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Hydraulic geometry of the Platte River in south-central Nebraska

USGS Publications Warehouse

Eschner, T.R.

1982-01-01

At-a-station hydraulic-geometry of the Platte River in south-central Nebraska is complex. The range of exponents of simple power-function relations is large, both between different reaches of the river, and among different sections within a given reach. The at-a-station exponents plot in several fields of the b-f-m diagram, suggesting that morphologic and hydraulic changes with increasing discharge vary considerably. Systematic changes in the plotting positions of the exponents with time indicate that in general, the width exponent has decreased, although trends are not readily apparent in the other exponents. Plots of the hydraulic-geometry relations indicate that simple power functions are not the proper model in all instances. For these sections, breaks in the slopes of the hydraulic geometry relations serve to partition the data sets. Power functions fit separately to the partitioned data described the width-, depth-, and velocity-discharge relations more accurately than did a single power function. Plotting positions of the exponents from hydraulic geometry relations of partitioned data sets on b-f-m diagrams indicate that much of the apparent variations of plotting positions of single power functions results because the single power functions compromise both subsets of partitioned data. For several sections, the shape of the channel primarily accounts for the better fit of two-power functions to partitioned data than a single power function over the entire range of data. These non-log linear relations may have significance for channel maintenance. (USGS)
Neural correlates of social motivation: an fMRI study on power versus affiliation.

PubMed

Quirin, Markus; Meyer, Frank; Heise, Nils; Kuhl, Julius; Küstermann, Ekkehard; Strüber, Daniel; Cacioppo, John T

2013-06-01

Power versus affiliation motivations refer to two different strivings relevant in the context of social relationships. We used functional magnetic resonance imaging (fMRI) to determine neural structures involved in power versus affiliation motivation based on an individual differences approach. Seventeen participants provided self-reports of power and affiliation motives and were presented with love, power-related, and control movie clips. The power motive predicted activity in four clusters within the left prefrontal cortex (PFC), while participants viewed power-related film clips. The affiliation motive predicted activity in the right putamen/pallidum while participants viewed love stories. The present findings extend previous research on social motivations to the level of neural functioning and suggest differential networks for power-related versus affiliation-related social motivations. Copyright © 2012 Elsevier B.V. All rights reserved.
Gamma power and cognition in patients with schizophrenia and their first-degree relatives.

PubMed

Díez, Álvaro; Suazo, Vanessa; Casado, Pilar; Martín-Loeches, Manuel; Molina, Vicente

2014-01-01

Gamma oscillations are essential for functional neural assembly formation underlying higher cerebral functions. Previous studies concerning gamma band power in schizophrenia have yielded diverse results. In this study, we assessed gamma band power in minimally treated patients with schizophrenia, their first-degree relatives and healthy controls during an oddball paradigm performance, as well as the relation between gamma power and cognitive performance. We found a higher gamma power in the patient group than in the healthy controls at the P3, P4, Fz, Pz and T5 sites. Compared with their relatives, gamma power in the patients was only marginally higher over P3 and P4. We found a nearly significant inverse association between gamma power at F4 and Tower of London performance in the patients, as well as a significant inverse association between gamma power at T5 and verbal memory and working memory scores in the relatives. These results support higher total gamma power in association with schizophrenia and its inverse association with cognitive performance in patients and their first-degree relatives.
Mismatch negativity is a stronger indicator of functional outcomes than neurocognition or theory of mind in patients with schizophrenia.

PubMed

Lee, Seung-Hwan; Sung, Kyongae; Lee, Kyong-Sang; Moon, Eunok; Kim, Chang-Gyu

2014-01-03

Mismatch negativity (MMN) is known to be associated with neurocognition, social cognition, and functional outcomes. The present study explored the relationships of MMN with neurocognition, theory of mind, and functional outcomes in patients with schizophrenia, first-degree relatives of patients with schizophrenia, and healthy controls. Twenty-five patients with schizophrenia, 21 first-degree relatives of patients with schizophrenia, and 29 healthy controls were recruited. We examined symptom severity, neurocognition, theory of mind, functional outcomes, and MMN. MMN amplitudes decreased in order of patients with schizophrenia, then first-degree relatives, then healthy controls. MMN amplitude was significantly correlated with measures of neurocognition, theory of mind, and functional outcome measurements in patients with schizophrenia. However, the most powerful correlations were those between MMN in the frontal region and measures of functional outcomes. The power and frequency of the correlations were weaker in first-degree relatives and healthy controls than in patients with schizophrenia. Hierarchical regression analysis revealed that functional outcomes (relative to measures of neurocognition and theory of mind) constituted the most powerful predictor of MMN. Our results suggest that MMN reflects functional outcomes more efficiently than do measures of neurocognition and theory of mind in patients with schizophrenia. © 2013.
Accelerated Testing and Modeling of Potential-Induced Degradation as a Function of Temperature and Relative Humidity

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

Hacke, Peter; Spataru, Sergiu; Terwilliger, Kent

2015-06-14

An acceleration model based on the Peck equation was applied to power performance of crystalline silicon cell modules as a function of time and of temperature and humidity, the two main environmental stress factors that promote potential-induced degradation. This model was derived from module power degradation data obtained semi-continuously and statistically by in-situ dark current-voltage measurements in an environmental chamber. The modeling enables prediction of degradation rates and times as functions of temperature and humidity. Power degradation could be modeled linearly as a function of time to the second power; additionally, we found that coulombs transferred from the active cellmore » circuit to ground during the stress test is approximately linear with time. Therefore, the power loss could be linearized as a function of coulombs squared. With this result, we observed that when the module face was completely grounded with a condensed phase conductor, leakage current exceeded the anticipated corresponding degradation rate relative to the other tests performed in damp heat.« less
Power and Roots by Recursion.

ERIC Educational Resources Information Center

Aieta, Joseph F.

1987-01-01

This article illustrates how questions from elementary finance can serve as motivation for studying high order powers, roots, and exponential functions using Logo procedures. A second discussion addresses a relatively unknown algorithm for the trigonometric exponential and hyperbolic functions. (PK)
Primordial black holes and uncertainties in the choice of the window function

NASA Astrophysics Data System (ADS)

Ando, Kenta; Inomata, Keisuke; Kawasaki, Masahiro

2018-05-01

Primordial black holes (PBHs) can be produced by the perturbations that exit the horizon during the inflationary phase. While inflation models predict the power spectrum of the perturbations in Fourier space, the PBH abundance depends on the probability distribution function of density perturbations in real space. To estimate the PBH abundance in a given inflation model, we must relate the power spectrum in Fourier space to the probability density function in real space by coarse graining the perturbations with a window function. However, there are uncertainties on what window function should be used, which could change the relation between the PBH abundance and the power spectrum. This is particularly important in considering PBHs with mass 30 M⊙, which account for the LIGO events because the required power spectrum is severely constrained by the observations. In this paper, we investigate how large an influence the uncertainties on the choice of a window function has over the power spectrum required for LIGO PBHs. As a result, it is found that the uncertainties significantly affect the prediction for the stochastic gravitational waves induced by the second-order effect of the perturbations. In particular, the pulsar timing array constraints on the produced gravitational waves could disappear for the real-space top-hat window function.
Determination of Strength Exercise Intensities Based on the Load-Power-Velocity Relationship

PubMed Central

Jandačka, Daniel; Beremlijski, Petr

2011-01-01

The velocity of movement and applied load affect the production of mechanical power output and subsequently the extent of the adaptation stimulus in strength exercises. We do not know of any known function describing the relationship of power and velocity and load in the bench press exercise. The objective of the study is to find a function modeling of the relationship of relative velocity, relative load and mechanical power output for the bench press exercise and to determine the intensity zones of the exercise for specifically focused strength training of soccer players. Fifteen highly trained soccer players at the start of a competition period were studied. The subjects of study performed bench presses with the load of 0, 10, 30, 50, 70 and 90% of the predetermined one repetition maximum with maximum possible speed of movement. The mean measured power and velocity for each load (kg) were used to develop a multiple linear regression function which describes the quadratic relationship between the ratio of power (W) to maximum power (W) and the ratios of the load (kg) to one repetition maximum (kg) and the velocity (m•s−1) to maximal velocity (m•s−1). The quadratic function of two variables that modeled the searched relationship explained 74% of measured values in the acceleration phase and 75% of measured values from the entire extent of the positive power movement in the lift. The optimal load for reaching maximum power output suitable for the dynamics effort strength training was 40% of one repetition maximum, while the optimal mean velocity would be 75% of maximal velocity. Moreover, four zones: maximum power, maximum velocity, velocity-power and strength-power were determined on the basis of the regression function. PMID:23486484
Determination of strength exercise intensities based on the load-power-velocity relationship.

PubMed

Jandačka, Daniel; Beremlijski, Petr

2011-06-01

The velocity of movement and applied load affect the production of mechanical power output and subsequently the extent of the adaptation stimulus in strength exercises. We do not know of any known function describing the relationship of power and velocity and load in the bench press exercise. The objective of the study is to find a function modeling of the relationship of relative velocity, relative load and mechanical power output for the bench press exercise and to determine the intensity zones of the exercise for specifically focused strength training of soccer players. Fifteen highly trained soccer players at the start of a competition period were studied. The subjects of study performed bench presses with the load of 0, 10, 30, 50, 70 and 90% of the predetermined one repetition maximum with maximum possible speed of movement. The mean measured power and velocity for each load (kg) were used to develop a multiple linear regression function which describes the quadratic relationship between the ratio of power (W) to maximum power (W) and the ratios of the load (kg) to one repetition maximum (kg) and the velocity (m•s(-1)) to maximal velocity (m•s(-1)). The quadratic function of two variables that modeled the searched relationship explained 74% of measured values in the acceleration phase and 75% of measured values from the entire extent of the positive power movement in the lift. The optimal load for reaching maximum power output suitable for the dynamics effort strength training was 40% of one repetition maximum, while the optimal mean velocity would be 75% of maximal velocity. Moreover, four zones: maximum power, maximum velocity, velocity-power and strength-power were determined on the basis of the regression function.
Role of information theoretic uncertainty relations in quantum theory

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

Jizba, Petr, E-mail: p.jizba@fjfi.cvut.cz; ITP, Freie Universität Berlin, Arnimallee 14, D-14195 Berlin; Dunningham, Jacob A., E-mail: J.Dunningham@sussex.ac.uk

2015-04-15

Uncertainty relations based on information theory for both discrete and continuous distribution functions are briefly reviewed. We extend these results to account for (differential) Rényi entropy and its related entropy power. This allows us to find a new class of information-theoretic uncertainty relations (ITURs). The potency of such uncertainty relations in quantum mechanics is illustrated with a simple two-energy-level model where they outperform both the usual Robertson–Schrödinger uncertainty relation and Shannon entropy based uncertainty relation. In the continuous case the ensuing entropy power uncertainty relations are discussed in the context of heavy tailed wave functions and Schrödinger cat states. Again,more » improvement over both the Robertson–Schrödinger uncertainty principle and Shannon ITUR is demonstrated in these cases. Further salient issues such as the proof of a generalized entropy power inequality and a geometric picture of information-theoretic uncertainty relations are also discussed.« less
The far side: the meta functions of humanitarianism in a globalised world.

PubMed

Donini, Antonio

2010-04-01

This paper explores the meta functions of humanitarianism--that is, the functions that, as an ideology, a movement and a profession, it performs, wittingly or unwittingly, in the early twenty-first century. The term humanitarianism is used as shorthand to encompass a complex set of currents of thought, actions and institutions of which the boundaries are unclear. The focus is on mainstream humanitarianism, the dominant Northern/Western enterprise. The paper first discusses the relationship between humanitarianism and globalised power. It goes on to examine three types of functions that humanitarianism and humanitarian action perform: 'macro' functions--the deep undercurrents, power relations and values that humanitarianism articulates and transmits; 'meso' functions--those that relate to the political economy of humanitarian action and to the mechanics (rather than to the ideology) of globalisation; and 'micro' functions that relate to the motivations of the individuals who devote their energies to humanitarianism.
Multiple scattering corrections to the Beer-Lambert law. 2: Detector with a variable field of view.

PubMed

Zardecki, A; Tam, W G

1982-07-01

The multiple scattering corrections to the Beer-Lambert law in the case of a detector with a variable field of view are analyzed. We introduce transmission functions relating the received radiant power to reference power levels relevant to two different experimental situations. In the first case, the transmission function relates the received power to a reference power level appropriate to a nonattenuating medium. In the second case, the reference power level is established by bringing the receiver to the close-up position with respect to the source. To examine the effect of the variation of the detector field of view the behavior of the gain factor is studied. Numerical results modeling the laser beam propagation in fog, cloud, and rain are presented.
High frequency x-ray generator basics.

PubMed

Sobol, Wlad T

2002-02-01

The purpose of this paper is to present basic functional principles of high frequency x-ray generators. The emphasis is put on physical concepts that determine the engineering solutions to the problem of efficient generation and control of high voltage power required to drive the x-ray tube. The physics of magnetically coupled circuits is discussed first, as a background for the discussion of engineering issues related to high-frequency power transformer design. Attention is paid to physical processes that influence such factors as size, efficiency, and reliability of a high voltage power transformer. The basic electrical circuit of a high frequency generator is analyzed next, with focus on functional principles. This section investigates the role and function of basic components, such as power supply, inverter, and voltage doubler. Essential electronic circuits of generator control are then examined, including regulation of voltage, current and timing of electrical power delivery to the x-ray tube. Finally, issues related to efficient feedback control, including basic design of the AEC circuitry are reviewed.
Alternative Proofs for Inequalities of Some Trigonometric Functions

ERIC Educational Resources Information Center

Guo, Bai-Ni; Qi, Feng

2008-01-01

By using an identity relating to Bernoulli's numbers and power series expansions of cotangent function and logarithms of functions involving sine function, cosine function and tangent function, four inequalities involving cotangent function, sine function, secant function and tangent function are established.
78 FR 33689 - Organization and Delegation of Powers and Duties

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-05

... 0311-AA02 Organization and Delegation of Powers and Duties AGENCY: Privacy and Civil Liberties... this rule to provide information to the public about the Board's organization, function, and operations...'s organization and functioning and, therefore, is exempt from requirements related to notice and...
Power function decay of hydraulic conductivity for a TOPMODEL-based infiltration routine

NASA Astrophysics Data System (ADS)

Wang, Jun; Endreny, Theodore A.; Hassett, James M.

2006-11-01

TOPMODEL rainfall-runoff hydrologic concepts are based on soil saturation processes, where soil controls on hydrograph recession have been represented by linear, exponential, and power function decay with soil depth. Although these decay formulations have been incorporated into baseflow decay and topographic index computations, only the linear and exponential forms have been incorporated into infiltration subroutines. This study develops a power function formulation of the Green and Ampt infiltration equation for the case where the power n = 1 and 2. This new function was created to represent field measurements in the New York City, USA, Ward Pound Ridge drinking water supply area, and provide support for similar sites reported by other researchers. Derivation of the power-function-based Green and Ampt model begins with the Green and Ampt formulation used by Beven in deriving an exponential decay model. Differences between the linear, exponential, and power function infiltration scenarios are sensitive to the relative difference between rainfall rates and hydraulic conductivity. Using a low-frequency 30 min design storm with 4.8 cm h-1 rain, the n = 2 power function formulation allows for a faster decay of infiltration and more rapid generation of runoff. Infiltration excess runoff is rare in most forested watersheds, and advantages of the power function infiltration routine may primarily include replication of field-observed processes in urbanized areas and numerical consistency with power function decay of baseflow and topographic index distributions. Equation development is presented within a TOPMODEL-based Ward Pound Ridge rainfall-runoff simulation. Copyright
Design of a power-asymmetric actuator for a transtibial prosthesis.

PubMed

Bartlett, Harrison L; Lawson, Brian E; Goldfarb, Michael

2017-07-01

This paper presents the design and characterization of a power-asymmetric actuator for a transtibial prosthesis. The device is designed to provide the combination of: 1) joint locking, 2) high power dissipation, and 3) low power generation. This actuator functionality allows for a prosthesis to be designed with minimal mass and power consumption relative to a fully-powered robotic prosthesis while maintaining much of the functionality necessary for activities of daily living. The actuator achieves these design characteristics while maintaining a small form factor by leveraging a combination of electromechanical and hydraulic components. The design of the actuator is described herein, and results of an experimental characterization are provided that indicate that the actuator is capable of providing the functional capabilities required of an ankle prosthesis in a compact and lightweight package.
Electrical Properties and Power Considerations of a Piezoelectric Actuator

NASA Technical Reports Server (NTRS)

Jordan, T.; Ounaies, Z.; Tripp, J.; Tcheng, P.

1999-01-01

This paper assesses the electrical characteristics of piezoelectric wafers for use in aeronautical applications such as active noise control in aircraft. Determination of capacitive behavior and power consumption is necessary to optimize the system configuration and to design efficient driving electronics. Empirical relations are developed from experimental data to predict the capacitance and loss tangent of a PZT5A ceramic as nonlinear functions of both applied peak voltage and driving frequency. Power consumed by the PZT is the rate of energy required to excite the piezoelectric system along with power dissipated due to dielectric loss and mechanical and structural damping. Overall power consumption is thus quantified as a function of peak applied voltage and driving frequency. It was demonstrated that by incorporating the variation of capacitance and power loss with voltage and frequency, satisfactory estimates of power requirements can be obtained. These relations allow general guidelines in selection and application of piezoelectric actuators and driving electronics for active control applications.
Effects of elevated H+ and Pi on the contractile mechanics of skeletal muscle fibres from young and old men: implications for muscle fatigue in humans.

PubMed

Sundberg, Christopher W; Hunter, Sandra K; Trappe, Scott W; Smith, Carolyn S; Fitts, Robert H

2018-05-28

The mechanisms for the loss in muscle power and increased fatigability with ageing are unresolved. We show that the contractile mechanics of fibres from the vastus lateralis of old men were well-preserved compared to young men, but the selective loss of fast myosin heavy chain (MHC) II muscle was strongly associated with age-related decrements in whole-muscle strength and power. We reveal that the combination of acidosis (H + ) and inorganic phosphate (P i ) is an important mediator of muscle fatigue in humans by inhibiting the low- to high-force state of the cross-bridge cycle and peak power, but the depressive effects of these ions on cross-bridge function were similar in fibres from young and old men. These findings suggest the age-related loss in muscle power is due primarily to the atrophy of fast fibres, but the age-related increased fatigability cannot be explained by an increased sensitivity of the cross-bridge to H + and P i . The purpose of this study was to identify the mechanisms for the loss in muscle power and increased fatigability with ageing by integrating measures of whole-muscle function with single fibre contractile mechanics. After adjusting for the 22% smaller muscle mass in old (73-89 yrs, n = 6) compared with young men (20-29 yrs, n = 6), isometric torque and power output of the knee extensors were, respectively, 38% and 53% lower with age. Fatigability was ∼2.5-fold greater with age and strongly associated with the reductions in the electrically-evoked contractile properties. To test whether cross-bridge mechanisms could explain age-related decrements in knee extensor function, we exposed myofibres (n = 254) from the vastus lateralis to conditions mimicking quiescent muscle and fatiguing levels of H + (pH 6.2) and P i (30 mM). The fatigue-mimicking condition caused marked reductions in force, shortening velocity, and power and inhibited the low- to high-force state of the cross-bridge cycle, confirming non-human studies that these ions act synergistically to impair cross-bridge function. Other than severe age-related atrophy of fast fibres (-55%), contractile function and the depressive effects of the fatigue-mimicking condition did not differ in fibres from young and old men. The selective loss of fast MHC II muscle was strongly associated with the age-related decrease in isometric torque (r = 0.785) and power (r = 0.861). These data suggest that the age-related loss in muscle strength and power is due primarily to the atrophy of fast fibres, but that the age-related increased fatigability cannot be explained by an increased sensitivity of the cross-bridge to H + and P i . This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
The relation of turbulence to diffusion in open-channel flows

USGS Publications Warehouse

Keefer, Thomas N.

1971-01-01

The exponent in the power-law equation describing the decay of scalar quantities downstream of a jet is a linear function of the shear velocity of the channel. The length of the core region of a jet is a power-law function of the jet strength with the exponent depending on boundary roughness.

Anaerobic power and physical function in strength-trained and non-strength-trained older adults.

PubMed

Slade, Jill M; Miszko, Tanya A; Laity, Jennifer H; Agrawal, Subodoh K; Cress, M Elaine

2002-03-01

Challenging daily tasks, such as transferring heavy items or rising from the floor, may be dependent on the ability to generate short bursts of energy anaerobically. The purposes of this study were to determine if strength-trained (ST) older adults have higher anaerobic power output compared with non-strength-trained (NST) older adults and to determine the relationship between anaerobic power and performance-based physical function. Thirty-five men and women (age 71.5 +/- 6.4 years, mean +/- SD; NST: n = 18, ST: n = 17) were grouped by training status. Outcome variables included relative anaerobic power (Wingate test), physical function measured with the Continuous Scale Physical Functional Performance Test (CS-PFP, scaled 0 to 100), and anthropometric lean thigh volume (LTV). Analysis of covariance (with age and sex as covariates) was used to determine group differences in the dependent variables listed above. Pearson's r was used to determine the relationship between anaerobic power, CS-PFP total score (TOT), and CS-PFP lower body strength domain score (LBS). The ST group had significantly higher mean anaerobic power (NST 58.9 +/- 16 W/l, ST 96.3 +/- 23 W/l), CS-PFP total (NST 61.2 +/- 13, ST 73.7 +/- 8), and LBS (NST 54.1 +/- 17, ST 70.9 +/- 8) compared with the NST group (p <.05). However, LTV was similar for both groups (NST 3.323 +/- 0.75; ST 3.179 +/- 0.79), which suggests that the ST group had higher muscle quality compared with the NST group. Anaerobic power was significantly related to TOT (r =.611, p =.001) and LBS (r =.650, p =.001). High levels of physical function in ST older adults may in part be explained by higher levels of anaerobic power associated with strength training.
Oscillatory lower body negative pressure impairs working memory task-related functional hyperemia in healthy volunteers.

PubMed

Merchant, Sana; Medow, Marvin S; Visintainer, Paul; Terilli, Courtney; Stewart, Julian M

2017-04-01

Neurovascular coupling (NVC) describes the link between an increase in task-related neural activity and increased cerebral blood flow denoted "functional hyperemia." We previously showed induced cerebral blood flow oscillations suppressed functional hyperemia; conversely functional hyperemia also suppressed cerebral blood flow oscillations. We used lower body negative pressure (OLBNP) oscillations to force oscillations in middle cerebral artery cerebral blood flow velocity (CBFv). Here, we used N-back testing, an intellectual memory challenge as a neural activation task, to test the hypothesis that OLBNP-induced oscillatory cerebral blood flow can reduce functional hyperemia and NVC produced by a working memory task and can interfere with working memory. We used OLBNP (-30 mmHg) at 0.03, 0.05, and 0.10 Hz and measured spectral power of CBFv at all frequencies. Neither OLBNP nor N-back, alone or combined, affected hemodynamic parameters. 2-Back power and OLBNP individually were compared with 2-back power during OLBNP. 2-Back alone produced a narrow band increase in oscillatory arterial pressure (OAP) and oscillatory cerebral blood flow power centered at 0.0083 Hz. Functional hyperemia in response to 2-back was reduced to near baseline and 2-back memory performance was decreased by 0.03-, 0.05-, and 0.10-Hz OLBNP. OLBNP alone produced increased oscillatory power at frequencies of oscillation not suppressed by added 2-back. However, 2-back preceding OLBNP suppressed OLBNP power. OLBNP-driven oscillatory CBFv blunts NVC and memory performance, while memory task reciprocally interfered with forced CBFv oscillations. This shows that induced cerebral blood flow oscillations suppress functional hyperemia and functional hyperemia suppresses cerebral blood flow oscillations. NEW & NOTEWORTHY We show that induced cerebral blood flow oscillations suppress functional hyperemia produced by a working memory task as well as memory task performance. We conclude that oscillatory cerebral blood flow produces causal reductions of memory task neurovascular coupling and memory task performance. Reductions of functional hyperemia are constrained by autoregulation. Copyright © 2017 the American Physiological Society.
Literacy and Community Pariticpation. Prepublication Draft.

ERIC Educational Resources Information Center

Peschke, Edith

Literacy experts in composition have examined the exclusionary forces of academic discourse, and have identified various forms of classroom power that result from the system of academic literacy. Little is understood about the power relations that function to relate and regulate the classroom. Largely a humanistic notion, literacy has been defined…
Bacterial Fission, Powers of Two, Sociology, Environmental Science, Public Health, Biology, Mathematics: An Integration of Constructivism, Discovery, and Inquiry

ERIC Educational Resources Information Center

Schlenker, Richard; Tierney, Kathleen

2006-01-01

Students examine the bacterial expansion pattern and attempt to relate what they discover to expanding powers of two. They also relate what they see and discover to increasing living space requirements in a world of infinite space and finite space to discover that living space decreases as a function of one over expanding powers of two. The…
Repetitive transcranial magnetic stimulation improves consciousness disturbance in stroke patients: A quantitative electroencephalography spectral power analysis.

PubMed

Xie, Ying; Zhang, Tong

2012-11-05

Repetitive transcranial magnetic stimulation is a noninvasive treatment technique that can directly alter cortical excitability and improve cerebral functional activity in unconscious patients. To investigate the effects and the electrophysiological changes of repetitive transcranial magnetic stimulation cortical treatment, 10 stroke patients with non-severe brainstem lesions and with disturbance of consciousness were treated with repetitive transcranial magnetic stimulation. A quantitative electroencephalography spectral power analysis was also performed. The absolute power in the alpha band was increased immediately after the first repetitive transcranial magnetic stimulation treatment, and the energy was reduced in the delta band. The alpha band relative power values slightly decreased at 1 day post-treatment, then increased and reached a stable level at 2 weeks post-treatment. Glasgow Coma Score and JFK Coma Recovery Scale-Revised score were improved. Relative power value in the alpha band was positively related to Glasgow Coma Score and JFK Coma Recovery Scale-Revised score. These data suggest that repetitive transcranial magnetic stimulation is a noninvasive, safe, and effective treatment technology for improving brain functional activity and promoting awakening in unconscious stroke patients.
Are resting state spectral power measures related to executive functions in healthy young adults?

PubMed

Gordon, Shirley; Todder, Doron; Deutsch, Inbal; Garbi, Dror; Getter, Nir; Meiran, Nachshon

2018-01-08

Resting-state electroencephalogram (rsEEG) has been found to be associated with psychopathology, intelligence, problem solving, academic performance and is sometimes used as a supportive physiological indicator of enhancement in cognitive training interventions (e.g. neurofeedback, working memory training). In the current study, we measured rsEEG spectral power measures (relative power, between-band ratios and asymmetry) in one hundred sixty five young adults who were also tested on a battery of executive function (EF). We specifically focused on upper Alpha, Theta and Beta frequency bands given their putative role in EF. Our indices enabled finding correlations since they had decent-to-excellent internal and retest reliability and very little range restriction relative to a nation-wide representative large sample. Nonetheless, Bayesian statistical inference indicated support for the null hypothesis concerning lack of monotonic correlation between EF and rsEEG spectral power measures. Therefore, we conclude that, contrary to the quite common interpretation, these rsEEG spectral power measures do not indicate individual differences in the measured EF abilities. Copyright © 2017 Elsevier Ltd. All rights reserved.
Changes in power and force generation during coupled eccentric-concentric versus concentric muscle contraction with training and aging.

PubMed

Caserotti, Paolo; Aagaard, Per; Puggaard, Lis

2008-05-01

Age-related decline in maximal concentric muscle power is associated with frailty and functional impairments in the elderly. Compared to concentric contraction, mechanical muscle output is generally enhanced when muscles are rapidly pre-stretched (eccentric contraction), albeit less pronounced with increasing age. Exercise has been recommended to prevent loss of muscle power and function and recent guidelines indicate training program for increasing muscle power highly relevant for elderly subjects. This study examined the differences in muscle power, force and movement pattern during concentric-alone and coupled eccentric-concentric contraction and selected functional motor performances before and after 36-week multicomponent training including aerobic, strength, balance, flexibility and coordination components in elderly males. Vertical force, excursion, velocity, power and acceleration of the body center of mass were measured in two standardised vertical jumps (squatting jump, SQJ; countermovement jump, CMJ). Pre-stretch enhancement during CMJ did not improve performance [i.e., no enhanced maximal muscle power (Ppeak) and jump height (JH)] compared to concentric-alone muscle contraction (SQJ). Nevertheless, pre-stretch enhancement occurred as for similar SQJ and CMJ maximal performance, elderly people employed lower mechanical work, higher mean muscle power (Pmean), shorter concentric phase duration and shorter body center of mass displacement during CMJ. Post training, CMJ Ppeak, Pmean and JH increased in training group (P<0.05) while Ppeak and JH decreased in control group during the CMJ and SQJ (P<0.05). In conclusion, long-term training counteracted the age-related decline in muscle power and functional performance observed in the control subjects, while substantial gains in muscular performance were observed in the trained elderly.
Increased power spectral density in resting-state pain-related brain networks in fibromyalgia.

PubMed

Kim, Ji-Young; Kim, Seong-Ho; Seo, Jeehye; Kim, Sang-Hyon; Han, Seung Woo; Nam, Eon Jeong; Kim, Seong-Kyu; Lee, Hui Joong; Lee, Seung-Jae; Kim, Yang-Tae; Chang, Yongmin

2013-09-01

Fibromyalgia (FM), characterized by chronic widespread pain, is known to be associated with heightened responses to painful stimuli and atypical resting-state functional connectivity among pain-related regions of the brain. Previous studies of FM using resting-state functional magnetic resonance imaging (rs-fMRI) have focused on intrinsic functional connectivity, which maps the spatial distribution of temporal correlations among spontaneous low-frequency fluctuation in functional MRI (fMRI) resting-state data. In the current study, using rs-fMRI data in the frequency domain, we investigated the possible alteration of power spectral density (PSD) of low-frequency fluctuation in brain regions associated with central pain processing in patients with FM. rsfMRI data were obtained from 19 patients with FM and 20 age-matched healthy female control subjects. For each subject, the PSDs for each brain region identified from functional connectivity maps were computed for the frequency band of 0.01 to 0.25 Hz. For each group, the average PSD was determined for each brain region and a 2-sample t test was performed to determine the difference in power between the 2 groups. According to the results, patients with FM exhibited significantly increased frequency power in the primary somatosensory cortex (S1), supplementary motor area (SMA), dorsolateral prefrontal cortex, and amygdala. In patients with FM, the increase in PSD did not show an association with depression or anxiety. Therefore, our findings of atypical increased frequency power during the resting state in pain-related brain regions may implicate the enhanced resting-state baseline neural activity in several brain regions associated with pain processing in FM. Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
Intracranial mapping of auditory perception: event-related responses and electrocortical stimulation.

PubMed

Sinai, A; Crone, N E; Wied, H M; Franaszczuk, P J; Miglioretti, D; Boatman-Reich, D

2009-01-01

We compared intracranial recordings of auditory event-related responses with electrocortical stimulation mapping (ESM) to determine their functional relationship. Intracranial recordings and ESM were performed, using speech and tones, in adult epilepsy patients with subdural electrodes implanted over lateral left cortex. Evoked N1 responses and induced spectral power changes were obtained by trial averaging and time-frequency analysis. ESM impaired perception and comprehension of speech, not tones, at electrode sites in the posterior temporal lobe. There was high spatial concordance between ESM sites critical for speech perception and the largest spectral power (100% concordance) and N1 (83%) responses to speech. N1 responses showed good sensitivity (0.75) and specificity (0.82), but poor positive predictive value (0.32). Conversely, increased high-frequency power (>60Hz) showed high specificity (0.98), but poorer sensitivity (0.67) and positive predictive value (0.67). Stimulus-related differences were observed in the spatial-temporal patterns of event-related responses. Intracranial auditory event-related responses to speech were associated with cortical sites critical for auditory perception and comprehension of speech. These results suggest that the distribution and magnitude of intracranial auditory event-related responses to speech reflect the functional significance of the underlying cortical regions and may be useful for pre-surgical functional mapping.
Intracranial mapping of auditory perception: Event-related responses and electrocortical stimulation

PubMed Central

Sinai, A.; Crone, N.E.; Wied, H.M.; Franaszczuk, P.J.; Miglioretti, D.; Boatman-Reich, D.

2010-01-01

Objective We compared intracranial recordings of auditory event-related responses with electrocortical stimulation mapping (ESM) to determine their functional relationship. Methods Intracranial recordings and ESM were performed, using speech and tones, in adult epilepsy patients with subdural electrodes implanted over lateral left cortex. Evoked N1 responses and induced spectral power changes were obtained by trial averaging and time-frequency analysis. Results ESM impaired perception and comprehension of speech, not tones, at electrode sites in the posterior temporal lobe. There was high spatial concordance between ESM sites critical for speech perception and the largest spectral power (100% concordance) and N1 (83%) responses to speech. N1 responses showed good sensitivity (0.75) and specificity (0.82), but poor positive predictive value (0.32). Conversely, increased high-frequency power (>60 Hz) showed high specificity (0.98), but poorer sensitivity (0.67) and positive predictive value (0.67). Stimulus-related differences were observed in the spatial-temporal patterns of event-related responses. Conclusions Intracranial auditory event-related responses to speech were associated with cortical sites critical for auditory perception and comprehension of speech. Significance These results suggest that the distribution and magnitude of intracranial auditory event-related responses to speech reflect the functional significance of the underlying cortical regions and may be useful for pre-surgical functional mapping. PMID:19070540
Solar radiation - to - power generation models for one-axis tracking PV system with on-site measurements from Eskisehir, Turkey

NASA Astrophysics Data System (ADS)

Filik, Tansu; Başaran Filik, Ümmühan; Nezih Gerek, Ömer

2017-11-01

In this study, new analytic models are proposed for mapping on-site global solar radiation values to electrical power output values in solar photovoltaic (PV) panels. The model extraction is achieved by simultaneously recording solar radiation and generated power from fixed and tracking panels, each with capacity of 3 kW, in Eskisehir (Turkey) region. It is shown that the relation between the solar radiation and the corresponding electric power is not only nonlinear, but it also exhibits an interesting time-varying characteristic in the form of a hysteresis function. This observed radiation-to-power relation is, then, analytically modelled with three piece-wise function parts (corresponding to morning, noon and evening times), which is another novel contribution of this work. The model is determined for both fixed panels and panels with a tracking system. Especially the panel system with a dynamic tracker produces a harmonically richer (with higher values in general) characteristic, so higher order polynomial models are necessary for the construction of analytical solar radiation models. The presented models, characteristics of the hysteresis functions, and differences in the fixed versus solar-tracking panels are expected to provide valuable insight for further model based researches.
Motivation, affect, and hemispheric asymmetry: power versus affiliation.

PubMed

Kuhl, Julius; Kazén, Miguel

2008-08-01

In 4 experiments, the authors examined to what extent information related to different social needs (i.e., power vs. affiliation) is associated with hemispheric laterality. Response latencies to a lateralized dot-probe task following lateralized pictures or verbal labels that were associated with positive or negative episodes related to power, affiliation, or achievement revealed clear-cut laterality effects. These effects were a function of need content rather than of valence: Power-related stimuli were associated with right visual field (left hemisphere) superiority, whereas affiliation-related stimuli were associated with left visual field (right hemisphere) superiority. Additional results demonstrated that in contrast to power, affiliation primes were associated with better discrimination between coherent word triads (e.g., goat, pass, and green, all related to mountain) and noncoherent triads, a remote associate task known to activate areas of the right hemisphere. (c) 2008 APA, all rights reserved
Evaluation of high-voltage, high-power, solid-state remote power controllers for amps

NASA Technical Reports Server (NTRS)

Callis, Charles P.

1987-01-01

The Electrical Power Branch at Marshall Space Flight Center has a Power System Development Facility where various power circuit breadboards are tested and evaluated. This project relates to the evaluation of a particular remote power controller (RPC) energizing high power loads. The Facility equipment permits the thorough testing and evaluation of high-voltage, high-power solid-state remote power controllers. The purpose is to evaluate a Type E, 30 Ampere, 200 V dc remote power controller. Three phases of the RPC evaluation are presented. The RPC is evaluated within a low-voltage, low-power circuit to check its operational capability. The RPC is then evaluated while performing switch/circuit breaker functions within a 200 V dc, 30 Ampere power circuit. The final effort of the project relates to the recommended procedures for installing these RPC's into the existing Autonomously Managed Power System (AMPS) breadboard/test facility at MSFC.
Factors affecting sexual function: A comparison between women with gynecological or rectal cancer and healthy controls.

PubMed

Li, Chia-Chun; Rew, Lynn; Chen, Lynn

2015-03-01

This study had two purposes: (i) to explore differences in sexual function between women with gynecological or rectal cancer after related pelvic-area treatments and women without cancer; and (ii) to investigate the relationships among body image, anxiety and depression, sexual relationship power, sexual self-schema, and female sexual function. The participants (n = 139) were recruited through Internet cancer support groups and women's health organizations in the USA. Six structured questionnaires were mailed, and the data were analyzed using descriptive and inferential statistics. The results showed that women with gynecological or rectal cancer had significantly worse sexual function than women without cancer. Having gynecological/rectal cancer and a negative sexual self-schema were significantly related to poor sexual function. Furthermore, sexual self-schema moderated the relationship between sexual relationship power and female sexual function. Healthcare providers could give more attention to sexual issues in women who have undergone treatment for gynecological or rectal cancer, especially for those with a negative sexual self-schema and high sexual relationship power, which might improve these women's quality of life. © 2014 Wiley Publishing Asia Pty Ltd.
Distinct slow and fast cortical theta dynamics in episodic memory retrieval.

PubMed

Pastötter, Bernhard; Bäuml, Karl-Heinz T

2014-07-01

Brain oscillations in the theta frequency band (3-8 Hz) have been shown to be critically involved in human episodic memory retrieval. In prior work, both positive and negative relationships between cortical theta power and retrieval success have been reported. This study examined the hypothesis that slow and fast cortical theta oscillations at the edges of the traditional theta frequency band are differentially related to retrieval success. Scalp EEG was recorded in healthy human participants as they performed a cued-recall episodic memory task. Slow (~3 Hz) and fast (~7 Hz) theta oscillations at retrieval were examined as a function of whether an item was recalled or not and as a function of the items' output position at test. Recall success typically declines with output position, due to increases in interference level. The results showed that slow theta power was positively related but fast theta power was negatively related to retrieval success. Concurrent positive and negative episodic memory effects for slow and fast theta oscillations were dissociable in time and space, showing different time courses and different spatial locations on the scalp. Moreover, fast theta power increased from early to late output positions, whereas slow theta power was unaffected by items' output position. Together with prior work, the results suggest that slow and fast theta oscillations have distinct functional roles in episodic memory retrieval, with slow theta oscillations being related to processes of recollection and conscious awareness, and fast theta oscillations being linked to processes of interference and interference resolution. Copyright © 2014 Elsevier Inc. All rights reserved.
47 CFR 27.4 - Terms and definitions.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Radiated Power (ERP) (in a given direction). The product of the power supplied to the antenna and its gain... product of the power supplied to the antenna and the antenna gain in a given direction relative to an... performance of the essential functions that could be performed at the transmitter. Satellite Digital Audio...
How animals move: comparative lessons on animal locomotion.

PubMed

Schaeffer, Paul J; Lindstedt, Stan L

2013-01-01

Comparative physiology often provides unique insights in animal structure and function. It is specifically through this lens that we discuss the fundamental properties of skeletal muscle and animal locomotion, incorporating variation in body size and evolved difference among species. For example, muscle frequencies in vivo are highly constrained by body size, which apparently tunes muscle use to maximize recovery of elastic recoil potential energy. Secondary to this constraint, there is an expected linking of skeletal muscle structural and functional properties. Muscle is relatively simple structurally, but by changing proportions of the few muscle components, a diverse range of functional outputs is possible. Thus, there is a consistent and predictable relation between muscle function and myocyte composition that illuminates animal locomotion. When animals move, the mechanical properties of muscle diverge from the static textbook force-velocity relations described by A. V. Hill, as recovery of elastic potential energy together with force and power enhancement with activation during stretch combine to modulate performance. These relations are best understood through the tool of work loops. Also, when animals move, locomotion is often conveniently categorized energetically. Burst locomotion is typified by high-power outputs and short durations while sustained, cyclic, locomotion engages a smaller fraction of the muscle tissue, yielding lower force and power. However, closer examination reveals that rather than a dichotomy, energetics of locomotion is a continuum. There is a remarkably predictable relationship between duration of activity and peak sustainable performance.
Public speaking in front of an unreceptive audience increases implicit power motivation and its endocrine arousal signature.

PubMed

Wiemers, Uta S; Schultheiss, Oliver C; Wolf, Oliver T

2015-05-01

The present study explored the motivational characteristics of the Trier Social Stress Test (TSST; Kirschbaum, Pirke, & Hellhammer, 1993). Seventy-two participants either completed the public-speaking component of the TSST or, as a control condition, the friendly TSST (Wiemers, Schoofs, & Wolf, 2013) and wrote picture stories both before and after treatment. Stories were coded for motivational imagery related to power, achievement, and affiliation as well as for activity inhibition, a marker of functional brain lateralization during stress. The TSST had a specific arousing effect on power motivation, but not on other motivational needs, on activity inhibition, or on story length. TSST-elicited increases in power imagery, but not in achievement or affiliation imagery, were associated with a relatively greater salivary alpha-amylase response and with a relatively lesser salivary cortisol response. These findings suggest that the TSST specifically induces power-related stress. Copyright © 2015 Elsevier Inc. All rights reserved.
Sound radiation quantities arising from a resilient circular radiator.

PubMed

Aarts, Ronald M; Janssen, Augustus J E M

2009-10-01

Power series expansions in ka are derived for the pressure at the edge of a radiator, the reaction force on the radiator, and the total radiated power arising from a harmonically excited, resilient, flat, circular radiator of radius a in an infinite baffle. The velocity profiles on the radiator are either Stenzel functions (1-(sigma/a)2)n, with sigma the radial coordinate on the radiator, or linear combinations of Zernike functions Pn(2(sigma/a)2-1), with Pn the Legendre polynomial of degree n. Both sets of functions give rise, via King's integral for the pressure, to integrals for the quantities of interest involving the product of two Bessel functions. These integrals have a power series expansion and allow an expression in terms of Bessel functions of the first kind and Struve functions. Consequently, many of the results in [M. Greenspan, J. Acoust. Soc. Am. 65, 608-621 (1979)] are generalized and treated in a unified manner. A foreseen application is for loudspeakers. The relation between the radiated power in the near-field on one hand and in the far field on the other is highlighted.
The effect of a hot, spherical scattering cloud on quasi-periodic oscillation behavior

NASA Astrophysics Data System (ADS)

Bussard, R. W.; Weisskopf, M. C.; Elsner, R. F.; Shibazaki, N.

1988-04-01

A Monte Carlo technique is used to investigate the effects of a hot electron scattering cloud surrounding a time-dependent X-ray source. Results are presented for the time-averaged emergent energy spectra and the mean residence time in the cloud as a function of energy. Moreover, after Fourier transforming the scattering Green's function, it is shown how the cloud affects both the observed power spectrum of a time-dependent source and the cross spectrum (Fourier transform of a cross correlation between energy bands). It is found that the power spectra intrinsic to the source are related to those observed by a relatively simple frequency-dependent multiplicative factor (a transmission function). The cloud can severely attenuate high frequencies in the power spectra, depending on optical depth, and, at lower frequencies, the transmission function has roughly a Lorentzian shape. It is also found that if the intrinsic energy spectrum is constant in time, the phase of the cross spectrum is determined entirely by scattering. Finally, the implications of the results for studies of the X-ray quasi-periodic oscillators are discussed.

12 CFR 150.150 - Who is responsible for the exercise of fiduciary powers?

Code of Federal Regulations, 2014 CFR

2014-01-01

... 12 Banks and Banking 1 2014-01-01 2014-01-01 false Who is responsible for the exercise of... and Facilities § 150.150 Who is responsible for the exercise of fiduciary powers? The exercise of your... responsibilities, the board may assign any function related to the exercise of fiduciary powers to any director...
12 CFR 150.150 - Who is responsible for the exercise of fiduciary powers?

Code of Federal Regulations, 2012 CFR

2012-01-01

... 12 Banks and Banking 1 2012-01-01 2012-01-01 false Who is responsible for the exercise of... and Facilities § 150.150 Who is responsible for the exercise of fiduciary powers? The exercise of your... responsibilities, the board may assign any function related to the exercise of fiduciary powers to any director...
12 CFR 550.150 - Who is responsible for the exercise of fiduciary powers?

Code of Federal Regulations, 2011 CFR

2011-01-01

... 12 Banks and Banking 5 2011-01-01 2011-01-01 false Who is responsible for the exercise of... Facilities § 550.150 Who is responsible for the exercise of fiduciary powers? The exercise of your fiduciary... responsibilities, the board may assign any function related to the exercise of fiduciary powers to any director...
12 CFR 550.150 - Who is responsible for the exercise of fiduciary powers?

Code of Federal Regulations, 2012 CFR

2012-01-01

... 12 Banks and Banking 6 2012-01-01 2012-01-01 false Who is responsible for the exercise of... Facilities § 550.150 Who is responsible for the exercise of fiduciary powers? The exercise of your fiduciary... responsibilities, the board may assign any function related to the exercise of fiduciary powers to any director...
12 CFR 150.150 - Who is responsible for the exercise of fiduciary powers?

Code of Federal Regulations, 2013 CFR

2013-01-01

... 12 Banks and Banking 1 2013-01-01 2013-01-01 false Who is responsible for the exercise of... and Facilities § 150.150 Who is responsible for the exercise of fiduciary powers? The exercise of your... responsibilities, the board may assign any function related to the exercise of fiduciary powers to any director...
ACE I/D and ACTN3 R/X polymorphisms as potential factors in modulating exercise-related phenotypes in older women in response to a muscle power training stimuli.

PubMed

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.
Electrical power generating system

NASA Technical Reports Server (NTRS)

Nola, F. J. (Inventor)

1983-01-01

A power generating system for adjusting coupling an induction motor, as a generator, to an A.C. power line wherein the motor and power line are connected through a triac is described. The triac is regulated to normally turn on at a relatively late point in each half cycle of its operation, whereby at less than operating speed, and thus when the induction motor functions as a motor rather than as a generator, power consumption from the line is substantially reduced.
Drawing ellipses in water: evidence for dynamic constraints in the relation between velocity and path curvature.

PubMed

Catavitello, Giovanna; Ivanenko, Yuri P; Lacquaniti, Francesco; Viviani, Paolo

2016-06-01

Several types of continuous human movements comply with the so-called Two-Thirds Power Law (2/3-PL) stating that velocity (V) is a power function of the radius of curvature (R) of the endpoint trajectory. The origin of the 2/3-PL has been the object of much debate. An experiment investigated further this issue by comparing two-dimensional drawing movements performed in air and water. In both conditions, participants traced continuously quasi-elliptic trajectories (period T = 1.5 s). Other experimental factors were the movement plane (horizontal/vertical), and whether the movement was performed free-hand, or by following the edge of a template. In all cases a power function provided a good approximation to the V-R relation. The main result was that the exponent of the power function in water was significantly smaller than in air. This appears incompatible with the idea that the power relationship depends only on kinematic constraints and suggests a significant contribution of dynamic factors. We argue that a satisfactory explanation of the observed behavior must take into account the interplay between the properties of the central motor commands and the visco-elastic nature of the mechanical plant that implements the commands.
Differences in myoelectric and body-powered upper-limb prostheses: Systematic literature review.

PubMed

Carey, Stephanie L; Lura, Derek J; Highsmith, M Jason

2015-01-01

The choice of a myoelectric or body-powered upper-limb prosthesis can be determined using factors including control, function, feedback, cosmesis, and rejection. Although body-powered and myoelectric control strategies offer unique functions, many prosthesis users must choose one. A systematic review was conducted to determine differences between myoelectric and body-powered prostheses to inform evidence-based clinical practice regarding prescription of these devices and training of users. A search of 9 databases identified 462 unique publications. Ultimately, 31 of them were included and 11 empirical evidence statements were developed. Conflicting evidence has been found in terms of the relative functional performance of body-powered and myoelectric prostheses. Body-powered prostheses have been shown to have advantages in durability, training time, frequency of adjustment, maintenance, and feedback; however, they could still benefit from improvements of control. Myoelectric prostheses have been shown to improve cosmesis and phantom-limb pain and are more accepted for light=intensity work. Currently, evidence is insufficient to conclude that either system provides a significant general advantage. Prosthetic selection should be based on a patient's individual needs and include personal preferences, prosthetic experience, and functional needs. This work demonstrates that there is a lack of empirical evidence regarding functional differences in upper-limb prostheses.
Concentrated solar power generation using solar receivers

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

Anderson, Bruce N.; Treece, William Dean; Brown, Dan

Inventive concentrated solar power systems using solar receivers, and related devices and methods, are generally described. Low pressure solar receivers are provided that function to convert solar radiation energy to thermal energy of a working fluid, e.g., a working fluid of a power generation or thermal storage system. In some embodiments, low pressure solar receivers are provided herein that are useful in conjunction with gas turbine based power generation systems.
Time-domain comparisons of power law attenuation in causal and noncausal time-fractional wave equations

PubMed Central

Zhao, Xiaofeng; McGough, Robert J.

2016-01-01

The attenuation of ultrasound propagating in human tissue follows a power law with respect to frequency that is modeled by several different causal and noncausal fractional partial differential equations. To demonstrate some of the similarities and differences that are observed in three related time-fractional partial differential equations, time-domain Green's functions are calculated numerically for the power law wave equation, the Szabo wave equation, and for the Caputo wave equation. These Green's functions are evaluated for water with a power law exponent of y = 2, breast with a power law exponent of y = 1.5, and liver with a power law exponent of y = 1.139. Simulation results show that the noncausal features of the numerically calculated time-domain response are only evident very close to the source and that these causal and noncausal time-domain Green's functions converge to the same result away from the source. When noncausal time-domain Green's functions are convolved with a short pulse, no evidence of noncausal behavior remains in the time-domain, which suggests that these causal and noncausal time-fractional models are equally effective for these numerical calculations. PMID:27250193
Photo-detachment of negative ions in Ar-CO2 dc discharge employing Langmuir probe

NASA Astrophysics Data System (ADS)

Rodríguez, Jannet; Yousif, Farook Bashir; Fuentes, Beatriz E.; Vázquez, Federico; Rivera, Marco; López-Patiño, J.; Figueroa, Aldo; Martínez, Horacio

2018-05-01

The electronegativity of the A r - C O 2 gas mixture was investigated, and the total relative negative oxygen ion density O2- + O- in the bulk of a dc discharge has been determined employing Langmuir probe assisted laser photo-detachment. The relative electron density and absolute temperature were obtained for the mixture at discharge powers between 200 and 3000 mW and pressures between 0.2 and 0.6 mbar, employing the collisional radiative model for several Ar gas mixtures. The absolute metastable number density for 1s3 and 1s5 levels was measured, and both showed an increasing trend as a function of pressure and power. The absolute number density of the 1s5 level was found to be higher than that of the 1s3 level. Electronegativity was found to decrease as a function of power and as a function of the increasing Ar percentage in the gas mixture.
Periodicities in solar wind-magnetosphere coupling functions and geomagnetic activity during the past solar cycles

NASA Astrophysics Data System (ADS)

Andriyas, T.; Andriyas, S.

2017-09-01

In this paper, we study the solar-terrestrial relation through the wavelet analysis. We report periodicities common between multiple solar wind coupling functions and geomagnetic indices during five solar cycles and also and the strength of this correspondence. The Dst (found to be most predictable in Newell et al., J. Geophys. Res. Space Phys. 112(A1):A01206, 2007) and AL (least predictable in Newell et al., J. Geophys. Res. Space Phys. 112(A1):A01206, 2007) indices are used for this purpose. During the years 1966-2016 (which includes five solar cycles 20, 21, 22, 23, and 24), prominent periodicities ≤720 days with power above 95% confidence level were found to occur around 27, 182, 385, and 648 days in the Dst index while those in the AL index were found in bands around 27, 187, and 472 days. Ten solar wind coupling functions were then used to find periodicities common with the indices. All the coupling functions had significant power in bands centered around 27, 280, and 648 days while powers in fluctuations around 182, 385, and 472 days were only found in some coupling functions. All the drivers and their variants had power above the significant level in the 280-288 days band, which was absent in the Dst and AL indices. The normalized scale averaged spectral power around the common periods in the coupling functions and the indices indicated that the coupling functions most correlated with the Dst index were the Newell (27 and 385 days), Wygant (182 days), and Scurry-Russell and Boynton (648 days) functions. An absence of common power between the coupling functions and the Dst index around the annual periodicity was noted during the even solar cycles. A similar analysis for the AL index indicated that Newell (27 days), Rectified (187 days), and Boynton (472 days) were the most correlated functions. It was also found that the correlation numbers were relatively weaker for the AL index, specially for the 187 day periodicity. It is concluded that as the two indices respond to solar wind forcing with varying levels of strength at various prominent scales and the coupling function used, the response might be dependent on the scale (days or months or years) of interest at which the solar wind driving is to be predicted.
Impaired voluntary neuromuscular activation limits muscle power in mobility-limited older adults

USDA-ARS?s Scientific Manuscript database

Background. Age-related alterations of neuromuscular activation may contribute to deficits in muscle power and mobility function. This study assesses whether impaired activation of the agonist quadriceps and antagonist hamstrings, including amplitude- and velocity-dependent characteristics of activa...
An Evaluation of Functional Sit-to-Stand Power in Cohorts of Healthy Adults Aged 18-97 Years.

PubMed

Glenn, Jordan M; Gray, Michelle; Vincenzo, Jennifer; Paulson, Sally; Powers, Melissa

2017-04-01

This investigation examined differences in functional sit-to-stand power/velocity between cohorts of adults aged 18-97 years. This study included 264 healthy adults classified into four cohorts (18-40, C1; 60-69, C2; 70-79, C2; ≥ 80, C4). Participants completed the sit-to-stand task five times. Power and velocity were measured via the TENDO power analyzer. Absolute average power was maintained from C1-C3, but decreased (p < .01) in C4. Absolute peak power decreased between C1-C2 (p < .01), was similar between C2-C3, and decreased in C4 (p < .01). Relative (to body weight) average and peak power decreased between C1-C2 (p < .01), was similar between C2-C3, and decreased in C4 (p < .01). Average velocity was similar between C1 and C2, but decreased in C3 (p < .01) and C4 (p < .01), respectively. Peak velocity was significantly different between all cohorts (p < .01). Declines in functional power may plateau during the seventh and eighth decades, accelerating after 80 years.
Performance and Scalability of Discriminative Metrics for Comparative Gene Identification in 12 Drosophila Genomes

PubMed Central

Lin, Michael F.; Deoras, Ameya N.; Rasmussen, Matthew D.; Kellis, Manolis

2008-01-01

Comparative genomics of multiple related species is a powerful methodology for the discovery of functional genomic elements, and its power should increase with the number of species compared. Here, we use 12 Drosophila genomes to study the power of comparative genomics metrics to distinguish between protein-coding and non-coding regions. First, we study the relative power of different comparative metrics and their relationship to single-species metrics. We find that even relatively simple multi-species metrics robustly outperform advanced single-species metrics, especially for shorter exons (≤240 nt), which are common in animal genomes. Moreover, the two capture largely independent features of protein-coding genes, with different sensitivity/specificity trade-offs, such that their combinations lead to even greater discriminatory power. In addition, we study how discovery power scales with the number and phylogenetic distance of the genomes compared. We find that species at a broad range of distances are comparably effective informants for pairwise comparative gene identification, but that these are surpassed by multi-species comparisons at similar evolutionary divergence. In particular, while pairwise discovery power plateaued at larger distances and never outperformed the most advanced single-species metrics, multi-species comparisons continued to benefit even from the most distant species with no apparent saturation. Last, we find that genes in functional categories typically considered fast-evolving can nonetheless be recovered at very high rates using comparative methods. Our results have implications for comparative genomics analyses in any species, including the human. PMID:18421375
Relationship Power, Sociodemographics, and Their Relative Influence on Sexual Agreements Among Gay Male Couples.

PubMed

Perry, Nicholas S; Huebner, David M; Baucom, Brian R; Hoff, Colleen C

2016-06-01

Men who have sex with men (MSM) in primary relationships engage in condomless sex both within and outside their relationships and a majority of HIV transmission risk may actually occur within primary relationships. Sexual agreements regarding non-monogamy are a critical component to understanding HIV prevention in male couples. Relationship factors have been associated with how sexual agreements function and power is one dyadic construct likely to affect couple's maintenance of non-monogamy agreements. Multilevel modeling was used in a cross-sectional study of gay male couples (N = 566 couples) to examine associations between partners' demographic characteristics traditionally used to define relationship power, a scale of decision-making power, and outcomes related to sexual agreements, including investment, agreement breaks, and break disclosure. Results indicated that decision-making power relative to one's partner was not associated with any agreement outcome, contrary to hypotheses. However, controlling for decision-making power, demographic bases of power were variably associated with sexual agreements' functioning. Younger partners were less invested in and more frequently broke their agreements. Lower-earning partners broke their agreements more frequently, but also disclosed breaks more often. White men in white-minority relationships broke their agreement more often than their partners. Concordant HIV-positive couples were less invested in their agreements and HIV-positive men disclosed breaks more frequently. HIV prevention efforts for same-sex couples must attend to the social, developmental, and cultural influences that affect their agreements around non-monogamy.
Muscle power failure in mobility-limited adults: preserved single muscle fibre function despite reduced whole muscle size, quality and neuromuscular activiation

USDA-ARS?s Scientific Manuscript database

This study investigated the physiological and gender determinants of the age-related loss of muscle power in 31 healthy middle-aged adults (aged 40-55 years), 28 healthy older adults (70-85 years) and 34 mobility-limited older adults (70-85 years). We hypothesized that leg extensor muscle power woul...
12 CFR 550.150 - Who is responsible for the exercise of fiduciary powers?

Code of Federal Regulations, 2014 CFR

2014-01-01

... 12 Banks and Banking 6 2014-01-01 2012-01-01 true Who is responsible for the exercise of fiduciary... Facilities § 550.150 Who is responsible for the exercise of fiduciary powers? The exercise of your fiduciary... responsibilities, the board may assign any function related to the exercise of fiduciary powers to any director...
12 CFR 550.150 - Who is responsible for the exercise of fiduciary powers?

Code of Federal Regulations, 2013 CFR

2013-01-01

... 12 Banks and Banking 6 2013-01-01 2012-01-01 true Who is responsible for the exercise of fiduciary... Facilities § 550.150 Who is responsible for the exercise of fiduciary powers? The exercise of your fiduciary... responsibilities, the board may assign any function related to the exercise of fiduciary powers to any director...

Surgery-Induced Changes and Early Recovery of Hip-Muscle Strength, Leg-Press Power, and Functional Performance after Fast-Track Total Hip Arthroplasty: A Prospective Cohort Study

PubMed Central

Holm, Bente; Thorborg, Kristian; Husted, Henrik; Kehlet, Henrik; Bandholm, Thomas

2013-01-01

Background By measuring very early changes in muscle strength and functional performance after fast-track total hip arthroplasty (THA), post-operative rehabilitation, introduced soon after surgery, can be designed to specifically target identified deficits. Objective(s) Firstly, to quantify changes (compared to pre-operative values) in hip muscle strength, leg-press power, and functional performance in the first week after THA, and secondly, to explore relationships between the muscle strength changes, and changes in hip pain, systemic inflammation, and thigh swelling. Design Prospective, cohort study. Setting Convenience sample of patients receiving a THA at Copenhagen University Hospital, Hvidovre, Denmark, between March and December 2011. Participants Thirty-five patients (65.9±7.2 years) undergoing THA. Main outcome measures Hip muscle strength, leg-press power, performance-based function, and self-reported disability were determined prior to, and 2 and 8 days after, THA (Day 2 and 8, respectively). Hip pain, thigh swelling, and C-Reactive Protein were also determined. Results Five patients were lost to follow-up. Hip muscle strength and leg press power were substantially reduced at Day 2 (range of reductions: 41–58%, P<0.001), but less pronounced at Day 8 (range of reductions: 23–31%, P<0.017). Self-reported symptoms and function (HOOS: Pain, Symptoms, and ADL) improved at Day 8 (P<0.014). Changes in hip pain, C-Reactive Protein, and thigh swelling were not related to the muscle strength and power losses. Conclusion(s) Hip muscle strength and leg-press power decreased substantially in the first week after THA – especially at Day 2 – with some recovery at Day 8. The muscle strength loss and power loss were not related to changes in hip pain, systemic inflammation, or thigh swelling. In contrast, self-reported symptoms and function improved. These data on surgery-induced changes in muscle strength may help design impairment-directed, post-operative rehabilitation to be introduced soon after surgery. Trial Registration ClinicalTrials.gov NCT01246674. PMID:23614020
Dynamic equations for an isotropic spherical shell using the power series method and surface differential operators

NASA Astrophysics Data System (ADS)

Okhovat, Reza; Boström, Anders

2017-04-01

Dynamic equations for an isotropic spherical shell are derived by using a series expansion technique. The displacement field is split into a scalar (radial) part and a vector (tangential) part. Surface differential operators are introduced to decrease the length of all equations. The starting point is a power series expansion of the displacement components in the thickness coordinate relative to the mid-surface of the shell. By using the expansions of the displacement components, the three-dimensional elastodynamic equations yield a set of recursion relations among the expansion functions that can be used to eliminate all but the four of lowest order and to express higher order expansion functions in terms of those of lowest orders. Applying the boundary conditions on the surfaces of the spherical shell and eliminating all but the four lowest order expansion functions give the shell equations as a power series in the shell thickness. After lengthy manipulations, the final four shell equations are obtained in a relatively compact form which are given to second order in shell thickness explicitly. The eigenfrequencies are compared to exact three-dimensional theory with excellent agreement and to membrane theory.
Redshift space clustering of galaxies and cold dark matter model

NASA Technical Reports Server (NTRS)

Bahcall, Neta A.; Cen, Renyue; Gramann, Mirt

1993-01-01

The distorting effect of peculiar velocities on the power speturm and correlation function of IRAS and optical galaxies is studied. The observed redshift space power spectra and correlation functions of IRAS and optical the galaxies over the entire range of scales are directly compared with the corresponding redshift space distributions using large-scale computer simulations of cold dark matter (CDM) models in order to study the distortion effect of peculiar velocities on the power spectrum and correlation function of the galaxies. It is found that the observed power spectrum of IRAS and optical galaxies is consistent with the spectrum of an Omega = 1 CDM model. The problems that such a model currently faces may be related more to the high value of Omega in the model than to the shape of the spectrum. A low-density CDM model is also investigated and found to be consistent with the data.
Improved parent-reported mobility and achievement of individual goals on activity and participation level after functional power-training in young children with cerebral palsy: a double-baseline controlled trial.

PubMed

van Vulpen, Liesbeth F; de Groot, Sonja; Rameckers, Eugene A; Becher, Jules G; Dallmeijer, Annet J

2018-03-07

In children with cerebral palsy (CP), strength training programs to improve walking capacity and participation in activities of daily living are commonly used in clinical practice, despite lacking evidence of its effectiveness. It has been suggested that strength training with high movement velocity could be more effective than traditional resistance training to improve functional abilities such as walking. In a recently published study, we have demonstrated the positive effects of functional high-velocity resistance (power) training on muscle strength and walking capacity in young children with CP. Whether this type of training is also effective in achieving individual predefined goals in daily activities and self-reported mobility limitations, has not yet been described however. To evaluate the effect of functional power-training on parent-reported mobility and achievement of individual goals on activity and participation level in young children with CP. A double-baseline design was used to compare a 14-week period usual care with a 14-week period of functional power-training (3 times a week) and a follow-up period of 14-weeks. Twenty-two children with spastic CP (13 bilateral, GMFCS level I (N=10) and level II (N=12), mean age 7.5 years (SD 1.8, range 4-10 y)) and their parents participated. Outcome measures were goal attainment scaling (GAS) of individual daily activity related treatment goals, mobility performance as measured using the Functional Mobility Scale (FMS-5m, 50m and 500m), and the parent-reported Mobility Questionnaire (MobQues). After power-training, 86% of children achieved or exceeded their goal, compared with 14% in the usual care period (p<.001). The probability of improvement by one point or more on the FMS- 500 meter after functional power-training was 10 times higher, compared with the usual care period (Relative Risk=10.0 with 95%CI 1.4 - 71.3). No changes were found in the FMS-5m and FMS-50m categories. Improvement on the MobQues was significantly greater after power-training compared with usual care (7.9% (95% CI 2.7 - 13.0, p=.005)). The improvement in performance in the activities defined in the treatment goals continued during the follow-up period. The results indicated that functional power- training is an effective training to achieve personalized treatment goals for activities in daily life and parent-reported mobility performance in young children with cerebral palsy.
[Electroencephalogram power development of cognitive function at age 7 to 12 years: a comparative study between attention deficit hyperactivity disorder and healthy children].

PubMed

Cheng, Q R; Shen, H J; Tu, W J; Zhang, Q F; Dong, X

2016-12-02

Objective: To compare brain electrical cognitive tasks and brain development between study about 7 to 12 years old attention deficit hyperactivity disorder (ADHD) and normal children. Method: Prospectic case-control study was used. A total of 110 children with ADHD (63 boys and 47 girls) and 116 normal children (66 boys and 50 girls), were enrolled in this study. The electroencephalogram (EEG) was recorded when attention tasks were conducted, the EEG power was extracted from the original data and comparatively analyzed the absolute power (θ, α, β spectrum) and relative power (θ/total, α/total, θ/α, θ/β). Result: (1) Absolute power: ADHD children θ absolute power was higher than that of normal children in Pz lead ((52±28) vs . (40±30)μV 2 , t =3.906, P <0.05), with statistical significance. (2) Relative power: θ/total, θ/α, θ/β in ADHD are higher than normal children(0.23±0.07 vs . 0.20±0.05, 1.35±0.76 vs . 1.00±0.56, 4.75±2.49 vs . 3.56±2.08, t =2.900 and 3.954 and 3.901, P =0.004 and 0.000 and 0.000), α/total in ADHD is lower (0.21±0.09 vs. 0.24±0.10, t =-2.517, P =0.013). (3) The comparative study of the development of EEG power θ/β between ADHD and normal children showed age-related correlation in both groups ( r =-0.378 and -0.398, P =0.000 for both). Conclusion: ADHD children's EEG power on slow spectrum was higher than that of the normal children, it was more significant in the parietal region than in frontal region. With the increase of age, the θ relative power in ADHD and normal children gradually declined, in the normal children it linearly related, but in ADHD there was no significant regularity. θ/β can be used as a sensitive index to assess ADHD children's cognitive function.
Suppression of no-longer relevant information in Working Memory: An alpha-power related mechanism?

PubMed

Poch, Claudia; Valdivia, María; Capilla, Almudena; Hinojosa, José Antonio; Campo, Pablo

2018-03-27

Selective attention can enhance Working Memory (WM) performance by selecting relevant information, while preventing distracting items from encoding or from further maintenance. Alpha oscillatory modulations are a correlate of visuospatial attention. Specifically, an enhancement of alpha power is observed in the ipsilateral posterior cortex to the locus of attention, along with a suppression in the contralateral hemisphere. An influential model proposes that the alpha enhancement is functionally related to the suppression of information. However, whether ipsilateral alpha power represents a mechanism through which no longer relevant WM representations are inhibited has yet not been explored. Here we examined whether the amount of distractors to be suppressed during WM maintenance is functionally related to alpha power lateralized activity. We measure EEG activity while participants (N = 36) performed a retro-cue task in which the WM load was varied across the relevant/irrelevant post-cue hemifield. We found that alpha activity was lateralized respect to the locus of attention, but did not track post-cue irrelevant load. Additionally, non-lateralized alpha activity increased with post-cue relevant load. We propose that alpha lateralization associated to retro-cuing might be related to a general orienting mechanism toward relevant representation. Copyright © 2018 Elsevier B.V. All rights reserved.
Statistical Power for the Comparative Regression Discontinuity Design With a Pretest No-Treatment Control Function: Theory and Evidence From the National Head Start Impact Study.

PubMed

Tang, Yang; Cook, Thomas D

2018-01-01

The basic regression discontinuity design (RDD) has less statistical power than a randomized control trial (RCT) with the same sample size. Adding a no-treatment comparison function to the basic RDD creates a comparative RDD (CRD); and when this function comes from the pretest value of the study outcome, a CRD-Pre design results. We use a within-study comparison (WSC) to examine the power of CRD-Pre relative to both basic RDD and RCT. We first build the theoretical foundation for power in CRD-Pre, then derive the relevant variance formulae, and finally compare them to the theoretical RCT variance. We conclude from this theoretical part of this article that (1) CRD-Pre's power gain depends on the partial correlation between the pretest and posttest measures after conditioning on the assignment variable, (2) CRD-Pre is less responsive than basic RDD to how the assignment variable is distributed and where the cutoff is located, and (3) under a variety of conditions, the efficiency of CRD-Pre is very close to that of the RCT. Data from the National Head Start Impact Study are then used to construct RCT, RDD, and CRD-Pre designs and to compare their power. The empirical results indicate (1) a high level of correspondence between the predicted and obtained power results for RDD and CRD-Pre relative to the RCT, and (2) power levels in CRD-Pre and RCT that are very close. The study is unique among WSCs for its focus on the correspondence between RCT and observational study standard errors rather than means.
An Empirical Assessment of the Form of Utility Functions

ERIC Educational Resources Information Center

Kirby, Kris N.

2011-01-01

Utility functions, which relate subjective value to physical attributes of experience, are fundamental to most decision theories. Seven experiments were conducted to test predictions of the most widely assumed mathematical forms of utility (power, log, and negative exponential), and a function proposed by Rachlin (1992). For pairs of gambles for…
Maximizing photovoltaic power generation of a space-dart configured satellite

NASA Astrophysics Data System (ADS)

Lee, Dae Young; Cutler, James W.; Mancewicz, Joe; Ridley, Aaron J.

2015-06-01

Many small satellites are power constrained due to their minimal solar panel area and the eclipse environment of low-Earth orbit. As with larger satellites, these small satellites, including CubeSats, use deployable power arrays to increase power production. This presents a design opportunity to develop various objective functions related to energy management and methods for optimizing these functions over a satellite design. A novel power generation model was created, and a simulation system was developed to evaluate various objective functions describing energy management for complex satellite designs. The model uses a spacecraft-body-fixed spherical coordinate system to analyze the complex geometry of a satellite's self-induced shadowing with computation provided by the Open Graphics Library. As an example design problem, a CubeSat configured as a space-dart with four deployable panels is optimized. Due to the fast computation speed of the solution, an exhaustive search over the design space is used to find the solar panel deployment angles which maximize total power generation. Simulation results are presented for a variety of orbit scenarios. The method is extendable to a variety of complex satellite geometries and power generation systems.
Defense Standardization Program Journal, July/December 2007

DTIC Science & Technology

2007-12-01

during the standard next review cycle, and identified areas where supplemental standards are needed. ENTERPRISE POWER SECURITY AND CONTINUITY Continual...availability of electric power at the enterprise level is essential for busi- ness functions, safety, and the public well-being.Yet many practical...challenges exist related to keeping critical operations, equipment, or facilities powered when the Peieeaeuiyivle ail ad acn teholg tatsnee electric grid is
Power, distress, and compassion: turning a blind eye to the suffering of others.

PubMed

van Kleef, Gerben A; Oveis, Christopher; van der Löwe, Ilmo; LuoKogan, Aleksandr; Goetz, Jennifer; Keltner, Dacher

2008-12-01

Responses to individuals who suffer are a foundation of cooperative communities. On the basis of the approach/inhibition theory of power (Keltner, Gruenfeld, & Anderson, 2003), we hypothesized that elevated social power is associated with diminished reciprocal emotional responses to another person's suffering (feeling distress at another person's distress) and with diminished complementary emotion (e.g., compassion). In face-to-face conversations, participants disclosed experiences that had caused them suffering. As predicted, participants with a higher sense of power experienced less distress and less compassion and exhibited greater autonomic emotion regulation when confronted with another participant's suffering. Additional analyses revealed that these findings could not be attributed to power-related differences in baseline emotion or decoding accuracy, but were likely shaped by power-related differences in the motivation to affiliate. Implications for theorizing about power and the social functions of emotions are discussed.
Evaluation of fire-safety programs that use 10-year smoke alarms.

PubMed

Jackson, Mark; Wilson, Jonathan; Akoto, Judith; Dixon, Sherry; Jacobs, David E; Ballesteros, Michael F

2010-10-01

The Centers for Disease Control and Prevention began funding a Smoke Alarm Installation and Fire Safety Education (SAIFE) program in 1998. This program involves the installation of lithium-powered "10-year" smoke alarms in homes at high risk for fires and injuries. This study aimed to (1) determine among original SAIFE homes if the lithium-powered alarms were still present and functional 8-10 years after installation and (2) understand factors related to smoke alarm presence and functionality. Data on a total of 384 homes and 601 smoke alarms in five states were collected and analyzed. Only one-third of alarms were still functional; 37% of installed alarms were missing; and 30% of alarms were present, but not functioning. Alarms were less likely to be functioning if they were installed in the kitchen and if homes had a different resident at follow-up. Of the 351 alarms that were present and had a battery at the time of the evaluation, only 21% contained lithium-powered batteries. Of these, 78% were still functioning. Programs that install lithium-powered alarms should use units that have sealed-in batteries and "hush" buttons. Additionally, education should be given on smoke alarm maintenance that includes a message that batteries in these alarms should not be replaced. Lithium-powered smoke alarms should last up to 10 years if maintained properly.
Spin properties of supermassive black holes with powerful outflows

NASA Astrophysics Data System (ADS)

Daly, Ruth. A.

2016-05-01

Relationships between beam power and accretion disc luminosity are studied for a sample of 55 high excitation radio galaxies (HERG), 13 low excitation radio galaxies (LERG), and 29 radio loud quasars (RLQ) with powerful outflows. The ratio of beam power to disc luminosity tends to be high for LERG, low for RLQ, and spans the full range of values for HERG. Writing general expressions for the disc luminosity and beam power and applying the empirically determined relationships allows a function that parametrizes the spins of the holes to be estimated. Interestingly, one of the solutions that is consistent with the data has a functional form that is remarkably similar to that expected in the generalized Blandford-Znajek model with a magnetic field that is similar in form to that expected in magnetically arrested disk (MAD) and advection-dominated accretion flow (ADAF) models. Values of the spin function, obtained independent of specific outflow models, suggest that spin and active galactic nucleus type are not related for these types of sources. The spin function can be used to solve for black hole spin in the context of particular outflow models, and one example is provided.
Research on intelligent power distribution system for spacecraft

NASA Astrophysics Data System (ADS)

Xia, Xiaodong; Wu, Jianju

2017-10-01

The power distribution system (PDS) mainly realizes the power distribution and management of the electrical load of the whole spacecraft, which is directly related to the success or failure of the mission, and hence is an important part of the spacecraft. In order to improve the reliability and intelligent degree of the PDS, and considering the function and composition of spacecraft power distribution system, this paper systematically expounds the design principle and method of the intelligent power distribution system based on SSPC, and provides the analysis and verification of the test data additionally.
Public Relations Manager Involvement in Strategic Issue Diagnosis.

ERIC Educational Resources Information Center

Lauzen, Martha M.

1995-01-01

Reports on an exploratory study that seeks to build theoretical understanding of how public relations practitioner involvement in one type of strategic organizational decision making--strategic issue diagnosis--is related to shared values with top management, diagnosis accuracy, strategy pursued, and the power of the public relations function. (TB)
A Within-subjects Experimental Protocol to Assess the Effects of Social Input on Infant EEG.

PubMed

St John, Ashley M; Kao, Katie; Chita-Tegmark, Meia; Liederman, Jacqueline; Grieve, Philip G; Tarullo, Amanda R

2017-05-03

Despite the importance of social interactions for infant brain development, little research has assessed functional neural activation while infants socially interact. Electroencephalography (EEG) power is an advantageous technique to assess infant functional neural activation. However, many studies record infant EEG only during one baseline condition. This protocol describes a paradigm that is designed to comprehensively assess infant EEG activity in both social and nonsocial contexts as well as tease apart how different types of social inputs differentially relate to infant EEG. The within-subjects paradigm includes four controlled conditions. In the nonsocial condition, infants view objects on computer screens. The joint attention condition involves an experimenter directing the infant's attention to pictures. The joint attention condition includes three types of social input: language, face-to-face interaction, and the presence of joint attention. Differences in infant EEG between the nonsocial and joint attention conditions could be due to any of these three types of input. Therefore, two additional conditions (one with language input while the experimenter is hidden behind a screen and one with face-to-face interaction) were included to assess the driving contextual factors in patterns of infant neural activation. Representative results demonstrate that infant EEG power varied by condition, both overall and differentially by brain region, supporting the functional nature of infant EEG power. This technique is advantageous in that it includes conditions that are clearly social or nonsocial and allows for examination of how specific types of social input relate to EEG power. This paradigm can be used to assess how individual differences in age, affect, socioeconomic status, and parent-infant interaction quality relate to the development of the social brain. Based on the demonstrated functional nature of infant EEG power, future studies should consider the role of EEG recording context and design conditions that are clearly social or nonsocial.
Optimizing the noise characteristics of high-power fiber laser systems

NASA Astrophysics Data System (ADS)

Jauregui, Cesar; Müller, Michael; Kienel, Marco; Emaury, Florian; Saraceno, Clara J.; Limpert, Jens; Keller, Ursula; Tünnermann, Andreas

2017-02-01

The noise characteristics of high-power fiber lasers, unlike those of other solid-state lasers such as thin-disks, have not been systematically studied up to now. However, novel applications for high-power fiber laser systems, such as attosecond pulse generation, put stringent limits to the maximum noise level of these sources. Therefore, in order to address these applications, a detailed knowledge and understanding of the characteristics of noise and its behavior in a fiber laser system is required. In this work we have carried out a systematic study of the propagation of the relative intensity noise (RIN) along the amplification chain of a state-of-the-art high-power fiber laser system. The most striking feature of these measurements is that the RIN level is progressively attenuated after each amplification stage. In order to understand this unexpected behavior, we have simulated the transfer function of the RIN in a fiber amplification stage ( 80μm core) as a function of the seed power and the frequency. Our simulation model shows that this damping of the amplitude noise is related to saturation. Additionally, we show, for the first time to the best of our knowledge, that the fiber design (e.g. core size, glass composition, doping geometry) can be modified to optimize the noise characteristics of high-power fiber laser systems.
Design and development of solar power-assisted manual/electric wheelchair.

PubMed

Chien, Chi-Sheng; Huang, Tung-Yung; Liao, Tze-Yuan; Kuo, Tsung-Yuan; Lee, Tzer-Min

2014-01-01

Wheelchairs are an essential assistive device for many individuals with injury or disability. Manual wheelchairs provide a relatively low-cost solution to the mobility needs of such individuals. Furthermore, they provide an effective means of improving the user's cardiopulmonary function and upper-limb muscle strength. However, manual wheelchairs have a loss gross mechanical efficiency, and thus the risk of user fatigue and upper-limb injury is increased. Electric-powered wheelchairs reduce the risk of injury and provide a more convenient means of transportation. However, they have a large physical size and are relatively expensive. Accordingly, the present study utilizes a quality function deployment method to develop a wheelchair with a user-selectable manual/electric propulsion mode and an auxiliary solar power supply system. The auxiliary solar power supply increased the travel range of the wheelchair by approximately 26% compared with that of a wheelchair powered by battery alone. Moreover, the wheelchair has a modular design and can be disassembled and folded for ease of transportation or storage. Overall, the present results suggest that the proposed wheelchair provides an effective and convenient means of meeting the mobility needs of individuals with mobility difficulties.
Functional Connectivity and Quantitative EEG in Women with Alcohol Use Disorders: A Resting-State Study.

PubMed

Herrera-Díaz, Adianes; Mendoza-Quiñones, Raúl; Melie-Garcia, Lester; Martínez-Montes, Eduardo; Sanabria-Diaz, Gretel; Romero-Quintana, Yuniel; Salazar-Guerra, Iraklys; Carballoso-Acosta, Mario; Caballero-Moreno, Antonio

2016-05-01

This study was aimed at exploring the electroencephalographic features associated with alcohol use disorders (AUD) during a resting-state condition, by using quantitative EEG and Functional Connectivity analyses. In addition, we explored whether EEG functional connectivity is associated with trait impulsivity. Absolute and relative powers and Synchronization Likelihood (SL) as a measure of functional connectivity were analyzed in 15 AUD women and fifteen controls matched in age, gender and education. Correlation analysis between self-report impulsivity as measured by the Barratt impulsiveness Scale (BIS-11) and SL values of AUD patients were performed. Our results showed increased absolute and relative beta power in AUD patients compared to matched controls, and reduced functional connectivity in AUD patients predominantly in the beta and alpha bands. Impaired connectivity was distributed at fronto-central and occipito-parietal regions in the alpha band, and over the entire scalp in the beta band. We also found that impaired functional connectivity particularly in alpha band at fronto-central areas was negative correlated with non-planning dimension of impulsivity. These findings suggest that functional brain abnormalities are present in AUD patients and a disruption of resting-state EEG functional connectivity is associated with psychopathological traits of addictive behavior.
Feasibility and acceptability of using jumping mechanography to detect early components of sarcopenia in community-dwelling older women

PubMed Central

Hannam, K.; Hartley, A.; Clark, E.M.; Sayer, A. Aihie; Tobias, J.H.; Gregson, C.L.

2017-01-01

Objective: To determine the feasibility and acceptability of using peak power and force, measured by jumping mechanography (JM), to detect early age-related features of sarcopenia in older women. Methods: Community-dwelling women aged 71-87 years were recruited into this cross-sectional study. Physical function tests comprised the short physical performance battery (SPPB), grip strength and, if SPPB score≥6, JM. JM measured peak weight-adjusted power and force from two-footed jumps and one-legged hops respectively. Questionnaires assessed acceptability. Results: 463 women were recruited; 37(8%) with SPPB<6 were ineligible for JM. Of 426 remaining, 359(84%) were able to perform ≥1 valid two-footed jump, 300(70%) completed ≥1 valid one-legged hop. No adverse events occurred. Only 14% reported discomfort. Discomfort related to JM performance, with inverse associations with both power and force (p<0.01). Peak power and force respectively explained 8% and 10% of variance in SPPB score (13% combined); only peak power explained additional variance in grip strength (17%). Conclusions: Peak power and force explained a significant, but limited, proportion of variance in SPPB and grip strength. JM represents a safe and acceptable clinical tool for evaluating lower-limb muscle power and force in older women, detecting distinct components of muscle function, and possibly sarcopenia, compared to those evaluated by more established measures. PMID:28860427

Using Analysis of Governance to Unpack Community-Based Conservation: A Case Study from Tanzania.

PubMed

Robinson, Lance W; Makupa, Enock

2015-11-01

Community-based conservation policies and programs are often hollow with little real devolution. But to pass a judgment of community-based or not community-based on such initiatives and programs obscures what is actually a suite of attributes. In this paper, we analyze governance around a specific case of what is nominally community-based conservation-Ikona Wildlife Management Area (WMA) in Tanzania-using two complementary sets of criteria. The first relates to governance "powers": planning powers, regulatory powers, spending powers, revenue-generating powers, and the power to enter into agreements. The second set of criteria derive from the understanding of governance as a set of social functions: social coordination, shaping power, setting direction, and building community. The analysis helps to detail ways in which the Tanzanian state through policy and regulations has constrained the potential for Ikona WMA to empower communities and community actors. Although it has some features of community-based conservation, community input into how the governance social functions would be carried out in the WMA was constrained from the start and is now largely out of community hands. The two governance powers that have any significant community-based flavor-spending powers and revenue-generating powers-relate to the WMA's tourism activities, but even here the picture is equivocal at best. The unpacking of governance that we have done, however, reveals that community empowerment through the processes associated with creating and recognizing indigenous and community-conserved areas is something that can be pursued through multiple channels, some of which might be more strategic than others.
Gain dynamics of clad-pumped Yb-fiber amplifier and intensity noise control.

PubMed

Zhao, Jian; Guiraud, Germain; Floissat, Florian; Gouhier, Benoit; Rota-Rodrigo, Sergio; Traynor, Nicholas; Santarelli, Giorgio

2017-01-09

Gain dynamics study provides an attractive method to understand the intensity noise behavior in fiber amplifiers. Here, the gain dynamics of a medium power (5 W) clad-pumped Yb-fiber amplifier is experimentally evaluated by measuring the frequency domain transfer functions for the input seed and pump lasers from 10 Hz to 1 MHz. We study gain dynamic behavior of the fiber amplifier in the presence of significant residual pump power (compared to the seed power), showing that the seed transfer function is strongly saturated at low Fourier frequencies while the pump power modulation transfer function is nearly unaffected. The characterization of relative intensity noise (RIN) of the fiber amplifier is well explained by the gain dynamics analysis. Finally, a 600 kHz bandwidth feedback loop using an acoustic-optical modulator (AOM) controlling the seed intensity is successfully demonstrated to suppress the broadband laser intensity noise. A maximum noise reduction of about 30 dB is achieved leading to a RIN of -152 dBc/Hz (~1 kHz-10 MHz) at 2.5 W output power.
Analytic approximations to the modon dispersion relation. [in oceanography

NASA Technical Reports Server (NTRS)

Boyd, J. P.

1981-01-01

Three explicit analytic approximations are given to the modon dispersion relation developed by Flierl et al. (1980) to describe Gulf Stream rings and related phenomena in the oceans and atmosphere. The solutions are in the form of k(q), and are developed in the form of a power series in q for small q, an inverse power series in 1/q for large q, and a two-point Pade approximant. The low order Pade approximant is shown to yield a solution for the dispersion relation with a maximum relative error for the lowest branch of the function equal to one in 700 in the q interval zero to infinity.
Poor Response Inhibition as a Predictor of Problem Drinking and Illicit Drug Use in Adolescents at Risk for Alcoholism and Other Substance Use Disorders

ERIC Educational Resources Information Center

Nigg, Joel T.; Wong, Maria M.; Martel, Michelle M.; Jester, Jennifer M.; Puttler, Leon I.; Glass, Jennifer M.; Adams, Kenneth M.; Fitzgerald, Hiram E.; Zucker, Robert A.

2006-01-01

Objective: To evaluate the predictive power of executive functions, in particular, response inhibition, in relation to alcohol-related problems and illicit drug use in adolescence. Method: A total of 498 children from 275 families from a longitudinal high-risk study completed executive function measures in early and late adolescence and lifetime…
Cycling Power Outputs Predict Functional Threshold Power And Maximum Oxygen Uptake.

PubMed

Denham, Joshua; Scott-Hamilton, John; Hagstrom, Amanda D; Gray, Adrian J

2017-09-11

Functional threshold power (FTP) has emerged as a correlate of lactate threshold and is commonly assessed by recreational and professional cyclists for tailored exercise programing. To identify whether results from traditional aerobic and anaerobic cycling tests could predict FTP and V˙ O2max, we analysed the association between estimated FTP, maximum oxygen uptake (V˙ O2max [mlkgmin]) and power outputs obtained from a maximal cycle ergometry cardiopulmonary exercise test (CPET) and a 30-s Wingate test in a heterogeneous cohort of cycle-trained and untrained individuals (N=40, mean±SD; age: 32.6±10.6 y; relative V˙ O2max: 46.8±9.1 mlkgmin). The accuracy and sensitivity of the prediction equations was also assessed in young men (N=11) before and after a 6-wk sprint interval training intervention.Moderate to strong positive correlations were observed between FTP, relative V˙ O2max and power outputs achieved during incremental and 30-s Wingate cycling tests (r=.39-.965, all P<.05). While maximum power achieved during incremental cycle testing (Pmax) and relative V˙ O2max were predictors of FTP (r =.93), age and FTP (Wkg) estimated relative V˙ O2max (r=.80). Our findings confirm that FTP predominantly relies on aerobic metabolism and indicate both prediction models are sensitive enough to detect meaningful exercise-induced changes in FTP and V˙ O2max. Thus, coaches should consider limiting the time and load demands placed on athletes by conducting a maximal cycle ergometry CPET to estimate FTP. Additionally, a 20-min FTP test is a convenient method to assess V˙ O2max and is particularly relevant for exercise professionals without access to expensive CPET equipment.
An Experiment on Salience as a Function of the Discriminatory Power of an Attribute.

ERIC Educational Resources Information Center

Finn, Michael S.

Carter's model of affective relations (1965) and Chaffee's research on cognitive discrepancies and communication (1959) are used to test the hypotheses that increasing an attribute's discriminatory power will increase attribute salience and that increasing the exclusiveness of an object's attributes will increase objective salience. The current…
A Lost Opportunity? Vocational Education in Physical Education

ERIC Educational Resources Information Center

Brown, Seth Earl; Macdonald, Doune

2011-01-01

Background: Vocational education in Australia and elsewhere has a history of being gendered and classed, thereby limiting the post-school options of students undertaking this form of study. Drawing on Foucauldian theory, the authors used Gore's eight techniques of power to examine the micro-functioning of power relations at two case sites.…
10 CFR 830 Major Modification Determination for the ATR Diesel Bus (E-3) and Switchgear Replacement

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

Noel Duckwtiz

2011-05-01

Near term replacement of aging and obsolescent original ATR equipment has become important to ensure ATR capability in support of NE’s long term national missions. To that end, a mission needs statement has been prepared for a non-major system acquisition which is comprised of three interdependent subprojects. The first project, subject of this determination, will replace the existent diesel-electrical bus (E-3) and associated switchgear. More specifically, INL proposes transitioning ATR to 100% commercial power with appropriate emergency backup to include: • Provide commercial power as the normal source of power to the ATR loads currently supplied by diesel-electric power. •more » Provide backup power to the critical ATR loads in the event of a loss of commercial power. • Replace obsolescent critical ATR power distribution equipment, e.g., switchgear, transformers, motor control centers, distribution panels. Completion of this and two other age-related projects (primary coolant pump and motor replacement and emergency firewater injection system replacement) will resolve major age related operational issues plus make a significant contribution in sustaining the ATR safety and reliability profile. The major modification criteria evaluation of the project pre-conceptual design identified several issues make the project a major modification: 1. Evaluation Criteria #2 (Footprint change). The addition of a new PC-4 structure to the ATR Facility to house safety-related SSCs requires careful attention to maintaining adherence to applicable engineering and nuclear safety design criteria (e.g., structural qualification, fire suppression) to ensure no adverse impacts to the safety-related functions of the housed equipment. 2. Evaluation Criteria #3 (Change of existing process). The change to the strategy for providing continuous reliable power to the safety-related emergency coolant pumps requires careful attention and analysis to ensure it meets a project primary object to maintain or reduce CDF and does not negatively affect the efficacy of the currently approved strategy. 3. Evaluation Criteria #5 (Create the need for new or revised safety SSCs). The change to the strategy for providing continuous reliable power to the safety-related emergency coolant pumps, based on the pre-conceptual design, will require the addition of two quick start diesel generators, their associated power coordination/distribution controls, and a UPS to the list of safety-related SSCs. Similarly to item 1 above, the addition of these active SSCs to the list of safety-related SSCs and replacement of the E-3 bus requires careful attention to maintaining adherence to applicable engineering and nuclear safety design criteria (e.g., seismic qualification, isolation of redundant trains from common fault failures) to ensure no adverse impacts to the safety-related functions.« less
Conditional quantum entropy power inequality for d-level quantum systems

NASA Astrophysics Data System (ADS)

Jeong, Kabgyun; Lee, Soojoon; Jeong, Hyunseok

2018-04-01

We propose an extension of the quantum entropy power inequality for finite dimensional quantum systems, and prove a conditional quantum entropy power inequality by using the majorization relation as well as the concavity of entropic functions also given by Audenaert et al (2016 J. Math. Phys. 57 052202). Here, we make particular use of the fact that a specific local measurement after a partial swap operation (or partial swap quantum channel) acting only on finite dimensional bipartite subsystems does not affect the majorization relation for the conditional output states when a separable ancillary subsystem is involved. We expect our conditional quantum entropy power inequality to be useful, and applicable in bounding and analyzing several capacity problems for quantum channels.
Age-related changes in neocortical high-voltage spindles and alpha EEG power during quiet waking in rats.

PubMed

Moyanova, Slavianka G; Kirov, Roumen K; Kortenska, Lidia V

2002-04-01

Age-related changes in neocortical high-voltage spindle (HVS) and in electroencephalographic (EEG) alpha power were examined in young (3.0 to 4.6 months), middle-aged (10.2 to 13.8 months), and old (21.5 to 24.0 months) male Wistar rats during quiet waking. Whereas the duration of quiet waking stage did not change as a function of age, a significant increase in HVS amount and EEG alpha peak power was observed in the middle-aged rats with only a tendency for a further enhancement in the old animals. An additional analysis showed that the elevation of alpha power is associated with age rather than with HVS activity.
Bypass diode integration

NASA Technical Reports Server (NTRS)

Shepard, N. F., Jr.

1981-01-01

Protective bypass diodes and mounting configurations which are applicable for use with photovoltaic modules having power dissipation requirements in the 5 to 50 watt range were investigated. Using PN silicon and Schottky diode characterization data on packaged diodes and diode chips, typical diodes were selected as representative for each range of current carrying capacity, an appropriate heat dissipating mounting concept along with its environmental enclosure was defined, and a thermal analysis relating junction temperature as a function of power dissipation was performed. In addition, the heat dissipating mounting device dimensions were varied to determine the effect on junction temperature. The results of the analysis are presented as a set of curves indicating junction temperature as a function of power dissipation for each diode package.
Aging Wiener-Khinchin theorem and critical exponents of 1/f^{β} noise.

PubMed

Leibovich, N; Dechant, A; Lutz, E; Barkai, E

2016-11-01

The power spectrum of a stationary process may be calculated in terms of the autocorrelation function using the Wiener-Khinchin theorem. We here generalize the Wiener-Khinchin theorem for nonstationary processes and introduce a time-dependent power spectrum 〈S_{t_{m}}(ω)〉 where t_{m} is the measurement time. For processes with an aging autocorrelation function of the form 〈I(t)I(t+τ)〉=t^{Υ}ϕ_{EA}(τ/t), where ϕ_{EA}(x) is a nonanalytic function when x is small, we find aging 1/f^{β} noise. Aging 1/f^{β} noise is characterized by five critical exponents. We derive the relations between the scaled autocorrelation function and these exponents. We show that our definition of the time-dependent spectrum retains its interpretation as a density of Fourier modes and discuss the relation to the apparent infrared divergence of 1/f^{β} noise. We illustrate our results for blinking-quantum-dot models, single-file diffusion, and Brownian motion in a logarithmic potential.
Recent Technology of Sensing, Monitoring, Diagnosis, and Maintenance for Aged Electric Power and Energy System

NASA Astrophysics Data System (ADS)

Matsumoto, Satoshi

This paper deals with the recent topics related to sensing, monitoring, and diagnosis for electric power equipment. Moreover the risk management for such equipments has been an object of study in many terms such as economical, technical aspects, safety and rest, CSR (Corporate Social Responsibility) etc. The relationship between the function of the economic engineering and the maintenance strategy for electric power system are reviewed.
Effects of temperature on power output and contraction kinetics in the locomotor muscle of the regionally endothermic common thresher shark (Alopias vulpinus).

PubMed

Donley, Jeanine M; Sepulveda, Chugey A; Aalbers, Scott A; McGillivray, David G; Syme, Douglas A; Bernal, Diego

2012-10-01

The common thresher shark (Alopias vulpinus) is a pelagic species with medially positioned red aerobic swimming musculature (RM) and regional RM endothermy. This study tested whether the contractile characteristics of the RM are functionally similar along the length of the body and assessed how the contractile properties of the common thresher shark compare with those of other sharks. Contractile properties of the RM were examined at 8, 16 and 24 °C from anterior and posterior axial positions (0.4 and 0.6 fork length, respectively) using the work loop technique. Experiments were performed to determine whether the contractile properties of the RM are similar along the body of the common thresher shark and to document the effects of temperature on muscle power. Axial differences in contractile properties of RM were found to be small or absent. Isometric twitch kinetics of RM were ~fivefold slower than those of white muscle, with RM twitch durations of about 1 s at 24 °C and exceeding 5 s at 8 °C, a Q(10) of nearly 2.5. Power increased approximately tenfold with the 16 °C increase in temperature, while the cycle frequency for maximal power only increased from about 0.5-1.0 Hz over this temperature range. These data support the hypothesis that the RM is functionally similar along the body of the common thresher shark and corroborate previous findings from shark species both with and without medial RM. While twitch kinetics suggest the endothermic RM is not unusually temperature sensitive, measures of power suggest that the RM is not well suited to function at cool temperatures. The cycle frequency at which power is maximized appeared relatively insensitive to temperature in RM, which may reflect the relatively cooler temperature of the thresher RM compared to that observed in lamnid sharks as well as the relatively slow RM phenotype in these large fish.
Relationship between Functional Movement Screen and Some Athletic Abilities in Karate Athletes

ERIC Educational Resources Information Center

Yildiz, Suat

2018-01-01

In karate athletes, quality of movement and trunk control are important factors. Power output that is performed in short time requires functional movement capabilities. It's quite important to know that which athletic abilities are related to functional movement. Due to this concern, the aim of the study was to examine relationship between…
Relationships Among Lower Body Strength, Power, and Performance of Functional Tasks

NASA Technical Reports Server (NTRS)

Ploutz-Snyder, Lori; Ryder, J.; Hackney, K.; Scott-Pandorf, M.; Redd, E.; Buxton, R.; Bloomberg, J.

2010-01-01

There is a large degree of variability among crewmembers with respect to decrements in muscle strength and power following long duration spaceflight, ranging from 0 to approx.30% reductions. The purpose of this study was to investigate the influence of varying decrements in lower body muscle strength and power (relative to body weight) on the performance of 2 occupationally relevant tasks (ladder climb and supine egress & walk). Seventeen participants with leg strength similar to US crewmembers performed a leg press power test, an isokinetic knee extension strength test and they were asked to complete the 2 functional tasks as quickly as possible. On additional test days the participants were asked to repeat the functional tasks under 3 conditions where a different external load was applied each time using a weighted suit in order to experimentally manipulate participants strength/body weight and power/body weight ratios. The weight in the suit ranged from 20-120% of body weight and was distributed in proportion to limb segment weights to minimize changes in center of gravity. The ladder task consisted of climbing 40 rungs on a ladder treadmill as fast as possible. The supine egress & walk task consisted of rising from a supine position and walking through an obstacle course. Results show a relatively linear relationship between strength/body weight and task time and power/body weight with task time such that the fastest performance times are associated with higher strength and power with about half the variance in task time is accounted for by a single variable (either strength or power). For the average person, a 20% reduction in power/body weight (from 18 to 14.4 W/kg) induces an increase (slowing) of about 10 seconds in the ladder climb task from 14 to 24 seconds (approx.70%) and a slowing of the supine egress & walk task from 14 to 21 seconds (approx.50%). Similar relationships were observed with strength/body weight and task performance. For the average person, a 20% reduction in strength/body weight (from 2.1 to 1.7 Nm/kg) resulted in a slowing of the ladder climb from 10.5 to 24 seconds (approx.128%) and a slowing of the supine egress & walk from 11 to 20 seconds (approx.82%). These data suggest that the single variable of either low body muscle strength or power, relative to body weight is predictive of about 50% of the variance in task performance time, and that considerable slowing in task performance is associated with relatively typical decrements in muscle performance seen with long duration spaceflight. The observation of a relatively linear relationship between strength/power and task time suggests that across the full spectrum of initial crew strengths and typical decrements in strength previously observed, that task performance would be expected to be slowed following long duration spaceflight. These data will be confirmed in actual spaceflight with subsequent studies.
Solar wind control of auroral zone geomagnetic activity

NASA Technical Reports Server (NTRS)

Clauer, C. R.; Mcpherron, R. L.; Searls, C.; Kivelson, M. G.

1981-01-01

Solar wind magnetosphere energy coupling functions are analyzed using linear prediction filtering with 2.5 minute data. The relationship of auroral zone geomagnetic activity to solar wind power input functions are examined, and a least squares prediction filter, or impulse response function is designed from the data. Computed impulse response functions are observed to have characteristics of a low pass filter with time delay. The AL index is found well related to solar wind energy functions, although the AU index shows a poor relationship. High frequency variations of auroral indices and substorm expansions are not predictable with solar wind information alone, suggesting influence by internal magnetospheric processes. Finally, the epsilon parameter shows a poorer relationship with auroral geomagnetic activity than a power parameter, having a VBs solar wind dependency.
Encircling the dark: constraining dark energy via cosmic density in spheres

NASA Astrophysics Data System (ADS)

Codis, S.; Pichon, C.; Bernardeau, F.; Uhlemann, C.; Prunet, S.

2016-08-01

The recently published analytic probability density function for the mildly non-linear cosmic density field within spherical cells is used to build a simple but accurate maximum likelihood estimate for the redshift evolution of the variance of the density, which, as expected, is shown to have smaller relative error than the sample variance. This estimator provides a competitive probe for the equation of state of dark energy, reaching a few per cent accuracy on wp and wa for a Euclid-like survey. The corresponding likelihood function can take into account the configuration of the cells via their relative separations. A code to compute one-cell-density probability density functions for arbitrary initial power spectrum, top-hat smoothing and various spherical-collapse dynamics is made available online, so as to provide straightforward means of testing the effect of alternative dark energy models and initial power spectra on the low-redshift matter distribution.
Explanation of power law behavior of autoregressive conditional duration processes based on the random multiplicative process

NASA Astrophysics Data System (ADS)

Sato, Aki-Hiro

2004-04-01

Autoregressive conditional duration (ACD) processes, which have the potential to be applied to power law distributions of complex systems found in natural science, life science, and social science, are analyzed both numerically and theoretically. An ACD(1) process exhibits the singular second order moment, which suggests that its probability density function (PDF) has a power law tail. It is verified that the PDF of the ACD(1) has a power law tail with an arbitrary exponent depending on a model parameter. On the basis of theory of the random multiplicative process a relation between the model parameter and the power law exponent is theoretically derived. It is confirmed that the relation is valid from numerical simulations. An application of the ACD(1) to intervals between two successive transactions in a foreign currency market is shown.
Explanation of power law behavior of autoregressive conditional duration processes based on the random multiplicative process.

PubMed

Sato, Aki-Hiro

2004-04-01

Autoregressive conditional duration (ACD) processes, which have the potential to be applied to power law distributions of complex systems found in natural science, life science, and social science, are analyzed both numerically and theoretically. An ACD(1) process exhibits the singular second order moment, which suggests that its probability density function (PDF) has a power law tail. It is verified that the PDF of the ACD(1) has a power law tail with an arbitrary exponent depending on a model parameter. On the basis of theory of the random multiplicative process a relation between the model parameter and the power law exponent is theoretically derived. It is confirmed that the relation is valid from numerical simulations. An application of the ACD(1) to intervals between two successive transactions in a foreign currency market is shown.

Examining the mediating effect of supervisor conflict on procedural injustice-job strain relations: the function of power distance.

PubMed

Liu, Cong; Yang, Liu-Qin; Nauta, Margaret M

2013-01-01

The present study examined the associations among procedural injustice, conflict with a supervisor (supervisor conflict), and job strains for employees with different power distance orientations. Using data from 301 university employees, along with corroborative reports from a coworker of each employee, we tested a moderated mediation model in which the indirect effect of procedural injustice on job strains (e.g., anxiety and depression) through supervisor conflict was conditional upon employees' power distance orientation. We found perceived procedural injustice was positively related to supervisor conflict, and this relation was moderated by employees' power distance orientation (as supported by both self- and coworker-reported conflict data). The pattern of the moderating effect indicated the positive relation between procedural injustice and supervisor conflict was only significant among employees with low to moderate power distance orientations. As expected, supervisor conflict served as the underlying mechanism linking perceived procedural injustice and employees' anxiety/depression (as supported by self-reported conflict data). The mediating effect of supervisor conflict was significant for employees with low to moderate power distance orientations but not for employees with high power distance orientation. This study broadens the focus of research on supervisor conflict and presents a more complex model of how perceived injustice influences employees' job strains than is currently available in the literature.
A Note on Comparing the Power of Test Statistics at Low Significance Levels.

PubMed

Morris, Nathan; Elston, Robert

2011-01-01

It is an obvious fact that the power of a test statistic is dependent upon the significance (alpha) level at which the test is performed. It is perhaps a less obvious fact that the relative performance of two statistics in terms of power is also a function of the alpha level. Through numerous personal discussions, we have noted that even some competent statisticians have the mistaken intuition that relative power comparisons at traditional levels such as α = 0.05 will be roughly similar to relative power comparisons at very low levels, such as the level α = 5 × 10 -8 , which is commonly used in genome-wide association studies. In this brief note, we demonstrate that this notion is in fact quite wrong, especially with respect to comparing tests with differing degrees of freedom. In fact, at very low alpha levels the cost of additional degrees of freedom is often comparatively low. Thus we recommend that statisticians exercise caution when interpreting the results of power comparison studies which use alpha levels that will not be used in practice.
Geometric description of a discrete power function associated with the sixth Painlevé equation.

PubMed

Joshi, Nalini; Kajiwara, Kenji; Masuda, Tetsu; Nakazono, Nobutaka; Shi, Yang

2017-11-01

In this paper, we consider the discrete power function associated with the sixth Painlevé equation. This function is a special solution of the so-called cross-ratio equation with a similarity constraint. We show in this paper that this system is embedded in a cubic lattice with [Formula: see text] symmetry. By constructing the action of [Formula: see text] as a subgroup of [Formula: see text], i.e. the symmetry group of P VI , we show how to relate [Formula: see text] to the symmetry group of the lattice. Moreover, by using translations in [Formula: see text], we explain the odd-even structure appearing in previously known explicit formulae in terms of the τ function.
Relationship between alcohol-related expectancies and anterior brain functioning in young men at risk for developing alcoholism.

PubMed

Deckel, A W; Hesselbrock, V; Bauer, L

1995-04-01

This experiment examined the relationship between anterior brain functioning and alcohol-related expectancies. Ninety-one young men at risk for developing alcoholism were assessed on the Alcohol Expectancy Questionnaire (AEQ) and administered neuropsychological and EEG tests. Three of the scales on the AEQ, including the "Enhanced Sexual Functioning" scale, the "Increased Social Assertiveness" scale, and items from the "Global/Positive Change scale," were used, because each of these scales has been found to discriminate alcohol-based expectancies adequately by at least two separate sets of investigators. Regression analysis found that anterior neuropsychological tests (including the Wisconsin Card Sorting test, the Porteus Maze test, the Controlled Oral Word Fluency test, and the Luria-Nebraska motor functioning tests) were predictive of the AEQ scale scores on regression analysis. One of the AEQ scales, "Enhanced Sexual Functioning," was also predicted by WAIS-R-Verbal scales, whereas the "Global/Positive" AEQ scale was predicted by the WAIS-R Performance scales. Regression analysis using EEG power as predictors found that left versus right hemisphere "difference" scores obtained from frontal EEG leads were predictive of the three AEQ scales. Conversely, parietal EEG power did not significantly predict any of the expectancy scales. It is concluded that anterior brain any of the expectancy scales. It is concluded that anterior brain functioning is associated with alcohol-related expectancies. These findings suggest that alcohol-related expectancy may be, in part, biologically determined by frontal/prefrontal systems, and that dysfunctioning in these systems may serve as a risk factor for the development of alcohol-related behaviors.
Neurodevelopmental differences to social exclusion: An event-related neural oscillation study of children, adolescents, and adults.

PubMed

Tang, Alva; Lahat, Ayelet; Crowley, Michael J; Wu, Jia; Schmidt, Louis A

2018-05-21

Although the neural correlates of social exclusion have been well-documented, most studies have examined single age groups. No studies have directly compared specific age-related differences in social exclusion across children, adolescents, and adults using event-related oscillatory electroencephalogram (EEG) dynamics. The authors examined event-related theta EEG power and phase coherence in fair play and social exclusion conditions during the Cyberball task in 166 participants: 42 children (ages 10-12), 56 adolescents (ages 14-17), and 68 adults (ages 18-28). Children and adolescents displayed the greatest theta power to rejection events, whereas adults displayed the greatest theta power to "not my turn" events. Moreover, the functional link between theta power to rejection and self-reported distress was strongest among the adolescents. These findings suggest that an enhanced neural response to social exclusion is present by preadolescence, but the association between neural and subjective responses is most prominent during adolescence. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
40 CFR 142.76 - Request by an Indian Tribe for a determination of eligibility.

Code of Federal Regulations, 2010 CFR

2010-07-01

... functions currently performed by the Tribal governing body such as, but not limited to, the exercise of police powers affecting (or relating to) the health, safety, and welfare of the affected population; taxation; and the exercise of the power of eminent domain; and (3) Identify the sources of the Tribal...
Physical activity as intervention for age-related loss of muscle mass and function: protocol for a randomised controlled trial (the LISA study)

PubMed Central

Eriksen, Christian Skou; Garde, Ellen; Reislev, Nina Linde; Wimmelmann, Cathrine Lawaetz; Bieler, Theresa; Ziegler, Andreas Kraag; Gylling, Anne Theil; Dideriksen, Kasper Juel; Siebner, Hartwig Roman; Mortensen, Erik Lykke; Kjaer, Michael

2016-01-01

Introduction Physical and cognitive function decline with age, accelerating during the 6th decade. Loss of muscle power (force×velocity product) is a dominant physical determinant for loss of functional ability, especially if the lower extremities are affected. Muscle strength training is known to maintain or even improve muscle power as well as physical function in older adults, but the optimal type of training for beneficial long-term training effects over several years is unknown. Moreover, the impact of muscle strength training on cognitive function and brain structure remains speculative. The primary aim of this randomised controlled trial is to compare the efficacy of two different 1 year strength training regimens on immediate and long-lasting improvements in muscle power in retirement-age individuals. Secondary aims are to evaluate the effect on muscle strength, muscle mass, physical and cognitive function, mental well-being, health-related quality of life and brain morphology. Methods and analysis The study includes 450 home-dwelling men and women (62–70 years). Participants are randomly allocated to (1) 1 year of supervised, centre-based heavy resistance training, (2) home-based moderate intensity resistance training or (3) habitual physical activity (control). Changes in primary (leg extensor power) and secondary outcomes are analysed according to the intention to treat principle and per protocol at 1, 2, 4, 7 and 10 years. Ethics and dissemination The study is expected to generate new insights into training-induced promotion of functional ability and independency after retirement and will help to formulate national recommendations regarding physical activity schemes for the growing population of older individuals in western societies. Results will be published in scientific peer-reviewed journals, in PhD theses and at public meetings. The study is approved by the Regional Ethical Committee (Capital Region, Copenhagen, Denmark, number H-3-2014-017). Trial registration number NCT02123641. PMID:27913559
Primordial power spectrum features and consequences

NASA Astrophysics Data System (ADS)

Goswami, G.

2014-03-01

The present Cosmic Microwave Background (CMB) temperature and polarization anisotropy data is consistent with not only a power law scalar primordial power spectrum (PPS) with a small running but also with the scalar PPS having very sharp features. This has motivated inflationary models with such sharp features. Recently, even the possibility of having nulls in the power spectrum (at certain scales) has been considered. The existence of these nulls has been shown in linear perturbation theory. What shall be the effect of higher order corrections on such nulls? Inspired by this question, we have attempted to calculate quantum radiative corrections to the Fourier transform of the 2-point function in a toy field theory and address the issue of how these corrections to the power spectrum behave in models in which the tree-level power spectrum has a sharp dip (but not a null). In particular, we have considered the possibility of the relative enhancement of radiative corrections in a model in which the tree-level spectrum goes through a dip in power at a certain scale. The mode functions of the field (whose power spectrum is to be evaluated) are chosen such that they undergo the kind of dynamics that leads to a sharp dip in the tree level power spectrum. Next, we have considered the situation in which this field has quartic self interactions, and found one loop correction in a suitably chosen renormalization scheme. Thus, we have attempted to answer the following key question in the context of this toy model (which is as important in the realistic case): In the chosen renormalization scheme, can quantum radiative corrections be enhanced relative to tree-level power spectrum at scales, at which sharp dips appear in the tree-level spectrum?
Collective Human Mobility Pattern from Taxi Trips in Urban Area

PubMed Central

Peng, Chengbin; Jin, Xiaogang; Wong, Ka-Chun; Shi, Meixia; Liò, Pietro

2012-01-01

We analyze the passengers' traffic pattern for 1.58 million taxi trips of Shanghai, China. By employing the non-negative matrix factorization and optimization methods, we find that, people travel on workdays mainly for three purposes: commuting between home and workplace, traveling from workplace to workplace, and others such as leisure activities. Therefore, traffic flow in one area or between any pair of locations can be approximated by a linear combination of three basis flows, corresponding to the three purposes respectively. We name the coefficients in the linear combination as traffic powers, each of which indicates the strength of each basis flow. The traffic powers on different days are typically different even for the same location, due to the uncertainty of the human motion. Therefore, we provide a probability distribution function for the relative deviation of the traffic power. This distribution function is in terms of a series of functions for normalized binomial distributions. It can be well explained by statistical theories and is verified by empirical data. These findings are applicable in predicting the road traffic, tracing the traffic pattern and diagnosing the traffic related abnormal events. These results can also be used to infer land uses of urban area quite parsimoniously. PMID:22529917
Estimation of the EEG power spectrum using MRI T(2) relaxation time in traumatic brain injury.

PubMed

Thatcher, R W; Biver, C; Gomez, J F; North, D; Curtin, R; Walker, R A; Salazar, A

2001-09-01

To study the relationship between magnetic resonance imaging (MRI) T(2) relaxation time and the power spectrum of the electroencephalogram (EEG) in long-term follow up of traumatic brain injury. Nineteen channel quantitative electroencephalograms or qEEG, tests of cognitive function and quantitative MRI T(2) relaxation times (qMRI) were measured in 18 mild to severe closed head injured outpatients 2 months to 4.6 years after injury and 11 normal controls. MRI T(2) and the Laplacian of T(2) were then correlated with the power spectrum of the scalp electrical potentials and current source densities of the qEEG. qEEG and qMRI T(2) were related by a frequency tuning with maxima in the alpha (8-12Hz) and the lower EEG frequencies (0.5-5Hz), which varied as a function of spatial location. The Laplacian of T(2) acted like a spatial-temporal "lens" by increasing the spatial-temporal resolution of correlation between 3-dimensional T(2) and the ear referenced alert but resting spontaneous qEEG. The severity of traumatic brain injury can be modeled by a linear transfer function that relates the molecular qMRI to qEEG resonant frequencies.
Home closure as a weapon in the Dutch war on drugs: Does judicial review function as a safety net?

PubMed

Bruijn, L Michelle; Vols, Michel; Brouwer, Jan G

2018-01-01

A widespread sense of a failing criminal justice system and increased feelings of insecurity changed the response to crime into a culture of control, which is characterized by policies that punish and exclude. In the Netherlands, these influences can be witnessed in the war on drugs where local authorities use their administrative power to close homes involved in drug-related crime. Citizens can invoke judicial review over these administrative interferences by claiming that such closure results in an unfair balance between purposes, means and consequences. This paper assesses whether judicial review functions as a safety net against losing one's home due to drug-related crime. We used doctrinal legal research methods to examine the "law in the books" and empirical legal research methods to analyse the "law in action". We used a survey to investigate how often the drug-related closure power was used in 2015, and we statistically analysed all published case law of Dutch lower courts between 2007 and 2016. The scope of the closure power broadened over the years and our data show that local authorities fiercely make use of this instrument. In 41.4% of the cases, citizens are successful in fighting the closure. While scholarly literature indicates that judicial courts function as safeguards by questioning the proportionality of administrative action, raising a proportionality defence does not necessarily result in a more favourable outcome for citizens. In fact, raising a proportionality defence makes it more likely to result in dismissal of the appeal. The stretched scope of the drug-related closure power together with the relatively low success rate of citizens who fight the loss of their home and a seemingly meaningless proportionality check show no sign of a safety net against the loss of one's home at the suit of a local authority. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.
A density functional theory study of the role of functionalized graphene particles as effective additives in power cable insulation

PubMed Central

Song, Shuwei; Zhao, Hong; Zheng, Xiaonan; Zhang, Hui; Wang, Ying; Han, Baozhong

2018-01-01

The role of a series of functionalized graphene additives in power cable insulation in suppressing the growth of electrical treeing and preventing the degradation of the polymer matrix has been investigated by density functional theory calculations. Bader charge analysis indicates that pristine, doped or defect graphene could effectively capture hot electrons to block their attack on cross-linked polyethylene (XLPE) because of the π–π conjugated unsaturated structures. Further exploration of the electronic properties in the interfacial region between the additives and XLPE shows that N-doped single-vacancy graphene, graphene oxide and B-, N-, Si- or P-doped graphene oxide have relatively strong physical interaction with XLPE to restrict its mobility and rather weak chemical activity to prevent the cleavage of the C–H or C–C bond, suggesting that they are all potential candidates as effective additives. The understanding of the features of functionalized graphene additives in trapping electrons and interfacial interaction will assist in the screening of promising additives as voltage stabilizers in power cables. PMID:29515821
A density functional theory study of the role of functionalized graphene particles as effective additives in power cable insulation.

PubMed

Song, Shuwei; Zhao, Hong; Zheng, Xiaonan; Zhang, Hui; Liu, Yang; Wang, Ying; Han, Baozhong

2018-02-01

The role of a series of functionalized graphene additives in power cable insulation in suppressing the growth of electrical treeing and preventing the degradation of the polymer matrix has been investigated by density functional theory calculations. Bader charge analysis indicates that pristine, doped or defect graphene could effectively capture hot electrons to block their attack on cross-linked polyethylene (XLPE) because of the π-π conjugated unsaturated structures. Further exploration of the electronic properties in the interfacial region between the additives and XLPE shows that N-doped single-vacancy graphene, graphene oxide and B-, N-, Si- or P-doped graphene oxide have relatively strong physical interaction with XLPE to restrict its mobility and rather weak chemical activity to prevent the cleavage of the C-H or C-C bond, suggesting that they are all potential candidates as effective additives. The understanding of the features of functionalized graphene additives in trapping electrons and interfacial interaction will assist in the screening of promising additives as voltage stabilizers in power cables.
EEG activity during estral cycle in the rat.

PubMed

Corsi-Cabrera, M; Juárez, J; Ponce-de-León, M; Ramos, J; Velázquez, P N

1992-10-01

EEG activity was recorded from right and left parietal cortex in adult female rats daily during 6 days. Immediately after EEG recording vaginal smears were taken and were microscopically analyzed to determine the estral stage. Absolute and relative powers and interhemispheric correlation of EEG activity were calculated and compared between estral stages. Interhemispheric correlation was significantly lower during diestrous as compared to proestrous and estrous. Absolute and relative powers did not show significant differences between estral stages. Absolute powers of alpha1, alpha2, beta1 and beta2 bands were significantly higher at the right parietal cortex. Comparisons of the same EEG records with estral stages randomly grouped showed no significant differences for any of the EEG parameters. EEG activity is a sensitive tool to study functional changes related to the estral cycle.
Quantifying the linear and nonlinear relations between the urban form fragmentation and the carbon emission distribution

NASA Astrophysics Data System (ADS)

Zuo, S.; Dai, S.; Ren, Y.; Yu, Z.

2017-12-01

Scientifically revealing the spatial heterogeneity and the relationship between the fragmentation of urban landscape and the direct carbon emissions are of great significance to land management and urban planning. In fact, the linear and nonlinear effects among the various factors resulted in the carbon emission spatial map. However, there is lack of the studies on the direct and indirect relations between the carbon emission and the city functional spatial form changes, which could not be reflected by the land use change. The linear strength and direction of the single factor could be calculated through the correlation and Geographically Weighted Regression (GWR) analysis, the nonlinear power of one factor and the interaction power of each two factors could be quantified by the Geodetector analysis. Therefore, we compared the landscape fragmentation metrics of the urban land cover and functional district patches to characterize the landscape form and then revealed the relations between the landscape fragmentation level and the direct the carbon emissions based on the three methods. The results showed that fragmentation decreased and the fragmented patches clustered at the coarser resolution. The direct CO2 emission density and the population density increased when the fragmentation level aggregated. The correlation analysis indicated the weak linear relation between them. The spatial variation of GWR output indicated the fragmentation indicator (MESH) had the positive influence on the carbon emission located in the relatively high emission region, and the negative effects regions accounted for the small part of the area. The Geodetector which explores the nonlinear relation identified the DIVISION and MESH as the most powerful direct factor for the land cover patches, NP and PD for the functional district patches, and the interactions between fragmentation indicator (MESH) and urban sprawl metrics (PUA and DIS) had the greatly increased explanation powers on the urban carbon emission. Overall, this study provides a framework to understand the relation between the urban landscape fragmentation and the carbon emission for the low carbon city construction planning in the other cities.
Parametric dependence of ion temperature and relative density in the NASA Lewis SUMMA facility. [superconducting magnetic mirror

NASA Technical Reports Server (NTRS)

Snyder, A.; Lauver, M. R.; Patch, R. W.

1976-01-01

Further hot-ion plasma experiments were conducted in the SUMMA superconducting magnetic mirror facility. A steady-state ExB plasma was formed by applying a strong radially inward dc electric field between cylindrical anodes and hollow cathodes located near the magnetic mirror maxima. Extending the use of water cooling to the hollow cathodes, in addition to the anodes, resulted in higher maximum power input to the plasma. Steady-state hydrogen plasmas with ion kinetic temperatures as high as 830 eV were produced. Functional relations were obtained empirically among the plasma current, voltage, magnetic flux density, ion temperature, and relative ion density. The functional relations were deduced by use of a multiple correlation analysis. Data were obtained for midplane magnetic fields from 0.5 to 3.37 tesla and input power up to 45 kW. Also, initial absolute electron density measurements are reported from a 90 deg Thomson scattering laser system.
Research and development of energy harvesting from vibrations and human motions (Conference Presentation)

NASA Astrophysics Data System (ADS)

Liao, Wei-Hsin

2017-04-01

Most of the ambient energy, which was regarded useless in the past, now is under the spotlight. With the rapid developments on low power electronics, future personal mobile devices and remote sensing systems might become self-powered by scavenging energy in different forms from their surroundings. Kinetic energy is one of the promising energy forms in our living environment, e.g., human motions and vibrations. We have proposed an energy flow to clarify the functions of piezoelectric energy harvesting, dissipation, and their effects on the structural damping of vibrating structures. Impedance modeling and analysis were performed. We have designed an improved self-powered switching interface for piezoelectric energy harvesting circuits. With electromagnetic transduction, we also proposed a knee-mounted energy harvester that could convert the mechanical power from knee joints into electricity during walking. On the other hand, we have developed magnetorheological (MR) fluid devices with multiple functions, including rotary actuators and linear dampers. Multifunctional rotary actuator was designed to integrate motor/generator part and MR fluids into a single device. The actuator could function as motor, generator, clutch and brake, with compact size and good energy efficiency. In addition, novel self-sensing MR dampers with power generation, so as to integrate the dynamic sensing, controllable damping and power generation functions, were developed and investigated. Prototypes were fabricated and tested. The developed actuators were promising for various applications. In this paper, related research in energy harvesting done at The Chinese University of Hong Kong and key results will be presented.
Preliminary Chaotic Model of Snapover on High Voltage Solar Cells

NASA Technical Reports Server (NTRS)

Mackey, Willie R.

1995-01-01

High voltage power systems in space will interact with the space plasma in a variety of ways. One of these, Snapover, is characterized by a sudden enlargement of the electron current collection area across normally insulating surfaces. A power drain on solar array power systems will results from this enhanced current collection. Optical observations of the snapover phenomena in the laboratory indicates a functional relation between bia potential and surface glow area. This paper shall explore the potential benefits of modeling the relation between current and bia potential as an aspect of bifurcation analysis in chaos theory. Successful characterizations of snapover as a chaotic phenomena may provide a means of snapover prevention and control through chaotic synchronization.
77 FR 27113 - Export and Import of Nuclear Equipment and Material; Export of International Atomic Energy Agency...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-09

... relations, Nuclear materials, Nuclear power plants and reactors, Reporting and recordkeeping requirements... Reorganization Act sec. 201 (42 U.S.C. 5841; Solar, Wind, Waste, and Geothermal Power Act of 1990 sec. 5 (42 U.S... security of the United States. Because this rule involves a foreign affairs function of the United States...
Chemical Inventory Management at NASA Lewis Research Center

NASA Technical Reports Server (NTRS)

Kraft, Shirley S.; Homan, Joseph R.; Bajorek, Michael J.; Dominguez, Manuel B.; Smith, Vanessa L.

1997-01-01

The Chemical Management System (CMS) is a client/server application developed with Power Builder and Sybase for the Lewis Research Center (LeRC). Power Builder is a client-server application development tool, Sybase is a Relational Database Management System. The entire LeRC community can access the CMS from any desktop environment. The multiple functions and benefits of the CMS are addressed.

"Cloud" functions and templates of engineering calculations for nuclear power plants

NASA Astrophysics Data System (ADS)

Ochkov, V. F.; Orlov, K. A.; Ko, Chzho Ko

2014-10-01

The article deals with an important problem of setting up computer-aided design calculations of various circuit configurations and power equipment carried out using the templates and standard computer programs available in the Internet. Information about the developed Internet-based technology for carrying out such calculations using the templates accessible in the Mathcad Prime software package is given. The technology is considered taking as an example the solution of two problems relating to the field of nuclear power engineering.
Relationship of quadriceps muscle power and optimal shortening velocity with angiotensin-converting enzyme activity in older women.

PubMed

Kostka, Joanna; Sikora, Joanna; Kostka, Tomasz

2017-01-01

The goal of this study was to assess whether angiotensin-converting enzyme (ACE) activity is related to muscle function (strength, power and velocity), as well as to assess if ACE inhibitors (ACEIs) and other angiotensin system blocking medications (ASBMs) influence muscle performance in elderly women. Ninety-five community-dwelling elderly women took part in this study. Anthropometric data, blood ACE activity analysis, maximum power (P max ) and optimal shortening velocity (υ opt ) of the knee extensor muscles, handgrip strength, physical activity (PA) and functional performance were measured. Women taking ACEI were on average almost 2 years older than the women who did not take ACEI. They took more medicines and were also characterized by significantly lower level of ACE, but they did not differ in terms of PA level, results of functional performance and parameters characterizing muscle functions. No correlations of ACE activity with P max and handgrip strength, as well as with PA or functional performance were found. Higher ACE activity was connected with lower υ opt for women who did not take any ASBMs (rho =-0.37; p =0.01). Serum ACE activity was not associated with muscle strength, power and functional performance in both ASBM users and nonusers, but was associated with optimal shortening velocity of quadriceps muscles in older women. Further prospective studies are needed to assess if ACEIs or other ASBMs may slow down the decline in muscle function and performance.
An empirical comparison of SPM preprocessing parameters to the analysis of fMRI data.

PubMed

Della-Maggiore, Valeria; Chau, Wilkin; Peres-Neto, Pedro R; McIntosh, Anthony R

2002-09-01

We present the results from two sets of Monte Carlo simulations aimed at evaluating the robustness of some preprocessing parameters of SPM99 for the analysis of functional magnetic resonance imaging (fMRI). Statistical robustness was estimated by implementing parametric and nonparametric simulation approaches based on the images obtained from an event-related fMRI experiment. Simulated datasets were tested for combinations of the following parameters: basis function, global scaling, low-pass filter, high-pass filter and autoregressive modeling of serial autocorrelation. Based on single-subject SPM analysis, we derived the following conclusions that may serve as a guide for initial analysis of fMRI data using SPM99: (1) The canonical hemodynamic response function is a more reliable basis function to model the fMRI time series than HRF with time derivative. (2) Global scaling should be avoided since it may significantly decrease the power depending on the experimental design. (3) The use of a high-pass filter may be beneficial for event-related designs with fixed interstimulus intervals. (4) When dealing with fMRI time series with short interstimulus intervals (<8 s), the use of first-order autoregressive model is recommended over a low-pass filter (HRF) because it reduces the risk of inferential bias while providing a relatively good power. For datasets with interstimulus intervals longer than 8 seconds, temporal smoothing is not recommended since it decreases power. While the generalizability of our results may be limited, the methods we employed can be easily implemented by other scientists to determine the best parameter combination to analyze their data.
On the Spike Train Variability Characterized by Variance-to-Mean Power Relationship.

PubMed

Koyama, Shinsuke

2015-07-01

We propose a statistical method for modeling the non-Poisson variability of spike trains observed in a wide range of brain regions. Central to our approach is the assumption that the variance and the mean of interspike intervals are related by a power function characterized by two parameters: the scale factor and exponent. It is shown that this single assumption allows the variability of spike trains to have an arbitrary scale and various dependencies on the firing rate in the spike count statistics, as well as in the interval statistics, depending on the two parameters of the power function. We also propose a statistical model for spike trains that exhibits the variance-to-mean power relationship. Based on this, a maximum likelihood method is developed for inferring the parameters from rate-modulated spike trains. The proposed method is illustrated on simulated and experimental spike trains.
Improved GART neural network model for pattern classification and rule extraction with application to power systems.

PubMed

Yap, Keem Siah; Lim, Chee Peng; Au, Mau Teng

2011-12-01

Generalized adaptive resonance theory (GART) is a neural network model that is capable of online learning and is effective in tackling pattern classification tasks. In this paper, we propose an improved GART model (IGART), and demonstrate its applicability to power systems. IGART enhances the dynamics of GART in several aspects, which include the use of the Laplacian likelihood function, a new vigilance function, a new match-tracking mechanism, an ordering algorithm for determining the sequence of training data, and a rule extraction capability to elicit if-then rules from the network. To assess the effectiveness of IGART and to compare its performances with those from other methods, three datasets that are related to power systems are employed. The experimental results demonstrate the usefulness of IGART with the rule extraction capability in undertaking classification problems in power systems engineering.
Body-mass dependence of age-related deterioration in human muscular function.

PubMed

Meltzer, D E

1996-04-01

Maximal anaerobic power of human muscles declines with increasing chronological age and is correlated with body mass. This study investigated whether the rate of deterioration in human muscular function among trained weight lifters is also correlated with body mass. Cross-sectional analysis of performance data of over 1,100 Masters competitors in Olympic-style weight lifting was carried out; eight body-weight classes and six age groups were represented. Two-lift total data (sum of snatch and clean and jerk lifts) were analyzed. Mean deterioration rates in the performance of athletes of widely diverse body masses were compared over the following age ranges: 42-57, 42-62, and 42-67 yr. No statistically significant correlation (P < 0.05) was found between rate of performance decline and body mass. The relationship between body mass and the magnitude of age-related variation of deterioration rate was also studied; no significant correlation was found. Previous studies have demonstrated that performance in Olympic-style weight lifting is correlated with maximal anaerobic muscular power. This leads us to suggest that the age-related deterioration rate of anaerobic power in trained subjects may not be correlated with the body mass of the individual.
Characterization of rainbow trout (Oncorhynchus mykiss) spleen transcriptome and identification of immune-related genes

USDA-ARS?s Scientific Manuscript database

Resistance against specific diseases is affecting profitability in fish production systems including rainbow trout. Limited information is known about functions and mechanisms of the immune gene pathways in teleosts. Immunogenomics are powerful tools to determine immune-related genes/gene pathways a...
Performance of bed load transport equations in mountain gravel-bed rivers: A re-analysis

Treesearch

Jeffrey J. Barry; John M. Buffington; John G. King; Peter Goodwin

2006-01-01

Our recent examination of bed load transport data from mountain gravel-bed rivers in the western United States shows that the data can be fit by a simple power function of discharge, with the coefficient being a function of drainage area (a surrogate for basin sediment supply) and the exponent being a function of supply-related channel armoring (transport capacity in...
Cortical thickness as a contributor to abnormal oscillations in schizophrenia?

PubMed

Edgar, J Christopher; Chen, Yu-Han; Lanza, Matthew; Howell, Breannan; Chow, Vivian Y; Heiken, Kory; Liu, Song; Wootton, Cassandra; Hunter, Michael A; Huang, Mingxiong; Miller, Gregory A; Cañive, José M

2014-01-01

Although brain rhythms depend on brain structure (e.g., gray and white matter), to our knowledge associations between brain oscillations and structure have not been investigated in healthy controls (HC) or in individuals with schizophrenia (SZ). Observing function-structure relationships, for example establishing an association between brain oscillations (defined in terms of amplitude or phase) and cortical gray matter, might inform models on the origins of psychosis. Given evidence of functional and structural abnormalities in primary/secondary auditory regions in SZ, the present study examined how superior temporal gyrus (STG) structure relates to auditory STG low-frequency and 40 Hz steady-state activity. Given changes in brain activity as a function of age, age-related associations in STG oscillatory activity were also examined. Thirty-nine individuals with SZ and 29 HC were recruited. 40 Hz amplitude-modulated tones of 1 s duration were presented. MEG and T1-weighted sMRI data were obtained. Using the sources localizing 40 Hz evoked steady-state activity (300 to 950 ms), left and right STG total power and inter-trial coherence were computed. Time-frequency group differences and associations with STG structure and age were also examined. Decreased total power and inter-trial coherence in SZ were observed in the left STG for initial post-stimulus low-frequency activity (~ 50 to 200 ms, ~ 4 to 16 Hz) as well as 40 Hz steady-state activity (~ 400 to 1000 ms). Left STG 40 Hz total power and inter-trial coherence were positively associated with left STG cortical thickness in HC, not in SZ. Left STG post-stimulus low-frequency and 40 Hz total power were positively associated with age, again only in controls. Left STG low-frequency and steady-state gamma abnormalities distinguish SZ and HC. Disease-associated damage to STG gray matter in schizophrenia may disrupt the age-related left STG gamma-band function-structure relationships observed in controls.
Pump dependence of the dynamics of quantum dot based waveguide absorbers

NASA Astrophysics Data System (ADS)

Viktorov, Evgeny A.; Erneux, Thomas; Piwonski, Tomasz; Pulka, Jaroslaw; Huyet, Guillaume; Houlihan, John

2012-06-01

The nonlinear two stage recovery of quantum dot based reverse-biased waveguide absorbers is investigated experimentally and analytically as a function of the initial ground state occupation probability of the dot. The latter is controlled experimentally by the pump pulse power. The slow stage of the recovery is exponential and its basic timescale is independent of pump power. The fast stage of the recovery is a logistic function which we analyze in detail. The relative strength of slow to fast components is highlighted and the importance of higher order absorption processes at the highest pump level is demonstrated.
On the effects of surrogacy of energy dissipation in determining the intermittency exponent in fully developed turbulence

NASA Astrophysics Data System (ADS)

Cleve, J.; Greiner, M.; Sreenivasan, K. R.

2003-03-01

The two-point correlation function of the energy dissipation, obtained from a one-point time record of an atmospheric boundary layer, reveals a rigorous power law scaling with intermittency exponent μ approx 0.20 over almost the entire inertial range of scales. However, for the related integral moment, the power law scaling is restricted to the upper part of the inertial range only. This observation is explained in terms of the operational surrogacy of the construction of energy dissipation, which influences the behaviour of the correlation function for small separation distances.
Call Me Alix, Not Elix: Vowels Are More Important than Consonants in Own-Name Recognition at 5 Months

ERIC Educational Resources Information Center

Bouchon, Camillia; Floccia, Caroline; Fux, Thibaut; Adda-Decker, Martine; Nazzi, Thierry

2015-01-01

Consonants and vowels differ acoustically and articulatorily, but also functionally: Consonants are more relevant for lexical processing, and vowels for prosodic/syntactic processing. These functional biases could be powerful bootstrapping mechanisms for learning language, but their developmental origin remains unclear. The relative importance of…
Novel Analog For Muscle Deconditioning

NASA Technical Reports Server (NTRS)

Ploutz-Snyder, Lori; Ryder, Jeff; Buxton, Roxanne; Redd. Elizabeth; Scott-Pandorf, Melissa; Hackney, Kyle; Fiedler, James; Ploutz-Snyder, Robert; Bloomberg, Jacob

2011-01-01

Existing models (such as bed rest) of muscle deconditioning are cumbersome and expensive. We propose a new model utilizing a weighted suit to manipulate strength, power, or endurance (function) relative to body weight (BW). Methods: 20 subjects performed 7 occupational astronaut tasks while wearing a suit weighted with 0-120% of BW. Models of the full relationship between muscle function/BW and task completion time were developed using fractional polynomial regression and verified by the addition of pre-and postflightastronaut performance data for the same tasks. Splineregression was used to identify muscle function thresholds below which task performance was impaired. Results: Thresholds of performance decline were identified for each task. Seated egress & walk (most difficult task) showed thresholds of leg press (LP) isometric peak force/BW of 18 N/kg, LP power/BW of 18 W/kg, LP work/BW of 79 J/kg, isokineticknee extension (KE)/BW of 6 Nm/kg, and KE torque/BW of 1.9 Nm/kg.Conclusions: Laboratory manipulation of relative strength has promise as an appropriate analog for spaceflight-induced loss of muscle function, for predicting occupational task performance and establishing operationally relevant strength thresholds.
The Role of Work-Related Learning in the Identity Transformation of Canadian Workers with Low Literacy Skills

ERIC Educational Resources Information Center

Taylor, Maurice C.; Trumpower, David L.; Purse, Edward R.

2015-01-01

Workplaces are settings where power, knowledge and self are brought together in a complex social environment which includes various forms of struggle related to identity, agency, socio-cultural norms, political structures and functional practices. The purpose of this article is to uncover how formal and informal work-related learning processes…
Competitiveness in the sawmills and wood preservation industry in the United States and Canada

Treesearch

Rao V Nagubadi; Daowei Zhang

2010-01-01

We examine relative prices, relative productivity levels, and competitiveness in the sawmills and wood preservation industry in the united states and Canada between 1958 and 2003 by using purchasing power parities and bilateral translog production function. Our results show that the competitiveness of the Canadian industy is facilitated by higher relative productivity...
Age, Sex, and Body Composition as Predictors of Children's Performance on Basic Motor Abilities and Health-Related Fitness Items.

ERIC Educational Resources Information Center

Pissanos, Becky W.; And Others

1983-01-01

Step-wise linear regressions were used to relate children's age, sex, and body composition to performance on basic motor abilities including balance, speed, agility, power, coordination, and reaction time, and to health-related fitness items including flexibility, muscle strength and endurance and cardiovascular functions. Eighty subjects were in…
Orphan and gene related CpG Islands follow power-law-like distributions in several genomes: evidence of function-related and taxonomy-related modes of distribution.

PubMed

Tsiagkas, Giannis; Nikolaou, Christoforos; Almirantis, Yannis

2014-12-01

CpG Islands (CGIs) are compositionally defined short genomic stretches, which have been studied in the human, mouse, chicken and later in several other genomes. Initially, they were assigned the role of transcriptional regulation of protein-coding genes, especially the house-keeping ones, while more recently there is found evidence that they are involved in several other functions as well, which might include regulation of the expression of RNA genes, DNA replication etc. Here, an investigation of their distributional characteristics in a variety of genomes is undertaken for both whole CGI populations as well as for CGI subsets that lie away from known genes (gene-unrelated or "orphan" CGIs). In both cases power-law-like linearity in double logarithmic scale is found. An evolutionary model, initially put forward for the explanation of a similar pattern found in gene populations is implemented. It includes segmental duplication events and eliminations of most of the duplicated CGIs, while a moderate rate of non-duplicated CGI eliminations is also applied in some cases. Simulations reproduce all the main features of the observed inter-CGI chromosomal size distributions. Our results on power-law-like linearity found in orphan CGI populations suggest that the observed distributional pattern is independent of the analogous pattern that protein coding segments were reported to follow. The power-law-like patterns in the genomic distributions of CGIs described herein are found to be compatible with several other features of the composition, abundance or functional role of CGIs reported in the current literature across several genomes, on the basis of the proposed evolutionary model. Copyright © 2014 Elsevier Ltd. All rights reserved.
Unified Sequence-Based Association Tests Allowing for Multiple Functional Annotations and Meta-analysis of Noncoding Variation in Metabochip Data.

PubMed

He, Zihuai; Xu, Bin; Lee, Seunggeun; Ionita-Laza, Iuliana

2017-09-07

Substantial progress has been made in the functional annotation of genetic variation in the human genome. Integrative analysis that incorporates such functional annotations into sequencing studies can aid the discovery of disease-associated genetic variants, especially those with unknown function and located outside protein-coding regions. Direct incorporation of one functional annotation as weight in existing dispersion and burden tests can suffer substantial loss of power when the functional annotation is not predictive of the risk status of a variant. Here, we have developed unified tests that can utilize multiple functional annotations simultaneously for integrative association analysis with efficient computational techniques. We show that the proposed tests significantly improve power when variant risk status can be predicted by functional annotations. Importantly, when functional annotations are not predictive of risk status, the proposed tests incur only minimal loss of power in relation to existing dispersion and burden tests, and under certain circumstances they can even have improved power by learning a weight that better approximates the underlying disease model in a data-adaptive manner. The tests can be constructed with summary statistics of existing dispersion and burden tests for sequencing data, therefore allowing meta-analysis of multiple studies without sharing individual-level data. We applied the proposed tests to a meta-analysis of noncoding rare variants in Metabochip data on 12,281 individuals from eight studies for lipid traits. By incorporating the Eigen functional score, we detected significant associations between noncoding rare variants in SLC22A3 and low-density lipoprotein and total cholesterol, associations that are missed by standard dispersion and burden tests. Copyright © 2017 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.
Relationship of Sit-to-Stand Lower-Body Power With Functional Fitness Measures Among Older Adults With and Without Sarcopenia.

PubMed

Glenn, Jordan M; Gray, Michelle; Binns, Ashley

When evaluating health in older adults, batteries of tests are typically utilized to assess functional fitness. Unfortunately, physician's visits are time-sensitive, and it may be important to develop faster methods to assess functional fitness that can be utilized in professional or clinical settings. Therefore, the purpose of this investigation was to examine the relationship of sit-to-stand (STS) power generated through the STS task with previously established measures of functional fitness, specifically strength, endurance, speed, agility, and flexibility in older adults with and without sarcopenia. This study consisted of 57 community-dwelling older adults (n = 16 males; n = 41 females). Functional fitness was assessed using the Short Physical Performance Battery (SPPB), Senior Fitness Test, handgrip, gait speed (habitual and maximal), balance, and STS power generated via the Tendo Weightlifting Analyzer. On the basis of data distribution, second-degree polynomial (quadratic) curvilinear models (lines of best fit) were applied for the relationships of 5-time STS time with average and peak power. Zero-order correlations were evaluated between STS power and all other functional fitness measures. Older adults with sarcopenia were also identified (n = 15), and relationships were reevaluated within this subset. STS power (average and peak) was significantly (P ≤ .01) correlated with physical performance measured via previously established assessments. For average power, this was observed during the senior fitness test (6-minute walk [r = 0.39], 8-ft up-and-go [r = -0.46], arm curl [r = 0.46], and chair stand [r = 0.55]), SPPB (5-time STS time [r = -0.63] and 8-ft walk [r = -0.32]), and other independent functional fitness measures (grip strength [r = 0.65] and maximal gait speed [r = -0.31]). Similar results were observed for peak power during the senior fitness test (6-minute walk [r = 0.39], 8-ft up-and-go [r = -0.46], arm curl [r = 0.45], chair stand [r = 0.52], and sit-and-reach [r = -0.27]), SPPB (5-time STS time [r = -0.60] and 8-ft walk [r = -0.33]), and other independent functional fitness measures (grip strength [r = 0.70] and maximal gait speed [r = -0.32]). Within the sarcopenic subset, for average and peak power, respectively, significant relationships were still retained for handgrip strength (r = 0.57 and r = 0.57), 6-minute walk (r = 0.55 and r = 0.61), chair stand (r = 0.76 and r = 0.81), and 5-time STS time (r = -0.76 and r = -0.80) tests. STS power generated via the STS task significantly relates to commonly administered functional fitness measures. These relationships also appear to exist when evaluating these relationships in older adults with sarcopenia. STS power may be utilized as an independent measure of functional fitness that is feasible to incorporate in clinical settings where time and space are often limiting factors.
EEG alpha power and creative ideation☆

PubMed Central

Fink, Andreas; Benedek, Mathias

2014-01-01

Neuroscientific studies revealed first insights into neural mechanisms underlying creativity, but existing findings are highly variegated and often inconsistent. Despite the disappointing picture on the neuroscience of creativity drawn in recent reviews, there appears to be robust evidence that EEG alpha power is particularly sensitive to various creativity-related demands involved in creative ideation. Alpha power varies as a function of creativity-related task demands and the originality of ideas, is positively related to an individuals’ creativity level, and has been observed to increase as a result of creativity interventions. Alpha increases during creative ideation could reflect more internally oriented attention that is characterized by the absence of external bottom-up stimulation and, thus, a form of top-down activity. Moreover, they could indicate the involvement of specific memory processes such as the efficient (re-)combination of unrelated semantic information. We conclude that increased alpha power during creative ideation is among the most consistent findings in neuroscientific research on creativity and discuss possible future directions to better understand the manifold brain mechanisms involved in creativity. PMID:23246442

47 CFR 27.4 - Terms and definitions.

Code of Federal Regulations, 2014 CFR

2014-10-01

... product of the power supplied to the antenna and its gain relative to a half-wave dipole in a given... and the antenna gain in a given direction relative to an isotropic antenna. Fixed service. A radio... functions that could be performed at the transmitter. Satellite Digital Audio Radio Service (satellite DARS...
Statistical characteristics of dynamics for population migration driven by the economic interests

NASA Astrophysics Data System (ADS)

Huo, Jie; Wang, Xu-Ming; Zhao, Ning; Hao, Rui

2016-06-01

Population migration typically occurs under some constraints, which can deeply affect the structure of a society and some other related aspects. Therefore, it is critical to investigate the characteristics of population migration. Data from the China Statistical Yearbook indicate that the regional gross domestic product per capita relates to the population size via a linear or power-law relation. In addition, the distribution of population migration sizes or relative migration strength introduced here is dominated by a shifted power-law relation. To reveal the mechanism that creates the aforementioned distributions, a dynamic model is proposed based on the population migration rule that migration is facilitated by higher financial gains and abated by fewer employment opportunities at the destination, considering the migration cost as a function of the migration distance. The calculated results indicate that the distribution of the relative migration strength is governed by a shifted power-law relation, and that the distribution of migration distances is dominated by a truncated power-law relation. These results suggest the use of a power-law to fit a distribution may be not always suitable. Additionally, from the modeling framework, one can infer that it is the randomness and determinacy that jointly create the scaling characteristics of the distributions. The calculation also demonstrates that the network formed by active nodes, representing the immigration and emigration regions, usually evolves from an ordered state with a non-uniform structure to a disordered state with a uniform structure, which is evidenced by the increasing structural entropy.
Power Laws are Disguised Boltzmann Laws

NASA Astrophysics Data System (ADS)

Richmond, Peter; Solomon, Sorin

Using a previously introduced model on generalized Lotka-Volterra dynamics together with some recent results for the solution of generalized Langevin equations, we derive analytically the equilibrium mean field solution for the probability distribution of wealth and show that it has two characteristic regimes. For large values of wealth, it takes the form of a Pareto style power law. For small values of wealth, w<=wm, the distribution function tends sharply to zero. The origin of this law lies in the random multiplicative process built into the model. Whilst such results have been known since the time of Gibrat, the present framework allows for a stable power law in an arbitrary and irregular global dynamics, so long as the market is ``fair'', i.e., there is no net advantage to any particular group or individual. We further show that the dynamics of relative wealth is independent of the specific nature of the agent interactions and exhibits a universal character even though the total wealth may follow an arbitrary and complicated dynamics. In developing the theory, we draw parallels with conventional thermodynamics and derive for the system some new relations for the ``thermodynamics'' associated with the Generalized Lotka-Volterra type of stochastic dynamics. The power law that arises in the distribution function is identified with new additional logarithmic terms in the familiar Boltzmann distribution function for the system. These are a direct consequence of the multiplicative stochastic dynamics and are absent for the usual additive stochastic processes.
Hydrodynamics-based functional forms of activity metabolism: a case for the power-law polynomial function in animal swimming energetics.

PubMed

Papadopoulos, Anthony

2009-01-01

The first-degree power-law polynomial function is frequently used to describe activity metabolism for steady swimming animals. This function has been used in hydrodynamics-based metabolic studies to evaluate important parameters of energetic costs, such as the standard metabolic rate and the drag power indices. In theory, however, the power-law polynomial function of any degree greater than one can be used to describe activity metabolism for steady swimming animals. In fact, activity metabolism has been described by the conventional exponential function and the cubic polynomial function, although only the power-law polynomial function models drag power since it conforms to hydrodynamic laws. Consequently, the first-degree power-law polynomial function yields incorrect parameter values of energetic costs if activity metabolism is governed by the power-law polynomial function of any degree greater than one. This issue is important in bioenergetics because correct comparisons of energetic costs among different steady swimming animals cannot be made unless the degree of the power-law polynomial function derives from activity metabolism. In other words, a hydrodynamics-based functional form of activity metabolism is a power-law polynomial function of any degree greater than or equal to one. Therefore, the degree of the power-law polynomial function should be treated as a parameter, not as a constant. This new treatment not only conforms to hydrodynamic laws, but also ensures correct comparisons of energetic costs among different steady swimming animals. Furthermore, the exponential power-law function, which is a new hydrodynamics-based functional form of activity metabolism, is a special case of the power-law polynomial function. Hence, the link between the hydrodynamics of steady swimming and the exponential-based metabolic model is defined.
Statistical scaling of pore-scale Lagrangian velocities in natural porous media.

PubMed

Siena, M; Guadagnini, A; Riva, M; Bijeljic, B; Pereira Nunes, J P; Blunt, M J

2014-08-01

We investigate the scaling behavior of sample statistics of pore-scale Lagrangian velocities in two different rock samples, Bentheimer sandstone and Estaillades limestone. The samples are imaged using x-ray computer tomography with micron-scale resolution. The scaling analysis relies on the study of the way qth-order sample structure functions (statistical moments of order q of absolute increments) of Lagrangian velocities depend on separation distances, or lags, traveled along the mean flow direction. In the sandstone block, sample structure functions of all orders exhibit a power-law scaling within a clearly identifiable intermediate range of lags. Sample structure functions associated with the limestone block display two diverse power-law regimes, which we infer to be related to two overlapping spatially correlated structures. In both rocks and for all orders q, we observe linear relationships between logarithmic structure functions of successive orders at all lags (a phenomenon that is typically known as extended power scaling, or extended self-similarity). The scaling behavior of Lagrangian velocities is compared with the one exhibited by porosity and specific surface area, which constitute two key pore-scale geometric observables. The statistical scaling of the local velocity field reflects the behavior of these geometric observables, with the occurrence of power-law-scaling regimes within the same range of lags for sample structure functions of Lagrangian velocity, porosity, and specific surface area.
Determination of design and operation parameters for upper atmospheric research instrumentation to yield optimum resolution with deconvolution, appendix 2

NASA Technical Reports Server (NTRS)

Ioup, George E.; Ioup, Juliette W.

1988-01-01

This thesis reviews the technique established to clear channels in the Power Spectral Estimate by applying linear combinations of well known window functions to the autocorrelation function. The need for windowing the auto correlation function is due to the fact that the true auto correlation is not generally used to obtain the Power Spectral Estimate. When applied, the windows serve to reduce the effect that modifies the auto correlation by truncating the data and possibly the autocorrelation has on the Power Spectral Estimate. It has been shown in previous work that a single channel has been cleared, allowing for the detection of a small peak in the presence of a large peak in the Power Spectral Estimate. The utility of this method is dependent on the robustness of it on different input situations. We extend the analysis in this paper, to include clearing up to three channels. We examine the relative positions of the spikes to each other and also the effect of taking different percentages of lags of the auto correlation in the Power Spectral Estimate. This method could have application wherever the Power Spectrum is used. An example of this is beam forming for source location, where a small target can be located next to a large target. Other possibilities extend into seismic data processing. As the method becomes more automated other applications may present themselves.
What powers Hyperluminous infrared galaxies at z˜1-2?

NASA Astrophysics Data System (ADS)

Symeonidis, M.; Page, M. J.

2018-06-01

We investigate what powers hyperluminous infrared galaxies (HyLIRGs; LIR, 8-1000μm > 1013 L⊙) at z˜1-2, by examining the behaviour of the infrared AGN luminosity function in relation to the infrared galaxy luminosity function. The former corresponds to emission from AGN-heated dust only, whereas the latter includes emission from dust heated by stars and AGN. Our results show that the two luminosity functions are substantially different below 1013 L⊙ but converge in the HyLIRG regime. We find that the fraction of AGN dominated sources increases with total infrared luminosity and at L_IR>10^{13.5} L_{⊙} AGN can account for the entire infrared emission. We conclude that the bright end of the 1 < z < 2 infrared galaxy luminosity function is shaped by AGN rather than star-forming galaxies.
Independent from muscle power and balance performance, a creatinine clearance below 65 ml/min is a significant and independent risk factor for falls and fall-related fractures in elderly men and women diagnosed with osteoporosis.

PubMed

Dukas, L; Schacht, E; Runge, M

2010-07-01

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

PubMed

Kleinert, H; Zatloukal, V

2013-11-01

The statistics of rare events, the so-called black-swan events, is governed by non-Gaussian distributions with heavy power-like tails. We calculate the Green functions of the associated Fokker-Planck equations and solve the related stochastic differential equations. We also discuss the subject in the framework of path integration.
Functional requirements for onboard management of space shuttle consumables, volume 1

NASA Technical Reports Server (NTRS)

Graf, P. J.; Herwig, H. A.; Neel, L. W.

1973-01-01

A study was conducted to determine the functional requirements for onboard management of space shuttle consumables. A generalized consumable management concept was developed for application to advanced spacecraft. The subsystems and related consumables selected for inclusion in the consumables management system are: (1) propulsion, (2) power generation, and (3) environmental and life support.
The Correlates of Healthy Family Functioning: The Role of Consensus and Conflict in the Practice of Family Therapy.

ERIC Educational Resources Information Center

Green, Robert G.; Kolevzon, Michael F.

1986-01-01

Explored the relative importance of individual, dyadic, and triadic measures of intrafamily functioning in predicting family health. Dyadic measures pertaining to marital quality and parent-child relationships were more powerful predictors than either individual measures of emotional maturity, anxiety, self-esteem or locus of control, or triadic…
Prediction of Cardiorespiratory Fitness by the Six-Minute Step Test and Its Association with Muscle Strength and Power in Sedentary Obese and Lean Young Women: A Cross-Sectional Study

PubMed Central

Bonjorno Junior, José Carlos; de Oliveira, Cláudio Ricardo; Luporini, Rafael Luís; Mendes, Renata Gonçalves; Zangrando, Katiany Thais Lopes; Trimer, Renata; Arena, Ross

2015-01-01

Impaired cardiorespiratory fitness (CRF) is a hallmark characteristic in obese and lean sedentary young women. Peak oxygen consumption (VO2peak) prediction from the six-minute step test (6MST) has not been established for sedentary females. It is recognized that lower-limb muscle strength and power play a key role during functional activities. The aim of this study was to investigate cardiorespiratory responses during the 6MST and CPX and to develop a predictive equation to estimate VO2peak in both lean and obese subjects. Additionally we aim to investigate how muscle function impacts functional performance. Lean (LN = 13) and obese (OB = 18) women, aged 20–45, underwent a CPX, two 6MSTs, and isokinetic and isometric knee extensor strength and power evaluations. Regression analysis assessed the ability to predict VO2peak from the 6MST, age and body mass index (BMI). CPX and 6MST main outcomes were compared between LN and OB and correlated with strength and power variables. CRF, functional capacity, and muscle strength and power were lower in the OB compared to LN (<0.05). During the 6MST, LN and OB reached ~90% of predicted maximal heart rate and ~80% of the VO2peak obtained during CPX. BMI, age and number of step cycles (NSC) explained 83% of the total variance in VO2peak. Moderate to strong correlations between VO2peak at CPX and VO2peak at 6MST (r = 0.86), VO2peak at CPX and NSC (r = 0.80), as well as between VO2peak, NSC and muscle strength and power variables were found (p<0.05). These findings indicate the 6MST, BMI and age accurately predict VO2peak in both lean and obese young sedentary women. Muscle strength and power were related to measures of aerobic and functional performance. PMID:26717568
Rolling scheduling of electric power system with wind power based on improved NNIA algorithm

NASA Astrophysics Data System (ADS)

Xu, Q. S.; Luo, C. J.; Yang, D. J.; Fan, Y. H.; Sang, Z. X.; Lei, H.

2017-11-01

This paper puts forth a rolling modification strategy for day-ahead scheduling of electric power system with wind power, which takes the operation cost increment of unit and curtailed wind power of power grid as double modification functions. Additionally, an improved Nondominated Neighbor Immune Algorithm (NNIA) is proposed for solution. The proposed rolling scheduling model has further improved the operation cost of system in the intra-day generation process, enhanced the system’s accommodation capacity of wind power, and modified the key transmission section power flow in a rolling manner to satisfy the security constraint of power grid. The improved NNIA algorithm has defined an antibody preference relation model based on equal incremental rate, regulation deviation constraints and maximum & minimum technical outputs of units. The model can noticeably guide the direction of antibody evolution, and significantly speed up the process of algorithm convergence to final solution, and enhance the local search capability.
Analysis of temporal transcription expression profiles reveal links between protein function and developmental stages of Drosophila melanogaster.

PubMed

Wan, Cen; Lees, Jonathan G; Minneci, Federico; Orengo, Christine A; Jones, David T

2017-10-01

Accurate gene or protein function prediction is a key challenge in the post-genome era. Most current methods perform well on molecular function prediction, but struggle to provide useful annotations relating to biological process functions due to the limited power of sequence-based features in that functional domain. In this work, we systematically evaluate the predictive power of temporal transcription expression profiles for protein function prediction in Drosophila melanogaster. Our results show significantly better performance on predicting protein function when transcription expression profile-based features are integrated with sequence-derived features, compared with the sequence-derived features alone. We also observe that the combination of expression-based and sequence-based features leads to further improvement of accuracy on predicting all three domains of gene function. Based on the optimal feature combinations, we then propose a novel multi-classifier-based function prediction method for Drosophila melanogaster proteins, FFPred-fly+. Interpreting our machine learning models also allows us to identify some of the underlying links between biological processes and developmental stages of Drosophila melanogaster.
Muscle power is an important measure to detect deficits in muscle function in hip osteoarthritis: a cross-sectional study.

PubMed

Bieler, Theresa; Magnusson, Stig Peter; Christensen, Helle Elisabeth; Kjaer, Michael; Beyer, Nina

2017-07-01

To investigate between-leg differences in hip and thigh muscle strength and leg extensor power in patients with unilateral hip osteoarthritis. Further, to compare between-leg differences in knee extensor strength and leg extensor power between patients and healthy peers. Seventy-two patients (60-87 years) with radiographic and symptomatic hip osteoarthritis not awaiting hip replacement and 35 healthy peers (63-82 years) were included. Hip and thigh muscle strength and leg extensor power were measured in patients and knee extensor strength and leg extensor power in healthy. The symptomatic extremity in patients was significantly (p < 0.05, paired t-test) weaker compared with the non-symptomatic extremity for five hip muscles (8-17%), knee extensors (11%) and leg extensor power (19%). Healthy older adults had asymmetry in knee extensor strength (6%, p < 0.05) comparable to that found in patients, but had no asymmetry in leg extensor power. Patients had generalized weakening of the affected lower extremity and numerically the largest asymmetry was evident for leg extensor power. In contrast, healthy peers had no asymmetry in leg extensor power. These results indicate that exercise interventions focusing on improving leg extensor power of the symptomatic lower extremity and reducing asymmetry may be beneficial for patients with hip osteoarthritis. Implications for Rehabilitation Even in patients with mild symptoms not awaiting hip replacement a generalized muscle weakening of the symptomatic lower extremity seems to be present. Between-leg differences in leg extensor power (force × velocity) appears to be relatively large (19%) in patients with unilateral hip osteoarthritis in contrast to healthy peers who show no asymmetry. Compared to muscle strength the relationship between functional performance and leg extensor power seems to be stronger, and more strongly related to power of the symptomatic lower extremity. Our results indicate that exercise interventions focusing on improving leg extensor power of the symptomatic lower extremity and reducing asymmetry may be beneficial for patients with mild symptoms not awaiting hip replacement.
Deficient Event-Related Theta Oscillations in Individuals at Risk for Alcoholism: A Study of Reward Processing and Impulsivity Features

PubMed Central

Kamarajan, Chella; Pandey, Ashwini K.; Chorlian, David B.; Manz, Niklas; Stimus, Arthur T.; Anokhin, Andrey P.; Bauer, Lance O.; Kuperman, Samuel; Kramer, John; Bucholz, Kathleen K.; Schuckit, Marc A.; Hesselbrock, Victor M.; Porjesz, Bernice

2015-01-01

Background Individuals at high risk to develop alcoholism often manifest neurocognitive deficits as well as increased impulsivity. Event-related oscillations (EROs) have been used to effectively measure brain (dys)function during cognitive tasks in individuals with alcoholism and related disorders and in those at risk to develop these disorders. The current study examines ERO theta power during reward processing as well as impulsivity in adolescent and young adult subjects at high risk for alcoholism. Methods EROs were recorded during a monetary gambling task (MGT) in 12–25 years old participants (N = 1821; males = 48%) from high risk alcoholic families (HR, N = 1534) and comparison low risk community families (LR, N = 287) from the Collaborative Study on the Genetics of Alcoholism (COGA). Impulsivity scores and prevalence of externalizing diagnoses were also compared between LR and HR groups. Results HR offspring showed lower theta power and decreased current source density (CSD) activity than LR offspring during loss and gain conditions. Younger males had higher theta power than younger females in both groups, while the older HR females showed more theta power than older HR males. Younger subjects showed higher theta power than older subjects in each comparison. Differences in topography (i.e., frontalization) between groups were also observed. Further, HR subjects across gender had higher impulsivity scores and increased prevalence of externalizing disorders compared to LR subjects. Conclusions As theta power during reward processing is found to be lower not only in alcoholics, but also in HR subjects, it is proposed that reduced reward-related theta power, in addition to impulsivity and externalizing features, may be related in a predisposition to develop alcoholism and related disorders. PMID:26580209
Movement-related beta oscillations show high intra-individual reliability.

PubMed

Espenhahn, Svenja; de Berker, Archy O; van Wijk, Bernadette C M; Rossiter, Holly E; Ward, Nick S

2017-02-15

Oscillatory activity in the beta frequency range (15-30Hz) recorded from human sensorimotor cortex is of increasing interest as a putative biomarker of motor system function and dysfunction. Despite its increasing use in basic and clinical research, surprisingly little is known about the test-retest reliability of spectral power and peak frequency measures of beta oscillatory signals from sensorimotor cortex. Establishing that these beta measures are stable over time in healthy populations is a necessary precursor to their use in the clinic. Here, we used scalp electroencephalography (EEG) to evaluate intra-individual reliability of beta-band oscillations over six sessions, focusing on changes in beta activity during movement (Movement-Related Beta Desynchronization, MRBD) and after movement termination (Post-Movement Beta Rebound, PMBR). Subjects performed visually-cued unimanual wrist flexion and extension. We assessed Intraclass Correlation Coefficients (ICC) and between-session correlations for spectral power and peak frequency measures of movement-related and resting beta activity. Movement-related and resting beta power from both sensorimotor cortices was highly reliable across sessions. Resting beta power yielded highest reliability (average ICC=0.903), followed by MRBD (average ICC=0.886) and PMBR (average ICC=0.663). Notably, peak frequency measures yielded lower ICC values compared to the assessment of spectral power, particularly for movement-related beta activity (ICC=0.386-0.402). Our data highlight that power measures of movement-related beta oscillations are highly reliable, while corresponding peak frequency measures show greater intra-individual variability across sessions. Importantly, our finding that beta power estimates show high intra-individual reliability over time serves to validate the notion that these measures reflect meaningful individual differences that can be utilised in basic research and clinical studies. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.
Deficient Event-Related Theta Oscillations in Individuals at Risk for Alcoholism: A Study of Reward Processing and Impulsivity Features.

PubMed

Kamarajan, Chella; Pandey, Ashwini K; Chorlian, David B; Manz, Niklas; Stimus, Arthur T; Anokhin, Andrey P; Bauer, Lance O; Kuperman, Samuel; Kramer, John; Bucholz, Kathleen K; Schuckit, Marc A; Hesselbrock, Victor M; Porjesz, Bernice

2015-01-01

Individuals at high risk to develop alcoholism often manifest neurocognitive deficits as well as increased impulsivity. Event-related oscillations (EROs) have been used to effectively measure brain (dys)function during cognitive tasks in individuals with alcoholism and related disorders and in those at risk to develop these disorders. The current study examines ERO theta power during reward processing as well as impulsivity in adolescent and young adult subjects at high risk for alcoholism. EROs were recorded during a monetary gambling task (MGT) in 12-25 years old participants (N = 1821; males = 48%) from high risk alcoholic families (HR, N = 1534) and comparison low risk community families (LR, N = 287) from the Collaborative Study on the Genetics of Alcoholism (COGA). Impulsivity scores and prevalence of externalizing diagnoses were also compared between LR and HR groups. HR offspring showed lower theta power and decreased current source density (CSD) activity than LR offspring during loss and gain conditions. Younger males had higher theta power than younger females in both groups, while the older HR females showed more theta power than older HR males. Younger subjects showed higher theta power than older subjects in each comparison. Differences in topography (i.e., frontalization) between groups were also observed. Further, HR subjects across gender had higher impulsivity scores and increased prevalence of externalizing disorders compared to LR subjects. As theta power during reward processing is found to be lower not only in alcoholics, but also in HR subjects, it is proposed that reduced reward-related theta power, in addition to impulsivity and externalizing features, may be related in a predisposition to develop alcoholism and related disorders.
On the theory of behavioral mechanics.

PubMed

Dzendolet, E

1999-12-01

The Theory of Behavioral Mechanics is the behavioral analogue of Newton's laws of motion, with the rate of responding in operant conditioning corresponding to physical velocity. In an earlier work, the basic relation between rate of responding and sessions under two FI schedules and over a range of commonly used session values had been shown to be a power function. Using that basic relation, functions for behavioral acceleration, mass, and momentum are derived here. Data from other laboratories also support the applicability of a power function to VI schedules. A particular numerical value is introduced here to be the standard reference value for the behavioral force under the VI-60-s schedule. This reference allows numerical values to be calculated for the behavioral mass and momentum of individual animals. A comparison of the numerical values of the momenta of two animals can be used to evaluate their relative resistances to change, e.g., to extinction, which is itself viewed as a continuously changing behavioral force being imposed on the animal. This overall numerical approach allows behavioral force-values to be assigned to various experimental conditions such as the evaluation of the behavioral force of a medication dosage.
Autonomic nervous function in patients with Meniere's disease evaluated by power spectral analysis of heart rate variability.

PubMed

Yamada, M; Mizuta, K; Ito, Y; Furuta, M; Sawai, S; Miyata, H

1999-10-01

A hypothesis has been advanced that the autonomic nervous dysfunction (AND) relates to the development of vertigo in Meniere's disease (MD). We also studied the causal relationship between AND and vertigo in MD. We evaluated autonomic nervous function in 17 patients with MD (five men and 12 women ranging in age from 16 to 70 years) by classifying them by their stages of attack and interval of vertigo and with power spectral analysis (PSA) of heart rate variability. Fourteen healthy volunteers were also tested as controls. At the interval stage, parasympathetic nervous hypofunction and significant depression of sympathetic response due to postural changes from the supine to the standing position were observed in many of those patients. At the attack stage, sympathetic nervous hypofunction was observed in some of the patients. These findings lead us to the conclusion that AND relates to vertigo in MD as a predisposing factor. However, the question of whether AND relates as a trigger or as a consequence of vertigo in MD has not been adequately solved in this study. We will make further studies on circadian variation of autonomic nervous function.

Dissecting the genetics of the human transcriptome identifies novel trait-related trans-eQTLs and corroborates the regulatory relevance of non-protein coding loci†

PubMed Central

Kirsten, Holger; Al-Hasani, Hoor; Holdt, Lesca; Gross, Arnd; Beutner, Frank; Krohn, Knut; Horn, Katrin; Ahnert, Peter; Burkhardt, Ralph; Reiche, Kristin; Hackermüller, Jörg; Löffler, Markus; Teupser, Daniel; Thiery, Joachim; Scholz, Markus

2015-01-01

Genetics of gene expression (eQTLs or expression QTLs) has proved an indispensable tool for understanding biological pathways and pathomechanisms of trait-associated SNPs. However, power of most genome-wide eQTL studies is still limited. We performed a large eQTL study in peripheral blood mononuclear cells of 2112 individuals increasing the power to detect trans-effects genome-wide. Going beyond univariate SNP-transcript associations, we analyse relations of eQTLs to biological pathways, polygenetic effects of expression regulation, trans-clusters and enrichment of co-localized functional elements. We found eQTLs for about 85% of analysed genes, and 18% of genes were trans-regulated. Local eSNPs were enriched up to a distance of 5 Mb to the transcript challenging typically implemented ranges of cis-regulations. Pathway enrichment within regulated genes of GWAS-related eSNPs supported functional relevance of identified eQTLs. We demonstrate that nearest genes of GWAS-SNPs might frequently be misleading functional candidates. We identified novel trans-clusters of potential functional relevance for GWAS-SNPs of several phenotypes including obesity-related traits, HDL-cholesterol levels and haematological phenotypes. We used chromatin immunoprecipitation data for demonstrating biological effects. Yet, we show for strongly heritable transcripts that still little trans-chromosomal heritability is explained by all identified trans-eSNPs; however, our data suggest that most cis-heritability of these transcripts seems explained. Dissection of co-localized functional elements indicated a prominent role of SNPs in loci of pseudogenes and non-coding RNAs for the regulation of coding genes. In summary, our study substantially increases the catalogue of human eQTLs and improves our understanding of the complex genetic regulation of gene expression, pathways and disease-related processes. PMID:26019233
Alpha power indexes task-related networks on large and small scales: A multimodal ECoG study in humans and a non-human primate.

PubMed

de Pesters, A; Coon, W G; Brunner, P; Gunduz, A; Ritaccio, A L; Brunet, N M; de Weerd, P; Roberts, M J; Oostenveld, R; Fries, P; Schalk, G

2016-07-01

Performing different tasks, such as generating motor movements or processing sensory input, requires the recruitment of specific networks of neuronal populations. Previous studies suggested that power variations in the alpha band (8-12Hz) may implement such recruitment of task-specific populations by increasing cortical excitability in task-related areas while inhibiting population-level cortical activity in task-unrelated areas (Klimesch et al., 2007; Jensen and Mazaheri, 2010). However, the precise temporal and spatial relationships between the modulatory function implemented by alpha oscillations and population-level cortical activity remained undefined. Furthermore, while several studies suggested that alpha power indexes task-related populations across large and spatially separated cortical areas, it was largely unclear whether alpha power also differentially indexes smaller networks of task-related neuronal populations. Here we addressed these questions by investigating the temporal and spatial relationships of electrocorticographic (ECoG) power modulations in the alpha band and in the broadband gamma range (70-170Hz, indexing population-level activity) during auditory and motor tasks in five human subjects and one macaque monkey. In line with previous research, our results confirm that broadband gamma power accurately tracks task-related behavior and that alpha power decreases in task-related areas. More importantly, they demonstrate that alpha power suppression lags population-level activity in auditory areas during the auditory task, but precedes it in motor areas during the motor task. This suppression of alpha power in task-related areas was accompanied by an increase in areas not related to the task. In addition, we show for the first time that these differential modulations of alpha power could be observed not only across widely distributed systems (e.g., motor vs. auditory system), but also within the auditory system. Specifically, alpha power was suppressed in the locations within the auditory system that most robustly responded to particular sound stimuli. Altogether, our results provide experimental evidence for a mechanism that preferentially recruits task-related neuronal populations by increasing cortical excitability in task-related cortical areas and decreasing cortical excitability in task-unrelated areas. This mechanism is implemented by variations in alpha power and is common to humans and the non-human primate under study. These results contribute to an increasingly refined understanding of the mechanisms underlying the selection of the specific neuronal populations required for task execution. Copyright © 2016 Elsevier Inc. All rights reserved.
Relative Power of Specific EEG Bands and Their Ratios during Neurofeedback Training in Children with Autism Spectrum Disorder

PubMed Central

Wang, Yao; Sokhadze, Estate M.; El-Baz, Ayman S.; Li, Xiaoli; Sears, Lonnie; Casanova, Manuel F.; Tasman, Allan

2016-01-01

Neurofeedback is a mode of treatment that is potentially useful for improving self-regulation skills in persons with autism spectrum disorder. We proposed that operant conditioning of EEG in neurofeedback mode can be accompanied by changes in the relative power of EEG bands. However, the details on the change of the relative power of EEG bands during neurofeedback training course in autism are not yet well explored. In this study, we analyzed the EEG recordings of children diagnosed with autism and enrolled in a prefrontal neurofeedback treatment course. The protocol used in this training was aimed at increasing the ability to focus attention, and the procedure represented the wide band EEG amplitude suppression training along with upregulation of the relative power of gamma activity. Quantitative EEG analysis was completed for each session of neurofeedback using wavelet transform to determine the relative power of gamma and theta/beta ratio, and further to detect the statistical changes within and between sessions. We found a linear decrease of theta/beta ratio and a liner increase of relative power of gamma activity over 18 weekly sessions of neurofeedback in 18 high functioning children with autism. The study indicates that neurofeedback is an effective method for altering EEG characteristics associated with the autism spectrum disorder. Also, it provides information about specific changes of EEG activities and details the correlation between changes of EEG and neurofeedback indexes during the course of neurofeedback. This pilot study contributes to the development of more effective approaches to EEG data analysis during prefrontal neurofeedback training in autism. PMID:26834615
An Empirical Examination of Counterdrug Interdiction Program Effectiveness.

DTIC Science & Technology

1997-01-01

inversely correlated with the street price index. Chapter IV examines the time dependence of the street price index and argues that interdiction activities...essentially asymptotic behavior in which the cumulative distribution function, for large values of the independent variable, converges to an inverse power-law...log(S) /log(M). Such an inverse power-law relation between unit purchase price and purchase volume is indeed observed within the STRIDE data
The possible consequences for cognitive functions of external electric fields at power line frequency on hippocampal CA1 pyramidal neurons.

PubMed

Migliore, Rosanna; De Simone, Giada; Leinekugel, Xavier; Migliore, Michele

2017-04-01

The possible effects on cognitive processes of external electric fields, such as those generated by power line pillars and household appliances are of increasing public concern. They are difficult to study experimentally, and the relatively scarce and contradictory evidence make it difficult to clearly assess these effects. In this study, we investigate how, why and to what extent external perturbations of the intrinsic neuronal activity, such as those that can be caused by generation, transmission and use of electrical energy can affect neuronal activity during cognitive processes. For this purpose, we used a morphologically and biophysically realistic three-dimensional model of CA1 pyramidal neurons. The simulation findings suggest that an electric field oscillating at power lines frequency, and environmentally measured strength, can significantly alter both the average firing rate and temporal spike distribution properties of a hippocampal CA1 pyramidal neuron. This effect strongly depends on the specific and instantaneous relative spatial location of the neuron with respect to the field, and on the synaptic input properties. The model makes experimentally testable predictions on the possible functional consequences for normal hippocampal functions such as object recognition and spatial navigation. The results suggest that, although EF effects on cognitive processes may be difficult to occur in everyday life, their functional consequences deserve some consideration, especially when they constitute a systematic presence in living environments. © 2016 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.
All particle energy spectrum of cosmic rays in 10 to the 15th power - 10 to the 20th power eV region

NASA Technical Reports Server (NTRS)

Krasilnikov, D. D.; Dyakonov, M. N.; Ivanov, A. A.; Kolosov, V. A.; Lischenyuk, F. F.; Sleptsov, I. Y.

1985-01-01

Average estimations of the shower energy components are presented and their sum gives E sub 0 (Rho sub 600) - an average function of the relation of E sub 0 with the shower size parameter Rho sub 600 measured at the Yakutsk extensive air showers (EAS) array. Using this relation to the EAS spectrum obtained at the Akeno and Yakutsk arrays the energy spectrum of the cosmic ray total flux within 15 lg (E sub 0,eV) 20 by the EAS methods is recovered.
Single-trial EEG-informed fMRI analysis of emotional decision problems in hot executive function.

PubMed

Guo, Qian; Zhou, Tiantong; Li, Wenjie; Dong, Li; Wang, Suhong; Zou, Ling

2017-07-01

Executive function refers to conscious control in psychological process which relates to thinking and action. Emotional decision is a part of hot executive function and contains emotion and logic elements. As a kind of important social adaptation ability, more and more attention has been paid in recent years. Gambling task can be well performed in the study of emotional decision. As fMRI researches focused on gambling task show not completely consistent brain activation regions, this study adopted EEG-fMRI fusion technology to reveal brain neural activity related with feedback stimuli. In this study, an EEG-informed fMRI analysis was applied to process simultaneous EEG-fMRI data. First, relative power-spectrum analysis and K-means clustering method were performed separately to extract EEG-fMRI features. Then, Generalized linear models were structured using fMRI data and using different EEG features as regressors. The results showed that in the win versus loss stimuli, the activated regions almost covered the caudate, the ventral striatum (VS), the orbital frontal cortex (OFC), and the cingulate. Wide activation areas associated with reward and punishment were revealed by the EEG-fMRI integration analysis than the conventional fMRI results, such as the posterior cingulate and the OFC. The VS and the medial prefrontal cortex (mPFC) were found when EEG power features were performed as regressors of GLM compared with results entering the amplitudes of feedback-related negativity (FRN) as regressors. Furthermore, the brain region activation intensity was the strongest when theta-band power was used as a regressor compared with the other two fusion results. The EEG-based fMRI analysis can more accurately depict the whole-brain activation map and analyze emotional decision problems.
The Cybathlon promotes the development of assistive technology for people with physical disabilities.

PubMed

Riener, Robert

2016-05-31

The Cybathlon is a new kind of championship, where people with physical disabilities compete against each other at tasks of daily life, with the aid of advanced assistive devices including robotic technologies. The first championship will take place at the Swiss Arena Kloten, Zurich, on 8 October 2016. Six disciplines are part of the competition comprising races with powered leg prostheses, powered arm prostheses, functional electrical stimulation driven bikes, powered wheelchairs, powered exoskeletons and brain-computer interfaces. This commentary describes the six disciplines and explains the current technological deficiencies that have to be addressed by the competing teams. These deficiencies at present often lead to disappointment or even rejection of some of the related technologies in daily applications. The Cybathlon aims to promote the development of useful technologies that facilitate the lives of people with disabilities. In the long run, the developed devices should become affordable and functional for all relevant activities in daily life.
Reliability and relationships among handgrip strength, leg extensor strength and power, and balance in older men.

PubMed

Jenkins, Nathaniel D M; Buckner, Samuel L; Bergstrom, Haley C; Cochrane, Kristen C; Goldsmith, Jacob A; Housh, Terry J; Johnson, Glen O; Schmidt, Richard J; Cramer, Joel T

2014-10-01

To quantify the reliability of isometric leg extension torque (LEMVC), rate of torque development (LERTD), isometric handgrip force (HGMVC) and RFD (HGRFD), isokinetic leg extension torque and power at 1.05rad·s(-1) and 3.14rad·s(-1); and explore relationships among strength, power, and balance in older men. Sixteen older men completed 3 isometric handgrips, 3 isometric leg extensions, and 3 isokinetic leg extensions at 1.05rad·s(-1) and 3.14rad·s(-1) during two visits. Intraclass correlation coefficients (ICCs), ICC confidence intervals (95% CI), coefficients of variation (CVs), and Pearson correlation coefficients were calculated. LERTD demonstrated no reliability. The CVs for LERTD and HGRFD were ≤23.26%. HGMVC wasn't related to leg extension torque or power, or balance (r=0.14-0.47; p>0.05). However, moderate to strong relationships were found among isokinetic leg extension torque at 1.05rad·s(-1) and 3.14rad·s(-1), leg extension mean power at 1.05rad·s(-1), and functional reach (r=0.51-0.95; p≤0.05). LERTD and HGRFD weren't reliable and shouldn't be used as outcome variables in older men. Handgrip strength may not be an appropriate surrogate for lower body strength, power, or balance. Instead, perhaps handgrip strength should only be used to describe upper body strength or functionality, which may compliment isokinetic assessments of lower body strength, which were reliable and related to balance. Copyright © 2014 Elsevier Inc. All rights reserved.
Systematic review of power mobility outcomes for infants, children and adolescents with mobility limitations.

PubMed

Livingstone, Roslyn; Field, Debra

2014-10-01

To summarize and critically appraise the evidence related to power mobility use in children (18 years or younger) with mobility limitations. Searches were performed in 12 electronic databases along with hand searching for articles published in English to September 2012 and updated February 2014. The search was restricted to quantitative studies including at least one child with a mobility limitation and measuring an outcome related to power mobility device use. Articles were appraised using American Academy of Cerebral Palsy and Developmental Medicine (AACPDM) criteria for group and single-subject designs. The PRISMA statement was followed with inclusion criteria set a priori. Two reviewers independently screened titles, abstracts and full-text articles. AACPDM quality ratings were completed for levels I-III studies. Of 259 titles, 29 articles met inclusion criteria, describing 28 primary research studies. One study, rated as strong level II evidence, supported positive impact of power mobility on overall development as well as independent mobility. Another study, rated as moderate level III evidence, supported positive impact on self-initiated movement. Remaining studies, rated evidence levels IV and V, provided support for a positive impact on a broad range of outcomes from to International Classification of Functioning (ICF) components of body structure and function, activity and participation. Some studies suggest that environmental factors may be influential in successful power mobility use and skill development. The body of evidence supporting outcomes for children using power mobility is primarily descriptive rather than experimental in nature, suggesting research in this area is in its infancy. © The Author(s) 2014.
Attributes and National Behavior, Part 2: Modern International Relations Monograph Series. Patterns of Conflict: Relative Status-Field Theory, TT Actors.

ERIC Educational Resources Information Center

Vincent, Jack E.

This monograph presents the computer printout of an analysis of data on international conflict over a three-year period. Part of a large scale research project to test various theories with regard to their power in analyzing international relations, this monograph presents data on the application of discriminant function analysis to 'topdog'…
Attributes and National Behavior, Part 2: Modern International Relations Monograph Series. Patterns of Conflict: Relative Status-Field Theory, TU Actors.

ERIC Educational Resources Information Center

Vincent, Jack E.

This monograph presents the computer printout of an analysis of data on international conflict over a three-year period. Part of a large scale research project to test various theories with regard to their power in analyzing international relations, this monograph presents data on the application of discriminant function analysis to combined…
Attributes and National Behavior, Part 2: Modern International Relations Monograph Series. Patterns of Cooperation: Relative Status-Field Theory, UT Actors.

ERIC Educational Resources Information Center

Vincent, Jack E.

This monograph presents the computer printout of an analysis of data on international cooperation over a three-year period. Part of a large scale research project to test various theories with regard to their power in analyzing international relations, this monograph presents data on the application of discriminant function analysis of combined…
Attributes and National Behavior, Part 2: Modern International Relations Monograph Series. Patterns of Conflict: Relative Status-Field Theory, UU Actors.

ERIC Educational Resources Information Center

Vincent, Jack E.

This monograph presents the computer printout of an analysis of data on international conflict over a three-year period. Part of a large scale research project to test various theories with regard to their power in analyzing international relations, this monograph presents data on the application of discriminant function analysis of 'underdog'…
Attributes and National Behavior, Part 2: Modern International Relations Monograph Series. Patterns of Cooperation: Relative Status-Field Theory, TU Actors.

ERIC Educational Resources Information Center

Vincent, Jack E.

This monograph presents the computer printout of an analysis of data on international cooperation over a three-year period. Part of a large scale research project to test various theories with regard to their power in analyzing international relations, this monograph presents data on the application of discriminant function analysis to combined…
Functional connectivity decreases in autism in emotion, self, and face circuits identified by Knowledge-based Enrichment Analysis.

PubMed

Cheng, Wei; Rolls, Edmund T; Zhang, Jie; Sheng, Wenbo; Ma, Liang; Wan, Lin; Luo, Qiang; Feng, Jianfeng

2017-03-01

A powerful new method is described called Knowledge based functional connectivity Enrichment Analysis (KEA) for interpreting resting state functional connectivity, using circuits that are functionally identified using search terms with the Neurosynth database. The method derives its power by focusing on neural circuits, sets of brain regions that share a common biological function, instead of trying to interpret single functional connectivity links. This provides a novel way of investigating how task- or function-related networks have resting state functional connectivity differences in different psychiatric states, provides a new way to bridge the gap between task and resting-state functional networks, and potentially helps to identify brain networks that might be treated. The method was applied to interpreting functional connectivity differences in autism. Functional connectivity decreases at the network circuit level in 394 patients with autism compared with 473 controls were found in networks involving the orbitofrontal cortex, anterior cingulate cortex, middle temporal gyrus cortex, and the precuneus, in networks that are implicated in the sense of self, face processing, and theory of mind. The decreases were correlated with symptom severity. Copyright © 2017. Published by Elsevier Inc.
Barium-Dispenser Thermionic Cathode

NASA Technical Reports Server (NTRS)

Wintucky, Edwin G.; Green, M.; Feinleib, M.

1989-01-01

Improved reservoir cathode serves as intense source of electrons required for high-frequency and often high-output-power, linear-beam tubes, for which long operating lifetime important consideration. High emission-current densities obtained through use of emitting surface of relatively-low effective work function and narrow work-function distribution, consisting of coat of W/Os deposited by sputtering. Lower operating temperatures and enhanced electron emission consequently possible.
7 CFR 2003.22 - Functional organization of RUS.

Code of Federal Regulations, 2010 CFR

2010-01-01

... engineering practices and specifications. (ii) Power Supply Division. Headed by a division director, this... office develops engineering practices, policies, and technical data related to borrowers' telecommunications systems; and evaluates the application of new communications network technology, including...
7 CFR 2003.22 - Functional organization of RUS.

Code of Federal Regulations, 2014 CFR

2014-01-01

... engineering practices and specifications. (ii) Power Supply Division. Headed by a division director, this... office develops engineering practices, policies, and technical data related to borrowers' telecommunications systems; and evaluates the application of new communications network technology, including...
7 CFR 2003.22 - Functional organization of RUS.

Code of Federal Regulations, 2011 CFR

2011-01-01

... engineering practices and specifications. (ii) Power Supply Division. Headed by a division director, this... office develops engineering practices, policies, and technical data related to borrowers' telecommunications systems; and evaluates the application of new communications network technology, including...

7 CFR 2003.22 - Functional organization of RUS.

Code of Federal Regulations, 2013 CFR

2013-01-01

... engineering practices and specifications. (ii) Power Supply Division. Headed by a division director, this... office develops engineering practices, policies, and technical data related to borrowers' telecommunications systems; and evaluates the application of new communications network technology, including...
7 CFR 2003.22 - Functional organization of RUS.

Code of Federal Regulations, 2012 CFR

2012-01-01

... engineering practices and specifications. (ii) Power Supply Division. Headed by a division director, this... office develops engineering practices, policies, and technical data related to borrowers' telecommunications systems; and evaluates the application of new communications network technology, including...
Experimental verification of ion stopping power prediction from dual energy CT data in tissue surrogates

NASA Astrophysics Data System (ADS)

Farace, Paolo

2014-11-01

A two-steps procedure is presented to convert dual-energy CT data to stopping power ratio (SPR), relative to water. In the first step the relative electron density (RED) is calculated from dual-energy CT-numbers by means of a bi-linear relationship: RED = a HUscH + b HUscL + c, where HUscH and HUscL are scaled units (HUsc = HU + 1000) acquired at high and low energy respectively, and the three parameters a, b and c has to be determined for each CT scanner. In the second step the RED values were converted into SPR by means of published poly-line functions, which are invariant as they do not depend on a specific CT scanner. The comparison with other methods provides encouraging results, with residual SPR error on human tissue within 1%. The distinctive features of the proposed method are its simplicity and the generality of the conversion functions.
Neutron stars: history of the magnetic field decay

NASA Astrophysics Data System (ADS)

Igoshev, Andrei P.; Kholtygin, Alexander F.

2013-03-01

Using the data of the ATNF pulsar catalog we study the relation connected the real age t of young neutron stars (NS) and their spin-down age τ. We suppose that this relation is independent from both initial period of the NS and its initial surface magnetic field, and that the laws of the surface magnetic field decay are similar for all NSs in the Milky Way. We further assume that the birth-rate of pulsars was constant during at least last 200 million years. With these assumptions we were able to restore the history of the magnetic field decay for the galactic NSs. We reconstruct the universal function f(t) = B(t)/B 0, where B 0 is the initial magnetic field and B(t) is the magnetic field of NS at the age t. The function f(t) can be fitted by a power law with power index α = -1.17.
Experimental verification of ion stopping power prediction from dual energy CT data in tissue surrogates.

PubMed

Farace, Paolo

2014-11-21

A two-steps procedure is presented to convert dual-energy CT data to stopping power ratio (SPR), relative to water. In the first step the relative electron density (RED) is calculated from dual-energy CT-numbers by means of a bi-linear relationship: RED=a HUscH+b HUscL+c, where HUscH and HUscL are scaled units (HUsc=HU+1000) acquired at high and low energy respectively, and the three parameters a, b and c has to be determined for each CT scanner. In the second step the RED values were converted into SPR by means of published poly-line functions, which are invariant as they do not depend on a specific CT scanner. The comparison with other methods provides encouraging results, with residual SPR error on human tissue within 1%. The distinctive features of the proposed method are its simplicity and the generality of the conversion functions.
Calculation of phonon dispersion relation using new correlation functional

NASA Astrophysics Data System (ADS)

Jitropas, Ukrit; Hsu, Chung-Hao

2017-06-01

To extend the use of Local Density Approximation (LDA), a new analytical correlation functional is introduced. Correlation energy is an essential ingredient within density functional theory and used to determine ground state energy and other properties including phonon dispersion relation. Except for high and low density limit, the general expression of correlation energy is unknown. The approximation approach is therefore required. The accuracy of the modelling system depends on the quality of correlation energy approximation. Typical correlation functionals used in LDA such as Vosko-Wilk-Nusair (VWN) and Perdew-Wang (PW) were obtained from parameterizing the near-exact quantum Monte Carlo data of Ceperley and Alder. These functionals are presented in complex form and inconvenient to implement. Alternatively, the latest published formula of Chachiyo correlation functional provides a comparable result for those much more complicated functionals. In addition, it provides more predictive power based on the first principle approach, not fitting functionals. Nevertheless, the performance of Chachiyo formula for calculating phonon dispersion relation (a key to the thermal properties of materials) has not been tested yet. Here, the implementation of new correlation functional to calculate phonon dispersion relation is initiated. The accuracy and its validity will be explored.
A targeted genotyping approach enhances identification of variants in taste receptor and appetite/reward genes of potential functional importance for obesity-related porcine traits.

PubMed

Cirera, S; Clop, A; Jacobsen, M J; Guerin, M; Lesnik, P; Jørgensen, C B; Fredholm, M; Karlskov-Mortensen, P

2018-04-01

Taste receptors (TASRs) and appetite and reward (AR) mechanisms influence eating behaviour, which in turn affects food intake and risk of obesity. In a previous study, we used next generation sequencing to identify potentially functional mutations in TASR and AR genes and found indications for genetic associations between identified variants and growth and fat deposition in a subgroup of animals (n = 38) from the UNIK resource pig population. This population was created for studying obesity and obesity-related diseases. In the present study we validated results from our previous study by investigating genetic associations between 24 selected single nucleotide variants in TASR and AR gene variants and 35 phenotypes describing obesity and metabolism in the entire UNIK population (n = 564). Fifteen variants showed significant association with specific obesity-related phenotypes after Bonferroni correction. Six of the 15 genes, namely SIM1, FOS, TAS2R4, TAS2R9, MCHR2 and LEPR, showed good correlation between known biological function and associated phenotype. We verified a genetic association between potentially functional variants in TASR/AR genes and growth/obesity and conclude that the combination of identification of potentially functional variants by next generation sequencing followed by targeted genotyping and association studies is a powerful and cost-effective approach for increasing the power of genetic association studies. © 2018 Stichting International Foundation for Animal Genetics.
A method for the estimation of the significance of cross-correlations in unevenly sampled red-noise time series

NASA Astrophysics Data System (ADS)

Max-Moerbeck, W.; Richards, J. L.; Hovatta, T.; Pavlidou, V.; Pearson, T. J.; Readhead, A. C. S.

2014-11-01

We present a practical implementation of a Monte Carlo method to estimate the significance of cross-correlations in unevenly sampled time series of data, whose statistical properties are modelled with a simple power-law power spectral density. This implementation builds on published methods; we introduce a number of improvements in the normalization of the cross-correlation function estimate and a bootstrap method for estimating the significance of the cross-correlations. A closely related matter is the estimation of a model for the light curves, which is critical for the significance estimates. We present a graphical and quantitative demonstration that uses simulations to show how common it is to get high cross-correlations for unrelated light curves with steep power spectral densities. This demonstration highlights the dangers of interpreting them as signs of a physical connection. We show that by using interpolation and the Hanning sampling window function we are able to reduce the effects of red-noise leakage and to recover steep simple power-law power spectral densities. We also introduce the use of a Neyman construction for the estimation of the errors in the power-law index of the power spectral density. This method provides a consistent way to estimate the significance of cross-correlations in unevenly sampled time series of data.
Retrofits Convert Gas Vehicles into Hybrids

NASA Technical Reports Server (NTRS)

2012-01-01

Successful space missions can rarely be attributed to a single thing. Rather, they are the result of a system of systems: integrated elements functioning effectively in their individual roles and together with related components, then those systems interacting with and supporting other systems to form a collaborative whole - from the spacecraft itself to the engineering and research teams that design and build it. An example is found in spacecraft power systems. Unlike a gas-powered car or a battery-powered laptop, most spacecraft are powered by multiple energy sources - such as photovoltaic panels, fuel cells, and batteries - working in tandem to ensure the spacecraft functions throughout the course of a mission. As with any system, the appropriate combination of elements and the method of their management are key to high performance and efficiency. One initiative at Glenn Research Center, the Hybrid Power Management (HPM) program, focused on joining new and mature technologies for optimal power systems applications in space and on Earth, with the goal not only to develop ultra-efficient space power systems, but to advance HPM to address global energy issues. The HPM program emerged from Glenn s long history of electric vehicle research dating back to the 1970s, including the NASA Hybrid Electric Transit Bus (HETB) project in the 1990s, which was the largest vehicle to use supercapacitor energy storage.
The effects of working memory training on functional brain network efficiency.

PubMed

Langer, Nicolas; von Bastian, Claudia C; Wirz, Helen; Oberauer, Klaus; Jäncke, Lutz

2013-10-01

The human brain is a highly interconnected network. Recent studies have shown that the functional and anatomical features of this network are organized in an efficient small-world manner that confers high efficiency of information processing at relatively low connection cost. However, it has been unclear how the architecture of functional brain networks is related to performance in working memory (WM) tasks and if these networks can be modified by WM training. Therefore, we conducted a double-blind training study enrolling 66 young adults. Half of the subjects practiced three WM tasks and were compared to an active control group practicing three tasks with low WM demand. High-density resting-state electroencephalography (EEG) was recorded before and after training to analyze graph-theoretical functional network characteristics at an intracortical level. WM performance was uniquely correlated with power in the theta frequency, and theta power was increased by WM training. Moreover, the better a person's WM performance, the more their network exhibited small-world topology. WM training shifted network characteristics in the direction of high performers, showing increased small-worldness within a distributed fronto-parietal network. Taken together, this is the first longitudinal study that provides evidence for the plasticity of the functional brain network underlying WM. Copyright © 2013 Elsevier Ltd. All rights reserved.
Power Laws from Linear Neuronal Cable Theory: Power Spectral Densities of the Soma Potential, Soma Membrane Current and Single-Neuron Contribution to the EEG

PubMed Central

Pettersen, Klas H.; Lindén, Henrik; Tetzlaff, Tom; Einevoll, Gaute T.

2014-01-01

Power laws, that is, power spectral densities (PSDs) exhibiting behavior for large frequencies f, have been observed both in microscopic (neural membrane potentials and currents) and macroscopic (electroencephalography; EEG) recordings. While complex network behavior has been suggested to be at the root of this phenomenon, we here demonstrate a possible origin of such power laws in the biophysical properties of single neurons described by the standard cable equation. Taking advantage of the analytical tractability of the so called ball and stick neuron model, we derive general expressions for the PSD transfer functions for a set of measures of neuronal activity: the soma membrane current, the current-dipole moment (corresponding to the single-neuron EEG contribution), and the soma membrane potential. These PSD transfer functions relate the PSDs of the respective measurements to the PSDs of the noisy input currents. With homogeneously distributed input currents across the neuronal membrane we find that all PSD transfer functions express asymptotic high-frequency power laws with power-law exponents analytically identified as for the soma membrane current, for the current-dipole moment, and for the soma membrane potential. Comparison with available data suggests that the apparent power laws observed in the high-frequency end of the PSD spectra may stem from uncorrelated current sources which are homogeneously distributed across the neural membranes and themselves exhibit pink () noise distributions. While the PSD noise spectra at low frequencies may be dominated by synaptic noise, our findings suggest that the high-frequency power laws may originate in noise from intrinsic ion channels. The significance of this finding goes beyond neuroscience as it demonstrates how power laws with a wide range of values for the power-law exponent α may arise from a simple, linear partial differential equation. PMID:25393030
Power laws from linear neuronal cable theory: power spectral densities of the soma potential, soma membrane current and single-neuron contribution to the EEG.

PubMed

Pettersen, Klas H; Lindén, Henrik; Tetzlaff, Tom; Einevoll, Gaute T

2014-11-01

Power laws, that is, power spectral densities (PSDs) exhibiting 1/f(α) behavior for large frequencies f, have been observed both in microscopic (neural membrane potentials and currents) and macroscopic (electroencephalography; EEG) recordings. While complex network behavior has been suggested to be at the root of this phenomenon, we here demonstrate a possible origin of such power laws in the biophysical properties of single neurons described by the standard cable equation. Taking advantage of the analytical tractability of the so called ball and stick neuron model, we derive general expressions for the PSD transfer functions for a set of measures of neuronal activity: the soma membrane current, the current-dipole moment (corresponding to the single-neuron EEG contribution), and the soma membrane potential. These PSD transfer functions relate the PSDs of the respective measurements to the PSDs of the noisy input currents. With homogeneously distributed input currents across the neuronal membrane we find that all PSD transfer functions express asymptotic high-frequency 1/f(α) power laws with power-law exponents analytically identified as α∞(I) = 1/2 for the soma membrane current, α∞(p) = 3/2 for the current-dipole moment, and α∞(V) = 2 for the soma membrane potential. Comparison with available data suggests that the apparent power laws observed in the high-frequency end of the PSD spectra may stem from uncorrelated current sources which are homogeneously distributed across the neural membranes and themselves exhibit pink (1/f) noise distributions. While the PSD noise spectra at low frequencies may be dominated by synaptic noise, our findings suggest that the high-frequency power laws may originate in noise from intrinsic ion channels. The significance of this finding goes beyond neuroscience as it demonstrates how 1/f(α) power laws with a wide range of values for the power-law exponent α may arise from a simple, linear partial differential equation.
Dimensional Analysis of Impulse Loading Resulting from Detonation of Shallow-Buried Charges

DTIC Science & Technology

2013-01-01

lines running along the floor, floor-bolted seats , ammunition storage racks, power-train lines, etc.). MMMS 9,3 368 Traditionally, the floor-rupture...The power of dimensional analysis is that the functional relations offered are generalized, i.e. the effect of geometrical, kinematic , ambient, loading... ejected vdet Explosive detonation velocity L/T A new quantity added which controls the time of sand-overburden bubble burst Charge/plate positioning
Distribution of the Crystalline Lens Power In Vivo as a Function of Age.

PubMed

Jongenelen, Sien; Rozema, Jos J; Tassignon, Marie-José

2015-11-01

To observe the age-related changes in crystalline lens power in vivo in a noncataractous European population. Data were obtained though Project Gullstrand, a multicenter population study with data from healthy phakic subjects between 20 and 85 years old. One randomly selected eye per subject was used. Lens power was calculated using the modified Bennett-Rabbetts method, using biometry data from an autorefractometer, Oculus Pentacam, and Haag-Streit Lenstar. The study included 1069 Caucasian subjects (490 men, 579 women) with a mean age of 44.2 ± 14.2 years and mean lens power of 24.96 ± 2.18 diopters (D). The average lens power showed a statistically significant decrease as a function of age, with a steeper rate of decrease after the age of 55. The highest crystalline lens power was found in emmetropic eyes and eyes with a short axial length. The correlation of lens power with different refractive components was statistically significant for axial length (r = -0.523, P < 0.01) and anterior chamber depth (r = -0.161, P < 0.01), but not for spherical equivalent and corneal power (P > 0.05). This in vivo study showed a monotonous decrease in crystalline lens power with age, with a steeper decline after 55 years. While this finding fundamentally concurs with previous in vivo studies, it is at odds with studies performed on donor eyes that reported lens power increases after the age of 55.
Force-velocity relationship in cycling revisited: benefit of two-dimensional pedal forces analysis.

PubMed

Dorel, Sylvain; Couturier, Antoine; Lacour, Jean-René; Vandewalle, Henry; Hautier, Christophe; Hug, François

2010-06-01

Maximal cycling exercise has been widely used to describe the power-velocity characteristics of lower-limb extensor muscles. This study investigated the contribution of each functional sector (i.e., extension, flexion, and transitions sectors) on the total force produced over a complete pedaling cycle. We also examined the ratio of effective force to the total pedal force, termed index of mechanical effectiveness (IE), in explaining differences in power between subjects. Two-dimensional pedal forces and crank angles were measured during a cycling force-velocity test performed by 14 active men. Mean values of forces, power output, and IE over four functional angular sectors were assessed: top = 330 degrees -30 degrees , downstroke = 30 degrees -150 degrees , bottom = 150 degrees -210 degrees , and upstroke = 210 degrees -330 degrees . Linear and quadratic force-velocity and power-velocity relationships were obtained for downstroke and upstroke. Maximal power output (Pmax) generated over these two sectors represented, respectively, 73.6% +/- 2.6% and 10.3% +/- 1.8% of Pmax assessed over the entire cycle. In the whole group, Pmax over the complete cycle was significantly related to Pmax during the downstroke and upstroke. IE significantly decreased with pedaling rate, especially in bottom and upstroke. There were significant relationships between power output and IE for top and upstroke when the pedaling rate was below or around the optimal value and in all the sectors at very high cadences. Although data from force-velocity test primarily characterize the muscular function involved in the downstroke phase, they also reflect the flexor muscles' ability to actively pull on the pedal during the upstroke. IE influences the power output in the upstroke phase and near the top dead center, and IE accounts for differences in power between subjects at high pedaling rates.
Assessment of body-powered upper limb prostheses by able-bodied subjects, using the Box and Blocks Test and the Nine-Hole Peg Test.

PubMed

Haverkate, Liz; Smit, Gerwin; Plettenburg, Dick H

2016-02-01

The functional performance of currently available body-powered prostheses is unknown. The goal of this study was to objectively assess and compare the functional performance of three commonly used body-powered upper limb terminal devices. Experimental trial. A total of 21 able-bodied subjects (n = 21, age = 22 ± 2) tested three different terminal devices: TRS voluntary closing Hook Grip 2S, Otto Bock voluntary opening hand and Hosmer Model 5XA hook, using a prosthesis simulator. All subjects used each terminal device nine times in two functional tests: the Nine-Hole Peg Test and the Box and Blocks Test. Significant differences were found between the different terminal devices and their scores on the Nine-Hole Peg Test and the Box and Blocks Test. The Hosmer hook scored best in both tests. The TRS Hook Grip 2S scored second best. The Otto Bock hand showed the lowest scores. This study is a first step in the comparison of functional performances of body-powered prostheses. The data can be used as a reference value, to assess the performance of a terminal device or an amputee. The measured scores enable the comparison of the performance of a prosthesis user and his or her terminal device relative to standard scores. © The International Society for Prosthetics and Orthotics 2014.
Aerobic power and lean mass are indicators of competitive sprint performance among elite female cross-country skiers.

PubMed

Carlsson, Tomas; Tonkonogi, Michail; Carlsson, Magnus

2016-01-01

The purpose of this study was to establish the optimal allometric models to predict International Ski Federation's ski-ranking points for sprint competitions (FISsprint) among elite female cross-country skiers based on maximal oxygen uptake ( [Formula: see text]) and lean mass (LM). Ten elite female cross-country skiers (age: 24.5±2.8 years [mean ± SD]) completed a treadmill roller-skiing test to determine [Formula: see text] (ie, aerobic power) using the diagonal stride technique, whereas LM (ie, a surrogate indicator of anaerobic capacity) was determined by dual-emission X-ray anthropometry. The subjects' FISsprint were used as competitive performance measures. Power function modeling was used to predict the skiers' FISsprint based on [Formula: see text], LM, and body mass. The subjects' test and performance data were as follows: [Formula: see text], 4.0±0.3 L min -1 ; LM, 48.9±4.4 kg; body mass, 64.0±5.2 kg; and FISsprint, 116.4±59.6 points. The following power function models were established for the prediction of FISsprint: [Formula: see text] and 6.95 × 10 10 · LM -5.25 ; these models explained 66% ( P =0.0043) and 52% ( P =0.019), respectively, of the variance in the FISsprint. Body mass failed to contribute to both models; hence, the models are based on [Formula: see text] and LM expressed absolutely. The results demonstrate that the physiological variables that reflect aerobic power and anaerobic capacity are important indicators of competitive sprint performance among elite female skiers. To accurately indicate performance capability among elite female skiers, the presented power function models should be used. Skiers whose [Formula: see text] differs by 1% will differ in their FISsprint by 5.8%, whereas the corresponding 1% difference in LM is related to an FISsprint difference of 5.1%, where both differences are in favor of the skier with higher [Formula: see text] or LM. It is recommended that coaches use the absolute expression of these variables to monitor skiers' performance-related training adaptations linked to changes in aerobic power and anaerobic capacity.
Calculating realistic voltages across the US power grid utilizing measured impedances and magnetic fields

NASA Astrophysics Data System (ADS)

Lucas, G.; Love, J. J.; Kelbert, A.; Bedrosian, P.; Rigler, E. J.

2017-12-01

Space weather induces significant geoelectric fields within Earth's subsurface that can adversely affect electric power grids. The complex interaction between space weather and the solid Earth has traditionally been approached with the use of simple 1-D impedance functions relating the inducing magnetic field to the induced geoelectric field. Ongoing data collection through the NSF EarthScope program has produced measured impedance data across much of the continental US. In this work, impedance data are convolved with magnetic field variations, obtained from USGS magnetic observatories, during a geomagnetic storm. This convolution produces geoelectric fields within the earth. These geoelectric fields are then integrated across power transmission lines to determine the voltage generated within each power line as a function of time during a geomagnetic storm. The voltages generated within the electric power grid will be shown for several historic geomagnetic storms. The estimated voltages calculated from 1-D and 3-D impedances differ by more than 100 V across some transmission lines. In combination with grounding resistance data and network topology, these voltage estimates can be utilized by power companies to estimate geomagnetically-induced currents throughout the network. These voltage estimates can provide information on which power lines are most vulnerable to geomagnetic storms, and assist power grid companies investigating where to install additional protections within their grid.
Testosterone Dose-Response Relationships in Hysterectomized Women with and without Oophorectomy: Effects on Sexual Function, Body Composition, Muscle Performance and Physical Function in a Randomized Trial

PubMed Central

Huang, Grace; Basaria, Shehzad; Travison, Thomas G.; Ho, Matthew H.; Davda, Maithili; Mazer, Norman A.; Miciek, Renee; Knapp, Philip E.; Zhang, Anqi; Collins, Lauren; Ursino, Monica; Appleman, Erica; Dzekov, Connie; Stroh, Helene; Ouellette, Miranda; Rundell, Tyler; Baby, Merilyn; Bhatia, Narender N.; Khorram, Omid; Friedman, Theodore; Storer, Thomas W.; Bhasin, Shalender

2015-01-01

Objective To determine dose-dependent effects of testosterone on sexual function, body composition, muscle performance, and physical function in hysterectomized women with and without oophorectomy. Methods 71 menopausal women who previously underwent hysterectomy with or without oophorectomy with total testosterone<31ng/dl or free testosterone<3.5 pg/ml received a standardized transdermal estradiol regimen during the 12-week run-in period, and were then randomized to receive weekly IM injections of placebo, or 3, 6.25, 12.5 or 25 mg testosterone enanthate for 24 weeks. Total and free testosterone levels were measured by LC-MS/MS and equilibrium dialysis, respectively. The primary outcome was change in sexual function measured using Brief Index of Sexual Function (BISF-W); Secondary outcomes included changes in sexual activity, sexual distress, DeRogatis Inventory of Sexual Function, lean (LBM) and fat mass, muscle strength and power, and physical function. Results 71 women were randomized; five groups were similar at baseline. 62 women with analyzable data for the primary outcome were included in the final analysis. Mean on-treatment total testosterone concentrations were 19, 78, 102, 128 and 210ng/dl in the placebo, 3, 6.25, 12.5 and 25-mg groups, respectively. Changes in composite BISF-W scores, thoughts-desire, arousal, frequency of sexual activity, LBM, chest-press power and loaded stair-climb power were significantly related to increases in free testosterone concentrations; changes were significantly greater in women assigned to the 25-mg group when compared to placebo but not at the lower dose groups. Sexual activity increased by 2.7 encounters per week in 25-mg group. Frequency of androgenic adverse events was low. Conclusion Testosterone administration in hysterectomized women with and without oophorectomy for 24-weeks was associated with dose and concentration-dependent gains in several domains of sexual function, LBM, chest-press power and loaded stair-climb power. Long-term trials are needed to weigh improvements in these outcomes against potential long-term adverse effects. PMID:24281237
The hormonal correlates of implicit power motivation

PubMed Central

Stanton, Steven J.; Schultheiss, Oliver C.

2009-01-01

Attempts to link testosterone to dominance dispositions using self-report measures of dominance have yielded inconsistent findings. Similarly, attempts to link testosterone changes to a situational outcome like winning or losing a dominance contest have yielded inconsistent findings. However, research has consistently shown that an indirect measure of an individual’s dominance disposition, implicit power motivation, is positively related to baseline testosterone levels and, in interaction with situational outcomes, predicts testosterone changes. We propose a hormonal model of implicit power motivation that describes how testosterone levels change as an interactive function of individuals’ implicit power motivation and dominance situations. We also propose that estradiol, and not testosterone, plays a key role in dominance motivation in women. PMID:20161646

Portability scenarios for intelligent robotic control agent software

NASA Astrophysics Data System (ADS)

Straub, Jeremy

2014-06-01

Portability scenarios are critical in ensuring that a piece of AI control software will run effectively across the collection of craft that it is required to control. This paper presents scenarios for control software that is designed to control multiple craft with heterogeneous movement and functional characteristics. For each prospective target-craft type, its capabilities, mission function, location, communications capabilities and power profile are presented and performance characteristics are reviewed. This work will inform future work related to decision making related to software capabilities, hardware control capabilities and processing requirements.
Measures of static postural control moderate the association of strength and power with functional dynamic balance.

PubMed

Forte, Roberta; Boreham, Colin A G; De Vito, Giuseppe; Ditroilo, Massimiliano; Pesce, Caterina

2014-12-01

Age-related reductions in strength and power are considered to negatively impact balance control, but the existence of a direct association is still an issue of debate. This is possibly due to the fact that balance assessment is complex, reflects different underlying physiologic mechanisms and involves quantitative measurements of postural sway or timing of performance during balance tasks. The present study evaluated the moderator effect of static postural control on the association of power and strength with dynamic balance tasks. Fifty-seven healthy 65-75 year old individuals performed tests of dynamic functional balance (walking speed under different conditions) and of strength, power and static postural control. Dynamic balance performance (walking speed) was associated with lower limb strength and power, as well as postural control under conditions requiring postural adjustments (narrow surface walking r(2) = 0.31, p < 0.001). An interaction effect between strength and static postural control was found with narrow surface walking and talking while walking (change of β 0.980, p < 0.001 in strength for 1 SD improvements in static postural control for narrow walking, and [Formula: see text] -0.730, p < 0.01 in talking while walking). These results indicate that good static postural control facilitates the utilisation of lower limb strength to better perform complex, dynamic functional balance tasks. Practical implications for assessment and training are discussed.
Relationship of medial gastrocnemius relative fascicle excursion and ankle joint power and work performance during gait in typically developing children: A cross-sectional study.

PubMed

Martín Lorenzo, Teresa; Albi Rodríguez, Gustavo; Rocon, Eduardo; Martínez Caballero, Ignacio; Lerma Lara, Sergio

2017-07-01

Muscle fascicles lengthen in response to chronic passive stretch through in-series sarcomere addition in order to maintain an optimum sarcomere length. In turn, the muscles' force generating capacity, maximum excursion, and contraction velocity is enhanced. Thus, longer fascicles suggest a greater capacity to develop joint power and work. However, static fascicle length measurements may not be taking sarcomere length differences into account. Thus, we considered relative fascicle excursions through passive ankle dorsiflexion may better correlate with the capacity to generate joint power and work than fascicle length. Therefore, the aim of the present study was to determine if medial gastrocnemius relative fascicle excursions correlate with ankle joint power and work generation during gait in typically developing children. A sample of typically developing children (n = 10) were recruited for this study and data analysis was carried out on 20 legs. Medial gastrocnemius relative fascicle excursion from resting joint angle to maximum dorsiflexion was estimated from trigonometric relations of medial gastrocnemius pennation angle and thickness obtained from B-mode real-time ultrasonography. Furthermore, a three-dimensional motion capture system was used to obtain ankle joint work and power during the stance phase of gait. Significant correlations were found between relative fascicle excursion and peak power absorption (-) r(14) = -0.61, P = .012 accounting for 31% variability, positive work r(18) = 0.56, P = .021 accounting for 31% variability, and late stance positive work r(15) = 0.51, P = .037 accounting for 26% variability. The large unexplained variance may be attributed to mechanics of neighboring structures (e.g., soleus or Achilles tendon mechanics) and proximal joint kinetics which may also contribute to ankle joint power and work performance, and were not taken into account. Further studies are encouraged to provide greater insight on the relationship between relative fascicle excursions and joint function.
Relationship of medial gastrocnemius relative fascicle excursion and ankle joint power and work performance during gait in typically developing children

PubMed Central

Martín Lorenzo, Teresa; Albi Rodríguez, Gustavo; Rocon, Eduardo; Martínez Caballero, Ignacio; Lerma Lara, Sergio

2017-01-01

Abstract Muscle fascicles lengthen in response to chronic passive stretch through in-series sarcomere addition in order to maintain an optimum sarcomere length. In turn, the muscles’ force generating capacity, maximum excursion, and contraction velocity is enhanced. Thus, longer fascicles suggest a greater capacity to develop joint power and work. However, static fascicle length measurements may not be taking sarcomere length differences into account. Thus, we considered relative fascicle excursions through passive ankle dorsiflexion may better correlate with the capacity to generate joint power and work than fascicle length. Therefore, the aim of the present study was to determine if medial gastrocnemius relative fascicle excursions correlate with ankle joint power and work generation during gait in typically developing children. A sample of typically developing children (n = 10) were recruited for this study and data analysis was carried out on 20 legs. Medial gastrocnemius relative fascicle excursion from resting joint angle to maximum dorsiflexion was estimated from trigonometric relations of medial gastrocnemius pennation angle and thickness obtained from B-mode real-time ultrasonography. Furthermore, a three-dimensional motion capture system was used to obtain ankle joint work and power during the stance phase of gait. Significant correlations were found between relative fascicle excursion and peak power absorption (–) r(14) = −0.61, P = .012 accounting for 31% variability, positive work r(18) = 0.56, P = .021 accounting for 31% variability, and late stance positive work r(15) = 0.51, P = .037 accounting for 26% variability. The large unexplained variance may be attributed to mechanics of neighboring structures (e.g., soleus or Achilles tendon mechanics) and proximal joint kinetics which may also contribute to ankle joint power and work performance, and were not taken into account. Further studies are encouraged to provide greater insight on the relationship between relative fascicle excursions and joint function. PMID:28723790
The effect of obesity on the contractile performance of isolated mouse soleus, EDL, and diaphragm muscles.

PubMed

Tallis, Jason; Hill, Cameron; James, Rob S; Cox, Val M; Seebacher, Frank

2017-01-01

Obesity affects the major metabolic and cellular processes involved in skeletal muscle contractility. Surprisingly, the effect of obesity on isolated skeletal muscle performance remains unresolved. The present study is the first to examine the muscle-specific changes in contractility following dietary-induced obesity using an isolated muscle work-loop (WL) model that more closely represents in vivo muscle performance. Following 16-wk high-calorific feeding, soleus (SOL), extensor digitorum longus (EDL), and diaphragm (DIA) were isolated from female (CD-1) mice, and contractile performance was compared against a lean control group. Obese SOL produced greater isometric force; however, isometric stress (force per unit muscle area), absolute WL power, and normalized WL power (watts per kilogram muscle mass) were unaffected. Maximal isometric force and absolute WL power of the EDL were similar between groups. For both EDL and DIA, isometric stress and normalized WL power were reduced in the obese groups. Obesity caused a significant reduction in fatigue resistance in all cases. Our findings demonstrate a muscle-specific reduction in contractile performance and muscle quality that is likely related to in vivo mechanical role, fiber type, and metabolic profile, which may in part be related to changes in myosin heavy chain expression and AMP-activated protein kinase activity. These results infer that, beyond the additional requirement of moving a larger body mass, functional performance and quality of life may be further limited by poor muscle function in obese individuals. As such, a reduction in muscle performance may be a substantial contributor to the negative cycle of obesity. The effect of obesity on isolated muscle function is surprisingly underresearched. The present study is the first to examine the effects of obesity on isolated muscle performance using a method that more closely represents real-world muscle function. This work uniquely establishes a muscle-specific profile of mechanical changes in relation to underpinning mechanisms. These findings may be important to understanding the negative cycle of obesity and in designing interventions for improving weight status. Copyright © 2017 the American Physiological Society.
A transition calculus for Boolean functions. [logic circuit analysis

NASA Technical Reports Server (NTRS)

Tucker, J. H.; Bennett, A. W.

1974-01-01

A transition calculus is presented for analyzing the effect of input changes on the output of logic circuits. The method is closely related to the Boolean difference, but it is more powerful. Both differentiation and integration are considered.
Rotary drum separator system

NASA Technical Reports Server (NTRS)

Barone, Michael R. (Inventor); Murdoch, Karen (Inventor); Scull, Timothy D. (Inventor); Fort, James H. (Inventor)

2009-01-01

A rotary phase separator system generally includes a step-shaped rotary drum separator (RDS) and a motor assembly. The aspect ratio of the stepped drum minimizes power for both the accumulating and pumping functions. The accumulator section of the RDS has a relatively small diameter to minimize power losses within an axial length to define significant volume for accumulation. The pumping section of the RDS has a larger diameter to increase pumping head but has a shorter axial length to minimize power losses. The motor assembly drives the RDS at a low speed for separating and accumulating and a higher speed for pumping.
Lung function not affected by asbestos exposure in workers with normal Computed Tomography scan.

PubMed

Schikowsky, Christian; Felten, Michael K; Eisenhawer, Christian; Das, Marco; Kraus, Thomas

2017-05-01

It has been suggested that asbestos exposure affects lung function, even in the absence of asbestos-related pulmonary interstitial or pleural changes or emphysema. We analyzed associations between well-known asbestos-related risk factors, such as individual cumulative asbestos exposure, and key lung function parameters in formerly asbestos-exposed power industry workers (N = 207) with normal CT scans. For this, we excluded participants with emphysema, fibrosis, pleural changes, or any combination of these. The lung function parameters of FVC, FEV1, DLCO/VA, and airway resistance were significantly associated with the burden of smoking, BMI and years since end of exposure (only DLCO/VA). However, they were not affected by factors directly related to amount (eg, cumulative exposure) or duration of asbestos exposure. Our results confirm the well-known correlation between lung function, smoking habits, and BMI. However, we found no significant association between lung function and asbestos exposure. © 2017 Wiley Periodicals, Inc.
Characterization of zero-bias microwave diode power detectors at cryogenic temperature.

PubMed

Giordano, Vincent; Fluhr, Christophe; Dubois, Benoît; Rubiola, Enrico

2016-08-01

We present the characterization of commercial tunnel diode low-level microwave power detectors at room and cryogenic temperatures. The sensitivity as well as the output voltage noise of the tunnel diodes is measured as functions of the applied microwave power. We highlight strong variations of the diode characteristics when the applied microwave power is higher than a few microwatts. For a diode operating at 4 K, the differential gain increases from 1000 V/W to about 4500 V/W when the power passes from -30 dBm to -20 dBm. The diode white noise floor is equivalent to a Noise Equivalent Power of 0.8 pW/Hz and 8 pW/Hz at 4 K and 300 K, respectively. Its flicker noise is equivalent to a relative amplitude noise power spectral density Sα(1 Hz) = - 120 dB/Hz at 4 K. Flicker noise is 10 dB higher at room temperature.
Extracting functionally feedforward networks from a population of spiking neurons

PubMed Central

Vincent, Kathleen; Tauskela, Joseph S.; Thivierge, Jean-Philippe

2012-01-01

Neuronal avalanches are a ubiquitous form of activity characterized by spontaneous bursts whose size distribution follows a power-law. Recent theoretical models have replicated power-law avalanches by assuming the presence of functionally feedforward connections (FFCs) in the underlying dynamics of the system. Accordingly, avalanches are generated by a feedforward chain of activation that persists despite being embedded in a larger, massively recurrent circuit. However, it is unclear to what extent networks of living neurons that exhibit power-law avalanches rely on FFCs. Here, we employed a computational approach to reconstruct the functional connectivity of cultured cortical neurons plated on multielectrode arrays (MEAs) and investigated whether pharmacologically induced alterations in avalanche dynamics are accompanied by changes in FFCs. This approach begins by extracting a functional network of directed links between pairs of neurons, and then evaluates the strength of FFCs using Schur decomposition. In a first step, we examined the ability of this approach to extract FFCs from simulated spiking neurons. The strength of FFCs obtained in strictly feedforward networks diminished monotonically as links were gradually rewired at random. Next, we estimated the FFCs of spontaneously active cortical neuron cultures in the presence of either a control medium, a GABAA receptor antagonist (PTX), or an AMPA receptor antagonist combined with an NMDA receptor antagonist (APV/DNQX). The distribution of avalanche sizes in these cultures was modulated by this pharmacology, with a shallower power-law under PTX (due to the prominence of larger avalanches) and a steeper power-law under APV/DNQX (due to avalanches recruiting fewer neurons) relative to control cultures. The strength of FFCs increased in networks after application of PTX, consistent with an amplification of feedforward activity during avalanches. Conversely, FFCs decreased after application of APV/DNQX, consistent with fading feedforward activation. The observed alterations in FFCs provide experimental support for recent theoretical work linking power-law avalanches to the feedforward organization of functional connections in local neuronal circuits. PMID:23091458
Extracting functionally feedforward networks from a population of spiking neurons.

PubMed

Vincent, Kathleen; Tauskela, Joseph S; Thivierge, Jean-Philippe

2012-01-01

Neuronal avalanches are a ubiquitous form of activity characterized by spontaneous bursts whose size distribution follows a power-law. Recent theoretical models have replicated power-law avalanches by assuming the presence of functionally feedforward connections (FFCs) in the underlying dynamics of the system. Accordingly, avalanches are generated by a feedforward chain of activation that persists despite being embedded in a larger, massively recurrent circuit. However, it is unclear to what extent networks of living neurons that exhibit power-law avalanches rely on FFCs. Here, we employed a computational approach to reconstruct the functional connectivity of cultured cortical neurons plated on multielectrode arrays (MEAs) and investigated whether pharmacologically induced alterations in avalanche dynamics are accompanied by changes in FFCs. This approach begins by extracting a functional network of directed links between pairs of neurons, and then evaluates the strength of FFCs using Schur decomposition. In a first step, we examined the ability of this approach to extract FFCs from simulated spiking neurons. The strength of FFCs obtained in strictly feedforward networks diminished monotonically as links were gradually rewired at random. Next, we estimated the FFCs of spontaneously active cortical neuron cultures in the presence of either a control medium, a GABA(A) receptor antagonist (PTX), or an AMPA receptor antagonist combined with an NMDA receptor antagonist (APV/DNQX). The distribution of avalanche sizes in these cultures was modulated by this pharmacology, with a shallower power-law under PTX (due to the prominence of larger avalanches) and a steeper power-law under APV/DNQX (due to avalanches recruiting fewer neurons) relative to control cultures. The strength of FFCs increased in networks after application of PTX, consistent with an amplification of feedforward activity during avalanches. Conversely, FFCs decreased after application of APV/DNQX, consistent with fading feedforward activation. The observed alterations in FFCs provide experimental support for recent theoretical work linking power-law avalanches to the feedforward organization of functional connections in local neuronal circuits.
Evolution of the linear-polarization-angle-dependence of the radiation-induced magnetoresistance-oscillations with microwave power

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

Ye, Tianyu; Mani, R. G.; Wegscheider, W.

2014-11-10

We examine the role of the microwave power in the linear polarization angle dependence of the microwave radiation induced magnetoresistance oscillations observed in the high mobility GaAs/AlGaAs two dimensional electron system. The diagonal resistance R{sub xx} was measured at the fixed magnetic fields of the photo-excited oscillatory extrema of R{sub xx} as a function of both the microwave power, P, and the linear polarization angle, θ. Color contour plots of such measurements demonstrate the evolution of the lineshape of R{sub xx} versus θ with increasing microwave power. We report that the non-linear power dependence of the amplitude of the radiation-inducedmore » magnetoresistance oscillations distorts the cosine-square relation between R{sub xx} and θ at high power.« less
Attributes and National Behavior, Part 2: Modern International Relations Monograph Series. Relative Status-Field Theory, Results for Conflict, TU Actors, 1966-1969, An Inventory of Findings.

ERIC Educational Resources Information Center

Vincent, Jack E.

This monograph presents findings from an analysis of data on international conflict over a three-year period. Part of a large scale research project to test various theories with regard to their power in analyzing international relations, this monograph presents the computer printout of data on the application of discriminant function analysis of…
Attributes and National Behavior, Part 2: Modern International Relations Monograph Series. Relative Status-Field Theory, Results for Cooperation, UU Actors, 1966-1969, An Inventory of Findings.

ERIC Educational Resources Information Center

Vincent, Jack E.

This monograph presents findings from an analysis of data on international cooperation over a three-year period. Part of a large scale research project to test various theories with regard to their power in analyzing international relations, this monograph presents the computer printout of data on the application of discriminant function analysis…
Functional connectivity and activity of white matter in somatosensory pathways under tactile stimulations.

PubMed

Wu, Xi; Yang, Zhipeng; Bailey, Stephen K; Zhou, Jiliu; Cutting, Laurie E; Gore, John C; Ding, Zhaohua

2017-05-15

Functional MRI has proven to be effective in detecting neural activity in brain cortices on the basis of blood oxygenation level dependent (BOLD) contrast, but has relatively poor sensitivity for detecting neural activity in white matter. To demonstrate that BOLD signals in white matter are detectable and contain information on neural activity, we stimulated the somatosensory system and examined distributions of BOLD signals in related white matter pathways. The temporal correlation profiles and frequency contents of BOLD signals were compared between stimulation and resting conditions, and between relevant white matter fibers and background regions, as well as between left and right side stimulations. Quantitative analyses show that, overall, MR signals from white matter fiber bundles in the somatosensory system exhibited significantly greater temporal correlations with the primary sensory cortex and greater signal power during tactile stimulations than in a resting state, and were stronger than corresponding measurements for background white matter both during stimulations and in a resting state. The temporal correlation and signal power under stimulation were found to be twice those observed from the same bundle in a resting state, and bore clear relations with the side of stimuli. These indicate that BOLD signals in white matter fibers encode neural activity related to their functional roles connecting cortical volumes, which are detectable with appropriate methods. Copyright © 2017 Elsevier Inc. All rights reserved.
Entangled scalar and tensor fluctuations during inflation

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

Collins, Hael; Vardanyan, Tereza

2016-11-29

We show how the choice of an inflationary state that entangles scalar and tensor fluctuations affects the angular two-point correlation functions of the T, E, and B modes of the cosmic microwave background. The propagators for a state starting with some general quadratic entanglement are solved exactly, leading to predictions for the primordial scalar-scalar, tensor-tensor, and scalar-tensor power spectra. These power spectra are expressed in terms of general functions that describe the entangling structure of the initial state relative to the standard Bunch-Davies vacuum. We illustrate how such a state would modify the angular correlations in the CMB with amore » simple example where the initial state is a small perturbation away from the Bunch-Davies state. Because the state breaks some of the rotational symmetries, the angular power spectra no longer need be strictly diagonal.« less
Controversy in the allometric application of fixed- versus varying-exponent models: a statistical and mathematical perspective.

PubMed

Tang, Huadong; Hussain, Azher; Leal, Mauricio; Fluhler, Eric; Mayersohn, Michael

2011-02-01

This commentary is a reply to a recent article by Mahmood commenting on the authors' article on the use of fixed-exponent allometry in predicting human clearance. The commentary discusses eight issues that are related to criticisms made in Mahmood's article and examines the controversies (fixed-exponent vs. varying-exponent allometry) from the perspective of statistics and mathematics. The key conclusion is that any allometric method, which is to establish a power function based on a limited number of animal species and to extrapolate the resulting power function to human values (varying-exponent allometry), is infused with fundamental statistical errors. Copyright © 2010 Wiley-Liss, Inc.
78. Augmenting NMDA Receptor Signaling Enhances Working Memory and Alters Gamma Oscillations in Patients With Schizophrenia

PubMed Central

Forsyth, Jennifer; Bachman, Peter; Asarnow, Robert

2017-01-01

Abstract Background: Gamma band oscillations (30–80 Hz) are associated with numerous sensory and higher cognitive functions and are abnormal in patients with schizophrenia. Glutamate signaling at the N-methyl-D-aspartate receptor (NMDAR) is theorized to play a key role in the pathophysiology of schizophrenia and NMDAR antagonists disrupt working memory and gamma oscillations in healthy individuals. It has therefore been suggested that NMDAR dysfunction may contribute to abnormalities in gamma oscillations and working memory in schizophrenia. In the current study, we examined the effects of acutely augmenting NMDAR signaling using the NMDAR agonist, d-cycloserine (DCS), on working memory and gamma power in patients with schizophrenia. Methods: In a double-blind design, patients with schizophrenia were randomized to receive a single dose of 100 mg DCS (SZ-DCS; n = 24) or Placebo (SZ-PLC; n = 21). Patients completed a spatial n-back task involving a 0-back control condition and 1-back and 2-back working memory loads while undergoing EEG recording. Gamma power (30–80 Hz) during the 0-back condition assessed gamma power associated with basic perceptual, motor, and attentive processes. Change in gamma power for correct working memory trials relative to the 0-back condition assessed gamma power associated with working memory function. Results: Among patients who performed above chance (SZ-DCS = 17, SZ-PLC = 16), patients who received DCS showed superior working memory performance compared to patients who received Placebo. Gamma power during the 0-back control condition was similar between SZ-DCS and SZ-PLC who performed above chance. However, gamma power associated with working memory function was significantly suppressed in SZ-DCS compared to SZ-PLC, particularly over frontal right channels. In addition, whereas higher working memory gamma power over frontal right channels was associated with better working memory performance in SZ-PLC, this relationship was not evident in SZ-DCS. Conclusion: Results suggest that augmenting NMDAR signaling enhanced working memory performance and suppressed gamma activity associated with working memory function in patients with schizophrenia. Given prior reports that schizophrenia patients may utilize excessive gamma power for successful working memory performance, these findings suggest that augmenting NMDAR signaling may improve the efficiency of neural encoding for successful working memory function in schizophrenia.
Vibration analysis of FG cylindrical shells with power-law index using discrete singular convolution technique

NASA Astrophysics Data System (ADS)

Mercan, Kadir; Demir, Çiǧdem; Civalek, Ömer

2016-01-01

In the present manuscript, free vibration response of circular cylindrical shells with functionally graded material (FGM) is investigated. The method of discrete singular convolution (DSC) is used for numerical solution of the related governing equation of motion of FGM cylindrical shell. The constitutive relations are based on the Love's first approximation shell theory. The material properties are graded in the thickness direction according to a volume fraction power law indexes. Frequency values are calculated for different types of boundary conditions, material and geometric parameters. In general, close agreement between the obtained results and those of other researchers has been found.
Modeling laser brightness from cross Porro prism resonators

NASA Astrophysics Data System (ADS)

Forbes, Andrew; Burger, Liesl; Litvin, Igor Anatolievich

2006-08-01

Laser brightness is a parameter often used to compare high power laser beam delivery from various sources, and incorporates both the power contained in the particular mode, as well as the propagation of that mode through the beam quality factor, M2. In this study a cross Porro prism resonator is considered; crossed Porro prism resonators have been known for some time, but until recently have not been modeled as a complete physical optics system that allows the modal output to be determined as a function of the rotation angle of the prisms. In this paper we consider the diffraction losses as a function of the prism rotation angle relative to one another, and combine this with the propagation of the specific modes to determine the laser output brightness as a function of the prism orientation.

Forging the Basis for Developing Protein-Ligand Interaction Scoring Functions.

PubMed

Liu, Zhihai; Su, Minyi; Han, Li; Liu, Jie; Yang, Qifan; Li, Yan; Wang, Renxiao

2017-02-21

In structure-based drug design, scoring functions are widely used for fast evaluation of protein-ligand interactions. They are often applied in combination with molecular docking and de novo design methods. Since the early 1990s, a whole spectrum of protein-ligand interaction scoring functions have been developed. Regardless of their technical difference, scoring functions all need data sets combining protein-ligand complex structures and binding affinity data for parametrization and validation. However, data sets of this kind used to be rather limited in terms of size and quality. On the other hand, standard metrics for evaluating scoring function used to be ambiguous. Scoring functions are often tested in molecular docking or even virtual screening trials, which do not directly reflect the genuine quality of scoring functions. Collectively, these underlying obstacles have impeded the invention of more advanced scoring functions. In this Account, we describe our long-lasting efforts to overcome these obstacles, which involve two related projects. On the first project, we have created the PDBbind database. It is the first database that systematically annotates the protein-ligand complexes in the Protein Data Bank (PDB) with experimental binding data. This database has been updated annually since its first public release in 2004. The latest release (version 2016) provides binding data for 16 179 biomolecular complexes in PDB. Data sets provided by PDBbind have been applied to many computational and statistical studies on protein-ligand interaction and various subjects. In particular, it has become a major data resource for scoring function development. On the second project, we have established the Comparative Assessment of Scoring Functions (CASF) benchmark for scoring function evaluation. Our key idea is to decouple the "scoring" process from the "sampling" process, so scoring functions can be tested in a relatively pure context to reflect their quality. In our latest work on this track, i.e. CASF-2013, the performance of a scoring function was quantified in four aspects, including "scoring power", "ranking power", "docking power", and "screening power". All four performance tests were conducted on a test set containing 195 high-quality protein-ligand complexes selected from PDBbind. A panel of 20 standard scoring functions were tested as demonstration. Importantly, CASF is designed to be an open-access benchmark, with which scoring functions developed by different researchers can be compared on the same grounds. Indeed, it has become a popular choice for scoring function validation in recent years. Despite the considerable progress that has been made so far, the performance of today's scoring functions still does not meet people's expectations in many aspects. There is a constant demand for more advanced scoring functions. Our efforts have helped to overcome some obstacles underlying scoring function development so that the researchers in this field can move forward faster. We will continue to improve the PDBbind database and the CASF benchmark in the future to keep them as useful community resources.
Variable gas spring for matching power output from FPSE to load of refrigerant compressor

DOEpatents

Chen, Gong; Beale, William T.

1990-01-01

The power output of a free piston Stirling engine is matched to a gas compressor which it drives and its stroke amplitude is made relatively constant as a function of power by connecting a gas spring to the drive linkage from the engine to the compressor. The gas spring is connected to the compressor through a passageway in which a valve is interposed. The valve is linked to the drive linkage so it is opened when the stroke amplitude exceeds a selected limit. This allows compressed gas to enter the spring, increase its spring constant, thus opposing stroke increase and reducing the phase lead of the displacer ahead of the piston to reduce power output and match it to a reduced load power demand.
Variable gas spring for matching power output from FPSE to load of refrigerant compressor

DOEpatents

Chen, G.; Beale, W.T.

1990-04-03

The power output of a free piston Stirling engine is matched to a gas compressor which it drives and its stroke amplitude is made relatively constant as a function of power by connecting a gas spring to the drive linkage from the engine to the compressor. The gas spring is connected to the compressor through a passageway in which a valve is interposed. The valve is linked to the drive linkage so it is opened when the stroke amplitude exceeds a selected limit. This allows compressed gas to enter the spring, increase its spring constant, thus opposing stroke increase and reducing the phase lead of the displacer ahead of the piston to reduce power output and match it to a reduced load power demand. 6 figs.
Design of Compact Wilkinson Power Divider with Harmonic Suppression using T-Shaped Resonators

NASA Astrophysics Data System (ADS)

Siahkamari, Hesam; Yasoubi, Zahra; Jahanbakhshi, Maryam; Mousavi, Seyed Mohammad Hadi; Siahkamari, Payam; Nouri, Mohammad Ehsan; Azami, Sajad; Azadi, Rasoul

2018-04-01

A novel scheme of a shrunken Wilkinson power divider with harmonic suppression, using two identical resonators in the conventional Wilkinson power divider is designed. Moreover, the LC equivalent circuit and its relevant formulas are provided. To substantiate the functionality and soundness of design, a microstrip implementation of this design operating at 1 GHz with the second to eighth harmonic suppression, is developed. The proposed circuit is relatively smaller than the conventional circuit, (roughly 55% of the conventional circuit). Simulation and measurement results for the proposed scheme, which are highly consistent with one another, indicate a good insertion loss about 3.1 dB, input return loss of 20 dB and isolation of 20 dB, while sustaining high-power handling capability over the Wilkinson power divider.
Power cepstrum technique with application to model helicopter acoustic data

NASA Technical Reports Server (NTRS)

Martin, R. M.; Burley, C. L.

1986-01-01

The application of the power cepstrum to measured helicopter-rotor acoustic data is investigated. A previously applied correction to the reconstructed spectrum is shown to be incorrect. For an exact echoed signal, the amplitude of the cepstrum echo spike at the delay time is linearly related to the echo relative amplitude in the time domain. If the measured spectrum is not entirely from the source signal, the cepstrum will not yield the desired echo characteristics and a cepstral aliasing may occur because of the effective sample rate in the frequency domain. The spectral analysis bandwidth must be less than one-half the echo ripple frequency or cepstral aliasing can occur. The power cepstrum editing technique is a useful tool for removing some of the contamination because of acoustic reflections from measured rotor acoustic spectra. The cepstrum editing yields an improved estimate of the free field spectrum, but the correction process is limited by the lack of accurate knowledge of the echo transfer function. An alternate procedure, which does not require cepstral editing, is proposed which allows the complete correction of a contaminated spectrum through use of both the transfer function and delay time of the echo process.
Distinctive time-lagged resting-state networks revealed by simultaneous EEG-fMRI.

PubMed

Feige, Bernd; Spiegelhalder, Kai; Kiemen, Andrea; Bosch, Oliver G; Tebartz van Elst, Ludger; Hennig, Jürgen; Seifritz, Erich; Riemann, Dieter

2017-01-15

Functional activation as evidenced by blood oxygen level-dependent (BOLD) functional MRI changes or event-related EEG is known to closely follow patterns of stimulation or self-paced action. Any lags are compatible with axonal conduction velocities and neural integration times. The important analysis of resting state networks is generally based on the assumption that these principles also hold for spontaneous fluctuations in brain activity. Previous observations using simultaneous EEG and fMRI indicate that slower processes, with delays in the seconds range, determine at least part of the relationship between spontaneous EEG and fMRI. To assess this relationship systematically, we used deconvolution analysis of EEG-fMRI during the resting state, assessing the relationship between EEG frequency bands and fMRI BOLD across the whole brain while allowing for time lags of up to 10.5s. Cluster analysis, identifying similar BOLD time courses in relation to EEG band power peaks, showed a clear segregation of functional subsystems of the brain. Our analysis shows that fMRI BOLD increases commonly precede EEG power increases by seconds. Most zero-lag correlations, on the other hand, were negative. This indicates two main distinct neuromodulatory mechanisms: an "idling" mechanism of simultaneous electric and metabolic network anticorrelation and a "regulatory" mechanism in which metabolic network activity precedes increased EEG power by some seconds. This has to be taken into consideration in further studies which address the causal and functional relationship of metabolic and electric brain activity patterns. Copyright © 2016 Elsevier Inc. All rights reserved.
Observations of tropospheric phase scintillations at 5 GHz on vertical paths

NASA Technical Reports Server (NTRS)

Armstrong, J. W.; Sramek, R. A.

1982-01-01

The article presents observations of turbulence-induced tropospheric phase fluctuations measured at 5 GHz on the near-vertical paths relevant to many astronomical and geophysical measurements. The data are summarized as phase power spectra, structure functions, and Allan variances. Comparisons to other microwave observations indicate relatively good agreement in both the level and shape of the power spectrum of these tropospheric phase fluctuations. Implications for precision Doppler tracking of spacecraft and geodesy/radio interferometry are discussed.
DEVELOPMENTAL CHANGES IN FACT AND SOURCE RECALL: CONTRIBUTIONS FROM EXECUTIVE FUNCTION AND BRAIN ELECTRICAL ACTIVITY

PubMed Central

Rajan, Vinaya; Bell, Martha Ann

2014-01-01

Source memory involves recollecting the contextual details surrounding a memory episode. When source information is bound together, it makes a memory episodic in nature. Unfortunately, very little is known about the factors that contribute to its formation in early development. This study examined the development of source memory in middle childhood. Measures of executive function were examined as potential sources of variation in fact and source recall. Continuous electroencephalogram (EEG) measures were collected during baseline and fact and source retrieval in order to examine memory-related changes in EEG power. Six and 8-year-old children were taught 10 novel facts from two different sources and recall for fact and source information was later tested. Older children were better on fact recall, but both ages were comparable on source recall. However, source recall performance was poor at both ages, suggesting that this ability continues to develop beyond middle childhood. Regression analyses revealed that executive function uniquely predicted variance in source recall performance. Task-related increases in theta power were observed at frontal, temporal and parietal electrode sites during fact and source retrieval. This investigation contributes to our understanding of age-related differences in source memory processing in middle childhood. PMID:25459873
Gene-Based Association Analysis for Censored Traits Via Fixed Effect Functional Regressions.

PubMed

Fan, Ruzong; Wang, Yifan; Yan, Qi; Ding, Ying; Weeks, Daniel E; Lu, Zhaohui; Ren, Haobo; Cook, Richard J; Xiong, Momiao; Swaroop, Anand; Chew, Emily Y; Chen, Wei

2016-02-01

Genetic studies of survival outcomes have been proposed and conducted recently, but statistical methods for identifying genetic variants that affect disease progression are rarely developed. Motivated by our ongoing real studies, here we develop Cox proportional hazard models using functional regression (FR) to perform gene-based association analysis of survival traits while adjusting for covariates. The proposed Cox models are fixed effect models where the genetic effects of multiple genetic variants are assumed to be fixed. We introduce likelihood ratio test (LRT) statistics to test for associations between the survival traits and multiple genetic variants in a genetic region. Extensive simulation studies demonstrate that the proposed Cox RF LRT statistics have well-controlled type I error rates. To evaluate power, we compare the Cox FR LRT with the previously developed burden test (BT) in a Cox model and sequence kernel association test (SKAT), which is based on mixed effect Cox models. The Cox FR LRT statistics have higher power than or similar power as Cox SKAT LRT except when 50%/50% causal variants had negative/positive effects and all causal variants are rare. In addition, the Cox FR LRT statistics have higher power than Cox BT LRT. The models and related test statistics can be useful in the whole genome and whole exome association studies. An age-related macular degeneration dataset was analyzed as an example. © 2016 WILEY PERIODICALS, INC.
Gene-based Association Analysis for Censored Traits Via Fixed Effect Functional Regressions

PubMed Central

Fan, Ruzong; Wang, Yifan; Yan, Qi; Ding, Ying; Weeks, Daniel E.; Lu, Zhaohui; Ren, Haobo; Cook, Richard J; Xiong, Momiao; Swaroop, Anand; Chew, Emily Y.; Chen, Wei

2015-01-01

Summary Genetic studies of survival outcomes have been proposed and conducted recently, but statistical methods for identifying genetic variants that affect disease progression are rarely developed. Motivated by our ongoing real studies, we develop here Cox proportional hazard models using functional regression (FR) to perform gene-based association analysis of survival traits while adjusting for covariates. The proposed Cox models are fixed effect models where the genetic effects of multiple genetic variants are assumed to be fixed. We introduce likelihood ratio test (LRT) statistics to test for associations between the survival traits and multiple genetic variants in a genetic region. Extensive simulation studies demonstrate that the proposed Cox RF LRT statistics have well-controlled type I error rates. To evaluate power, we compare the Cox FR LRT with the previously developed burden test (BT) in a Cox model and sequence kernel association test (SKAT) which is based on mixed effect Cox models. The Cox FR LRT statistics have higher power than or similar power as Cox SKAT LRT except when 50%/50% causal variants had negative/positive effects and all causal variants are rare. In addition, the Cox FR LRT statistics have higher power than Cox BT LRT. The models and related test statistics can be useful in the whole genome and whole exome association studies. An age-related macular degeneration dataset was analyzed as an example. PMID:26782979
Using "StorAge Selection" functions and high resolution isotope data to unravel travel time distributions in headwater catchments

NASA Astrophysics Data System (ADS)

Benettin, Paolo; Soulsby, Chris; Birkel, Christian; Tetzlaff, Doerthe; Botter, Gianluca; Rinaldo, Andrea

2017-04-01

We use high resolution tracer data from the Bruntland Burn catchment (UK) to test theoretical approaches that integrate catchment-scale flow and transport processes in a unified framework centered on selective age sampling by streamflow and evapotranspiration fluxes. Hydrologic transport is here described through StorAge Selection (SAS) functions, parametrized as simple power laws. By representing the way in which catchment storage generates outflows composed by water of different ages, the main mechanism regulating the tracer composition of runoff is clearly identified. The calibrated numerical model provides simulations that convincingly reproduce complex measured signals of daily deuterium content in stream waters during wet and dry periods. The results for the catchment under consideration are consistent with other recent studies indicating a tendency for natural catchments to preferentially release younger available water. The model allows estimating transient water age and its related uncertainty, as well as the total catchment storage. This study shows that power-law SAS functions prove a powerful tool to explain catchment-scale transport processes that also has potential in less intensively monitored sites.
Characterization of the rainbow trout spleen transcriptome and identification of immune-related genes

USDA-ARS?s Scientific Manuscript database

Disease susceptibility affects production efficiency and profitability in rainbow trout aquaculture. There is limited information available regarding the functions and mechanisms of teleost immune pathways. Immunogenomics provides powerful approaches to identify disease resistance genes/gene pathway...
The qEEG Signature of Selective NMDA NR2B Negative Allosteric Modulators; A Potential Translational Biomarker for Drug Development

PubMed Central

Keavy, Deborah; Bristow, Linda J.; Sivarao, Digavalli V.; Batchelder, Margaret; King, Dalton; Thangathirupathy, Srinivasan; Macor, John E.; Weed, Michael R.

2016-01-01

The antidepressant activity of the N-methyl-D-aspartate (NMDA) receptor channel blocker, ketamine, has led to the investigation of negative allosteric modulators (NAMs) selective for the NR2B receptor subtype. The clinical development of NR2B NAMs would benefit from a translational pharmacodynamic biomarker that demonstrates brain penetration and functional inhibition of NR2B receptors in preclinical species and humans. Quantitative electroencephalography (qEEG) is a translational measure that can be used to demonstrate pharmacodynamic effects across species. NMDA receptor channel blockers, such as ketamine and phencyclidine, increase the EEG gamma power band, which has been used as a pharmacodynamic biomarker in the development of NMDA receptor antagonists. However, detailed qEEG studies with ketamine or NR2B NAMs are lacking in nonhuman primates. The aim of the present study was to determine the effects on the qEEG power spectra of the NR2B NAMs traxoprodil (CP-101,606) and BMT-108908 in nonhuman primates, and to compare them to the NMDA receptor channel blockers, ketamine and lanicemine. Cynomolgus monkeys were surgically implanted with EEG radio-telemetry transmitters, and qEEG was measured after vehicle or drug administration. The relative power for a number of frequency bands was determined. Ketamine and lanicemine increased relative gamma power, whereas the NR2B NAMs traxoprodil and BMT-108908 had no effect. Robust decreases in beta power were elicited by ketamine, traxoprodil and BMT-108908; and these agents also produced decreases in alpha power and increases in delta power at the doses tested. These results suggest that measurement of power spectra in the beta and delta bands may represent a translational pharmacodynamic biomarker to demonstrate functional effects of NR2B NAMs. The results of these studies may help guide the selection of qEEG measures that can be incorporated into early clinical evaluation of NR2B NAMs in healthy humans. PMID:27035340
Experience-dependent modulation of alpha and beta during action observation and motor imagery.

PubMed

Di Nota, Paula M; Chartrand, Julie M; Levkov, Gabriella R; Montefusco-Siegmund, Rodrigo; DeSouza, Joseph F X

2017-03-06

EEG studies investigating the neural networks that facilitate action observation (AO) and kinaesthetic motor imagery (KMI) have shown reduced, or desynchronized, power in the alpha (8-12 Hz) and beta (13-30 Hz) frequency bands relative to rest, reflecting efficient activation of task-relevant areas. Functional modulation of these networks through expertise in dance has been established using fMRI, with greater activation among experts during AO. While there is evidence for experience-dependent plasticity of alpha power during AO of dance, the influence of familiarity on beta power during AO, and alpha and beta activity during KMI, remain unclear. The purpose of the present study was to measure the impact of familiarity on confidence ratings and EEG activity during (1) AO of a brief ballet sequence, (2) KMI of this same sequence, and (3) KMI of non-dance movements among ballet dancers, dancers from other genres, and non-dancers. Ballet dancers highly familiar with the genre of the experimental stimulus demonstrated higher individual alpha peak frequency (iAPF), greater alpha desynchronization, and greater task-related beta power during AO, as well as faster iAPF during KMI of non-dance movements. While no between-group differences in alpha or beta power were observed during KMI of dance or non-dance movements, all participants showed significant desynchronization relative to baseline, and further desynchronization during dance KMI relative to non-dance KMI indicative of greater cognitive load. These findings confirm and extend evidence for experience-dependent plasticity of alpha and beta activity during AO of dance and KMI. We also provide novel evidence for modulation of iAPF that is faster when tuned to the specific motor repertoire of the observer. By considering the multiple functional roles of these frequency bands during the same task (AO), we have disentangled the compounded contribution of familiarity and expertise to alpha desynchronization for mediating task engagement among familiar ballet dancers and reflecting task difficulty among unfamiliar non-dance subjects, respectively. That KMI of a complex dance sequence relative to everyday, non-dance movements recruits greater cognitive resources suggests it may be a more powerful tool in driving neural plasticity of action networks, especially among the elderly and those with movement disorders.
Specification of absorbed-sound power in the ear canal: Application to suppression of stimulus frequency otoacoustic emissions

PubMed Central

Keefe, Douglas H.; Schairer, Kim S.

2011-01-01

An insert ear-canal probe including sound source and microphone can deliver a calibrated sound power level to the ear. The aural power absorbed is proportional to the product of mean-squared forward pressure, ear-canal area, and absorbance, in which the sound field is represented using forward (reverse) waves traveling toward (away from) the eardrum. Forward pressure is composed of incident pressure and its multiple internal reflections between eardrum and probe. Based on a database of measurements in normal-hearing adults from 0.22 to 8 kHz, the transfer-function level of forward relative to incident pressure is boosted below 0.7 kHz and within 4 dB above. The level of forward relative to total pressure is maximal close to 4 kHz with wide variability across ears. A spectrally flat incident-pressure level across frequency produces a nearly flat absorbed power level, in contrast to 19 dB changes in pressure level. Calibrating an ear-canal sound source based on absorbed power may be useful in audiological and research applications. Specifying the tip-to-tail level difference of the suppression tuning curve of stimulus frequency otoacoustic emissions in terms of absorbed power reveals increased cochlear gain at 8 kHz relative to the level difference measured using total pressure. PMID:21361437
Removing an intersubject variance component in a general linear model improves multiway factoring of event-related spectral perturbations in group EEG studies.

PubMed

Spence, Jeffrey S; Brier, Matthew R; Hart, John; Ferree, Thomas C

2013-03-01

Linear statistical models are used very effectively to assess task-related differences in EEG power spectral analyses. Mixed models, in particular, accommodate more than one variance component in a multisubject study, where many trials of each condition of interest are measured on each subject. Generally, intra- and intersubject variances are both important to determine correct standard errors for inference on functions of model parameters, but it is often assumed that intersubject variance is the most important consideration in a group study. In this article, we show that, under common assumptions, estimates of some functions of model parameters, including estimates of task-related differences, are properly tested relative to the intrasubject variance component only. A substantial gain in statistical power can arise from the proper separation of variance components when there is more than one source of variability. We first develop this result analytically, then show how it benefits a multiway factoring of spectral, spatial, and temporal components from EEG data acquired in a group of healthy subjects performing a well-studied response inhibition task. Copyright © 2011 Wiley Periodicals, Inc.
Influence of the spectral power distribution of a LED on the illuminance responsivity of a photometer

NASA Astrophysics Data System (ADS)

Sametoglu, Ferhat

2008-09-01

The measurement accuracy in the photometric quantities measured through photometer head is determined by the value of the spectral mismatch correction factor ( c( St, Ss)), which is defined as a function of spectral power distribution of light sources, besides illuminance responsivity of the photometer head used. This factor is more important when photometric quantities of the light-emitting diode (LED) style optical sources, which radiate within relatively narrow spectral bands as compared with that of other optical sources, are being measured. Variations of the illuminance responsivities of various V( λ)-adopted photometer heads are discussed. High-power-colored LEDs, manufactured by Lumileds Lighting Co., were used as light sources and their relative spectral power distributions (RSPDs) were measured using a spectrometer-based optical setup. Dependences of the c( St, Ss) factors of three types of photometer heads ( f1'=1.4%, f1'=0.8% and f1'=0.5%) with wavelength and influences of the factors on the illuminance responsivities of photometer heads are presented.
Changes of Functional and Directed Resting-State Connectivity Are Associated with Neuronal Oscillations, ApoE Genotype and Amyloid Deposition in Mild Cognitive Impairment

PubMed Central

Michels, Lars; Muthuraman, Muthuraman; Anwar, Abdul R.; Kollias, Spyros; Leh, Sandra E.; Riese, Florian; Unschuld, Paul G.; Siniatchkin, Michael; Gietl, Anton F.; Hock, Christoph

2017-01-01

The assessment of effects associated with cognitive impairment using electroencephalography (EEG) power mapping allows the visualization of frequency-band specific local changes in oscillatory activity. In contrast, measures of coherence and dynamic source synchronization allow for the study of functional and effective connectivity, respectively. Yet, these measures have rarely been assessed in parallel in the context of mild cognitive impairment (MCI) and furthermore it has not been examined if they are related to risk factors of Alzheimer’s disease (AD) such as amyloid deposition and apolipoprotein ε4 (ApoE) allele occurrence. Here, we investigated functional and directed connectivities with Renormalized Partial Directed Coherence (RPDC) in 17 healthy controls (HC) and 17 participants with MCI. Participants underwent ApoE-genotyping and Pittsburgh compound B positron emission tomography (PiB-PET) to assess amyloid deposition. We observed lower spectral source power in MCI in the alpha and beta bands. Coherence was stronger in HC than MCI across different neuronal sources in the delta, theta, alpha, beta and gamma bands. The directed coherence analysis indicated lower information flow between fronto-temporal (including the hippocampus) sources and unidirectional connectivity in MCI. In MCI, alpha and beta RPDC showed an inverse correlation to age and gender; global amyloid deposition was inversely correlated to alpha coherence, RPDC and beta and gamma coherence. Furthermore, the ApoE status was negatively correlated to alpha coherence and RPDC, beta RPDC and gamma coherence. A classification analysis of cognitive state revealed the highest accuracy using EEG power, coherence and RPDC as input. For this small but statistically robust (Bayesian power analyses) sample, our results suggest that resting EEG related functional and directed connectivities are sensitive to the cognitive state and are linked to ApoE and amyloid burden. PMID:29081745
Space Tug avionics definition study. Volume 1: Executive summary

NASA Technical Reports Server (NTRS)

1975-01-01

A top down approach was used to identify, compile, and develop avionics functional requirements for all flight and ground operational phases. Such requirements as safety mission critical functions and criteria, minimum redundancy levels, software memory sizing, power for tug and payload, data transfer between payload, tug, shuttle, and ground were established. Those functional requirements that related to avionics support of a particular function were compiled together under that support function heading. This unique approach provided both organizational efficiency and traceability back to the applicable operational phase and event. Each functional requirement was then allocated to the appropriate subsystems and its particular characteristics were quantified.
Insight into RF power requirements and B1 field homogeneity for human MRI via rigorous FDTD approach.

PubMed

Ibrahim, Tamer S; Tang, Lin

2007-06-01

To study the dependence of radiofrequency (RF) power deposition on B(0) field strength for different loads and excitation mechanisms. Studies were performed utilizing a finite difference time domain (FDTD) model that treats the transmit array and the load as a single system. Since it was possible to achieve homogenous excitations across the human head model by varying the amplitudes/phases of the voltages driving the transmit array, studies of the RF power/B(0) field strength (frequency) dependence were achievable under well-defined/fixed/homogenous RF excitation. Analysis illustrating the regime in which the RF power is dependent on the square of the operating frequency is presented. Detailed studies focusing on the RF power requirements as a function of number of excitation ports, driving mechanism, and orientations/positioning within the load are presented. With variable phase/amplitude excitation, as a function of frequency, the peak-then-decrease relation observed in the upper axial slices of brain with quadrature excitation becomes more evident in the lower slices as well. Additionally, homogeneity optimization targeted at minimizing the ratio of maximum/minimum B(1) (+) field intensity within the region of interest, typically results in increased RF power requirements (standard deviation was not considered in this study). Increasing the number of excitation ports, however, can result in significant RF power reduction. (c) 2007 Wiley-Liss, Inc.

Research study on multi-KW-DC distribution system

NASA Technical Reports Server (NTRS)

Berkery, E. A.; Krausz, A.

1975-01-01

A detailed definition of the HVDC test facility and the equipment required to implement the test program are provided. The basic elements of the test facility are illustrated, and consist of: the power source, conventional and digital supervision and control equipment, power distribution harness and simulated loads. The regulated dc power supplies provide steady-state power up to 36 KW at 120 VDC. Power for simulated line faults will be obtained from two banks of 90 ampere-hour lead-acid batteries. The relative merits of conventional and multiplexed power control will be demonstrated by the Supervision and Monitor Unit (SMU) and the Automatically Controlled Electrical Systems (ACES) hardware. The distribution harness is supported by a metal duct which is bonded to all component structures and functions as the system ground plane. The load banks contain passive resistance and reactance loads, solid state power controllers and active pulse width modulated loads. The HVDC test facility is designed to simulate a power distribution system for large aerospace vehicles.
28 CFR 0.65 - General functions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... and operations of nuclear power plants. (g) Civil and criminal suits and matters relating to the... Judicial Administration DEPARTMENT OF JUSTICE ORGANIZATION OF THE DEPARTMENT OF JUSTICE Environment and... conducted, handled, or supervised by the Assistant Attorney General in charge of the Environment and Natural...
Energy loss analysis of an integrated space power distribution system

NASA Technical Reports Server (NTRS)

Kankam, M. D.; Ribeiro, P. F.

1992-01-01

The results of studies related to conceptual topologies of an integrated utility-like space power system are described. The system topologies are comparatively analyzed by considering their transmission energy losses as functions of mainly distribution voltage level and load composition. The analysis is expedited by use of a Distribution System Analysis and Simulation (DSAS) software. This recently developed computer program by the Electric Power Research Institute (EPRI) uses improved load models to solve the power flow within the system. However, present shortcomings of the software with regard to space applications, and incompletely defined characteristics of a space power system make the results applicable to only the fundamental trends of energy losses of the topologies studied. Accountability, such as included, for the effects of the various parameters on the system performance can constitute part of a planning tool for a space power distribution system.
Assessing the performance of self-consistent hybrid functional for band gap calculation in oxide semiconductors

NASA Astrophysics Data System (ADS)

He, Jiangang; Franchini, Cesare

2017-11-01

In this paper we assess the predictive power of the self-consistent hybrid functional scPBE0 in calculating the band gap of oxide semiconductors. The computational procedure is based on the self-consistent evaluation of the mixing parameter α by means of an iterative calculation of the static dielectric constant using the perturbation expansion after discretization method and making use of the relation \
Cardiorespiratory and neuromuscular deconditioning in fatigued and non-fatigued breast cancer survivors.

PubMed

Neil, Sarah E; Klika, Riggs J; Garland, S Jayne; McKenzie, Donald C; Campbell, Kristin L

2013-03-01

Fatigue is one of the most commonly reported side effects during treatment for breast cancer and can persist following treatment completion. Cancer-related fatigue after treatment is multifactorial in nature, and one hypothesized mechanism is cardiorespiratory and neuromuscular deconditioning. The purpose of this study was to compare cardiorespiratory and neuromuscular function in breast cancer survivors who had completed treatment and met the specified criteria for cancer-related fatigue and a control group of breast cancer survivors without fatigue. Participants in the fatigue (n = 16) and control group (n = 11) performed a maximal exercise test on a cycle ergometer for determination of peak power, power at lactate threshold, and VO(2) peak. Neuromuscular fatigue was induced with a sustained submaximal contraction of the right quadriceps. Central fatigue (failure of voluntary activation) was evaluated using twitch interpolation, and peripheral fatigue was measured with an electrically evoked twitch. Power at lactate threshold was lower in the fatigue group (p = 0.05). There were no differences between groups for power at lactate threshold as percentage of peak power (p = 0.10) or absolute or relative VO(2) peak (p = 0.08 and 0.33, respectively). When adjusted for age, the fatigue group had a lower power at lactate threshold (p = 0.02) and absolute VO(2) peak (p = 0.03). There were no differences between groups in change in any neuromuscular parameters after the muscle-fatiguing protocol. Findings support the hypothesis that cardiorespiratory deconditioning may play a role in the development and persistence of cancer-related fatigue following treatment. Future research into the use of exercise training to reduce cardiorespiratory deconditioning as a treatment for cancer-related fatigue is warranted to confirm these preliminary findings.
First quantitative measurements of charged-particle stopping and its dependence on electron temperature and density in Inertial-Confinement-Fusion plasmas

NASA Astrophysics Data System (ADS)

Frenje, J.; Li, C. K.; Séguin, F.; Zylstra, A.; Rinderknecht, H.; Petrasso, R.; Delettrez, J.; Glebov, V.; Sangster, T.

2013-10-01

We report on the first quantitative measurements of charged-particle stopping in Inertial-Confinement-Fusion (ICF) plasmas at various conditions. In these experiments, four charged fusion products from the DD and D3He reactions in D3He gas-filled filled implosions were used to determine the stopping power of ICF plasmas at electron temperatures (Te) , ion temperatures (Ti) , and areal densities (ρR) in the range of 0.6-4.0 keV, 3-14 keV and 2-10 mg/cm2, respectively. The resulting data, in the form of measured energy downshift of the charged fusion products, clearly indicate that the stopping-power function depends strongly on Te. It was also observed that the stopping-power function change in characteristics for higher-density implosions in which ions and electrons equilibrate faster, resulting in higher Te relative to Ti and higher ρR s. These results will be modelled by Landau-Spitzer theory and contrasted to different stopping-power models. This work was partially supported by the US DOE, NLUF, LLE, and GA.
Testosterone dose-response relationships in hysterectomized women with or without oophorectomy: effects on sexual function, body composition, muscle performance and physical function in a randomized trial.

PubMed

Huang, Grace; Basaria, Shehzad; Travison, Thomas G; Ho, Matthew H; Davda, Maithili; Mazer, Norman A; Miciek, Renee; Knapp, Philip E; Zhang, Anqi; Collins, Lauren; Ursino, Monica; Appleman, Erica; Dzekov, Connie; Stroh, Helene; Ouellette, Miranda; Rundell, Tyler; Baby, Merilyn; Bhatia, Narender N; Khorram, Omid; Friedman, Theodore; Storer, Thomas W; Bhasin, Shalender

2014-06-01

This study aims to determine the dose-dependent effects of testosterone on sexual function, body composition, muscle performance, and physical function in hysterectomized women with or without oophorectomy. Seventy-one postmenopausal women who previously underwent hysterectomy with or without oophorectomy and had total testosterone levels less than 31 ng/dL or free testosterone levels less than 3.5 pg/mL received a standardized transdermal estradiol regimen during the 12-week run-in period and were randomized to receive weekly intramuscular injections of placebo or 3, 6.25, 12.5, or 25 mg of testosterone enanthate for 24 weeks. Total and free testosterone levels were measured by liquid chromatography-tandem mass spectrometry and equilibrium dialysis, respectively. The primary outcome was change in sexual function measured by the Brief Index of Sexual Functioning for Women. Secondary outcomes included changes in sexual activity, sexual distress, Derogatis Interview for Sexual Functioning, lean body mass, fat mass, muscle strength and power, and physical function. Seventy-one women were randomized; five groups were similar at baseline. Sixty-two women with analyzable data for the primary outcome were included in the final analysis. The mean on-treatment total testosterone concentrations were 19, 78, 102, 128, and 210 ng/dL in the placebo, 3-mg, 6.25-mg, 12.5-mg, and 25-mg groups, respectively. Changes in composite Brief Index of Sexual Functioning for Women scores, thoughts/desire, arousal, frequency of sexual activity, lean body mass, chest-press power, and loaded stair-climb power were significantly related to increases in free testosterone concentrations; compared with placebo, changes were significantly greater in women assigned to the 25-mg group, but not in women in the lower-dose groups. Sexual activity increased by 2.7 encounters per week in the 25-mg group. The frequency of androgenic adverse events was low. Testosterone administration in hysterectomized women with or without oophorectomy for 24 weeks was associated with dose and concentration-dependent gains in several domains of sexual function, lean body mass, chest-press power, and loaded stair-climb power. Long-term trials are needed to weigh improvements in these outcomes against potential long-term adverse effects.
Epaxial muscle fiber architecture favors enhanced excursion and power in the leaper Galago senegalensis

PubMed Central

Huq, Emranul; Wall, Christine E; Taylor, Andrea B

2015-01-01

Galago senegalensis is a habitual arboreal leaper that engages in rapid spinal extension during push-off. Large muscle excursions and high contraction velocities are important components of leaping, and experimental studies indicate that during leaping by G. senegalensis, peak power is facilitated by elastic storage of energy. To date, however, little is known about the functional relationship between epaxial muscle fiber architecture and locomotion in leaping primates. Here, fiber architecture of select epaxial muscles is compared between G. senegalensis (n = 4) and the slow arboreal quadruped, Nycticebus coucang (n = 4). The hypothesis is tested that G. senegalensis exhibits architectural features of the epaxial muscles that facilitate rapid and powerful spinal extension during the take-off phase of leaping. As predicted, G. senegalensis epaxial muscles have relatively longer, less pinnate fibers and higher ratios of tendon length-to-fiber length, indicating the capacity for generating relatively larger muscle excursions, higher whole-muscle contraction velocities, and a greater capacity for elastic energy storage. Thus, the relatively longer fibers and higher tendon length-to-fiber length ratios can be functionally linked to leaping performance in G. senegalensis. It is further predicted that G. senegalensis epaxial muscles have relatively smaller physiological cross-sectional areas (PCSAs) as a consequence of an architectural trade-off between fiber length (excursion) and PCSA (force). Contrary to this prediction, there are no species differences in relative PCSAs, but the smaller-bodied G. senegalensis trends towards relatively larger epaxial muscle mass. These findings suggest that relative increase in muscle mass in G. senegalensis is largely attributable to longer fibers. The relative increase in erector spinae muscle mass may facilitate sagittal flexibility during leaping. The similarity between species in relative PCSAs provides empirical support for previous work linking osteological features of the vertebral column in lorisids with axial stability and reduced muscular effort associated with slow, deliberate movements during anti-pronograde locomotion. PMID:26184388
Repeated Evolution of Power-Amplified Predatory Strikes in Trap-Jaw Spiders.

PubMed

Wood, Hannah M; Parkinson, Dilworth Y; Griswold, Charles E; Gillespie, Rosemary G; Elias, Damian O

2016-04-25

Small animals possess intriguing morphological and behavioral traits that allow them to capture prey, including innovative structural mechanisms that produce ballistic movements by amplifying power [1-6]. Power amplification occurs when an organism produces a relatively high power output by releasing slowly stored energy almost instantaneously, resulting in movements that surpass the maximal power output of muscles [7]. For example, trap-jaw, power-amplified mechanisms have been described for several ant genera [5, 8], which have evolved some of the fastest known movements in the animal kingdom [6]. However, power-amplified predatory strikes were not previously known in one of the largest animal classes, the arachnids. Mecysmaucheniidae spiders, which occur only in New Zealand and southern South America, are tiny, cryptic, ground-dwelling spiders that rely on hunting rather than web-building to capture prey [9]. Analysis of high-speed video revealed that power-amplified mechanisms occur in some mecysmaucheniid species, with the fastest species being two orders of magnitude faster than the slowest species. Molecular phylogenetic analysis revealed that power-amplified cheliceral strikes have evolved four times independently within the family. Furthermore, we identified morphological innovations that directly relate to cheliceral function: a highly modified carapace in which the cheliceral muscles are oriented horizontally; modification of a cheliceral sclerite to have muscle attachments; and, in the power-amplified species, a thicker clypeus and clypeal apodemes. These structural innovations may have set the stage for the parallel evolution of ballistic predatory strikes. Copyright © 2016 Elsevier Ltd. All rights reserved.
Computer Code for Interpreting 13C NMR Relaxation Measurements with Specific Models of Molecular Motion: The Rigid Isotropic and Symmetric Top Rotor Models and the Flexible Symmetric Top Rotor Model

DTIC Science & Technology

2017-01-01

unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT: Carbon-13 nuclear magnetic resonance (13C NMR) spectroscopy is a powerful technique for...FLEXIBLE SYMMETRIC TOP ROTOR MODEL 1. INTRODUCTION Nuclear magnetic resonance (NMR) spectroscopy is a tremendously powerful technique for...application of NMR spectroscopy concerns the property of molecular motion, which is related to many physical, and even biological, functions of molecules in
Preliminary chaotic model of snapover on high voltage solar cells

NASA Technical Reports Server (NTRS)

Mackey, Willie R.

1995-01-01

High voltage power systems in space will interact with the space plasma in a variety of ways. One of these, snapover, is characterized by sudden enlargement of the current collection area across normally insulating surfaces generating enhanced electron current collection. Power drain on solar array power systems results from this enhanced current collection. Optical observations of the snapover phenomena in the laboratory indicates a functional relation between glow area and bia potential as a consequence of the fold/cusp bifurcation in chaos theory. Successful characterizations of snapover as a chaotic phenomena may provide a means of snapover prevention and control through chaotic synchronization.
Determining the parameters of Weibull function to estimate the wind power potential in conditions of limited source meteorological data

NASA Astrophysics Data System (ADS)

Fetisova, Yu. A.; Ermolenko, B. V.; Ermolenko, G. V.; Kiseleva, S. V.

2017-04-01

We studied the information basis for the assessment of wind power potential on the territory of Russia. We described the methodology to determine the parameters of the Weibull function, which reflects the density of distribution of probabilities of wind flow speeds at a defined basic height above the surface of the earth using the available data on the average speed at this height and its repetition by gradations. The application of the least square method for determining these parameters, unlike the use of graphical methods, allows performing a statistical assessment of the results of approximation of empirical histograms by the Weibull formula. On the basis of the computer-aided analysis of the statistical data, it was shown that, at a fixed point where the wind speed changes at different heights, the range of parameter variation of the Weibull distribution curve is relatively small, the sensitivity of the function to parameter changes is quite low, and the influence of changes on the shape of speed distribution curves is negligible. Taking this into consideration, we proposed and mathematically verified the methodology of determining the speed parameters of the Weibull function at other heights using the parameter computations for this function at a basic height, which is known or defined by the average speed of wind flow, or the roughness coefficient of the geological substrate. We gave examples of practical application of the suggested methodology in the development of the Atlas of Renewable Energy Resources in Russia in conditions of deficiency of source meteorological data. The proposed methodology, to some extent, may solve the problem related to the lack of information on the vertical profile of repeatability of the wind flow speeds in the presence of a wide assortment of wind turbines with different ranges of wind-wheel axis heights and various performance characteristics in the global market; as a result, this methodology can become a powerful tool for effective selection of equipment in the process of designing a power supply system in a certain location.
Dissecting the genetics of the human transcriptome identifies novel trait-related trans-eQTLs and corroborates the regulatory relevance of non-protein coding loci†.

PubMed

Kirsten, Holger; Al-Hasani, Hoor; Holdt, Lesca; Gross, Arnd; Beutner, Frank; Krohn, Knut; Horn, Katrin; Ahnert, Peter; Burkhardt, Ralph; Reiche, Kristin; Hackermüller, Jörg; Löffler, Markus; Teupser, Daniel; Thiery, Joachim; Scholz, Markus

2015-08-15

Genetics of gene expression (eQTLs or expression QTLs) has proved an indispensable tool for understanding biological pathways and pathomechanisms of trait-associated SNPs. However, power of most genome-wide eQTL studies is still limited. We performed a large eQTL study in peripheral blood mononuclear cells of 2112 individuals increasing the power to detect trans-effects genome-wide. Going beyond univariate SNP-transcript associations, we analyse relations of eQTLs to biological pathways, polygenetic effects of expression regulation, trans-clusters and enrichment of co-localized functional elements. We found eQTLs for about 85% of analysed genes, and 18% of genes were trans-regulated. Local eSNPs were enriched up to a distance of 5 Mb to the transcript challenging typically implemented ranges of cis-regulations. Pathway enrichment within regulated genes of GWAS-related eSNPs supported functional relevance of identified eQTLs. We demonstrate that nearest genes of GWAS-SNPs might frequently be misleading functional candidates. We identified novel trans-clusters of potential functional relevance for GWAS-SNPs of several phenotypes including obesity-related traits, HDL-cholesterol levels and haematological phenotypes. We used chromatin immunoprecipitation data for demonstrating biological effects. Yet, we show for strongly heritable transcripts that still little trans-chromosomal heritability is explained by all identified trans-eSNPs; however, our data suggest that most cis-heritability of these transcripts seems explained. Dissection of co-localized functional elements indicated a prominent role of SNPs in loci of pseudogenes and non-coding RNAs for the regulation of coding genes. In summary, our study substantially increases the catalogue of human eQTLs and improves our understanding of the complex genetic regulation of gene expression, pathways and disease-related processes. © The Author 2015. Published by Oxford University Press.
Epileptic seizures as condensed sleep: an analysis of network dynamics from electroencephalogram signals.

PubMed

Gast, Heidemarie; Müller, Markus; Rummel, Christian; Roth, Corinne; Mathis, Johannes; Schindler, Kaspar; Bassetti, Claudio L

2014-06-01

Both deepening sleep and evolving epileptic seizures are associated with increasing slow-wave activity. Larger-scale functional networks derived from electroencephalogram indicate that in both transitions dramatic changes of communication between brain areas occur. During seizures these changes seem to be 'condensed', because they evolve more rapidly than during deepening sleep. Here we set out to assess quantitatively functional network dynamics derived from electroencephalogram signals during seizures and normal sleep. Functional networks were derived from electroencephalogram signals from wakefulness, light and deep sleep of 12 volunteers, and from pre-seizure, seizure and post-seizure time periods of 10 patients suffering from focal onset pharmaco-resistant epilepsy. Nodes of the functional network represented electrical signals recorded by single electrodes and were linked if there was non-random cross-correlation between the two corresponding electroencephalogram signals. Network dynamics were then characterized by the evolution of global efficiency, which measures ease of information transmission. Global efficiency was compared with relative delta power. Global efficiency significantly decreased both between light and deep sleep, and between pre-seizure, seizure and post-seizure time periods. The decrease of global efficiency was due to a loss of functional links. While global efficiency decreased significantly, relative delta power increased except between the time periods wakefulness and light sleep, and pre-seizure and seizure. Our results demonstrate that both epileptic seizures and deepening sleep are characterized by dramatic fragmentation of larger-scale functional networks, and further support the similarities between sleep and seizures. © 2013 European Sleep Research Society.
Discovery of functional elements in 12 Drosophila genomes using evolutionary signatures

PubMed Central

Stark, Alexander; Lin, Michael F.; Kheradpour, Pouya; Pedersen, Jakob S.; Parts, Leopold; Carlson, Joseph W.; Crosby, Madeline A.; Rasmussen, Matthew D.; Roy, Sushmita; Deoras, Ameya N.; Ruby, J. Graham; Brennecke, Julius; Hodges, Emily; Hinrichs, Angie S.; Caspi, Anat; Paten, Benedict; Park, Seung-Won; Han, Mira V.; Maeder, Morgan L.; Polansky, Benjamin J.; Robson, Bryanne E.; Aerts, Stein; van Helden, Jacques; Hassan, Bassem; Gilbert, Donald G.; Eastman, Deborah A.; Rice, Michael; Weir, Michael; Hahn, Matthew W.; Park, Yongkyu; Dewey, Colin N.; Pachter, Lior; Kent, W. James; Haussler, David; Lai, Eric C.; Bartel, David P.; Hannon, Gregory J.; Kaufman, Thomas C.; Eisen, Michael B.; Clark, Andrew G.; Smith, Douglas; Celniker, Susan E.; Gelbart, William M.; Kellis, Manolis

2008-01-01

Sequencing of multiple related species followed by comparative genomics analysis constitutes a powerful approach for the systematic understanding of any genome. Here, we use the genomes of 12 Drosophila species for the de novo discovery of functional elements in the fly. Each type of functional element shows characteristic patterns of change, or ‘evolutionary signatures’, dictated by its precise selective constraints. Such signatures enable recognition of new protein-coding genes and exons, spurious and incorrect gene annotations, and numerous unusual gene structures, including abundant stop-codon readthrough. Similarly, we predict non-protein-coding RNA genes and structures, and new microRNA (miRNA) genes. We provide evidence of miRNA processing and functionality from both hairpin arms and both DNA strands. We identify several classes of pre- and post-transcriptional regulatory motifs, and predict individual motif instances with high confidence. We also study how discovery power scales with the divergence and number of species compared, and we provide general guidelines for comparative studies. PMID:17994088
Effects of dust size distribution on dust acoustic waves in two-dimensional unmagnetized dusty plasma

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

He Guangjun; Duan Wenshan; Tian Duoxiang

2008-04-15

For unmagnetized dusty plasma with many different dust grain species containing both hot isothermal electrons and ions, both the linear dispersion relation and the Kadomtsev-Petviashvili equation for small, but finite amplitude dust acoustic waves are obtained. The linear dispersion relation is investigated numerically. Furthermore, the variations of amplitude, width, and propagation velocity of the nonlinear solitary wave with an arbitrary dust size distribution function are studied as well. Moreover, both the power law distribution and the Gaussian distribution are approximately simulated by using appropriate arbitrary dust size distribution functions.
The relationship between movement speed and duration during soccer matches.

PubMed

Roecker, Kai; Mahler, Hubert; Heyde, Christian; Röll, Mareike; Gollhofer, Albert

2017-01-01

The relationship between the time duration of movement (t(dur)) and related maximum possible power output has been studied and modeled under many conditions. Inspired by the so-called power profiles known for discontinuous endurance sports like cycling, and the critical power concept of Monod and Scherrer, the aim of this study was to evaluate the numerical characteristics of the function between maximum horizontal movement velocity (HSpeed) and t(dur) in soccer. To evaluate this relationship, GPS data from 38 healthy soccer players and 82 game participations (≥30 min active playtime) were used to select maximum HSpeed for 21 distinct t(dur) values (between 0.3 s and 2,700 s) based on moving medians with an incremental t(dur) window-size. As a result, the relationship between HSpeed and Log(t(dur)) appeared reproducibly as a sigmoidal decay function, and could be fitted to a five-parameter equation with upper and lower asymptotes, and an inflection point, power and decrease rate. Thus, the first three parameters described individual characteristics if evaluated using mixed-model analysis. This study shows for the first time the general numerical relationship between t(dur) and HSpeed in soccer games. In contrast to former descriptions that have evaluated speed against power, HSpeed against t(dur) always yields a sigmoidal shape with a new upper asymptote. The evaluated curve fit potentially describes the maximum moving speed of individual players during the game, and allows for concise interpretations of the functional state of team sports athletes.
The relationship between movement speed and duration during soccer matches

PubMed Central

Mahler, Hubert; Heyde, Christian; Röll, Mareike; Gollhofer, Albert

2017-01-01

The relationship between the time duration of movement (t(dur)) and related maximum possible power output has been studied and modeled under many conditions. Inspired by the so-called power profiles known for discontinuous endurance sports like cycling, and the critical power concept of Monod and Scherrer, the aim of this study was to evaluate the numerical characteristics of the function between maximum horizontal movement velocity (HSpeed) and t(dur) in soccer. To evaluate this relationship, GPS data from 38 healthy soccer players and 82 game participations (≥30 min active playtime) were used to select maximum HSpeed for 21 distinct t(dur) values (between 0.3 s and 2,700 s) based on moving medians with an incremental t(dur) window-size. As a result, the relationship between HSpeed and Log(t(dur)) appeared reproducibly as a sigmoidal decay function, and could be fitted to a five-parameter equation with upper and lower asymptotes, and an inflection point, power and decrease rate. Thus, the first three parameters described individual characteristics if evaluated using mixed-model analysis. This study shows for the first time the general numerical relationship between t(dur) and HSpeed in soccer games. In contrast to former descriptions that have evaluated speed against power, HSpeed against t(dur) always yields a sigmoidal shape with a new upper asymptote. The evaluated curve fit potentially describes the maximum moving speed of individual players during the game, and allows for concise interpretations of the functional state of team sports athletes. PMID:28742832
ISS and Space Environment Interactions in Event of Plasma Contactor Failure

NASA Technical Reports Server (NTRS)

Carruth, M. R., Jr.; Munafo, Paul M. (Technical Monitor)

2000-01-01

The International Space Station (ISS), illustrated in Figure 1, will be the largest, highest power spacecraft placed in orbit. Because of this the design of the electrical power system diverged markedly from previous systems. The solar arrays will operate at 160 V and the power distribution voltage will be 120 V. The structure is grounded to the negative side of the solar arrays so under the right circumstances it is possible to drive the ISS potential very negative. A plasma contactor has been added to the ISS to provide control of the ISS structure potential relative to the ambient plasma. The ISS requirement is that the ISS structure not be greater than 40 V positive or negative of local plasma. What are the ramifications of operating large structures with such high voltage power systems? The application of a plasma contactor on ISS controls the potential between the structure and the local plasma, preventing degrading effects. It is conceivable that there can be situations where the plasma contactor might be non-functional. This might be due to lack of power, the need to turn it off during some of the build-up sequences, the loss of functionality for both plasma contactors before a replacement can be installed, and similar circumstances. A study was undertaken to understand how important it is to have the contactor functioning and how long it might be off before unacceptable degradation to ISS could occur.
Linking functional and relational service quality to customer satisfaction and loyalty: differences between men and women.

PubMed

Sánchez-Hernández, Rosa M; Martínez-Tur, Vicente; Peiró, José M; Moliner, Carolina

2010-04-01

This study assessed differences between men and women in the association of perceptions of service quality with customer evaluations. Functional (efficiency with which the service is delivered) and relational (customers' emotional benefits, beyond the core performance, related to the social interaction of customers with employees) dimensions of service quality were measured as well as customer satisfaction and loyalty. The sample of 277 customers (191 men, 86 women), surveyed in 29 Mexican hotels, had a mean age of 38.1 yr. (SD=9.7) for men and 34.5 yr. (SD=11.0) for women. To be eligible for survey, customers had to have spent at least one night in the hotel in question. Analysis indicated that the women and men differed in the association of functional and relational dimensions of service quality with their satisfaction and loyalty. Functional service quality was higher for the men than the women, while relational service quality showed greater predictive power for women than for men, although these accounted for only 4% of the customers' satisfaction variance and 6% of the loyalty variance.

The power laws of nanoscale forces in ambient conditions

NASA Astrophysics Data System (ADS)

Chiesa, Matteo; Santos, Sergio; Lai, Chia-Yun

Power laws are ubiquitous in the physical sciences and indispensable to qualitatively and quantitatively describe physical phenomena. A nanoscale force law that accurately describes the phenomena observed in ambient conditions at several nm or fractions of a nm above a surface however is still lacking. Here we report a power law derived from experimental data and describing the interaction between an atomic force microscope AFM tip modelled as a sphere and a surface in ambient conditions. By employing a graphite surface as a model system the resulting effective power is found to be a function of the tip radius and the distance. The data suggest a nano to mesoscale transition in the power law that results in relative agreement with the distance-dependencies predicted by the Hamaker and Lifshitz theories for van der Waals forces for the larger tip radii only
Modelling altered revenue function based on varying power consumption distribution and electricity tariff charge using data analytics framework

NASA Astrophysics Data System (ADS)

Zainudin, W. N. R. A.; Ramli, N. A.

2017-09-01

In 2010, Energy Commission (EC) had introduced Incentive Based Regulation (IBR) to ensure sustainable Malaysian Electricity Supply Industry (MESI), promotes transparent and fair returns, encourage maximum efficiency and maintains policy driven end user tariff. To cater such revolutionary transformation, a sophisticated system to generate policy driven electricity tariff structure is in great need. Hence, this study presents a data analytics framework that generates altered revenue function based on varying power consumption distribution and tariff charge function. For the purpose of this study, the power consumption distribution is being proxy using proportion of household consumption and electricity consumed in KwH and the tariff charge function is being proxy using three-tiered increasing block tariff (IBT). The altered revenue function is useful to give an indication on whether any changes in the power consumption distribution and tariff charges will give positive or negative impact to the economy. The methodology used for this framework begins by defining the revenue to be a function of power consumption distribution and tariff charge function. Then, the proportion of household consumption and tariff charge function is derived within certain interval of electricity power. Any changes in those proportion are conjectured to contribute towards changes in revenue function. Thus, these changes can potentially give an indication on whether the changes in power consumption distribution and tariff charge function are giving positive or negative impact on TNB revenue. Based on the finding of this study, major changes on tariff charge function seems to affect altered revenue function more than power consumption distribution. However, the paper concludes that power consumption distribution and tariff charge function can influence TNB revenue to some great extent.
Compact Deep-Space Optical Communications Transceiver

NASA Technical Reports Server (NTRS)

Roberts, W. Thomas; Charles, Jeffrey R.

2009-01-01

Deep space optical communication transceivers must be very efficient receivers and transmitters of optical communication signals. For deep space missions, communication systems require high performance well beyond the scope of mere power efficiency, demanding maximum performance in relation to the precious and limited mass, volume, and power allocated. This paper describes the opto-mechanical design of a compact, efficient, functional brassboard deep space transceiver that is capable of achieving megabyte-per-second rates at Mars ranges. The special features embodied to enhance the system operability and functionality, and to reduce the mass and volume of the system are detailed. System tests and performance characteristics are described in detail. Finally, lessons learned in the implementation of the brassboard design and suggestions for improvements appropriate for a flight prototype are covered.
Comparative study of popular objective functions for damping power system oscillations in multimachine system.

PubMed

Islam, Naz Niamul; Hannan, M A; Shareef, Hussain; Mohamed, Azah; Salam, M A

2014-01-01

Power oscillation damping controller is designed in linearized model with heuristic optimization techniques. Selection of the objective function is very crucial for damping controller design by optimization algorithms. In this research, comparative analysis has been carried out to evaluate the effectiveness of popular objective functions used in power system oscillation damping. Two-stage lead-lag damping controller by means of power system stabilizers is optimized using differential search algorithm for different objective functions. Linearized model simulations are performed to compare the dominant mode's performance and then the nonlinear model is continued to evaluate the damping performance over power system oscillations. All the simulations are conducted in two-area four-machine power system to bring a detailed analysis. Investigated results proved that multiobjective D-shaped function is an effective objective function in terms of moving unstable and lightly damped electromechanical modes into stable region. Thus, D-shape function ultimately improves overall system damping and concurrently enhances power system reliability.
Periodicity in the autocorrelation function as a mechanism for regularly occurring zero crossings or extreme values of a Gaussian process.

PubMed

Wilson, Lorna R M; Hopcraft, Keith I

2017-12-01

The problem of zero crossings is of great historical prevalence and promises extensive application. The challenge is to establish precisely how the autocorrelation function or power spectrum of a one-dimensional continuous random process determines the density function of the intervals between the zero crossings of that process. This paper investigates the case where periodicities are incorporated into the autocorrelation function of a smooth process. Numerical simulations, and statistics about the number of crossings in a fixed interval, reveal that in this case the zero crossings segue between a random and deterministic point process depending on the relative time scales of the periodic and nonperiodic components of the autocorrelation function. By considering the Laplace transform of the density function, we show that incorporating correlation between successive intervals is essential to obtaining accurate results for the interval variance. The same method enables prediction of the density function tail in some regions, and we suggest approaches for extending this to cover all regions. In an ever-more complex world, the potential applications for this scale of regularity in a random process are far reaching and powerful.
Periodicity in the autocorrelation function as a mechanism for regularly occurring zero crossings or extreme values of a Gaussian process

NASA Astrophysics Data System (ADS)

Wilson, Lorna R. M.; Hopcraft, Keith I.

2017-12-01

The problem of zero crossings is of great historical prevalence and promises extensive application. The challenge is to establish precisely how the autocorrelation function or power spectrum of a one-dimensional continuous random process determines the density function of the intervals between the zero crossings of that process. This paper investigates the case where periodicities are incorporated into the autocorrelation function of a smooth process. Numerical simulations, and statistics about the number of crossings in a fixed interval, reveal that in this case the zero crossings segue between a random and deterministic point process depending on the relative time scales of the periodic and nonperiodic components of the autocorrelation function. By considering the Laplace transform of the density function, we show that incorporating correlation between successive intervals is essential to obtaining accurate results for the interval variance. The same method enables prediction of the density function tail in some regions, and we suggest approaches for extending this to cover all regions. In an ever-more complex world, the potential applications for this scale of regularity in a random process are far reaching and powerful.
ERP Energy and Cognitive Activity Correlates

NASA Astrophysics Data System (ADS)

Schillaci, Michael Jay; Vendemia, Jennifer M. C.

2014-03-01

We propose a novel analysis approach for high-density event related scalp potential (ERP) data where the integrated channel-power is used to attain an energy density functional state for channel-clusters of neurophysiological significance. The method is applied to data recorded during a two-stimulus, directed lie paradigm and shows that deceptive responses emit between 8% and 10% less power. A time course analysis of these cognitive activity measures over posterior and anterior regions of the cortex suggests that neocortical interactions, reflecting the differing workload demands during executive and semantic processes, take about 50% longer for the case of deception. These results suggest that the proposed method may provide a useful tool for the analysis of ERP correlates of high-order cognitive functioning. We also report on a possible equivalence between the energy functional distribution and near-infrared signatures that have been measured with other modalities.
Reliability analysis using an exponential power model with bathtub-shaped failure rate function: a Bayes study.

PubMed

Shehla, Romana; Khan, Athar Ali

2016-01-01

Models with bathtub-shaped hazard function have been widely accepted in the field of reliability and medicine and are particularly useful in reliability related decision making and cost analysis. In this paper, the exponential power model capable of assuming increasing as well as bathtub-shape, is studied. This article makes a Bayesian study of the same model and simultaneously shows how posterior simulations based on Markov chain Monte Carlo algorithms can be straightforward and routine in R. The study is carried out for complete as well as censored data, under the assumption of weakly-informative priors for the parameters. In addition to this, inference interest focuses on the posterior distribution of non-linear functions of the parameters. Also, the model has been extended to include continuous explanatory variables and R-codes are well illustrated. Two real data sets are considered for illustrative purposes.
Spectroscopic imaging of metal halide high-intensity discharge lamps

NASA Astrophysics Data System (ADS)

Bonvallet, Geoffrey A.

The body of this work consists of three main research projects. An optical- and near-ultraviolet-wavelength absorption study sought to determine absolute densities of ground and excited level Sc atoms, ground level Sc + ions, and ground level Na atoms in a commercial 250 W metal halide high intensity discharge lamp during operation. These measurements also allowed the determination of the arc temperature and absolute electron density as functions of radius. Through infrared emission spectroscopy, relative densities of sodium and scandium were determined as functions of radius. Using the absolute densities gained from the optical experiment, these relative densities were calibrated. In addition, direct observation of the infrared emission allowed us to characterize the infrared power losses of the lamp. When considered as a fraction of the overall power consumption, the near-infrared spectral power losses were not substantial enough to warrant thorough investigation of their reduction in these lamps. The third project was an attempt to develop a portable x-ray diagnostic experiment. Two-dimensional spatial maps of the lamps were analyzed to determine absolute elemental mercury densities and the arc temperature as a function of radius. Two methods were used to improve the calibration of the density measurements and to correct for the spread in x-ray energy: known solutions of mercury in nitric acid, and an arc lamp which was uniformly heated to evaporate the mercury content. Although many complexities arose in this experiment, its goal was successfully completed.
The Basics: What's Essential about Theory for Community Development Practice?

ERIC Educational Resources Information Center

Hustedde, Ronald J.; Ganowicz, Jacek

2002-01-01

Relates three classical theories (structural functionalism, conflict theory, symbolic interactionism) to fundamental concerns of community development (structure, power, and shared meaning). Links these theories to Giddens' structuration theory, which connects macro and micro structures and community influence on change through cultural norms.…
Reception of Theory: Film-Television Studies and the Frankfurt School.

ERIC Educational Resources Information Center

Steinman, Clay

1988-01-01

Discusses the Critical Theory of the Frankfurt School and how it offers a way of seeing normally obscured relations of social power in the details of modern capitalist culture. Concentrates on claims about critical theory that have functioned as strategies of denial. (MS)
Professional Learning: Lessons for Supervision from Doctoral Examining

ERIC Educational Resources Information Center

Wisker, Gina; Kiley, Margaret

2014-01-01

Most research into research supervision practice focuses on functional, collegial or problematic power-related experiences. Work developing the supervisory role concentrates on new supervisors, and on taught development and support programmes. Most literature on academics' professional learning concentrates on learning to be a university teacher…
Critical Concavity of a Drainage Basin for Steady-State

NASA Astrophysics Data System (ADS)

Byun, Jongmin; Paik, Kyungrock

2015-04-01

Longitudinal profiles of natural streams are known to show concave forms. Saying A as drainage area, channel gradient S can be expressed as the power-law, S≈A-θ (Flint, 1974), which is one of the scale-invariant features of drainage basin. According to literature, θ of most natural streams falls into a narrow range (0.4 < θ < 0.7) (Tucker and Whipple, 2002). It leads to fundamental questions: 'Why does θ falls into such narrow range?' and 'How is this related with other power-law scaling relationships reported in natural drainage basins?' To answer above questions, we analytically derive θ for a steady-state drainage basin following Lane's equilibrium (Lane, 1955) throughout the corridor and named this specific case as the 'critical concavity'. In the derivation, sediment transport capacity is estimated by unit stream power model (Yang, 1976), yielding a power function of upstream area. Stability of channel at a local point occurs when incoming flux equals outgoing flux at the point. Therefore, given the drainage at steady-state where all channel beds are stable, the exponent of the power function should be zero. From this, we can determine the critical concavity. Considering ranges of variables associated in this derivation, critical concavity cannot be resolved as a single definite value, rather a range of critical concavity is suggested. This range well agrees with the widely reported range of θ (0.4 < θ < 0.7) in natural streams. In this theoretical study, inter-relationships between power-laws such as hydraulic geometry (Leopold and Maddock, 1953), dominant discharge-drainage area (Knighton et al., 1999), and concavity, are coupled into the power-law framework of stream power sediment transport model. This allows us to explore close relationships between their power-law exponents: their relative roles and sensitivity. Detailed analysis and implications will be presented. References Flint, J. J., 1974, Stream gradient as a function of order, magnitude, and discharge, Water Resources Research, 10, 969-973. Knighton, A. D., 1999, Downstream variation in stream power, Geomorphology, 29, 293-306. Lane, E. W., 1955, The importance of fluvial morphology in hydraulic engineering, American Society of Civil Engineers, Proceedings, 81, 1-17 Leopold, L. B., Maddock, T., 1953, The hydraulic geometry of stream channels and some physiographic implications, United States Government Printing Office, 1953. Tucker, G. E., Whipple, K. X., 2002, Topographic outcomes predicted by stream erosion models: Sensitivity analysis and intermodel comparison, Journal of Geophysical Research, 107(B9), 2179, doi:10.1029/2001JB000162, 2002. Yang, C. T., 1976, Minimum unit stream power and fluvial hydraulics, Journal of Hydraulics Division, ASCE 102, 919-934.
Variability comparison of simultaneous brain near-infrared spectroscopy (NIRS) and functional MRI (fMRI) during visual stimulation

PubMed Central

Minati, Ludovico; Visani, Elisa; Dowell, Nick G; Medford, Nick; Critchley, Hugo D

2011-01-01

Brain near-infrared spectroscopy (NIRS) is emerging as a potential alternative to functional MRI (fMRI). To date, no study has explicitly compared the two techniques in terms of measurement variability, a key parameter dictating attainable statistical power. Here, NIRS and fMRI were simultaneously recorded during event-related visual stimulation. Inter-subject coefficients of variation (CVs) for peak response amplitude were considerably larger for NIRS than fMRI, but inter-subject CVs for response latency and intra-subject CVs for response amplitude were overall comparable. Our results may represent an optimistic estimate of the CVs of NIRS measurements, as optode positioning was guided by structural MRI, which is normally unavailable. We conclude that fMRI may be preferable to NIRS for group comparisons, but NIRS is equally powerful when comparing conditions within participants. The discrepancy between inter- and intra-subject CVs is likely related to variability in head anatomy and tissue properties which may be better accounted for by emerging NIRS technology. PMID:21780948
Dual regression physiological modeling of resting-state EPI power spectra: Effects of healthy aging.

PubMed

Viessmann, Olivia; Möller, Harald E; Jezzard, Peter

2018-02-02

Aging and disease-related changes in the arteriovasculature have been linked to elevated levels of cardiac cycle-induced pulsatility in the cerebral microcirculation. Functional magnetic resonance imaging (fMRI), acquired fast enough to unalias the cardiac frequency contributions, can be used to study these physiological signals in the brain. Here, we propose an iterative dual regression analysis in the frequency domain to model single voxel power spectra of echo planar imaging (EPI) data using external recordings of the cardiac and respiratory cycles as input. We further show that a data-driven variant, without external physiological traces, produces comparable results. We use this framework to map and quantify cardiac and respiratory contributions in healthy aging. We found a significant increase in the spatial extent of cardiac modulated white matter voxels with age, whereas the overall strength of cardiac-related EPI power did not show an age effect. Copyright © 2018. Published by Elsevier Inc.
Relativity, nonextensivity, and extended power law distributions.

PubMed

Silva, R; Lima, J A S

2005-11-01

A proof of the relativistic theorem by including nonextensive effects is given. As it happens in the nonrelativistic limit, the molecular chaos hypothesis advanced by Boltzmann does not remain valid, and the second law of thermodynamics combined with a duality transformation implies that the parameter lies on the interval [0,2]. It is also proven that the collisional equilibrium states (null entropy source term) are described by the relativistic power law extension of the exponential Juttner distribution which reduces, in the nonrelativistic domain, to the Tsallis power law function. As a simple illustration of the basic approach, we derive the relativistic nonextensive equilibrium distribution for a dilute charged gas under the action of an electromagnetic field . Such results reduce to the standard ones in the extensive limit, thereby showing that the nonextensive entropic framework can be harmonized with the space-time ideas contained in the special relativity theory.
Sector magnets or transverse electromagnetic fields in cylindrical coordinates

DOE PAGES

Zolkin, T.

2017-04-10

Laplace’s equation is considered for scalar and vector potentials describing electric or magnetic fields in cylindrical coordinates, with invariance along the azimuthal coordinate. In a series, we found special functions which, when expanded to lowest order in power series in radial and vertical coordinates, replicate harmonic polynomials in two variables. These functions are based on radial harmonics found by Edwin M. McMillan forty years ago. In addition to McMillan’s harmonics, a second family of radial harmonics is introduced to provide a symmetric description between electric and magnetic fields and to describe fields and potentials in terms of the same functions.more » Formulas are provided which relate any transverse fields specified by the coefficients in the power series expansion in radial or vertical planes in cylindrical coordinates with the set of new functions. Our result is important for potential theory and for theoretical study, design and proper modeling of sector dipoles, combined function dipoles and any general sector element for accelerator physics. All results are presented in connection with these problems.« less
Exact analytic solution of position-dependent mass Schrödinger equation

NASA Astrophysics Data System (ADS)

Rajbongshi, Hangshadhar

2018-03-01

Exact analytic solution of position-dependent mass Schrödinger equation is generated by using extended transformation, a method of mapping a known system into a new system equipped with energy eigenvalues and corresponding wave functions. First order transformation is performed on D-dimensional radial Schrödinger equation with constant mass by taking trigonometric Pöschl-Teller potential as known system. The exactly solvable potentials with position-dependent mass generated for different choices of mass functions through first order transformation are also taken as known systems in the second order transformation performed on D-dimensional radial position-dependent mass Schrödinger equation. The solutions are fitted for "Zhu and Kroemer" ordering of ambiguity. All the wave functions corresponding to nonzero energy eigenvalues are normalizable. The new findings are that the normalizability condition of the wave functions remains independent of mass functions, and some of the generated potentials show a family relationship among themselves where power law potentials also get related to non-power law potentials and vice versa through the transformation.
Sector magnets or transverse electromagnetic fields in cylindrical coordinates

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

Zolkin, T.

Laplace’s equation is considered for scalar and vector potentials describing electric or magnetic fields in cylindrical coordinates, with invariance along the azimuthal coordinate. In a series, we found special functions which, when expanded to lowest order in power series in radial and vertical coordinates, replicate harmonic polynomials in two variables. These functions are based on radial harmonics found by Edwin M. McMillan forty years ago. In addition to McMillan’s harmonics, a second family of radial harmonics is introduced to provide a symmetric description between electric and magnetic fields and to describe fields and potentials in terms of the same functions.more » Formulas are provided which relate any transverse fields specified by the coefficients in the power series expansion in radial or vertical planes in cylindrical coordinates with the set of new functions. Our result is important for potential theory and for theoretical study, design and proper modeling of sector dipoles, combined function dipoles and any general sector element for accelerator physics. All results are presented in connection with these problems.« less
Bidirectional DC/DC Converter

NASA Astrophysics Data System (ADS)

Pedersen, F.

2008-09-01

The presented bidirectional DC/DC converter design concept is a further development of an already existing converter used for low battery voltage operation.For low battery voltage operation a high efficient low parts count DC/DC converter was developed, and used in a satellite for the battery charge and battery discharge function.The converter consists in a bidirectional, non regulating DC/DC converter connected to a discharge regulating Buck converter and a charge regulating Buck converter.The Bidirectional non regulating DC/DC converter performs with relatively high efficiency even at relatively high currents, which here means up to 35Amps.This performance was obtained through the use of power MOSFET's with on- resistances of only a few mille Ohms connected to a special transformer allowing paralleling several transistor stages on the low voltage side of the transformer. The design is patent protected. Synchronous rectification leads to high efficiency at the low battery voltages considered, which was in the range 2,7- 4,3 Volt DC.The converter performs with low switching losses as zero voltage zero current switching is implemented in all switching positions of the converter.Now, the drive power needed, to switch a relatively large number of low Ohm , hence high drive capacitance, power MOSFET's using conventional drive techniques would limit the overall conversion efficiency.Therefore a resonant drive consuming considerable less power than a conventional drive circuit was implemented in the converter.To the originally built and patent protected bidirectional non regulating DC/DC converter, is added the functionality of regulation.Hereby the need for additional converter stages in form of a Charge Buck regulator and a Discharge Buck regulator is eliminated.The bidirectional DC/DC converter can be used in connection with batteries, motors, etc, where the bidirectional feature, simple design and high performance may be useful.

Fluctuation scaling in the visual cortex at threshold

NASA Astrophysics Data System (ADS)

Medina, José M.; Díaz, José A.

2016-05-01

Fluctuation scaling relates trial-to-trial variability to the average response by a power function in many physical processes. Here we address whether fluctuation scaling holds in sensory psychophysics and its functional role in visual processing. We report experimental evidence of fluctuation scaling in human color vision and form perception at threshold. Subjects detected thresholds in a psychophysical masking experiment that is considered a standard reference for studying suppression between neurons in the visual cortex. For all subjects, the analysis of threshold variability that results from the masking task indicates that fluctuation scaling is a global property that modulates detection thresholds with a scaling exponent that departs from 2, β =2.48 ±0.07 . We also examine a generalized version of fluctuation scaling between the sample kurtosis K and the sample skewness S of threshold distributions. We find that K and S are related and follow a unique quadratic form K =(1.19 ±0.04 ) S2+(2.68 ±0.06 ) that departs from the expected 4/3 power function regime. A random multiplicative process with weak additive noise is proposed based on a Langevin-type equation. The multiplicative process provides a unifying description of fluctuation scaling and the quadratic S -K relation and is related to on-off intermittency in sensory perception. Our findings provide an insight into how the human visual system interacts with the external environment. The theoretical methods open perspectives for investigating fluctuation scaling and intermittency effects in a wide variety of natural, economic, and cognitive phenomena.
From Finite Time to Finite Physical Dimensions Thermodynamics: The Carnot Engine and Onsager's Relations Revisited

NASA Astrophysics Data System (ADS)

Feidt, Michel; Costea, Monica

2018-04-01

Many works have been devoted to finite time thermodynamics since the Curzon and Ahlborn [1] contribution, which is generally considered as its origin. Nevertheless, previous works in this domain have been revealed [2], [3], and recently, results of the attempt to correlate Finite Time Thermodynamics with Linear Irreversible Thermodynamics according to Onsager's theory were reported [4]. The aim of the present paper is to extend and improve the approach relative to thermodynamic optimization of generic objective functions of a Carnot engine with linear response regime presented in [4]. The case study of the Carnot engine is revisited within the steady state hypothesis, when non-adiabaticity of the system is considered, and heat loss is accounted for by an overall heat leak between the engine heat reservoirs. The optimization is focused on the main objective functions connected to engineering conditions, namely maximum efficiency or power output, except the one relative to entropy that is more fundamental. Results given in reference [4] relative to the maximum power output and minimum entropy production as objective function are reconsidered and clarified, and the change from finite time to finite physical dimension was shown to be done by the heat flow rate at the source. Our modeling has led to new results of the Carnot engine optimization and proved that the primary interest for an engineer is mainly connected to what we called Finite Physical Dimensions Optimal Thermodynamics.
Consistency relations for sharp inflationary non-Gaussian features

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

Mooij, Sander; Palma, Gonzalo A.; Panotopoulos, Grigoris

If cosmic inflation suffered tiny time-dependent deviations from the slow-roll regime, these would induce the existence of small scale-dependent features imprinted in the primordial spectra, with their shapes and sizes revealing information about the physics that produced them. Small sharp features could be suppressed at the level of the two-point correlation function, making them undetectable in the power spectrum, but could be amplified at the level of the three-point correlation function, offering us a window of opportunity to uncover them in the non-Gaussian bispectrum. In this article, we show that sharp features may be analyzed using only data coming frommore » the three point correlation function parametrizing primordial non-Gaussianity. More precisely, we show that if features appear in a particular non-Gaussian triangle configuration (e.g. equilateral, folded, squeezed), these must reappear in every other configuration according to a specific relation allowing us to correlate features across the non-Gaussian bispectrum. As a result, we offer a method to study scale-dependent features generated during inflation that depends only on data coming from measurements of non-Gaussianity, allowing us to omit data from the power spectrum.« less
Physical Function in Older Men With Hyperkyphosis

PubMed Central

Harrison, Stephanie L.; Fink, Howard A.; Marshall, Lynn M.; Orwoll, Eric; Barrett-Connor, Elizabeth; Cawthon, Peggy M.; Kado, Deborah M.

2015-01-01

Background. Age-related hyperkyphosis has been associated with poor physical function and is a well-established predictor of adverse health outcomes in older women, but its impact on health in older men is less well understood. Methods. We conducted a cross-sectional study to evaluate the association of hyperkyphosis and physical function in 2,363 men, aged 71–98 (M = 79) from the Osteoporotic Fractures in Men Study. Kyphosis was measured using the Rancho Bernardo Study block method. Measurements of grip strength and lower extremity function, including gait speed over 6 m, narrow walk (measure of dynamic balance), repeated chair stands ability and time, and lower extremity power (Nottingham Power Rig) were included separately as primary outcomes. We investigated associations of kyphosis and each outcome in age-adjusted and multivariable linear or logistic regression models, controlling for age, clinic, education, race, bone mineral density, height, weight, diabetes, and physical activity. Results. In multivariate linear regression, we observed a dose-related response of worse scores on each lower extremity physical function test as number of blocks increased, p for trend ≤.001. Using a cutoff of ≥4 blocks, 20% (N = 469) of men were characterized with hyperkyphosis. In multivariate logistic regression, men with hyperkyphosis had increased odds (range 1.5–1.8) of being in the worst quartile of performing lower extremity physical function tasks (p < .001 for each outcome). Kyphosis was not associated with grip strength in any multivariate analysis. Conclusions. Hyperkyphosis is associated with impaired lower extremity physical function in older men. Further studies are needed to determine the direction of causality. PMID:25431353
Discriminative analysis of non-linear brain connectivity for leukoaraiosis with resting-state fMRI

NASA Astrophysics Data System (ADS)

Lai, Youzhi; Xu, Lele; Yao, Li; Wu, Xia

2015-03-01

Leukoaraiosis (LA) describes diffuse white matter abnormalities on CT or MR brain scans, often seen in the normal elderly and in association with vascular risk factors such as hypertension, or in the context of cognitive impairment. The mechanism of cognitive dysfunction is still unclear. The recent clinical studies have revealed that the severity of LA was not corresponding to the cognitive level, and functional connectivity analysis is an appropriate method to detect the relation between LA and cognitive decline. However, existing functional connectivity analyses of LA have been mostly limited to linear associations. In this investigation, a novel measure utilizing the extended maximal information coefficient (eMIC) was applied to construct non-linear functional connectivity in 44 LA subjects (9 dementia, 25 mild cognitive impairment (MCI) and 10 cognitively normal (CN)). The strength of non-linear functional connections for the first 1% of discriminative power increased in MCI compared with CN and dementia, which was opposed to its linear counterpart. Further functional network analysis revealed that the changes of the non-linear and linear connectivity have similar but not completely the same spatial distribution in human brain. In the multivariate pattern analysis with multiple classifiers, the non-linear functional connectivity mostly identified dementia, MCI and CN from LA with a relatively higher accuracy rate than the linear measure. Our findings revealed the non-linear functional connectivity provided useful discriminative power in classification of LA, and the spatial distributed changes between the non-linear and linear measure may indicate the underlying mechanism of cognitive dysfunction in LA.
Analyzing Effects of Turbulence on Power Generation Using Wind Plant Monitoring Data: Preprint

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

Zhang, J.; Chowdhury, S.; Hodge, B. M.

2014-01-01

In this paper, a methodology is developed to analyze how ambient and wake turbulence affects the power generation of a single wind turbine within an array of turbines. Using monitoring data from a wind power plant, we selected two sets of wind and power data for turbines on the edge of the wind plant that resemble (i) an out-of-wake scenario (i.e., when the turbine directly faces incoming winds) and (ii) an in-wake scenario (i.e., when the turbine is under the wake of other turbines). For each set of data, two surrogate models were then developed to represent the turbine powermore » generation (i) as a function of the wind speed; and (ii) as a function of the wind speed and turbulence intensity. Support vector regression was adopted for the development of the surrogate models. Three types of uncertainties in the turbine power generation were also investigated: (i) the uncertainty in power generation with respect to the published/reported power curve, (ii) the uncertainty in power generation with respect to the estimated power response that accounts for only mean wind speed; and (iii) the uncertainty in power generation with respect to the estimated power response that accounts for both mean wind speed and turbulence intensity. Results show that (i) under the same wind conditions, the turbine generates different power between the in-wake and out-of-wake scenarios, (ii) a turbine generally produces more power under the in-wake scenario than under the out-of-wake scenario, (iii) the power generation is sensitive to turbulence intensity even when the wind speed is greater than the turbine rated speed, and (iv) there is relatively more uncertainty in the power generation under the in-wake scenario than under the out-of-wake scenario.« less
The Power of Story

NASA Technical Reports Server (NTRS)

Cohen, Don; Fox, Jessica

2008-01-01

A major knowledge-sharing issue that is the source of many project problems: how to communicate our intentions so that the information received is the same as the information given. One answer is conversation-the back-and-forth of statement, question, and response that gradually brings talkers and listeners to a shared understanding. Stories also offer a way to share knowledge effectively. While the story teller's intent and the listener's interpretation will not be identical, a good story reliably communicates essential knowledge so it is not only understood but absorbed and embraced. Narrative is one of the oldest knowledge-transfer systems in the world. Religion knows it. Politicians know it. Fairytales know it. Now, knowledge management practitioners are coming to know it, too. But why are stories such a powerful knowledge-transfer tool? And what kinds of knowledge do they transfer? Joseph Campbell, the mythologist, defined stories as serving four major functions: the mystical, the cosmological, the sociological, and the pedagogical. The mystical function of narrative lies in its ability to open up emotional realization that often connects with a transcendent idea such as love or forgiveness. He calls this realization "mystical" because it connects the self with the universal. What Campbell calls the cosmological function of stories relates the self to the outside world, focusing on action, on understanding cause and effect and our role in it. For the cosmological function of stories "to be up to date and really to work in the minds of people who are living in the modern scientific world," Campbell notes, "it must incorporate the modern scientific world." We must continually tell stories that demonstrate our current vision of the world. The sociological function of stories, Campbell explains, helps maintain and validate the social order of a society. Stories pass on information about power relationships, taboos, laws, and the inner workings of communities. Countries and religions have stories that serve this function and so do organizations and project teams, where stories about project work communicate information about behaviors and attitudes that are expected and rewarded or frowned upon and penalized. Functioning pedagogically, says Campbell, narratives guide individuals harmoniously through the stages of life in terms of their world today, with its current goods, values, and dangers. These are stories that deal with life transitions and guide us from one stage to another. Stories powerfully serve these functions partly because of two great strengths: their ability to engage listeners personally and emotionally and their use of metaphor. And it turns out that these two things are related.
A Study of the Thermal Environment Developed by a Traveling Slipper at High Velocity

DTIC Science & Technology

2013-03-01

Power Partition Function The next partition function takes the same formulation as the powered function but now the exponent is squared. The...function and note the squared term in the exponent . 66 Equation 4.27 (4.36) Thus far the three partition functions each give a predicted...hypothesized that the function would fall somewhere between the first exponential decay function and the power function. However, by squaring the exponent
The effects of message recipients' power before and after persuasion: a self-validation analysis.

PubMed

Briñol, Pablo; Petty, Richard E; Valle, Carmen; Rucker, Derek D; Becerra, Alberto

2007-12-01

In the present research, the authors examined the effect of a message recipient's power on attitude change and introduced a new mechanism by which power can affect social judgment. In line with prior research that suggested a link between power and approach tendencies, the authors hypothesized that having power increases confidence relative to being powerless. After demonstrating this link in Experiment 1, in 4 additional studies, they examined the role of power in persuasion as a function of when power is infused into the persuasion process. On the basis of the idea that power validates whatever mental content is accessible, they hypothesized that power would have different effects on persuasion depending on when power was induced. Specifically, the authors predicted that making people feel powerful prior to a message would validate their existing views and thus reduce the perceived need to attend to subsequent information. However, it was hypothesized that inducing power after a message has been processed would validate one's recently generated thoughts and thus influence the extent to which people rely upon their thoughts in determining their attitudes. (c) 2007 APA, all rights reserved.
Power System Test and Verification at Satellite Level

NASA Astrophysics Data System (ADS)

Simonelli, Giulio; Mourra, Olivier; Tonicello, Ferdinando

2008-09-01

Most of the articles on Power Systems deal with the architecture and technical solutions related to the functionalities of the power system and their performances. Very few articles, if none, address integration and verification aspects of the Power System at satellite level and the related issues with the Power EGSE (Electrical Ground Support Equipment), which, also, have to support the AIT/AIV (Assembly Integration Test and Verification) program of the satellite and, eventually, the launch campaign. In the last years a more complex development and testing concept based on MDVE (Model Based Development and Verification Environment) has been introduced. In the MDVE approach the simulation software is used to simulate the Satellite environment and, in the early stages, the satellites units. This approach changed significantly the Power EGSE requirements. Power EGSEs or, better, Power SCOEs (Special Check Out Equipment) are now requested to provide the instantaneous power generated by the solar array throughout the orbit. To achieve that, the Power SCOE interfaces to the RTS (Real Time Simulator) of the MDVE. The RTS provides the instantaneous settings, which belong to that point along the orbit, to the Power SCOE so that the Power SCOE generates the instantaneous {I,V} curve of the SA (Solar Array). That means a real time test for the power system, which is even more valuable for EO (Earth Observation) satellites where the Solar Array aspect angle to the sun is rarely fixed, and the power load profile can be particularly complex (for example, in radar applications). In this article the major issues related to integration and testing of Power Systems will be discussed taking into account different power system topologies (i.e. regulated bus, unregulated bus, battery bus, based on MPPT or S3R…). Also aspects about Power System AIT I/Fs (interfaces) and Umbilical I/Fs with the launcher and the Power SCOE I/Fs will be addressed. Last but not least, protection strategy of the Power System during AIT/AIV program will also be discussed. The objective of this discussion is also to provide the Power System Engineer with a checklist of key aspects linked to the satellite AIT/AIV program, that have to be considered in the early phases of a new power system development.
Whole-Genome DNA Methylation Status Associated with Clinical PTSD Measures of OIF/OEF Veterans (Open Access)

DTIC Science & Technology

2017-07-11

Significantly enriched networks with similar functional purposes were grouped together, resulting in four network clusters (Figure 1): nervous system...relatively conservative estimate for the mean difference (that is, top 1%), 76 people per group should give 95% power to detect an individual probe...CpGIs curated from the training set were enriched for four functional clusters: PTSD-associated somatic complications, PTSD-relevant endocrine signaling
Explore, Visualize, and Analyze Functional Cancer Proteomic Data Using the Cancer Proteome Atlas. | Office of Cancer Genomics

Cancer.gov

Reverse-phase protein arrays (RPPA) represent a powerful functional proteomic approach to elucidate cancer-related molecular mechanisms and to develop novel cancer therapies. To facilitate community-based investigation of the large-scale protein expression data generated by this platform, we have developed a user-friendly, open-access bioinformatic resource, The Cancer Proteome Atlas (TCPA, http://tcpaportal.org), which contains two separate web applications.
EEG-MEG Integration Enhances the Characterization of Functional and Effective Connectivity in the Resting State Network

PubMed Central

Mideksa, Kidist Gebremariam; Anwar, Abdul Rauf; Stephani, Ulrich; Deuschl, Günther; Freitag, Christine M.; Siniatchkin, Michael

2015-01-01

At the sensor level many aspects, such as spectral power, functional and effective connectivity as well as relative-power-ratio ratio (RPR) and spatial resolution have been comprehensively investigated through both electroencephalography (EEG) and magnetoencephalography (MEG). Despite this, differences between both modalities have not yet been systematically studied by direct comparison. It remains an open question as to whether the integration of EEG and MEG data would improve the information obtained from the above mentioned parameters. Here, EEG (64-channel system) and MEG (275 sensor system) were recorded simultaneously in conditions with eyes open (EO) and eyes closed (EC) in 29 healthy adults. Spectral power, functional and effective connectivity, RPR, and spatial resolution were analyzed at five different frequency bands (delta, theta, alpha, beta and gamma). Networks of functional and effective connectivity were described using a spatial filter approach called the dynamic imaging of coherent sources (DICS) followed by the renormalized partial directed coherence (RPDC). Absolute mean power at the sensor level was significantly higher in EEG than in MEG data in both EO and EC conditions. At the source level, there was a trend towards a better performance of the combined EEG+MEG analysis compared with separate EEG or MEG analyses for the source mean power, functional correlation, effective connectivity for both EO and EC. The network of coherent sources and the spatial resolution were similar for both the EEG and MEG data if they were analyzed separately. Results indicate that the combined approach has several advantages over the separate analyses of both EEG and MEG. Moreover, by a direct comparison of EEG and MEG, EEG was characterized by significantly higher values in all measured parameters in both sensor and source level. All the above conclusions are specific to the resting state task and the specific analysis used in this study to have general conclusion multi-center studies would be helpful. PMID:26509448
Automated Power Systems Management (APSM)

NASA Technical Reports Server (NTRS)

Bridgeforth, A. O.

1981-01-01

A breadboard power system incorporating autonomous functions of monitoring, fault detection and recovery, command and control was developed, tested and evaluated to demonstrate technology feasibility. Autonomous functions including switching of redundant power processing elements, individual load fault removal, and battery charge/discharge control were implemented by means of a distributed microcomputer system within the power subsystem. Three local microcomputers provide the monitoring, control and command function interfaces between the central power subsystem microcomputer and the power sources, power processing and power distribution elements. The central microcomputer is the interface between the local microcomputers and the spacecraft central computer or ground test equipment.
QUESPOWR MRI: QUantification of Exchange as a function of Saturation Power On the Water Resonance

PubMed Central

Randtke, Edward A.; Pagel, Mark D.; Cárdenas-Rodríguez, Julio

2018-01-01

QUantification of Exchange as a function of Saturation Power On the Water Resonance (QUESPOWR) MRI is a new method that can estimate chemical exchange rates. This method acquires a series of OPARACHEE MRI acquisitions with a range of RF powers for the WALTZ16* pulse train, which are applied on the water resonance. A QUESPOWR plot can be generated from the power dependence of the % water signal, which is similar to a QUESP plot that is generated from CEST MRI acquisition methods with RF saturation applied off-resonance from water. A QUESPOWR plot can be quantitatively analyzed using linear fitting methods to provide estimates of average chemical exchange rates. Analyses of the shapes of QUESPOWR plots can also be used to estimate relative differences in average chemical exchange rates and concentrations of biomolecules. The performance of QUESPOWR MRI was assessed via simulations, an in vitro study with iopamidol, and an in vivo study with a mouse model of mammary carcinoma. The results showed that QUESPOWR MRI is especially sensitive to chemical exchange between water and biomolecules that have intermediate to fast chemical exchange rates and chemical shifts that are close to water, which are notoriously difficult to assess with other CEST MRI methods. In addition, in vivo QUESPOWR MRI detected acidic tumor tissues relative to normal tissues that are pH-neutral, and therefore may be a new paradigm for tumor detection with MRI. PMID:27404128
Generating log-normal mock catalog of galaxies in redshift space

NASA Astrophysics Data System (ADS)

Agrawal, Aniket; Makiya, Ryu; Chiang, Chi-Ting; Jeong, Donghui; Saito, Shun; Komatsu, Eiichiro

2017-10-01

We present a public code to generate a mock galaxy catalog in redshift space assuming a log-normal probability density function (PDF) of galaxy and matter density fields. We draw galaxies by Poisson-sampling the log-normal field, and calculate the velocity field from the linearised continuity equation of matter fields, assuming zero vorticity. This procedure yields a PDF of the pairwise velocity fields that is qualitatively similar to that of N-body simulations. We check fidelity of the catalog, showing that the measured two-point correlation function and power spectrum in real space agree with the input precisely. We find that a linear bias relation in the power spectrum does not guarantee a linear bias relation in the density contrasts, leading to a cross-correlation coefficient of matter and galaxies deviating from unity on small scales. We also find that linearising the Jacobian of the real-to-redshift space mapping provides a poor model for the two-point statistics in redshift space. That is, non-linear redshift-space distortion is dominated by non-linearity in the Jacobian. The power spectrum in redshift space shows a damping on small scales that is qualitatively similar to that of the well-known Fingers-of-God (FoG) effect due to random velocities, except that the log-normal mock does not include random velocities. This damping is a consequence of non-linearity in the Jacobian, and thus attributing the damping of the power spectrum solely to FoG, as commonly done in the literature, is misleading.
Power increases the socially toxic component of narcissism among individuals with high baseline testosterone.

PubMed

Mead, Nicole L; Baumeister, Roy F; Stuppy, Anika; Vohs, Kathleen D

2018-04-01

The corrosive effects of power have been noted for centuries, but the self-related changes responsible for those effects have remained somewhat elusive. Narcissists tend to rise to-and abuse-positions of power, so we considered the possibility that positions of power may corrupt because they inflate narcissism. Two pathways were considered: Powerholders abuse their power because having power over others makes them feel superior (grandiosity pathway) or deserving of special treatment (entitlement pathway). Supporting the entitlement pathway, assigning participants to a position of power (vs. equal control) over a group task increased scores on the Exploitative/Entitlement component of narcissism among those with high baseline testosterone. What is more, heightened Exploitative/Entitlement scores among high-testosterone participants endowed with power (vs. equal control) statistically explained amplified self-reported willingness to misuse their power (e.g., taking fringe benefits as extra compensation). The grandiosity pathway was not well supported. The Superiority/Arrogance, Self-Absorption/Self-Admiration, and Leadership/Authority facets of narcissism did not change as a function of the power manipulation and testosterone levels. Taken together, these results suggest that people with high (but not low) testosterone may be inclined to misuse their power because having power over others makes them feel entitled to special treatment. This work identifies testosterone as a characteristic that contributes to the development of the socially toxic component of narcissism (Exploitative/Entitlement). It points to the possibility that structural positions of power and individual differences in narcissism may be mutually reinforcing, suggesting a vicious cycle with personal, relational, and societal implications. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Summary goodness-of-fit statistics for binary generalized linear models with noncanonical link functions.

PubMed

Canary, Jana D; Blizzard, Leigh; Barry, Ronald P; Hosmer, David W; Quinn, Stephen J

2016-05-01

Generalized linear models (GLM) with a canonical logit link function are the primary modeling technique used to relate a binary outcome to predictor variables. However, noncanonical links can offer more flexibility, producing convenient analytical quantities (e.g., probit GLMs in toxicology) and desired measures of effect (e.g., relative risk from log GLMs). Many summary goodness-of-fit (GOF) statistics exist for logistic GLM. Their properties make the development of GOF statistics relatively straightforward, but it can be more difficult under noncanonical links. Although GOF tests for logistic GLM with continuous covariates (GLMCC) have been applied to GLMCCs with log links, we know of no GOF tests in the literature specifically developed for GLMCCs that can be applied regardless of link function chosen. We generalize the Tsiatis GOF statistic originally developed for logistic GLMCCs, (TG), so that it can be applied under any link function. Further, we show that the algebraically related Hosmer-Lemeshow (HL) and Pigeon-Heyse (J(2) ) statistics can be applied directly. In a simulation study, TG, HL, and J(2) were used to evaluate the fit of probit, log-log, complementary log-log, and log models, all calculated with a common grouping method. The TG statistic consistently maintained Type I error rates, while those of HL and J(2) were often lower than expected if terms with little influence were included. Generally, the statistics had similar power to detect an incorrect model. An exception occurred when a log GLMCC was incorrectly fit to data generated from a logistic GLMCC. In this case, TG had more power than HL or J(2) . © 2015 John Wiley & Sons Ltd/London School of Economics.
Advances in Relating Eye Movements and Cognition

ERIC Educational Resources Information Center

Hayhoe, Mary M.

2004-01-01

Measurement of eye movements is a powerful tool for investigating perceptual and cognitive function in both infants and adults. Straightforwardly, eye movements provide a multifaceted measure of performance. For example, the location of fixations, their duration, time of occurrence, and accuracy all are potentially revealing and often allow…
Teaching the Holocaust through Film.

ERIC Educational Resources Information Center

Michalczyk, John J.

The use of Holocaust-related films and Holocaust survivors as classroom resources is analyzed. The perspective and function of four film genres are outlined as follows. Newsreels, made by the Nazis to chronicle their "progress," provide powerful raw footage of the concentration camp experience. Documentaries, generally made by Allied…

Identifying reprioritization response shift in a stroke caregiver population: a comparison of missing data methods.

PubMed

Sajobi, Tolulope T; Lix, Lisa M; Singh, Gurbakhshash; Lowerison, Mark; Engbers, Jordan; Mayo, Nancy E

2015-03-01

Response shift (RS) is an important phenomenon that influences the assessment of longitudinal changes in health-related quality of life (HRQOL) studies. Given that RS effects are often small, missing data due to attrition or item non-response can contribute to failure to detect RS effects. Since missing data are often encountered in longitudinal HRQOL data, effective strategies to deal with missing data are important to consider. This study aims to compare different imputation methods on the detection of reprioritization RS in the HRQOL of caregivers of stroke survivors. Data were from a Canadian multi-center longitudinal study of caregivers of stroke survivors over a one-year period. The Stroke Impact Scale physical function score at baseline, with a cutoff of 75, was used to measure patient stroke severity for the reprioritization RS analysis. Mean imputation, likelihood-based expectation-maximization imputation, and multiple imputation methods were compared in test procedures based on changes in relative importance weights to detect RS in SF-36 domains over a 6-month period. Monte Carlo simulation methods were used to compare the statistical powers of relative importance test procedures for detecting RS in incomplete longitudinal data under different missing data mechanisms and imputation methods. Of the 409 caregivers, 15.9 and 31.3 % of them had missing data at baseline and 6 months, respectively. There were no statistically significant changes in relative importance weights on any of the domains when complete-case analysis was adopted. But statistical significant changes were detected on physical functioning and/or vitality domains when mean imputation or EM imputation was adopted. There were also statistically significant changes in relative importance weights for physical functioning, mental health, and vitality domains when multiple imputation method was adopted. Our simulations revealed that relative importance test procedures were least powerful under complete-case analysis method and most powerful when a mean imputation or multiple imputation method was adopted for missing data, regardless of the missing data mechanism and proportion of missing data. Test procedures based on relative importance measures are sensitive to the type and amount of missing data and imputation method. Relative importance test procedures based on mean imputation and multiple imputation are recommended for detecting RS in incomplete data.
18 CFR 11.12 - Determination of section 10(f) costs.

Code of Federal Regulations, 2010 CFR

2010-04-01

... costs of the project. (2) If power is not an authorized function of the headwater project, the section... costs designated as the joint-use power cost, derived by deeming a power function at the project. The value of the benefits assigned to the deemed power function, for purposes of determining the value of...
18 CFR 11.12 - Determination of section 10(f) costs.

Code of Federal Regulations, 2012 CFR

2012-04-01

... costs of the project. (2) If power is not an authorized function of the headwater project, the section... costs designated as the joint-use power cost, derived by deeming a power function at the project. The value of the benefits assigned to the deemed power function, for purposes of determining the value of...
18 CFR 11.12 - Determination of section 10(f) costs.

Code of Federal Regulations, 2011 CFR

2011-04-01

... costs of the project. (2) If power is not an authorized function of the headwater project, the section... costs designated as the joint-use power cost, derived by deeming a power function at the project. The value of the benefits assigned to the deemed power function, for purposes of determining the value of...
18 CFR 11.12 - Determination of section 10(f) costs.

Code of Federal Regulations, 2014 CFR

2014-04-01

... costs of the project. (2) If power is not an authorized function of the headwater project, the section... costs designated as the joint-use power cost, derived by deeming a power function at the project. The value of the benefits assigned to the deemed power function, for purposes of determining the value of...
18 CFR 11.12 - Determination of section 10(f) costs.

Code of Federal Regulations, 2013 CFR

2013-04-01

... costs of the project. (2) If power is not an authorized function of the headwater project, the section... costs designated as the joint-use power cost, derived by deeming a power function at the project. The value of the benefits assigned to the deemed power function, for purposes of determining the value of...
Changes in Cognitive Performance Are Associated with Changes in Sleep in Older Adults With Insomnia.

PubMed

Wilckens, Kristine A; Hall, Martica H; Nebes, Robert D; Monk, Timothy H; Buysse, Daniel J

2016-01-01

The present study examined sleep features associated with cognition in older adults and examined whether sleep changes following insomnia treatment were associated with cognitive improvements. Polysomnography and cognition (recall, working memory, and reasoning) were assessed before and after an insomnia intervention (Brief Behavioral Treatment of Insomnia [BBTI] or information control [IC]) in 77 older adults with insomnia. Baseline wake-after-sleep-onset (WASO) was associated with recall. Greater NREM (nonrapid eye movement) delta power and lower NREM sigma power were associated with greater working memory and reasoning. The insomnia intervention did not improve performance. However, increased absolute delta power and decreased relative sigma power were associated with improved reasoning. Findings suggest that improvements in executive function may occur with changes in NREM architecture.
Practical application of power conditioning to electric propulsion for passenger vehicles

NASA Technical Reports Server (NTRS)

Demerdash, N. A.; Lee, F. C.; Nehl, T. W.; Overton, B. P.

1980-01-01

A functional model 15 HP, 120 volt, 4-pole, 7600 r.p.m. samarium-cobalt permanent magnet type brushless dc motor-transistorized power conditioner unit was designed, fabricated and tested for specific use in propulsion of electric passenger vehicles. This new brushless motor system, including its power conditioner package, has a number of important advantages over existing systems such as reduced weight and volume, higher reliability, and potential for improvements in efficiencies. These advantages are discussed in this paper in light of the substantial test data collected during experimentation with the newly developed conditioner motor propulsion system. Details of the power conditioner design philosophy and particulars are given in the paper. Also, described here are the low level electronic design and operation in relation to the remainder of the system.
Introductory assessment of orbiting reflections for terrestrial power generation

NASA Technical Reports Server (NTRS)

Billman, K. W.; Gilbreath, W. P.; Bowen, S. W.

1977-01-01

The use of orbiting mirrors for providing energy to ground conversion stations to produce electrical power is shown to be a viable, cost effective and environmentally sound alternative to satellite solar power stations and conventional power sources. This is accomplished with the use of very light weight metal coated polymeric films as mirrors which, after deployment at 800 km, are placed in operational orbit and controlled by solar radiation pressure. Relations are developed showing the influence of a number of parameters (mirror altitude, orbit inclination, period, mirror size and number, and atmospheric effects) on the reflected insolation that may be received by a ground spot as a function of location. Some attractive alternative uses of the reflection are briefly discussed as a beneficial adjuncts to the system.
Understanding redshift space distortions in density-weighted peculiar velocity

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

Sugiyama, Naonori S.; Okumura, Teppei; Spergel, David N., E-mail: nao.s.sugiyama@gmail.com, E-mail: teppei.oku@gmail.com, E-mail: dns@astro.princeton.edu

2016-07-01

Observations of the kinetic Sunyaev-Zel'dovich (kSZ) effect measure the density-weighted velocity field, a potentially powerful cosmological probe. This paper presents an analytical method to predict the power spectrum and two-point correlation function of the density-weighted velocity in redshift space, the direct observables in kSZ surveys. We show a simple relation between the density power spectrum and the density-weighted velocity power spectrum that holds for both dark matter and halos. Using this relation, we can then extend familiar perturbation expansion techniques to the kSZ power spectrum. One of the most important features of density-weighted velocity statistics in redshift space is themore » change in sign of the cross-correlation between the density and density-weighted velocity at mildly small scales due to nonlinear redshift space distortions. Our model can explain this characteristic feature without any free parameters. As a result, our results can precisely predict the non-linear behavior of the density-weighted velocity field in redshift space up to ∼ 30 h {sup -1} Mpc for dark matter particles at the redshifts of z =0.0, 0.5, and 1.0.« less
Maintaining functional properties of shell eggs by ultrasound treatment.

PubMed

Caner, Cengiz; Yuceer, Muhammed

2015-11-01

Ultrasonic treatment is an emerging technique that could be an alternative to existing thermal processing techniques in foods. Ultrasonic treatments may also be used to extend the shelf life of egg during storage period in ambient temperature. The effectiveness of ultrasound treatment with different power levels (200 W, 300 W, 450 W) and treatment times (2 min and 5 min) was evaluated for enhancing the functional properties of eggs during storage at 24 ° C for 6 weeks. Ultrasound treatment power and treatment time had significant effects on Haugh unit, yolk index, albumen pH, dry matter, relative whipping capacity, and albumen viscosity resulting in extended shelf life. Attributes such as yolk index, Haugh unit, pH, whipping capacity, dry matter for 300 W and 450 W treatments were better than control and 200 W treatments. Longer treatment time and power showed a significant influence on functional properties. Power levels of 300 W and 450 W of ultrasound treatments had improved internal quality of fresh eggs during storage, but negative effect on shell strength. The study showed that ultrasound treatment could be an alternative and effective technique for maintaining the internal qualities of fresh eggs during long-term storage while Fourier transform near infrared spectroscopy could be used as a new tool for the assessment of freshness. © 2014 Society of Chemical Industry.
Nondestructive Examination for Nuclear Power Plant Cable Aging Management Programs

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

Glass, Samuel W.; Fifield, Leonard S.

2016-01-01

Degradation of the cable jacket, electrical insulation, and other cable components of installed cables within nuclear power plants (NPPs) is known to occur as a function of age, temperature, radiation, and other environmental factors. System tests verify cable function under normal loads; however, the concern is over cable performance under exceptional loads associated with design-basis events (DBEs). The cable’s ability to perform safely over the initial 40 year planned and licensed life has generally been demonstrated and there have been very few age-related cable failures. With greater than 1000 km of power, control, instrumentation, and other cables typically found inmore » an NPP, replacing all the cables would be a severe cost burden. Justification for life extension to 60 and 80 years requires a cable aging management program (AMP) to justify cable performance under normal operation as well as accident conditions. This paper addresses various NDE technologies that constitute the essence of an acceptable aging management program.« less
Customized dynamic splinting: orthoses that promote optimal function and recovery after radial nerve injury: a case report.

PubMed

McKee, Pat; Nguyen, Cecilia

2007-01-01

Radial nerve injury is a relatively common occurrence and recovery depends on the level of injury and extent of connective tissue damage. Orthoses (splints) are often provided to compensate for lost motor power. This article chronicles the recovery, over 27 months, of a 76-year-old woman who sustained a high radial nerve injury of her dominant arm during surgery for total shoulder replacement (Delta Reverse). Customized, low-profile dynamic splints, unlike any previously published design, were developed to address her goals for functional independence and the biological needs of the tissues. Dynamic power was provided to the wrist, fingers, and thumb by elastic cords and thin, flexible thermoplastic, without the need of an outrigger, thus avoiding the need for wire bending and cutting. At the outset, the splint was forearm-based and when wrist extension power was recovered, a hand-based splint was designed. Eventually, a circumferential hand-based thumb-stabilizing splint fulfilled most of the remaining orthotic requirements.
Structural and functional networks in complex systems with delay.

PubMed

Eguíluz, Víctor M; Pérez, Toni; Borge-Holthoefer, Javier; Arenas, Alex

2011-05-01

Functional networks of complex systems are obtained from the analysis of the temporal activity of their components, and are often used to infer their unknown underlying connectivity. We obtain the equations relating topology and function in a system of diffusively delay-coupled elements in complex networks. We solve exactly the resulting equations in motifs (directed structures of three nodes) and in directed networks. The mean-field solution for directed uncorrelated networks shows that the clusterization of the activity is dominated by the in-degree of the nodes, and that the locking frequency decreases with increasing average degree. We find that the exponent of a power law degree distribution of the structural topology γ is related to the exponent of the associated functional network as α=(2-γ)(-1) for γ<2. © 2011 American Physical Society
AIM: a comprehensive Arabidopsis interactome module database and related interologs in plants.

PubMed

Wang, Yi; Thilmony, Roger; Zhao, Yunjun; Chen, Guoping; Gu, Yong Q

2014-01-01

Systems biology analysis of protein modules is important for understanding the functional relationships between proteins in the interactome. Here, we present a comprehensive database named AIM for Arabidopsis (Arabidopsis thaliana) interactome modules. The database contains almost 250,000 modules that were generated using multiple analysis methods and integration of microarray expression data. All the modules in AIM are well annotated using multiple gene function knowledge databases. AIM provides a user-friendly interface for different types of searches and offers a powerful graphical viewer for displaying module networks linked to the enrichment annotation terms. Both interactive Venn diagram and power graph viewer are integrated into the database for easy comparison of modules. In addition, predicted interologs from other plant species (homologous proteins from different species that share a conserved interaction module) are available for each Arabidopsis module. AIM is a powerful systems biology platform for obtaining valuable insights into the function of proteins in Arabidopsis and other plants using the modules of the Arabidopsis interactome. Database URL:http://probes.pw.usda.gov/AIM Published by Oxford University Press 2014. This work is written by US Government employees and is in the public domain in the US.
Analytical time-domain Green’s functions for power-law media

PubMed Central

Kelly, James F.; McGough, Robert J.; Meerschaert, Mark M.

2008-01-01

Frequency-dependent loss and dispersion are typically modeled with a power-law attenuation coefficient, where the power-law exponent ranges from 0 to 2. To facilitate analytical solution, a fractional partial differential equation is derived that exactly describes power-law attenuation and the Szabo wave equation [“Time domain wave-equations for lossy media obeying a frequency power-law,” J. Acoust. Soc. Am. 96, 491–500 (1994)] is an approximation to this equation. This paper derives analytical time-domain Green’s functions in power-law media for exponents in this range. To construct solutions, stable law probability distributions are utilized. For exponents equal to 0, 1∕3, 1∕2, 2∕3, 3∕2, and 2, the Green’s function is expressed in terms of Dirac delta, exponential, Airy, hypergeometric, and Gaussian functions. For exponents strictly less than 1, the Green’s functions are expressed as Fox functions and are causal. For exponents greater than or equal than 1, the Green’s functions are expressed as Fox and Wright functions and are noncausal. However, numerical computations demonstrate that for observation points only one wavelength from the radiating source, the Green’s function is effectively causal for power-law exponents greater than or equal to 1. The analytical time-domain Green’s function is numerically verified against the material impulse response function, and the results demonstrate excellent agreement. PMID:19045774
Alpha power increases in right parietal cortex reflects focused internal attention

PubMed Central

Benedek, Mathias; Schickel, Rainer J.; Jauk, Emanuel; Fink, Andreas; Neubauer, Aljoscha C.

2014-01-01

This study investigated the functional significance of EEG alpha power increases, a finding that is consistently observed in various memory tasks and specifically during divergent thinking. It was previously shown that alpha power is increased when tasks are performed in mind—e.g., when bottom-up processing is prevented. This study aimed to examine the effect of task-immanent differences in bottom-up processing demands by comparing two divergent thinking tasks, one intrinsically relying on bottom-up processing (sensory-intake task) and one that is not (sensory-independence task). In both tasks, stimuli were masked in half of the trials to establish conditions of higher and lower internal processing demands. In line with the hypotheses, internal processing affected performance and led to increases in alpha power only in the sensory-intake task, whereas the sensory-independence task showed high levels of task-related alpha power in both conditions. Interestingly, conditions involving focused internal attention showed a clear lateralization with higher alpha power in parietal regions of the right hemisphere. Considering evidence from fMRI studies, right-parietal alpha power increases may correspond to a deactivation of the right temporoparietal junction, reflecting an inhibition of the ventral attention network. Inhibition of this region is thought to prevent reorienting to irrelevant stimulation during goal-driven, top-down behavior, which may serve the executive function of task shielding during demanding cognitive tasks such as idea generation and mental imagery. PMID:24561034
Generalized Fractional Derivative Anisotropic Viscoelastic Characterization.

PubMed

Hilton, Harry H

2012-01-18

Isotropic linear and nonlinear fractional derivative constitutive relations are formulated and examined in terms of many parameter generalized Kelvin models and are analytically extended to cover general anisotropic homogeneous or non-homogeneous as well as functionally graded viscoelastic material behavior. Equivalent integral constitutive relations, which are computationally more powerful, are derived from fractional differential ones and the associated anisotropic temperature-moisture-degree-of-cure shift functions and reduced times are established. Approximate Fourier transform inversions for fractional derivative relations are formulated and their accuracy is evaluated. The efficacy of integer and fractional derivative constitutive relations is compared and the preferential use of either characterization in analyzing isotropic and anisotropic real materials must be examined on a case-by-case basis. Approximate protocols for curve fitting analytical fractional derivative results to experimental data are formulated and evaluated.
Transmasculine People's Voice Function: A Review of the Currently Available Evidence.

PubMed

Azul, David; Nygren, Ulrika; Södersten, Maria; Neuschaefer-Rube, Christiane

2017-03-01

This study aims to evaluate the currently available discursive and empirical data relating to those aspects of transmasculine people's vocal situations that are not primarily gender-related, to identify restrictions to voice function that have been observed in this population, and to make suggestions for future voice research and clinical practice. We conducted a comprehensive review of the voice literature. Publications were identified by searching six electronic databases and bibliographies of relevant articles. Twenty-two publications met inclusion criteria. Discourses and empirical data were analyzed for factors and practices that impact on voice function and for indications of voice function-related problems in transmasculine people. The quality of the evidence was appraised. The extent and quality of studies investigating transmasculine people's voice function was found to be limited. There was mixed evidence to suggest that transmasculine people might experience restrictions to a range of domains of voice function, including vocal power, vocal control/stability, glottal function, pitch range/variability, vocal endurance, and voice quality. More research into the different factors and practices affecting transmasculine people's voice function that takes account of a range of parameters of voice function and considers participants' self-evaluations is needed to establish how functional voice production can be best supported in this population. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.
High Speed and High Functional Inverter Power Supplies for Plasma Generation and Control, and their Performance

NASA Astrophysics Data System (ADS)

Uesugi, Yoshihiko; Razzak, Mohammad A.; Kondo, Kenji; Kikuchi, Yusuke; Takamura, Shuichi; Imai, Takahiro; Toyoda, Mitsuhiro

The Rapid development of high power and high speed semiconductor switching devices has led to their various applications in related plasma fields. Especially, a high speed inverter power supply can be used as an RF power source instead of conventional linear amplifiers and a power supply to control the magnetic field in a fusion plasma device. In this paper, RF thermal plasma production and plasma heating experiments are described emphasis placed on using a static induction transistor inverter at a frequency range between 200 kHz and 2.5 MHz as an RF power supply. Efficient thermal plasma production is achieved experimentally by using a flexible and easily operated high power semiconductor inverter power supply. Insulated gate bipolar transistor (IGBT) inverter power supplies driven by a high speed digital signal processor are applied as tokamak joule coil and vertical coil power supplies to control plasma current waveform and plasma equilibrium. Output characteristics, such as the arbitrary bipolar waveform generation of a pulse width modulation (PWM) inverter using digital signal processor (DSP) can be successfully applied to tokamak power supplies for flexible plasma current operation and fast position control of a small tokamak.

The muon content of EAS as a function of primary energy

NASA Technical Reports Server (NTRS)

Blake, P. R.; Nash, W. F.; Saich, M. S.; Sephton, A. J.

1985-01-01

The muon content of extensive air showers (EAS) was measured over the wide primary energy range 10 to the 16th power to 10 to the 20th power eV. It is reported that the relative muon content of EAS decreases smoothly over the energy range 10 to the 17th power to 10 to the 19th power eV and concluded that the primary cosmic ray flux has a constant mass composition over this range. It is also reported that an apparent significant change in the power index occurs below 10 to the 17th power eV rho sub c (250 m) sup 0.78. Such a change indicates a significant change in primary mass composition in this range. The earlier conclusions concerning EAS of energy 10 to the 17th power eV are confirmed. Analysis of data in the 10 to the 16th power - 10 to the 17th power eV range revealed a previously overlooked selection bias in the data set. The full analysis of the complete data set in the energy range 10 to the 16th power - 10 to the 17th power ev with the selection bias eliminated is presented.
SCIMITAR: subject-carried implant monitoring inductive telemetric ambulatory reader for remote data acquisition from implanted orthopaedic prostheses.

PubMed

Hao, Shiying; Gorjon, Jose; Taylor, Stephen

2014-03-01

This work describes the functions of the external, portable part of a telemetry system for powering and interrogating implantable electrical devices built within orthopaedic implants for real-time data acquisition of strain, load, temperature, humidity and other relevant data (e.g. from inertial sensors). The system contains a battery powered inductive energiser and demodulator to remotely power the implant electronics and demodulate the signals transmitted from the implanted device. Due to the housing of the internal coil, sufficient inductive coupling is obtained between the external and internal tuned circuits to enable simultaneous power and data transmission over the same inductive link. The actual performance of this system when used with one specific implant was studied, and some correspondence made to the relevant theory. Performance factors relating to both power efficiency and data reconstruction were identified. Copyright © 2013 IPEM. Published by Elsevier Ltd. All rights reserved.
Measurement of total ultrasonic power using thermal expansion and change in buoyancy of an absorbing target

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

Dubey, P. K., E-mail: premkdubey@gmail.com; Kumar, Yudhisther; Gupta, Reeta

2014-05-15

The Radiation Force Balance (RFB) technique is well established and most widely used for the measurement of total ultrasonic power radiated by ultrasonic transducer. The technique is used as a primary standard for calibration of ultrasonic transducers with relatively fair uncertainty in the low power (below 1 W) regime. In this technique, uncertainty comparatively increases in the range of few watts wherein the effects such as thermal heating of the target, cavitations, and acoustic streaming dominate. In addition, error in the measurement of ultrasonic power is also caused due to movement of absorber at relatively high radiated force which occursmore » at high power level. In this article a new technique is proposed which does not measure the balance output during transducer energized state as done in RFB. It utilizes the change in buoyancy of the absorbing target due to local thermal heating. The linear thermal expansion of the target changes the apparent mass in water due to buoyancy change. This forms the basis for the measurement of ultrasonic power particularly in watts range. The proposed method comparatively reduces uncertainty caused by various ultrasonic effects that occur at high power such as overshoot due to momentum of target at higher radiated force. The functionality of the technique has been tested and compared with the existing internationally recommended RFB technique.« less
Measurement of total ultrasonic power using thermal expansion and change in buoyancy of an absorbing target

NASA Astrophysics Data System (ADS)

Dubey, P. K.; Kumar, Yudhisther; Gupta, Reeta; Jain, Anshul; Gohiya, Chandrashekhar

2014-05-01

The Radiation Force Balance (RFB) technique is well established and most widely used for the measurement of total ultrasonic power radiated by ultrasonic transducer. The technique is used as a primary standard for calibration of ultrasonic transducers with relatively fair uncertainty in the low power (below 1 W) regime. In this technique, uncertainty comparatively increases in the range of few watts wherein the effects such as thermal heating of the target, cavitations, and acoustic streaming dominate. In addition, error in the measurement of ultrasonic power is also caused due to movement of absorber at relatively high radiated force which occurs at high power level. In this article a new technique is proposed which does not measure the balance output during transducer energized state as done in RFB. It utilizes the change in buoyancy of the absorbing target due to local thermal heating. The linear thermal expansion of the target changes the apparent mass in water due to buoyancy change. This forms the basis for the measurement of ultrasonic power particularly in watts range. The proposed method comparatively reduces uncertainty caused by various ultrasonic effects that occur at high power such as overshoot due to momentum of target at higher radiated force. The functionality of the technique has been tested and compared with the existing internationally recommended RFB technique.
Health related quality of life in parents of six to eight year old children with Down syndrome.

PubMed

Marchal, Jan Pieter; Maurice-Stam, Heleen; Hatzmann, Janneke; van Trotsenburg, A S Paul; Grootenhuis, Martha A

2013-11-01

Raising a child with Down syndrome (DS) has been found to be associated with lowered health related quality of life (HRQoL) in the domains cognitive functioning, social functioning, daily activities and vitality. We aimed to explore which socio-demographics, child functioning and psychosocial variables were related to these HRQoL domains in parents of children with DS. Parents of 98 children with DS completed the TNO-AZL adult quality of life questionnaire (TAAQOL) and a questionnaire assessing socio-demographic, child functioning and psychosocial predictors. Using multiple linear regression analyses for each category of predictors, we selected relevant predictors for the final models. The final multiple linear regression models revealed that cognitive functioning was best predicted by the sleep of the child (β=.29, p<.01) and by the parent having given up a hobby (β=-.29, p<.01), social functioning by the quality of the partner relation (β=.34, p<.001), daily activities by the parent having to care for an ill friend or family member (β=-.31, p<.01), and vitality by the parent having enough personal time (β=.32, p<.01). Overall, psychosocial variables rather than socio-demographics or child functioning showed most consistent and powerful relations to the HRQoL domains of cognitive functioning, social functioning, daily activities and vitality. These psychosocial variables mainly related to social support and time pressure. Systematic screening of parents to detect problems timely, and interventions targeting the supportive network and the demands in time are recommended. Copyright © 2013 Elsevier Ltd. All rights reserved.
Downflow dryout in a heated ribbed vertical annulus with a cosine power profile (Results from test series ECS-2, WSR, and ECS-2cE)

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

Larson, T.K.; Anderson, J.L.; Condie, K.G.

Experiments designed to investigate surface dryout in a heated, ribbed annulus test section simulating one of the annular coolant channels of a Savannah River Plant production reactor Mark 22 fuel assembly have been conducted at the Idaho National Engineering Laboratory. The inner surface of the annulus was constructed of aluminum and was electrically heated to provide an axial cosine power profile and a flat azimuthal power shape. Data presented in this report are from the ECS-2, WSR, and ECS-2cE series of tests. These experiments were conducted to examine the onset of wall thermal excursion for a range of flow, inletmore » fluid temperature, and annulus outlet pressure. Hydraulic boundary conditions on the test section represent flowrates (0.1--1.4 1/s), inlet fluid temperatures (293--345 K), and outlet pressures (-18--139.7 cm of water relative to the bottom of the heated length (61--200 cm of water relative to the bottom of the lower plenum)) expected to occur during the Emergency Coolant System (ECS) phase of postulated Loss-of-Coolant Accident in a production reactor. The onset of thermal excursion based on the present data is consistent with data gathered in test rigs with flat axial power profiles. The data indicate that wall dryout is primarily a function of liquid superficial velocity. Air entrainment rate was observed to be a strong function of the boundary conditions (primarily flowrate and liquid temperature), but had a minor effect on the power at the onset of thermal excursion for the range of conditions examined. 14 refs., 33 figs., 13 tabs.« less
Virasoro constraints and polynomial recursion for the linear Hodge integrals

NASA Astrophysics Data System (ADS)

Guo, Shuai; Wang, Gehao

2017-04-01

The Hodge tau-function is a generating function for the linear Hodge integrals. It is also a tau-function of the KP hierarchy. In this paper, we first present the Virasoro constraints for the Hodge tau-function in the explicit form of the Virasoro equations. The expression of our Virasoro constraints is simply a linear combination of the Virasoro operators, where the coefficients are restored from a power series for the Lambert W function. Then, using this result, we deduce a simple version of the Virasoro constraints for the linear Hodge partition function, where the coefficients are restored from the Gamma function. Finally, we establish the equivalence relation between the Virasoro constraints and polynomial recursion formula for the linear Hodge integrals.
New form of the exact NSVZ β-function: the three-loop verification for terms containing Yukawa couplings

NASA Astrophysics Data System (ADS)

Kazantsev, A. E.; Shakhmanov, V. Yu.; Stepanyantz, K. V.

2018-04-01

We investigate a recently proposed new form of the exact NSVZ β-function, which relates the β-function to the anomalous dimensions of the quantum gauge superfield, of the Faddeev-Popov ghosts, and of the chiral matter superfields. Namely, for the general renormalizable N = 1 supersymmetric gauge theory, regularized by higher covariant derivatives, the sum of all three-loop contributions to the β-function containing the Yukawa couplings is compared with the corresponding two-loop contributions to the anomalous dimensions of the quantum superfields. It is demonstrated that for the considered terms both new and original forms of the NSVZ relation are valid independently of the subtraction scheme if the renormalization group functions are defined in terms of the bare couplings. This result is obtained from the equality relating the loop integrals, which, in turn, follows from the factorization of the integrals for the β-function into integrals of double total derivatives. For the renormalization group functions defined in terms of the renormalized couplings we verify that the NSVZ scheme is obtained with the higher covariant derivative regularization supplemented by the subtraction scheme in which only powers of ln Λ /μ are included into the renormalization constants.
Engines with ideal efficiency and nonzero power for sublinear transport laws

NASA Astrophysics Data System (ADS)

Koning, Jesper; Indekeu, Joseph O.

2016-11-01

It is known that an engine with ideal efficiency (η = 1 for a chemical engine and e = eCarnot for a thermal one) has zero power because a reversible cycle takes an infinite time. However, at least from a theoretical point of view, it is possible to conceive (irreversible) engines with nonzero power that can reach ideal efficiency. Here this is achieved by replacing the usual linear transport law by a sublinear one and taking the step-function limit for the particle current (chemical engine) or heat current (thermal engine) versus the applied force. It is shown that in taking this limit exact thermodynamic inequalities relating the currents to the entropy production are not violated.
Highly Efficient Moisture-Triggered Nanogenerator Based on Graphene Quantum Dots.

PubMed

Huang, Yaxin; Cheng, Huhu; Shi, Gaoquan; Qu, Liangti

2017-11-08

A high-performance moisture triggered nanogenerator is fabricated by using graphene quantum dots (GQDs) as the active material. GQDs are prepared by direct oxidation and etching of natural graphite powder, which have small sizes of 2-5 nm and abundant oxygen-containing functional groups. After the treatment by electrochemical polarization, the GQDs-based moisture triggered nanogenerator can deliver a high voltage up to 0.27 V under 70% relative humidity variation, and a power density of 1.86 mW cm -2 with an optimized load resistor. The latter value is much higher than the moisture-electric power generators reported previously. The GQD moisture triggered nanogenerator is promising for self-power electronics and miniature sensors.
Profitability primer: a guide to profitability analysis in the electric power industry

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

Woo, C.K.; Lloyd-Zannetti, D.; Martin, J.

1996-06-01

As the electric power industry is opened to forces of competition, increased attention must be focused to develop products and services that deliver good value to customers and to identify customer segments that are profitable to serve. This primer introduces the concept of profitability analysis and its application to the electric power industry. The primer recognizes that some segments of the business will remain monopolistic and subject to regulations, while other segments will become competitive. The primer also recognizes that customer profitability is critically dependent on a host of related issues such as how internal costs are allocated to variousmore » functions and how revenues are collected and allocated.« less
Equivalent refractive-index structure constant of non-Kolmogorov turbulence.

PubMed

Li, Yujie; Zhu, Wenyue; Wu, Xiaoqing; Rao, Ruizhong

2015-09-07

The relationship between the non-Kolmogorov refractive-index structure constant and the Kolmogorov refractive-index structure constant is derived by using the refractive-index structure function and the variance of refractive-index fluctuations. It shows that the non-Kolmogorov structure constant is proportional to the Kolmogorov structure constant and the scaling factor depends on the outer scale and the spectral power law. For a fixed Kolmogorov structure constant, the non-Kolmogorov structure constant increases with a increasing outer scale for the power law less than 11/3, the trend is opposite for the power law greater than 11/3. This equivalent relation provides a way of obtaining the non-Kolmogorov structure constant by using the Kolmogorov structure constant.
Design criteria for noncoherent Gaussian channels with MFSK signaling and coding

NASA Technical Reports Server (NTRS)

Butman, S. A.; Levitt, B. K.; Bar-David, I.; Lyon, R. F.; Klass, M. J.

1976-01-01

This paper presents data and criteria to assess and guide the design of modems for coded noncoherent communication systems subject to practical system constraints of power, bandwidth, noise spectral density, coherence time, and number of orthogonal signals M. Three basic receiver types are analyzed for the noncoherent multifrequency-shift keying (MFSK) additive white Gaussian noise channel: hard decision, unquantized (optimum), and quantized (soft decision). Channel capacity and computational cutoff rate are computed for each type and presented as functions of the predetection signal-to-noise ratio and the number of orthogonal signals. This relates the channel constraints of power, bandwidth, coherence time, and noise power to the optimum choice of signal duration and signal number.
Whole-body angular momentum during stair walking using passive and powered lower-limb prostheses.

PubMed

Pickle, Nathaniel T; Wilken, Jason M; Aldridge, Jennifer M; Neptune, Richard R; Silverman, Anne K

2014-10-17

Individuals with a unilateral transtibial amputation have a greater risk of falling compared to able-bodied individuals, and falling on stairs can lead to serious injuries. Individuals with transtibial amputations have lost ankle plantarflexor muscle function, which is critical for regulating whole-body angular momentum to maintain dynamic balance. Recently, powered prostheses have been designed to provide active ankle power generation with the goal of restoring biological ankle function. However, the effects of using a powered prosthesis on the regulation of whole-body angular momentum are unknown. The purpose of this study was to use angular momentum to evaluate dynamic balance in individuals with a transtibial amputation using powered and passive prostheses relative to able-bodied individuals during stair ascent and descent. Ground reaction forces, external moment arms, and joint powers were also investigated to interpret the angular momentum results. A key result was that individuals with an amputation had a larger range of sagittal-plane angular momentum during prosthetic limb stance compared to able-bodied individuals during stair ascent. There were no significant differences in the frontal, transverse, or sagittal-plane ranges of angular momentum or maximum magnitude of the angular momentum vector between the passive and powered prostheses during stair ascent or descent. These results indicate that individuals with an amputation have altered angular momentum trajectories during stair walking compared to able-bodied individuals, which may contribute to an increased fall risk. The results also suggest that a powered prosthesis provides no distinct advantage over a passive prosthesis in maintaining dynamic balance during stair walking. Copyright © 2014 Elsevier Ltd. All rights reserved.
New Probe of Departures from General Relativity Using Minkowski Functionals.

PubMed

Fang, Wenjuan; Li, Baojiu; Zhao, Gong-Bo

2017-05-05

The morphological properties of the large scale structure of the Universe can be fully described by four Minkowski functionals (MFs), which provide important complementary information to other statistical observables such as the widely used 2-point statistics in configuration and Fourier spaces. In this work, for the first time, we present the differences in the morphology of the large scale structure caused by modifications to general relativity (to address the cosmic acceleration problem), by measuring the MFs from N-body simulations of modified gravity and general relativity. We find strong statistical power when using the MFs to constrain modified theories of gravity: with a galaxy survey that has survey volume ∼0.125(h^{-1} Gpc)^{3} and galaxy number density ∼1/(h^{-1} Mpc)^{3}, the two normal-branch Dvali-Gabadadze-Porrati models and the F5 f(R) model that we simulated can be discriminated from the ΛCDM model at a significance level ≳5σ with an individual MF measurement. Therefore, the MF of the large scale structure is potentially a powerful probe of gravity, and its application to real data deserves active exploration.
[The influence of high-tone power therapy on the functional status of patients with multiple sclerosis].

PubMed

Kubsik, Anna; Klimkiewicz, Paulina; Klimkiewicz, Robert; Jankowska, Katarzyna; Jankowska, Agnieszka; Woldańska-Okońska, Marta

2014-07-01

Multiple sclerosis is a chronic, inflammatory, demyelinating disease of the central nervous system, which is characterized by diverse symptomatology. Most often affects people at a young age gradually leading to their disability. Looking for new therapies to alleviate neurological deficits caused by the disease. One of the alternative methods of therapy is high - tone power therapy. The article is a comparison of high-tone power therapy and kinesis in improving patients with multiple sclerosis. The aim of this study was to evaluate the effectiveness of high-tone power therapy and exercises in kinesis on the functional status of patients with multiple sclerosis. The study involved 20 patients with multiple sclerosis, both sexes, treated at the Department of Rehabilitation and Physical Medicine in Lodz. Patients were randomly divided into two groups studied. In group high-tone power therapy applied for 60 minutes, while in group II were used exercises for kinesis. Treatment time for both groups of patients was 15 days. To assess the functional status scale was used: Expanded Disability Status Scale of Kurtzke (EDSS), as well as by Barthel ADL Index. Assessment of quality of life were made using MSQOL Questionnaire-54. For the evaluation of gait and balance using Tinetti scale, and pain VAS rated, and Laitinen. Changes in muscle tone was assessed on the basis of the Ashworth scale. Both group I and II improved on scales conducted before and after therapy. In group I, in which the applied high-tone power therapy, reported statistically significant results in 9 out of 10 tested parameters, while in group II, which was used in the exercises in kinesis an improvement in 6 out of 10 tested parameters. Correlating the results of both the test groups in relation to each other did not show statistically significant differences. High-Tone Power Therapy beneficial effect on the functional status of patients with multiple sclerosis. Obtaining results in terms of number of tested parameters allows for the use of this therapy in the comprehensive improvement of patients with multiple sclerosis. Exercises from the scheme kinesis favorable impact on the functional status of patients with MS and are essential in the rehabilitation of these patients. In any group, no adverse effects were observed.
18 CFR 367.83 - Training costs.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Training costs. 367.83... Expense Instructions § 367.83 Training costs. When it is necessary that employees be trained to... functional accounts currently as they are incurred. However, when the training costs involved relate to...
Conceptualization and Treatment for Vietnam Veterans Experiencing Posttraumatic Stress Disorder.

ERIC Educational Resources Information Center

Lawson, David M.

1995-01-01

Presents model that can be employed in working with Vietnam veterans experiencing posttraumatic stress disorder (PTSD). Incorporates cognitive, behavioral, and interactional components and focuses on helping veterans to identify schemas that are related to five areas of psychological and interpersonal functioning: safety, trust, power, esteem, and…
The Increased Pluralism and Politicization of Public Education--Coping with Conflict.

ERIC Educational Resources Information Center

Coleman, Peter

Power, or influence, in educational governance is increasingly becoming diffused. Everyone in education now feels relatively powerless. A political model of decision-making, emphasizing consultation with representatives of interest groups is now appropriate. In this model, the school board functions as "meta-mediator." This modifies the…
The shadow price of substitutable sulfur in the US electric power plant: a distance function approach.

PubMed

Lee, Myunghun

2005-10-01

Given restrictions on sulfur dioxide emissions, a feasible long-run response could involve either an investment in improving boiler fuel-efficiency or a shift to a production process that is effective in removing sulfur dioxide. To allow for the possibility of substitution between sulfur and productive capital, we measure the shadow price of sulfur dioxide as the opportunity cost of lowering sulfur emissions in terms of forgone capital. The input distance function is estimated with data from 51 coal-fired US power units operating between 1977 and 1986. The indirect Morishima elasticities of substitution indicate that the substitutability of capital for sulfur is relatively high. The overall weighted average estimate of the shadow price of sulfur is -0.076 dollars per pound in constant 1976 dollars.

Physical functions, health-related outcomes, nutritional status, and blood markers in community-dwelling cancer survivors aged 75 years and older.

PubMed

Ihira, Hikaru; Mizumoto, Atsushi; Makino, Keitarou; Yasuda, Keisuke; Yoko, Yoko; Saitoh, Shigeyuki; Ohnishi, Hirofumi; Furuna, Taketo

2014-01-01

A cancer survivor is defined as anyone who has been diagnosed with cancer, from the time of diagnosis through the rest of their life. The purpose of this study was to examine whether physical functions, health-related outcomes, nutritional status and blood markers in community-dwelling cancer survivors aged 75 years and older are different from those who do not have cancer Two hundred seventy-five participants were asked by physicians, nurses, and physical therapists, questions regarding cancer history in a face-to-face interview. Data were collected for demographic information, physical functions, such as handgrip strength, knee extension power, abdominal muscle strength, static standing balance, walking speed and the timed-up-and-go test, health-related outcomes, nutritional status, and blood markers. The measured parameters of survivor diagnosed with cancer were compared with those without a history of cancer. Thirty-seven older adults were previously diagnosed with cancer. Female cancer survivors had lower knee extension power (p<0.05), abdominal muscle strength (p<0.05), walking speed (p<0.05), timed-up-and-go test score (p<0.05), and time to spend on walking per day (p<0.05) than older women without a history of cancer. In men, none of the measured parameters were significantly different between cancer survivors and older men with no history of cancer. The present study shows that partial physical function of women cancer survivors aged 75 years and older differs from that in women with no history of cancer.
Test Protocols for Advanced Inverter Interoperability Functions – Main Document

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

Johnson, Jay Dean; Gonzalez, Sigifredo; Ralph, Mark E.

2013-11-01

Distributed energy resources (DER) such as photovoltaic (PV) systems, when deployed in a large scale, are capable of influencing significantly the operation of power systems. Looking to the future, stakeholders are working on standards to make it possible to manage the potentially complex interactions between DER and the power system. In 2009, the Electric Power Research Institute (EPRI), Sandia National Laboratories (SNL) with the U.S. Department of Energy (DOE), and the Solar Electric Power Association (SEPA) initiated a large industry collaborative to identify and standardize definitions for a set of DER grid support functions. While the initial effort concentrated onmore » grid-tied PV inverters and energy storage systems, the concepts have applicability to all DER. A partial product of this on-going effort is a reference definitions document (IEC TR 61850-90-7, Object models for power converters in distributed energy resources (DER) systems) that has become a basis for expansion of related International Electrotechnical Commission (IEC) standards, and is supported by US National Institute of Standards and Technology (NIST) Smart Grid Interoperability Panel (SGIP). Some industry-led organizations advancing communications protocols have also embraced this work. As standards continue to evolve, it is necessary to develop test protocols to independently verify that the inverters are properly executing the advanced functions. Interoperability is assured by establishing common definitions for the functions and a method to test compliance with operational requirements. This document describes test protocols developed by SNL to evaluate the electrical performance and operational capabilities of PV inverters and energy storage, as described in IEC TR 61850-90-7. While many of these functions are not currently required by existing grid codes or may not be widely available commercially, the industry is rapidly moving in that direction. Interoperability issues are already apparent as some of these inverter capabilities are being incorporated in large demonstration and commercial projects. The test protocols are intended to be used to verify acceptable performance of inverters within the standard framework described in IEC TR 61850-90-7. These test protocols, as they are refined and validated over time, can become precursors for future certification test procedures for DER advanced grid support functions.« less
Test Protocols for Advanced Inverter Interoperability Functions - Appendices

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

Johnson, Jay Dean; Gonzalez, Sigifredo; Ralph, Mark E.

2013-11-01

Distributed energy resources (DER) such as photovoltaic (PV) systems, when deployed in a large scale, are capable of influencing significantly the operation of power systems. Looking to the future, stakeholders are working on standards to make it possible to manage the potentially complex interactions between DER and the power system. In 2009, the Electric Power Research Institute (EPRI), Sandia National Laboratories (SNL) with the U.S. Department of Energy (DOE), and the Solar Electric Power Association (SEPA) initiated a large industry collaborative to identify and standardize definitions for a set of DER grid support functions. While the initial effort concentrated onmore » grid-tied PV inverters and energy storage systems, the concepts have applicability to all DER. A partial product of this on-going effort is a reference definitions document (IEC TR 61850-90-7, Object models for power converters in distributed energy resources (DER) systems) that has become a basis for expansion of related International Electrotechnical Commission (IEC) standards, and is supported by US National Institute of Standards and Technology (NIST) Smart Grid Interoperability Panel (SGIP). Some industry-led organizations advancing communications protocols have also embraced this work. As standards continue to evolve, it is necessary to develop test protocols to independently verify that the inverters are properly executing the advanced functions. Interoperability is assured by establishing common definitions for the functions and a method to test compliance with operational requirements. This document describes test protocols developed by SNL to evaluate the electrical performance and operational capabilities of PV inverters and energy storage, as described in IEC TR 61850-90-7. While many of these functions are not now required by existing grid codes or may not be widely available commercially, the industry is rapidly moving in that direction. Interoperability issues are already apparent as some of these inverter capabilities are being incorporated in large demonstration and commercial projects. The test protocols are intended to be used to verify acceptable performance of inverters within the standard framework described in IEC TR 61850-90-7. These test protocols, as they are refined and validated over time, can become precursors for future certification test procedures for DER advanced grid support functions.« less
Power-law scaling for macroscopic entropy and microscopic complexity: Evidence from human movement and posture

NASA Astrophysics Data System (ADS)

Hong, S. Lee; Bodfish, James W.; Newell, Karl M.

2006-03-01

We investigated the relationship between macroscopic entropy and microscopic complexity of the dynamics of body rocking and sitting still across adults with stereotyped movement disorder and mental retardation (profound and severe) against controls matched for age, height, and weight. This analysis was performed through the examination of center of pressure (COP) motion on the mediolateral (side-to-side) and anteroposterior (fore-aft) dimensions and the entropy of the relative phase between the two dimensions of motion. Intentional body rocking and stereotypical body rocking possessed similar slopes for their respective frequency spectra, but differences were revealed during maintenance of sitting postures. The dynamics of sitting in the control group produced lower spectral slopes and higher complexity (approximate entropy). In the controls, the higher complexity found on each dimension of motion was related to a weaker coupling between dimensions. Information entropy of the relative phase between the two dimensions of COP motion and irregularity (complexity) of their respective motions fitted a power-law function, revealing a relationship between macroscopic entropy and microscopic complexity across both groups and behaviors. This power-law relation affords the postulation that the organization of movement and posture dynamics occurs as a fractal process.
RF-powered BIONs for stimulation and sensing.

PubMed

Loeb, G E; Richmond, F J R; Singh, J; Peck, R A; Tan, W; Zou, Q; Sachs, N

2004-01-01

Virtually all bodily functions are controlled by electrical signals in nerves and muscles. Electrical stimulation can restore missing signals but this has been difficult to achieve practically because of limitations in the bioelectric interfaces. Wireless, injectable microdevices are versatile, robust and relatively inexpensive to implant in a variety of sites and applications. Several variants are now in clinical use or under development to perform stimulation and/or sensing functions and to operate autonomously or with continuous coordination and feedback control.
Impaired coupling of local and global functional feedbacks underlies abnormal synchronization and negative symptoms of schizophrenia.

PubMed

Noh, Kyungchul; Shin, Kyung Soon; Shin, Dongkwan; Hwang, Jae Yeon; Kim, June Sic; Jang, Joon Hwan; Chung, Chun Kee; Kwon, Jun Soo; Cho, Kwang-Hyun

2013-04-10

Abnormal synchronization of brain oscillations is found to be associated with various core symptoms of schizophrenia. However, the underlying mechanism of this association remains yet to be elucidated. In this study, we found that coupled local and global feedback (CLGF) circuits in the cortical functional network are related to the abnormal synchronization and also correlated to the negative symptom of schizophrenia. Analysis of the magnetoencephalography data obtained from patients with chronic schizophrenia during rest revealed an increase in beta band synchronization and a reduction in gamma band power compared to healthy controls. Using a feedback identification method based on non-causal impulse responses, we constructed functional feedback networks and found that CLGF circuits were significantly reduced in schizophrenia. From computational analysis on the basis of the Wilson-Cowan model, we unraveled that the CLGF circuits are critically involved in the abnormal synchronization and the dynamical switching between beta and gamma bands power in schizophrenia. Moreover, we found that the abundance of CLGF circuits was negatively correlated with the development of negative symptoms of schizophrenia, suggesting that the negative symptom is closely related to the impairment of this circuit. Our study implicates that patients with schizophrenia might have the impaired coupling of inter- and intra-regional functional feedbacks and that the CLGF circuit might serve as a critical bridge between abnormal synchronization and the negative symptoms of schizophrenia.
Characteristics of random inlet pressure fluctuations during flights of F-111A airplane

NASA Technical Reports Server (NTRS)

Costakis, W. G.

1977-01-01

Compressor face dynamic total pressures from four F-111 flights were analyzed. Statistics of the nonstationary data were investigated by analyzing the data in a quasi-stationary manner. Changes in the character of the dynamic signal are investigated as functions of flight conditions, time in flight, and location at the compressor face. The results, which are presented in the form of rms values, histograms, and power spectrum plots, show that the shape of the power spectra remains relatively flat while the histograms have an approximate normal distribution.
Relative differences in strength and power from slow to fast isokinetic velocities may reflect dynapenia.

PubMed

Jenkins, Nathaniel D M; Housh, Terry J; Palmer, Ty B; Cochrane, Kristen C; Bergstrom, Haley C; Johnson, Glen O; Schmidt, Richard J; Cramer, Joel T

2015-07-01

We compared absolute and normalized values for peak torque (PT), mean power (MP), rate of velocity development, and electromyography (EMG) amplitude during maximal isometric and concentric isokinetic leg extension muscle actions, as well as the %decrease in PT and %increase in MP from 1.05 to 3.14 rad·s(-1) in younger versus older men. Measurements were performed twice for reliability. Isokinetic measurements were normalized to the isometric muscle actions. Absolute isometric PT, isokinetic PT and MP, and EMG amplitudes at 1.05 and 3.14 rad·s(-1) were greater in the younger men, although normalizing to isometric PT eliminated the age differences. The older men exhibited greater %decrease in PT (37.2% vs. 31.3%) and lower %increase in MP (87.6% vs. 126.4%) regardless of normalization. Normalization eliminated absolute differences in isokinetic strength and power, but the relative differences from slow to fast velocities may reflect dynapenia characterized by age-related decreases in fast-twitch fiber function. © 2014 Wiley Periodicals, Inc.
The dependence of divertor power sharing on magnetic flux balance in near double-null configurations on Alcator C-Mod

NASA Astrophysics Data System (ADS)

Brunner, D.; Kuang, A. Q.; LaBombard, B.; Terry, J. L.

2018-07-01

Management of power exhaust will be a crucial task for tokamak fusion reactors. Reactor concepts are often proposed with double-null divertors, i.e. having two magnetic separatrices in an up-down symmetric configuration. This arrangement is potentially advantageous since the majority of the tokamak exhaust power tends to flow to the outer pair of divertor legs at large major radius, where the geometry is favorable for spreading the heat over a large surface area and there is more room for advanced divertor configurations. Despite the importance, there have been relatively few studies of divertor power sharing in near double null configurations and no studies at the poloidal magnetic fields and scrape-off layer power widths anticipated for a reactor. Motivated by this need we have undertaken a systematic study on Alcator C-Mod, examining the effect of magnetic flux balance on the power sharing among the four divertor legs in near double-null plasmas. Ohmic L-modes at three values of plasma current and ICRF-heated enhanced D-alpha (EDA) H-modes and I-modes at a single value of plasma current are explored, producing poloidal magnetic fields of 0.42, 0.62 and 0.85 Tesla. For Ohmic L-modes and ICRF-heated EDA H-modes, we find that the point of equal power sharing between upper and lower divertors occurs remarkably close to a balanced double null. Power sharing amongst the outer (upper versus lower) and inner (upper versus lower) pairs of divertors can be described in terms of a logistic function of magnetic flux balance, consistent with heat flux mapping along magnetic field lines to the outer midplane. Power sharing between inner and outer legs is found to follow a Gaussian-like function of magnetic flux balance with non-zero power to the inner divertors at double null. The overall behavior of H-modes operated near double null and for I-modes operating to within one heat flux e-folding of double null are found similar to Ohmic L-modes, with a significant reduction of power on the inner divertor legs. The results are encapsulated in terms of empirically-informed analytic functions of magnetic flux balance. When combined with magnetic equilibrium control system specifications, these relationships can be used to specify the power flux handling requirements for each of the four divertor target plates.
Spinal cord injury (SCI) rehabilitation: systematic analysis of communication from the biopsychosocial perspective.

PubMed

Hartley, Naomi A

2015-07-02

Communication is powerful predictor of health-related quality of life and overall well-being, yet its role in promoting rehabilitation outcomes in spinal cord injury (SCI) is rarely mentioned. This article systematically analyzes and synthesizes literature from multiple disciplines according to a biopsychosocial perspective, providing an evidence base for clinical practice and clear direction for future research. Systematic literature review and analysis, incorporating mapping to International Classification of Functioning, Disability and Health (ICF) codes. In total 4338 entries were retrieved from CINAHL, PsychInfo, Medline, PubMed and SpeechBite databases for the period 1990-2014. A total of 115 treatment and observational studies (quantitative and qualitative) detailed aspects of communication according to structure, function, activity, participation and environmental factors; evident of the complex interactions between communicative function with daily living after SCI. Communication is a relative strength in SCI, key to empowerment, independence, social interaction, and well-being, yet its potential to enhance SCI rehabilitation outcomes remains largely underexplored and untapped. Through elucidating interactions between communication and functioning, the adapted ICF framework affords clinicians and researchers insight into areas of intervention most likely to result in widespread gains. Conscious consideration should be given to the role of communication, within an integrative, strengths-based, multidisciplinary approach to clinical practice and future research. Implications for Rehabilitation Communication fosters empowerment, independence and greater participation in life roles; recognized as a powerful predictor of health-related quality of life and overall well-being. The ICF framework elucidates influences to communicative function, and components which are influenced by communication, providing valuable insight for clinicians and researchers. Therapeutic and research endeavors guided by existing ICF core sets are at risk of failing to consider communication, thereby limiting rehabilitation outcomes. Tapping the potential of communication as a relative strength within SCI rehabilitation holds considerable promise, within integrative, strengths-based, multidisciplinary approaches to clinical practice and future research.
Concurrent relations among cigarette smoking status, resting heart rate variability, and erectile response.

PubMed

Harte, Christopher B

2014-05-01

Heart rate variability (HRV) is a marker of sympathovagal balance; it has been implicated in erectile function and is also altered by tobacco use. Furthermore, smoking and erectile health are strongly related, given that smokers are at increased risk for erectile dysfunction. Few studies have explored the interrelationships between smoking, HRV, and erectile function concurrently. The aim of this study was to examine potential mechanisms underlying tobacco's effects on penile hemodynamics by exploring the mediating role of HRV. The sample comprised 119 men (smokers = 64; nonsmokers = 55) (mean age 28.90 years; standard deviation (SD) 11.68; range 18-58) selected from the control conditions of three previously published experiments. Participants were free from a history of cardiovascular disease, myocardial infarct, and/or cardiac/cardiovascular medication use. During a laboratory visit, self-report, anthropometric, cardiovascular, and electrocardiographic data were assessed, as well as sexual arousal responses elicited from viewing an erotic film. Objective sexual arousal indices (circumferential change via penile plethysmography), self-reported erectile function (per the erectile function domain score of the International Index of Erectile Function [IIEF-EF]), and time- (SD of beat-to-beat intervals) and frequency-domain parameters of HRV (ratio of low-frequency [LF] power to high-frequency [HF] power [LF/HF ratio]) were assessed. Being a current long-term cigarette smoker was associated with dysregulated sympathovagal balance (higher LF/HF ratios, indicative of sympathetic nervous system dominance), which in turn showed inverse relations with magnitude of erectile tumescence. HRV did not mediate relations between tobacco use and either IIEF-EF scores or resting penile circumference. Findings suggest that dysfunctional cardiac autonomic tone may be an underlying mechanism by which tobacco exerts its deleterious effects on erectile health. Further research is necessary to determine whether this relationship is mechanistic in nature, or whether it is better explained by other health factors. © 2014 International Society for Sexual Medicine.
Estrogen-Related Receptor α (ERRα) and ERRγ Are Essential Coordinators of Cardiac Metabolism and Function

PubMed Central

Wang, Ting; McDonald, Caitlin; Petrenko, Nataliya B.; Leblanc, Mathias; Wang, Tao; Giguere, Vincent; Evans, Ronald M.; Patel, Vickas V.

2015-01-01

Almost all cellular functions are powered by a continuous energy supply derived from cellular metabolism. However, it is little understood how cellular energy production is coordinated with diverse energy-consuming cellular functions. Here, using the cardiac muscle system, we demonstrate that nuclear receptors estrogen-related receptor α (ERRα) and ERRγ are essential transcriptional coordinators of cardiac energy production and consumption. On the one hand, ERRα and ERRγ together are vital for intact cardiomyocyte metabolism by directly controlling expression of genes important for mitochondrial functions and dynamics. On the other hand, ERRα and ERRγ influence major cardiomyocyte energy consumption functions through direct transcriptional regulation of key contraction, calcium homeostasis, and conduction genes. Mice lacking both ERRα and cardiac ERRγ develop severe bradycardia, lethal cardiomyopathy, and heart failure featuring metabolic, contractile, and conduction dysfunctions. These results illustrate that the ERR transcriptional pathway is essential to couple cellular energy metabolism with energy consumption processes in order to maintain normal cardiac function. PMID:25624346
Optimal Output of Distributed Generation Based On Complex Power Increment

NASA Astrophysics Data System (ADS)

Wu, D.; Bao, H.

2017-12-01

In order to meet the growing demand for electricity and improve the cleanliness of power generation, new energy generation, represented by wind power generation, photovoltaic power generation, etc has been widely used. The new energy power generation access to distribution network in the form of distributed generation, consumed by local load. However, with the increase of the scale of distribution generation access to the network, the optimization of its power output is becoming more and more prominent, which needs further study. Classical optimization methods often use extended sensitivity method to obtain the relationship between different power generators, but ignore the coupling parameter between nodes makes the results are not accurate; heuristic algorithm also has defects such as slow calculation speed, uncertain outcomes. This article proposes a method called complex power increment, the essence of this method is the analysis of the power grid under steady power flow. After analyzing the results we can obtain the complex scaling function equation between the power supplies, the coefficient of the equation is based on the impedance parameter of the network, so the description of the relation of variables to the coefficients is more precise Thus, the method can accurately describe the power increment relationship, and can obtain the power optimization scheme more accurately and quickly than the extended sensitivity method and heuristic method.
A review of acoustic power transfer for bio-medical implants

NASA Astrophysics Data System (ADS)

Basaeri, Hamid; Christensen, David B.; Roundy, Shad

2016-12-01

Bio-implantable devices have been used to perform therapeutic functions such as drug delivery or diagnostic monitoring of physiological parameters. Proper operation of these devices depends on the continuous reliable supply of power. A battery, which is the conventional method to supply energy, is problematic in many of these devices as it limits the lifetime of the implant or dominates the size. In order to power implantable devices, power transfer techniques have been implemented as an attractive alternative to batteries and have received significant research interest in recent years. Acoustic waves are increasingly being investigated as a method for delivering power through human skin and the human body. Acoustic power transfer (APT) has some advantages over other powering techniques such as inductive power transfer and mid range RF power transmission. These advantages include lower absorption in tissue, shorter wavelength enabling smaller transducers, and higher power intensity threshold for safe operation. This paper will cover the basic physics and modeling of APT and will review the current state of acoustic (or ultrasonic) power transfer for biomedical implants. As the sensing and computational elements for biomedical implants are becoming very small, we devote particular attention to the scaling of acoustic and alternative power transfer techniques. Finally, we present current issues and challenges related to the implementation of this technique for powering implantable devices.
Neural correlates of action perception at the onset of functional grasping

PubMed Central

Daum, Moritz M.; Handl, Andrea; Gredebäck, Gustaf

2015-01-01

Event-related potentials were recorded while infants observe congruent or incongruent grasping actions at the age when organized grasping first emerges (4–6 months of age). We demonstrate that the event-related potential component P400 encodes the congruency of power grasps at the age of 6 months (Experiment 1) and in 5-month-old infants that have developed the ability to use power grasps (Experiment 2). This effect does not extend to precision grasps, which infants cannot perform (Experiment 3). Our findings suggest that infants’ encoding of the relationship between an object and a grasping hand (the action–perception link) is highly specialized to actions and manual configurations of actions that infants are able to perform. PMID:25193947
The Future of Centrally-Organized Wholesale Electricity Markets

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

Glazer, Craig; Morrison, Jay; Breakman, Paul

The electricity grid in the United States is organized around a network of large, centralized power plants and high voltage transmission lines that transport electricity, sometimes over large distances, before it is delivered to the customer through a local distribution grid. This network of centralized generation and high voltage transmission lines is called the “bulk power system.” Costs relating to bulk power generation typically account for more than half of a customer’s electric bill.1 For this reason, the structure and functioning of wholesale electricity markets have major impacts on costs and economic value for consumers, as well as energy securitymore » and national security. Diverse arrangements for bulk power wholesale markets have evolved over the last several decades. The Southeast and Western United States outside of California have a “bilateral-based” bulk power system where market participants enter into long-term bilateral agreements — using competitive procurements through power marketers, direct arrangements among utilities or with other generation owners, and auctions and exchanges.« less
Preliminary test results from a free-piston Stirling engine technology demonstration program to support advanced radioisotope space power applications

NASA Astrophysics Data System (ADS)

White, Maurice A.; Qiu, Songgang; Augenblick, Jack E.

2000-01-01

Free-piston Stirling engines offer a relatively mature, proven, long-life technology that is well-suited for advanced, high-efficiency radioisotope space power systems. Contracts from DOE and NASA are being conducted by Stirling Technology Company (STC) for the purpose of demonstrating the Stirling technology in a configuration and power level that is representative of an eventual space power system. The long-term objective is to develop a power system with an efficiency exceeding 20% that can function with a high degree of reliability for up to 15 years on deep space missions. The current technology demonstration convertors (TDC's) are completing shakedown testing and have recently demonstrated performance levels that are virtually identical to projections made during the preliminary design phase. This paper describes preliminary test results for power output, efficiency, and vibration levels. These early results demonstrate the ability of the free-piston Stirling technology to exceed objectives by approximately quadrupling the efficiency of conventional radioisotope thermoelectric generators (RTG's). .
Corneal Power Distribution and Functional Optical Zone Following Small Incision Lenticule Extraction for Myopia.

PubMed

Qian, Yishan; Huang, Jia; Zhou, Xingtao; Hanna, Rewais Benjamin

2015-08-01

To evaluate corneal power distribution using the ray tracing method (corneal power) in eyes undergoing small incision lenticule extraction (SMILE) surgery and compare the functional optical zone with two lenticular sizes. This retrospective study evaluated 128 patients who underwent SMILE for the correction of myopia and astigmatism with a lenticular diameter of 6.5 mm (the 6.5-mm group) and 6.2 mm (the 6.2-mm group). The data include refraction, correction, and corneal power obtained via a Scheimpflug camera from the pupil center to 8 mm. The surgically induced changes in corneal power (Δcorneal power) were compared to correction and Δrefraction. The functional optical zone was defined as the largest ring diameter when the difference between the ring power and the pupil center power was 1.50 diopters or less. The functional optical zone was compared between two lenticular diameter groups. Corneal power distribution was measured by the ray tracing method. In the 6.5-mm group (n=100), Δcorneal power at 5 mm showed the smallest difference from Δrefraction and Δcorneal power at 0 mm exhibited the smallest difference from correction. In the 6.2-mm group (n=28), Δcorneal power at 2 mm displayed the lowest dissimilarity from Δrefraction and Δcorneal power at 4 mm demonstrated the lowest dissimilarity from correction. There was no significant difference between the mean postoperative functional optical zones in either group when their spherical equivalents were matched. Total corneal refactive power can be used in the evaluation of surgically induced changes following SMILE. A lenticular diameter of 6.2 mm should be recommended for patients with high myopia because there is no functional difference in the optical zone. Copyright 2015, SLACK Incorporated.
Primary Visual Cortex Scales Individual's Perceived Brightness with Power Function: Inner Psychophysics with fMRI

ERIC Educational Resources Information Center

Tsubomi, Hiroyuki; Ikeda, Takashi; Osaka, Naoyuki

2012-01-01

Perceived brightness is well described by Stevens' power function (S. S. Stevens, 1957, On the psychophysical law, "Psychological Review", Vol. 64, pp. 153-181), with a power exponent of 0.33 (the cubic-root function of luminance). The power exponent actually varies across individuals, yet little is known about neural substrates underlying this…
Pharmacological approaches to restore mitochondrial function

PubMed Central

Andreux, Pénélope A.; Houtkooper, Riekelt H.; Auwerx, Johan

2014-01-01

Mitochondrial dysfunction is not only a hallmark of rare inherited mitochondrial disorders, but is also implicated in age-related diseases, including those that affect the metabolic and nervous system, such as type 2 diabetes and Parkinson’s disease. Numerous pathways maintain and/or restore proper mitochondrial function, including mitochondrial biogenesis, mitochondrial dynamics, mitophagy, and the mitochondrial unfolded protein response. New and powerful phenotypic assays in cell-based models, as well as multicellular organisms, have been developed to explore these different aspects of mitochondrial function. Modulating mitochondrial function has therefore emerged as an attractive therapeutic strategy for a range of diseases, which has spurred active drug discovery efforts in this area. PMID:23666487

Differential effects of power training versus functional task practice on compensation and restoration of arm function after stroke.

PubMed

Corti, Manuela; McGuirk, Theresa E; Wu, Samuel S; Patten, Carolynn

2012-09-01

Improved upper-extremity (UE) movement with stroke rehabilitation may involve restoration of more normal or development of compensatory movement patterns. The authors investigated the differential effects of functional task practice (FTP) and dynamic resistance training (POWER) on clinical function and reaching kinematics in an effort to distinguish between mechanisms of gains. A total of 14 hemiparetic individuals were randomly assigned to 10 weeks of either FTP or POWER and then crossed over to 10 weeks of the alternate treatment. Treatment order A was FTP followed by POWER, whereas treatment order B was POWER followed by FTP. Evaluation before and after each treatment block included a battery of clinical evaluations and kinematics of paretic UE functional reach to grasp. Both FTP and POWER improved movement accuracy, as revealed by a shift toward normal, including fewer submovements and reduced reach-path ratio. However, active range of motion revealed differential treatment effects. Shoulder flexion and elbow extension decreased with FTP and were associated with increased trunk displacement. In contrast, shoulder flexion and elbow extension excursion increased with POWER and were associated with significantly reduced trunk displacement. Treatment order B (POWER followed by FTP) revealed greater overall improvements. FTP increases compensatory movement patterns to improve UE function. POWER leads to more normal movement patterns. POWER prior to FTP may enhance the benefits of repetitive task practice.
Learning curves in highly skilled chess players: a test of the generality of the power law of practice.

PubMed

Howard, Robert W

2014-09-01

The power law of practice holds that a power function best interrelates skill performance and amount of practice. However, the law's validity and generality are moot. Some researchers argue that it is an artifact of averaging individual exponential curves while others question whether the law generalizes to complex skills and to performance measures other than response time. The present study tested the power law's generality to development over many years of a very complex cognitive skill, chess playing, with 387 skilled participants, most of whom were grandmasters. A power or logarithmic function best fit grouped data but individuals showed much variability. An exponential function usually was the worst fit to individual data. Groups differing in chess talent were compared and a power function best fit the group curve for the more talented players while a quadratic function best fit that for the less talented. After extreme amounts of practice, a logarithmic function best fit grouped data but a quadratic function best fit most individual curves. Individual variability is great and the power law or an exponential law are not the best descriptions of individual chess skill development. Copyright © 2014 Elsevier B.V. All rights reserved.
Biomechanical mechanisms underlying exosuit-induced improvements in walking economy after stroke.

PubMed

Bae, Jaehyun; Awad, Louis N; Long, Andrew; O'Donnell, Kathleen; Hendron, Katy; Holt, Kenneth G; Ellis, Terry D; Walsh, Conor J

2018-03-07

Stroke-induced hemiparetic gait is characteristically asymmetric and metabolically expensive. Weakness and impaired control of the paretic ankle contribute to reduced forward propulsion and ground clearance - walking subtasks critical for safe and efficient locomotion. Targeted gait interventions that improve paretic ankle function after stroke are therefore warranted. We have developed textile-based, soft wearable robots that transmit mechanical power generated by off-board or body-worn actuators to the paretic ankle using Bowden cables (soft exosuits) and have demonstrated the exosuits can overcome deficits in paretic limb forward propulsion and ground clearance, ultimately reducing the metabolic cost of hemiparetic walking. This study elucidates the biomechanical mechanisms underlying exosuit-induced reductions in metabolic power. We evaluated the relationships between exosuit-induced changes in the body center of mass (COM) power generated by each limb, individual joint power and metabolic power. Compared with walking with an exosuit unpowered, exosuit assistance produced more symmetrical COM power generation during the critical period of the step-to-step transition (22.4±6.4% more symmetric). Changes in individual limb COM power were related to changes in paretic ( R 2 =0.83, P= 0.004) and non-paretic ( R 2 = 0.73, P= 0.014) ankle power. Interestingly, despite the exosuit providing direct assistance to only the paretic limb, changes in metabolic power were related to changes in non-paretic limb COM power ( R 2 =0.80, P= 0.007), not paretic limb COM power ( P> 0.05). These findings contribute to a fundamental understanding of how individuals post-stroke interact with an exosuit to reduce the metabolic cost of hemiparetic walking. © 2018. Published by The Company of Biologists Ltd.
Early effects of ageing on the mechanical performance of isolated locomotory (EDL) and respiratory (diaphragm) skeletal muscle using the work-loop technique.

PubMed

Tallis, Jason; James, Rob S; Little, Alexander G; Cox, Val M; Duncan, Michael J; Seebacher, Frank

2014-09-15

Previous isolated muscle studies examining the effects of ageing on contractility have used isometric protocols, which have been shown to have poor relevance to dynamic muscle performance in vivo. The present study uniquely uses the work-loop technique for a more realistic estimation of in vivo muscle function to examine changes in mammalian skeletal muscle mechanical properties with age. Measurements of maximal isometric stress, activation and relaxation time, maximal power output, and sustained power output during repetitive activation and recovery are compared in locomotory extensor digitorum longus (EDL) and core diaphragm muscle isolated from 3-, 10-, 30-, and 50-wk-old female mice to examine the early onset of ageing. A progressive age-related reduction in maximal isometric stress that was of greater magnitude than the decrease in maximal power output occurred in both muscles. Maximal force and power developed earlier in diaphragm than EDL muscle but demonstrated a greater age-related decline. The present study indicates that ability to sustain skeletal muscle power output through repetitive contraction is age- and muscle-dependent, which may help rationalize previously reported equivocal results from examination of the effect of age on muscular endurance. The age-related decline in EDL muscle performance is prevalent without a significant reduction in muscle mass, and biochemical analysis of key marker enzymes suggests that although there is some evidence of a more oxidative fiber type, this is not the primary contributor to the early age-related reduction in muscle contractility. Copyright © 2014 the American Physiological Society.
Problematizing special observation in psychiatry: Foucault, archaeology, genealogy, discourse and power/knowledge.

PubMed

Stevenson, C; Cutcliffe, J

2006-12-01

Special observation by mental health professionals is the recommended approach for those people deemed as at risk or risky. Recent research and academic writing have challenged the benefits of observing people/patients who are defined as 'at risk', and a more human engagement process is being recommended. Despite this assault, practice has not changed substantively, suggesting a need for a thorough exploration and questioning of the practices and process. The paper outlines three Foucaultian approaches to historical analysis. It applies aspects of Foucault's archaeology/genealogy, discourse and power/knowledge to explore the practices of special observation as a means of controlling risk, especially suicide risk. We identify the regulatory function of the 'gaze', professional codes and government policy in relation to restricting professional practices. We argue that observation can be related to moral therapy, wherein the person relinquishes madness for responsibility through a disciplinary process and, in governing risk, a 'professional industry' is created. The regulation of statements about people with mental health issues are exposed and related to what can be said and done by professionals. Finally, we look at productive power in relation to observation, and how it is intimately related to resistance. We conclude with 'soft' recommendations for practice discursively produced through the writing of the paper.
Physical function in older men with hyperkyphosis.

PubMed

Katzman, Wendy B; Harrison, Stephanie L; Fink, Howard A; Marshall, Lynn M; Orwoll, Eric; Barrett-Connor, Elizabeth; Cawthon, Peggy M; Kado, Deborah M

2015-05-01

Age-related hyperkyphosis has been associated with poor physical function and is a well-established predictor of adverse health outcomes in older women, but its impact on health in older men is less well understood. We conducted a cross-sectional study to evaluate the association of hyperkyphosis and physical function in 2,363 men, aged 71-98 (M = 79) from the Osteoporotic Fractures in Men Study. Kyphosis was measured using the Rancho Bernardo Study block method. Measurements of grip strength and lower extremity function, including gait speed over 6 m, narrow walk (measure of dynamic balance), repeated chair stands ability and time, and lower extremity power (Nottingham Power Rig) were included separately as primary outcomes. We investigated associations of kyphosis and each outcome in age-adjusted and multivariable linear or logistic regression models, controlling for age, clinic, education, race, bone mineral density, height, weight, diabetes, and physical activity. In multivariate linear regression, we observed a dose-related response of worse scores on each lower extremity physical function test as number of blocks increased, p for trend ≤.001. Using a cutoff of ≥4 blocks, 20% (N = 469) of men were characterized with hyperkyphosis. In multivariate logistic regression, men with hyperkyphosis had increased odds (range 1.5-1.8) of being in the worst quartile of performing lower extremity physical function tasks (p < .001 for each outcome). Kyphosis was not associated with grip strength in any multivariate analysis. Hyperkyphosis is associated with impaired lower extremity physical function in older men. Further studies are needed to determine the direction of causality. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Lean muscle volume of the thigh has a stronger relationship with muscle power than muscle strength in women with knee osteoarthritis.

PubMed

Davison, Michael J; Maly, Monica R; Keir, Peter J; Hapuhennedige, Sandani M; Kron, Amie T; Adachi, Jonathan D; Beattie, Karen A

2017-01-01

Thigh lean muscle and intramuscular fat have been implicated in the impairment of physical function observed in people with knee osteoarthritis. We investigated the relationships of quadriceps and hamstrings intramuscular fat fraction and lean muscle volume with muscle power and strength, controlling for neuromuscular activation, and physical performance in women with knee OA. Women (n=20) 55years or older with symptomatic, radiographic knee osteoarthritis underwent a 3.0T magnetic resonance imaging scan of the thigh of their most symptomatic knee. Axial fat-separated images were analyzed using software to quantify intramuscular fat and lean muscle volumes of the quadriceps and hamstrings. To quantify strength and power of the knee extensors and flexors, participants performed maximum voluntary isometric contraction and isotonic knee extensions and flexions, respectively. Electromyography of the quadriceps and hamstrings was measured. Participants also completed five physical performance tests. Quadriceps and hamstrings lean muscle volumes were related to isotonic knee extensor (B=0.624; p=0.017) and flexor (B=1.518; p=0.032) power, but not knee extensor (B=0.001; p=0.615) or flexor (B=0.001; p=0.564) isometric strength. Intramuscular fat fractions were not related to isotonic knee extensor or flexor power, nor isometric strength. No relationships were found between intramuscular fat or lean muscle volume and physical performance. Muscle power may be more sensitive than strength to lean muscle mass in women with knee osteoarthritis. Thigh lean muscle mass, but neither intramuscular nor intermuscular fat, is related to knee extensor and flexor power in women with knee osteoarthritis. Copyright © 2016 Elsevier Ltd. All rights reserved.
STAR FORMATION LAWS: THE EFFECTS OF GAS CLOUD SAMPLING

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

Calzetti, D.; Liu, G.; Koda, J., E-mail: calzetti@astro.umass.edu

Recent observational results indicate that the functional shape of the spatially resolved star formation-molecular gas density relation depends on the spatial scale considered. These results may indicate a fundamental role of sampling effects on scales that are typically only a few times larger than those of the largest molecular clouds. To investigate the impact of this effect, we construct simple models for the distribution of molecular clouds in a typical star-forming spiral galaxy and, assuming a power-law relation between star formation rate (SFR) and cloud mass, explore a range of input parameters. We confirm that the slope and the scattermore » of the simulated SFR-molecular gas surface density relation depend on the size of the sub-galactic region considered, due to stochastic sampling of the molecular cloud mass function, and the effect is larger for steeper relations between SFR and molecular gas. There is a general trend for all slope values to tend to {approx}unity for region sizes larger than 1-2 kpc, irrespective of the input SFR-cloud relation. The region size of 1-2 kpc corresponds to the area where the cloud mass function becomes fully sampled. We quantify the effects of selection biases in data tracing the SFR, either as thresholds (i.e., clouds smaller than a given mass value do not form stars) or as backgrounds (e.g., diffuse emission unrelated to current star formation is counted toward the SFR). Apparently discordant observational results are brought into agreement via this simple model, and the comparison of our simulations with data for a few galaxies supports a steep (>1) power-law index between SFR and molecular gas.« less
Novel Analog For Muscle Deconditioning

NASA Technical Reports Server (NTRS)

Ploutz-Snyder, Lori; Ryder, Jeff; Buxton, Roxanne; Redd, Elizabeth; Scott-Pandorf, Melissa; Hackney, Kyle; Fiedler, James; Bloomberg, Jacob

2010-01-01

Existing models of muscle deconditioning are cumbersome and expensive (ex: bedrest). We propose a new model utilizing a weighted suit to manipulate strength, power or endurance (function) relative to body weight (BW). Methods: 20 subjects performed 7 occupational astronaut tasks while wearing a suit weighted with 0-120% of BW. Models of the full relationship between muscle function/BW and task completion time were developed using fractional polynomial regression and verified by the addition of pre- and post-flight astronaut performance data using the same tasks. Spline regression was used to identify muscle function thresholds below which task performance was impaired. Results: Thresholds of performance decline were identified for each task. Seated egress & walk (most difficult task) showed thresholds of: leg press (LP) isometric peak force/BW of 18 N/kg, LP power/BW of 18 W/kg, LP work/ BW of 79 J/kg, knee extension (KE) isokinetic/BW of 6 Nm/Kg and KE torque/BW of 1.9 Nm/kg. Conclusions: Laboratory manipulation of strength / BW has promise as an appropriate analog for spaceflight-induced loss of muscle function for predicting occupational task performance and establishing operationally relevant exercise targets.
Reactivity of hemodynamic responses and functional connectivity to different states of alpha synchrony: a concurrent EEG-fMRI study.

PubMed

Wu, Lei; Eichele, Tom; Calhoun, Vince D

2010-10-01

Concurrent EEG-fMRI studies have provided increasing details of the dynamics of intrinsic brain activity during the resting state. Here, we investigate a prominent effect in EEG during relaxed resting, i.e. the increase of the alpha power when the eyes are closed compared to when the eyes are open. This phenomenon is related to changes in thalamo-cortical and cortico-cortical synchronization. In order to investigate possible changes to EEG-fMRI coupling and fMRI functional connectivity during the two states we adopted a data-driven approach that fuses the multimodal data on the basis of parallel ICA decompositions of the fMRI data in the spatial domain and of the EEG data in the spectral domain. The power variation of a posterior alpha component was used as a reference function to deconvolve the hemodynamic responses from occipital, frontal, temporal, and subcortical fMRI components. Additionally, we computed the functional connectivity between these components. The results showed widespread alpha hemodynamic responses and high functional connectivity during eyes-closed (EC) rest, while eyes open (EO) resting abolished many of the hemodynamic responses and markedly decreased functional connectivity. These data suggest that generation of local hemodynamic responses is highly sensitive to state changes that do not involve changes of mental effort or awareness. They also indicate the localized power differences in posterior alpha between EO and EC in resting state data are accompanied by spatially widespread amplitude changes in hemodynamic responses and inter-regional functional connectivity, i.e. low frequency hemodynamic signals display an equivalent of alpha reactivity. Copyright 2010 Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)

Hugo, Jacques

The software application is called "HFE-Trace". This is an integrated method and tool for the management of Human Factors Engineering analyses and related data. Its primary purpose is to support the coherent and consistent application of the nuclear industry's best practices for human factors engineering work. The software is a custom Microsoft® Access® application. The application is used (in conjunction with other tools such as spreadsheets, checklists and normal documents where necessary) to collect data on the design of a new nuclear power plant from subject matter experts and other sources. This information is then used to identify potential systemmore » and functional breakdowns of the intended power plant design. This information is expanded by developing extensive descriptions of all functions, as well as system performance parameters, operating limits and constraints, and operational conditions. Once these have been verified, the human factors elements are added to each function, including intended operator role, function allocation considerations, prohibited actions, primary task categories, and primary work station. In addition, the application includes a computational method to assess a number of factors such as system and process complexity, workload, environmental conditions, procedures, regulations, etc.) that may shape operator performance. This is a unique methodology based upon principles described in NUREG/CR-3331 ("A methodology for allocating nuclear power plant control functions to human or automatic control") and it results in a semi-quantified allocation of functions to three or more levels of automation for a conceptual automation system. The aggregate of all this information is then linked to the Task Analysis section of the application where the existing information on all operator functions is transformed into task information and ultimately into design requirements for Human-System Interfaces and Control Rooms. This final step includes assessment of methods to prevent potential operator errors.« less
Improving vision by pupil masking

PubMed Central

Bonaque-González, Sergio; Ríos-Rodríguez, Susana; López-Gil, Norberto

2016-01-01

We propose an alternative solution to improve visual quality by spatially modulating the amplitude of light passing into the eye (related to the eye's transmittance), in contrast to traditional correction of the wavefront phase (related to the local refractive power). Numerical simulations show that masking the aberrated areas at the pupil plane should enhance visual function, especially in highly aberrated eyes. This correction could be implemented in practice using customized contact or intraocular lenses. PMID:27446688
DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Jie; Jain, Rishabh; Hodge, Bri-Mathias

A data-driven methodology is developed to analyze how ambient and wake turbulence affect the power generation of wind turbine(s). Using supervisory control and data acquisition (SCADA) data from a wind plant, we select two sets of wind velocity and power data for turbines on the edge of the plant that resemble (i) an out-of-wake scenario and (ii) an in-wake scenario. For each set of data, two surrogate models are developed to represent the turbine(s) power generation as a function of (i) the wind speed and (ii) the wind speed and turbulence intensity. Three types of uncertainties in turbine(s) power generationmore » are investigated: (i) the uncertainty in power generation with respect to the reported power curve; (ii) the uncertainty in power generation with respect to the estimated power response that accounts for only mean wind speed; and (iii) the uncertainty in power generation with respect to the estimated power response that accounts for both mean wind speed and turbulence intensity. Results show that (i) the turbine(s) generally produce more power under the in-wake scenario than under the out-of-wake scenario with the same wind speed; and (ii) there is relatively more uncertainty in the power generation under the in-wake scenario than under the out-of-wake scenario.« less
Statistical power as a function of Cronbach alpha of instrument questionnaire items.

PubMed

Heo, Moonseong; Kim, Namhee; Faith, Myles S

2015-10-14

In countless number of clinical trials, measurements of outcomes rely on instrument questionnaire items which however often suffer measurement error problems which in turn affect statistical power of study designs. The Cronbach alpha or coefficient alpha, here denoted by C(α), can be used as a measure of internal consistency of parallel instrument items that are developed to measure a target unidimensional outcome construct. Scale score for the target construct is often represented by the sum of the item scores. However, power functions based on C(α) have been lacking for various study designs. We formulate a statistical model for parallel items to derive power functions as a function of C(α) under several study designs. To this end, we assume fixed true score variance assumption as opposed to usual fixed total variance assumption. That assumption is critical and practically relevant to show that smaller measurement errors are inversely associated with higher inter-item correlations, and thus that greater C(α) is associated with greater statistical power. We compare the derived theoretical statistical power with empirical power obtained through Monte Carlo simulations for the following comparisons: one-sample comparison of pre- and post-treatment mean differences, two-sample comparison of pre-post mean differences between groups, and two-sample comparison of mean differences between groups. It is shown that C(α) is the same as a test-retest correlation of the scale scores of parallel items, which enables testing significance of C(α). Closed-form power functions and samples size determination formulas are derived in terms of C(α), for all of the aforementioned comparisons. Power functions are shown to be an increasing function of C(α), regardless of comparison of interest. The derived power functions are well validated by simulation studies that show that the magnitudes of theoretical power are virtually identical to those of the empirical power. Regardless of research designs or settings, in order to increase statistical power, development and use of instruments with greater C(α), or equivalently with greater inter-item correlations, is crucial for trials that intend to use questionnaire items for measuring research outcomes. Further development of the power functions for binary or ordinal item scores and under more general item correlation strutures reflecting more real world situations would be a valuable future study.
Gender differences in job strain, effort-reward imbalance, and health functioning among Chinese physicians.

PubMed

Li, Jian; Yang, Wenjie; Cho, Sung-Il

2006-03-01

To examine the association between work stress measured by job strain and effort-reward imbalance (ERI) and health functioning in a sample of hospital-based Chinese physicians, a self-reported survey with a standardized questionnaire was conducted in three hospitals in China, among 256 men and 266 women. It was found that both job strain and ERI were associated with impaired health functioning in men and women, but that ERI indicated a stronger association. Men's job control was significantly higher, and was related to men's physical health; whereas women perceived relatively higher job reward which predicted women's mental health. The findings provide evidence of the adverse effects on health functioning of both job strain and ERI, but ERI appears to have more explanatory power as a model of work stress in this sample of Chinese physicians. In addition, gender differences of work stress with respect to health are present.
Characterization of Hand Clenching in Human Sensorimotor Cortex Using High-, and Ultra-High Frequency Band Modulations of Electrocorticogram

PubMed Central

Jiang, Tianxiao; Liu, Su; Pellizzer, Giuseppe; Aydoseli, Aydin; Karamursel, Sacit; Sabanci, Pulat A.; Sencer, Altay; Gurses, Candan; Ince, Nuri F.

2018-01-01

Functional mapping of eloquent cortex before the resection of a tumor is a critical procedure for optimizing survival and quality of life. In order to locate the hand area of the motor cortex in two patients with low-grade gliomas (LGG), we recorded electrocorticogram (ECoG) from a 113 channel hybrid high-density grid (64 large contacts with diameter of 2.7 mm and 49 small contacts with diameter of 1 mm) while they executed hand clenching movements. We investigated the spatio-spectral characteristics of the neural oscillatory activity and observed that, in both patients, the hand movements were consistently associated with a wide spread power decrease in the low frequency band (LFB: 8–32 Hz) and a more localized power increase in the high frequency band (HFB: 60–280 Hz) within the sensorimotor region. Importantly, we observed significant power increase in the ultra-high frequency band (UFB: 300–800 Hz) during hand movements of both patients within a restricted cortical region close to the central sulcus, and the motor cortical “hand knob.” Among all frequency bands we studied, the UFB modulations were closest to the central sulcus and direct cortical stimulation (DCS) positive site. Both HFB and UFB modulations exhibited different timing characteristics at different locations. Power increase in HFB and UFB starting before movement onset was observed mostly at the anterior part of the activated cortical region. In addition, the spatial patterns in HFB and UFB indicated a probable postcentral shift of the hand motor function in one of the patients. We also compared the task related subband modulations captured by the small and large contacts in our hybrid grid. We did not find any significant difference in terms of band power changes. This study shows initial evidence that event-driven neural oscillatory activity recorded from ECoG can reach up to 800 Hz. The spatial distribution of UFB oscillations was found to be more focalized and closer to the central sulcus compared to LFB and HFB. More studies are needed to characterize further the functional significance of UFB relative to LFB and HFB. PMID:29535603
Characterization of Hand Clenching in Human Sensorimotor Cortex Using High-, and Ultra-High Frequency Band Modulations of Electrocorticogram.

PubMed

Jiang, Tianxiao; Liu, Su; Pellizzer, Giuseppe; Aydoseli, Aydin; Karamursel, Sacit; Sabanci, Pulat A; Sencer, Altay; Gurses, Candan; Ince, Nuri F

2018-01-01

Functional mapping of eloquent cortex before the resection of a tumor is a critical procedure for optimizing survival and quality of life. In order to locate the hand area of the motor cortex in two patients with low-grade gliomas (LGG), we recorded electrocorticogram (ECoG) from a 113 channel hybrid high-density grid (64 large contacts with diameter of 2.7 mm and 49 small contacts with diameter of 1 mm) while they executed hand clenching movements. We investigated the spatio-spectral characteristics of the neural oscillatory activity and observed that, in both patients, the hand movements were consistently associated with a wide spread power decrease in the low frequency band (LFB: 8-32 Hz) and a more localized power increase in the high frequency band (HFB: 60-280 Hz) within the sensorimotor region. Importantly, we observed significant power increase in the ultra-high frequency band (UFB: 300-800 Hz) during hand movements of both patients within a restricted cortical region close to the central sulcus, and the motor cortical "hand knob." Among all frequency bands we studied, the UFB modulations were closest to the central sulcus and direct cortical stimulation (DCS) positive site. Both HFB and UFB modulations exhibited different timing characteristics at different locations. Power increase in HFB and UFB starting before movement onset was observed mostly at the anterior part of the activated cortical region. In addition, the spatial patterns in HFB and UFB indicated a probable postcentral shift of the hand motor function in one of the patients. We also compared the task related subband modulations captured by the small and large contacts in our hybrid grid. We did not find any significant difference in terms of band power changes. This study shows initial evidence that event-driven neural oscillatory activity recorded from ECoG can reach up to 800 Hz. The spatial distribution of UFB oscillations was found to be more focalized and closer to the central sulcus compared to LFB and HFB. More studies are needed to characterize further the functional significance of UFB relative to LFB and HFB.
A mechanism producing power law etc. distributions

NASA Astrophysics Data System (ADS)

Li, Heling; Shen, Hongjun; Yang, Bin

2017-07-01

Power law distribution is playing an increasingly important role in the complex system study. Based on the insolvability of complex systems, the idea of incomplete statistics is utilized and expanded, three different exponential factors are introduced in equations about the normalization condition, statistical average and Shannon entropy, with probability distribution function deduced about exponential function, power function and the product form between power function and exponential function derived from Shannon entropy and maximal entropy principle. So it is shown that maximum entropy principle can totally replace equal probability hypothesis. Owing to the fact that power and probability distribution in the product form between power function and exponential function, which cannot be derived via equal probability hypothesis, can be derived by the aid of maximal entropy principle, it also can be concluded that maximal entropy principle is a basic principle which embodies concepts more extensively and reveals basic principles on motion laws of objects more fundamentally. At the same time, this principle also reveals the intrinsic link between Nature and different objects in human society and principles complied by all.
Immunological parameters in elderly women: correlations with aerobic power, muscle strength and mood state.

PubMed

Raso, Vagner; Natale, Valéria Maria; Duarte, Alberto José da Silva; Greve, Júlia Maria D'Andrea; Shephard, Roy J

2012-05-01

Our objective was to relate immunological data for healthy but sedentary elderly women to aerobic power, strength, and mood state. We measured peak aerobic power and one-repetition maximum strength along with mood (depression and fatigue), quality of life and carbohydrate intake on 42 women aged 60-77 years. Standard immunological techniques determined natural killer cell count and cytotoxic activity (NKCA), proliferative responses to phytohemaglutinin and OKT(3), various lymphocyte subpopulations (CD3(+), CD3(-)CD19(+), CD56(+), CD4(+), CD8(+), CD56(dim) and CD56(bright)), and markers of activation, maturation, down-regulation and susceptibility to apoptosis (CD25(+), CD28(+), CD45RA(+), CD45RO(+), CD69(+), CD95(+), HLA-DR(+)). Correlations of immune parameters with aerobic power and strength were very similar for absolute and relative immunological data. In the group as a whole, the only correlation with aerobic power was -0.35 (relative CD4(+)CD69(+) count), but in subjects with values <22.6 mL kg(-1)min(-1) correlations ranged from -0.57 (relative CD4(+)CD45RO(+)) to 0.92 (absolute CD56(dim)HLA-DR(+)). In terms of muscle strength, univariate correlation coefficients ranged from -0.34 (relative and absolute CD3(+)CD4(+)CD8(+)) to +0.48 (absolute CD3(+)HLA-DR(+)) and +0.50 (absolute CD8(+)CD45RA(+)CD45RO(+)). Neither NKCA nor lymphocyte proliferation were correlated with aerobic power or muscle strength. Although mood state and quality of life can sometimes be influenced by an individual's fitness level, our multivariate analyses suggested that depression, fatigue and quality of life were more important determinants of immune profile than our fitness measures. Psychological changes associated with aging may have a substantial adverse effect upon the immune system, and immunological function may be enhanced more by addressing these issues than by focusing upon aerobic or resistance training. Copyright © 2012 Elsevier Inc. All rights reserved.
Integrated air revitalization system for Space Station

NASA Technical Reports Server (NTRS)

Boyda, R. B.; Miller, C. W.; Schwartz, M. R.

1986-01-01

Fifty-one distinct functions are encompassed by the Space Station's Environmental Control and Life Support System; one exception to this noninteractivity of functions is the regenerative air revitalization system that removes and reduces CO2 and generates O2. The integration of these interdependent functions, and of humidity control, into a single system furnishes opportunities for process simplification as well as for power, weight and volume requirement reductions by comparison with discrete subsystems. Attention is presently given to a system which quantifies these integration-related savings and identifies additional advantages that accrue to this integrating design method.

Differences in MEG gamma oscillatory power during performance of a prosaccade task in adolescents with FASD

PubMed Central

Stephen, Julia M.; Coffman, Brian A.; Stone, David B.; Kodituwakku, Piyadasa

2013-01-01

Fetal alcohol spectrum disorder (FASD) is characterized by a broad range of behavioral and cognitive deficits that impact the long-term quality of life for affected individuals. However, the underlying changes in brain structure and function associated with these cognitive impairments are not well-understood. Previous studies identified deficits in behavioral performance of prosaccade tasks in children with FASD. In this study, we investigated group differences in gamma oscillations during performance of a prosaccade task. We collected magnetoencephalography (MEG) data from 15 adolescents with FASD and 20 age-matched healthy controls (HC) with a mean age of 15.9 ± 0.4 years during performance of a prosaccade task. Eye movement was recorded and synchronized to the MEG data using an MEG compatible eye-tracker. The MEG data were analyzed relative to the onset of the visual saccade. Time-frequency analysis was performed using Fieldtrip with a focus on group differences in gamma-band oscillations. Following left target presentation, we identified four clusters over right frontal, right parietal, and left temporal/occipital cortex, with significantly different gamma-band (30–50 Hz) power between FASD and HC. Furthermore, visual M100 latencies described in Coffman etal. (2012) corresponded with increased gamma power over right central cortex in FASD only. Gamma-band differences were not identified for stimulus-averaged responses implying that these gamma-band differences were related to differences in saccade network functioning. These differences in gamma-band power may provide indications of atypical development of cortical networks in individuals with FASD. PMID:24399957
Linking an Anxiety-Related Personality Trait to Cardiac Autonomic Regulation in Well-Defined Healthy Adults: Harm Avoidance and Resting Heart Rate Variability.

PubMed

Kao, Lien-Cheng; Liu, Yu-Wen; Tzeng, Nian-Sheng; Kuo, Terry B J; Huang, San-Yuan; Chang, Chuan-Chia; Chang, Hsin-An

2016-07-01

Anxiety trait, anxiety and depression states have all been reported to increase risks for cardiovascular disease (CVD), possibly through altering cardiac autonomic regulation. Our aim was to investigate whether the relationship between harm avoidance (HA, an anxiety-related personality trait) and cardiac autonomic regulation is independent of anxiety and depression states in healthy adults. We recruited 535 physically and mentally healthy volunteers. Participants completed the Beck Anxiety Inventory (BAI), Beck Depression Inventory (BDI) and Tri-dimensional Personality Questionnaire. Participants were divided into high or low HA groups as discriminated by the quartile value. Cardiac autonomic function was evaluated by measuring heart rate variability (HRV). We obtained the time and frequency-domain indices of HRV including variance (total HRV), the low-frequency power (LF; 0.05-0.15 Hz), which may reflect baroreflex function, the high-frequency power (HF; 0.15-0.40 Hz), which reflects cardiac parasympathetic activity, as well as the LF/HF ratio. The BDI and HA scores showed associations with HRV parameters. After adjustment for the BDI scores and other control variables, HA is still associated with reduced variance, LF and HF power. Compared with the participants with low HA, those with high HA displayed significant reductions in variance, LF and HF power and a significant increase in their LF/HF ratio. This study highlights the independent role of HA in contributing to decreased autonomic cardiac regulation in healthy adults and provides a potential underlying mechanism for anxiety trait to confer increased risk for CVD.
Comparison of a field-based test to estimate functional threshold power and power output at lactate threshold.

PubMed

Gavin, Timothy P; Van Meter, Jessica B; Brophy, Patricia M; Dubis, Gabriel S; Potts, Katlin N; Hickner, Robert C

2012-02-01

It has been proposed that field-based tests (FT) used to estimate functional threshold power (FTP) result in power output (PO) equivalent to PO at lactate threshold (LT). However, anecdotal evidence from regional cycling teams tested for LT in our laboratory suggested that PO at LT underestimated FTP. It was hypothesized that estimated FTP is not equivalent to PO at LT. The LT and estimated FTP were measured in 7 trained male competitive cyclists (VO2max = 65.3 ± 1.6 ml O2·kg(-1)·min(-1)). The FTP was estimated from an 8-minute FT and compared with PO at LT using 2 methods; LT(Δ1), a 1 mmol·L(-1) or greater rise in blood lactate in response to an increase in workload and LT(4.0), blood lactate of 4.0 mmol·L(-1). The estimated FTP was equivalent to PO at LT(4.0) and greater than PO at LT(Δ1). VO2max explained 93% of the variance in individual PO during the 8-minute FT. When the 8-minute FT PO was expressed relative to maximal PO from the VO2max test (individual exercise performance), VO2max explained 64% of the variance in individual exercise performance. The PO at LT was not related to 8-minute FT PO. In conclusion, FTP estimated from an 8-minute FT is equivalent to PO at LT if LT(4.0) is used but is not equivalent for all methods of LT determination including LT(Δ1).
Linking an Anxiety-Related Personality Trait to Cardiac Autonomic Regulation in Well-Defined Healthy Adults: Harm Avoidance and Resting Heart Rate Variability

PubMed Central

Kao, Lien-Cheng; Liu, Yu-Wen; Tzeng, Nian-Sheng; Kuo, Terry B. J.; Huang, San-Yuan

2016-01-01

Objective Anxiety trait, anxiety and depression states have all been reported to increase risks for cardiovascular disease (CVD), possibly through altering cardiac autonomic regulation. Our aim was to investigate whether the relationship between harm avoidance (HA, an anxiety-related personality trait) and cardiac autonomic regulation is independent of anxiety and depression states in healthy adults. Methods We recruited 535 physically and mentally healthy volunteers. Participants completed the Beck Anxiety Inventory (BAI), Beck Depression Inventory (BDI) and Tri-dimensional Personality Questionnaire. Participants were divided into high or low HA groups as discriminated by the quartile value. Cardiac autonomic function was evaluated by measuring heart rate variability (HRV). We obtained the time and frequency-domain indices of HRV including variance (total HRV), the low-frequency power (LF; 0.05–0.15 Hz), which may reflect baroreflex function, the high-frequency power (HF; 0.15–0.40 Hz), which reflects cardiac parasympathetic activity, as well as the LF/HF ratio. Results The BDI and HA scores showed associations with HRV parameters. After adjustment for the BDI scores and other control variables, HA is still associated with reduced variance, LF and HF power. Compared with the participants with low HA, those with high HA displayed significant reductions in variance, LF and HF power and a significant increase in their LF/HF ratio. Conclusion This study highlights the independent role of HA in contributing to decreased autonomic cardiac regulation in healthy adults and provides a potential underlying mechanism for anxiety trait to confer increased risk for CVD. PMID:27482240
Generating log-normal mock catalog of galaxies in redshift space

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

Agrawal, Aniket; Makiya, Ryu; Saito, Shun

We present a public code to generate a mock galaxy catalog in redshift space assuming a log-normal probability density function (PDF) of galaxy and matter density fields. We draw galaxies by Poisson-sampling the log-normal field, and calculate the velocity field from the linearised continuity equation of matter fields, assuming zero vorticity. This procedure yields a PDF of the pairwise velocity fields that is qualitatively similar to that of N-body simulations. We check fidelity of the catalog, showing that the measured two-point correlation function and power spectrum in real space agree with the input precisely. We find that a linear biasmore » relation in the power spectrum does not guarantee a linear bias relation in the density contrasts, leading to a cross-correlation coefficient of matter and galaxies deviating from unity on small scales. We also find that linearising the Jacobian of the real-to-redshift space mapping provides a poor model for the two-point statistics in redshift space. That is, non-linear redshift-space distortion is dominated by non-linearity in the Jacobian. The power spectrum in redshift space shows a damping on small scales that is qualitatively similar to that of the well-known Fingers-of-God (FoG) effect due to random velocities, except that the log-normal mock does not include random velocities. This damping is a consequence of non-linearity in the Jacobian, and thus attributing the damping of the power spectrum solely to FoG, as commonly done in the literature, is misleading.« less
Strength training in the elderly: effects on risk factors for age-related diseases.

PubMed

Hurley, B F; Roth, S M

2000-10-01

Strength training (ST) is considered a promising intervention for reversing the loss of muscle function and the deterioration of muscle structure that is associated with advanced age. This reversal is thought to result in improvements in functional abilities and health status in the elderly by increasing muscle mass, strength and power and by increasing bone mineral density (BMD). In the past couple of decades, many studies have examined the effects of ST on risk factors for age-related diseases or disabilities. Collectively, these studies indicate that ST in the elderly: (i) is an effective intervention against sarcopenia because it produces substantial increases in the strength, mass, power and quality of skeletal muscle; (ii) can increase endurance performance; (iii) normalises blood pressure in those with high normal values; (iv) reduces insulin resistance; (v) decreases both total and intra-abdominal fat; (vi) increases resting metabolic rate in older men; (vii) prevents the loss of BMD with age; (viii) reduces risk factors for falls; and (ix) may reduce pain and improve function in those with osteoarthritis in the knee region. However, contrary to popular belief, ST does not increase maximal oxygen uptake beyond normal variations, improve lipoprotein or lipid profiles, or improve flexibility in the elderly.
Age-related variation in EEG complexity to photic stimulation: A multiscale entropy analysis

PubMed Central

Takahashi, Tetsuya; Cho, Raymond Y.; Murata, Tetsuhito; Mizuno, Tomoyuki; Kikuchi, Mitsuru; Mizukami, Kimiko; Kosaka, Hirotaka; Takahashi, Koichi; Wada, Yuji

2010-01-01

Objective This study was intended to examine variations in electroencephalographic (EEG) complexity in response to photic stimulation (PS) during aging to test the hypothesis that the aging process reduces physiologic complexity and functional responsiveness. Methods Multiscale entropy (MSE), an estimate of time-series signal complexity associated with long-range temporal correlation, is used as a recently proposed method for quantifying EEG complexity with multiple coarse-grained sequences. We recorded EEG in 13 healthy elderly subjects and 12 healthy young subjects during pre-PS and post-PS conditions and estimated their respective MSE values. Results For the pre-PS condition, no significant complexity difference was found between the groups. However, a significant MSE change (complexity increase) was found post-PS only in young subjects, thereby revealing a power-law scaling property, which means long-range temporal correlation. Conclusions Enhancement of long-range temporal correlation in young subjects after PS might reflect a cortical response to stimuli, which was absent in elderly subjects. These results are consistent with the general “loss of complexity/diminished functional response to stimuli” theory of aging. Significance Our findings demonstrate that application of MSE analysis to EEG is a powerful approach for studying age-related changes in brain function. PMID:19231279
Power electronic supply system with the wind turbine dedicated for average power receivers

NASA Astrophysics Data System (ADS)

Widerski, Tomasz; Skrzypek, Adam

2018-05-01

This article presents the original project of the AC-DC-AC converter dedicated to low power wind turbines. Such a set can be a good solution for powering isolated objects that do not have access to the power grid, for example isolated houses, mountain lodges or forester's lodges, where they can replace expensive diesel engine generators. An additional source of energy in the form of a mini-wind farm is also a good alternative to yachts, marinas and tent sites, which are characterized by relatively low power consumption. This article presents a designed low power wind converter that is dedicated to these applications. The main design idea of the authors was to create a device that converts the very wide range input voltage directly to a stable 230VAC output voltage without the battery buffer. Authors focused on maximum safety of using and service. The converter contains the thermal protection, short-circuit protection and overvoltage protection. The components have been selected in such a way as to ensure that the device functions as efficiently as possible.
What do human rights bring to discussions of power and politics in health policy and systems?

PubMed

Forman, Lisa

2017-12-13

Scholarly interrogations of power and politics are not endemic to the disciplines primarily tasked with exploring health policy and planning in the domestic or global domains. Scholars in these domains have come late to investigating power, prompted in part by the growing focus in domestic and global health research on the intersections between governance, globalization and health inequities. Recent prominent reports in this area increasingly point to human rights as important norms capable of responding in part to power differentials that sustain and exacerbate health inequities. Yet human rights law is not traditionally incorporated into health policy scholarship or education, despite offering important normative and strategic frameworks for public and global health, with distinctive contributions in relation to identifying and challenging certain forms of power disparity. This paper overviews two of these reports and how they see power functioning to sustain health inequities. It then turns to investigate what human rights and the right to health in particular may offer in addressing and challenging power in the health policy context.
DOE Office of Scientific and Technical Information (OSTI.GOV)

Seljak, Uroš; McDonald, Patrick, E-mail: useljak@berkeley.edu, E-mail: pvmcdonald@lbl.gov

We develop a phase space distribution function approach to redshift space distortions (RSD), in which the redshift space density can be written as a sum over velocity moments of the distribution function. These moments are density weighted and have well defined physical interpretation: their lowest orders are density, momentum density, and stress energy density. The series expansion is convergent if kμu/aH < 1, where k is the wavevector, H the Hubble parameter, u the typical gravitational velocity and μ = cos θ, with θ being the angle between the Fourier mode and the line of sight. We perform an expansionmore » of these velocity moments into helicity modes, which are eigenmodes under rotation around the axis of Fourier mode direction, generalizing the scalar, vector, tensor decomposition of perturbations to an arbitrary order. We show that only equal helicity moments correlate and derive the angular dependence of the individual contributions to the redshift space power spectrum. We show that the dominant term of μ{sup 2} dependence on large scales is the cross-correlation between the density and scalar part of momentum density, which can be related to the time derivative of the matter power spectrum. Additional terms contributing to μ{sup 2} and dominating on small scales are the vector part of momentum density-momentum density correlations, the energy density-density correlations, and the scalar part of anisotropic stress density-density correlations. The second term is what is usually associated with the small scale Fingers-of-God damping and always suppresses power, but the first term comes with the opposite sign and always adds power. Similarly, we identify 7 terms contributing to μ{sup 4} dependence. Some of the advantages of the distribution function approach are that the series expansion converges on large scales and remains valid in multi-stream situations. We finish with a brief discussion of implications for RSD in galaxies relative to dark matter, highlighting the issue of scale dependent bias of velocity moments correlators.« less
46 CFR 502.147 - Functions and powers.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 9 2011-10-01 2011-10-01 false Functions and powers. 502.147 Section 502.147 Shipping FEDERAL MARITIME COMMISSION GENERAL AND ADMINISTRATIVE PROVISIONS RULES OF PRACTICE AND PROCEDURE Hearings; Presiding Officers; Evidence § 502.147 Functions and powers. (a) Of presiding officer. The officer...
A study of acoustic halos in active region NOAA 11330 using multi-height SDO observations

NASA Astrophysics Data System (ADS)

Tripathy, S. C.; Jain, K.; Kholikov, S.; Hill, F.; Rajaguru, S. P.; Cally, P. S.

2018-01-01

We analyze data from the Helioseismic Magnetic Imager (HMI) and the Atmospheric Imaging Assembly (AIA) instruments on board the Solar Dynamics Observatory (SDO) to characterize the spatio-temporal acoustic power distribution in active regions as a function of the height in the solar atmosphere. For this, we use Doppler velocity and continuum intensity observed using the magnetically sensitive line at 6173 Å as well as intensity at 1600 Å and 1700 Å. We focus on the power enhancements seen around AR 11330 as a function of wave frequency, magnetic field strength, field inclination and observation height. We find that acoustic halos occur above the acoustic cutoff frequency and extends up to 10 mHz in HMI Doppler and AIA 1700 Å observations. Halos are also found to be strong functions of magnetic field and their inclination angle. We further calculate and examine the spatially averaged relative phases and cross-coherence spectra and find different wave characteristics at different heights.
Evaluation of Aero Commander sidewall vibration and interior acoustic data: Static operations

NASA Technical Reports Server (NTRS)

Piersol, A. G.; Wilby, E. G.; Wilby, J. F.

1980-01-01

Results for the vibration measured at five locations on the fuselage structure during static operations are presented. The analysis was concerned with the magnitude of the vibration and the relative phase between different locations, the frequency response (inertance) functions between the exterior pressure field and the vibration, and the coherent output power functions at interior microphone locations based on sidewall vibration. Fuselage skin panels near the plane of rotation of the propeller accept propeller noise excitation more efficiently than they do exhaust noise.
Text-Based Conferencing: Features vs. Functionality

ERIC Educational Resources Information Center

Anderson, Lynn; McCarthy, Cathy

2005-01-01

This report examines three text-based conferencing products: "WowBB", "Invision Power Board", and "vBulletin". Their selection was prompted by a feature-by-feature comparison of the same products on the "WowBB" website. The comparison chart painted a misleading impression of "WowBB's" features in relation to the other two products; so the…
Proceedings of the Symposium on Training of Nuclear Facility Personnel (8th, Gatlinburg, Tennessee, April 24-27, 1989).

ERIC Educational Resources Information Center

Oak Ridge National Lab., TN.

Education-related titles among the 56 papers are "Panel Discussion: Plant Expectation of Training" (Sellman, Zach, Cross); "Managing Training AT&T" (Solomon); "Training Management Systems" (Waylett); "Managing the Training Function" (Wiggin); "Training Management" (Newton); Three Alternative Simulation Systems for Training Nuclear Power Plant…
A Framework for Conceptualizing and Evaluating the Validity of Instructionally Relevant Assessments

ERIC Educational Resources Information Center

Pellegrino, James W.; DiBello, Louis V.; Goldman, Susan R.

2016-01-01

Assessments that function close to classroom teaching and learning can play a powerful role in fostering academic achievement. Unfortunately, however, relatively little attention has been given to discussion of the design and validation of such assessments. The present article presents a framework for conceptualizing and organizing the multiple…
United States-China-India Relationship: An Analysis of the Emergence of a Strategic Triangle

DTIC Science & Technology

2007-12-14

rules of rational play. The shift from one pattern dynamic to another is a function of the attempts of the players to freeze a given configuration...It seeks only modest or no change in the international system (the relative power status of the major states, the rules governing interaction...
46 CFR 58.30-5 - Design requirements.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 2 2010-10-01 2010-10-01 false Design requirements. 58.30-5 Section 58.30-5 Shipping... AND RELATED SYSTEMS Fluid Power and Control Systems § 58.30-5 Design requirements. (a) The.... (b) The system shall be so designed that proper functioning of any unit shall not be affected by the...
46 CFR 58.30-5 - Design requirements.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 2 2011-10-01 2011-10-01 false Design requirements. 58.30-5 Section 58.30-5 Shipping... AND RELATED SYSTEMS Fluid Power and Control Systems § 58.30-5 Design requirements. (a) The.... (b) The system shall be so designed that proper functioning of any unit shall not be affected by the...
The Council of Europe's "Common European Framework of Reference for Languages" (CEFR): Approach, Status, Function and Use

ERIC Educational Resources Information Center

Martyniuk, Waldemar

2012-01-01

The Council of Europe's "Common European Framework of Reference for Languages" is rapidly becoming a powerful instrument for shaping language education policies in Europe and beyond. The task of relating language policies, language curricula, teacher education and training, textbook and course design and content, examinations and…

Classroom Remix: Patterns of Pedagogy in a Techno-Literacies Poetry Unit

ERIC Educational Resources Information Center

Callahan, Meg; King, Jennifer M.

2011-01-01

Researchers collaborated with two high school creative writing teachers to consider how a particular use of technology--PowerPoint poetry interpretations--would function in their creative writing classes. Their findings encouraged them to consider three kinds of "classroom remix" related to the introduction of techno-literacy practices into the…
A Simple Experiment Demonstrating the Relationship between Response Curves and Absorption Spectra.

ERIC Educational Resources Information Center

Li, Chia-yu

1984-01-01

Describes an experiment for recording two individual spectrophotometer response curves. The two curves are directly related to the power of transmitted beams that pass through a solvent and solution. An absorption spectrum of the solution can be constructed from the calculated rations of the curves as a function of wavelength. (JN)
"The Tempest": A Negotiable Meta-Panopticon

ERIC Educational Resources Information Center

Motlagh, Hanieh Mehr

2015-01-01

In "The Tempest", Shakespeare represents a world in which the model of a panopticon within a panopticon reveals how the power relations functions. All the major and minor characters establish panopticons which start from their own bodies and soul and move toward the larger one which belongs to that of Prospero as the higher order who has…
Synthesis and analysis of discriminators under influence of broadband non-Gaussian noise

NASA Astrophysics Data System (ADS)

Artyushenko, V. M.; Volovach, V. I.

2018-01-01

We considered the problems of the synthesis and analysis of discriminators, when the useful signal is exposed to non-Gaussian additive broadband noise. It is shown that in this case, the discriminator of the tracking meter should contain the nonlinear transformation unit, the characteristics of which are determined by the Fisher information relative to the probability density function of the mixture of non-Gaussian broadband noise and mismatch errors. The parameters of the discriminatory and phase characteristics of the discriminators working under the above conditions are obtained. It is shown that the efficiency of non-linear processing depends on the ratio of power of FM noise to the power of Gaussian noise. The analysis of the information loss of signal transformation caused by the linear section of discriminatory characteristics of the unit of nonlinear transformations of the discriminator is carried out. It is shown that the average slope of the nonlinear transformation characteristic is determined by the Fisher information relative to the probability density function of the mixture of non-Gaussian noise and mismatch errors.
Characteristics of Nd:YAG sculptured contact probes after prolonged laser application.

PubMed

Barroso, E G; Haklin, M F; Staren, E D

1995-01-01

This study analyzed the functional and structural characteristics of cone, hemisphere, and modified sculptured contact fibers (1,000 microns) after 1 hour of continuous Nd:YAG laser application. Continuous laser application was performed on live porcine tissue using 20 watts of power. The fiber's appearance under a microscope as well as the power output was recorded after 0, 5, 10, 20, 30, 45, and 60 minutes of continuous laser application. (N = 3 for each fiber). At time 0, all fibers transmitted from 49 to 56% of the initial 20 watts (W); power transmission decreased to less than 9% relative power transmission after 20 minutes and then plateaued. The fibers exhibited severe distortion and carbonization of the surface where laser had been applied with evidence of quartz melting and shattering after only 10 minutes. By 30 minutes of laser application, all three fibers were fractured and essentially indistinguishable from one another; moreover, the fibers exhibited similar power transmission, and cutting and coagulation activity, as determined by a panel of independent, double-blinded surgeons. These data lead us to conclude that 1) Nd:YAG contact laser effects result from thermal heating of the fiber tip with subsequent tissue injury, 2) the unique structural configuration of the fiber's sculptured tip are lost after several minutes of laser application without appreciable change in functional integrity, and 3) fibers may be manually fractured allowing for multiple uses without significant sacrifice of power transmission or surgical utility.
A relational framework for understanding bullying: Developmental antecedents and outcomes.

PubMed

Rodkin, Philip C; Espelage, Dorothy L; Hanish, Laura D

2015-01-01

This article reviews current research on the relational processes involved in peer bullying, considering developmental antecedents and long-term consequences. The following themes are highlighted: (a) aggression can be both adaptive and maladaptive, and this distinction has implications for bullies' functioning within peer social ecologies; (b) developmental antecedents and long-term consequences of bullying have not been well-distinguished from the extant research on aggressive behavior; (c) bullying is aggression that operates within relationships of power and abuse. Power asymmetry and repetition elements of traditional bullying definitions have been hard to operationalize, but without these specifications and more dyadic measurement approaches there may be little rationale for a distinct literature on bullying--separate from aggression. Applications of a relational approach to bullying are provided using gender as an example. Implications for future research are drawn from the study of relationships and interpersonal theories of developmental psychopathology. (c) 2015 APA, all rights reserved).
The Division of Household Labor: Longitudinal Changes and Within-Couple Variation.

PubMed

Lam, Chun Bun; McHale, Susan M; Crouter, Ann C

2012-10-01

This study examined how the division of household labor changed as a function of marital duration and whether within-couple variation in spouses' relative power and availability were linked to within-couple variation in the division of labor. On 4 occasions over 7 years, 188 stably married couples reported on their housework activities using daily diaries. Multilevel models revealed that wives' portions of household responsibilities declined over time, and that changes in spouses' relative income and work hours were linked to changes in housework allocation. Wives with husbands who perceived greater marital control, on average, did proportionally more housework, and for couples with husbands who had highly autonomous jobs, changes in spouses' relative psychological job involvement were linked to changes in housework allocation. Findings highlight the importance of understanding household division of labor as a lifespan phenomenon, the distinction between within- versus between-couple associations, and the multidimensional nature of power and availability.
Effects of a 12-week marching in place and chair rise daily exercise intervention on ADL and functional mobility in frail older adults.

PubMed

Kato, Yoshiji; Islam, Mohammod M; Koizumi, Daisuke; Rogers, Michael E; Takeshima, Nobuo

2018-04-01

[Purpose] To determine the effects of a 12-week intervention consisting of marching in place and chair rising daily exercise on activities of daily living and functional mobility (ability to quickly rise from a chair and walk) in frail older adults. [Subjects and Methods] Thirty-one participants were divided into exercise (n=18, age=77.6 ± 7.2 years; 11 males, 7 females) and non-exercise (n=13, age=79.6 ± 7.7 years; 7 males, 6 females) groups. The exercise group performed 12 weeks of training, 7 days per week, and 20 minutes per session. The exercise program consisted of low to moderate intensity marching in place and chair rising movements. The speed of movements was gradually increased over time. The Barthel index, mean power during chair stand, and time to complete a 10-m walk were assessed before and after the intervention. [Results] Significant improvements were noted in the exercise group compared to the non-exercise group for the Barthel Index (11.6%), mean power (33%), and 10-M walk (14.6%) with a medium effect size, and relative mean power (power/body mass) (32.9%) with a large effect size. [Conclusion] The progressive marching in place and chair rising exercise intervention appears to be effective in improving activities of daily living and functional mobility among frail older adults.
Reconciling Particle-Beam and Optical Stopping-Power Measurements in Silicon

NASA Astrophysics Data System (ADS)

Karstens, William; Shiles, E. J.; Smith, David Y.

A swift, charged particle passing through matter loses energy to electronic excitations via the electro-magnetic transients experienced by atoms along its path. Bethe related this process to the matter's frequency-dependent dielectric function ɛ (ℏω) through the energy-loss function, Im[-1/ ɛ (ℏω) ]. The matter's response may be summarized by a single parameter, the mean excitation energy, or I value, that combines the optical excitation spectrum and excitation probability. Formally, ln I is the mean of ln ℏω weighted by the energy-loss function. This provides an independent optical check on particle energy-loss experiments. However, a persistent disagreement is found for silicon: direct particle-beam studies yield 173.5< I<176 eV, but a fit to the stopping-power of 36 elements suggests 165 eV. An independent determination from optical data in 1986 gave 174 eV supporting the higher values. However, recent x-ray measurements disclosed short comings in the 1986 optical data: 1. Measurements by Ershov and Lukirskii underestimated the L-edge strength, and 2. A power-law extrapolation overestimated the K-edge strength. We have updated these data and find I = 162 eV, suggesting that silicon's recommended I value should be reconsidered. While this 5% change in I value changes the stopping power by only 1%, it is significant for precision measurements with Si detectors. Supported in part by the US Department of Energy, Office of Science, Office of Nuclear Physics under Contract DE-AC02-06CH11357.
Gender, status and 'powerless' speech: interactions of students and lecturers.

PubMed

McFadyen, R G

1996-09-01

The present study investigated whether the use of 'powerless' speech was affected by role status, speaker's gender and gender of another participant. Fifty-two university lecturers and 156 students participated. Students were paired with a lecturer or student of the same or opposite sex. The findings placed a question mark over the link between powerless speech and individuals of low role status. Moreover, against hypothesis, speaker's gender and gender of partner did not affect the use of qualifiers or fillers, although they affected the use of tag questions and some types of hesitation. A qualitative analysis was also conducted which suggested that the powerless features were, in fact, multi-functional with respect to power. In addition, the importance of a variety of interactional techniques, such as credibility techniques, in the creation or negotiation of relational power was documented. As a whole, these findings highlight problems with the concept of 'powerless' speech, at least with respect to relational power.
Propulsion requirements for communications satellites.

NASA Technical Reports Server (NTRS)

Isley, W. C.; Duck, K. I.

1972-01-01

The concept of characteristics thrust is introduced herein as a means of classifying propulsion system tasks related particularly to geosynchronous communications spacecraft. Approximate analytical models are developed to permit estimation of characteristic thrust for injection error corrections, orbit angle re-location, north-south station keeping, east-west station keeping, spin axis precession control, attitude rate damping, and orbit raising applications. Performance assessment factors are then outlined in terms of characteristic power, characteristic weight, and characteristic volume envelope, which are related to the characteristic thrust. Finally, selected performance curves are shown for power as a function of spacecraft weight, including the influence of duty cycle on north-south station keeping, a 90 degree orbit angle re-location in 14 days, and finally comparison of orbit raising tasks from low and intermediate orbits to a final geosynchronous station. Power requirements range from less than 75 watts for north-south station keeping on small payloads up to greater than 15 KW for a 180 day orbit raising mission including a 28.5 degree plane change.
The dimensioning and development of hospital electric installations to guarantee the continuity of use of the therapeutic and diagnostic system.

PubMed

Stroili, M; Pavan, E C; Gorela, M; Kenda, F

2015-08-01

The Technical Services and the Medical Administration of the Hospitals of Trieste have been working for years to ensure the optimal functioning of the Medicine, Surgery, Diagnostics and Research services offered to the Patients and to the University in an 800-bed hospital complex, transforming and innovating the buildings and support installations. We have dedicated special attention to the technologies necessary to guarantee the continuity of the power supply to the electromedical devices, increasingly numerous in highly specialized hospitals. We report our electricity consumption and the power of the generator sets and the UPS and our opinion that their power must be related to the overall consumption of the Hospital, with a reserve margin.
A characterization of persistence at short times in the WFC3/IR detector

NASA Astrophysics Data System (ADS)

Gennaro, M.; Bajaj, V.; Long, K.

2018-05-01

Persistence in the WFC3/IR detector appears to decay as a power law as a function of time elapsed since the end of a stimulus. In this report we study departures from the power law at times shorter than a few hundreds seconds after the stimulus. In order to have better short-time cadence, we use the Multiaccum (.ima) files, which trace the accumulated charge in the pixels as function of time, rather than the final pipeline products (.flt files), which instead report the electron rate estimated via a linear fit to the accumulated charge vs. time relation. We note that at short times after the stimulus, the absolute change in persistence is the strongest, thus a linear fit to the accumulated signal (the .flt values) can be a poor representation of the strongly varying persistence signal. The already observed power-law decay of the persistence signal, still holds at shorter times, with typical values of the power law index, gamma in [-0.8,-1] for stimuli that saturate the WFC3 pixels. To a good degree of approximation, a single power law is a good fit to the persistence signal decay from 100 to 5000 seconds. We also detect a tapering-off in the power-law decay at increasingly shorter times. This change in behavior is of the order of Delta Gamma 0.02 - 0.05 when comparing power-law fits performed to the persistence signal from 0 up to 250 seconds and from 0 up to 4000 seconds after the stimulus, indicating that persistence decays slightly more rapidly as time progresses. Our results may suggest that for even shorter times, not probed by our study, the WFC3 persistence signal might deviate from a single power-law model.
Size matters: abundance matching, galaxy sizes, and the Tully-Fisher relation in EAGLE

NASA Astrophysics Data System (ADS)

Ferrero, Ismael; Navarro, Julio F.; Abadi, Mario G.; Sales, Laura V.; Bower, Richard G.; Crain, Robert A.; Frenk, Carlos S.; Schaller, Matthieu; Schaye, Joop; Theuns, Tom

2017-02-01

The Tully-Fisher relation (TFR) links the stellar mass of a disc galaxy, Mstr, to its rotation speed: it is well approximated by a power law, shows little scatter, and evolves weakly with redshift. The relation has been interpreted as reflecting the mass-velocity scaling (M ∝ V3) of dark matter haloes, but this interpretation has been called into question by abundance-matching (AM) models, which predict the galaxy-halo mass relation to deviate substantially from a single power law and to evolve rapidly with redshift. We study the TFR of luminous spirals and its relation to AM using the EAGLE set of Λ cold dark matter (ΛCDM) cosmological simulations. Matching both relations requires disc sizes to satisfy constraints given by the concentration of haloes and their response to galaxy assembly. EAGLE galaxies approximately match these constraints and show a tight mass-velocity scaling that compares favourably with the observed TFR. The TFR is degenerate to changes in galaxy formation efficiency and the mass-size relation; simulations that fail to match the galaxy stellar mass function may fit the observed TFR if galaxies follow a different mass-size relation. The small scatter in the simulated TFR results because, at fixed halo mass, galaxy mass and rotation speed correlate strongly, scattering galaxies along the main relation. EAGLE galaxies evolve with lookback time following approximately the prescriptions of AM models and the observed mass-size relation of bright spirals, leading to a weak TFR evolution consistent with observation out to z = 1. ΛCDM models that match both the abundance and size of galaxies as a function of stellar mass have no difficulty reproducing the observed TFR and its evolution.
A distributed microcomputer-controlled system for data acquisition and power spectral analysis of EEG.

PubMed

Vo, T D; Dwyer, G; Szeto, H H

1986-04-01

A relatively powerful and inexpensive microcomputer-based system for the spectral analysis of the EEG is presented. High resolution and speed is achieved with the use of recently available large-scale integrated circuit technology with enhanced functionality (INTEL Math co-processors 8087) which can perform transcendental functions rapidly. The versatility of the system is achieved with a hardware organization that has distributed data acquisition capability performed by the use of a microprocessor-based analog to digital converter with large resident memory (Cyborg ISAAC-2000). Compiled BASIC programs and assembly language subroutines perform on-line or off-line the fast Fourier transform and spectral analysis of the EEG which is stored as soft as well as hard copy. Some results obtained from test application of the entire system in animal studies are presented.
Persistent topographic quantitative EEG sequelae of chronic marihuana use: a replication study and initial discriminant function analysis.

PubMed

Struve, F A; Straumanis, J J; Patrick, G

1994-04-01

In a previous pilot study using psychiatric patients we reported that daily marihuana users had significant elevations of (1) Absolute Alpha Power, (2) Relative Alpha Power, and (3) Interhemispheric Alpha Coherence over both frontal and frontal-central areas when contrasted with subjects who did not use marihuana. We referred to this phenomenon as Hyperfrontality of Alpha. The study presented here is a successful replication of our previous findings using new samples of subjects and identical methods. Post hoc analyses based on the combined sample from both studies suggest that variables of psychiatric diagnoses and medication did not bias our results. In addition, a discriminant function analysis using quantitative EEG variables as candidate predictors generated a 95% correct THC user versus nonuser classification accuracy which received a successful jackknife replication.
Materials-related issues in the safety and licensing of nuclear fusion facilities

NASA Astrophysics Data System (ADS)

Taylor, N.; Merrill, B.; Cadwallader, L.; Di Pace, L.; El-Guebaly, L.; Humrickhouse, P.; Panayotov, D.; Pinna, T.; Porfiri, M.-T.; Reyes, S.; Shimada, M.; Willms, S.

2017-09-01

Fusion power holds the promise of electricity production with a high degree of safety and low environmental impact. Favourable characteristics of fusion as an energy source provide the potential for this very good safety and environmental performance. But to fully realize the potential, attention must be paid in the design of a demonstration fusion power plant (DEMO) or a commercial power plant to minimize the radiological hazards. These hazards arise principally from the inventory of tritium and from materials that become activated by neutrons from the plasma. The confinement of these radioactive substances, and prevention of radiation exposure, are the primary goals of the safety approach for fusion, in order to minimize the potential for harm to personnel, the public, and the environment. The safety functions that are implemented in the design to achieve these goals are dependent on the performance of a range of materials. Degradation of the properties of materials can lead to challenges to key safety functions such as confinement. In this paper the principal types of material that have some role in safety are recalled. These either represent a potential source of hazard or contribute to the amelioration of hazards; in each case the related issues are reviewed. The resolution of these issues lead, in some instances, to requirements on materials specifications or to limits on their performance.
Functional and antioxidant properties of protein hydrolysates obtained from white shrimp (Litopenaeus vannamei).

PubMed

Latorres, J M; Rios, D G; Saggiomo, G; Wasielesky, W; Prentice-Hernandez, C

2018-02-01

Protein hydrolysates from white shrimp ( Litopenaeus vannamei ) with different degrees of hydrolysis (DH-10 and 20%) were prepared using the enzymes Alcalase 2.4 L and Protamex. The hydrolysates were evaluated for amino acid composition, solubility, foaming properties, emulsifying and antioxidant activity. All the hydrolysates showed high concentrations of Glutamic Acid, Aspartic acid, Arginine, Glycine, Lysine, Proline. It was found that the increase in the production of negatively charged amino acids was related to increase in DH. The hydrophobic amino acids were higher for hydrolysates obtained with Alcalase (10% DH) and Protamex (20% DH). The results indicated that higher degree of hydrolysis showed positive relation with the protein solubility of the hydrolysates, while negatively influenced foam and emulsification properties. The antioxidant properties presented by the white shrimp protein hydrolysates were influenced by the composition and peptides size. Hydrolysates with higher peptide chain showed the highest antioxidant power for the 2,2-Diphenyl-1-picrylhydrazyl radical scavenging and reducing power, while hydrolysates with lower peptide chain showed higher antioxidant power for 2,2'-azinobis (3-ethylbenzothiazoline sulfonic acid) radical scavenging. All hydrolysates showed dose-dependent antioxidant activities. Therefore, the results of the present study suggest that white shrimp is a potential source of protein hydrolysates as bioactive ingredients for the use in the formulation of functional foods as well as natural antioxidants in lipid food systems.
Jump-Squat and Half-Squat Exercises: Selective Influences on Speed-Power Performance of Elite Rugby Sevens Players

PubMed Central

Loturco, Irineu; Pereira, Lucas A.; Moraes, José E.; Kitamura, Katia; Cal Abad, César C.; Kobal, Ronaldo; Nakamura, Fábio Y.

2017-01-01

The aim of this study was to evaluate the relation between the maximum mean propulsive power (MPP) obtained in the loaded jump squat (JS) and half squat (HS) exercises and functional performances in vertical jumps, 40 m linear speed (VEL) and change-of-direction (COD) tests, using the median split technique. Twenty-two male rugby sevens players from the Brazilian National Olympic Team (Rio-2016) performed vertical jumping tests (squat and countermovement jumps [SJ and CMJ]), JS and HS exercises, COD speed test and sprinting velocity in 40 m, in this order. Based on the results of the MPP in the JS and HS exercises the participants were divided, using the median split, into four groups as follows: higher JS, lower JS, higher HS, and lower HS. Between-group differences in the functional tasks were detected via magnitude-based inferences. The athletes with higher MPP in the JS were capable of jumping higher and sprinting faster (including the COD speed test) than their weaker counterparts. This pattern was not observed in the HS exercise. To conclude, JS was shown to be more connected to sprinting, COD speed and jumping abilities than HS in elite rugby sevens players and should be preferred for assessing and possibly training elite athletes needing to improve speed-power related abilities. PMID:28114431
Jump-Squat and Half-Squat Exercises: Selective Influences on Speed-Power Performance of Elite Rugby Sevens Players.

PubMed

Loturco, Irineu; Pereira, Lucas A; Moraes, José E; Kitamura, Katia; Cal Abad, César C; Kobal, Ronaldo; Nakamura, Fábio Y

2017-01-01

The aim of this study was to evaluate the relation between the maximum mean propulsive power (MPP) obtained in the loaded jump squat (JS) and half squat (HS) exercises and functional performances in vertical jumps, 40 m linear speed (VEL) and change-of-direction (COD) tests, using the median split technique. Twenty-two male rugby sevens players from the Brazilian National Olympic Team (Rio-2016) performed vertical jumping tests (squat and countermovement jumps [SJ and CMJ]), JS and HS exercises, COD speed test and sprinting velocity in 40 m, in this order. Based on the results of the MPP in the JS and HS exercises the participants were divided, using the median split, into four groups as follows: higher JS, lower JS, higher HS, and lower HS. Between-group differences in the functional tasks were detected via magnitude-based inferences. The athletes with higher MPP in the JS were capable of jumping higher and sprinting faster (including the COD speed test) than their weaker counterparts. This pattern was not observed in the HS exercise. To conclude, JS was shown to be more connected to sprinting, COD speed and jumping abilities than HS in elite rugby sevens players and should be preferred for assessing and possibly training elite athletes needing to improve speed-power related abilities.

The assessment of health impacts and external costs of natural gas-fired power plant of Qom.

PubMed

Fouladi Fard, Reza; Naddafi, Kazem; Yunesian, Masud; Nabizadeh Nodehi, Ramin; Dehghani, Mohammad Hadi; Hassanvand, Mohammad Sadegh

2016-10-01

The external health damage costs of the combined cycle natural gas-fired power plant of Qom were investigated via the simplified impact pathway approach. Emitted particulate matter (PM 10 ) and gaseous pollutants (NO x , CO, and SO 2 ) from the power plant stack were measured The health effects and related costs were estimated by QUERI model from AirPacts according to the emissions, source and stack parameters, pollutant depletion velocities, exposure-response functions, local and regional population density, and detailed meteorological data. The results showed that the main health effect was assigned to the nitrate as restricted activity days (RAD) with 25,240 days/year. For all pollutants, the maximum health damage costs were related to the long-term mortality (49 %), restricted activity days (27 %), and chronic bronchitis (21 %). The annual health damage costs were approximately 4.76 million US$, with the cost being 0.096 US per kWh of generating electricity. Although the health damage costs of gas-fired power plant were lower than those of other heavy fuels, it seems essential to consider the health and environmental damages and focus on the emission control strategies, particularly in site selection for the new power plants and expanding the current ones.
Overview of condition monitoring and operation control of electric power conversion systems in direct-drive wind turbines under faults

NASA Astrophysics Data System (ADS)

Huang, Shoudao; Wu, Xuan; Liu, Xiao; Gao, Jian; He, Yunze

2017-09-01

Electric power conversion system (EPCS), which consists of a generator and power converter, is one of the most important subsystems in a direct-drive wind turbine (DD-WT). However, this component accounts for the most failures (approximately 60% of the total number) in the entire DD-WT system according to statistical data. To improve the reliability of EPCSs and reduce the operation and maintenance cost of DD-WTs, numerous researchers have studied condition monitoring (CM) and fault diagnostics (FD). Numerous CM and FD techniques, which have respective advantages and disadvantages, have emerged. This paper provides an overview of the CM, FD, and operation control of EPCSs in DD-WTs under faults. After introducing the functional principle and structure of EPCS, this survey discusses the common failures in wind generators and power converters; briefly reviewed CM and FD methods and operation control of these generators and power converters under faults; and discussed the grid voltage faults related to EPCSs in DD-WTs. These theories and their related technical concepts are systematically discussed. Finally, predicted development trends are presented. The paper provides a valuable reference for developing service quality evaluation methods and fault operation control systems to achieve high-performance and high-intelligence DD-WTs.
PHYSICAL THERAPY INTERVENTION FOR A FORMER POWER LIFTER AFTER ARTHROSCOPIC MICROFRACTURE PROCEDURE FOR GRADE IV GLENOHUMERAL CHONDRAL DEFECTS

PubMed Central

Sum, Jonathan

2011-01-01

Background: Power lifting places the shoulder complex at risk for injury. Microfracture is a relatively new procedure for chondral defects of the glenohumeral joint and is not well described in the literature. Objectives: The purpose of this case report is to describe the post-operative rehabilitation used with a power lifter who underwent a microfracture procedure to address glenoid and humeral chondral defects, debridement of type I superior labral anterior-posterior lesion, and a subacromial decompression. Case Description: The patient was a 46 year-old male who was evaluated nine weeks status-post arthroscopic microfracture procedure for glenoid and humeral chondral defects, debridement of superior labral anterior-posterior (SLAP) lesion, and subacromial decompression. Rehabilitation consisted of postural education, manual therapy, rotator cuff and scapular strengthening, dynamic stabilization, weightbearing exercises, and weight training over nine weeks (24 sessions). Lifting modifications were addressed. Outcomes: Results of the QuickDASH indicate that activities of daily living (ADLs), work, and sports modules all improved significantly, and the patient was able to return to recreational power lifting with limited discomfort or restrictions. Discussion: A structured post-operative physical therapy treatment program allowed this patient to return to recreational power lifting while restoring independent function for work-related activities and ADLs. PMID:21655454
Stopping power and range calculations in human tissues by using the Hartree-Fock-Roothaan wave functions

NASA Astrophysics Data System (ADS)

Usta, Metin; Tufan, Mustafa Çağatay

2017-11-01

The object of this work is to present the consequences for the stopping power and range values of some human tissues at energies ranging from 1 MeV to 1 GeV and 1-500 MeV, respectively. The considered human tissues are lung, intestine, skin, larynx, breast, bladder, prostate and ovary. In this work, the stopping power is calculated by considering the number of velocity-dependent effective charge and effective mean excitation energies of the target material. We used the Hartree-Fock-Roothaan (HFR) atomic wave function to determine the charge density and the continuous slowing down approximation (CSDA) method for the calculation of the proton range. Electronic stopping power values of tissues results have been compared with the ICRU 44, 46 reports, SRIM, Janni and CasP data over the percent error rate. Range values relate to tissues have compared the range results with the SRIM, FLUKA and Geant4 data. For electronic stopping power results, ICRU, SRIM and Janni's data indicated the best fit with our values at 1-50, 50-250 MeV and 250 MeV-1 GeV, respectively. For range results, the best accordance with the calculated values have been found the SRIM data and the error level is less than 10% in proton therapy. However, greater 30% errors were observed in the 250 MeV and over energies.
The effects of habitat management on the species, phylogenetic and functional diversity of bees are modified by the environmental context.

PubMed

Sydenham, Markus A K; Moe, Stein R; Stanescu-Yadav, Diana N; Totland, Ørjan; Eldegard, Katrine

2016-02-01

Anthropogenic landscape elements, such as roadsides, hedgerows, field edges, and power line clearings, can be managed to provide important habitats for wild bees. However, the effects of habitat improvement schemes in power line clearings on components of diversity are poorly studied. We conducted a large-scale experiment to test the effects of different management practices on the species, phylogenetic, and functional diversity of wild bees in power line clearings (n = 19 sites across southeastern Norway) and explored whether any treatment effects were modified by the environmental context. At each site, we conducted the following treatments: (1) Cut: all trees cut and left to decay in the clearing; (2) Cut + Remove: all trees cut and removed from the plot; and (3) Uncut: uncleared. The site-specific environmental context (i.e., elevation and floral diversity) influenced the species, phylogenetic, and functional diversity within bee species assemblages. The largest number of species was found in the Cut + Remove treatment in plots with a high forb species richness, indicating that the outcome of management practices depends on the environmental context. Clearing of treatment plots with many forb species also appeared to alter the phylogenetic composition of bee species assemblages, that is, more closely related species were found in the Cut and the Cut + Remove plots than in the Uncut plots. Synthesis and applications: Our experimental simulation of management practices in power line clearings influenced the species, phylogenetic, and functional diversity of bee species assemblages. Frequent clearing and removal of the woody debris at low elevations with a high forb species richness can increase the value of power line clearings for solitary bees. It is therefore important for managers to consider the environmental context when designing habitat improvement schemes for solitary bees.
Multipartite entanglement indicators based on monogamy relations of n-qubit symmetric states

PubMed Central

Liu, Feng; Gao, Fei; Qin, Su-Juan; Xie, Shu-Cui; Wen, Qiao-Yan

2016-01-01

Constructed from Bai-Xu-Wang-class monogamy relations, multipartite entanglement indicators can detect the entanglement not stored in pairs of the focus particle and the other subset of particles. We investigate the k-partite entanglement indicators related to the αth power of entanglement of formation (αEoF) for k ≤ n, αϵ and n-qubit symmetric states. We then show that (1) The indicator based on αEoF is a monotonically increasing function of k. (2) When n is large enough, the indicator based on αEoF is a monotonically decreasing function of α, and then the n-partite indicator based on works best. However, the indicator based on 2 EoF works better when n is small enough. PMID:26842264
Multipartite entanglement indicators based on monogamy relations of n-qubit symmetric states.

PubMed

Liu, Feng; Gao, Fei; Qin, Su-Juan; Xie, Shu-Cui; Wen, Qiao-Yan

2016-02-04

Constructed from Bai-Xu-Wang-class monogamy relations, multipartite entanglement indicators can detect the entanglement not stored in pairs of the focus particle and the other subset of particles. We investigate the k-partite entanglement indicators related to the αth power of entanglement of formation (αEoF) for k ≤ n, αϵ and n-qubit symmetric states. We then show that (1) The indicator based on αEoF is a monotonically increasing function of k. (2) When n is large enough, the indicator based on αEoF is a monotonically decreasing function of α, and then the n-partite indicator based on works best. However, the indicator based on 2 EoF works better when n is small enough.
Multipartite entanglement indicators based on monogamy relations of n-qubit symmetric states

NASA Astrophysics Data System (ADS)

Liu, Feng; Gao, Fei; Qin, Su-Juan; Xie, Shu-Cui; Wen, Qiao-Yan

2016-02-01

Constructed from Bai-Xu-Wang-class monogamy relations, multipartite entanglement indicators can detect the entanglement not stored in pairs of the focus particle and the other subset of particles. We investigate the k-partite entanglement indicators related to the αth power of entanglement of formation (αEoF) for k ≤ n, αɛ and n-qubit symmetric states. We then show that (1) The indicator based on αEoF is a monotonically increasing function of k. (2) When n is large enough, the indicator based on αEoF is a monotonically decreasing function of α, and then the n-partite indicator based on works best. However, the indicator based on 2 EoF works better when n is small enough.
Spectral power and functional connectivity changes during mindfulness meditation with eyes open: A magnetoencephalography (MEG) study in long-term meditators.

PubMed

Wong, W P; Camfield, D A; Woods, W; Sarris, J; Pipingas, A

2015-10-01

Whilst a number of previous studies have been conducted in order to investigate functional brain changes associated with eyes-closed meditation techniques, there is a relative scarcity in the literature with regards to changes occurring during eyes-open meditation. The current project used magnetoencephalography (MEG) to investigate differences in spectral power and functional connectivity between 11 long-term mindfulness meditators (LTMMs) with >5 years of experience and 12 meditation-naïve control participants both during baseline eyes-open rest and eyes-open open-monitoring (OM) mindfulness meditation. During resting with eyes-open, prior to meditating, greater mean alpha power was observed for LTMMs in comparison to controls. However, during the course of OM meditation, a significantly greater increase in theta power was observed over a broad fronto-centro-parietal region for control participants in comparison to LTMMs. In contrast, whole-head mean connectivity was found to be significantly greater for long-term meditators in comparison to controls in the theta band both during rest as well as during meditation. Additionally, mean connectivity was significantly lower for long-term meditators in the low gamma band during rest and significantly lower in both low and high gamma bands during meditation; and the variance of low-gamma connectivity scores for long-term meditators was significantly decreased compared to the control group. The current study provides important new information as to the trait functional changes in brain activity associated with long-term mindfulness meditation, as well as the state changes specifically associated with eyes-open open monitoring meditation techniques. Copyright © 2015 Elsevier B.V. All rights reserved.
Geomorphic versus land use controls on suspended sediment rating curves

NASA Astrophysics Data System (ADS)

Belmont, P.; Vaughan, A. A.; Fisher, A. C. N.

2017-12-01

The relation between river discharge (Q) and suspended sediment (SS) concentration reflects the degree to which sediment sources are accessed or depleted across the range of flow conditions. Increased availability of high resolution topography and land use data greatly enhance our ability to evaluate linkages between characteristics of these sediment rating curves (SRCs) and the geomorphic features that influence them. We evaluated Q-SS relations at 45 gages throughout Minnesota, USA representing a wide variety of landscape settings in terms of topography, land use, and geologic history. We characterized the SRCs according to the overall shape, steepness (exponent), vertical offset (coefficient) and SS concentration under low flow (90% exceedance) conditions. Rivers exhibited three distinct SRC shapes, simple power functions, threshold power functions and peaked power functions. We used random forest models to analyze relations between SRC parameters and attributes of the watershed as well as the near-channel environment. The model correctly classified 78% of SRC shapes and explained 60% of variance in the SRC exponent, 43% of the SRC coefficient for rising limb samples, and 45% of variance under low flow conditions. Notably, the random forest models predict that near-channel morphology predominately controls both the shape and steepness of the sediment rating curves. Land use predominately controls the vertical offset (coefficient) and SS concentration under low flow conditions. These findings suggest that land use and watershed restoration practices may have little capacity to alter the shape and steepness of these curves as these characteristics may be dictated by the geologic and geomorphic setting. Rather, human influences in the watershed may exhibit the greatest influence on suspended sediment concentrations at moderate to low flows. Criteria to evaluate improvements in water quality as a result of changes in land management might be most meaningful if they target these moderate to low flow conditions.
Reduced anaerobic and aerobic performance in children with primary ciliary dyskinesia.

PubMed

Simsek, Senem; Inal-Ince, Deniz; Cakmak, Aslihan; Emiralioglu, Nagehan; Calik-Kutukcu, Ebru; Saglam, Melda; Vardar-Yagli, Naciye; Ozcelik, Hayriye Ugur; Sonbahar-Ulu, Hazal; Bozdemir-Ozel, Cemile; Kiper, Nural; Arikan, Hulya

2018-05-01

Primary ciliary dyskinesia (PCD) restricts lifestyle and increases morbidity. The aim of the study was to investigate anaerobic and aerobic performance in children with PCD and their healthy counterparts. Thirty-one children with PCD and 29 age- and sex-matched healthy subjects were studied. Pulmonary function, hand grip strength (HGS), quadriceps strength (QMS), physical activity, anaerobic capacity (muscle power sprint test), and aerobic performance (modified shuttle walk test (MSWT)) were determined. Pulmonary function, HGS, QMS, mean anaerobic power (MAP), and MSWT distance in PCD were significantly lower than those of healthy subjects (p < 0.05). In PCD, the MAP was significantly correlated with age, FEV 1 , and the mean kcal for 3 days (p < 0.05), and age was its independent predictor (p < 0.05). The MSWT distance was significantly related to gender and weight (p < 0.05), and gender was selected as its independent predictor (p < 0.05). In healthy controls, the MAP was significantly associated with age, gender, FVC, FEV 1 , HGS, QMS, and the mean kcal for three days (p < 0.05). The MSWT distance was significantly related to weight and body mass index in healthy group (p < 0.05). Anaerobic and aerobic performance is impaired in PCD from the early stages. Age determines anaerobic performance. Gender is the determinant of aerobic performance. Whether skeletal muscle characteristics and sex-related changes in body composition affect anaerobic and aerobic capacity in PCD children warrants further study. What is Known: • Exercise performance is determined by anaerobic and aerobic power. • Few studies have shown that PCD patients have lower aerobic performance which is associated with impaired lung function. What is New: • The present research indicated that both anaerobic and aerobic exercise capacity determined using field testing is impaired in PCD from the early stages. • Anaerobic capacity was found to be independently associated with age in PCD. Higher aerobic performance is independently associated with male gender.
Electromagnetic Compatibility Testing Studies

NASA Technical Reports Server (NTRS)

Trost, Thomas F.; Mitra, Atindra K.

1996-01-01

This report discusses the results on analytical models and measurement and simulation of statistical properties from a study of microwave reverberation (mode-stirred) chambers performed at Texas Tech University. Two analytical models of power transfer vs. frequency in a chamber, one for antenna-to-antenna transfer and the other for antenna to D-dot sensor, were experimentally validated in our chamber. Two examples are presented of the measurement and calculation of chamber Q, one for each of the models. Measurements of EM power density validate a theoretical probability distribution on and away from the chamber walls and also yield a distribution with larger standard deviation at frequencies below the range of validity of the theory. Measurements of EM power density at pairs of points which validate a theoretical spatial correlation function on the chamber walls and also yield a correlation function with larger correlation length, R(sub corr), at frequencies below the range of validity of the theory. A numerical simulation, employing a rectangular cavity with a moving wall shows agreement with the measurements. The determination that the lowest frequency at which the theoretical spatial correlation function is valid in our chamber is considerably higher than the lowest frequency recommended by current guidelines for utilizing reverberation chambers in EMC testing. Two suggestions have been made for future studies related to EMC testing.
Working memory performance inversely predicts spontaneous delta and theta-band scaling relations.

PubMed

Euler, Matthew J; Wiltshire, Travis J; Niermeyer, Madison A; Butner, Jonathan E

2016-04-15

Electrophysiological studies have strongly implicated theta-band activity in human working memory processes. Concurrently, work on spontaneous, non-task-related oscillations has revealed the presence of long-range temporal correlations (LRTCs) within sub-bands of the ongoing EEG, and has begun to demonstrate their functional significance. However, few studies have yet assessed the relation of LRTCs (also called scaling relations) to individual differences in cognitive abilities. The present study addressed the intersection of these two literatures by investigating the relation of narrow-band EEG scaling relations to individual differences in working memory ability, with a particular focus on the theta band. Fifty-four healthy adults completed standardized assessments of working memory and separate recordings of their spontaneous, non-task-related EEG. Scaling relations were quantified in each of the five classical EEG frequency bands via the estimation of the Hurst exponent obtained from detrended fluctuation analysis. A multilevel modeling framework was used to characterize the relation of working memory performance to scaling relations as a function of general scalp location in Cartesian space. Overall, results indicated an inverse relationship between both delta and theta scaling relations and working memory ability, which was most prominent at posterior sensors, and was independent of either spatial or individual variability in band-specific power. These findings add to the growing literature demonstrating the relevance of neural LRTCs for understanding brain functioning, and support a construct- and state-dependent view of their functional implications. Copyright © 2016 Elsevier B.V. All rights reserved.
Additive manufacturing technology (direct metal laser sintering) as a novel approach to fabricate functionally graded titanium implants: preliminary investigation of fabrication parameters.

PubMed

Lin, Wei-Shao; Starr, Thomas L; Harris, Bryan T; Zandinejad, Amirali; Morton, Dean

2013-01-01

This article describes the preliminary findings of the mechanical properties of functionally graded titanium with controlled distribution of porosity and a reduced Young's modulus on the basis of a computeraided design (CAD) file, using the rapid-prototyping, direct metal laser sintering (DMLS) technique. Sixty specimens of Ti-6Al-4V were created using a DMLS machine (M270) following the standard for tensile testing of metals. One group was fabricated with only 170 W of laser energy to create fully dense specimens (control group). The remaining specimens all featured an outer fully dense "skin" layer and a partially sintered porous inner "core" region. The outer "skin" of each specimen was scanned at 170 W and set at a thickness of 0.35, 1.00, or 1.50 mm for different specimen groups. The inner "core" of each specimen was scanned at a lower laser power (43 or 85 W). The partially sintered core was clearly visible in all specimens, with somewhat greater porosity with the lower laser power. However, the amount of porosity in the core region was not related to the laser power alone; thinner skin layers resulted in higher porosity for the same power values in the core structure. The lowest Young's modulus achieved, 35 GPa, is close to that of bone and was achieved with a laser power of 43 W and a skin thickness of 0.35 mm, producing a core that comprised 74% of the total volume. Additive manufacturing technology may provide an efficient alternative way to fabricate customized dental implants based on a CAD file with a functionally graded structure that may minimize stress shielding and improve the long-term performance of dental implants.
Theoretical Insight Into the Empirical Tortuosity-Connectivity Factor in the Burdine-Brooks-Corey Water Relative Permeability Model

NASA Astrophysics Data System (ADS)

Ghanbarian, Behzad; Ioannidis, Marios A.; Hunt, Allen G.

2017-12-01

A model commonly applied to the estimation of water relative permeability krw in porous media is the Burdine-Brooks-Corey model, which relies on a simplified picture of pores as a bundle of noninterconnected capillary tubes. In this model, the empirical tortuosity-connectivity factor is assumed to be a power law function of effective saturation with an exponent (μ) commonly set equal to 2 in the literature. Invoking critical path analysis and using percolation theory, we relate the tortuosity-connectivity exponent μ to the critical scaling exponent t of percolation that characterizes the power law behavior of the saturation-dependent electrical conductivity of porous media. We also discuss the cause of the nonuniversality of μ in terms of the nonuniversality of t and compare model estimations with water relative permeability from experiments. The comparison supports determining μ from the electrical conductivity scaling exponent t, but also highlights limitations of the model.
Statistical significance of task related deep brain EEG dynamic changes in the time-frequency domain.

PubMed

Chládek, J; Brázdil, M; Halámek, J; Plešinger, F; Jurák, P

2013-01-01

We present an off-line analysis procedure for exploring brain activity recorded from intra-cerebral electroencephalographic data (SEEG). The objective is to determine the statistical differences between different types of stimulations in the time-frequency domain. The procedure is based on computing relative signal power change and subsequent statistical analysis. An example of characteristic statistically significant event-related de/synchronization (ERD/ERS) detected across different frequency bands following different oddball stimuli is presented. The method is used for off-line functional classification of different brain areas.
Determining the vibrations between sensor and sample in SQUID microscopy

NASA Astrophysics Data System (ADS)

Schiessl, Daniel; Kirtley, John R.; Paulius, Lisa; Rosenberg, Aaron J.; Palmstrom, Johanna C.; Ullah, Rahim R.; Holland, Connor M.; Fung, Y.-K.-K.; Ketchen, Mark B.; Gibson, Gerald W.; Moler, Kathryn A.

2016-12-01

Vibrations can cause noise in scanning probe microscopies. Relative vibrations between the scanning sensor and the sample are important but can be more difficult to determine than absolute vibrations or vibrations relative to the laboratory. We measure the noise spectral density in a scanning SQUID microscope as a function of position near a localized source of magnetic field and show that we can determine the spectra of all three components of the relative sensor-sample vibrations. This method is a powerful tool for diagnosing vibrational noise in scanning microscopies.
A functional U-statistic method for association analysis of sequencing data.

PubMed

Jadhav, Sneha; Tong, Xiaoran; Lu, Qing

2017-11-01

Although sequencing studies hold great promise for uncovering novel variants predisposing to human diseases, the high dimensionality of the sequencing data brings tremendous challenges to data analysis. Moreover, for many complex diseases (e.g., psychiatric disorders) multiple related phenotypes are collected. These phenotypes can be different measurements of an underlying disease, or measurements characterizing multiple related diseases for studying common genetic mechanism. Although jointly analyzing these phenotypes could potentially increase the power of identifying disease-associated genes, the different types of phenotypes pose challenges for association analysis. To address these challenges, we propose a nonparametric method, functional U-statistic method (FU), for multivariate analysis of sequencing data. It first constructs smooth functions from individuals' sequencing data, and then tests the association of these functions with multiple phenotypes by using a U-statistic. The method provides a general framework for analyzing various types of phenotypes (e.g., binary and continuous phenotypes) with unknown distributions. Fitting the genetic variants within a gene using a smoothing function also allows us to capture complexities of gene structure (e.g., linkage disequilibrium, LD), which could potentially increase the power of association analysis. Through simulations, we compared our method to the multivariate outcome score test (MOST), and found that our test attained better performance than MOST. In a real data application, we apply our method to the sequencing data from Minnesota Twin Study (MTS) and found potential associations of several nicotine receptor subunit (CHRN) genes, including CHRNB3, associated with nicotine dependence and/or alcohol dependence. © 2017 WILEY PERIODICALS, INC.
Muscular Strength Is Associated with Higher Intraocular Pressure in Physically Active Males.

PubMed

Vera, Jesús; Jiménez, Raimundo; García-Ramos, Amador; Cárdenas, David

2018-02-01

The positive association between intraocular pressure (IOP) and relative maximum force may have relevance for exercise recommendations when IOP is a concern. The relationship between exercise and IOP has been approached in several studies. However, the influence of muscle function on IOP remains underexplored. This study aimed to determine the relationship between the maximal mechanical capabilities of muscles to generate force, velocity, and power with IOP. Sixty-five physically active males participated in this cross-sectional study. Baseline IOP measures were obtained by rebound tonometry, and participants performed an incremental loading test in the ballistic bench press. Baseline IOP showed a strong positive correlation with relative maximum force (r65 = 0.85, P < .001) relative maximum power (r65 = 0.85, P < .001), and relative one-repetition maximum (r65 = 0.91, P < .001). Also, a moderate positive association was obtained between baseline IOP and maximum force (r65 = 0.74, P < .001), maximum power (r65 = 0.72, P < .001), and maximum dynamic strength (r65 = 0.80, P < .001). No significant correlations between IOP and maximal velocity were obtained (all P > .05). There is a positive association between greater upper-body power and strength with higher baseline IOP, which might have important implications in the management of ocular health and especially in individuals constantly involved in resistance training programs (e.g., military personnel, weightlifters). The possible protective effect of high fitness level on the acute IOP response to strength exercise needs to be addressed in future studies.
Segmentation of the Thalamus Based on BOLD Frequencies Affected in Temporal Lobe Epilepsy

PubMed Central

Morgan, Victoria L.; Rogers, Baxter P.; Abou-Khalil, Bassel

2015-01-01

Objective Temporal lobe epilepsy is associated with functional changes throughout the brain, particularly including a putative seizure propagation network involving the hippocampus, insula and thalamus. We identified a specified frequency range where functional connectivity in this network was related to duration of disease. Then, to identify specific thalamic nuclei involved in seizure propagation, we determined the subregions of the thalamus that have increased resting functional oscillations in this frequency range. Methods Resting-state functional MRI (fMRI) was acquired from twenty unilateral TLE (14 right, 6 left) patients and twenty healthy controls who were each age and gender matched to a specific patient. Wavelet based functional MRI connectivity mapping across the network was computed at each frequency to determine those frequencies where connectivity significantly decreases with duration of disease consistent with impairment due to repeated seizures. The voxel-wise power of the spontaneous blood oxygenation fluctuations of this frequency band was computed in the thalamus of each subject. Results Functional connectivity was impaired in the proposed seizure propagation network over a specific range (0.0067–0.013 Hz and 0.024–0.032 Hz) of blood oxygenation oscillations. Increased power in this frequency band (<0.032 Hz) was detected bilaterally in the pulvinar and anterior nucleus of the thalamus of healthy controls, and was increased over the ipsilateral thalamus compared to the contralateral thalamus in TLE. Significance This study identified frequencies of impaired connectivity in a TLE seizure propagation network and used them to localize the anterior nucleus and pulvinar of the thalamus as subregions most susceptible to TLE seizures. Further examinations of these frequencies in healthy and TLE subjects may provide unique information relating to the mechanism of seizure propagation and potential treatment using electrical stimulation. PMID:26360535

Acoustic radiation from weakly wrinkled premixed flames

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

Lieuwen, Tim; Mohan, Sripathi; Rajaram, Rajesh

2006-01-01

This paper describes a theoretical analysis of acoustic radiation from weakly wrinkled (i.e., u'/S{sub L}<1) premixed flames. Specifically, it determines the transfer function relating the spectrum of the acoustic pressure oscillations, P'({omega}), to that of the turbulent velocity fluctuations in the approach flow, U'({omega}). In the weakly wrinkled limit, this transfer function is local in frequency space; i.e., velocity fluctuations at a frequency {omega} distort the flame and generate sound at the same frequency. This transfer function primarily depends upon the flame Strouhal number St (based on mean flow velocity and flame length) and the correlation length, {lambda}, of themore » flow fluctuations. For cases where the ratio of the correlation length and duct radius {lambda}/a>>1, the acoustic pressure and turbulent velocity power spectra are related by P'({omega})-{omega}{sup 2}U'({omega}) and P'({omega})-U'({omega}) for St<<1 and St>>1, respectively. For cases where {lambda}/a<<1, the transfer functions take the form P'({omega})-{omega}{sup 2}({lambda}/a){sup 2}U'({omega}) and P'({omega})-{omega}{sup 2}({lambda}/a){sup 2}({psi}-{delta}ln({lambda}/a))U'({omega}) for St<<1 and St>>1, respectively, where (PS) and {delta} are constants. The latter result demonstrates that this transfer function does not exhibit a simple power law relationship in the high frequency region of the spectra. The simultaneous dependence of this pressure-velocity transfer function upon the Strouhal number and correlation length suggests a mechanism for the experimentally observed maximum in acoustic spectra and provides some insight into the controversy in the literature over how this peak should scale with the flame Strouhal number.« less
The influence of spatial resolution and smoothing on the detectability of resting-state and task fMRI.

PubMed

Molloy, Erin K; Meyerand, Mary E; Birn, Rasmus M

2014-02-01

Functional MRI blood oxygen level-dependent (BOLD) signal changes can be subtle, motivating the use of imaging parameters and processing strategies that maximize the temporal signal-to-noise ratio (tSNR) and thus the detection power of neuronal activity-induced fluctuations. Previous studies have shown that acquiring data at higher spatial resolutions results in greater percent BOLD signal changes, and furthermore that spatially smoothing higher resolution fMRI data improves tSNR beyond that of data originally acquired at a lower resolution. However, higher resolution images come at the cost of increased acquisition time, and the number of image volumes also influences detectability. The goal of our study is to determine how the detection power of neuronally induced BOLD fluctuations acquired at higher spatial resolutions and then spatially smoothed compares to data acquired at the lower resolutions with the same imaging duration. The number of time points acquired during a given amount of imaging time is a practical consideration given the limited ability of certain populations to lie still in the MRI scanner. We compare acquisitions at three different in-plane spatial resolutions (3.50×3.50mm(2), 2.33×2.33mm(2), 1.75×1.75mm(2)) in terms of their tSNR, contrast-to-noise ratio, and the power to detect both task-related activation and resting-state functional connectivity. The impact of SENSE acceleration, which speeds up acquisition time increasing the number of images collected, is also evaluated. Our results show that after spatially smoothing the data to the same intrinsic resolution, lower resolution acquisitions have a slightly higher detection power of task-activation in some, but not all, brain areas. There were no significant differences in functional connectivity as a function of resolution after smoothing. Similarly, the reduced tSNR of fMRI data acquired with a SENSE factor of 2 is offset by the greater number of images acquired, resulting in few significant differences in detection power of either functional activation or connectivity after spatial smoothing. © 2013.
Independent Orbiter Assessment (IOA): Analysis of the auxiliary power unit

NASA Technical Reports Server (NTRS)

Barnes, J. E.

1986-01-01

The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. This report documents the independent analysis results corresponding to the Orbiter Auxiliary Power Unit (APU). The APUs are required to provide power to the Orbiter hydraulics systems during ascent and entry flight phases for aerosurface actuation, main engine gimballing, landing gear extension, and other vital functions. For analysis purposes, the APU system was broken down into ten functional subsystems. Each level of hardware was evaluated and analyzed for possible failure modes and effects. Criticality was assigned based upon the severity of the effect for each failure mode. A preponderance of 1/1 criticality items were related to failures that allowed the hydrazine fuel to escape into the Orbiter aft compartment, creating a severe fire hazard, and failures that caused loss of the gas generator injector cooling system.
Buddhism, the status of women and the spread of HIV/AIDS in Thailand.

PubMed

Klunklin, Areewan; Greenwood, Jennifer

2005-01-01

The common-sense construction of Buddhism is that of a general power for good; the less positive aspects of Buddhism's power, especially when reinforced by folklore and ancient superstition, is infrequently recognised. In this article we make explicit Buddhism's less positive power, particularly as it relates to the status of women and, by implication, its role in the human immunodeficiency (HIV)/acquired immune deficiency syndrome (AIDS) epidemic in Thailand. The Buddhist, folklore, and superstitious bases of Thai misogyny are explored, together with its expression in the differential gender roles of women and men. In addition, the attitudes of both women and men to commercial sex workers (CSWs) and condom use is discussed. The implications of these attitudinal analyses to the epidemiology of HIV/AIDS in Thailand is outlined. We argue that the current spread of HIV/AIDS in Thailand is primarily a function of the inferior status of women, which, in turn, is a function of Buddhism and Thai cultural beliefs. In light of this, some realistic strategies to address the problem also are discussed.
Sizing Dynamic Wireless Charging for Light-Duty Electric Vehicles in Roadway Applications

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

Foote, Andrew P; Ozpineci, Burak; Chinthavali, Madhu Sudhan

Dynamic wireless charging is a possible cure for the range limitations seen in electric vehicles (EVs) once implemented in highways or city streets. The contribution of this paper is the use of experimental data to show that the expected energy gain from a dynamic wireless power transfer (WPT) system is largely a function of average speed, which allows the power level and number of coils per mile of a dynamic WPT system to be sized for the sustained operation of an EV. First, data from dynamometer testing is used to determine the instantaneous energy requirements of a light-duty EV. Then,more » experimental data is applied to determine the theoretical energy gained by passing over a coil as a function of velocity and power level. Related simulations are performed to explore possible methods of placing WPT coils within roadways with comparisons to the constant velocity case. Analyses with these cases demonstrate what system ratings are needed to meet the energy requirements of the EV. The simulations are also used to determine onboard energy storage requirements for each driving cycle.« less
Quantitative relations between risk, return and firm size

NASA Astrophysics Data System (ADS)

Podobnik, B.; Horvatic, D.; Petersen, A. M.; Stanley, H. E.

2009-03-01

We analyze —for a large set of stocks comprising four financial indices— the annual logarithmic growth rate R and the firm size, quantified by the market capitalization MC. For the Nasdaq Composite and the New York Stock Exchange Composite we find that the probability density functions of growth rates are Laplace ones in the broad central region, where the standard deviation σ(R), as a measure of risk, decreases with the MC as a power law σ(R)~(MC)- β. For both the Nasdaq Composite and the S&P 500, we find that the average growth rate langRrang decreases faster than σ(R) with MC, implying that the return-to-risk ratio langRrang/σ(R) also decreases with MC. For the S&P 500, langRrang and langRrang/σ(R) also follow power laws. For a 20-year time horizon, for the Nasdaq Composite we find that σ(R) vs. MC exhibits a functional form called a volatility smile, while for the NYSE Composite, we find power law stability between σ(r) and MC.
Response of power systems to the San Fernando Valley earthquake of 9 February 1971. Final report

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

Schiff, A.J.; Yao, J.T.P.

1972-01-01

The impact of the San Fernando Valley earthquake on electric power systems is discussed. Particular attention focused on the following three areas; (1) the effects of an earthquake on the power network in the Western States, (2) the failure of subsystems and components of the power system, and (3) the loss of power to hospitals. The report includes sections on the description and functions of major components of a power network, existing procedures to protect the network, safety devices within the system which influence the network, a summary of the effects of the San Fernando Valley earthquake on the Westernmore » States Power Network, and present efforts to reduce the network vulnerability to faults. Also included in the report are a review of design procedures and practices prior to the San Fernando Valley earthquake and descriptions of types of damage to electrical equipment, dynamic analysis of equipment failures, equipment surviving the San Fernando Valley earthquake and new seismic design specifications. In addition, some observations and insights gained during the study, which are not directly related to power systems are discussed.« less
An overview of polymer ageing studies in the nuclear power industry

NASA Astrophysics Data System (ADS)

Burnay, S. G.

2001-12-01

Polymeric components are widely used in nuclear power plants (NPPs) in equipment which is important to the safety of the plant. The degradation of such components is therefore of considerable interest to the industry and its regulatory bodies, generating a large number of studies worldwide. Some of these components need to remain functional over the full operational life of the plant, which may span up to 60 years. Predictive modelling of their behaviour is therefore of key importance. This paper outlines the main areas of research, particularly relating to the use of elastomeric seals and polymeric cable insulation in NPP.
Power law behavior of RR-interval variability in healthy middle-aged persons, patients with recent acute myocardial infarction, and patients with heart transplants

NASA Technical Reports Server (NTRS)

Bigger, J. T. Jr; Steinman, R. C.; Rolnitzky, L. M.; Fleiss, J. L.; Albrecht, P.; Cohen, R. J.

1996-01-01

BACKGROUND. The purposes of the present study were (1) to establish normal values for the regression of log(power) on log(frequency) for, RR-interval fluctuations in healthy middle-aged persons, (2) to determine the effects of myocardial infarction on the regression of log(power) on log(frequency), (3) to determine the effect of cardiac denervation on the regression of log(power) on log(frequency), and (4) to assess the ability of power law regression parameters to predict death after myocardial infarction. METHODS AND RESULTS. We studied three groups: (1) 715 patients with recent myocardial infarction; (2) 274 healthy persons age and sex matched to the infarct sample; and (3) 19 patients with heart transplants. Twenty-four-hour RR-interval power spectra were computed using fast Fourier transforms and log(power) was regressed on log(frequency) between 10(-4) and 10(-2) Hz. There was a power law relation between log(power) and log(frequency). That is, the function described a descending straight line that had a slope of approximately -1 in healthy subjects. For the myocardial infarction group, the regression line for log(power) on log(frequency) was shifted downward and had a steeper negative slope (-1.15). The transplant (denervated) group showed a larger downward shift in the regression line and a much steeper negative slope (-2.08). The correlation between traditional power spectral bands and slope was weak, and that with log(power) at 10(-4) Hz was only moderate. Slope and log(power) at 10(-4) Hz were used to predict mortality and were compared with the predictive value of traditional power spectral bands. Slope and log(power) at 10(-4) Hz were excellent predictors of all-cause mortality or arrhythmic death. To optimize the prediction of death, we calculated a log(power) intercept that was uncorrelated with the slope of the power law regression line. We found that the combination of slope and zero-correlation log(power) was an outstanding predictor, with a relative risk of > 10, and was better than any combination of the traditional power spectral bands. The combination of slope and log(power) at 10(-4) Hz also was an excellent predictor of death after myocardial infarction. CONCLUSIONS. Myocardial infarction or denervation of the heart causes a steeper slope and decreased height of the power law regression relation between log(power) and log(frequency) of RR-interval fluctuations. Individually and, especially, combined, the power law regression parameters are excellent predictors of death of any cause or arrhythmic death and predict these outcomes better than the traditional power spectral bands.
3D printing of functional biomaterials for tissue engineering.

PubMed

Zhu, Wei; Ma, Xuanyi; Gou, Maling; Mei, Deqing; Zhang, Kang; Chen, Shaochen

2016-08-01

3D printing is emerging as a powerful tool for tissue engineering by enabling 3D cell culture within complex 3D biomimetic architectures. This review discusses the prevailing 3D printing techniques and their most recent applications in building tissue constructs. The work associated with relatively well-known inkjet and extrusion-based bioprinting is presented with the latest advances in the fields. Emphasis is put on introducing two relatively new light-assisted bioprinting techniques, including digital light processing (DLP)-based bioprinting and laser based two photon polymerization (TPP) bioprinting. 3D bioprinting of vasculature network is particularly discussed for its foremost significance in maintaining tissue viability and promoting functional maturation. Limitations to current bioprinting approaches, as well as future directions of bioprinting functional tissues are also discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.
High-voltage, high-power, solid-state remote power controllers for aerospace applications

NASA Technical Reports Server (NTRS)

Sturman, J. C.

1985-01-01

Two general types of remote power controller (RPC) that combine the functions of a circuit breaker and a switch were developed for use in direct-current (dc) aerospace systems. Power-switching devices used in these designs are the relatively new gate-turnoff thyristor (GTO) and poweer metal-oxide-semiconductor field-effect transistors (MOSFET). The various RPC's can switch dc voltages to 1200 V and currents to 100 A. Seven different units were constructed and subjected to comprehensive laboratory and thermal vacuum testing. Two of these were dual units that switch both positive and negative voltages simultaneously. The RPC's using MOSFET's have slow turnon and turnoff times to limit voltage spiking from high di/dt. The GTO's have much faster transition times. All RPC's have programmable overload tripout and microsecond tripout for large overloads. The basic circuits developed can be used to build switchgear limited only by the ratings of the switching device used.
Control of plasma stored energy for burn control using DIII-D in-vessel coils

DOE PAGES

Hawryluk, Richard J.; Eidietis, Nicholas W.; Grierson, Brian A.; ...

2015-04-09

A new approach has been experimentally demonstrated to control the stored energy by applying a non-axisymmetric magnetic field using the DIII-D in-vessel coils to modify the energy confinement time. In future burning plasma experiments as well as magnetic fusion energy power plants, various concepts have been proposed to control the fusion power. The fusion power in a power plant operating at high gain can be related to the plasma stored energy and hence, is a strong function of the energy confinement time. Thus, an actuator that modifies the confinement time can be used to adjust the fusion power. In relativelymore » low collisionality DIII-D discharges, the application of nonaxisymmetric magnetic fields results in a decrease in confinement time and density pumpout. Furthermore, gas puffing was used to compensate the density pumpout in the pedestal while control of the stored energy was demonstrated by the application of non-axisymmetric fields.« less
Make-up wells drilling cost in financial model for a geothermal project

NASA Astrophysics Data System (ADS)

Oktaviani Purwaningsih, Fitri; Husnie, Ruly; Afuar, Waldy; Abdurrahman, Gugun

2017-12-01

After commissioning of a power plant, geothermal reservoir will encounter pressure decline, which will affect wells productivity. Therefore, further drilling is carried out to enhance steam production. Make-up wells are production wells drilled inside an already confirmed reservoir to maintain steam production in a certain level. Based on Sanyal (2004), geothermal power cost consists of three components, those are capital cost, O&M cost and make-up drilling cost. The make-up drilling cost component is a major part of power cost which will give big influence in a whole economical value of the project. The objective of this paper it to analyse the make-up wells drilling cost component in financial model of a geothermal power project. The research will calculate make-up wells requirements, drilling costs as a function of time and how they influence the financial model and affect the power cost. The best scenario in determining make-up wells strategy in relation with the project financial model would be the result of this research.
High-temperature, high-power-density thermionic energy conversion for space

NASA Technical Reports Server (NTRS)

Morris, J. F.

1977-01-01

Theoretic converter outputs and efficiencies indicate the need to consider thermionic energy conversion (TEC) with greater power densities and higher temperatures within reasonable limits for space missions. Converter-output power density, voltage, and efficiency as functions of current density were determined for 1400-to-2000 K emitters with 725-to-1000 K collectors. The results encourage utilization of TEC with hotter-than-1650 K emitters and greater-than-6W sq cm outputs to attain better efficiencies, greater voltages, and higher waste-heat-rejection temperatures for multihundred-kilowatt space-power applications. For example, 1800 K, 30 A sq cm TEC operation for NEP compared with the 1650 K, 5 A/sq cm case should allow much lower radiation weights, substantially fewer and/or smaller emitter heat pipes, significantly reduced reactor and shield-related weights, many fewer converters and associated current-collecting bus bars, less power conditioning, and lower transmission losses. Integration of these effects should yield considerably reduced NEP specific weights.
Contribution for Iron Vapor and Radiation Distribution Affected by Current Frequency of Pulsed Arc

NASA Astrophysics Data System (ADS)

Shimokura, Takuya; Mori, Yusuke; Iwao, Toru; Yumoto, Motoshige

Pulsed GTA welding has been used for improvement of stability, weld speed, and heat input control. However, the temperature and radiation power of the pulsed arc have not been elucidated. Furthermore, arc contamination by metal vapor changes the arc characteristics, e.g. by increasing radiation power. In this case, the metal vapor in pulsed GTA welding changes the distribution of temperature and radiation power as a function of time. This paper presents the relation between metal vapor and radiation power at different pulse frequencies. We calculate the Fe vapor distribution of the pulsed current. Results show that the Fe vapor is transported at fast arc velocity during the peak current period. During the base current period, the Fe vapor concentration is low and distribution is diffuse. The transition of Fe vapor distribution does not follow the pulsed current; the radiation power density distribution differs for high frequencies and low frequencies. In addition, the Fe vapor and radiation distribution are affected by the pulsed arc current frequency.
Primary and secondary electrical space power based on advanced PEM systems

NASA Technical Reports Server (NTRS)

Vanderborgh, N. E.; Hedstrom, J. C.; Stroh, K. R.; Huff, J. R.

1993-01-01

For new space ventures, power continues to be a pacing function for mission planning and experiment endurance. Although electrochemical power is a well demonstrated space power technology, current hardware limitations impact future mission viability. In order to document and augment electrochemical technology, a series of experiments for the National Aeronautics and Space Administration Lewis Research Center (NASA LeRC) are underway at the Los Alamos National Laboratory that define operational parameters on contemporary proton exchange membrane (PEM) hardware operating with hydrogen and oxygen reactants. Because of the high efficiency possible for water electrolysis, this hardware is also thought part of a secondary battery design built around stored reactants - the so-called regenerative fuel cell. An overview of stack testing at Los Alamos and of analyses related to regenerative fuel cell systems are provided in this paper. Finally, this paper describes work looking at innovative concepts that remove complexity from stack hardware with the specific intent of higher system reliability. This new concept offers the potential for unprecedented electrochemical power system energy densities.
Relationship between delta power and the electrocardiogram-derived cardiopulmonary spectrogram: possible implications for assessing the effectiveness of sleep.

PubMed

Thomas, Robert Joseph; Mietus, Joseph E; Peng, Chung-Kang; Guo, Dan; Gozal, David; Montgomery-Downs, Hawley; Gottlieb, Daniel J; Wang, Cheng-Yen; Goldberger, Ary L

2014-01-01

The physiologic relationship between slow-wave activity (SWA) (0-4 Hz) on the electroencephalogram (EEG) and high-frequency (0.1-0.4 Hz) cardiopulmonary coupling (CPC) derived from electrocardiogram (ECG) sleep spectrograms is not known. Because high-frequency CPC appears to be a biomarker of stable sleep, we tested the hypothesis that that slow-wave EEG power would show a relatively fixed-time relationship to periods of high-frequency CPC. Furthermore, we speculated that this correlation would be independent of conventional nonrapid eye movement (NREM) sleep stages. We analyzed selected datasets from an archived polysomnography (PSG) database, the Sleep Heart Health Study I (SHHS-I). We employed the cross-correlation technique to measure the degree of which 2 signals are correlated as a function of a time lag between them. Correlation analyses between high-frequency CPC and delta power (computed both as absolute and normalized values) from 3150 subjects with an apnea-hypopnea index (AHI) of ≤5 events per hour of sleep were performed. The overall correlation (r) between delta power and high-frequency coupling (HFC) power was 0.40±0.18 (P=.001). Normalized delta power provided improved correlation relative to absolute delta power. Correlations were somewhat reduced in the second half relative to the first half of the night (r=0.45±0.20 vs r=0.34±0.23). Correlations were only affected by age in the eighth decade. There were no sex differences and only small racial or ethnic differences were noted. These results support a tight temporal relationship between slow wave power, both within and outside conventional slow wave sleep periods, and high frequency cardiopulmonary coupling, an ECG-derived biomarker of "stable" sleep. These findings raise mechanistic questions regarding the cross-system integration of neural and cardiopulmonary control during sleep. Copyright © 2013 Elsevier B.V. All rights reserved.
Microwave enhanced recovery of nickel-copper ore: communition and floatability aspects.

PubMed

Henda, R; Hermas, A; Gedye, R; Islam, M R

2005-01-01

A study describing the effect of microwave radiation, at a frequency of 2450 MHz, on the processes of communication and flotation of a complex sulphide nickel-copper ore is presented. Ore communication has been investigated under standard radiation-free conditions and after ore treatment in a radiated environment as a function of ore size, exposure time to radiation, and microwave power. The findings show that communication is tremendously improved by microwave radiation with values of the relative work index as low as 23% at a microwave power of 1.406 kW and after 10 s of exposure time. Communication is affected by exposure time and microwave power in a nontrivial manner. In terms of ore floatability, the experimental tests have been carried out on a sample of 75 microm in size under different exposure times. The results show that both ore concentrate recoveries and grades of nickel and copper are significantly enhanced after microwave treatment of the ore with relative increases in recovered concentrate, grade of nickel, and grade of copper of 26 wt%, 15 wt%, and 27%, respectively, at a microwave power of 1330 kW and after 30 s of exposure time.
Effortless Attention as a Biomarker for Experienced Mindfulness Practitioners.

PubMed

Tanaka, Guaraci Ken; Maslahati, Tolou; Gongora, Mariana; Bittencourt, Juliana; Lopez, Luiz Carlos Serramo; Demarzo, Marcelo Marcos Piva; Budde, Henning; Teixeira, Silmar; Basile, Luis Fernando; Campayo, Javier Garcia; Cagy, Mauricio; Ribeiro, Pedro; Velasques, Bruna

2015-01-01

The present study aimed at comparing frontal beta power between long-term (LTM) and first-time meditators (FTM), before, during and after a meditation session. We hypothesized that LTM would present lower beta power than FTM due to lower effort of attention and awareness. Twenty one participants were recruited, eleven of whom were long-term meditators. The subjects were asked to rest for 4 minutes before and after open monitoring (OM) meditation (40 minutes). The two-way ANOVA revealed an interaction between the group and moment factors for the Fp1 (p<0.01), F7 (p = 0.01), F3 (p<0.01), Fz (p<0.01), F4 (p<0.01), F8 (p<0.01) electrodes. We found low power frontal beta activity for LTM during the task and this may be associated with the fact that OM is related to bottom-up pathways that are not present in FTM. We hypothesized that the frontal beta power pattern may be a biomarker for LTM. It may also be related to improving an attentive state and to the efficiency of cognitive functions, as well as to the long-term experience with meditation (i.e., life-time experience and frequency of practice).
Effects of a Supervised versus an Unsupervised Combined Balance and Strength Training Program on Balance and Muscle Power in Healthy Older Adults: A Randomized Controlled Trial.

PubMed

Lacroix, André; Kressig, Reto W; Muehlbauer, Thomas; Gschwind, Yves J; Pfenninger, Barbara; Bruegger, Othmar; Granacher, Urs

2016-01-01

Losses in lower extremity muscle strength/power, muscle mass and deficits in static and particularly dynamic balance due to aging are associated with impaired functional performance and an increased fall risk. It has been shown that the combination of balance and strength training (BST) mitigates these age-related deficits. However, it is unresolved whether supervised versus unsupervised BST is equally effective in improving muscle power and balance in older adults. This study examined the impact of a 12-week BST program followed by 12 weeks of detraining on measures of balance and muscle power in healthy older adults enrolled in supervised (SUP) or unsupervised (UNSUP) training. Sixty-six older adults (men: 25, women: 41; age 73 ± 4 years) were randomly assigned to a SUP group (2/week supervised training, 1/week unsupervised training; n = 22), an UNSUP group (3/week unsupervised training; n = 22) or a passive control group (CON; n = 22). Static (i.e., Romberg Test) and dynamic (i.e., 10-meter walk test) steady-state, proactive (i.e., Timed Up and Go Test, Functional Reach Test), and reactive balance (e.g., Push and Release Test), as well as lower extremity muscle power (i.e., Chair Stand Test; Stair Ascent and Descent Test) were tested before and after the active training phase as well as after detraining. Adherence rates to training were 92% for SUP and 97% for UNSUP. BST resulted in significant group × time interactions. Post hoc analyses showed, among others, significant training-related improvements for the Romberg Test, stride velocity, Timed Up and Go Test, and Chair Stand Test in favor of the SUP group. Following detraining, significantly enhanced performances (compared to baseline) were still present in 13 variables for the SUP group and in 10 variables for the UNSUP group. Twelve weeks of BST proved to be safe (no training-related injuries) and feasible (high attendance rates of >90%). Deficits of balance and lower extremity muscle power can be mitigated by BST in healthy older adults. Additionally, supervised as compared to unsupervised BST was more effective. Thus, it is recommended to counteract intrinsic fall risk factors by applying supervised BST programs for older adults. © 2015 The Author(s) Published by S. Karger AG, Basel.

Galaxy power spectrum in redshift space: Combining perturbation theory with the halo model

NASA Astrophysics Data System (ADS)

Okumura, Teppei; Hand, Nick; Seljak, Uroš; Vlah, Zvonimir; Desjacques, Vincent

2015-11-01

Theoretical modeling of the redshift-space power spectrum of galaxies is crucially important to correctly extract cosmological information from galaxy redshift surveys. The task is complicated by the nonlinear biasing and redshift space distortion (RSD) effects, which change with halo mass, and by the wide distribution of halo masses and their occupations by galaxies. One of the main modeling challenges is the existence of satellite galaxies that have both radial distribution inside the halos and large virial velocities inside halos, a phenomenon known as the Finger-of-God (FoG) effect. We present a model for the redshift-space power spectrum of galaxies in which we decompose a given galaxy sample into central and satellite galaxies and relate different contributions to the power spectrum to 1-halo and 2-halo terms in a halo model. Our primary goal is to ensure that any parameters that we introduce have physically meaningful values, and are not just fitting parameters. For the lowest order 2-halo terms we use the previously developed RSD modeling of halos in the context of distribution function and perturbation theory approach. This term needs to be multiplied by the effect of radial distances and velocities of satellites inside the halo. To this one needs to add the 1-halo terms, which are nonperturbative. We show that the real space 1-halo terms can be modeled as almost constant, with the finite extent of the satellites inside the halo inducing a small k2R2 term over the range of scales of interest, where R is related to the size of the halo given by its halo mass. We adopt a similar model for FoG in redshift space, ensuring that FoG velocity dispersion is related to the halo mass. For FoG k2 type expansions do not work over the range of scales of interest and FoG resummation must be used instead. We test several simple damping functions to model the velocity dispersion FoG effect. Applying the formalism to mock galaxies modeled after the "CMASS" sample of the BOSS survey, we find that our predictions for the redshift-space power spectra are accurate up to k ≃0.4 h Mpc-1 within 1% if the halo power spectrum is measured using N -body simulations and within 3% if it is modeled using perturbation theory.
Cardiovascular autonomic function in Cushing's syndrome.

PubMed

Fallo, F; Maffei, P; Dalla Pozza, A; Carli, M; Della Mea, P; Lupia, M; Rabbia, F; Sonino, N

2009-01-01

Cardiac autonomic dysfunction is associated with increased cardiovascular mortality. No data on sympathovagal balance are available in patients with Cushing's syndrome, in whom cardiovascular risk is high. We studied 10 patients with newly diagnosed Cushing's syndrome (1 male/9 females; age mean+/-SD, 47+/-10 yr) and 10 control subjects matched for age, sex, body mass index, and cardiovascular risk factors. In both groups there were 7 patients with arterial hypertension, 3 with diabetes mellitus, and 2 with obesity. Cardiac autonomic function was evaluated by analysis of short time heart rate variability (HRV) measures in frequency domain over 24-h, daytime, and nighttime. The 24-h ambulatory blood pressure monitoring and echocardiography were also performed. In comparison with controls, patients with Cushing's syndrome had lower 24-h (1.3+/-0.6 vs 3.7+/-1.5, mean+/-SD, p<0.01), daytime (2.0+/-1.4 vs 4.5+/-1.6, p<0.01), and night-time (1.0+/-0.4 vs 3.5+/-2.3, p<0.01) low-frequency/ high frequency (LF/HF) power ratio. In the presence of similar LF power, the difference was due to elevation in HF power in Cushing's syndrome compared to controls: 24-h, 12.7+/-6.7 vs 5.8+/-2.8, p<0.01; daytime, 10.2+/-7.3 vs 4.5+/-2.1, p<0.05; nighttime, 14.2+/-7.0 vs 7.8+/-4.7, p<0.05. Eight Cushing patients vs 4 controls had a non-dipping blood pressure profile. At echocardiography, Cushing patients had a greater left ventricular mass index and/or relative wall thickness, and impaired diastolic function, compared with controls. Compared to controls, patients with Cushing's syndrome showed a sympathovagal imbalance, characterized by a relatively increased parasympathetic activity. Whether this autonomic alteration is meant to counterbalance cortisol-induced effects on blood pressure and cardiac structure/function or has a different pathophysiological significance is still unknown.
Formation of massive, dense cores by cloud-cloud collisions

NASA Astrophysics Data System (ADS)

Takahira, Ken; Shima, Kazuhiro; Habe, Asao; Tasker, Elizabeth J.

2018-03-01

We performed sub-parsec (˜ 0.014 pc) scale simulations of cloud-cloud collisions of two idealized turbulent molecular clouds (MCs) with different masses in the range of (0.76-2.67) × 104 M_{⊙} and with collision speeds of 5-30 km s-1. Those parameters are larger than in Takahira, Tasker, and Habe (2014, ApJ, 792, 63), in which study the colliding system showed a partial gaseous arc morphology that supports the NANTEN observations of objects indicated to be colliding MCs using numerical simulations. Gas clumps with density greater than 10-20 g cm-3 were identified as pre-stellar cores and tracked through the simulation to investigate the effects of the mass of colliding clouds and the collision speeds on the resulting core population. Our results demonstrate that the smaller cloud property is more important for the results of cloud-cloud collisions. The mass function of formed cores can be approximated by a power-law relation with an index γ = -1.6 in slower cloud-cloud collisions (v ˜ 5 km s-1), and is in good agreement with observation of MCs. A faster relative speed increases the number of cores formed in the early stage of collisions and shortens the gas accretion phase of cores in the shocked region, leading to the suppression of core growth. The bending point appears in the high-mass part of the core mass function and the bending point mass decreases with increase in collision speed for the same combination of colliding clouds. The higher-mass part of the core mass function than the bending point mass can be approximated by a power law with γ = -2-3 that is similar to the power index of the massive part of the observed stellar initial mass function. We discuss implications of our results for the massive-star formation in our Galaxy.
Formation of massive, dense cores by cloud-cloud collisions

NASA Astrophysics Data System (ADS)

Takahira, Ken; Shima, Kazuhiro; Habe, Asao; Tasker, Elizabeth J.

2018-05-01

We performed sub-parsec (˜ 0.014 pc) scale simulations of cloud-cloud collisions of two idealized turbulent molecular clouds (MCs) with different masses in the range of (0.76-2.67) × 104 M_{⊙} and with collision speeds of 5-30 km s-1. Those parameters are larger than in Takahira, Tasker, and Habe (2014, ApJ, 792, 63), in which study the colliding system showed a partial gaseous arc morphology that supports the NANTEN observations of objects indicated to be colliding MCs using numerical simulations. Gas clumps with density greater than 10-20 g cm-3 were identified as pre-stellar cores and tracked through the simulation to investigate the effects of the mass of colliding clouds and the collision speeds on the resulting core population. Our results demonstrate that the smaller cloud property is more important for the results of cloud-cloud collisions. The mass function of formed cores can be approximated by a power-law relation with an index γ = -1.6 in slower cloud-cloud collisions (v ˜ 5 km s-1), and is in good agreement with observation of MCs. A faster relative speed increases the number of cores formed in the early stage of collisions and shortens the gas accretion phase of cores in the shocked region, leading to the suppression of core growth. The bending point appears in the high-mass part of the core mass function and the bending point mass decreases with increase in collision speed for the same combination of colliding clouds. The higher-mass part of the core mass function than the bending point mass can be approximated by a power law with γ = -2-3 that is similar to the power index of the massive part of the observed stellar initial mass function. We discuss implications of our results for the massive-star formation in our Galaxy.
Beta Function Quintessence Cosmological Parameters and Fundamental Constants I: Power and Inverse Power Law Dark Energy Potentials

NASA Astrophysics Data System (ADS)

Thompson, Rodger I.

2018-04-01

This investigation explores using the beta function formalism to calculate analytic solutions for the observable parameters in rolling scalar field cosmologies. The beta function in this case is the derivative of the scalar ϕ with respect to the natural log of the scale factor a, β (φ )=d φ /d ln (a). Once the beta function is specified, modulo a boundary condition, the evolution of the scalar ϕ as a function of the scale factor is completely determined. A rolling scalar field cosmology is defined by its action which can contain a range of physically motivated dark energy potentials. The beta function is chosen so that the associated "beta potential" is an accurate, but not exact, representation of the appropriate dark energy model potential. The basic concept is that the action with the beta potential is so similar to the action with the model potential that solutions using the beta action are accurate representations of solutions using the model action. The beta function provides an extra equation to calculate analytic functions of the cosmologies parameters as a function of the scale factor that are that are not calculable using only the model action. As an example this investigation uses a quintessence cosmology to demonstrate the method for power and inverse power law dark energy potentials. An interesting result of the investigation is that the Hubble parameter H is almost completely insensitive to the power of the potentials and that ΛCDM is part of the family of quintessence cosmology power law potentials with a power of zero.
Beta function quintessence cosmological parameters and fundamental constants - I. Power and inverse power law dark energy potentials

NASA Astrophysics Data System (ADS)

Thompson, Rodger I.

2018-07-01

This investigation explores using the beta function formalism to calculate analytic solutions for the observable parameters in rolling scalar field cosmologies. The beta function in this case is the derivative of the scalar φ with respect to the natural log of the scale factor a, β (φ)=d φ/d ln (a). Once the beta function is specified, modulo a boundary condition, the evolution of the scalar φ as a function of the scale factor is completely determined. A rolling scalar field cosmology is defined by its action which can contain a range of physically motivated dark energy potentials. The beta function is chosen so that the associated `beta potential' is an accurate, but not exact, representation of the appropriate dark energy model potential. The basic concept is that the action with the beta potential is so similar to the action with the model potential that solutions using the beta action are accurate representations of solutions using the model action. The beta function provides an extra equation to calculate analytic functions of the cosmologies parameters as a function of the scale factor that are not calculable using only the model action. As an example, this investigation uses a quintessence cosmology to demonstrate the method for power and inverse power law dark energy potentials. An interesting result of the investigation is that the Hubble parameter H is almost completely insensitive to the power of the potentials and that Λ cold dark matter is part of the family of quintessence cosmology power-law potentials with a power of zero.
Comparisons of self-ratings on managerial competencies, research capability, time management, executive power, workload and work stress among nurse administrators.

PubMed

Kang, Chun-Mei; Chiu, Hsiao-Ting; Hu, Yi-Chun; Chen, Hsiao-Lien; Lee, Pi-Hsia; Chang, Wen-Yin

2012-10-01

To assess the level of and the differences in managerial competencies, research capability, time management, executive power, workload and work-stress ratings among nurse administrators (NAs), and to determine the best predictors of managerial competencies for NAs. Although NAs require multifaceted managerial competencies, research related to NAs' managerial competencies is limited. A cross-sectional survey was conducted with 330 NAs from 16 acute care hospitals. Managerial competencies were determined through a self-developed questionnaire. Data were collected in 2011. All NAs gave themselves the highest rating on integrity and the lowest on both financial/budgeting and business acumen. All scores for managerial competencies, research capability, time management and executive power showed a statistically significant correlation. The stepwise regression analysis revealed that age; having received NA training; having completed a nursing project independently; and scores for research capability, executive power and workload could explain 63.2% of the total variance in managerial competencies. The present study provides recommendations for future administrative training programmes to increase NAs' managerial competency in fulfilling their management roles and functions. The findings inform leaders of hospitals where NAs need to develop additional competencies concerning the type of training NAs need to function proficiently. © 2012 Blackwell Publishing Ltd.
Middle-ear velocity transfer function, cochlear input immittance, and middle-ear efficiency in chinchilla.

PubMed

Ravicz, Michael E; Rosowski, John J

2013-10-01

The transfer function H(V) between stapes velocity V(S) and sound pressure near the tympanic membrane P(TM) is a descriptor of sound transmission through the middle ear (ME). The ME power transmission efficiency (MEE), the ratio of sound power entering the cochlea to power entering the middle ear, was computed from H(V) measured in seven chinchilla ears and previously reported measurements of ME input admittance Y(TM) and ME pressure gain G(MEP) [Ravicz and Rosowski, J. Acoust. Soc. Am. 132, 2437-2454 (2012); J. Acoust. Soc. Am. 133, 2208-2223 (2013)] in the same ears. The ME was open, and a pressure sensor was inserted into the cochlear vestibule for most measurements. The cochlear input admittance Y(C) computed from H(V) and G(MEP) is controlled by a combination of mass and resistance and is consistent with a minimum-phase system up to 27 kHz. The real part Re{Y(C)}, which relates cochlear sound power to inner-ear sound pressure, decreased gradually with frequency up to 25 kHz and more rapidly above that. MEE was about 0.5 between 0.1 and 8 kHz, higher than previous estimates in this species, and decreased sharply at higher frequencies.
Middle-ear velocity transfer function, cochlear input immittance, and middle-ear efficiency in chinchilla

PubMed Central

Ravicz, Michael E.; Rosowski, John J.

2013-01-01

The transfer function HV between stapes velocity VS and sound pressure near the tympanic membrane PTM is a descriptor of sound transmission through the middle ear (ME). The ME power transmission efficiency (MEE), the ratio of sound power entering the cochlea to power entering the middle ear, was computed from HV measured in seven chinchilla ears and previously reported measurements of ME input admittance YTM and ME pressure gain GMEP [Ravicz and Rosowski, J. Acoust. Soc. Am. 132, 2437–2454 (2012); J. Acoust. Soc. Am. 133, 2208–2223 (2013)] in the same ears. The ME was open, and a pressure sensor was inserted into the cochlear vestibule for most measurements. The cochlear input admittance YC computed from HV and GMEP is controlled by a combination of mass and resistance and is consistent with a minimum-phase system up to 27 kHz. The real part Re{YC}, which relates cochlear sound power to inner-ear sound pressure, decreased gradually with frequency up to 25 kHz and more rapidly above that. MEE was about 0.5 between 0.1 and 8 kHz, higher than previous estimates in this species, and decreased sharply at higher frequencies. PMID:24116422
Measurement Properties of the Smartphone-Based B-B Score in Current Shoulder Pathologies

PubMed Central

Pichonnaz, Claude; Duc, Cyntia; Gleeson, Nigel; Ancey, Céline; Jaccard, Hervé; Lécureux, Estelle; Farron, Alain; Jolles, Brigitte M.; Aminian, Kamiar

2015-01-01

This study is aimed at the determination of the measurement properties of the shoulder function B-B Score measured with a smartphone. This score measures the symmetry between sides of a power-related metric for two selected movements, with 100% representing perfect symmetry. Twenty healthy participants, 20 patients with rotator cuff conditions, 23 with fractures, 22 with capsulitis, and 23 with shoulder instabilities were measured twice across a six-month interval using the B-B Score and shoulder function questionnaires. The discriminative power, responsiveness, diagnostic power, concurrent validity, minimal detectable change (MDC), minimal clinically important improvement (MCII), and patient acceptable symptom state (PASS) were evaluated. Significant differences with the control group and significant baseline—six-month differences were found for the rotator cuff condition, fracture, and capsulitis patient groups. The B-B Score was responsive and demonstrated excellent diagnostic power, except for shoulder instability. The correlations with clinical scores were generally moderate to high, but lower for instability. The MDC was 18.1%, the MCII was 25.2%, and the PASS was 77.6. No floor effect was observed. The B-B Score demonstrated excellent measurement properties in populations with rotator cuff conditions, proximal humerus fractures, and capsulitis, and can thus be used as a routine test to evaluate those patients. PMID:26506355
Interaction, Power, and the Institution: Uncovering the Negotiations That Organize the Planning Work of Social Studies Teachers

ERIC Educational Resources Information Center

Lisanti, Melissa Wall

2015-01-01

With the proliferation of standards and accountability systems in education, questions about how they function and intersect with broader patterns of institutional relations await investigation. The existing literature in social studies education is replete with studies that frame teachers' expertise for managing how instruction unfolds in the…
Educating in an Era of Orwellian Spin: Critical Media Literacy in the Classroom

ERIC Educational Resources Information Center

Orlowski, Paul

2006-01-01

Canadians live in a world of mega-spin where public relations corporate lobbyists play an increasingly larger role in news-making. To resist this trend, I have studied political ideology to understand the relationship between corporate media and systems of social, economic, and political power, and their hegemonic function, and indicate the bias…
The Division of Household Labor: Longitudinal Changes and Within-Couple Variation

ERIC Educational Resources Information Center

Lam, Chun Bun; McHale, Susan M.; Crouter, Ann C.

2012-01-01

This study examined how the division of household labor changed as a function of marital duration and whether within-couple variation in spouses' relative power and availability were linked to within-couple variation in the division of labor. On 4 occasions over 7 years, 188 stably married couples reported on their housework activities using daily…
An investigation of the relationship between physical fitness, self-concept, and sexual functioning.

PubMed

Jiannine, Lia M

2018-01-01

Obesity and inactivity have led to an increasing number of individuals with sexual dysfunctions (43% of women; 31% of men). Small bouts of exercise can drastically improve sexual functioning. Thus, the present study is designed to examine the effects of physical fitness and self-concept on sexual functioning. Fitness assessments and questionnaires were administered to 133 participants between the ages of 18 and 50 years. Physical fitness was assessed through body composition, cardiovascular endurance, muscular strength, and muscular endurance. Self-concept was presented as a total self-concept score and as six individual concepts of self. Sexual function was presented as both an aggregate score and five separate constructs of sexual functioning - fantasy/cognition, arousal, orgasm, behavior/experience, and drive/desire. The results indicated that sexual behavior/experience was predicted by body fat percentage. In men, fantasy was related to total self-concept; sexual behavior/experience was related to likeability. In women, arousal was predicted by cardiovascular endurance. Total self-concept was related to both orgasm and sex drive/desire. Power and muscular strength were significantly related to number of sexual partners in women but not men. The present study adds to the growing body of evidence indicating a positive relationship between physical fitness and sexual health. Individuals with sexual dysfunctions, particularly women, who are not persuaded by the currently publicized benefits of physical activity, may be inclined to exercise to improve sexual functioning.
The ACS Survey of Galactic Globular Clusters. VIII. Effects of Environment on Globular Cluster Global Mass Functions

NASA Astrophysics Data System (ADS)

Paust, Nathaniel E. Q.; Reid, I. Neill; Piotto, Giampaolo; Aparicio, Antonio; Anderson, Jay; Sarajedini, Ata; Bedin, Luigi R.; Chaboyer, Brian; Dotter, Aaron; Hempel, Maren; Majewski, Steven; Marín-Franch, A.; Milone, Antonino; Rosenberg, Alfred; Siegel, Michael

2010-02-01

We have used observations obtained as part of the Hubble Space Telescope/ACS Survey of Galactic Globular Clusters to construct global present-day mass functions for 17 globular clusters utilizing multi-mass King models to extrapolate from our observations to the global cluster behavior. The global present-day mass functions for these clusters are well matched by power laws from the turnoff, ≈0.8 M sun, to 0.2-0.3 M sun on the lower main sequence. The slopes of those power-law fits, α, have been correlated with an extensive set of intrinsic and extrinsic cluster properties to investigate which parameters may influence the form of the present-day mass function. We do not confirm previous suggestions of correlations between α and either metallicity or Galactic location. However, we do find a strong statistical correlation with the related parameters central surface brightness, μ V , and inferred central density, ρ0. The correlation is such that clusters with denser cores (stronger binding energy) tend to have steeper mass functions (a higher proportion of low-mass stars), suggesting that dynamical evolution due to external interactions may have played a key role in determining α. Thus, the present-day mass function may owe more to nurture than to nature. Detailed modeling of external dynamical effects is therefore a requisite for determining the initial mass function for Galactic globular clusters.
A best practice fall prevention exercise program to improve balance, strength / power, and psychosocial health in older adults: study protocol for a randomized controlled trial.

PubMed

Gschwind, Yves J; Kressig, Reto W; Lacroix, Andre; Muehlbauer, Thomas; Pfenninger, Barbara; Granacher, Urs

2013-10-09

With increasing age neuromuscular deficits (e.g., sarcopenia) may result in impaired physical performance and an increased risk for falls. Prominent intrinsic fall-risk factors are age-related decreases in balance and strength / power performance as well as cognitive decline. Additional studies are needed to develop specifically tailored exercise programs for older adults that can easily be implemented into clinical practice. Thus, the objective of the present trial is to assess the effects of a fall prevention program that was developed by an interdisciplinary expert panel on measures of balance, strength / power, body composition, cognition, psychosocial well-being, and falls self-efficacy in healthy older adults. Additionally, the time-related effects of detraining are tested. Healthy old people (n = 54) between the age of 65 to 80 years will participate in this trial. The testing protocol comprises tests for the assessment of static / dynamic steady-state balance (i.e., Sharpened Romberg Test, instrumented gait analysis), proactive balance (i.e., Functional Reach Test; Timed Up and Go Test), reactive balance (i.e., perturbation test during bipedal stance; Push and Release Test), strength (i.e., hand grip strength test; Chair Stand Test), and power (i.e., Stair Climb Power Test; countermovement jump). Further, body composition will be analysed using a bioelectrical impedance analysis system. In addition, questionnaires for the assessment of psychosocial (i.e., World Health Organisation Quality of Life Assessment-Bref), cognitive (i.e., Mini Mental State Examination), and fall risk determinants (i.e., Fall Efficacy Scale - International) will be included in the study protocol. Participants will be randomized into two intervention groups or the control / waiting group. After baseline measures, participants in the intervention groups will conduct a 12-week balance and strength / power exercise intervention 3 times per week, with each training session lasting 30 min. (actual training time). One intervention group will complete an extensive supervised training program, while the other intervention group will complete a short version ('3 times 3') that is home-based and controlled by weekly phone calls. Post-tests will be conducted right after the intervention period. Additionally, detraining effects will be measured 12 weeks after program cessation. The control group / waiting group will not participate in any specific intervention during the experimental period, but will receive the extensive supervised program after the experimental period. It is expected that particularly the supervised combination of balance and strength / power training will improve performance in variables of balance, strength / power, body composition, cognitive function, psychosocial well-being, and falls self-efficacy of older adults. In addition, information regarding fall risk assessment, dose-response-relations, detraining effects, and supervision of training will be provided. Further, training-induced health-relevant changes, such as improved performance in activities of daily living, cognitive function, and quality of life, as well as a reduced risk for falls may help to lower costs in the health care system. Finally, practitioners, therapists, and instructors will be provided with a scientifically evaluated feasible, safe, and easy-to-administer exercise program for fall prevention.
The relationship between perceived discomfort of static posture holding and posture holding time.

PubMed

Ogutu, Jack; Park, Woojin

2015-01-01

Few studies have investigated mathematical characteristics of the discomfort-time relationship during prolonged static posture holding (SPH) on an individual basis. Consequently, the discomfort-time relationship is not clearly understood at individual trial level. The objective of this study was to examine discomfort-time sequence data obtained from a large number of maximum-duration SPH trials to understand the perceived discomfort-posture holding time relationship at the individual SPH trial level. Thirty subjects (15 male, 15 female) participated in this study as paid volunteers. The subjects performed maximum-duration SPH trials employing 12 different wholebody static postures. The hand-held load for all the task trials was a ``generic'' box weighing 2 kg. Three mathematical functions, that is, linear, logarithmic and power functions were examined as possible mathematical models for representing individual discomfort-time profiles of SPH trials. Three different time increase patterns (negatively accelerated, linear and positively accelerated) were observed in the discomfort-time sequences data. The power function model with an additive constant term was found to adequately fit most (96.4%) of the observed discomfort-time sequences, and thus, was recommended as a general mathematical representation of the perceived discomfort-posture holding time relationship in SPH. The new knowledge on the nature of the discomfort-time relationship in SPH and the power function representation found in this study will facilitate analyzing discomfort-time data of SPH and developing future posture analysis tools for work-related discomfort control.
Skeletal muscle power and fatigue at the tolerable limit of ramp-incremental exercise in COPD.

PubMed

Cannon, Daniel T; Coelho, Ana Claudia; Cao, Robert; Cheng, Andrew; Porszasz, Janos; Casaburi, Richard; Rossiter, Harry B

2016-12-01

Muscle fatigue (a reduced power for a given activation) is common following exercise in chronic obstructive pulmonary disease (COPD). Whether muscle fatigue, and reduced maximal voluntary locomotor power, are sufficient to limit whole body exercise in COPD is unknown. We hypothesized in COPD: 1) exercise is terminated with a locomotor muscle power reserve; 2) reduction in maximal locomotor power is related to ventilatory limitation; and 3) muscle fatigue at intolerance is less than age-matched controls. We used a rapid switch from hyperbolic to isokinetic cycling to measure the decline in peak isokinetic power at the limit of incremental exercise ("performance fatigue") in 13 COPD patients (FEV 1 49 ± 17%pred) and 12 controls. By establishing the baseline relationship between muscle activity and isokinetic power, we apportioned performance fatigue into the reduction in muscle activation and muscle fatigue. Peak isokinetic power at intolerance was ~130% of peak incremental power in controls (274 ± 73 vs. 212 ± 84 W, P < 0.05), but ~260% in COPD patients (187 ± 141 vs. 72 ± 34 W, P < 0.05), greater than controls (P < 0.05). Muscle fatigue as a fraction of baseline peak isokinetic power was not different in COPD patients vs. controls (0.11 ± 0.20 vs. 0.19 ± 0.11). Baseline to intolerance, the median frequency of maximal isokinetic muscle activity, was unchanged in COPD patients but reduced in controls (+4.3 ± 11.6 vs. -5.5 ± 7.6%, P < 0.05). Performance fatigue as a fraction of peak incremental power was greater in COPD vs. controls and related to resting (FEV 1 /FVC) and peak exercise (V̇ E /maximal voluntary ventilation) pulmonary function (r 2 = 0.47 and 0.55, P < 0.05). COPD patients are more fatigable than controls, but this fatigue is insufficient to constrain locomotor power and define exercise intolerance. Copyright © 2016 the American Physiological Society.
Testing the linearity and independence assumptions of the generalized matching law for reinforcer magnitude: a residual meta-analysis.

PubMed

Cording, Jacinta R; McLean, Anthony P; Grace, Randolph C

2011-05-01

We conducted a residual meta-analysis to test the assumptions of the generalized matching law that effects of relative reinforcer magnitude on response allocation in concurrent schedules can be described by a power function and are independent from the effects of relative reinforcer rate. We identified five studies which varied magnitude ratios over at least four levels and six studies in which reinforcer rate and magnitude ratios were varied factorially. The generalized matching law provided a reasonably good description of the data, accounting for 77.1% and 90.1% of the variance in the two sets of studies. Results of polynomial regressions showed that there were no systematic patterns in pooled residuals as a function of predicted log response ratios for data sets in which relative magnitude was varied. For data sets in which relative rate and magnitude were varied factorially, there was a significant negative cubic pattern in the pooled residuals, suggesting that obtained response allocation was less extreme than predicted for conditions with extreme predicted values. However, subsequent analyses showed that this result was associated with results from conditions in one study in which the product of the rate and magnitude ratios was 63:1, and in which response allocation may have been attenuated by a ceiling effect. When data from these conditions were omitted, there were no significant components in the residuals. Although the number of available studies was small, results provide tentative support for the assumptions of the generalized matching law that effects of reinforcer magnitude ratios on choice can be described by a power function and are independent from reinforcer rate ratios. Copyright © 2011 Elsevier B.V. All rights reserved.
The complex contribution of sociodemographics to decision-making power in gay male couples

PubMed Central

Perry, Nicholas S.; Huebner, David M.; Baucom, Brian R. W.; Hoff, Colleen C.

2016-01-01

Relationship power is an important dyadic construct in close relationships that is associated with relationship health and partner’s individual health. Understanding what predicts power in heterosexual couples has proven difficult, and even less is known about gay couples. Resource models of power posit that demographic characteristics associated with social status (e.g., age, income) confer power within the relationship, which in turn shapes relationship outcomes. We tested this model in a sample of gay male couples (N=566 couples), and extended it by examining race and HIV status. Multilevel modeling was used to test associations between demographic bases of power and decision-making power. We also examined relative associations among demographic bases and decision-making power with relationship satisfaction, given the literature on power imbalances and overall relationship functioning. Results showed that individual income was positively associated with decision-making power, as was participant’s HIV status, with HIV-positive men reporting greater power. Age differences within the relationship interacted with relationship length to predict decision-making power, but not satisfaction. HIV-concordant positive couples were less satisfied than concordant negative couples. Higher power partners were less satisfied than lower power partners. Demographic factors contributing to decision-making power among same-sex male couples appear to share some similarities with heterosexual couples (e.g., income is associated with power), as well as have unique features (e.g., HIV status influences power). However, these same demographics did not reliably predict relationship satisfaction in the manner that existing power theories suggest. Findings indicate important considerations for theories of power among same-sex male couples. PMID:27606937

Geomorphic effectiveness of long profile shape and role of inherent geological controls, Ganga River Basin, India

NASA Astrophysics Data System (ADS)

Sonam, Sonam; Jain, Vikrant

2017-04-01

River long profile is one of the fundamental geomorphic parameters which provides a platform to study interaction of geological and geomorphic processes at different time scales. Long profile shape is governed by geological processes at 10 ^ 5 - 10 ^ 6 years' time scale and it controls the modern day (10 ^ 0 - 10 ^ 1 years' time scale) fluvial processes by controlling the spatial variability of channel slope. Identification of an appropriate model for river long profile may provide a tool to analyse the quantitative relationship between basin geology, profile shape and its geomorphic effectiveness. A systematic analysis of long profiles has been carried for the Himalayan tributaries of the Ganga River basin. Long profile shape and stream power distribution pattern is derived using SRTM DEM data (90 m spatial resolution). Peak discharge data from 34 stations is used for hydrological analysis. Lithological variability and major thrusts are marked along the river long profile. The best fit of long profile is analysed for power, logarithmic and exponential function. Second order exponential function provides the best representation of long profiles. The second order exponential equation is Z = K1*exp(-β1*L) + K2*exp(-β2*L), where Z is elevation of channel long profile, L is the length, K and β are coefficients of the exponential function. K1 and K2 are the proportion of elevation change of the long profile represented by β1 (fast) and β2 (slow) decay coefficients of the river long profile. Different values of coefficients express the variability in long profile shapes and is related with the litho-tectonic variability of the study area. Channel slope of long profile is estimated taking the derivative of exponential function. Stream power distribution pattern along long profile is estimated by superimposing the discharge and long profile slope. Sensitivity analysis of stream power distribution with decay coefficients of the second order exponential equation is evaluated for a range of coefficient values. Our analysis suggests that the amplitude of stream power peak value is dependent on K1, the proportion of elevation change coming under the fast decay exponent and the location of stream power peak is dependent of the long profile decay coefficient (β1). Different long profile shapes owing to litho-tectonic variability across the Himalayas are responsible for spatial variability of stream power distribution pattern. Most of the stream power peaks lie in the Higher Himalaya. In general, eastern rivers have higher stream power in hinterland area and low stream power in the alluvial plains. This is responsible for, 1) higher erosion rate and sediment supply in hinterland of eastern rivers, 2) the incised and stable nature of channels in the western alluvial plains and 3) aggrading channels with dynamic nature in the eastern alluvial plains. Our study shows that the spatial variability of litho-units defines the coefficients of long profile function which in turn controls the position and magnitude of stream power maxima and hence the geomorphic variability in a fluvial system.
Functional integral for non-Lagrangian systems

NASA Astrophysics Data System (ADS)

Kochan, Denis

2010-02-01

A functional integral formulation of quantum mechanics for non-Lagrangian systems is presented. The approach, which we call “stringy quantization,” is based solely on classical equations of motion and is free of any ambiguity arising from Lagrangian and/or Hamiltonian formulation of the theory. The functionality of the proposed method is demonstrated on several examples. Special attention is paid to the stringy quantization of systems with a general A-power friction force -κq˙A. Results for A=1 are compared with those obtained in the approaches by Caldirola-Kanai, Bateman, and Kostin. Relations to the Caldeira-Leggett model and to the Feynman-Vernon approach are discussed as well.
What graph theory actually tells us about resting state interictal MEG epileptic activity.

PubMed

Niso, Guiomar; Carrasco, Sira; Gudín, María; Maestú, Fernando; Del-Pozo, Francisco; Pereda, Ernesto

2015-01-01

Graph theory provides a useful framework to study functional brain networks from neuroimaging data. In epilepsy research, recent findings suggest that it offers unique insight into the fingerprints of this pathology on brain dynamics. Most studies hitherto have focused on seizure activity during focal epilepsy, but less is known about functional epileptic brain networks during interictal activity in frontal focal and generalized epilepsy. Besides, it is not clear yet which measures are most suitable to characterize these networks. To address these issues, we recorded magnetoencephalographic (MEG) data using two orthogonal planar gradiometers from 45 subjects from three groups (15 healthy controls (7 males, 24 ± 6 years), 15 frontal focal (8 male, 32 ± 16 years) and 15 generalized epileptic (6 male, 27 ± 7 years) patients) during interictal resting state with closed eyes. Then, we estimated the total and relative spectral power of the largest principal component of the gradiometers, and the degree of phase synchronization between each sensor site in the frequency range [0.5-40 Hz]. We further calculated a comprehensive battery of 15 graph-theoretic measures and used the affinity propagation clustering algorithm to elucidate the minimum set of them that fully describe these functional brain networks. The results show that differences in spectral power between the control and the other two groups have a distinctive pattern: generalized epilepsy presents higher total power for all frequencies except the alpha band over a widespread set of sensors; frontal focal epilepsy shows higher relative power in the beta band bilaterally in the fronto-central sensors. Moreover, all network indices can be clustered into three groups, whose exemplars are the global network efficiency, the eccentricity and the synchronizability. Again, the patterns of differences were clear: the brain network of the generalized epilepsy patients presented greater efficiency and lower eccentricity than the control subjects for the high frequency bands, without a clear topography. Besides, the frontal focal epileptic patients showed only reduced eccentricity for the theta band over fronto-temporal and central sensors. These outcomes indicate that functional epileptic brain networks are different to those of healthy subjects during interictal stage at rest, with a unique pattern of dissimilarities for each type of epilepsy. Further, when properly selected, three network indices suffice to provide a comprehensive description of these differences. Yet, since such uniqueness in the pattern of differences is also evident in the power spectrum, we conclude that the added value of the graph theory approach in this context should not be overestimated.
Power and Integrated Health Care: Shifting from Governance to Governmentality

PubMed Central

Rau, Asta; Fourie, Pieter; Bracke, Piet

2016-01-01

Integrated care occurs within micro, meso and macro levels of governance structures, which are shaped by complex power dynamics. Yet theoretically-led notions of power, and scrutiny of its meanings and its functioning, are neglected in the literature on integrated care. We explore an alternative approach. Following a discussion on governance, two streams of theorising power are presented: mainstream and second-stream. Mainstream concepts are based on the notion of power-as-capacity, of one agent having the capacity to influence another—so the overall idea is ‘power over?’. Studies on integrated care typically employ mainstream ideas, which yield rather limited analyses. Second-stream concepts focus on strategies and relations of power—how it is channelled, negotiated and (re)produced. These notions align well with the contemporary shift away from the idea that power is centralised, towards more fluid ideas of power as dispersed and (re)negotiated throughout a range of societal structures, networks and actors. Accompanying this shift, the notion of governance is slowly being eclipsed by that of governmentality. We propose governmentality as a valuable perspective for analysing and understanding power in integrated care. Our contribution aims to address the need for more finely tuned theoretical frameworks that can be used to guide empirical work. PMID:28435425
Predictive Power Estimation Algorithm (PPEA) - A New Algorithm to Reduce Overfitting for Genomic Biomarker Discovery

PubMed Central

Liu, Jiangang; Jolly, Robert A.; Smith, Aaron T.; Searfoss, George H.; Goldstein, Keith M.; Uversky, Vladimir N.; Dunker, Keith; Li, Shuyu; Thomas, Craig E.; Wei, Tao

2011-01-01

Toxicogenomics promises to aid in predicting adverse effects, understanding the mechanisms of drug action or toxicity, and uncovering unexpected or secondary pharmacology. However, modeling adverse effects using high dimensional and high noise genomic data is prone to over-fitting. Models constructed from such data sets often consist of a large number of genes with no obvious functional relevance to the biological effect the model intends to predict that can make it challenging to interpret the modeling results. To address these issues, we developed a novel algorithm, Predictive Power Estimation Algorithm (PPEA), which estimates the predictive power of each individual transcript through an iterative two-way bootstrapping procedure. By repeatedly enforcing that the sample number is larger than the transcript number, in each iteration of modeling and testing, PPEA reduces the potential risk of overfitting. We show with three different cases studies that: (1) PPEA can quickly derive a reliable rank order of predictive power of individual transcripts in a relatively small number of iterations, (2) the top ranked transcripts tend to be functionally related to the phenotype they are intended to predict, (3) using only the most predictive top ranked transcripts greatly facilitates development of multiplex assay such as qRT-PCR as a biomarker, and (4) more importantly, we were able to demonstrate that a small number of genes identified from the top-ranked transcripts are highly predictive of phenotype as their expression changes distinguished adverse from nonadverse effects of compounds in completely independent tests. Thus, we believe that the PPEA model effectively addresses the over-fitting problem and can be used to facilitate genomic biomarker discovery for predictive toxicology and drug responses. PMID:21935387
Muscle function in avian flight: achieving power and control

PubMed Central

Biewener, Andrew A.

2011-01-01

Flapping flight places strenuous requirements on the physiological performance of an animal. Bird flight muscles, particularly at smaller body sizes, generally contract at high frequencies and do substantial work in order to produce the aerodynamic power needed to support the animal's weight in the air and to overcome drag. This is in contrast to terrestrial locomotion, which offers mechanisms for minimizing energy losses associated with body movement combined with elastic energy savings to reduce the skeletal muscles' work requirements. Muscles also produce substantial power during swimming, but this is mainly to overcome body drag rather than to support the animal's weight. Here, I review the function and architecture of key flight muscles related to how these muscles contribute to producing the power required for flapping flight, how the muscles are recruited to control wing motion and how they are used in manoeuvring. An emergent property of the primary flight muscles, consistent with their need to produce considerable work by moving the wings through large excursions during each wing stroke, is that the pectoralis and supracoracoideus muscles shorten over a large fraction of their resting fibre length (33–42%). Both muscles are activated while being lengthened or undergoing nearly isometric force development, enhancing the work they perform during subsequent shortening. Two smaller muscles, the triceps and biceps, operate over a smaller range of contractile strains (12–23%), reflecting their role in controlling wing shape through elbow flexion and extension. Remarkably, pigeons adjust their wing stroke plane mainly via changes in whole-body pitch during take-off and landing, relative to level flight, allowing their wing muscles to operate with little change in activation timing, strain magnitude and pattern. PMID:21502121
Constraining the CO intensity mapping power spectrum at intermediate redshifts

NASA Astrophysics Data System (ADS)

Padmanabhan, Hamsa

2018-04-01

We compile available constraints on the carbon monoxide (CO) 1-0 luminosity functions and abundances at redshifts 0-3. This is used to develop a data driven halo model for the evolution of the CO galaxy abundances and clustering across intermediate redshifts. It is found that the recent constraints from the CO Power Spectrum Survey (z ˜ 3; Keating et al. 2016), when combined with existing observations of local galaxies (z ˜ 0; Keres, Yun & Young 2003), lead to predictions that are consistent with the results of smaller surveys at intermediate redshifts (z ˜ 1-2). We provide convenient fitting forms for the evolution of the CO luminosity-halo mass relation, and estimates of the mean and uncertainties in the CO power spectrum in the context of future intensity mapping experiments.
Power optimization of ultrasonic friction-modulation tactile interfaces.

PubMed

Wiertlewski, Michael; Colgate, J Edward

2015-01-01

Ultrasonic friction-modulation devices provide rich tactile sensation on flat surfaces and have the potential to restore tangibility to touchscreens. To date, their adoption into consumer electronics has been in part limited by relatively high power consumption, incompatible with the requirements of battery-powered devices. This paper introduces a method that optimizes the energy efficiency and performance of this class of devices. It considers optimal energy transfer to the impedance provided by the finger interacting with the surface. Constitutive equations are determined from the mode shape of the interface and the piezoelectric coupling of the actuator. The optimization procedure employs a lumped parameter model to simplify the treatment of the problem. Examples and an experimental study show the evolution of the optimal design as a function of the impedance of the finger.
Axial force and efficiency tests of fixed center variable speed belt drive

NASA Technical Reports Server (NTRS)

Bents, D. J.

1981-01-01

An investigation of how the axial force varies with the centerline force at different speed ratios, speeds, and loads, and how the drive's transmission efficiency is affected by these related forces is described. The tests, intended to provide a preliminary performance and controls characterization for a variable speed belt drive continuously variable transmission (CVT), consisted of the design and construction of an experimental test rig geometrically similar to the CVT, and operation of that rig at selected speed ratios and power levels. Data are presented which show: how axial forces exerted on the driver and driven sheaves vary with the centerline force at constant values of speed ratio, speed, and output power; how the transmission efficiency varies with centerline force and how it is also a function of the V belt coefficient; and the axial forces on both sheaves as normalized functions of the traction coefficient.
GABAergic modulation of visual gamma and alpha oscillations and its consequences for working memory performance.

PubMed

Lozano-Soldevilla, Diego; ter Huurne, Niels; Cools, Roshan; Jensen, Ole

2014-12-15

Impressive in vitro research in rodents and computational modeling has uncovered the core mechanisms responsible for generating neuronal oscillations. In particular, GABAergic interneurons play a crucial role for synchronizing neural populations. Do these mechanistic principles apply to human oscillations associated with function? To address this, we recorded ongoing brain activity using magnetoencephalography (MEG) in healthy human subjects participating in a double-blind pharmacological study receiving placebo, 0.5 mg and 1.5 mg of lorazepam (LZP; a benzodiazepine upregulating GABAergic conductance). Participants performed a demanding visuospatial working memory (WM) task. We found that occipital gamma power associated with WM recognition increased with LZP dosage. Importantly, the frequency of the gamma activity decreased with dosage, as predicted by models derived from the rat hippocampus. A regionally specific gamma increase correlated with the drug-related performance decrease. Despite the system-wide pharmacological intervention, gamma power drug modulations were specific to visual cortex: sensorimotor gamma power and frequency during button presses remained unaffected. In contrast, occipital alpha power modulations during the delay interval decreased parametrically with drug dosage, predicting performance impairment. Consistent with alpha oscillations reflecting functional inhibition, LZP affected alpha power strongly in early visual regions not required for the task demonstrating a regional specific occipital impairment. GABAergic interneurons are strongly implicated in the generation of gamma and alpha oscillations in human occipital cortex where drug-induced power modulations predicted WM performance. Our findings bring us an important step closer to linking neuronal dynamics to behavior by embracing established animal models. Copyright © 2014 Elsevier Ltd. All rights reserved.
Environmental and economic analysis of power generation in a thermophilic biogas plant.

PubMed

Ruiz, D; San Miguel, G; Corona, B; Gaitero, A; Domínguez, A

2018-08-15

This paper investigates the environmental and economic performance of the power production from biogas using Life Cycle Assessment, Life Cycle Costing and Cost Benefit Analysis methodologies. The analysis is based on a commercial thermophilic biogas plant located in Spain where is installed a Combined Heat and Power system that produces electricity that is sold to the grid. Power generation has been assumed as the only function of the biogas system, expanding the system boundaries to include the additional function related to the end-of-life management of the biowastes. Thus environmental burdens from the conventional management of residues were calculated separately and subtracted. The base scenario involves using agri-food waste, sewage sludge and pig/cow manure as substrates. This situation is compared against an alternative scenario where the production of synthetic fertilizer is surrogated by the digestate. The results have shown that the most impacting activities in all impacts categories of power production are primarily attributable to the operation and maintenance of the biogas plant except for water resource depletion and climate change. The avoided emissions associated with the conventional management of pig/cow manure more than offset GHG emissions of the biogas system resulting in a negative impact value of -73.9gCO 2 eq/kWh in the base case scenario. The normalized results show that local impact categories such as primarily human toxicity, fresh water ecotoxicity and particulate matter are the most significantly affected by the biogas system while global impact categories as climate change and ozone depletion are less severely affected. The operation and maintenance phase is also shown to be the largest contributor after the life cycle cost analysis, followed by the construction and dismantling of the biogas plant and the profitability of the project is primarily related to the income obtained from the management of the biowastes used as substrates. Copyright © 2018 Elsevier B.V. All rights reserved.
Extended Krylov subspaces approximations of matrix functions. Application to computational electromagnetics

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

Druskin, V.; Lee, Ping; Knizhnerman, L.

There is now a growing interest in the area of using Krylov subspace approximations to compute the actions of matrix functions. The main application of this approach is the solution of ODE systems, obtained after discretization of partial differential equations by method of lines. In the event that the cost of computing the matrix inverse is relatively inexpensive, it is sometimes attractive to solve the ODE using the extended Krylov subspaces, originated by actions of both positive and negative matrix powers. Examples of such problems can be found frequently in computational electromagnetics.
Perturbed generalized multicritical one-matrix models

NASA Astrophysics Data System (ADS)

Ambjørn, J.; Chekhov, L.; Makeenko, Y.

2018-03-01

We study perturbations around the generalized Kazakov multicritical one-matrix model. The multicritical matrix model has a potential where the coefficients of zn only fall off as a power 1 /n s + 1. This implies that the potential and its derivatives have a cut along the real axis, leading to technical problems when one performs perturbations away from the generalized Kazakov model. Nevertheless it is possible to relate the perturbed partition function to the tau-function of a KdV hierarchy and solve the model by a genus expansion in the double scaling limit.
Resting-State Oscillatory Activity in Children Born Small for Gestational Age: An MEG Study

PubMed Central

Boersma, Maria; de Bie, Henrica M. A.; Oostrom, Kim J.; van Dijk, Bob W.; Hillebrand, Arjan; van Wijk, Bernadette C. M.; Delemarre-van de Waal, Henriëtte A.; Stam, Cornelis J.

2013-01-01

Growth restriction in utero during a period that is critical for normal growth of the brain, has previously been associated with deviations in cognitive abilities and brain anatomical and functional changes. We measured magnetoencephalography (MEG) in 4- to 7-year-old children to test if children born small for gestational age (SGA) show deviations in resting-state brain oscillatory activity. Children born SGA with postnatally spontaneous catch-up growth [SGA+; six boys, seven girls; mean age 6.3 year (SD = 0.9)] and children born appropriate for gestational age [AGA; seven boys, three girls; mean age 6.0 year (SD = 1.2)] participated in a resting-state MEG study. We calculated absolute and relative power spectra and used non-parametric statistics to test for group differences. SGA+ and AGA born children showed no significant differences in absolute and relative power except for reduced absolute gamma band power in SGA children. At the time of MEG investigation, SGA+ children showed significantly lower head circumference (HC) and a trend toward lower IQ, however there was no association of HC or IQ with absolute or relative power. Except for reduced absolute gamma band power, our findings suggest normal brain activity patterns at school age in a group of children born SGA in which spontaneous catch-up growth of bodily length after birth occurred. Although previous findings suggest that being born SGA alters brain oscillatory activity early in neonatal life, we show that these neonatal alterations do not persist at early school age when spontaneous postnatal catch-up growth occurs after birth. PMID:24068993
Research on the Test of Transmission Line Galloping

NASA Astrophysics Data System (ADS)

Zhang, Lichun; Li, Qing; lv, Zhongbin; Ji, Kunpeng; Liu, Bin

2018-03-01

The load of iced transmission line and the load generated by galloping after the conductor are covered by ice all may cause severe circuit faults, such as tripping, conductor breaking, armor clamp damage and even tower collapse, thus severely threatening running safety of power system. The generation and development processes of galloping of power transmission line is very complicated, and numerous factors may influence the galloping excitation, such as environmental factors, terrain factors and structural parameters of power transmission line; in which, the ice covering of conductor is one of necessary factors causing galloping. Therefore, researches on ice covering increasing test of different types of conductors under different meteorological conditions have been conducted in large-sized multi-functional phytotron, thus obtaining the relation curve of ice covering increasing of conductor along with time under different conditions, and analyzing factors influencing increasing of ice covering. The research result shows that under the same ice covering conditions, the increasing of ice covering of conductor with small diameter is relatively rapid; both environmental temperature and wind speed have obvious influence on increasing of ice covering of conductor, and the environmental temperature will decide the type of ice covering of conductor surface. Meanwhile, after wind tunnel tests targeting conductors with different ice covering shapes, pneumatic stability loss characteristics of conductors with different ice shapes have been obtained. Research results have important scientific reference value for revealing the mechanism of galloping of iced power transmission line, and have relatively high engineering practicability value for promoting realization of early warning system for galloping of iced power transmission line.
Flipping the switch: power, social dominance, and expectancies of mental energy change.

PubMed

Egan, Patrick M; Hirt, Edward R

2015-03-01

Research suggests that high levels of interpersonal power can promote enhanced executive functioning capabilities. The present work explored whether this effect is contingent upon expectancies concerning power's downstream cognitive consequences. Study 1 showed that social dominance orientation (SDO) predicted idiosyncratic expectancies of mental energy change toward interpersonal power. Study 2 showed that SDO moderated the executive functioning changes associated with interpersonal power and that this moderation effect was contingent upon changes in perceived mental depletion. Study 3 showed that directly manipulating expectancies of mental energy change concerning interpersonal power moderated the executive functioning consequences of power and that this moderation effect was contingent upon SDO and changes in perceived mental depletion. Together, the present findings underscore the importance of expectancies and individual differences in understanding the effects of interpersonal power. © 2014 by the Society for Personality and Social Psychology, Inc.
Proton exchange membrane and electrode surface areas as factors that affect power generation in microbial fuel cells.

PubMed

Oh, Sang-Eun; Logan, Bruce E

2006-03-01

Power generation in microbial fuel cells (MFCs) is a function of the surface areas of the proton exchange membrane (PEM) and the cathode relative to that of the anode. To demonstrate this, the sizes of the anode and cathode were varied in two-chambered MFCs having PEMs with three different surface areas (A (PEM)=3.5, 6.2, or 30.6 cm(2)). For a fixed anode and cathode surface area (A (An)=A (Cat)=22.5 cm(2)), the power density normalized to the anode surface area increased with the PEM size in the order 45 mW/m(2) (A (PEM)=3.5 cm(2)), 68 mW/m(2) (A (PEM)=6.2 cm(2)), and 190 mW/m(2) (A (PEM)=30.6 cm(2)). PEM surface area was shown to limit power output when the surface area of the PEM was smaller than that of the electrodes due to an increase in internal resistance. When the relative cross sections of the PEM, anode, and cathode were scaled according to 2A (Cat)=A(PEM)=2A (An), the maximum power densities of the three different MFCs, based on the surface area of the PEM (A (PEM)=3.5, 6.2, or 30.6 cm(2)), were the same (168+/-4.53 mW/m(2)). Increasing the ionic strength and using ferricyanide at the cathode also increased power output.
On the analysis of EEG power, frequency and asymmetry in Parkinson's disease during emotion processing.

PubMed

Yuvaraj, Rajamanickam; Murugappan, Murugappan; Mohamed Ibrahim, Norlinah; Iqbal, Mohd; Sundaraj, Kenneth; Mohamad, Khairiyah; Palaniappan, Ramaswamy; Mesquita, Edgar; Satiyan, Marimuthu

2014-04-09

While Parkinson's disease (PD) has traditionally been described as a movement disorder, there is growing evidence of disruption in emotion information processing associated with the disease. The aim of this study was to investigate whether there are specific electroencephalographic (EEG) characteristics that discriminate PD patients and normal controls during emotion information processing. EEG recordings from 14 scalp sites were collected from 20 PD patients and 30 age-matched normal controls. Multimodal (audio-visual) stimuli were presented to evoke specific targeted emotional states such as happiness, sadness, fear, anger, surprise and disgust. Absolute and relative power, frequency and asymmetry measures derived from spectrally analyzed EEGs were subjected to repeated ANOVA measures for group comparisons as well as to discriminate function analysis to examine their utility as classification indices. In addition, subjective ratings were obtained for the used emotional stimuli. Behaviorally, PD patients showed no impairments in emotion recognition as measured by subjective ratings. Compared with normal controls, PD patients evidenced smaller overall relative delta, theta, alpha and beta power, and at bilateral anterior regions smaller absolute theta, alpha, and beta power and higher mean total spectrum frequency across different emotional states. Inter-hemispheric theta, alpha, and beta power asymmetry index differences were noted, with controls exhibiting greater right than left hemisphere activation. Whereas intra-hemispheric alpha power asymmetry reduction was exhibited in patients bilaterally at all regions. Discriminant analysis correctly classified 95.0% of the patients and controls during emotional stimuli. These distributed spectral powers in different frequency bands might provide meaningful information about emotional processing in PD patients.
On the Theoretical Framework of Magnetized Outflows from Stellar-Mass Black Holes and Related Observations

NASA Technical Reports Server (NTRS)

Christodoulou, D. M.; Contopoulos, I.; Kazanas, D.; Steiner, J. F.; Papadopoulos, D. B.; Laycock, S. G. T.

2016-01-01

The spins of stellar-mass black holes (BHs) and the power outputs of their jets are measurable quantities. Unfortunately, the currently employed methods do not agree and the results are controversial. Two major issues concern the measurements of BH spin and beam (jet) power. The former issue can be resolved by future observations. But the latter issue can be resolved now, if we pay attention to what is expected from theoretical considerations. The question of whether a correlation has been found between the power outputs of few objects and the spins of their BHs is moot because BH beam power does not scale with the square of the spin of the BH. We show that the theoretical BH beam power is a strongly nonlinear function of spin that cannot be approximated by a quadratic relation, as is generally stated when the influence of the magnetic field is not accounted for in the Blandford & Znajek model. The BH beam power of ballistic jets should scale a lot more steeply with BH spin irrespective of the magnetic field assumed to thread the horizon and the spin range considered. This behavior may already be visible in the analyses of radio observations by Narayan & McClintock and Russell et al. In agreement with previous studies, we also find that the power output that originates in the inner regions of the surrounding accretion disks is higher than that from the BHs and it cannot be ignored in investigations of continuous compact jets from these systems.
Across-Platform Imputation of DNA Methylation Levels Incorporating Nonlocal Information Using Penalized Functional Regression.

PubMed

Zhang, Guosheng; Huang, Kuan-Chieh; Xu, Zheng; Tzeng, Jung-Ying; Conneely, Karen N; Guan, Weihua; Kang, Jian; Li, Yun

2016-05-01

DNA methylation is a key epigenetic mark involved in both normal development and disease progression. Recent advances in high-throughput technologies have enabled genome-wide profiling of DNA methylation. However, DNA methylation profiling often employs different designs and platforms with varying resolution, which hinders joint analysis of methylation data from multiple platforms. In this study, we propose a penalized functional regression model to impute missing methylation data. By incorporating functional predictors, our model utilizes information from nonlocal probes to improve imputation quality. Here, we compared the performance of our functional model to linear regression and the best single probe surrogate in real data and via simulations. Specifically, we applied different imputation approaches to an acute myeloid leukemia dataset consisting of 194 samples and our method showed higher imputation accuracy, manifested, for example, by a 94% relative increase in information content and up to 86% more CpG sites passing post-imputation filtering. Our simulated association study further demonstrated that our method substantially improves the statistical power to identify trait-associated methylation loci. These findings indicate that the penalized functional regression model is a convenient and valuable imputation tool for methylation data, and it can boost statistical power in downstream epigenome-wide association study (EWAS). © 2016 WILEY PERIODICALS, INC.

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