
Calorigenic effect of glucagon and catecholamines in king penguin chicks.
Barre, H; Rouanet, J L
1983-06-01
The calorigenic action of glucagon and catecholamine infusion was evaluated in winter-acclimatized king penguin chicks at 20 and 0 degrees C ambient temperature (Ta). At Ta = 20 degrees C the mean increase in metabolic rate was 0.73 W . kg-1 for epinephrine (80 micrograms . kg-1), 0.42 W . kg-1 for norepinephrine (150 micrograms . kg-1), and 1.16 W . kg-1 for glucagon (0.75 micrograms . kg-1); i.e., respectively 30, 17, and 47% of the control value. The maximum response to glucagon reached 89% over control. At Ta = 0 degrees C, for the same glucagon infusion, the mean increase in specific metabolic rate was 0.84 W . kg-1, 27% of control rate. In the cold, glucagon infusion inhibited shivering and substituted its calorigenic action, resulting in a less apparent effect. In contrast with the negligible effect of catecholamines, glucagon infused at low doses exerted a powerful calorigenic action in young king penguins and could be considered as a possible nonshivering thermogenesis mediator.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ogawa, E.; Suzuki, S.; Tsuzuki, H.
Mice were subcutaneoulsy injected with Sr/sup 90/ or Sr/sup 85/, and effects of various drugs on their 3-day excretion and retention on the 4th day were investigated. Among chelating agents, NaCa citrate, NaMg citrate, NaSr citrate, Achromycin (or tetracycline), and aspartic MgK (alone or in combination with NH/sub 4/Cl) displayed Sr-eliminating effects. ATP increased only the excretion without diminishing the retention in bone. EDTA, DTPA, BADE, tricarballylate, Na citrate and NaPb citrate were not effective. Among salts, Mg salt, sulfite, and thiosulfate were effective in eliminating Sr. The last exerted a greater effect when given concurrently with Mg, Ca, ormore » Sr salt. Ca and Sr salt exerted no effect, and ammonium chloride promoted only urinary secretion, not extending to local or total excretion. Such salts as induce alkalosis conversely exerted inhibitory effects. Among hormones, glucocorticoids had Sreliminating effects. TSH was effective, and antithyroidal drugs conversely seemed to have excretion-diminishing effects. Among vitamins, cocarboxylase increased Sr excretion, but did not decrease the retention in bone. Also metabolic inhibitors were ineffective, and NaF conversely increased bone deposition of Sr. Among diuretics, SHdrugs, and weak chelating agents, there were no effective drugs. (JAIF)« less
Independent effects of relevance and arousal on deductive reasoning.
Caparos, Serge; Blanchette, Isabelle
2017-08-01
Emotional content can have either a deleterious or a beneficial impact on logicality. Using standard deductive-reasoning tasks, we tested the hypothesis that the interplay of two factors - personal relevance and arousal - determines the nature of the effect of emotional content on logicality. Arousal was assessed using measures of skin conductance. Personal relevance was manipulated by asking participants to reason about semantic contents linked to an emotional event that they had experienced or not. Findings showed that (1) personal relevance exerts a positive effect on logicality while arousal exerts a negative effect, and that (2) these effects are independent of each other.
Braking System for Wind Turbines
NASA Technical Reports Server (NTRS)
Krysiak, J. E.; Webb, F. E.
1987-01-01
Operating turbine stopped smoothly by fail-safe mechanism. Windturbine braking systems improved by system consisting of two large steel-alloy disks mounted on high-speed shaft of gear box, and brakepad assembly mounted on bracket fastened to top of gear box. Lever arms (with brake pads) actuated by spring-powered, pneumatic cylinders connected to these arms. Springs give specific spring-loading constant and exert predetermined load onto brake pads through lever arms. Pneumatic cylinders actuated positively to compress springs and disengage brake pads from disks. During power failure, brakes automatically lock onto disks, producing highly reliable, fail-safe stops. System doubles as stopping brake and "parking" brake.
Electrical control of antiferromagnetic metal up to 15 nm
NASA Astrophysics Data System (ADS)
Zhang, PengXiang; Yin, GuFan; Wang, YuYan; Cui, Bin; Pan, Feng; Song, Cheng
2016-08-01
Manipulation of antiferromagnetic (AFM) spins by electrical means is on great demand to develop the AFM spintronics with low power consumption. Here we report a reversible electrical control of antiferromagnetic moments of FeMn up to 15 nm, using an ionic liquid to exert a substantial electric-field effect. The manipulation is demonstrated by the modulation of exchange spring in [Co/Pt]/FeMn system, where AFM moments in FeMn pin the magnetization rotation of Co/Pt. By carrier injection or extraction, the magnetic anisotropy of the top layer in FeMn is modulated to influence the whole exchange spring and then passes its influence to the [Co/Pt]/FeMn interface, through a distance up to the length of exchange spring that fully screens electric field. Comparing FeMn to IrMn, despite the opposite dependence of exchange bias on gate voltages, the same correlation between carrier density and exchange spring stiffness is demonstrated. Besides the fundamental significance of modulating the spin structures in metallic AFM via all-electrical fashion, the present finding would advance the development of low-power-consumption AFM spintronics.
Barros, Lillian; Carvalho, Ana Maria; Ferreira, Isabel C F R
2010-06-01
Malva sylvestris is widely used in Mediterranean and European traditional medicine and ethnoveterinary for the treatment of external and internal inflammation, as well as injuries. Moreover, its use is not only limited to therapeutic purposes; but also the species is locally regarded as a food wild herb. Considering that antioxidants and free radical scavengers can exert also an anti-inflammatory effect, the extracts of different parts of the medicinal/edible plant M. sylvestris (leaves, flowers, immature fruits and leafy flowered stems) were compared for their nutraceutical potential (antioxidant properties) and chemical composition. Particularly, mallow leaves revealed very strong antioxidant properties including radical-scavenging activity (EC(50)=0.43 mg/mL), reducing power (0.07 mg/mL) and lipid peroxidation inhibition in lipossomes (0.04 mg/mL) and brain cells homogenates (0.09 mg/mL). This part of the plant is also the richest in nutraceuticals such as powerful antioxidants (phenols, flavonoids, carotenoids, and tocopherols), unsaturated fatty acids (e.g. alpha-linolenic acid), and minerals measured in ash content. Copyright 2010 Elsevier Ltd. All rights reserved.
Expanding the scope of leadership training in medicine.
Gabel, Stewart
2014-06-01
All physicians take a leadership role at some point in their career-some exert influence in their practices and communities as informal leaders, and others hold formal leadership roles to which they are appointed or elected. These formal leadership roles convey power to those individuals who hold such positions. Formal leadership, however, is limited in its influence unless it is accompanied by a series of personal and interpersonal competencies that characterize both formal and informal leaders.Many physicians who do not hold formal leadership roles will be called on to provide (or will wish to provide) informal leadership at various times in their careers. Both formal and informal leaders should be trained in the personal and interpersonal competencies necessary for effective leadership to advance the principles-driven and values-oriented goals inherent in the health care enterprise.In this article, the author defines leadership and describes the characteristics of formal and informal leaders, then discusses the types of leadership and the power derived from different leadership roles. He concludes by arguing in favor of expanding the scope of leadership training to include informal as well as formal leaders.
Lietzow, Julika; Wohlgemuth, Franziska; Hoefig, Carolin S.; Wiedmer, Petra; Schweizer, Ulrich; Köhrle, Josef; Schürmann, Annette
2015-01-01
Effective and safe antiobesity drugs are still needed in face of the obesity pandemic worldwide. Recent interventions in rodents revealed 3,5-diiodo-L-thyronine (3,5-T2) as a metabolically active iodothyronine affecting energy and lipid metabolism without thyromimetic side effects typically associated with T3 administration. Accordingly, 3,5-T2 has been proposed as a potential hypolipidemic agent for treatment of obesity and hepatic steatosis. In contrast to other observations, our experiments revealed dose-dependent thyromimetic effects of 3,5-T2 akin to those of T3 in diet-induced obese male C57BL/6J mice. 3,5-T2 treatment exerted a negative feedback regulation on the hypothalamus-pituitary-thyroid axis, similar to T3. This is demonstrated by decreased expression of genes responsive to thyroid hormones (TH) in pituitary resulting in a suppressed thyroid function with lower T4 and T3 concentrations in serum and liver of 3,5-T2-treated mice. Analyses of hepatic TH target genes involved in lipid metabolism revealed T3-like changes in gene expression and increased type I-deiodinase activity after application of 3,5-T2 (2.5 μg/g body weight). Reduced hepatic triglyceride and serum cholesterol concentrations reflected enhanced lipid metabolism. Desired increased metabolic rate and reduction of different fat depots were, however, compromised by increased food intake preventing significant body weight loss. Moreover, enlarged heart weights indicate potential cardiac side effects of 3,5-T2 beyond hepatic thyromimetic actions. Altogether, the observed thyromimetic effects of 3,5-T2 in several mouse TH target tissues raise concern about indiscriminate administration of 3,5-T2 as powerful natural hormone for the treatment of hyperlipidemia and pandemic obesity. PMID:25322465
Jonas, Wenke; Lietzow, Julika; Wohlgemuth, Franziska; Hoefig, Carolin S; Wiedmer, Petra; Schweizer, Ulrich; Köhrle, Josef; Schürmann, Annette
2015-01-01
Effective and safe antiobesity drugs are still needed in face of the obesity pandemic worldwide. Recent interventions in rodents revealed 3,5-diiodo-L-thyronine (3,5-T2) as a metabolically active iodothyronine affecting energy and lipid metabolism without thyromimetic side effects typically associated with T3 administration. Accordingly, 3,5-T2 has been proposed as a potential hypolipidemic agent for treatment of obesity and hepatic steatosis. In contrast to other observations, our experiments revealed dose-dependent thyromimetic effects of 3,5-T2 akin to those of T3 in diet-induced obese male C57BL/6J mice. 3,5-T2 treatment exerted a negative feedback regulation on the hypothalamus-pituitary-thyroid axis, similar to T3. This is demonstrated by decreased expression of genes responsive to thyroid hormones (TH) in pituitary resulting in a suppressed thyroid function with lower T4 and T3 concentrations in serum and liver of 3,5-T2-treated mice. Analyses of hepatic TH target genes involved in lipid metabolism revealed T3-like changes in gene expression and increased type I-deiodinase activity after application of 3,5-T2 (2.5 μg/g body weight). Reduced hepatic triglyceride and serum cholesterol concentrations reflected enhanced lipid metabolism. Desired increased metabolic rate and reduction of different fat depots were, however, compromised by increased food intake preventing significant body weight loss. Moreover, enlarged heart weights indicate potential cardiac side effects of 3,5-T2 beyond hepatic thyromimetic actions. Altogether, the observed thyromimetic effects of 3,5-T2 in several mouse TH target tissues raise concern about indiscriminate administration of 3,5-T2 as powerful natural hormone for the treatment of hyperlipidemia and pandemic obesity.
Alvarez, Pedro; Alvarado, Carmen; Mathieu, Florence; Jiménez, Liliana; De la Fuente, Mónica
2006-12-01
Cereals naturally contain a great variety of polyphenols, which exert a wide range of physiological effects both in vitro and in vivo. Many of their protective effects, including an improvement of the function and redox state of immune cells in unhealthy or aged subjects come from their properties as powerful antioxidant compounds. However, whether cereal-based dietary supplementation positively affects the immune function and cellular redox state of healthy subjects remains unclear. To investigate the effects of supplementation (20% wt/wt) for 5 weeks with four different cereal fractions on healthy mice. Several parameters of function and redox state of peritoneal leukocytes were measured. The cereals, named B (wheat germ), C (buckwheat flour), D (fine rice bran) and E (wheat middlings) contained different amounts of gallic acid, p-hydroxybenzoic acid, vanillic acid, sinapic acid, p-coumaric acid, ferulic acid, quercetin, catechin, rutin and oryzanol as major polyphenols. In general, all cereal fractions caused an improvement of the leukocyte parameters studied such as chemotaxis capacity, microbicidal activity, lymphoproliferative response to mitogens, interleukin-2 (IL-2) and tumor necrosis factor (TNFalpha) release, as well as oxidized glutathione (GSSG), GSSG/GSH ratio, catalase (CAT) activity and lipid oxidative damage. We observed similar effects among the cereal fractions. The results suggest that some of these effects may due, at least partially, to the antioxidant activity of the polyphenols naturally present in cereals. Since an appropriate function of the leukocytes has been proposed as marker of the health state, a short-term intake of cereals seems to be sufficient to exert a benefit in the health of the general population. However, further studies are needed to assess the optimal doses and to find out which active polyphenols are able to mediate the observed physiological effects before recommending their regular consumption.
Genetic risk and a primary role for cell-mediated immune mechanisms in multiple sclerosis
Sawcer, Stephen; Hellenthal, Garrett; Pirinen, Matti; Spencer, Chris C.A.; Patsopoulos, Nikolaos A.; Moutsianas, Loukas; Dilthey, Alexander; Su, Zhan; Freeman, Colin; Hunt, Sarah E.; Edkins, Sarah; Gray, Emma; Booth, David R.; Potter, Simon C.; Goris, An; Band, Gavin; Oturai, Annette Bang; Strange, Amy; Saarela, Janna; Bellenguez, Céline; Fontaine, Bertrand; Gillman, Matthew; Hemmer, Bernhard; Gwilliam, Rhian; Zipp, Frauke; Jayakumar, Alagurevathi; Martin, Roland; Leslie, Stephen; Hawkins, Stanley; Giannoulatou, Eleni; D’alfonso, Sandra; Blackburn, Hannah; Boneschi, Filippo Martinelli; Liddle, Jennifer; Harbo, Hanne F.; Perez, Marc L.; Spurkland, Anne; Waller, Matthew J; Mycko, Marcin P.; Ricketts, Michelle; Comabella, Manuel; Hammond, Naomi; Kockum, Ingrid; McCann, Owen T.; Ban, Maria; Whittaker, Pamela; Kemppinen, Anu; Weston, Paul; Hawkins, Clive; Widaa, Sara; Zajicek, John; Dronov, Serge; Robertson, Neil; Bumpstead, Suzannah J.; Barcellos, Lisa F.; Ravindrarajah, Rathi; Abraham, Roby; Alfredsson, Lars; Ardlie, Kristin; Aubin, Cristin; Baker, Amie; Baker, Katharine; Baranzini, Sergio E.; Bergamaschi, Laura; Bergamaschi, Roberto; Bernstein, Allan; Berthele, Achim; Boggild, Mike; Bradfield, Jonathan P.; Brassat, David; Broadley, Simon A.; Buck, Dorothea; Butzkueven, Helmut; Capra, Ruggero; Carroll, William M.; Cavalla, Paola; Celius, Elisabeth G.; Cepok, Sabine; Chiavacci, Rosetta; Clerget-Darpoux, Françoise; Clysters, Katleen; Comi, Giancarlo; Cossburn, Mark; Cournu-Rebeix, Isabelle; Cox, Mathew B.; Cozen, Wendy; Cree, Bruce A.C.; Cross, Anne H.; Cusi, Daniele; Daly, Mark J.; Davis, Emma; de Bakker, Paul I.W.; Debouverie, Marc; D’hooghe, Marie Beatrice; Dixon, Katherine; Dobosi, Rita; Dubois, Bénédicte; Ellinghaus, David; Elovaara, Irina; Esposito, Federica; Fontenille, Claire; Foote, Simon; Franke, Andre; Galimberti, Daniela; Ghezzi, Angelo; Glessner, Joseph; Gomez, Refujia; Gout, Olivier; Graham, Colin; Grant, Struan F.A.; Guerini, Franca Rosa; Hakonarson, Hakon; Hall, Per; Hamsten, Anders; Hartung, Hans-Peter; Heard, Rob N.; Heath, Simon; Hobart, Jeremy; Hoshi, Muna; Infante-Duarte, Carmen; Ingram, Gillian; Ingram, Wendy; Islam, Talat; Jagodic, Maja; Kabesch, Michael; Kermode, Allan G.; Kilpatrick, Trevor J.; Kim, Cecilia; Klopp, Norman; Koivisto, Keijo; Larsson, Malin; Lathrop, Mark; Lechner-Scott, Jeannette S.; Leone, Maurizio A.; Leppä, Virpi; Liljedahl, Ulrika; Bomfim, Izaura Lima; Lincoln, Robin R.; Link, Jenny; Liu, Jianjun; Lorentzen, Åslaug R.; Lupoli, Sara; Macciardi, Fabio; Mack, Thomas; Marriott, Mark; Martinelli, Vittorio; Mason, Deborah; McCauley, Jacob L.; Mentch, Frank; Mero, Inger-Lise; Mihalova, Tania; Montalban, Xavier; Mottershead, John; Myhr, Kjell-Morten; Naldi, Paola; Ollier, William; Page, Alison; Palotie, Aarno; Pelletier, Jean; Piccio, Laura; Pickersgill, Trevor; Piehl, Fredrik; Pobywajlo, Susan; Quach, Hong L.; Ramsay, Patricia P.; Reunanen, Mauri; Reynolds, Richard; Rioux, John D.; Rodegher, Mariaemma; Roesner, Sabine; Rubio, Justin P.; Rückert, Ina-Maria; Salvetti, Marco; Salvi, Erika; Santaniello, Adam; Schaefer, Catherine A.; Schreiber, Stefan; Schulze, Christian; Scott, Rodney J.; Sellebjerg, Finn; Selmaj, Krzysztof W.; Sexton, David; Shen, Ling; Simms-Acuna, Brigid; Skidmore, Sheila; Sleiman, Patrick M.A.; Smestad, Cathrine; Sørensen, Per Soelberg; Søndergaard, Helle Bach; Stankovich, Jim; Strange, Richard C.; Sulonen, Anna-Maija; Sundqvist, Emilie; Syvänen, Ann-Christine; Taddeo, Francesca; Taylor, Bruce; Blackwell, Jenefer M.; Tienari, Pentti; Bramon, Elvira; Tourbah, Ayman; Brown, Matthew A.; Tronczynska, Ewa; Casas, Juan P.; Tubridy, Niall; Corvin, Aiden; Vickery, Jane; Jankowski, Janusz; Villoslada, Pablo; Markus, Hugh S.; Wang, Kai; Mathew, Christopher G.; Wason, James; Palmer, Colin N.A.; Wichmann, H-Erich; Plomin, Robert; Willoughby, Ernest; Rautanen, Anna; Winkelmann, Juliane; Wittig, Michael; Trembath, Richard C.; Yaouanq, Jacqueline; Viswanathan, Ananth C.; Zhang, Haitao; Wood, Nicholas W.; Zuvich, Rebecca; Deloukas, Panos; Langford, Cordelia; Duncanson, Audrey; Oksenberg, Jorge R.; Pericak-Vance, Margaret A.; Haines, Jonathan L.; Olsson, Tomas; Hillert, Jan; Ivinson, Adrian J.; De Jager, Philip L.; Peltonen, Leena; Stewart, Graeme J.; Hafler, David A.; Hauser, Stephen L.; McVean, Gil; Donnelly, Peter; Compston, Alastair
2011-01-01
Multiple sclerosis (OMIM 126200) is a common disease of the central nervous system in which the interplay between inflammatory and neurodegenerative processes typically results in intermittent neurological disturbance followed by progressive accumulation of disability.1 Epidemiological studies have shown that genetic factors are primarily responsible for the substantially increased frequency of the disease seen in the relatives of affected individuals;2,3 and systematic attempts to identify linkage in multiplex families have confirmed that variation within the Major Histocompatibility Complex (MHC) exerts the greatest individual effect on risk.4 Modestly powered Genome-Wide Association Studies (GWAS)5-10 have enabled more than 20 additional risk loci to be identified and have shown that multiple variants exerting modest individual effects play a key role in disease susceptibility.11 Most of the genetic architecture underlying susceptibility to the disease remains to be defined and is anticipated to require the analysis of sample sizes that are beyond the numbers currently available to individual research groups. In a collaborative GWAS involving 9772 cases of European descent collected by 23 research groups working in 15 different countries, we have replicated almost all of the previously suggested associations and identified at least a further 29 novel susceptibility loci. Within the MHC we have refined the identity of the DRB1 risk alleles and confirmed that variation in the HLA-A gene underlies the independent protective effect attributable to the Class I region. Immunologically relevant genes are significantly over-represented amongst those mapping close to the identified loci and particularly implicate T helper cell differentiation in the pathogenesis of multiple sclerosis. PMID:21833088
Kaya, F.; Bicer, B.; Erzeybek, M.S.; Cotuk, H.B.
2012-01-01
In this study we assessed the influence of the three different recovery interventions massage (MSG), electrical muscle stimulation (EMS), and passive rest (PR) on lactate disappearance and muscle recovery after exhausting exercise bouts. Twelve healthy male sport students participated in the study. They attended the laboratory on five test days. After measurement of V.O2max and a baseline Wingate test (WGb), the three recovery interventions were tested in random counterbalanced order. High intensity exercise, which consisted of six exhausting exercise bouts (interspersed with active recovery), was followed by MSG, EMS or PR application (24 minutes); then the final Wingate test (WGf) was performed. Lactate, heart rate, peak and mean power, rating of perceived exertion (RPE), and total quality of recovery (TQR) were recorded. In WGf mean power was significantly higher than in WGb for all three recovery modalities (MSG 6.29%, EMS 5.33%, PR 4.84% increase, p < 0.05), but no significant differences in mean and peak power were observed between the three recovery modes (p > 0.05). The heart rate response and the changes in blood lactate concentration were identical in all three interventions during the entire protocol (p = 0.817, p = 0.493, respectively). RPE and TQR scores were also not different among the three interventions (p > 0.05). These results provide further evidence that MSG and EMS are not more effective than PR in the process of recovery from high intensity exercise. PMID:24868117
Singh, Nagendra Madan; Sathyaprabha, T N; Thirthalli, Jagadisha; Andrade, Chittaranjan
2018-01-01
No electroconvulsive therapy (ECT) study on humans or in animal models has so far examined whether differently composed electrical stimuli exert different cardiac electrophysiological effects at constant electrical dose. The subject is important because cardiac electrophysiological changes may provide indirect information about ECT seizure quality as modulated by stimulus composition. Adult female Wistar rats ( n = 20/group) received fixed, moderately suprathreshold (18 mC) electrical stimuli. This stimulus in each of eight groups was formed by varying pulse amplitude, pulse width, pulse frequency, and stimulus duration. The electrocardiogram was recorded, and time and frequency domain variables were examined in 30 s epochs in preictal (30 s before electroconvulsive shock [ECS]), early postictal (starting 15 s after stimulation), and late postictal (5 h after ECS) periods. Alpha for statistical significance was set at P < 0.01 to adjust for multiple hypothesis testing. Cardiac electrophysiological indices in the eight groups did not differ significantly at baseline. At both early and late postictal time points, almost no analysis yielded statistically significant differences between groups for four time domain variables, including heart rate and standard deviation of R-R intervals, and for six frequency domain variables, including low-frequency power, high-frequency power, and total power. Cardiac electrophysiological measures may not be helpful to identify differences in seizure quality that are driven by differences in the composition of electrical stimuli at constant, moderately suprathreshold electrical dose. The generalization of this conclusion to threshold electrical doses and to human contexts requires a study.
Ways of increasing muscular activity by means of isometric muscular exertion
NASA Technical Reports Server (NTRS)
Kovalik, A. V.
1980-01-01
The effect of isometric muscular exertion on the human body was investigated by having subjects perform basic movements in a sitting position in the conventional manner with additional muscle tension at 50% maximum force and at maximum force. The pulse, arterial pressure, skin temperature, respiratory rate, minute respiratory volume and electrical activity of the muscles involved were all measured. Performance of the exercises with maximum muscular exertion for 20 sec and without movement resulted in the greatest shifts in these indices; in the conventional manner substantial changes did not occur; and with isometric muscular exertion with 50% maximum force with and without movement, optimal functional shifts resulted. The latter is recommended for use in industrial exercises for the prevention of hypodynamia. Ten exercises are suggested.
The Influence of law on Strategy
2016-05-26
Approved for public release; distribution is unlimited The Influence of Law on Strategy A Monograph by Kevin G. Rousseau School of Advanced...2016 4. TITLE AND SUBTITLE The Influence of Law on Strategy 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S...NOTES 14. ABSTRACT Strategists must understand the legal dynamics that are exerting an increasingly powerful influence on the legitimate use of
Marten, Robert
2018-04-26
Since 2000, the eight Millennium Development Goals (MDGs) provided the framework for global development efforts transforming the field now known as global health. The MDGs both reflected and contributed to shaping a normative global health agenda. In the field of global health, the role of the state is largely considered to have diminished; however, this paper reasserts states as actors in the conceptualisation and institutionalisation of the MDGs, and illustrates how states exerted power and engaged in the MDG process. States not only sanctioned the MDGs through their heads of states endorsing the Millennium Declaration, but also acted more subtly behind the scenes supporting, enabling, and/or leveraging other actors, institutions and processes to conceptualise and legitimize the MDGs. Appreciating the MDGs' role in the conceptualisation of global health is particularly relevant as the world transitions to the MDGs' successor, the Sustainable Development Goals (SDGs). The SDGs' influence, impact and importance remains to be seen; however, to understand the future of global health and how actors, particularly states, can engage to shape the field, a deeper sense of the MDGs' legacy and how actors engaged in the past is helpful.
Examining Effects of Physical Exertion on the Dynamic Visual Acuity Test in Collegiate Athletes.
Patterson, Jessie N; Murphy, Anna M; Honaker, Julie A
2017-01-01
Acute symptoms of dizziness and/or imbalance commonly experienced in athletes postconcussion are speculated to arise from dysfunction at multiple levels (i.e., inner ear or central vestibular system) to appropriately integrate afferent sensory information. Disruption along any pathway of the balance system can result in symptoms of dizziness, decreased postural control function (vestibulospinal reflex), and reduced vestibulo-ocular reflex function. This may also lead to decreased gaze stability with movements of the head and may account for symptoms of blurred vision or diplopia reported in almost half of athletes sustaining a concussion. Current concussion position statements include measures of postural control to examine changes to the balance system postconcussion. The Balance Error Scoring System (BESS) is a commonly used low-cost postural control measure for concussion assessment. Although this is a widely used measure for documenting balance function on both immediate (sideline) and recovery monitoring, the BESS has been shown to be affected by physical exertion. Therefore, the BESS may not be the most efficient means of examining functional changes to the balance system immediately after head injury. Dynamic Visual Acuity Test (DVAT) has been found to effectively evaluate and monitor changes to the gaze stability system postinjury. Thus, DVAT may be an additional measure in the concussion assessment battery, as well as an alternative for more immediate sideline assessment to help make objective return-to-play decisions. The aim of the study was to determine the effects of physical exertion on a clinical vestibular assessment, the DVAT, in collegiate athletes, as a first step in defining the role of this measure in the concussion assessment battery. Cross-sectional, repeated-measures design. Twenty-eight healthy collegiate athletes (20 males, 8 females; age = 20.25 ± 1.46 yr, range = 18-25 yr) volunteered to participate in the study. Participants were randomly assigned to complete a 20-min protocol of physical exertion or rest. DVAT was completed pre-exertion or rest (pre-DVAT), immediately following the 20-min protocol (post-DVAT I), and again 10 min after the completion of the 20-min protocol (post-DVAT II). Ratings of perceived exertion (RPE) and heart rate (HR) were monitored throughout testing. Repeated-measures analysis of the variance were used to examine the effects of exertion on DVAT. Additionally, intraclass correlation coefficients were used to examine test reliability. No significant main effect was observed for right and left DVAT logarithm of the minimal angle of resolution loss between groups or across time points (p > 0.05). A significant main effect was observed for RPE and HR for groups and time points (p < 0.001), indicating adequate physical exertion and rest. Fair to good reliability (intraclass correlation coefficient values between 0.4 and 0.74) was observed for both rightward and leftward movements of the head across the three time points. Findings from this study suggest that DVAT is not affected by physical exertion and may provide a more immediate assessment of the balance system that may be of use for the sideline concussion assessment. Future studies will be performed to examine additional factors (e.g., background noise, complex visual backgrounds) that may affect DVAT performance in the sideline environment. American Academy of Audiology
Resveratrol: A potential challenger against gastric cancer
Zulueta, Aida; Caretti, Anna; Signorelli, Paola; Ghidoni, Riccardo
2015-01-01
Gastric cancer (GC) is the fourth most common cancer and the second leading cause of cancer-related mortality in the world. Late diagnosis and classical therapeutic approaches such as surgery, chemotherapy and radiotherapy make this disease a still threatening tumor. Genetic asset, environmental stress, dietary habit and infections caused by Helicobacter pylori (H. pylori) are the major causes concurring to GC initiation. A common mechanism is induction of radicals resulting in gastric mucosal injury. A regular food intake of antioxidant and radical scavenging agents has been proposed to exert protection against tumorigenesis. Resveratrol belongs to the polyphenol flavonoids class of antioxidants produced by a restricted number of plants. Resveratrol exerts bactericidal activity against H. pylori and is a powerful antioxidant, thus acting as a tumor preventive agent. Resveratrol intracellular signaling results in growth arrest and apoptosis, so that it can be directed against tumor progression. Resveratrol therapeutic potential against GC initiation and progression are reviewed here. PMID:26457023
NASA Astrophysics Data System (ADS)
Wang, Ashu; Zeng, Lingyan; Wang, Wen; Calle, Fernando
2018-03-01
Due to the piezoelectricity, the density of 2DEG (NS) formed in the AlGaN/GaN heterostructure can be altered when it is deformed externally, which may be exploited to develop pressure sensors and to enhance the performance of power devices by stress engineering based on the heterostructure. In this paper, a 3D electro-mechanical simulation is presented to study how the induced strains and NS for the AlGaN/GaN wafer under bending exerted uniaxial stress are influenced by the edges caused by processing: the fabrication of the mesa used for isolation, the ohmic contact metal, the gate metal, and the passivation. Results show that the influences are dependent on distance between the edges, depth of the edges, and direction of the exerted uniaxial stress.
Effects of Physical Activity on Mathematical Computation among Young Children.
ERIC Educational Resources Information Center
Gabbard, Carl; Barton, Joel
1979-01-01
When 106 second-grade children were tested for simple computation ability in various conditions of induced physical exertion (no exertion v 20, 30, 40, or 50 minutes of activity), significantly higher scores were observed after the 50-minute treatment, and no significant differences were noted between male and female scores. (Author/RL)
ERIC Educational Resources Information Center
Mazerolle, Stephanie M.; Pagnotta, Kelly D.; Casa, Douglas J.; Armstrong, Lawrence; Maresh, Carl
2011-01-01
Context: Current evidence suggests rectal temperature(T[subscript re] and cold-water immersion (CWI) are the most effective means to diagnose and treat exertional heat stroke (EHS), respectively. Educators, clinicians, and students should be apprised of this evidence to guide their practice. Objective: Investigate what athletic training students…
The effect of personality dimensions on functional outcomes in mood disorders.
Leen, Jessica; Soczynska, Joanna K; Gallaugher, Laura Ashley; Woldeyohannes, Hanna O; Alsuwaidan, Mohammad T; Cha, Danielle S; Dale, Roman M; Muzina, David J; Kennedy, Sidney H; McIntyre, Roger S
2013-07-01
Functional impairment associated with mood disorders may be related to a characteristic "profile" of normative personality dimensions. Individuals (age ≥ 18 years) with MDD (n = 400) or BD (n = 317), as defined by the Diagnostic and Statistical Manual of Mental Disorders, fourth edition, text revision (DSM-IV-TR), were enrolled in the IMDCP. Personality was evaluated with the Neuroticism-Extraversion-Openness Five-Factor Inventory (NEO-FFI), and functionality with the Sheehan Disability Scale and Endicott Work Productivity Scale. Path analysis using linear multiple regressions was performed to identify direct and indirect effects of personality on functional impairment. Lower conscientiousness exerted a significant direct effect on global (p = 0.017) and family life dysfunction in individuals with MDD (p = 0.002), as well as lower work productivity in both MDD (p = 0.020) and BD (p = 0.018). Lower extraversion exerted a significant direct effect on social impairment in individuals with BD (p = 0.017). Higher neuroticism and agreeableness as well as lower extraversion exerted indirect effects on global and social dysfunction in individuals with MDD via their effects on depression severity. In BD, higher neuroticism and openness indirectly affected global dysfunction. Family dysfunction was indirectly affected by higher neuroticism and openness as well as lower extraversion in MDD and BD. The results suggest that discrete personality dimensions may exert direct and indirect effects on functional outcomes in individuals with mood disorders. Personalizing disease management approaches in mood disorders with emphasis on vocational rehabilitation may benefit from measurement and intervention targeting personality.
Bigagli, Elisabetta; Cinci, Lorenzo; D'Ambrosio, Mario; Luceri, Cristina
2017-08-01
Ultraviolet B (UVB) exposure is a risk factor for corneal damage resulting in oxidative stress, inflammation and cell death. The aim of this study was to investigate the potential protective effects of a commercial eye drop (Dacriovis™) containing Matricaria chamomilla and Euphrasia officinalis extracts on human corneal epithelial cells (HCEC-12) against UVB radiation-induced oxidative stress and inflammation as well as the underlying mechanisms. The antioxidant potential of the eye drops was evaluated by measuring the ferric reducing antioxidant power and the total phenolic content by Folin-Ciocalteu reagent. HCEC-12 cells were exposed to UVB radiation and treated with the eye drops at various concentrations. Cell viability, wound healing assay, reactive oxygen species (ROS) levels, protein and lipid oxidative damage and COX-2, IL-1β, iNOS, SOD-2, HO-1 and GSS gene expression, were assessed. Eye drops were able to protect corneal epithelial cells from UVB-induced cell death and ameliorated the wound healing; the eye drops exhibited a strong antioxidant activity, decreasing ROS levels and protein and lipid oxidative damage. Eye drops also exerted anti-inflammatory activities by decreasing COX-2, IL-1β, iNOS expression, counteracted UVB-induced GSS and SOD-2 expression and restored HO-1 expression to control levels. These findings suggest that an eye drop containing Matricaria chamomilla and Euphrasia officinalis extracts exerts positive effects against UVB induced oxidative stress and inflammation and may be useful in protecting corneal epithelial cells from UVB exposure. Copyright © 2017 Elsevier B.V. All rights reserved.
Donath, L; Faude, O; Roth, R; Zahner, L
2014-04-01
Stair-climbing serves as a feasible opportunity to remain physically active within everyday-life. Data on neuromuscular and cardiorespiratory performance after regular stair-climbing in seniors are scarce. Forty-eight seniors were stratified to a one- (taking every step, INT1) or two-step strategy (every second step, INT2) or a control group (CON). Thirty-nine seniors [females: n = 22, males: n = 17; age: 70.5 (SD 5.1) years; BMI: 25.8 (3.1) kg/m(2)] completed the 8-week intervention (three weekly sessions). Before and after the intervention, balance, gait, strength, and submaximal endurance (at different intensities) were assessed. Maximal strength and explosive power did not improve significantly (0.10 < P < 0.78). Resting heart rate was significantly reduced in INT2 (-8/min) compared with INT1 (0/min, P = 0.02) and CON (0/min, P = 0.03). Compared with CON, perceived exertion for all intensities (0.007 < P < 0.03) and submaximal exercise heart rate during moderate uphill walking significantly decreased (-11/min; P < 0.05) in INT2. Step counts for forward beam balancing (4.5 cm width) increased in INT2 (P = 0.007) compared with CON. With more pronounced effects in INT2, stair-climbing significantly improved resting and exercise heart rates, perceived exertion, and dynamic balance performance in healthy seniors and may contribute to better overall fitness, reduced fall risk, and less perceived strain during daily life activities. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
The concomitant effects of phrase length and informational content in sentence comprehension.
Thornton, R; MacDonald, M C; Arnold, J E
2000-03-01
Recent evidence suggests that phrase length plays a crucial role in modification ambiguities. Using a self-paced reading task, we extended these results by examining the additional pragmatic effects that length manipulations may exert. The results demonstrate that length not only modulates modification preferences directly, but that it also necessarily changes the informational content of a sentence, which itself affects modification preferences. Our findings suggest that the same length manipulation affects multiple sources of constraints, both structural and pragmatic, which can each exert differing effects on processing.
The neural dynamics underlying the interpersonal effects of emotional expression on decision making
Chen, Xuhai; Zheng, Tingting; Han, Lingzi; Chang, Yingchao; Luo, Yangmei
2017-01-01
Although numerous studies explore the effects of emotion on decision-making, the existing research has mainly focused on the influence of intrapersonal emotions, leaving the influence of one person’s emotions on another’s decisions underestimated. To specify how interpersonal emotions shape decision-making and delineate the underlying neural dynamics involved, the present study examined brain responses to utilitarian feedback combined with angry or happy faces in competitive and cooperative contexts. Behavioral results showed that participants responded slower following losses than wins when competitors express happiness but responded faster following losses than wins when cooperators express anger. Importantly, angry faces in competitive context reversed the differentiation pattern of feedback-related negativity (FRN) between losses and wins and diminished the difference between losses and wins on both P300 and theta power, but only diminished the difference on FRN between losses and wins in cooperative context. However, when partner displays happiness, losses versus wins elicited larger FRN and theta power in competitive context but smaller P300 in both contexts. These results suggest that interpersonal emotions shape decisions during both automatic motivational salience valuation (FRN) and conscious cognitive appraisal (P300) stages of processing, in which different emotional expressions exert interpersonal influence through different routes. PMID:28425491
Individual neurophysiological profile in external effects investigation
NASA Astrophysics Data System (ADS)
Schastlivtseva, Daria; Tatiana Kotrovskaya, D..
Cortex biopotentials are the significant elements in human psychophysiological individuality. Considered that cortical biopotentials are diverse and individually stable, therefore there is the existence of certain dependence between the basic properties of higher nervous activity and cerebral bioelectric activity. The main purpose of the study was to reveal the individual neurophysiological profile and CNS initial functional state manifestation in human electroencephalogram (EEG) under effect of inert gases (argon, xenon, helium), hypoxia, pressure changes (0.02 and 0.2 MPa). We obtained 5-minute eyes closed background EEG on 19 scalp positions using Ag/AgCl electrodes mounted in an electrode cap. All EEG signals were re-referenced to average earlobes; Fast Furies Transformation analysis was used to calculate the relative power spectrum of delta-, theta-, alpha- and beta frequency band in artifact-free EEG. The study involved 26 healthy men who provided written informed consent, aged 20 to 35 years. Data obtained depend as individual EEG type and initial central nervous functional state as intensity, duration and mix of factors. Pronounced alpha rhythm in the raw EEG correlated with their adaptive capacity under studied factor exposure. Representation change and zonal distribution perversion of EEG alpha rhythm were accompanied by emotional instability, increased anxiety and difficulty adapting subjects. High power factor or combination factor with psychological and emotional or physical exertion minimizes individual EEG pattern.
Effects of plyometric training on soccer players
Wang, Ying-Chun; Zhang, Na
2016-01-01
Plyometric training (PT) is a technique used to increase strength and explosiveness. It consists of physical exercises in which muscles exert maximum force at short intervals to increase dynamic performances. In such a training, muscles undergo a rapid elongation followed by an immediate shortening (stretch-shortening contraction), utilizing the elastic energy stored during the stretching phase. There is consensus on the fact that when used, PT contributes to improvement in vertical jump performance, acceleration, leg strength, muscular power, increase of joint awareness and overall sport-specific skills. Consequently, PT which was primarily used by martial artists, sprinters and high jumpers to improve performances has gained in popularity and has been used by athletes in all types of sports. However, although PT has been shown to increase performance variables in many sports, little scientific information is currently available to determine whether PT actually enhances skill performance in soccer players, considering that soccer is an extremely demanding sport. Soccer players require dynamic muscular performance for fighting at all levels of training status, including rapid movements such as acceleration and deceleration of the body, change of direction, vertical and horizontal jumps, endurance, speed as well as power for kicking and tackling. In this review we discussed the effects of PT on soccer players by considering gender and age categories. PMID:27446242
Potentiation and recovery following low- and high-speed isokinetic contractions in boys.
Chaouachi, Anis; Haddad, Monoem; Castagna, Carlo; Wong, Del P; Kaouech, Fathi; Chamari, Karim; Behm, David G
2011-02-01
The objective of this study was to examine the response and recovery to a single set of maximal, low and high angular velocity isokinetic leg extension-flexion contractions with boys. Sixteen boys (11-14 yrs) performed 10 isokinetic contractions at 60°.s-1 (Isok60) and 300°.s-1 (Isok300). Three contractions at both velocities, blood lactate and ratings of perceived exertion were monitored pretest and at 2, 3, 4, and 5 min of recovery (RI). Participants were tested in a random counterbalanced order for each velocity and recovery period. Only a single contraction velocity (300°.s-1 or 60°.s-1) was tested during recovery at each session to remove confounding influences between the recovery intervals. Recovery results showed no change in quadriceps' power at 300°.s-1, quadriceps' power, work and torque at 60°.s-1 and hamstrings' power and work with 60°.s-1. There was an increase during the 2 min RI in hamstrings' power, work and torque and quadriceps' torque with isokinetic contractions at 300°.s-1 suggesting a potentiating effect. Performance impairments during recovery occurred for the hamstrings torque at 60°.s-1 and quadriceps work with 300°.s-1. In conclusion, 10 repetitions of either low or high velocity isokinetic contractions (Isok60 or Isok300) resulted in full recovery or potentiation of most measures within 2 min in boys. The potentiation effect predominantly occurred following the hamstrings Isok300 which might be attributed to a greater agonist-antagonist torque balance and less metabolic stress associated with the shorter duration higher velocity contractions.
Zhang, Jianglin; Shen, Xiaoge; Wang, Kai; Cao, Xueping; Zhang, Cuiping; Zheng, Huoqing; Hu, Fuliang
2016-10-01
Context Numerous studies have reported that propolis possesses strong antioxidant activities. However, their antioxidant molecular mechanisms are unclear. Objective We utilize ethanol extracts of Chinese propolis (EECP) as a reference to compare ethanol extracts of Eucalyptus propolis (EEEP) with ethanol extracts of Baccharis propolis (EEBGP) based on their antioxidant capacities and underlying molecular mechanisms. Materials and methods HPLC and chemical analysis are utilized to evaluate compositions and antioxidant activities. ROS-eliminating effects of EEBGP (20-75 μg/mL), EEEP (1.25-3.75 μg/mL) and EECP (1.25-5 μg/mL) are also determined by flow cytometry analysis. Moreover, we compared antioxidant capacities by determining their effects on expressions of antioxidant genes in RAW264.7 cells with qRT-PCR, western blot and confocal microscopy analysis. Results EEBGP mainly contains chlorogenic acid (8.98 ± 0.86 mg/g), kaempferide (11.18 ± 8.31 mg/g) and artepillin C (107.70 ± 10.86 mg/g), but EEEP contains 10 compositions, whereas EECP contains 17 compositions. Meantime, although EEEP shows DPPH (IC50 19.55 ± 1.28), ABTS (IC50 20.0 ± 0.31) and reducing power (2.70 ± 0.08 mmol TE/g) better than EEBGP's DPPH (IC50 43.85 ± 0.54), ABTS (IC50 38.2 ± 0.33) and reducing power (1.53 ± 0.05 mmol TE/g), EEBGP exerts much higher ROS inhibition rate (40%) than EEEP (under 20%). Moreover, EEBGP strengthen antioxidant system by activating p38/p-p38 and Erk/p-Erk kinase via accelerating nucleus translocation of Nrf2. EEEP and EECP improve antioxidant gene expression only via Erk/p-Erk kinase-Nrf2 signalling pathway. Discussion and conclusion EEBGP and EEEP exert antioxidant activities via different molecular mechanisms, which may depend on chemical compositions.
Insights into Rapid Modulation of Neuroplasticity by Brain Estrogens
Woolfrey, Kevin M.; Penzes, Peter
2013-01-01
Converging evidence from cellular, electrophysiological, anatomic, and behavioral studies suggests that the remodeling of synapse structure and function is a critical component of cognition. This modulation of neuroplasticity can be achieved through the actions of numerous extracellular signals. Moreover, it is thought that it is the integration of different extracellular signals regulation of neuroplasticity that greatly influences cognitive function. One group of signals that exerts powerful effects on multiple neurologic processes is estrogens. Classically, estrogens have been described to exert their effects over a period of hours to days. However, there is now increasing evidence that estrogens can rapidly influence multiple behaviors, including those that require forebrain neural circuitry. Moreover, these effects are found in both sexes. Critically, it is now emerging that the modulation of cognition by rapid estrogenic signaling is achieved by activation of specific signaling cascades and regulation of synapse structure and function, cumulating in the rewiring of neural circuits. The importance of understanding the rapid effects of estrogens on forebrain function and circuitry is further emphasized as investigations continue to consider the potential of estrogenic-based therapies for neuropathologies. This review focuses on how estrogens can rapidly influence cognition and the emerging mechanisms that underlie these effects. We discuss the potential sources and the biosynthesis of estrogens within the brain and the consequences of rapid estrogenic-signaling on the remodeling of neural circuits. Furthermore, we argue that estrogens act via distinct signaling pathways to modulate synapse structure and function in a manner that may vary with cell type, developmental stage, and sex. Finally, we present a model in which the coordination of rapid estrogenic-signaling and activity-dependent stimuli can result in long-lasting changes in neural circuits, contributing to cognition, with potential relevance for the development of novel estrogenic-based therapies for neurodevelopmental or neurodegenerative disorders. PMID:24076546
Fibroblast growth factor-23: what we know, what we don't know, and what we need to know.
Kovesdy, Csaba P; Quarles, Leigh Darryl
2013-09-01
Traditional risk factors of cardiovascular morbidity and mortality such as hypertension, hypercholesterolemia and obesity are paradoxically associated with better outcomes in dialysis patients, and the few trials of interventions targeting modifiable traditional risk factors have yielded disappointing results in this patient population. Non-traditional risk factors such as inflammation, anemia and abnormalities in bone and mineral metabolism have been proposed as potential explanations for the excess mortality seen in patients with chronic kidney disease (CKD) and end-stage renal disease (ESRD), but without clear understanding of what the most important pathophysiologic mechanisms of these risk factors are, which ones might be ideal treatment targets and which therapeutic interventions may be effective and safe in targeting them. Among the novel risk factors, fibroblast growth factor-23 (FGF23) has recently emerged as one of the most powerful predictors of adverse outcomes in patients with CKD and ESRD. FGF23 is a hormone produced by osteoblasts/osteocytes in bone that acts on the kidney to regulate phosphate and vitamin D metabolism through activation of FGF receptor/α-Klotho co-receptor complexes. It is possible that elevated FGF23 may exert its negative impact through distinct mechanisms of action independent from its role as a regulator of phosphorus homeostasis. Elevated circulating FGF23 concentrations have been associated with left ventricular hypertrophy (LVH), and it has been suggested that FGF23 exerts a direct effect on the myocardium. While it is possible that 'off target' effects of FGF23 present in very high concentrations could induce LVH, this possibility is controversial, since α-klotho is not expressed in the myocardium. Another possibility is that FGF23's effect on the heart is mediated indirectly, via 'on target' activation of other humoral pathways. We will review the physiology and pathophysiology of FGF23, the outcomes associated with elevated FGF23 levels, and describe putative mechanisms of action responsible for its negative effects and potential therapeutic strategies to treat these.
Pereira, Ana; Costa, Aldo M; Izquierdo, Mikel; Silva, António J; Bastos, Estela; Marques, Mário C
2013-10-01
Genetic variation of the human ACE I/D and ACTN3 R577X polymorphisms subsequent to 12 weeks of high-speed power training on maximal strength (1RM) of the arm and leg muscles, muscle power performance (counter-movement jump), and functional capacity (sit-to-stand test) was examined in older Caucasian women [n = 139; mean age 65.5 (8.2) years; 67.0 (10.0) kg and 1.57 (0.06) m]. Chelex 100 was used for DNA extraction, and genotype was determined by PCR-RFLP methods. Muscular strength, power, and functional testing were conducted at baseline (T1) and after 12 weeks (T2) of high-speed power training. At baseline, the ACE I/D and ACTN3 R/X polymorphisms were not associated with muscle function or muscularity phenotypes in older Caucasian women. After the 12-week high-speed training program, subjects significantly increased their muscular and functional capacity performance (p < 0.05). For both polymorphisms, significant genotype-training interaction (p < 0.05) was found in all muscular performance indices, except for 1RM leg extension in the ACE I/D (p = 0.187). Analyses of the combined effects between genotypes showed significant differences in all parameters (p < 0.05) in response to high-speed power training between the power (ACTN3 RR + RX & ACE DD) versus "non-power" muscularity-oriented genotypes (ACTN3 XX & ACE II + ID)]. Our data suggest that the ACE and ACTN3 genotypes (single or combined) exert a significant influence in the muscle phenotypes of older Caucasian women in response to high-speed power training. Thus, the ACE I/D and ACTN3 R/X polymorphisms are likely factors in modulating exercise-related phenotypes in older women, particularly in response to a resistance training stimuli.
Exercise, physical activity, and exertion over the business cycle.
Colman, Gregory; Dave, Dhaval
2013-09-01
Shifts in time and income constraints over economic expansions and contractions would be expected to affect individuals' behaviors. We explore the impact of the business cycle on individuals' exercise, time use, and total physical exertion, utilizing information on 112,000 individual records from the 2003-2010 American Time Use Surveys. In doing so, we test a key causal link that has been hypothesized in the relation between unemployment and health, but not heretofore assessed. Using more precise measures of exercise (and other activities) than previous studies, we find that as work-time decreases during a recession, recreational exercise, TV-watching, sleeping, childcare, and housework increase. This, however, does not compensate for the decrease in work-related exertion due to job-loss, and total physical exertion declines. These effects are strongest among low-educated men, which is validating given that employment in the Great Recession has declined most within manufacturing, mining, and construction. We also find evidence of intra-household spillover effects, wherein individuals respond to shifts in spousal employment conditional on their own labor supply. The decrease in total physical activity during recessions is especially problematic for vulnerable populations concentrated in boom-and-bust industries, and may have longer-term effects on obesity and related health outcomes. Copyright © 2013 Elsevier Ltd. All rights reserved.
Grapple fixture for use with electromagnetic attachment mechanism
NASA Technical Reports Server (NTRS)
Monford, Jr., Leo G. (Inventor)
1995-01-01
An electromagnetic attachment mechanism for use as an end effector of a remote manipulator system. A pair of electromagnets 15A,15B, each with a U-shaped magnetic core with a pull-in coil 34 and two holding coils 35,36 are mounted by a spring suspension system 38,47 on a base plate 25 of the mechanism housing 30 with end pole pieces 21,22 adapted to move through openings in the base plate when the attractive force of the electromagnets is exerted on a strike plate 65 of a grapple fixture 20 affixed to a target object 14. The pole pieces are spaced by an air gap from the strike plate when the mechanism first contacts the grapple fixture. An individual control circuit and power source is provided for the pull-in coil and one holding coil of each electromagnet. A back-up control circuit connected to the two power sources and a third power source is provided for the remaining holding coils. When energized, the pull-in coils overcome the suspension system and air gap and are automatically de-energized when the pole pieces move to grapple and impose a preload force across the grapple interface. A battery back-up 89A,89B is a redundant power source for each electromagnet in each individual control circuit and is automatically connected upon failure of the primary power source. A centerline mounted camera 31 and video monitor 70 are used in cooperation with a target pattern 19 on the reflective surface 67 of the strike plate to effect targeting and alignment.
Fernandes, Magda L; Oliveira, Welser Machado de; Santos, Maria do Carmo Vasconcellos; Gomez, Renato S
2015-01-01
Sedation for electroencephalography in uncooperative patients is a controversial issue because majority of sedatives, hypnotics, and general anesthetics interfere with the brain's electrical activity. Chloral hydrate (CH) is typically used for this sedation, and dexmedetomidine (DEX) was recently tested because preliminary data suggest that this drug does not affect the electroencephalogram (EEG). The aim of the present study was to compare the EEG pattern during DEX or CH sedation to test the hypothesis that both drugs exert similar effects on the EEG. A total of 17 patients underwent 2 EEGs on 2 separate occasions, one with DEX and the other with CH. The EEG qualitative variables included the phases of sleep and the background activity. The EEG quantitative analysis was performed during the first 2 minutes of the second stage of sleep. The EEG quantitative variables included density, duration, and amplitude of the sleep spindles and absolute spectral power. The results showed that the qualitative analysis, density, duration, and amplitude of sleep spindles did not differ between DEX and CH sedation. The power of the slow-frequency bands (δ and θ) was higher with DEX, but the power of the faster-frequency bands (α and β) was higher with CH. The total power was lower with DEX than with CH. The differences of DEX and CH in EEG power did not change the EEG qualitative interpretation, which was similar with the 2 drugs. Other studies comparing natural sleep and sleep induced by these drugs are needed to clarify the clinical relevance of the observed EEG quantitative differences.
An experimental demonstration that early-life competitive disadvantage accelerates telomere loss
Nettle, Daniel; Monaghan, Pat; Gillespie, Robert; Brilot, Ben; Bedford, Thomas; Bateson, Melissa
2015-01-01
Adverse experiences in early life can exert powerful delayed effects on adult survival and health. Telomere attrition is a potentially important mechanism in such effects. One source of early-life adversity is the stress caused by competitive disadvantage. Although previous avian experiments suggest that competitive disadvantage may accelerate telomere attrition, they do not clearly isolate the effects of competitive disadvantage from other sources of variation. Here, we present data from an experiment in European starlings (Sturnus vulgaris) that used cross-fostering to expose siblings to divergent early experience. Birds were assigned either to competitive advantage (being larger than their brood competitors) or competitive disadvantage (being smaller than their brood competitors) between days 3 and 12 post-hatching. Disadvantage did not affect weight gain, but it increased telomere attrition, leading to shorter telomere length in disadvantaged birds by day 12. There were no effects of disadvantage on oxidative damage as measured by plasma lipid peroxidation. We thus found strong evidence that early-life competitive disadvantage can accelerate telomere loss. This could lead to faster age-related deterioration and poorer health in later life. PMID:25411450
An experimental demonstration that early-life competitive disadvantage accelerates telomere loss.
Nettle, Daniel; Monaghan, Pat; Gillespie, Robert; Brilot, Ben; Bedford, Thomas; Bateson, Melissa
2015-01-07
Adverse experiences in early life can exert powerful delayed effects on adult survival and health. Telomere attrition is a potentially important mechanism in such effects. One source of early-life adversity is the stress caused by competitive disadvantage. Although previous avian experiments suggest that competitive disadvantage may accelerate telomere attrition, they do not clearly isolate the effects of competitive disadvantage from other sources of variation. Here, we present data from an experiment in European starlings (Sturnus vulgaris) that used cross-fostering to expose siblings to divergent early experience. Birds were assigned either to competitive advantage (being larger than their brood competitors) or competitive disadvantage (being smaller than their brood competitors) between days 3 and 12 post-hatching. Disadvantage did not affect weight gain, but it increased telomere attrition, leading to shorter telomere length in disadvantaged birds by day 12. There were no effects of disadvantage on oxidative damage as measured by plasma lipid peroxidation. We thus found strong evidence that early-life competitive disadvantage can accelerate telomere loss. This could lead to faster age-related deterioration and poorer health in later life.
Koizumi, Shinji; Ohno, Shotaro; Otsuka, Fuminori
2012-01-01
Gene expression processes are now recognized as important targets of the toxic effects exerted by industrial chemicals. The transient transfection assay is a powerful tool to evaluate such effects. Thus, we developed a versatile assay system by constructing a basic reporter plasmid in which the regulatory DNA sequence to be studied can easily be substituted. To verify the performance of this system, reporter plasmids carrying any of the three distinct regulatory sequences, estrogen responsive element (ERE), glucocorticoid responsive element (GRE) and xenobiotic responsive element (XRE) were constructed. After transfection of human cells, these plasmids successfully expressed the relevant reporter genes in response to specific inducers, β-estradiol, dexamethasone and 3-methylcholanthrene, respectively. Several industrial chemicals were assayed using these reporter plasmids, and the ability of p-dimethylaminoazobenzene to elevate GRE- and XRE-mediated transcription was detected. α-Naphthylamine and o-tolidine were also observed to increase the XRE-mediated response. The transfection assay system established here will be useful to evaluate the effects of a wide variety of industrial chemicals.
Cheng, Ni; Du, Bing; Wang, Yuan; Gao, Hui; Cao, Wei; Zheng, Jianbin; Feng, Fan
2014-05-01
The antioxidant potential of jujube honey, one of the most widely consumed honeys in China, has never been determined fully. In this study, jujube honey from six geographical origins in China was analyzed for individual phenolic acid, total phenolic content, and the antioxidant effect in chronic alcohol-related hepatic disease in mice. The results showed that jujube honey from Linxian of Shanxi province contained higher phenol levels, exhibited DPPH antioxidant activity, ferric ion reducing antioxidant power (FRAP) and protective effects against DNA damage. Treatment with jujube honey (Shanxi Linxian) for 12 weeks significantly inhibited serum lipoprotein oxidation, reduced the impact of alcoholism on aspartate aminotransferase (AST) and alanine aminotransferase (ALT). It also inhibited the generation of 8-hydroxy-2-deoxyguanosine (8-OHdG), lowered the levels of malondialdehyde (MDA) and increased the activity of hepatic glutathione peroxidase (GSH-Px). The study indicates that jujube honey exerts potent antioxidant activity and significant protection in hepatic disorders associated with chronic alcoholism. The protective effect is attributed to its antioxidant mechanisms and inhibition of oxidative degradation of lipids.
Low dose creatine supplementation enhances sprint phase of 400 meters swimming performance.
Anomasiri, Wilai; Sanguanrungsirikul, Sompol; Saichandee, Pisut
2004-09-01
This study demonstrated the effect of low dose creatine supplement (10 g. per day) on the sprinting time in the last 50 meters of 400 meters swimming competition, as well as the effect on exertion. Nineteen swimmers in the experimental group received creatine monohydrate 5 g with orange solution 15 g, twice per day for 7 days and nineteen swimmers in the control group received the same quantity of orange solution. The results showed that the swimmers who received creatine supplement lessened the sprinting time in the last 50 meters of 400 meters swimming competition than the control group. (p<0.05). The results of Wingate test (anaerobic power, anaerobic capacity and fatigue index) compared between pre and post supplementation. There was significant difference at p<0.05 in the control group from training effect whereas there was significant difference at p<0.000 from training effect and creatine supplement in the experiment group. Therefore, the creatine supplement in amateur swimmers in the present study enhanced the physical performance up to the maximum capacity.
The functional genomic studies of curcumin.
Huminiecki, Lukasz; Horbańczuk, Jarosław; Atanasov, Atanas G
2017-10-01
Curcumin is a natural plant-derived compound that has attracted a lot of attention for its anti-cancer activities. Curcumin can slow proliferation of and induce apoptosis in cancer cell lines, but the precise mechanisms of these effects are not fully understood. However, many lines of evidence suggested that curcumin has a potent impact on gene expression profiles; thus, functional genomics should be the key to understanding how curcumin exerts its anti-cancer activities. Here, we review the published functional genomic studies of curcumin focusing on cancer. Typically, a cancer cell line or a grafted tumor were exposed to curcumin and profiled with microarrays, methylation assays, or RNA-seq. Crucially, these studies are in agreement that curcumin has a powerful effect on gene expression. In the majority of the studies, among differentially expressed genes we found genes involved in cell signaling, apoptosis, and the control of cell cycle. Curcumin can also induce specific methylation changes, and is a powerful regulator of the expression of microRNAs which control oncogenesis. We also reflect on how the broader technological progress in transcriptomics has been reflected on the field of curcumin. We conclude by discussing the areas where more functional genomic studies are highly desirable. Integrated OMICS approaches will clearly be the key to understanding curcumin's anticancer and chemopreventive effects. Such strategies may become a template for elucidating the mode of action of other natural products; many natural products have pleiotropic effects that are well suited for a systems-level analysis. Copyright © 2017 Elsevier Ltd. All rights reserved.
Lind, Erik; Welch, Amy S; Ekkekakis, Panteleimon
2009-01-01
Despite the well established physical and psychological benefits derived from leading a physically active life, rates of sedentary behaviour remain high. Dropout and non-compliance are major contributors to the problem of physical inactivity. Perceptions of exertion, affective responses (e.g. displeasure or discomfort), and physiological stress could make the exercise experience aversive, particularly for beginners. Shifting one's attentional focus towards environmental stimuli (dissociation) instead of one's body (association) has been theorized to enhance psychological responses and attenuate physiological stress. Research evidence on the effectiveness of attentional focus strategies, however, has been perplexing, covering the entire gamut of possible outcomes (association and dissociation having been shown to be both effective and ineffective). This article examines the effects of manipulations of attentional focus on exertional and affective responses, as well as on exercise economy and tolerance. The possible roles of the characteristics of the exercise stimulus (intensity, duration) and the exercise participants, methodological issues, and limitations of experimental designs are discussed. In particular, the critical role of exercise intensity is emphasized. Dissociative strategies may be more effective in reducing perceptions of exertion and enhancing affective responses at low to moderate exercise intensities, but their effectiveness may be diminished at higher and near-maximal levels, at which physiological cues dominate. Conversely, associative strategies could enable the exerciser to regulate intensity to avoid injury or overexertion. Thus, depending on intensity, both strategies have a place in the 'toolbox' of the public health or exercise practitioner as methods of enhancing the exercise experience and promoting long-term compliance.
ERIC Educational Resources Information Center
Stanish, Heidi I.; Aucoin, Michael
2007-01-01
In order to gain physical fitness and health, exercise must be performed at a sufficient level of intensity. Exercise intensity can be monitored with rated perceived exertion (RPE) scales to promote safe and effective programming. The usefulness of the Children's OMNI Scale as a subjective measure of intensity for adults with intellectual…
Generation of high power sub millimeter radiation using free electron laser
NASA Astrophysics Data System (ADS)
Panwar, J.; Sharma, S. C.; Malik, P.; Yadav, M.; Sharma, R.
2018-03-01
We have developed an analytical formalism to study the emission of high power radiation lying in the sub millimetre range. A relativistic electron beam (REB) is velocity modulated by the pondermotive force exerted by the laser beams. After passing through the drift space, the beam gets density modulated which further interacts with the strong field wiggler and acquires a transverse velocity that couples with the modulated density of the beam in the presence of ion channel which contribute to the non-linear current density which further leads to the emission of the radiation. The output radiation can be modified by changing the wiggler parameters and the energy of the electron beam. The power of the output radiation is found to increase with the modulation. The obtained radiation can be employed for various applications.
Utilization of rotor kinetic energy storage for hybrid vehicles
Hsu, John S [Oak Ridge, TN
2011-05-03
A power system for a motor vehicle having an internal combustion engine, the power system comprises an electric machine (12) further comprising a first excitation source (47), a permanent magnet rotor (28) and a magnetic coupling rotor (26) spaced from the permanent magnet rotor and at least one second excitation source (43), the magnetic coupling rotor (26) also including a flywheel having an inertial mass to store kinetic energy during an initial acceleration to an operating speed; and wherein the first excitation source is electrically connected to the second excitation source for power cycling such that the flywheel rotor (26) exerts torque on the permanent magnet rotor (28) to assist braking and acceleration of the permanent magnet rotor (28) and consequently, the vehicle. An axial gap machine and a radial gap machine are disclosed and methods of the invention are also disclosed.
Solid-tumor mortality in the vicinity of uranium cycle facilities and nuclear power plants in Spain.
López-Abente, G; Aragonés, N; Pollán, M
2001-01-01
To ascertain solid tumor mortality in towns near Spain's four nuclear power plants and four nuclear fuel facilities from 1975 to 1993, we conducted a mortality study based on 12,245 cancer deaths in 283 towns situated within a 30-km radius of the above installations. As nonexposed areas, we used 275 towns lying within a 50- to 100-km radius of each installation, matched by population size and sociodemographic characteristics (income level, proportion of active population engaged in farming, proportion of unemployed, percentage of illiteracy, and province). Using log-linear models, we examined relative risk for each area and trends in risk with increasing proximity to an installation. The results reveal a pattern of solid-tumor mortality in the vicinity of uranium cycle facilities, basically characterized by excess lung [relative risk (RR) 1.12, 95% confidence interval (CI), 1.02-1.25] and renal cancer mortality (RR 1.37, 95% CI, 1.07-1.76). Besides the effects of natural radiation, these results could well be evincing the influence on public health exerted by the environmental impact of mining. No such well-defined pattern appeared in the vicinity of nuclear power plants. Monitoring of cancer incidence and mortality is recommended in areas surrounding nuclear fuel facilities and nuclear power plants, and more specific studies are called for in areas adjacent to installations that have been fully operational for longer periods. In this regard, it is important to use dosimetric information in all future studies. PMID:11485872
1986-09-01
Latin America, including such powers as Mexico, Brazil , and Venezuala (17:4-6). 4. Foreign Military Sales (FMS) and Foreign Military Construction Sales...coastline where it is characterized by swamps and mangrove thickets. Like its counterpart in Nicaragua, the Honduran Mosquitia and adjoining portion of the... Brazil , Columbia, Argentina, and Chile. Other Central American countries have never been strong enough to exert any real influence, although
Role of Endogenous Microbiota, Probiotics and Their Biological Products in Human Health
Howarth, Gordon S.; Wang, Hanru
2013-01-01
Although gut diseases such as inflammatory bowel disease, mucositis and the alimentary cancers share similar pathogenetic features, further investigation is required into new treatment modalities. An imbalance in the gut microbiota, breached gut integrity, bacterial invasion, increased cell apoptosis to proliferation ratio, inflammation and impaired immunity may all contribute to their pathogenesis. Probiotics are defined as live bacteria, which when administered in sufficient amounts, exert beneficial effects to the gastrointestinal tract. More recently, probiotic-derived factors including proteins and other molecules released from living probiotics, have also been shown to exert beneficial properties. In this review we address the potential for probiotics, with an emphasis on probiotic-derived factors, to reduce the severity of digestive diseases and further discuss the known mechanisms by which probiotics and probiotic-derived factors exert their physiological effects. PMID:23306189
Mohos, Steven C.; Kidd, John G.
1957-01-01
Immune serums prepared in rabbits with antigens made from normal mouse organs and tissues that were presumably devoid of large numbers of lymphocytic cells (notably kidney, liver, brain, whole embryos, and erythrocytes) proved lethal for the cells of several transplanted mouse lymphomas in vitro in the presence of complement; but these immune serums, when given intraperitoneally in large amounts to susceptible mice that had been implanted subcutaneously with lymphoma cells of one or another of several types, failed entirely to inhibit growth of the lymphoma cells in vivo. In contrast, immune serums made with cells procured from transplanted mouse lymphomas as antigens, and those made with cells from normal mouse thymus or lymph nodes, acted even more powerfully upon the several types of lymphoma cells in vitro than did the immune serums prepared with normal mouse organs, and when given intraperitoneally to implanted mice they brought about death of the lymphoma cells in vivo, the effect being to a considerable extent specific and referable to an antibody that reacts with neoplastic and non-neoplastic lymphocytic cells of mice, as absorption experiments disclosed. In comparative tests, furthermore, the anti-lymphoma serums acted more powerfully upon the lymphoma cells in vivo than did such chemotherapeutic agents as amethopterin, azaguanine, ethionine, azaserine, and 6-mercaptopurine, given singly or in various combinations in maximal tolerated amounts, though their effects were not so powerful as those exerted by normal guinea pig serum on lymphoma cells of two types that are susceptible to its action in vivo. The significance of the findings was briefly discussed. PMID:13406182
Effect of thermal state and thermal comfort on cycling performance in the heat.
Schulze, Emiel; Daanen, Hein A M; Levels, Koen; Casadio, Julia R; Plews, Daniel J; Kilding, Andrew E; Siegel, Rodney; Laursen, Paul B
2015-07-01
To determine the effect of thermal state and thermal comfort on cycling performance in the heat. Seven well-trained male triathletes completed 3 performance trials consisting of 60 min cycling at a fixed rating of perceived exertion (14) followed immediately by a 20-km time trial in hot (30°C) and humid (80% relative humidity) conditions. In a randomized order, cyclists either drank ambient-temperature (30°C) fluid ad libitum during exercise (CON), drank ice slurry (-1°C) ad libitum during exercise (ICE), or precooled with iced towels and ice slurry ingestion (15 g/kg) before drinking ice slurry ad libitum during exercise (PC+ICE). Power output, rectal temperature, and ratings of thermal comfort were measured. Overall mean power output was possibly higher in ICE (+1.4%±1.8% [90% confidence limit]; 0.4> smallest worthwhile change [SWC]) and likely higher PC+ICE (+2.5%±1.9%; 1.5>SWC) than in CON; however, no substantial differences were shown between PC+ICE and ICE (unclear). Time-trial performance was likely enhanced in ICE compared with CON (+2.4%±2.7%; 1.4>SWC) and PC+ICE (+2.9%±3.2%; 1.9>SWC). Differences in mean rectal temperature during exercise were unclear between trials. Ratings of thermal comfort were likely and very likely lower during exercise in ICE and PC+ICE, respectively, than in CON. While PC+ICE had a stronger effect on mean power output compared with CON than ICE did, the ICE strategy enhanced late-stage time-trial performance the most. Findings suggest that thermal comfort may be as important as thermal state for maximizing performance in the heat.
NASA Astrophysics Data System (ADS)
Denton, Michael John
The issue of market delineation and power in the wholesale electric energy market is explored using three separate approaches: two of these are analyses of spatial pricing data to explore the functional size of the markets, and the third is a series of experimental tests of the effects of different cost structures and market mechanisms on oligopoly strength in those markets. An equilibrium model of spatial network competition is shown to yield linear relationships between spatial prices. A data set comprising two years of spatial weekly peak and off-peak prices and weather for 6 locations in the Western States Coordinating Council and the Southwest Power Pool is subjected to a pairwise cointegration analysis. The use of dummy variables to account the the flow directions is found to significantly improve model performance. The second analytical technique utilizes the extraction of principal components from a spatial price correlation matrix to identify the extent of natural markets. One year of daily price observations for eleven locations within the WSCC is compiled and eigenvectors are extracted and subjected to oblique rotation, each of which is then interpreted as representing a separate geographic market. The results show that two distinct natural markets, correlated at 84%, account for over 96% of the variation in the spatial prices in the WSSC. Together, the findings support the assertion that the wholesale electricity market in the Western U.S. is large and highly competitive. The experimental analysis utilizes a radial three node network in which suppliers located at the outer nodes sell to buyers located at the central node. The parameterization captures the salient characteristics of the existing bulk power markets, and includes cyclical demand, transmission losses, as well as fixed and avoidable fixed costs for all agents. Treatments varied the number of sellers, the avoidable fixed cost structures, and the trading mechanism. Results indicated that sealed bid markets greatly reduced the ability of sellers to exert market power. Overall the existence of higher avoidable fixed costs tended to ameliorate market power effects.
Integrated Pulse Detonation Propulsion and Magnetohydrodynamic Power
NASA Technical Reports Server (NTRS)
Litchford, Ron J.
2001-01-01
The prospects for realizing an integrated pulse detonation propulsion and magnetohydrodynamic (MHD) power system are examined. First, energy requirements for direct detonation initiation of various fuel-oxygen and fuel-air mixtures are deduced from available experimental data and theoretical models. Second, the pumping power requirements for effective chamber scavenging are examined through the introduction of a scavenging ratio parameter and a scavenging efficiency parameter. A series of laboratory experiments were carried out to investigate the basic engineering performance characteristics of a pulse detonation-driven MHD electric power generator. In these experiments, stoichiometric oxy-acetylene mixtures seeded with a cesium hydroxide/methanol spray were detonated at atmospheric pressure in a 1-m-long tube having an i.d. of 2.54 cm. Experiments with a plasma diagnostic channel attached to the end of the tube confirmed the attainment of detonation conditions (p2/p1 approximately 34 and D approximately 2,400 m/sec) and enabled the direct measurement of current density and electrical conductivity (approximately = 6 S/m) behind the detonation wave front, In a second set of experiments, a 30-cm-long continuous electrode Faraday channel, having a height of 2.54 cm and a width of 2 cm, was attached to the end of the tube using an area transition duct. The Faraday channel was inserted in applied magnetic fields of 0.6 and 0.95 T, and the electrodes were connected to an active loading circuit to characterize power extraction dependence on load impedance while also simulating higher effective magnetic induction. The experiments indicated peak power extraction at a load impedance between 5 and 10 Omega. The measured power density was in reasonable agreement with a simple electrodynamic model incorporating a correction for near-electrode potential losses. The time-resolved thrust characteristics of the system were also measured, and it was found that the NM interaction exerted a negligible influence on system thrust and that the measured I(sub sp) of the system (200 see) exceeded that computed for an equivalent nozzleless rocket (120 see).
Integrated Pulse Detonation Propulsion and Magnetohydrodynamic Power
NASA Technical Reports Server (NTRS)
Litchford, R. J.; Lyles, Garry M. (Technical Monitor)
2001-01-01
The prospects for realizing an integrated pulse detonation propulsion and magnetohydrodynamic (MHD) power system are examined. First, energy requirements for direct detonation initiation of various fuel-oxygen and fuel-air mixtures are deduced from available experimental data and theoretical models. Second, the pumping power requirements for effective chamber scavenging are examined through the introduction of a scavenging ratio parameter and a scavenging efficiency parameter. A series of laboratory experiments were carried out to investigate the basic engineering performance characteristics of a pulse detonation-driven MHD electric power generator. In these experiments, stoichiometric oxy-acetylene mixtures seeded with a cesium hydroxide/methanol spray were detonated at atmospheric pressure in a 1-m-long tube having an i.d. of 2.54 cm. Experiments with a plasma diagnostic channel attached to the end of the tube confirmed the attainment of detonation conditions (p(sub 2)/p(sub 1) approx. 34 and D approx. 2,400 m/sec) and enabled the direct measurement of current density and electrical conductivity (=6 S/m) behind the detonation wave front. In a second set of experiments, a 30-cm-long continuous electrode Faraday channel, having a height of 2.54 cm and a width of 2 cm, was attached to the end of the tube using an area transition duct. The Faraday channel was inserted in applied magnetic fields of 0.6 and 0.95 T. and the electrodes were connected to an active loading circuit to characterize power extraction dependence on load impedance while also simulating higher effective magnetic induction. The experiments indicated peak power extraction at a load impedance between 5 and 10 Ohm. The measured power density was in reasonable agreement with a simple electrodynamic model incorporating a correction for near-electrode potential losses. The time-resolved thrust characteristics of the system were also measured, and it was found that the MHD interaction exerted a negligible influence on system thrust and that the measured I(sub sp) of the system (200 sec) exceeded that computed for an equivalent nozzleless rocket (120 sec).
Pi, KyungBae; Lee, KiBeom
2017-10-01
In the current study, we examined the antioxidant and skin-whitening properties of Prunus mume extract (PME). The ability of PME to scavenge 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals was investigated in vitro. At a concentration of 1000 μg/mL, PME neutralized >45% free radical activity. Cell viability assessment with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay revealed that at concentrations <1500 μg/mL, PME does not exert cytotoxic effects on murine B16 melanoma (B16) cells. Morphological analysis disclosed that melanin production is inhibited in B16 cells treated with 250 nM α-melanocyte-stimulating hormone (α-MSH) and PME. We conclude that fruit extracts of P. mume exert a skin-whitening effect by inhibiting melanin production via regulation of melanogenesis-associated protein expression in melanocytes.
Melatonin potentiates the anticonvulsant action of phenobarbital in neonatal rats.
Forcelli, Patrick A; Soper, Colin; Duckles, Anne; Gale, Karen; Kondratyev, Alexei
2013-12-01
Phenobarbital is the most commonly utilized drug for neonatal seizures. However, questions regarding safety and efficacy of this drug make it particularly compelling to identify adjunct therapies that could boost therapeutic benefit. One potential adjunct therapy is melatonin. Melatonin is used clinically in neonatal and pediatric populations, and moreover, it exerts anticonvulsant actions in adult rats. However, it has not been previously evaluated for anticonvulsant effects in neonatal rats. Here, we tested the hypothesis that melatonin would exert anticonvulsant effects, either alone, or in combination with phenobarbital. Postnatal day (P)7 rats were treated with phenobarbital (0-40mg/kg) and/or melatonin (0-80mg/kg) prior to chemoconvulsant challenge with pentylenetetrazole (100mg/kg). We found that melatonin significantly potentiated the anticonvulsant efficacy of phenobarbital, but did not exert anticonvulsant effects on its own. These data provide additional evidence for the further examination of melatonin as an adjunct therapy in neonatal/pediatric epilepsy. Copyright © 2013 Elsevier B.V. All rights reserved.
Melatonin potentiates the anticonvulsant action of phenobarbital in neonatal rats
Forcelli, Patrick A.; Soper, Colin; Duckles, Anne; Gale, Karen; Kondratyev, Alexei
2013-01-01
Phenobarbital is the most commonly utilized drug for neonatal seizures. However, questions regarding safety and efficacy of this drug make it particularly compelling to identify adjunct therapies that could boost therapeutic benefit. One potential adjunct therapy is melatonin. Melatonin is used clinically in neonatal and pediatric populations, and moreover, it exerts anticonvulsant actions in adult rats. However, it has not been previously evaluated for anticonvulsant effects in neonatal rats. Here, we tested the hypothesis that melatonin would exert anticonvulsant effects, either alone, or in combination with phenobarbital, the most commonly utilized anticonvulsant in neonatal medicine. Postnatal day (P)7 rats were treated with phenobarbital (0–40 mg/kg) and/or melatonin (0–80 mg/kg) prior to chemoconvulsant challenge with pentylenetetrazole (100 mg/kg). We found that melatonin significantly potentiated the anticonvulsant efficacy of phenobarbital, but did not exert anticonvulsant effects on its own. These data provide additional evidence for the further examination of melatonin as an adjunct therapy in neonatal/pediatric epilepsy. PMID:24206906
Interest Group Conflict Over Medicaid Expansion: The Surprising Impact of Public Advocates.
Callaghan, Timothy; Jacobs, Lawrence R
2016-02-01
We examined the potential economic, policy, and political influences on the decisions of the 50 US states to expand Medicaid under the Affordable Care Act. We related a measure of relative state progress toward Medicaid expansion updated to 2015 to each state's economic circumstances, established policy frameworks in states, partisan control of state government, and lobbyists for businesses, medical professionals, unions, and public interest organizations. The 9201 lobbyists working on health care reform in state capitols exerted a strong and significant impact on Medicaid expansion. Controlling for confounding factors (including partisanship and existing policy frameworks), we found that business and professional lobbyists exerted a negative effect on state Medicaid expansion and, unexpectedly, that public interest advocates exerted a positive effect. There are 3.1 million adults who lack coverage because they live in the 20 states that refused to expand Medicaid. Although political party and lobbyists for private interests present significant barriers in these states, legislative lobbying on behalf of the uninsured appears likely to be effective.
New weight factor for Brownian force exerted on micro/nano-particles in air flow
NASA Astrophysics Data System (ADS)
Zhang, Peijie; Lin, Jianzhong; Ku, Xiaoke
2018-05-01
In order to effectively describe the effect of Brownian force exerted on the micro/nano-particles in air flow, a new weight factor, which is defined as the ratio of the characteristic velocity of the Brownian motion to the macroscopic velocity, is proposed and applied to the particle settlement under gravity. Results show that the weight factor can quantitatively evaluate the effect of Brownian force on the particle motion. Moreover, the value of the weight factor can also be used to judge the particle motion pattern and determine whether the Brownian force should be taken into account.
The development of rating of perceived exertion-based tests of physical working capacity.
Mielke, Michelle; Housh, Terry J; Malek, Moh H; Beck, Travis W; Schmidt, Richard J; Johnson, Glen O
2008-01-01
The purpose of the present study was to use ratings of perceived exertion (RPE) from the Borg (6-20) and OMNI-Leg (0-10) scales to determine the Physical Working Capacity at the Borg and OMNI thresholds (PWC(BORG) and PWC(OMNI)). PWC(BORG) and PWC(OMNI) were compared with other fatigue thresholds determined from the measurement of heart rate (the Physical Working Capacity at the Heart Rate Threshold: PWC(HRT)), and oxygen consumption (the Physical Working Capacity at the Oxygen Consumption Threshold, PWC(VO2)), as well as the ventilatory threshold (VT). Fifteen men and women volunteers (mean age +/- SD = 22 +/- 1 years) performed an incremental test to exhaustion on an electronically braked ergometer for the determination of VO2 peak and VT. The subjects also performed 4 randomly ordered workbouts to exhaustion at different power outputs (ranging from 60 to 206W) for the determination of PWC(BORG), PWC(OMNI), PWC(HRT), and PWC(VO2). The results indicated that there were no significant mean differences among the fatigue thresholds: PWC(BORG) (mean +/- SD = 133 +/- 37W; 67 +/- 8% of VO2 peak), PWC(OMNI) (137 +/- 44W; 68 +/- 9% of VO2 peak), PWC(HRT) (135 +/- 36W; 68 +/- 8% of VO2 peak), PWC(VO2) (145 +/- 41W; 72 +/- 7% of VO2 peak) and VT (131 +/- 45W; 66 +/- 8% of VO2 peak). The results of this study indicated that the mathematical model used to estimate PWC(HRT) and PWC(VO2) can be applied to ratings of perceived exertion to determine PWC(BORG) and PWC(OMNI) during cycle ergometry. Salient features of the PWC(BORG) and PWC(OMNI) tests are that they are simple to administer and require the use of only an RPE scale, a stopwatch, and a cycle ergometer. Furthermore, the power outputs at the PWC(BORG) and PWC(OMNI) may be useful to estimate the VT noninvasively and without the need for expired gas analysis.
Vargas-Ramírez, Alba L; Medina-Enríquez, Miriam M; Cordero-Rodríguez, Neira I; Ruiz-Cuello, Tatiana; Aguilar-Faisal, Leopoldo; Trujillo-Ferrara, José G; Alcántara-Farfán, Verónica; Rodríguez-Páez, Lorena
2016-07-01
N-ω-chloroacetyl-L-ornithine (NCAO) is an ornithine decarboxylase (ODC) inhibitor that is known to exert cytotoxic and antiproliferative effects on three neoplastic human cancer cell lines (HeLa, MCF-7, and HepG2). Here, we show that NCAO has antiproliferative activity in 13 cancer cell lines, of diverse tissue origin from human and mice, and in a mouse cancer model in vivo. All cell lines were sensitive to NCAO after 72 h of treatment (the EC50 ranged from 1 to 50.6 µmol/l). The Ca Ski cell line was the most sensitive (EC50=1.18±0.07 µmol/l) and MDA-MB-231 was the least sensitive (EC50=50.6±0.3 µmol/l). This ODC inhibitor showed selectivity for cancer cells, exerting almost no cytotoxic effect on the normal Vero cell line (EC50>1000 µmol/l). NCAO induced apoptosis and inhibited tumor cell migration in vitro. Furthermore, in vivo, this compound (at 50 and 100 mg/kg, daily intraperitoneal injection for 7 days) exerted potent antitumor activity against both solid and ascitic tumors in a mouse model using the myeloma (Ag8) cell line. At these same two doses, the toxicological evaluation showed that NCAO has no obvious systemic toxicity. The current results suggest that the antitumor activity is exerted by apoptosis related not only to a local but also a systemic cytotoxic effect exerted by NCAO on tumor cells. The applications for NCAO as an antitumor agent may be extensive; however, further studies are needed to ascertain the antitumor activity on other types of tumor in vivo and to determine the precise molecular mechanism of its activity.
Tinkering with the tinkerer: pollution versus evolution.
Fox, G A
1995-01-01
Pollutants can act as powerful selective forces by altering genetic variability, its intergenerational transfer, and the size, functional viability, adaptability, and survival of future generations. It is at the level of the cell and the individual that meiosis occurs, that genetic diversity is maintained, and behavior, reproduction, growth, and survival occur and are regulated. It is at this level that evolutionary processes occur and most pollutants exert their toxic effects. Chronic exposure to chemicals contributes to the cumulative stress on individuals and disrupts physiological processes and chemically mediated communication thereby threatening the diversity and long-term survival of sexually reproducing biota. Regional or global effects of pollution on the atmosphere, hydrosphere, and lithosphere have indirectly altered Earth's life-support systems, thereby modifying trace metal balance, reproduction, and incidence of UV-B-induced DNA damage in biota. By altering the competitive ability and survival of species, chemical pollutants potentially threaten evolutionary processes and the biodiversity and function of intercepting ecosystems. PMID:7556031
Radiative Forcing Due to Major Aerosol Emitting Sectors in China and India
NASA Technical Reports Server (NTRS)
Streets, David G.; Shindell, Drew Todd; Lu, Zifeng; Faluvegi, Greg
2013-01-01
Understanding the radiative forcing caused by anthropogenic aerosol sources is essential for making effective emission control decisions to mitigate climate change. We examined the net direct plus indirect radiative forcing caused by carbonaceous aerosol and sulfur emissions in key sectors of China and India using the GISS-E2 chemistry-climate model. Diesel trucks and buses (67 mW/ sq. m) and residential biofuel combustion (52 mW/ sq. m) in India have the largest global mean, annual average forcings due mainly to the direct and indirect effects of BC. Emissions from these two sectors in China have near-zero net global forcings. Coal-fired power plants in both countries exert a negative forcing of about -30 mW/ sq. m from production of sulfate. Aerosol forcings are largest locally, with direct forcings due to residential biofuel combustion of 580 mW/ sq. m over India and 416 mW/ sq. m over China, but they extend as far as North America, Europe, and the Arctic
Ritov, V B; Murzakhmetova, M K
1985-08-01
A Ca2-selective electrode was used to study active transport of Ca2+ by sarcoplasmic reticulum fragments of rabbit skeletal muscle and myocardium homogenates. The specific Ca2+ transport activities (mumol Ca2+/min/mg tissue) are 40 = 60 and 3 = 5 units for fast and slow muscles and the myocardium, respectively. Caffeine (5 mM) exerts a powerful inhibitory influence on Ca2+ transport in skeletal muscle homogenates. For fast muscles, the degree of inhibition exceeds 50%. The rate of Ca2+ transport in the myocardium homogenate increases in the presence of creatine phosphate. The latter produces no effect on Ca2+ transport in skeletal muscle homogenates. The high sensitivity of Ca2 transport to caffeine, a specific blocker of Ca2+ transport to the terminal cisterns of the sarcoplasmic reticulum, suggests that the terminal cisterns, apart from being a reservoir for Ca2+ needed for contraction trigger, may play an essential role in muscle relaxation.
Torregrossa, Mary M; Taylor, Jane R
2016-01-01
Identifying effective pharmacological treatments for addictive disorders has remained an elusive goal. Many different classes of drugs have shown some efficacy in preclinical models, but the number of effective clinical therapeutics has remained stubbornly low. The persistence of drug use and the high frequency of relapse is at least partly attributable to the enduring ability of environmental stimuli associated with drug use to maintain behavioral patterns of drug use and induce craving during abstinence. We propose that stimuli associated with drug use exert such powerful control over behavior through the development of abnormally strong memories, and their ability to initiate subconscious sequences of motor actions (habits) that promote uncontrolled drug use. In this chapter, we will review the evidence suggesting that drugs of abuse strengthen associations with cues in the environment and facilitate habit formation. We will also discuss potential mechanisms for disrupting memories associated with drug use to help improve treatments for addiction. © 2016 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Corona, Giulia; Dipartimento di Biologia Sperimentale, Sez. Patologia Sperimentale, Universita degli Studi di Cagliari, 09042 Monserrato; Deiana, Monica
2007-10-26
We investigated the anti-proliferative effects of an olive oil polyphenolic extract on human colon adenocarcinoma cells. Analysis indicated that the extract contained hydroxytyrosol, tyrosol and the various secoiridoid derivatives, including oleuropein. This extract exerted a strong inhibitory effect on cancer cell proliferation, which was linked to the induction of a G2/M phase cell cycle block. Following treatment with the extract (50 {mu}g/ml) the number of cells in the G2/M phase increased to 51.82 {+-} 2.69% relative to control cells (15.1 {+-} 2.5%). This G2/M block was mediated by the ability of olive oil polyphenols (50 {mu}g/ml) to exert rapid inhibitionmore » of p38 (38.7 {+-} 4.7%) and CREB (28.6 {+-} 5.5%) phosphorylation which led to a downstream reduction in COX-2 expression (56.9 {+-} 9.3%). Our data suggest that olive oil polyphenols may exert chemopreventative effects in the large intestine by interacting with signalling pathways responsible for colorectal cancer development.« less
Policy statement—Climatic heat stress and exercising children and adolescents.
Bergeron, Michael F; Devore, Cynthia; Rice, Stephen G
2011-09-01
Results of new research indicate that, contrary to previous thinking, youth do not have less effective thermoregulatory ability, insufficient cardiovascular capacity, or lower physical exertion tolerance compared with adults during exercise in the heat when adequate hydration is maintained. Accordingly, besides poor hydration status, the primary determinants of reduced performance and exertional heat-illness risk in youth during sports and other physical activities in a hot environment include undue physical exertion, insufficient recovery between repeated exercise bouts or closely scheduled same-day training sessions or rounds of sports competition, and inappropriately wearing clothing, uniforms, and protective equipment that play a role in excessive heat retention. Because these known contributing risk factors are modifiable, exertional heat illness is usually preventable. With appropriate preparation, modifications, and monitoring, most healthy children and adolescents can safely participate in outdoor sports and other physical activities through a wide range of challenging warm to hot climatic conditions.
Miller, Kelly F; Borelli, Jessica L; Margolin, Gayla
2017-10-22
Parental overcontrol (OC), behavior that intrusively or dominantly restricts child autonomy, has been identified as a transdiagnostic risk factor for youth. However, it is as yet unknown whether the association between parental OC and child maladjustment remains even when OC is exerted infrequently or by attuned parents. Rather, the selective use of OC might steer children away from danger. Taking a developmental psychopathology approach, this study focuses on the larger parent-child relationship context, testing whether either the dose at which parents demonstrate OC or the degree to which children perceive their parents as attuned determines whether OC is risky or protective for adolescents' adjustment. Among a community sample of 114 families of children followed from the ages of 12-18, we examine whether OC, behaviorally coded from triadic mother-father-child discussions in middle childhood, is associated with later risky behavior and anxiety symptoms in adolescence. Overcontrol exerted by either mothers or fathers had a curvilinear effect on adolescent risky behaviors, and this effect was moderated by children's perceived attunement. Although OC generally was associated with increased risky behaviors, low doses of OC or OC exerted by highly attuned parents protected against engagement in risky behaviors. No main effect of OC was observed on adolescent anxiety; however, mothers' OC interacted with perceived parental attunement, such that OC exerted by less attuned parents predicted greater anxiety. Results underscore that the effect of parenting behaviors depends on the larger parent-child relationship context. © 2017 Family Process Institute.
Modeling Local Item Dependence Due to Common Test Format with a Multidimensional Rasch Model
ERIC Educational Resources Information Center
Baghaei, Purya; Aryadoust, Vahid
2015-01-01
Research shows that test method can exert a significant impact on test takers' performance and thereby contaminate test scores. We argue that common test method can exert the same effect as common stimuli and violate the conditional independence assumption of item response theory models because, in general, subsets of items which have a shared…
ERIC Educational Resources Information Center
Vera, Jesús; Jiménez, Raimundo; García, José Antonio; Perales, José Cesar; Cárdenas, David
2018-01-01
Purpose: The purposes of this study were to (a) investigate the effect of physical effort (cycling for 60 min at 60 ± 5% of individually computed reserve heart-rate capacity), combined with 2 different levels of cognitive demand (2-back, oddball), on intraocular pressure (IOP) and subjective judgments of perceived exertion (ratings of perceived…
Sanjaya, Kadek Heri; Lee, Soomin; Sriwarno, Andar Bagus; Shimomura, Yoshihito; Katsuura, Tetsuo
2014-06-01
In order to reconcile contradictory results from previous studies on manual pushing, a study was conducted to examine the effect of trunk inclination on muscular activities, centre of pressure (COP) and force exertion during static pushing. Ten subjects pushed at 0 degrees, 15 degrees, 30 degrees, and 45 degrees body inclinations in parallel and staggered feet stances. Wall and ground force plates measured pushing force, wall COP, vertical ground reaction force (GRF) and ground COP. Electromyogram data were recorded at 10 trunk muscle sites. Pushing force was found to increase with body inclination. GRF peaked at 15 degrees and reached its lowest level at the 45 degrees inclination. The lowest wall force plate standard deviation of COP displacement was found at the 30 degrees inclination. The lowest low back muscular activity was found at the 15 degrees and 30 degrees inclinations. Based on force exertion, muscular load, and stability, the 30 degrees body inclination was found to be the best posture for static pushing. This study also showed asymmetry in muscular activity and force exertion which has been received less attention in manual pushing studies. These findings will require further study.
Minireview: Animal studies on the role of 50/60-Hertz magnetic fields in carcinogenesis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Loescher, W.; Mevissen, M.
1994-01-01
A number of epidemiological studies have suggested that exposure to 50/60-Hz magnetic fields (MF) from power lines and electrical equipment may be associated with a modestly increased incidence of various type of cancer. Laboratory studies have indicated that nonionizing radiation has no mutagenic effect, i.e. does not initiate cancer. Thus, if 50/60-Hz MF are truly associated with an increased risk of cancer, then these fields must act as a promoter or co-promoter of cancer in cells that have already been initiated. This paper reviews the evidence produced by animal studies. As shown in this review, the available animal data onmore » 50/60-Hz MF exposures seem to indicate that intermediate MF exposure exerts co-promoting effects in different tumor models, particularly cocarcinogenesis models of breast cancer while chronic (up to life-time) exposure may exert promoting effects on [open quotes]spontaneous[close quotes] development of certain tumors. The tumor promoting or co-promoting effects of 50/60-Hz MF exposure found in several animal studies could relate to actions of MF on gene expression, immune surveillance, and Ca[sup 2+] homeostasis as demonstrated by in vitro experiments in cell cultures. However, the most plausible evidence of an in vivo effect of MF exposure which could be related to tumor promotion is reduction of circulating levels of melatonin, i.e. a hormone which is inhibitory to the growth of a wide range of cancers, particularly breast cancer. Animal studies have shown that 50-Hz MF exposure at fluxes as low as 0.3-1 [mu]Tesla significantly reduces nocturnal melatonin levels in plasma. While decrease of melatonin levels alone could explain tumor promoting or copromoting effects of MF exposure, recent data indicate that MF exposure also impairs the effects of melatonin at the cellular level. The oncostatic effect of melatonin on proliferation of a human breast cancer cell line was antagonized by 60-Hz MF exposure at a flux density of 1 [mu]Tesla.« less
Job, Veronika; Bernecker, Katharina; Miketta, Stefanie; Friese, Malte
2015-10-01
Past research indicates that peoples' implicit theories about the nature of willpower moderate the ego-depletion effect. Only people who believe or were led to believe that willpower is a limited resource (limited-resource theory) showed lower self-control performance after an initial demanding task. As of yet, the underlying processes explaining this moderating effect by theories about willpower remain unknown. Here, we propose that the exertion of self-control activates the goal to preserve and replenish mental resources (rest goal) in people with a limited-resource theory. Five studies tested this hypothesis. In Study 1, individual differences in implicit theories about willpower predicted increased accessibility of a rest goal after self-control exertion. Furthermore, measured (Study 2) and manipulated (Study 3) willpower theories predicted an increased preference for rest-conducive objects. Finally, Studies 4 and 5 provide evidence that theories about willpower predict actual resting behavior: In Study 4, participants who held a limited-resource theory took a longer break following self-control exertion than participants with a nonlimited-resource theory. Longer resting time predicted decreased rest goal accessibility afterward. In Study 5, participants with an induced limited-resource theory sat longer on chairs in an ostensible product-testing task when they had engaged in a task requiring self-control beforehand. This research provides consistent support for a motivational shift toward rest after self-control exertion in people holding a limited-resource theory about willpower. (c) 2015 APA, all rights reserved).
NASA Astrophysics Data System (ADS)
Papanicolaou, Athanasios N.; Abban, Benjamin K. B.; Dermisis, Dimitrios C.; Giannopoulos, Christos P.; Flanagan, Dennis C.; Frankenberger, James R.; Wacha, Kenneth M.
2018-01-01
An improved modeling framework for capturing the effects of space and time-variant resistance to overland flow is developed for intensively managed landscapes. The framework builds on the WEPP model but it removes the limitations of the "equivalent" plane and time-invariant roughness assumption. The enhanced model therefore accounts for spatiotemporal changes in flow resistance along a hillslope due to changes in roughness, in profile curvature, and downslope variability. The model is used to quantify the degree of influence—from individual soil grains to aggregates, "isolated roughness elements," and vegetation—on overland flow characteristics under different storm magnitudes, downslope gradients, and profile curvatures. It was found that the net effects of land use change from vegetation to a bare surface resulted in hydrograph peaks that were up to 133% larger. Changes in hillslope profile curvature instead resulted in peak runoff rate changes that were only up to 16%. The stream power concept is utilized to develop a taxonomy that relates the influence of grains, isolated roughness elements, and vegetation, on overland flow under different storm magnitudes and hillslope gradients. Critical storm magnitudes and hillslope gradients were found beyond which the effects of these landscape attributes on the peak stream power were negligible. The results also highlight weaknesses of the space/time-invariant flow resistance assumption and demonstrate that assumptions on landscape terrain characteristics exert a strong control both on the shape and magnitude of hydrographs, with deviations reaching 65% in the peak runoff when space/time-variant resistance effects are ignored in some cases.
Lee, Hyeon Yong; Ryu, Ga Hee; Choi, Woon Yong; Yang, Woo Seung; Lee, Hyeon Woo; Ma, Choong Je
2018-01-01
Spirulina maxima was used as important nutritional source in the Aztec civilization because it is rich in proteins and vitamins. It contains various antioxidants such as phycocyanin and flavonoids. Based on abundant antioxidants, S. maxima is known to possess anti-inflammatory effect, especially on neuronal cells. S. maxima was extracted in water and contain of phycocyanin was identified by high-performance liquid chromatography. Cell viability test was performed with treatment of S. maxima extract. After, oxidative stress-related mechanisms were evaluated by detecting the accumulation of reactive oxygen species (ROS) and Ca 2+ influx, and decrease of mitochondrial membrane potential (MMP) level. Then, the glutathione (GSH) related assays were conducted. The water extracted S. maxima exerted the neuroprotective activity by attenuating the ROS and Ca 2+ formation, maintaining the MMP level, and protecting the activity of the antioxidant enzymes by increasing reduced GSH against oxidative stress compared to control. The results suggested that water extracted S. maxima showed powerful neuroprotective effect through the mechanism related to antioxidant activity, able to preventing the radical-mediated cell death. Water extracted Spirulina maxima contains C-phycocyaninWater extracted Spirulina maxima exerts neuroprotective effect on HT22 cellTo investigate the protective mechanisms, reactive oxygen species, Ca 2+ , mitochondrial membrane potential, Glutathione-related assays were performed. Abbreviations used: ROS: Reactive oxygen species; MMP: Mitochondrial membrane potential; GSH: Glutathione; GSSG: Glutathione disulfide, oxidized glutathione; GPx: Glutathione peroxidase; GR: Glutathione reductase; DMEM: Dulbecco's modified Eagle's medium; FBS: Fetal bovine serum; DCF-DA: 2',7'-dichlorofluorescein diacetate; PBS: Phosphate buffered serum; Rho 123: Rhodamine 123; NADPH: Nicotinamide adenine dinucleotide phosphate; DTNB: 5,5'-dithiobis-2-nitrobenzoic acid, Ellman's reagent; GSSG-R: Glutathione disulfide reductase; MTT: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide; DMSO: Dimethyl sulfoxide; HPLC: High-performance liquid chromatography.
Lee, Hyeon Yong; Ryu, Ga Hee; Choi, Woon Yong; Yang, Woo Seung; Lee, Hyeon Woo; Ma, Choong Je
2018-01-01
Introduction: Spirulina maxima was used as important nutritional source in the Aztec civilization because it is rich in proteins and vitamins. It contains various antioxidants such as phycocyanin and flavonoids. Based on abundant antioxidants, S. maxima is known to possess anti-inflammatory effect, especially on neuronal cells. Materials and Methods: S. maxima was extracted in water and contain of phycocyanin was identified by high-performance liquid chromatography. Cell viability test was performed with treatment of S. maxima extract. After, oxidative stress-related mechanisms were evaluated by detecting the accumulation of reactive oxygen species (ROS) and Ca2+ influx, and decrease of mitochondrial membrane potential (MMP) level. Then, the glutathione (GSH) related assays were conducted. Results: The water extracted S. maxima exerted the neuroprotective activity by attenuating the ROS and Ca2+ formation, maintaining the MMP level, and protecting the activity of the antioxidant enzymes by increasing reduced GSH against oxidative stress compared to control. Conclusion: The results suggested that water extracted S. maxima showed powerful neuroprotective effect through the mechanism related to antioxidant activity, able to preventing the radical-mediated cell death. SUMMARY Water extracted Spirulina maxima contains C-phycocyaninWater extracted Spirulina maxima exerts neuroprotective effect on HT22 cellTo investigate the protective mechanisms, reactive oxygen species, Ca2+, mitochondrial membrane potential, Glutathione-related assays were performed. Abbreviations used: ROS: Reactive oxygen species; MMP: Mitochondrial membrane potential; GSH: Glutathione; GSSG: Glutathione disulfide, oxidized glutathione; GPx: Glutathione peroxidase; GR: Glutathione reductase; DMEM: Dulbecco's modified Eagle's medium; FBS: Fetal bovine serum; DCF-DA: 2',7'-dichlorofluorescein diacetate; PBS: Phosphate buffered serum; Rho 123: Rhodamine 123; NADPH: Nicotinamide adenine dinucleotide phosphate; DTNB: 5,5'-dithiobis-2-nitrobenzoic acid, Ellman's reagent; GSSG-R: Glutathione disulfide reductase; MTT: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide; DMSO: Dimethyl sulfoxide; HPLC: High-performance liquid chromatography. PMID:29720839
NASA Astrophysics Data System (ADS)
Kirchner-Bossi, Nicolas; Porté-Agel, Fernando
2017-04-01
Wind turbine wakes can significantly disrupt the performance of further downstream turbines in a wind farm, thus seriously limiting the overall wind farm power output. Such effect makes the layout design of a wind farm to play a crucial role on the whole performance of the project. An accurate definition of the wake interactions added to a computationally compromised layout optimization strategy can result in an efficient resource when addressing the problem. This work presents a novel soft-computing approach to optimize the wind farm layout by minimizing the overall wake effects that the installed turbines exert on one another. An evolutionary algorithm with an elitist sub-optimization crossover routine and an unconstrained (continuous) turbine positioning set up is developed and tested over an 80-turbine offshore wind farm over the North Sea off Denmark (Horns Rev I). Within every generation of the evolution, the wind power output (cost function) is computed through a recently developed and validated analytical wake model with a Gaussian profile velocity deficit [1], which has shown to outperform the traditionally employed wake models through different LES simulations and wind tunnel experiments. Two schemes with slightly different perimeter constraint conditions (full or partial) are tested. Results show, compared to the baseline, gridded layout, a wind power output increase between 5.5% and 7.7%. In addition, it is observed that the electric cable length at the facilities is reduced by up to 21%. [1] Bastankhah, Majid, and Fernando Porté-Agel. "A new analytical model for wind-turbine wakes." Renewable Energy 70 (2014): 116-123.
Singh, Nagendra Madan; Sathyaprabha, T. N.; Thirthalli, Jagadisha; Andrade, Chittaranjan
2018-01-01
Background: No electroconvulsive therapy (ECT) study on humans or in animal models has so far examined whether differently composed electrical stimuli exert different cardiac electrophysiological effects at constant electrical dose. The subject is important because cardiac electrophysiological changes may provide indirect information about ECT seizure quality as modulated by stimulus composition. Materials and Methods: Adult female Wistar rats (n = 20/group) received fixed, moderately suprathreshold (18 mC) electrical stimuli. This stimulus in each of eight groups was formed by varying pulse amplitude, pulse width, pulse frequency, and stimulus duration. The electrocardiogram was recorded, and time and frequency domain variables were examined in 30 s epochs in preictal (30 s before electroconvulsive shock [ECS]), early postictal (starting 15 s after stimulation), and late postictal (5 h after ECS) periods. Alpha for statistical significance was set at P < 0.01 to adjust for multiple hypothesis testing. Results: Cardiac electrophysiological indices in the eight groups did not differ significantly at baseline. At both early and late postictal time points, almost no analysis yielded statistically significant differences between groups for four time domain variables, including heart rate and standard deviation of R-R intervals, and for six frequency domain variables, including low-frequency power, high-frequency power, and total power. Conclusions: Cardiac electrophysiological measures may not be helpful to identify differences in seizure quality that are driven by differences in the composition of electrical stimuli at constant, moderately suprathreshold electrical dose. The generalization of this conclusion to threshold electrical doses and to human contexts requires a study. PMID:29736058
Rotary-Atomizer Electric Power Generator
NASA Astrophysics Data System (ADS)
Nguyen, Trieu; Tran, Tuan; de Boer, Hans; van den Berg, Albert; Eijkel, Jan C. T.
2015-03-01
We report experimental and theoretical results on a ballistic energy-conversion method based on a rotary atomizer working with a droplet acceleration-deceleration cycle. In a rotary atomizer, liquid is fed onto the center of a rotating flat surface, where it spreads out under the action of the centrifugal force and creates "atomized" droplets at its edge. The advantage of using a rotary atomizer is that the centrifugal force exerted on the fluid on a smooth, large surface is not only a robust form of acceleration, as it avoids clogging, but also easily allows high throughput, and produces high electrical power. We successfully demonstrate an output power of 4.9 mW and a high voltage up to 3120 V. At present, the efficiency of the system is still low (0.14%). However, the conversion mechanism of the system is fully interpreted in this paper, permitting a conceptual understanding of system operation and providing a roadmap for system optimization. This observation will open up a road for building power-generation systems in the near future.
Staab, Katie Lynn; Holzman, Roi; Hernandez, L Patricia; Wainwright, Peter C
2012-05-01
A protrusible upper jaw has independently evolved multiple times within teleosts and has been implicated in the success of two groups in particular: Acanthomorpha and Cypriniformes. We use digital particle image velocimetry (DPIV) to compare suction feeding flow dynamics in a representative of each of these clades: goldfish and bluegill. Using DPIV, we contrast the spatial pattern of flow, the temporal relationship between flow and head kinematics, and the contribution of jaw protrusion to the forces exerted on prey. As expected, the spatial patterns of flow were similar in the two species. However, goldfish were slower to reach maximal kinematic excursions, and were more flexible in the relative timing of jaw protrusion, other jaw movements and suction flows. Goldfish were also able to sustain flow speeds for a prolonged period of time as compared with bluegill, in part because goldfish generate lower peak flow speeds. In both species, jaw protrusion increased the force exerted on the prey. However, slower jaw protrusion in goldfish resulted in less augmentation of suction forces. This difference in force exerted on prey corresponds with differences in trophic niches and feeding behavior of the two species. The bluegill uses powerful suction to capture insect larvae whereas the goldfish uses winnowing to sort through detritus and sediment. The kinethmoid of goldfish may permit jaw protrusion that is independent of lower jaw movement, which could explain the ability of goldfish to decouple suction flows (due to buccal expansion) from upper jaw protrusion. Nevertheless, our results show that jaw protrusion allows both species to augment the force exerted on prey, suggesting that this is a fundamental benefit of jaw protrusion to suction feeders.
Rogerson, Mike; Barton, Jo
2015-01-01
Green exercise research often reports psychological health outcomes without rigorously controlling exercise. This study examines effects of visual exercise environments on directed attention, perceived exertion and time to exhaustion, whilst measuring and controlling the exercise component. Participants completed three experimental conditions in a randomized counterbalanced order. Conditions varied by video content viewed (nature; built; control) during two consistently-ordered exercise bouts (Exercise 1: 60% VO2peakInt for 15-mins; Exercise 2: 85% VO2peakInt to voluntary exhaustion). In each condition, participants completed modified Backwards Digit Span tests (a measure of directed attention) pre- and post-Exercise 1. Energy expenditure, respiratory exchange ratio and perceived exertion were measured during both exercise bouts. Time to exhaustion in Exercise 2 was also recorded. There was a significant time by condition interaction for Backwards Digit Span scores (F2,22 = 6.267, p = 0.007). Scores significantly improved in the nature condition (p < 0.001) but did not in the built or control conditions. There were no significant differences between conditions for either perceived exertion or physiological measures during either Exercise 1 or Exercise 2, or for time to exhaustion in Exercise 2. This was the first study to demonstrate effects of controlled exercise conducted in different visual environments on post-exercise directed attention. Via psychological mechanisms alone, visual nature facilitates attention restoration during moderate-intensity exercise. PMID:26133125
Rogerson, Mike; Barton, Jo
2015-06-30
Green exercise research often reports psychological health outcomes without rigorously controlling exercise. This study examines effects of visual exercise environments on directed attention, perceived exertion and time to exhaustion, whilst measuring and controlling the exercise component. Participants completed three experimental conditions in a randomized counterbalanced order. Conditions varied by video content viewed (nature; built; control) during two consistently-ordered exercise bouts (Exercise 1: 60% VO2peakInt for 15-mins; Exercise 2: 85% VO2peakInt to voluntary exhaustion). In each condition, participants completed modified Backwards Digit Span tests (a measure of directed attention) pre- and post-Exercise 1. Energy expenditure, respiratory exchange ratio and perceived exertion were measured during both exercise bouts. Time to exhaustion in Exercise 2 was also recorded. There was a significant time by condition interaction for Backwards Digit Span scores (F2,22 = 6.267, p = 0.007). Scores significantly improved in the nature condition (p < 0.001) but did not in the built or control conditions. There were no significant differences between conditions for either perceived exertion or physiological measures during either Exercise 1 or Exercise 2, or for time to exhaustion in Exercise 2. This was the first study to demonstrate effects of controlled exercise conducted in different visual environments on post-exercise directed attention. Via psychological mechanisms alone, visual nature facilitates attention restoration during moderate-intensity exercise.
Ismail Suhaimy, Noor Wahida; Noor Azmi, Ahmad Khusairi; Mohtarrudin, Norhafizah; Cheema, Manraj Singh
2017-01-01
Recent study has demonstrated the gastroprotective activity of crude methanolic extract of M. malabathricum leaves. The present study evaluated the gastroprotective potential of semipurified extracts (partitions): petroleum ether, ethyl acetate (EAMM), and aqueous obtained from the methanolic extract followed by the elucidation of the gastroprotective mechanisms of the most effective partition. Using the ethanol-induced gastric ulcer assay, all partitions exerted significant gastroprotection, with EAMM being the most effective partition. EAMM significantly (i) reduced the volume and acidity (free and total) while increasing the pH of gastric juice and enhanced the gastric wall mucus secretion when assessed using the pylorus ligation assay, (ii) increased the enzymatic and nonenzymatic antioxidant activity of the stomach tissue, (iii) lost its gastroprotective activity following pretreatment with N-omega-nitro-L-arginine methyl ester (L-NAME; NO blocker) or carbenoxolone (CBXN; NP-SH blocker), (iv) exerted antioxidant activity against various in vitro oxidation assays, and (v) showed moderate in vitro anti-inflammatory activity via the LOX-modulated pathway. In conclusion, EAMM exerts a remarkable NO/NP-SH-dependent gastroprotective effect that is attributed to its antisecretory and antioxidant activities, ability to stimulate the gastric mucus production and endogenous antioxidant system, and synergistic action of several gastroprotective-induced flavonoids. PMID:28168011
Ergonomics and patient handling.
McCoskey, Kelsey L
2007-11-01
This study aimed to describe patient-handling demands in inpatient units during a 24-hour period at a military health care facility. A 1-day total population survey described the diverse nature and impact of patient-handling tasks relative to a variety of nursing care units, patient characteristics, and transfer equipment. Productivity baselines were established based on patient dependency, physical exertion, type of transfer, and time spent performing the transfer. Descriptions of the physiological effect of transfers on staff based on patient, transfer, and staff characteristics were developed. Nursing staff response to surveys demonstrated how patient-handling demands are impacted by the staff's physical exertion and level of patient dependency. The findings of this study describe the types of transfers occurring in these inpatient units and the physical exertion and time requirements for these transfers. This description may guide selection of the most appropriate and cost-effective patient-handling equipment required for specific units and patients.
Guimarães Drummond E Silva, Fernanda; Miralles, Beatriz; Hernández-Ledesma, Blanca; Amigo, Lourdes; Iglesias, Amadeu Hoshi; Reyes Reyes, Felix Guillermo; Netto, Flavia Maria
2017-02-01
The impact of the naturally present phenolic compounds and/or proteins on the antioxidant capacity of flaxseed products (phenolic fraction, protein concentrates, and hydrolysates) before and after simulated gastrointestinal digestion was studied. For that, whole and phenolic reduced products were assessed. Four glycosylated phenolic compounds (secoisolariciresinol and ferulic, p-coumaric, and caffeic acids) were identified in flaxseed products. Phenolic fraction exerts the highest antioxidant capacity that increased by alkaline hydrolysis and by simulated gastrointestinal digestion. The action of Alcalase and digestive enzymes resulted in an increase of the antioxidant capacity of whole and phenolic reduced products. Principal component analysis showed that proteinaceous samples act as antioxidant is by H + transfer, while those samples containing phenolic compounds exert their effects by both electron donation and H + transfer mechanisms. Protein/peptide-phenolic complexation, confirmed by fluorescence spectra, exerted a positive effect on the antioxidant capacity, mainly in protein concentrates.
Beneficial effect of prolonged heme oxygenase 1 activation in a rat model of chronic heart failure.
Collino, Massimo; Pini, Alessandro; Mugelli, Niccolò; Mastroianni, Rosanna; Bani, Daniele; Fantozzi, Roberto; Papucci, Laura; Fazi, Marilena; Masini, Emanuela
2013-07-01
We and others have previously demonstrated that heme oxygenase 1 (HO-1) induction by acute hemin administration exerts cardioprotective effects. Here, we developed a rat model of heart failure to investigate whether a long-term induction of HO-1 by chronic hemin administration exerted protective effects. Sprague Dawley rats that underwent permanent ligation of the left coronary artery were closely monitored for survival rate analysis and sacrificed on day 28 post-operation. Administration of hemin (4 mg/kg body weight) every other day for 4 weeks induced a massive increase in HO-1 expression and activity, as shown by the increased levels of the two main metabolic products of heme degradation, bilirubin and carbon monoxide (CO). These effects were associated with significant improvement in survival and reduced the extension of myocardial damage. The ischemic hearts of the hemin-treated animals displayed reduced oxidative stress and apoptosis in comparison with the non-treated rats, as shown by the decreased levels of lipid peroxidation, free-radical-induced DNA damage, caspase-3 activity and Bax expression. Besides, chronic HO-1 activation suppressed the elevated levels of myeloperoxidase (MPO) activity, interleukin 1β (IL-1β) production and tumor necrosis factor-α (TNFα) production that were evoked by the ischemic injury, and increased the plasma level of the anti-inflammatory cytokine IL-10. Interestingly, HO-1 inhibitor zinc protoporphyrin IX (ZnPP-IX; 1 mg/kg) lowered bilirubin and CO concentrations to control values, thus abolishing all the cardioprotective effects of hemin. In conclusion, the results demonstrate that chronic HO-1 activation by prolonged administration of hemin improves survival and exerts protective effects in a rat model of myocardial ischemia by exerting a potent antioxidant activity and disrupting multiple levels of the apoptotic and inflammatory cascade.
Takasu, Kumiko; Sakai, Atsushi; Hanawa, Hideki; Shimada, Takashi; Suzuki, Hidenori
2011-11-01
Glial cell line-derived neurotrophic factor (GDNF), a survival-promoting factor for a subset of nociceptive small-diameter neurons, has been shown to exert analgesic effects on neuropathic pain. However, its detailed mechanisms of action are still unknown. In the present study, we investigated the site-specific analgesic effects of GDNF in the neuropathic pain state using lentiviral vector-mediated GDNF overexpression in mice with left fifth lumbar (L5) spinal nerve ligation (SNL) as a neuropathic pain model. A lentiviral vector expressing both GDNF and enhanced green fluorescent protein (EGFP) was constructed and injected into the left dorsal spinal cord, uninjured fourth lumbar (L4) dorsal root ganglion (DRG), injured L5 DRG, or plantar skin of mice. In SNL mice, injection of the GDNF-EGFP-expressing lentivirus into the dorsal spinal cord or uninjured L4 DRG partially but significantly reduced the mechanical allodynia in association with an increase in GDNF protein expression in each virus injection site, whereas injection into the injured L5 DRG or plantar skin had no effects. These results suggest that GDNF exerts its analgesic effects in the neuropathic pain state by acting on the central terminals of uninjured DRG neurons and/or on the spinal cells targeted by the uninjured DRG neurons. This article shows that GDNF exerts its analgesic effects on neuropathic pain by acting on the central terminals of uninjured DRG neurons and/or on the spinal cells targeted by these neurons. Therefore, research focusing on these GDNF-dependent neurons in the uninjured DRG would provide a new strategy for treating neuropathic pain. Copyright © 2011 American Pain Society. Published by Elsevier Inc. All rights reserved.
Influence of warm-up duration and recovery interval prior to exercise on anaerobic performance.
Frikha, M; Chaâri, N; Mezghanni, N; Souissi, N
2016-12-01
The purpose of the study was to determine the impact of different active warm-up (AWU) durations and the rest interval separating it from exercise on anaerobic performance. Eleven male physical education students (22.6 ± 2.52 years; 179.2 ± 4.3 cm; 82.5 ± 9.7 kg; mean ± SD) participated in a cross-over randomized study, and they all underwent the Wingate test after three AWU durations: 5 min (AWU5), 15 min (AWU15) and 20 min (AWU20), with recovery (WREC) or without a recovery interval (NREC) separating the AWU and anaerobic exercise performance. All the AWUs consisted of pedalling at a constant pace of 60 rpm at 50% of the maximal aerobic power. The rest interval between the end of warm-up and the beginning of exercise was set at 5 min. During the Wingate test, peak power (PP), mean power (MP) and the fatigue index (FI) were recorded and analysed. Oral temperature was recorded at rest and at the end of the warm-up. Likewise, rest, post-warm-up and post-Wingate heart rate (HR) and rating of perceived exertion (RPE) were recorded during each session. The ANOVA showed a significant effect of recovery interval, warm-up duration and measurement point on RPE scores (P<0.001). Although the effect of AWU duration on MP and PP was significant (P<0.05), the effect of the recovery interval on both parameters was not significant (P>0.05). Moreover, the analyses showed a significant interaction between recovery interval and AWU duration (P<0.001 and P<0.05 for MP and PP respectively). The AWU15 duration improves the MP and PP when associated with a recovery interval prior to exercise of 5 min. However, the AWU5 duration allows better improvement of power output when the exercise is applied immediately after the warm-up. Consequently, physically active males, as well as educators and researchers interested in anaerobic exercise, must take into account the duration of warm-up and the following recovery interval when practising or assessing activities requiring powerful lower limb muscle contractions.
Chapellier, R.A.
1960-05-24
BS>A drive mechanism was invented for the control rod of a nuclear reactor. Power is provided by an electric motor and an outside source of fluid pressure is utilized in conjunction with the fluid pressure within the reactor to balance the loadings on the motor. The force exerted on the drive mechanism in the direction of scramming the rod is derived from the reactor fluid pressure so that failure of the outside pressure source will cause prompt scramming of the rod.
Leigh, Annballaw Bridget; Cheung, Ho Pan; Lin, Li-Zhu; Ng, Tzi Bun; Lao, Lixing; Zhang, Yanbo; Zhang, Zhang-Jin; Tong, Yao; Sze, Stephen Cho Wing
2017-09-01
The Chinese medicine formula Tian Xian Liquid (TXL) has been used clinically for cancer therapy in China for more than 25 years. However, the comprehensive and holistic effects of its bioactive fractions for various antitumor therapeutic effects have not been unraveled. This is the first study to scientifically elucidate the holistic effect of Chinese medicine formula for treating colon cancer, hence allowing a better understanding of the essence of Chinese medicine formula, through the comparison of the actions of TXL and its functional constituent fractions, including ethyl acetate (EA), butanol (BU), and aqueous (WA) fractions. Tissue-specific proliferative/antiproliferative effects of these fractions on human colorectal carcinoma HT-29 cells and splenocytes were studied by using the MTT assay. Their modulations on the expression of markers of antiproliferation, antimetastasis, reversion of multidrug resistance in treated HT-29 cells were examined with real-time polymerase chain reaction and Western blot analysis, and their modulations in a xenografted nude mouse model were examined by Western blot analysis. Results revealed that EA fraction slightly inhibited the proliferation of HT-29 cells, but tissue-specifically exerted the most potent antiproliferative effect on splenocytes. On the contrary, only TXL and BU fraction tissue-specifically contributed to the proliferation of splenocytes, but inhibited the proliferation of HT-29 cells. WA fraction exerted the most potent antiproliferative effect on HT-29 cells and also the strongest inhibitory action on tumor size in the nude mouse model in our previous study. In the HT-29 model, TXL and WA fraction exerted the most pronounced effect on upregulation of p21 mRNA and protein; TXL, and EA and WA fractions exerted the effect on downregulation of G1 phase cell cycle protein, cyclin D1 mRNA and protein; EA and BU fractions exerted the most prominent anti-invasive effect on anti-invasion via downregulation of MMP-1 mRNA; TXL potently reversed most multidrug resistance via downregulation of MDR-1 protein. In conclusion, the comprehensive and holistic effects of TXL were demonstrated with ( a) mutual accentuation and mutual enhancement, ( b) mutual counteraction and mutual suppression, and ( c) mutual antagonism among the 3 constituent fractions. Moreover, the design of the present study may lead to further development of more tissue-specific effective drugs with minimal side effects for clinical use in combating carcinoma.
The effects of vinblastine on endothelial cells.
Gallagher, H; Carroll, W M; Dowd, M; Rochev, Y
2008-01-01
The development of drug-eluting stents to combat the problem of in-stent restenosis has revolutionized interventional cardiology. However, concerns have emerged about the risk of late angiographic stent thromboses associated with drug-eluting stents. It has been shown that noncytotoxic concentrations of paclitaxel exert an antiangiogenic effect, suggesting that paclitaxel and similar agents may inhibit key cellular functions in a threshold-independent manner. In this study, the effect of vinblastine, an antimitotic drug, on endothelial cells is analyzed. It is investigated whether noncytotoxic concentrations of the drug could exert an antirestenotic effect. The change in levels of cell proliferation, activity, and viability in human umbilical vein endothelial cells was measured at a range of concentrations and over a number of time points. Also, the level of apoptotic activity in response to vinblastine was analyzed. This study shows that the concentration of vinblastine most appropriate in restenosis treatment would be between 0.1 and 1 nM. At this concentration, vinblastine exerts a distinct biological effect without causing an increase in apoptotic activity. These results emphasize the importance of finding an appropriate concentration window in order to minimize the risk of delayed endothelialization and thrombosis.
Effects of retinoic acids on the dendritic morphology of cultured hippocampal neurons.
Liu, Ying; Kagechika, Hiroyuki; Ishikawa, Junko; Hirano, Hitoshi; Matsukuma, Satoshi; Tanaka, Kazuko; Nakamura, Shoji
2008-08-01
Vitamin A-derived retinoic acids (RAs) are known to exert a variety of biological actions, including modulatory effects on cell differentiation and apoptosis. A recent study has demonstrated that 13-cis-RA and all-trans-RA suppressed neurogenesis in the dentate gyrus of the hippocampus in adult mice. The present experiments were performed to see whether 13-cis-RA and all-trans-RA could alter the dendritic morphology of cultured hippocampal neurons via RA receptors: retinoic acid receptor (RAR) and retinoid X receptor (RXR). High doses of 13-cis-RA and all-trans-RA exerted a negative effect on the cultured hippocampal neurons, while a low dose of 13-cis-RA but not all-trans-RA caused a positive effect. The negative changes induced by 13-cis-RA and all-trans-RA were antagonized by RXR antagonists and RAR antagonists, respectively. The positive changes induced by a low dose of 13-cis-RA were blocked by both RXR antagonists and RAR antagonists. These results suggest that RAs at high concentrations cause a negative effect on the dendritic morphology of cultured hippocampal neurons through RA receptors, while RAs at low concentrations exert a positive influence on cultured hippocampal neurons.
An, Yan; Chen, Chong; Inoue, Takeshi; Nakagawa, Shin; Kitaichi, Yuji; Wang, Ce; Izumi, Takeshi; Kusumi, Ichiro
2016-10-03
The functional role of serotonergic projections from the median raphe nucleus (MRN) to the dorsal hippocampus (DH) in anxiety remains understood poorly. The purpose of the present research was to examine the functional role of this pathway, using the contextual fear conditioning (CFC) model of anxiety. We show that intra-MRN microinjection of mirtazapine, a noradrenergic and specific serotonergic antidepressant, reduced freezing in CFC without affecting general motor activity dose-dependently, suggesting an anxiolytic-like effect. In addition, intra-MRN microinjection of mirtazapine dose-dependently increased extracellular concentrations of serotonin (5-HT) but not dopamine in the DH. Importantly, intra-DH pre-microinjection of WAY-100635, a 5-HT1A antagonist, significantly attenuated the effect of mirtazapine on freezing. These results, for the first time, suggest that activation of the MRN-DH 5-HT1A pathway exerts an anxiolytic-like effect in CFC. This is consistent with the literature that the hippocampus is essential for retrieval of contextual memory and that 5-HT1A receptor activation in the hippocampus primarily exerts an inhibitory effect on the neuronal activity. Copyright © 2016 Elsevier Inc. All rights reserved.
Sakata, Chinatsu; Kawasaki, Tomihisa; Kato, Yasuko; Abe, Masaki; Suzuki, Ken-ichi; Ohmiya, Makoto; Funatsu, Toshiyuki; Morita, Yoshiaki; Okada, Masamichi
2013-07-01
Aspirin inhibits both the cyclooxygenase (COX)-1-dependent production of thromboxane A2 (TXA2) in platelets and COX-2-dependent production of anti-aggregatory prostaglandin I2 (PGI2) in vessel walls, resulting in "aspirin dilemma." Our objective is to investigate whether ASP6537 can overcome aspirin dilemma and exert a potent antithrombotic effect without a concurrent ulcerogenic effect. We evaluated the inhibitory effects of ASP6537 on recombinant human COX-1 (rhCOX-1) and rhCOX-2 activities using a COX-1/2 selectivity test. To determine whether ASP6537 induces aspirin dilemma, we examined the effects of ASP6537 on in vitro TXA2 and PGI2 metabolite production from platelets and isolated aorta of guinea pigs, and on plasma concentrations of TXA2 and PGI2 metabolites in aged rats. Finally, we evaluated the antithrombotic effects and ulcerogenic activity of ASP6537 using an electrically induced carotid arterial thrombosis model and a gastric ulcer model in guinea pigs. The IC50 ratios of rhCOX-2 to rhCOX-1 for ASP6537 and aspirin were >142,000 and 1.63 fold, respectively. ASP6537 inhibited TXA2 production more selectively than aspirin in in vitro and in vivo TXA2/PGI2 production studies. ASP6537 exerted a significant antithrombotic effect at ≥3 mg/kg, while aspirin tended to inhibit thrombosis at 300 mg/kg but it was not statistically significant. Further, ASP6537 did not induce ulcer formation at 100 mg/kg, whereas aspirin exhibited an ulcerogenic effect at doses of ≥100 mg/kg. ASP6537 functions as a highly selective COX-1 inhibitor with a superior ability to aspirin for normalizing TXA2/PGI2 balance, and exerts antithrombotic effect without ulcerogenic effect. Copyright © 2013 Elsevier Ltd. All rights reserved.
Modeling of ion transport through a porous separator in vanadium redox flow batteries
NASA Astrophysics Data System (ADS)
Zhou, X. L.; Zhao, T. S.; An, L.; Zeng, Y. K.; Wei, L.
2016-09-01
In this work, we develop a two-dimensional, transient model to investigate the mechanisms of ion-transport through a porous separator in VRFBs and their effects on battery performance. Commercial-available separators with pore sizes of around 45 nm are particularly investigated and effects of key separator design parameters and operation modes are explored. We reveal that: i) the transport mechanism of vanadium-ion crossover through available separators is predominated by convection; ii) reducing the pore size below 15 nm effectively minimizes the convection-driven vanadium-ion crossover, while further reduction in migration- and diffusion-driven vanadium-ion crossover can be achieved only when the pore size is reduced to the level close to the sizes of vanadium ions; and iii) operation modes that can affect the pressure at the separator/electrode interface, such as the electrolyte flow rate, exert a significant influence on the vanadium-ion crossover rate through the available separators, indicating that it is critically important to equalize the pressure on each half-cell of a power pack in practical applications.
A face to remember: emotional expression modulates prefrontal activity during memory formation.
Sergerie, Karine; Lepage, Martin; Armony, Jorge L
2005-01-15
Emotion can exert a modulatory role on episodic memory. Several studies have shown that negative stimuli (e.g., words, pictures) are better remembered than neutral ones. Although facial expressions are powerful emotional stimuli and have been shown to influence perception and attention processes, little is known about their effect on memory. We used functional magnetic resonance imaging (fMRI) in humans to investigate the effects of expression (happy, neutral, and fearful) on prefrontal cortex (PFC) activity during the encoding of faces, using a subsequent memory effect paradigm. Our results show that activity in right PFC predicted memory for faces, regardless of expression, while a homotopic region in the left hemisphere was associated with successful encoding only for faces with an emotional expression. These findings are consistent with the proposed role of right dorsolateral PFC in successful encoding of nonverbal material, but also suggest that left DLPFC may be a site where integration of memory and emotional processes occurs. This study sheds new light on the current controversy regarding the hemispheric lateralization of PFC in memory encoding.
Punishment as a means of competition: implications for strong reciprocity theory.
Paál, Tünde; Bereczkei, Tamás
2015-01-01
Strong negative reciprocity, that is, sanctions imposed on norm violators at the punisher's own expense, has powerful cooperation-enhancing effects in both real-life and experimental game situations. However, it is plausible that punishment may obtain alternative roles depending on social context and the personality characteristics of participants. We examined the occurrence of punishing behavior among 80 subjects in a strongly competitive Public Goods game setting. Despite the punishment condition, the amount of the contributions decreased steadily during the game. The amount of contributions had no significant effect on received and imposed punishments. The results indicate that certain social contexts (in this case, intensive competition) exert modifying effects on the role that punishment takes on. Subjects punished each other in order to achieve a higher rank and a financially better outcome. Punishment primarily functioned as a means of rivalry, instead of as a way of second-order cooperation, as strong reciprocity suggests. These results indicate the need for the possible modification of the social conditions of punishment mechanisms described by the strong reciprocity theory as an evolutionary explanation of human cooperation.
Punishment as a Means of Competition: Implications for Strong Reciprocity Theory
Paál, Tünde; Bereczkei, Tamás
2015-01-01
Strong negative reciprocity, that is, sanctions imposed on norm violators at the punisher’s own expense, has powerful cooperation-enhancing effects in both real-life and experimental game situations. However, it is plausible that punishment may obtain alternative roles depending on social context and the personality characteristics of participants. We examined the occurrence of punishing behavior among 80 subjects in a strongly competitive Public Goods game setting. Despite the punishment condition, the amount of the contributions decreased steadily during the game. The amount of contributions had no significant effect on received and imposed punishments. The results indicate that certain social contexts (in this case, intensive competition) exert modifying effects on the role that punishment takes on. Subjects punished each other in order to achieve a higher rank and a financially better outcome. Punishment primarily functioned as a means of rivalry, instead of as a way of second-order cooperation, as strong reciprocity suggests. These results indicate the need for the possible modification of the social conditions of punishment mechanisms described by the strong reciprocity theory as an evolutionary explanation of human cooperation. PMID:25811464
Lynch, R J M; Navada, R; Walia, R
2004-01-01
To summarise support for current consensus on the likely means by which fluoride toothpastes reduce caries and review some relevant studies of the effect of low levels of fluoride on the demineralisation and remineralisation of enamel. The major anti-caries effect of fluoride toothpastes is thought to result from small but protracted elevations in levels of fluoride in plaque and saliva. Fluoride incorporated into enamel systemically does not reduce enamel solubility sufficiently to exert an anti-caries effect. Fluoride has the potential to exert an anti-caries benefit largely through three mechanisms; inhibition of demineralisation, promotion of remineralisation and interference with bacterial growth and metabolism. However, the low levels of fluoride thought to influence caries are insufficient to have a significant effect via the latter mechanism. Thus reductions in caries resulting from the use of fluoride toothpastes can be linked to modification of the demineralisation/remineralisation balance by direct effects on dental mineral exerted topically by low levels of fluoride. Numerous in vitro studies have shown that low levels of fluoride, typical of those found after many hours in resting plaque and saliva, and resulting from the regular use of fluoride toothpastes, can have a profound effect on enamel demineralisation and remineralisation.
Micucci, Matteo; Malaguti, Marco; Toschi, Tullia Gallina; Di Lecce, Giuseppe; Aldini, Rita; Angeletti, Andrea; Chiarini, Alberto; Budriesi, Roberta; Hrelia, Silvana
2015-01-01
This study was aimed at investigating the cardiovascular effects of an Olea europea L. leaf extract (OEE), of a Hibiscus sabdariffa L. flower extract (HSE), and of their 13 : 2 w/w mixture in order to assess their cardiac and vascular activity. Both extracts were fully characterized in their bioactive compounds by HPLC-MS/MS analysis. The study was performed using primary vascular endothelial cells (HUVECs) to investigate the antioxidant and cytoprotective effect of the extracts and their mixture and isolated guinea-pig left and right atria and aorta to evaluate the inotropic and chronotropic activities and vasorelaxant properties. In cultured HUVECs, OEE and HSE reduced intracellular reactive oxygen species formation and improved cell viability, following oxidative stress in dose-dependent manner. OEE and HSE exerted negative inotropic and vasorelaxant effects without any chronotropic property. Interestingly, the mixture exerted higher cytoprotective effects and antioxidant activities. Moreover, the mixture exerted an inotropic effect similar to each single extract, while it revealed an intrinsic negative chronotropic activity different from the single extract; its relaxant activity was higher than that of each single extract. In conclusion OEE and HSE mixture has a good potential for pharmaceutical and nutraceutical application, thanks to the synergistic effects of the single phytochemicals.
Micucci, Matteo; Gallina Toschi, Tullia; Di Lecce, Giuseppe; Aldini, Rita; Angeletti, Andrea; Chiarini, Alberto
2015-01-01
This study was aimed at investigating the cardiovascular effects of an Olea europea L. leaf extract (OEE), of a Hibiscus sabdariffa L. flower extract (HSE), and of their 13 : 2 w/w mixture in order to assess their cardiac and vascular activity. Both extracts were fully characterized in their bioactive compounds by HPLC-MS/MS analysis. The study was performed using primary vascular endothelial cells (HUVECs) to investigate the antioxidant and cytoprotective effect of the extracts and their mixture and isolated guinea-pig left and right atria and aorta to evaluate the inotropic and chronotropic activities and vasorelaxant properties. In cultured HUVECs, OEE and HSE reduced intracellular reactive oxygen species formation and improved cell viability, following oxidative stress in dose-dependent manner. OEE and HSE exerted negative inotropic and vasorelaxant effects without any chronotropic property. Interestingly, the mixture exerted higher cytoprotective effects and antioxidant activities. Moreover, the mixture exerted an inotropic effect similar to each single extract, while it revealed an intrinsic negative chronotropic activity different from the single extract; its relaxant activity was higher than that of each single extract. In conclusion OEE and HSE mixture has a good potential for pharmaceutical and nutraceutical application, thanks to the synergistic effects of the single phytochemicals. PMID:26180582
From professional monopoly to corporate oligopoly:the clinical laboratory industry in transition.
Bailey, R M
1977-02-01
Until the mid-1960s the nonhospital clinical laboratory industry was dominated by pathologists. The ethics of medical professionalism protected the pathologists' market from price competition and from any serious threat from new entrants into the market. Immune from the competitive pressures of the marketplace, pathologists exerted monopoly control in local markets. That power was eroded by laboratories operated by technologists and bioanalysts and was finally overcome by the entry of large corporations into the industry. The market power of the largest corporate laboratories is now growing to a point where competition may again be thwarted. The professional ethics of pathologists allowed high prices, but there was little push toward higher volume. The commercial ethics of the corporate entrants brought lower prices but resulted in strong pressure for greater test quantities. In either case, the power wielded by the dominant producer would seem to go against the consumer's interests.
Bood, Robert Jan; Nijssen, Marijn; van der Kamp, John; Roerdink, Melvyn
2013-01-01
Acoustic stimuli, like music and metronomes, are often used in sports. Adjusting movement tempo to acoustic stimuli (i.e., auditory-motor synchronization) may be beneficial for sports performance. However, music also possesses motivational qualities that may further enhance performance. Our objective was to examine the relative effects of auditory-motor synchronization and the motivational impact of acoustic stimuli on running performance. To this end, 19 participants ran to exhaustion on a treadmill in 1) a control condition without acoustic stimuli, 2) a metronome condition with a sequence of beeps matching participants’ cadence (synchronization), and 3) a music condition with synchronous motivational music matched to participants’ cadence (synchronization+motivation). Conditions were counterbalanced and measurements were taken on separate days. As expected, time to exhaustion was significantly longer with acoustic stimuli than without. Unexpectedly, however, time to exhaustion did not differ between metronome and motivational music conditions, despite differences in motivational quality. Motivational music slightly reduced perceived exertion of sub-maximal running intensity and heart rates of (near-)maximal running intensity. The beat of the stimuli –which was most salient during the metronome condition– helped runners to maintain a consistent pace by coupling cadence to the prescribed tempo. Thus, acoustic stimuli may have enhanced running performance because runners worked harder as a result of motivational aspects (most pronounced with motivational music) and more efficiently as a result of auditory-motor synchronization (most notable with metronome beeps). These findings imply that running to motivational music with a very prominent and consistent beat matched to the runner’s cadence will likely yield optimal effects because it helps to elevate physiological effort at a high perceived exertion, whereas the consistent and correct cadence induced by auditory-motor synchronization helps to optimize running economy. PMID:23951000
Bood, Robert Jan; Nijssen, Marijn; van der Kamp, John; Roerdink, Melvyn
2013-01-01
Acoustic stimuli, like music and metronomes, are often used in sports. Adjusting movement tempo to acoustic stimuli (i.e., auditory-motor synchronization) may be beneficial for sports performance. However, music also possesses motivational qualities that may further enhance performance. Our objective was to examine the relative effects of auditory-motor synchronization and the motivational impact of acoustic stimuli on running performance. To this end, 19 participants ran to exhaustion on a treadmill in 1) a control condition without acoustic stimuli, 2) a metronome condition with a sequence of beeps matching participants' cadence (synchronization), and 3) a music condition with synchronous motivational music matched to participants' cadence (synchronization+motivation). Conditions were counterbalanced and measurements were taken on separate days. As expected, time to exhaustion was significantly longer with acoustic stimuli than without. Unexpectedly, however, time to exhaustion did not differ between metronome and motivational music conditions, despite differences in motivational quality. Motivational music slightly reduced perceived exertion of sub-maximal running intensity and heart rates of (near-)maximal running intensity. The beat of the stimuli -which was most salient during the metronome condition- helped runners to maintain a consistent pace by coupling cadence to the prescribed tempo. Thus, acoustic stimuli may have enhanced running performance because runners worked harder as a result of motivational aspects (most pronounced with motivational music) and more efficiently as a result of auditory-motor synchronization (most notable with metronome beeps). These findings imply that running to motivational music with a very prominent and consistent beat matched to the runner's cadence will likely yield optimal effects because it helps to elevate physiological effort at a high perceived exertion, whereas the consistent and correct cadence induced by auditory-motor synchronization helps to optimize running economy.
Al-Sayed, Eman; El-Naga, Reem N
2015-01-15
The gastroprotective activity of an ellagitannin-rich fraction obtained from Eucalyptus citriodora (ECF) was investigated against ethanol-induced gastric ulceration in rats. The rats were pretreated with ECF (25, 50 and 100mg/kg) 1h before the administration of absolute ethanol to induce acute gastric ulceration. The gastric lesions were significantly reduced by all doses of ECF. Notably, pre-treatment with ECF (100mg/kg) conferred 99.6% gastroprotection, which is significantly higher than that produced by omeprazole. Moreover, ECF administration markedly increased the mucin content in a dose-dependent manner. The potent gastroprotective effect of ECF could be partly mediated by attenuating ethanol-induced oxidative stress. ECF-pre-treatment markedly increased the depleted GSH and SOD levels in a dose-dependent manner. Moreover, ECF significantly decreased the elevated MDA tissue levels induced by ethanol administration. The results demonstrated that ECF administration exerted a powerful anti-inflammatory activity as evidenced by the reduction in the pro-inflammatory markers; IL-1β, TNF-α, 5-LO and COX-2. Additionally, the caspase-3 tissue levels were significantly reduced in the groups pre-treated with ECF. These results suggest that ECF could exert a beneficial gastroprotective effect through their antioxidant, anti-inflammatory and anti-apoptotic properties. Furthermore, ECF pre-treatment significantly attenuated the ethanol-induced decrease in CGRP expression, which has a protective role against gastric ulceration. Histopathological examination revealed intact mucosal layer, absence of hemorrhage and necrosis in groups treated with ECF. Ellagitannins were identified as the major active constituents responsible for the marked antioxidant and gastroprotective properties of ECF. The HPLC-PDA-ESI/MS/MS technique was employed to identify the ellagitannins of E. citriodora. Copyright © 2014 Elsevier GmbH. All rights reserved.
de Oliveira, Marcos Roberto; Nabavi, Seyed Fazel; Manayi, Azadeh; Daglia, Maria; Hajheydari, Zohreh; Nabavi, Seyed Mohammad
2016-04-01
Mitochondria, the power plants of the cell, are known as a cross-road of different cellular signaling pathways. These cytoplasmic double-membraned organelles play a pivotal role in energy metabolism and regulate calcium flux in the cells. It is well known that mitochondrial dysfunction is associated with different diseases such as neurodegeneration and cancer. A growing body of literature has shown that polyphenolic compounds exert direct effects on mitochondrial ultra-structure and function. Resveratrol is known as one of the most common bioactive constituents of red wine, which improves mitochondrial functions under in vitro and in vivo conditions. This paper aims to review the molecular pathways underlying the beneficial effects of resveratrol on mitochondrial structure and functions. In addition, we discuss the chemistry and main sources of resveratrol. Resveratrol represents the promising effects on mitochondria in different experimental models. However, there are several reports on the detrimental effects elicited by resveratrol on mitochondria. An understanding of the chemistry and source of resveratrol, its bioavailability and the promising effects on mitochondria brings a new hope to therapy of mitochondrial dysfunction-related diseases. Copyright © 2016 Elsevier B.V. All rights reserved.
Cuomo, Peter
2005-01-01
In the biotechnology field, researchers often face complex moral and social issues while pursuing their scientific goals. Congress may regulate much of that research by debating the issues and placing restraints on funding granted by the government. In modern times, our presidents have also made some of those funding decisions through the issuance of executive orders. Presidents may issue executive orders with binding legal effect, despite having little constitutional authority to do so. Unless a new president takes office, only Congress or the courts can invalidate an executive order. In the regulation-sensitive biotechnology industry, presidents may exert profound influence by announcing executive orders. Former President Clinton and President George W. Bush are just the latest presidents who have used such orders to influence biotechnology as they have deemed appropriate. In doing so, those presidents have assumed a degree of unilateral lawmaking power over an industry that is fundamentally important to every citizen. This article stresses the need for the other branches of our government to discontinue granting unconstitutional legislative power to the president, and bring more social and scientific balance to important biotechnology policy decisions.
Is There Evidence that Runners can Benefit from Wearing Compression Clothing?
Engel, Florian Azad; Holmberg, Hans-Christer; Sperlich, Billy
2016-12-01
Runners at various levels of performance and specializing in different events (from 800 m to marathons) wear compression socks, sleeves, shorts, and/or tights in attempt to improve their performance and facilitate recovery. Recently, a number of publications reporting contradictory results with regard to the influence of compression garments in this context have appeared. To assess original research on the effects of compression clothing (socks, calf sleeves, shorts, and tights) on running performance and recovery. A computerized research of the electronic databases PubMed, MEDLINE, SPORTDiscus, and Web of Science was performed in September of 2015, and the relevant articles published in peer-reviewed journals were thus identified rated using the Physiotherapy Evidence Database (PEDro) Scale. Studies examining effects on physiological, psychological, and/or biomechanical parameters during or after running were included, and means and measures of variability for the outcome employed to calculate Hedges'g effect size and associated 95 % confidence intervals for comparison of experimental (compression) and control (non-compression) trials. Compression garments exerted no statistically significant mean effects on running performance (times for a (half) marathon, 15-km trail running, 5- and 10-km runs, and 400-m sprint), maximal and submaximal oxygen uptake, blood lactate concentrations, blood gas kinetics, cardiac parameters (including heart rate, cardiac output, cardiac index, and stroke volume), body and perceived temperature, or the performance of strength-related tasks after running. Small positive effect sizes were calculated for the time to exhaustion (in incremental or step tests), running economy (including biomechanical variables), clearance of blood lactate, perceived exertion, maximal voluntary isometric contraction and peak leg muscle power immediately after running, and markers of muscle damage and inflammation. The body core temperature was moderately affected by compression, while the effect size values for post-exercise leg soreness and the delay in onset of muscle fatigue indicated large positive effects. Our present findings suggest that by wearing compression clothing, runners may improve variables related to endurance performance (i.e., time to exhaustion) slightly, due to improvements in running economy, biomechanical variables, perception, and muscle temperature. They should also benefit from reduced muscle pain, damage, and inflammation.
Brandon-Warner, Elizabeth; Eheim, Ashley L; Foureau, David M; Walling, Tracy L; Schrum, Laura W; McKillop, Iain H
2012-01-01
Hepatocellular carcinoma (HCC) is a global health burden with limited treatment options and poor prognosis. Silibinin, an antioxidant derived from the Milk Thistle plant (Silybum marianum), is reported to exert hepatoprotective and antitumorigenic effects in vitro and in vivo by suppressing oxidative stress and proliferation. Using a DEN-initiated mouse model of HCC, this study examined the effects of dietary silibinin supplementation alone, or in combination with chronic ethanol consumption on HCC progression. Our data demonstrate silibinin exerted marginal hepatoprotective effects in early stages of hepatocarcinogenesis but, when co-administered with ethanol, exacerbated the promotional effects of ethanol in HCC bearing mice, but only in males. PMID:22863537
Brandon-Warner, Elizabeth; Eheim, Ashley L; Foureau, David M; Walling, Tracy L; Schrum, Laura W; McKillop, Iain H
2012-12-29
Hepatocellular carcinoma (HCC) is a global health burden with limited treatment options and poor prognosis. Silibinin, an antioxidant derived from the Milk Thistle plant (Silybum marianum), is reported to exert hepatoprotective and antitumorigenic effects in vitro and in vivo by suppressing oxidative stress and proliferation. Using a DEN-initiated mouse model of HCC, this study examined the effects of dietary silibinin supplementation alone, or in combination with chronic ethanol consumption on HCC progression. Our data demonstrate silibinin exerted marginal hepatoprotective effects in early stages of hepatocarcinogenesis but, when co-administered with ethanol, exacerbated the promotional effects of ethanol in HCC bearing mice, but only in males. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
Hayati, Davood; Charkhabi, Morteza; Naami, Abdolzahra
2014-01-14
The aim of this study was to determine the effects of transformational leadership and its components on work engagement among hospital nurses. There are a few set of researches that have focused on the effects of transformational leadership on work engagement in nurses. A descriptive, correlational, cross-sectional design was used. In this study, 240 nurses have been chosen by stratified random sampling method which filled related self-reported scales include multifactor leadership questionnaire (MLQ) and work engagement scale. Data analysis has been exerted according to the statistical method of simple and multiple correlation coefficients. Findings indicated that the effect of this type of leadership on work engagement and its facets is positive and significant. In addition, the research illustrates that transformational leaders transfer their enthusiasm and high power to their subordinates by the way of modeling. This manner can increase the power as a component of work engagement in workers. Idealized influence among these leaders can result in forming a specific belief among employees toward those leaders and leaders can easily transmit their inspirational motivation to them. Consequently, it leads to make a positive vision by which, and by setting high standards, challenges the employees and establishes zeal along with optimism for attaining success in works. regarding to the results we will expand leadership and work engagement literature in hospital nurses. Also, we conclude with theoretical and practical implications and propose a clear horizon for future researches.
Ding, Zhen; Li, Jintao; Li, Fan; Mephryar, Mohammadreza Mohammadzad; Wu, Shuicai; Zhang, Chen; Zeng, Yi
2017-01-01
The extremely low-frequency electromagnetic field (ELF-EMF), mainly emitted by electric transmission lines and household electronic appliances, is becoming a worldwide health risk. It is imperative to investigate the biological impacts of ELF-EMF and to identify products that are resistant to the radiation from 50 Hz ELF-EMF. In this study, we investigated the biological impacts of apoptosis caused by 50 Hz Power line ELF-EMF and the protective effects of Vit C and Vit E. We conducted this study in Beijing, China in 2013. B 95-8 and Balb/c-3T3 cells were divided into a sham group, an expo group and 3 expo groups in which the cells were preincubated with various concentrations of Vit C and Vit E. Then, all of the cells were exposed to 50 Hz Power line ELF-EMF and examined for apoptosis. The cells were collected for apoptosis detection after exposure. The percent of cells that undergoing apoptosis and preincubated with various concentrations of Vit C and Vit E were significantly lower than in the Expo group. Vit C and Vit E exert significant protective effects from 50 Hz ELF-EMF radiation. The optimal protective concentrations of Vit C and Vit E are 10 μmol/L and 25 μmol/L, respectively. The protective effect of vitamins was more apparent for Balb/c-3T3 cells than B 95-8 cells.
Rolling resistance and propulsion efficiency of manual and power-assisted wheelchairs.
Pavlidou, Efthymia; Kloosterman, Marieke G M; Buurke, Jaap H; Rietman, Johan S; Janssen, Thomas W J
2015-11-01
Rolling resistance is one of the main forces resisting wheelchair propulsion and thus affecting stress exerted on the upper limbs. The present study investigates the differences in rolling resistance, propulsion efficiency and energy expenditure required by the user during power-assisted and manual propulsion. Different tire pressures (50%, 75%, 100%) and two different levels of motor assistance were tested. Drag force, energy expenditure and propulsion efficiency were measured in 10 able-bodied individuals under different experimental settings on a treadmill. Results showed that drag force levels were significantly higher in the 50%, compared to the 75% and 100% inflation conditions. In terms of wheelchair type, the manual wheelchair displayed significantly lower drag force values than the power-assisted one. The use of extra-power-assisted wheelchair appeared to be significantly superior to conventional power-assisted and manual wheelchairs concerning both propulsion efficiency and energy expenditure required by the user. Overall, the results of the study suggest that the use of power-assisted wheelchair was more efficient and required less energy input by the user, depending on the motor assistance provided. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.
Chow, Amy Y; Dickerson, Clark R
2016-04-01
Pushing and pulling are common occupational exertions that are increasingly associated with musculoskeletal complaints. This study focuses on the sensitivity of shoulder capacity to gender, handle height, exertion type (push or pull) and handle orientation for these tasks. All factors except for handle orientation influenced unilateral and total manual force strength (p < 0.01), with exertion type being the most influential. Interaction effects also existed between handle height and exertion type. Additionally, joint moments at the shoulders and low back were influenced by all factors studied (p < 0.01), with exertion type again being most influential. Knowledge of the relative influence of multiple factors on shoulder capacity can provide guidance regarding these factors when designing or evaluating occupational pushing and pulling tasks for a diverse population. Practitioner Summary: pushing and pulling comprise nearly half of all manual materials handling tasks. Practitioners often assess, design or modify these tasks while incorporating constraints, including manual force direction and handle interface. This study provides guidance to aid design of pushing and pulling tasks in the context of shoulder physical capacity.
Tolerability to prolonged lifting tasks. A validation of the recommended limits.
Capodaglio, P; Bazzini, G
1997-01-01
Prolonged physical exertion is subjectively regulated by the perception of effort. This preliminary study was conducted to validate the use of subjective perceptions of effort in assessing objectively tolerable workloads for prolonged lifting tasks. Ten healthy male subjects tested their maximal lifting capacity (MLC) on a lift dynamometer (LidoLift, Loredan Biomed., West Sacramento, CA) and underwent incremental and 30-minute endurance lifting tests. Cardiorespiratory parameters were monitored with an oxygen uptake analyzer, mechanical parameters were calculated using a computerized dynamometer. Ratings of perceived exertion were given on Borg's 10-point scale. Physiological responses to repetitive lifting were matched with subjective perceptions. A single-variable statistical regression for power functions was performed to obtain the individual "iso-perception" curves as functions of the mechanical work exerted. We found that the "iso-perception" curve corresponding to a "moderate" perception of effort may represent the individual "tolerance threshold" for prolonged lifting tasks, since physiological responses at this level of intensity did not change significantly and the respiratory exchange ratio was less than one. The individually tolerable weight for lifting tasks lasting 30 min has been expressed as a percentage of the isoinertial MLC value and compared with the currently recommended limits for prolonged lifting tasks (Italian legislation D.L. 626/94). On the basis of our preliminary results a "tolerance threshold" of 20% MLC has been proposed for prolonged lifting tasks.
Ahmad, Imran
2018-01-01
This research study aims at addressing the paradigm of whole body fatigue and local muscle fatigue detection for squat lifting. For this purpose, a comparison was made between perceived exertion with the heart rate and normalized mean power frequency (NMPF) of eight major muscles. The sample consisted of 25 healthy males (age: 30 ± 2.2 years). Borg’s CR-10 scale was used for perceived exertion for two segments of the body (lower and upper) and the whole body. The lower extremity of the body was observed to be dominant compared to the upper and whole body in perceived response. First mode of principal component analysis (PCA) was obtained through the covariance matrix for the eight muscles for 25 subjects for NMPF of eight muscles. The diagonal entries in the covariance matrix were observed for each muscle. The muscle with the highest absolute magnitude was observed across all the 25 subjects. The medial deltoid and the rectus femoris muscles were observed to have the highest frequency for each PCA across 25 subjects. The rectus femoris, having the highest counts in all subjects, validated that the lower extremity dominates the sense of whole body fatigue during squat lifting. The findings revealed that it is significant to take into account the relation between perceived and measured effort that can help prevent musculoskeletal disorders in repetitive occupational tasks. PMID:29670002
Barwood, M J; Corbett, J; Thomas, K; Twentyman, P
2015-06-01
L-menthol stimulates cutaneous thermoreceptors and induces cool sensations improving thermal comfort, but has been linked to heat storage responses; this could increase risk of heat illness during self-paced exercise in the heat. Therefore, L-menthol application could lead to a discrepancy between behavioral and autonomic thermoregulatory drivers. Eight male participants volunteered. They were familiarized and then completed two trials in hot conditions (33.5 °C, 33% relative humidity) where their t-shirt was sprayed with CONTROL-SPRAY or MENTHOL-SPRAY after 10 km (i.e., when they were hot and uncomfortable) of a 16.1-km cycling time trial (TT). Thermal perception [thermal sensation (TS) and comfort (TC)], thermal responses [rectal temperature (Trec ), skin temperature (Tskin )], perceived exertion (RPE), heart rate, pacing (power output), and TT completion time were measured. MENTHOL-SPRAY made participants feel cooler and more comfortable and resulted in lower RPE (i.e., less exertion) yet performance was unchanged [TT completion: CONTROL-SPRAY 32.4 (2.9) and MENTHOL-SPRAY 32.7 (3.0) min]. Trec rate of increase was 1.40 (0.60) and 1.45 (0.40) °C/h after CONTROL-SPRAY and MENTHOL-SPRAY application, which were not different. Spraying L-menthol toward the end of self-paced exercise in the heat improved perception, but did not alter performance and did not increase heat illness risk. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Effects of Intermittent Neck Cooling During Repeated Bouts of High-Intensity Exercise
Galpin, Andrew J.; Bagley, James R.; Whitcomb, Blake; Wiersma, Leonard D.; Rosengarten, Jakob; Coburn, Jared W.; Judelson, Daniel A.
2016-01-01
The purpose of this investigation was to determine the influence of intermittent neck cooling during exercise bouts designed to mimic combat sport competitions. Participants (n = 13, age = 25.3 ± 5.0 year height = 176.9 ± 7.5 cm, mass = 79.3 ± 9.0 kg, body fat = 11.8% ± 3.1%) performed three trials on a cycle ergometer. Each trial consisted of two, 5-min high-intensity exercise (HEX) intervals (HEX1 and HEX2—20 s at 50% peak power, followed by 15 s of rest), and a time to exhaustion (TTE) test. One-minute rest intervals were given between each round (RI1 and RI2), during which researchers treated the participant’s posterior neck with either (1) wet-ice (ICE); (2) menthol spray (SPRAY); or (3) no treatment (CON). Neck (TNECK) and chest (TCHEST) skin temperatures were significantly lower following RI1 with ICE (vs. SPRAY). Thermal sensation decreased with ICE compared to CON following RI1, RI2, TTE, and a 2-min recovery. Rating of perceived exertion was also lower with ICE following HEX2 (vs. CON) and after RI2 (vs. SPRAY). Treatment did not influence TTE (68.9 ± 18.9s). The ability of intermittent ICE to attenuate neck and chest skin temperature rises during the initial HEX stages likely explains why participants felt cooler and less exerted during equivalent HEX bouts. These data suggest intermittent ICE improves perceptual stress during short, repeated bouts of vigorous exercise.
Scharinger, Mathias; Monahan, Philip J; Idsardi, William J
2016-03-01
While previous research has established that language-specific knowledge influences early auditory processing, it is still controversial as to what aspects of speech sound representations determine early speech perception. Here, we propose that early processing primarily depends on information propagated top-down from abstractly represented speech sound categories. In particular, we assume that mid-vowels (as in 'bet') exert less top-down effects than the high-vowels (as in 'bit') because of their less specific (default) tongue height position as compared to either high- or low-vowels (as in 'bat'). We tested this assumption in a magnetoencephalography (MEG) study where we contrasted mid- and high-vowels, as well as the low- and high-vowels in a passive oddball paradigm. Overall, significant differences between deviants and standards indexed reliable mismatch negativity (MMN) responses between 200 and 300ms post-stimulus onset. MMN amplitudes differed in the mid/high-vowel contrasts and were significantly reduced when a mid-vowel standard was followed by a high-vowel deviant, extending previous findings. Furthermore, mid-vowel standards showed reduced oscillatory power in the pre-stimulus beta-frequency band (18-26Hz), compared to high-vowel standards. We take this as converging evidence for linguistic category structure to exert top-down influences on auditory processing. The findings are interpreted within the linguistic model of underspecification and the neuropsychological predictive coding framework. Copyright © 2016 Elsevier Inc. All rights reserved.
Bonacci, Jason; Vleck, Veronica; Saunders, Philo U; Blanch, Peter; Vicenzino, Bill
2013-01-01
To determine which commonly measured variables of cycling intensity are related to subsequent running economy in triathletes. Cross-sectional laboratory study. Running economy was compared between a control run (no preceding cycle) and a run performed after a 45 min high-intensity cycle in eighteen triathletes. Power output, heart rate, rating of perceived exertion (RPE) and blood lactate concentration were monitored throughout the cycle. The relationship between measures of cycle intensity and the change in running economy was evaluated using Pearson's product moment correlation. Changes in running economy were also interpreted using the smallest worthwhile change (>2.4%) and grouped accordingly (i.e. impaired, no change, or improved running economy). Triathletes' RPE at the end of the cycling bout was significantly associated with the change in running economy after cycling (r=0.57, p=0.01). Average RPE of the cycle bout and RPE at the end of the cycling bout were significantly different between groups, with higher RPE scores being related to impairments in running economy (p=0.04 and p=0.02 respectively). RPE during cycling is associated with subsequent running economy in triathletes. RPE is a simple, cost-effective measure that triathletes and their coaches can use in competition and training to control cycling intensity without the need for specialist equipment such as crank systems or blood analysers. Copyright © 2012 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
Wein, Sharon; Taudon, Nicolas; Maynadier, Marjorie; Tran Van Ba, Christophe; Margout, Delphine; Bordat, Yann; Fraisse, Laurent; Wengelnik, Kai; Cerdan, Rachel; Bressolle-Gomeni, Françoise; Vial, Henri J
2017-08-01
Albitiazolium is the lead compound of bisthiazolium choline analogues and exerts powerful in vitro and in vivo antimalarial activities. Here we provide new insight into the fate of albitiazolium in vivo in mice and how it exerts its pharmacological activity. We show that the drug exhibits rapid and potent activity and has very favorable pharmacokinetic and pharmacodynamic properties. Pharmacokinetic studies in Plasmodium vinckei -infected mice indicated that albitiazolium rapidly and specifically accumulates to a great extent (cellular accumulation ratio, >150) in infected erythrocytes. Unexpectedly, plasma concentrations and the area under concentration-time curves increased by 15% and 69% when mice were infected at 0.9% and 8.9% parasitemia, respectively. Albitiazolium that had accumulated in infected erythrocytes and in the spleen was released into the plasma, where it was then available for another round of pharmacological activity. This recycling of the accumulated drug, after the rupture of the infected erythrocytes, likely extends its pharmacological effect. We also established a new viability assay in the P. vinckei -infected mouse model to discriminate between fast- and slow-acting antimalarials. We found that albitiazolium impaired parasite viability in less than 6 and 3 h at the ring and late stages, respectively, while parasite morphology was affected more belatedly. This highlights that viability and morphology are two parameters that can be differentially affected by a drug treatment, an element that should be taken into account when screening new antimalarial drugs. Copyright © 2017 American Society for Microbiology.
Does energy consumption contribute to environmental pollutants? Evidence from SAARC countries.
Akhmat, Ghulam; Zaman, Khalid; Shukui, Tan; Irfan, Danish; Khan, Muhammad Mushtaq
2014-05-01
The objective of the study is to examine the causal relationship between energy consumption and environmental pollutants in selected South Asian Association for Regional Cooperation (SAARC) countries, namely, Bangladesh, India, Nepal, Pakistan, and Srilanka, over the period of 1975-2011. The results indicate that energy consumption acts as an important driver to increase environmental pollutants in SAARC countries. Granger causality runs from energy consumption to environmental pollutants, but not vice versa, except carbon dioxide (CO2) emissions in Nepal where there exists a bidirectional causality between CO2 and energy consumption. Methane emissions in Bangladesh, Pakistan, and Srilanka and extreme temperature in India and Srilanka do not Granger cause energy consumption via both routes, which holds neutrality hypothesis. Variance decomposition analysis shows that among all the environmental indicators, CO2 in Bangladesh and Nepal exerts the largest contribution to changes in electric power consumption. Average precipitation in India, methane emissions in Pakistan, and extreme temperature in Srilanka exert the largest contribution.
Kapellusch, Jay M.; Garg, Arun; Bao, Stephen S.; Silverstein, Barbara A.; Burt, Susan E.; Dale, Ann Marie; Evanoff, Bradley A.; Gerr, Frederic E.; Harris-Adamson, Carisa; Hegmann, Kurt T.; Merlino, Linda A.; Rempel, David M.
2015-01-01
Pooling data from different epidemiological studies of musculoskeletal disorders (MSDs) is necessary to improve statistical power and to more precisely quantify exposure–response relationships for MSDs. The pooling process is difficult and time-consuming, and small methodological differences could lead to different exposure–response relationships. A subcommittee of a six-study research consortium studying carpal tunnel syndrome: (i) visited each study site, (ii) documented methods used to collect physical exposure data and (iii) determined compatibility of exposure variables across studies. Certain measures of force, frequency of exertion and duty cycle were collected by all studies and were largely compatible. A portion of studies had detailed data to investigate simultaneous combinations of force, frequency and duration of exertions. Limited compatibility was found for hand/wrist posture. Only two studies could calculate compatible Strain Index scores, but Threshold Limit Value for Hand Activity Level could be determined for all studies. Challenges of pooling data, resources required and recommendations for future researchers are discussed. PMID:23697792
Takahashi, Koki; Osada, Kyoichi
2017-05-01
We previously showed that xanthohumol-rich hop extract (XRHE, ~18% xanthohumol) exerts anti-obesity effects in rats fed a high-fat diet through regulation of fatty acid metabolism. In this study, we examined the effects of dietary purified xanthohumol from XRHE (PX, ~91.9% xanthohumol) in KK-Ay mice in order to understand the anti-obesity effects of xanthohumol alone because XRHE contains 82% unknown compounds. Dietary consumption of PX significantly inhibited an increase in the visceral fat weight of mice compared to those fed control diet without PX. Plasma leptin level was significantly lower in the PX-fed group than in the control group. Dietary PX lowered hepatic fatty acid synthesis by down-regulation of SREBP1c mRNA expression in the liver. On the other hand, fatty acid β-oxidation in the liver was promoted by dietary PX through the up-regulation of PPARα mRNA expression. Moreover, the fecal levels of fatty acids and carbohydrates increased by dietary PX. PX inhibited lipase or α-amylase activity in vitro. Thus, we found that PX may exert anti-obesity effects through the regulation of lipid metabolism and inhibition of intestinal fat and carbohydrate absorption, and that xanthohumol alone may exert anti-obesity effects.
Soberón, José R; Sgariglia, Melina A; Pastoriza, Ana C; Soruco, Estela M; Jäger, Sebastián N; Labadie, Guillermo R; Sampietro, Diego A; Vattuone, Marta A
2017-05-05
Anagallis arvensis L. (Primulaceae) is used in argentinean northwestern traditional medicine to treat fungal infections. We are reporting the isolation and identification of compounds with antifungal activity against human pathogenic yeast Candida albicans, and toxicity evaluation. to study the antifungal activity of extracts and purified compounds obtained form A. arvensis aerial parts, alone and in combinations with fluconazole (FLU), and to study the toxicity of the active compounds. Disk diffusion assays were used to perform an activity-guided isolation of antifungal compounds from the aerial parts of A. arvensis. Broth dilution checkerboard and viable cell count assays were employed to determine the effects of samples and combinations of FLU + samples against Candida albicans. The chemical structures of active compounds were elucidated by spectroscopic analysis. Genotoxic and haemolytic effects of the isolated compounds were determined. Four triterpenoid saponins (1-4) were identified. Anagallisin C (AnC), exerted the highest inhibitory activity among the assayed compounds against C. albicans reference strain (ATCC 10231), with MIC-0 =1µg/mL. The Fractional Inhibitory Concentration Index (FICI=0.129) indicated a synergistic effect between AnC (0.125µg/mL) and FLU (0.031µg/mL) against C. albicans ATCC 10231. AnC inhibited C. albicans 12-99 FLU resistant strain (MIC-0 =1µg/mL), and the FICI=0.188 indicated a synergistic effect between AnC (0.125µg/mL) and fluconazole (16µg/mL). The combination AnC+ FLU exerted fungicidal activity against both C. albicans strains. AnC exerted inhibitory activity against C. albicans ATCC 10231 sessile cells (MIC 5 0=0.5µg/mL and MIC 80 =1µg/mL) and against C. albicans 12-99 sessile cells (MIC 5 0=0.75µg/mL and MIC 80 =1.25µg/mL). AnC exerted haemolytic effect against human red blood cells at 15µg/mL and did not exerted genotoxic effect on Bacillus subtilis rec strains. The antifungal activity and lack of genotoxic effects of AnC give support to the traditional use of A. arvensis as antifungal and makes AnC a compound of interest to expand the available antifungal drugs. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.
Tomography of a Probe Potential Using Atomic Sensors on Graphene.
Wyrick, Jonathan; Natterer, Fabian D; Zhao, Yue; Watanabe, Kenji; Taniguchi, Takashi; Cullen, William G; Zhitenev, Nikolai B; Stroscio, Joseph A
2016-12-27
Our ability to access and explore the quantum world has been greatly advanced by the power of atomic manipulation and local spectroscopy with scanning tunneling and atomic force microscopes, where the key technique is the use of atomically sharp probe tips to interact with an underlying substrate. Here we employ atomic manipulation to modify and quantify the interaction between the probe and the system under study that can strongly affect any measurement in low charge density systems, such as graphene. We transfer Co atoms from a graphene surface onto a probe tip to change and control the probe's physical structure, enabling us to modify the induced potential at a graphene surface. We utilize single Co atoms on a graphene field-effect device as atomic scale sensors to quantitatively map the modified potential exerted by the scanning probe over the whole relevant spatial and energy range.
Neurobiology of Schemas and Schema-Mediated Memory.
Gilboa, Asaf; Marlatte, Hannah
2017-08-01
Schemas are superordinate knowledge structures that reflect abstracted commonalities across multiple experiences, exerting powerful influences over how events are perceived, interpreted, and remembered. Activated schema templates modulate early perceptual processing, as they get populated with specific informational instances (schema instantiation). Instantiated schemas, in turn, can enhance or distort mnemonic processing from the outset (at encoding), impact offline memory transformation and accelerate neocortical integration. Recent studies demonstrate distinctive neurobiological processes underlying schema-related learning. Interactions between the ventromedial prefrontal cortex (vmPFC), hippocampus, angular gyrus (AG), and unimodal associative cortices support context-relevant schema instantiation and schema mnemonic effects. The vmPFC and hippocampus may compete (as suggested by some models) or synchronize (as suggested by others) to optimize schema-related learning depending on the specific operationalization of schema memory. This highlights the need for more precise definitions of memory schemas. Copyright © 2017 Elsevier Ltd. All rights reserved.
Flywheel Energy Storage System Suspended by Hybrid Magnetic Bearing
NASA Astrophysics Data System (ADS)
Owusu-Ansah, Prince; Hu, Yefa; Misbawu, Adam
This work presents a prototype flywheel energy storage system (FESS) suspended by hybrid magnetic bearing (HMB) rotating at a speed of 20000rpm with a maximum storage power capacity of 30W with a maximum tip speed of 300m/s. The design presented is an improvement of most existing FESS, as the design incorporates a unique feature in that the upper and the lower rotor and stator core are tapered which enhances larger thrust and much lower radial force to be exerted on the system. Without any adverse effect being experienced by the model. The work also focuses on the description of developing a prototype FESS suspended by HMB using solid works as a basis of developing in the nearer future a more improved FESS suspended by HMB capable of injecting the ever increasing high energy demand situation in the 21st century and beyond.
Mass enhances speed but diminishes turn capacity in terrestrial pursuit predators.
Wilson, Rory P; Griffiths, Iwan W; Mills, Michael G L; Carbone, Chris; Wilson, John W; Scantlebury, David M
2015-08-07
The dynamics of predator-prey pursuit appears complex, making the development of a framework explaining predator and prey strategies problematic. We develop a model for terrestrial, cursorial predators to examine how animal mass modulates predator and prey trajectories and affects best strategies for both parties. We incorporated the maximum speed-mass relationship with an explanation of why larger animals should have greater turn radii; the forces needed to turn scale linearly with mass whereas the maximum forces an animal can exert scale to a 2/3 power law. This clarifies why in a meta-analysis, we found a preponderance of predator/prey mass ratios that minimized the turn radii of predators compared to their prey. It also explained why acceleration data from wild cheetahs pursuing different prey showed different cornering behaviour with prey type. The outcome of predator prey pursuits thus depends critically on mass effects and the ability of animals to time turns precisely.
NASA Technical Reports Server (NTRS)
Roithmayr, Carlos M.
1999-01-01
The Attitude Control and Energy Storage Experiment is currently under development for the International Space Station; two counter-rotating flywheels will be levitated with magnetic bearings and placed in vacuum housings. The primary objective of the experiment is to store and discharge energy, in combination with existing batteries, into the electrical power system. The secondary objective is to use the flywheels to exert torque on the Station; a simple torque profile has been designed so that the Station's Control Moment Gyroscopes will be assisted in maintaining torque equilibrium attitude. Two energy storage contingencies could result in the inadvertent application of torque by the flywheels to the Station: an emergency shutdown of one flywheel rotor while the other remains spinning, and energy storage with only one rotor instead of the counterrotating pair. Analysis of these two contingencies shows that attitude control and the microgravity environment will not be adversely affected.
Decrease of contact resistance at the interface of carbon nanotube/electrode by nanowelding
NASA Astrophysics Data System (ADS)
Zhao, Bo; Wang, Yanfang; Zhang, Yafei
2017-03-01
Reliable interconnection between carbon nanotubes (CNTs) and external circuit is one of the prerequisite in CNT electronics. In this work, ultrasonic nanowelding was used to bond CNTs with metal electrodes. By exerting ultrasonic energy at the interface of CNT/electrode, a reliable joint with negligible contact resistance was obtained between CNTs and electrodes. The performance of welding is susceptible to the ultrasonic parameters such as ultrasonic power and clamping force, as well as the metal type. It is found that the metals with good ductility or low melting point are easier to achieve effective joints. Moreover, interfacial compounds are formed at the welded surface of metal Al and Fe, which is resulted from the interacting and chemical bonding of carbon and metal atoms. After nanowelding, the contact resistance between CNTs and electrode is decreased dramatically, and the two-terminal resistance of the sample approximates to the intrinsic resistance of the CNT itself.
Bistetrazine-cyanines as double-clicking fluorogenic two-point binder or crosslinker probes.
Kormos, Attila; Koehler, Christine; Fodor, Eszter; Rutkai, Zsófia; Martin, Maddison; Mező, Gábor; Lemke, Edward; Kele, Péter
2018-04-20
Fluorogenic probes are capable of minimizing background fluorescence of unreacted and non-specifically adsorbed reagents. The preceding years have brought substantial developments in the design and synthesis of bioorthogonally applicable fluorogenic systems mainly based on the quenching effects of azide and tetrazine moieties. The modulation power exerted by these bioorthogonal motifs typically becomes less efficient on more conjugated systems, i.e. on probes with red-shifted emission wavelength. In order to reach efficient quenching, i.e. fluorogenicity even in the red range of the spectrum, We present the synthesis, fluorogenic and conjugation characterization of bistetrazine-cyanine probes with emission maxima between 600-620 nm. The probes can bind to genetically altered proteins harboring an 11-amino acid peptide tag with two appending cyclooctyne motifs. Moreover, we also demonstrate the use of these bistetrazines as fluorogenic, covalent cross-linkers between monocyclooctynylated proteins. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Dynamic interactions between 14-3-3 proteins and phosphoproteins regulate diverse cellular processes
2004-01-01
14-3-3 proteins exert an extraordinarily widespread influence on cellular processes in all eukaryotes. They operate by binding to specific phosphorylated sites on diverse target proteins, thereby forcing conformational changes or influencing interactions between their targets and other molecules. In these ways, 14-3-3s ‘finish the job’ when phosphorylation alone lacks the power to drive changes in the activities of intracellular proteins. By interacting dynamically with phosphorylated proteins, 14-3-3s often trigger events that promote cell survival – in situations from preventing metabolic imbalances caused by sudden darkness in leaves to mammalian cell-survival responses to growth factors. Recent work linking specific 14-3-3 isoforms to genetic disorders and cancers, and the cellular effects of 14-3-3 agonists and antagonists, indicate that the cellular complement of 14-3-3 proteins may integrate the specificity and strength of signalling through to different cellular responses. PMID:15167810
Bastian, Brock; Zhang, Airong; Moffat, Kieren
2015-01-01
When people are morally convicted regarding a specific issue, these convictions exert a powerful influence on their attitudes and behavior. In the current research we examined whether there are boundary conditions to the influence of this effect. Specifically, whether in the context of salient economic rewards, moral convictions may become weaker predictors of attitudes regarding resource use. Focusing on the issue of mining we gathered large-scale samples across three different continents (Australia, Chile, and China). We found that moral convictions against mining were related to a reduced acceptance of mining in each country, while perceived economic rewards from mining increased acceptance. These two motivations interacted, however, such that when perceived economic benefit from mining was high, the influence of moral conviction was weaker. The results highlight the importance of understanding the roles of both moral conviction and financial gain in motivating attitudes towards resource use. PMID:26267904
New insights into the bioactivity of peptides from probiotics.
Mandal, Santi M; Pati, Bikas R; Chakraborty, Ranadhir; Franco, Octavio L
2016-06-01
Probiotics are unique bacteria that offer several therapeutic benefits to human beings when administered in optimum amounts. Probiotics are able to produce antimicrobial substances, which stimulate the body's immune responses. Here, we review in detail the anti-infective peptides derived from probiotics and their potential immunomodulatory and anti-inflammatory activities, including a major role in cross-talk between probiotics and gut microbiota under adverse conditions. Insights from the engineered cell surface of probiotics may provide novel anti-infective therapy by heterologous expression of receptor peptides of bacterial toxins. It may be possible to use antigenic peptides from viral pathogens as live vaccines. Another possibility is to generate antiviral peptides that bind directly to virus particles, while some peptides exert anti-inflammatory and anticancer effects. Some extracellular polymeric substances might serve as anti-infective peptides. These avenues of treatment have remained largely unexplored to date, despite their potential in generating powerful anti-inflammatory and anti-infective products.
Why do consumers respond to eco-labels? The case of Korea.
Hwang, Jung-Ah; Park, Youkyoung; Kim, Yeonbae
2016-01-01
Although eco-labels were introduced with the intention of encouraging eco-friendly purchasing behavior by consumers, they have had little effect on consumers' purchasing decisions, and therefore a significant gap exists between eco-label awareness and actual purchasing behavior. The aim of this study was to analyze consumer preference, in terms of public and private values, for two types of Korean eco-label that have been administered by the Korean government since 1992. Analyses were based on a structural equation model, employing the theory of reasoned action. Data were collected by survey. The results indicate that although general consumers are highly aware of the publicly valuable information that eco-labels provide, privately valuable information exerts far greater power over their purchasing intentions. Therefore, a supplementary policy that converts public value to private value could promote the purchase of eco-labeled products.
Doping in sport: effects, harm and misconceptions.
Birzniece, V
2015-03-01
Doping in sport is a widespread problem not just among elite athletes, but even more so in recreational sports. In scientific literature, major emphasis is placed on doping detection, whereas detrimental effects of doping agents on athletes' health are seldom discussed. Androgenic anabolic steroids are well known for their positive effects on muscle mass and strength. Human growth hormone also increases muscle mass, although the majority of that is an increase in extracellular fluid and not the functional muscle mass. In recreational athletes, growth hormone does not have major effect on muscle strength, power or aerobic capacity, but stimulates anaerobic exercise capacity. Erythropoietin administration increases oxygen-carrying capacity of blood improving endurance measures, whereas systemic administration of beta-adrenergic agonists may have positive effect on sprint capacity, and beta-adrenergic antagonists reduce muscle tremor. Thus, there are certain drugs that can improve selective aspects of physical performance. However, most of the doping agents exert serious side-effects, especially when used in combination, at high doses and for a long duration. The extent of long-term health consequences is difficult to predict, but likely to be substantial, especially when gene doping is considered. This review summarises the main groups of doping agents used by athletes, with the main focus on their effects on athletic performance and adverse effects. © 2014 Royal Australasian College of Physicians.
Panter, Abigail T.; Mouw, Mary S.; Amola, Kemi; Stein, Kathryn E.; Murphy, Joseph S.; Maiese, Eric M.; Wohl, David A.
2015-01-01
Abstract Among people living with HIV (PLWH), adherence to antiretroviral therapy (ART) is crucial for health, but patients face numerous challenges achieving sustained lifetime adherence. We conducted six focus groups with 56 PLWH regarding ART adherence barriers and collected sociodemographics and ART histories. Participants were recruited through clinics and AIDS service organizations in North Carolina. Dedoose software was used to support thematic analysis. Participants were 59% male, 77% black, aged 23–67 years, and living with HIV 4–20 years. Discussions reflected the fluid, complex nature of ART adherence. Maintaining adherence required participants to indefinitely assert consistent control across multiple areas including: their HIV disease, their own bodies, health care providers, and social systems (e.g., criminal justice, hospitals, drug assistance programs). Participants described limited control over treatment options, ART's impact on their body, and inconsistent access to ART and subsequent inability to take ART as prescribed. When participants felt they had more decision-making power, intentionally choosing whether and how to take ART was not exclusively a decision about best treating HIV. Instead, through these decisions, participants tried to regain some amount of power and control in their lives. Supportive provider relationships assuaged these struggles, while perceived side-effects and multiple co-morbidities further complicated adherence. Adherence interventions need to better convey adherence as a continuous, changing process, not a fixed state. A perspective shift among care providers could also help address negative consequences of the perceived power struggles and pressures that may drive patients to exert control via intentional medication taking practices. PMID:26505969
Muessig, Kathryn E; Panter, Abigail T; Mouw, Mary S; Amola, Kemi; Stein, Kathryn E; Murphy, Joseph S; Maiese, Eric M; Wohl, David A
2015-11-01
Among people living with HIV (PLWH), adherence to antiretroviral therapy (ART) is crucial for health, but patients face numerous challenges achieving sustained lifetime adherence. We conducted six focus groups with 56 PLWH regarding ART adherence barriers and collected sociodemographics and ART histories. Participants were recruited through clinics and AIDS service organizations in North Carolina. Dedoose software was used to support thematic analysis. Participants were 59% male, 77% black, aged 23-67 years, and living with HIV 4-20 years. Discussions reflected the fluid, complex nature of ART adherence. Maintaining adherence required participants to indefinitely assert consistent control across multiple areas including: their HIV disease, their own bodies, health care providers, and social systems (e.g., criminal justice, hospitals, drug assistance programs). Participants described limited control over treatment options, ART's impact on their body, and inconsistent access to ART and subsequent inability to take ART as prescribed. When participants felt they had more decision-making power, intentionally choosing whether and how to take ART was not exclusively a decision about best treating HIV. Instead, through these decisions, participants tried to regain some amount of power and control in their lives. Supportive provider relationships assuaged these struggles, while perceived side-effects and multiple co-morbidities further complicated adherence. Adherence interventions need to better convey adherence as a continuous, changing process, not a fixed state. A perspective shift among care providers could also help address negative consequences of the perceived power struggles and pressures that may drive patients to exert control via intentional medication taking practices.
Gasotransmitter Regulation of Ion Channels: A Key Step in O2 Sensing By the Carotid Body
Prabhakar, Nanduri R.
2014-01-01
Carotid bodies detect hypoxia in arterial blood, translating this stimulus into physiological responses via the CNS. It is long established that ion channels are critical to this process. More recent evidence indicates that gasotransmitters exert powerful influences on O2 sensing by the carotid body. Here, we review current understanding of hypoxia-dependent production of gasotransmitters, how they regulate ion channels in the carotid body, and how this impacts carotid body function. PMID:24382871
Issues in impedance selection and input devices for multijoint powered orthotics.
Lemay, M A; Hogan, N; van Dorsten, J W
1998-03-01
We investigated the applicability of impedance controllers to robotic orthoses for arm movements. We had tetraplegics turn a crank using their paralyzed arm propelled by a planar robot manipulandum. The robot was under impedance control, and chin motion served as command source. Stiffness varied between 50, 100, or 200 N/m and damping varied between 5 or 15 N/m/s. Results indicated that a low stiffness and high viscosity provided better directional control of the tangential force exerted on the crank.
2015-04-13
direction for apportionment of resources to deliver this national capability. The last time the UK introduced new aircraft carriers was at the height of...carefully in all but the most existential threats to a nation . Mahan believed that the blockade was the Navy’s greatest tactic in winning great wars. He...carriers at the heart of a comprehensive air, sea, and land capability to meet the national aims. But, in a severely resource constrained
Interest Group Conflict Over Medicaid Expansion: The Surprising Impact of Public Advocates
Callaghan, Timothy
2016-01-01
Objectives. We examined the potential economic, policy, and political influences on the decisions of the 50 US states to expand Medicaid under the Affordable Care Act. Methods. We related a measure of relative state progress toward Medicaid expansion updated to 2015 to each state’s economic circumstances, established policy frameworks in states, partisan control of state government, and lobbyists for businesses, medical professionals, unions, and public interest organizations. Results. The 9201 lobbyists working on health care reform in state capitols exerted a strong and significant impact on Medicaid expansion. Controlling for confounding factors (including partisanship and existing policy frameworks), we found that business and professional lobbyists exerted a negative effect on state Medicaid expansion and, unexpectedly, that public interest advocates exerted a positive effect. Conclusions. There are 3.1 million adults who lack coverage because they live in the 20 states that refused to expand Medicaid. Although political party and lobbyists for private interests present significant barriers in these states, legislative lobbying on behalf of the uninsured appears likely to be effective. PMID:26691109
White, Scott C; Hostler, David
2017-08-01
Fire suppression wearing thermal protective clothing (TPC) and self-contained breathing apparatus (SCBA) challenges a firefighter's balance and may explain firefighter falls. Postural control based on force plate centre of pressure (COP) was compared for healthy subjects wearing TPC and SCBA before and after 20 min of heavy physical exertion in hot conditions. Baseline measures with and without TPC and SCBA (two different SCBA cylinder masses) were compared before and after exertion that included elements of fire suppression activities in an environmental chamber. COP excursion and variability increased with exertion for TPC and SCBA conditions compared to non-stressed conditions. The two different cylinder masses had no significant effect. Wearing TPC and SCBA when physically stressed in a hot environment increases postural sway and exacerbates postural control. Subjects compensated for the extra mass and adjusted to control postural sway with the addition of TPC and SCBA, but the stress protocol amplified these adjustments. Practitioner Summary: Firefighters wear thermal protective clothing (TPC) and self-contained breathing apparatus (SCBA) when heat-stressed and fatigued. Wearing TPC and SCBA was found to negatively impact balance when stressed, but not for non-stressed or two different sized SCBA tanks. Simulating fire-ground conditions wearing TPC and SCBA should be considered for improving balance.
Veasey, Rachel C; Haskell-Ramsay, Crystal F; Kennedy, David O; Wishart, Karl; Maggini, Silvia; Fuchs, Caspar J; Stevenson, Emma J
2015-07-27
Exercise undertaken in a fasted state can lead to higher post-exercise mental fatigue. The administration of a vitamin and mineral complex with guaraná (MVM + G) has been shown to attenuate mental fatigue and improve performance during cognitively demanding tasks. This placebo-controlled, double-blind, randomized, balanced cross-over study examined the effect of MVM + G consumed prior to morning exercise on cognitive performance, affect, exertion, and substrate metabolism. Forty active males (age 21.4 ± 3.0 year; body mass index (BMI) 24.0 ± 2.4 kg/m2; maximal oxygen consumption (V̇O2max) 57.6 ± 7.3 mL/min/kg) completed two main trials, consuming either MVM + G or placebo prior to a 30-min run at 60% V̇O2max. Supplementation prior to exercise led to a small but significant reduction in Rating of Perceived Exertion (RPE) during exercise compared to the placebo. The MVM + G combination also led to significantly increased accuracy of numeric working memory and increased speed of picture recognition, compared to the placebo. There were no significant effects of supplementation on any other cognitive or mood measures or on substrate metabolism during exercise. These findings demonstrate that consuming a vitamin and mineral complex containing guaraná, prior to exercise, can positively impact subsequent memory performance and reduce perceived exertion during a moderate-intensity run in active males.
Veasey, Rachel C.; Haskell-Ramsay, Crystal F.; Kennedy, David O.; Wishart, Karl; Maggini, Silvia; Fuchs, Caspar J.; Stevenson, Emma J.
2015-01-01
Exercise undertaken in a fasted state can lead to higher post-exercise mental fatigue. The administration of a vitamin and mineral complex with guaraná (MVM + G) has been shown to attenuate mental fatigue and improve performance during cognitively demanding tasks. This placebo-controlled, double-blind, randomized, balanced cross-over study examined the effect of MVM + G consumed prior to morning exercise on cognitive performance, affect, exertion, and substrate metabolism. Forty active males (age 21.4 ± 3.0 year; body mass index (BMI) 24.0 ± 2.4 kg/m2; maximal oxygen consumption (V̇O2max) 57.6 ± 7.3 mL/min/kg) completed two main trials, consuming either MVM + G or placebo prior to a 30-min run at 60% V̇O2max. Supplementation prior to exercise led to a small but significant reduction in Rating of Perceived Exertion (RPE) during exercise compared to the placebo. The MVM + G combination also led to significantly increased accuracy of numeric working memory and increased speed of picture recognition, compared to the placebo. There were no significant effects of supplementation on any other cognitive or mood measures or on substrate metabolism during exercise. These findings demonstrate that consuming a vitamin and mineral complex containing guaraná, prior to exercise, can positively impact subsequent memory performance and reduce perceived exertion during a moderate-intensity run in active males. PMID:26225993
International society of sports nutrition position stand: caffeine and performance
2010-01-01
Position Statement: The position of The Society regarding caffeine supplementation and sport performance is summarized by the following seven points: 1.) Caffeine is effective for enhancing sport performance in trained athletes when consumed in low-to-moderate dosages (~3-6 mg/kg) and overall does not result in further enhancement in performance when consumed in higher dosages (≥ 9 mg/kg). 2.) Caffeine exerts a greater ergogenic effect when consumed in an anhydrous state as compared to coffee. 3.) It has been shown that caffeine can enhance vigilance during bouts of extended exhaustive exercise, as well as periods of sustained sleep deprivation. 4.) Caffeine is ergogenic for sustained maximal endurance exercise, and has been shown to be highly effective for time-trial performance. 5.) Caffeine supplementation is beneficial for high-intensity exercise, including team sports such as soccer and rugby, both of which are categorized by intermittent activity within a period of prolonged duration. 6.) The literature is equivocal when considering the effects of caffeine supplementation on strength-power performance, and additional research in this area is warranted. 7.) The scientific literature does not support caffeine-induced diuresis during exercise, or any harmful change in fluid balance that would negatively affect performance. PMID:20205813
Schubert, K; Shaikh, M B; Han, Y; Poherecky, L; Siegel, A
1996-08-01
Previous studies have shown that, at certain dose levels, ethanol can exert a powerful, facilitatory effect on aggressive behavior in both animals and humans. In the cat, however, it was discovered that ethanol differentially alters two forms of aggression that are common to this species. Defensive rage behavior is significantly enhanced, whereas predatory attack behavior is suppressed by ethanol administration. One possible mechanism governing alcohol's potentiation of defensive rage behavior is that it acts on the descending pathway from the medial hypothalamus to the midbrain periaqueductal gray (PAG)-an essential pathway for the expression of defensive rage behavior that uses excitatory amino acids as a neurotransmitter. This hypothesis is supported by the finding that the excitatory effects of alcohol on defensive rage behavior are blocked by administration of the N-methyl-D-aspartate antagonist alpha-2-amino-7-phosphoheptanoic acid (AP-7) when microinjected into the periaqueductal gray, a primary neuronal target of descending fibers from the medial hypothalamus that mediate the expression of defensive rage behavior. Thus, the present study establishes for the first time a specific component of the neural circuit for defensive rage behavior over which the potentiating effects of ethanol are mediated.
On the heating mechanism of magnetic flux loops in the solar atmosphere
NASA Technical Reports Server (NTRS)
Song, M. T.; Wu, S. T.
1984-01-01
An investigation is conducted of physical heating mechanisms due to the ponderomotive forces exerted by turbulent waves along the solar atmosphere's curved magnetic flux loops. Results indicate that the temperature difference between the inside and outside of the flux loop can be classified into three parts, two of which represent the cooling or heating effect exerted by the ponderomotive force, while the third is the heating effect due to turbulent energy conversion from the localized plasma. This heating mechanism is used to illustrate solar atmospheric heating by means of an example that leads to the formulation of plages.
Kuznetsov, B G
1978-11-01
The mineral water Essentuki 17 administered per so with glucose exerted a modifying effect on the regulation of glycaemia and insulinaemia in intact rats. This effect undergoes a few phases of changing and disappears by the 30th day. Under conditions of this adaptation, the glycaemia regulation is somewhat worsening. After i.v. administration of glucose during this period the regulation of glycaemia and insulinaemia remains unaltered. This suggests that the mineral water exerts its biological effect, mainly, on the entero-insular axis system (Unger and Eisentraut, 1969) and that the modifying effect is due not to a concrete complex of the mineral water electrolytes but rather to the unspecific factor of "perturbation" in the enteral medium.
Hellmann, Deborah F; Stiller, Anja; Glaubitz, Christoffer; Kliem, Sören
2018-03-01
Child maltreatment can severely impair children's emotional and physical well-being as well as their individual development across the life span. In 2011, the Criminological Research Institute of Lower Saxony (Germany), conducted a nationally representative victim survey on diverse forms of victimizations (N = 11,428). Among other things, experienced and exerted parental violence as well as participants' knowledge regarding the abolition of the parental right of corporal punishment were assessed. Apart from providing current estimates of the prevalence of experienced and exerted parental violence in Germany, we identified specific risk markers for the intergenerational transmission of parental violence. In summary, 52.6% of the participants reported experiences of at least one incident of at least minor parental violence until the age of 16 years, and 22.9% had exerted at least once at least one act of minor violence against their own children. Nonparametric conditional inference tree analyses revealed experienced parental violence as the most important risk marker for exerting parental violence. Furthermore, the number of children currently cared for, parental age, and origin as well as knowledge about the current legal situation regarding corporal punishment were significantly associated with exerting parental violence. For individuals without a history of parental violence, lack of experienced parental warmth and an age between 33 and 40 years increased the risk of exerting parental violence. The results are discussed in terms of their implications for designing effective prevention and intervention strategies. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Dong, Wenpeng; Zhang, Zhen; Liu, Zhengjun; Liu, Hao; Wang, Xianyue; Bi, Shenghui; Wang, Xiaowu; Ma, Tao; Zhang, Weida
2013-06-01
Intestinal ischemia/reperfusion (I/R) injury is considered to be associated with high morbidity and mortality rates. Osthole, a natural derivative of coumarin, has been shown to exert a variety of pharmacological and therapeutic effects under physiological and pathological conditions. In the present study, to investigate the protective effects of osthole against intestinal I/R injury, various doses of osthole (5, 10, 25 and 50 mg/kg) were pre-administered to mice subjected to intestinal I/R injury. A dose-dependent increase in the survival rate was observed in the osthole-treated mice. Pre-treatment with osthole (50 mg/kg) attenuated the destruction of epithelial cells within the villi induced by intestinal I/R injury, and suppressed oxidative stress, neutrophil infiltration and modulated nitric oxide (NO) levels. Moreover, the increased IκBα phosphorylation and nuclear factor (NF)-κB nuclear translocation induced by I/R injury were significantly decreased following pre-treatment with osthole. Taken together, our data demonstrate that osthole exerts protective effects against intestinal I/R injury in mice by suppressing oxidative stress, neutrophil infiltration and NO levels, partly through the inhibition of NF-κB nuclear translocation. Hence, the findings of the present study provide insight into the mechanisms through which osthole exerts its protective effects against intestinal I/R injury.
Psychological stress exerts an adjuvant effect on skin dendritic cell functions in vivo.
Saint-Mezard, Pierre; Chavagnac, Cyril; Bosset, Sophie; Ionescu, Marius; Peyron, Eric; Kaiserlian, Dominique; Nicolas, Jean-Francois; Bérard, Frédéric
2003-10-15
Psychological stress affects the pathophysiology of infectious, inflammatory, and autoimmune diseases. However, the mechanisms by which stress could modulate immune responses in vivo are poorly understood. In this study, we report that application of a psychological stress before immunization exerts an adjuvant effect on dendritic cell (DC), resulting in increased primary and memory Ag-specific T cell immune responses. Acute stress dramatically enhanced the skin delayed-type hypersensitivity reaction to haptens, which is mediated by CD8(+) CTLs. This effect was due to increased migration of skin DCs, resulting in augmented CD8(+) T cell priming in draining lymph nodes and enhanced recruitment of CD8(+) T cell effectors in the skin upon challenge. This adjuvant effect of stress was mediated by norepinephrine (NE), but not corticosteroids, as demonstrated by normalization of the skin delayed-type hypersensitivity reaction and DC migratory properties following selective depletion of NE. These results suggest that release of NE by sympathetic nerve termini during a psychological stress exerts an adjuvant effect on DC by promoting enhanced migration to lymph nodes, resulting in increased Ag-specific T cell responses. Our findings may open new ways in the treatment of inflammatory diseases, e.g., psoriasis, allergic contact dermatitis, and atopic dermatitis.
Curcumin Attenuates Amyloid-β Aggregate Toxicity and Modulates Amyloid-β Aggregation Pathway.
Thapa, Arjun; Jett, Stephen D; Chi, Eva Y
2016-01-20
The abnormal misfolding and aggregation of amyloid-β (Aβ) peptides into β-sheet enriched insoluble deposits initiates a cascade of events leading to pathological processes and culminating in cognitive decline in Alzheimer's disease (AD). In particular, soluble oligomeric/prefibrillar Aβ have been shown to be potent neurotoxins. The naturally occurring polyphenol curcumin has been shown to exert a neuroprotective effect against age-related neurodegenerative diseases such as AD. However, its protective mechanism remains unclear. In this study, we investigated the effects of curcumin on the aggregation of Aβ40 as well as Aβ40 aggregate induced neurotoxicity. Our results show that the curcumin does not inhibit Aβ fibril formation, but rather enriches the population of "off-pathway" soluble oligomers and prefibrillar aggregates that were nontoxic. Curcumin also exerted a nonspecific neuroprotective effect, reducing toxicities induced by a range of Aβ conformers, including monomeric, oligomeric, prefibrillar, and fibrillar Aβ. The neuroprotective effect is possibly membrane-mediated, as curcumin reduced the extent of cell membrane permeabilization induced by Aβ aggregates. Taken together, our study shows that curcumin exerts its neuroprotective effect against Aβ induced toxicity through at least two concerted pathways, modifying the Aβ aggregation pathway toward the formation of nontoxic aggregates and ameliorating Aβ-induced toxicity possibly through a nonspecific pathway.
Cao, Changfu; Su, Meiqing; Zhou, Feng
2017-08-01
A growing body of evidence suggests that inflammation may contribute toward the development of major depressive disorder. Mangiferin, a glucosylxanthone from Mangifera indica, exerts a number of biological actions, including anti-inflammatory effects. Although mangiferin has potential antidepressant activity, the mechanisms of this effect remain unclear. The present study investigated the effects of mangiferin on behavioral changes and inflammatory responses induced by chronic mild stress (CMS) in mice. We found that treatment with mangiferin for 3 weeks significantly increased the body weight of mice and ameliorated CMS-induced behavioral abnormalities by increasing sucrose consumption, improving locomotor activities, and decreasing the immobility time in the forced-swimming test and tail-suspension test. It also suppressed increased serum corticosterone levels in CMS mice. In response to CMS induction, the NLR family, pyrin domain containing 3 (NLRP3) inflammasome was activated and interleukin (IL)-1β and IL-18 levels were increased in the mouse hippocampus. Mangiferin treatment downregulated the expression of NLRP3, the adaptor protein ASC, and caspase-1, which subsequently reduced the production of IL-1β and IL-18 in CMS mice. In sum, our results indicate that mangiferin exerts antidepressant-like effects in CMS model, possibly by inhibiting IL-1β production and NLRP3 inflammasome expression.
Mega-dose vitamin C attenuated lung inflammation in mouse asthma model.
Jeong, Young-Joo; Kim, Jin-Hee; Kang, Jae Seung; Lee, Wang Jae; Hwang, Young-Il
2010-12-01
Asthma is a Th2-dependent disease mediated by IgE and Th2 cytokines, and asthmatic patients suffer from oxidative stresses from abnormal airway inflammation. Vitamin C is a micro-nutrient functioning as an antioxidant. When administered at a mega-dose, vitamin C has been reported to shift immune responses toward Th1. Thus, we tried to determine whether vitamin C exerted beneficial effects in asthma animal model. Asthma was induced in mice by sensitizing and challenging with ovalbumin. At the time of challenge, 3~5 mg of vitamin C was administered and the effects were evaluated. Vitamin C did not modulate Th1/Th2 balance in asthma model. However, it decreased airway hyperreactivity to methacholine, decreased inflammatory cell numbers in brochoalveolar lavage fluid, and moderate reduction of perivascular and peribronchiolar inflammatory cell infiltration. These results suggest that vitamin C administered at the time of antigen challenge exerted anti-inflammatory effects. Further studies based on chronic asthma model are needed to evaluate a long-term effect of vitamin C in asthma. In conclusion, even though vitamin C did not show any Th1/Th2 shifting effects in this experiment, it still exerted moderate anti-inflammatory effects. Considering other beneficial effects and inexpensiveness of vitamin C, mega-dose usage of vitamin C could be a potential supplementary modality for the management of asthma.
Sakata, Chinatsu; Suzuki, Ken-Ichi; Morita, Yoshiaki; Kawasaki, Tomihisa
2017-03-05
Clopidogrel (Plavix ® , Sanofi-Aventis), the adenosine diphosphate P2Y 12 receptor antagonist, is reported to be effective in the prevention of cardiovascular events and is often used in combination with aspirin, particularly in high-risk patients. ASP6537 is a reversible cyclooxygenase (COX)-1 inhibitor that is under investigation as an anti-platelet agent. First, we investigated the reversibility of the antiplatelet effect of ASP6537 and its interaction with ibuprofen to compare the usability of ASP6537 with that of aspirin. We then evaluated the antithrombotic effect of ASP6537 in combination with clopidogrel using a FeCl 3 -induced thrombosis model in guinea pigs. ASP6537 exerted reversible antiplatelet activity, and no pharmacodynamic interaction with ibuprofen was noted. When administered as monotherapy, ASP6537 exerted a significant antithrombotic effect at ≥3mg/kg, while aspirin inhibited thrombosis at 100mg/kg. ASP6537 exerted significant additive effects in combination with clopidogrel, and the minimum antithrombotic dose was reduced by concomitant administration of clopidogrel. Our study showed that ASP6537 did not interact with ibuprofen and has clear additive effects in combination with clopidogrel. ASP6537 may therefore represent a promising antiplatelet agent for use in clinical settings in combination with clopidogrel. Copyright © 2017 Elsevier B.V. All rights reserved.
Dallago, Francesca; Mirisola, Alberto; Roccato, Michele
2012-01-01
In an Italian sample (N = 483, 78.23% women, mean age = 27.61 years old), we used structural equation modeling with latent variables and interactions to analyze the direct, indirect, and interactive effects exerted on right-wing authoritarianism by the Big Five factors of personality and by dangerous world beliefs. Openness, Neuroticism, and Conscientiousness exerted direct effects on right-wing authoritarianism; the first two relationships were partially mediated by dangerous world beliefs. Most importantly, the relationship between dangerous world beliefs and right-wing authoritarianism was moderated by Openness: dangerous world beliefs significantly influenced right-wing authoritarianism solely for participants high in Openness. Limitations and possible developments of this research are discussed.
Wang, Mei-Chuan; Joel Wong, Y; Tran, Kimberly K; Nyutu, Pius N; Spears, Angela
2013-01-01
This study utilized an ecological framework to explore the role of 4 culturally relevant protective factors-reasons for living, Afrocentric worldview, family support, and friend support-in protecting Black American college students from suicidal behavior. Participants were 289 Black American college students. We hypothesized that these 4 culturally relevant factors would exert indirect protective effects on suicidal behavior through their association with reduced depressive symptoms. Results indicated that reasons for living, perceived supportive behaviors from family, and Afrocentric worldview exerted indirect protective effects on suicidal behaviors through their negative associations with depressive symptoms. The mediation effect from friend support to depression and suicidal behavior was not significant.
Luine, Victoria N.; Frankfurt, Maya
2012-01-01
Estrogens exert sustained, genomically mediated effects on memory throughout the female life cycle, but here we review new studies documenting rapid effects of estradiol on memory, which are exerted through membrane-mediated mechanisms. Use of recognition memory tasks in rats, shows that estrogens enhance memory consolidation within one hour. 17α-estradiol is more potent than 17β-estradiol, and the dose response relationship between estrogens and memory is an inverted U shape. Use of specific estrogen receptor (ER) agonists suggests mediation by an ERβ-like membrane receptor. Enhanced memory is associated with increased spine density and altered noradrenergic activity in the medial prefrontal cortex and hippocampus within 30 min. of administration. The environmental chemical, bisphenol-A, rapidly antagonizes enhancements in memory in both sexes possibly through actions on spines. Thus, estradiol and related compounds exert rapid alterations in cognition through non-genomic mechanisms, a finding which may provide a basis for better understanding and treating memory impairments. PMID:22981654
Field-Based Pre-Cooling for On-Court Tennis Conditioning Training in the Heat
Duffield, Rob; Bird, Stephen P.; Ballard, Robert J.
2011-01-01
The present study investigated the effects of pre-cooling for on- court, tennis-specific conditioning training in the heat. Eight highly-trained tennis players performed two on-court conditioning sessions in 35°C, 55% Relative Humidity. Sessions were randomised, involved either a pre-cooling or control session, and consisted of 30-min of court- based, tennis movement drills. Pre-cooling involved 20-min of an ice-vest and cold towels to the head/neck and legs, followed by warm-up in a cold compression garment. On-court movement distance was recorded by 1Hz Global Positioning Satellite (GPS) devices, while core temperature, heart rate and perceptual exertion and thermal stress were also recorded throughout the session. Additionally, mass and lower-body peak power during repeated counter-movement jumps were measured before and after each session. No significant performance differences were evident between conditions, although a moderate-large effect (d = 0.7-1.0; p > 0.05) was evident for total (2989 ± 256 v 2870 ± 159m) and high-intensity (805 ± 340 v 629 ± 265m) distance covered following pre-cooling. Further, no significant differences were evident between conditions for rise in core temperature (1.9 ± 0.4 v 2. 2 ± 0.4°C; d > 0.9; p > 0.05), although a significantly smaller change in mass (0.9 ± 0.3 v 1. 3 ± 0.3kg; p < 0.05) was present following pre-cooling. Perceived thermal stress and exertion were significantly lower (d > 1.0; p < 0.05) during the cooling session. Finally, lower-body peak power did not differ between conditions before or after training (d < 0.3; p > 0.05). Conclusions: Despite trends for lowered physiological load and increased distances covered following cooling, the observed responses were not significantly different or as explicit as previously reported laboratory-based pre-cooling research. Key points Pre-cooling did not significantly enhance training performance or reduce physiological load for tennis training in the heat, although trends indicate some benefits for both. Pre-cooling can reduce perceptual strain of on-court tennis training in the heat to improve perceptual load of training sessions. Court-side pre-cooling may not be of sufficient volume to invoke large physiological changes. PMID:24149886
Tunón, H; Thorsell, W; Mikiver, A; Malander, I
2006-06-01
A toluene extract of southernwood (Artemisia abrotanum) and the essential oil from flowers of carnation (Dianthus caryophyllum ) exerted pronounced a repellent effect both against ticks (nymphs of Ixodes ricinus) and yellow fever mosquitoes (Aedes aegypti). The most potent repellents found were coumarin and thujyl alcohol from A. abrotanum and phenylethanol from D. caryophyllum where coumarin and thujyl alcohol were also detected.
Savini, Giacomo; Næser, Kristian
2015-01-13
To investigate the influence of posterior corneal astigmatism, surgically-induced corneal astigmatism (SICA), intraocular lens (IOL) orientation, and effective lens position on the refractive outcome of toric IOLs. Five models were prospectively investigated. Keratometric astigmatism and an intended SICA of 0.2 diopters (D) were entered into model 1. Total corneal astigmatism, measured by a rotating Scheimpflug camera, was used instead of keratometric astigmatism in model 2. The mean postoperative SICA, the actual postoperative IOL orientation, and the influence of the effective lens position were added, respectively, into models 3, 4, and 5. Astigmatic data were vectorially described by meridional and torsional powers. A set of equations was developed to describe the error in refractive astigmatism (ERA) as the difference between the postoperative refractive astigmatism and the target refractive astigmatism. We enrolled 40 consecutive eyes. In model 1, ERA calculations revealed significant cylinder overcorrection in with-the-rule (WTR) eyes (meridional power = -0.59 ± 0.34 D, P < 0.0001) and undercorrection in against-the-rule (ATR) eyes (0.32 ± 0.42 D, P = 0.01). When total corneal astigmatism was used instead of keratometric astigmatism (model 2), the ERA meridional power decreased in WTR (-0.13 ± 0.42 D) and ATR (0.07 ± 0.59 D) eyes, both values being not statistically significant. Models 3 to 5 did not lead to significant improvement. Posterior corneal astigmatism exerts the highest influence on the ERA after toric IOL implantation. Basing calculations on total corneal astigmatism rather than keratometric astigmatism improves the prediction of the residual refractive astigmatism. Copyright 2015 The Association for Research in Vision and Ophthalmology, Inc.
Post-exertion neurocognitive test failure among student-athletes following concussion.
McGrath, Neal; Dinn, Wayne M; Collins, Michael W; Lovell, Mark R; Elbin, R J; Kontos, Anthony P
2013-01-01
The purpose of the present study was to examine post-exertion (PE) neurocognitive performance among student-athletes following concussion who were asymptomatic and returned to baseline normal neurocognitive test levels at rest. This study examined the neurocognitive performance of a sub-set of student-athletes who 'failed' to perform at baseline levels of neurocognitive function, i.e. exhibited downward reliable change index (RCI) alterations following a moderate exertional protocol during recovery from concussion. A retrospective records review was carried out of Immediate Post-concussion Assessment and Cognitive Testing (ImPACT) and neuropsychological consultation data among athletes with sports-related concussion from a network of 22 schools and one junior hockey programme. Fifty-four student-athletes met inclusion criteria and participated in the study. A total of 27.7% of concussed student-athletes who were symptom-free and returned to baseline on ImPACT at rest (i.e. no longer demonstrated performance deficits on neurocognitive tests) exhibited cognitive decline following moderate physical exertion. The PE cognitive changes were not simply general performance effects, but significant changes in memory ability in the presence of intact processing speed functions. The PE-Pass and PE-Fail groups did not, however, differ on post-concussive symptoms or concussion history. Clinicians' return-to-play evaluation protocols should include post-exertional computerized neurocognitive testing.
Higher motivation - greater control? The effect of arousal on judgement.
Riemer, Hila; Viswanathan, Madhu
2013-01-01
This research examines control over the effect of arousal, a dimension of affect, on judgement. Past research shows that high processing motivation enhances control over the effects of affect on judgement. Isolating and studying arousal as opposed to valence, the other dimension of affect, and its effect on judgement, we identify boundary conditions for past findings. Drawing from the literature on processes by which arousal influences judgement, we demonstrate that the role of motivation is contingent upon the type of judgement task (i.e., memory- versus stimulus-based judgement). In stimulus-based judgement, individuals exert greater control over the effect of arousal on judgement under low compared to high motivation. In contrast, in memory-based judgement individuals exert greater control over the effect of arousal under high compared to low motivation. Theoretical implications and avenues for future research are discussed.
Yoshino, Hironori; Iwabuchi, Miyu; Kazama, Yuka; Furukawa, Maho; Kashiwakura, Ikuo
2018-04-01
Retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs) are pattern-recognition receptors that recognize pathogen-associated molecular patterns and induce antiviral immune responses. Recent studies have demonstrated that RLR activation induces antitumor immunity and cytotoxicity against different types of cancer, including lung cancer. However a previous report has demonstrated that ionizing radiation exerts a limited effect on RLR in human monocytic cell-derived macrophages, suggesting that RLR agonists may be used as effective immunostimulants during radiation therapy. However, it is unclear whether ionizing radiation affects the cytotoxicity of RLR agonists against cancer cells. Therefore, in the present study the effects of cotreatment with ionizing radiation and RLR agonists on cytotoxicity against human non-small cell lung cancer cells A549 and H1299 was investigated. Treatment with RLR agonist poly(I:C)/LyoVec™ [poly(I:C)] exerted cytotoxic effects against human non-small cell lung cancer. The cytotoxic effects of poly(I:C) were enhanced by cotreatment with ionizing radiation, and poly(I:C) pretreatment resulted in the radiosensitization of non-small cell lung cancer. Furthermore, cotreatment of A549 and H1299 cells with poly(I:C) and ionizing radiation effectively induced apoptosis in a caspase-dependent manner compared with treatment with poly(I:C) or ionizing radiation alone. These results indicate that RLR agonists and ionizing radiation cotreatment effectively exert cytotoxic effects against human non-small cell lung cancer through caspase-mediated apoptosis.
Shirayama, Yukihiko; Muneoka, Katsumasa; Fukumoto, Makoto; Tadokoro, Shigenori; Fukami, Goro; Hashimoto, Kenji; Iyo, Masaomi
2011-10-01
Patients with depression showed a decrease in plasma and cerebrospinal fluid allopregnanolone (ALLO). But antidepressants increased the contents of ALLO in the rat brain. We examined the antidepressant-like effects of infusion of ALLO into the cerebral ventricle, hippocampus, amygdala, nucleus accumbens, or prefrontal cortex of learned helplessness (LH) rats (an animal model of depression). Of these regions, infusions of ALLO into the cerebral ventricle, the CA3 region of hippocampus, or the central region of amygdala exerted antidepressant-like effects. Infusion of ALLO into the hippocampal CA3 region or the central amygdala did not produce memory deficits or locomotor activation in the passive avoidance and open field tests. It is well documented that ALLO exerts its effects through GABA receptors. Therefore, we examined the antagonistic effects of flumazenil (a GABA receptor antagonist) on the antidepressant-like effects of ALLO. Coinfusion of flumazenil with ALLO into the hippocampal CA3 region, but not into the central amygdala, blocked the antidepressant-like effects of ALLO. However, coinfusion of (+)MK801 (an NMDA receptor antagonist), but not cycloheximide (a protein synthesis inhibitor), blocked the antidepressant-like effects of ALLO in the central amygdala. These results suggest that ALLO exerts antidepressant-like effects in the CA3 region of hippocampus through the GABA system and in the central region of amygdala, dependently on the activation of the glutamatergic mechanisms. Copyright © 2010 Wiley-Liss, Inc.
Koushki, Davood; Latifi, Sahar; Norouzi Javidan, Abbas; Matin, Marzieh
2015-01-01
Context Inflammation after spinal cord injury (SCI) may be responsible for further neural damages and therefore inhibition of inflammatory processes may exert a neuroprotection effect. Objectives To assess the efficacy of some non-conventional herbal medications including sulforaphane, tanshinone IIA, and tetramethylpyrazine in reducing inflammation and compare them with a known effective anti-inflammatory agent (interleukin-10 (IL-10)). Methods We searched relevant articles in Ovid database, Medline (PubMed) EMBASE, Google Scholar, Cochrane, and Scopus up to June 2013. The efficacy of each treatment and study powers were compared using random effects model of meta-analysis. To our knowledge, no conflict of interest exists. Results Eighteen articles entered into the study. The meta-analysis revealed that exogenous IL-10 was more effective in comparison with the mentioned herbal extracts. The proposed pathways for each medication's effect on reducing the inflammation process are complex and many overlaps may exist. Conclusion IL-10 has a strong effect in the induction of neuroprotection and neurorecovery after SCI by multiple pathways. Tetramethylpyrazine has an acceptable influence in reducing inflammation through the up-regulation of IL-10. Outcomes of sulforaphane and tanshinone IIA administration are acceptable but still weaker than IL-10. PMID:24969510
Koushki, Davood; Latifi, Sahar; Norouzi Javidan, Abbas; Matin, Marzieh
2015-01-01
Inflammation after spinal cord injury (SCI) may be responsible for further neural damages and therefore inhibition of inflammatory processes may exert a neuroprotection effect. To assess the efficacy of some non-conventional herbal medications including sulforaphane, tanshinone IIA, and tetramethylpyrazine in reducing inflammation and compare them with a known effective anti-inflammatory agent (interleukin-10 (IL-10)). We searched relevant articles in Ovid database, Medline (PubMed) EMBASE, Google Scholar, Cochrane, and Scopus up to June 2013. The efficacy of each treatment and study powers were compared using random effects model of meta-analysis. To our knowledge, no conflict of interest exists. Eighteen articles entered into the study. The meta-analysis revealed that exogenous IL-10 was more effective in comparison with the mentioned herbal extracts. The proposed pathways for each medication's effect on reducing the inflammation process are complex and many overlaps may exist. IL-10 has a strong effect in the induction of neuroprotection and neurorecovery after SCI by multiple pathways. Tetramethylpyrazine has an acceptable influence in reducing inflammation through the up-regulation of IL-10. Outcomes of sulforaphane and tanshinone IIA administration are acceptable but still weaker than IL-10.
Magri, María Laura; Gottardo, María Florencia; Zárate, Sandra; Eijo, Guadalupe; Ferraris, Jimena; Jaita, Gabriela; Ayala, Mariela Moreno; Candolfi, Marianela; Pisera, Daniel; Seilicovich, Adriana
2016-03-01
Hormones locally synthesized in the anterior pituitary gland are involved in regulation of pituitary cell renewal. In the pituitary, testosterone (T) may exert its actions per se or by conversion to dihydrotestosterone (DHT) or 17β-estradiol (E2) by 5α-reductase and aromatase activity, which are expressed in this gland. Previous reports from our laboratory showed that estrogens modulate apoptosis of lactotropes and somatotropes from female rats. Now, we examined the in vitro and in vivo effects of gonadal steroids on apoptosis of anterior pituitary cells from adult male rats. T in vitro did not modify apoptosis in anterior pituitary cells from gonadectomized (GNX) male rats. DHT, a non-aromatizable androgen, exerted direct antiapoptotic action on total anterior pituitary cells and folliculo-stellate cells, but not on lactotropes, somatotropes, or gonadotropes. On the contrary, E2 exerted a rapid apoptotic effect on total cells as well as on lactotropes and somatotropes. Incubation of anterior pituitary cells with T in presence of Finasteride, an inhibitor of 5α-reductase, increased the percentage of TUNEL-positive cells. In vivo administration of DHT to GNX rats reduced apoptosis in the anterior pituitary whereas E2 exerted proapoptotic action and reduced cells in G2/M-phase of the cell cycle. In summary, our results indicate that DHT and E2 have opposite effects on apoptosis in the anterior pituitary gland suggesting that local metabolization of T to these steroids could be involved in pituitary cell turnover in males. Changes in expression and/or activity of 5α-reductase and aromatase may play a role in the development of anterior pituitary tumors.
Miyaguchi, Kazuyoshi; Demura, Shinichi
2006-05-01
The purpose of this study was to examine the output properties of muscle power by the dominant upper limb using SSC, and the relationships between the power output by SSC and a one-repetition maximum bench press (1 RM BP) used as a strength indicator of the upper body. Sixteen male athletes (21.4+/-0.9 yr) participated in this study. They pulled a load of 40% of maximum voluntary contraction (MVC) at a stretch by elbow flexion of the dominant upper limb in the following three preliminary conditions: static relaxed muscle state (SR condition), isometric muscle contraction state (ISO condition), and using SSC (SSC condition). The velocity with a wire load via a pulley during elbow flexion was measured accurately using a power instrument with a rotary encoder, and the muscle power curve was drawn from the product of the velocity and load. Significant differences were found among all evaluation parameters of muscle power exerted from the above three conditions and the parameters regarding early power output during concentric contraction were larger in the SSC condition than the SR and ISO conditions. The parameters on initial muscle contraction velocity when only using SSC significantly correlated with 1 RM BP (r=0.60-0.62). The use of SSC before powerful elbow flexion may contribute largely to early explosive power output during concentric contraction. Bench press capacity relates to a development of the above early power output when using SSC.
The power of relativistic jets is larger than the luminosity of their accretion disks.
Ghisellini, G; Tavecchio, F; Maraschi, L; Celotti, A; Sbarrato, T
2014-11-20
Theoretical models for the production of relativistic jets from active galactic nuclei predict that jet power arises from the spin and mass of the central supermassive black hole, as well as from the magnetic field near the event horizon. The physical mechanism underlying the contribution from the magnetic field is the torque exerted on the rotating black hole by the field amplified by the accreting material. If the squared magnetic field is proportional to the accretion rate, then there will be a correlation between jet power and accretion luminosity. There is evidence for such a correlation, but inadequate knowledge of the accretion luminosity of the limited and inhomogeneous samples used prevented a firm conclusion. Here we report an analysis of archival observations of a sample of blazars (quasars whose jets point towards Earth) that overcomes previous limitations. We find a clear correlation between jet power, as measured through the γ-ray luminosity, and accretion luminosity, as measured by the broad emission lines, with the jet power dominating the disk luminosity, in agreement with numerical simulations. This implies that the magnetic field threading the black hole horizon reaches the maximum value sustainable by the accreting matter.
Transient boiling in two-phase helium natural circulation loops
NASA Astrophysics Data System (ADS)
Furci, H.; Baudouy, B.; Four, A.; Meuris, C.
2014-01-01
Two-phase helium natural circulation loops are used for cooling large superconducting magnets, as CMS for LHC. During normal operation or in the case of incidents, transients are exerted on the cooling system. Here a cooling system of this type is studied experimentally. Sudden power changes are operated on a vertical-heated-section natural convection loop, simulating a fast increase of heat deposition on magnet cooling pipes. Mass flow rate, heated section wall temperature and pressure drop variations are measured as a function of time, to assess the time behavior concerning the boiling regime according to the values of power injected on the heated section. The boiling curves and critical heat flux (CHF) values have been obtained in steady state. Temperature evolution has been observed in order to explore the operating ranges where heat transfer is deteriorated. Premature film boiling has been observed during transients on the heated section in some power ranges, even at appreciably lower values than the CHF. A way of attenuating these undesired temperature excursions has been identified through the application of high enough initial heating power.
Skafte, Ina; Silberschmidt, Margrethe
2014-01-01
The gender-based response to HIV in sub-Saharan Africa has tended to reinforce normative stereotypes of women as subordinated, passive and powerless victims, in particular in sexual relations. However, based on qualitative data from Rwanda, this paper argues that such conceptualisations fail to recognise that while women do comply with prevalent social norms, they also challenge these norms and sex becomes a domain in which they can exert power. Female sexuality and sexual gratification - acknowledged and valued by women as well as men - play a pivotal role in the Rwandese mode of sexual intercourse. This provides women a central position in sexual relations, which affords them sexual power. Recognising their sexuality as a resource and drawing upon this 'sexual capital', women are active social agents who have the capacity to manipulate and challenge male dominance in a deliberate strategy both to practice safer sex and to access decision-making power and material resources. This suggests that inherent in sexual relations is a potential for the empowerment of women and the transformation of gender relations.
Functional anatomy of gliding membrane muscles in the sugar glider (Petaurus breviceps).
Endo, H; Yokokawa, K; Kurohmaru, M; Hayashi, Y
1998-02-01
In order to clarify the morphological adaptation for gliding behavior in the marsupial mammals, the gliding membrane muscles in the sugar glider (Petaurus breviceps) were observed. Unlike the styliform cartilage in flying squirrels, the sugar glider has a well-developed tibiocarpalis muscle in the most lateral area of the gliding membrane. The gliding membrane substantially consists of the humerodorsalis and tibioabdominalis muscle complex. We believe that the thick tibiocarpalis bundle and the humerodorsalis and tibioabdominalis muscle complex may serve as a membrane controller in the gliding behavior. A characteristic thin membranous structure between the cutaneous and deeper muscles was observed. In addition to the direct powerful control exerted by trunk and limb movement, we suggest that indirect power conduction by this thin membranous structure may contribute to gliding membrane control.
Werling, Dora; Banks, William A.; Salameh, Therese S.; Kvarik, Timea; Kovacs, Laszlo Akos; Vaczy, Alexandra; Szabo, Edina; Mayer, Flora; Varga, Rita; Tamas, Andrea; Toth, Gabor; Biro, Zsolt; Atlasz, Tamas; Reglodi, Dora
2017-01-01
The neuropeptide pituitary adenylate cyclase activating polypeptide (PACAP) has two active forms, PACAP1-27 and PACAP1-38. Among the well-established actions are PACAP’s neurotrophic and neuroprotective effects, which have also been proven in models of different retinopathies. The route of delivery is usually intravitreal in studies proving PACAP’s retinoprotective effects. Recently, we have shown that PACAP1-27 delivered as eye drops in benzalkonium-chloride was able to cross the ocular barriers and exert retinoprotection in ischemia. Since PACAP1-38 is the dominant form of the naturally occurring PACAP, our aim was to investigate whether the longer form is also able to cross the barriers and exert protective effects in permanent bilateral common carotid artery occlusion (BCCAO), a model of retinal hypoperfusion. Our results show that radioactive PACAP1-38 eye drops could effectively pass through the ocular barriers to reach the retina. Routine histological analysis and immunohistochemical evaluation of the Müller glial cells revealed that PACAP1-38 exerted retinoprotective effects. PACAP1-38 attenuated the damage caused by hypoperfusion, apparent in almost all retinal layers, and it decreased the glial cell overactivation. Overall, our results confirm that PACAP1-38 given in the form of eye drops is a novel protective therapeutic approach to treat retinal diseases. PMID:28335564
de Quadros, Ana Paula Oliveira; Mazzeo, Dania Elisa Christofoletti; Marin-Morales, Maria Aparecida; Perazzo, Fábio Ferreira; Rosa, Paulo Cesar Pires; Maistro, Edson Luis
2017-01-01
Crataegus oxyacantha, a plant of the Rosaceae family also known "English hawthorn, haw, maybush, or whitethorn," has long been used for medicinal purposes such as digestive disorders, hyperlipidemia, dyspnea, inducing diuresis, and preventing kidney stones. However, the predominant use of this plant has been to treat cardiovascular disorders. Due to a lack of studies on the genotoxicity of C. oxyacantha, this investigation was undertaken to determine whether its fruit extract exerts cytotoxic, genotoxic, or clastogenic/aneugenic effects in leukocytes and HepG2 (liver hepatocellular carcinoma) cultured human cells, or mutagenic effects in TA100 and TA98 strains of Salmonella typhimurium bacterium. Genotoxicity analysis showed that the extract produced no marked genotoxic effects at concentrations of 2.5 or 5 µg/ml in either cell type; however, at concentrations of 10 µg/ml or higher significant DNA damage was detected. The micronucleus test also demonstrated that concentrations of 10 µg/ml or higher produced clastogenic/aneugenic responses. In the Ames test, the extract induced mutagenic effects in TA98 strain of S. typhimurium with metabolic activation at all tested concentrations (2.5 to 500 µg/ml). Data indicate that, under certain experimental conditions, the fruit extract of C. oxyacantha exerts genotoxic and clastogenic/aneugenic effects in cultured human cells, and with metabolism mutagenicity occurs in bacteria cells.
Shirayama, Yukihiko; Yang, Chun; Zhang, Ji-chun; Ren, Qian; Yao, Wei; Hashimoto, Kenji
2015-12-01
Role of brain-derived neurotrophic factor (BDNF)-TrkB signaling in a learned helplessness (LH) model of depression was investigated. LH rats showed a reduction of BDNF in the medial prefrontal cortex (mPFC), CA3, and dentate gyrus (DG) of the hippocampus, whereas LH rats showed an increase in BDNF in the nucleus accumbens (NAc). Furthermore, levels of proBDNF, a BDNF precursor, were higher in the mPFC, but lower in the NAc, of LH rats. A single bilateral infusion of a TrkB agonist 7,8-DHF, but not a TrkB antagonist ANA-12, into the infralimbic (IL) of mPFC, DG, and CA3, but not the prelimbic (PrL) of mPFC, exerted antidepressant effects in LH rats. In contrast, a single bilateral infusion of ANA-12, but not 7,8-DHF, into the core and shell of NAc exerted antidepressant-like effects in LH rats, with more potent effects observed for the NAc core than for NAc shell. Interestingly, a single administration of 7,8-DHF (10mg/kg, i.p.) significantly improved a decreased phosphorylation of TrkB in the mPFC, CA3, and DG of LH rats. Additionally, ANA-12 (0.5mg/kg, i.p.) significantly improved an increased phosphorylation of TrkB in the NAc of LH rats. In conclusion, these results suggest that LH causes depression-like behavior by altering BDNF in the brain regions, and that proBDNF-BDNF processing and transport may be altered in the mPFC-NAc circuit of LH rats. Therefore, TrkB agonists might exert antidepressant effects by stimulating TrkB in the IL, CA3, and DG, while TrkB antagonists might exert antidepressant effects by blocking TrkB in the NAc. Copyright © 2015 Elsevier B.V. and ECNP. All rights reserved.
Kepinska, Olga; Pereda, Ernesto; Caspers, Johanneke; Schiller, Niels O
2017-12-01
The goal of the present study was to investigate the initial phases of novel grammar learning on a neural level, concentrating on mechanisms responsible for individual variability between learners. Two groups of participants, one with high and one with average language analytical abilities, performed an Artificial Grammar Learning (AGL) task consisting of learning and test phases. During the task, EEG signals from 32 cap-mounted electrodes were recorded and epochs corresponding to the learning phases were analysed. We investigated spectral power modulations over time, and functional connectivity patterns by means of a bivariate, frequency-specific index of phase synchronization termed Phase Locking Value (PLV). Behavioural data showed learning effects in both groups, with a steeper learning curve and higher ultimate attainment for the highly skilled learners. Moreover, we established that cortical connectivity patterns and profiles of spectral power modulations over time differentiated L2 learners with various levels of language analytical abilities. Over the course of the task, the learning process seemed to be driven by whole-brain functional connectivity between neuronal assemblies achieved by means of communication in the beta band frequency. On a shorter time-scale, increasing proficiency on the AGL task appeared to be supported by stronger local synchronisation within the right hemisphere regions. Finally, we observed that the highly skilled learners might have exerted less mental effort, or reduced attention for the task at hand once the learning was achieved, as evidenced by the higher alpha band power. Copyright © 2017 Elsevier Inc. All rights reserved.
Potential behavioral and pro-oxidant effects of Petiveria alliacea L. extract in adult rats.
de Andrade, Thaís Montenegro; de Melo, Ademar Soares; Dias, Rui Guilherme Cardoso; Varela, Everton Luís Pompeu; de Oliveira, Fábio Rodrigues; Vieira, José Luís Fernandes; de Andrade, Marcieni Ataíde; Baetas, Ana Cristina; Monteiro, Marta Chagas; Maia, Cristiane do Socorro Ferraz
2012-09-28
Petiveria alliacea (Phytolaccaceae) is a perennial shrub indigenous to the Amazon Rainforest and tropical areas of Central and South America, the Caribbean, and sub-Saharan Africa. In folk medicine, Petiveria alliacea has a broad range of therapeutic properties; however, it is also associated with toxic effects. The present study evaluated the putative effects of Petiveria alliacea on the central nervous system, including locomotor activity, anxiety, depression-like behavior, and memory, and oxidative stress. Two-month-old male and female Wistar rats (n=7-10 rats/group) were administered with 900 mg/kg of hydroalcoholic extracts of Petiveria alliacea L. The behavioral assays included open-field, forced swimming, and elevated T-maze tests. The oxidative stress levels were measured in rat blood samples after behavioral assays and methemoglobin levels were measured in vitro. Consistent with previous reports, Petiveria alliacea increased locomotor activity. It also exerted previously unreported anxiolytic and antidepressant effects in behavioral tests. In the oxidative stress assays, the Petiveria alliacea extract decreased Trolox equivalent antioxidant capacity levels and increased methemoglobin levels, which was related to the toxic effects. The Petiveria alliacea extract exerted motor stimulatory and anxiolytic effects in the OF test, antidepressant effects in the FS test, and elicited memory improvement in ETM. Furthermore, the Petiveria alliacea extract also exerted pro-oxidant effects in vitro and in vivo, inhibiting the antioxidant status and increasing MetHb levels in human plasma, respectively. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
Kawaura, Kazuaki; Ogata, Yukino; Honda, Sokichi; Soeda, Fumio; Shirasaki, Tetsuya; Takahama, Kazuo
2016-04-01
We investigated whether tipepidine exerts an antidepressant-like effect in the forced swimming test in adrenocorticotropic hormone (ACTH)-treated rats, which is known as a treatment-resistant depression model, and we studied the pharmacological mechanisms of the effects of tipepidine. Male Wistar rats (5-7 weeks old) were used in this study. Tipepidine (20 and 40 mg/kg, i.p.) decreased the immobility time in the forced swimming test in ACTH-treated rats. The anti-immobility effect of tipepidine was blocked by a catecholamine-depleting agent, alpha-methyl-p-tyrosine (300 mg/kg, s.c.), but not by a serotonin-depleting agent, p-chlorophenylalanine. The anti-immobility effect of tipepidine was also blocked by a dopamine D1 receptor antagonist, SCH23390 (0.02 mg/kg, s.c.) and an adrenaline α2 receptor antagonist, yohimbine (2 mg/kg, i.p.). In microdialysis technique, tipepidine (40 mg/kg, i.p.) increased the extracellular dopamine level of the nucleus accumbens (NAc) in ACTH-treated rats. These results suggest that tipepidine exerts an antidepressant-like effect in the forced swimming test in ACTH-treated rats, and that the effect of tipepidine is mediated by the stimulation of dopamine D1 receptors and adrenaline α2 receptors. The results also suggest that an increase in the extracellular dopamine level in the NAc may be involved in the antidepressant-like effect of tipepidine in ACTH-treated rats. Copyright © 2016. Published by Elsevier B.V.
Zhang, Chao; Zhong, Lijin; Fu, Xiaotian; Wang, Jiao; Wu, Zhixuan
2016-02-16
This study reveals the spatial distribution of water withdrawal and consumption by thermal power generation and the associated water stress at catchment level in China based on a high-resolution geodatabase of electric generating units and power plants. We identified three groups of regions where the baseline water stress exerted by thermal power generation is comparatively significant: (1) the Hai River Basin/East Yellow River Basin in the north; (2) some arid catchments in Xinjiang Autonomous Region in the northwest; and (3) the coastal city clusters in the Yangtze River Delta, Pearly River Delta, and Zhejiang Province. Groundwater stress is also detected singularly in a few aquifers mainly in the Hai River Basin and the lower reaches of the Yellow River Basin. As China accelerates its pace of coal mining and coal-fired power generation in the arid northwest regions, the energy/water priorities in catchments under high water stress are noteworthy. We conclude that promotion of advanced water-efficient technologies in the energy industry and more systematic analysis of the water stress of thermal power capacity expansion in water scarce regions in inland China are needed. More comprehensive and transparent data monitoring and reporting are essential to facilitate such water stress assessment.
The influence of a yoga exercise program for young adults with intellectual disabilities.
Hawkins, Brent L; Stegall, Joanna B; Weber, Madalyn F; Ryan, Joseph B
2012-07-01
Individuals with intellectual disabilities (ID) have an increased risk of obesity and are significantly less likely to engage in physical activity compared to their nondisabled peers. A growing body of research supports the physical and mental health benefits of yoga. While the benefits of yoga have been studied across a host of populations with varying ages and physical disabilities, no studies could be identified investigating the benefits of yoga for young adults with ID. This study investigated the impact of participating in yoga classes on the amount of exercise behavior and perception of physical exertion when compared to non-structured exercise sessions between two young adults with ID in a post-secondary education setting. A single subject multiple baseline research design was implemented across two young adults with mild ID to determine the effects of a yoga exercise class on frequency of exercise behavior and perception of physical exertion when compared to non-structured exercise sessions. Partial interval recording, the Eston-Parfitt curvilinear rating of perceived exertion scale, and the physical activity enjoyment scale were implemented to collect data on dependent variables and consumer satisfaction during each non-structured exercise session and each yoga class. indicated that percentage of exercise behavior and perceived exertion levels during yoga group exercise sharply increased with large effect sizes when compared to non-structured exercise sessions.
Negative incidental emotions augment fairness sensitivity.
Liu, Cuizhen; Chai, Jing Wen; Yu, Rongjun
2016-04-22
Previous studies have shown that task-unrelated emotions induced incidentally exert carryover effects on individuals' subsequent decisions in financial negotiations. However, the specificity of these emotion effects are not clear. In three experiments, we systematically investigated the role of seven transiently induced basic emotions (disgust, sadness, anger, fear, happiness, surprise and neutral) on rejection of unfair offers using the ultimatum game. We found that all negative emotions (disgust, sadness, anger and fear), but not happiness or surprise, significantly increased rejection rates, suggesting that the effect of incidental negative emotions on fairness is not specific to the type of negative emotion. Our findings highlight the role of fleeting emotions in biasing decision-making processes and suggest that all incidental negative emotions exert similar effects on fairness sensitivity, possibly by potentiating attention towards negative aspects of the situation.
Bozkurt, Aras Adem; Mustafa, Guven; Tarık, Akman; Adile, Ozkan; Murat, Sen Halil; Mesut, Kılıcoglu; Yıldıray, Kalkan; Coskun, Silan; Murat, Cosar
2014-01-01
There are few studies on the neuroprotective effects of syringaldehyde in a rat model of cerebral ischemia. The study aimed to elucidate the mechanisms underlying the neuroprotective effects of syringaldehyde on ischemic brain cells. Rat models of cerebral ischemia were intraperitoneally administered syringaldehyde. At 6 and 24 hours after syringaldehyde administration, cell damage in the brain of cerebral ischemia rats was obviously reduced, superoxide dismutase activity and nuclear respiratory factor 1 expression in the brain tissue were markedly increased, malondiadehyde level was obviously decreased, apoptosis-related cysteine peptidase caspase-3 and -9 immunoreactivity was obviously decreased, and neurological function was markedly improved. These findings suggest that syringaldehyde exerts neuroprotective effects on cerebral ischemia injury through anti-oxidation and anti-apoptosis. PMID:25558237
Bozkurt, Aras Adem; Mustafa, Guven; Tarık, Akman; Adile, Ozkan; Murat, Sen Halil; Mesut, Kılıcoglu; Yıldıray, Kalkan; Coskun, Silan; Murat, Cosar
2014-11-01
There are few studies on the neuroprotective effects of syringaldehyde in a rat model of cerebral ischemia. The study aimed to elucidate the mechanisms underlying the neuroprotective effects of syringaldehyde on ischemic brain cells. Rat models of cerebral ischemia were intraperitoneally administered syringaldehyde. At 6 and 24 hours after syringaldehyde administration, cell damage in the brain of cerebral ischemia rats was obviously reduced, superoxide dismutase activity and nuclear respiratory factor 1 expression in the brain tissue were markedly increased, malondiadehyde level was obviously decreased, apoptosis-related cysteine peptidase caspase-3 and -9 immunoreactivity was obviously decreased, and neurological function was markedly improved. These findings suggest that syringaldehyde exerts neuroprotective effects on cerebral ischemia injury through anti-oxidation and anti-apoptosis.
CHEMICAL VERSUS SERUM TREATMENT OF EPIDEMIC MENINGITIS.
Flexner, S; Amoss, H L
1916-05-01
Claims of efficiency have been made at two widely separated periods for the chemical treatment of epidemic meningitis, in the first instance for lysol and in the second for protargol. The use of lysol was long since abandoned; the recommendation for protargol is based on a single series of cases, small in number. Because of the variable severity of epidemics of meningitis, small reliance can be placed on results of treatment limited in extent to small numbers of cases and to one locality. A more uniform and accurate measure of the value of a method of treatment is provided by animals infected experimentally with pathogenic cultures of meningococci. Young guinea pigs respond in a definite manner to intraperitoneal inoculation of virulent meningococci. Neither protargol nor lysol proved to have any curative action on the experimental infection thus produced in these animals. Monkeys respond in a characteristic manner to the inoculation of virulent cultures into the subarachnoid space. Protargol displayed no curative action on the experimental infection thus produced in these animals. On the contrary, both lysol and protargol exert antileukotactic and antiphagocytic effects, and are also potent protoplasmic poisons, and the leukocytes with which they come in contact are injured and made to degenerate. According to the extent to which these harmful properties are exerted, the chemicals promote the advance rather than restrain the progress of meningococcic infection. Recovery from meningococcic infection in man and animals is accomplished chiefly through the process of phagocytosis. The specific antiserum acts curatively by increasing the emigration of leukocytes, by promoting phagocytosis directly, and by agglutinating the meningococci, and also by neutralizing endotoxin. Any means which interfere with and reduce these essential processes retard or prevent recovery. Both lysol and protargol interfere with and diminish the emigration of leukocytes and the phagocytosis of meningococci, and neither possesses antitoxic power. The mixture of antiserum with lysol and with protargol reduces to a certain extent the antileukotactic and antiphagocytic effect of the chemicals; but this action is insufficient to set aside wholly the injurious effects which they produce. It follows, therefore, that whatever theoretical advantages might accrue from a bactericidal activity exerted by these chemicals independently of the type of meningococcus causing epidemic meningitis, is more than offset by the harmful effects which they cause. Hence specific antiserum seems to provide the logical therapeutic agent with which to combat epidemic meningitis, since it is itself innocuous and promotes those processes essential to recovery from the disease. The problem up to the present has been that of producing an antiserum which represents the several types of the meningococcus, and this problem is now in a fair way to being solved.
The effects of acclimatization on blood clotting parameters in exertional heat stress.
Vesić, Zoran; Vukasinović-Vesić, Milica; Dincić, Dragan; Surbatović, Maja; Radaković, Sonja S
2013-07-01
Exertional heat stress is a common problem in military services. Considering the coagulation abnormalities are of major importance in development of severe heat stroke, we wanted to examine changes in hemostatic parameters in soldiers during exertional heat stress test as well as the effects of a 10-day passive or active acclimatization in a climatic chamber. A total of 40 male soldiers with high aerobic capacity performed exertional heat stress test (EHST) either in cool [20 degrees C, 16 degrees C wet bulb globe temperature (WBGT)], or hot (40 degrees C, 29 degrees C, (WBGT) environment, unacclimatized (U) or after 10 days of passive (P) or active (A) acclimatization. Physiological strain was measured by tympanic temperatures (Tty) and heart rates (HR). Platelet count (PC), antithrombin III (AT), and prothrombin time (PT) were assessed in blood samples collected before and immediately after the EHST. EHST in hot conditions induced physiological heat stress (increase in Tty and HR), with a significant increase in prothrombin time in the groups U and A. Platelet counts were significantly higher after the EHST compared to the basic levels in all the investigated groups, regardless environmental conditions and acclimatization state. Antithrombin levels were not affected by EHST whatsoever. In the trained soldiers, physiological heat stress caused mild changes in some serum parameters of blood clotting such as prothrombin time, while others such as antithrombin levels were not affected. Platelet counts were increased after EHST in all groups. A 10-day passive or active acclimatization in climatic chamber showed no effect on parameters investigated.
Time-dependent efficiency measurements of donor-acceptor, dye-sensitized polymer solar cells
NASA Astrophysics Data System (ADS)
Bandaccari, Kyle; Chesmore, Grace; Tajalli-Tehrani Valverde, Parisa; Bugaj, Mitchel; McNelis, Brian; Barber, Richard, Jr.
The fullerene/polymer active layer pairing of PCBM/P3HT has become the model system within the field of polymer solar cell research. A large body of work concerned with reporting improved efficiencies for this system exists, but truly quantitative studies of device lifetime and long-term degradation tendencies are much rarer. Here, we report the effects of two donor-acceptor diazo dye sensitizers on efficiency and lifetime upon addition into the PCBM/P3HT active layer at varied concentrations. The electrical and efficiency measurements were supplemented by time-dependent UV-visible spectroscopy studies and morphology investigations via atomic-force microscopy (AFM). This pairing with spectroscopy offers an internal check on the data as the rate of change in absorbance of the active layer correlates almost exactly to the rate of power conversion efficiency decrease. Additionally, AFM imaging reveals different morphology patterns when dye concentrations and functionalities change. Such observations suggest that such small-molecule sensitizers exert yet undetermined effects on the organization of components within the active layer at the molecular level.
Protective ability against oxidative stress of brewers' spent grain protein hydrolysates.
Vieira, Elsa F; da Silva, Diana Dias; Carmo, Helena; Ferreira, Isabel M P L V O
2017-08-01
The protein fraction of Brewers' spent grain (BSG) was used as substrate to obtain hydrolysates with antioxidant activity. Three enzymatic approaches were applied: brewer's spent yeast (BSY) proteases, Neutrase® and Alcalase®, at the same proteolytic activity (1U/mL), using an enzyme/substrate ratio of 10:100 (v/v), at 50°C, 4h. Total Phenolic Content (TPC) and Ferric Ion Reducing Antioxidant Power (FRAP) of hydrolysates and fractions <10kDa and <3kDa were assayed. Additionally, the protective ability of <10kDa fractions against oxidative stress on Caco-2 and HepG2 cells was investigated. Alcalase® hydrolysate presented significantly (p<0.05) higher TPC and FRAP (0.083mgGAE/mgdw; 0.101mgTE/mgdw, respectively) than Neutrase® and BSY hydrolysates. The three BSG protein hydrolysates (fraction <10kDa) exerted protective effect against free-radical induced cytotoxicity in Caco-2 and HepG2 cell lines, but the strongest effect was observed for BSY hydrolysates, therefore, it presents greater potential as functional ingredient. Copyright © 2017 Elsevier Ltd. All rights reserved.
Di Giorgio, C; Boyer, L; De Meo, M; Laurant, C; Elias, R; Ollivier, E
2015-07-01
DIG, a liquid herbal preparation made from a mixture of diluted mother tinctures of Berberis vulgaris, Taraxacum officinale and Arctium lappa, was assessed for its antimutagenic properties against mitomycin C. The micronucleus assay on Chinese hamster ovary (CHO)-K1 cells was used to evaluate the in vitro anticlastogenic activity of DIG compared to those of separately diluted mother tinctures. The micronucleus assay was performed on mouse erythrocytes and the comet assay was performed on mouse liver, kidney, lung, brain and testicles to assess the protective effects of DIG (0.2 and 2 % at libitum) against an intraperitoneal injection of mitomycin C (1 mg Kg(-1)) in mice. DIG exerted a powerful anticlastogenic activity, under both pretreatment and simultaneous treatment conditions as assessed by the micronucleus assay in CHO-K1 cells. Its protective activity was greater than that observed for each mother tincture. DIG reduced micronuclei levels in mouse erythrocytes and suppressed >80 % of DNA strand breaks in the liver, kidney, lung, brain and testicles of mice exposed to mitomycin C.
Seng, Melvin; Wee, Liang En; Zhao, Xiahong; Cook, Alex R; Chia, Sin Eng; Lee, Vernon J
2017-07-06
This study aimed to determine if disposable filtering facepiece respirators (FFRs), with exhalation valve (EV) and a novel active venting system (AVS), provided greater perceived comfort and exertion when compared to standard N95 FFRs without these features among male military personnel performing prolonged essential outdoor duties. We used a randomised open-label controlled crossover study design to compare three FFR options: (a) standard FFR; (b) FFR with EV; and (c) FFR with EV+AVS. Male military personnel aged between 18 and 20 years completed a questionnaire at the beginning (baseline), after two hours of standardised non-strenuous outdoor duty and after 12 hours of duty divided into two-hour work-rest cycles. Participants rated the degree of discomfort, exertion and symptoms using a five-point Likert scale. The association between outcomes and the types of FFR was assessed using a multivariate ordered probit mixed-effects model. For a majority of the symptoms, study participants rated FFR with EV and FFR with EV+AVS with significantly better scores than standard FFR. Both FFR with EV and FFR with EV+AVS had significantly less discomfort (FFR with EV+AVS: 91.1%; FFR with EV: 57.6%) and exertion (FFR with EV+AVS: 83.5%; FFR with EV: 34.4%) than standard FFR. FFR with EV+AVS also had significantly better scores for exertion (53.4%) and comfort (39.4%) when compared to FFR with EV. Usage of FFR with EV+AVS resulted in significantly reduced symptoms, discomfort and exertion when compared to FFR with EV and standard FFR.
Dual towline spin-recovery device
NASA Technical Reports Server (NTRS)
White, W. L. (Inventor)
1985-01-01
A device which corrects aerodynamic spin is described wherein a parachute exerts antispin forces on an aircraft to effect spin recovery. The dual parachute towlines and are each attached to the parachute and are attached to the rear fuselage equidistant to and on opposite sides of the aircraft centerline. As the parachute is deployed during spin, the parachute force acts through only the towing and exerts its force outboard of center on the aircraft. As a result, the parachute exerts not only an antispin torque, but additionally causes the aircraft to roll, creating a gyroscopic antispin rolling moment. The additional antispin rolling moment facilitates spin recovery by permitting a relatively smaller parachute to accomplish spin recovery equivalent to that of a larger parachute attached to the center of the rear fuselage.
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.
Clove oil induces anaesthesia and blunts muscle contraction power in three Amazon fish species.
Fujimoto, Rodrigo Yudi; Pereira, Débora Martins; Silva, Jessica Cristina Souza; de Oliveira, Laís Cássia Araújo; Inoue, Luis Antonio Kioshi Aoki; Hamoy, Moisés; de Mello, Vanessa Jóia; Torres, Marcelo Ferreira; Barbas, Luis André Luz
2018-02-01
Clove oil is used as an anaesthetic for many species of fish worldwide; however, relatively few studies have assessed its effectiveness on Amazon fish species and no compelling evidence has ever been reported on the relaxant properties of this oil for skeletal muscle of fish. Thus, the objective of this study was to evaluate the latencies to deep anaesthesia and recovery, along with the myorelaxant effect of clove oil on three Amazon fish species: cardinal tetra, Paracheirodon axelrodi, banded cichlid, Heros severus and angelfish, Pterophyllum scalare, submitted to short-term anaesthetic baths. Fish were assayed in three groups of 60 fish each and individually anaesthetized in a completely randomized design with six clove oil concentrations using 10 fish/species/concentration. Electromyographic recordings from dorsal muscle were performed during stages of induction and recovery in which nine fish/species/stage were used. Deep anaesthesia was attained for all concentrations tested, and no mortalities were observed throughout the experiments and after a 48-h observation period. Concentration of 90 μL L -1 and above promoted fast deep anaesthesia (< 3 min) and calm recovery in angelfish and cardinal tetra, whereas the concentration of 60 μL L -1 sufficed to quickly anaesthetize banded cichlid. Times to full recovery were not significantly contrasting among species and occurred within appropriate time threshold (< 5 min). Clove oil exerted a conspicuous depression of muscle contraction power, and therefore can be effectively used as a muscle relaxant agent for P. scalare, P. axelrodi, H. severus and potentially, for other fish species.
Prolonged self-paced exercise in the heat – environmental factors affecting performance
Junge, Nicklas; Jørgensen, Rasmus; Flouris, Andreas D.; Nybo, Lars
2016-01-01
ABSTRACT In this review we examine how self-paced performance is affected by environmental heat stress factors during cycling time trial performance as well as considering the effects of exercise mode and heat acclimatization. Mean power output during prolonged cycling time trials in the heat (≥30°C) was on average reduced by 15% in the 14 studies that fulfilled the inclusion criteria. Ambient temperature per se was a poor predictor of the integrated environmental heat stress and 2 of the prevailing heat stress indices (WBGT and UTCI) failed to predict the environmental influence on performance. The weighing of wind speed appears to be too low for predicting the effect for cycling in trained acclimatized subjects, where performance may be maintained in outdoor time trials at ambient temperatures as high as 36°C (36°C UTCI; 28°C WBGT). Power output during indoor trials may also be maintained with temperatures up to at least 27°C when humidity is modest and wind speed matches the movement speed generated during outdoor cycling, whereas marked reductions are observed when air movement is minimal. For running, representing an exercise mode with lower movement speed and higher heat production for a given metabolic rate, it appears that endurance is affected even at much lower ambient temperatures. On this basis we conclude that environmental heat stress impacts self-paced endurance performance. However, the effect is markedly modified by acclimatization status and exercise mode, as the wind generated by the exercise (movement speed) or the environment (natural or fan air movement) exerts a strong influence. PMID:28090557
DING, Zhen; LI, Jintao; LI, Fan; MEPHRYAR, Mohammadreza Mohammadzad; WU, Shuicai; ZHANG, Chen; ZENG, Yi
2017-01-01
Background: The extremely low-frequency electromagnetic field (ELF-EMF), mainly emitted by electric transmission lines and household electronic appliances, is becoming a worldwide health risk. It is imperative to investigate the biological impacts of ELF-EMF and to identify products that are resistant to the radiation from 50 Hz ELF-EMF. In this study, we investigated the biological impacts of apoptosis caused by 50 Hz Power line ELF-EMF and the protective effects of Vit C and Vit E. Methods: We conducted this study in Beijing, China in 2013. B95-8 and Balb/c-3T3 cells were divided into a sham group, an expo group and 3 expo groups in which the cells were preincubated with various concentrations of Vit C and Vit E. Then, all of the cells were exposed to 50 Hz Power line ELF-EMF and examined for apoptosis. The cells were collected for apoptosis detection after exposure. Results: The percent of cells that undergoing apoptosis and preincubated with various concentrations of Vit C and Vit E were significantly lower than in the Expo group. Conclusion: Vit C and Vit E exert significant protective effects from 50 Hz ELF-EMF radiation. The optimal protective concentrations of Vit C and Vit E are 10 μmol/L and 25 μmol/L, respectively. The protective effect of vitamins was more apparent for Balb/c-3T3 cells than B95-8 cells. PMID:28451526
Selection dynamic of Escherichia coli host in M13 combinatorial peptide phage display libraries.
Zanconato, Stefano; Minervini, Giovanni; Poli, Irene; De Lucrezia, Davide
2011-01-01
Phage display relies on an iterative cycle of selection and amplification of random combinatorial libraries to enrich the initial population of those peptides that satisfy a priori chosen criteria. The effectiveness of any phage display protocol depends directly on library amino acid sequence diversity and the strength of the selection procedure. In this study we monitored the dynamics of the selective pressure exerted by the host organism on a random peptide library in the absence of any additional selection pressure. The results indicate that sequence censorship exerted by Escherichia coli dramatically reduces library diversity and can significantly impair phage display effectiveness.
Schulman, Ariel; Chaimowitz, Matthew; Choudhury, Muhammad; Eshghi, Majid; Konno, Sensuke
2016-01-01
Background The pathogenesis of nephrolithiasis (kidney stone) remains elusive, while several therapeutic options are available but not effective as we expected. Accumulating data yet suggest that oxidative stress (generation of oxygen free radicals) may play a primary role in its occurrence. Particularly, calcium oxalate (CaOx) is a key element in the most common form (> 75%) of kidney stones, and its crystal form known as CaOx monohydrate (COM) has been shown to exert oxidative stress, facilitating CaOx stone formation. Hence, diminishing oxidative stress with certain antioxidants could be a potential strategic approach. We are interested in a bioactive extract of Poria mushroom, PE, which has been shown to have antioxidant and renoprotective activities. Accordingly, we investigated if PE might have antioxidant activity that would have implication in prevention of kidney stone formation. Methods Renal epithelial LLC-PK1 cells were employed and exposed to COM or hydrogen peroxide (H2O2) as a positive control capable of exerting oxidative stress. Possible antioxidant and protective effects of PE against oxidative stress (exerted by COM or H2O2) were assessed by cell viability test and lipid peroxidation (LPO) assay. To explore its protective mechanism, two glycolytic parameters, hexokinase (HK) activity and ATP synthesis, were examined and cell cycle analysis was also performed. Results Both H2O2 and COM led to a significant (P < 0.05) reduction in cell viability, accompanied by severe oxidative stress assessed by LPO assay. Such oxidative stress also caused the significant decline in HK activity and cellular ATP level, indicating the inhibition of glycolysis. Cell cycle analysis further indicated that oxidative stress interfered with cell cycle, inducing a G1 cell cycle arrest that presumably results in the cessation of cell proliferation. However, PE was capable of significantly preventing or diminishing all these cellular effects mediated through oxidative stress (exerted by H2O2 and COM). Conclusions The present study shows that the mushroom extract PE appears to have antioxidant and renoprotective effects against oxidative stress exerted by COM in renal cells. Therefore, PE with antioxidant activity is considered a promising natural agent that may have clinical implications in prevention of nephrolithiasis primarily induced by oxidative stress. PMID:27829958
NASA Astrophysics Data System (ADS)
Felderhof, B. U.
2017-09-01
Translational and rotational swimming at small Reynolds numbers of a planar assembly of identical spheres immersed in an incompressible viscous fluid is studied on the basis of a set of equations of motion for the individual spheres. The motion of the spheres is caused by actuating forces and forces derived from a direct interaction potential, as well as hydrodynamic forces exerted by the fluid as frictional and added mass hydrodynamic interactions. The translational and rotational swimming velocities of the assembly are deduced from momentum and angular momentum balance equations. The mean power required during a period is calculated from an instantaneous power equation. Expressions are derived for the mean swimming velocities and the mean power, valid to second order in the amplitude of displacements from the relative equilibrium positions. Hence these quantities can be evaluated for prescribed periodic displacements. Explicit calculations are performed for three spheres interacting such that they form an equilateral triangle in the rest frame of the configuration.
High-pressure microhydraulic actuator
Mosier, Bruce P [San Francisco, CA; Crocker, Robert W [Fremont, CA; Patel, Kamlesh D [Dublin, CA
2008-06-10
Electrokinetic ("EK") pumps convert electric to mechanical work when an electric field exerts a body force on ions in the Debye layer of a fluid in a packed bed, which then viscously drags the fluid. Porous silica and polymer monoliths (2.5-mm O.D., and 6-mm to 10-mm length) having a narrow pore size distribution have been developed that are capable of large pressure gradients (250-500 psi/mm) when large electric fields (1000-1500 V/cm) are applied. Flowrates up to 200 .mu.L/min and delivery pressures up to 1200 psi have been demonstrated. Forces up to 5 lb-force at 0.5 mm/s (12 mW) have been demonstrated with a battery-powered DC-DC converter. Hydraulic power of 17 mW (900 psi@ 180 uL/min) has been demonstrated with wall-powered high voltage supplies. The force and stroke delivered by an actuator utilizing an EK pump are shown to exceed the output of solenoids, stepper motors, and DC motors of similar size, despite the low thermodynamic efficiency.
Gasification of torrefied fuel at power generation for decentralized consumers
NASA Astrophysics Data System (ADS)
Safin, R. R.; Khakimzyanov, I. F.; Galyavetdinov, N. R.; Mukhametzyanov, S. R.
2017-10-01
The increasing need of satisfaction of the existing needs of the population and the industry for electric energy, especially in the areas remote from the centralized energy supply, results in need of development of “small-scale energy generation”. At the same time, the basis in these regions is made by the energy stations, using imported fuel, which involve a problem of increase in cost and transportation of fuel to the place of consumption. The solution of this task is the use of the torrefied waste of woodworking and agricultural industry as fuel. The influence of temperature of torrefaction of wood fuel on the developed electric generator power is considered in the article. As a result of the experiments, it is revealed that at gasification of torrefied fuel from vegetable raw material, the generating gas with the increased content of hydrogen and carbon oxide, in comparison with gasification of the raw materials, is produced. Owing to this, the engine capacity increases that exerts direct impact on power generation by the electric generator.
2013-01-01
Using a large, nationally representative longitudinal sample of Chinese aged 65 and older, this study examines the effects of childhood, adult, and community socioeconomic conditions on mortality and several major health outcomes. The role of social mobility is also tested. We find that childhood socioeconomic conditions exert long-term effects on functional limitations, cognitive impairment, self-rated health, and mortality independent of adult and community socioeconomic conditions. Achieved conditions matter for most outcomes as well, considering that adult and community socioeconomic conditions have additional impacts on health among Chinese elders. The majority of the effects of childhood conditions are not mediated by adult and community conditions. The results also show that social mobility and health in later life are linked in complex ways and that psychosocial factors have marginal explanatory power for the effects of socioeconomic conditions. Overall, this study provides new longitudinal evidence from China to support the notion that health and mortality at older ages are influenced by long-term and dynamic processes structured by the social stratification system. We discuss our findings in the context of the life course and ecological perspective, emphasizing that human development is influenced by a nexus of social experiences that impact individuals throughout life. PMID:21394657
DOE Office of Scientific and Technical Information (OSTI.GOV)
Iqbal, Nida; Abdul Kadir, Mohammed Rafiq, E-mail: rafiq@biomedical.utm.my; Nik Malek, Nik Ahmad Nazim
Highlights: • Stable nano sized silver substitute hydroxyapatite is prepared under surfactant assisted microwave process at 600 W power for 7 min. • The nanoparticles are in the size range of 58–72 nm and exert uniform elongated spheroid morphology. • Increase in silver concentration resulted in better dielectric properties. • Good antibacterial activity and silver release. - Abstract: The present study reports a relatively simple method for the synthesis of stable silver substituted hydroxyapatite nanoparticles with controlled morphology and particle size. In order to achieve this, CTAB is included as a surfactant in the microwave refluxing process (600 W formore » 7 min). The nanoparticles produced with different silver ion concentrations (0.05, 0.1 and 0.2 wt%) were characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscope (FESEM), energy dispersive X-ray (EDX) and Brunauer–Emmett–Teller (BET) analysis. XRD and FTIR analyses reveal that the Ag-HA nanoparticles were phase pure at 1000 °C. FESEM images showed that the produced nanoparticles are in the size range of 58–72 nm and exert uniform elongated spheroid morphology. The dielectric properties suggest that the increase in dielectric constant (ε′) and dissipation factor (D) values with increasing Ag concentrations. Antibacterial performance of the Ag-HA samples elucidated using disk diffusion technique (DDT) and minimum inhibitory concentration (MIC) demonstrates anti-bacterial activity against Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa and Escherichia coli. This effect was dose dependent and was more pronounced against Gram-negative bacteria than Gram-positive organisms.« less
Rodrigues, Tigressa Helena Soares; Rocha, Maria Valderez Ponte; de Macedo, Gorete Ribeiro; Gonçalves, Luciana R B
2011-07-01
In this work, the potential of microwave-assisted alkali pretreatment in order to improve the rupture of the recalcitrant structures of the cashew able bagasse (CAB), lignocellulosic by-product in Brazil with no commercial value, is obtained from cashew apple process to juice production, was studied. First, biomass composition of CAB was determined, and the percentage of glucan and lignin was 20.54 ± 0.70% and 33.80 ± 1.30%, respectively. CAB content in terms of cellulose, hemicelluloses, and lignin, 19.21 ± 0.35%, 12.05 ± 0.37%, and 38.11 ± 0.08%, respectively, was also determined. Results showed that, after enzymatic hydrolysis, alkali concentration exerted influence on glucose formation, after pretreatment with 0.2 and 1.0 mo L(-1) of NaOH (372 ± 12 and 355 ± 37 mg g(glucan)(-1) ) when 2% (w/v) of cashew apple bagasse pretreated by microwave-assisted alkali pretreatment (CAB-M) was used. On the other hand, pretreatment time (15-30 min) and microwave power (600-900 W) exerted no significant effect on hydrolysis. On enzymatic hydrolysis step, improvement on solid percentage (16% w/v) and enzyme load (30 FPU g (CAB-M) (-1) ) increased glucose concentration to 15 g L(-1). The fermentation of the hydrolyzate by Saccharomyces cerevesiae resulted in ethanol concentration and productivity of 5.6 g L(-1) and 1.41 g L(-1) h(-1), respectively.
The perceived effects of drug messages on use patterns in adolescents.
Mayton, D M; Nagel, E A; Parker, R
1990-01-01
Following a survey of over 5,000 students in north central Idaho and southeast Washington, an interviewing strategy was implemented with 223 adolescents randomly selected by their principals. The strategy was designed to learn: 1) which sources have utility and credibility with youth in providing drug information; 2) whether different message content and delivery style have differential effects upon that group; and 3) whether widely held perceptions voiced by parents and teachers about their ineffectiveness as information sources were accurate. Double-blind interviews, arranged to protect respondent anonymity, were conducted by trained interviewers from a research methods class. No interview was held when either an interviewer or respondent knew the other. Among the important findings of the study were that: 1) parents and teachers are trusted, credible sources of drug information; 2) doctors, nurses, law officers, and clergy are also credible but not visible to youth; 3) the evil media and celebrity fears of parents and teachers are largely ungrounded in adolescent perception; and 4) factual information from credible sources emphasizing the range of types of negative consequences associated with drug use can exert powerful effects upon adolescents' reported personal use of drugs.
Tolazoline decreases survival time during microwave-induced lethal heat stress in anesthetized rats
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jauchem, J.R.; Chang, K.S.; Frei, M.R.
1996-03-01
Effects of {alpha}-adrenergic antagonists have been studied during environmental heating but not during microwave-induced heating. Tolazoline may exert some of its effects via {alpha}-adrenergic blockade. In the present study, ketamine-anesthetized Sprague-Dawley rats were exposed to 2450-MHz microwaves at an average power density of 60 mW/cm{sup 2} (whole-body specific absorption rate of approximately 14 W/kg) until lethal temperatures were attained. The effects of tolazoline (10 mg/kg body weight) on physiological responses (including changes in body temperature, heart rate, blood pressure, and respiratory rate) were examined. Survival time was significantly shorter in the tolazoline group than in saline-treated animals. In general, heartmore » rate and blood pressure responses were similar to those that occur during environmental heat stress. Heart rate, however, was significantly elevated in animals that received tolazoline, both before and during terminal microwave exposure. It is possible that changes associated with the elevated heart rate (e.g., less cardiac filling) in tolazoline-treated animals resulted in greater susceptibility to microwave-induced heating and the lower survival time. 47 refs., 3 figs., 2 tabs.« less
Chirullo, B; Sgarbanti, R; Limongi, D; Shytaj, I L; Alvarez, D; Das, B; Boe, A; DaFonseca, S; Chomont, N; Liotta, L; III Petricoin, E; Norelli, S; Pelosi, E; Garaci, E; Savarino, A; Palamara, A T
2013-01-01
Central memory (TCM) and transitional memory (TTM) CD4+ T cells are known to be the major cellular reservoirs for HIV, as these cells can harbor a transcriptionally silent form of viral DNA that is not targeted by either the immune system or current antiretroviral drug regimens. In the present study, we explored the molecular bases of the anti-HIV reservoir effects of auranofin (AF), a pro-oxidant gold-based drug and a candidate compound for a cure of AIDS. We here show that TCM and TTM lymphocytes have lower baseline antioxidant defenses as compared with their naive counterpart. These differences are mirrored by the effects exerted by AF on T-lymphocytes: AF was able to exert a pro-differentiating and pro-apoptotic effect, which was more pronounced in the memory subsets. AF induced an early activation of the p38 mitogen-activated protein kinase (p38 MAPK) followed by mitochondrial depolarization and a final burst in intracellular peroxides. The pro-differentiating effect was characterized by a downregulation of the CD27 marker expression. Interestingly, AF-induced apoptosis was inhibited by pyruvate, a well-known peroxide scavenger, but pyruvate did not inhibit the pro-differentiating effect of AF, indicating that the pro-apoptotic and pro-differentiating effects involve different pathways. In conclusion, our results demonstrate that AF selectively targets the TCM/TTM lymphocyte subsets, which encompass the HIV reservoir, by affecting redox-sensitive cell death pathways. PMID:24309931
Principal-Staff Relations: Situational Mediator of Effectiveness
ERIC Educational Resources Information Center
Williams, Leonard B.; Hoy, Wayne K.
1971-01-01
Explores the usefulness of the "Contingency Model" of leadership effectiveness -- effectiveness of a group is contingent upon the relationship between leadership style and the degree to which the situation enables the leader to exert his influence. (Author)
NASA Technical Reports Server (NTRS)
Ehihara, Keikiti
1944-01-01
In internal combustion engines, steam engines, air compressors, and so forth, the piston ring plays an important role. Especially, the recent development of Diesel engines which require a high compression pressure for their working, makes, nowadays, the packing action of the piston ring far more important than ever. Though a number of papers have been published in regard to researches on the problem of the piston ring, none has yet dealt with an exact measurement of pressure exerted on the cylinder wall at any given point of the ring. The only paper that can be traced on this subject so far is Mr. Nakagawa's report on the determination of the relative distribution of pressure on the cylinder wall, but the measuring method adopted therein appears to need further consideration. No exact idea has yet been obtained as to how the obturation of gas between the piston and cylinder, the frictional resistance of the piston, and the wear of the cylinder wall are affected by the intensity and the distribution of the radial pressure of the piston ring. Consequently, the author has endeavored, by employing an apparatus of his own invention, to get an exact determination of the pressure distribution of the piston ring. By means of a newly devised ring tester, to which piezoelectricity of quartz was applied, the distribution of the radial pressure of many sample rings on the market was accurately determined. Since many famous piston rings show very irregular pressure distribution, the author investigated and achieved a manufacturing process of the piston ring which will exert uniform pressure on the cylinder wall. Temperature effects on the configuration and on the mean spring power have also been studied. Further, the tests were performed to ascertain how the gas tightness of the piston ring may be affected by the number or spring power. The researches as to the frictional resistance between the piston ring and the cylinder wall were carried out, too. The procedure of study, and experiments conducted by the author, on this subject will be fully described in the following paragraphs.
Magnetohydrodynamic Turbulence in the Plasmoid-mediated Regime
NASA Astrophysics Data System (ADS)
Comisso, L.; Huang, Y.-M.; Lingam, M.; Hirvijoki, E.; Bhattacharjee, A.
2018-02-01
Magnetohydrodynamic turbulence and magnetic reconnection are ubiquitous in astrophysical environments. In most situations these processes do not occur in isolation but interact with each other. This renders a comprehensive theory of these processes highly challenging. Here we propose a theory of magnetohydrodynamic turbulence driven at a large scale that self-consistently accounts for the mutual interplay with magnetic reconnection occurring at smaller scales. Magnetic reconnection produces plasmoids (flux ropes) that grow from turbulence-generated noise and eventually disrupt the sheet-like structures in which they are born. The disruption of these structures leads to a modification of the turbulent energy cascade, which in turn exerts a feedback effect on the plasmoid formation via the turbulence-generated noise. The energy spectrum in this plasmoid-mediated range steepens relative to the standard inertial range and does not follow a simple power law. As a result of the complex interplay between turbulence and reconnection, we also find that the length scale that marks the beginning of the plasmoid-mediated range and the dissipation length scale do not obey true power laws. The transitional magnetic Reynolds number above which the plasmoid formation becomes statistically significant enough to affect the turbulent cascade is fairly modest, implying that plasmoids are expected to modify the turbulent path to dissipation in many astrophysical systems.
Magnetohydrodynamic Turbulence in the Plasmoid-mediated Regime
DOE Office of Scientific and Technical Information (OSTI.GOV)
Comisso, L.; Huang, Y. -M.; Lingam, M.
Magnetohydrodynamic turbulence and magnetic reconnection are ubiquitous in astrophysical environments. In most situations these processes do not occur in isolation but interact with each other. This renders a comprehensive theory of these processes highly challenging. Here we propose a theory of magnetohydrodynamic turbulence driven at a large scale that self-consistently accounts for the mutual interplay with magnetic reconnection occurring at smaller scales. Magnetic reconnection produces plasmoids (flux ropes) that grow from turbulence-generated noise and eventually disrupt the sheet-like structures in which they are born. The disruption of these structures leads to a modification of the turbulent energy cascade, which inmore » turn exerts a feedback effect on the plasmoid formation via the turbulence-generated noise. The energy spectrum in this plasmoid-mediated range steepens relative to the standard inertial range and does not follow a simple power law. As a result of the complex interplay between turbulence and reconnection, we also find that the length scale that marks the beginning of the plasmoid-mediated range and the dissipation length scale do not obey true power laws. The transitional magnetic Reynolds number above which the plasmoid formation becomes statistically significant enough to affect the turbulent cascade is fairly modest, implying that plasmoids are expected to modify the turbulent path to dissipation in many astrophysical systems« less
Magnetohydrodynamic Turbulence in the Plasmoid-mediated Regime
Comisso, L.; Huang, Y. -M.; Lingam, M.; ...
2018-02-16
Magnetohydrodynamic turbulence and magnetic reconnection are ubiquitous in astrophysical environments. In most situations these processes do not occur in isolation but interact with each other. This renders a comprehensive theory of these processes highly challenging. Here we propose a theory of magnetohydrodynamic turbulence driven at a large scale that self-consistently accounts for the mutual interplay with magnetic reconnection occurring at smaller scales. Magnetic reconnection produces plasmoids (flux ropes) that grow from turbulence-generated noise and eventually disrupt the sheet-like structures in which they are born. The disruption of these structures leads to a modification of the turbulent energy cascade, which inmore » turn exerts a feedback effect on the plasmoid formation via the turbulence-generated noise. The energy spectrum in this plasmoid-mediated range steepens relative to the standard inertial range and does not follow a simple power law. As a result of the complex interplay between turbulence and reconnection, we also find that the length scale that marks the beginning of the plasmoid-mediated range and the dissipation length scale do not obey true power laws. The transitional magnetic Reynolds number above which the plasmoid formation becomes statistically significant enough to affect the turbulent cascade is fairly modest, implying that plasmoids are expected to modify the turbulent path to dissipation in many astrophysical systems« less
Complex Dynamics of Equatorial Scintillation
NASA Astrophysics Data System (ADS)
Piersanti, Mirko; Materassi, Massimo; Forte, Biagio; Cicone, Antonio
2017-04-01
Radio power scintillation, namely highly irregular fluctuations of the power of trans-ionospheric GNSS signals, is the effect of ionospheric plasma turbulence. The scintillation patterns on radio signals crossing the medium inherit the ionospheric turbulence characteristics of inter-scale coupling, local randomness and large time variability. On this basis, the remote sensing of local features of the turbulent plasma is feasible by studying radio scintillation induced by the ionosphere. The distinctive character of intermittent turbulent media depends on the fluctuations on the space- and time-scale statistical properties of the medium. Hence, assessing how the signal fluctuation properties vary under different Helio-Geophysical conditions will help to understand the corresponding dynamics of the turbulent medium crossed by the signal. Data analysis tools, provided by complex system science, appear to be best fitting to study the response of a turbulent medium, as the Earth's equatorial ionosphere, to the non-linear forcing exerted by the Solar Wind (SW). In particular we used the Adaptive Local Iterative Filtering, the Wavelet analysis and the Information theory data analysis tool. We have analysed the radio scintillation and ionospheric fluctuation data at low latitude focusing on the time and space multi-scale variability and on the causal relationship between forcing factors from the SW environment and the ionospheric response.
He, C; Chen, Q-H; Ye, J-N; Li, C; Yang, L; Zhang, J; Xia, J-X; Hu, Z-A
2015-06-25
The hypocretin signaling is thought to play a critical role in maintaining wakefulness via stimulating the subcortical arousal pathways. Although the cortical areas, including the medial prefrontal cortex (mPFC), receive dense hypocretinergic fibers and express its receptors, it remains unclear whether the hypocretins can directly regulate the neural activity of the mPFC in vivo. In the present study, using multiple-channel single-unit recording study, we found that infusion of the SB-334867, a blocker for the Hcrtr1, beside the recording sites within the mPFC substantially exerted an inhibitory effect on the putative pyramidal neuron (PPN) activity in naturally behaving rats. In addition, functional blockade of the Hcrtr1 also selectively reduced the power of the gamma oscillations. The PPN activity and the power of the neural oscillations were not affected after microinjection of the TCS-OX2-29, a blocker for the Hcrtr2, within the mPFC. Together, these data indicate that endogenous hypocretins acting on the Hcrtr1 are required for the normal neural activity in the mPFC in vivo, and thus might directly contribute cortical arousal and mPFC-dependent cognitive processes. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.
Flow-assisted single-beam optothermal manipulation of microparticles.
Liu, Yangyang; Poon, Andrew W
2010-08-16
An optothermal tweezer was developed with a single-beam laser at 1550 nm for manipulation of colloidal microparticles. Strong absorption in water can thermally induce a localized flow, which exerts a Stokes' drag on the particles that complements the gradient force. Long-range capturing of 6 microm polystyrene particles over approximately 176 microm was observed with a tweezing power of approximately 7 mW. Transportation and levitation, targeted deposition and selective levitation of particles were explored to experimentally demonstrate the versatility of the optothermal tweezer as a multipurpose particle manipulation tool.
ERIC Educational Resources Information Center
Escobar Alméciga, Wilder Yesid
2013-01-01
This article addresses a critical problem about asymmetrical power relationships and uneven conditions in English language education exerted via identity shaping discourses in the document Educación: "Visión 2019" issued by the Colombian Ministry of National Education. The study follows the critical discourse analysis method. It…
Improvement of 10-km time-trial cycling with motivational self-talk compared with neutral self-talk.
Barwood, Martin J; Corbett, Jo; Wagstaff, Christopher R D; McVeigh, Dan; Thelwell, Richard C
2015-03-01
Unpleasant physical sensations during maximal exercise may manifest themselves as negative cognitions that impair performance, alter pacing, and are linked to increased rating of perceived exertion (RPE). This study examined whether motivational self-talk (M-ST) could reduce RPE and change pacing strategy, thereby enhancing 10-km time-trial (TT) cycling performance in contrast to neutral self-talk (N-ST). Fourteen men undertook 4 TTs, TT1-TT4. After TT2, participants were matched into groups based on TT2 completion time and underwent M-ST (n=7) or N-ST (n=7) after TT3. Performance, power output, RPE, and oxygen uptake (VO2) were compared across 1-km segments using ANOVA. Confidence intervals (95%CI) were calculated for performance data. After TT3 (ie, before intervention), completion times were not different between groups (M-ST, 1120±113 s; N-ST, 1150±110 s). After M-ST, TT4 completion time was faster (1078±96 s); the N-ST remained similar (1165±111 s). The M-ST group achieved this through a higher power output and VO2 in TT4 (6th-10th km). RPE was unchanged. CI data indicated the likely true performance effect lay between 13- and 71-s improvement (TT4 vs TT3). M-ST improved endurance performance and enabled a higher power output, whereas N-ST induced no change. The VO2 response matched the increase in power output, yet RPE was unchanged, thereby inferring a perceptual benefit through M-ST. The valence and content of self-talk are important determinants of the efficacy of this intervention. These findings are primarily discussed in the context of the psychobiological model of pacing.
Extracorporeal shock waves: perspectives in malignant tumor treatment.
Frairia, R; Berta, L; Catalano, M G
2016-01-01
Progress in basic research led to the design of new generations of anticancer drugs with some notable achievements. Over the years, more and more powerful drugs have been developed with the purpose of increasing the rate of response to therapy. As molecular power of chemotherapeutic agents increased, unfortunately also toxicity and undesired side-effects increased. The search for new therapeutic strategies to be used in the management of cancer is one of the more promising strategies to reduce chemotherapy toxicity. Extracorporeal Shock Waves (ESW), widely used for the treatment of urolithiasis, have been reported to cause modifications of cell growth both in vitro and in vivo. They exert an agonist cytotoxic effect with several chemotherapeutic agents, such as cisplatin, doxorubicin, bleomycin, paclitaxel. Moreover, as it has been reported that their main mechanism of action is an increase in cell membrane permeability, ESW are also used to deliver oligonucleotides and other small particles to cells. Recently, it was found that certain dye compounds, in particular porphyrins, can achieve a cytopathogenic effect when the disease site is subjected to ultrasound irradiation. This technique is referred to as sonodynamic therapy. Based on the new knowledge regarding the interaction between ultrasound with bulk liquid, several studies have shown a synergic effect of ESW and porphyrins in vitro, thus opening a new perspective in sonodynamic therapy, able to overcome some drawbacks encountered during conventional anticancer drug treatment. Finally, current advances in bioengineering encouraged the application of nano-scale technologies to medicine. Nanobubbles, composed of an external shell and a gas core, can deliver chemotropic drugs and porfirins, to target tumour tissues in response to physical triggers, and ESW features make them an ideal alternative to ultrasound in combination with drug-loaded nanobubbles in delivery strategies.
Móricz, Ágnes M; Ott, Péter G; Morlock, Gertrud E
2018-03-30
The knowledge about the activity of polyacetylenes was extended by their new acetylcholinesterase inhibition and antibacterial activity against plant pathogenic bacteria. For this discovery, an utmost streamlined workflow, which we consider to be of high potential in the field of natural product or superfood search was developed. It demonstrates the combined power of biological, biochemical and chemical fingerprints. Bioactive components of tansy (Tanacetum vulgare L.) root extract were profiled and identified by high-performance thin-layer chromatography hyphenated with in situ effect-directed analysis, chemical derivatizations and high-resolution mass spectrometry (HPTLC-UV/Vis/FLD-EDA-HRMS). The effect-directed profiling was performed using four bacterial bioassays including two plant pathogens, an antioxidant assay and acetyl- and butyrylcholinesterase inhibitory assays. The chromatographic, spectral and powerful mass spectrometric study of zones that exerted substantial antibacterial and/or antioxidant and/or acetylcholinesterase inhibitory effects allowed these multi-potent zones to be identified as polyacetylenes. Five polyacetylene compounds were assigned to be 2-non-1-ene-3,5,7-triynyl-3-vinyl-oxirane, 2-(2,4-hexadiynylidene)-3,4-epoxy-1,6-dioxaspiro[4.5]decane, trans- and cis-2-(2,4-hexadiynylidene)-1,6-dioxaspiro[4.5]dec-3-ene and tetradeca-2,4,6-triine-8-en-12-one. This study clearly showed the advantage of the combined use of different ionization sources, i.e. electrospray ionization via an elution-head based interface and also the Direct Analysis in Real Time interface, for HRMS analysis of compounds from the same class with very similar chromatographic behavior and polarity. Copyright © 2018 Elsevier B.V. All rights reserved.
Bhargava, Rhea; Janssen, William; Altmann, Christopher; Andrés-Hernando, Ana; Okamura, Kayo; Vandivier, R William; Ahuja, Nilesh; Faubel, Sarah
2013-01-01
Serum and bronchoalveolar fluid IL-6 are increased in patients with acute respiratory distress syndrome (ARDS) and predict prolonged mechanical ventilation and poor outcomes, although the role of intra-alveolar IL-6 in indirect lung injury is unknown. We investigated the role of endogenous and exogenous intra-alveolar IL-6 in AKI-mediated lung injury (indirect lung injury), intraperitoneal (IP) endotoxin administration (indirect lung injury) and, for comparison, intratracheal (IT) endotoxin administration (direct lung injury) with the hypothesis that IL-6 would exert a pro-inflammatory effect in these causes of acute lung inflammation. Bronchoalveolar cytokines (IL-6, CXCL1, TNF-α, IL-1β, and IL-10), BAL fluid neutrophils, lung inflammation (lung cytokines, MPO activity [a biochemical marker of neutrophil infiltration]), and serum cytokines were determined in adult male C57Bl/6 mice with no intervention or 4 hours after ischemic AKI (22 minutes of renal pedicle clamping), IP endotoxin (10 µg), or IT endotoxin (80 µg) with and without intratracheal (IT) IL-6 (25 ng or 200 ng) treatment. Lung inflammation was similar after AKI, IP endotoxin, and IT endotoxin. BAL fluid IL-6 was markedly increased after IT endotoxin, and not increased after AKI or IP endotoxin. Unexpectedly, IT IL-6 exerted an anti-inflammatory effect in healthy mice characterized by reduced BAL fluid cytokines. IT IL-6 also exerted an anti-inflammatory effect in IT endotoxin characterized by reduced BAL fluid cytokines and lung inflammation; IT IL-6 had no effect on lung inflammation in AKI or IP endotoxin. IL-6 exerts an anti-inflammatory effect in direct lung injury from IT endotoxin, yet has no role in the pathogenesis or treatment of indirect lung injury from AKI or IP endotoxin. Since intra-alveolar inflammation is important in the pathogenesis of direct, but not indirect, causes of lung inflammation, IT anti-inflammatory treatments may have a role in direct, but not indirect, causes of ARDS.
2008-10-22
athletes who utilize ordinary weather reports? Alpha- Thalassemia Protects Against Exertional Mortality with Sickle Cell Trait • 30% of African...Americans have alpha- thalassemia (2-3 alpha genes instead of 4). In those with sickle cell trait the main effect is to lower the Hb S fraction below 36...expected 15 cases with alpha- thalassemia & ប% S • Two cases had Hb S < 36% , implying about a 7.5-fold protection for those with alpha thalassemia
Modelling endurance and resumption times for repetitive one-hand pushing.
Rose, Linda M; Beauchemin, Catherine A A; Neumann, W Patrick
2018-07-01
This study's objective was to develop models of endurance time (ET), as a function of load level (LL), and of resumption time (RT) after loading as a function of both LL and loading time (LT) for repeated loadings. Ten male participants with experience in construction work each performed 15 different one-handed repetaed pushing tasks at shoulder height with varied exerted force and duration. These data were used to create regression models predicting ET and RT. It is concluded that power law relationships are most appropriate to use when modelling ET and RT. While the data the equations are based on are limited regarding number of participants, gender, postures, magnitude and type of exerted force, the paper suggests how this kind of modelling can be used in job design and in further research. Practitioner Summary: Adequate muscular recovery during work-shifts is important to create sustainable jobs. This paper describes mathematical modelling and presents models for endurance times and resumption times (an aspect of recovery need), based on data from an empirical study. The models can be used to help manage fatigue levels in job design.
Yoshino, Hironori; Iwabuchi, Miyu; Kazama, Yuka; Furukawa, Maho; Kashiwakura, Ikuo
2018-01-01
Retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs) are pattern-recognition receptors that recognize pathogen-associated molecular patterns and induce antiviral immune responses. Recent studies have demonstrated that RLR activation induces antitumor immunity and cytotoxicity against different types of cancer, including lung cancer. However a previous report has demonstrated that ionizing radiation exerts a limited effect on RLR in human monocytic cell-derived macrophages, suggesting that RLR agonists may be used as effective immunostimulants during radiation therapy. However, it is unclear whether ionizing radiation affects the cytotoxicity of RLR agonists against cancer cells. Therefore, in the present study the effects of cotreatment with ionizing radiation and RLR agonists on cytotoxicity against human non-small cell lung cancer cells A549 and H1299 was investigated. Treatment with RLR agonist poly(I:C)/LyoVec™ [poly(I:C)] exerted cytotoxic effects against human non-small cell lung cancer. The cytotoxic effects of poly(I:C) were enhanced by cotreatment with ionizing radiation, and poly(I:C) pretreatment resulted in the radiosensitization of non-small cell lung cancer. Furthermore, cotreatment of A549 and H1299 cells with poly(I:C) and ionizing radiation effectively induced apoptosis in a caspase-dependent manner compared with treatment with poly(I:C) or ionizing radiation alone. These results indicate that RLR agonists and ionizing radiation cotreatment effectively exert cytotoxic effects against human non-small cell lung cancer through caspase-mediated apoptosis. PMID:29541243
Li, Yan; Zhu, Zhuo R; Ou, Bao C; Wang, Ya Q; Tan, Zhou B; Deng, Chang M; Gao, Yi Y; Tang, Ming; So, Ji H; Mu, Yang L; Zhang, Lan Q
2015-02-15
Major depressive disorder is one of the most prevalent and life-threatening forms of mental illnesses. The traditional antidepressants often take several weeks, even months, to obtain clinical effects. However, recent clinical studies have shown that ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, exerts rapid antidepressant effects within 2h and are long-lasting. The aim of the present study was to investigate whether dopaminergic system was involved in the rapid antidepressant effects of ketamine. The acute administration of ketamine (20 mg/kg) significantly reduced the immobility time in the forced swim test. MK-801 (0.1 mg/kg), the more selective NMDA antagonist, also exerted rapid antidepressant-like effects. In contrast, fluoxetine (10 mg/kg) did not significantly reduced the immobility time in the forced swim test after 30 min administration. Notably, pretreatment with haloperidol (0.15 mg/kg, a nonselective dopamine D2/D3 antagonist), but not SCH23390 (0.04 and 0.1 mg/kg, a selective dopamine D1 receptor antagonist), significantly prevented the effects of ketamine or MK-801. Moreover, the administration of sub-effective dose of ketamine (10 mg/kg) in combination with pramipexole (0.3 mg/kg, a dopamine D2/D3 receptor agonist) exerted antidepressant-like effects compared with each drug alone. In conclusion, our results indicated that the dopamine D2/D3 receptors, but not D1 receptors, are involved in the rapid antidepressant-like effects of ketamine. Copyright © 2014 Elsevier B.V. All rights reserved.
Adaptive effort investment in cognitive and physical tasks: a neurocomputational model
Verguts, Tom; Vassena, Eliana; Silvetti, Massimo
2015-01-01
Despite its importance in everyday life, the computational nature of effort investment remains poorly understood. We propose an effort model obtained from optimality considerations, and a neurocomputational approximation to the optimal model. Both are couched in the framework of reinforcement learning. It is shown that choosing when or when not to exert effort can be adaptively learned, depending on rewards, costs, and task difficulty. In the neurocomputational model, the limbic loop comprising anterior cingulate cortex (ACC) and ventral striatum in the basal ganglia allocates effort to cortical stimulus-action pathways whenever this is valuable. We demonstrate that the model approximates optimality. Next, we consider two hallmark effects from the cognitive control literature, namely proportion congruency and sequential congruency effects. It is shown that the model exerts both proactive and reactive cognitive control. Then, we simulate two physical effort tasks. In line with empirical work, impairing the model's dopaminergic pathway leads to apathetic behavior. Thus, we conceptually unify the exertion of cognitive and physical effort, studied across a variety of literatures (e.g., motivation and cognitive control) and animal species. PMID:25805978
Protective effects of acerola juice on genotoxicity induced by iron in vivo
Horta, Roberta Nunes; Kahl, Vivian Francilia Silva; Sarmento, Merielen da Silva; Nunes, Marisa Fernanda Silva; Porto, Carem Rejane Maglione; de Andrade, Vanessa Moraes; Ferraz, Alexandre de Barros Falcão; Silva, Juliana Da
2016-01-01
Abstract Metal ions such as iron can induce DNA damage by inducing reactive oxygen species (ROS) and oxidative stress. Vitamin C is one of the most widely consumed antioxidants worldwide, present in many fruits and vegetables, especially inMalpighia glabra L., popularly known as acerola, native to Brazil. Acerola is considered a functional fruit due to its high antioxidant properties and phenolic contents, and therefore is consumed to prevent diseases or as adjuvant in treatment strategies. Here, the influence of ripe and unripe acerola juices on iron genotoxicity was analyzed in vivo using the comet assay and micronucleus test. The comet assay results showed that acerola juice exerted no genotoxic or antigenotoxic activity. Neither ripe nor unripe acerola juices were mutagenic to animals treated with juices, in micronucleus test. However, when compared to iron group, the pre-treatment with acerola juices exerted antimutagenic activity, decreasing significantly micronucleus mean values in bone marrow. Stage of ripeness did not influence the interaction of acerola compounds with DNA, and both ripe and unripe acerola juices exerted protective effect over DNA damage generated by iron. PMID:27007905
Negative incidental emotions augment fairness sensitivity
Liu, Cuizhen; Chai, Jing Wen; Yu, Rongjun
2016-01-01
Previous studies have shown that task-unrelated emotions induced incidentally exert carryover effects on individuals’ subsequent decisions in financial negotiations. However, the specificity of these emotion effects are not clear. In three experiments, we systematically investigated the role of seven transiently induced basic emotions (disgust, sadness, anger, fear, happiness, surprise and neutral) on rejection of unfair offers using the ultimatum game. We found that all negative emotions (disgust, sadness, anger and fear), but not happiness or surprise, significantly increased rejection rates, suggesting that the effect of incidental negative emotions on fairness is not specific to the type of negative emotion. Our findings highlight the role of fleeting emotions in biasing decision-making processes and suggest that all incidental negative emotions exert similar effects on fairness sensitivity, possibly by potentiating attention towards negative aspects of the situation. PMID:27101931
Lee, Min Jung; Park, Seung Hwan; Han, Ju Hua; Hong, Yoon Ki; Hwang, Soojin; Lee, Soojin; Kim, Darae; Han, Seung Yeop; Kim, Eun Soo; Cho, Kyoung Sang
2011-01-01
Hempseed is rich in polyunsaturated fatty acids (PUFAs), which have potential as therapeutic compounds for the treatment of neurodegenerative and cardiovascular dis-ease. However, the effect of hempseed meal (HSM) intake on the animal models of these diseases has yet to be elucidated. In this study, we assessed the effects of the intake of HSM and PUFAs on oxidative stress, cytotoxicity and neurological phenotypes, and cholesterol uptake, using Drosophila models. HSM intake was shown to reduce H2O2 toxicity markedly, indicating that HSM exerts a profound antioxidant effect. Meanwhile, intake of HSM, as well as linoleic or linolenic acids (major PUFA components of HSM) was shown to ameliorate Aβ42-induced eye degeneration, thus suggesting that these compounds exert a protective effect against Aβ42 cytotoxicity. On the contrary, locomotion and longevity in the Parkinson’s disease model andeye degeneration in the Huntington’s disease model were unaffected by HSM feeding. Additionally, intake of HSM or linoleic acid was shown to reduce cholesterol uptake significantly. Moreover, linoleic acid intake has been shown to delay pupariation, and cholesterol feeding rescued the linoleic acid-induced larval growth delay, thereby indicating that linoleic acid acts antagonistically with cholesterol during larval growth. In conclusion, our results indicate that HSM and linoleic acid exert inhibitory effects on both Aβ42 cytotoxicity and cholesterol uptake, and are potential candidates for the treatment of Alzheimer’s disease and cardiovasculardisease. PMID:21331775
Knowledge and networks – key sources of power in global health
Hanefeld, Johanna; Walt, Gill
2015-01-01
Shiffman rightly raises questions about who exercises power in global health, suggesting power is a complex concept, and the way it is exercised is often opaque. Power that is not based on financial strength but on knowledge or experience, is difficult to estimate, and yet it may provide the legitimacy to make moral claims on what is, or ought to be, on global health agendas. Twenty years ago power was exercised in a much less complex health environment. The World Health Organization (WHO) was able to exert its authority as world health leader. The landscape today is very different. Financial resources for global health are being competed for by diverse organisations, and power is diffused and somewhat hidden in such a climate, where each organization has to establish and make its own moral claims loudly and publicly. We observe two ways which allow actors to capture moral authority in global health. One, through power based on scientific knowledge and two, through procedures in the policy process, most commonly associated with the notion of broad consultation and participation. We discuss these drawing on one particular framework provided by Bourdieu, who analyses the source of actor power by focusing on different sorts of capital. Different approaches or theories to understanding power will go some way to answering the challenge Shiffman throws to health policy analysts. We need to explore much more fully where power lies in global health, and how it is exercised in order to understand underlying health agendas and claims to legitimacy made by global health actors today. PMID:25674577
Potential beneficial effects of butyrate in intestinal and extraintestinal diseases
Canani, Roberto Berni; Costanzo, Margherita Di; Leone, Ludovica; Pedata, Monica; Meli, Rosaria; Calignano, Antonio
2011-01-01
The multiple beneficial effects on human health of the short-chain fatty acid butyrate, synthesized from non-absorbed carbohydrate by colonic microbiota, are well documented. At the intestinal level, butyrate plays a regulatory role on the transepithelial fluid transport, ameliorates mucosal inflammation and oxidative status, reinforces the epithelial defense barrier, and modulates visceral sensitivity and intestinal motility. In addition, a growing number of studies have stressed the role of butyrate in the prevention and inhibition of colorectal cancer. At the extraintestinal level, butyrate exerts potentially useful effects on many conditions, including hemoglobinopathies, genetic metabolic diseases, hypercholesterolemia, insulin resistance, and ischemic stroke. The mechanisms of action of butyrate are different; many of these are related to its potent regulatory effects on gene expression. These data suggest a wide spectrum of positive effects exerted by butyrate, with a high potential for a therapeutic use in human medicine. PMID:21472114
Suyama, Shigetomo; Maekawa, Fumihiko; Maejima, Yuko; Kubota, Naoto; Kadowaki, Takashi; Yada, Toshihiko
2016-08-09
Adiponectin regulates glucose and lipid metabolism, acting against metabolic syndrome and atherosclerosis. Accumulating evidence suggest that adiponectin acts on the brain including hypothalamic arcuate nucleus (ARC), where proopiomelanocortin (POMC) neurons play key roles in feeding regulation. Several studies have examined intracerebroventricular (ICV) injection of adiponectin and reported opposite effects, increase or decrease of food intake. These reports used different nutritional states. The present study aimed to clarify whether adiponectin exerts distinct effects on food intake and ARC POMC neurons depending on the glucose concentration. Adiponectin was ICV injected with or without glucose for feeding experiments and administered to ARC slices with high or low glucose for patch clamp experiments. We found that adiponectin at high glucose inhibited POMC neurons and increased food intake while at low glucose it exerted opposite effects. The results demonstrate that glucose level determines excitatory or inhibitory effects of adiponectin on arcuate POMC neuron activity and feeding.
Oral contraceptives and mood in women with and without premenstrual dysphoria: a theoretical model.
Kurshan, N; Neill Epperson, C
2006-01-01
Despite numerous studies on the topic, there is no consensus to date on the effects of oral contraceptives on mood or the mechanism(s) by which they exert these effects. This review article presents a theoretical model to explain the way in which oral contraceptives may affect mood. Specifically, it is argued that progestins exert differential effects on endogenous levels of neurosteroids, thereby altering mood. After providing an overview of the effects of estrogen, progesterone, and progesterone's metabolites on cortical excitability and the role of neurosteroids in depression and premenstrual dysphoria, this article reviews the research that has been conducted on the relationship between oral contraceptives and neurosteroids. Finally, suggestions for future research are made with the dual aim of improving existing studies on the relationship between oral contraceptives and mood and further investigating the possibility that fluctuations in neurosteroid levels are responsible for the effects of oral contraceptives on mood.
Rest Interval Required for Power Training With Power Load in the Bench Press Throw Exercise.
Hernández Davó, Jose L; Solana, Rafael Sabido; Sarabia Marín, Jose M; Fernández Fernández, Jaime; Moya Ramón, Manuel
2016-05-01
This study aimed to test the influence of various rest interval (RI) durations used between sets on power output performance and physiological and perceptual variables during a strength training session using 40% of the 1 repetition maximum (1RM) in the bench press throw exercise. Thirty-one college students (18 males and 13 females) took part in the study. The experimental protocol consists of 5 sets of 8 repetitions of the bench press throw exercise with a load representing 40% of 1RM. Subjects performed the experimental protocol on 3 different occasions, differing by the RI between sets (1, 2, or 3 minutes). During the sessions, power data (mean power and peak power), physiological (lactate concentration [La]) and perceptual (rating of perceived exertion) variables were measured. In addition, delayed onset muscular soreness was reported 24 and 48 hours after the training session. One-way repeated-measures analysis of variance showed that 1-minute RI entailed higher power decreases and greater increases in values of physiological and perceptual variables compared with both 2- and 3-minute RIs. Nevertheless, no differences were found between 2- and 3-minute RIs. Therefore, this study showed that, when training with 40% of 1RM in the bench press throw exercise, a 2-minute RI between sets can be enough to avoid significant decreases in power output. Consequently, training sessions' duration could be reduced without causing excessive fatigue, allowing additional time to focus on other conditioning priorities.
Hajkova, Michaela; Hermankova, Barbora; Javorkova, Eliska; Bohacova, Pavla; Zajicova, Alena; Holan, Vladimir; Krulova, Magdalena
2017-02-01
Immunosuppressive drugs are widely used to treat undesirable immune reaction, however their clinical use is often limited by harmful side effects. The combined application of immunosuppressive agents with mesenchymal stem cells (MSCs) offers a promising alternative approach that enables the reduction of immunosuppressive agent doses and simultaneously maintains or improves the outcome of therapy. The present study aimed to determinate the effects of immunosuppressants on individual T cell subpopulations and to investigate the efficacy of MSC-based treatment combined with immunosuppressive drugs. We tested the effect of five widely used immunosuppressants with different action mechanisms: cyclosporine A, mycophenolate mofetil, rapamycin, and two glucocorticoids - prednisone and dexamethasone in combination with MSCs on mouse CD4 + and CD8 + lymphocyte viability and activation, Th17 (RORγt + ), Th1 (T-bet + ), Th2 (GATA-3 + ) and Treg (Foxp3 + ) cell proportion and on the production of corresponding key cytokines (IL-17, IFNγ, IL-4 and IL-10). We showed that MSCs modulate the actions of immunosuppressants and in combination with immunosuppressive drugs display distinct effect on cell activation and balance among different T lymphocytes subpopulations and exert a suppressive effect on proinflammatory T cell subsets while promoting the functions of anti-inflammatory Treg lymphocytes. The results indicated that MSC-based therapy could be a powerful strategy to attenuate the negative effects of immunosuppressive drugs on the immune system.
Metoprolol vs ivabradine in patients with mitral stenosis in sinus rhythm.
Agrawal, Vikas; Kumar, Niraj; Lohiya, Balalji; Sihag, Bhupendra K; Prajapati, Rajpal; Singh, T B; Subramanian, Geetha
2016-10-15
Severe mitral stenosis is usually symptomatic and is treated by BMV or surgery, whereas mild to moderate mitral stenosis is usually asymptomatic or mildly symptomatic and managed medically. Patients in the later group may become symptomatic during episodes of exercise and increased heart rate. Beta-blockers are frequently used in patients with mitral stenosis to control the heart rate and alleviate exercise-related symptoms. The objective of our study was to investigate the comparative efficacy of ivabradine versus metoprolol in patients with mitral stenosis in sinus rhythm. We studied 97 patients of mitral stenosis in sinus rhythm presented with exertional symptoms. The effectiveness of Metoprolol was compared with ivabradine in alleviating these exertional symptoms in a randomized, open label non crossover study. We also assessed various stress ECG parameters, 24 hour Holter parameters and 2D Echo parameters to objectively compare the effects of ivabradine and metoprolol in these patients. Ivabradine and metoprolol both were effective in controlling exertional symptoms. Significant improvement in objective parameters like TMT (work capacity, baseline heart rate and maximal heart rate) and 2D echocardiography (right ventricular systolic pressure) are seen with both drugs. Ivabradine controls the exertional symptoms significantly more than metoprolol. On head to head comparison there was a significant benefit of working capacity and heart rate at maximal exercise in favour of ivabradine. Ivabradine should be strongly considered in medical management of mitral stenosis patients where beta blockers are contraindicated such as reactive airway disease. The cost of ivabradine is higher than metoprolol which might possess constraints as most of the rheumatic heat disease patients belong to low socio economic status. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Pressure effects on the nose by an in-flight oxygen mask during simulated flight conditions.
Schreinemakers, J Rieneke C; Boer, C; van Amerongen, P C G M; Kon, M
2016-12-01
Dutch F-16 fighter pilots experience oxygen mask inflicted nasal trauma, including discomfort, pain, skin abrasions, bruises and bone remodelling. Pressure and shear forces on the nose might contribute to causing these adverse effects. In this study, it was evaluated how flight conditions affected the exerted pressure, and whether shear forces were present. The pressure exerted by the oxygen mask was measured in 20 volunteers by placing pressure sensors on the nose and chin underneath the mask. In the human centrifuge, the effects on the exerted pressure during different flight conditions were evaluated (+3G z , +6G z , +9G z , protocolised head movements, mounted visor or night vision goggles, NVG). The runs were recorded to evaluate if the mask's position changed during the run, which would confirm the presence of shear forces. Head movements increased the median pressure on the nose by 50 mm Hg and on the chin by 37 mm Hg. NVG, a visor and accelerative forces also increased the median pressure on the nose. Pressure drops on the nose were also observed, during mounted NVG (-63 mm Hg). The recordings showed the mask slid downwards, especially during the acceleration phase of the centrifuge run, signifying the presence of shear forces. The exerted pressure by the oxygen mask changes during different flight conditions. Exposure to changing pressures and to shear forces probably contributes to mask-inflicted nasal trauma. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Novel Investigations of Flavonoids as Chemopreventive Agents for Hepatocellular Carcinoma
Liao, Chen-Yi; Lee, Ching-Chang; Tsai, Chi-chang; Hsueh, Chao-Wen; Wang, Chih-Chiang; Chen, I-Hung; Tsai, Ming-Kai; Liu, Mei-Yu; Hsieh, An-Tie; Su, Kuan-Jen; Wu, Hau-Ming; Huang, Shih-Chung; Wang, Yi-Chen; Wang, Chien-Yao; Huang, Shu-Fang; Yeh, Yen-Cheng; Ben, Ren-Jy; Chien, Shang-Tao; Hsu, Chin-Wen; Kuo, Wu-Hsien
2015-01-01
We would like to highlight the application of natural products to hepatocellular carcinoma (HCC). We will focus on the natural products known as flavonoids, which target this disease at different stages of hepatocarcinogenesis. In spite of the use of chemotherapy and radiotherapy in treating HCC, patients with HCC still face poor prognosis because of the nature of multidrug resistance and toxicity derived from chemotherapy and radiotherapy. Flavonoids can be found in many vegetables, fruits, and herbal medicines that exert their different anticancer effects via different intracellular signaling pathways and serve as antioxidants. In this review, we will discuss seven common flavonoids that exert different biological effects against HCC via different pathways. PMID:26858957
DOE Office of Scientific and Technical Information (OSTI.GOV)
Feng, Li-Li; Wu, Xue-Feng; Liu, Hai-Liang
2013-03-01
In the present study, we aimed to investigate the immunosuppressive activity of vaticaffinol, a resveratrol tetramer isolated from Vatica mangachapoi, on T lymphocytes both in vitro and in vivo, and further explored its potential molecular mechanism. Resveratrol had a wide spectrum of healthy beneficial effects with multiple targets. Interestingly, its tetramer, vaticaffinol, exerted more intensive immunosuppressive activity than resveratrol. Vaticaffinol significantly inhibited T cells proliferation activated by concanavalin A (Con A) or anti-CD3 plus anti-CD28 in a dose- and time-dependent manner. It also induced Con A-activated T cells undergoing apoptosis through mitochondrial pathway. Moreover, this compound prevented cells from enteringmore » S phase and G2/M phase during T cells activation. In addition, vaticaffinol inhibited ERK and AKT signaling pathways in Con A-activated T cells. Furthermore, vaticaffinol significantly ameliorated ear swelling in a mouse model of picryl chloride-induced ear contact dermatitis in vivo. In most of the aforementioned experiments, however, resveratrol had only slight effects on the inhibition of T lymphocytes compared with vaticaffinol. Taken together, our findings suggest that vaticaffinol exerts more preferable immunosuppressive activity than its precursor resveratrol both in vitro and in vivo by affecting multiple targets against activated T cells. - Graphical abstract: Vaticaffinol, a resveratrol tetramer isolated from Vatica mangachapoi, exerts more intensive immunosuppressive activity than its precursor resveratrol does in vitro and in vivo. Its mechanism may involve multiple effects against activated T cells: regulation of signalings involved in cell proliferation, G0/G1 arrest of T cells, as well as an apoptosis induction in activated effector T cells. Highlights: ► Vaticaffinol, a resveratrol tetramer, exerts more potent activity than its precursor. ► It inhibited T cells proliferation and prevented them from entering cell cycles. ► It led to apoptosis of activated T cells through mitochondrial pathway. ► It down-regulated ERK and AKT signaling pathways in Con A-activated T cells. ► It significantly ameliorated picryl chloride-induced ear swelling.« less
Flouris, A D; Friesen, B J; Carlson, M J; Casa, D J; Kenny, G P
2015-06-01
Immediate treatment with cold water immersion (CWI) is the gold standard for exertional heatstroke. In the field, however, treatment is often delayed due to delayed paramedic response and/or inaccurate diagnosis. We examined the effect of treatment (reduction of rectal temperature to 37.5 °C) delays of 5, 20, and 40 min on core cooling rates in eight exertionally heat-stressed (40.0 °C rectal temperature) individuals. We found that rectal temperature was elevated above baseline (P < 0.05) at the end of all delay periods (5 min: 40.08 ± 0.32; 20 min: 39.92 ± 0.40; 40 min: 39.57 ± 0.29 °C). Mean arterial pressure was reduced (P < 0.05) below baseline (92 ± 1.8 mm Hg) after all delay periods (5 min: 75 ± 2.6; 20 min: 74 ± 1.7; 40 min: 70 ± 2.1 mm Hg; P > 0.05). Rectal core cooling rates were similar among conditions (5 min: 0.20 ± 0.01; 20 min: 0.17 ± 0.02; 40 min: 0.17 ± 0.01 °C/min; P > 0.05). The rectal temperature afterdrop following CWI was similar across conditions (5 min: 35.95; 20 min: 35.61; 40 min: 35.87 °C; P > 0.05). We conclude that the effectiveness of 2 °C CWI as a treatment for exertional heat stress remains high even when applied with a delay of 40 min. Therefore, our results support that CWI is the most appropriate treatment for exertional heatstroke as it is capable of quickly reversing hyperthermia even when treatment is commenced with a significant delay. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Individual differences in dopamine level modulate the ego depletion effect.
Dang, Junhua; Xiao, Shanshan; Liu, Ying; Jiang, Yumeng; Mao, Lihua
2016-01-01
Initial exertion of self-control impairs subsequent self-regulatory performance, which is referred to as the ego depletion effect. The current study examined how individual differences in dopamine level, as indexed by eye blink rate (EBR), would moderate ego depletion. An inverted-U-shaped relationship between EBR and subsequent self-regulatory performance was found when participants initially engaged in self-control but such relationship was absent in the control condition where there was no initial exertion, suggesting individuals with a medium dopamine level may be protected from the typical ego depletion effect. These findings are consistent with a cognitive explanation which considers ego depletion as a phenomenon similar to "switch costs" that would be neutralized by factors promoting flexible switching. Copyright © 2015 Elsevier B.V. All rights reserved.
Novel Interventions for Heat/Exercise Induced Sudden Death and Fatigue
2013-10-01
mutations associated with enhanced susceptibility to Exertional Heat Stroke (EHS), Exertional Rhabdomyolysis (ER), and Malignant Hyperthermia (MH) by...reduces the probability of a hypermetabolic response in YS mice. 15. SUBJECT TERMS: Exertional Heat Stroke, Exertional Rhabdomyolysis ...and exertional rhabdomyolysis (ER) have been reported in subjects with diagnosis of Malignant Hyperthermia (MH). MH is a life- threatening
Codella, Roberto; Ialacqua, Marta; Terruzzi, Ileana; Luzi, Livio
2018-05-05
Physical activity, together with diet and pharmacological therapy, represents one of the three cornerstones in type 2 diabetes mellitus treatment and care. The therapeutic appeal of regular physical activity stems from: (i) its non-pharmacological nature; (ii) its beneficial effects on the metabolic risk factors associated with diabetes complications; (iii) its low costs. Evidence accumulated in the last years suggests that aerobic training-endurance training-constitutes a safe modality of intervention, achievable, and effective in diabetes treatment, whenever it is not limited by comorbidities. Aerobic training exerts insulin-mimetic effects and has been shown to lower mortality risk too. Anaerobic, intense physical activity, such as that of strength or power sports disciplines, is not univocally recognized as safe and simple to realize, however, it is important in stimulating energy and glucose metabolism. According to recent evidence, high-intensity training may be prescribed even in the face of cardiovascular diseases, peripheral vascular disease, or osteoarthritis. Some studies have shown resistance training to be more efficient than aerobic exercise in improving glycemic control. This review explores the most up-to-date indications emerging from literature in support of the beneficial effects of strength stimulation and resistance training in patients with type 2 diabetes without complications.
Media coverage of "wise" interventions can reduce concern for the disadvantaged.
Ikizer, Elif G; Blanton, Hart
2016-06-01
Recent articulation of the "wise" approach to psychological intervention has drawn attention to the way small, seemingly trivial social psychological interventions can exert powerful, long-term effects. These interventions have been used to address such wide-ranging social issues as the racial achievement gap, environmental conservation, and the promotion of safer sex. Although there certainly are good reasons to seek easier as opposed to harder solutions to social problems, we examine a potentially undesirable effect that can result from common media portrayals of wise interventions. By emphasizing the ease with which interventions help address complex social problems, media reports might decrease sympathy for the individuals assisted by such efforts. Three studies provide evidence for this, showing that media coverage of wise interventions designed to address academic and health disparities increased endorsement of the view that the disadvantaged can solve their problems on their own, and the tendency to blame such individuals for their circumstances. Effects were strongest for interventions targeted at members of a historically disadvantaged group (African Americans as opposed to college students) and when the coverage was read by conservatives as opposed to liberals. Attempts to undermine this effect by introducing cautious language had mixed success. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
The control of mono-articular muscles in multijoint leg extensions in man.
van Ingen Schenau, G J; Dorssers, W M; Welter, T G; Beelen, A; de Groot, G; Jacobs, R
1995-01-01
1. Movements often require control of direction and a magnitude of force exerted externally on the environment. Bi-articular upper leg muscles appear to play a unique role in the regulation of the net torques about the hip and knee joints, necessary for the control of this external force. 2. The aim of this study was to test the hypothesis that the mono-articular muscles act as work generators in powerful dynamic leg extensions, which means that they should be activated primarily in the phases during which they can contribute to work, irrespective of the net joint torques required to control the external force. 3. Cycling movements of six trained subjects were analysed by means of inverse dynamics, yielding net joint torques as well as activity patterns and shortening velocities of four mono- and four bi-articular leg muscles. 4. The results show that the mono-articular muscles exert force only in the phase in which these muscles shorten, whereas this appears not to be the case for the bi-articular muscles. 5. Reciprocal patterns of activation of the rectus femoris and hamstring muscles appear to tune the distribution of net joint torques about the hip and knee joints, necessary to control the (changing) direction of the force on the pedal. 6. An analysis of running in man and additional related literature based on animal studies appears to provide further support for the hypothesis that mono- and bi-articular muscles have essentially different roles in these powerful multijoint leg extension tasks. PMID:7602524
Ruan, Ling; Han, Ge; Zhu, Zhongmin; Zhang, Miao; Gong, Wei
2015-01-01
The accurate estimation of deposits adhering on insulators is of great significance to prevent pollution flashovers which cause huge costs worldwide. Researchers have developed sensors using different technologies to monitor insulator contamination on a fine time scale. However, there is lack of analysis of these data to reveal spatial and temporal characteristics of insulator contamination, and as a result the scheduling of periodical maintenance of power facilities is highly dependent on personal experience. Owing to the deployment of novel sensors, daily Equivalent Salt Deposit Density (ESDD) observations of over two years were collected and analyzed for the first time. Results from 16 sites distributed in four regions of Hubei demonstrated that spatial heterogeneity can be seen at both the fine and coarse geographical scales, suggesting that current polluted area maps are necessary but are not sufficient conditions to guide the maintenance of power facilities. Both the local emission and the regional air pollution condition exert evident influences on deposit accumulation. A relationship between ESDD and PM10 was revealed by using regression analysis, proving that air pollution exerts influence on pollution accumulations on insulators. Moreover, the seasonality of ESDD was discovered for the first time by means of time series analysis, which could help engineers select appropriate times to clean the contamination. Besides, the trend component shows that the ESDD increases in a negative exponential fashion with the accumulation date (ESDD = a − b × exp(−time)) at a long time scale in real environments. PMID:25643058
Kao, Huei Chu; Lin, Chiuhsiang Joe; Lee, Yung Hui; Chen, Su Huang
2015-01-01
The purpose of this study was to explore the effects of direction of exertion (DOE) (pushing, pulling), path (walking in a straight line, turning left, walking uphill), and load placement (LP) (the 18 blocks were indicated by X, Y and Z axis; there were 3 levels on the X axis, 2 levels on the Y axis, and 3 levels on the Z axis) on muscle activity and ratings of perceived exertion in nursing cart pushing and pulling tasks. Ten participants who were female students and not experienced nurses were recruited to participate in the experiment. Each participant performed 108 experimental trials in the study, consisting of 2 directions of exertion (push and pull), 3 paths, and 18 load placements (indicated by X, Y and Z axes). A 23kg load was placed into one load placement. The dependent variables were electromyographic (EMG) data of four muscles collected bilaterally as follows: Left (L) and right (R) trapezius (TR), flexor digitorum superficialis (FDS), extensor digitorum (ED), and erector spinae (ES) and subjective ratings of perceived exertion (RPE). Split-split-plot ANOVA was conducted to analyze significant differences between DOE, path, and LP in the EMG and RPE data. Pulling cart tasks produced a significantly higher activation of the muscles (RTR:54.4%, LTR:50.3%, LFDS:57.0%, LED:63.4%, RES:40.7%, LES:36.7%) than pushing cart tasks (RTR:42.4%, LTR:35.1%, LFDS:32.3%, LED:55.1%, RES:33.3%, LES:32.1%). A significantly greater perceived exertion was found in pulling cart tasks than pushing cart tasks. Significantly higher activation of all muscles and perceived exertion were observed for walking uphill than walking in a straight line and turning left. Significantly lower muscle activity of all muscles and subject ratings were observed for the central position on the X axis, the bottom position on the Y axis, and the posterior position on the Z axis. These findings suggest that nursing staff should adopt forward pushing when moving a nursing cart, instead of backward pulling, and that uphill paths should be avoided in the design of work environments. In terms of distribution of the load in a nursing cart, heavier materials should be positioned at bottom of the cabinet, centered on the horizontal plane and close to the handle, to reduce the physical load of the nursing staff.